Beneficial Effects Of Bariatric Surgery Research Articles

The PYY/Y2R-Deficient Mouse Responds Normally to High-Fat Diet and Gastric Bypass Surgery.

Background/Goals: The gut hormone peptide YY (PYY) secreted from intestinal L-cells has been implicated in the mechanisms of satiation via Y2-receptor (Y2R) signaling in the brain and periphery and is a major candidate for mediating the beneficial effects of bariatric surgery on appetite and body weight. Methods: Here we assessed the role of Y2R signaling in the response to low- and high-fat diets and its role in the effects of Roux-en-Y gastric bypass (RYGB) surgery on body weight, body composition, food intake, energy expenditure and glucose handling, in global Y2R-deficient (Y2RKO) and wildtype (WT) mice made obese on high-fat diet. Results: Both male and female Y2RKO mice responded normally to low- and high-fat diet in terms of body weight, body composition, fasting levels of glucose and insulin, as well as glucose and insulin tolerance for up to 30 weeks of age. Contrary to expectations, obese Y2RKO mice also responded similarly to RYGB compared to WT mice for up to 20 weeks after surgery, with initial hypophagia, sustained body weight loss, and significant improvements in fasting insulin, glucose tolerance, insulin resistance (HOMA-IR), and liver weight compared to sham-operated mice. Furthermore, non-surgical Y2RKO mice weight-matched to RYGB showed the same improvements in glycemic control as Y2RKO mice with RYGB that were similar to WT mice. Conclusions: PYY signaling through Y2R is not required for the normal appetite-suppressing and body weight-lowering effects of RYGB in this global knockout mouse model. Potential compensatory adaptations of PYY signaling through other receptor subtypes or other gut satiety hormones such as glucagon-like peptide-1 (GLP-1) remain to be investigated.

Targeting Bile Acid-Activated Receptors in Bariatric Surgery.

Bariatric surgical procedures, including Roux-en-Y gastric bypass and vertical sleeve gastrectomy, are currently the most effective clinical approaches to achieve a significant and sustainable weight loss. Bariatric surgery also concomitantly improves type 2 diabetes and other metabolic diseases such as nonalcoholic steatohepatitis, cardiovascular diseases, and hyperlipidemia. However, despite the recent exciting progress in the understanding how bariatric surgery works, the underlying molecular mechanisms of bariatric surgery remain largely unknown. Interestingly, bile acids are emerging as potential signaling molecules to mediate the beneficial effects of bariatric surgery. In this review, we summarize the recent findings on bile acids and their activated receptors in mediating the beneficial metabolic effects of bariatric surgery. We also discuss the potential to target bile acid-activated receptors in order to treat obesity and other metabolic diseases.

Development of murine bariatric surgery models: lessons learned

Roux-en-Y gastric bypass (RYGB) improves comorbidities such as diabetes and hypertension and lowers the risk of obesity-related cancers. To better understand the physiologic and genetic influences of bariatric surgery, a reliable murine model is needed that can be extended to genetically engineered mice. Given the complexity of these procedures, few researchers have successfully implemented these techniques beyond larger rodent models. The purpose of our study was to develop a technically feasible and reproducible murine model for RYGB and sleeve gastrectomy (SG). Mice were converted to liquid diet perioperatively without fasting and housed in groups on raised wire platforms. SG involved significant reduction of stomach volume followed by multilayer repair of the gastrotomy. RYGB procedure consisted of side-to-side, functional end-to-side bowel anastomoses and exclusion of the stomach medial to the gastroesophageal junction. Sham surgeries consisted of enterotomies and gastrotomy followed by primary repair without resection or rerouting. Survival after incorporation of the aforementioned techniques was 100% in the SG group and 41% in the RYGB group at 1 mo after surgery. Only 26% of RYGB mortality was attributed to leak, obstruction, or stricture; the majority of postoperative mortality was due to stress, dumping, or malnutrition. Much of the survival challenge for this surgical model was related to perioperative husbandry, which is to be expected given their small stature and poor response to stress. Utilization of the perioperative and surgical techniques described will increase survival and feasibility of these technically challenging procedures, allowing for a better understanding of mechanisms to explain the beneficial effects of bariatric surgery.

Gastrectomy with Roux-en-Y reconstruction as a lean model of bariatric surgery

BackgroundAltered enteroendocrine hormone responses are widely believed to underlie the beneficial effects of bariatric surgery in type 2 diabetes. While elevated postprandial glucagon-like peptide-1 (GLP-1) is considered one of the mediators, increased postprandial glucagon levels have recently been implicated. ObjectivesWe investigated hormonal responses in lean patients after prophylactic total gastrectomy (PTG), as a model of Roux-en-Y gastric bypass without the confounding effects of obesity or massive weight loss. SettingUniversity hospital, United Kingdom. MethodsTen participants after PTG and 9 healthy volunteers were recruited for oral glucose tolerance tests. Plasma glucose, insulin, GLP-1, peptide YY, glucose-dependent insulinotropic-polypeptide, glucagon, oxyntomodulin, glucagon(1-61), and glicentin levels were assessed using immunoassays and/or mass spectrometry. ResultsPTG participants exhibited accelerated plasma glucose appearance, followed, in 3 of 10 cases, by hypoglycemia (<3 mM glucose). Plasma GLP-1, peptide YY, glucose-dependent insulinotropic-polypeptide, glicentin, and oxyntomodulin responses were elevated, and glucagon appeared to rise in PTG participants when measured with a glucagon-specific enzyme-linked immunosorbent assay. We revisited the specificity of this assay, and demonstrated significant cross-reactivity with glicentin and oxyntomodulin at concentrations observed in PTG plasma. Reassessment of glucagon with the same assay using a modified protocol, and by liquid chromatography-mass spectrometry, demonstrated suppression of glucagon secretion after oral glucose tolerance tests in both PTG and control cohorts. ConclusionsCare should be taken when assessing glucagon levels in the presence of elevated plasma levels of other proglucagon products. Substantial elevation of GLP-1 and insulin responses after PTG likely contribute to the observed hypoglycemia, and mirror similar hormone levels and complications observed in bariatric weight loss patients.

Age-Related Effects of Bariatric Surgery on Early Atherosclerosis and Cardiovascular Risk Reduction.

Carotid intima-media thickness (CIMT) is increasingly used as a prognostic indicator for early atherosclerosis and the development of cardiovascular disease. The objective of this study is to assess the exact effects of bariatric surgery on CIMT reduction in different age groups. CIMT was measured just proximal to the bifurcation of the carotid artery in 166 patients with mean body mass index of 43.4kg/m2 before and at 6 and 12months after bariatric surgery. Preoperative CIMT and Framingham Risk Score (FRS) were compared to measurements at 6 and 12months, postoperatively. Impact of age on CIMT change and cardiovascular risk reduction was analyzed. Median follow-up was 12months; 12% were lost to follow-up. Mean CIMT values at 12months after bariatric surgery were significantly lower compared to baseline (0.619 vs. 0.587mm, p=0.005 in women and 0.675 vs. 0.622mm, p=0.037 in men, respectively), and these effects were statistically significant in all age groups. The mean reduction of CIMT for patients <50years at 12months was 0.043mm (-7.0%), while CIMT was reduced with 0.013mm for patients ≥50years (-1.9%, p=0.022). At 12months after bariatric surgery, FRS had decreased with 52% in patients <50years as compared with 35% in patients ≥50years (p=0.025). Bariatric surgery resulted in a significant CIMT decrease in patients with morbid obesity in all evaluated age categories. These beneficial effects of bariatric surgery were more pronounced in younger patients, while cardiovascular risk reduction by bariatric surgery appeared inferior in patients of 50years and older.

Outcome of laparoscopic gastric bypass in obese and diabetic patients: when surgery fails

The beneficial effects of bariatric surgery on diabetes and obesity have been widely demonstrated in the literature. The aim of our study was to evaluate the rate of failure of laparoscopic gastric bypass both in terms of weight loss and metabolic remission after one follow-up year. A longitudinal, multicenter prospective study was carried out on 771 patients affected by pathological obesity. The following parameters were recorded for each patient before surgery: anthropometric, metabolic, social, smoking habits and previous failure of other bariatric procedures. After 1 follow-up year, final weight, final Body Mass Index (BMI), final percentage of lost excess body weight and percentage of lost BMI were evaluated. Statistical analysis showed a correlation between BMI>50 kg/m2, presence of metabolic syndrome, presence of diabetes, gastric pouch volume greater than 60 mL and failure of weight loss outcome. Statistical analysis of metabolic failure has recognized a high preoperative glycated hemoglobin percentage (HbA1c%) value as a statistically significant negative predictive factor. Bariatric Surgery is the most effective treatment for weight loss and metabolic improvement. However, in our study, surgery did not achieve the expected outcome in patients with specific metabolic, anthropometric and surgical characteristics (BMI>50 kg/m2, presence of metabolic syndrome, presence of T2DM with high preoperative HbA1c% level and gastric pouch volume greater than 60 mL).

Bile acid disease: the emerging epidemic.

Our objective was to review advances in bile acids in health and disease published in the last 2 years. Bile acid diarrhea (BAD) is recognized as a common cause of chronic diarrhea, and its recognition has been facilitated by development of new screening tests. Primary BAD can account for 30% of cases of chronic diarrhea. The mechanisms leading to BAD include inadequate feedback regulation by fibroblast growth factor 19 (FGF-19) from ileal enterocytes, abnormalities in synthesis or degradation of proteins involved in FGF-19 regulation in hepatocytes and variations as a function of the bile acid receptor, TGR5 (GPBAR1). SeHCAT is the most widely used test for diagnosis of BAD. There has been significant validation of fasting serum FGF-19 and 7 α-hydroxy-cholesten-3-one (C4), a surrogate measure of bile acid synthesis. Bile acid sequestrants are the primary treatments for BAD; the farnesoid X-receptor-FGF-19 pathway provides alternative therapeutic targets for BAD. Bile acid-stimulated intestinal mechanisms contribute to the beneficial effects of bariatric surgery on obesity, glycemic control and the treatment of recurrent Clostridium difficile infection. Renewed interest in the role of bile acids is leading to novel management of diverse diseases besides BAD.

Techniques of Sleeve Gastrectomy and Modified Roux-en-Y Gastric Bypass in Mice

Obesity is a major public health issue, with a prevalence of 4 to 28% for men and 6.2 to 36.5% for women in Europe (from 2003 to 2008). Morbid obesity is frequently associated with metabolic complications, such as type 2 diabetes, hypertension, and dyslipidemia, reducing life expectancy and quality. In the absence of any effective noninvasive treatments, bariatric surgery is a valuable therapeutic option for patients with morbid obesity (body mass index (BMI) >40 kg/m2), leading to long-term, sustained weight loss and improvements in metabolic complications. However, the underlying cellular and molecular mechanisms sustaining the beneficial effects of bariatric surgery are not yet fully understood. Due to the numerous genetically-modified strains available, the mouse model is the most convenient animal model to explore the molecular mechanisms behind the pleiotropic beneficial effects of bariatric surgeries. Here, we detailed the optimized healthcare methods and surgical protocols in mice for the two most widely-used bariatric surgeries: the sleeve gastrectomy and the modified Roux-en-Y gastric bypass. Deciphering the molecular mechanisms underlying the therapeutic effects of bariatric surgeries offers the promise of identifying new therapeutics targets.

Techniques of Sleeve Gastrectomy and Modified Roux-en-Y Gastric Bypass in Mice.

Obesity is a major public health issue, with a prevalence of 4 to 28% for men and 6.2 to 36.5% for women in Europe (from 2003 to 2008). Morbid obesity is frequently associated with metabolic complications, such as type 2 diabetes, hypertension, and dyslipidemia, reducing life expectancy and quality. In the absence of any effective noninvasive treatments, bariatric surgery is a valuable therapeutic option for patients with morbid obesity (body mass index (BMI) >40 kg/m2), leading to long-term, sustained weight loss and improvements in metabolic complications. However, the underlying cellular and molecular mechanisms sustaining the beneficial effects of bariatric surgery are not yet fully understood. Due to the numerous genetically-modified strains available, the mouse model is the most convenient animal model to explore the molecular mechanisms behind the pleiotropic beneficial effects of bariatric surgeries. Here, we detailed the optimized healthcare methods and surgical protocols in mice for the two most widely-used bariatric surgeries: the sleeve gastrectomy and the modified Roux-en-Y gastric bypass. Deciphering the molecular mechanisms underlying the therapeutic effects of bariatric surgeries offers the promise of identifying new therapeutics targets.

Targeting the gut to treat obesity and its metabolic comorbidities: focus on bariatric surgery - view from the chair.

Over the past decade, bariatric surgery emerged as the most effective treatment modality for obesity and its complications, especially type 2 diabetes. Initially introduced on the basis of their capacity to restrict food intake and/or induce dietary fat malabsorption, the current bariatric surgery procedures result in many more physiological changes that may also partly explain their potent and sustained anti-obesity and anti-diabetic effects. In the session 2 of the 17th International Symposium of the Université Laval Research Chair in Obesity, outstanding speakers have provided insight into novel clinical and pathophysiological aspects in bariatric surgery. Dr Blandine Laferrère discussed the growing body of evidence implicating incretin hormones in the anti-diabetic effects of bariatric surgery and Dr Hans-Rudolf Berthoud explored emerging evidence suggesting that bariatric surgery may reset the defended body mass set point. As data are rapidly accruing about the beneficial effects of bariatric surgery, these procedures not only take a greater place in clinical practice, but they also offer outstanding occasions to peek into the intricate and complex links between diet and gastrointestinal track, and obesity and its complications.

Associations of Circulating PYY3-36 Concentrations with Metabolic Syndrome in Extremely Obese Subjects.

The gut hormone peptide YY3-36 (PYY3-36) plays major roles in regulation of appetite and energy metabolism, mediates beneficial effects of bariatric surgery, and may be a potential weight-reducing and glucose-modulating therapy. Obesity may influence the metabolic expression of circulating PYY3-36 and metabolic markers. We studied the relationship of PYY3-36 concentrations with metabolic syndrome (MetSyn) components, lipids, insulin resistance, and inflammatory biomarkers in subjects with extreme obesity. We measured MetSyn components and PYY3-36, lipids, hormones, homeostasis model assessment (HOMA) index, and inflammatory biomarkers in consecutively referred patients (180 women and 111 men) aged 18-78 years with body mass index (BMI) ≥40 kg/m2. Associations of PYY3-36 to components, insulin resistance, and biomarkers were examined with partial correlations and linear regression. PYY3-36 concentrations were not related to MetSyn components, HOMA index, or to inflammatory biomarker or leptin concentrations. PYY3-36 concentrations correlated with systolic blood pressure (r = 0.21; P < 0.0001) after adjustment for age and gender. In linear regression analysis, PYY3-36 concentrations were associated with systolic blood pressure after adjustment for age, gender, and central obesity in the entire sample (Beta 0.21; 95% CI 0.09-0.34) as well as in subjects not taking blood pressure-lowering medication (Beta 0.19; 95% CI 0.04-0.36). These associations were not statistically significant in the small subset of participants (22%) with type 2 diabetes. In extremely obese patients, fasting PYY3-36 concentrations were linked to systolic blood pressure, but not to other components of MetSyn, suggesting divergence between pathways of blood pressure and glucose/body weight regulation. However, this finding will need to be further investigated.

Beneficial Effects of Bariatric Surgery on Cardiac Structure and Function in Obesity.

Bariatric surgery is being considered as a therapeutic option for morbidly obese patients. Data are accumulating showing that this surgical intervention may improve in major cardiovascular morbidity and mortality. We evaluated the effects of bariatric surgery on left ventricular (LV) structure and function including LV mechanics in obese patients. Thirty-seven patients (age=36±10years; male:female=11:26) undergoing bariatric surgery were enrolled. Echocardiography was performed before and after at least 1year of bariatric surgery. Conventional echocardiographic parameters, including tissue Doppler measurements, were measured. LV global longitudinal, circumferential, and radial deformations were assessed utilizing 2D speckle tracking software. Patients decreased body mass index by 11.8±4.7 over 15.6±5.5months. Bariatric surgery led to significant decreases in left ventricular (LV) size and mass (51.0±3.3 to 49.1±3.4mm, p<0.001 for LV end-diastolic dimension; 192.6±33.5 to 146.2±29.1g, p<0.001 for LV mass), and increases were noted in the ratio of early-to-late diastolic mitral inflow (E/A), early diastolic tissue Doppler velocity (Em), and LV longitudinal strain (1.42±0.52 to 1.59±0.56, p=0.04 for E/A ratio; 9.7±2.0 to 11.0±2.4cm/s, p<0.001 for Em; 14.1±1.9 to 16.2±1.4%, p<0.001 for longitudinal strain). Changes of LV longitudinal strain were related to LV mass reduction (p=0.04). However, LV ejection fraction, LV circumferential, and radial strains were all comparable at follow-up. Significant weight loss by bariatric surgery was associated with improved LV structure and function in obese patients, suggesting potential favorable effects of bariatric surgery to prevent future cardiovascular events.

Peripheral circadian misalignment: contributor to systemic insulin resistance and potential intervention to improve bariatric surgical outcomes.

Thirteen percent of the world's population suffers from obesity and 39% from being overweight, which correlates with an increase in numerous secondary metabolic complications, such as Type 2 diabetes mellitus. Bariatric surgery is the most effective treatment for severe obesity and results in significant weight loss and the amelioration of obesity-related comorbidities through changes in enteroendocrine activity, caloric intake, and alterations in gut microbiota composition. The circadian system has recently been found to be a critical regulatory component in the control of metabolism and, thus, may potentially play an important role in inappropriate weight gain. Indeed, some behaviors and lifestyle factors associated with an increased risk of obesity are also risk factors for misalignment in the circadian clock system and for the metabolic syndrome. It is thus possible that alterations in peripheral circadian clocks in metabolically relevant tissues are a contributor to the current obesity epidemic. As such, it is plausible that postsurgical alterations in central circadian alignment, as well as peripheral gene expression in metabolic tissues may represent another mechanism for the beneficial effects of bariatric surgery. Bariatric surgery may represent an opportunity to identify changes in the circadian expression of clock genes that have been altered by environmental factors, allowing for a better understanding of the mechanism of action of surgery. These studies could also reveal an overlooked target for behavioral intervention to improve metabolic outcomes following bariatric surgery.

Abstract 1767: Racial/ethnic disparities of obesity in a breast clinic population: Consideration for weight loss program in improving clinical outcomes

Abstract Introduction: Accumulating evidence suggest that obesity is associated with breast cancer diagnosis, recurrence, and mortality. Obese subjects with genetic predisposition may need more aggressive weight loss management, such as bariatric surgery. Therefore, the primary aim of this study was to assess the racial/ethnic disparities in obesity and the prevalence of breast cancer study participants who may be eligible for bariatric surgery. Methods: In three clinic-based studies conducted at University of Miami during 2008 to 2015, we evaluated 462 healthy controls and 975 breast cancer patients. Genotyping data of two obesity-related genes (FTO and MC4R) were also evaluated. Race/ethnicity and obesity-related comorbidities were self- reported. Body Mass Index (BMI) was calculated as kg/m2. The classification of BMI was: (1) &amp;lt; 18.5, underweight; (2) 18.5-24.9, normal weight; (3) 25.0-29.9, overweight; (4) 30.0-34.9, class I obesity; (5) 35.0-39.9, class II obesity; and (6) ≥ 40.0, class III obesity. The NIH eligibility for bariatric surgery was for class II obese subjects with obesity-related comorbidities and class III obese subjects. Results: The study consists of 70.0% Hispanic whites (HW), 21.7% black or African American (AA), and 6.4% non-Hispanic whites (NHW). Mean and SD of age was 54.1± 9.9 years and mean BMI was 29.0±6.1 kg/m2. Overall, about 11.1% of study participants met criteria for bariatric surgery and there were significant racial/ethnic disparities (19.7% AA, 8.5% HW, 8.8% NHW, and 17.2% others; p&amp;lt;0.0001). Subgroup analysis observed increased BMI at follow up (29.60 vs. 29.16 kg/m2, p = 0.00229). Women with the AA risk genotype of rs1121980 (FTO gene) had 3.6-fold higher risk of obesity class II or III compared to those with the GG genotype (p = 0.00393). Conclusion: In addition to cancer risk, obesity is a major risk factor for cancer treatment-related side effects and worse survival. Our results suggest that at least 11% of breast cancer patients may be eligible for bariatric surgery. Considering some other beneficial effects of bariatric surgery on physical quality of life, metabolic syndrome, diabetes, and microbiome, future studies will consider weight loss and bariatric surgery programs in breast cancer patients, particularly in underserved minorities with higher obesity rate and worse survival. Citation Format: Carolina Puyana Barcha, Eunkyung Lee, Cristiane Takita, Jean L. Wright, Wei Zhao, Isildinha M. Reis, Jennifer J. Hu. Racial/ethnic disparities of obesity in a breast clinic population: Consideration for weight loss program in improving clinical outcomes. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1767.

Bacterial Lipopolysaccharide, Lipopolysaccharide-Binding Protein, and Other Inflammatory Markers in Obesity and After Bariatric Surgery.

Obesity is associated with altered gut microbiota and low-grade inflammation. A key factor in the inflammatory process is endotoxin lipopolysaccharide (LPS). Plasma LPS levels and sensory agent lipopolysaccharide-binding protein (LBP) are shown to be elevated in obesity. This elevation may be due to increased intestinal permeability and incorporation of a high-fat diet accompanied by overfeeding. Bariatric surgery has become a popular treatment option that results in stable weight loss and improvement of obesity-related conditions. Studies outlined in this review show reduced LPS and LBP levels after different bariatric procedures. LPS receptor CD14 and mRNA expression toll-like receptor 2 (TLR2) and toll-like receptor 4 (TLR4) were also shown to have reduced levels following surgery. Changes in LPS and LPS components after bariatric surgery are shown to be linked to the surgical technique of the procedure and restriction of caloric intake. Additionally, changes in the gut microbiota provide some insight to the reduction of inflammatory markers after surgery. The beneficial effects of bariatric surgery are not dependent on weight loss alone. The inflammatory pathway plays a key role in the improvement of metabolic complications following surgery that should be further examined. Additional research is needed to evaluate short- and long-term changes of LPS and LPS components after bariatric surgery, including how those assessments can be applied to clinical practice.

Inhibition of inflammation may enhance nitric oxide availability in patients undergoing bariatric surgery for weight loss.

Weight loss surgery is the most effective treatment for morbid obesity. The mechanisms underlying the beneficial cardiovascular effects are poorly understood, although inhibition of inflammatory markers has been demonstrated. We hypothesized that anti-inflammatory and antioxidative stress reactions are responsible for the beneficial effects of bariatric surgery that have been shown in clinical trials. The inflammatory system was studied by measuring mRNA levels of E-selectin, tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and in a cell line (HUVEC-CS) of human umbilical vein endothelial cells that were incubated for 4h with pools of serum, collected before and 3months after surgery, from 20 women who underwent bariatric surgery for weight loss. The oxidative stress pathway was examined by mRNA expression of NADPH oxidase (P22(phox) ), paraoxonase (PON2), superoxide dismutase 2 (SOD2), glutathione peroxidase (GPx) and catalase following incubation of the cells for 4h with serum pools. The nitric oxide (NO) pathway was studied by measuring mRNA levels of inducible NOS and endothelial NOS and by determining nitrite and nitrate levels. To study the functional behaviour of endothelial cells under stress, primary human umbilical vein endothelial cells (PECs) were incubated with the serum pools for 48h, with lipopolysaccharide (LPS) for the last 4h. The inflammatory system: incubation of HUVEC-CS cells with serum from women who underwent bariatric surgery led to a significant decrease in mRNA expression of E-selectin and IL-6 postsurgery. Stimulation of PECs with LPS in the presence of serum from women who underwent bariatric surgery caused a more significant difference in E-selectin and TNF-α mRNA expression before and after surgery. The antioxidant system: incubation of HUVEC-CS cells with serum from women who underwent bariatric surgery did not lead to any difference in mRNA expression of P22(phox) , PON2, SOD2, GPx or catalase. Stimulation of PECs with LPS showed that obese women had higher levels of P22(phox) , PON2 and the antioxidant enzymes SOD2, GPx and catalase before and after surgery, compared to the control group. The NO pathway: HUVEC-CS cells incubated with serum from women who underwent bariatric surgery secreted higher nitrite/nitrate levels compared to presurgery serum (P=0.04). Inhibition of inflammation and enhanced availability of NO 3months after bariatric surgery could partly explain the beneficial effects of surgery for weight loss.

Effects of Laparoscopic Roux-en-Y Gastric Bypass on Anthropometric Characteristics, Hypertension, Type 2 Diabetes Mellitus and Metabolic Syndrome: An Iranian Experience

 &#x0D; Background: Surgically induced weight loss is a treatment option for the management of obesity and the related common disorders. This study evaluated the beneficial effects of bariatric surgery on metabolic profile and the prevalence of metabolic syndrome (MetS) among Iranian patients.&#x0D; Materials and Methods: A prospective observational study was performed on 26 morbidly obese patients scheduled for bariatric surgery, using laparoscopic Roux-en-Y gastric bypass (LRYGB). The parameters of hypertension, type 2 diabetes mellitus (T2DM), hyperlipidemia, MetS prevalence, and anthropometric measurements of Iranian patients, were recorded, at the preoperative visit and in follow-ups. The follow-up was performed for a median of 12 months, and the change in MetS prevalence and its componnts were assesed.&#x0D; Results: LRYGB induced a mean weight loss of 69.0±21.2%, after 12 months. Preoperative MetS was diagnosed in 21 patients (84%) and decreased to 6 patients (24%) after LRYGB (P=0.001). Likewise, the prevalence of hypertension was significantly decreased from 76% (pre-LRYGB values) to 20% (post-LRYGB values) (P=0.001). The prevalence of T2DM was also decreased from 20% to 8% (P=0.5).&#x0D; Conclusion: According to our results, RYGB produced a rapid and significant weight loss and improvement in hypertension and MetS within one year but there was a controversy about the improvement of T2DM, in Iranian morbidly obese patients.

Hypogonadism as an additional indication for bariatric surgery in male morbid obesity?

Male obesity is often associated with reduced levels of circulating total (TT) and calculated free testosterone (cFT), with normal/reduced gonadotropins. Bariatric surgery often improves sex steroid and sex hormone-binding globulin (SHBG) levels. The aim of this study was to assess the effects of bariatric surgery on waist circumference (WC) and BMI, and on TT levels, in morbidly obese men, stratified, according to the gonadal state, in eugonadal and hypogonadal (TT<8 nmol/l) subjects. A cohort of morbidly obese patients (29 with hypogonadism (HG) and 26 without) undergoing bariatric surgery (37, 10, 6, and 2, with Roux-en-Y gastric bypass, laparoscopic adjustable gastric banding, biliopancreatic diversion and gastric sleeve, respectively) was studied at 6 and 12 months from the operation. Anthropometric parameters (weight, BMI, WC) and sex hormones (gonadotropins, TT, cFT, estradiol (E2), SHBG) were assessed. WC was the only parameter significantly correlated with androgens, but not with E2, SHBG, and gonadotropins, at baseline. After surgery, a significant increase in TT, cFT, and SHBG, accompanied by a decrease in E2, was evident in the two groups. However, both TT and cFT, but not E2, SHBG, and gonadotropin variations, were significantly higher in the hypogonadal group at follow-up, with an overall 93% complete recovery from HG. Reduction in WC, but not BMI, was significantly greater in hypogonadal men (ΔWC=-29.4±21.6 vs -14.4±17.4 at 12 months, P=0.047). Recovery from obesity-associated HG is one of the beneficial effects of bariatric surgery in morbidly obese men. The present findings suggest that the gonadal state is a predictor of WC decrease after bariatric surgery.

Obesity. Beneficial effects of bariatric surgery are mediated by FXR signalling.

Obesity. Beneficial effects of bariatric surgery are mediated by FXR signalling.

The Role of Gut Hormone Peptide YY in Energy and Glucose Homeostasis: Twelve Years On

Although the role of peptide YY (PYY) as a regulator of energy homeostasis was first highlighted only in 2002, our understanding of the physiological role of PYY has since rapidly advanced. In recent years, insights from mechanistic studies in patients undergoing bariatric surgery, from pancreatic islet research, from functional neuroimaging studies, and from exercise research have greatly added to the field, and these areas provide the focus of discussion for this narrative review. We critically discuss recent findings relating to the role of PYY in mediating the beneficial effects of bariatric surgery, the role of PYY in glucose homeostasis, the role of hepatoportal PYY in mediating its central physiological effects, the specific modulation of brain regions by PYY, and the exercise-induced PYY response.