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The mechanisms by which leptin influences energy homeostasis are not entirely understood. Several observations indicate that proopiomelanocortin (POMC) is involved in the regulation of food intake and may be a mediator of leptin action. To further study this interaction, a sensitive solution hybridization assay was used to compare the levels of POMC mRNA in the medial basal hypothalamus (MBH) of lean (+/+, +/faf) and obese leptin receptor-deficient (faf/faf) rats. POMC peptide products were also measured by RIA in the same animals. Cytoplasmic POMC RNA levels were significantly reduced by 53% in obese rats as compared with lean controls: 0.30 ± 0.04 vs. 0.64 ± 0.07 pg/µg total RNA (p < 0.02). Significant reductions in mean concentrations of hypothalamic POMC-derived peptides from the same dissections were detected in the obese rats vs. lean controls: α-MSH 1.77 ± 0.07 vs. 2.34 ± 0.10; β-EP 4.06 ± 0.24 vs. 5.86 ± 0.36; γ3-MSH 5.32 ± 0.20 vs. 6.52 ± 0.12 ng/mg protein (p < 0.001). To determine whether leptin stimulates POMC gene transcription, the acute effect of an intracerebroventricular (i.c.v.) injection of leptin (5 µg) on POMC primary transcript was quantified in the MBH of lean rats after a 16-hour fast. There was a significant 167% increase in mean POMC hnRNA levels 3 h after i.c.v. leptin injection (1.15 ± 0.22 pg/MBH; p < 0.02), but not after 1 h (0.76 ± 0.08 pg/MBH), compared to saline controls (0.69 ± 0.08 pg/MBH). 4 h after the injection of leptin, POMC hnRNA was still increased, but to a lesser extent (140%), as compared with control animals (p = 0.006). These studies demonstrate for the first time in the leptin receptor-deficient rat that there is an associated decrease in POMC gene expression and peptide levels in the MBH. Furthermore, the acute increase in the levels of POMC primary transcript in non-obese rats after a single i.c.v. injection of leptin supports a role for leptin in the regulation of POMC gene transcription. Taken together, these studies provide further evidence that POMC is an important mediator of the effects of leptin on food intake and energy expenditure.

Bariatric surgery improves glucose homeostasis and alters gut hormones partly independent of weight loss. Leptin plays a role in these processes; levels are decreased following bariatric surgery, creating a relative leptin insufficiency. We previously showed that leptin administration in a weight-reduced state after Roux-en-Y gastric bypass (RYGB) caused no further weight loss. Here, we discuss the impact of leptin administration on gut hormones, glucostasis, and appetite. Weight stable women after RYGB were randomized to receive placebo or recombinant human metreleptin (0.05 mg/kg twice daily). At weeks 0 and 16, a liquid meal challenge was performed. Glucose, insulin, C-peptide, GLP-1, PYY, glucagon, and ghrelin (total, acyl, and desacyl) were measured fasting and postprandially. Appetite was assessed using a visual analog scale. Mean post-op period was53±2.3months; mean BMI was34.6±0.2 kg/m2. At 16 weeks, there was no significant change in weight within or between groups. Fasting PYY was significantly different between groups and the leptin group had lower sweets craving at week 16 than the placebo group (P<0.05). No other differences were observed. Leptin replacement does not alter gut hormones or glucostasis but may diminish sweet cravings compared to placebo in this population of post-RYGB women.

Background: Relatively little is known about changes in eating behavior or hormonal responses to food following bariatric surgery in adolescents. Objective: This study compared eating behavior and hormones among adolescents in a bariatric surgery program with those in nonoverweight control adolescents and evaluated changes before and after laparoscopic adjustable gastric banding (LAGB). Design: Fasting leptin, peptide YY (PYY), and ghrelin concentrations were obtained, and postprandial ghrelin and PYY area under the curve (AUC) were assessed following a single-item breakfast. Intake from an ad libitum lunchtime multi-item meal was measured. Results: Compared with controls (n = 11), all presurgical candidates (n = 20) had significantly greater fasting leptin and lower AUC ghrelin but similar fasting ghrelin, PYY, and AUC PYY. Preoperative candidates did not differ from controls in total energy consumed during the test meal. Postoperatively, among the 11 participants with data both before and after surgery, BMI (in kg/m 2 ) decreased by 3.5 (P , 0.001), significantly less energy was consumed in the test meal, and a smaller number of foods were selected. AUC ghrelin and PYY did not significantly change before or after LAGB. Conclusions: Few significant short-term changes were observed in appetitive hormones after LAGB. It is unclear whether objective measures of eating behavior will prove useful in evaluating the impact of bariatric surgery on outcomes. This trial was registered at clinicaltrials.gov as CT00764127. Am J Clin Nutr doi: 10. 3945/ajcn.113.061762.

Marked improvement in glycemic control occurs in patients with type 2 diabetes mellitus shortly after Roux-en-Y gastric bypass surgery (RYGB) and before there is major weight loss. The objective of this study was to determine whether the magnitude of this change is primarily due to caloric restriction or is unique to the surgical procedure. We studied eleven subjects who underwent RYGB and fourteen subjects mean-matched for BMI, HbA1c, and diabetes duration who were admitted to our inpatient research unit and given a very low–calorie diet (VLCD) of 500 kcal/day with a macronutrient content similar to that consumed by patients after RYGB. Frequently sampled intravenous glucose tolerance tests were performed before and after interventions. Both groups lost an equivalent amount of weight over a mean study period of 21 days. Insulin sensitivity, acute insulin secretion after intravenous glucose administration, and β-cell function as determined by disposition index improved to a similar extent in both groups. Likewise, changes in fasting glucose and fructosamine levels were similar. Based on these data, VLCD improves insulin sensitivity and β-cell function just as well as RYGB in the short term.

New insights into the complex metabolic circuitry of energy homeostasis have refined our understanding of the pathophysiology of obesity. Some of these insights regarding energy homeostasis are bas...

Objective Obese individuals have high levels of circulating leptin and are resistant to the weight-reducing effect of leptin administration at physiological doses. Although Roux-en-Y gastric bypass (RYGB) is an effective weight loss procedure, there is a plateau in weight loss and most individuals remain obese. This plateau may be partly due to the decline in leptin resulting in a state of relative leptin insufficiency. The main objective of this study was to determine whether leptin administration to post-RYGB patients would promote further weight reduction. Design and Methods This was a randomized, double-blind, placebo-controlled cross-over study of 27 women who were at least 18 months post-RYGB and lost on average 30.8% of their pre-surgical body weight. Subjects received either leptin or placebo via subcutaneous injection twice daily for 16 weeks, then crossed over to receive the alternate treatment for 16 weeks. Results Weight change after 16 weeks of placebo was not significantly different from that after 16 weeks of leptin. No changes were observed in percent fat mass, resting energy expenditure, thyroid hormones, or cortisol levels. Conclusions Contrary to our hypothesis, we did not observe a significant effect of leptin treatment on body weight in women with relative hypoleptinemia after RYGB.

Among patients with nontuberculous mycobacterial lung disease is a subset of previously healthy women with a slender body morphotype, often with scoliosis and/or pectus excavatum. We hypothesize that unidentified factors predispose these individuals to pulmonary nontuberculous mycobacterial disease.To compare body morphotype, serum adipokine levels, and whole-blood cytokine responses of patients with pulmonary nontuberculous mycobacteria (pNTM) with contemporary control subjects who are well matched demographically.We enrolled 103 patients with pNTM and 101 uninfected control subjects of similar demographics. Body mass index and body fat were quantified. All patients with pNTM and a subset of control subjects were evaluated for scoliosis and pectus excavatum. Serum leptin and adiponectin were measured. Specific cytokines important to host-defense against mycobacteria were measured in whole blood before and after stimulation.Patients with pNTM and control subjects were well matched for age, gender, and race. Patients with pNTM had significantly lower body mass index and body fat and were significantly taller than control subjects. Scoliosis and pectus excavatum were significantly more prevalent in patients with pNTM. The normal relationships between the adipokines and body fat were lost in the patients with pNTM, a novel finding. IFN-γ and IL-10 levels were significantly suppressed in stimulated whole blood of patients with pNTM.This is the first study to comprehensively compare body morphotype, adipokines, and cytokine responses between patients with NTM lung disease and demographically matched controls. Our findings suggest a novel, predisposing immunophenotype that should be mechanistically defined.

Cite this article as: John E. Connett, Sayeed Ikramuddin, Avis J. Thomas, John P. Bantle, Charles J. Billington, Keong Chong, Lee-Ming Chuang, William B. Inabnet III, Robert W. Jeffery, Judith Korner, Patricia S. Laqua, Wei-Jei Lee, Daniel B. Leslie, WITHDRAWN: A Randomized Trial Comparing Roux-en-Y Gastric Bypass to Intensive Medical Management in Obese Patients with Type 2 Diabetes Mellitus, Surgery for Obesity and Related Diseases, http://dx.doi.org/10.1016/j.soard.2012.08.011

Cite this article as: Avis J. Thomas, Heather A. Bainbridge, Joyce L. Schone, Shu-Chun Chen, Amy E. Reynolds, John E. Connett, Sayeed Ikramuddin, Wei-Jei Lee, Michael D. Jensen, Judith Korner, WITHDRAWN: Recruitment and Screening for a Randomized Trial Comparing Roux-en-Y Gastric Bypass to Intensive Medical Management for Treatment of Type 2 Diabetes, Surgery for Obesity and Related Diseases, http://dx.doi. org/10.1016/j.soard.2012.08.010

Bariatric surgery improves glucose homeostasis, but the mechanism of action is poorly understood. The aim of this study was to assess the effect of sleeve gastrectomy (SG) on glucose homeostasis in two obese populations of rats.Two strains of rats [Zucker fatty (ZF) and Zucker diabetic fatty (ZDF)] were each divided into two groups: sham and SG. Food intake was measured daily, and weight was measured bi-weekly. Oral glucose tolerance testing (OGTT) was performed before and 45 days after surgery.In both strains of rats, there was no statistical difference in food intake and weight gain between the sham and SG rodents before and after surgery. In ZF rats, there was no change in fasting glucose or OGTT area under the curve (AUC) before or 45 days after surgery. In the ZDF rodents, the mean preoperative fasting glucose and OGTT AUC was 204 ± 25 and 25,441 ± 2,648, respectively. At 45 days after surgery, mean fasting glucose significantly increased in the sham (sham = 529 ± 26, p = 0.0003) but not in the SG rodents (SG = 289 ± 46, p = 0.1113). In ZDF sham animals, OGTT at 45 days showed a higher AUC compared to before surgery (44,983 ± 6,338, p = 0.006), whereas in ZDF SG rodents, the increase in AUC glucose approached but did not reach statistical significance (35,553 ± 3,925, p = 0.06).In ZF and ZDF rodents, SG did not influence food intake and weight evolution. In ZDF rodents, diabetes progressed in the sham group but not in the SG group.

Dopaminergic hypofunction and hyperprolactinaemia have been implicated in the pathogenesis of obesity and glucose intolerance. The aim of this pilot study was to determine the efficacy of cabergoline, a dopamine receptor agonist, on body weight and glucose tolerance in obese non-diabetic persons with normal plasma prolactin levels.This 16-week double blind, placebo-controlled pilot study randomized non-diabetic obese adults (body mass index 30-42 kg/m(2) ) to placebo or cabergoline (0.25 mg twice weekly for 4 weeks followed by 0.5 mg twice weekly for the next 12 weeks). Of 40 subjects enrolled, 29 completed 16 weeks: 16 randomized to placebo and 13 to cabergoline. All subjects were counselled on a 500 kcal/day calorie deficit diet. A 75-g oral glucose tolerance test was performed at baseline and at 16 weeks.As expected, prolactin levels decreased after cabergoline (p0.001). Weight loss was similar after placebo compared with cabergoline treatment: 1.0 vs. 1.2% body weight, respectively. Fasting glucose levels did not differ between groups after treatment, however, 90-min postprandial glucose and insulin decreased in the cabergoline group only (p = 0.029). HOMA-IR (homeostasis model of assessment) increased by 40% after placebo and 1.5% after cabergoline treatment.This pilot study suggests that cabergoline therapy may improve glucose tolerance independent of weight loss, however, a larger, longer term study of dopamine receptor agonist therapy in obese individuals is warranted to confirm this finding.

Hypothalamic obesity is a potential sequela of craniopharyngioma, arising from hypothalamic damage inflicted by either the tumor and/or its treatment. The marked weight gain that characterizes this disorder appears to result from impaired sympathoadrenal activation, parasympathetic dysregulation, and other hormonal and hypothalamic disturbances that upset the balance between energy intake and expenditure. Given hypopituitarism is commonly present, careful management of hormonal deficits is important for weight control in these patients. In addition, diet, exercise, and pharmacotherapy aimed at augmenting sympathetic output, controlling hyperinsulinism, and promoting weight loss have been used to treat this disease, but these measures rarely lead to sustained weight loss. While surgical interventions have not routinely been pursued, emerging data suggests that surgical weight loss interventions including Roux-en-Y gastric bypass can be safely and effectively used for the management of hypothalamic obesity in patients with craniopharyngioma.

The growing awareness of the obesity epidemic as a critical matter of health concern has prompted research into the mechanisms underlying energy homeostasis and the pathophysiology of obesity. Food intake, energy expenditure, and fat storage all are regulated by a complex neuroendocrine system. It is now recognized that in addition to central neurohumoral pathways, adipose tissue has an independent endocrine function that contributes to energy homeostasis. Moreover, adipose tissue exerts inflammatory effects that are linked to the most important health problems associated with obesity, including cardiovascular disease and type 2 diabetes mellitus, each of which has the potential to confer long-term morbidity and increased mortality risks. This inflammatory effect of adipose tissue is more pronounced in abdominal obesity, which is reflected by the heightened cardiometabolic risk observed in persons with excess abdominal adiposity. The endocrine impact of adipose tissue on energy homeostasis and inflammation highlights the critical health implications of obesity, particularly abdominal obesity, and the importance of effective prevention and management strategies in clinical practice.

In this study, we characterize the sequences required for the cleavage of prohormones in Xenopus oocytes. We demonstrate that the yeast alpha-factor and the Aplysia egg-laying hormone (ELH) precursors are not cleaved in oocytes following simple pairs of basic residues, such as Lys-Arg, but that the ELH precursor is cleaved following the consensus sequence Arg-Xaa-(Lys/Arg)-Arg. This motif is conserved among precursors that are cleaved in virtually all mammalian cell types. Mutations that generate this sequence in the alpha-factor prohormone also result in efficient processing within oocytes. Cleavage at this consensus sequence may be due to the action of the Xenopus homologues of mammalian furin.

We have combined gene cloning with an assay for prohormone biosynthesis and processing in Xenopus oocytes to identify the genes that encode mammalian prohormone processing enzymes. The coinjection of RNA encoding murine prohormone convertase 1 (mPC1), a mammalian endoprotease, along with proopiomelanocortin RNA into an oocyte results in the appropriate cleavage after paired basic residues in the proopiomelanocortin polyprotein necessary to generate corticotropin. The ability of mPC1 to generate corticotropin, along with the observation that mPC1 is specifically expressed in endocrine and neuronal cells, suggests that the mPC1 gene encodes the endopeptidase responsible for the pathway of proopiomelanocortin cleavage observed in the anterior pituitary.

Background Type 2 diabetes mellitus is a worldwide healthcare problem with major socioeconomic implications. Metabolic surgical procedures have been shown to improve diabetes, but the mechanism of action is poorly understood. The Goto-Kakizaki (GK) rodent is a type 2 diabetic animal model that is ideally situated for studying the effect of surgery on diabetes; however, the operative mortality is high. The aim of this study was to describe the operative technique, improvements in perioperative management, and the technique of micro-positron emission tomography (PET) scanning of the β-cell mass in GK rodents. Methods A total of 53 GK rats were divided into 1 of 3 operative groups: sham, sleeve gastrectomy, and duodenojejunal bypass. A subset of animals underwent micro-PET scanning with [11C]-dihydrotetrabenazine to determine the vesicular monoamine transporter 2 binding index, an indicator of β-cell mass. Results The 30-day mortality in the sham and sleeve gastrectomy rodents was 0; however, 2 sleeve gastrectomy rodents developed enterocutaneous fistula and 1 developed an abscess. In the duodenojejunal bypass group, the initial mortality rate was close to 90%; however, refinements in the surgical technique and perioperative management (fluids, antibiotics, pain control) lowered the mortality rate to 60%. The surgical technique is discussed in detail. [11C]-Dihydrotetrabenazine uptake in the pancreas was demonstrated on micro-PET scanning in the sham and duodenojejunal bypass rodents. Conclusion Intensive medical management in the perioperative period and attention to the operative technique lowered the mortality. [11C]-Dihydrotetrabenazine micro-PET scanning is a feasible method for assessing the β-cell mass in GK rodents and could prove to be an important modality for evaluating β-cell performance in type 2 diabetes.

Gastric distention during meal ingestion activates vagal afferents, which send signals from the stomach to the brain and result in the perception of fullness and satiety. Distention is one of the mechanisms that modulates food intake. We measured regional brain activation during dynamic gastric balloon distention in 18 health subjects using functional magnetic resonance imaging and the blood oxygenation level-dependent (BOLD) responses. The BOLD signal was significantly changed by both inflow and outflow changes in the balloon's volume. For lower balloon volumes, water inflow was associated with activation of sensorimotor cortices and right insula. The larger volume condition additionally activated left posterior amygdala, left posterior insula and the left precuneus. The response in the left amygdala and insula was negatively associated with changes in self-reports of fullness and positively with changes in plasma ghrelin concentration, whereas those in the right amygdala and insula were negatively associated with the subject's body mass index. The widespread activation induced by gastric distention corroborates the influence of vagal afferents on cortical and subcortical brain activity. These findings provide evidence that the left amygdala and insula process interoceptive signals of fullness produced by gastric distention involved in the controls of food intake.

9572 Background: Weight loss among overweight and obese breast and colorectal cancer survivors is hypothesized to be associated with improved disease-free survival. Phase III trials are needed to t...

The hypothalamic melanocortin system regulates feeding in part through interaction of the appetite stimulating peptide, agouti-related protein (AGRP), and the anorectic peptide, alpha-melanocyte stimulating hormone, a peptide derived from the pro-opiomelanocortin (POMC) polyprotein. Central administration of AGRP induces hyperphagia and increased gain in body weight in rodents, but may also exert metabolic effects even when hyperphagia is prevented. In the present studies, the effects of AGRP on hypothalamic neuropeptide gene expression and metabolism were examined in the rat. Central administration of AGRP for 3- and 7-day periods resulted in hyperphagia, increased body weight and increased plasma leptin and insulin concentrations compared to saline-injected controls. Hypothalamic concentrations of Pomc mRNA were also increased by 27% and 44% (in 3- and 7-day experiments, respectively). The hypothalamic concentration of Agrp mRNA was unchanged after 3 days, but was significantly decreased by 33% after 7 days of AGRP infusion. To determine if these changes were dependent upon AGRP-induced hyperphagia, pair-fed rats with restricted food intake receiving central administration of AGRP were also studied. In the absence of hyperphagia, intracerebralventricular administration of AGRP caused significant increases in plasma leptin and insulin concentrations (two-fold and 1.5-fold, respectively) and fat pad mass. A significant increase in hypothalamic Pomc mRNA concentrations was not detected in pair-fed rats. In contrast, Agrp mRNA concentrations remained suppressed by 45% in the pair-fed group after 7 days of AGRP infusion despite equal body weight compared to saline controls. The ratio of hypothalamic Pomc to Agrp mRNA was elevated two-fold in ad libitum and pair-fed AGRP-injected rats, which is consistent with increased stimulation of central melanocortin signalling pathways. Thus, central administration of AGRP exerts changes in hypothalamic neuropeptide gene expression and metabolic effects that are independent of the effects on food intake and body weight.

Importance Controlling glycemia, blood pressure, and cholesterol is important for patients with diabetes. How best to achieve this goal is unknown. Objective To compare Roux-en-Y gastric bypass with lifestyle and intensive medical management to achieve control of comorbid risk factors. Design, Setting, and Participants A 12-month, 2-group unblinded randomized trial at 4 teaching hospitals in the United States and Taiwan involving 120 participants who had a hemoglobin A 1c (HbA 1c ) level of 8.0% or higher, body mass index (BMI) between 30.0 and 39.9, C peptide level of more than 1.0 ng/mL, and type 2 diabetes for at least 6 months. The study began in April 2008. Interventions Lifestyle-intensive medical management intervention and Roux-en-Y gastric bypass surgery. Medications for hyperglycemia, hypertension, and dyslipidemia were prescribed according to protocol and surgical techniques that were standardized. Main Outcomes and Measures Composite goal of HbA 1c less than 7.0%, low-density lipoprotein cholesterol less than 100 mg/dL, and systolic blood pressure less than 130 mm Hg. Results All 120 patients received the intensive lifestyle-medical management protocol and 60 were randomly assigned to undergo Roux-en-Y gastric bypass. After 12-months, 28 participants (49%; 95% CI, 36%-63%) in the gastric bypass group and 11 (19%; 95% CI, 10%-32%) in the lifestyle-medical management group achieved the primary end points (odds ratio [OR], 4.8; 95% CI, 1.9-11.7). Participants in the gastric bypass group required 3.0 fewer medications (mean, 1.7 vs 4.8; 95% CI for the difference, 2.3-3.6) and lost 26.1% vs 7.9% of their initial body weigh compared with the lifestyle-medical management group (difference, 17.5%; 95% CI, 14.2%-20.7%). Regression analyses indicated that achieving the composite end point was primarily attributable to weight loss. There were 22 serious adverse events in the gastric bypass group, including 1 cardiovascular event, and 15 in the lifestyle-medical management group. There were 4 perioperative complications and 6 late postoperative complications. The gastric bypass group experienced more nutritional deficiency than the lifestyle-medical management group. Conclusions and Relevance In mild to moderately obese patients with type 2 diabetes, adding gastric bypass surgery to lifestyle and medical management was associated with a greater likelihood of achieving the composite goal. Potential benefits of adding gastric bypass surgery to the best lifestyle and medical management strategies of diabetes must be weighed against the risk of serious adverse events. Trial Registration clinicaltrials.gov Identifier: NCT00641251

Background: Bariatric procedures such as laparoscopic adjustable gastric banding (LAGB) can markedly decrease body adiposity in severely obese adolescents, but relatively little is known about the short-term effects of such procedures on meal-related hormonal response. Methods: Participants completed a fixed size breakfast meal and fasting concentrations of appetitive hormones (leptin, insulin/glucose, ghrelin, PYY) were measured. PYY, ghrelin, and visual analog scale (VAS) ratings of fullness, hunger, nausea, and desire to eat were assessed immediately before the meal and 15, 30, 60, and 90 minutes afterwards. Results: A total of 10 normal-weight controls (age: 15.4±2.0 years, BMI: 21.3±1.7 kg/m2; n=5 female) and 21 severely obese (age: 16.1±1.0 years, BMI: 46.4±6.6 kg/m2; n=18 females) adolescents were studied pre-LAGB. Eleven of the obese adolescents were studied again 122.6±17.8 days post-LAGB (BMI 40.9±7.8 kg/m2, mean change in BMI: −3.5±2.5 kg/m2). In comparison to normal-weight controls, surgical candidates had significantly higher fasting insulin and leptin and lower fasting ghrelin. Fasting PYY decreased significantly post-surgery. Meal-related suppression of ghrelin, as measured by area under the curve (AUC), was significantly less in absolute value among pre-operative candidates than among normal weight controls [t(9.65) = 2.90, p = 0.017, d = 1.29], with a trend for a decrease in AUC for candidates pre- to post-LAGB [t(10) = 2.07, p = 0.065, d = 0.811]. No significant differences for AUC for PYY were found between normal-weight controls and surgical candidates, or surgical candidates pre- to post-LAGB. Normal-weight controls and surgical candidates did not differ by AUC for any VAS rating; however, post-LAGB, adolescents reported a significantly greater AUC for nausea [t(10) = − 2.58, p=0.03]. Conclusions: Despite short-term decreases in body mass index post-LAGB, few changes were observed in appetitive hormones prior to or following a standardized breakfast. In addition, subjective ratings of fullness, hunger, nausea, and desire to eat did not differ between surgical candidates and normal-weight controls, but following LAGB, adolescents reported significantly more nausea. Future studies should examine longer-term effects of LAGB on appetitive hormones.

We have cloned four members of the family of subtilisin-like endoproteases expressed in the bag cell neurons of Aplysia and have demonstrated that two of these enzymes are capable of correctly cleaving the egg-laying hormone precursor. The egg-laying hormone precursor undergoes an ordered series of cleavages, such that different peptides are differentially sorted into distinct secretory vesicles. We have used electron microscopic chemistry to demonstrate that at least one processing enzyme is differentially segregated into a class of secretory vesicles containing the bag cell peptides. The segregation of specific endoproteases, along with specific neuropeptides within a given cell type, may ensure appropriate cleavage and prevent inappropriate cleavage of the polyprotein precursors.

The SHAPE (Screened Health Assessment and Pacer Evaluation) trial was a 24 month randomized multicenter placebo-controlled study to determine the efficacy of an implantable gastric stimulator (IGS) for weight loss. This report is an investigator-initiated sub-study at one site designed to assess whether IGS affects plasma levels of ghrelin and peptide YY (PYY). The device was implanted in all subjects but was activated in the Treatment group (n = 7, BMI = 41.5 ± 2.0 kg/m2) and remained inactive in the Control (n = 6, BMI = 39.5 ± 1.7 kg/m2) during the first 12 months. IGS was activated in both groups during months 12–24. Fasting venous blood was drawn at months 0, 12, and 24 and an oral glucose tolerance test (OGTT) was performed at month 12. Although there was no difference in weight loss at 6 months (Control: −6.6 ± 1.5% vs. Treatment: −6.2 ± 1.4%), at 24 months the Control group exhibited weight gain from baseline (+2.2 ± 1.5%) that was significantly different from the weight loss in the Treatment group (−1.9 ± 1.4%; P < 0.05). At 12 months, fasting ghrelin was significantly increased (P < 0.05) in the Treatment group (285 ± 35 to 336 ± 35 pg/ml; weight change, −4.9 ± 1.4%), but not in the Control (211 ± 36 to 208 ± 35 pg/ml; weight change, −3.4 ± 1.5%). No significant change was observed in postprandial suppression of plasma ghrelin or in fasting and postprandial PYY levels. In conclusion, IGS does not prevent the increase in fasting plasma ghrelin levels associated with weight loss. Further studies are needed to determine whether changes in technology can improve weight loss and maintenance, perhaps using gut hormones as biomarkers of possible efficacy.

The purpose of this study is to compare effects of different nations on Roux-en-Y gastric bypass (RYGB) vs. intensive medical management (IMM) in achieving remission of type 2 diabetes mellitus (T2DM). Between April 2008 and December 2011, this randomized, controlled clinical trial was conducted at four teaching hospitals in the United States and Taiwan involving 71 participants with mild obesity (BMI 30–35 kg/m2). Thirty-six of 71 participants were randomly assigned to the RYGB group, and the others were in IMM group. Partial or complete remission of T2DM was defined as blood HbA1c