Mechanism exploration of Salvia miltiorrhiza Bunge against trastuzumab induced cardiotoxicity via multi-omics.

[ETHNOPHARMACOLOGICAL RELEVANCE] Despite the initial efficacy of trastuzumab (TRZ) in breast cancer treatment, its use is hampered by cardiotoxicity. Salvia miltiorrhiza Bunge (DS) has demonstrated potential in treating cardiovascular diseases, but its role in mitigating TRZ-induced cardiotoxicity remains unclear.

[MATERIALS AND METHODS] We established both in vitro and in vivo models of TRZ-induced cardiotoxicity. Cell viability was measured using the CCK-8 assay following intervention with DS extract. The efficacy of varying doses of DS extract was assessed in the in vivo rat model. Cardiac function was determined via echocardiography, myocardial injury via biochemical markers, and tissue damage via hematoxylin and eosin (H&E) staining. Multi-omics integration (metabolomics, transcriptomics and network pharmacology) was used to identify potential therapeutic targets and bioactive compounds. We employed Western blot analysis and immunofluorescence to confirm that DS extract modulates ferroptosis-related proteins. We used transmission electron microscopy (TEM) to observe the mitochondrial morphology in rat myocardial tissue. Then we employed molecular docking and dynamics simulations to validate the binding affinities of compounds to their targets.

[RESULTS] DS was found to exert cytotoxic effects on JIMT-1 breast cancer cells, as well as significantly ameliorating TRZ-induced myocardial injury in H9c2 rat cardiomyocytes in a dose-dependent manner. DS extract significantly improved cardiac function and reduced markers of myocardial injury in TRZ treated rats, while also attenuating histopathological damage. A combined analysis of transcriptomics, metabolomics and network pharmacology identified potential bioactive compounds and targets. Further validation revealed that DS extract treatment increased the expression of GPX4 and decreased the expression of ACSL4, thereby inhibiting lipid peroxidation and oxidative stress. TEM observations revealed that DS extract alleviates mitochondrial damage induced by TRZ. Tanshinone I, tanshinone II A, and tanshinone II B demonstrated a strong binding affinity for ACSL4 and GPX4 in molecular docking and dynamic simulations.

[CONCLUSION] DS extract alleviates TRZ-induced cardiotoxicity, manifested by improved cardiac function, reduced myocardial injury markers, and mitigated tissue and mitochondrial damage. Its mechanism of action is associated with regulating proteins in the ferroptosis pathway (upregulating GPX4 and downregulating ACSL4). Additionally, tanshinone I, IIA, and IIB have been identified as potential active components.