Effect of Yixintai on Mitochondrial Fission Proteins Fis1 and Mff in Rat Model of Chronic Heart Failure / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo study the effect and mechanism of Yixintai on mitochondrial fission proteins in the rat model of chronic heart failure. MethodTen of 60 SD rats were randomly selected as the sham operation group， and the remaining 50 rats were subjected to ligation of the left anterior descending coronary artery for the modeling of heart failure post myocardial infarction. The successfully modeled rats were randomized into model， low-， medium-， and high-dose （1.4， 2.8， and 5.6 g·kg-1， respectively） Yixintai， and trimetazidine （10 mg·kg-1） groups. The rats were administrated with corresponding doses of drugs by gavage， and the rats in the model group and sham operation group were given an equal volume of normal saline by gavage for 28 consecutive days. Enzyme-linked immunosorbent assay （ELISA） was then employed to measure the levels of amino-terminal pro-B-type natriuretic peptide （NT-pro BNP）， B-type natriuretic peptide （BNP）， and adenosine triphosphate （ATP） in the serum. Color Doppler ultrasound imaging was conducted to examine the cardiac function indicators. Hematoxylin-eosin staining and Masson staining were conducted to observe the pathological changes in the heart， and Image J was used to calculate collagen volume fraction （CVF）. Transmission electron microscopy was employed to observe the ultrastructural changes of myocardial cells. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling （TUNEL） was employed to measure the apoptosis rate of myocardial cells. Western blot was employed to determine the protein levels of mitochondrial fission protein 1 （Fis1） and mitochondrial fission factor （Mff） in the outer mitochondrial membrane of the myocardial tissue. ResultCompared with the sham operation group， the model group showed elevated levels of NT-pro BNP and BNP in the serum， decreased ATP content， left ventricular ejection fraction （LVEF）， and left ventricular fraction shortening （LVFS）， increased left ventricular end-diastolic diameter （LVIDd） and left ventricular end-systolic diameter （LVIDs）， disarrangement of myocardial cells， inflammatory cell infiltration， increased collagen fibers and CVF， damaged myocardium and mitochondria， and increased apoptosis rate of myocardial cells， and up-regulated expression of Fis1 and Mff in the cardiac tissue （P<0.01）. Compared with the model group， different doses of Yixintai and trimetazidine lowered the serum levels of NT-pro BNP and BNP （P<0.05）， increased the ATP content （P<0.05）， increased LVEF and LVFS （P<0.01）， decreased LVIDd and LVIDs （P<0.01）. Moreover， the drugs alleviated the myocardial inflammatory damage and fibrosis， reduced CVF （P<0.01）， repaired the myocardial mitochondrial structure， and decreased the apoptosis rate of myocardial cells （P<0.01）. Medium- and high-dose Yixintai and trimetazidine down-regulated the expression of Fis1 and Mff in the myocardial tissue （P<0.05）. ConclusionYixintai can improve mitochondrial structure， reduce myocardial cell apoptosis， and improve cardiac function by inhibiting the expression of Fis1 and Mff in the myocardial tissue.