Portuguese observational cross-sectional clinical imaging study protocol to investigate central dopaminergic mechanisms of successful weight loss through bariatric surgery.

INTRODUCTION: Bariatric surgery (BS) is the treatment of choice for refractory obesity. Although weight loss (WL) reduces the prevalence of obesity-related comorbidities, not all patients maintain it. It has been suggested that central mechanisms involving dopamine receptors may play a role in successful WL. This protocol describes an observational cross-sectional study to test if the binding of central dopamine receptors is similar in individuals who responded successfully to BS and age- and gender-matched normal-weight healthy individuals (controls). As secondary goals, the protocol will investigate if this binding correlates with key parameters such as age, hormonal status, anthropometric metrics and neurobehavioural scores. Finally, as exploratory goals, we will include a cohort of individuals with obesity before and after BS to explore whether obesity and type of BS (sleeve gastrectomy and Roux-en-Y gastric bypass) yield distinct binding values and track central dopaminergic changes resulting from BS. METHODS AND ANALYSIS: To address the major research question of this observational study, positron emission tomography (PET) with [11C]raclopride will be used to map brain dopamine type 2 and 3 receptors (D2/3R) non-displaceable binding potential (BPND) of individuals who have successfully responded to BS. Mean regional D2/3R BPND values will be compared with control individuals by two one-sided test approaches. The sample size (23 per group) was estimated to demonstrate the equivalence between two independent group means. In addition, these binding values will be correlated with key parameters to address secondary goals. Finally, for exploratory analysis, these values will be compared within the same individuals (before and after BS) and between individuals with obesity and controls and types of BS. ETHICS AND DISSEMINATION: The project and informed consent received ethical approval from the Faculty of Medicine and the Coimbra University Hospital ethics committees. Results will be disseminated in international peer-reviewed journals and conferences.

Surgery is associated with better long-term outcomes than pharmacological treatment for obesity: a systematic review and meta-analysis.

Obesity is a highly prevalent disease with numerous complications. Both intensive medical treatment with the use of pharmacological drugs and bariatric surgery are current options. The objective of this meta-analysis was to compare, in the long-term, intensive medical treatment and surgery based on twelve parameters related to weight loss, cardiovascular and endocrine changes. A review of the literature was conducted in accordance with the PRISMA guidelines (PROSPERO: CRD42021265637). The literature screening was done from inception to October 2023 through PubMed, EMBASE and Web of Science databases. We included randomized clinical trials that had separate groups for medical treatment and bariatric surgery as an intervention for obesity. The risk of bias was assessed through RoB2. A meta-analysis was performed with measures of heterogeneity and publication bias. Subgroup analysis for each surgery type was performed. Data is presented as forest-plots. Reviewers independently identified 6719 articles and 6 papers with a total 427 patients were included. All studies were randomized controlled trials, three had a follow up of 5 years and two had a follow up of 10 years. Both groups demonstrated statistical significance for most parameters studied. Surgery was superior for weight loss (- 22.05 kg [- 28.86; - 15.23), total cholesterol (- 0.88 [- 1.59; - 0.17]), triglycerides (- 0.70 [- 0.82; - 0.59]), HDL (0.12 [0.02; 0.23]), systolic pressure (- 4.49 [- 7.65; - 1.33]), diastolic pressure (- 2.28 [- 4.25; - 0.31]), Hb glycated (- 0.97 [- 1.31; - 0.62]), HOMA IR (- 2.94; [- 3.52; - 2.35]) and cardiovascular risk (- 0.08; [- 0.10; - 0.05]). Patient in the surgical treatment group had better long term outcomes when compared to the non-surgical group for most clinical parameters.

Evaluating Night-Eating Syndrome in bariatric surgery patients: A cross-sectional study.

BACKGROUND: Night-Eating Syndrome (NES) is a complex eating disorder that has gained recognition in the context of bariatric surgery. However, its prevalence and associated factors in this specific patient population remain understudied, particularly in the Saudi Arabian context. METHODS: This cross-sectional study was conducted at King Abdulaziz University Hospital in Jeddah, Saudi Arabia, from June to November 2022. Adult patients who had undergone bariatric surgery with a postoperative follow-up of 6 months were included. NES was assessed using the Night Eating Questionnaire (NEQ). RESULTS: A total of 154 patients were enrolled in the study, with a mean age of 38.8 ± 11.4 years. The mean BMI before surgery was 44.8 ± 8.2 kg/m2, which reduced to 28.9 ± 5.8 kg/m2 post-surgery. Of these, 52 patients (33.8%) met the criteria for NES based on NEQ scores. The prevalence of NES was significantly higher among female patients, with 35 out of 83 females (42.2%) compared to 17 out of 71 males (23.9%) experiencing NES. While NES was not significantly associated with age, nationality, diet adherence, BMI, or surgery type, chronic diseases-particularly diabetes-emerged as significant risk factors for NES in post-bariatric surgery patients. CONCLUSION: NES is a prevalent concern among post-bariatric surgery patients, with distinct associations with gender and chronic diseases, particularly diabetes. This study provides valuable insights into NES prevalence and its risk factors in the Saudi Arabian context, highlighting the importance of addressing eating disorders within the framework of bariatric surgery care.

Laparoscopic assisted versus ultrasound guided transversus abdominis plane block in laparoscopic bariatric surgery: a randomized controlled trial.

BACKGROUND: Transversus abdominis plane block (TAPB) guided by laparoscopy and ultrasound showed promise in enhancing the multimodal analgesic approach following several abdominal procedures. This study aimed to compare the efficacy and safety between Laparoscopic (LAP) TAP block (LTAP) and ultrasound-guided TAP block (UTAP) block in patients undergoing LAP bariatric surgery. PATIENTS AND METHODS: This non-inferiority randomized controlled single-blind study was conducted on 120 patients with obesity scheduled for LAP bariatric surgeries. Patients were allocated into two equal groups: LTAP and UTAP, administered with 20 mL of 0.25% bupivacaine on each side. RESULTS: There was no statistically significant difference in the total morphine consumption, Visual Analogue Scale (VAS) score at all times of measurements, and time to the first rescue analgesia (p > .05) between both groups. The duration of anesthesia and duration of block performance were significantly shorter in the LTAP group than in the UTAP group (p < .001). Both groups had comparable post-operative heart rate, mean arterial pressure, adverse effects, and patient satisfaction. CONCLUSIONS: In LAP bariatric surgery, the analgesic effect of LTAP is non-inferior to UTAP, as evidenced by comparable time to first rescue analgesia and total morphine consumption with similar safety blocking through the low incidence of post-operative complications and patient satisfaction. TRIAL REGISTRATION: The study was registered in Pan African Clinical Trials Registry (PACTR) (ID: PACTR202206871825386) on June 29, 2022.

Metabolic Bariatric Surgery Across the IFSO Chapters: Key Insights on the Baseline Patient Demographics, Procedure Types, and Mortality from the Eighth IFSO Global Registry Report.

INTRODUCTION: The International Federation for Surgery for Obesity and Metabolic Disorders (IFSO) Global Registry aims to provide descriptive data about the caseload and penetrance of surgery for metabolic disease and obesity in member countries. The data presented in this report represent the key findings of the eighth report of the IFSO Global Registry. METHODS: All existing Metabolic and Bariatric Surgery (MBS) registries known to IFSO were invited to contribute to the eighth report. Aggregated data was provided by each MBS registry to the team at the Australia and New Zealand Bariatric Surgery Registry (ANZBSR) and was securely stored on a Redcap™ database housed at Monash University, Melbourne, Australia. Data was checked for completeness and analyzed by the IFSO Global Registry Committee. Prior to the finalization of the report, all graphs were circulated to contributors and to the global registry committee of IFSO to ensure data accuracy. RESULTS: Data was received from 24 national and 2 regional registries, providing information on 502,150 procedures. The most performed primary MBS procedure was sleeve gastrectomy, whereas the most performed revisional MBS procedure was Roux-en-Y gastric bypass. Asian countries reported people with lower BMI undergoing MBS along with higher rates of diabetes. Mortality was a rare event. CONCLUSION: Registries enable meaningful comparisons between countries on the demographics, characteristics, operation types and approaches, and trends in MBS procedures. Reported outcomes can be seen as flags of potential issues or relationships that could be studied in more detail in specific research studies.

Novel subtype of obesity influencing the outcomes of sleeve gastrectomy: Familial aggregation of obesity.

BACKGROUND: Differences in the preoperative characteristics and weight loss outcomes after sleeve gastrectomy (SG) between patients with familial aggregation of obesity (FAO) and patients with sporadic obesity (SO) have not been elucidated. AIM: To explore the impact of SG on weight loss and the alleviation of obesity-related comorbidities in individuals with FAO. METHODS: A total of 193 patients with obesity who underwent SG were selected. Patients with FAO/SO were matched 1:1 by propensity score matching and were categorized into 4 groups based on the number of first-degree relatives with obesity (1SO vs 1FAO, 2SO vs 2FAO). The baseline characteristics, weight loss outcomes, prevalence of obesity-related comorbidities and incidence of major surgery-related complications were compared between groups. RESULTS: We defined FAO as the presence of two or more first-degree relatives with obesity. Patients with FAO did not initially show significant differences in baseline data, short-term postoperative weight loss, or obesity-related comorbidities when compared to patients with SO preoperatively. However, distinctions between the two groups became evident at the two-year mark, with statistically significant differences in both percentage of total weight loss (P = 0.006) and percentage of excess weight loss (P < 0.001). The FAO group exhibited weaker remission of type 2 diabetes mellitus (T2DM) (P = 0.031), hyperlipidemia (P = 0.012), and non-alcoholic fatty liver disease (NAFLD) (P = 0.003) as well as a lower incidence of acid reflux (P = 0.038). CONCLUSION: FAO patients is associated with decreased mid-to-long-term weight loss outcomes; the alleviation of T2DM, hyperlipidemia and NAFLD; and decreased incidence of acid reflux postoperatively.

Routine Upper Gastrointestinal Series Post-bariatric Surgery: Predictors, Usage, and Utility.

OBJECTIVE: To investigate usage and utility of routine upper gastrointestinal (UGI) series in the immediate post-operative period to evaluate for leak and other complications. METHODS: Single institution IRB-approved retrospective review of patients who underwent bariatric procedure between 01/08 and 12/12 with at least 6-month follow-up. RESULTS: Out of 135 patients (23%) who underwent routine UGI imaging, 32% of patients were post-gastric bypass (127) versus 4% of sleeve gastrectomy (8). In patients post-gastric bypass, 22 were found with delayed contrast passage, 3 possible obstruction, 4 possible leak, and only 1 definite leak. In patients post-sleeve gastrectomy, 2 had delayed passage of contrast without evidence of a leak. No leak was identified in 443 patients (77%) who did not undergo imaging. The sensitivity and specificity of UGI series for the detection of leak in gastric bypass patients were 100% and 97%, respectively, and the positive and negative predictive values were 20% and 100%, respectively. On univariate and multivariate analysis, sleeve gastrectomy patients (OR 0.4 sleeve vs bypass; P < 0.01) and male patients (OR 0.4 M vs F; P 0.02) were less likely to undergo routine UGI series (OR 0.4 M vs F; P 0.02). CONCLUSION: Routine UGI series may be of limited value for the detection of anastomotic leaks after gastric bypass or sleeve gastrectomy and patients should undergo routine imaging based on clinical parameters. Gastric bypass procedure and female gender were factors increasing the likelihood of routine post-operative UGI. Further larger scale analysis of this important topic is warranted.

Predictors of Chronic Pain 6 Months and 1 Year After Bariatric Surgery.

BACKGROUND: Obesity and chronic pain (CP) represent serious, interrelated global public health concerns that have a profound impact on individuals and society. Bariatric surgery is increasing in popularity and has been proven safe and efficacious, providing long-term weight loss and improvements in many obesity-related co-morbidities. A decrease in CP is often a motivation for bariatric surgery. The purpose of this study was to investigate the changes in CP postoperatively and to examine the relationship between psychosocial measures and pain. METHODS: A total of 155 adult bariatric surgery patients were recruited and completed self-report measures for CP severity and interference, neuropathic pain, anxiety, depression, emotion regulation and perceived social support at three timepoints preoperative and 6 and 12 months postoperative. RESULTS: Pain significantly decreased between preoperative and postoperative timepoints, and preoperative pain was the most significant predictor of postoperative pain. Preoperative CP was correlated with anxiety (p < 0.05) and depression (p < 0.01) at 6 months postoperatively and perceived social support (p < 0.01) at 1 year postoperatively. However, regression analyses with psychological variables were not significant. CONCLUSION: CP decreases after bariatric surgery, but further research with larger sample sizes is needed to establish whether psychosocial characteristics impact this outcome.

Bariatric Surgery in Patients with Achondroplasia, a Feasibility Study of Two Case Studies.

BACKGROUND: Achondroplasia is a common skeletal dysplasia with a high prevalence of obesity in adulthood. Bariatric surgery has been shown to be effective in treating obesity and related comorbidities, but its feasibility and effectiveness in patients with achondroplasia have not been clearly established. OBJECTIVES: The objective of this study was to evaluate the feasibility and effectiveness of bariatric surgery in patients with achondroplasia. SETTING: This study was performed in France, and bariatric surgeons from the Société Française et Francophone de Chirurgie de l'Obésité et des Maladies Métaboliques (French Francophone Society of Surgery for Obesity or Metabolic Diseases) were asked to participate. METHODS: Two adult women with confirmed achondroplasia and a high BMI were selected for laparoscopic sleeve gastrectomy. Preoperative data were collected, including demographic information, comorbidities, and follow-up at 1, 3, and 6 months and 1 year after surgery. Complications were monitored and recorded. RESULTS: Both patients had good excess weight loss outcomes, with an average excess weight loss of 60.5% 1 year after surgery. One patient had a follow-up of 3 years and an excess weight loss of 44%. The surgery was well-tolerated, and no major complications were observed. CONCLUSIONS: Bariatric surgery is feasible and effective in patients with achondroplasia, with good outcomes for excess weight loss and related comorbidities. These findings suggest that bariatric surgery should be considered a treatment option for patients with achondroplasia and obesity.

A Dutch Survey on Medication Adjustments after Metabolic and Bariatric Surgery: Experiences of Bariatric Surgeons, Internists, Pharmacists, and General Practitioners.

BACKGROUND: As metabolic and bariatric surgery (MBS) can alter the pharmacokinetics of drugs, post-bariatric surgery patients may require medication adjustments and monitoring. To improve pharmacotherapy in these patients, we aimed to understand the beliefs, attitudes, knowledge, and concerns of healthcare professionals who treat these patients. METHODS: A survey by means of an online questionnaire was divided into six sections. It was sent to bariatric surgeons, internists, pharmacists, and general practitioners in the Netherlands. RESULTS: Out of 229 returned surveys, 222 were included. Virtually all respondents (98%) expected MBS to influence the effect of medication. Both reduced efficacy (23%) and more adverse events or medication-related complications (21%) were recognized. Two-thirds of the respondents felt competent to prescribe or to provide advice regarding medication in post-bariatric surgery patients. Most of the respondents (95%) believed that other healthcare professionals should be aware of the contraindication "bariatric surgery". Of the respondents, 37% indicated that they were not aware of the medication advice incorporated in the electronic health record systems. Almost half of the respondents (48%) indicated that they documented changes in drug effects. Most respondents answered that these ought to be registered in the pharmacovigilance database or national registry. CONCLUSIONS: The majority of prescribers and pharmacists believe that patients will receive better pharmacotherapy if healthcare professionals take MBS into account. However, not all prescribers think they are competent to act adequately. To improve this, information on changed drug effects after MBS should be more widely shared among healthcare professionals via resources that are easily accessible.

Medium and Long-Term Weight Loss After Revisional Bariatric Surgery: A Systematic Review and Meta-Analysis.

Despite the current increase in revisional bariatric surgery (RBS), data on the sustainability of weight loss remain unclear. A systematic review and meta-analysis were performed to assess weight loss outcomes in adult patients undergoing RBS with follow-up > 2 years. Twenty-eight observational studies (n = 2213 patients) were included. The %TWL was 27.2 (95%CI = 23.7 to 30.6), and there was a drop in BMI of 10.2 kg/m2 (95%CI = - 11.6 to - 8.7). The %EWL was 54.8 (95%CI = 47.2 to 62.4) but with a high risk of publication bias (Egger's test = 0.003). The overall quality of evidence was very low. Our data reinforce that current evidence on RBS is mainly based on low-quality observational studies, and further higher-quality studies are needed to support evidence-based practice.

Bariatric Surgery Improves Serum CD40L Levels as a Predictor of Cardiovascular Risk: Systematic Review and Meta-analysis.

CD40 and its ligand have been recently implicated in the pathogenesis of cardiovascular disease (CVD). This meta-analysis examined the effect of bariatric surgery in reducing circulating CD40L levels. A systematic review was performed using Embase, Google Scholar, PubMed, Scopus, and Web of Science. The meta-analysis was provided by Comprehensive Meta-Analysis (CMA) V4 software. The overall effect size was detected by a random-effects meta-analysis and the leave-one-out approach. Random-effects meta-analysis of 7 studies including 191 subjects showed a significant reduction in CD40L after bariatric surgery (standardized mean difference (SMD), - 0.531; 95% CI, - 0.981, - 0.082; p = 0.021; I2, 87.00). Circulating levels of CD40L are decreased after bariatric surgery which may represent a mechanism for improvement of metabolic profile.

Impact of bariatric surgery on ovarian reserve markers and its correlation with nutritional parameters and adipokines.

Introduction: A reduction in anti-müllerian hormone (AMH) levels at short-term after bariatric surgery (BS) has been previously described. However, an assessment of ovarian reserve at longer-follow up, and a comprehensive evaluation of the potentially implicated factors has not been reported. Design: Prospective cohort study. Materials and methods: Twenty women aged 18-40 years with BMI 43.95 kg/m2 undergoing BS were studied at baseline (BS0), and at 1 month (BS1), 4 months (BS2), 12 months (BS3), and 24-36 months (BS4) after the surgery. Anthropometrics, reproductive hormones (AMH, FSH, LH, estradiol, testosterone, SHBG, androstenedione), metabolic parameters (adiponectin, leptin, ghrelin, insulin), and nutritional blood parameters (markers of nutritional status, vitamins, and minerals) were obtained at each study time point. Antral follicular count (AFC) was assessed by ultrasonography at BS0, BS3, and BS4. Mixed models were used for analysis of longitudinal data. Results: The mean AMH level was 3.88 ng/mL at BS0, decreased at BS3 (mean= 2.59 ng/mL; p=0.009), and remained stable between BS3 and BS4 (mean= 2.96 ng/mL; p=0.409). We also observed a non-significant decrease in AFC at BS3 (mean=26.14 at BS0, mean 16.81 at BS3; p=0.088) that remained stable at BS4 (mean= 17.86; p=0.731). Mixed models analysis showed: (a) a decrease in 10 kg of body weight was associated with an average decrease of 0.357 ng/mL in AMH (p=0.014); (b) a decrease in 1 BMI point was associated with an average decrease of 0.109 ng/mL in AMH (p=0.005); (c) an increase in 1 µg/mL of adiponectin was associated with an average decrease of 0.091 ng/ml in AMH (p=0.041) Significant positive correlations were found between the AMH levels after BS and plasma concentrations of testosterone, free androgen index, insulin and HOMA index. No significant correlations were detected between AMH levels and nutritional parameters. Conclusions: Our results were in line with previous observations, showing that AMH levels decreased significantly at 12 months after bariatric surgery, in parallel with a non-significant reduction in AFC. Both ovarian reserve markers showed a later stabilization up to the end of the study. Of note, postoperative AMH levels were positively correlated with key androgen and insulin resistance-related parameters.

Exploring Bariatric Surgery's Impact on Weight Loss and Diabetes: Sodium and Glucose Receptor Modulation.

Sodium-glucose cotransporters (SGLT) and glucose transporters (GLUT) have been shown to influence diabetes management by modulating glucose uptake by the intestine. Therefore, alterations in gastrointestinal anatomy during bariatric surgery can change SGLT and GLUT receptor activity. These changes offer an additional mechanism for weight loss and may explain the differential impact of the various bariatric surgical procedures. This review examines the current literature on SGLT and GLUT receptors and their effects on weight loss through genetic studies, pharmacologic inhibition, and how SGLT/GLUT receptors impact surgical physiologic modulation. A better understanding of Type I sodium-glucose cotransport receptors (SGLT-1), GLUT-2, and GLUT-5 could provide insight for improved procedures and allow us to determine the best method to tailor operations to a patient's individual needs.

Role of bariatric surgery in reducing periprosthetic joint infections in total knee arthroplasty. A systematic review and meta-analysis.

BACKGROUND: Obesity represents an epidemic of rising numbers worldwide year after year. In the Orthopedic field, obesity is one of the major causes leading to osteoarthritis needing Total Joint Arthroplasty (TJA). Still, contextually, it represents one of the most significant risk factors for joint replacement complications and failures. So, bariatric Surgery (BS) is becoming a valuable option for weight control and mitigating obesity-related risk factors. This review of the literature and meta-analysis aims to evaluate periprosthetic joint infections (PJI) and surgical site infections (SSI) rates in patients who underwent TKA after BS compared to obese patients without BS. METHODS: Systematic review was performed according to Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines up to October 2023. We included longitudinal studies comparing obese patients who underwent total knee arthroplasty after bariatric surgery (study group) and obese patients who underwent TKA (control group). The surgical site infection and Periprosthetic joint infection rate were compared among groups using a meta-analytical approach. RESULTS: The online database and references investigation identified one hundred and twenty-five studies. PJI rate differed significantly among groups, (z = -21.8928, p < 0.0001), with a lower risk in the BS group (z = -10.3114, p < 0.0001), for SSI, instead, not statistically significance were recorded (z = -0.6784, p = 0.4975). CONCLUSIONS: The current Literature suggests that Bariatric Surgery can reduce infectious complications in TKA, leading to better outcomes and less related costs treating of knee osteoarthritis in obese patients.

Post-bariatric pregnancy is associated with vitamin K1 deficiency, a case control study.

BACKGROUND: Maternal obesity is associated with adverse outcome for pregnancy and childbirths. While bariatric surgery may improve fertility and reduce the risk of certain pregnancy-related complications such as hypertension and gestational diabetes mellitus, there is a lack of evidence on the optimal nutritional monitoring and supplementation strategies in pregnancy following bariatric surgery. We aimed to assess the impact of bariatric surgery on micronutrients in post-bariatric pregnancy and possible differences between gastric bypass surgery and sleeve gastrectomy. METHODS: In this prospective case control study, we recruited 204 pregnant women (bariatric surgery n = 59 [gastric bypass surgery n = 26, sleeve gastrectomy n = 31, missing n = 2] and controls n = 145) from Akershus university hospital in Norway. Women with previous bariatric surgery were consecutively invited to study participation at referral to the clinic for morbid obesity and the controls were recruited from the routine ultrasound screening in gestational week 17-20. A clinical questionnaire was completed and blood samples were drawn at mean gestational week 20.4 (SD 4.5). RESULTS: The women with bariatric surgery had a higher pre-pregnant BMI than controls (30.8 [SD 6.0] vs. 25.2 [5.4] kg/m2, p < 0.001). There were no differences between groups regarding maternal weight gain (bariatric surgery 13.3 kg (9.6) vs. control 14.8 kg (6.5), p = 0.228) or development of gestational diabetes (n = 3 [5%] vs. n = 7 [5%], p = 1.000). Mean levels of vitamin K1 was lower after bariatric surgery compared with controls (0.29 [0.35] vs. 0.61 [0.65] ng/mL, p < 0.001). Multiadjusted regression analyses revealed an inverse relationship between bariatric surgery and vitamin K1 (B -0.26 ng/mL [95% CI -0.51, -0.04], p = 0.047) with a fivefold increased risk of vitamin K1 deficiency in post-bariatric pregnancies compared with controls (OR 5.69 [1.05, 30.77] p = 0.044). Compared with sleeve gastrectomy, having a previous gastric bypass surgery was associated with higher risk of vitamin K1 deficiency (OR 17.1 [1.31, 223.3], p = 0.030). CONCLUSION: Post-bariatric pregnancy is negatively associated with vitamin K1 with a higher risk of vitamin K1 deficiency in pregnancies after gastric bypass surgery compared with after sleeve gastrectomy. Vitamin K1 deficiency in post-bariatric pregnancy have potential risk of hypocoaguble state in mother and child and should be explored in future studies.

Influence of Bariatric Surgery on Gut Microbiota Composition and Its Implication on Brain and Peripheral Targets.

Obesity remains a significant global health challenge, with bariatric surgery remaining as one of the most effective treatments for severe obesity and its related comorbidities. This review highlights the multifaceted impact of bariatric surgery beyond mere physical restriction or nutrient malabsorption, underscoring the importance of the gut microbiome and neurohormonal signals in mediating the profound effects on weight loss and behavior modification. The various bariatric surgery procedures, such as Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), act through distinct mechanisms to alter the gut microbiome, subsequently impacting metabolic health, energy balance, and food reward behaviors. Emerging evidence has shown that bariatric surgery induces profound changes in the composition of the gut microbiome, notably altering the Firmicutes/Bacteroidetes ratio and enhancing populations of beneficial bacteria such as Akkermansia. These microbiota shifts have far-reaching effects beyond gut health, influencing dopamine-mediated reward pathways in the brain and modulating the secretion and action of key gut hormones including ghrelin, leptin, GLP-1, PYY, and CCK. The resultant changes in dopamine signaling and hormone levels contribute to reduced hedonic eating, enhanced satiety, and improved metabolic outcomes. Further, post-bariatric surgical effects on satiation targets are in part mediated by metabolic byproducts of gut microbiota like short-chain fatty acids (SCFAs) and bile acids, which play a pivotal role in modulating metabolism and energy expenditure and reducing obesity-associated inflammation, as well as influencing food reward pathways, potentially contributing to the regulation of body weight and reduction in hedonic eating behaviors. Overall, a better understanding of these mechanisms opens the door to developing non-surgical interventions that replicate the beneficial effects of bariatric surgery on the gut microbiome, dopamine signaling, and gut hormone regulation, offering new avenues for obesity treatment.

The impact of obesity-associated glycine deficiency on the elimination of endogenous and exogenous metabolites via the glycine conjugation pathway.

Background: Glycine is an integral component of the human detoxification system as it reacts with potentially toxic exogenous and endogenously produced compounds and metabolites via the glycine conjugation pathway for urinary excretion. Because individuals with obesity have reduced glycine availability, this detoxification pathway may be compromised. However, it should be restored after bariatric surgery because of increased glycine production. Objective: To examine the impact of obesity-associated glycine deficiency on the glycine conjugation pathway. We hypothesize that the synthesis rates of acylglycines from endogenous and exogenous sources are significantly reduced in individuals with obesity but increase after bariatric surgery. Methods: We recruited 21 participants with class III obesity and 21 with healthy weight as controls. At baseline, [1,2-13C2] glycine was infused to study the glycine conjugation pathway by quantifying the synthesis rates of several acylglycines. The same measurements were repeated in participants with obesity six months after bariatric surgery. Data are presented as mean ± standard deviation, and p-value< 0.05 is considered statistically significant. Results: Baseline data of 20 participants with obesity were first compared to controls. Participants with obesity were significantly heavier than controls (mean BMI 40.5 ± 7.1 vs. 20.8 ± 2.1 kg/m2). They had significantly lower plasma glycine concentration (168 ± 30 vs. 209 ± 50 µmol/L) and slower absolute synthesis rates of acetylglycine, isobutyrylglycine, tigylglycine, isovalerylglycine, and hexanoylglycine. Pre- and post-surgery data were available for 16 participants with obesity. Post-surgery BMI decreased from 40.9 ± 7.3 to 31.6 ± 6.0 kg/m2. Plasma glycine concentration increased from 164 ± 26 to 212 ± 38 µmol/L) and was associated with significantly higher rates of excretion of acetylglycine, isobutyrylglycine, tigylglycine, isovalerylglycine, and hexanoylglycine. Benzoic acid (a xenobiotic dicarboxylic acid) is excreted as benzoylglycine; its synthesis rate was significantly slower in participants with obesity but increased after bariatric surgery. Conclusion: Obesity-associated glycine deficiency impairs the human body's ability to eliminate endogenous and exogenous metabolites/compounds via the glycine conjugation pathway. This impairment is ameliorated when glycine supply is restored after bariatric surgery. These findings imply that dietary glycine supplementation could treat obesity-associated metabolic complications due to the accumulation of intramitochondrial toxic metabolites. Clinical trial registration: https://clinicaltrials.gov/study/NCT04660513, identifier NCT04660513.

Treatment of esophageal adenocarcinoma in patients with a history of bariatric surgery.

BACKGROUND: The relationship among obesity, bariatric surgery, and esophageal adenocarcinoma (EAC) is complex, given that some bariatric procedures are thought to be associated with increased incidence of reflux and Barrett's esophagus. Previous bariatric surgery may complicate the use of the stomach as a conduit for esophagectomy. In this study, we presented our experience with patients who developed EAC after bariatric surgery and described the challenges encountered and the techniques used. METHODS: We conducted a retrospective review of our institutional database to identify all patients at our institution who were treated for EAC after previously undergoing bariatric surgery. RESULTS: In total, 19 patients underwent resection with curative intent for EAC after bariatric surgery, including 10 patients who underwent sleeve gastrectomy. The median age at diagnosis of EAC was 63 years; patients who underwent sleeve gastrectomy were younger (median age, 56 years). The median time from bariatric surgery to EAC was 7 years. Most patients had a body mass index (BMI) score of >30 kg/m2 at the time of diagnosis of EAC; approximately 40% had class III obesity (BMI score > 40 kg/m2). Six patients (32%) had known Barrett's esophagus before undergoing a reflux-increasing bariatric procedure. Sleeve gastrectomy patients underwent esophagectomy with gastric conduit, colonic interposition, or esophagojejunostomy. Only 1 patient had an anastomotic leak (after esophagojejunostomy). CONCLUSION: Endoscopy should be required both before (for treatment selection) and after all bariatric surgical procedures. Resection of EAC after bariatric surgery requires a highly individualized approach but is safe and feasible.