Network pharmacology and subsequent experimental validation reveal the synergistic myocardial protection mechanism of Salvia miltiorrhiza Bge. and Carthamus tinctorius L.

Objective: To reveal the molecular mechanism underlying the compatibility of Salvia miltiorrhiza Bge (S. miltiorrhiza, Dan Shen) and C. tinctorius L. (C. tinctorius, Hong Hua) as an herb pair through network pharmacology and subsequent experimental validation. Methods: Network pharmacology was applied to construct an active ingredient-efficacy target-disease protein network to reveal the unique regulation pattern of S. miltiorrhiza and C. tinctorius as herb pair. Molecular docking was used to verify the binding of the components of these herbs and their potential targets. An H9c2 glucose hypoxia model was used to evaluate the efficacy of the components and their synergistic effects, which were evaluated using the combination index. Western blot was performed to detect the protein expression of these targets. Results: Network pharmacology analysis revealed 5 pathways and 8 core targets of S. miltiorrhiza and C. tinctorius in myocardial protection. Five of the core targets were enriched in the hypoxia-inducible factor-1 (HIF-1) signaling pathway. S. miltiorrhiza-C. tinctorius achieved vascular tone mainly by regulating the target genes of the HIF-1 pathway. As an upstream gene of the HIF-1 pathway, STAT3 can be activated by the active ingredients cryptotanshinone (Ctan), salvianolic acid B (Sal. B), and myricetin (Myric). Cell experiments revealed that Myric, Sal. B, and Ctan also exhibited synergistic myocardial protective activity. Molecular docking verified the strong binding of Myric, Sal. B, and Ctan to STAT3. Western blot further showed that the active ingredients synergistically upregulated the protein expression of STAT3. Conclusion: The pharmacodynamic transmission analysis revealed that the active ingredients of S. miltiorrhiza and C. tinctorius can synergistically resist ischemia through various targets and pathways. This study provides a methodological reference for interpreting traditional Chinese medicine compatibility.