Epicatechin and its in vivo metabolite, 3′-O-methyl epicatechin, protect human fibroblasts from oxidative-stress-induced cell death involving caspase-3 activation
- 15 March 2001
- journal article
- Published by Portland Press Ltd. in Biochemical Journal
- Vol. 354 (3), 493-500
- https://doi.org/10.1042/0264-6021:3540493
Abstract
There is considerable current interest in the cytoprotective effects of natural antioxidants against oxidative stress. In particular, epicatechin, a major member of the flavanol family of polyphenols with powerful antioxidant properties in vitro, has been investigated to determine its ability to attenuate oxidative-stress-induced cell damage and to understand the mechanism of its protective action. We have induced oxidative stress in cultured human fibroblasts using hydrogen peroxide and examined the cellular responses in the form of mitochondrial function, cell-membrane damage, annexin-V binding and caspase-3 activation. Since one of the major metabolites of epicatechin in vivo is 3′-O-methyl epicatechin, we have compared its protective effects with that of epicatechin. The results provide the first evidence that 3′-O-methyl epicatechin inhibits cell death induced by hydrogen peroxide and that the mechanism involves suppression of caspase-3 activity as a marker for apoptosis. Furthermore, the protection elicited by 3′-O-methyl epicatechin is not significantly different from that of epicatechin, suggesting that hydrogen-donating antioxidant activity is not the primary mechanism of protection.Keywords
This publication has 39 references indexed in Scilit:
- Epicatechin and Catechin are O-Methylated and Glucuronidated in the Small IntestineBiochemical and Biophysical Research Communications, 2000
- Apoptosis or senescence-like growth arrest: influence of cell-cycle position, p53, p21 and bax in H2O2 response of normal human fibroblastsBiochemical Journal, 2000
- Structure–activity relationships of quercetin in antagonizing hydrogen peroxide-induced calcium dysregulation in PC12 cells11Mention of a trade name, proprietary product or specific equipment does not constitute a guarantee by the United States Department of Agriculture and does not imply its approval to the exclusion of other products that may be suitable.Free Radical Biology & Medicine, 1999
- Polymethoxylated Flavones Derived from Citrus Suppress Tumor Necrosis Factor-α Expression by Human MonocytesJournal of Natural Products, 1999
- Suppression of nitric oxide synthase and the down‐regulation of the activation of NFκB in macrophages by resveratrolBritish Journal of Pharmacology, 1999
- Hydrogen Peroxide-Induced Apoptosis and Necrosis in Human Lung Fibroblasts: Protective Roles of GlutathioneThe Japanese Journal of Pharmacology, 1999
- Deglycosylation of flavonoid and isoflavonoid glycosides by human small intestine and liver β‐glucosidase activityFEBS Letters, 1998
- Mass Spectrometry of Selected Components of Biological Interest in Green Tea ExtractsJournal of Natural Products, 1998
- Structure-antioxidant activity relationships of flavonoids and phenolic acidsFree Radical Biology & Medicine, 1996
- Early redistribution of plasma membrane phosphatidylserine is a general feature of apoptosis regardless of the initiating stimulus: inhibition by overexpression of Bcl-2 and Abl.The Journal of Experimental Medicine, 1995