"标本配穴"电针预处理减轻心肌缺血再灌注损伤大鼠心肌细胞铜死亡的机制研究OA

Objective To observe the effect of"biaoben acupoint combination"electroacupuncture(EA)pretreatment on cardiomyocyte cuproptosis in rats with myocardial ischemia-reperfusion injury(MIRI),and to explore its underlying mechanism.Methods From 70 male Sprague-Dawley(SD)rats,10 rats were randomly selected as the sham operation(Sham)group,and the remaining rats were randomly divided into a model(MIRI)group,an elesclomol(ES)group,a"biaoben acupoint combination"EA pretreatment(EA)group,and a"biaoben acupoint combination"EA pretreatment+elesclomol(EA+ES)group,with 15 rats in each group.In the EA group and the EA+ES group,EA pretreatment was applied at bilateral"Neiguan"(PC6),bilateral"Zusanli"(ST36),and"Guanyuan"(CV4),with continuous wave,2 Hz in frequency,20 min each time,once daily for 7 consecutive days.On day 8,except for the Sham group,MIRI model was established by ligation of the left anterior descending branch in the remaining groups.Thirty minutes before modeling,in the ES group and the EA+ES group,intraperitoneal injection of the copper ionophore elesclomol(5 mg/kg)was delivered.After modeling,myocardial infarct area was measured by TTC staining;morphology of cardiomyocytes in the ischemic area was observed by HE staining;mitochondrial ultrastructure of cardiomyocytes in the ischemic area was observed by transmission electron microscopy;the expression of mitochondrial respiratory chain complexes of cardiomyocytes in the ischemic area was detected by ELISA;and the protein expression of ceruloplasmin(Cp),ferredoxin 1(FDX1),dihydrolipoamide S-succinyltransferase(DLST)and dihydrolipoamide S-acetyltransferase(DLAT)of cardiomyocytes in the ischemic area was detected by Western blot.Results Compared with the Sham group,the myocardial infarct area and the protein expression of Cp,FDX1,DLST and DLAT of cardiomyocytes in the ischemic area were increased(P＜0.01),while the expression of mitochondrial respiratory chain complexes Ⅰ-Ⅳ of cardiomyocytes in the ischemic area was decreased(P＜0.01)in the MIRI group.Compared with the MIRI group,the myocardial infarct area and the protein expression of Cp,FDX1,DLST and DLAT of cardiomyocytes in the ischemic area were decreased(P＜0.01),while the expression of mitochondrial respiratory chain complexes Ⅰ-Ⅳ of cardiomyocytes in the ischemic area was increased(P＜0.01)in the EA group;the protein expression of Cp and FDX1 of cardiomyocytes in the ischemic area was increased in the ES group(P＜0.01);the protein expression of Cp,FDX1,DLST and DLAT of cardiomyocytes in the ischemic area was decreased(P＜0.01),while the expression of mitochondrial respiratory chain complexes Ⅰ-Ⅳ of cardiomyocytes in the ischemic area was increased(P＜0.05)in the EA+ES group.Compared with the EA group,the myocardial infarct area and the protein expression of Cp,FDX1,DLST and DLAT were increased(P＜0.01,P＜0.05),while the expression of mitochondrial respiratory chain complexes Ⅰ-Ⅳ of cardiomyocytes in the ischemic area was decreased(P＜0.01)in the EA+ES group.Compared with the MIRI group and the ES group,in the EA group and the EA+ES group,disordered arrangement of myocardial mitochondria,mitochondria edema,and mitochondrial outer membrane rupture were improved,the improvement in the EA group was more pronounced.Conclusion"Biaoben acupoint combination"EA pretreatment can attenuate the structural damage of cardiomyocytes and mitochondria,enhance the expression of mitochondrial respiratory chain complexes Ⅰ-Ⅳ in MIRI rats,and alleviate MIRI by inhibiting elesclomol-induced cardiomyocyte cuproptosis.