Abstract
The aim of the present study was to investigate the effects of Shenfu Qiangxin Drink (SFQXD) on acute myocardial infarction (AMI) and identify the possible underlying mechanisms. Levels of reactive oxygen species (ROS) and inflammatory factors, including interleukin (IL)-6, IL-1β and tumor necrosis factor-α (TNF-α) in the blood samples of patients with AMI were measured using commercially available kits by visible spectrophotometry after SFQXD administration. The contents of phosphorylated (p-) forkhead box O3a (FOXO3a) was examined using an ELISA kit. In addition, a hydrogen peroxide (H2O2)-induced myocardial injury model was established in vitro using neonatal rat cardiomyocytes. Following treatment with SFQXD, the levels of intracellular ROS, cell apoptosis, oxidative stress- and inflammation-related markers were measured using commercially available kits by visible spectrophotometry. Additionally, western blot analysis was used to measure the expression of sirtuin-4 (SIRT4), p-FOXO3a, acetylated FOXO3a (ace-FOXO3a) and apoptosis-related genes (Bcl-2, Bax, BIM and cleaved caspase-3). Subsequently, to investigate the possible underlying regulatory mechanisms, SIRT4 expression was silenced by transfection with small hairpin RNA against SIRT4, following which changes in the extent of oxidative stress, inflammation and apoptosis were assessed. The levels of ROS and interleukin (IL)-1β were found to be significantly reduced, whilst FOXO3a phosphorylation was markedly increased following administration with SFQXD. In vitro, SFQXD dose-dependently inhibited H2O2-induced oxidative stress, inflammation and apoptosis in neonatal rat cardiomyocytes. In addition, FOXO3a phosphorylation was markedly upregulated whilst FOXO3a acetylation was downregulated following treatment of H2O2-induced primary neonatal cardiomyocytes with SFQXD. SIRT4 knockdown also markedly reversed the effects of SFQXD on oxidative stress, inflammation and apoptosis in neonatal rat cardiomyocytes. In conclusion, these findings demonstrated that SFQXD may alleviate oxidative stress-induced myocardial injury by potentially regulating SIRT4/FOXO3a signaling, suggesting that SFQXD may be of clinical value for the treatment of AMI.