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 .
Dietary intervention impact on gut microbial gene richness
Complex gene – environment interactions are considered important in the development of obesity . The composition of the gut microbiota can determine the efficacy of energy harvest from food and changes in dietary composition have been associated with changes in the composition of gut microbial population s. The capacity to explore microbiota composition was markedly improved by the development of metagenomic approaches , which have already allowed production of the first human gut microbial gene catalogue and stratifying individuals by their gut genomic profile into different enterotypes , but the analyses were carried out mainly in non-intervention setting s. To investigate the temporal relationships between food intake , gut microbiota and metabolic and inflammatory phenotypes , we conducted diet-induced weight-loss and weight-stabilization interventions in a study sample of 38 obese and 11 overweight individuals . Here we report that individuals with reduced microbial gene richness ( 40 % ) present more pronounced dys-metabolism and low- grade inflammation , as observed concomitantly in the accompanying paper . Dietary intervention  improves low gene richness and clinical phenotypes , but seems to be less efficient for inflammation variables in individuals with lower gene richness . Low gene richness may therefore have predictive potential for the efficacy of intervention
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 .