Weight loss induced by Roux-en-Y gastric bypass but not laparoscopic adjustable gastric banding increases circulating bile acids. Evaluation of the biochemical, inflammatory and oxidative profile of obese patients given clinical treatment and bariatric surgery. Increased glycine-amidated hyocholic acid correlates to improved early weight loss after sleeve gastrectomy Bile acids and gut peptide secretion after bariatric surgery: a 1-year prospective randomized pilot trial. Bile acids synthesis decreases after laparoscopic sleeve gastrectomy. Roux-en-Y Gastric Bypass and Vertical Banded Gastroplasty Induce Long-Term Changes on the Human Gut Microbiome Contributing to Fat Mass Regulation The Effect of Laparoscopic Gastric Banding Surgery on Plasma Levels of Appetite-Control, Insulinotropic, and Digestive Hormones The role of bile after Roux-en-Y gastric bypass in promoting weight loss and improving glycaemic control. Effect of bariatric surgery on airway response and lung function in obese subjects with asthma. Early Enhancements of Hepatic and Later of Peripheral Insulin Sensitivity Combined With Increased Postprandial Insulin Secretion Contribute to Improved Glycemic Control After Roux-en-Y Gastric Bypass Effects of obesity and bariatric surgery on airway hyperresponsiveness, asthma control, and inflammation. Progressive rise in gut hormone levels after Roux‐en‐Y gastric bypass suggests gut adaptation and explains altered satiety Enhanced fasting and post-prandial plasma bile acid responses after Roux-en-Y gastric bypass surgery Acute effects of gastric bypass versus gastric restrictive surgery on β-cell function and insulinotropic hormones in severely obese patients with type 2 diabetes Sleeve gastrectomy versus Roux-en-Y gastric bypass for type 2 diabetes and morbid obesity: double-blind randomised clinical trial protocol The effect of bariatric surgery on adipocytokines, renal parameters and other cardiovascular risk factors in severe and very severe obesity: 1-year follow-up. Lifestyle changes followed by bariatric surgery lower inflammatory markers and the cardiovascular risk factors C3 and C4.
CONTEXT It has been hypothesized that increased plasma bile acids ( BAs ) contribute to metabolic improvements after Roux-en-Y gastric bypass ( RYGB ) surgery by the G protein-coupled receptor TGR5-mediated effects on glucagon-like peptide-1 secretion and thyroid hormones . OBJECTIVE The objective of this study was to evaluate the importance of bariatric surgery-induced alterations in BA physiology on factors that regulate glucose homeostasis ( insulin secretion and sensitivity ) and energy metabolism ( resting energy expenditure and thyroid hormone axis ) . DESIGN , PARTICIPANTS , INTERVENTION , AND MAIN OUTCOME MEASURE : Eighteen extremely obese subjects were studied before and after 20 % weight loss , induced by either laparoscopic adjustable gastric b and ing ( LAGB ) ( n = 10 ) or RYGB surgery ( n = 8) . RESULTS Plasma BAs more than doubled after RYGB [ fasting : 1.08 ( 0.26 - 1.42 ) to 2.28 ( 1.59 - 3.28 ) μmol/L , P = .03 ; postpr and ial : 2.46 ± 1.59 to 6.00 ± 2.75 μmol/L , P = .01 ] but were either lower or did not change after LAGB [ fasting : 1.80 ( 1.49 - 2.19 ) to 0.92 ( 0.73 - 1.15 ) μmol/L , P = .02 ; postpr and ial : 3.71 ± 2.61 to 2.82 ± 1.75 μmol/L , P = .14 ] . Skeletal muscle expression of TGR5 targets , Kir6.2 and cyclooxygenase IV , increased after RYGB but not LAGB . Surgery-induced changes in BAs were associated with increased peak postpr and ial plasma glucagon-like peptide-1 ( r(2 ) = 0.509 , P = .001 ) and decreased serum TSH ( r(2 ) = 0.562 , P < .001 ) but did not correlate with the change in insulin response to a meal ( r(2 ) = 0.013 , P = .658 ) , insulin sensitivity ( assessed as insulin stimulated glucose disposal during a hyperinsulinemic-euglycemic clamp procedure ) ( r(2 ) = 0.001 , P = .995 ) , or resting energy expenditure ( r(2 ) = 0.004 , P = .807 ) . CONCLUSIONS Compared with LAGB , RYGB increases circulating BAs and TGR5 signaling , but this increase in BAs is not a significant predictor of changes in glucose homeostasis or energy metabolism BACKGROUND We investigated the biochemical and inflammatory parameters as well as biomarkers of oxidative stress in morbidly obese patients before and after bariatric surgery and clinical treatment .  METHODS This study was conducted using 60 individuals ( 10 men and 50 women ) distributed into 3 groups :  the control group , 20 non-diabetic obese patients given clinical treatment , the bariatric group , 20 non-diabetic obese patients given a Roux-en-Y bypass gastroplasty , and the bariatric diabetic group , 20 diabetic obese patients given a Roux-en-Y bypass gastroplasty .  Measurements were made before and 1 , 3 , 6 , and 12months after surgery and clinical treatment . RESULTS We showed a significant decrease in body weight , body mass index ( BMI ) and waist circumference , accompanied by a decrease in the lipid profile and glucose and glycated hemoglobin concentrations in the groups that received bariatric surgery . The concentrations of lipid peroxidation , carbonyl protein and NPSH , as well as superoxide dismutase ( SOD ) and catalase ( CAT ) activity , significantly decreased in both groups after surgery . The concentrations of inteleukin-6 , inteleukin-1 , TNF-α and resistin were also significantly lower , while adiponectin concentrations significantly increased 12months after bariatric surgery . No significant alterations were observed in the biochemical , inflammatory or oxidative parameters of the control group . CONCLUSIONS Our findings demonstrate a decrease in body mass and a subsequent improvement in biochemical , metabolic and anthropometric parameters in patients given bariatric surgery .  This may contribute to the reduction of oxidative damage in these patients and consequently a reduction in the risk of the development and progression of multiple co-morbidities associated with obesity Background Bile acids ( BAs ) are post-pr and ial hormones that play an important role in glucose and lipid homeostasis as well as energy expenditure . Total and glycine-ami date d BAs increase after sleeve gastrectomy ( SG ) and correlate to improved metabolic disease . No specific bile acid subtype has been shown conclusively to mediate the weight loss effect . Therefore , the objective of this study was to prospect ively evaluate the comprehensive changes in meal-stimulated BAs after SG and determine if a specific change in the BA profile correlates to the early weight loss response . Methods Patients were prospect ively enrolled at the University of Nebraska Medical Center who were undergoing a SG for treatment of morbid obesity . Primary and secondary plasma bile acids and their ami date d ( glycine , G- , or taurine , T- ) subtypes were measured at fasting , 30 and 60 min after a liquid meal performed pre-op , and at 6 and 12 weeks post-op . Area under the curve ( AUC ) was calculated for the hour meal test for each bile acid subtype . BAs that were significantly increased post-op were correlated to body mass index ( BMI ) loss . Results Total BA AUC was significantly increased at 6 ( p < 0.01 ) and 12 weeks post-op ( p < 0.01 ) compared to pre-operative values . The increase in total BA AUC was due to a statistically significant increase in G-BAs . Nine different BA AUC subtypes were significantly increased at both 6 and 12 weeks post-op . Increased total and G-chenodeoxycholic acid AUC was significantly correlated to the 6 week BMI loss ( p = 0.03 ) . Increased G-hyocholic acid was significantly correlated to increased weight loss at both 6 ( p = 0.05 ) and 12 weeks ( p = 0.006 ) . Conclusions SG induced an early and persistent post-pr and ial surge in multiple bile acid subtypes . Increased G-hyocholic consistently correlated with greater early BMI loss . This study provides evidence for a role of BAs in the surgical weight loss response after SG OBJECTIVE Increased delivery of bile acid salts ( BA ) to distal L-cells and altered TGR5 receptor activation may contribute to the early and substantial increases in gut peptide secretion seen after bariatric surgery . To further eluci date a potential role of BA in the secretion of GLP-1 and PYY , we analyzed plasma BA concentrations in 14 morbidly obese patients undergoing gastric bypass or sleeve gastrectomy in a prospect i ve , r and omized 1-year trial . DESIGN AND METHODS Patients  received a st and ard test meal and blood was collected before and after eating , prior to , and 1 week , 3 months , and 12 months after surgery . RESULTS Pre-surgery , basal BA concentrations were significantly lower in bariatric patients than in healthy controls . One year post-surgery , bariatric patients expressed variably increased BA concentrations ( gastric bypass patients ∼2 fold increase , P ≤ 0.05 ) . However , whereas in both patient groups , marked increases in GLP-1 and PYY and improved glycemic control was seen already 1 week and 3 months post-surgery , changes in plasma BA followed a different pattern : basal and postpr and ial plasma BA concentrations increased much slower , more progressively with significant increases only 1-year post-surgery . CONCLUSIONS Based on these findings , BA do not appear to be key mediators of the early increase in GLP-1 and PYY response in post-bariatric patients BACKGROUND Bariatric surgery is the most effective treatment alternative in morbid obesity . The mechanisms contributing to these benefits remain poorly understood . Bile acids ( BAs ) are mediators of different regulatory functions in glucose and cholesterol homeostasis and energy expenditure . Recent evidence suggests that BAs are critically important for the beneficial effects of sleeve gastrectomy ( SG ) . OBJECTIVES The aim of this study was to evaluate the effect of SG on BA synthesis . SETTING University Hospital . Santiago , Chile . METHODS Obese patients were evaluated before and after SG ( 1 , 3 , 6 , and 12 months ) . BA synthesis was evaluated through the serum marker , 7 α-hydroxy-4-cholesten-3-one ( C4 ) . Primary and secondary BA and C4 were determined by high performance liquid chromatography coupled with t and em mass spectrometry detection ( HPLC-MS/MS ) . RESULTS From June 2013 to January 2014 , 19 patients ( age 37.6±7.8 years ; BMI 35.8±3.5 kg/m(2 ) ; 79 % female ) were included in this study . Mean weight loss at 1 , 3 , 6 , and 12 months was 11.3 , 17.5 , 23.6 , and 25.4 kg , respectively , equivalent to 11.8 , 18.6 , 24.8 , and 26.9 of total body water percentage ( % TBW ) ( P<.0001 ) , respectively and 43.2 , 68.2 , 91 , and 98.8 of percentage of excess weight loss ( % EWL ) , respectively ( P<.001 ) . Serum C4 levels at baseline , 1 , 3 , 6 , and 12 months were 23.4±21.1 , 4.9±8.2 , 8.7±12.1 , 13.8±12.9 , and 18.8±16.8 ng/mL ( P<.0001 ) , respectively . Fibroblast growth factor 19 ( FGF19 ) levels at baseline , 1 , 3 , 6 , and 12 months were 71±33.3 , 130.5±66.2 , 117.8±57.2 , 134.6±91.7 , and 124.3±85.9 pg/mL ( P = .019 ) , respectively . CONCLUSION Serum levels of C4 decrease after SG , indicating a reduction in the synthesis of BA . FGF19 may play a role in decreasing BA synthesis . Further studies are necessary to characterize the effect of bariatric surgery on BA homeostasis Summary Bariatric surgery is currently the most effective procedure for the treatment of obesity . Given the role of the gut microbiota in regulating host metabolism and adiposity , we investigated the long-term effects of bariatric surgery on the microbiome of patients r and omized to Roux-en-Y gastric bypass or vertical b and ed gastroplasty and matched for weight and fat mass loss . The two surgical procedures induced similar and durable changes on the gut microbiome that were not dependent on body mass index and result ed in altered levels of fecal and circulating metabolites compared with obese controls . By colonizing germ-free mice with stools from the patients , we demonstrated that the surgically altered microbiota promoted reduced fat deposition in recipient mice . These mice also had a lower respiratory quotient , indicating decreased utilization of carbohydrates as fuel . Our results suggest that the gut microbiota may play a direct role in the reduction of adiposity observed after bariatric surgery Background We hypothesized that  laparoscopic adjustable gastric b and ing ( LAGB )  reduces weight and modulates ghrelin production , but largely spares gastrointestinal endocrine function . To examine this hypothesis , we determined plasma concentrations of appetite-control , insulinotropic , and digestive hormones in relation to LAGB . Methods Twenty-four patients undergoing LAGB were prospect ively enrolled .  Body mass index ( BMI ) was measured and blood sample s obtained at baseline and 6 and 12 months post-surgery . Plasma concentrations of leptin , acylated and total ghrelin , pancreatic polypeptide ( PP ) , insulin , glucose-dependent insulinotropic peptide ( GIP ) , active glucagon-like peptide-1 ( GLP-1 ) , gastrin , and pepsinogens I and II were measured using enzyme-linked immunoassays . Results Median percent excess weight loss ( % EWL ) over 12 months was 45.7 % with median BMI decreasing from 43.2 at baseline to 33.8 at 12 months post-surgery ( p < 0.001 ) . Median leptin levels decreased from 19.7 ng/ml at baseline to 6.9 ng/ml at 12 months post-surgery ( p < 0.001 ) . In contrast , plasma levels of acylated and total ghrelin , PP , insulin , GIP , GLP-1 , gastrin , and pepsinogen I did not change in relation to surgery ( p > 0.05 ) . Pepsinogen II levels were significantly lower 6 months after LAGB but returned to baseline levels by 12 months . Conclusions LAGB yielded substantial % EWL and a proportional decrease in plasma leptin . Our results support the hypothesis that LAGB works in part by suppressing the rise in ghrelin that normally accompanies weight loss . Unchanged concentrations of insulinotropic and digestive hormones suggest that gastrointestinal endocrine function is largely maintained in the long term Gastric bypass leads to the remission of  type 2 diabetes  independently of weight loss . Our hypothesis is that changes in bile flow due to the altered anatomy may partly explain the metabolic outcomes of the operation . We prospect ively studied 12 patients undergoing gastric bypass and six patients undergoing gastric b and ing over a 6-wk period . Plasma fibroblast growth factor (FGF)19 , stimulated by bile acid absorption in the terminal ileum , and plasma bile acids were measured . In canine and rodent models , we investigated changes in the gut hormone response after altered bile flow . FGF19 and total plasma bile acids levels increased after gastric bypass compared with no change after gastric b and ing . In the canine model , both food and bile , on their own , stimulated satiety gut hormone responses . However , when combined , the response was doubled . In rats , drainage of endogenous bile into the terminal ileum was associated with an enhanced satiety gut hormone response , reduced food intake , and lower body weight . In conclusion , after gastric bypass , bile flow is altered , leading to increased plasma bile acids , FGF19 , incretin . and satiety gut hormone concentrations . Elucidating the mechanism of action of gastric bypass surgery may lead to novel treatments for type 2 diabetes BACKGROUND Obesity is a risk factor for self-reported asthma and makes asthma management more difficult . The effects of bariatric surgery on asthma in severely obese subjects remain to be documented . METHODS In this prospect i ve study , 12 asthmatic patients with severe obesity were evaluated before , 6 and 12 months after bariatric surgery .  Each had methacholine inhalation tests , measures of expiratory flows and lung volumes , measurements of C-reactive protein and question naires on asthma medication , asthma symptoms and co-morbid conditions . Eleven severely obese patients with asthma ( considered as controls ) underwent the same evaluations . Primary endpoint was airway responsiveness to methacholine and secondary endpoints were lung volumes and markers of systemic inflammation . RESULTS Mean body mass index decreased from 51.2 to 34.4 kg/m(2 ) twelve months post-surgery . Mean PC(20 ) methacholine improved from 0.84 to 6.2 mg/ml ( P < 0.001 ) ; FEV(1 ) , FVC , FRC , FRC/TLC and ERV all improved ( P ≤ 0.006 ) . C-reactive protein decreased from 8.6 to 1.7 mg/L ( P < 0.001 ) Asthma symptoms total score was significantly reduced ( P = 0.03 ) and asthma medication needs decreased , ten patients being able to stop all asthma drugs . No significant changes of these parameters from baseline were observed in asthmatic controls . Improvements in airway responsiveness and lung volumes happened in parallel and correlated with reductions of body mass index ( r = 0.58 , P = 0.049 ) , C-reactive protein levels ( r = -0.74 , P = 0.004 ) . CONCLUSION Airway responsiveness , lung volumes and asthma severity/control markedly improved with weight loss following bariatric surgery in severely obese patients Roux-en-Y gastric bypass ( RYGB ) improves glycemic control within days after surgery , and changes in insulin sensitivity and β-cell function are likely to be involved . We studied 10 obese patients with type 2 diabetes ( T2D ) and 10 obese glucose-tolerant subjects before and 1 week , 3 months , and 1 year after RYGB . Participants were included after a preoperative diet-induced total weight loss of −9.2 ± 1.2 % . Hepatic and peripheral insulin sensitivity were assessed using the hyperinsulinemic- euglycemic clamp combined with the glucose tracer technique , and β-cell function was evaluated in response to an intravenous glucose-glucagon challenge as well as an oral glucose load . Within 1 week , RYGB  reduced basal glucose production , improved basal hepatic insulin sensitivity , and increased insulin clearance , highlighting the liver as an important organ responsible for early effects on glucose metabolism after surgery . Insulin-mediated glucose disposal and suppression of fatty acids did not improve immediately after surgery but increased at 3 months and 1 year ; this increase likely was related to the reduction in body weight . Insulin secretion increased after RYGB only in patients with T2D and only in response to oral glucose , underscoring the importance of the changed gut anatomy BACKGROUND Asthma in obese subjects is poorly understood , and these patients are often refractory to st and ard therapy . OBJECTIVES We sought to gain insights into the pathogenesis and treatment of asthma in obese subjects by determining how obesity and bariatric surgery affect asthma control , airway hyperresponsiveness ( AHR ) , and markers of asthmatic inflammation . METHODS We performed a prospect i ve study of ( 1 ) asthmatic and nonasthmatic patients undergoing bariatric surgery compared at baseline and ( 2 ) asthmatic patients followed for 12 months after bariatric surgery .  RESULTS We studied 23 asthmatic and 21 nonasthmatic patients undergoing bariatric surgery .  At baseline , asthmatic patients had lower FEV(1 ) and forced vital capacity and lower numbers of lymphocytes in bronchoalveolar lavage fluid . After surgery , asthmatic participants experienced significant improvements in asthma control ( asthma control score , 1.55 to 0.74 ; P < .0001 ) and asthma quality of life ( 4.87 to 5.87 , P < .0001 ) . Airways responsiveness to methacholine improved significantly ( methacholine PC(20 ) , 3.9 to 7.28 , P = .03 ) . There was a statistically significant interaction between IgE status and change in airways responsiveness ( P for interaction = .01 ) . The proportion of lymphocytes in bronchoalveolar lavage fluid and the production of cytokines from activated peripheral blood CD4(+ ) T cells increased significantly . CONCLUSIONS Bariatric surgery improves AHR in obese asthmatic patients with normal serum IgE levels . Weight loss has dichotomous effects on airway physiology and T-cell function typically involved in the pathogenesis of asthma , suggesting that obesity produces a unique phenotype of asthma that will require a distinct therapeutic approach Bariatric surgery is the most effective treatment for achieving long‐term weight loss in morbidly obese patients . This study investigated prospect i ve changes in gut hormones and metabolic indices after Roux‐en‐$\font\ss = cmss10 scaled 1000 \hbox{\ss Y}$ gastric bypass ( RYGB ) Abstract Objective . Exogenous bile acid ( BA ) administration is associated with beneficial metabolic effects very similar to those seen after Roux-en-Y gastric bypass ( RYGB ) surgery . Re-routing of bile into a biliopancreatic limb with simultaneous exclusion of food occurs after RYGB , with subsequent increased fasting plasma BAs . The study assessed fasting and post-pr and ial plasma BA response before and 15 months after RYGB . Material and methods . The prospect i ve study recruited 63 obese individuals ( 43 females ) , aged 43 ( 36–56 ) [ median ( IQR ) ] years .  Blood sample s were collected before and every 30 min for 120 min after a st and ard 400 kcal meal .  Fasting and post-pr and ial plasma BAs , glucagons like peptide-1 ( GLP-1 ) , –tyrosine ( PYY ) , fasting C-reactive protein ( CRP ) , glucose and insulin were measured and homeostasis model assessment -insulin resistance ( HOMA-IR ) was calculated . Results . Following RYGB , body mass index , CRP , fasting glucose and HOMA-IR decreased ; 43.7 ( 39.3–49.2 ) kg/m2 to 29.2 ( 25.1–35.0 ) kg/m2 , 7.9 ( 4.1–11.9 ) mg/L to 0.4 ( 0.2–1.0 ) mg/L , 5.5 ( 5.0–6.0 ) mmol/L to 4.6 ( 4.3–4.9 ) mmol/L and 5.9 ( 3.5–9.2 ) to 1.7 ( 1.1–2.2 ) , respectively , all P < 0.001 . Fasting total BAs , GLP-1 and PYY increased after RYGB ; 1.69 ( 0.70–2.56 ) µmol/L to 2.43 ( 1.23–3.82 ) µmol/L ( P = 0.02 ) , 6.8 ( 1.5–15.3 ) pmol/L to 17.1 ( 12.6–23.9 ) pmol/L ( P < 0.001 ) and 4.0 ( 1.0–7.1 ) pmol/L to 15.2 ( 10.0–28.3 ) pmol/L ( P < 0.001 ) , respectively . The area under the curve for post-pr and ial total BAs , total glycine-conjugated BAs , GLP-1 and PYY were greater after RYGB ; 486 ( 312–732 ) µmol/L/min versus 1012 ( 684–1921 ) µmol/L/min , 315 ( 221–466 ) µmol/L/min versus 686 ( 424–877 ) µmol/L/min , 3679 ( 3162–4537 ) pmol/L/min versus 5347 ( 4727–5781 ) pmol/L/min and 1887 ( 1423–2092 ) pmol/L/min versus 3296 ( 2534–3834 ) pmol/L/min , respectively , all P < 0.0001 . Conclusion . Weight loss following RYGB is associated with an increase in post-pr and ial plasma BA response due to larger amounts of glycine-conjugated BAs . This suggests up regulation of BA production and conjugation after RYGB Context : Hyperglycemia resolves quickly after bariatric surgery , but the underlying mechanism and the most effective type of surgery remains unclear . Objective : To examine glucose metabolism and β-cell function in patients with type 2 diabetes mellitus ( T2DM ) after two types of bariatric intervention ; Roux-en-Y gastric bypass ( RYGB ) and gastric restrictive ( GR ) surgery .  Design : Prospect i ve , nonr and omized , repeated- measures , 4-week , longitudinal clinical trial . Patients : In all , 16 T2DM patients ( 9 males and 7 females , 52±14 years , 47±9 kg m−2 , HbA1c 7.2±1.1 % ) undergoing either RYGB ( N=9 ) or GR ( N=7 ) surgery . Outcome measures : Glucose , insulin secretion , insulin sensitivity at baseline , and 1 and 4 weeks post-surgery , using hyperglycemic clamps and C-peptide modeling kinetics ; glucose , insulin secretion and gut-peptide responses to mixed meal tolerance test ( MMTT ) at baseline and 4 weeks post-surgery . Results : At 1 week post-surgery , both groups experienced a similar weight loss and reduction in fasting glucose ( P<0.01 ) . However , insulin sensitivity increased only after RYGB , ( P<0.05 ) . At 4 weeks post-surgery , weight loss remained similar for both groups , but fasting glucose was normalized only after RYGB ( 95±3 mg 100 ml−1 ) . Insulin sensitivity improved after RYGB ( P<0.01 ) and did not change with GR , whereas the disposition index remained unchanged after RYGB and increased 30 % after GR ( P=0.10 ) . The MMTT elicited a robust increase in insulin secretion , glucagon-like peptide-1 ( GLP-1 ) levels and β-cell sensitivity to glucose only after RYGB ( P<0.05 ) . Conclusion : RYGB provides a more rapid improvement in glucose regulation compared with GR . This improvement is accompanied by enhanced insulin sensitivity and β-cell responsiveness to glucose , in part because of an incretin effect Introduction Type 2 diabetes ( T2D ) in association with obesity is an increasing disease burden . Bariatric surgery is the only effective therapy for achieving remission of T2D among those with morbid obesity . It is unclear which of the two most commonly performed types of bariatric surgery , laparoscopic sleeve gastrectomy ( LSG ) and laparoscopic Roux-en-Y gastric bypass ( LRYGB ) , is most effective for obese patients with T2D . The primary objective of this study is to determine whether LSG or LRYGB is more effective in achieving HbA1c<6 % ( < 42 mmol/mol ) without the use of diabetes medication at 5 years . Methods and analysis Single-centre , double-blind ( assessor and patient ) , parallel , r and omised clinical trial ( RCT ) conducted in New Zeal and , targeting 106 patients . Eligibility criteria include age 20–55 years , T2D of at least 6 months duration and body mass index 35–65 kg/m2 for at least 5 years . R and omisation 1:1 to LSG or LRYGB , used r and om number codes disclosed to the operating surgeon after induction of anaesthesia . A st and ard medication adjustment schedule will be used during postoperative metabolic assessment s. Secondary outcomes include proportions achieving HbA1c<5.7 % ( 39 mmol/mol ) or HbA1c<6.5 % ( 48 mmol/mol ) without the use of diabetes medication , comparative weight loss , obesity-related comorbidity , operative complications , revision rate , mortality , quality of life , anxiety and depression scores . Exploratory outcomes include changes in satiety , gut hormone and gut microbiota to gain underlying mechanistic insights into T2D remission . Ethics and dissemination Ethics approval was obtained from the New Zeal and regional ethics committee ( NZ93405 ) who also provided independent safety monitoring of the trial . Study commenced in September 2011 . Recruitment completed in October 2014 . Data collection is ongoing . Results will be reported in manuscripts su bmi tted to peer- review ed journals and in presentations at national and international meetings . Trial registration numbers ACTRN12611000751976 , NCT01486680 ; Pre- results AIMS To evaluate the effect of weight loss after bariatric surgery ( BS )  on peripheral adipocytokines , renal parameters and other cardiovascular risk factors ( CVRFs ) . METHODS A total of 70 ( 41 women ) extremely obese adults were prospect ively studied before and 12 months after surgery . CONTROLS 24 ( 15 women ) normal-weight adults .  Anthropometric , biochemical and renal parameters were recorded . RESULTS Presurgery , adiponectin ( ADPN ) was lower , whereas leptin , insulin resistance , C-reactive protein , creatinine clearance and albuminuria were higher in patients than controls ( P<0.001 ) . All parameters improved postsurgery . Changes in ADPN correlated negatively with leptin , insulin resistance , albumin , C-reactive protein , and creatinine clearance . Multiple regression analysis : using changes in ADPN as the dependent variable , only changes in insulin resistance ( P=0.005 ) and albumin ( P=0.019 ) were significant independent determinants for changes in ADPN . No statistical differences were found in relation to the degree of obesity . CONCLUSION Patients changed to obesity type I after surgery . This implies a substantial improvement of CVRFs including ADPN , creatinine clearance and albuminuria . Changes in plasma ADPN correlated negatively with insulin resistance and with albuminemia but not with renal parameters . The lack of differences between different degrees of obesity suggests that the relationship between weight and CVRFs no longer exists when obesity becomes very extreme BACKGROUND Morbidly obese patients are at risk of developing insulin resistance and cardiovascular disease . Low- grade systemic inflammation is an important factor for this development . We evaluated the effect of bariatric surgery on markers of inflammation , coagulation and glucose metabolism . METHODS Ninety-seven morbidly obese patients and 17 lean subjects ( control group ) participated .  Anthropometric measurements  as well as  fasting blood sample s  were obtained at first admission , prior to surgery , and 1 year after surgery . RESULTS At admission , the morbidly obese group had significantly elevated levels of the complement components C3 and C4 compared to the lean control group ( P<0.0001 ) . Levels of C3 and C4 dropped significantly in the morbidly obese group over time ( P<0.0001 ) , and , 1 year after the operation , levels were comparable to those of the control group . The same changes were seen for markers of inflammation ( high-sensitivity C-reactive protein , tumor necrosis factor-α , interferon-γ , interleukin-1 receptor antagonist , IL-6 , and IL-13 ) , coagulation ( fibrinogen and plasminogen activator inhibitor-1 ) , and glucose metabolism ( leptin and insulin ) . There was a positive correlation between changes in C3 and body mass index , weight , coagulation parameters , inflammatory parameters , and leptin , respectively . CONCLUSIONS Bariatric surgery in morbidly obese patients  reduced weight effectively . Even more importantly , the increased levels of several risk factors associated with diabetes and cardiovascular co-morbidity normalized 1 year after surgery
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 .