Clarifying therapeutic mechanisms of guanxinshutong capsule for cardiac fibrosis treatment by network pharmacology, molecular docking, molecular dynamics simulation, and in vivo experiments

Purpose: Guanxinshutong capsule (GXST) is a Chinese patent medicine used for the treatment of cardiac fibrosis (CF). Nevertheless, the precise mechanism of action of GXST remains unclear. In this study, we applied network pharmacology, molecular docking, molecular dynamics simulation, and in vivo experiments to assess the effects and mechanisms of GXST in the treatment of CF. Methods: The TCMSP database provided the GXST targets and active substances. The GeneCards, OMIM, and TTD databases were searched for targets relevant to cardiac fibrosis. To filter core targets, a PPI network was set up. Metascape was utilized to conduct enrichment analysis for the KEGG and GO pathways. To evaluate the interaction between putative targets and active drugs, molecular docking was utilized. MDS was performed for the optimal complex of the core ligand protein identified through molecular docking. Induction of cardiac fibrosis in SD rats using isoproterenol, and the protective effects of GXST on the heart were evaluated using echocardiography, H&E staining, and Masson staining. Results: Through network pharmacology analysis, we have identified 83 active components and 73 key target proteins related to cardiac fibrosis from GXST. Subsequent molecular docking and molecular dynamics simulation results suggest that quercetin, luteolin, and kaempferol can inhibit cardiac fibrosis by regulating the expression of TNF-α, IL6, and IL1B proteins. These compounds and proteins may be key factors in the treatment of CF with GXST. Further, in vivo experiments demonstrate that GXST can alleviate myocardial injury and improve cardiac function in CF rats. Conclusion: This study successfully predicted the effective components, potential targets, and related pathways involved in treating CF by GXST. GXST can improve cardiac function and alleviate pathological damage in the hearts of SD rats. This provides a new strategy for future investigations into the mechanisms of GXST in the treatment of CF.