Astragaloside IV alleviates heart failure by regulating SUMO-specific protease 1

Abstract

The present study investigated whether the protective effect and mechanism of astragaloside IV (AS-IV) on heart failure (HF) involves small ubiquitin-like modifier (SUMO)-specific protease 1 (Senp1). Mouse HF was established by aortic constriction, inducing pressure overload. The model was confirmed by echocardiography 6 weeks after surgery. Mice were randomly divided into control, HF, HF+AS-IV, and AS-IV groups. Ventricular function was examined by echocardiography. Morphological changes of myocardial tissues were examined by H&E staining. The protein levels of the apoptosis-related proteins, cleaved caspase-3, caspase-3, Bcl2, Bax, and SUMO-Senp1 were determined by Western blotting. H₂O₂ in isolated mitochondria and cells was determined by Amplex Red. A reactive oxygen species (ROS) detection kit determined ROS levels in isolated mitochondria and HL-1 cells. JC-1 reagent measured mitochondrial membrane potential (ΔΨm). Apoptosis of HL-1 cells was examined by terminal deoxynucleotidyl transferase dUTP nick end labeling. Compared with the control group, the heart weight and heart mass/body weight ratio increased in the HF group (P<0.05). Furthermore, the ejection fraction and left ventricular shortening fraction decreased (P<0.05), while the left ventricular end-diastolic diameter (LVID;d) and end-systolic diameter (LVID;s) increased (P<0.05). Finally, mitochondrial ROS and H₂O₂ increased (P<0.05), while the ΔΨm decreased (P<0.05). However, AS-IV improved the cardiac function of HF mice, decreased the level of ROS and H₂O₂ in the myocardium, suppressed the decrease in ΔΨm, and decreased the apoptosis of myocardial cells (P<0.05). AS-IV also decreased the Senp1-overexpression. Furthermore, in HL-1 cells, Senp1-overexpression significantly inhibited the protective effects of AS-IV. AS-IV decreased oxidative stress in cardiomyocytes, decreased mitochondrial damage, inhibited ventricular remodeling, and ultimately improved cardiac function by inhibiting HF-induced Senp1-overexpression. This mechanism provides a novel theoretical basis and clinical treatment for HF.

Keywords: SUMO protease 1; astragaloside IV; heart failure; mitochondrial membrane potential; oxidative stress.