Ameliorative effect of animal bile preparations on dextran sulfate sodium-induced colitis in mice

Aim: Animal bile preparations harvested from bears, cattle, and pigs are composed of distinct types of bile acids. Given that several types of bile acid activate the farnesoid X receptor (FXR) or Takeda G-protein receptor 5 (TGR5) and thereby exert anti-inflammatory effects, we compared the effects of the three animal bile preparations on dextran sulfate sodium (DSS)-induced colitis in mice. Methods: Bear bile (BB), cattle bile (CB), and pig bile (PB) were orally given at 100 mg/kg/day during DSS treatment for 7 days. The colitis symptoms and the histological and biochemical markers of inflammatory response in the colon tissues were assessed. Results: BB, CB, and PB similarly ameliorated the colitis symptoms in DSS-treated mice. BB and CB but not PB attenuated inflammatory response in the colon tissues of DSS-treated mice. The content of the bile acids agonistic to FXR and TGR5 was significantly increased by BB and CB but not by PB. Conclusion: BB, CB, and PB are indistinguishable in ameliorating colitis symptoms in DSS-treated mice. The differences, however, in the effects of the three animal bile preparations on colon inflammation may be due to the differences in the content of anti-inflammatory bile acids.