The findings support the effects of BAs on satiety , lipid and cholesterol metabolism , incretins and glucose homoeostasis , energy metabolism , gut microbiota and endoplasmic reticulum stress following bariatric surgery .
Many of these metabolic effects are modulated through the BA receptors FXR and TGR5 .
We also explore a possible link between BAs and carcinogenesis following bariatric surgery .
Conclusions : Overall there is good evidence to support the role of BAs in the metabolic effects of bariatric surgery through the above mechanisms .
BAs could serve as a novel therapeutic pharmacological target for the treatment of obesity and its associated co-morbidities
Background : Bariatric surgery is currently the most efficacious treatment for obesity and its associated metabolic co-morbidities , such as diabetes .
The metabolic improvements occur through both weight-dependent and weight-independent mechanisms .
Bile acids ( BAs ) have emerged as key signalling molecules that have a central role in modulating many of the physiological effects seen after bariatric surgery .
This systematic review assesses the evidence from both human and animal studies for the role of BAs in reducing the metabolic complications of obesity following bariatric surgery .
Vertical sleeve gastrectomy reduces hepatic steatosis while increasing serum bile acids in a weight-loss-independent manner
Objective Our objective was to investigate the role of bile acids in  hepatic steatosis reduction after vertical sleeve gastrectomy ( VSG ) . Design and Methods  High fat diet ( HFD ) induced obese C57Bl/6 mice were r and omized to : VSG , Sham operation ( Sham ) , Sham operation with pair feeding to VSG ( Sham-PF ) , or non-surgical controls ( Naïve ) . All mice were on HFD until sacrifice . Mice were observed post-surgery and data for body weight , body composition , metabolic parameters , serum bile acid level and composition were collected . Further hepatic gene expression by RNAseq and RT-PCR analysis was assessed . Results VSG and Sham-PF mice lost equal weight post-surgery while VSG mice had the lowest hepatic triglyceride content at sacrifice . The VSG mice had elevated serum bile acid levels that positively correlated with maximal weight loss . Serum bile composition in the VSG group had increased cholic and tauroursodeoxycholic acid . These bile acid composition changes in VSG mice explained observed downregulation of hepatic lipogenic and bile acid synthetic genes . Conclusion VSG in obese mice results in greater hepatic steatosis reduction than seen with caloric restriction alone . VSG surgery increases serum bile acids that correlate with weight lost post-surgery and changes serum bile composition that could explain suppression of hepatic genes responsible for lipogenesis
The findings support the effects of BAs on satiety , lipid and cholesterol metabolism , incretins and glucose homoeostasis , energy metabolism , gut microbiota and endoplasmic reticulum stress following bariatric surgery .
Many of these metabolic effects are modulated through the BA receptors FXR and TGR5 .
We also explore a possible link between BAs and carcinogenesis following bariatric surgery .
Conclusions : Overall there is good evidence to support the role of BAs in the metabolic effects of bariatric surgery through the above mechanisms .
BAs could serve as a novel therapeutic pharmacological target for the treatment of obesity and its associated co-morbidities
Background : Bariatric surgery is currently the most efficacious treatment for obesity and its associated metabolic co-morbidities , such as diabetes .
The metabolic improvements occur through both weight-dependent and weight-independent mechanisms .
Bile acids ( BAs ) have emerged as key signalling molecules that have a central role in modulating many of the physiological effects seen after bariatric surgery .
This systematic review assesses the evidence from both human and animal studies for the role of BAs in reducing the metabolic complications of obesity following bariatric surgery .