A moderately elevated soy protein diet mitigates inflammatory changes in gut and in bone turnover during chronic TNBS-induced inflammatory bowel disease.

Inflammatory bowel disease is a condition that leads to gut pathologies, such as abnormal lymphatic architecture, as well as systemic comorbidities such as bone loss. Furthermore, current therapies are limited to low efficacy and incur side-effects. Dietary interventions are minimally explored, but may provide a holistic treatment to improve gut outcomes and comorbidities. Indeed, plant-based soy protein has been shown to exert anti-inflammatory effects. Here we tested the impact of a moderately elevated soy protein diet in a chronic, TNBS-induced colitis model on gut and bone inflammatory-mediated pathophysiological adaptations. Colitis was induced by intrarectal administration of TNBS. Gut histopathology was scored, and lymphatic structural changes and the local inflammatory state assessed via immunofluorescence. Additionally, the effects of gut inflammation on bone turnover and osteocyte proteins were determined via histomorphometry and immunohistochemistry, respectively. The moderately elevated soy protein diet produced holistic improvements in both colonic and bone tissues. Colon histological scores were reduced and the abnormal lymphatic architecture resolved in TNBS animals given the soy protein intervention. There were also improvements in bone formation and reduced bone resorption. Additionally, TNBS increased inflammatory cytokines such as TNF-α/RANKL in the gut and bone, which was resolved in both organ beds with dietary soy protein intervention. The moderately elevated soy protein diet mitigated gut and bone inflammation in a chronic, TNBS-induced colitis model, demonstrating the potential for soy protein as a potential anti-inflammatory lifestyle intervention for inflammatory bowel disease.