Association of astragaloside IV-inhibited autophagy and mineralization in vascular smooth muscle cells with lncRNA H19 and DUSP5-mediated ERK signaling

Abstract

Defective autophagy in vascular smooth muscle cells (VSMCs) is the principal cause of atherosclerosis. This study aimed to investigate the effect of astragaloside IV (AS-IV) on VSMCs autophagy. In vivo, ApoE^−/− mice were fed with high-fat diet ad libitum for eight weeks, with or without AS-IV (25 mg/kg, daily). In vitro, human VSMCs were cultured and treated with β-Glycerophosphate (10 mmol/L) and AS-IV (50 μg/ml). VSMCs autophagy, mineralization, expression of p-ERK1/2, p-mTOR, and autophagy-related proteins (LC3 II/I, p62, and Beclin 1) were detected. Increased autophagy and mineralization was observed in VSMCs in thoracic aorta of mice and in in vitro VSMCs model of atherosclerosis. AS-IV administration attenuated the autophagy and mineralization in VSMCs. Reverse expression profiles of H19 and DUSP5 were observed. AS-IV inhibited DUSP5 and autophagy-related proteins and increased expression of H19, level of p-ERK1/2 and p-mTOR. Further, autophagy and mineralization level in VSMCs were in line with DUSP5 expression level, but in contrast to H19, p-ERK1/2, and p-mTOR profiles. We demonstrated that AS-IV could attenuate autophagy and mineralization of VSMCs in atherosclerosis, which may be associated with H19 overexpression and DUSP5 inhibition.