Effects of Kangdaxin on myocardial fibrosis in heart failure with preserved ejection fraction rats

BACKGROUND: This study aimed to explore the effects of Kangdaxin oral liquid on myocardial fibrosis in heart failure with preserved ejection fraction (HFpEF) rats. METHODS: A total of 30 Sprague Dawley (SD) rats were randomly divided into 3 groups Sham operation group (Sham), HFpEF group (HFpEF), and HFpEF with drug intervention group (HFpEF + I). Rats in HFpEF + I group were given Kangdaxin oral liquid at a dose of 2.7 mL/(kg·d). After modeling or treatment, the value of E/A and E/e' in each group of rats were measured by echocardiography. The N-terminal pro b-type natriuretic peptide (NT-proBNP) level was determined by enzyme-linked immunosorbent assay (ELISA). Heart weight/body mass index (Hw/W) and left ventricular weight/body mass index (LVw/W) were calculated after the rats were sacrificed; the transforming growth factor-β1 (TGF-β1) protein expression level in cardiac tissue was detected by western blot. RESULTS: Compared with sham group, the values of diastolic function item (E/A) and mitral annular early diastolic velocity (E/e') in HFpEF group were significantly decreased, and the level of NT-proBNP was significantly increased (P<0.05). Compared with HFpEF group, the value of E/A and E/e' in HF + I group were significantly increased, and the level of NT-proBNP was significantly decreased (P<0.05). Compared with sham group, the expression of TGF-β1 protein in heart tissue of HFpEF group were significantly increased (P<0.05). Compared with HFpEF group, the expression of TGF-β1 protein in HFpEF + I group were significantly decreased (P<0.05). CONCLUSIONS: Kangdaxin oral liquid has protective effect on heart in HFpEF rats, which can reduce the protein expression of TGF-β1 in the heart tissue of HFpEF rats. This may be a possible mechanism to inhibit myocardial fibrosis and improve cardiac diastolic function.