RESUMO
Aim To explore the effect of astragaloside IV (AS-IV) on cell proliferation and collagen expression in cardiac fibroblasts (CFs) of rats induced with angiotensin II (Ang II) and its mechanism. Methods CFs were pretreated with short-chain acyl-CoA dehydrogenase (SCAD) siRNA1186 for 12 h and then co-treated with Ang TJ and AS-IV for 36 h. The expressions of SCAD, α-SMA, collagen I and collagen III in CFs were detected by Western blot. mRNA expression levels of SCAD, a-SMA, collagen I and collagen III in CFs were detected by quantitative real-time PCR. The SCAD enzymatic activity, the content of ATP, hydroxyproline and free fatty acid were measured by detection kits. Results The expression of α-SMA, collagen I and collagen III were up-regulated (all P < 0. 01) in CFs induced by Ang II compared with the control cells, and the expression and enzymatic activity of SCAD significantly decreased (P < 0. 01, P< 0. 05). The content of ATP decreased (P < 0.01), and the content of hydroxyproline and free fatty acids increased (all P < 0.01). Compared with Ang II group, SCAD expression and enzymatic activity, and ATP content were significantly increased (all P < 0.01) in Ang II + AS-TV group, but the content of hydroxyproline and free fatty acids, and the expression of α-SMA, collagen I and collagen III significantly decreased (all P < 0.01). However, compared with the Ang II + NC group, there was no significant difference in all indices in the Ang II + SiRNA1186 + AS-TV group. The protective effect of AS-TV on Ang II -induced cell proliferation and collagen expression in CFs was eliminated by the interference of SCAD SiRNA1186. Conclusions AS-IV may inhibit Ang II-induced cell proliferation and collagen expression in CFs by activating SCAD.