Proteomic analysis of epicardial adipose tissue from heart disease patients with concomitant heart failure with preserved ejection fraction

Although epicardial adipose tissue (EAT) is known to be a major contributor to the pathogenesis of heart failure with preserved ejection fraction (HFpEF), the underlying mechanisms remain incompletely understood. This study aimed to compare the proteomic profiles of EAT from HFpEF patients and patients without HF (non-HF) and to explore candidate molecules characteristic of EAT in HFpEF.EAT samples were collected from patients who underwent cardiac surgery. Proteins were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and protein-protein interaction network analysis were conducted. The gene expression of one significant differentially expressed protein was examined by quantitative reverse transcription polymerase chain reaction.A total of 2416 proteins were detected by LC-MS/MS experiments, and expression levels were quantified for 2349 proteins. Among them, 96 proteins (including 71 upregulated proteins and 25 downregulated proteins) were significantly differentially expressed between the HFpEF (n = 5) and non-HF groups (n = 5). GO enrichment and KEGG pathway analyses revealed that these differentially expressed proteins were predominantly involved in HFpEF-related processes, including lipid metabolic disorder, inflammation, and mitochondrial dysfunction.The results of this comprehensive analysis of the EAT proteome in HFpEF patients offer new insights into the pathogenesis of HFpEF and potential molecular targets in EAT.