The Protective Effects Of Alpha-lipoic On H9c2 Cardiomyocytes Undergoing Hypoxia Or Hypoxia/ Reoxygenationinjury And Its Possible Mechanism

Background Coronary heart disease(CHD) is one of the diseases threatening human life and health.The incidence of CHD is gradually rising with the improvement of living standards and the aging of the population increase.CHD is mainly caused by coronary artery occlusion or stenosis, insufficient blood supply and myocardial ischemia hypoxia or necrosis.The therapy of PCI and CABGare often considered in CHD patients caused by coronary artery occlusion or stenosis. Butthese therapyalso can inducemyocardial ischemia-reperfusion injury conversely. The drug treatment is still consideredwhen the coronary artery lesions did not meet the PCI treatment pointer or coronary vascular lesions is too serious to CABG.Therefore, the treatment of myocardial ischemia injury, and the same to myocardial ischemia-reperfusion injury is still a real problem, and how to further reduce the myocardial ischemia and ischemia-reperfusion injury is a hot topic in clinical.Objective To investigate the protective effects of alpha-lipoic(α-LA) on H9c2 cardiomyocytes undergoing hypoxia or hypoxia/reoxygenation(H/R) injury and explore its possible mechanisms.Methods H9c2 cardiomyocytes in hypoxia or H/R injury researches were respectively divided into normal control group, hypoxia or H/R group, hypoxia or H/R + α-LA group(LA group), hypoxia or H/R + α-LA + Daidzin group(Daidzin group) and hypoxia or H/R + α-LA +DMSO group(DMSO group). The myocardial cell survival rate was detected by MTT;the activity of LDH and ALDH2 were respectively analyzed by microtitration and ELISA; the MDA level was measured by TBA.Results(1) Compared to the normal control group, the cell survival rates of hypoxia and H/R group were decreased(P<0.01), the levels of MDA and LDH were significantly increased(P<0.01).(2) Compared to the hypoxia or H/R group, the cell survival rates and ALDH2 activities of LA group were improved(P<0.05), the levels of MDA and LDH were decreased(P<0.01).(3) Compared to the LA group and DMSO group, the cell survival rates and ALDH2 activities of Daidzin group were decreased(P<0.05), the levels of MDA and LDH were increased(P<0.05), and no significant differences of all the above measures were found between LA group and DMSO group(P>0.05).Conclusionα-LA can protect H9c2 cardiomyocytes from hypoxia or H/R injury by means of upregulating activities of ALDH2 and decreasing hypoxia or H/R induced lipid peroxidation.