MedWorm: Drugs & Pharmacology

Cytotoxic activity of diterpenes and extracts of juniperus brevifolia

Planta Medica — Sat, 17 May 2008 15:54:18 +0100

Planta MedDOI: 10.1055/s-2008-1074529AbstractThe hexane, dichloromethane, acetone and ethanol extracts of the leaves, bark and wood of were subjected to screening against human tumour cells lines from the cervix (HeLa) and larynx (Hep-2) in two different stages of the cell cycle. The dichloromethane and the chloroform-soluble portions of the acetone extracts of the leaves were active against both tumour cell lines. Chemical investigation of one of the most active extracts (dichloromethane extract from leaves) by preparative chromatography afforded compounds . Among these, compounds were isolated for the first time from the genus (18-hydroxyferruginol, 6,7-dehydrototarol and 7α-hydroxytotarol) while and are rare as natural products corresponding to ()- and ()-isomers of 8α-hydroxy-labda-13(16),14-dien-19-yl-coumarate, respectively. The structures of all compounds were established based on various spectral data. The cytotoxic activity was evaluated for the first time for compounds against HeLa and Vero cell lines in lag and log phases of growth. Compound was shown to be active and selective to HeLa in the log phase.[...]© Georg Thieme Verlag KG Stuttgart · New YorkGet connected:Table of contents | Abstract | Full text (Source: Planta Medica)

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Anticomplementary activity of triterpenoids from the whole plant of aceriphyllum rossii against the classical pathway

Planta Medica — Sat, 17 May 2008 15:54:18 +0100

Planta MedDOI: 10.1055/s-2008-1074534AbstractTo provide a better understanding of the anti-complement activity of triterpenoids, seven unusual pentacyclic triterpenoids bearing a carboxyl group at C-27 were evaluated for their anticomplement activities against the classical pathway of the complement system. The triterpenoids were isolated from the whole plant of of the family Saxifragaceae and were determined to be 3α,23-isopropylidenedioxyolean-12-en-27-oic acid (), 3-oxoolean-12-en-27-oic acid (), 3α-hydroxyolean-12-en-27-oic acid (), β-peltoboykinolic acid (), 3α,23-diacetoxyolean-12-en-27-oic acid (), 23-hydroxy-3-oxoolean-12-en-27-oic acid () and aceriphyllic acid A (). Among them, compounds , , and showed significant anticomplement activity on the classical pathway with IC values of 71.4, 98.5, and 180.7 μM, respectively, whereas compounds , , , and were inactive. Our findings suggest that both the ketone at C-3 and the methyl at C-23 in the oleanane triterpenoids with a carboxyl group at C-27 are important for the anticomplement activity against the classical pathway.[...]© Georg Thieme Verlag KG Stuttgart · New YorkGet connected:Table of contents | Abstract | Full text (Source: Planta Medica)

Glucuronidated metabolites of the flavonoid quercetin do not auto-oxidise, do not generate free radicals and do not decrease nitric oxide bioavailability

Planta Medica — Sat, 17 May 2008 15:54:18 +0100

Planta MedDOI: 10.1055/s-2008-1074525AbstractQuercetin, the most abundant flavonoid in the diet, reduces blood pressure and restores endothelial dysfunction in hypertensive animals. However, quercetin (as the aglycone) is usually not present in plasma, but it is rapidly metabolised during absorption by methylation, glucuronidation and sulfation. Depending on the experimental conditions, quercetin can show anti-oxidant or pro-oxidant effects. We have analysed the pro-oxidant effects of quercetin and its methylated (3-methylquercetin or isorhamnetin), sulfated (quercetin 3′-sulfate), glucuronidated (quercetin 3-glucuronide) and methylated plus glucuronidated (isorhamnetin 3-glucuronide) metabolites. Auto-oxidation, O release and NO scavenging were analysed by means of absorption spectra, lucigenin chemiluminescence or superoxide dismutase inhibitable cytochrome C reduction and an amperometric electrode, respectively. The biological activity of NO was tested in rat aortic rings. Quercetin, isorhamnetin and quercetin 3′-sulfate auto-oxidized in aqueous buffer and generated superoxide radical. Quercetin but not the glucuronide scavenged NO. In contrast, the glucuronides were without effect. Quercetin, but not quercetin 3-glucuronide, inhibited the biological activity of NO. These data indicate that, in contrast to quercetin, its main circulating forms, i. e., the glucuronides, do not exert pro-oxidant effects.[...]© Georg Thieme Verlag KG Stuttgart · New YorkGet connected:Table of contents | Abstract | Full text (Source: Planta Medica)

Madecassoside isolated from centella asiatica herbs facilitates burn wound healing in mice

Planta Medica — Sat, 17 May 2008 15:54:18 +0100

Planta MedDOI: 10.1055/s-2008-1074533AbstractThe current study was designed to investigate the effect of madecassoside, the major triterpene in , on burn wound healing and its possible mechanism of action. An oral administration of madecassoside (6, 12, 24 mg/kg) facilitated wound closure in a time-dependent manner and reached its peak effect, nearly completely wound closure, on day 20 in the group receiving the highest dose of 24 mg/kg of madecassoside. Further histopathological analysis revealed that madecassoside alleviated infiltration of inflammatory cells as well as enhanced epithelisation resulting from dermal proliferation of fibroblasts. Madecassoside at higher doses (12 and 24 mg/kg) decreased nitric oxide (NO) levels and malondialdehyde (MDA) content in the burn skin tissue. However, reduced glutathione (GSH) and hydroxyproline levels were increased in the same skin tissue. In addition, madecassoside promoted skin angiogenesis , correlating with our findings that it stimulated endothelial cell growth in a rat aortic ring assay. These data suggest that madecassoside has significant wound-healing activity and is one of the major reasons for the use of herbs in the successful treatment of burn injury. Moreover, the results from the present study indicate that the effect of madecassoside on wound healing may involve several mechanisms including antioxidative activity, collagen synthesis and angiogenesis.[...]© Georg Thieme Verlag KG Stuttgart · New YorkGet connected:Table of contents | Abstract | Full text (Source: Planta Medica)

Growth inhibition of a spectrum of bacterial and fungal pathogens by sulforaphane, an isothiocyanate product found in broccoli and other cruciferous vegetables

Planta Medica — Sat, 17 May 2008 15:54:18 +0100

Planta MedDOI: 10.1055/s-2008-1074520AbstractIn addition to its documented antitumor effects, previous and infectivity experiments have shown that sulforaphane (SFN), an isothiocyanate compound found abundantly in broccoli and other cruciferous vegetables, inhibits the growth of the bacterial pathogen No recent evidence exists, however, on the possible microbial activity of SFN against a broader range of microorganisms, including those that may develop resistance to conventional antibiotics. The aim of this study was to determine the susceptibility patterns of SFN against a wide variety of bacterial and fungal pathogens. Sensitivity testing was done on 28 different microbial species using a modified Kirby-Bauer disk-diffusion method and results were interpreted based on guidelines established by the National Committee for Clinical Laboratory Standards. The broad-spectrum antibiotic, ceftriaxone (CTX), was used as a positive control for antimicrobial inhibition. It was found that 23 out of 28 different microbial species were inhibited by SFN with a minimal inhibitory concentration (MIC) ranging from 1 - 4 μg/mL. Five pathogens - 3 methicillin-resistant (MRSA) isolates and - were considered resistant to SFN, having MICs ≥ 16 - 32 μg/mL. These findings suggest that, with the dual action of SFN against a select group of microorganisms and its ability to inhibit tumor growth, SFN (or the consumption of SFN-containing vegetables) might be especially helpful in preventing certain types of infections in both cancer and non-cancer patients.[...]© Georg Thieme Verlag KG Stuttgart · New YorkGet connected:Table of contents | Abstract | Full text (Source: Planta Medica)

Chemotaxonomic study of medicinal taxus species with fingerprint and multivariate analysis

Planta Medica — Sat, 17 May 2008 15:54:18 +0100

Planta MedDOI: 10.1055/s-2008-1074531AbstractSpecies delimitation in has been controversial and it is very difficult to distinguish yew materials by their morphological characters. In this paper, a valid HPLC fingerprinting method coupled with multivariate analysis was used to define a framework for species identification and classification. Fingerprint-based similarity was employed for a chemotaxonomic study by hierarchical clustering analysis (HCA) and principal component analysis (PCA). Based on the PCA loadings, twelve chemical constituents were selected as chemotaxonomic markers which can be used to establish a more practical classification. Finally, eight studied species could be divided into six well-supported groups and most samples can be assigned to the correct species. Additionally, twelve markers were tentatively identified by LC/MS.[...]© Georg Thieme Verlag KG Stuttgart · New YorkGet connected:Table of contents | Abstract | Full text (Source: Planta Medica)

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Zaleplon: hallucinations and illusions: case report.