Protective effect of isorhamnetin on H9 C2 cell line against oxidative stress / 中国药理学通报

ABSTRACT

Aim To investigate the protective effect of isorhamnetin on H9 C2 myocardial cell line and its mechanisms. Methods The toxicity and optimal pro-tective concentration of isorhamnetin were determined by MTT assay. The experimental subjects were divided into four groups:group N ( normal ) , group M ( mod-el) , group M + ISO ( model + isorhamnetin ) , and group ISO ( isorhamnetin only ) . Group M +ISO and ISO were pre-incubated with isorhamnetin for 12 hours while other groups with plain DMEM. Group M and M+ ISO were treated with 300μmol · L-1 H2 O2 for 4 hours after pre-incubation. Mitochondrial membrane potential depolarization of H9 C2 was measured by fluo-rescence microscope. Apoptotic rate and ROS produc-tion of injured myocardial cell line were detected using flow cytometry. The oxidative indictors were measured by spectrophotometry. The expressions of cytoplasmic cytochrome C, caspase-9, caspase-3, Bcl-2, Bax, Nrf2 and HO-1 were examined by Western blot. Result There was no difference in mitochondrial membrane potential depolarization, apoptotic rate, ROS produc-tion, oxidative indictors production and expressions of cytoplasmic cytochrome C, caspase-9,caspase-3, Bcl-2 , Bax between groups ISO and N ( P>0. 05 ) . Apop-totic rate, ROS production, expressions of cytoplasmic cytochrome C, caspase-9, caspase-3, Bax, MDA pro-duction of group M+ISO were significantly lower than those of group M ( P Nuclear translocation of Nrf2 and expression of HO-1 in myocardial cell line were increased with the prolonged isorhamnetin incubation time. Conclusion Isorham-netin could protect myocardial cell line against H2 O2-induced oxidative injury and apoptosis through the in- terruption of mitochondrial dependent apoptotic path-way and activation of Nrf2/ARE pathway.