Notch-1 in macrophages promoted the ischemia-reperfusion via modulating EZH2/HSF1/BRD4/SIRPα/SHP2 induced ROS and apoptosis in cardiomyocyte

To look into the role of Notch-1 in macrophages and the molecules it interacts with to influence the cardiomyocytes and subsequently regulates the ischemia-reperfusion (I/R) damage mechanisms. Our research methodology involved a rigorous research approach. With the help of bioinformatics analysis of the GSE66360 dataset, we found differentially expressed genes (DEGs) and pathways that were enriched in relation to acute myocardial infarction (AMI). The Sham, Model, Notch1-OE + EZH2-OE, Notch1-OE + EZH2-OE + BRD4-OE, and Notch1-OE + EZH2-OE + BRD4-OE + SHP2-KD groups included 42 male SD rats used in the in vivo investigations. Our methodologies involved cardiac ultrasonography, immunofluorescence labeling, histopathological analysis of myocardial tissue in terms of HE staining, TTC staining to determine the magnitude of myocardial infarction, and TUNEL staining to define the role of Notch-1 in macrophages in myocardial ischemia / reperfusion injury and Notch-1 signaling pathway. To clarify the molecular processes controlled by Notch-1, we used western blot analysis in in vitro studies to investigate protein expression in RAW264.7 cells across various stimulation groups.The impact of Notch-1 on oxidative stress in cardiomyocytes inside macrophages was examined using Western blot analysis and kit detection. Cardiomyocytes were stimulated using RAW264.7 cell culture supernatants from several stimulated groups. The effects of Notch-1 on cardiomyocyte death were investigated using flow cytometry to identify apoptosis and Western blot analysis to identify proteins linked to cardiomyocyte apoptosis. During a bioinformatics analysis, the results found that 108 genes whose expression levels had changed were more salient in the TNF and the NF-KB pathways. Although, it is important to note that HES1 had a negative relationship with EZH2 but NOTCH1 had a positive relationship with NICD and HES1. Notch-1 in macrophages exacerbates cardiac dysfunction, histopathological changes, and cardiomyocyte apoptosis following I/R injury, according to in vivo experiments using cardiac ultrasound, myocardial tissue histopathology HE staining, CD68 immunofluorescence staining, TTC staining for myocardial infarction area assessment, and TUNEL staining. Additionally, it mediated this impact by blocking EZH2, which released BRD4 inhibition and activated SHP2, worsening I/R damage. Western blot analysis in vitro research showed that the EZH2/HSF1/BRD4/SIRPα/SHP2 pathway was controlled by Notch-1 in macrophages. Experiments using flow cytometry and kit detection showed that Notch-1 in macrophages promoted cardiomyocyte death by inducing oxidative stress and NLRP3 inflammasome activation. By controlling the EZH2/HSF1/BRD4/SIRPα/SHP2 pathway, Notch-1 in macrophages causes excessive ROS production, which exacerbates I/R damage and causes cardiomyocyte death.