<i>Angelica sinensis</i> Polysaccharide Suppresses Pyroptosis in Myocardial Ischemia/Reperfusion Injury via the FN1/NF-κB/NLRP3 Pathway

Background Pyroptosis, a form of inflammatory programmed cell death, has recently emerged as a pivotal factor in the pathogenesis of myocardial ischemia/reperfusion (MI/R) injury. Despite its significance, effective therapeutic strategies targeting MI/R-induced pyroptosis remain elusive in current clinical practice. Previous studies have demonstrated the promising anti-inflammatory effects of Angelica sinensis polysaccharide (ASP) in the context of certain inflammatory disorders. Objectives We aimed to investigate the effects of ASP on pyroptosis in MI/R injury and elucidate the potential molecular mechanisms by combining transcriptomic analysis with complementary in vivo and in vitro experiments. Materials and methods H9c2 cells were used to establish a hypoxia/reoxygenation (H/R) model, and MI/R injury was induced in rats by ligating and releasing the left anterior coronary artery. Myocardial tissue samples were harvested for transcriptomic sequencing and bioinformatic analyses. Cardioprotective effects were evaluated through electrocardiography, echocardiography, and histological examination. Enzyme-linked immunosorbent assay (ELISA) was employed to quantify levels of inflammatory mediators. Biochemical assays were conducted to assess myocardial injury biomarkers and Caspase-1 activity. Western blotting was performed to analyze the protein expression levels of Fibronectin 1 (FN1), Nuclear factor kappa B (NF-κB) p65, phosphorylated NF-κB p65 (p-NF-κB p65), Nod-like receptor protein 3 (NLRP3), and Gasdermin-D (GSDMD). Results Pretreatment with ASP conferred potent cardioprotective effects in a rat model of MI/R injury, as evidenced by significant attenuation of infarct size, myocardial enzyme levels, and ST-segment elevation on electrocardiography, alongside notable improvements in cardiac function. Transcriptomic profiling unveiled that differentially expressed genes modulated by ASP treatment were predominantly implicated in the pyroptosis-elicited inflammatory response. Concordantly, both in vivo and in vitro experiments substantiated that ASP treatment effectively attenuated MI/R-induced pyroptosis, as manifested by diminished levels of pyroptosis-related indicators, encompassing the proportion of TUNEL-positive cells, Caspase-1 activation, GSDMD cleavage, and the liberation of pro-inflammatory cytokines. Further mechanistic investigations revealed ASP inhibition of the FN1/NF-κB/NLRP3 signaling pathway. Conclusions Our investigation, leveraging system-level transcriptomic profiling, demonstrates that ASP confers cardioprotective effects against MI/R injury through the suppression of cardiomyocyte pyroptosis, culminating from downregulation of the FN1/NF-κB/NLRP3 pathway.