Ginsenoside Rh2 alleviates dextran sulfate sodium-induced colitis via augmenting TGFβ signaling.

Ginsenoside Rh2 (GRh2) has been reported to have therapeutic effects on various diseases. However, whether it may also affect the recovery from ulcerative colitis remains unknown. Here we induced colitis in mice by dextran sulfate sodium (DSS) administration, and then treated the mice with GRh2. We found that GRh2-treated mice showed significant alleviation of the DSS-induced colitis. Moreover, significant increase in the activity of TGFβ signaling was detected in the GRh2-treated colon that had received DSS. To investigate whether there is a causative link among GRh2 treatment, TGFβ signaling augment and the cure of colitis, we gave the DSS-treated mice a combination of GRh2 and a specific TGFβ receptor I inhibitor, SB431542. SB431542 significantly decreased the activation of TGFβ signaling in the colon from the GRh2-administrated mice, and consequently attenuated the therapeutic effect of GRh2. Our data thus demonstrate that GRh2 may alleviate DSS-induced colitis via augmenting TGFβ signaling.