Taurine alleviates colitis by regulating oxidative stress, inflammatory responses, ER stress, and apoptotic pathways

Colitis is an inflammatory condition affecting the colon, characterized by oxidative stress, ER stress, and apoptosis, which leads to severe tissue damage. Existing treatments are associated with significant side effects, necessitating the exploration of alternative therapeutic agents. Taurine is a commonly consumed bioactive sulfur-containing amino acid, recognized for its cyto-protective property. In this study, we are using a male Wistar rat model for 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis and treated them with taurine. Colitis development was indicated by repeated loose bloody stools, reduced appetite, and weight loss. Macroscopic examination revealed an inflamed colon surface with ulcerations, while histopathology showed a destroyed crypt structure and damage to the epithelial and mucosal layers in the colitis-affected rats. However, taurine administration reverses such adverse effects of colitis. Taurine significantly mitigates the oxidative stress by upregulating the level of anti-oxidant molecules, such as CAT, GST and SOD, which were significantly down-regulated in colitis. In addition, increased levels of inflammatory molecules (TNF-α, IL- 1β, IL- 6, MCP- 1, ICAM- 1, and VCAM- 1) in colitis were reduced by taurine supplementation. Furthermore, we observed taurine alleviates colitis induced up-regulation of important endoplasmic reticulum (ER) stress markers like, CHOP, GRP78, calpain 1, and caspase 12. We have also demonstrated that taurine supplementation reverses colitis induced apoptosis by assessing the modulation of apoptotic markers (Bax, Bcl- 2, caspase 9 and caspase 3). Furthermore, no instances of toxicity from taurine were observed. Thus, taurine shows a potential to be utilized as a therapeutic agent for colitis with further detailed investigation.