RESUMEN
BACKGROUND: N6-adenosine methylation (m6A) is a prevalent RNA modification associated with heart failure, alongside aberrant miRNA expression. Despite indications of miRNAs regulating m6A modification, their specific influence on m6A in heart failure remains unclear. METHODS: The initial analysis utilized transcriptome and methylation sequencing data from GSE131296 in mice to identify key m6A methylation enzymes in heart failure and construct an associated network. Integration of miRNA sequencing data from GSE231700 revealed miRNAs influencing m6A methylation enzymes, contributing to the formation of a comprehensive network. Furthermore, differential miRNA levels in human serum were assessed via qPCR, and the expression of m6A methyltransferases in the heart was confirmed using proteomic databases. RESULTS: In pressure overload-induced heart failure mice, 217 mRNAs showed differential expression, with FTO and IGF2BP2 identified as m6A methylation enzymes. Subsequent methylation sequencing revealed 884 highly-methylated and 178 lowly-methylated peaks, establishing a network linking Fto and Igf2bp2 with these peaks. Additionally, miRNA sequencing identified 156 differentially expressed miRNAs, including let-7b-5p and miR-23b-3p, predicted as m6Aregulating miRNAs, both elevated in heart failure patients. CONCLUSION: miR-23b-3p and let-7b-5p are identified as potential regulators of RNA methylation in heart failure, acting via FTO and IGF2BP2, offering new insights into the role of miRNA-mediated RNA methylation and its potential therapeutic avenues for heart failure.
RESUMEN
Background: There are no specific clinical medications that target cardiac fibrosis in heart failure (HF). Recent studies have shown that tyrosine kinase inhibitors (TKIs) may benefit fibrosis in various organs. However, there is limited research on their application in cardiac fibrosis. Axitinib, an FDA-approved tyrosine kinase inhibitor, was used to evaluate its effects on cardiac fibrosis and function in pressure overload-induced heart failure. Methods: To build a pharmacological network, the pharmacological targets of axitinib were first retrieved from databases and coupled with key heart failure gene molecules for analysis and prediction. To validate the results outlined above, 8-week-old male C57BL/6 J mice were orally administrated of axitinib (30 mg/kg) daily for 8 weeks after Transverse Aortic Constriction (TAC) surgery. Mouse cardiomyocytes and cardiac fibroblasts were used as cell lines to test the function and mechanism of axitinib. Results: We found that the pharmacological targets of axitinib could form a pharmacological network with key genes involved in heart failure. The VEGFA-KDR pathway was found to be closely related to the differential gene expression of human heart-derived primary cardiomyocyte cell lines treated with axitinib, based on analysis of the publicly available dataset. The outcomes of animal experiments demonstrated that axitinib therapy greatly reduced cardiac fibrosis and improved TAC-induced cardiac dysfunction. Further research has shown that the expression of transforming growth factor-ß(TGF-ß) and other fibrosis genes was significantly reduced in vivo and in vitro. Conclusion: Our study provides evidence for the repurposing of axitinib to combat cardiac fibrosis, and offers new insights into the treatment of patients with HF.
