Multi-Omics Reveal the Improvements of Nutrient Digestion, Absorption, and Metabolism and Intestinal Function via GABA Supplementation in Weanling Piglets

Abstract

As a nonprotein amino acid, γ-aminobutyric acid (GABA) plays a vital role in intestinal function. This study aimed to investigate the underlying mechanisms by which GABA affects intestinal health in piglets. The results showed that GABA significantly improved growth performance, reduced diarrhea, and mitigated inflammation. Additionally, microbiota profiling revealed enhanced diversity and changes in the composition of ileal bacteria and fungi. Metabolomic and transcriptomic analyses suggested that dietary supplementation with GABA could affect several pathways related to nutrient digestion and absorption. We further confirmed that GABA increased the activities of lipase and trypsin, as well as elevated the expression of tight junction proteins. Therefore, we propose that dietary 80 mg/kg GABA supplementation may enhance nutrient digestion and absorption, thereby improving intestinal function in weanling piglets.