Bouhamidi R. Prevost V. Nouvelot A.
Laboratoire de neurosciences, UMR 6551 du CNRS, universite de Caen, France. Title
High protection by grape seed
proanthocyanidins (GSPC) of polyunsaturated fatty acids against UV-C induced peroxidation.
Comptes Rendus de l Academie des Sciences - Serie Iii, Sciences de la Vie. 321(1):31-8, 1998 Jan.
The antioxidative effects of grape seed proanthocyanidins (GSPC) were studied in three in-vitro models in which polyunsaturated fatty acids (PUFAs) in aqueous solution and mice liver or brain microsomes were used as oxidative substrates, and UV-C irradiation as the pro-oxidant system. Analysis of UV-C induced lipid peroxidation was carried out by two methods: gas liquid chromatography of residual PUFAs and release of thiobarbituric acid-reactive substances (TBARs) measured by TBA reaction. Results indicate that PUFAs are more radiosensitive when incorporated in single component micelles than in mixed component micelles or microsomes. In every case, PUFA peroxidation was inhibited by low concentrations of GSPC (2 mg/L) while epigallocatecin (EGC) and epigallocatechin gallate (EGCG) monomers, at an equivalent level of epicatechin, exhibited no efficacy in our experimental conditions. This latter effect might be explained by a synergistic action of flavan-3-ol monomers, dimers and oligomers contained in the grape seed extract.
Bagchi D. Garg A. Krohn RL. Bagchi M. Tran MX. Stohs SJ. Institution
School of Pharmacy, Creighton University, Omaha, NE 68178, USA. Title
Oxygen free radical scavenging abilities of vitamins C and E, and a grape seed proanthocyanidin extract in vitro.
Research Communications in Molecular Pathology & Pharmacology. 95(2):179-89, 1997 Feb.
Proanthocyanidins, a group of polyphenolic bioflavonoids, have been reported to exhibit a wide range of biological, pharmacological and chemoprotective properties against oxygen free radicals. We have assessed the concentration-dependent oxygen free radical scavenging abilities of a grape seed proanthocyanidin extract (GSPE), vitamin C and vitamin E succinate (VES) as well as superoxide dismutase, catalase and mannitol against biochemically generated superoxide anion and hydroxyl radical using a chemiluminescence assay and cytochrome c reduction. A concentration-dependent inhibition was demonstrated by GSPE. At a 100 mg/l concentration, GSPE exhibited 78-81% inhibition of superoxide anion and hydroxyl radical. Under similar conditions, vitamin C inhibited these two oxygen free radicals by approximately 12-19%, while VES inhibited the two radicals by 36-44%. The combination of superoxide dismutase and catalase inhibited superoxide anion by approximately 83%, while mannitol resulted in an 87% inhibition of hydroxyl radical. The results demonstrate that GSPE is a more potent scavenger of oxygen free radicals as compared to vitamin C and VES.