Antioxidative and Immunomodulatory Effects of A-Lipoic Acid in Rat Colitis Model Induced by Acetic Acid

Abstract

Aim: Benefit of alpha-Lipoic acid (ALA) was previously shown in rat-colitis model via suppression of neutrophil accumulation, preservation of endogenous glutathione and inhibition of reactive oxidant generation. Ulcerative colitis is a chronic inflammatory condition of the colon and cytokines (such as TNF-alpha, IL-1 beta and TGF-beta) are crucial components of these inflammatory pathways. Hence, the present study was undertaken to evaluate the antioxidative and immunomodulatory effects of ALA on experimental colitis model induced by acetic acid in Wistar albino rats. Methods: Mice received either a control diet or ALA-supplemented diet for 14 d. Colitis was induced by acetic acid administration at 7th day. Mucosal damage and the activation of immune cells and cytokines were determined by macroscopic score, histological score, tissue cytokine levels (TNF-alpha, IL-1 beta and TGF-beta). Anti-oxidant effect of ALA was determined by Malondialdehyde, and total antioxidative status. Results: Disease activity Index was significantly higher in colitis group compared to control, ALA and ALA-colitis groups (p<0.001). No significant difference was found between DAI of control, ALA and ALA-colitis groups. The inflammatory mediators, TNF-alpha and IL-1 beta, and MDA were elevated in colitis group compared to other groups (p<0.001, p<0.001 respectively). TGF-beta and total antioxidative status were significantly lower in colitis group (p<0.001). Conclusion: ALA may possibly have some therapeutic usefulness in the management of ulcerative colitis.