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 .
Modulation of the fecal bile acid profile by gut microbiota in cirrhosis.
BACKGROUND & AIMS The 7α-dehydroxylation of primary bile acids ( BAs ) , chenodeoxycholic ( CDCA ) and cholic acid ( CA ) into the secondary BAs , lithocholic ( LCA ) and deoxycholic acid ( DCA ) , is a key function of the gut microbiota . We aim ed at study ing the linkage between fecal BAs and gut microbiota in cirrhosis since this could help underst and cirrhosis progression . METHODS Fecal microbiota were analyzed by culture-independent multitagged-pyrosequencing , fecal BAs using HPLC and serum BAs using LC-MS in controls , early ( Child A ) and advanced cirrhotics ( Child B/C ) . A subgroup of early cirrhotics underwent BA and microbiota analysis before/after eight weeks of rifaximin . RESULTS Cross-sectional : 47 cirrhotics ( 24 advanced ) and 14 controls were included . In feces , advanced cirrhotics had the lowest total , secondary , secondary / primary BA ratios , and the highest primary BAs compared to early cirrhotics and controls . Secondary fecal BAs were detectable in all controls but in a significantly lower proportion of cirrhotics ( p<0.002 ) . Serum primary BAs were higher in advanced cirrhotics compared to the rest . Cirrhotics , compared to controls , had a higher Enterobacteriaceae ( potentially pathogenic ) but lower Lachonospiraceae , Ruminococcaceae and Blautia ( 7α-dehydroxylating bacteria ) abundance . CDCA was positively correlated with Enterobacteriaceae ( r=0.57 , p<0.008 ) while Ruminococcaceae were positively correlated with DCA ( r=0.4 , p<0.05 ) . A positive correlation between Ruminococcaceae and DCA/CA ( r=0.82 , p<0.012 ) and Blautia with LCA/CDCA ( r=0.61 , p<0.03 ) was also seen . Prospect i ve study : post-rifaximin , six early cirrhotics had reduction in Veillonellaceae and in secondary / primary BA ratios . CONCLUSIONS Cirrhosis , especially advanced disease , is associated with a decreased conversion of primary to secondary fecal BAs , which is linked to abundance of key gut microbiome taxa
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 .