A simple in vitro fermentation model to detect alterations in gut microbiota-dependent bile acid profiles

Abstract

A previous in vivo study showed that lincosamide antibiotics (lincomycin and clindamycin) could induce changes in the gut bacterial community, leading to significant changes in fecal bile acid profiles. Herein, our aim is to develop an animal alternative in vitro model for studying gut microbiota-dependent bile acid profiles induced by xenobiotics. The effects of lincosamides were evaluated using this model, and results obtained were verified by comparing with those of the previous in vivo study. Fecal sample processing and bile acid incubation conditions were developed and optimized using feces collected from Wistar rats, and prepared samples were incubated for 24 h with or without lincosamides. Upon treatment of the fecal gut microbiota with lincosamides primary and secondary bile acids showed obviously increased and decreased levels respectively. Moreover, the changes in bile acid profile could be linked to a reduced richness of family Erysipelotrichaceae, Bacteroidacea and Lactobacillaceae or Prevotellaceae. The consistent consequences of in vivo and in vitro provides a proof of principle for further application on elucidating effects of other xenobiotics on the gut bacterial community and related bile acid metabolism, thereby contributing to the 3Rs (replacement, reduction and refinement) in animal testing.