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 randomized to Roux-en-Y gastric bypass or vertical banded 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 resulted 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.
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•RYGB and VBG induce long-term alterations in the human gut microbiome•The changes in the microbiome do not depend on BMI•RYGB and VBG have different effects on bile acid and TMAO metabolism•The surgically altered microbiome contributes to fat mass regulation
Bariatric surgery durably alters the human gut microbiome. Here, Tremaroli et al. demonstrate that two types of bariatric surgery, Roux-en-Y gastric bypass and vertical banded gastroplasty, produce long-term alterations of the gut microbiome independently of BMI and that these alterations modulate host metabolism and fat mass deposition.
This trial compared once-daily liraglutide, a glucagon-like peptide-1 analogue, with placebo in overweight or obese patients. Liraglutide was associated with clinically meaningful weight loss, a ...decrease in glycemia and risk factors, and improvement in quality of life.
The increase in the rate of obesity, a chronic disease with serious health consequences, largely explains the recent tripling in the prevalence of type 2 diabetes.
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Weight loss of 5 to 10% has been shown to reduce complications related to obesity and improve quality of life
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; however, weight loss is difficult to maintain with lifestyle intervention alone.
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Liraglutide, a glucagon-like peptide-1 analogue with 97% homology to human glucagon-like peptide-1, is approved for the treatment of type 2 diabetes at doses up to 1.8 mg once daily.
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Weight loss with liraglutide is dose-dependent up to 3.0 mg once . . .
Obesity is now recognised as a disease that is associated with serious morbidity and increased mortality. One of its main metabolic complications is type 2 diabetes, as the two conditions share key ...pathophysiological mechanisms. Weight loss is known to reverse the underlying metabolic abnormalities of type 2 diabetes and, as such, improve glucose control; loss of 15% or more of bodyweight can have a disease-modifying effect in people with type 2 diabetes, an outcome that is not attainable by any other glucose-lowering intervention. Furthermore, weight loss in this population exerts benefits that extend beyond glycaemic control to improve risk factors for cardiometabolic disease and quality of life. We review the evidence supporting the role of weight loss in the management of type 2 diabetes and propose that many patients with type 2 diabetes would benefit from having a primary weight-centric approach to diabetes treatment. We discuss the logistical challenges to implementing a new weight-centric primary treatment goal in people with type 2 diabetes.
Obesity surgery remains the most effective treatment for obesity and its complications. Weight loss was initially attributed to decreased energy absorption from the gut but has since been linked to ...reduced appetitive behavior and potentially increased energy expenditure. Implicated mechanisms associating rearrangement of the gastrointestinal tract with these metabolic outcomes include central appetite control, release of gut peptides, change in microbiota, and bile acids. However, the exact combination and timing of signals remain largely unknown. In this review, we survey recent research investigating these mechanisms, and seek to provide insights on unanswered questions over how weight loss is achieved following bariatric surgery which may eventually lead to safer, nonsurgical weight-loss interventions or combinations of medications with surgery.
Bariatric surgery is an effective therapy for obesity, hypertension and type 2 diabetes mellitus that is refractory to maximal medical therapy. Results of long-term cohort studies and emerging ...evidence from randomized clinical trials have revealed that, in addition to its beneficial effects on weight reduction, blood pressure and metabolic control, bariatric surgery might reduce the incidence and long-term progression of chronic kidney disease (CKD). Preclinical studies have provided experimental verification that bariatric surgery improves key parameters of kidney injury at the functional, structural and ultrastructural levels, and effects a programme of transcriptomic change in the kidney that is coherent with injury resolution. Multiple mechanisms explain these observations, ranging from predictable aspects of risk-factor reduction to some novel and unforeseen renoprotective benefits of surgery. Current evidence therefore supports the judicious use of bariatric surgery to treat patients with obesity, diabetes and CKD. Optimizing the benefits of surgery requires careful patient selection and consideration of how to identify and mitigate some of the challenges associated with these surgical procedures.
Bariatric surgery is an effective intervention for management of obesity through treating dysregulated appetite and achieving long-term weight loss maintenance. Moreover, significant changes in ...glucose homeostasis are observed after bariatric surgery including, in some cases, type 2 diabetes remission from the early postoperative period and postprandial hypoglycaemia. Levels of a number of gut hormones are dramatically increased from the early period after Roux-en-Y gastric bypass and sleeve gastrectomy-the two most commonly performed bariatric procedures-and they have been suggested as important mediators of the observed changes in eating behaviour and glucose homeostasis postoperatively. In this review, we summarise the current evidence from human studies on the alterations of gut hormones after bariatric surgery and their impact on clinical outcomes postoperatively. Studies which assess the role of gut hormones after bariatric surgery on food intake, hunger, satiety and glucose homeostasis through octreotide use (a non-specific inhibitor of gut hormone secretion) as well as with exendin 9-39 (a specific glucagon-like peptide-1 receptor antagonist) are reviewed. The potential use of gut hormones as biomarkers of successful outcomes of bariatric surgery is also evaluated.
The clinical efficacy of bariatric surgery has encouraged the scientific investigation of the gut as a major endocrine organ. Manipulation of gastrointestinal anatomy through surgery has been shown ...to profoundly affect the physiological and metabolic processes that control body weight and glycaemia. The most popular bariatric surgical procedures are gastric bypass, adjustable gastric banding and vertical sleeve gastrectomy. Even though these procedures were designed with the aim of causing restriction of food intake and nutrient malabsorption, evidence suggests that their contributions to weight loss are minimal. Instead, these interventions reduce body weight by decreasing hunger, increasing satiation during a meal, changing food preferences and energy expenditure. In this Review, we have explored these mechanisms as well as their mediators. The hope is that that their in-depth investigation will enable the optimization and individualization of surgical techniques, the development of equally effective but safer nonsurgical weight-loss interventions, and even the understanding of the pathophysiology of obesity itself.
Diabetes is a chronic disease that affects a vast number of individuals globally, and without optimal treatment, can lead to significant health complications. Moreover, obesity is another chronic ...disease with several complications, which includes type 2 diabetes. Bariatric surgery is a viable long-term choice for managing diseases such as obesity and type 2 diabetes. However, the impact of pharmacotherapy before and after surgery remains unclear. In this review, we assessed the use of pharmacotherapy in patients with obesity with or without diabetes before and after bariatric surgery, focusing on weight loss, glycemic control, and the risk of postoperative complications. We showed that anti-obesity medication has become increasingly important in managing obesity and type 2 diabetes, both before and after bariatric surgery. The use of preoperative pharmacotherapy can optimize patients for surgery and reduce perioperative complications. Meanwhile, postoperative pharmacotherapy can maximize weight loss, improve metabolic outcomes, and lower the risk of weight regain. Medications such as sodium-glucose cotransporter 2 (SGLT2) inhibitors, glucagon-like peptide 1 (GLP-1) receptor agonists, and combination therapies, are now very effective for treating obesity and type 2 diabetes mellitus. However, optimal timing, duration, and which combinations of pharmacotherapy to use with bariatric surgery remain unclear. Additionally, the long-term safety and efficacy of these treatments should be assessed. Integrating pharmacotherapy with bariatric surgery is a promising approach to managing obesity and type 2 diabetes, providing patients with additional options for achieving sustainable weight loss and improving their metabolic health.
•Bariatric surgery remains an important treatment for obesity and diabetes.•Anti-obesity drugs pre-/post-surgery may reduce complications and facilitate weight loss.•By combining bariatric surgery and pharmacotherapy patients may benefit more than from each entity on its own.
Improvement of glucose levels into the normal range can occur in some people living with diabetes, either spontaneously or after medical interventions, and in some cases can persist after withdrawal ...of glucose-lowering pharmacotherapy. Such sustained improvement may now be occurring more often due to newer forms of treatment. However, terminology for describing this process and objective measures for defining it are not well established, and the long-term risks versus benefits of its attainment are not well understood. To update prior discussions of this issue, an international expert group was convened by the American Diabetes Association to propose nomenclature and principles for data collection and analysis, with the goal of establishing a base of information to support future clinical guidance. This group proposed "remission" as the most appropriate descriptive term, and HbA1c <6.5% (48 mmol/mol) measured at least 3 months after cessation of glucose-lowering pharmacotherapy as the usual diagnostic criterion. The group also made suggestions for active observation of individuals experiencing a remission and discussed further questions and unmet needs regarding predictors and outcomes of remission.
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