Network Pharmacology & Validation of Dihydrotanshinone I's Regulation of HIF-1α via STAT3 in Cardiomyocytes.

This study investigates the molecular mechanisms underlying the cardioprotective effects of dihydrotanshinone I (DT). Bioinformatics analysis of proteomic data was applied to explore the broad regulatory effects of DT on cellular processes in cardiomyocytes. Molecular docking and surface plasmon resonance (SPR) analysis were performed to identify potential targets of DT. Bioinformatics analysis identified key pathways influenced by DT, suggesting its potential for modulating cellular processes involved in stress responses. Molecular docking analysis predicted signal transducer and activator of transcription 3 (STAT3) as a high-affinity target of DT, which was confirmed by SPR and thermal stability assays. DT treatment enhanced STAT3 phosphorylation and promoted both transcriptional upregulation and nuclear accumulation of hypoxia-inducible factor-1α (HIF-1α) in cardiomyocytes. These effects were abolished by STAT3 inhibition. Single-cell ribonucleic acid sequencing of human heart tissues demonstrated similar expression patterns of STAT3 and hypoxia inducible factor 1 subunit alpha across cardiac cell types, particularly in cardiomyocytes. Analysis of ischemic cardiomyopathy patients revealed significantly downregulated expressions of both genes compared to normal hearts, supporting their relevance in cardiac pathology. These findings suggest that DT confers cardioprotection through modulation of the STAT3/HIF-1α axis, potentially mimicking or enhancing ischemic preconditioning effects. In summary, this study provides new insights into the cardioprotective mechanisms of DT and highlights the STAT3/HIF-1α pathway as a promising target for ischemia/reperfusion injury.