Molecular Features of Heatstroke Revealed by Integrated Proteomics and Metabolomics

Abstract Heatstroke is a critical medical condition marked by hyperthermia-induced immune dysregulation, endothelial damage, and organ dysfunction, yet its molecular mechanisms are not fully elucidated. In this study, serum samples from heatstroke (HS) patients and normal controls (NCs) were subjected to untargeted ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) metabolomic and quantitative proteomic analyses. Differential proteins and metabolites were identified and further analyzed through pathway enrichment, protein–protein interaction, correlation, and integrated multivariate analyses. Compared to NC, HS patients demonstrated 161 differential proteins (136 up-regulated, 25 down-regulated) and 427 differential metabolites (330 up-regulated, 97 down-regulated). The proteins B2M, MMP9, and APOB were identified as key hub proteins linked to immune activation, endothelial injury, and lipid metabolism. Metabolic changes were observed in kynurenine, purine, and mitochondrial energy metabolism pathways, while lipid metabolites showed an inverse correlation with inflammatory proteins. Integrated principal component analysis (PCA) and canonical correlation analysis (CCA) effectively distinguished HS patients from the NC. Through joint pathway analysis, 30 enriched KEGG pathways were identified, notably including cAMP signaling and arachidonic acid metabolism. These findings elucidate coordinated alterations in immune, vascular, and metabolic processes associated with heatstroke, and underscore B2M, MMP9, and ANGPTL3 as potential molecular features warranting further investigation.