Bariatric surgery: effects on glucose homeostasis

G protein-coupled receptors driven intestinal glucagon-like peptide-1 reprogramming for obesity: Hope or hype?

'Globesity' is a foremost challenge to the healthcare system. The limited efficacy and adverse effects of available oral pharmacotherapies pose a significant obstacle in the fight against obesity. The biology of the leading incretin hormone glucagon-like-peptide-1 (GLP-1) has been highly captivated during the last decade owing to its multisystemic pleiotropic clinical outcomes beyond inherent glucoregulatory action. That fostered a pharmaceutical interest in synthetic GLP-1 analogues to tackle type-2 diabetes (T2D), obesity and related complications. Besides, mechanistic insights on metabolic surgeries allude to an incretin-based hormonal combination strategy for weight loss that emerged as a forerunner for the discovery of injectable 'unimolecular poly-incretin-agonist' therapies. Physiologically, intestinal enteroendocrine L-cells (EECs) are the prominent endogenous source of GLP-1 peptide. Despite comprehending the potential of various G protein-coupled receptors (GPCRs) to stimulate endogenous GLP-1 secretion, decades of translational GPCR research have failed to yield regulatory-approved endogenous GLP-1 secretagogue oral therapy. Lately, a dual/poly-GPCR agonism strategy has emerged as an alternative approach to the traditional mono-GPCR concept. This review aims to gain a comprehensive understanding by revisiting the pharmacology of a few potential GPCR-based complementary avenues that have drawn attention to the design of orally active poly-GPCR agonist therapy. The merits, challenges and recent developments that may aid future poly-GPCR drug discovery are critically discussed. Subsequently, we project the mechanism-based therapeutic potential and limitations of oral poly-GPCR agonism strategy to augment intestinal GLP-1 for weight loss. We further extend our discussion to compare the poly-GPCR agonism approach over invasive surgical and injectable GLP-1-based regimens currently in clinical practice for obesity.

Cost-Effectiveness of Bariatric Surgery in Patients Living with Obesity and Type 2 Diabetes

Aims

The favourable effects of bariatric surgeries on body weight reduction and glucose control have been demonstrated in several studies. Additionally, the cost-effectiveness of bariatric surgeries has been confirmed in several analyses. The aim of the current analysis was to demonstrate the cost-effectiveness of bariatric surgeries in obese patients with type 2 diabetes in Hungary compared to conventional diabetes treatments based on economic modelling of published clinical trial results.

Materials and Methods

Patients entered the simulation model at the age of 45 with body mass index (BMI) ≥ 30 kg/m2 and type 2 diabetes. The model was performed from the public payer's perspective, comparing sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) procedures to conventional care of diabetes. The results were provided separately for three BMI categories.

Results

The base-case analysis demonstrated that both surgery types were dominant; i.e., they saved 17 064 to 24 384 Euro public payer expenditures and resulted in improved health outcomes (1.36 to 1.50 quality-adjusted life years gain (QALY)) in the three BMI categories. Bariatric surgeries extended the life expectancy and the disease-free survival times of all the investigated diabetes complications. All the scenario analyses confirmed the robustness of the base-case analysis, such that bariatric surgeries remained dominant compared to conventional diabetes treatments.

Conclusion

The results of this cost-effectiveness analysis highlight the importance of bariatric surgeries as alternatives to conventional diabetes treatments in the obese population. Therefore, it is strongly recommended that a wider population has access to these surgeries in Hungary.

Impact of Bariatric Surgery on the Stability of the Genetic Material, Oxidation, and Repair of DNA and Telomere Lengths

Obesity causes genetic instability, which plays a key-role in the etiology of cancer and aging. We investigated the impact of bariatric surgery (BS) on DNA repair, oxidative DNA damage, telomere lengths, alterations of antioxidant enzymes and, selected proteins which reflect inflammation. The study was realized with BS patients (n = 35). DNA damage, base oxidation, BER, and NER were measured before and 1 month and 6 months after surgery with the single-cell gel electrophoresis technique. SOD and GPx were quantified spectrophotometrically, malondealdehyde (MDA) was quantified by HPLC. Telomere lengths were determined with qPCR, and plasma proteome profiling was performed with high-resolution mass spectrophotometry. Six months after the operations, reduction of body weight by 27.5% was observed. DNA damage decreased after this period, this effect was paralleled by reduced formation of oxidized DNA bases, a decline in the MDA levels and of BER and NER, and an increase in the telomere lengths. The activities of antioxidant enzymes were not altered. Clear downregulation of certain proteins (CRP, SAA1) which reflect inflammation and cancer risks was observed. Our findings show that BS causes reduced oxidative damage of DNA bases, possibly as a consequence of reduction of inflammation and lipid peroxidation, and indicate that the surgery has beneficial long-term health effects.

Not Control but Conquest: Strategies for the Remission of Type 2 Diabetes Mellitus

A durable normoglycemic state was observed in several studies that treated type 2 diabetes mellitus (T2DM) patients through metabolic surgery, intensive therapeutic intervention, or significant lifestyle modification, and it was confirmed that the functional β-cell mass was also restored to a normal level. Therefore, expert consensus introduced the concept of remission as a common term to express this phenomenon in 2009. Throughout this article, we introduce the recently updated consensus statement on the remission of T2DM in 2021 and share our perspective on the remission of diabetes. There is a need for more research on remission in Korea as well as in Western countries. Remission appears to be prompted by proactive treatment for hyperglycemia and significant weight loss prior to irreversible β-cell changes. T2DM is not a diagnosis for vulnerable individuals to helplessly accept. We attempt to explain how remission of T2DM can be achieved through a personalized approach. It may be necessary to change the concept of T2DM towards that of an urgent condition that requires rapid intervention rather than a chronic, progressive disease. We must grasp this paradigm shift in our understanding of T2DM for the benefit of our patients as endocrine experts.

Altered Glucose Metabolism and Glucose Transporters in Systemic Organs After Bariatric Surgery

The Roux-en-Y gastric bypass (RYGB) is highly effective in the remission of obesity and associated diabetes. The mechanisms underlying obesity and type 2 diabetes mellitus remission after RYGB remain unclear. This study aimed to evaluate the changes in continuous dynamic FDG uptake patterns after RYGB and examine the correlation between glucose metabolism and its transporters in variable endocrine organs using ¹⁸F-fluoro-2-deoxyglucose positron emission tomography images. Increased glucose metabolism in specific organs, such as the small intestine and various fat tissues, is closely associated with improved glycemic control after RYGB. In Otsuka Long-Evans Tokushima Fatty rats fed with high-fat diets, RYGB operation increases intestine glucose transporter expression and various fat tissues' glucose transporters, which are not affected by insulin. The fasting glucose decrement was significantly associated with RYGB, sustained weight loss, post-RYGB oral glucose tolerance test (OGTT) area under the curve (AUC), glucose transporter, or glycolytic enzymes in the small bowel and various fat tissues. High intestinal glucose metabolism and white adipose tissue-dependent glucose metabolism correlated with metabolic benefit after RYGB. These findings suggest that the newly developed glucose biodistribution accompanied by increased glucose transporters is a mechanism associated with the systemic effect of RYGB.

IGFBP-2 partly mediates the early metabolic improvements caused by bariatric surgery

Insulin-like growth factor-binding protein (IGFBP)-2 is a circulating biomarker of cardiometabolic health. Here, we report that circulating IGFBP-2 concentrations robustly increase after different bariatric procedures in humans, reaching higher levels after biliopancreatic diversion with duodenal switch (BPD-DS) than after Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). This increase is closely associated with insulin sensitization. In mice and rats, BPD-DS and RYGB operations also increase circulating IGFBP-2 levels, which are not affected by SG or caloric restriction. In mice, Igfbp2 deficiency significantly impairs surgery-induced loss in adiposity and early improvement in insulin sensitivity but does not affect long-term enhancement in glucose homeostasis. This study demonstrates that the modulation of circulating IGFBP-2 may play a role in the early improvement of insulin sensitivity and loss of adiposity brought about by bariatric surgery.

Metabolic adaptations after bariatric surgery: adipokines, myokines and hepatokines

This review addresses the impact of bariatric surgery on the endocrine aspects of white adipose tissue, muscle and the liver. We describe literature supporting the notion that adipokines, myokines and hepatokines likely act in concert and drive many of the long-term metabolic improvements following surgery. Circulating adiponectin is increased while secretion of pro-inflammatory interleukins (1, 6 and 8) decreases, alongside leptin secretion. The metabolic improvements observed in the muscle might relate to reduction of myokines contributing to insulin resistance (including myostatin, brain-derived neurotrophic factor and fibroblast growth factor-21). Subject to exception, hepatokine secretion is generally increased (such as insulin-like growth factor-binding protein 2, adropin and sex hormone-binding globulin). In conclusion, bariatric surgery restores metabolic functions by enhancing the time-dependent secretion of anti-inflammatory, insulin-sensitizing and antilipemic factors. Further research is needed to understand the molecular mechanisms by which these factors may trigger the remission of obesity-related comorbidities following bariatric surgery.

Does Bariatric Surgery Affect Intraocular Pressure?

PURPOSE

The effect of body mass index (BMI) reduction following bariatric surgery on intraocular pressure (IOP) is not well established. We evaluated association between BMI reduction and IOP measurements and other ocular and metabolic parameters 1 year after bariatric surgery.

MATERIALS AND METHODS

A retrospective study with over 1-year follow-up on patients who underwent weight reduction bariatric surgery between January 2016 and December 2016 at Wolfson Medical Center, Israel. Patient data was extracted from outpatient's bariatric and ocular clinic records. Metabolic, ocular, and clinical parameters were assessed including BMI changes, IOP, central corneal and retinal nerve fiber layer thickness, optical coherence tomography, and biometry results.

RESULTS

Of 22 bariatric surgery patients, 15 underwent laparoscopic sleeve gastrectomy (LSG) and 7 laparoscopic mini gastric bypass (MGB). All were followed up for over 1 year after surgery. Average BMI decreased from 41.9 ± 7.3 to 25.5 ± 5.7 kg/m² at 1-year follow-up (p < 0.001). Mean IOP decreased significantly by 21% after 1 year (p < 0.001). Decrease in IOP 1 year after surgery was correlated with decrease in IOP at 3-month follow-up (r = 0.677, p = 0.001), preoperative IOP (r = 0.837, p < 0.001), and corneal thickness (r = 0.589, p = 0.006), with no correlation between reduction in IOP and baseline weight, BMI, or the reduction in either (p > 0.05). Central corneal thickness and retinal nerve fiber layer thickness were also significantly decreased (p = 0.038) and (p = 0.018), respectively.

CONCLUSION

BMI reduction achieved by bariatric surgery was associated with significant and continued decline in IOP beyond 1 year after surgery. Clinical implications highlight the importance of considering bariatric surgery in patients with ocular hypertension.

Surgical outcome of laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass for resolution of type 2 diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

Bariatric procedures are considered superior to medical therapies in managing type 2 diabetes mellitus (T2DM). Laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG) are the most commonly used procedures for weight loss and comorbidity resolution worldwide. However, it is not yet known whether the degree of T2DM is influenced by the choice of bariatric procedure.

AIM

To quantitatively compare T2DM resolution over 1-5 years follow-up by LRYGB and LSG in morbidly obese patients.

METHODS

We searched the selected databases for full-text English language clinical studies that compared the effectiveness of LRYGB and LSG for T2DM resolution. Review manager 5.3 was used for data analysis, and the overall effect summary was represented in a forest plot.

RESULTS

From 1,650 titles retrieved by an initial search, we selected nine studies for this research. We found insignificant differences for T2DM resolution by LRYGB and LSG, with an odds ratio of 0.93 (95%CI: 0.64-1.35, Z statistics = 0.38, P = 0.71). Additionally, subset analyses for T2DM resolution showed insignificant differences after 24 mo (χ 2 = 1.24, df = 4, P = 0.87, overall Z effect = 0.23), 36 mo (χ 2 = 0.41, df = 2, P = 0.81, overall Z effect = 0.51), and 60 mo (χ 2 = 4.75, df = 3, P = 0.19, overall Z effect = 1.20) by LRYGB and LSG. This study reports a T2DM remission rate of 82.3% by LRYGB and 80.7% by LSG.

CONCLUSION

This study reports similar T2DM resolution rates by both LRYGB and LSG during 1-5 years of follow-up. However, long-term follow-up of 10 years is needed to further substantiate these findings.

Reduction of intraocular pressure after bariatric surgery

PURPOSE

To investigate the effects of bariatric surgery on intraocular pressure (IOP).

METHODS

We prospectively enroled consecutive obese patients who underwent a laparoscopic sleeve gastrectomy procedure. We measured IOP prior to and 3-6 months following surgery and recorded medical and demographical parameters.

RESULTS

Thirty-two patients completed all evaluations. Mean age was 40.5 ± 12 and 24 (75%) were men. Following surgery, mean body-mass index (BMI) decreased from 42 ± 6 to 31 ± 8 (p < 0.001). The mean IOP decreased from 16.9 ± 4 mmHg to 14.1 ± 3 mmHg (p < 0.001). The extent of IOP reduction was correlated with the baseline IOP (Pearson r = 0.737, p < 0.001) and central corneal thickness (Pearson r = 0.453, p = 0.010).

CONCLUSION

In a cohort of obese individuals undergoing sleeve gastrectomy, there was a significant decrease in IOP measured 3-6 months after the procedure. Our results suggest that significant weight loss could have beneficial effects on IOP in obese individuals with ocular hypertension which might enable avoidance of antiglaucoma medications. The high likelihood of a reduction in IOP should be taken into account when considering bariatric surgery in such patients.

The FGF21 response to fructose predicts metabolic health and persists after bariatric surgery in obese humans

OBJECTIVE

Fructose consumption has been implicated in the development of obesity and insulin resistance. Emerging evidence shows that fibroblast growth factor 21 (FGF21) has beneficial effects on glucose, lipid, and energy metabolism and may also mediate an adaptive response to fructose ingestion. Fructose acutely stimulates circulating FGF21 consistent with a hormonal response. We aimed to evaluate whether fructose-induced FGF21 secretion is linked to metabolic outcomes in obese humans before and after bariatric surgery-induced weight loss.

METHODS

We recruited 40 Roux-en-Y gastric bypass patients and assessed the serum FGF21 response to fructose (75-g fructose tolerance test) and basal and insulin-mediated glucose and lipid fluxes during a 2-step hyperinsulinemic-euglycemic clamp with infusion of [6,6-²H₂] glucose and [1,1,2,3,3-²H₅] glycerol. Liver biopsies were obtained during bariatric surgery. Nineteen subjects underwent the same assessments at 1-year follow-up.

RESULTS

Serum FGF21 increased 3-fold at 120 min after fructose ingestion and returned to basal levels at 300 min. Neither basal FGF21 nor the fructose-FGF21 response correlated with liver fat content or liver histopathology, but increased levels were associated with elevated endogenous glucose production, increased lipolysis, and peripheral/muscle insulin resistance. At 1-year follow-up, subjects had lost 28 ± 6% of body weight and improved in all metabolic outcomes, but fructose-stimulated FGF21 dynamics did not markedly differ from the pre-surgical state. The association between increased basal and stimulated FGF21 levels with poor metabolic health was no longer present after weight loss.

CONCLUSIONS

Fructose ingestion in obese humans stimulates FGF21 secretion, and this response is related to systemic metabolism. Further studies are needed to establish if FGF21 signaling is (patho)physiologically involved in fructose metabolism and metabolic health.

THE ROLE OF METABOLIC SURGERY FOR PATIENTS WITH OBESITY GRADE I AND TYPE 2 DIABETES NOT CONTROLLED CLINICALLY

Introduction

Even considering the advance of the medical treatment in the last 20 years with new and more effective drugs, the outcomes are still disappointing as the control of obesity and type 2 Diabetes Mellitus (T2DM) with a large number of patients under the medical treatment still not reaching the desired outcomes.

Objective:

To present a Metabolic Risk Score to better guide the surgical indication for T2DM patients with body mass index (BMI) where surgery for obesity is still controversial.

Method:

Research was conducted in Pubmed, Medline, Pubmed Central, Scielo and Lilacs between 2003-2015 correlating headings: metabolic surgery, obesity and type 2 diabetes mellitus. In addition, representatives of the societies involved, as an expert panel, issued opinions.

Results:

Forty-five related articles were analyzed by evidence-based medicine criteria. Grouped opinions sought to answer the following questions: Why metabolic and not bariatric surgery?; Mechanisms involved in glycemic control; BMI as a single criterion for surgical indication for uncontrolled T2DM; Results of metabolic surgery studies in BMI<35 kg/m²; Safety of metabolic surgery in patients with BMI<35 kg/m²; Long-term effects of surgery in patients with baseline BMI<35 kg/m² and Proposal for a Metabolic Risk Score.

Conclusion:

Metabolic surgery has well-defined mechanisms of action both in experimental and human studies. Gastrointestinal interventions in T2DM patients with IMC≤35 kg/m² has similar safety and efficacy when compared to groups with greater BMIs, leading to the improvement of diabetes in a superior manner than clinical treatment and lifestyle changes, in part through weight loss independent mechanisms . There is no correlation between baseline BMI and weight loss in the long term with the success rate after any surgical treatment. Gastrointestinal surgery treatment may be an option for patients with T2DM without adequate clinical control, with a BMI between 30 and 35, after thorough evaluation following the parameters detailed in Metabolic Risk Score defined by the surgical societies. Roux-en-Y gastric bypass (RYGB), because of its well known safety and efficacy and longer follow-up studies, is the main surgical technique indicated for patients eligible for surgery through the Metabolic Risk Score. The vertical sleeve gastrectomy may be considered if there is an absolute contraindication for the RYGB. T2DM patients should be evaluated by the multiprofessional team that will assess surgical eligibility, preoperative work up, follow up and long term monitoring for micro and macrovascular complications.

The Impact of Bariatric Surgery on Type 2 Diabetes Mellitus and the Management of Hypoglycemic Events

Recent studies discussed the benefit of bariatric surgery on obese patients diagnosed with type 2 diabetes mellitus (T2DM). Several factors play an essential role in predicting the impact of bariatric surgery on T2DM, such as ABCD score (age, BMI, C-peptide, and duration of the disease), HbA1c, and fasting blood glucose, incretins [glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP)]. DiaRem score known to include factors such as age, HbA1c, medication, and insulin usage used to predict the remission of T2DM, but it has some limitations. An extensive literature search was conducted on PubMed and Google Scholar using keywords such as gastric bypass, T2DM, bariatric surgery, GLP-1, GIP, and post bariatric hypoglycemia. Restrictive-malabsorptive procedures are most effective in treating T2DM patients based on changes induced in appetite through regulation of gastrointestinal hormones, with decreased hunger and increased satiation. We provide a review of bariatric surgery influence on T2DM and management of post-intervention hypoglycemic events. Post-bariatric surgery hypoglycemia is a serious complication especially when patients develop life-threatening neuroglycopenia with loss of consciousness and seizure. The avoidance of this adverse event may be achieved by strict dietary modification including a restriction on carbohydrates as well as foods with high glycemic index. Further research will provide more information on post-bariatric surgery hyperinsulinemic hypoglycemia pathophysiology and management.

Serum stearic acid/palmitic acid ratio as a potential predictor of diabetes remission after Roux-en-Y gastric bypass in obesity

Endogenous fatty acid metabolism that results in elongation and desaturation lipid products is thought to play a role in the development of type 2 diabetes mellitus (T2DM). In this study, we evaluated the potential of estimated elongase and desaturase activities for use as predictive markers for T2DM remission after Roux-en-Y gastric bypass (RYGB). The results of a targeted metabolomics approach from 2 independent studies were used to calculate 24 serum FA concentration ratios (product/precursor). Gene expression data from an open public data set was also analyzed. In a longitudinal study of 38 obese diabetic patients with RYGB, we found higher baseline stearic acid/palmitic acid (S/P) ratio. This ratio reflects an elovl6-encoded elongase enzyme activity that has been found to be associated with greater possibility for diabetes remission after RYGB [odds ratio, 2.16 (95% CI 1.10-4.26)], after adjustment for age, gender, body mass index, diabetes duration, glycosylated hemoglobin A1c, and fasting C-peptide. Our results were validated by examination of postsurgical elovl6 gene expression in morbidly obese patients. The association of S/P with the metabolic status of obese individuals was further validated in a cross-sectional cohort of 381 participants. In summary, higher baseline S/P was associated with greater probability of diabetes remission after RYGB and may serve as a diagnostic marker in preoperative patient assessment. - Zhao, L., Ni, Y., Yu, H., Zhang, P., Zhao, A., Bao, Y., Liu, J., Chen, T., Xie, G., Panee, J., Chen, W., Rajani, C., Wei, R., Su, M., Jia, W., Jia, W. Serum stearic acid/palmitic acid ratio as a potential predictor of diabetes remission after Roux-en-Y gastric bypass in obesity.

Weight Regain After Gastric Bypass: Influence of Gut Hormones

BACKGROUND

The Roux-en-Y gastric bypass (RYGB) is the gold standard bariatric operation. However, a major concern in late follow-up is the substantial weight regain. Understanding the role of gastrointestinal hormone secretion in this situation is relevant.

METHODS

The aim of the present study was to evaluate the influence of gastrointestinal hormones comparing postprandial secretion of ghrelin, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1), and leptin between patients with weight regain and those with favorable weight control. Twenty-four patients with follow-up from 27 to 59 months were divided into two groups according to sustained weight loss: group A (14 patients) had sustained weight losses, and group B (10 patients) had significant weight regain. Basal serum levels of ghrelin, GIP, GLP-1, and leptin after fasting and 30, 60, 90, and 120 min after a standard meal were measured.

RESULTS

There was no difference in the ghrelin secretion. There was a difference in the GIP secretion, with a higher percentage increase in 30 min in group A (330% × 192.2%; p = 0.01). There were also differences in the GLP-1 secretion, with higher increases in absolute (p = 0.03) and percentage values after 30 min in group A (124% × 46.5%; p = 0.01). There was also a difference between baseline leptin values, with higher levels in group B (p = 0.02).

CONCLUSIONS

The secretion of gut hormones in patients with weight regain after RYGB is different from that in patients with satisfactory weight outcome. After meal stimulation, reduced levels of GIP and GLP-1 may indicate the influence of gut hormones in the process of weight regain.

Essential bariatric emergencies for the acute care surgeon

Bariatric surgery is the most effective treatment for morbid obesity. Due to the high volume of weight loss procedures worldwide, the general surgeon will undoubtedly encounter bariatric patients in his or her practice. Liberal use of CT scans, upper endoscopy and barium swallow in this patient population is recommended. Some bariatric complications, such as marginal ulceration and dyspepsia, can be effectively treated non-operatively (e.g., proton pump inhibitors, dietary modification). Failure of conservative management is usually an indication for referral to a bariatric surgery specialist for operative re-intervention. More serious complications, such as perforated marginal ulcer, leak, or bowel obstruction, may require immediate surgical intervention. A high index of suspicion must be maintained for these complications despite "negative" radiographic studies, and diagnostic laparoscopy performed when symptoms fail to improve. Laparoscopic-assisted gastric band complications are usually approached with band deflation and referral to a bariatric surgeon. However, if acute slippage that results in gastric strangulation is suspected, the band should be removed immediately. This manuscript provides a high-level overview of all essential bariatric complications that may be encountered by the acute care surgeon.

Changes in insulin sensitivity and secretion after sleeve gastrectomy

Background

Sleeve gastrectomy is indicated for the treatment of obesity and related co-morbidity including diabetes. The dynamic changes in insulin secretion and sensitivity after sleeve gastrectomy are unknown.

Methods

Whole-body insulin sensitivity was measured by the euglycaemic hyperinsulinaemic clamp technique, and insulin secretion by C-peptide deconvolution after an oral glucose tolerance test (OGTT), before and 3, 6 and 12 months after sleeve gastrectomy in morbidly obese subjects. The time course of glucagon-like peptide (GLP) 1, as a marker of insulin secretion following OGTT, was also assessed.

Results

Ten patients were included in the study. Median (range) baseline insulin sensitivity (M-value) increased from 84·0 (20·2–131·4) mmol per kg per min at baseline to 122·8 (99·0–179·3) mmol per kg per min at 12 months after surgery (P = 0·015). Fasting insulin sensitivity, measured by homeostatic model assessment of insulin resistance, which represents a surrogate index of hepatic insulin resistance, decreased from 3·3 (1·9–5·5) to 0·7 (0·5–1·1) mg/dl·µunits/ml (P &lt; 0·001). Total insulin secretion, measured as incremental area under the curve (AUC), after OGTT decreased from 360·4 (347·9–548·0) to 190·1 (10·1–252·0) mmol/l·180 min at 12 months (P = 0·011). The AUC for GLP-1 increased from 258·5 (97·5–552·6) to 5531·8 (4143·0–7540·9) pmol/l·180 min at 12 months after sleeve gastrectomy (P &lt; 0·001). In multiple regression analysis, 51 per cent of the M-value variability was explained by GLP-1 secretion.

Conclusion

Sleeve gastrectomy improved insulin sensitivity and reduced insulin secretion within 6 months after surgery. Although there was a correlation between insulin sensitivity and bodyweight, the major driver of the improvement in insulin sensitivity was GLP-1 secretion.

Metabolic surgery for the treatment of type 2 diabetes in pancreas after kidney transplant candidates

Metabolic surgery for the treatment of type 2 diabetes mellitus (T2DM) in patients not morbidly obese (BMI <35) has been widely studied. Taking into account that ∼12% of pancreas transplants are performed in patients with T2DM, our goal was to evaluate the impact of metabolic surgery on the management of obese patients with T2DM on waiting lists for a pancreas transplant. We performed a Roux-en-Y gastrointestinal bypass in 5 patients with insulin-dependent T2DM who were candidates for pancreas after kidney transplant and with a BMI <35. Three patients became insulin independent by the end of the first year while the other 2 reduced their insulin requirements by 70%. Furthermore, all patients achieved improved control of lipid levels. We concluded that the surgery was effective in controlling blood glucose and lipid metabolism in these obese T2DM kidney transplant recipients. In this population, a pancreas transplant, along with its associated morbidity, may be avoided.

Bariatric and metabolic surgery: a shift in eligibility and success criteria

The obesity epidemic, combined with the lack of available and effective treatments for morbid obesity, is a scientific and public health priority. Worldwide, bariatric and metabolic surgeries are increasingly being performed to effectively aid weight loss in patients with severe obesity, as well as because of the favourable metabolic effects of the procedures. The positive effects of bariatric surgery, especially with respect to improvements in type 2 diabetes mellitus, have expanded the eligibility criteria for metabolic surgery to patients with diabetes mellitus and a BMI of 30-35 kg/m(2). However, the limitations of BMI, both in the diagnosis and follow-up of patients, need to be considered, particularly for determining the actual adiposity and fat distribution of the patients following weight loss. Understanding the characteristics shared by bariatric and metabolic surgeries, as well as their differential aspects and outcomes, is required to enhance patient benefits and operative achievements. For a holistic approach that focuses on the multifactorial effects of bariatric and metabolic surgery to be possible, a paradigm shift that goes beyond the pure semantics is needed. Such a shift could lead to profound clinical implications for eligibility criteria and the definition of success of the surgical approach.

Differences in Weight Loss and Gut Hormones: Rouen-Y Gastric Bypass and Sleeve Gastrectomy Surgery

Bariatric surgery is arguably the most effective therapy for weight loss, and Rouen-Y gastric bypass (RYGB) is considered the "gold-standard" procedure. However, sleeve gastrectomy (SG) surgery has become more prevalent in recent years and it is unclear if weight loss differences occur between these procedures. Herein, we discuss evidence from randomized clinical trials comparing the effectiveness of RYGB and SG on weight loss. Moreover, we highlight gut hormones (e.g., GLP-1, ghrelin, bile acids, etc.) as potentially important mechanisms that contribute to the durability of decreased appetite and opposed fat storage following RYGB and SG. Collectively, although a subtle (∼ 3-5 kg) weight loss difference may exist in favor of RYGB up to 3 years post-operation, it appears that RYGB and SG induce comparable weight loss and changes in gut physiology that parallel reduced disease risk. These findings are clinically relevant for optimizing treatment strategies that combat obesity-related diabetes and cardiovascular disease.

Laparoscopic Roux-en-Y Gastric Bypass versus Sleeve Gastrectomy for Obese Patients with Type 2 Diabetes: A Meta-analysis of Randomized Controlled Trials

We aimed to evaluate the efficacy and safety of laparoscopic Roux-en-Y gastric bypass versus sleeve gastrectomy for obese patients with Type 2 diabetes. We searched the Cochrane Library, PubMed, EMBASE, Google Scholar, and the Chinese Wan fang database up to October 2013. Randomized controlled trials regarding the efficacy and safety of laparoscopic gastric bypass versus sleeve gastrectomy for obese diabetic patients were included. Two review authors independently abstracted data and assessed the risk of bias. The mean difference and relative risk were estimated with 95 per cent confidence intervals. Four randomized controlled trials met inclusion criteria. There was no significant difference between gastric bypass and sleeve gastrectomy groups with regard to glycosylated hemoglobin (mean difference [MD], 0.41%; 95% confidence interval [CI], -0.09 to 0.91), fasting plasma glucose (standardized MD, 0.61 mg/mL; 95% CI, -0.10 to 1.32), the numbers of subjects using oral antihyperglycemic medications and insulin (relative rate [RR], 1.53; 95% CI, 0.45 to 5.24; RR, 1.44; 95% CI, 0.47 to 4.39, respectively), body weight (MD, 0.42 kg; 95% CI, -5.01 to 5.85), body mass index (MD, 0.85 kg/m2; 95% CI, 0.13 to 1.58), or waist circumference (MD, 1.59 cm; 95% CI, -3.02 to 6.19). However, cardiovascular risk was more significantly lessened in the gastric bypass group. Our meta-analysis demonstrated that compared with laparoscopic sleeve gastrectomy, Roux-en-Y gastric bypass offers equal efficacy for treatment of diabetes in obese patients but is associated with a significantly decreased cardiovascular risk.

Role of metabolic surgery in less obese or non-obese subjects with type 2 diabetes: influence over cardiovascular events

Bariatric surgery was initially developed as a tool for weight reduction only, but it is gaining increasing popularity because of its remarkable effect on glucose metabolism in morbidly obese and less obese patients. Recent publications have shown the good results of metabolic surgery, creating a new field of clinical research that is currently overflowing in the medical community with outstanding high-quality data. In morbidly obese population, there is compelling data on long term cardiovascular risk reduction and mortality, coming from longitudinal prospective studies and systematic reviews. Numbers range from 33 to 92% of decrease in fatal and nonfatal cardiovascular events . In low body mass index (BMI) diabetics, there is an increasing number of reported good outcomes after metabolic surgery with the aim to treat type 2 diabetes (T2DM). There is scarce information on cardiovascular outcomes in non-morbidly obese subjects, but the extraordinary glucose, lipid and blood pressure control in the published series are suggesting good long-term effects on cardiovascular risk profile and mortality. The papers review was comprehensive, including the available randomized controlled trials, long-term prospective series and systematic reviews.

Metabolic Surgery for Type 2 Diabetes in Patients with a BMI of <35 kg/m(2): A Surgeon's Perspective

Bariatric surgery was developed with the aim of weight reduction. Success was defined only by excess weight loss. Other indices of resolution of metabolic comorbidities were reported, but were mostly secondary. Several communications have reported that regardless of body mass index (BMI), complete or partial remission of type 2 diabetes mellitus (T2DM) is possible. These results mostly occur before weight loss, positioning metabolic surgery as a good tool for controlling the current T2DM epidemic. Medical treatment is evolving, but is expensive and not risk-free. Surgery aimed mainly at diseases such as diabetes and not weight loss are referred to as "metabolic surgery." Metabolic surgery has been proven to be safe and effective, and although more data are needed, it is unquestionable that a new discipline has been founded. Metabolic surgery can effectively treat T2DM in individuals with any BMI, including that below 35 kg/m(2).

The gut microbiota elicits a profound metabolic reorientation in the mouse jejunal mucosa during conventionalisation

OBJECTIVE

Proper interactions between the intestinal mucosa, gut microbiota and nutrient flow are required to establish homoeostasis of the host. Since the proximal part of the small intestine is the first region where these interactions occur, and since most of the nutrient absorption occurs in the jejunum, it is important to understand the dynamics of metabolic responses of the mucosa in this intestinal region.

DESIGN

Germ-free mice aged 8-10 weeks were conventionalised with faecal microbiota, and responses of the jejunal mucosa to bacterial colonisation were followed over a 30-day time course. Combined transcriptome, histology, (1)H NMR metabonomics and microbiota phylogenetic profiling analyses were used.

RESULTS

The jejunal mucosa showed a two-phase response to the colonising microbiota. The acute-phase response, which had already started 1 day after conventionalisation, involved repression of the cell cycle and parts of the basal metabolism. The secondary-phase response, which was consolidated during conventionalisation (days 4-30), was characterised by a metabolic shift from an oxidative energy supply to anabolic metabolism, as inferred from the tissue transcriptome and metabonome changes. Detailed transcriptome analysis identified tissue transcriptional signatures for the dynamic control of the metabolic reorientation in the jejunum. The molecular components identified in the response signatures have known roles in human metabolic disorders, including insulin sensitivity and type 2 diabetes mellitus.

CONCLUSION

This study elucidates the dynamic jejunal response to the microbiota and supports a prominent role for the jejunum in metabolic control, including glucose and energy homoeostasis. The molecular signatures of this process may help to find risk markers in the declining insulin sensitivity seen in human type 2 diabetes mellitus, for instance.

Hepatic and peripheral insulin sensitivity do not improve 2 weeks after bariatric surgery

OBJECTIVE

Bariatric surgery has rapid metabolic effects on glucose metabolism before the occurrence of clinically significant weight loss. This suggests an acute effect of the surgery itself, e.g., resulting from bypassing the nutrient flow from the proximal gastrointestinal tract. Rapid effects of Roux-en-Y gastric bypass surgery (RYGB) on glucose metabolism were defined.

DESIGN AND METHODS

Glucose metabolism and total triglyceride hydrolysis in the basal state and during a hyperinsulinemic euglycemic clamp using stable isotopes 2 weeks were studied before and after RYGB.

RESULTS

Eighteen pre-menopausal women scheduled for RYGB were included. 2 weeks after RYGB median weight loss was 7.8 kg. Basal insulin and glucose levels decreased after surgery. Endogenous glucose production (EGP) was lower after surgery. In addition, insulin levels were lower during the clamp after surgery, suggesting enhanced clearance. Hepatic and peripheral insulin sensitivity did not change. Free fatty acid (FFA) levels increased after surgery both in the basal state and during the first step of the clamp. Total triglyceride hydrolysis did not change in the basal state and tended to be higher during hyperinsulinemia.

CONCLUSIONS

Within 2 weeks, RYGB reduces basal EGP as well as insulin and glucose levels without an acute beneficial effect on hepatic or peripheral insulin sensitivity. The latter may be explained by higher rates of lipolysis and exposure to FFA induced by the hypocaloric state.

Restoration of euglycemia after duodenal bypass surgery is reliant on central and peripheral inputs in Zucker fa/fa rats

Gastrointestinal bypass surgeries that result in rerouting and subsequent exclusion of nutrients from the duodenum appear to rapidly alleviate hyperglycemia and hyperinsulinemia independent of weight loss. While the mechanism(s) responsible for normalization of glucose homeostasis remains to be fully elucidated, this rapid normalization coupled with the well-known effects of vagal inputs into glucose homeostasis suggests a neurohormonally mediated mechanism. Our results show that duodenal bypass surgery on obese, insulin-resistant Zucker fa/fa rats restored insulin sensitivity in both liver and peripheral tissues independent of body weight. Restoration of normoglycemia was attributable to an enhancement in key insulin-signaling molecules, including insulin receptor substrate-2, and substrate metabolism through a multifaceted mechanism involving activation of AMP-activated protein kinase and downregulation of key regulatory genes involved in both lipid and glucose metabolism. Importantly, while central nervous system-derived vagal nerves were not essential for restoration of insulin sensitivity, rapid normalization in hepatic gluconeogenic capacity and basal hepatic glucose production required intact vagal innervation. Lastly, duodenal bypass surgery selectively altered the tissue concentration of intestinally derived glucoregulatory hormone peptides in a segment-specific manner. The present data highlight and support the significance of vagal inputs and intestinal hormone peptides toward normalization of glucose and lipid homeostasis after duodenal bypass surgery.

Biological effects of bariatric surgery on obesity-related comorbidities

The prevalence of obesity has increased so rapidly over the last few decades that it is now considered a global epidemic. Obesity, defined as a body mass index (BMI) of 30 or more, is associated with several comorbid conditions that decrease life expectancy and increase health care costs. Diet therapies have been reported to be ineffective in the long-term treatment of obesity, and guidelines for the surgical therapy of morbid obesity (BMI ≥ 40 or BMI ≥ 35 in the presence of substantial comorbidities) have since been established. Considering the number of bariatric surgical procedures has dramatically increased since these guidelines were established, we review the types of bariatric surgical procedures and their impact on diabetes, sleep apnea, dyslipidemia and hypertension - 4 major obesity-related comorbidities.

Tissue specificity in fasting glucose utilization in slightly obese diabetic patients submitted to bariatric surgery

OBJECTIVE

The present study was planned to investigate, by means of quantitative FDG-PET, how bariatric surgery (BS) modifies the metabolic pattern of the whole body and different tissues in slightly obese patients with type 2 diabetes mellitus (T2DM).

DESIGN AND METHODS

Before, 1 and 4 months after BS, 21 consecutive slightly obese T2DM patients underwent blood sampling to estimate plasma levels of glucose, insulin, glycosylated hemoglobin. At the same time points, these patients underwent a dynamic (18) F-FDG PET study of thorax and upper abdomen in fasting state and after washout of T2DM therapy. Gjedde-Patlak analysis was applied to estimate glucose uptake in the whole body and in different tissues (myocardium, skeletal back muscle, adipose tissue, and liver).

RESULTS

Surgical intervention quickly lowered levels of both insulin and glucose documenting an amelioration of glucose tolerance. Similarly, skeletal muscle and myocardial glucose uptake significantly increased soon after surgery (P < 0.001 and P < 0.01 at 1 month versus baseline, respectively) and remained substantially stable thereafter. By contrast, glucose uptake slightly decreased from its baseline values in the liver (P < 0.01 at 4 months) while no response could be documented over time in the adipose tissue.

CONCLUSIONS

These findings document that BS-induced modification of glucose homeostasis in slightly obese T2DM patients is mostly due to an increase in muscle glucose consumption. The surgically modified metabolic pattern of these patients might be of interest as a new model to investigate mechanism underlying insulin resistance.

Lifestyle modifications and surgical options in the treatment of patients with obesity and type 2 diabetes mellitus

This article reviews recent developments in the behavioral and surgical treatment of obesity and type 2 diabetes mellitus (T2DM). Randomized controlled trials of comprehensive lifestyle-modification programs, which include dietary interventions, physical activity, and behavioral therapy, have shown weight losses of 7% to 10% of initial body weight within 4 to 6 months after treatment. These programs also reduce the likelihood of developing T2DM by 58% for individuals with impaired glucose tolerance. Long-term maintenance of these improvements requires continued implementation of the program diet, physical activity, and self-regulatory behaviors. This can be successfully facilitated by continued patient-provider contact, which is frequently delivered by phone, mail, email, or online. However, these benefits may have less impact on those with extreme obesity or more significant health problems. For these individuals, bariatric surgery may be a more appropriate treatment. Bariatric surgical procedures induce mean weight losses of 15% to 30% of initial body weight (depending on the procedure) within 2 years after surgery, as well as a 45% to 95% rate of diabetes remission. Familiarity with these developments can help physicians and patients to determine which combinations of behavioral, medical, and surgical interventions are appropriate for the treatment of obesity and T2DM.

Comparison of Bariatric Surgical Procedures for Diabetes Remission: Efficacy and Mechanisms

Bariatric surgery induces a mean weight loss of 15-30% of initial body weight (depending on the procedure), as well as a 45-95% rate of diabetes remission. Procedures that induce greater weight loss are associated with higher rates of diabetes remission. Improvements in glucose homeostasis after bariatric surgery are likely mediated by a combination of caloric restriction (followed by weight loss) and the effects of altered gut anatomy on the secretion of glucoregulatory gut hormones.

Biliopancreatic diversion with duodenojejunal exclusion associated with truncal vagotomy: a new proposal for type 2 diabetes mellitus treatment

PURPOSE

To evaluate the effectiveness of the biliopancreatic diversion surgery with duodenojejunal exclusion in combination with truncal vagotomy in type 2 diabetes mellitus (T2DM) patients with overweight or class I or II obesity.

METHODS

The study included ten patients with T2DM and class I or II obesity or overweight who were subjected to biliopancreatic diversion with duodenojejunal exclusion in combination with truncal vagotomy. The blood glucose levels during the pre- and postoperative periods were compared using the Friedman test. The significance level adopted was 5%.

RESULTS

There were significant differences between preoperative and postoperative blood glucose levels at three months (p=0.01), six months (p=0.001) and 12 months (p=0.001). There was also a significant difference between one month postoperative blood glucose and six months postoperative blood glucose (p=0.01). Glycosylated hemoglobin levels decreased in 80% of patients, there was marked improvement in their lipid profiles, and the average BMI reduction was 7.0±1.5 kg/m² at 12 months after the surgery.

CONCLUSION

In patients with type 2 diabetes mellitus associated with class I/II obesity or overweight, performing biliopancreatic diversion with duodenojejunal exclusion in combination with truncal vagotomy resulted in glycemic control, reduction of excess weight, and improvement of lipid profile 12 months after the surgery.

Upregulation of plasma insulin-like growth factor binding protein 2 levels after biliopancreatic diversion in humans

The biliopancreatic diversion surgery with duodenal switch (BPD-DS) is a surgical procedure that not only induces significant weight loss, but also promotes remission of diabetes. However, the mechanism responsible for this insulin-potentiating effect (both on sensitivity and production) is not yet clearly understood. The insulin-like growth factor (IGF) binding protein 2 (IGFBP-2) is a 36 kDa circulating protein that has been recently suggested to modulate insulin sensitization and fat accumulation. In humans, a low-circulating concentration of IGFBP-2 has been associated with obesity and insulin resistance. We thus tested the hypothesis that BPD-DS would trigger an increase in IGFBP-2 levels. Plasma IGFBP-2 was quantified by enzyme-linked immunosorbent assay in 77 severely obese men and women before and up to 1 year after BPD-DS surgery. Baseline IGFBP-2 levels were 159 ± 17 ng/ml. Plasma IGFBP-2 levels increased significantly as soon as 24 h after BPD-DS surgery and were further augmented at both 6 months and 1 year after the surgery, reaching 748 ± 65 ng/ml. Changes in IGFBP-2 concentrations were significantly and negatively associated with blood glucose, insulin, triglycerides, and total cholesterol levels. The present findings suggest that the rise in IGFBP-2 levels is associated with the improvements in glucose and lipid metabolism in the short- and long-term after BPD-DS. The mechanisms for the augmentation in IGFBP-2 after BPD-DS and its contribution to insulin sensitization remain to be elucidated.

The preliminary clinical experience with laparoscopic duodenojejunal bypass for treatment of type 2 diabetes mellitus in non-morbidly obese patients: the 1-year result in a single institute

BACKGROUND

Although various bariatric surgeries are widely known for their effect of ameliorating type 2 diabetes mellitus (T2DM), there are only a few reports demonstrating the effect of duodenojejunal bypass on T2DM. The aim of this study was to evaluate and report the clinical effects of laparoscopic duodenojejunal bypass (LDJB) in non-morbidly obese patients with T2DM.

METHODS

Twelve non-morbidly obese patients with T2DM underwent LDJB. Changes in fasting blood glucose, body mass index glycosylated hemoglobin (HbA1c), and dose of antidiabetic medications were recorded prospectively during a 1-year period.

RESULTS

Reduction in HbA1c occurred 3 months after surgery and was maintained up to 1 year, and hyperglycemia was reversed within 1 month after surgery and remained controlled at 12 months. BMI decreased significantly 1 month after surgery and then remained steady through the year. Three patients (25.0 %) stopped antidiabetic medication, seven (58.3 %) patients maintained or decreased doses, and two (16.7 %) increased doses. Seven (58.3 %) patients had a decline in HbA1c.

CONCLUSION

LDJB demonstrated a glycemic control effect up to 1 year on T2DM in non-morbidly obese patients.

Alterações dos parâmetros clínicos e laboratoriais em pacientes obesos com diabetes melito tipo 2 submetidos à derivação gastrojejunal em y de Roux sem anel

OBJETIVOS: Verificar as alterações do peso e índice de massa corporal em pacientes obesos grau II e III com diabete melito tipo 2 nos períodos pré e pós-operatório e as alterações dos parâmetros laboratoriais de glicemia de jejum, glicemia pós-prandial, hemoglobina glicada, insulina nos períodos pré e pós-operatório. MÉTODOS: Realizou-se estudo prospectivo selecionando 40 pacientes com obesidade grau II e III, submetidos à derivação gastrojejunal em Y-de-Roux sem anel. Analisou-se no pré e pós-operatório de 60 dias o peso, índice de massa corporal, glicemia de jejum, glicemia pós-prandial, hemoglobina glicada e insulina. RESULTADOS: O peso médio pré-operatório foi de 107,3Kg diminuindo para 89,5Kg no pós-operatório. O índice de massa corporal médio inicial foi de 39,5Kg/m2 e 32,9Kg/m2 com 60 dias de pós-operatório. A glicemia de jejum no pré-operatório foi de 132 mg/dl e no pós-operatório diminuiu 40,4 mg/dl em média. A glicemia pós-prandial foi de 172 mg/dl no pré-operatório e 111,6 mg/dl no controle pós-operatório. A hemoglobina glicada inicial foi de 7% declinando para 5,7% no pós-operatório. A insulina pré-operatória foi 29,6 uIU/ml e a pós-operatória 13,9 uIU/ml. Todas as variáveis apresentaram significância estatística com p<0,001. CONCLUSÃO: Houve significante diminuição de peso e no índice de massa corporal entre os períodos pré e pós-operatórios e diminuição também significante dos parâmetros laboratoriais de glicemia de jejum, glicemia pós-prandial, hemoglobina glicada, insulina entre os mesmos períodos.

Gastroplastia como tratamento do diabete melito tipo 2

RACIONAL: O diabete melito tipo 2 está, com certa frequência, associado à obesidade mórbida e pode ser prevenido, melhorado e até mesmo revertido com as diversas modalidades de operações bariátricas. OBJETIVOS: Comparar as glicemias séricas pré e pós-operatórias dos pacientes submetidos à gastroplastia com as técnicas de Capella e sleeve gástrico. MÉTODO: Estudo descritivo e prospectivo com análises das glicemias séricas pré e pós-operatórias de pacientes submetidos à gastroplastia. RESULTADOS: Dos 83 pacientes analisados, 76 (91,5%) eram do sexo feminino. A idade variou de 21 a 64 anos, sendo 44 anos a idade média. Setenta e sete (92,7%) foram submetidos à gastroplastia (Capella) e seis (7,3%) à sleeve gástrico. A glicemia pré-operatória variou de 125 a 500 mg/dL caindo para a variação de 76 a 120 mg/dL no pós-operatório de três meses. Dos 77 pacientes que usavam tratamento medicamentoso para a diabete, 57 tomavam metformina de 850 a 3500 mg por dia, 18 glibenclamida de 5 a 10 mg por dia e 17 insulina. Após 3 meses da operação, 92,2% cessaram o uso de medicamentos para diabete e em 100% dos que permaneceram medicados houve redução de mais de 65% na dose do fármaco, sendo que nenhum permaneceu dependente de insulina no tratamento. CONCLUSÃO: A cirurgia bariátrica constitui-se em método eficaz para a melhora e até mesmo reversão do diabete melito tipo 2.

Surgical treatments for obesity

Bariatric surgery is currently the most effective and durable treatment option for extreme obesity. Restrictive procedures, such as AGB and SG, limit gastric capacity and, thus, food intake while leaving the gastrointestinal tract intact. Malabsorptive procedures, such as BPD, shorten the length of the intestine to decrease nutrient absorption. Combined procedures, such as RYGB, include restriction and gastrointestinal rearrangement. Procedures that bypass segments of the gut are associated with greater weight loss and greater improvements in comorbid conditions than is gastric banding. This may be due, in part, to the differential effects of gastrointestinal rearrangement on the secretion of orexigenic and anorexigenic gut peptides that regulate appetite, glucose homeostasis, and body weight. Bariatric surgery is generally associated with low rates of perioperative and postoperative morbidity and mortality, although rigorous comparative safety data are lacking. High-quality, long-term, randomized, controlled trials are needed to compare the efficacy, safety, and cost effectiveness of the various bariatric surgery procedures with each other, as well as with intensive nonsurgical weight loss interventions.

Resolution of diabetes mellitus by ileal transposition compared with biliopancreatic diversion in a nonobese animal model of type 2 diabetes

BACKGROUND

It has been demonstrated that biliopancreatic diversion (BPD) and ileal transposition (IT) effectively induce weight loss and long-term control of type 2 diabetes in morbidly obese individuals. It is unknown whether the control of diabetes is better after IT or after BPD. The objective of this study was to investigate the effects of IT and BPD on the control of diabetes in an animal model.

METHODS

We performed IT and BPD on 10- to 12-week-old Goto-Kakizaki rats with a spontaneous nonobese model of type 2 diabetes, and we performed a series of detection. The rats were observed for 24 weeks after surgery.

RESULTS

Animals who underwent IT and BPD demonstrated improved glucose tolerance, insulin sensitivity and the secretion of glucagon-like peptide-1 compared with the sham-operated animals. Furthermore, IT resulted in a shorter duration of surgery and better postoperative recovery than BPD.

CONCLUSION

This study provides strong evidence for the crucial role of the hindgut in the resolution of diabetes after duodenum-jejunum bypass or IT. We confirmed that IT was associated with better postoperative recovery than BPD and had a similar control of diabetes as BPD in nonobese animals with type 2 diabetes.

Antidiabetic effects of duodenojejunal bypass in an experimental model of diabetes induced by a high-fat diet

Background

Obese patients with type II diabetes who undergo bariatric surgery revert to normal blood glucose and insulin levels, and develop a dramatic increase in insulin sensitivity. However, the mechanisms involved are unknown. This study characterized pancreatic islet and duodenojejunal enteroendocrine cells in normal mice and those with diabetes induced by a high-fat diet (HFD) following duodenojejunal bypass (DJB).

Methods

C57BL/6J mice, fed for 8 weeks either a normal diet (n = 10) or a HFD (n = 10) resulting in a hyperglycaemic state, underwent DJB (connection of the distal end of the jejunum to the distal stomach and direction of biliopancreatic secretions to the distal jejunum). Metabolic and immunohistological analyses were carried out on the pancreas and gastrointestinal tract.

Results

A significant decrease in fasting blood glucose was observed in normal-DJB and HFD-DJB mice 1 week after the operation, with improved glucose tolerance at 4 weeks. There were no changes in pancreatic β-cell mass, but an increase in the ratio of α-cell to β-cell mass was observed in the DJB groups. Furthermore, the number of cells expressing Pdx-1, glucagon-like peptide 1, pancreatic polypeptide and synaptophysin was increased in the bypassed duodenum and/or gastrojejunum of the DJB groups.

Conclusion

Both normal and obese diabetic mice that underwent DJB displayed improved glucose tolerance and a reduction in fasting blood glucose, which mimicked findings in obese diabetic patients following bariatric surgery. The present data suggest that an increase in specific enteroendocrine cell populations may play a critical role in normalizing glucose homeostasis.

Bariatric surgery: results in obesity and effects on metabolic parameters

PURPOSE OF REVIEW

The use of bariatric surgery is increasing at an enormous rate in all countries but the indications for the operation on the basis of metabolic derangements are not clear as only one controlled randomized trial has been performed so far. Thus, it is not clear whether bariatric surgery should be performed on obese patients with long-standing type 2 diabetes or poorly controlled hypertension or hypertriglyceridemia. The mechanism for the immediate improvement in glucose tolerance after gastric bypass is not clear but is being actively investigated.

RECENT FINDINGS

Gastric bypass appears to enhance glucagon-like peptide-1 production and suppress glucose-dependent insulinotropic polypeptide production. It appears that patients with type 2 diabetes and a greater BMI gain more benefit from the operation.

SUMMARY

Bariatric surgery, particularly gastric bypass, has powerful and usually persistent effects on type 2 diabetes, dyslipidemia, and hypertension but randomized controlled trials with predefined metabolic entry criteria and planned comprehensive follow-up are required.

Nutritional assessment of bariatric surgery patients presenting for plastic surgery: a prospective analysis

BACKGROUND

Assessment of nutritional status in the growing postbariatric patient population remains controversial. Previous literature suggests that these patients have poor nutrition that may have adverse effects on surgical outcomes. The authors sought to determine the optimal method of nutritional assessment in postbariatric patients.

METHODS

One hundred patients presenting for body contouring after bariatric surgery were consecutively enrolled in an institutional review board-approved prospective study. A trained nutritionist assessed protein and calorie intake. All patients underwent baseline laboratory assessment.

RESULTS

Eighteen percent of subjects had less than the recommended daily protein intake. Hypoalbuminemia was observed in 13.8 percent of subjects, with hypoprealbuminemia in 6.5 percent. Nearly forty percent of all patients had evidence of iron deficiency, with vitamin B12 deficiency present in 14.5 percent. Ten percent of subjects (all women) were confirmed to have iron deficiency anemia. Impaired fasting glucose was seen in 6.2 percent of subjects, whereas 3.6 percent had hemoglobin A1c levels greater than 6.5. Increasing age (odds ratio, 1.07) and greater change in body mass index (odds ratio, 1.11) were predictors of low protein intake. Dumping syndrome led to 13.3 times increased odds of low albumin levels.

CONCLUSIONS

The results suggest that inadequate nutrition is common among postbariatric patients presenting for body contouring. The lack of correlation between methods of nutritional assessment supports the combination of multiple methods in determining overall nutritional status. The presence of dumping syndrome, a large change in body mass index, and advanced age may help to identify patients with an increased risk of nutritional deficiency.

Banda gástrica com desvio jejunoileal: nova opção técnica em cirurgia bariátrica

RACIONAL: Os procedimentos cirúrgicos para tratamento da obesidade morbida têm sido eficientes na resolução desta afecção a curto e longo prazo. Com exceção da banda gástrica ajustável todos estes procedimentos de alguma forma são capazes de induzir a liberação de hormônios intestinais em função do desvio intestinal e desta forma exercerem um efeito metabólico. OBJETIVO: Com a intenção de obter efeitos semelhantes às operações que promovem um desvio intestinal, com as vantagens de baixa morbidade e mortalidade da BGA, foi proposto novo procedimento técnico associando à banda gástrica ajustável a um desvio jejunoileal. MÉTODO: O procedimento cirúrgico totalmente conduzido por videolaparoscopia, consiste na aplicação inicial da banda gástrica e a seguir a realização de anastomose látero-lateral a 80 cm do ângulo duodenojejunal e 120 cm da válvula ileocecal. RESULTADOS: Foram operados 10 pacientes com esta técnica, seis mulheres e quatro homens com IMC médio de 40 kg/m². A perda média de excesso de peso nos seis primeiros meses foi de 51,56%. Em quatro pacientes diabéticos houve normalização dos níveis glicêmicos e suspensão do uso da medicação antidiabética. CONCLUSÃO: Adição de desvio jejunoileal látero-lateral à banda gástrica pode melhorar a perda de peso em pacientes portadores de obesidade mórbida e contribuir para o controle da diabete tipo II.

Bariatric surgery in patients with type 2 diabetes: benefits, risks, indications and perspectives

Obesity plays a key role in the pathophysiology of type 2 diabetes (T2DM), and weight loss is a major objective, although difficult to achieve with medical treatments. Bariatric surgery has proven its efficacy in obtaining marked and sustained weight loss, and is also associated with a significant improvement in glucose control and even diabetes remission. Roux-en-Y gastric bypass appears to be more effective in diabetic patients than the restrictive gastroplasty procedure. This may be explained not only by greater weight reduction, but also by specific hormonal changes. Indeed, increased levels of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) may lead to improved beta-cell function and insulin secretion as well as reduced insulin resistance associated with weight loss. The presence of T2DM in obese individuals is a further argument to propose bariatric surgery, and even more so when diabetes is difficult to manage by medical means and other weight-related complications may occur. Bariatric surgery is associated with a better cardiovascular prognosis and reduced mortality, even though acute and long-term complications are present. The observation that surgical rerouting of nutrients triggers changes in the release of incretin hormones that, in turn, ameliorate the diabetic state in the absence of weight loss has led to the recent development of innovative surgical procedures. Thus, bariatric surgery may be said to be progressing towards so-called 'metabolic surgery', which merits further evaluation in patients with T2DM within a multidisciplinary approach that involves both surgeons and endocrinologists.

Weight loss and incretin responsiveness improve glucose control independently after gastric bypass surgery

BACKGROUND

The aim of the present study was to determine the mechanisms underlying Type 2 diabetes remission after gastric bypass (GBP) surgery by characterizing the short- and long-term changes in hormonal determinants of blood glucose.

METHODS

Eleven morbidly obese women with diabetes were studied before and 1, 6, and 12 months after GBP; eight non-diabetic morbidly obese women were used as controls. The incretin effect was measured as the difference in insulin levels in response to oral glucose and to an isoglycemic intravenous challenge. Outcome measures were glucose, insulin, C-peptide, proinsulin, amylin, glucagon, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1) levels and the incretin effect on insulin secretion.

RESULTS

The decrease in fasting glucose (r = 0.724) and insulin (r = 0.576) was associated with weight loss up to 12 months after GBP. In contrast, the blunted incretin effect (calculated at 22%) that improved at 1 month remained unchanged with further weight loss at 6 (52%) and 12 (52%) months. The blunted incretin (GLP-1 and GIP) levels, early phase insulin secretion, and other parameters of β-cell function (amylin, proinsulin/insulin) followed the same pattern, with rapid improvement at 1 month that remained unchanged at 1 year.

CONCLUSIONS

The data suggest that weight loss and incretins may contribute independently to improved glucose levels in the first year after GBP surgery.