Effects of quercetin on mitochondrial energy metabolism function after myocardial ischemia
OBJECTIVE To investigate the effects of quercetin on mitochondrial energy metabolism function after myocardial ischemia.METHODS H9c2 cells were divided into blank group,model group,quercetin high-dose,medium-dose and low-dose groups(40,20,10 μmol/L),and positive control group(cyclosporine A,1 μmol/L).Reactive oxygen species(ROS),mitochondrial membrane potential(MMP),openness of mitochondrial permeability transition pore(MPTP),adenosine triphosphate(ATP),malondialdehyde(MDA),lactate dehydrogenase(LDH)and creatine kinase(CK)were observed after cell hypoxia treatment.Rats were randomly assigned into sham operation group,model group,quercetin high-dose,medium-dose and low-dose groups(100,50,25 mg/kg),and positive control group(trimetazidine,6.3 mg/kg),with 8 rats in each group.They were given relevant medicine intragastrically,once a day,for 7 consecutive days.After the last medication,myocardial ischemia model was induced by the ligation of the left anterior descending branch of the coronary artery.The contents of LDH,MDA,creatine kinase isoenzyme-MB(CK-MB),superoxide dismutase(SOD),complex Ⅰ,complex Ⅳ and ATP in serum were all determined.RESULTS Compared with the model group,ROS fluorescence intensity,openness of MPTP,the contents of CK,LDH and MDA were significantly decreased in quercetin low-dose,medium-dose and high-dose groups,and positive control group,while the contents of MMP and ATP were all increased significantly(P<0.01);the contents of CK-MB,LDH and MDA in serum were all decreased significantly in quercetin low-dose,medium-dose and high-dose groups,and positive control group,while the contents of SOD,complex Ⅰ,complex Ⅳ and ATP(except for positive control group)were increased significantly(P<0.05 or P<0.01).CONCLUSIONS Quercetin can effectively reduce myocardial hypoxic injury,promote endogenous energy production and improve mitochondrial function after myocardial ischemia.