GPBAR1 and metabolic disease: The known functions of TGR5 in vivo have recently expanded rapidly from initial roles in regulating energy homeostasis and metabolic diseases to also participating in inflammation and carcinogenesis (Cipriani et al., 2011; Pols et al., 2011; Wang et al., 2011; Cao et al., 2013; Guo et al., 2015).