First-phase insulin secretion, insulin sensitivity, ghrelin, GLP-1, and PYY changes 72 h after sleeve gastrectomy in obese diabetic patients: the gastric hypothesis

Vertical sleeve gastrectomy improves glucose-insulin homeostasis by enhancing β-cell function and survival via FGF15/19

Vertical sleeve gastrectomy (VSG) restores glucose homeostasis in obese mice and humans. In addition, the increased fibroblast growth factor (FGF)15/19 circulating level postsurgery has been implicated in this effect. However, the impact of FGF15/19 on pancreatic islets remains unclear. Using a diet-induced obese mice model, we demonstrate that VSG attenuates insulin hypersecretion in isolated pancreatic islets, likely due to morphological alterations in the endocrine pancreas such as reduction in islet, β-cell, and α-cell mass. In addition, VSG relieves gene expression of endoplasmic reticulum (ER) stress and inflammation markers in islets from obese mice. Incubation of INS-1E β-cells with serum from obese mice induced dysfunction and cell death, whereas these conditions were not induced with serum from obese mice submitted to VSG, implicating the involvement of a humoral factor. Indeed, VSG increased FGF15 circulating levels in obese mice, as well as the expression of FGF receptor 1 (Fgfr1) and its coreceptor β-klotho (Klb), both in pancreatic islets from VSG mice and in INS-1E cells treated with the serum from these mice. Moreover, exposing INS-1E cells to an FGFR inhibitor abolished the effects of VSG serum on insulin secretion and cell death. Also, recombinant FGF19 prevents INS-1E cells from dysfunction and death induced by serum from obese mice. These findings indicate that the amelioration of glucose-insulin homeostasis promoted by VSG is mediated, at least in part, by FGF15/19. Therefore, approaches promoting FGF15/19 release or action may restore pancreatic islet function in obesity.NEW & NOTEWORTHY Vertical sleeve gastrectomy (VSG) decreases insulin secretion, endoplasmic reticulum (ER) stress, and inflammation in pancreatic islets from obese mice. In addition, VSG increased fibroblast growth factor (FGF)15 circulating levels in obese mice, as well as the expression of FGF receptor 1 (Fgfr1) and its coreceptor β-klotho (Klb), both in pancreatic islets from VSG mice and in INS-1E β-cells treated with the serum from these mice. Serum from operated mice protects INS-1E cells from dysfunction and apoptosis, which was mediated by FGF15/19.

Comparing bariatric surgery and medical therapy for obese adolescents with type 2 diabetes

BACKGROUND

Mounting evidence in recent years has demonstrated that the number of obese adolescents has continued to rise. Obese adolescents are more likely to be diagnosed with type 2 diabetes, which causes additional harm. This study aimed to compare the clinical outcomes of bariatric surgery and medical treatment.

METHODS

We conducted a multicenter, nonrandomized, retrospective study on 202 obese adolescents with type 2 diabetes who received surgery or medical treatment in three hospitals from 2017 to 2019. We analyzed the effects of surgery and medical treatment in terms of weight loss, glycemic control and the remission of type 2 diabetes. Propensity score matching was conducted to balance the confounding factors.

RESULTS

Among the 202 adolescents, 109 adolescents underwent surgery, and the remaining 93 adolescents received nonsurgical treatment. Both in the entire cohort and in the propensity-score matching cohort, the mean body mass index (BMI) and total weight in the surgery group notably decreased. Similarly, the effect of surgery on glycemic control (with respect to HBG, HbA1c, HOMA-IR) was superior to that of medical treatment. In the surgery group, the remission rate of diabetes was 76.1% in the entire cohort and 80.5% in the matched group, which was significantly higher than that in the control group (6.5% and 5.7%, respectively). In addition, LRYGB had better effects on weight loss and glycemic control than LSG.

CONCLUSION

Bariatric surgery is more effective in the control of weight loss and type 2 diabetes than medical treatment. The effects between different types of bariatric surgeries remain to be further investigated, and longer follow-up times are needed.

[Indications in Obesity Therapy - Surgeons First?]

Obesity is a growing problem worldwide. For the first time since 2010, more people have been overweight than underweight. In particular, obesity-associated diseases, above all type 2 diabetes mellitus, pose enormous challenges to the healthcare system. On July 3, 2020, the German Bundestag recognised obesity as a disease and initiated the development of a diseases management program (DMP), which is currently being drawn up. So far, the indication for treatment of obesity in Germany has been based on the S3 guideline "Surgery of obesity and metabolic diseases" of the DGAV from 2018 and the S3 guideline "Prevention and therapy of obesity" of the German Obesity Society e. V. from 2014. This article gives an overview of the currently available conservative, medical, endoscopic and surgical treatment methods for overweight and obesity in Germany and explains the indications. Against the background of the reorientation of obesity treatment as a part of the DMP and the forthcoming revisions of the guidelines, the previous indication should be discussed critically. The scientific findings of the last few years show that surgical treatment of obesity not only achieves the greatest weight loss in the long term, but also that obesity-associated diseases are then treated more effectively and overall mortality is reduced significantly more effectively than with conservative treatment.

Impact of sleeve gastrectomy on abnormalities in carbohydrate tolerance in obese adult

INTRODUCTION

Facing the repeated failures of the medical management of obesity, bariatric surgery offers a promising therapeutic option in terms of achieving weight loss and metabolic benefits.

AIM

To evaluate the impact of sleeve gastrectomy on the carbohydrate profile of a group of obese subjects.

METHODS

It is a prospective study including 40 obese patients (7 Men and 33 Women) who underwent sleeve gastrectomy between 2016 and 2018. Clinical and biological parameters were collected before the intervention, at six months and one year after. Insulin resistance was defined by a HOMA-IR index ≥2.4. Remission of diabetes was determined using the American Society for Metabolic and Bariatric Surgery's (ASMBS) criteria.

RESULTS

The mean patients' age was 34.65 ± 8.17 years. The mean body mass index (BMI) was 50.23 ± 8.3 kg/m². One year after sleeve gastrectomy, the frequency of insulin resistance, decreased from 89% to 4% (p<0.05). The evolution of carbohydrate tolerance abnormalities was marked by the diabetes and prediabetes remission in 75% and 100% of cases, respectively. The mean excess weight loss was 55.8% at 12 months.

CONCLUSION

These results have expanded our knowledge of the short-term sleeve gastrectomy's effectiveness on the carbohydrate profile of obese subjects. However, it would be interesting to check the durability of this metabolic benefit in the medium and long term.

Is there a role for upper gastrointestinal contrast study to predict the outcomes of sleeve gastrectomy? Lessons learnt from a prospective study

Context:

The importance of upper gastrointestinal (UGI) contrast study following sleeve gastrectomy (SG) is equivocal. It can, however, yield anatomical and functional details, the significance of which mostly remains unknown.

Settings and Design:

This prospective, single-center study included SG patients between January 2018 and January 2019.

Materials and Methods:

UGI contrast study was done on post-operative day 1. The findings of the study namely gastroesophageal junction (GEJ) holdup time, presence of fundus, gastroduodenal emptying (GDE) time, and sleeve shape were compared with weight loss, improvement of glycosylated hemoglobin (HbA1c) and gastroesophageal reflux disease (GERD) symptoms at 3, 6, and 12 months follow-up.

Results:

There were 138 patients with 100% follow-up. Radiological sleeve patterns observed were: tubular (62.3%), superior (16.0%), and inferior (21.7%) pouches. GEJ holdup time had no effect on percentage total weight loss (%TWL) (P = 0.09) or HbA1c improvement (P = 0.077). The absence of fundus led to greater %TWL at 6 months (P = 0.048). GDE time <15 s led to higher %TWL (P = 0.028) and lower HbA1c (P = 0.010) at 12 months. Antrum size <2 cm was associated with higher %TWL (P = 0.022) and lower HbA1c level (P = 0.047) at 12 months. Vomiting and regurgitation were common with tubular sleeves.

Conclusion:

UGI contrast study can predict weight loss, HbA1c improvement, and GERD symptoms. The absence of fundus, small antrum, and rapid GDE are associated with better weight loss. HbA1c improvement is better with small antrum and rapid GDE. Tubular sleeve predisposes to vomiting and regurgitation.

Temporal Effects of Sleeve Gastrectomy on Glucose-Insulin Homeostasis and Incretin Hormone Response at 1 and 6 Months

BACKGROUND

Bariatric surgery is an effective treatment for morbid obesity and glycaemic dysfunction.

OBJECTIVES

The aim of the work was to examine both the static and dynamic changes of glucose-insulin homeostasis and incretin hormone response following sleeve gastrectomy (SG) in a sample of 55 participants preoperatively and 1 month and 6 months postoperatively. The focus was on a sample of patients with impaired glucose tolerance and type 2 diabetes (T2D).

SETTING

Morriston Hospital, UK.

METHODS

Prospective study comprising of 55 participants with impaired glucose homeostasis and T2D undergoing SG (mean body mass index [BMI] 50.4 kg/m², mean glycated haemoglobin [A1C] 7.4%). Serial measurements of glucose, insulin, C-peptide, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic hormone (GIP) were performed during oral glucose tolerance testing preoperatively and 1 and 6 months postoperatively. Areas under the curve (AUC) were examined at 30, 60, and 120 min.

RESULTS

We observed significant improvements in measures of obesity, as well as static and dynamic measures of glucose, insulin, C-peptide and HOMA. Furthermore, significant increases in GLP-1 response as early as 6 months postoperatively were also seen.

CONCLUSIONS

To our knowledge, no study has examined the detailed dynamic changes in glucose and insulin homeostasis in this number of participants undergoing SG in relation to incretin hormones GIP and GLP-1. This current study supports the role of SG for the treatment of obesity-related glucose dysregulation.

Brain-gut-microbiome interactions in obesity and food addiction

Normal eating behaviour is coordinated by the tightly regulated balance between intestinal and extra-intestinal homeostatic and hedonic mechanisms. By contrast, food addiction is a complex, maladaptive eating behaviour that reflects alterations in brain-gut-microbiome (BGM) interactions and a shift of this balance towards hedonic mechanisms. Each component of the BGM axis has been implicated in the development of food addiction, with both brain to gut and gut to brain signalling playing a role. Early-life influences can prime the infant gut microbiome and brain for food addiction, which might be further reinforced by increased antibiotic usage and dietary patterns throughout adulthood. The ubiquitous availability and marketing of inexpensive, highly palatable and calorie-dense food can further shift this balance towards hedonic eating through both central (disruptions in dopaminergic signalling) and intestinal (vagal afferent function, metabolic endotoxaemia, systemic immune activation, changes to gut microbiome and metabolome) mechanisms. In this Review, we propose a systems biology model of BGM interactions, which incorporates published reports on food addiction, and provides novel insights into treatment targets aimed at each level of the BGM axis.

Effect of Sleeve Gastrectomy on Ghrelin, GLP-1, PYY, and GIP Gut Hormones: A Systematic Review and Meta-analysis

OBJECTIVE

To perform a structured systematic review and meta-analysis to evaluate changes in ghrelin, glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and gastric inhibitory peptide (GIP) gut hormone levels in patients after sleeve gastrectomy.

BACKGROUND

Despite sleeve gastrectomy becoming the most common surgical weight loss procedure, weight loss mechanisms remain less clear.

METHODS

Searches of PubMed, EMBASE, Web of Science, and Cochrane Library databases were performed through April 1, 2019, in accordance with PRISMA and MOOSE guidelines. Randomized controlled trials and prospective observational studies evaluating pre and post-procedure hormones fasting ghrelin, postprandial GLP-1, postprandial PYY, and fasting GIP levels were included. Hedge g with random-effects models were used to determine pooled effect size and corresponding 95% confidence intervals (CIs).

RESULTS

A total of 28 studies (n = 653; 29.56% male) were included. Mean age was 42.00 ± 5.48 years, with average follow-up of 11.70 ± 11.38 months. Pre-procedure body mass index (BMI) was 46.01 ± 4.07 kg/m with a postsleeve gastrectomy BMI of 34.07 ± 3.73 kg/m, representing total body weight loss of 25.13 ± 4.44% and excess weight loss of 57.48 ± 9.64% (P < 0.001). Ghrelin decreased (Hedge g -1.486, 95% CI -1.884 to -1.089, I = 91.95%), whereas GLP-1 and PYY increased post-procedure (Hedge g 1.095, 95% CI 0.509 to 1.642, I = 84.38%; and Hedge g 1.396, 95% CI 0.781 to 2.011, I = 84.02%, respectively). GIP did not significantly change (Hedge g -0.213, 95% CI -1.019 to 0.592, I = 79.65%).

CONCLUSIONS

Fasting ghrelin levels decreased, whereas postprandial GLP-1 and PYY increased after sleeve gastrectomy. Fasting GIP levels remained unchanged. Future studies are needed to assess the role of these gut hormones and relationship to weight loss and metabolic outcomes.

Metabolic and cardiovascular outcomes of bariatric surgery

PURPOSE OF REVIEW

Bariatric surgery is an effective therapy for morbid obesity that also improves weight-related metabolic parameters and reduces morbidity and mortality. The purpose of this review is to consolidate our current understanding of metabolic, macrovascular and microvascular benefits of bariatric surgery and to provide an update.

RECENT FINDINGS

Early resolution of insulin resistance and type 2 diabetes mellitus (T2DM) varies by type of bariatric surgery and appears to be mediated by changes in secretion of gut hormones, metabolism of bile acids, expression of glucose transporters and the gut microbiome. Dyslipidaemia, atherosclerosis, microvascular complications of obesity and diabetes, systemic and tissue-level inflammation show evidence of regression and hypertension improves significantly after bariatric surgery.

SUMMARY

Bariatric surgery leads to improvements in obesity-related metabolic comorbidities such as dyslipidaemia, HDL functionality, hypertension, T2DM, insulin resistance and inflammation. It slows the atherosclerotic process and reduces cardiovascular and all-cause mortality. Recent data have demonstrated regression of the microvascular complications of obesity and diabetes including the regeneration of small nerve fibres. The magnitude of change in short-term metabolic effects depends on the surgical procedure whilst longer term effects are related to the amount of sustained excess weight loss.

Oea Signaling Pathways and the Metabolic Benefits of Vertical Sleeve Gastrectomy

OBJECTIVE

The aim of this study was to determine whether downstream [peroxisome proliferator-activated-receptor alpha (PPARα) and the G-protein coupled receptor, GPR119] and upstream (a fatty acid translocase, CD36) signaling targets of N-oleoylethanolamide (OEA) were necessary for weight loss, metabolic improvements, and diet preference following vertical sleeve gastrectomy (VSG).

SUMMARY BACKGROUND DATA

OEA is an anorectic N-acylethanolamine produced from dietary fats within the intestinal lumen that can modulate lipid metabolism, insulin secretion, and energy expenditure by activating targets such as PPARα and GPR119.

METHODS

Diet-induced obese mice, including wild-type or whole body knockout (KO) of PPARα, GPR119, and CD36, were stratified to either VSG or sham surgery before body weight, body composition, diet preference, and glucose and lipid metabolic endpoints were assessed.

RESULTS

We found increased duodenal production of OEA and expression of both GPR119 and CD36 were upregulated in wild-type mice after VSG. However, weight loss and glucose tolerance were improved in response to VSG in PPARαKO, GPR119KO, and CD36KO mice. In fact, VSG corrected hepatic triglyceride dysregulation in CD36KO mice, and circulating triglyceride and cholesterol levels in PPARαKO mice. Lastly, we found PPARα-mediated signaling contributes to macronutrient preference independent of VSG, while removal of CD36 signaling blunts the VSG-induced shift toward carbohydrate preference.

CONCLUSIONS

In the search for more effective and less invasive therapies to help reverse the global acceleration of obesity and obesity-related disease OEA is a promising candidate; however, our data indicate that it is not an underlying mechanism of the effectiveness of VSG.

Gender-related metabolic outcomes of laparoscopic sleeve gastrectomy in 6-month follow-up

Introduction

Laparoscopic sleeve gastrectomy (LSG) is recently a leading method in surgical treatment of morbid obesity. The metabolic outcome of intervention may be a result of many factors such as age, gender, preoperative weight loss and dietary restrictions.

Aim

To evaluate gender-related differences in the results of LSG in 6-month follow-up.

Material and methods

The study included 101 patients who underwent LSG at the University Clinical Hospital of Bialystok. Patients were divided and analyzed in 2 groups: males (n = 48) and females (n = 53). The primary analysis included the influence of gender on postoperative weight loss calculated using the percentage of excess weight loss (%EWL) and excess BMI loss (%EBMIL). For secondary outcomes the levels of glucose, insulin, glycated hemoglobin, aspartate transaminase, alanine transaminase, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides and C-reactive protein were analyzed.

Results

A significant influence of patients’ gender was proved for both %EWL (p = 0.026) and %EBMIL (p = 0.001). Females had significantly higher %EWL in 6-month follow-up than males (p = 0.0034). The analysis also showed significantly higher %EBMIL for women at 3 and 6 months observation (p = 0.022 and p < 0.001 respectively).

Conclusions

Laparoscopic sleeve gastrectomy is an effective method of obesity treatment especially in terms of postoperative weight loss. Females seem to benefit more from the procedure when analyzing the parameters of body mass reduction. However, further research is needed to provide strong evidence of an association between gender and the results of LSG.

First-Phase Insulin and Amylin after Bariatric Surgery: A Prospective Randomized Trial on Patients with Insulin Resistance or Diabetes after Gastric Bypass or Sleeve Gastrectomy

BACKGROUND

Most patients with severe obesity show glucose intolerance. Early after sleeve gastrectomy (LSG) or gastric bypass (LRYGB), a marked amelioration in glycemic control occurs. The underlying mechanism is not yet clear.

OBJECTIVE

To determine whether the improvement in glycemic control on the level of endocrine pancreatic function is due to an increased first-phase insulin secretion comparing LRYGB to LSG.

SETTING

University of Basel Hospital and St. Clara Research Ltd., Basel, Switzerland.

METHODS

Sixteen morbidly obese patients with severe obesity and different degrees of insulin resistance were randomized to LSG or LRYGB, and islet cell functions were tested by intravenous glucose and intravenous arginine administration before and 4 weeks after surgery.

RESULTS

Fasting insulin and glucose levels and homeostasis model assessment insulin resistance were significantly lower in both groups after surgery compared to baseline, while no change was seen in fasting C-peptide, amylin, and glucagon. After intravenous glucose stimulation, no statistically significant pre- to postoperative change in area under the curve (AUC 0-60 min) was seen for insulin, glucagon, amylin, and C-peptide. No statistically significant pre- to postoperative change in incremental AUC for first-phase insulin release (AUC 0-10 min), second-phase insulin secretion (AUC 10-60 min), and insulin/glucose ratio could be shown in either group. Arginine-stimulated insulin and glucagon release showed no pre- to postoperative change.

CONCLUSION

Intravenous glucose and arginine administrations show no pre- to postoperative changes of insulin release, amylin, glucagon, or C-peptide concentrations, and no differences between LRYGB and LSG were found. The postoperative improvement in glycemic control is not caused by changes in endocrine pancreatic hormone secretion.

Remission of Type 2 Diabetes Mellitus after Bariatric Surgery: Fact or Fiction?

Although type 2 diabetes mellitus (T2DM) has been traditionally viewed as an intractable chronic medical condition, accumulating evidence points towards the notion that a complete remission of T2DM is feasible following a choice of medical and/or surgical interventions. This has been paralleled by increasing interest in the establishment of a universal definition for T2DM remission which, under given circumstances, could be considered equivalent to a “cure”. The efficacy of bariatric surgery in particular for achieving glycemic control has highlighted surgery as a candidate curative intervention for T2DM. Herein, available evidence regarding available surgical modalities and the mechanisms that drive metabolic amelioration after bariatric surgery are reviewed. Furthermore, reports from observational and randomized studies with regard to T2DM remission are reviewed, along with concepts relevant to the variety of definitions used for T2DM remission and other potential sources of discrepancy in success rates among different studies.

Single-centre, triple-blinded, randomised, 1-year, parallel-group, superiority study to compare the effects of Roux-en-Y gastric bypass and sleeve gastrectomy on remission of type 2 diabetes and β-cell function in subjects with morbid obesity: a protocol for the Obesity surgery in Tønsberg (Oseberg) study

INTRODUCTION

Bariatric surgery is increasingly recognised as an effective treatment option for subjects with type 2 diabetes and obesity; however, there is no conclusive evidence on the superiority of Roux-en-Y gastric bypass or sleeve gastrectomy. The Oseberg study was designed to compare the effects of gastric bypass and sleeve gastrectomy on remission of type 2 diabetes and β-cell function.

METHODS AND ANALYSIS

Single-centre, randomised, triple-blinded, two-armed superiority trial carried out at the Morbid Obesity Centre at Vestfold Hospital Trust in Norway. Eligible patients with type 2 diabetes and obesity were randomly allocated in a 1:1 ratio to either gastric bypass or sleeve gastrectomy. The primary outcome measures are (1) the proportion of participants with complete remission of type 2 diabetes (HbA1c≤6.0% in the absence of blood glucose-lowering pharmacologic therapy) and (2) β-cell function expressed by the disposition index (calculated using the frequently sampled intravenous glucose tolerance test with minimal model analysis) 1 year after surgery.

ETHICS AND DISSEMINATION

The protocol of the current study was reviewed and approved by the regional ethics committee on 12 September 2012 (ref: 2012/1427/REK sør-øst B). The results will be disseminated to academic and health professional audiences and the public via publications in international peer-reviewed journals and conferences. Participants will receive a summary of the main findings.

TRIAL REGISTRATION NUMBER

NCT01778738;Pre-results.

Sleeve Gastrectomy and Roux-en-Y Gastric Bypass Achieve Similar Early Improvements in Beta-cell Function in Obese Patients with Type 2 Diabetes

Bariatric surgery is a treatment option for obese patients with type 2 diabetes mellitus (T2DM). Although sleeve gastrectomy (SG) is growing in favor, some randomized trials show less weight loss and HbA1c improvement compared with Roux-en-Y gastric bypass (RYGB). The study objective was to compare changes in beta-cell function with similar weight loss after SG and RYGB in obese patients with T2DM. Subjects undergoing SG or RYGB were studied with an intravenous glucose tolerance test before surgery and at 5–12% weight loss post-surgery. The primary endpoint was change in the disposition index (DI). Baseline BMI, HbA1c, and diabetes-duration were similar between groups. Mean total weight loss percent was similar (8.4% ± 0.4, p = 0.22) after a period of 21.0 ± 1.7 days. Changes in fasting glucose, acute insulin secretion (AIR), and insulin sensitivity (Si) were similar between groups. Both groups showed increases from baseline to post-surgery in DI (20.2 to 163.3, p = 0.03 for SG; 31.2 to 232.9, p = 0.02 for RYGB) with no significant difference in the change in DI between groups (p = 0.53). Short-term improvements in beta-cell function using an IVGTT were similar between SG and RYGB. It remains unclear if longer-term outcomes are better after RYGB due to greater weight loss and/or other factors.

Early postoperative changes of sphingomyelins and ceramides after laparoscopic sleeve gastrectomy

Background

This study aimed to determine early postoperative changes of serum sphingomyelin (SM) and ceramide (CER) species following laparoscopic sleeve gastrectomy (LSG).

Methods

Twenty obese patients [mean body mass index (BMI) 45,64 ± 6,10 kg/m²] underwent LSG and normal weight control patients (mean BMI 31,51 ± 6,21 kg/m²) underwent laparoscopic cholecystectomy. Fasting blood samples were collected prior to surgery, at day 1 and day 30 after surgery. Circulating levels of C16-C24 SMs, C16-C24 CERs and sphingosine-1-phosphate (S1P) were determined by an optimized multiple reaction monitoring (MRM) method using ultra fast-liquid chromatography (UFLC) coupled with tandem mass spectrometry (MS/MS). Serum activity of neutral sphingomyelinase (N-SMase) was assayed by standard kit methods, and ceramide-1-phosphate (C1P) levels were determined by enzyme-linked immunosorbent assay (ELISA). Lipid profile, routine biochemical and hormone parameters were assayed by standard kit methods. Insulin sensitivity was evaluated using homeostatic model assessment for insulin resistance (HOMA IR).

Results

A significant decrease was observed in serum levels of very-long-chain C24 SM, very-long-chain C22-C24 CERs, HOMA-IR, N-SMase and C1P in LSG patients after postoperation day 1 and day 30 compared to preoperation levels. At 30 days postsurgery, BMI was reduced by 11%, fasting triglycerides were significantly decreased, and insulin sensitivity was increased compared to presurgery values. A significant positive correlation was found between HOMA-IR and serum levels of C22-C24 CERs in LSG patients.

Conclusion

We conclude that very long chain CERs may mediate improved insulin sensitivity after LSG.

Reoperative surgery for nonresponders and complicated sleeve gastrectomy operations in patients with severe obesity. An international expert panel consensus statement to define best practice guidelines

BACKGROUND

Laparoscopic sleeve gastrectomy (SG) has rapidly become the most commonly performed bariatric procedure in the United States as well as other countries, with approximately 120,000 procedures being performed annually in the United States. Reoperative interventions after SG have become more prevalent in the past few years since the initial development of SG as a primary operation. Given the expected rapid growth of these reinterventions, an expert consensus conference was held with some of the most experienced bariatric surgeons in the world to better understand, discuss, and provide consensus on the reasons, indications, contraindications, and surgical options for nonresponders and complicated SG operations.

OBJECTIVES

Provide consensus-based best practice guidelines regarding the performance of reinterventions after failed or complicated SG in patients with obesity, using expert opinion by organizing a consensus meeting of experts and evaluating the current literature.

SETTING

The meeting was held in Boca Raton, Florida on February 18, 2017.

METHODS

The panel of 32 expert bariatric surgeons representing 12 countries and major regions of the world and all 6 populated continents identified 54 questions for consensus. Questions encompassed patient selection, indications, contraindications, surgical technique, prevention and management of weight regain, and short- and long-term complications after SG. Responses were calculated and defined as achieving consensus (≥70% agreement) or no consensus (<70% agreement). The current available literature was extensively reviewed for each topic in question and proposed to the panel.

RESULTS

Full consensus was obtained for the essential aspects of indications and contraindications, surgical technique, management, and prevention of complications. Consensus was achieved for 35 of 54 key questions. Highlights include consensus recommendations regarding technique in reoperation, management of GERD and Barrett's esophagus after SG, and surgical options for poor initial weight loss. No consensus was reached on topics, such as management of chronic proximal fistula after SG.

CONCLUSIONS

This first international expert meeting provides 35 statements and recommendations for a clinical consensus guideline regarding standardization of indications, contraindications, surgical options, and surgical techniques when reoperating on patients who underwent a failed or complicated SG. To our knowledge, the present consensus report represents the first document that defines best practice guidelines for the performance of reinterventions after failed or complicated SG.

Obesity and type 2 diabetes: Also linked in therapeutic options

The prevalence of obesity has increased worldwide over the past decades. Obesity is associated with multiple comorbidities, such as type 2 diabetes, that generates a great impact on health and economy. Weight loss in these patients leads to glycemic control so it is a target to achieve. Lifestyle changes are not effective enough and recently other treatments have been developed such as bariatric/metabolic surgery, as well as drugs for type 2 diabetes and antiobesity drugs. The aim of this review is to compare the results in weight reduction and glycemic control of the different kinds of drugs with bariatric / metabolic surgery's results in type 2 diabetes.

Which is the correlation between carcinoid tumor and Laparoscopic Sleeve Gastrectomy? A case series and literature review

Introduction

Gastric Carcinoid Tumors (GCT) are very rare in general population, but some studies evidenced a higher incidence among bariatric surgery patients. Laparoscopic Sleeve Gastrectomy (LSG) is a widely accepted procedure for the surgical treatment of morbid obesity. LSG acts both in reducing food intake and interfering with hormonal balance in the gut-brain axis. In these patients, incidental GCT diagnosis can occur both during pre-bariatric surgery investigation and during post-operative follow-up.

Methods

We retrospectively analyzed the database of obesity patients submitted to LSG in two different centers to find out incidence of GCT in patients treated by surgery from May 2013 to March 2018.

Results

From the 560 obese consecutive patients underwent LSG, we recorded two cases of patients with GCT (0.36%): the case 1 was a patient who had a pre-operative diagnosis of GTC receiving a curative LSG which totally included the carcinoid in the resected portion; the case 2 was a patient that received a curative endoscopic resection 42 months after LSG.

Discussion

the predisposing factors that can correlate GCT with obesity and LSG and in particular the hormonal changes have been discussed. We illustrated our experience about the management of these tumors in obese patients.

Conclusion

there are neither certain data which evidence a correlation between obesity and GCT, nor data to support the hypothesis of a higher incidence of GCT after bariatric surgery. Based on our experience in obese patients the finding of GCT in the pre-operatory phase is not an absolute contraindication for bariatric surgery.

•

Recent observations showed a high incidence of Gastric Carcinoid Tumor (GCT) in candidate patients for bariatric surgery.

•

From a multicenter experience with Laparoscopic Sleeve Gastrectomy.

•

We retrospectively recorded two GCT cases in obese patients (the first found out during pre-operative investigations and the second one detected 52 months after surgery).

•

The possible correlations between obesity, LSG and GTC have been discussed.

Long-term Metabolic Effects of Laparoscopic Sleeve Gastrectomy

OBJECTIVE

Obesity is one of the major health challenges throughout the world. The association between obesity and diabetes is well established because 90% of patients with type 2 diabetes mellitus (T2DM) show excess body weight. The aim of the study was to evaluate the effect of laparoscopic sleeve gastrectomy (LSG) on morbid obesity and type 2 diabetes (T2DM) in the long-term follow-up.

METHODS

One hundred ninety-five obese patients, 78 with T2DM, were evaluated before and after LSG up to 10 years, to identify complete diabetes remission (FPG < 100 mg/dl, A1c < 6.0%), partial remission (FPG 100-125 mg/dl, A1c < 6.5%), or relapse.

RESULTS

Before surgery, body weight and BMI were 123 ± 21 kg and 44.6 ± 6.8 kg/m² respectively; at a mean follow-up of 7 years (range 4-10), body weight was 104.9 ± 18 kg and BMI 37 ± 6 kg/m². Minimum weight was reached after 2 years. T2DM remission was observed in 66, 57, and 52% at short (< 2 years), medium (2-5 years), and long-term (> 5 years) follow-up respectively. Furthermore, 45.2% maintained complete remission for at least 5 years and about 36% showed a persistent but improved diabetes. None of the patients cured from diabetes had a duration disease greater than 8 years and a glycemic control requiring insulin. The prevalence of hypertension and dyslipidemia significantly decreased from 49 to 35% and from 51 to 40% respectively.

CONCLUSIONS

LSG significantly improves body weight, diabetes, hypertension, and dyslipidemia in long-term follow-up.

Gastric Plication and Sleeve Gastrectomy in an Experimental Model of Obesity: New Insights into Weight Loss, Intake and Metabolic Results

AIM

Laparoscopic gastric plication (LGP) is a bariatric surgical technique based on the anatomical principles of laparoscopic sleeve gastrectomy (LSG), but its effects on the metabolic profile are still uncertain. The aim of our study is to compare the changes in weight, metabolic parameters and gastric histology following intervention by gastric plication (GP) and sleeve gastrectomy (SG) in an experimental model of obesity.

METHODS

To conduct the study, 32 8-week-old male Sprague-Dawley rats (Charles River®) were fattened by means of a cafeteria diet and randomly assigned to the following experimental groups: group 1: GP (n = 12); group 2: SG (n = 12) and group 3: sham (n = 8).

RESULTS

Unlike the SG group, the GP group attained the weight of the sham group at the end of the experiment (week 16). The GP group continued to eat more cafeteria diet than the SG group. In addition, the SG group achieved better glycaemic control than the GP group. Significantly higher plasma ghrelin levels were observed at week 16 in the GP group than in the SG group (2.29 ± 0.5 vs 1.07 ± 0.4, p < 0.05), which also occurred for the glucagon plasmatic levels (62.71 ± 36.2 vs 24.63 ± 9.3, p < 0.05).

CONCLUSIONS

GP is not as effective as SG and cannot be considered a metabolic surgery due to observed hormonal variations. The animals subjected to a GP continued to have a high appetite for the cafeteria diet unlike the animals submitted to an SG. Hormonal mechanisms possibly related to glucagon and ghrelin may be involved in this metabolic response.

Gastric mucosal devitalization is safe and effective in reducing body weight and visceral adiposity in a porcine model

BACKGROUND AND AIMS

The early improvement in metabolic profile after sleeve gastrectomy (SG) indicates that the significant benefits of metabolic surgery are gastric in origin. We have previously demonstrated that devitalization of the gastric mucosa (without a reduction in gastric volume) in metabolically disturbed obese rats results in an improvement of obesity and its associated comorbidities. The aims of this study were to assess the technical feasibility, efficacy, and safety of gastric mucosal devitalization (GMD) in a large animal (porcine) model.

METHODS

A 3-arm (GMD versus SG versus sham [SH]) prospective randomized controlled trial with an 8-week follow-up period was performed. The primary endpoint was relative weight loss. Secondary endpoints were absolute body weight, abdominal visceral adiposity, abdominal subcutaneous adiposity, organ lipid content, and serum ghrelin level.

RESULTS

GMD resulted in a significant relative weight loss of 36% over SH at 8 weeks (P < .05). There was no significant difference in relative weight loss between GMD and SG at 4 weeks; however, SG resulted in a 29% superior relative weight loss at 8 weeks (P < .05). With regard to visceral adiposity, there was a significant benefit of GMD over SH at 8 weeks. Despite differences in relative weight loss, there was no significant difference in visceral adiposity between SG and GMD at 8 weeks. Significant improvements in GMD over SH were noted with regard to skeletal and heart muscle lipid content. GMD pigs at 8 weeks demonstrated regeneration of the gastric mucosa without ulceration or significant scarring. Despite mucosal regeneration, the abundance of serum ghrelin was significantly lower in the GMD cohort compared with the SG and SH cohorts.

CONCLUSIONS

GMD was technically feasible and resulted in relative weight loss and an improvement in visceral adiposity. The benefits noted were out of proportion to what would be expected with weight loss alone.

The Effects of Sleeve Gastrectomy on Glucose Metabolism and Glucagon-Like Peptide 1 in Goto-Kakizaki Rats

PURPOSE

To investigate the effects of sleeve gastrectomy (SG) on glucose metabolism and changes in glucagon-like peptide 1 (GLP-1) in Goto-Kakizaki (GK) rats.

METHODS

GK rats were randomly assigned to one of three groups: SG, SG pair-fed plus sham surgery (PF-sham), and ad libitum-fed no surgery (control). Food intake, body weight, blood glucose, GLP-1 and insulin levels, and GLP-1 expression in the jejunum and ileum were compared.

RESULTS

The SG rats exhibited lower postoperative food intake, body weight, and fasting glucose than did the control rats (P < 0.05). SG significantly improved glucose and insulin tolerance (P < 0.05). Plasma GLP-1 levels were higher in SG rats than in control or PF-sham rats in the oral glucose tolerance test (OGTT) (P < 0.05). Blood glucose levels expressed as a percentage of baseline were higher in SG rats than in control rats after exendin (9-39) administration (P < 0.05). The levels of GLP-1 expression in the jejunum and ileum were higher in SG rats than in PF-sham and control rats (P < 0.05).

CONCLUSIONS

Improvement of glucose metabolism by SG was associated with increased GLP-1 secretion. SG contributes to an increase in plasma GLP-1 levels via increased GLP-1 expression in the mucosa of the jejunum and/or ileum.

Gastric mucosal devitalization reduces adiposity and improves lipid and glucose metabolism in obese rats

BACKGROUND AND AIMS

The gastric mucosa is an endocrine organ that regulates satiation pathways by expression of orexigenic and anorexigenic hormones. Vertical sleeve gastrectomy (VSG) excludes gastric mucosa and reduces gastric volume. Our study aimed to investigate the independent effects of altering gastric mucosa on obesity and its related comorbidities.

METHODS

Gastric mucosa devitalization (GMD) of 70% of the stomach was achieved by argon plasma coagulation in a high-fat diet rat model and was compared with VSG and sham surgery. In an 8-week follow-up study, we quantified body weight, visceral adiposity, insulin resistance index, cholesterol profiles, and free fatty acid profiles by enzyme-linked immunosorbent assay (ELISA). Following a 2-hour oral glucose tolerance test, the kinetics of ghrelin, glucagon-like peptide-1, peptide YY, and serum and liver bile acid levels were measured. Liver lipid content was quantified by ELISA.

RESULTS

GMD resulted in significant reductions in body weight, visceral and subcutaneous adipose tissue, and hepatic steatosis as well as an improvement in lipid metabolism. GMD resulted in significant reductions in food intake and intestinal malabsorption of free fatty acids, both contributing to improved body composition and metabolic profile. Mechanistically, GMD resulted in a significant reduction in serum palmitate levels as well as an increase in serum and liver bile acid levels, known to alter glucose and lipid metabolism. Similar changes were noted when VSG rats were compared with sham surgery rats.

CONCLUSIONS

Devitalization of gastric mucosa, independent of altering gastric volume, was able to reduce obesity-related comorbidities. The gastric mucosa may be a potential target for treating obesity and its associated comorbidities.

Different surgical approaches in laparoscopic sleeve gastrectomy and their influence on metabolic syndrome: A retrospective study

Obesity is a growing health, social, and economic issue and became an epidemic, according to recent report of World Health Organization.The only method with scientifically proved efficiency of body mass loss is a surgical treatment. Laparoscopic sleeve gastrectomy (LSG) is recently a leading method in metabolic surgery. There are no standards of operative technique for LSG so far. The influence of technique modification on metabolic effect has not been described clearly.The aim of this study was to evaluate metabolic effects in patients with morbid obesity who underwent various surgical approaches of LSG.The study included 120 patients who were randomly divided into 3 groups: Group I, where bougie size was 32 French (Fr), Group II-36 Fr and Group III-40 Fr. Each group was divided into 2 subgroups, based on the distance of resection beginning from the pylorus-2 or 6 cm. Statistical analysis of: body mass index (BMI), the Percentage of Excess Weight Loss (%EWL), the Percentage of Excess BMI Loss (%EBMIL), levels of glucose and insulin on an empty stomach, glycated hemoglobin (HbA1c), insulin resistance (Homeostatic Model Assessment of Insulin Resistance Index-HOMA-IR), aspartate transaminase (AST), alanine transaminase (ALT), total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG), and C-reactive protein (CRP) were under investigation.Statistically significant decrease in body mass, BMI, %EWL, %EBL, glucose, and insulin concentrations has been observed in all studied groups. It was the highest when the smallest calibration tube has been used (32 Fr). Similar results were observed in HOMA-IR and HbA1c levels. Statistically significant decrease of total cholesterol, LDL, and TG concentrations have been observed. Significant increase of HDL in every group has been also noted. Postoperative CRP values were the lowest when the smallest bougie was used.LSG is effective method of obesity treatment. Metabolic effects of LSG are the most noticeable when a small bougie size is used.

Resolution of type 2 diabetes after sleeve gastrectomy: a 2-step hypothesis

BACKGROUND

Weight loss (WL) and altered gut hormonal levels are involved in glucose homeostasis after laparoscopic sleeve gastrectomy (LSG).

OBJECTIVES

The aim of this study was to evaluate the time-related effects of WL, ghrelin, and glucacon-like peptide-1 (GLP-1) plasma concentrations on type 2 diabetes resolution after LSG.

SETTING

University hospital, Italy.

METHODS

Ninety-one patients who underwent LSG were investigated. Insulin secretion (insulinogenic index [IGI]), insulin resistance, plasma glucose level and percentage glycated hemoglobin using the oral glucose tolerance test were assessed before surgery, on postoperative day 3, and then at 6, 12, 24, and 36 months after LSG. At the same time points, WL, ghrelin, and GLP-1 levels were determined.

RESULTS

During follow-up, the resolution rate of type 2 diabetes was 9.4%, 42.3%, 71.8%, 81.2%, and 91.8%, respectively. Ghrelin plasma concentrations decreased significantly after LSG (271.5 ± 24.5 pg/mL versus 122.4 ± 23.4 pg/mL, P = .04). GLP-1 plasma concentrations increased significantly after LSG (1.7 ± 2.6 pg/mL versus 2.5 ± 3.4 pg/mL, P = .04). The percentage of excess weight loss and IGI presented a positive linear correlation (r) at all follow-up time points with a strong positive correlation at 12 and 24 months. A strong negative correlation between ghrelin and IGI was recorded during the first 3 days after LSG (r = -.9). GLP-1 and IGI presented a strong positive correlation at day 3 and 6 months (i.e., .8 and .8, respectively).

CONCLUSION

LSG may affect glucose homeostasis by 2 different time-related modes: a first step in which the hormonal changes play a predominant role in glucose homeostasis and a second step in which the percentage excess weight loss determines the metabolic results.

Bariatric Surgery and Hypertension

Obesity continues to increase in prevalence worldwide. Hypertension has long been associated with obesity, and weight loss continues to be a first-line therapy in the treatment of hypertension. Lifestyle modification and pharmacologic therapy, however, often meet with treatment failure. Bariatric surgery continues to be the most successful approach to sustained weight loss. This review focuses on the underlying physiologic mechanisms of obesity-hypertension, and the impact of bariatric surgery on the treatment of hypertension. Current available literature on the physiologic mechanisms of obesity-hypertension, and the major trials, meta-analyses and systematic reviews of the impact of bariatric surgery procedures on hypertension are reviewed. Evidence suggests significant improvement in obesity-hypertension in patients who undergo surgical weight-reduction procedures. Malabsorptive techniques such as the Roux-en-Y gastric bypass or surgical resection techniques such as laparoscopic sleeve gastrectomy appear to offer superior results in regards to hypertension control over restrictive techniques such as Gastric Banding. Though long-term control of hypertension following surgery remains a concern, available follow-up post-operative data of up to 10 years suggests a sustained, if lessened, effect on hypertension control over time.

Preventative Sleeve Gastrectomy Contributes to Maintaining β Cell Function in db/db Diabetic Mouse

BACKGROUND

We used the leptin-receptor (LPR)-deficient mice model (db/db), a spontaneous model of type 2 diabetes with early β cell dysfunction to determine whether a preventative sleeve gastrectomy (SG) is an effective technique for the treatment of β cell failure.

METHODS

The animals operated at an early stage of life, prior to metabolic alterations, were used to study the molecular mechanisms of β cell function improvement after a SG.

RESULTS

β cell function was significantly increased, and islet morphology remained normal, after the SG. The expression of Glut2, Pdx1, MafA, and Nkx6.1 were significantly increased after the SG. The expression of GLP-1 in the colonic tissue, as well as GLP-1R and PKC in islets, was significantly increased after the SG.

CONCLUSIONS

β cell dysfunction can be ameliorated by a preventative SG for db/db mice. Maintaining the GLP-1 pathway and key transcript factor (TF) activation contributes to the improvement of β cell function after a preventative SG.

Neuroendocrine regulation of energy balance: Implications on the development and surgical treatment of obesity

INTRODUCTION

Obesity, a serious public health problem, occurs mainly when food consumption exceeds energy expenditure. Therefore, energy balance depends on the regulation of the hunger-satiety mechanism, which involves interconnection of the central nervous system and peripheral signals from the adipose tissue, pancreas and gastrointestinal tract, generating responses in short-term food intake and long-term energy balance. Increased body fat alters the gut- and adipose-tissue-derived hormone signaling, which promotes modifications in appetite-regulating hormones, decreasing satiety and increasing hunger senses. With the failure of conventional weight loss interventions (dietary treatment, exercise, drugs and lifestyle modifications), bariatric surgeries are well-accepted tools for the treatment of severe obesity, with long-term and sustained weight loss. Bariatric surgeries may cause weight loss due to restriction/malabsorption of nutrients from the anatomical alteration of the gastrointestinal tract that decreases energy intake, but also by other physiological factors associated with better results of the surgical procedure.

OBJECTIVE

This review discusses the neuroendocrine regulation of energy balance, with description of the predominant hormones and peptides involved in the control of energy balance in obesity and all currently available bariatric surgeries.

CONCLUSIONS

According to the findings of our review, bariatric surgeries promote effective and sustained weight loss not only by reducing calorie intake, but also by precipitating changes in appetite control, satiation and satiety, and physiological changes in gut-, neuro- and adipose-tissue-derived hormone signaling.

Bariatric Surgery for Adolescents with Type 2 Diabetes: an Emerging Therapeutic Strategy

PURPOSE OF REVIEW

Type 2 diabetes (T2D) is a growing public health problem in youth, but conventional treatments are often insufficient to treat this disease and its comorbidities. We review evidence supporting an emerging role for bariatric surgery as a treatment for adolescent T2D.

RECENT FINDINGS

Paralleling what has been seen in adult patients, bariatric surgery dramatically improves glycemic control in patients with T2D. In fact, remission of T2D has been observed in as many as 95-100% of adolescents with diabetes after bariatric surgery, particularly vertical sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB) surgery. This striking outcome may be due to both weight-dependent- and weight-independent factors, and recent studies suggest that T2D-related comorbidities may also improve after surgery. Bariatric surgery including RYGB and VSG is a powerful therapeutic option for obese adolescents with T2D. Benefits must be weighed against risk for postoperative complications such as nutritional deficiencies, but earlier surgical intervention might lead to more complete metabolic remission in obese patients with T2D.

Is it necessary to perform full pathologic review of all gastric remnants following sleeve gastrectomy?

BACKGROUND

This study attempts to determine if enough pathological abnormalities in gastric remnants from sleeve gastrectomy exist to warrant full pathologic evaluation in all remnants.

METHODS

Data was collected on patients undergoing sleeve gastrectomy between 08/01/2011 and 06/30/2014. Significant abnormalities were classified as any pathology that might require follow-up or treatment beyond standard follow-up. Age, comorbidities, gender, and Helicobacter pylori titers were analyzed and compared with pathology specimens using 95% confidence intervals and Phi contingency coefficients.

RESULTS

Full pathologic evaluation was available for 351/387 patients (91.2%). No examples of malignancy or dysplasia were identified. Gastritis was the most common abnormality. There was a statistically significant association between preoperative H. pylori and significantly abnormal pathology (p = 0.003). Other comorbidities had no association.

CONCLUSIONS

These results suggest that full pathologic evaluation of the gastric remnant following sleeve gastrectomy is unnecessary, particularly when gross pathology is not noted at initial operation.

Control of Food Intake by Gastrointestinal Peptides: Mechanisms of Action and Possible Modulation in the Treatment of Obesity

This review focuses on the control of appetite by food intake-regulatory peptides secreted from the gastrointestinal tract, namely cholecystokinin, glucagon-like peptide 1, peptide YY, ghrelin, and the recently discovered nesfatin-1 via the gut-brain axis. Additionally, we describe the impact of external factors such as intake of different nutrients or stress on the secretion of gastrointestinal peptides. Finally, we highlight possible conservative—physical activity and pharmacotherapy—treatment strategies for obesity as well as surgical techniques such as deep brain stimulation and bariatric surgery also altering these peptidergic pathways.

Comparison of glucose homeostasis parameters between patients with high and low risk of diabetes at 6 weeks and 6 months after sleeve gastrectomy

BACKGROUND

The changes in glucose homeostasis after sleeve gastrectomy (SG) for patients with high (HRD) and low risk (LRD) of developing diabetes have not been investigated.

OBJECTIVE

To compare the glucose homeostasis parameters between patients with HRD and LRD after SG.

SETTING

University hospital in Greece.

METHODS

Thirteen patients were categorized as HRD (9 females, mean body mass index 46.3±1.6 kg/m²) and 10 as LRD (8 females, mean body mass index 45.4±1.7 kg/m²) based on a preoperative 2-hour oral glucose tolerance test (OGTT). OGTT was repeated 6 weeks and 6 months postoperatively. OGTT-derived indices of insulin secretion, insulin sensitivity, and β-cell function (oral disposition index [ODI]) were calculated.

RESULTS

Preoperatively, in the HRD group, fasting and postload glucose levels were higher and the ODIs were lower compared with those in the LRD group. Six weeks postoperatively, glucose levels and ODIs were not different between the 2 groups. However, 6 months postoperatively, the HRD group had demonstrated higher postload glucose levels and lower ODI (0-30) and ODI (0-120) compared with the LRD group. Six weeks postoperatively, insulin levels, early insulin secretion, and insulin resistance indices were decreased compared with preoperative levels only in the HRD group. Six months postoperatively, ODIs and insulin sensitivity indices improved in both groups compared with baseline.

CONCLUSION

Six months after SG, glucose levels and ODIs improved for both HRD and LRD patients; however, postprandial glucose levels and ODI (0-30) and ODI (0-120) in HRD patients did not return to LRD levels. Moreover, during the first 6 postoperative weeks, the changes in glucose homeostasis parameters compared with preoperative levels were different for HRD and LRD patients.

Effect of Resected Gastric Volume on Ghrelin and GLP-1 Plasma Levels: a Prospective Study

BACKGROUND

The correlation between resected gastric volume (RGV) and neuro-humoral changes (ghrelin and GLP-1) after laparoscopic sleeve gastrectomy (LSG) and their effects on type 2 diabetes mellitus (T2DM) has been evaluated.

MATERIALS

Ninety-eight patients were divided in two groups: RGV <1200 mL (group A: 53 pts) and RGV >1200 mL (group B: 45 pts). Insulin secretion (insulin area under the curve (AUC)), insulinogenic index (IGI) and insulin-resistance (homeostasis model assessment, HOMA_IR) were assessed before and after surgery (at the 3rd day and 6, 12 and 24 months after LSG) using the oral glucose tolerance test (OGTT). At the same time, ghrelin and GLP-1 levels were determined.

RESULTS

A significant difference in T2DM resolution rate was observed after 6, 12 and 24 months in favour of RGV >1200 mL. Group B performed better than group A at the 3rd day and at the 6th, 12th and 24th months with regard to AUC, IGI and HOMA_IR. In both groups, OGTT resulted in decreased ghrelin values and a significant increase in GLP-1 values for group B at the 3rd day and at the 6th and 12th months with no difference at the 24th month.

CONCLUSION

Ghrelin and GLP-1 changes play a role in the regulation of glucose metabolism during the 1st year after LSG. RGV influences ghrelin and GLP-1 plasma levels after LSG, with a significant improvement in the T2DM control.

Bariatric surgery and type 2 diabetes: are there weight loss-independent therapeutic effects of upper gastrointestinal bypass?

Type 2 diabetes (T2D) is a major worldwide public health concern. Despite a large armamentarium of T2D medications, a large proportion of patients fail to achieve recommended treatment goals for glycemic control. Weight loss has profound beneficial effects on the metabolic abnormalities involved in the pathogenesis of T2D. Accordingly, bariatric surgery, which is the most effective available weight loss therapy, is also the most effective therapy for treating patients with T2D. Surgical procedures that bypass the upper gastrointestinal (UGI) tract are particularly effective in achieving partial and even complete remission of T2D, suggesting that UGI bypass has weight loss-independent effects on glycemic control. Although a number of hypotheses (e.g. a role for multiorgan insulin sensitivity, β-cell function, incretin response, the gut microbiome, bile acid metabolism, intestinal glucose metabolism and browning of adipose tissue) have been proposed to explain the potential unique effects of UGI tract bypass surgery, none has yet been adequately evaluated to determine therapeutic importance in patients with T2D. Here, we review the efficacy of UGI bypass surgery in treating T2D and the mechanisms that have been proposed to explain its potential weight loss-independent therapeutic effects.

Insulin Resistance, Microbiota, and Fat Distribution Changes by a New Model of Vertical Sleeve Gastrectomy in Obese Rats

Metabolic surgery improves insulin resistance and type 2 diabetes possibly because of weight loss. We performed a novel sleeve gastrectomy in rats that resects ∼80% of the glandular portion, leaving the forestomach almost intact (glandular gastrectomy [GG]) and compared subsequent metabolic remodeling with a sham operation. GG did not affect body weight, at least after 10 weeks; improved hepatic and peripheral insulin sensitivity likely through increased Akt, glycogen synthase kinase 3, and AMPK phosphorylation; and reduced ectopic fat deposition and hepatic glycogen overaccumulation. Body adipose tissue was redistributed, with reduction of intraabdominal fat. We found a reduction of circulating ghrelin levels, increased GLP-1 plasma concentration, and remodeling of gut microbiome diversity characterized by a lower relative abundance of Ruminococcus and a higher relative abundance of Lactobacillus and Collinsella These data suggest that at least in rat, the glandular stomach plays a central role in the improvement of insulin resistance, even if obesity persists. GG provides a new model of the metabolically healthy obese phenotype.

The effect of sleeve gastrectomy on GLP-1 secretion and gastric emptying: a prospective study

BACKGROUND

Rapid gastric emptying has been proposed to justify the increase in glucagon-like polypeptide-1 (GLP-1) after laparoscopic sleeve gastrectomy (LSG).

OBJECTIVES

To assess gastric emptying changes after LSG and their relationship with GLP-1 secretion.

SETTING

San Salvatore Hospital general surgery unit, University of L'Aquila, Italy.

METHODS

52 patients underwent gastric emptying scintigraphy for liquid and solid foods, before and 3 months after LSG. Twenty-six patients were in the liquid group (L group) and the remaining in the solid group (S group). We evaluated the half time of gastric emptying (T_1/2) and percentage of gastric retention (%GR) at 15, 30, and 60 minutes for liquids and at 30, 60, 90, and 120 minutes for solids. GLP-1 plasma concentrations were measured in each group before and after LSG and related to %GR. Statistical analysis was performed by Χ2 test and Pearson correlation(r).

RESULTS

After surgery, T_1/2 was significantly accelerated: 15.2±13 min and 33.5±18 min in the L group and S group, respectively (P<.05). In both groups, GLP-1 plasma concentrations were increased at each blood sampling time: 2.91±2.9 pg/mL, 3.06±3.1 pg/mL and 3.21±2.6 pg/mL at 15, 30, and 60 minutes, respectively, (P<.05) for L group and 2.72±1.5 pg/mL, 2.89±2.1 pg/mL, 2.93±1.8 pg/mL, and 2.95±1.9 pg/mL at 30, 60, 90, and 120 minutes, respectively, (P< .05) for the S group. After LSG, GLP-1 and %GR presented a negative linear correlation (r) at each blood sampling time in both groups.

CONCLUSION

The rapid gastric emptying 3 months after LSG upregulates the production of GLP-1 in the distal bowel. Further studies are needed to confirm these findings.

The incretin effect in healthy individuals and those with type 2 diabetes: physiology, pathophysiology, and response to therapeutic interventions

The incretin effect describes the phenomenon whereby oral glucose elicits higher insulin secretory responses than does intravenous glucose, despite inducing similar levels of glycaemia, in healthy individuals. This effect, which is uniformly defective in patients with type 2 diabetes, is mediated by the gut-derived incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). The importance of the incretin effect for the maintenance of glucose homoeostasis is clearly established, and incretin-based therapies are among the most promising new therapies for type 2 diabetes. However, despite the effectiveness of these therapies in many patients, the idea that they restore the incretin effect is a common misconception. In type 2 diabetes, the endocrine pancreas remains responsive to GLP-1 but is no longer responsive to GIP, which is the most likely reason for a reduced or absent incretin effect. Incretin-based drugs, including GLP-1 receptor agonists and dipeptidyl peptidase 4 (DPP-4) inhibitors, stimulate GLP-1 receptors and thus augment insulin secretion in response to both oral and intravenous glucose stimulation, thereby abolishing any potential difference in the responses to these stimuli. These drugs therefore do not restore the defective incretin effect in patients. By contrast, some bariatric surgical procedures enhance GLP-1 responses and also restore the incretin effect in obese individuals with type 2 diabetes. Thus, not all biological actions elicited by the stimulation of GLP-1 receptors lead to quantitative changes to the incretin effect.

Changes of insulin sensitivity and secretion after bariatric/metabolic surgery

Type 2 diabetes (T2D) is classically characterized by failure of pancreatic β-cell function and insulin secretion to compensate for a prevailing level of insulin resistance, typically associated with visceral obesity. Although this is usually a chronic, progressive disease in which delay of end-organ complications is the primary therapeutic goal for medical and behavioral approaches, several types of bariatric surgery, especially those that include intestinal bypass components, exert powerful antidiabetes effects to yield remission of T2D in most cases. It has become increasingly clear that in addition to the known benefits of acute caloric restriction and chronic weight loss to ameliorate T2D, bariatric/metabolic operations also engage a variety of weight-independent mechanisms to improve glucose homeostasis, enhancing insulin sensitivity and secretion to varying degrees depending on the specific operation. In this paper, we review the effects of Roux-en-Y gastric bypass, biliopancreatic diversion, and vertical sleeve gastrectomy on the primary determinants of glucose homeostasis: insulin sensitivity, insulin secretion, and, to the lesser extent that it is known, insulin-independent glucose disposal. A full understanding of these effects should help optimize surgical and device-based designs to provide maximal antidiabetes impact, and it holds the promise to identify targets for possible novel diabetes pharmacotherapeutics. These insights also contribute to the conceptual rationale for use of bariatric operations as "metabolic surgery," employed primarily to treat T2D, including among patients not obese enough to qualify for surgery based on traditional criteria related to high body mass index.

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.

Laparoscopic sleeve gastrectomy: More than a restrictive bariatric surgery procedure?

Sleeve gastrectomy (SG) is a restrictive bariatric surgery technique that was first used as part of restrictive horizontal gastrectomy in the original Scopinaro type biliopancreatic diversion. Its good results as a single technique have led to a rise in its use, and it is currently the second most performed technique worldwide. SG achieves clearly better results than other restrictive techniques and is comparable in some aspects to the Roux-en-Y gastric bypass, the current gold standard in bariatric surgery. These benefits have been associated with different pathophysiologic mechanisms unrelated to weight loss such as increased gastric emptying and intestinal transit, and activation of hormonal mechanisms such as increased GLP-1 hormone and decreased ghrelin. The aim of this review was to highlight the salient aspects of SG regarding its historical evolution, pathophysiologic mechanisms, main results, clinical applications and perioperative complications.

A meta-analysis of 2-year effect after surgery: laparoscopic Roux-en-Y gastric bypass versus laparoscopic sleeve gastrectomy for morbid obesity and diabetes mellitus

Literature search was performed for bariatric surgery from inception to September 2013, in which the effects of laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG) on body mass index (BMI), percentage of excess weight loss (EWL%), and diabetes mellitus (DM) were compared 2 years post-surgery. A total of 9,756 cases of bariatric surgery from 16 studies were analyzed. Patients receiving LRYGB had significantly lower BMI and higher EWL% compared with those receiving LSG (BMI mean difference (MD) = -1.38, 95% confidence interval (CI) = -1.72 to -1.03; EWL% MD = 5.06, 95% CI = 0.24 to 9.89). Improvement rate of DM was of no difference between the two types of bariatric surgeries (RR = 1.05, 95% CI = 0.90 to 1.23). LRYGB had better long-term effect on body weight, while both LRYGB and LSG showed similar effects on DM.

Relationship between gastric pouch and weight loss after laparoscopic sleeve gastrectomy

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is considered safe and effective even as conversion procedure after primary bariatric operations. The correlation between gastric pouch volumes and patients weight loss remains unclear.

METHODS

To assess a correlation between the gastric remnant size and the weight loss, we reviewed 49 consecutive barium swallow UGS performed at our institute from August 2012 through May 2014 in LSG patients with symptoms and/or unsatisfactory weight loss. The anteroposterior (AP), laterolateral (LL) and vertical (CC) diameters of the gastric pouch were measured to calculate the volume by the formula of the ellipsoid (AP × LL × CC × 0.5). Patients were divided in two groups: group 1 without gastric pouch (n = 36) and group 2 with gastric pouch (n = 13). Correlation between pouch volume and weight loss data was calculated with t Student's and Fisher tests to compare the percent excess body mass index (BMI) and percent excess body mass loss (EBL) between two groups, and P < 0.05 was considered statistically significant.

RESULTS

The mean percent EBL was 26.54 ± 11.02 and 27.12 ± 12.35 kg/m(2) in groups with and without pouch, respectively. The mean volume of the pouch after LSG was 17.13 ± 21.56 mm(3). Pouch volume, when present, was not significantly correlated to weight loss (P = 0.88 95% CI, CL 19.88-33.20 group 2; CL 22.94-31.30 group 1).

CONCLUSIONS

No statistical correlation was found between the volume of the gastric pouch and weight loss (percent EBL) after LSG in symptomatic or with unsatisfactory weight loss patients.

Gut Microbiome and Obesity: A Plausible Explanation for Obesity

Obesity is a multifactorial disorder that results in excessive accumulation of adipose tissue. Although obesity is caused by alterations in the energy consumption/expenditure balance, the factors promoting this disequilibrium are incompletely understood. The rapid development of new technologies and analysis strategies to decode the gut microbiota composition and metabolic pathways has opened a door into the complexity of the guest-host interactions between the gut microbiota and its human host in health and in disease. Pivotal studies have demonstrated that manipulation of the gut microbiota and its metabolic pathways can affect host's adiposity and metabolism. These observations have paved the way for further assessment of the mechanisms underlying these changes. In this review we summarize the current evidence for possible mechanisms underlying gut microbiota induced obesity. The review addresses some well-known effects of the gut microbiota on energy harvesting and changes in metabolic machinery, on metabolic and immune interactions and on possible changes in brain function and behavior. Although there is limited understanding on the symbiotic relationship between us and our gut microbiome, and how disturbances of this relationship affects our health, there is compelling evidence for an important role of the gut microbiota in the development and perpetuation of obesity.