Comprehensive proteomic analysis reveals omega-3 fatty acids to counteract endotoxin-stimulated metabolic dysregulation in porcine enterocytes

Omega-3 polyunsaturated fatty acids (n-3 PUFA), such as the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are reported to beneficially affect the intestinal immunity. The biological pathways modulated by n-3 PUFA during an infection, at the level of intestinal epithelial barrier remain elusive. To address this gap, we investigated the proteomic changes induced by n-3 PUFA in porcine enterocyte cell line (IPEC-J2), in the presence and absence of lipopolysaccharide (LPS) stress conditions using shotgun proteomics analysis integrated with RNA-sequencing technology. A total of 33, 85, and 88 differentially abundant proteins (DAPs) were identified in cells exposed to n-3 PUFA (DHA:EPA), LPS, and n-3 PUFA treatment followed by LPS stimulation, respectively. Functional annotation and pathway analysis of DAPs revealed the modulation of central carbon metabolism, including the glycolysis/gluconeogenesis, pentose phosphate pathway, and oxidative phosphorylation processes. Specifically, LPS caused metabolic dysregulation in enterocytes, which was abated upon prior treatment with n-3 PUFA. Besides, n-3 PUFA supplementation facilitated enterocyte development and lipid homeostasis. Altogether, this work for the first time comprehensively described the biological pathways regulated by n-3 PUFA in enterocytes, particularly during endotoxin-stimulated metabolic dysregulation. Additionally, this study may provide nutritional biomarkers in monitoring the intestinal health of human and animals on n-3 PUFA-based diets.