Effects of Baicalein on Rat Myocardial Ischemia and Neonatal Cardiomyocyte Injury

AimTo investigate the effects and mechanisms of baicalein on myocardial ischemic injury in rats caused by coronary artery ligation, and on H2O2-induced oxidation lesion or Na2S2O4-induced hypoxia/reoxygenation(H/R) injury of neonaltal cardiomyocytes.MethodsRats were pretreated with intragastric administration of baicalein for 7 days. After the last administration, animals received the ligation of the left coronary artery (LCA). Electrocardiogram was recorded during the whole ischemic procedure. 6 h after LCA, rats were killed and myocardial infarction ratio was measured by TTC staining. MDA content and SOD, CK and LDH activity in serum were spectrophotometrically determined. In vitro study, neonatal cardiomyocytes were pretreated with baicalein for 3 days before exposure to H2O2 or Na2S2O4. Viability of cardiomyocytes was assayed through the MTT method. LDH activity in media was also determined.ResultsCompared with the sham group, myocardial infarction ratio, serum CK and LDH activity and MDA content were obviously increased after LCA, while serum SOD activity was decreased. Pretreatment with baicalein effectively inhibited ischemia induced elevation of J point in ECG, and diminished CK, LDH and MDA in serum, and also decreased serum SOD activity in a dose-dependent manner. In vitro, pretreatment with baicalein increased the viability of H2O2-injured cardiomyocytes; and decreased the leakage of LDH. With regard to H/R-induced myocardial injury, the cardioprotective effects of baicalein were affected by the absence or presence of the drug during hypoxia.ConclusionThe results demonstrated baicalein had the ability to protect cardiomyoctyes from ischemic and oxidative injury in vivo and in vitro, which may be related to the capacity of baicalein on scavenging H2O2 and oxygen free radicals directly.