Indole-3-carbinol exerts sex-specific effects in murine colitis

Due to the severe adverse effects that can accompany conventional therapies for Crohn's disease, the search for natural complementary therapies has increased dramatically in recent years. Indole-3-carbinol (I3C), a constituent of cruciferous vegetables, possesses anti-inflammatory properties; however, its effects on intestinal inflammation have yet to be evaluated. To test the hypothesis that I3C dampens intestinal inflammation, C57BI/6 mice were treated with I3C and exposed to 2,4,6-trinitrobenzenesulfonic acid (TNBS) to induce colitis. Several parameters of disease severity and inflammation were subsequently evaluated. I3C dampened the disease severity, as indicated by decreased body weight loss and decreased severity of clinical signs. Interestingly, this effect was observed in female but not male mice, which displayed a trend towards exacerbated colitis. Differential effects were observed in the profiles of cytokine production, as the production of pro-inflammatory cytokines was increased in males. The sex-specific effect of I3C in TNBS-induced colitis is a novel finding and warrants further investigation since this is a common dietary compound and is also available commercially.