Inhibitory Effect of β-Sitosterol on TNBS-Induced Colitis in Mice

beta-Sitosterol, a common sterol in herbal medicines, exhibits anti-inflammatory effects beneficial in the treatment of lung inflammation, asthma, and bronchospasm. To evaluate whether beta-sitosterol also has anticolitic benefits, we tested the effect of beta-sitosterol on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. beta-Sitosterol inhibited colon shortening and led to lowered macroscopic scores and myeloperoxidase activity in TNBS-treated colitic mice. beta-Sitosterol also inhibited the expression of proinflammatory cytokines TNF-alpha, IL-1 beta, and IL-6, and an inflammatory enzyme, cyclooxygenase (COX)-2, in the colons of TNBS-induced colitic mice, as well as the activation of NF-kappa B. Based on these findings, beta-sitosterol may ameliorate colitis by inhibiting the NF-kappa B pathway.