Integrated bioinformatics identify the critical genes of mitophagy in myocardial ischemia- reperfusion injury

Abstract

Abstract Background: Myocardial ischemia is a prevalent cardiovascular disease with a high incidence and mortality rate. Restoring blood flow to the ischemic myocardium as soon as possible is crucial for improving patients' prognosis, but this process can lead to myocardial ischemia-reperfusion injury (MIRI). Mitophagy is a specific cellular autophagic process that has been consistently linked to various cardiovascular disorders.Nevertheless, the connection between ischemia-reperfusion and mitophagy remains unclear. This study's objective is to discern and substantiate central mitophagy-related genes associated with MIRI through bioinformatics analysis. Methods: The microarray expression profile dataset (GSE108940) was obtained from the Gene Expression Omnibus (GEO). The differentially expressed genes (DEGs) were identified using GEO2R. These DEGs were then cross-referenced with genes in the mitophagy database. Differential nucleotide sequence analysis used enrichment analysis.The DEGs were obtained through protein-protein interaction (PPI)network analysis. And the hub genes were clustered by cytoHubba and MCODE of Cytoscape software. GSEA analysis was conducted on central genes. Finally, we conducted Western blotting, immunofluorescence, and quantitative polymerase chain reaction (qPCR) analyses to corroborate the expression patterns of pivotal genes in MIRI-afflicted rats. Results: 2719 DEGs and 61 mitophagy-DEGs were obtained,followed by enrichment analyses and construction of PPI network. HSP90AA1, RPS27A, EEF2, EIF4A1, EIF2S1,HIF-1α and BNIP3 were the 7 hub genes identified by cytoHubba and MCODE of Cytoscape software. The functional clustering score of HIF-1α and BNIP3 was 9.647 by analysis of Cytoscape (MCODE). In our constructed MIRI rat model, western blot and immunofluorescence confirmed a significant elevation in the expression of HIF-1α and BNIP3, along with a significant increase in the ratio of LC3II to LC3I. Finally,qPCR confirmed that expression of HIF-1α, BNIP3 and LC3 mRNA in MIRI group was elevated significantly. Conclusions: Seven central genes among the mitophagy-related DEGs have been pinpointed, potentially holding pivotal significance in MIRI, which indicated that HIF-1α/BNIP3 pathway of mitophag was correlated with pathogenesis of MIRI. Mitophagy may play an important role in MIRI.This research will offer valuable insights into the underlying mechanisms and potential therapeutic targets, which can be explored in future studies.