Leucine and glutamic acid attenuate the dextran sulfate sodium-induced colitis in mice by modulating the inflammatory response and energy metabolism processes.

Ulcerative colitis, a multifactorial chronic condition of the gastrointestinal tract, has seen increasing interest in dietary intervention as part of its treatment strategy. In this study, we utilized a Dextran Sodium Sulfate (DSS)-induced acute colitis mouse model to assess the impact of leucine and glutamic acid on mucosal ulceration, inflammatory cell infiltration, and proteomic alterations in colon tissue. The results indicated that both glutamic acid and leucine alleviate the symptoms of colitis by reducing the histological scores of mice colon, promoting the expression of anti-inflammatory cytokines (IL-4 and IL-10) and suppressing the expression of pro-inflammatory cytokines (TGF-β and TNF-α). A total of 8,576 proteins were detected, with 315 proteins showing significant differences between glutamic acid and model, and with 371 proteins showing significant differences between leucine and the model. These common significantly different proteins were mainly enriched with oxidative phosphorylation pathway as well as immunity.