Glutamine Attenuates Inflammation and Oxidative Stress in Ulcerative Colitis by Suppressing Wilms' Tumor 1 Associated Protein-Mediated N6-Methyladenosine Modification of Nuclear Receptor Coactivator 3

Abstract

Ulcerative colitis (UC) is a chronic inflammatory condition. Glutamine (Gln) has shown an improved effect on UC. However, its molecular determinants are incompletely understood. NCM460 cells were stimulated with lipopolysaccharide (LPS) to generate an in vitro UC cell model, and dextran sulfate sodium (DSS)-induced UC models were established in mice. Methylated RNA immunoprecipitation (MeRIP) and messenger RNA (mRNA) stability experiments were used to validate the influence of Wilms' tumor 1-associating protein (WTAP) on nuclear receptor coactivator-3 (NCOA3) mRNA. In LPS-exposed NCM460 cells, Gln promoted NCOA3 expression and reduced WTAP expression. Gln relieved LPS-triggered inflammation, oxidative stress, and apoptosis in NCM460 cells, which were abolished by NCOA3 downregulation or WTAP upregulation. Mechanistically, Gln suppressed WTAP-mediated m6A modification of NCOA3 mRNA. WTAP reduction attenuated LPS-evoked NCM460 cell phenotype alterations, which were reversed by NCOA3 downregulation. Furthermore, Gln reduced the DAI score and histopathological changes, increased colon length, and attenuated inflammation and oxidative stress in DSS-induced UC mice, which were abrogated by WTAP increase. We showed that the WTAP/NCOA3 axis underlies the protective effect of Gln on UC, providing a rationale for Gln as a promising anti-UC agent.