Objective: To study the effect of organic acid from Fructus mume on oxidative stress injury induced by hypoxia/reoxygenation (H/R) in cardiomyocytes and its mechanism.Methods: Myocardial cells H9C2 were randomly divided into control group, H/R group, H/R+group of different concentrations of organic acid. Myocardial cell survival was detected by MTT assay. Superoxide dismutase(SOD) activity, catalase(CAT) activity, malondialdehyde(MDA) content, aspartate aminotransferase(AST) level, creatine kinase(CK) level and lactate dehydrogenase(LDH) level were determined by kit. Apoptosis of cardiomyocytes was detected by flow cytometry. The expressions of Bax, Bcl2 and Nrf2-ARE signaling pathway-related proteins Nrf2, HO-1 and NQO1 were analyzed by Western blotting. Results: Compared with the control group, H/R treatment significantly reduced myocardial cell survival rate, SOD activity, CAT activity, obviously improved MDA content, AST, CK and LDH levels, and increased apoptosis rate and Bax protein expression, as well as reduced the expression of Bcl2, Nrf2, HO-1, NQO1 protein, and the differences were all significant (P<0.05). Compared with H/R group, 1, 2 mg·ml-1organic acid from Fructus mumesignificantly increased the survival rate of H/R injured cardiomyocytes (P<0.05). Compared with H/R group, organic acid from Fructus mume significantly increased SOD activity and CAT activity of H/R injured cardiomyocytes, decreased MDA content, AST, CK and LDH levels, myocardial apoptosis rate and Bax protein expression, increased Bcl2, Nrf2, HO-1, NQO1 protein levels, and the differences were all significant (P<0.05).Conclusion: Organic acid from Fructus mume protects oxidative stress damage induced by H/R by activating Nrf2-ARE signaling pathway.
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