From: Doug Skrecky (oberon@vcn.bc.ca)
Date: Sat Aug 21 1999 - 20:42:18 MDT
Citations: 1-2
<1>
Authors
Bouhamidi R. Prevost V. Nouvelot A.
Institution
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.
Source
Comptes Rendus de l Academie des Sciences - Serie Iii, Sciences de la Vie.
321(1):31-8, 1998 Jan.
Abstract
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.
<2>
Authors
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.
Source
Research Communications in Molecular Pathology & Pharmacology. 95(2):179-89,
1997 Feb.
Abstract
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.
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