Protective Effect of Xihuang Pill on Immune Checkpoint Inhibitors-Related Myocarditis in a Mouse Model by Regulating the HIF-1 Signaling Pathway.

[BACKGROUND] Immune checkpoint inhibitor (ICIs)-associated cardiotoxicity is a significant cause of immune-related adverse events and mortality in cancer immunotherapy, lacking effective preventative or therapeutic strategies. Xihuang Pill (XHW), a traditional Chinese medicine with established anti-inflammatory properties and clinical use in cancer treatment and adverse event mitigation, merits investigation for its efficacy against ICIs-induced cardiac toxicity.

[PURPOSE] To investigate XHW's therapeutic effects on Immune checkpoint inhibitors (ICIs)-associated cardiotoxicity and its underlying mechanisms.

[METHODS] This study utilized mass spectrometry technology to identify the chemical components in XHW. The experimental model for ICIs-associated myocarditis was generated in BALB/c mice by immunizing them with murine cardiac troponin I (cTnI) peptide and administering anti-programmed death 1 (PD-1) antibodies to mice. Mice received varying XHW dosages (0.39, 0.78, and 1.56 mg/kg). Myocardial contractility and plasma cardiac injury markers (CK, CK-MB) were assessed. Metabolomics and transcriptomics identified key signaling pathways modulated by XHW, validated via real-time quantitative PCR (QT-PCR). In addition, a correlation analysis was conducted between key genes and differential metabolites.

[RESULTS] Mass spectrometry identified 171 components in XHW. Pharmacological studies demonstrated that XHW improved cardiac contractility, reduced plasma cardiac injury biomarkers, and attenuated myocardial injury in the myocarditis model. Integrated metabolomic and transcriptomic analyses revealed that XHW primarily modulates the HIF-1 signaling pathway, significantly upregulating mRNA expression and downregulating the mRNA expression of , and . Correlation analysis identified significant associations between 16 metabolites, including 13-tetradecynoic acid, 1-pentadecanoylglycerol, and arginyl-glycyl-aspartic acid, and these genes.

[CONCLUSION] These findings suggest that XHW may alleviate ICIs-associated myocarditis via HIF-1 signaling pathway, offering a promising therapeutic approach for ICIs-related cardiotoxicity.