title: MAPK pathway mediates the protective effects of onychin on oxidative stress-induced apoptosis in ECV304 endothelial cells.
abstract: Our recent studies have shown that onychin could protect rabbit aortic rings from lysophosphatidylcholine-induced injury by preserving endothelium-dependent relaxation and alleviating acute endothelial damage mediated by oxidative stress. However, the effect of onychin on apoptosis of endothelial cells induced by oxidative stress was not evaluated. In the present study, we investigated the effect of onychin on Hydrogen Peroxide (H2O2) induced apoptosis of ECV304 endothelial cells. Cultured human umbilical vein endothelial cell line (ECV304) was pretreated with vehicle (DMSO), genistein, or different concentrations of onychin (0.1, 0.3, 1, 3, and 10 micromol/L) for 30 minutes and then exposed to 1 mmol/L H2O2 for 24 hours. Cell apoptosis was determined by TUNEL and flow cytometric analysis. Meanwhile, Western-blot was used to measure the expression of phospho-ERK1/2, phospho-p38 and caspase-3. Our data showed that onychin treatment exhibited a protective effect on ECV304 endothelial cells from H2O2-induced apoptosis in a concentration-dependent manner. Moreover, onychin attenuated H2O2-induced phosphorylation of p38MAPK and increased H2O2-induced phosphorylation of ERK1/2. Furthermore, onychin decreased the activation of caspase-3. The opposing effects of onychin on phosphorylation levels of p38MAPK and ERK1/2, and its caspase-3 inhibition might play a role in the beneficial effect of onychin on endothelial injury.
authors.affiliation: Institute of Pharmacy and Pharmacology, Nanhua University, Changsheng Road 28#, Hengyang 421001, Hunan, China.
authors.forename: Qin-Hui
authors.initials: QH
authors.lastname: Tuo
authors.forename: Chun
authors.initials: C
authors.lastname: Wang
authors.forename: Feng-Xiang
authors.initials: FX
authors.lastname: Yan
authors.forename: Duan-Fang
authors.initials: DF
authors.lastname: Liao
mesh_terms: D000470:Alkaloids / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D053148:Caspase 3; D020169:Caspases / Q000096:biosynthesis; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects* / Q000201:enzymology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000096:biosynthesis; D044950:Flavanones; D005434:Flow Cytometry; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D020287:In Situ Nick-End Labeling; D020935:MAP Kinase Signaling System / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D010766:Phosphorylation; D020011:Protective Agents / Q000494:pharmacology*; D011728:Pyridones; D048051:p38 Mitogen-Activated Protein Kinases / Q000096:biosynthesis / Q000378:metabolism*
chemical_list: D000470:Alkaloids; D044950:Flavanones; D020011:Protective Agents; D011728:Pyridones; C054955:onychine; D006861:Hydrogen Peroxide; D048049:Extracellular Signal-Regulated MAP Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases