Volume 29, Issue 3
DOI: 10.24205/03276716.2020.950
Effect of electroacupuncture "Shenmen"HT7 on the expression of ferroptosis related proteins GPX4, FTH1, TfR1 and ACSL4 in Acute Myocardial Ischemia Model Rats
Abstract
Objective: To observe the effect of electroacupuncture at the "Shenmen"(HT7) acupoint of the Heart Meridian on the related proteins of "ferroptosis" in the myocardium of (AMI) rats with myocardial ischemia.
Methods: Thirty-six healthy adult SD rats, weighing (230g ±20g), were randomly divided into three groups: sham operation group (Sham), model group (Model) and electroacupuncture group (EA), to establish acute myocardial ischemia rat (AMI). The rat model of acute myocardial ischemia was established by ligating the left anterior descending branch of coronary artery. The rats in the sham operation group were fed normally for 7 days after modeling, and the rats in the electroacupuncture group were stimulated by electroacupuncture for 7 days with a stimulation current of 1mA and a frequency of 2 Hz for 30min. In the sham operation group, the rats in the model group were fed normally for 7 days after modeling. The electrocardiogram of rats in each group was recorded and analyzed by PowerLab 16-lead physiological recorder. 7 days later, 6 rats in each group were taken from the left ventricle and killed. The ultrastructure of the apical tissue was observed under transmission electron microscope, the pathological changes of myocardial tissue were observed by HE staining, and the activities of Fe2 and glutathione (GSH) in myocardial tissue were determined by colorimetry. The mRNA expression levels of glutathione peroxidase 4 (GPX4), ferritin heavy chain polypeptide 1 (FTH1), transferrin receptor 1 (TfR1) and long chain acyl-CoA synthase 4 (ACSL4) in rat myocardium were detected by real-time fluorescence quantitative PCR (QT-PCR). The expressions of GPX4, FTH1, TFR1 and ACSL4 in rat myocardium were detected by Western blot.
Results: Compared with the sham operation group, the electrocardiogram ST segment of the model group was obviously elevated, the arrangement of cells in myocardial tissue was disordered, the myocardial fiber was broken, the interstitial hemorrhage was obvious, the mitochondrial atrophy became smaller, the membrane density increased, the myocardial Fe2 content increased and the GSH activity decreased, and the expression levels of GPX4, FTH1 mRNA and protein in myocardial tissue decreased (P < 0.01). The expression level of TFR1 and ACSL4 and the expression of protein were increased (P < 0.01). Compared with the model group, the ST segment decreased significantly, the arrangement of cardiomyocytes, the breakage of myocardial fibers, the interstitial hemorrhage decreased (P < 0.01), the mitochondrial atrophy decreased, the membrane density increased, the content of Fe2 decreased and the activity of GSH increased in the electroacupuncture group. The expression level of GPX4, FTH1 mRNA and protein in myocardial tissue increased (P < 0.01), while the expression level of TFR1 and ACSL4 and the expression of protein decreased in the electroacupuncture group.
Conclusion: The protective effect of acupuncture on the myocardium of AMI rats may be related to the inhibition of "ferroptosis" by affecting the expression of myocardial related proteins GPX4, FTH1, TfR1 and ACSL4.
Keywords
Electroacupuncture; HT7; AMI; Mechanism Ferroptosis