Protective Effect of Tetrahydroxystilbene Glucoside on 6-OHDA-Induced Apoptosis in PC12 Cells through the ROS-NO Pathway

Oxidative stress plays an important role in the pathogenesis of neurodegenerative diseases, such as Parkinson's disease. The molecule, 2,3,5,4′-tetrahydr- oxystilbene-2-O-β-D-glucoside (TSG), is a potent antioxidant derived from the Chinese herb, Polygonum multiflorum Thunb. In this study, we investigated the protective effect of TSG against 6-hydroxydopamine-induced apoptosis in rat adrenal pheochromocytoma PC12 cells and the possible mechanisms. Our data demonstrated that TSG significantly reversed the 6-hydroxydopamine-induced decrease in cell viability, prevented 6-hydroxydopamine-induced changes in condensed nuclei and decreased the percentage of apoptotic cells in a dose-dependent manner. In addition, TSG slowed the accumulation of intracellular reactive oxygen species and nitric oxide, counteracted the overexpression of inducible nitric oxide syntheses as well as neuronal nitric oxide syntheses, and also reduced the level of protein-bound 3-nitrotyrosine. These results demonstrate that the protective effects of TSG on rat adrenal pheochromocytoma PC12 cells are mediated, at least in part, by the ROS-NO pathway. Our results indicate that TSG may be effective in providing protection against neurodegenerative diseases associated with oxidative stress

Palladium catalyzed cross-coupling reactions of difunctional derivatives Bu

The Pd catalyzed organometallic coupling reactions of difunctional derivatives Bu3SnArBr has been used to prepare regioregular poly(3-alkylthiophenes) and poly(4-alkyl 2,2'-bithiophenes) with high molecualr weight

Synthèse de polymères conjugués par voie organométallique

Deux approches basées sur la chimie organométallique permettant de contrôler la régularité des enchaînements en série thiophénique sont analysés : (i) le couplage organométallique catalysé par un complexe de Pd○ d'un dérivé de l'étain et d'un halogénure aromatique.

GRF et sécrétion nocturne de GH chez l'enfant

International audienc

Herbicidal derivatives of aminomethylenebisphosphonic acid. Part III. Structure-activity relationship.

Derivatives of aminomethylenebisphosphonic acids constitute a class of promising herbicides. More than 40 N-substituted aminomethylenephosphonic acids were synthesized and evaluated for their herbicidal activity on common cress (Lepidium sativum L.) and cucumber (Cucumis sativus L.). Some of the tested compounds were found to exhibit strong herbicidal properties being equal in activity with the popular herbicide glyphosate as well as parent N-pyridylaminomethylenephosphonic acids. N-Substituted iminodi(methylenephosphonic) acids, which may be considered as close analog of glyphosate, were inactive toward test plants