Evidence for the association of peroxidases with the antioxidant effect of p-coumaric acid in endothelial cells exposed to high glucose plus arachidonic acid.
Although many plant-derived phenolic compounds display antioxidant effects in biological systems, their mechanism of action remains controversial. In this study, the mechanism by which p-coumaric acid (p-CA) performs its antioxidant action was investigated in bovine aortic endothelial cells under oxidative stress due to high levels of glucose (HG) and arachidonic acid (AA), a free fatty acid. p-CA prevented lipid peroxidation and cell death due to HG+AA without affecting the production of reactive oxygen species. The antioxidant effect of p-CA was not decreased by buthionine-(S,R)-sulfoximine, an inhibitor of cellular GSH synthesis. In contrast, pretreatment with p-CA caused the induction of peroxidases that decomposed t-butyl hydroperoxide in a p-CA-dependent manner. Furthermore, the antioxidant effect of p-CA was significantly mitigated by methimazole, which was shown to inhibit the catalytic activity of 'p-CA peroxidases' in vitro. Therefore, it is suggested that the induction of these previously unidentified 'p-CA peroxidases' is responsible for the antioxidant effect of p-CA. [BMB reports 2009; 42(9): 561-567].
Lee
Seung Jin
SJ
Department of Molecular Medicine and Cell and Matrix Research Institute, BK21 Medical Education Program for Human Resources, Kyungpook National University School of Medicine, Daegu, Korea.
Mun
Gyeong In
GI
An
Sang Mi
SM
Boo
Yong Chool
YC
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D013956:Antithyroid Agents / Q000494:pharmacology; D016718:Arachidonic Acid / Q000494:pharmacology*; D002417:Cattle; D002478:Cells, Cultured; D003373:Coumaric Acids / Q000494:pharmacology*; D004338:Drug Combinations; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008713:Methimazole / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D010544:Peroxidases / Q000378:metabolism*; D011422:Propionates; D017382:Reactive Oxygen Species / Q000378:metabolism; D013549:Sweetening Agents / Q000494:pharmacology; D020122:tert-Butylhydroperoxide / Q000494:pharmacology
D000975:Antioxidants; D013956:Antithyroid Agents; D003373:Coumaric Acids; D004338:Drug Combinations; D011422:Propionates; D017382:Reactive Oxygen Species; D013549:Sweetening Agents; D016718:Arachidonic Acid; D008713:Methimazole; D020122:tert-Butylhydroperoxide; D010544:Peroxidases; D005978:Glutathione; C495469:p-coumaric acid; D005947:Glucose