Clematichinenoside AR ameliorated spontaneous colitis in Il-10^-/- mice associated with improving the intestinal...

Clematichinenoside AR (AR) is a saponin extracted for traditional Chinese medicine with the effects of improving the expression of tight junction (TJ) proteins and mediating anti-inflammatory activities. However, its effect on Crohn's disease (CD) is still unknown. We aimed to investigate the impact of AR on CD-like colitis and determine the mechanism underlying its effects.

Interleukin-10 gene knockout (Il-10^-/-) mice (male, fifteen weeks old) with spontaneous colitis were allocated to the positive control and AR-treated (32 mg/kg AR administered every other day by gavage for 4 weeks) groups. Wild-type (WT) mice (male, fifteen weeks old) composed the negative control group. The effects of AR on intestinal barrier function and structure and T cell responses as well as the potential mechanisms underlying these effects were investigated.

AR treatment significantly improved spontaneous colitis in Il-10^-/- mice as demonstrated by reductions in the inflammatory score, disease activity index (DAI) and levels of inflammatory factors. The effects of AR on colitis in Il-10^-/- mice were related to protecting intestinal barrier function and maintaining immune system homeostasis (regulatory T cell (Treg)/T helper 17 (Th17) cell balance). The anticolitis effect of AR may partly act by downregulating PI3K/Akt signaling.

AR may have therapeutic potential for treating CD in humans.