MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'American Journal of Physiology. Cell Physiology' source. Tue, 07 Feb 2012 08:48:50 +0100 http://www.medworm.com/index.php?rid=5623481&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22262062%26dopt%3DAbstract In this study, by using yeast two-hybrid screening, we identified the cytoskeletal protein actin as a binding partner with the UT-A1 urea transporter. This suggests that actin plays a role in regulating UT-A1 activity. Actin specifically binds to the carboxyl terminus of UT-A1. A serial mutation study shows that actin binding to UT-A1's carboxyl terminus was abolished when serine 918 was mutated to alanine. In polarized UT-A1-MDCK cells, cortical filamentous (F) actin co-localizes with UT-A1 at the apical membrane and the subapical cytoplasm. In the cell surface, both actin and UT-A1 are distributed in the lipid raft microdomains. Disruption of the F-actin cytoskeleton by latrunculin B resulted in UT-A1 accumulation in the cell membrane as measured by biotinylation. This effect was mainly ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5623481 Wed, 18 Jan 2012 05:00:00 +0100 5623481 http://www.medworm.com/index.php?rid=5623480&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22262063%26dopt%3DAbstract Authors: Sabolic I, Vrhovac I, Balen Eror D, Gerasimova M, Rose M, Breljak D, Ljubojevic M, Brzica H, Sebastiani A, Thal SC, Sauvant C, Kipp H, Vallon V, Koepsell H Abstract Using a novel antibody against the rat Na(+)-D-glucose cotransporter SGLT2 (rSGLT2-Ab), which does not cross-react with rSGLT1 or rSGLT3, the ~75 kDa rSGLT2 protein was localized to the brush border membrane (BBM) of the renal proximal tubule S1 and S2 segments (S1>S2) with female-dominant expression in adult rats, whereas the rSglt2 mRNA expression was similar in both sexes. Castration of adult males increased the abundance of rSGLT2 protein; this increase was further enhanced by estradiol and prevented by testosterone treatment. In the renal BBM vesicles, the rSGLT1-independent uptake of [(14)C]-α-methyl-... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5623480 Wed, 18 Jan 2012 05:00:00 +0100 5623480 http://www.medworm.com/index.php?rid=5623479&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22262064%26dopt%3DAbstract Authors: Ozdemir T, Zhang P, Fu C, Dong C Abstract Elevated soluble fibrin (sFn) levels are characteristic of melanoma hematogeneous dissemination, where tumor cells interact intimately with host cells. Melanoma adhesion to the blood vessel wall is promoted by immune cell arrests and tumor-derived thrombin, a serine protease that converts soluble fibrinogen (sFg) into sFn. However, the molecular requirement for sFn-mediated melanoma-polymorphonuclear neutrophils (PMNs) and melanoma-endothelial interactions under physiological flow conditions remain elusive. To understand this process, we studied the relative binding capacities of sFg and sFn receptors e.g., α(v)β(3) integrin and intercellular adhesion molecule 1 (ICAM-1) expressed on melanoma cells, ICAM-1 on endothelial cells (E... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5623479 Wed, 18 Jan 2012 05:00:00 +0100 5623479 http://www.medworm.com/index.php?rid=5578621&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22218225%26dopt%3DAbstract Authors: Sharma NM, Zheng H, Li YF, Patel KP Abstract We have previously observed an increased of angiotensin II (ANG II) type 1 receptor (AT(1)R) with enhanced AT(1)R-mediated sympathetic outflow and concomitant down-regulation of neuronal nitric oxide (NO) synthase (nNOS) with reduced NO mediated inhibition from the paraventricular nucleus (PVN) in rats with heart failure. To test the hypothesis that NO exerts an inhibitory effect on AT(1)R expression in the PVN, we used primary cultured hypothalamic cells of neonatal rats and neuronal cell line NG108-15 as in vitro models. In hypothalamic primary culture, NO donor sodium nitroprusside (SNP) induced dose-dependent decreases in mRNA and protein of AT(1)R (10(-5) M SNP, AT(1)R protein was 10±2% of control level) while NOS inhibito... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5578621 Wed, 04 Jan 2012 05:00:00 +0100 5578621 http://www.medworm.com/index.php?rid=5560893&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22205391%26dopt%3DAbstract Authors: Chinthamani S, Odusanwo O, Mondal N, Nelson J, Neelamegham S, Baker OJ Abstract Lipoxins are formed by leukocytes during cell-cell interactions with epithelial or endothelial cells. Native lipoxin A(4) (LXA(4)) binds to the G protein-coupled lipoxin receptors FPR2/ALX and CysLT1. Furthermore, LXA(4) inhibits recruitment of neutrophils, by attenuating chemotaxis, adhesion and transmigration across vascular endothelial cells. LXAA(4) thus appears to serve as an endogenous "stop signal" for immune cell-mediated tissue injury (78). The role of LXAA(4) has not been addressed in salivary epithelium and little is known about their effects on vascular endothelium. Here, we determined that interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) receptor activation in vascula... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5560893 Wed, 28 Dec 2011 05:00:00 +0100 5560893 http://www.medworm.com/index.php?rid=5560892&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22205392%26dopt%3DAbstract This study supports a novel role of ASIC1 in elevated receptor-stimulated vasoconstriction following CH which is likely mediated through increased ASIC1 expression and SOCE. PMID: 22205392 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5560892 Wed, 28 Dec 2011 05:00:00 +0100 5560892 http://www.medworm.com/index.php?rid=5513849&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22173866%26dopt%3DAbstract Authors: Borst O, Abed M, Alesutan I, Towhid ST, Qadri SM, Föller M, Gawaz M, Lang F Abstract Suicidal death of erythrocytes or eryptosis is characterized by cell shrinkage and cell membrane scrambling leading to phosphatidylserine exposure at the cell surface. Eryptosis is triggered by increase of cytosolic Ca(2+) activity, which may result from treatment with the Ca(2+) ionophore ionomycin or from energy depletion by removal of glucose. The present study tested the hypothesis that phosphatidylserine exposure at the erythrocyte surface fosters adherence to endothelial cells of the vascular wall under flow conditions at arterial shear rates and that binding of eryptotic cells to endothelial cells is mediated by the transmembrane CXC chemokine ligand 16 (CXCL16). To this end, human... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513849 Wed, 14 Dec 2011 05:00:00 +0100 5513849 http://www.medworm.com/index.php?rid=5513848&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22173867%26dopt%3DAbstract PRESTEADY-STATE AND REVERSE TRANSPORT CURRENTS IN THE GABA TRANSPORTER GAT1. Am J Physiol Cell Physiol. 2011 Dec 14; Authors: Cherubino F, Bertram S, Bossi E, Peres A Abstract The role of internal substrates on the biophysical properties of GAT1 has been investigated electrophysiologically in Xenopus oocytes heterologously expressing the cotransporter. Increments in the Cl(-) and/or Na(+) concentrations caused by intracellular injections did not produce significant effects on the presteady-state currents, while a positive shift of the Q-V and τ-V curves together with a slowing down of this last quantity at positive potentials were observed following treatments producing cytosolic chloride depletion. Activation of the reverse transport mode by injections of GABA caused a re... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513848 Wed, 14 Dec 2011 05:00:00 +0100 5513848 http://www.medworm.com/index.php?rid=5513847&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22173868%26dopt%3DAbstract Authors: Dolan JM, Sim FJ, Meng H, Kolega J Abstract Chronic high flow can induce arterial remodeling, and this effect is mediated by endothelial cells (ECs) responding to wall shear stress (WSS). To assess how WSS above physiological normal levels affects ECs, we used DNA microarrays to profile EC gene expression under various flow conditions. Cultured bovine aortic ECs were exposed to no flow (0 Pa), normal WSS (2 Pa) and very high WSS (10 Pa) for 24 hrs. Very high WSS induced a distinct expression profile when compared to both no flow and normal WSS. Gene ontology and biological pathway analysis revealed that high WSS modulated gene expression in ways that promote an anti-coagulant, anti-inflammatory, proliferative and pro-matrix remodeling phenotype. A subset of characteristic ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513847 Wed, 14 Dec 2011 05:00:00 +0100 5513847 http://www.medworm.com/index.php?rid=5513846&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22173869%26dopt%3DAbstract Conclusions: These data suggest that anandamide suppresses I(to) through a non-CB1 and non-CB2 receptor-mediated pathway, while augments I(KATP) through CB(2) receptors in ventricular myocytes. PMID: 22173869 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513846 Wed, 14 Dec 2011 05:00:00 +0100 5513846 http://www.medworm.com/index.php?rid=5513861&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159077%26dopt%3DAbstract Authors: Haito-Sugino S, Ito M, Ohi A, Shiozaki Y, Kangawa N, Nishiyama T, Aranami F, Sasaki S, Mori A, Kido S, Tatsumi S, Segawa H, Miyamoto KI Abstract Mutations in the apically located Na(+)-dependent phosphate (NaPi) co-transporter, SLC34A3 (NaPi-IIc), are a cause of hereditary hypophosphatemic rickets with hypercalciuria (HHRH). We have characterized the impact of several HHRH mutations on the processing and stability of human NaPi-IIc. Mutations S138F, G196R, R468W, R564C and c.288delC in human NaPi-IIc significantly decreased the levels of NaPi co-transport activities in Xenopus oocytes. In S138F and R564C mutant proteins, this reduction is a result of a decrease in the Vmax for Pi, but not the Km. G196R, R468W and c.288delC mutants were not localized to oocyte membranes. In... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513861 Wed, 07 Dec 2011 05:00:00 +0100 5513861 http://www.medworm.com/index.php?rid=5513860&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159078%26dopt%3DAbstract Authors: Zhou Y, Munoz J, Jiang D, Jarrett HW Abstract In our previous studies, we showed laminin binds α-dystroglycan in the dystrophin glycoprotein complex and initiates cell signaling pathways. Here, differentiated C2C12 myocytes serve as a model of skeletal muscle. C2C12 cells have a biphasic response to the laminin-α1 LG4-5 domains (1E3) dependent on the concentration used; at low concentration of 1E3 (<1 μg/ml) myoblast proliferation is increased while higher concentrations (>1 μg/ml) cause apoptosis in myoblasts and differentiated myotubes. This alters the activation of the transcription factors AP1 and NF-κB via laminin-DGC-src-grb2-sos1-Rac1-Pak1-JNKp46 and laminin-DGC-Gβγ-PI3K/Akt pathways, respectively. A specific antibody against Ser(63) phosphorylated c-ju... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513860 Wed, 07 Dec 2011 05:00:00 +0100 5513860 http://www.medworm.com/index.php?rid=5513859&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159079%26dopt%3DAbstract Authors: Saito H, Yamamoto Y, Yamamoto H Abstract Circulating endothelial progenitor cells (EPCs) derived from the bone marrow (BM) participate in maintaining endothelial integrity and vascular homeostasis. Reduced EPC number and function result in vascular complications in diabetes. EPCs are a population of cells existing in various differentiation stages, and their cell surface marker profiles change during the process of mobilization and maturation. Hence, a generally accepted marker combination and a standardized protocol for the quantification of EPC remain to be established. To determine the EPC subsets that are affected by diabetes, we comprehensively analyzed 32 surface marker combinations of mouse peripheral blood (PB), BM, and spleen cells by multicolor flow cytometry. Te... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513859 Wed, 07 Dec 2011 05:00:00 +0100 5513859 http://www.medworm.com/index.php?rid=5513858&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159080%26dopt%3DAbstract Authors: Chang MH, Plata C, Kurita Y, Kato A, Hirose S, Romero MF Abstract Marine fish drink sea water and eliminate excess salt by active salt transport across gill and gut epithelia. Euryhaline pufferfish (Takifugu obscurus, mefugu) forms a CaCO(3) precipitate on the luminal gut surface after transitioning to sea water. NBCe1 (Slc4a4) at the basolateral membrane of intestinal epithelial cell plays major role of transepithelial intestinal HCO(3)(-) secretion and is critical for mefugu acclimation to sea water. We assayed fugu-NBCe1 (fNBCe1) activity in Xenopus oocytes expression system. Similar to NBCe1 found in other species, fNBCe1 is an electrogenic Na(+)/HCO(3)(-) cotransporter and sensitive to the stilbene inhibitor, DIDS. However, our experiments revealed several unique and ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513858 Wed, 07 Dec 2011 05:00:00 +0100 5513858 http://www.medworm.com/index.php?rid=5513857&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159081%26dopt%3DAbstract Authors: Morris GE, Nelson CP, Brighton PJ, Standen NB, Challiss RA, Willets JM Abstract Over-stimulation of endothelin type A (ET(A)) and nucleotide (P2Y) Gα(q)-coupled receptors in vascular smooth muscle causes vasoconstriction, hypertension and eventually hypertrophy and vascular occlusion. G protein-coupled receptor kinases (GRKs) and arrestin proteins are sequentially recruited by agonist-occupied Gα(q)-coupled receptors to terminate phospholipase C (PLC) signaling, preventing prolonged/inappropriate contractile signaling. However, these proteins also play roles in the regulation of several mitogen-activated protein-kinase (MAPK) signaling cascades known to be essential for vascular remodeling. Here we investigated whether different arrestin isoforms regulate endothelin and ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513857 Wed, 07 Dec 2011 05:00:00 +0100 5513857 http://www.medworm.com/index.php?rid=5513856&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159082%26dopt%3DAbstract Authors: Sala-Rabanal M, Hirayama BA, Loo DD, Chaptal V, Abramson J, Wright EM Abstract The Na(+) glucose cotransporter hSGLT1 is a member of a class of membrane proteins that harness Na(+) electrochemical gradients to drive uphill solute transport. While hSGLT1 belongs to one gene family (SLC5), recent structural studies of bacterial Na(+) cotransporters show that Na(+ )transporters in different gene families have the same structural fold. We have constructed homology models of hSGLT1 in two conformations, the inward facing occluded (based on vSGLT), and the outward open (based on Mhp1) conformations, mutated in turn each of the conserved gates and ligand binding residues, expressed the SGLT1 mutants in Xenopus oocytes, and determined the functional consequences using biophysical ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513856 Wed, 07 Dec 2011 05:00:00 +0100 5513856 http://www.medworm.com/index.php?rid=5513855&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159083%26dopt%3DAbstract We report unexpected nongenomic functions of "transcription factor" STAT5 species in the cytoplasm aimed at preserving the structure and function of the Golgi apparatus and rough endoplasmic reticulum (ER) in vascular cells. Immunoimaging and GFP-tagged-STAT5a protein localization studies showed the constitutive association of non-phosphorylated STAT5a, and to a lesser extent STAT5b, with the Golgi apparatus and of STAT5a with centrosomes in human pulmonary arterial endothelial and smooth muscle cells. Acute knockdown of STAT5a/b species using siRNAs, including in the presence of an mRNA synthesis inhibitor (5,6-dichloro-1-β-D-ribofuranosylbenzimidazole), produced a dramatic phenotype within 1 day consisting of dilatation and fragmentation of Golgi cisternae, a marked tubule to cyst chang... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513855 Wed, 07 Dec 2011 05:00:00 +0100 5513855 http://www.medworm.com/index.php?rid=5513854&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159084%26dopt%3DAbstract In conclusion, our data indicate that N-glycosylation of SLC26A3 is important for cell surface expression and for protection from proteolytic degradation that may contribute to the understanding of pathogenesis of congenital disorders of glycosylation. PMID: 22159084 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513854 Wed, 07 Dec 2011 05:00:00 +0100 5513854 http://www.medworm.com/index.php?rid=5513853&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159085%26dopt%3DAbstract Authors: Wesch D, Althaus M, Miranda P, Cruz-Muros I, Fronius M, González-Hernández T, Clauss WG, Alvarez de la Rosa D, Giraldez T Abstract The epithelial Na(+) channel (ENaC) is a heteromultimeric ion channel that plays a key role in Na(+) reabsorption across tight epithelia. The canonical ENaC is formed by three analogous subunits, α, β and γ. A fourth ENaC subunit, named δ, is expressed in the nervous system of primates, where its role is unknown. The human δ ENaC gene generates at least two splice isoforms, δ1 and δ2, differing in the N-terminal sequence. Neurons in diverse areas of the human and monkey brain differentially express either δ1 or δ2, with few cells co-expressing both isoforms, which suggests that they may play specific physiological roles. Here we show... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513853 Wed, 07 Dec 2011 05:00:00 +0100 5513853 http://www.medworm.com/index.php?rid=5513852&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159086%26dopt%3DAbstract ELEVATED AMMONIUM LEVELS: DIFFERENTIAL ACUTE EFFECTS ON THREE GLUTAMATE TRANSPORTER ISOFORMS. Am J Physiol Cell Physiol. 2011 Dec 7; Authors: Søgaard R, Novak I, Macaulay N Abstract Increased ammonium (NH(4)(+)/NH(3)) in the brain is a significant factor in the pathophysiology of hepatic encephalopathy, which involves altered glutamatergic neurotransmission. In glial cell cultures and brain slices, glutamate uptake either decreases or increases following acute ammonium exposure but the factors responsible for the opposing effects are unknown. Excitatory amino acid transporter isoforms EAAT1, EAAT2 and EAAT3 were expressed in Xenopus oocytes to study effects of ammonium exposure on their individual function. Ammonium increased EAAT1- and EAAT3-mediated [(3)H]-glutamate upta... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513852 Wed, 07 Dec 2011 05:00:00 +0100 5513852 http://www.medworm.com/index.php?rid=5513851&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159087%26dopt%3DAbstract Authors: Parsons SP, Kunze WA, Huizinga JD Abstract Ion channels are fundamental to gastrointestinal pacemaking by Interstitial cells of Cajal (ICC). Previously we have recorded a high-conductance chloride channel (HCCC) from ICC, both in culture and in situ associated with the myenteric plexus. The biophysical properties of the HCCC (conductance, subconductances, voltage- and time-dependent inactivation) suggest it is a member of a class called the maxi-anion channels. Here we further investigated the properties of the HCCC in situ. Our main finding was that the HCCC is not strictly a chloride channel, but has a relative sodium-chloride permeability (P(Na/Cl)) of 0.76 to 1.64 (depending of the method of measurement). Therefore we renamed the HCCC the "maxi-channel". A maxi-channel... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513851 Wed, 07 Dec 2011 05:00:00 +0100 5513851 http://www.medworm.com/index.php?rid=5513850&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22159088%26dopt%3DAbstract Authors: Goedecke S, Roderigo C, Rose CR, Rauch BH, Goedecke A, Schrader J Abstract ATP and its degradation products play an import role as signaling molecules in the vascular system, and endothelial cells are considered to be an important source of nucleotide release. In order to investigate the mechanism and physiological significance of endothelial ATP release, we compared different pharmacological stimuli for their ability to evoke ATP release from first passage cultivated human umbilical vein endothelial cells (HUVECs). Agonists known to increase intracellular Ca(2+) levels (A23187, histamine, thrombin) induced a stable, non-lytic ATP release. Since thrombin proved to be the most robust and reproducible stimulus, the molecular mechanism of thrombin-mediated ATP release from HU... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513850 Wed, 07 Dec 2011 05:00:00 +0100 5513850 http://www.medworm.com/index.php?rid=5513865&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22135213%26dopt%3DAbstract Authors: Pattnaik BR, Hughes BA Abstract Recently, we demonstrated the expression of KCNQ1, KCNQ4, and KCNQ5 transcripts in monkey retinal pigment epithelium (RPE) and showed that the M-type current in RPE cells is blocked by the specific KCNQ channel blocker XE991. Here, we investigated the pharmacological sensitivity of the M-type current in isolated monkey RPE cells using patch-clamp electrophysiology to elucidate the subunit composition of the channel. Most RPE cells exhibited an M-type current with a voltage for half-maximal activation of ~ 35 mV. The M-type current activation followed a double-exponential time course and was essentially complete within 1 sec. The M-type current was inhibited by micromolar concentrations of the non-selective KCNQ channel blockers linopirdine a... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513865 Wed, 30 Nov 2011 05:00:00 +0100 5513865 http://www.medworm.com/index.php?rid=5513864&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22135214%26dopt%3DAbstract Authors: Mason MJ, Schaffner C, Floto RA, Teo QA Abstract Whole cell patch-clamp experiments were undertaken to define the basal K(+) conductance(s) in HEL cells and their contribution to the setting of resting membrane potential. Experiments revealed a non-voltage-activated, non-inactivating K(+) current. The magnitude of the current recorded under whole-cell conditions was inhibited by increasing the free intracellular Mg(2+) concentration. Activation or inactivation of the Mg(2+)-inhibited potassium current (MIP) was paralleled by activation or inactivation of a Mg2+-inhibited TRPM7-like current displaying characteristics indistinguishable from those reported for molecularly identified TRPM7. Both the MIP and TRPM7 currents were inhibited by 5-lipoxygenase inhibitors. However, i... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513864 Wed, 30 Nov 2011 05:00:00 +0100 5513864 http://www.medworm.com/index.php?rid=5513863&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22135215%26dopt%3DAbstract In this study, we examined the endothelial effects of estrogen under increasing glucose levels focusing on nitrotyrosine and peroxynitrite. Human umbilical vein endothelial cells (HUVECs) were incubated with normal (5.5 mM) or high (15.5 or 30.5 mM) glucose prior to addition of estradiol (E2, 1 or 10 nM). Selective NO synthase (NOS) inhibitors were used to determine the role of specific NOS isoforms. Addition of E2 significantly reduced high glucose-induced increase in peroxynitrite and consequently, nitrotyrosine. The superoxide levels were unchanged, suggesting effects on NO generation. Inhibition of neuronal NOS (nNOS) reduced high glucose induced nitrotyrosine, demonstrating a critical role for this enzyme. E2 increased nNOS activity under normal glucose while decreasing it under high ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513863 Wed, 30 Nov 2011 05:00:00 +0100 5513863 http://www.medworm.com/index.php?rid=5513862&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22135216%26dopt%3DAbstract We report here that thiopental, a common anesthetic agent, triggers insulin secretion from the intact pancreas and primary cultured rat pancreatic beta cells. We investigated the underlying mechanisms by measurements of whole-cell K(+) and Ca(2+) currents, membrane potential, cytoplasmic Ca(2+) concentration ([Ca(2+)](i)) and membrane capacitance. Thiopental-induced insulin secretion was first detected by enzyme-linked immunoassay, then further assessed by membrane capacitance measurement, which revealed kinetics distinct from glucose-induced insulin secretion. The thiopental-induced secretion was independent of cell membrane depolarization and closure of K(ATP) channels. However, accompanied by the insulin secretion stimulated by thiopental, we recorded a significant intracellular [Ca(2+)... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513862 Wed, 30 Nov 2011 05:00:00 +0100 5513862 http://www.medworm.com/index.php?rid=5513872&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22094329%26dopt%3DAbstract Authors: Bai JP, Surguchev A, Joshi P, Gross L, Navaratnam D Abstract Large conductance calcium activated potassium (BK) channels are ubiquitous and play an important role in a number of diseases. In hair cells of the ear they play a critical role in electrical tuning, a mechanism of frequency discrimination. These channels show variable kinetics and expression along the tonotopic axis. Although the molecular underpinnings to its function in hair cells are poorly understood it is established that BK channels consist of a pore forming alpha subunit (Slo) and a number of accessory subunits. Here we identify CDK5, a member of the cyclin dependent kinase family as an interacting partner of Slo. We show CDK5 to be present in hair cells, and expressed in high concentrations in the cuticu... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513872 Wed, 16 Nov 2011 05:00:00 +0100 5513872 http://www.medworm.com/index.php?rid=5513871&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22094330%26dopt%3DAbstract In conclusion, we provide evidence that FoxO3 activity is negatively modulated by acetylation and ubiquitination in a time-dependent and coordinated manner. This fine-tuning mechanism of FoxO3 regulation may be important to prevent excessive muscle loss and can be used as therapeutic approach to counteract muscle wasting. PMID: 22094330 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513871 Wed, 16 Nov 2011 05:00:00 +0100 5513871 http://www.medworm.com/index.php?rid=5513870&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22094331%26dopt%3DAbstract Authors: Fuentes-Calvo I, Blazquez-Medela AM, Eleno N, Santos E, Lopez-Novoa JM, Martinez-Salgado C Abstract Ras GTPases are ubiquitous plasma membrane transducers of extracellular stimuli. In addition to their role as oncogenes, Ras GTPases are key regulators of cell function. Each of the Ras isoforms exhibits specific modulatory activity on different cellular pathways. This has prompted researchers to determine the pathophysiological roles of each isoform. There is a proven relationship between the signalling pathways of TGF-β1 and Ras GTPases. To assess the individual role of H-Ras oncogene in basal and TGF-β1-mediated extracellular matrix (ECM) synthesis, proliferation and migration in fibroblasts, we analysed these processes in embryonic fibroblasts obtained from H-Ras knock... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513870 Wed, 16 Nov 2011 05:00:00 +0100 5513870 http://www.medworm.com/index.php?rid=5513869&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22094332%26dopt%3DAbstract Conclusions: These data in VSMCs indicate that high palmitate decreases insulin-stimulated Akt phosphorylation & stimulates MAP-K, whereas pre-exposure PPAR-γ agonist pioglitazone preserves Akt phosphorylation and simultaneously attenuates MAP-K signaling. Our results suggest that metabolic and mitogenic insulin signals have different sensitivity, are independently regulated and may play a role in arterial smooth muscle cells migration, proliferation and inflammation in conditions of acute hyperinsulinemia. PMID: 22094332 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513869 Wed, 16 Nov 2011 05:00:00 +0100 5513869 http://www.medworm.com/index.php?rid=5513868&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22094333%26dopt%3DAbstract In this study, we performed two sets of experiments in which activated fibers (pCa(2+) 4.5) treated with the myosin inhibitor blebbistatin were stretched from 2.7μm to 2.8µm at a speed of 40L(o)•s(-1) (i) after partial extraction of TnC, which inhibits myosin-actin interactions, or (ii) after treatment with gelsolin, which leads to the depletion of thin (actin) filaments. We observed that the static tension, directly related with the residual force enhancement, was not changed after treatments that inhibit myosin-actin interactions or that deplete fibers from troponin C (TnC) and actin filaments. The results suggest that the residual force enhancement is caused by a stiffening of titin upon muscle activation, but not with titin binding to actin. This finding indicates the existence of ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513868 Wed, 16 Nov 2011 05:00:00 +0100 5513868 http://www.medworm.com/index.php?rid=5513867&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22094334%26dopt%3DAbstract Conclusions: The present study indicated that MS of bone tissue elicited afferent P2X receptor mediated purinergic transmission to sensory neurons in all stages mice. This transmission is modulated by satellite cells, which may have protective actions on sensory neurons. PMID: 22094334 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513867 Wed, 16 Nov 2011 05:00:00 +0100 5513867 http://www.medworm.com/index.php?rid=5513866&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22094335%26dopt%3DAbstract Authors: Yang B, Gwozdz T, Dutko-Gwozdz J, Bolotina VM Abstract Store-operated Ca(2+) entry (SOCE) is important for multiple functions of vascular smooth muscle cells (SMC), which, depending of their phenotype, can resemble excitable and non-excitable cells. Similar to non-excitable cells, Orai1 was found to mediate Ca(2+)-selective (CRAC-like) current and SOCE in dedifferentiated cultured SMC and smooth muscle-derived cell lines. However, the role of Orai1 in cation-selective store-operated channels (cat-SOC) that are responsible for SOCE in primary SMC remains unclear. Here we focus on primary SMC, and assess the role of Orai1 and Ca(2+)-independent phospholipase A(2) (iPLA(2)β, or PLA2G6) in activation of cat-SOC current (Icat-SOC), SOCE, and SMC proliferation. Using molecular,... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5513866 Wed, 16 Nov 2011 05:00:00 +0100 5513866 http://www.medworm.com/index.php?rid=5421948&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22075691%26dopt%3DAbstract Authors: Gokhin DS, Kim NE, Lewis SA, Hoenecke HR, D'Lima DD, Fowler VM Abstract Force production in skeletal muscle is proportional to the amount of overlap between the thin and thick filaments, which, in turn, depends on their lengths. Both thin and thick filament lengths are precisely regulated and uniform within a myofibril. While thick filament lengths are essentially constant across muscles and species (~1.65 μm), thin filament lengths are highly variable both across species and across muscles of a single species. Here, we used a high-resolution immunofluorescence and image analysis technique (distributed deconvolution) to directly test the hypothesis that thin filament lengths vary across human muscles. Using deltoid and pectoralis major muscle biopsies, we identified thin ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5421948 Wed, 09 Nov 2011 05:00:00 +0100 5421948 http://www.medworm.com/index.php?rid=5421947&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22075692%26dopt%3DAbstract In this study, triiodothyronine (T3) treatment induced UCP1 expression and mitochondrial biogenesis accompanied by the induction of the CCAAT/enhancer binding protein, peroxisome proliferator-activated receptor γ coactivator 1α, and nuclear respiratory factor 1 in differentiated human multipotent adipose-derived stem cells. The effects of T3 on UCP1 induction were dependent on TH receptor β. Moreover, T3 treatment increased oxygen consumption rate. These findings indicate that T3 is an active modulator, which induces energy utilization in white adipocytes through the regulation of UCP1 expression and mitochondrial biogenesis. Our findings provide evidence that T3 serves as a bipotential mediator of mitochondrial biogenesis. PMID: 22075692 [PubMed - as supplied by publisher] (Source:... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5421947 Wed, 09 Nov 2011 05:00:00 +0100 5421947 http://www.medworm.com/index.php?rid=5421946&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22075693%26dopt%3DAbstract Authors: Duran C, Qu Z, Osunkoya AO, Cui Y, Hartzell HC Abstract Ca(2+)-activated Cl(-) channels (CaCCs) participate in numerous physiological functions such as neuronal excitability, sensory transduction, and transepithelial fluid transport. Recently it was shown that heterologously expressed anoctamins ANO1 and ANO2 generate currents that resemble native CaCCs. The anoctamin family (also called Tmem16) consists of 10 members, but it is not known whether all members of the family are CaCCs. Expression of ANOs 3-7 in HEK293 cells did not generate Cl(-) currents activated by intracellular Ca(2+), as determined by whole-cell patch clamp electrophysiology. Using confocal imaging, only ANO1 and ANO2 traffic to the plasma membrane when expressed heterologously. Furthermore, endogenously... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5421946 Wed, 09 Nov 2011 05:00:00 +0100 5421946 http://www.medworm.com/index.php?rid=5421945&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22075694%26dopt%3DAbstract Authors: Andrini O, Meinild AK, Ghezzi C, Murer H, Forster IC Abstract Type IIa/b Na(+)-coupled inorganic phosphate cotransporters (NaPi-IIa/b) are considered to be exclusively Na(+) dependent. Here we show that Li(+) can substitute for Na(+) as a driving cation. We expressed NaPi-IIa/b in X. laevis oocytes and performed two-electrode voltage-clamp electrophysiology and uptake assays to investigate the effect of external Li(+) on their kinetics. Replacement of 50% external Na(+) with Li(+) reduced the maximum transport rate and the rate-limiting plateau of the Pi-induced current began at less hyperpolarizing potentials. Simultaneous electrophysiology and 22Na uptake on single oocytes revealed that Li(+) ions can substitute for at least one of the 3 Na(+) ions necessary for cotransp... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5421945 Wed, 09 Nov 2011 05:00:00 +0100 5421945 http://www.medworm.com/index.php?rid=5421944&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22075695%26dopt%3DAbstract Authors: Bhattacharyya BJ, Wilson SM, Jung H, Miller RJ Abstract Homozygous ataxic mice (ax(J)) express reduced levels of the deubiquitinating enzyme Usp 14. They develop severe tremors by 2-3 weeks of age, followed by hind limb paralysis, and death by 6-8 weeks. While changes in the ubiquitin proteasome system often result in the accumulation of ubiquitin protein aggregates and neuronal loss, these pathological markers are not observed in the ax(J) mice. Instead, defects in neurotransmission were observed in both the central and peripheral nervous systems of ax(J) mice. We have now identified several new alterations in peripheral neurotransmission in the ax(J) mice. Using the two-microelectrode voltage clamp technique on diaphragm muscles of ax(J) mice, we observed that under norm... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5421944 Wed, 09 Nov 2011 05:00:00 +0100 5421944 http://www.medworm.com/index.php?rid=5298166&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21975424%26dopt%3DAbstract Authors: Nissar AA, Zemanek B, Labatia R, Atkinson DJ, van der Ven PF, Fürst DO, Hawke TJ Abstract Xin is a striated muscle-specific actin-binding protein whose mRNA expression has been observed in damaged skeletal muscle. Here we demonstrate increased Xin protein expression early post-injury (≤12 hours) and localization primarily to the periphery of damaged myofibers. At 1 day post-injury, Xin is co-localized with MyoD, confirming expression in activated satellite cells (SCs). By 5 days post-injury, Xin is evident in newly-regenerated myofibers, with a return to pre-injury levels by 14 days of regeneration. To determine if the increased Xin expression is functionally relevant, tibialis anterior muscles of wild-type mice were infected with Xin-shRNA adenovirus, while the contral... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5298166 Wed, 05 Oct 2011 04:00:00 +0100 5298166 http://www.medworm.com/index.php?rid=5298165&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21975425%26dopt%3DAbstract Authors: Ecelbarger CM Abstract Tyrosine phosphorylation plays a fundamental role in the determination and maintenance of apico-basal and planar cell polarity. However, it has been a difficult area to study due to the relative rarity of tyrosine versus serine or threonine phosphorylation events. In epithelial cells, polarity, and thus asymmetry, is an essential requirement the transport of solutes and water from one body compartment to another in the maintenance of normal body fluid osmolality. However, which proteins and specific tyrosine residues are involved and which receptor-related signaling cascades may be regulatory in this maintenance is not well defined. Zhao and colleagues utilize several novel approaches to comprehensively reveal and define tyrosine phosphorylation site... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5298165 Wed, 05 Oct 2011 04:00:00 +0100 5298165 http://www.medworm.com/index.php?rid=5298164&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21975426%26dopt%3DAbstract Authors: Larkins NT, Murphy RM, Lamb GD Abstract Heat shock proteins (HSPs) are essential for normal cellular stress responses. Absolute amounts of HSP72, HSP25 and αB-crystallin in rat extensor digitorum longus (EDL) and soleus (SOL) muscle were ascertained by quantitative western blotting, in order to better understand their respective capabilities and limitations. HSP72 content of EDL and SOL muscle was only ~1.1 and 4.6 μμmol/kg wet weight, respectively, and HSP25 content ~2 fold greater (~3.4 and ~8.9 μμmol/kg, respectively). αB crystallin content of EDL muscle was ~4.9 μmol/kg, but in SOL muscle was ~30 fold higher (~140 μmol/kg). To examine fiber heterogeneity, HSP content was also assessed in individual fiber segments; every EDL type II fiber had less of each HSP th... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5298164 Wed, 05 Oct 2011 04:00:00 +0100 5298164 http://www.medworm.com/index.php?rid=5298163&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21975427%26dopt%3DAbstract Authors: Liu L, Rao JN, Zou T, Xiao L, Smith A, Zhuang R, Turner DJ, Wang JY Abstract In response to mucosal injury, epithelial cells modify the patterns of expressed genes in order to repair damaged tissue rapidly. Our previous studies have demonstrated that the transcription factor c-Myc is necessary for stimulation of epithelial cell renewal during mucosal healing, but the up-stream signaling initiating c-Myc gene expression after injury remains unknown. Wnts are cysteine-rich glycoproteins that act as short-range ligands to locally activate receptor-mediated signaling pathways and correlate with the increased expression of the c-Myc gene. The current study tested the hypothesis that Wnt3a signaling is implicated in intestinal epithelial repair after wounding by stimulating c-My... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5298163 Wed, 05 Oct 2011 04:00:00 +0100 5298163 http://www.medworm.com/index.php?rid=5281468&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562309%26dopt%3DAbstract Authors: Arcangeli A Abstract The traditional view of cancer as a collection of proliferating cells must be reconsidered, and cancer must be viewed as a "tissue" constituted by both transformed cells and a heterogeneous microenvironment, that tumor cells construct and remodel during multistep tumorigenesis. The "tumor microenvironment" (TM) is formed by mesenchymal, endothelial, and immune cells immersed in a network of extracellular matrix (ECM) proteins and soluble factors. The TM strongly contributes to tumor progression, through long distance, cell-to-cell or cell-to-matrix signals, which influence different aspects of tumor cell behavior. Understanding the relationships among the different components of the cancer tissue is crucial to design and develop new therapeutic strateg... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281468 Sat, 01 Oct 2011 04:00:00 +0100 5281468 http://www.medworm.com/index.php?rid=5281467&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21677259%26dopt%3DAbstract Authors: Fatma N, Singh P, Chhunchha B, Kubo E, Shinohara T, Bhargavan B, Singh DP Abstract The multifunctional cytoprotective protein peroxiredoxin 6 (Prdx6) maintains cellular homeostasis and membrane integrity by regulating expression of intracellular reactive oxygen species (ROS) and phospholipid turnover. Using cells derived from targeted inactivation of Prdx6 gene or its depletion by RNA interference or aging, we showed that Prdx6 deficiency in cells evoked unfolded protein response (UPR), evidenced by increased expression or activation of proapoptotic factors, CHOP, ATF4, PERK, IRE-α and eIF2-α and by increased caspases 3 and 12 processing. Those cells displayed enhanced and sustained expression of endoplasmic reticulum (ER) stress-related chaperon proteins, Bip/glucose-re... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281467 Sat, 01 Oct 2011 04:00:00 +0100 5281467 http://www.medworm.com/index.php?rid=5281466&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21697543%26dopt%3DAbstract Authors: Hristov KL, Chen M, Kellett WF, Rovner ES, Petkov GV Abstract The large-conductance voltage- and Ca(2+)-activated K(+) (BK) channel is expressed in many smooth muscle types, but its role in human detrusor smooth muscle (DSM) is unclear. With a multidisciplinary approach spanning channel molecules, single-channel activity, freshly isolated human DSM cells, intact DSM preparations, and the BK channel specific inhibitor iberiotoxin, we elucidated human DSM BK channel function and regulation. Native human DSM tissues were obtained during open surgeries from patients with no preoperative history of overactive bladder. RT-PCR experiments on single human DSM cells showed mRNA expression of BK channel α-, β(1)-, and β(4)-subunits. Western blot and immunocytochemistry confirmed ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281466 Sat, 01 Oct 2011 04:00:00 +0100 5281466 http://www.medworm.com/index.php?rid=5281465&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21734186%26dopt%3DAbstract Authors: Kotlo KU, Hesabi B, Danziger RS Abstract MicroRNAs (miRs) are endogenous small RNA molecules that suppress gene expression by binding to complementary sequences in the 3' untranslated regions of their target genes. miRs have been implicated in many diseases, including heart failure, ischemic heart disease, hypertension, cardiac hypertrophy, and cancers. Nitric oxide (NO) and atrial natriuretic peptide (ANP) are potent vasorelaxants whose actions are mediated through receptor guanylyl cyclases and cGMP-dependent protein kinase. The present study examines miRs in signaling by ANP and NO in vascular smooth muscle cells. miR microarray analysis was performed on human vascular smooth muscle cells (HVSMC) treated with ANP (10 nM, 4 h) and S-nitroso-N-acetylpenicillamine (SNAP) (... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281465 Sat, 01 Oct 2011 04:00:00 +0100 5281465 http://www.medworm.com/index.php?rid=5281463&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21753185%26dopt%3DAbstract This study provides the first demonstration that the presence of the α(7)β(1)-integrin in skeletal muscle increases fiber hypertrophy and new fiber synthesis in the early time course following a single bout of eccentric exercise. Further studies are necessary to elucidate the precise mechanism by which the α(7)-integrin can enhance muscle hypertrophy following exercise. PMID: 21753185 [PubMed - in process] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281463 Sat, 01 Oct 2011 04:00:00 +0100 5281463 http://www.medworm.com/index.php?rid=5281462&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21775704%26dopt%3DAbstract Leukocyte rolling and adhesion via ICAM-1 signals to endothelial permeability. Focus on "Leukocyte rolling and adhesion both contribute to regulation of microvascular permeability to albumin via ligation of ICAM-1". Am J Physiol Cell Physiol. 2011 Oct;301(4):C777-9 Authors: Williams MR, Luscinskas FW PMID: 21775704 [PubMed - in process] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281462 Sat, 01 Oct 2011 04:00:00 +0100 5281462 http://www.medworm.com/index.php?rid=5281461&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21775705%26dopt%3DAbstract This report uses an in vitro model with human umbilical vein endothelial cells and isolated human neutrophils to examine the effects of two locally derived cytokines, granulocyte (G)-macrophage (M) colony-stimulating factor (GM-CSF) and G-CSF, on oncostatin M (OSM) expression. Neutrophils contacting activated HUVEC expressed and released increased amounts of oncostatin M (OSM), a proinflammatory cytokine known to induce polymorphonuclear neutrophil adhesion and chemotaxis. Neutrophil transendothelial migration resulted in threefold higher OSM expression and protein levels compared with nontransmigrated cells. Addition of anti-GM-CSF neutralizing antibody reduced OSM expression level but anti-G-CSF was without effect. GM-CSF but not G-CSF protein addition to cultures of isolated neutrophils... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281461 Sat, 01 Oct 2011 04:00:00 +0100 5281461 http://www.medworm.com/index.php?rid=5281460&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21775708%26dopt%3DAbstract How uniform is cAMP signaling? Focus on "Systems analysis of GLP-1 receptor signaling in pancreatic {beta}-cells". Am J Physiol Cell Physiol. 2011 Oct;301(4):C775-6 Authors: Harvey RD PMID: 21775708 [PubMed - in process] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281460 Sat, 01 Oct 2011 04:00:00 +0100 5281460 http://www.medworm.com/index.php?rid=5281459&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795524%26dopt%3DAbstract Authors: Kleyman TR, Insel PA, Frank M PMID: 21795524 [PubMed - in process] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281459 Sat, 01 Oct 2011 04:00:00 +0100 5281459 http://www.medworm.com/index.php?rid=5281458&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21832247%26dopt%3DAbstract Neurokinin 1 receptor desensitization and resensitization: is it all happening at the membrane? Focus on "Protein phosphatase 2A mediates resensitization of the neurokinin 1 receptor". Am J Physiol Cell Physiol. 2011 Oct;301(4):C772-4 Authors: Rozengurt E PMID: 21832247 [PubMed - in process] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281458 Sat, 01 Oct 2011 04:00:00 +0100 5281458 http://www.medworm.com/index.php?rid=5281457&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21956163%26dopt%3DAbstract Authors: Biswas A, Senthilkumar SR, Said HM Abstract Mammalian cells obtain folate, a water-soluble vitamin, from their surroundings via transport across cell membrane. Intracellular folate is compartmentalized between the cytoplasm and the mitochondria. Transport of folate from the cytoplasm into the mitochondria is via a specific carrier-mediated process involving the mitochondrial folate transporter (MFT). Chronic alcohol use negatively impacts folate homeostasis, but its effect on mitochondrial folate uptake is not clear. We addressed this issue using mitochondrial preparations isolated from the liver of rats chronically fed an alcohol liquid diet, and from human liver HepG2 cells chronically exposed to alcohol. The results showed that chronic alcohol feeding of rats leads to a... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281457 Wed, 28 Sep 2011 04:00:00 +0100 5281457 http://www.medworm.com/index.php?rid=5281456&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21956164%26dopt%3DAbstract Authors: Nighot PK, Blikslager AT Abstract Previously, we have demonstrated that the chloride channel ClC-2 modulates intestinal mucosal barrier function. In the present study, we investigated the role of ClC-2 in epithelial barrier development and maintenance in Caco-2 cells. During early monolayer formation, silencing of ClC-2 with siRNA led to a significant delay in the development of transepithelial resistance (TER), and disruption of occludin localization. Proteomic analysis employing LC-MS/mass spectrometry revealed association of ClC-2 with key proteins involved in intracellular trafficking, including caveolin-1 and Rab5. In ClC-2 siRNA treated cells, occludin colocalization with caveolin-1 was diffuse and in the sub apical region. Sub apically distributed occludin in ClC-2 ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281456 Wed, 28 Sep 2011 04:00:00 +0100 5281456 http://www.medworm.com/index.php?rid=5281455&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21956165%26dopt%3DAbstract Authors: Pisitkun T, Hoffert JD, Saeed F, Knepper MA Abstract Investigation of physiological mechanisms at a cellular level often requires production of high quality antibodies, frequently using synthetic peptides as immunogens. Here we describe a new, web-based software tool called NHLBI-AbDesigner that allows the user to visualize the information needed to choose optimal peptide sequences for peptide-directed antibody production (http://helixweb.nih.gov/AbDesigner/). The choice of an immunizing peptide is generally based on a need to optimize immunogenicity, antibody specificity, multi-species conservation, and robustness in the face of post-translational modifications (PTMs). AbDesigner displays information relevant to these criteria as follows: 1) Immunogenicity Score, based on... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281455 Wed, 28 Sep 2011 04:00:00 +0100 5281455 http://www.medworm.com/index.php?rid=5281454&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21956166%26dopt%3DAbstract Authors: Hassan HA, Cheng M, Aronson PS Abstract Urolithiasis remains a very common disease in Western countries. 70-80% of kidney stones are composed of calcium oxalate and minor changes in urinary oxalate affect stone risk. Intestinal oxalate secretion mediated by anion exchanger SLC26A6 plays a major constitutive role in limiting net absorption of ingested oxalate, thereby preventing hyperoxaluria and calcium oxalate urolithiasis. Using the relatively selective PKC-δ inhibitor rottlerin, we had previously found that PKC-δ activation inhibits Slc26a6 activity in mouse duodenal tissue. To identify a model system to study physiologic agonists upstream of PKC-δ, we characterized the human intestinal cell line T84. knockdown studies demonstrated that endogenous SLC26A6 mediates mo... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281454 Wed, 28 Sep 2011 04:00:00 +0100 5281454 http://www.medworm.com/index.php?rid=5281453&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21956167%26dopt%3DAbstract Targeting therapeutic effects: sub-cellular location matters. Focus on "Pharmacological AMPK activators have compartment-specific effects on cell physiology" Am J Physiol Cell Physiol. 2011 Sep 28; Authors: Creighton J Abstract Editorial focus commentary on the article by Kodiha et al titled: "Pharmacological AMP-kinase activators have compartment-specific effects on cell physiology" PMID: 21956167 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5281453 Wed, 28 Sep 2011 04:00:00 +0100 5281453 http://www.medworm.com/index.php?rid=5231738&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21918180%26dopt%3DAbstract The objectives of the present study were first to determine the compartment-specific effects of three established AMPK activators on Thr172 phosphorylation of the α-subunit, an indicator of AMPK activation. Second, we examined how cytoplasmic and nuclear processes are modulated by pharmacological AMPK activators. Specifically, the impact of phenformin, resveratrol and AICAR on Thr172 phosphorylation in the cytoplasm and nucleus was quantified by different methods. To analyze how these activators change cell physiology, we measured the inactivation of acetyl-CoA-carboxylase 1, a predominantly cytoplasmic enzyme that is crucial for lipid metabolism. As a criterion for activities associated with the nucleus, de novo RNA synthesis in nucleoli was quantified. Our studies demonstrate that pharm... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5231738 Wed, 14 Sep 2011 04:00:00 +0100 5231738 http://www.medworm.com/index.php?rid=5231737&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21918181%26dopt%3DAbstract Authors: Summermatter S, Turnheer R, Santos G, Mosca B, Baum O, Treves S, Hoppeler H, Zorzato F, Handschin C Abstract Regular endurance exercise remodels skeletal muscle, largely through the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α). PGC-1α promotes fiber-type switching and resistance to fatigue. Intracellular calcium levels might play a role in both adaptive phenomena, yet a role for PGC-1α in the adaptation of calcium handling in skeletal muscle remains unknown. Using mice with transgenic over-expression of PGC-1α, we now investigated the effect of PGC-1α on calcium handling in skeletal muscle. We demonstrate that PGC-1α induces a quantitative reduction in calcium release from the sarcoplasmic reticulum by diminishing the expression of calcium r... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5231737 Wed, 14 Sep 2011 04:00:00 +0100 5231737 http://www.medworm.com/index.php?rid=5231736&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21918182%26dopt%3DAbstract Authors: Bugaj V, Mironova E, Kohan DE, Stockand JD Abstract Collecting duct (CD)-derived endothelin-1 (ET-1) acting via endothelin B (ETB) receptors promotes Na+ excretion. Compromise of ET-1 signaling or ETB receptors in the CD cause sodium retention and increase blood pressure. Activity of the epithelial Na(+) channel (ENaC) is limiting for Na(+) reabsorption in the CD. To test for ETB receptor regulation of ENaC, we combined patch clamp electrophysiology with CD-specific knockout of endothelin receptors. We also tested how ET-1 signaling via specific endothelin receptors influences ENaC activity under differing dietary Na(+) regimens. ET-1 significantly decreased ENaC open probability in CD isolated from wild type (wt) and CD ETA KO mice but not CD ETB KO and CD ETA/B KO mice. ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5231736 Wed, 14 Sep 2011 04:00:00 +0100 5231736 http://www.medworm.com/index.php?rid=5231735&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21918183%26dopt%3DAbstract In conclusion, these results provide strong evidence that purinergic activation of a calcium-dependent, apamin-sensitive potassium conductance is essential to promote chloride secretion and thus fluid formation in the oviduct. PMID: 21918183 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5231735 Wed, 14 Sep 2011 04:00:00 +0100 5231735 http://www.medworm.com/index.php?rid=5219305&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21900687%26dopt%3DAbstract Authors: Lokireddy S, Mouly V, Butler-Browne G, Gluckman PD, Sharma M, Kambadur R, McFarlane C Abstract Myostatin is a negative regulator of skeletal muscle growth and in fact acts as a potent inducer of "cachectic-like" muscle wasting in mice. The mechanism of action of Myostatin in promoting muscle wasting has been predominantly studied in murine models. Despite numerous reports linking elevated levels of Myostatin to human skeletal muscle wasting conditions, little is currently known about the signaling mechanism(s) through which Myostatin promotes human skeletal muscle wasting. Therefore, in this present study we describe in further detail the mechanisms behind Myostatin regulation of human skeletal muscle wasting using an in vitro human primary myotube atrophy model. Treatment... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5219305 Wed, 07 Sep 2011 04:00:00 +0100 5219305 http://www.medworm.com/index.php?rid=5219304&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21900688%26dopt%3DAbstract Authors: Riddle MA, Hughes JM, Walker BR Abstract A novel vasodilatory influence of endothelial cell (EC) large conductance calcium activated potassium channels (BK(Ca)) is present following in vivo exposure to chronic hypoxia (CH) and may exist in other pathological states. However, the mechanism of channel activation that results in altered vasoreactivity is unknown. We tested the hypothesis that CH removes an inhibitory effect of the scaffolding domain of caveolin-1 on EC BK(Ca) channels to permit activation thereby affecting vasoreactivity. Experiments were performed on gracilis resistance arteries and ECs from control and CH (P(B) = 380 mmHg for 48 hr) exposed rats. EC membrane potential was hyperpolarized in arteries from CH rats or arteries treated with the cholesterol deple... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5219304 Wed, 07 Sep 2011 04:00:00 +0100 5219304 http://www.medworm.com/index.php?rid=5219303&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21900689%26dopt%3DAbstract Authors: Chandrakala AN, Sukul D, Selvarajan K, Sai-Sudhakar C, Sun B, Parthasarathy S Abstract Brain natriuretic peptide (BNP) and monocyte chemotactic protein-1 (MCP-1) are biomarkers of heart failure (HF). The present study was aimed to determine the role of oxidized low-density lipoprotein (Ox-LDL) in the induction of these biomarkers and the signaling pathways involved in vitro. Incubation of HL-1 cardiomyocytes and human myocytes with Ox-LDL induced the expression of BNP and MCP-1 genes, while native LDL (N-LDL) had no effect. When peroxides associated with Ox-LDL were reduced to hydroxides, the ability to induce BNP and MCP-1 gene expressions was abolished. Furthermore, exposure of HL-1 cells to ischemic conditions alone had no effect on BNP gene expression while ischemia fo... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5219303 Wed, 07 Sep 2011 04:00:00 +0100 5219303 http://www.medworm.com/index.php?rid=5219302&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21900690%26dopt%3DAbstract Authors: Hitomi H, Mehta PK, Taniyama Y, Lassègue B, Seidel-Rogol B, San Martin A, Griendling KK Abstract Angiotensin II (Ang II) has been implicated in the pathogenesis of diabetic micro- and macrovascular disease. In vascular smooth muscle cells (VSMCs), Ang II phosphorylates and degrades insulin receptor substrate-1 (IRS-1). While the pathway responsible for IRS-1 degradation in this system is unknown, c-Jun N-terminal kinase (JNK) has been linked with serine phosphorylation of IRS-1 and insulin resistance. We investigated the role of JNK in Ang II-induced IRS-1 phosphorylation, degradation, Akt activation, glucose uptake, and hypertrophic signaling, focusing on three IRS-1 phosphorylation sites: Ser302, Ser307, and Ser632. Maximal IRS-1 phosphorylation on Ser632 occurred at 5 ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5219302 Wed, 07 Sep 2011 04:00:00 +0100 5219302 http://www.medworm.com/index.php?rid=5219301&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21900691%26dopt%3DAbstract Authors: Matsumura CY, Taniguti AP, Pertille A, Santo Neto H, Marques MJ Abstract In Duchenne muscular dystrophy (DMD) and in the mdx mouse model of DMD, the lack of dystrophin is related to enhanced calcium influx and muscle degeneration. Stretch-activated channels (SACs) might be directly involved in the pathology of DMD and transient receptor potential cation channels have been proposed as likely candidates of SACs. We investigated the levels of transient receptor potential canonical channel 1 (TRPC1) and the effects of streptomycin, a SAC blocker, in muscles showing different degrees of the dystrophic phenotype. Mdx mice (18 days old, n=16) received daily intraperitoneal injections of streptomycin (182 mg/kg body weight) for 18 days, followed by removal of the diaphragm, sterno... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5219301 Wed, 07 Sep 2011 04:00:00 +0100 5219301 http://www.medworm.com/index.php?rid=5219300&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21900692%26dopt%3DAbstract Authors: Lafontan M Abstract ABSTRACT Lafontan M. Historical perspectives in fat cell biology: the fat cell as a model for the investigation of hormonal and metabolic pathways. For many years there was little interest in the biochemistry or physiology of adipose tissue. It is now well recognized that adipocytes play an important dynamic role in metabolic regulation. They are able to sense metabolic states via their ability to perceive a large number of nervous and hormonal signals. Moreover, they are also able to produce hormones, called adipokines, that affect nutrient intake, metabolism and energy expenditure. The report by Rodbell (1964) that intact fat cells can be obtained by collagenase digestion of adipose tissue revolutionized studies on the hormonal regulation and metaboli... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5219300 Wed, 07 Sep 2011 04:00:00 +0100 5219300 http://www.medworm.com/index.php?rid=5193091&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21881000%26dopt%3DAbstract Authors: Honda K, Okamoto K, Mochida Y, Ishioka K, Oka M, Maesato K, Ikee R, Moriya H, Hidaka S, Ohtake T, Doi K, Fujita T, Kobayashi S, Noiri E Abstract Maggot debridement therapy (MDT) is effective for treating intractable wounds, but its precise molecular mechanism, including the association between MDT and growth factors, remains unknown. We administered MDT to nine patients (66.3 ± 11.8 yr, 5 male and 4 female) with intractable wounds of lower extremities because they did not respond to conventional therapies. Significant increases of hepatocyte growth factor (HGF) levels were observed in femoral vein blood during 48 hr of MDT (P<0.05), but no significant change was found for vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming gro... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5193091 Tue, 30 Aug 2011 23:00:00 +0100 5193091 http://www.medworm.com/index.php?rid=5193090&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21881001%26dopt%3DAbstract Authors: Azhibekov TA, Wu Z, Padiyar A, Bruggeman LA, Simske JS Abstract TM4SF10 is a claudin-like cell junction protein that is transiently expressed during podocyte development where its expression is downregulated in differentiating podocytes coincident with the appearance of Nephrin at the slit diaphragm. In a yeast two hybrid screen, we identified ADAP, a well known Fyn substrate and Fyn binding partner, as a TM4SF10 interacting protein in mouse kidney. Using co-immunoprecipitation and immunohistochemistry experiments in cultured human podocytes, we show that TM4SF10 co-localizes with Fyn and ADAP, but does not form a stable complex with Fyn. Cytoskeletal changes and phosphorylation events mediated by Fyn activity were reversed by TM4SF10 over-expression, including a decrease ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5193090 Tue, 30 Aug 2011 23:00:00 +0100 5193090 http://www.medworm.com/index.php?rid=5193089&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21881002%26dopt%3DAbstract In conclusion, our data reveal that in mpkCCD cells, prostaglandins decrease AQP2 protein stability by increasing its lysosomal degradation, indicating that in vivo paracrine produced prostaglandins might have a role in lithium-induced NDI via this mechanism. However, lithium affects also AQP2 gene transcription, which is prostaglandin independent. PMID: 21881002 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5193089 Tue, 30 Aug 2011 23:00:00 +0100 5193089 http://www.medworm.com/index.php?rid=5193088&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21881003%26dopt%3DAbstract In conclusion, results from this study demonstrate that slow waves occur within a narrow membrane potential window in the oviduct. Slow waves are dependent upon extracellular calcium and functional SERCA pumps. PMID: 21881003 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5193088 Tue, 30 Aug 2011 23:00:00 +0100 5193088 http://www.medworm.com/index.php?rid=5193087&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21881004%26dopt%3DAbstract Authors: Xinhan L, Matsushita M, Numaza M, Taguchi A, Mitsui K, Kanazawa H Abstract In mammalian cells, nine conserved isoforms of the Na(+)/H(+) exchanger (NHE) are known to be important for pH regulation of the cytoplasm and organellar lumens. NHE1-5 are localized to the plasma membrane, while NHE6-9 are localized to distinct organelles. NHE6 is localized predominantly in endosomal compartments, but is also found in the plasma membrane. To investigate the role of NHE6 in endocytosis, we established NHE6-knockdown HeLa cells and analyzed the effect of this knockdown on endocytotic events. The expression level of NHE6 in knockdown cells was decreased to approximately 15% of the level seen in control cells. Uptake of transferrin was also decreased. No effect was found on the endocyt... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5193087 Tue, 30 Aug 2011 23:00:00 +0100 5193087 http://www.medworm.com/index.php?rid=5193086&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21881005%26dopt%3DAbstract Authors: Watts BA, George T, Sherwood ER, Good DW Abstract Sepsis is associated with defects in renal tubule function but the underlying mechanisms are incompletely understood. Recently we demonstrated that Gram-negative bacterial lipopolysaccharide (LPS) inhibits HCO(3)(-) absorption in the medullary thick ascending limb (MTAL) through activation of Toll-like receptor 4 (TLR4). Here, we examined the mechanisms responsible for inhibition of HCO(3)(-) absorption by basolateral LPS. Adding LPS to the bath decreased HCO(3)(-) absorption by 30% in rat and mouse MTALs perfused in vitro. The inhibition of HCO(3)(-) absorption was eliminated by the MEK/ERK inhibitors U0126 and PD98059. LPS induced a rapid (< 15 min) and sustained (up to 60 min) increase in ERK phosphorylation in microd... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5193086 Tue, 30 Aug 2011 23:00:00 +0100 5193086 http://www.medworm.com/index.php?rid=5176802&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865582%26dopt%3DAbstract We examined this question in trkB.T1 null mice and demonstrate that in vivo neuromuscular performance and nerve-evoked muscle tension are significantly increased. In vitro assays indicated that the gain-in-function in trkB.T1(-/-) animals resulted specifically from an increased muscle contractility, and increased electrically evoked calcium release. In the trkB.T1 null muscle, we identified an increase in Akt activation in resting muscle as well as a significant increase in trkB.FL and Akt activation in response to contractile activity. Based on these findings, we conclude that the trkB signaling pathway might represent a novel target for intervention across diseases characterized by deficits in neuromuscular function. PMID: 21865582 [PubMed - as supplied by publisher] (Source: America... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176802 Tue, 23 Aug 2011 23:00:00 +0100 5176802 http://www.medworm.com/index.php?rid=5176790&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865583%26dopt%3DAbstract Authors: Do MK, Sato Y, Shimizu N, Suzuki T, Shono JI, Mizunoya W, Nakamura M, Ikeuchi Y, Anderson JE, Tatsumi R Abstract Successful regeneration and remodeling of the intramuscular motoneuron network and neuromuscular connections are critical for restoring skeletal muscle function and physiological properties. The regulatory signals of such coordination remain unclear, although axon-guidance molecules may be involved. Recently, satellite cells, resident myogenic stem cells positioned beneath the basal lamina and at high density at the myoneural junction regions of mature fibers, were shown to up-regulate a secreted neural chemorepellent Sema3A in response to in vivo muscle crush injury. The initial report on that expression centered on the observation that hepatocyte growth factor... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176790 Tue, 23 Aug 2011 23:00:00 +0100 5176790 http://www.medworm.com/index.php?rid=5176789&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865584%26dopt%3DAbstract In this study, GPER expression was found in the female rat myometrium by RT-PCR and immunocytochemistry. Using GPER-selective ligands, we assessed the effects of the GPER activation on resting membrane potential and cytosolic calcium concentration,[Ca(2+)](i), in rat myometrial cells, as well as on contractility of rat uterine strips. G-1, a specific GPER agonist, induced a concentration-dependent depolarization and increase in cytosolic Ca(2+) concentration, [Ca(2+)](i) in myometrial cells. The depolarization was abolished in Na(+)-free saline. G-1-induced [Ca(2+)](i) increase was markedly decreased by nifedipine, a L-type Ca(2+) channel blocker, by Ca(2+)- or Na(+)-free saline. Intracellular administration of G-1 produced a faster and transitory increase in [Ca(2+)](i), with a higher amp... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176789 Tue, 23 Aug 2011 23:00:00 +0100 5176789 http://www.medworm.com/index.php?rid=5176787&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865585%26dopt%3DAbstract We describe four unique first exon variants transcribed from individual promoters in diverse human tissues. Tissue specific alternative splicing with exon skipping and alternative splice donor and acceptor site usage further increases diversity of IRAG mRNA variants that encode for N- and C-terminally truncated proteins. At the functional level, C-terminally truncated IRAG variants lacking both the cGKI phosphorylation and the IP3RI interaction site counteract cGMP-mediated inhibition of calcium transients and relaxation of human colonic smooth muscle cells. Since C-terminally truncated IRAG mRNA isoforms are widely expressed in human tissues, our results point to an important role of IRAG variants as negative modulators of NO/cGKI-dependent signaling. The complexity of alternative splicin... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176787 Tue, 23 Aug 2011 23:00:00 +0100 5176787 http://www.medworm.com/index.php?rid=5176786&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865586%26dopt%3DAbstract In this study, we altered "stimulated actin polymerization" by adjusting tissue length and then measured the effect on force augmentation. At optimal tissue length (1.0Lo), force augmentation was observed and was associated with increased prior "stimulated actin polymerization" as evidenced by increased prior Y118 paxillin phosphorylation without changes in prior S3 cofilin or crossbridge phosphorylation. Tissue length, per se, regulated Y118 paxillin phosphorylation, but not S3 cofilin phosphorylation. At short tissue length (0.6Lo), force augmentation was observed and was associated with increased prior "stimulated actin polymerization" as evidenced by reduced prior S3 cofilin phosphorylation without changes in Y118 paxillin or crossbridge phosphorylation. At long tissue lengths (1.4Lo),... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176786 Tue, 23 Aug 2011 23:00:00 +0100 5176786 http://www.medworm.com/index.php?rid=5176782&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865587%26dopt%3DAbstract In this study, we tested the hypotheses that angiogenic induction can be increased and pericyte differentiation decreased by pretreatment of hASCs with hypoxic culture and that hASCs are similar to human bone marrow derived stromal cells (hBMSCs) in these regards. Our data confirms previous studies showing that hASCs: 1) secrete pro-angiogenic proteins, which are upregulated following culture in hypoxia, and 2) migrate up gradients of PDGF-BB in vitro, while showing for the first time that a rat mesenteric model of angiogenesis induced by 48-80 increases the propensity of both hASCs and hBMSCs to assume perivascular phenotypes following injection. Moreover, culture of both cell types in hypoxia prior to injection results in a biphasic vascular length density response in this model of infla... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176782 Tue, 23 Aug 2011 23:00:00 +0100 5176782 http://www.medworm.com/index.php?rid=5176776&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865588%26dopt%3DAbstract Authors: Wagner J, Allman E, Taylor A, Ulmschneider K, Kovanda T, Ulmschneider B, Nehrke K, Peters MA Abstract Caenorhabditis elegans defecation is a rhythmic behavior, comprised of three sequential muscle contractions, with a fifty-second periodicity. The motor program is driven by oscillatory calcium signaling in the intestine. Proton fluxes that require sodium-proton exchangers at the apical and basolateral intestinal membranes parallel the intestinal calcium flux. These proton shifts are critical for defecation-associated muscle contraction, nutrient uptake and longevity. How sodium-proton exchangers are activated in time with intestinal calcium oscillation is not known. The <BOLD>p</BOLD>osterior <BOLD>bo</BOLD>dy defecation contraction mutant (pbo-1) e... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176776 Tue, 23 Aug 2011 23:00:00 +0100 5176776 http://www.medworm.com/index.php?rid=5176774&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865589%26dopt%3DAbstract In this study, we clearly demonstrated that mast cells produced PGs in response to the high glucose condition and induced adipocyte differentiation and possibly obesity. This is the first study that provides evidence for a novel role of mast cells in adipogenesis via PPAR© activation. PMID: 21865589 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176774 Tue, 23 Aug 2011 23:00:00 +0100 5176774 http://www.medworm.com/index.php?rid=5176770&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21865590%26dopt%3DAbstract Authors: Dupont-Versteegden EE, Waters C Abstract NA. PMID: 21865590 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5176770 Tue, 23 Aug 2011 23:00:00 +0100 5176770 http://www.medworm.com/index.php?rid=5104205&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21813709%26dopt%3DAbstract In this study, we show that NKCC1 activity in gliomas requires the WNK3 kinase. Western blots of patient biopsies and patient-derived cell lines shows prominent expression of Ste-20-related, proline-alanine rich kinase (SPAK), oxidative stress response kinase (OSR1), and WNK family members 1, 3, and 4. Of these, only WNK3 colocalized and co-immunoprecipitated with NKCC1 upon changes in cell volume. Stable knockdown of WNK3 using specific shRNA constructs completely abolished NKCC1 activity, as measured by the loss of bumetanide-sensitive cell volume regulation. Consequently, WNK3 knockdown cells showed a reduced ability to invade across Transwell barriers and lacked bumetanide-sensitive migration. This data indicates that WNK3 is an essential regulator of NKCC1 and that WNK3 activates NKCC... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104205 Tue, 02 Aug 2011 23:00:00 +0100 5104205 http://www.medworm.com/index.php?rid=5104204&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21813710%26dopt%3DAbstract Authors: Kyle B, Bradley E, Ohya S, Sergeant GP, McHale NG, Thornbury KD, Hollywood MA We have characterized the native voltage-dependent K(+) (K(v)) current in rabbit urethral smooth muscle cells (RUSMC) and compared its pharmacological and biophysical properties with K(v)2.1 and K(v)2.2 channels cloned from the rabbit urethra and stably expressed in HEK 293 cells (HEKK(v)2.1 and HEKK(v)2.2). RUSMC were perfused with Hanks' solution at 37°C and studied using the patch clamp technique with K+-rich pipette solutions. Cells were bathed in 100 nM penitrem A to block large conductance Ca(2+)-activated K(+) (BK) currents and depolarized to +40 mV for 500 ms to evoke Kv currents. These were unaffected by margatoxin, κ-dendrotoxin or α-dendrotoxin (100 nM, n=3-5), but were blocked by strom... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104204 Tue, 02 Aug 2011 23:00:00 +0100 5104204 http://www.medworm.com/index.php?rid=5104203&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21813711%26dopt%3DAbstract Authors: Cook JL, Singh A, Deharo D, Alam J, Re RN Several transmembrane receptors have been documented to accumulate in nuclei, some as holoreceptors and others as cleaved receptor products. Our prior studies indicate that a population of the 7-transmembrane angiotensin type-1 receptor (AT(1)R) is cleaved in a ligand-augmented manner after which the cytoplasmic, carboxy-terminal cleavage fragment (CF) traffics to the nucleus. In the present report, we determine the precise cleavage site within the AT(1)R by mass spectrometry and Edman sequencing. In order to evaluate the function of the cleavage fragment distinct from the holoreceptor, we generated a construct encoding the cleavage fragment as an in-frame yellow fluorescent protein fusion. When expressed in cells, the cleavage fragmen... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104203 Tue, 02 Aug 2011 23:00:00 +0100 5104203 http://www.medworm.com/index.php?rid=5104202&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21813712%26dopt%3DAbstract Authors: Serizawa T, Terui T, Kagemoto T, Mizuno A, Shimozawa T, Kobirumaki F, Ishiwata S, Kurihara S, Fukuda N As the dynamic properties of cardiac sarcomeres are markedly changed in response to a length change of even ~0.1 μm, it is imperative to quantitatively measure sarcomere length (SL). Here we show a novel system using quantum dots (QDs) that enables a real-time measurement of the length of a single sarcomere in cardiomyocytes. First, QDs were conjugated with anti-α-actinin antibody, and applied to the sarcomeric Z-discs in isolated skinned cardiomyocytes of the rat. At partial activation, spontaneous sarcomeric oscillations (SPOC) occurred, and QDs provided a quantitative measurement of the length of a single sarcomere over the broad range (i.e., from ~1.6 to ~2.3 μm). It w... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104202 Tue, 02 Aug 2011 23:00:00 +0100 5104202 http://www.medworm.com/index.php?rid=5104213&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795518%26dopt%3DAbstract Authors: Skarra DV, Cornwell T, Solodushko V, Brown A, Taylor MS Organized uterine contractions, including those necessary for parturition, are dependent on calcium entry through voltage-gated calcium channels in myometrial smooth muscle cells. Recent evidence suggests small conductance Ca(2+)-activated potassium channels (K(Ca)2), specifically isoforms K(Ca)2.2 and 2.3, may control these contractions through negative feedback regulation of Ca(2+) entry. We tested whether selective pharmacologic activation of K(Ca)2.2/2.3 channels might depress uterine contractions, providing a new strategy for preterm labor intervention. Western blotting and immunofluorescence microscopy revealed expression of both K(Ca)2.2 and K(Ca)2.3 in the myometrium of non-pregnant (NP) and pregnant (gestation da... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104213 Tue, 26 Jul 2011 23:00:00 +0100 5104213 http://www.medworm.com/index.php?rid=5104212&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795519%26dopt%3DAbstract Authors: Porter AM, Klinge CM, Gobin AS Angiogenesis is an important biological response known to be involved in many physiological and pathophysiological situations. Cellular responses involved in the formation of new blood vessels, such as increases in endothelial cell proliferation, cell migration, and the survival of apoptosis-inducing events, have been associated with vascular endothelial growth factor isoform 165 (VEGF(165)). Current research in the areas of bioengineering and biomedical science has focused on developing polyethylene glycol (PEG) based systems capable of initiating and sustaining angiogenesis in vitro. However, a thorough understanding of how endothelial cells respond at the molecular level to VEGF(165) incorporated into these systems has not yet been established... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104212 Tue, 26 Jul 2011 23:00:00 +0100 5104212 http://www.medworm.com/index.php?rid=5104211&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795520%26dopt%3DAbstract Authors: Haddad LE, Bou Khzam L, Hajjar F, Merhi Y, Sirois MG Several members of the fibroblast growth factor (FGF) family are potent endothelial cell (EC) mitogens and angiogenic factors, and their activities can be mediated by four tyrosine kinase receptors (FGFR1-4). In addition, FGFs can induce the release of inflammatory mediators by ECs and the expression of adhesion molecules at their surface, thereby favoring the recruitment and transvascular migration of inflammatory cells such as neutrophils. Neither the expression nor the biological activities that could be mediated by FGFRs have been investigated on human neutrophils. By biochemical and cytological analyses, we observed that purified circulating human neutrophils from healthy individuals expressed varying levels of FGFRs in... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104211 Tue, 26 Jul 2011 23:00:00 +0100 5104211 http://www.medworm.com/index.php?rid=5104210&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795521%26dopt%3DAbstract PROTEIN PHOSPHATASE 2A MEDIATES RESENSITIZATION OF THE NEUROKININ 1 RECEPTOR. Am J Physiol Cell Physiol. 2011 Jul 27; Authors: Murphy JE, Roosterman D, Cottrell GS, Padilla BE, Feld M, Brand E, Cedron WJ, Bunnett NW, Steinhoff M Activated G protein-coupled receptors are phosphorylated and interact with β-arrestins, which mediate desensitization and endocytosis. Endothelin-converting enzyme -1 (ECE-1) degrades neuropeptides in endosomes and can promote recycling. Although endocytosis, dephosphorylation and recycling are accepted mechanisms of receptor resensitization, a large proportion of desensitized receptors can remain at the cell-surface. We investigated whether reactivation of non-internalized, desensitized (phosphorylated) receptors mediates resensitization of the substa... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104210 Tue, 26 Jul 2011 23:00:00 +0100 5104210 http://www.medworm.com/index.php?rid=5104209&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795522%26dopt%3DAbstract Authors: Zhang X, Yang D, Hughes BA Previous studies identified in retinal pigment epithelial (RPE) cells an M-type K(+) current, which in many other cell types is mediated by channels encoded by KCNQ genes. The aim of this study was to assess the expression of KCNQ genes in the monkey RPE and neural retina. Application of the specific KCNQ channel blocker XE991 eliminated the M-type current in freshly monkey RPE cells, indicating that KCNQ subunits contribute to the underlying channels. RT-PCR analysis revealed the expression of KCNQ1, KCNQ4, and KCNQ5 transcripts in the RPE and all five KCNQ transcripts in the neural retina. At the protein level, KCNQ5 was detected in the RPE, whereas both KCNQ4 and KCNQ5 were found in neural retina. In situ hybridization in frozen monkey retinal sec... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104209 Tue, 26 Jul 2011 23:00:00 +0100 5104209 http://www.medworm.com/index.php?rid=5104208&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795523%26dopt%3DAbstract Authors: Chou FP, Xu H, Lee MS, Chen YW, Richards OX, Swanson R, Olson ST, Johnson MD, Lin CY Antithrombin, a major anticoagulant, is robustly transported into extravascular compartments where its target proteases are largely unknown. This serpin was previously detected in human milk as complexes with matriptase, a membrane-bound serine protease broadly expressed in epithelial and carcinoma cells, and under tight regulation by hepatocyte growth factor activator inhibitor (HAI)-1, a transmembrane Kunitz-type serine protease inhibitor that forms heat-sensitive complexes with active matriptase. In the current study, we detect, in addition to matriptase-HAI-1 complexes, heat-resistant matriptase complexes generated by non-transformed mammary, prostate, and epidermal epithelial cells that w... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104208 Tue, 26 Jul 2011 23:00:00 +0100 5104208 http://www.medworm.com/index.php?rid=5104207&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795524%26dopt%3DAbstract Authors: Kleyman TR, Insel PA, Frank M n/a. PMID: 21795524 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104207 Tue, 26 Jul 2011 23:00:00 +0100 5104207 http://www.medworm.com/index.php?rid=5104206&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795525%26dopt%3DAbstract Conclusion: TNFα is a cytokine released in the early stages of sepsis. Besides of a possible transcriptional role: modification of the channel type and/or number, we demonstrated the existence of a rapid, post-transcriptional inhibition of Na(V) by TNFα. The down regulation of the sodium current could be mediated by a PKC induced phosphorylation of the sodium channel thus leading to a significant decrease in muscle excitability. PMID: 21795525 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5104206 Tue, 26 Jul 2011 23:00:00 +0100 5104206 http://www.medworm.com/index.php?rid=5009208&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21734186%26dopt%3DAbstract Authors: Kotlo KU, Hesabi B, Danziger RS MicroRNAs (miRs) are endogenous small RNA molecules that suppress gene expression by binding to complementary sequences in the 3' untranslated regions of their target genes. miRs have been implicated in many diseases, including heart failure, ischemic heart disease, hypertension, cardiac hypertrophy and cancers. Nitric oxide (NO) and atrial natriuretic peptide (ANP) are potent vasorelaxants whose actions are mediated through receptor guanylyl cyclases and cGMP-dependent protein kinase (cGK). The present study examines miRs in signaling by ANP and NO in vascular smooth muscle cells. miRNA microarray analysis was performed on human vascular smooth muscle cells (HVSMC) treated with ANP (10nM, 4hrs) and S-nitroso-N-acetylpenicillamine (SNAP) (100µM... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5009208 Tue, 05 Jul 2011 23:00:00 +0100 5009208 http://www.medworm.com/index.php?rid=5009207&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21734187%26dopt%3DAbstract Authors: Re RN None. PMID: 21734187 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5009207 Tue, 05 Jul 2011 23:00:00 +0100 5009207 http://www.medworm.com/index.php?rid=5009206&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21734188%26dopt%3DAbstract Authors: Liu D, Ji L, Tong X, Pan B, Han JY, Huang Y, Chen YE, Pennathur S, Zhang Y, Zheng L High-density lipoprotein (HDL) can induce cyclooxygenase-2 (COX-2) expression and prostacyclin I-2 (PGI-2) release in endothelial cells to exert multiple antiatherogenic functions. This effect has been attributed mainly to the role of sphingosine-1-phosphate (S1P) integrated in HDL. However, whether apolipoprotein A-I (apoA-I), the major apolipoprotein of HDL, could induce COX-2 expression and PGI-2 release still remains unclear. In the present study, we selectively delipidated HDL, and confirmed that apoA-I could facilitate COX-2 expression and PGI-2 production in human umbilical vein endothelial cells (HUVECs). ApoA-I, but not trypsinized apoA-I, induced COX-2 expression in a time- and dose-d... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5009206 Tue, 05 Jul 2011 23:00:00 +0100 5009206 http://www.medworm.com/index.php?rid=5009205&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21734189%26dopt%3DAbstract In this study, we used alanine (Ala) linker scanning to pinpoint the residues in the proximal linker domain involved in regulation of NCX1 by PLM. Transfection of HEK293 cells with WT NCX1 or its alanine mutants but not empty vector resulted in NCX1 current (I(NaCa)). Co-expression of PLM with WT NCX1 inhibited I(NaCa). Mutating residues 248-252 (PASKT) or 300-304 (QKHPD) in WT NCX1 to Ala resulted in loss of inhibition of I(NaCa) by PLM. By contrast, inhibition of I(NaCa) by PLM was preserved when residues 238-242, 243-247, 253-257, 258-262, 263-267, 305-309, 310-314, 315-319, 320-324 or 325-329 were mutated to Ala. While mutating residue 301 to alanine completely abolished PLM inhibition, mutation of any single residue 250-252, 300, or 302-304 resulted in partial reduction in inhibition.... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5009205 Tue, 05 Jul 2011 23:00:00 +0100 5009205 http://www.medworm.com/index.php?rid=5009204&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21734190%26dopt%3DAbstract Authors: Mongin AA, Hyzinski-Garcia MC, Vincent MY, Keller RW Here we report and validate a simple method for measuring intracellular activities of glial glutamine synthetase (GS) and glutaminase (GLNase) in intact glial cells. These enzymes are responsible for glutamate and glutamine recycling in the brain, where glutamate and glutamine transport from the blood stream is strongly limited by the blood-brain barrier. The intracellular levels of glutamate and glutamine are dependent on activities of numerous enzymatic processes, including (i) cytosolic production of glutamine from glutamate by GS, (ii) production of glutamate from glutamine by GLNase that is primarily localized between mitochondrial membranes, and (iii) mitochondrial conversion of glutamate to the TCA intermediate α-ket... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5009204 Tue, 05 Jul 2011 23:00:00 +0100 5009204 http://www.medworm.com/index.php?rid=5009203&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21734191%26dopt%3DAbstract Authors: Sung TS, Jeon JP, Kim BJ, Hong CS, Kim SY, Kim J, Jeon JH, Kim HJ, Suh CK, Kim SJ, So I Canonical transient receptor potential (TRPC) channels are Ca(2+)-permeable, nonselective cation channels that are widely expressed in numerous cell types. Here, we demonstrate a new mechanism of TPRC isofom 5 (TRPC5) regulation, via cAMP signaling via G s. Monovalent cation currents in HEK293 cells transfected with TRPC5 were induced by G protein activation with intracellular perfusion of GTPγS or by muscarinic stimulation. This current could be inhibited by a membrane permeable analogue of cAMP, 8-Br-cAMP, by isoproterenol, by a constitutively active form of Gαs (Gαs (Q227L)) and by forskolin. These inhibitory effects were blocked by the protein kinase A (PKA) inhibitors, KT-5720 and H... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5009203 Tue, 05 Jul 2011 23:00:00 +0100 5009203 http://www.medworm.com/index.php?rid=5009202&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21734192%26dopt%3DAbstract Authors: Takeda Y, Amano A, Noma A, Nakamura Y, Fujimoto S, Inagaki N Glucagon-like peptide-1 (GLP-1) elevates intracellular concentration of cAMP ([cAMP]) and facilitates glucose-dependent insulin secretion in pancreatic β-cells. There has been much evidence to suggest that multiple key players such as the GLP-1 receptor, G(s) protein, adenylate cyclase (AC), phosphodiesterase (PDE), and intracellular Ca(2+) concentration ([Ca(2+)]) are involved in the regulation of [cAMP]. However, because of complex interactions between these signaling factors, the kinetics of the reaction cascade as well as the activities of ACs and PDEs have not been determined in pancreatic β-cells. We have constructed a minimal mathematical model of GLP-1 receptor signal transduction based on experimental find... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5009202 Tue, 05 Jul 2011 23:00:00 +0100 5009202 http://www.medworm.com/index.php?rid=5009209&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21715701%26dopt%3DAbstract Authors: Hoppe T Folding and stability of all proteins (the proteome) is essential for cells and organisms throughout their lifetime. Eukaryotic cells possess a complex protein quality control (PQC) network that balances synthesis, folding, translocation, assembly/disassembly, and degradation of proteins to adjust protein biogenesis to the demands of growth, differentiation, environmental stress, and aging. This protein homeostasis, or proteostasis, protects the cellular proteome against acute and permanent challenges by intrinsic and environmental proteotoxic stress conditions (1). The maintenance of proteostasis involves molecular chaperones and proteolytic systems to refold or degrade unfolded proteins, respectively. Molecular chaperones have diverse roles in the regulation of prote... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=5009209 Tue, 28 Jun 2011 23:00:00 +0100 5009209 http://www.medworm.com/index.php?rid=4912761&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21653897%26dopt%3DAbstract In this study, we tested the hypothesis that mitochondria-derived ROS (mtROS) regulate EC migration. In cultured human umbilical endothelial cells (HUVEC), VEGF increased mitochondrial metabolism, promoted mtROS production, and induced cell migration. Either the targeted mitochondrial delivery of the antioxidant, vitamin E (Mito-Vit-E), or depletion of mitochondrial DNA (mtDNA) abrogated VEGF-mediated mtROS production. Overexpression of mitochondrial catalase also inhibited VEGF induced mitochondrial metabolism, Rac activation and cell migration. Furthermore, these interventions suppressed VEGF-stimulated EC migration and blocked Rac1 activation in endothelial cells. Constitutively active Rac1 reversed Mito-Vit-E- induced inhibition of EC migration. Mito-Vit-E also attenuated carotid arter... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912761 Tue, 07 Jun 2011 23:00:00 +0100 4912761 http://www.medworm.com/index.php?rid=4912760&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21653898%26dopt%3DAbstract In conclusion, the characteristics of TRPA1 we have delineated suggest that it might play a unique role in nociception. PMID: 21653898 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912760 Tue, 07 Jun 2011 23:00:00 +0100 4912760 http://www.medworm.com/index.php?rid=4912759&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21653899%26dopt%3DAbstract Authors: Pinilla-Tenas JJ, Sparkman BK, Shawki A, Illing AC, Mitchell CJ, Zhao N, Liuzzi JP, Cousins RJ, Knutson MD, Mackenzie B Recent studies have shown that overexpression of the transmembrane protein Zip14 stimulates the cellular uptake of zinc and nontransferrin-bound iron (NTBI). Here, we directly tested the hypothesis that Zip14 transports free zinc, iron and other metal ions by using the Xenopus laevis oocyte heterologous expression system, and use of this approach also allowed us to characterize the functional properties of Zip14. Expression of mouse Zip14 in RNA-injected oocytes stimulated the uptake of (55)Fe in the presence of L-ascorbate but not nitrilotriacetic acid, indicating that Zip14 is an iron transporter specific for ferrous ion (Fe(2+)) over ferric ion (Fe(3+)). Z... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912759 Tue, 07 Jun 2011 23:00:00 +0100 4912759 http://www.medworm.com/index.php?rid=4912758&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21653900%26dopt%3DAbstract Authors: Rahimzadeh J, Meng F, Sachs F, Wang J, Verma D, Hua SZ The mechanical stress due to shear flow has profound effects on cell proliferation, transport, gene expression, and apoptosis. The mechanisms for flow sensing and transduction are unclear but it is postulated that fluid flow pulls upon the apical surface and the resulting stress is eventually transmitted through the cytoskeleton to adhesion plaques on the basal surface. Here we report a direct observation of this flow-induced stress in the cytoskeleton in living cells using a parallel plate microfluidic chip with a FRET based mechanical stress sensor in actinin. The sensing cassette was genetically inserted into the cytoskeletal host protein and transfected into MDCK cells. A shear stress of 10 dyn/cm(2) resulted in a rapi... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912758 Tue, 07 Jun 2011 23:00:00 +0100 4912758 http://www.medworm.com/index.php?rid=4912757&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21653901%26dopt%3DAbstract Authors: Butler SM, Abrassart JM, Hubbell MC, Adeoye O, Semotiuk AJ, Williams JM, Mata-Greenwood E, Khorram O, Pearce WJ The present study explores the hypothesis that arterial smooth muscle cells are organized into layers with similar phenotypic characteristics that vary with the relative position between the lumen and the adventitia due to transmural gradients in vasotrophic factors. A corollary hypothesis is that VEGF is a factor that helps establish transmural variations in smooth muscle phenotype. Organ culture of endothelium-denuded ovine carotid arteries with 3 ng/ml VEGF-A165 for 24 hours differentially and significantly influenced potassium-induced (55% increase) and stretch-induced (36% decrease) stress-strain relations in adult (n=18) but not term fetal (n=21) arteries, sugg... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912757 Tue, 07 Jun 2011 23:00:00 +0100 4912757 http://www.medworm.com/index.php?rid=4912756&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21653902%26dopt%3DAbstract This study thus identifies a new mechanism by which anti-adhesion treatment may constitute a potential therapy for tissue edema. PMID: 21653902 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912756 Tue, 07 Jun 2011 23:00:00 +0100 4912756 http://www.medworm.com/index.php?rid=4912765&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21633077%26dopt%3DAbstract Authors: Sobolewski P, Kandel J, Klinger AL, Eckmann DM Gas embolism is a serious complication of decompression events and clinical procedures, but the mechanism of resulting injury remains unclear. Previous work has demonstrated that contact between air microbubbles and endothelial cells causes a rapid intracellular calcium transient and can lead to cell death. Here we examined the mechanism responsible for the calcium rise. Single air microbubbles (50-150 μm), trapped at the tip of a micropipette, were micromanipulated into contact with individual human umbilical vein endothelial cells (HUVECs) loaded with Fluo-4 (a fluorescent calcium indicator). Changes in intracellular calcium were then recorded via epifluorescence microscopy. First, we confirmed that HUVECs rapidly respond to ai... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912765 Tue, 31 May 2011 23:00:00 +0100 4912765 http://www.medworm.com/index.php?rid=4912764&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21633078%26dopt%3DAbstract Authors: Hasegawa T, Azlina A, Javkhlan P, Yao C, Akamatsu T, Hosoi K Aquaporin-5 (AQP5), a water channel, plays key roles in salivary secretion. The novel phosphorylation of AQP5 was investigated by using human salivary gland (HSG) cells and mouse salivary glands. In the HSG cells stably transfected with a wild-type mouse AQP5 construct, a protein band immunoreactive with antibody against phosphorylated PKA (pPKA) substrate was detected in the AQP5 immunoprecipitated sample; and its intensity was enhanced by short-term treatment of the cells with 8-bromo-cAMP, forskolin or PMA, but not by that with A23187 calcium ionophore. Such enhancement was inhibited in the presence of H-89, a PKA inhibitor. An AQP5 mutant (AQP5-T259A) expressed by transfection of HSG cells was not recognized by a... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912764 Tue, 31 May 2011 23:00:00 +0100 4912764 http://www.medworm.com/index.php?rid=4912763&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21633079%26dopt%3DAbstract Authors: Dipolo R, Beauge L The Na(+)/Ca(2+) exchanger, a major mechanism by which cells extrude calcium, is involved in several physiological and physiopathological interactions. In this work we have used the dialyzed squid giant axon to study the effects of two oxidants, SIN-1 buffered peroxynitrite and hydrogen peroxide (H(2)O(2)), on the Na(+)/Ca(2+) exchanger in the absence and presence of MgATP up-regulation. The results show that oxidative stress induced by peroxynitrite and hydrogen peroxide inhibits the Na(+)/Ca(2+) exchanger by impairing the Ca(2+)(i)-regulatory sites, leaving unharmed the intracellular Na(+) and Ca(2+) transporting sites. This effect is efficiently counteracted by the presence of MgATP and by intracellular alkalinization, conditions that also protect H(+)(i)... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912763 Tue, 31 May 2011 23:00:00 +0100 4912763 http://www.medworm.com/index.php?rid=4912762&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21633080%26dopt%3DAbstract Authors: Bankhead P, Scholfield CN, Curtis TM, McGeown JG Studies concerning the physiological significance of Ca(2+) sparks often depend upon the detection and measurement of large populations of events in noisy microscopy images. Automated detection methods have been developed to quickly and objectively distinguish potential sparks from noise artifacts. However, previously described algorithms are not suited to the reliable detection of sparks in images where the local baseline fluorescence and noise properties can vary significantly, and risk introducing additional bias when applied to such datasets. Here, we describe a new, conceptually straightforward approach to spark detection in linescans that addresses this issue by combining variance stabilization with local baseline subtract... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912762 Tue, 31 May 2011 23:00:00 +0100 4912762 http://www.medworm.com/index.php?rid=4912774&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613604%26dopt%3DAbstract Authors: Burkewitz K, Choe K, Strange K Proteostasis is defined as the homeostatic mechanisms that maintain the function of all cytoplasmic proteins. We recently demonstrated that the capacity of the proteostasis network is a critical factor that defines the limits of cellular and organismal survival in hypertonic environments. The current studies were performed to determine the extent of protein damage induced by cellular water loss. Using worm strains expressing fluorescently tagged foreign and endogenous proteins and proteins with temperature sensitive point mutations, we demonstrate that hypertonic stress causes aggregation and misfolding of diverse proteins in multiple cell types. Protein damage is rapid. Aggregation of a polyglutamine GFP reporter is observable with <1 h of hy... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912774 Tue, 24 May 2011 23:00:00 +0100 4912774 http://www.medworm.com/index.php?rid=4912773&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613605%26dopt%3DAbstract Authors: Enyeart JJ, Liu H, Enyeart JA Bovine adrenocortical cells express bTREK-1 K(+) channels that are inhibited by Angiotensin II (AngII) through a Gq-coupled receptor by separate Ca(2+) and ATP-hydrolysis-dependent signaling pathways. Whole cell and single patch clamp recording from adrenal zona fasciculata (AZF) cells were used to characterize Ca(2+)-dependent inhibition of bTREK-1. In whole cell recordings with pipette solutions containing 0.5 mM EGTA and no ATP, the Ca(2+) ionophore ionomycin (1μM) produced a transient inhibition of bTREK-1 that reversed spontaneously within minutes. At higher concentrations, ionomycin (5-10μM) produced a sustained inhibition of bTREK-1 that was reversible upon washing, even in the absence of hydrolyzable [ATP](i). BAPTA was much more effecti... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912773 Tue, 24 May 2011 23:00:00 +0100 4912773 http://www.medworm.com/index.php?rid=4912772&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613606%26dopt%3DAbstract Authors: Cruz-Rangel S, Melo Z, Vazquez N, Meade P, Bobadilla NA, Pasantes-Morales H, Gamba G, Mercado A With-no-lysine kinase 3 (WNK3) is a member of a subfamily of serine/threonine kinases that modulate the activity of the electroneutral cation-coupled chloride cotransporters. WNK3 activates NKCC1/2 and NCC and inhibits the KCCs. Four splice variants are generated from the WNK3 gene. Our previous studies focused on the WNK3-18a variant. However, it has been suggested that other variants could have different effects on the cotransporters. Thus, the present study was designed to define the effects of all WNK3 variants upon members of the SLC12 family. By RT-PCR from a fetal brain library, exons 18b and 22 were separately amplified and subcloned into the original WNK3-18a or catalytical... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912772 Tue, 24 May 2011 23:00:00 +0100 4912772 http://www.medworm.com/index.php?rid=4912771&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613607%26dopt%3DAbstract RECONSTITUTION OF LYSOSOMAL NAADP-TRP-ML1 SIGNALING PATHWAY AND ITS FUNCTION IN TRP-ML1-/- CELLS. Am J Physiol Cell Physiol. 2011 May 25; Authors: Zhang F, Xu M, Han WQ, Li PL It is well known that the mutation of TRP-ML1 (mucolipin-1) causes mucolipidosis IV, a lysosomal storage disease. Given that lysosomal NAADP-Ca(2+) release channel activity is associated with TRP-ML1, the present study was designed to test the hypothesis that NAADP regulates lysosome function via activation of TRP-ML1 channel activity. Using lysosomal preparations from wild-type (TRP-ML1(+/+)) human fibroblasts, channel reconstitution experiments demonstrated that NAADP (0.01 -1.0 µM) produced a concentration-dependent increase in TRP-ML1 channel activity. This NAADP-induced activation of TRP-ML1 channel... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912771 Tue, 24 May 2011 23:00:00 +0100 4912771 http://www.medworm.com/index.php?rid=4912770&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613608%26dopt%3DAbstract Authors: Arcangeli A, Yuan JX N/A. PMID: 21613608 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912770 Tue, 24 May 2011 23:00:00 +0100 4912770 http://www.medworm.com/index.php?rid=4912769&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613609%26dopt%3DAbstract Authors: Huang WY, Xie W, Guo X, Li F, Jose PA, Chen SY Response gene to complement 32 (RGC-32) is activated by TGF-β and plays an important role in smooth muscle cell (SMC) differentiation from neural crest Monc-1 cells. The molecular mechanism governing TGF-β activation of RGC-32, however, remains to be determined. The present studies indicate that TGF-β regulates RGC-32 gene transcription. Sequence analysis revealed a Smad binding element (SBE) located in the region from -1344 to -1337 bp upstream of the transcription start site of RGC-32 gene. A polyomavirus enhancer activator (PEA3) binding site is adjacent to the SBE. Mutation at either SBE or PEA3 site significantly inhibited RGC-32 promoter activity. Mutations at both sites completely abolished TGF-β-induced promoter activi... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912769 Tue, 24 May 2011 23:00:00 +0100 4912769 http://www.medworm.com/index.php?rid=4912768&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613610%26dopt%3DAbstract Authors: Deliu E, Tica AA, Motoc D, Brailoiu GC, Brailoiu E Angiotensin II is a modulator of myometrial activity; both AT(1) and AT(2) receptors are expressed in myometrium. Since in other tissues angiotensin II has been reported to activate intracellular receptors, we assessed the effects of intracellular administration of angiotensin II via microinjection on myometrium, using calcium imaging. Intracellular injection of angiotensin II increased cytosolic Ca(2+) concentration, [Ca(2+)](i), in myometrial cells in a dose-dependent manner. The effect was abolished by the AT(1) receptor antagonist losartan, but not by the AT(2) receptor antagonist PD-123319. Disruption of endo/lysosomal system, but not that of Golgi apparatus prevented the angiotensin II-induced increase in [Ca(2+)](i). Bl... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912768 Tue, 24 May 2011 23:00:00 +0100 4912768 http://www.medworm.com/index.php?rid=4912767&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613611%26dopt%3DAbstract This study uses rat horizontal brainstem slices, patch-clamp electrophysiology and fluorescent Ca(2+) imaging to test the hypothesis that a direct Ca(2+) entrance into glutamatergic terminals through active presynaptic non-α7 or α7 nAChR-mediated ion channels is sufficient to trigger synaptic glutamate release in subsets of caudal NTS neurons. The results of this study demonstrate that in the continuous presence of 0.3 κM tetrodotoxin, a selective blocker of voltage-activated Na(+) ion channels, facilitation of synaptic glutamate release by activation of presynaptic nAChRs (detected as an increase in the frequency of miniature excitatory postsynaptic currents) requires external Ca(2+), but does not require activation of presynaptic Ca(2+) stores and presynaptic high- and low-threshold v... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912767 Tue, 24 May 2011 23:00:00 +0100 4912767 http://www.medworm.com/index.php?rid=4912766&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21613612%26dopt%3DAbstract Authors: Pirkmajer S, Chibalin AV Serum starvation is one of the most frequently performed procedures in molecular biology and there are literally thousands of research papers reporting its use. In fact, this method has become so ingrained in certain areas of research that reports often simply state that cells were serum-starved without providing any factual details as to how the procedure was carried out. Even so, we quite obviously lack unequivocal terminology, standard protocols and perhaps most surprisingly, a common conceptual basis when performing serum starvation. Such inconsistencies not only hinder inter-study comparability, but can lead to opposing and inconsistent experimental results. Although it is frequently assumed that serum starvation reduces basal activity of cells, a... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4912766 Tue, 24 May 2011 23:00:00 +0100 4912766 http://www.medworm.com/index.php?rid=4866059&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593445%26dopt%3DAbstract Authors: Bourcier C, Griseri P, Grépin R, Bertolotto C, Mazure N, Pagès G Most melanoma cells are characterized by the V600E mutation in B-Raf kinase. This mutation leads to increased expression of Interleukin (CXCL8) which plays a key role in cell growth and angiogenesis. Thus, CXCL8 appears to be an interesting therapeutic target. Hence, we performed vaccination of mice with GST-CXCL8 which results in a reduced incidence of syngenic B16 melanoma cell xenograft tumors. We next addressed the molecular mechanisms responsible for aberrant CXCL8 expression in melanoma. The CXCL8 mRNA contains multiples AU-rich sequences (AREs) that modulate mRNA stability through the binding of Tristetraprolin (TTP). Melanoma cell lines express very low TTP levels. We therefore hypothesized that the ver... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866059 Tue, 17 May 2011 23:00:00 +0100 4866059 http://www.medworm.com/index.php?rid=4866058&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593446%26dopt%3DAbstract Authors: Lang E, Qadri SM, Zelenak C, Gu S, Rotte A, Draeger A, Lang F Blebbistatin, a myosin II inhibitor, interferes with myosin-actin interaction and microtubule assembly. By influencing cytoskeletal dynamics blebbistatin counteracts apoptosis of several types of nucleated cells. Even though lacking nuclei and mitochondria, erythrocytes may undergo suicidal cell death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine exposure at the cell surface. Triggers of eryptosis include energy depletion and osmotic shock, which enhance cytosolic Ca(2+)-activity with subsequent Ca(2+)-sensitive cell shrinkage and cell membrane scrambling. The present study explored the effect of blebbistatin on eryptosis. Cell membrane scrambling was est... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866058 Tue, 17 May 2011 23:00:00 +0100 4866058 http://www.medworm.com/index.php?rid=4866057&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593447%26dopt%3DAbstract Authors: Lee JM, Davis FM, Roberts-Thomson SJ, Monteith GR The Ca(2+) signal has major roles in cellular processes important in tumorigenesis, including migration, invasion, proliferation and apoptotic sensitivity. New evidence has revealed that, aside from altered expression and effects on global cytosolic free Ca(2+) levels via direct transport of Ca(2+), some Ca(2+) pumps and channels are able to contribute to tumorigenesis via mechanisms that are independent of their ability to transport Ca(2+) or effect global Ca(2+) homeostasis in the cytoplasm. Here, we review some of the most recent studies that present evidence of altered Ca(2+) channel or pump expression in tumorigenesis, and discuss the importance and complexity of localized Ca(2+) signaling in events critical for tumor form... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866057 Tue, 17 May 2011 23:00:00 +0100 4866057 http://www.medworm.com/index.php?rid=4866056&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593448%26dopt%3DAbstract Authors: Ferry AL, Vanderklish PW, Dupont-Versteegden EE Cold-inducible RNA binding protein (RBM3) is suggested to be involved in the regulation of skeletal muscle mass. Cell death pathways are implicated in the loss of muscle mass and therefore the role of RBM3 in muscle apoptosis in C(2)C(12) myoblasts was investigated in this study. RBM-3 overexpression was induced by either cold shock (32°C exposure for 6 hours) or transient transfection with a myc-tagged RBM3 expression vector. Cell death was induced by H(2)O(2) (1000 μM) or Staurosporine (StSp, 5μM) and it was shown that cold shock and RBM3 transfection were associated with attenuation of morphological changes and an increase in cell viability compared to normal temperature or empty vector, respectively. No changes in prolifer... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866056 Tue, 17 May 2011 23:00:00 +0100 4866056 http://www.medworm.com/index.php?rid=4866055&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593449%26dopt%3DAbstract Authors: Stewart AK, Shmukler BE, Vandorpe DH, Reimold F, Heneghan JF, Nakakuki M, Akhavein A, Ko SB, Ishiguro H, Alper SL The secretin-stimulated human pancreatic duct secretes HCO(3)(-) -rich fluid essential for normal digestion. Optimal stimulation of pancreatic HCO(3)(-) secretion likely requires coupled activities of the CFTR anion channel and apical SLC26 Cl(-)/HCO(3)(-) exchangers. However, whereas stimulated human and guinea pig (gp) pancreatic ducts secrete ~140 mM HCO(3)(-) or more, mouse and rat ducts secrete ~ 40-70 mM HCO(3)(-) . Moreover, the axial distribution and physiological roles of SLC26 anion exchangers in pancreatic duct secretory processes remain controversial, and may vary among mammalian species. Thus, the property of high HCO(3)(-) secretion shared by human an... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866055 Tue, 17 May 2011 23:00:00 +0100 4866055 http://www.medworm.com/index.php?rid=4866054&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593450%26dopt%3DAbstract Authors: Tanner BC, Miller MS, Miller BM, Lekkas P, Irving TC, Maughan DW, Vigoreaux JO The indirect flight muscle (IFM) of insects is characterized by a near crystalline myofilament lattice structure that likely evolved to achieve high power output. In Drosophila IFM, the myosin rod binding protein flightin plays a crucial role in thick filament organization and sarcomere integrity. Here we investigate the extent to which the C-terminus of flightin contributes to IFM structure and mechanical performance using transgenic Drosophila (fln(ΔC44)) expressing a truncated flightin lacking the 44 C-terminal amino acids. Electron microscopy and x-ray diffraction measurements show decreased myofilament lattice order in the fln(ΔC44) line compared to control, a transgenic flightin-null rescued... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866054 Tue, 17 May 2011 23:00:00 +0100 4866054 http://www.medworm.com/index.php?rid=4866053&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593451%26dopt%3DAbstract This study explored the role of endogenously formed adenosine in modulating NF-κB activity, cytokine/chemokine release from murine Treg and Teff cells including key enzymes/purinergic receptors of extracellular ATP catabolism. Stimulating murine splenocytes and CD4(+) T-cells with anti-CD3/anti-CD28, significantly upregulated activated NF-κB in CD73(-/-) T-cells (WT: 4.36 ± 0.21, CD73(-/-): 6.58 ± 0.75; n=4; p=0.029). This was associated with an augmented release of proinflammatory cytokines IL-2, TNF-α and IFN-γ. Similar changes were observed with the CD73 inhibitor APCP (50μM) on NF-κB and IFN-γ in WT CD4(+) T-cells. Treatment of stimulated CD4(+) T-cells with adenosine [25 μM] potently reduced IFN-γ release which is mediated by adenosine A2a receptors (A2aR). AMP [50 μM] als... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866053 Tue, 17 May 2011 23:00:00 +0100 4866053 http://www.medworm.com/index.php?rid=4866052&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593452%26dopt%3DAbstract Authors: Llanzano L, Lei T, Okamura K, Giral H, Caldas YA, Masihzadeh O, Gratton E, Levi M, Blaine J The kidney is a key regulator of phosphate homeostasis. There are two predominant renal sodium phosphate cotransporters, NaPi2a and NaPi2c. Both are regulated by parathyroid hormone (PTH) which decreases the abundance of the NaPi cotransporters in the apical membrane of renal proximal tubule cells. The time course of PTH-induced removal of the two cotransporters from the apical membrane however is markedly different for NaPi2a compared to NaPi2c. In animals and in cell culture PTH treatment results in almost complete removal of NaPi2a from the BB within one hour whereas for NaPi2c this process in not complete until 4 to 8 hours after PTH treatment. The reason for this is poorly understo... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866052 Tue, 17 May 2011 23:00:00 +0100 4866052 http://www.medworm.com/index.php?rid=4866051&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21593453%26dopt%3DAbstract Authors: Gunaje JJ, Bahrami AJ, Schwartz SM, Daum G, Mahoney WM Regulator of G-protein signaling (RGS) proteins, and notably members of the RGS-R4 subfamily, control vasocontractility by accelerating the inactivation of Gα-dependent signaling. RGS5 is the most highly and differently expressed RGS-R4 subfamily member in arterial smooth muscle. Expression of RGS5 first appears in pericytes during development of the afferent vascular tree, suggesting that RGS5 is a good candidate for a regulator of arterial contractility and, perhaps, for determining the mass of the smooth muscle coats required to regulate blood flow in the branches of the arterial tree. Consistent with this hypothesis, using cultured vascular smooth muscle cells (SMCs), we demonstrate RGS5 over-expression inhibits G-pro... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866051 Tue, 17 May 2011 23:00:00 +0100 4866051 http://www.medworm.com/index.php?rid=4866066&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562303%26dopt%3DAbstract Authors: Chow JY, Estrema C, Orneles T, Dong X, Barrett KE, Dong H Ca-sensing receptor (CaSR), a member of the G-protein coupled receptor family, regulates the synthesis of parathyroid hormone in response to changes in serum Ca(2+) concentrations. The functions of CaSR in human vascular smooth muscle cells are largely unknown. Here, we sought to study CaSR activation and the underlying molecular mechanisms in human aortic smooth muscle cells (HASMC). Extracellular Ca(2+) ([Ca(2+)](o)) dose-dependently increased cytosolic free Ca(2+) ([Ca(2+)](cyt)) in HASMC, with a half-maximal response (EC50) of 0.52 mM and a Hill coefficient of 5.50. CaSR was expressed in HASMC, and [Ca(2+)](o)-induced [Ca(2+)](cyt) rise was abolished by dominant negative mutants of CaSR. Induction of [Ca(2+)](cyt) w... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866066 Tue, 10 May 2011 23:00:00 +0100 4866066 http://www.medworm.com/index.php?rid=4866065&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562304%26dopt%3DAbstract Authors: Clark KA, Lesage-Horton H, Zhao C, Beckerle MC, Sw. DM Muscle LIM protein (MLP) can be found at the Z-disc of sarcomeres where it is hypothesized to be involved in sensing muscle stretch. Loss of murine MLP results in dilated cardiomyopathy and mutations in human MLP lead to cardiac hypertrophy, indicating a critical role for MLP in maintaining normal cardiac function. Loss of MLP in Drosophila (mlp84B) also leads to muscle dysfunction, providing a model system to examine MLP's mechanism of action. Mlp84B-null flies that survive to adulthood are not able to fly or beat their wings. Transgenic expression of the mlp84B gene in the Mlp84B-null background rescues flight ability and restores wing beating ability. Mechanical analysis of skinned flight muscle fibers showed a 30% decr... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866065 Tue, 10 May 2011 23:00:00 +0100 4866065 http://www.medworm.com/index.php?rid=4866064&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562305%26dopt%3DAbstract Authors: Murray J, Huss JM Myocyte differentiation involves complex interactions between signal transduction pathways and transcription factors. The estrogen-related receptors (ERRs) regulate energy substrate uptake, mitochondrial respiration and biogenesis and may target structural gene programs in striated muscle. However, ERRα's role in regulating myocyte differentiation is not known. ERRα and PGC-1α are coordinately upregulated with metabolic and skeletal muscle-specific genes early in myogenesis. We analyzed effects of ERRα overexpression and loss of function in myogenic models. In C2C12 myocytes ERRα overexpression accelerated differentiation, whereas XCT790 treatment delayed myogenesis and resulted in myotubes with fewer mitochondria and disorganized sarcomeres. ERRα-/- pr... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866064 Tue, 10 May 2011 23:00:00 +0100 4866064 http://www.medworm.com/index.php?rid=4866063&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562306%26dopt%3DAbstract Authors: Wallace BK, Foroutan S, O'Donnell ME Increased blood-brain barrier (BBB) Na-K-Cl cotransporter activity appears to contribute to cerebral edema formation during ischemic stroke. We have shown previously that inhibition of BBB Na-K-Cl cotransporter activity reduces edema and infarct in the rat middle cerebral artery occlusion (MCAO) model of ischemic stroke. We have also shown that the BBB cotransporter is stimulated by the ischemic factors hypoxia, aglycemia and arginine vasopressin (AVP), although the mechanisms responsible are not well understood. AMP-activated protein kinase (AMPK), a key mediator of cell responses to stress, can be activated by a variety of stresses, including ischemia, hypoxia and aglycemia. Previous studies have shown that the AMPK inhibitor Compound C s... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866063 Tue, 10 May 2011 23:00:00 +0100 4866063 http://www.medworm.com/index.php?rid=4866062&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562307%26dopt%3DAbstract Authors: Koltsova SV, Platonova A, Maksimov GV, Mongin AA, Grygorczyk R, Orlov SN Purinergic receptors activate diverse signaling cascades and regulate the activity of cell volume-sensitive ion transporters. Yet, the effects of ATP and other agonists of P2 receptors on cell volume dynamics are only scarcely studied. In the present work, we used the recently-developed dual-image surface reconstruction technique to explore the influence of purinergic agonists on cell volume in the C11-MDCK cell line resembling intercalated cells from kidney collecting ducts. Unexpectedly, we found that ATP and UTP triggered very robust (55-60%) cell shrinkage that lasted up to 2 hr after agonist washout. Purinergic regulation of cell volume required increases in intracellular Ca(2+), and could be partial... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866062 Tue, 10 May 2011 23:00:00 +0100 4866062 http://www.medworm.com/index.php?rid=4866061&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562308%26dopt%3DAbstract Authors: Hu X, Wei L, Taylor TM, Wei J, Zhou X, Wang JA, Yu SP Transplantation using stem cells including bone marrow mesenchymal stem cells (BMSCs) is emerging as a potential regenerative therapy after ischemic attacks in the heart and brain. The migration capability of transplanted cells is a critical cellular function for tissue repair. Based on our recent observations that hypoxic preconditioning (HP) has multiple benefits in improving stem cell therapy and that the potassium Kv2.1 channel acts as a promoter for focal adhesion kinase (FAK) activation and cell motility, the present investigation tested the hypothesis that HP treatment can increase BMSC migration via the mechanism of increased Kv2.1 expression and FAK activities. BMSCs derived from green fluorescent protein (GFP)-tra... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866061 Tue, 10 May 2011 23:00:00 +0100 4866061 http://www.medworm.com/index.php?rid=4866060&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21562309%26dopt%3DAbstract Authors: Arcangeli A The traditional view of cancer as a collection of proliferating cells must be reconsidered, and cancer must be viewed as a "tissue", constituted by both transformed cells and a heterogeneous microenvironment, that tumor cells construct and remodel during the course of multistep tumorigenesis. The "tumor microenvironment" (TM) is formed by mesenchymal, endothelial, immune cells, immersed in a network of extracellular matrix (ECM) proteins and soluble factors. The TM strongly contributes to tumor progression, through long-distance, cell-to-cell or cell-to-matrix signals, which influence different aspects of tumor cell behaviour. Understanding the relationships among the different components of the cancer tissue is crucial to design and develop new therapeutic strateg... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4866060 Tue, 10 May 2011 23:00:00 +0100 4866060 http://www.medworm.com/index.php?rid=4814499&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21525429%26dopt%3DAbstract Authors: Hwang M, Ko JK, Weisleder N, Takeshima H, Ma J We recently discovered that MG53, a muscle-specific TRIM family protein, functions as a sensor of oxidation to nucleate the assembly of cell membrane repair machinery. Our data showed that disulfide bond formation mediated by Cys242 is critical for MG53-mediated translocation of intracellular vesicles toward the injury sites. Here we test the hypothesis that leucine-zipper motifs in the coiled-coil domain of MG53 constitute an additional mechanism that facilitates oligomerization of MG53 during cell membrane repair. Two leucine-zipper motifs in the coiled-coil domain of MG53 (LZ1 - L176/L183/L190/V197 and LZ2 - L205/L212/L219/L226) are highly conserved across the different animal species. Chemical cross-linking studies show that L... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814499 Tue, 26 Apr 2011 23:00:00 +0100 4814499 http://www.medworm.com/index.php?rid=4814498&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21525430%26dopt%3DAbstract RAB27B REGULATES EXOCYTOSIS OF SECRETORY VESICLES IN ACINAR EPITHELIAL CELLS FROM THE LACRIMAL GLAND. Am J Physiol Cell Physiol. 2011 Apr 27; Authors: Chiang L, Ngo J, Schechter JE, Karvar S, Tolmachova T, Seabra MC, Hume AN, Hamm-Alvarez SF Tear proteins are supplied by the regulated fusion of secretory vesicles at the apical surface of lacrimal gland acinar cells, utilizing trafficking mechanisms largely yet uncharacterized. We investigated the role of Rab27b in the terminal release of these secretory vesicles. Confocal fluorescence microscopy analysis of primary cultured rabbit lacrimal gland acinar cells revealed that Rab27b was enriched on the membrane of large subapical vesicles that were significantly colocalized with Rab3D and Myosin5C. Stimulation of cultured acinar ce... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814498 Tue, 26 Apr 2011 23:00:00 +0100 4814498 http://www.medworm.com/index.php?rid=4814497&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21525431%26dopt%3DAbstract Authors: Graham S, Gorin YC, Abboud HE, Ding M, Lee DY, Shi H, Ding Y, Ma R The present study was performed to investigate the underlying mechanism, particularly the roles of reactive oxygen species (ROS) and protein kinase C (PKC) in the diabetes-induced TRPC6 downregulation. We found that high glucose (HG) significantly reduced TRPC6 protein expression in cultured mesangial cells (MCs). TRPC6 protein was also significantly reduced in the glomeruli, but not in the heart or aorta isolated from streptozotocin-induced diabetic rats. In the cultured MCs, H(2)O(2) suppressed TRPC6 protein expression in a dose and time dependent manner, which emulated the HG effect. Catalase as well as superoxide dismutase were able to prevent the inhibitory effect of HG on TRPC6. The antioxidant effect obs... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814497 Tue, 26 Apr 2011 23:00:00 +0100 4814497 http://www.medworm.com/index.php?rid=4814494&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21525432%26dopt%3DAbstract We report therefore for the first time non-invasive mapping of the oxygen-sensing properties of Type I cells within the intact adult mouse CB ex vivo by using multifocal Nipkow disk-based imaging of oxygen-, calcium- and potential-sensitive cellular dyes. Characteristic Type I cell cluster were identified in the compact tissue by immunohistochemistry because of their large cell nuclei combined with positive tyrosine hydroxylase staining. The cellular calcium concentrations in these cell clusters either increased or decreased in response to reduced tissue oxygen concentrations. Under control conditions, cellular potential oscillations were uniform at approximately 0.02 Hz. Under hypoxia-induced membrane depolarization, these oscillations ceased. Simultaneous increases and decreases in poten... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814494 Tue, 26 Apr 2011 23:00:00 +0100 4814494 http://www.medworm.com/index.php?rid=4814493&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21525433%26dopt%3DAbstract This study suggests that CH increases ET-1 expression, thereby elevating PASMC [Ca(2+)](i) and RhoA/ROK activity. As previously demonstrated, elevated [Ca(2+)](i) is required to activate calcineurin which dephosphorylates NFATc3, allowing its nuclear import. Here, we demonstrate that ROK increases actin polymerization, thus providing structural support for NFATc3 nuclear transport. PMID: 21525433 [PubMed - as supplied by publisher] (Source: American Journal of Physiology. Cell Physiology) American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814493 Tue, 26 Apr 2011 23:00:00 +0100 4814493 http://www.medworm.com/index.php?rid=4814492&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21525434%26dopt%3DAbstract MEMBRANE CHOLESTEROL MODULATES THE FLUID SHEAR STRESS RESPONSE OF POLYMORPHONUCLEAR LEUKOCYTES VIA ITS EFFECTS ON MEMBRANE FLUIDITY. Am J Physiol Cell Physiol. 2011 Apr 27; Authors: Zhang X, Hurng J, Rateri DL, Daugherty A, Schmid-Schönbein GW, Shin HY Continuous exposure of polymorphonuclear leukocytes (PMNLs) to circulatory hemodynamics points to fluid flow as a biophysical regulator of their activity. Specifically, fluid flow-derived shear stresses deactivate leukocytes via actions on the conformational activities of proteins on the cell surface. Because membrane properties affect activities of membrane-bound proteins, we hypothesized that changes in the physical properties of cell membranes influence PMNL sensitivity to fluid shear stress. For this purpose, we modified PMN... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814492 Tue, 26 Apr 2011 23:00:00 +0100 4814492 http://www.medworm.com/index.php?rid=4814491&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21525435%26dopt%3DAbstract In this study, we found that mRNA levels of NOX5-S were significantly higher in FLO EA cells than in the normal human esophageal squamous cell line HET-1A or in a Barrett cell line BAR-T. The mRNA levels of NOX5-S were also significantly increased in EA tissues. The data suggest that NOX5-S may be important in the development of EA. Mechanisms of functional regulation of NOX5-S are not fully understood. We show that a small G-protein Rac1 was present in HET-1A, BAR-T cells, and EA cell lines FLO and OE33. Rac1 protein levels were significantly higher in FLO and OE33 cells than in HET-1A or BAR-T cells. Knockdown of Rac1 with Rac1 siRNA significantly decreased acid-induced increase in H(2)O(2) production in FLO EA cells. Overexpression of constitutively active Rac1 significantly increased H... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814491 Tue, 26 Apr 2011 23:00:00 +0100 4814491 http://www.medworm.com/index.php?rid=4814502&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21508333%26dopt%3DAbstract Authors: Elliott J, Zheleznova NN, Wilson PD c-Src is a non-receptor tyrosine kinase whose activity is induced by phosphorylation at Y418 and translocation from the cytoplasm to the cell membrane. Increased activity of c-Src has been associated with cell proliferation, matrix adhesion, motility and apoptosis in tumors. Immunohistochemistry suggested that activated (pY418)-Src activity is increased in cyst-lining ADPKD epithelial cells in human and mouse autosomal dominant polycystic kidney disease (ADPKD). Western blot analysis showed that SKI-606 (Wyeth) is a specific inhibitor of pY(418)-src without demonstrable effects on EGFR or ErbB2 activity in renal epithelia. In vitro studies on mouse collecting duct (mIMCD) cells and human ADPKD cyst-lining epithelial cells showed that SKI-606... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814502 Tue, 19 Apr 2011 23:00:00 +0100 4814502 http://www.medworm.com/index.php?rid=4814501&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21508334%26dopt%3DAbstract Authors: McFarlane C, Gu ZH, Wong ZW, Lau HY, Lokireddy S, Ge X, Mouly V, Butler-Browne G, Gluckman PD, Sharma M, Kambadur R Myostatin, a member of the transforming growth factor-β superfamily, has been implicated in the potent negative regulation of myogenesis in murine models. However, little is known about the mechanism(s) through which human myostatin negatively regulates human skeletal muscle growth. Using human primary myoblast cell lines and recombinant human myostatin protein we show here that myostatin blocks human myoblast proliferation by regulating cell cycle progression through targeted upregulation of p21. We further show that myostatin regulates myogenic differentiation through the inhibition of key myogenic regulatory factors including MyoD, via canonical Smad signalin... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814501 Tue, 19 Apr 2011 23:00:00 +0100 4814501 http://www.medworm.com/index.php?rid=4814500&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21508335%26dopt%3DAbstract Authors: Li J, Liu J, Song J, Wang X, Weiss HL, Townsend CM, Gao T, Evers BM The mammalian target of rapamycin (mTOR) signaling exists in two complexes: mTORC1 and mTORC2. Neurotensin (NT), an intestinal hormone secreted by enteroendocrine (N) cells in the small bowel, has important physiologic effects in the gastrointestinal tract. The human endocrine cell line, BON, abundantly expresses the NT gene, synthesizes and secretes NT in a manner analogous to that of N cells. Here, we demonstrate that the inhibition of mTORC1 by rapamycin (mTORC1 inhibitor), torin1 (both mTORC1 and mTORC2 inhibitor) or shRNA-mediated knockdown of mTOR, RAPTOR and p70S6K increased basal NT release via up-regulating NT gene expression in BON cells. c-Jun activity was increased by rapamycin or torin1 or p70S6K ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814500 Tue, 19 Apr 2011 23:00:00 +0100 4814500 http://www.medworm.com/index.php?rid=4814508&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21490312%26dopt%3DAbstract Authors: Moral-Sanz J, Gonzalez T, Menendez C, David M, Moreno L, Macias A, Cortijo J, Valenzuela C, Perez-Vizcaino F, Cogolludo A Neutral sphingomyelinase (nSMase)-derived ceramide has been proposed as a mediator of hypoxic pulmonary vasoconstriction (HPV), a specific response of the pulmonary circulation. Voltage-gated K(+) (Kv) channels are modulated by numerous vasoactive factors including hypoxia and their inhibition has been involved in HPV. Herein, we have analyzed the effects of ceramide on Kv currents and contractility in rat pulmonary arteries (PA) and in mesenteric arteries (MA). The ceramide analog C6-ceramide inhibited Kv currents present in PA smooth muscle cells (PASMC). Similar effects were obtained after the addition of bacterial sphingomyelinase (SMase), indicating a ... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814508 Tue, 12 Apr 2011 23:00:00 +0100 4814508 http://www.medworm.com/index.php?rid=4814507&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21490313%26dopt%3DAbstract Authors: Garcia J The α2/δ1 and α11.1 subunits are present at a 1:1 ratio in the dihydropyridine receptor (DHPR) from adult skeletal muscle. In contrast, during early myotube development α2/δ1 is present at higher levels than α11.1 and localizes at the ends of the cells, suggesting that α2/δ1 may have a role independent from DHPRs. We sought to identify binding partners of α2/δ1 at a period when levels of α11.1 are low. Analysis of protein complexes in their native configuration established that α2/δ1 may be associating with ATP5b, a subunit of a mitochondrial ATP synthase complex. This interaction was confirmed with fluorescence resonance energy transfer and co-immunoprecipitation. The association of α2/δ1 and ATP5b occurs in intracellular membranes and at the plasma me... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814507 Tue, 12 Apr 2011 23:00:00 +0100 4814507 http://www.medworm.com/index.php?rid=4814505&cid=s_36923_171_f&fid=36923&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21490314%26dopt%3DAbstract Authors: Balaban RS, Koretsky A The measurement of unidirectional rates of reaction, in vivo, using magnetization transfer techniques is a unique capability of nuclear magnetic resonance spectroscopy (NMRS). However, the complicated network of cytosolic reactions as well as the potential existence of small exchanging metabolic pools or enzyme-substrate complexes with poorly defined NMRS properties makes the interpretation of these data difficult. Fromm and Ugurbil, in this issue, discuss using NMRS for analyzing the turnover ATP in muscle, present the impact of cytosolic exchange networks on these measures along with approaches to ameliorate their effects. Herein, we discuss the potential influence of small metabolite pools or enzyme-substrate complexes on magnetization transfer measur... American Journal of Physiology. Cell Physiology journals http://www.medworm.com/rss/comments.php?id=4814505 Tue, 12 Apr 2011 23:00:00 +0100 4814505