Protective Effects of Tianxiangdan Capsule Drug-Containing Plasma Against H2O2-Induced Oxidative Stress in Primary Cardiomyocytes
Abstract Background: Tianxiangdan capsule (TXD), developed in our hospital, has been clinically used in the treatment of coronary heart disease angina pectoris. This study aimed at evaluating the mechanisms of TXD against myocardial ischemia and to provide evidence for its subsequent clinical application. METHODS: Active components and mechanisms of action of TXD against myocardial ischemia were predicted and analyzed by network pharmacology and molecular docking. The oxidative damage model was established using H2O2, which caused myocardial cell damage. The MTT assay was used to evaluate cell viability, Hoechst33342 staining, while cleaved caspase-3 immunofluorescence staining was used to determine cell apoptosis. Fluorescent probe method detected ROS and intracellular Ca2+, while spectrophotometry was used to measure SOD, MDA, and NO levels in myocardial cells. Western blotting was used to detect the expression levels of ESR1, PI3K, AKT, and eNOS in cells. RESULTS: It was found that TXD plays a protective role in myocardial ischemia through the estrogen pathway, and its main active components were isoflavones. The TXD drug-containing plasma exhibited increased cell survival rates and suppressed MDA levels, elevated SOD and NO levels, and significantly suppressed ROS levels as well as intracellular Ca2+ levels. Moreover, the TXD drug-containing plasma pretreated cells had significantly suppressed PI3K and AKT expression levels, as well as elevated ESR1 and eNOS expression levels. Conclusion: TXD may exhibit estrogen-like effects, through the estrogen pathway enhances cardiomyocytes' antioxidant capacities, and improves oxidative stress injury as well as cell apoptosis.