6. The combination therapy may loose weight by unique mechanisms of each agent; GLP-1 inhibits appetite by acting on CNS and gastrointestinal motility, whereas UDCA-enhanced circulating primary bile acids increases energy expenditure through the pathway involving G protein-coupled bile acid receptor 1 (Gpbar1, or M-Bar, TGR-5) and subsequent activation of type 2 iodothyronine deiodinase (D2) in brown adipose and muscle tissues, as reported previously.