Increase of the Adiponectin/Leptin Ratio in Patients with Obesity and Type 2 Diabetes after Roux-en-Y Gastric Bypass

Association of Body Weight Time in Target Range With the Risk of Kidney Outcomes in Patients With Overweight/Obesity and Type 2 Diabetes Mellitus

OBJECTIVE

We assessed the relationship of body weight time in target range (TTR) with composite kidney outcome in people with overweight/obesity and type 2 diabetes mellitus (T2DM).

RESEARCH DESIGN AND METHODS

Included in this study were 3,601 participants with baseline estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 from the Look AHEAD (Action for Health in Diabetes) trial. Body weight TTR was defined as the proportion of time during the first 4 years that body weight was within the weight loss target (a weight loss of ≥7% from baseline). The primary outcome was composite kidney outcome, defined as eGFR decline ≥30% from baseline and to a level <60 mL/min/1.73 m2 at follow-up visit, or end-stage kidney disease.

RESULTS

During a median follow-up of 8.0 years, 435 cases of composite kidney outcome were documented. Body weight TTR during the first 4 years was inversely associated with the subsequent risk of composite kidney outcome (per SD increment; adjusted hazard ratio [HR] 0.81; 95% CI 0.70-0.93). Accordingly, the adjusted HRs (95% CI) of composite kidney outcome were 1.00 (reference), 0.73 (0.54-1.00), 0.71 (0.52-0.99), and 0.54 (0.36-0.80) for participants with body weight TTR of 0%, >0% to <29.9%, 29.9% to <69.7%, and 69.7% to <100%, respectively. Similar results were found for a doubling of the urine albumin to creatinine ratio (secondary outcome).

CONCLUSIONS

A higher body weight TTR, with a weight loss target of losing ≥7% of initial weight, was associated with a lower risk of kidney outcomes in participants with overweight/obesity and T2DM.

Dynamic Changes in Adiponectin and Resistin Drive Remission of Cardiometabolic Risk Biomarkers in Individuals with Obesity Following Bariatric Surgery

The remission of obesity-related diseases following bariatric surgery appears to result from the reorganization of metabolic and hormonal pathways involving adipokines. This study aimed to investigate the relationship between changes in body adiposity and serum adipokine levels, as well as the association between variations in adiponectin or resistin levels and cardiometabolic risk blood biomarkers before and after Roux-en-Y gastric bypass. A longitudinal and prospective study was conducted with bariatric surgery patients. Anthropometric, body composition and blood biochemical parameters were measured before and at 2 and 6 months post-surgery. The data were analyzed using ANOVA, Pearson or Spearman correlation, and simple linear regression with a significance level of p < 0.05. Among 36 mostly female patients aged 30 to 39 years, significant reductions in body weight (-26.8%), fat mass (-50%), waist circumference (-18%) and waist-to-height ratio (-22%) were observed post-surgery. Serum adiponectin levels increased (+107%), while resistin (-12.2%), TNF-α (-35%), and PAI-1 (-11.1%) decreased. Glucose, insulin, CRP, cholesterol, LDL-c, triglycerides, and vitamin D also decreased. Waist circumference variation showed a positive correlation with PAI-1 and TNF-α and a negative correlation with adiponectin. The total fat mass showed a positive correlation with PAI-1. Adiponectin variation correlated negatively with glucose, resistin, and CRP but positively with HDL-c. Resistin showed a positive correlation with insulin and CRP. In conclusion, 6 months post-bariatric surgery, reducing abdominal adiposity had a more significant impact on serum adipokine levels than total fat mass. Adiponectin increase and resistin decrease acted as endocrine mediators driving the remission of cardiometabolic risk biomarkers in individuals with obesity following Roux-en-Y gastric bypass.

Variation of modulation and expression of biomarkers associated with inflammation in bariatric surgery patients: A systematic review and meta-analysis

BACKGROUND

Bariatric surgery is an effective intervention that causes a series of metabolic changes related to inflammatory processes; however, the variation of biomarkers related to these processes is not entirely understood. Our objective was to investigate the variation of modulation and expression of biomarkers associated with inflammation in patients who underwent bariatric surgery.

METHODS

We searched the MEDLINE (via PubMed), EMBASE (via Elsevier), Cochrane Central Register of Controlled Trials, Latin American and Caribbean Literature on Health Sciences (via virtual health library), Cumulative Index to Nursing and Allied Health Literature (via EBSCO), Web of Science core collection, and Scopus (via Elsevier) databases, and the gray literature was examined from inception to January 2022. Three pairs of reviewers performed data screening, extraction, and quality assessment independently. Meta-analysis with random effects models was used for general, subgroup, and sensitivity analyses. The I2 statistic was used to assess heterogeneity between studies.

RESULTS

In total, 96 articles were included in this systematic review; of these, 87 studies met the criteria for the meta-analysis, involving 3,533 participants. Five biomarkers were included in the meta-analysis (tumor necrosis factor alpha; interleukin 6; leptin; interleukin 1 beta, and lipopolysaccharides). Only leptin showed a significant decrease in the first month after surgery (mean difference -20.71; [95% confidence interval: -28.10 to -13.32, P < .0001; I2 = 66.7%), with moderate heterogeneity. The 12 months after surgery showed a significant decrease in tumor necrosis factor alpha (mean difference -0.89; [95% confidence interval: -1.37 to -0.42], P = .0002; I2 = 94.7%), interleukin 6 (mean difference -1.62; [95% confidence interval: -1.95 to -1.29], P < .0001; I2 = 94.9%), leptin (mean difference -28.63; [95% confidence interval: -34.02 to -23.25], P < .0001; I2 = 92.7%), and interleukin 1 beta (mean difference -2.46; [95% confidence interval: -4.23 to -0.68], P = .006; I2 = 98.3%), all with high heterogeneity. The type of surgery did not show significant differences for the biomarkers at the first month and 12 months, and the results have not changed with high-quality studies. In the 12-month measurement, variations in tumor necrosis factor alpha and leptin were associated with body mass index.

CONCLUSION

The findings of this meta-analysis suggest that Roux-en-Y gastric bypass and sleeve gastrectomy bariatric surgeries are associated with a significant reduction in leptin at 1 month after bariatric surgical intervention and tumor necrosis factor alpha, leptin, and interleukin 1 beta after 12 months.

Clinical improvement may not reflect metabolic homeostasis normalization in subjects with and without Roux-En-Y bariatric surgery after 12 years: comparison of surgical subjects to a lean cohort

Background

A 12-year study comparing clinical outcomes following Roux-en-Y bariatric surgery showed long-term weight loss with remission/prevention of type-2-diabetes (T2D), hypertension and dyslipidemia. However, it is unknown whether the underlying homeostatic metabolic processes involving hepatokines, adipokines and myokines also normalize. Using this 12-year study, we determined whether metabolic indices improved in post-surgical (BMI:34.4kg/m2) versus non-surgical comparator-subjects-with-obesity (BMI:43.8kg/m2) at 12-year follow-up (both cohorts with baseline diabetes), and if post-surgical subjects normalized their metabolic processes to those of a normal-weight cohort without diabetes.

Methods

Cross-sectional design. Plasma from a cohort of Roux-en-Y bariatric surgery (n=50) and non-surgery (n=76) comparator-subjects-with-obesity (both cohorts at 12-year follow-up) plus a normal-weight cohort (n=39) was assayed by Luminex immunoassay or ELISA for hepatokines [angiopoietin-like proteins-(ANGPTL3; ANGPTL4; ANGPTL6); fibroblast growth factors-(FGF19; FGF21; FGF23)]; adipokines [adipsin; adiponectin; FGF19] and myonectin.

Results

After age and gender adjustment, surgery versus comparator-subjects-with-obesity had lower BMI (34.4 ± 1.0 vs 43.8 ± 0.9kg/m2; p<0.0001), HbA1c (6.2 ± 0.3 vs 7.7 ± 0.2%; p<0.0001), insulin resistance (HOMA-IR, 2.0 ± 1.5 vs 10.8 ± 1.4; p<0.0001) fat mass (45.6 ± 2.2 vs 60.0 ± 2.0; p<0.0001), HDL-C (55.4 ± 2.6 vs 42.6 ± 2.3mg/dL; p<0.0001), triglycerides (130 ± 14 vs 187 ± 12mg/dL; p<0.0001) and higher adiponectin (25.9 ± 2.3 vs 15.7 ± 2.0µg/ml; p<0.001); Adipsin, ANGPTL3, ANGPTL4, ANGPTL6, FGF19, FGF21, FGF23 and myonectin did not differ. Surgery versus normal-weight group: higher ANGPTL4 (156 ± 6 vs 119 ± 7ng/mL; p<0.0001), higher FGF23 (96.4 ± 10.1 vs 50.9 ± 11.5pg/mL; p=0.007) and lower myonectin (744 ± 55 vs 969 ± 66ng/mL; p=0.002); adiponectin, adipsin ANGPTL3, ANGPTL6, FGF19, FGF21 did not differ. Non-surgery comparator-subjects-with-obesity versus normal-weight group: higher adipsin (1859 ± 94 vs 1314 ± 133ng/mL; p=0.0001), higher FGF23 (84.6 ± 8.5 vs 50.9 ± 11.5pg/mL; p<0.0001) and higher ANGPTL4 (171 ± 5 vs 119 ± 7ng/mL; p<0.0001); adiponectin ANGPTL3, ANGPTL6, FGF19, FGF21 and myonectin did not differ.

Conclusion

Bariatric surgery markedly improved anthropometric and metabolic features versus comparator-subjects-with-obesity at 12-year follow-up, indicating benefit of weight loss. However, despite weight loss, these patients still had class-1 obesity, as reflected in the adipokine, hepatokine and myokine markers of body homeostasis that did not completely normalize to indicative values of normal-weight subjects, suggesting either that this is the new normal for these patients or that weight loss to a BMI<25kg/m2 is needed for normalization of these parameters.

Roux-en-Y Gastric Bypass Improves Adiponectin to Leptin Ratio and Inflammatory Profile in Severely Obese Women with and without Metabolic Syndrome: A Randomized Controlled Trial

Obesity is a troubling public health problem as it increases risks of sleep disorders, respiratory complications, systemic arterial hypertension, cardiovascular diseases, type 2 diabetes mellitus, and metabolic syndrome (MetS). As a measure to counteract comorbidities associated with severe obesity, bariatric surgery stands out. This study aimed to investigate the adiponectin/leptin ratio in women with severe obesity with and without MetS who had undergone Roux-en-Y gastric bypass (RYGB) and to characterize the biochemical, glucose, and inflammatory parameters of blood in women with severe obesity before and after RYGB. Were enrolled females with severe obesity undergoing RYGP with MetS (n = 11) and without (n = 39). Anthropometric data and circulating levels of glucose, total cholesterol, high-density lipoprotein (HDL), non-HDL total cholesterol, low-density lipoprotein (LDL), adiponectin, and leptin were assessed before and 6 months after RYGB. Significant reductions in weight, body mass index, and glucose, total cholesterol, LDL, and leptin were observed after surgery, with higher levels of HDL, adiponectin, and adiponectin/leptin ratio being observed after surgery compared to the preoperative values of those. This study demonstrated that weight loss induced by RYGB in patients with severe obesity with or without MetS improved biochemical and systemic inflammatory parameters, particularly the adiponectin/leptin ratio.

Pharmacological antagonism of receptor for advanced glycation end products signaling promotes thermogenesis, healthful body mass and composition, and metabolism in mice

OBJECTIVE

Optimal body mass and composition as well as metabolic fitness require tightly regulated and interconnected mechanisms across tissues. Disturbances in these regulatory networks tip the balance between metabolic health versus overweight and obesity and their complications. The authors previously demonstrated roles for the receptor for advanced glycation end products (RAGE) in obesity, as global- or adipocyte-specific deletion of Ager (the gene encoding RAGE) protected mice from high-fat diet-induced obesity and metabolic dysfunction.

METHODS

To explore translational strategies evoked by these observations, a small molecule antagonist of RAGE signaling, RAGE229, was administered to lean mice and mice with obesity undergoing diet-induced weight loss. Body mass and composition and whole body and adipose tissue metabolism were examined.

RESULTS

This study demonstrates that antagonism of RAGE signaling reduced body mass and adiposity and improved glucose, insulin, and lipid metabolism in lean male and female mice and in male mice with obesity undergoing weight loss. In adipose tissue and in human and mouse adipocytes, RAGE229 enhanced phosphorylation of protein kinase A substrates, which augmented lipolysis, mitochondrial function, and thermogenic programs.

CONCLUSIONS

Pharmacological antagonism of RAGE signaling is a potent strategy to optimize healthful body mass and composition and metabolic fitness.

Adipose tissue dysfunction serum markers are associated with high density lipoprotein size and glycation in the early stages of type 2 diabetes

BACKGROUND

High-density lipoproteins (HDLs) have antiatherogenic properties related to their chemical structure. Adipose tissue (AT) influences HDL reverse cholesterol transport and plasma HDL cholesterol levels. However, whether AT dysfunction affects HDL subpopulations and their glycation in early type 2 diabetes (T2D) is still unknown.

OBJECTIVE

To investigate the association of inflammation and AT dysfunction serum markers with the size and glycation of HDLs in normoglycemic, prediabetes, and T2D subjects.

METHODS

We assessed HDL particle size and advanced glycation end-product (AGE) content in HDLs isolated from normoglycemic (n = 17), prediabetes (n = 17), and recently T2D-diagnosed (n = 18) subjects. Insulin, adiponectin, and plasminogen activator inhibitor 1 (PAI-1) were determined using the Bio-Rad Multiplex Platform, and free fatty acids (FFAs) and high sensitivity C-reactive protein (hs-CRP) were determined by standard procedures. The AT insulin resistance (ATIR) index and ATIR/adiponectin and adiponectin/leptin ratios were calculated.

RESULTS

HDL was progressively smaller (nm) and enriched with AGE (mg-BSA-AGE/mg protein) according to the glucose categories: 8.49 and 7.5 in normoglycemic subjects, 8.44 and 12.4 in prediabetic subjects, and 8.32 and 14.3 in T2D subjects (P = 0.033 and P = 0.009 for size and AGE, respectively). In multivariable regression analysis, the ATIR/adiponectin ratio was inversely associated with HDL size (β = -0.257, P = 0.046), and the ATIR ratio was directly associated with HDL glycation (β = 0.387, P = 0.036). In contrast, adiponectin and the adiponectin/leptin ratio were not associated with alterations in HDL particles. Furthermore, HDL size was associated with resistin (β = -0.348, P = 0.007) and PAI-1 (β = -0.324, P = 0.004). HDL and AGE were related to insulin concentrations (β = 0.458, P = 0.015). Analyses were adjusted for age, sex, body mass index, triglycerides, and HDL-cholesterol.

CONCLUSION

HDL size was significantly associated with the ATIR/adiponectin ratio and inflammation, whereas glycation was more strongly related to the ATIR index. These findings have important implications for the management and prevention of cardiovascular disease in T2D patients.

Sex- and Age-Dependent Changes in the Adiponectin/Leptin Ratio in Experimental Diet-Induced Obesity in Mice

Biological sex and aging impact obesity development and type 2 diabetes, changing the secretion of leptin and adiponectin. The balance between these factors has been propounded as a reliable biomarker of adipose tissue dysfunction. Our proposal was to study sexual differences and aging on the adiponectin/leptin (Adpn/Lep) ratio in order to acquire a broader view of the impact of consuming an high-fat diet (HFD) on energy metabolism according to sex and age. Male and female C57BL/6J mice were fed a normal chow diet or an HFD for 12 or 32 weeks (n = 7−10 per group) and evolution of body weight, food intake and metabolic profile were registered. The HFD triggered an increase in body weight (p < 0.001), body weight gain (p < 0.01) and adiposity index (p < 0.01) in both sexes at 32 weeks of age, but female mice fed the HFD exhibited these changes to a significantly lower extent than males. Aged female mice showed an increase (p < 0.01) in the Adpn/Lep ratio, which was negatively correlated with body weight gain, changes in different fat depots and insulin resistance. Females were more metabolically protected from obesity development and its related comorbidities than males regardless of age, making the Adpn/Lep ratio a relevant factor for body composition and glucose metabolism.

Contribution of markers of adiposopathy and adipose cell size in predicting insulin resistance in women of varying age and adiposity

Adipose tissue (AT) dysfunctions, such as adipocyte hypertrophy, macrophage infiltration and secretory adiposopathy (low plasma adiponectin/leptin, A/L, ratio), associate with metabolic disorders. However, no study has compared the relative contribution of these markers to cardiometabolic risk in women of varying age and adiposity. Body composition, regional AT distribution, lipid-lipoprotein profile, glucose homeostasis and plasma A and L levels were determined in 67 women (age: 40-62 years; BMI: 17-41 kg/m²). Expression of macrophage infiltration marker CD68 and adipocyte size were measured from subcutaneous abdominal (SCABD) and omental (OME) fat. AT dysfunction markers correlated with most lipid-lipoprotein levels. The A/L ratio was negatively associated with fasting insulinemia and HOMA-IR, while SCABD or OME adipocyte size and SCABD CD68 expression were positively related to these variables. Combination of tertiles of largest adipocyte size and lowest A/L ratio showed the highest HOMA-IR. Multiple regression analyses including these markers and TAG levels revealed that the A/L ratio was the only predictor of fasting insulinemia and HOMA-IR. The contribution of the A/L ratio was superseded by adipose cell size in the model where the latter replaced TAGs. Finally, leptinemia was a better predictor of IR than adipocyte size and the A/L ratio in our participants sample.

Liraglutide + PYY3-36 Combination Therapy Mimics Effects of Roux-en-Y Bypass on Early NAFLD Whilst Lacking-Behind in Metabolic Improvements

Background: Treatment options for NAFLD are still limited. Bariatric surgery, such as Roux-en-Y gastric bypass (RYGB), has been shown to improve metabolic and histologic markers of NAFLD. Glucagon-like-peptide-1 (GLP-1) analogues lead to improvements in phase 2 clinical trials. We directly compared the effects of RYGB with a treatment using liraglutide and/or peptide tyrosine tyrosine 3-36 (PYY_3-36) in a rat model for early NAFLD. Methods: Obese male Wistar rats (high-fat diet (HFD)-induced) were randomized into the following treatment groups: RYGB, sham-operation (sham), liraglutide (0.4 mg/kg/day), PYY_3-36 (0.1 mg/kg/day), liraglutide+PYY_3-36, and saline. After an observation period of 4 weeks, liver samples were histologically evaluated, ELISAs and RNA sequencing + RT-qPCRs were performed. Results: RYGB and liraglutide+PYY_3-36 induced a similar body weight loss and, compared to sham/saline, marked histological improvements with significantly less steatosis. However, only RYGB induced significant metabolic improvements (e.g., adiponectin/leptin ratio 18.8 ± 11.8 vs. 2.4 ± 1.2 in liraglutide+PYY_3-36- or 1.4 ± 0.9 in sham-treated rats). Furthermore, RNA sequencing revealed a high number of differentially regulated genes in RYGB treated animals only. Conclusions: The combination therapy of liraglutide+PYY_3-36 partly mimics the positive effects of RYGB on weight reduction and on hepatic steatosis, while its effects on metabolic function lack behind RYGB.

Novel Insight into the Mechanism of Metabolic Surgery Causing the Diversity in Glycemic Status in Type 2 Diabetes

Metabolic surgery results in diverse glycemic status in patients with type 2 diabetes (T2D), including hyperglycemia without remission, significant amelioration of hyperglycemia with partial remission, complete restoration of euglycemia, or with prolonged remission, hyperglycemia recurrence in relapses after remission, or post-bariatric hypoglycemia. Unfortunately, it is not known how metabolic surgery leads to this diverse consequence. Here, we discuss the diversity of glycemic status associated with metabolic surgery and the potential mechanisms of T2D remission. We also highlight the relationship between the change in low-grade inflammation and T2D remission after metabolic surgery. We hypothesize that the level of inflammatory and anti-inflammatory cytokines controls the efficacy of metabolic surgery in patients with T2D. This hypothesis may provide further insight into the mechanism of the beneficial effects of metabolic surgery patients with T2D.

Hashtag bone: detrimental effects on bone contrast with metabolic benefits one and five years after Roux-en-Y gastric bypass

Bone loss is a potential adverse consequence of rapid and sustained weight loss after bariatric surgery. The aim of the present study was to evaluate the bone mass, body fat distribution, and metabolic parameters in women submitted to Roux-en-Y gastric bypass (RYGB). The study included the following three groups: one group of lean women (control [C] group) and two groups of obese women, one evaluated one year (B1) and the other five years (B5) after RYGB. Dual-energy X-ray absorptiometry and magnetic resonance imaging were used to determine bone mineral density (BMD; lumbar spine, total hip, and femoral neck) and abdominal fat content (subcutaneous [SAT] and visceral [VAT] adipose tissues, and intrahepatic lipids [IHL]). The BMD/body mass index ratio was lower in the B5 compared with the C group at all sites. Serum C-terminal telopeptide of type I collagen (CTX) levels were higher in the B1 and B5 groups compared with the C group. Individuals submitted to RYGB showed greater SAT but similar VAT and IHL values compared with those in the C group. However, the B5 group had higher mean parathyroid hormone levels compared with the other two groups. Individuals submitted to RYGB presented increased levels of CTX and low BMD for body weight than those in the C group, suggesting that bone catabolism is a persistent alteration associated with RYGB. In conclusion, the long-lasting metabolic benefits obtained with RYGB in obesity are counterbalanced by a persistent catabolic effect of the procedure on bone and mineral metabolism.

Reduced Th1 response is associated with lower glycolytic activity in activated peripheral blood mononuclear cells after metabolic and bariatric surgery

BACKGROUND

Obesity promotes cellular immunometabolism changes that trigger the activation of macrophages and lymphocytes, leading to systemic inflammation. Activated leukocytes undergo metabolic reprogramming, increasing glycolytic activity.

OBJECTIVE

To examine whether the reduction in the inflammatory state associated with bariatric surgery is associated with decreased glycolytic activity in leukocytes. Setting Single-center, prospective observational study.

METHODS

This study involved 18 patients with obesity undergoing bariatric surgery. All measurements were performed preoperatively and six months postoperatively. Peripheral blood mononuclear cells and plasma were obtained to determine the glycolytic rate and mitochondrial membrane potential as surrogates of the metabolic switching and high-sensitivity C-reactive protein, adipokines, and CD69 expression as inflammatory and activation markers.

RESULTS

Glycolytic activity engaged by CD3/CD28 activation was reduced six months after bariatric surgery, associated with decreased levels of T helper (Th) 1 and Th17 signature cytokines. An overall reduction in inflammatory markers was observed, which correlated with a higher adiponectin/leptin ratio.

CONCLUSIONS

Metabolic and bariatric surgery-induced weight loss leads to reprogramming in T cells' metabolic machinery, resulting in reduced stimulation of glycolysis after activation, which may explain the decrease in systemic inflammation mediated by cytokines such as interferon-γ and interleukin-17A.

Body Composition, Basal Metabolic Rate and Leptin in Long-Term Weight Regain After Roux-en-Y Gastric Bypass Are Similar to Pre-surgical Obesity

PURPOSE

The purpose of this study is to evaluate the relationship between body composition, basal metabolic rate (BMR), and serum concentrations of leptin with long-term weight regain after Roux-en-Y gastric bypass (RYGB) and compare it with obesity before surgery.

MATERIALS AND METHODS

Prospective longitudinal analytical study. Three groups were formed: individuals 60 months post RYGB, with weight regain (G1) and without it (G2), and individuals with obesity who had not undergone bariatric surgery (G3). Body fat (BF), body fat mass (BFM), visceral fat (VF), fat-free mass (FFM), skeletal muscle mass (SMM), and BMR were assessed by octapolar and multi-frequency electrical bioimpedance. Fasting serum concentrations of leptin were measured.

RESULTS

Seventy-two individuals were included, 24 in each group. Higher means of BF, BFM, VF, and leptin levels were observed in G1, when compared to G2 (BF: 47.5 ± 5.6 vs. 32.0 ± 8.0, p < 0.05; FBM: 47.8 ± 11.6 vs. 23.9 ± 7.0, p < 0.05; VF: 156.8 ± 30.2 vs. 96.1 ± 23.8, p < 0.05; leptin: 45,251.2 pg/mL ± 20,071.8 vs. 11,525.7 pg/mL ± 9177.5, p < 0.000). G1 and G2 did not differ in FFM, SMM, and BMR. G1 and G3 were similar according to BF, FFM, BMR, and leptin levels. Body composition, but not leptin, was correlated with %weight regain in G1 (FBM: r = 0.666, p < 0.000; BF: r = 0.428, p = 0.037; VF: r = 0.544, p = 0.006).

CONCLUSION

Long-term weight regain after RYGB is similar to pre-surgical obesity in body composition, BMR, and leptin concentrations, indicating relapse of metabolic and hormonal impairments associated with excessive body fat.

Update on Metabolic Bariatric Surgery for Morbidly Obese Adolescents

Despite worldwide public attention and intense medical efforts, the prevalence of severe morbid obesity in children and adolescents is still rising. Similar to adults, excess adipose tissue triggers multiple immunological and metabolic pathways leading to serious co-morbidities such as impaired glucose tolerance or even type 2 diabetes (T2D), dyslipidemia, arterial hypertension, non-alcoholic fatty liver disease, and hyperuricemia. The management of severe childhood obesity requires a life-long multidisciplinary approach with a combination of lifestyle changes, nutrition, and medications. Standardized life-style intervention programs remain the first-line treatment for morbid obese children and adolescents, but unfortunately reveal limited long-term success. In such cases, metabolic bariatric surgery (MBS) has evolved from being a controversial issue to being included in distinct recommendations. According to the American Society for Metabolic and Bariatric Surgery (ASMBS) Pediatric Committee, indications for bariatric surgery in adolescence must follow very strict criteria. Adolescents with class II obesity (BMI > 120% of the 95th percentile) and a diagnosed co-morbidity or with class III obesity (BMI ≥ 140% of the 95th percentile) should be considered for MBS. These interventions represent high-risk operations, and adolescents should be treated in specialized, multidisciplinary high-volume obesity centers with long-term follow-up programs. The Roux-en-Y gastric bypass (RYGB) remains the gold standard of all malabsorptive procedures. Laparoscopic sleeve gastrectomy (LSG), which the authors pioneered as a stand-alone procedure in morbidly obese adolescents in 2008, has become the most commonly performed operation in morbidly obese adolescents at present. Recent literature proves that MBS is safe and effective in morbidly obese adolescents. Mid-term data have revealed significant improvement or even resolution of major co-morbidities. Thus, MBS for the treatment of morbidly obese adolescents has evolved from being a controversial issue to being included in distinct recommendations by several medical societies as a therapeutic strategy to reduce severe co-morbidities potentially causing end-organ damage in adulthood.

Leptin Receptors Are Not Required for Roux-en-Y Gastric Bypass Surgery to Normalize Energy and Glucose Homeostasis in Rats

Sensitization to the adipokine leptin is a promising therapeutic strategy against obesity and its comorbidities and has been proposed to contribute to the lasting metabolic benefits of Roux-en-Y gastric bypass (RYGB) surgery. We formally tested this idea using Zucker fatty fa/fa rats as an established genetic model of obesity, glucose intolerance, and fatty liver due to leptin receptor deficiency. We show that the changes in body weight in these rats following RYGB largely overlaps with that of diet-induced obese Wistar rats with intact leptin receptors. Further, food intake and oral glucose tolerance were normalized in RYGB-treated Zucker fatty fa/fa rats to the levels of lean Zucker fatty fa/+ controls, in association with increased glucagon-like peptide 1 (GLP-1) and insulin release. In contrast, while fatty liver was also normalized in RYGB-treated Zucker fatty fa/fa rats, their circulating levels of the liver enzyme alanine aminotransferase (ALT) remained elevated at the level of obese Zucker fatty fa/fa controls. These findings suggest that the leptin system is not required for the normalization of energy and glucose homeostasis associated with RYGB, but that its potential contribution to the improvements in liver health postoperatively merits further investigation.

Effect of Weight Loss by Low-Calorie Diet on Cardiovascular Health in Type 2 Diabetes: An Interventional Cohort Study

Cardiovascular disease (CVD) remains a major problem for people with type 2 diabetes (T2DM), and the leading cause of death worldwide. We aimed to determine cardiovascular benefits of weight loss with or without remission of diabetes, and to assess utility of plasma biomarkers. 29 people with T2DM were studied at baseline and after dietary weight loss. Change in plasma adipokines and lipid related markers was examined in relation to weight loss, diabetes remission, 10-year cardiovascular risk (QRISK), and duration of diabetes. QRISK decreased markedly after weight loss (18.9 ± 2.2 to 11.2 ± 1.6%, p < 0.0001) in both responders and non-responders, but non-responders remained at higher risk (15.0 ± 2.0 vs. 5.8 ± 1.6%, p < 0.0001). At baseline, plasma GDF-15 was higher in longer diabetes duration (1.19 ± 0.14 vs. 0.82 ± 0.09 ng/mL, p = 0.034), as was the QRISK (22.8 ± 2.6 vs. 15.3 ± 3.4%, p = 0.031). Leptin, GDF-15 and FGF-21 decreased whereases adiponectin increased after weight loss in responders and non-responders. However, the level of FGF-21 remained higher in non-responders (0.58 [0.28–0.71] vs. 0.25 [0.15–0.42] ng/mL, p = 0.007). QRISK change correlated with change in plasma VLDL1-TG (r = 0.489, p = 0.007). There was a positive correlation between rise in HDL cholesterol and the decrease in leptin (r = 0.57, p = 0.001), or rise in adiponectin (r = 0.58, p = 0.001) levels. In conclusion, weight loss markedly decreases cardiometabolic risk particularly when remission of diabetes is achieved. Leptin, adiponectin, GDF-15 and FGF-21 changes were related to weight loss not remission of diabetes. Normalization of 10-year cardiovascular risk and heart age is possible after substantial dietary weight loss and remission of T2DM.

RYGB Is More Effective than VSG at Protecting Mice from Prolonged High-Fat Diet Exposure: An Occasion to Roll Up Our Sleeves?

PURPOSE

Understanding the effects of Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) on adipose tissue physiology is important for the treatment of obesity-related metabolic disorders. By using robust mouse models of bariatric surgery that closely resemble those performed in humans, we can compare the effects of RYGB and VSG on adipose physiology in the absence of post-operative confounds such as diet and lifestyle changes.

MATERIALS AND METHODS

RYGB and VSG were compared using a diet-induced mouse model of obesity. High-fat diet (HFD) was administered post-operatively and changes to white and brown adipose tissue were evaluated, along with alterations to weight, glucose homeostasis, dyslipidemia, and insulin sensitivity.

RESULTS

After prolonged exposure to high-fat diet post-operatively, RYGB was effective in achieving sustained weight loss, while VSG unexpectedly accelerated weight gain rates. The resolution of obesity-related comorbidities such as glucose and insulin intolerance, dyslipidemia, and insulin sensitivity was improved after RYGB, but not for VSG. In RYGB, there were improvements to the function and health of white adipose tissue, enhanced brown adipose metabolism, and the browning of subcutaneous white adipose tissue, with no comparable changes seen for these factors after VSG. Some markers of systemic inflammation improved after both RYGB and VSG.

CONCLUSION

There are significantly different effects between RYGB and VSG when HFD is administered post-operatively and robust mouse models of bariatric surgery are used. RYGB resulted in lasting physiological and metabolic changes but VSG showed little difference from that of its sham-operated, DIO counterpart.

The leptin to adiponectin ratio (LAR) is reduced by sleeve gastrectomy in adults with severe obesity: a prospective cohort study

Bariatric surgery is known to reduce leptin and increase adiponectin levels, but the influence of sleeve gastrectomy on the leptin: adiponectin ratio (LAR), a measure of insulin sensitivity and cardiovascular risk, has not previously been described. We sought to determine the influence of sleeve gastrectomy on LAR in adults with severe obesity.In a single centre prospective cohort study of adults undergoing laparoscopic sleeve gastrectomy over a four-month period in our unit, we measured LAR preoperatively and 12 months after surgery. Of 22 patients undergoing sleeve gastrectomy, 17 (12 females, 12 with type 2 diabetes) had follow-up LAR measured at 12.1 ± 1 months. Mean body weight decreased from 130.6 ± 30.8 kg to 97.6 ± 21.6 kg, body mass index (BMI) from 46.9 ± 7.8 to 35.3 ± 7.2 kg m^-2 and excess body weight from 87.5 ± 31.3 to 41.3 ± 28.8% (all p < 0.001). The reduction in leptin from 40.7 ± 24.9 to 30.9 ± 30.5 ng/ml was not significant (p = 0.11), but adiponectin increased from 4.49 ± 1.6 to 8.93 ± 6.36 µg/ml (p = 0.005) and LAR decreased from 8.89 ± 4.8 to 5.26 ± 6.52 ng/µg (p = 0.001), equivalent to a 70.9% increase in insulin sensitivity. The correlation with the amount of weight lost was stronger for LAR than it was for leptin or adiponectin alone. In this single-centre, interventional prospective cohort, patients undergoing laparoscopic sleeve gastrectomy had a substantial reduction in their LAR after 12 months which was proportional to the amount of weight lost. This may indicate an improvement in insulin sensitivity and a reduction in cardiovascular risk.

Influence of magnitude of weight loss on Adipo/lep ratio in adolescents with obesity undergoing multicomponent therapy

BACKGROUND AND AIMS

The expansion of adipose tissue increases leptin secretion associated with a reduction of adiponectin concentration, which negatively affects health of adolescents with obesity. This study aims to investigate the effects of non-intensive interdisciplinary therapy on cardiometabolic parameters including leptin, adiponectin and adiponectin/leptin ratio as a dependent manner on its magnitude of weight loss reduction.

METHODS AND RESULTS

Thirty-eight adolescents (14-19 y.o) were enrolled in an interdisciplinary therapy for 20 weeks. Body composition, biochemical parameters, leptin and adiponectin were measured at baseline and after therapy. The adolescents were divided into two groups according to the magnitude of total weight loss, less than 5% (<5%-n = 18) or greater than or equal to 5% (≥5%-n = 20). Leptin decreased in whole group after therapy, while adiponectin, and adiponectin/leptin ratio increased. Additionally, body composition was improved. Only the group who lost ≥5% of body weight could reduce the inflammatory state.

CONCLUSION

The interdisciplinary therapy contributes to improve cardiometabolic parameters that could be involved on inflammation in adolescents with obesity, this improvement occurred mainly when the weight loss is ≥5% of body weight. It could be a target for control the inflammatory process related to obesity in adolescents.

Influence of inflammation and adipocyte biochemical markers on the components of metabolic syndrome

Metabolic syndrome is associated with increased risk of cardiovascular disease. This study investigated the correlation between adipocyte and inflammation biomarkers, and metabolic syndrome and its components. The study included 80 patients with normal body-mass index and 80 obese patients. The groups were assessed for serum values of adiponectin, leptin and highly sensitive C reactive protein (hsCRP), the homeostatic model assessment of insulin resistance (HOMA-IR), as well as the influence of these biochemical markers on the prevalence of metabolic syndrome and its components. Leptin, HOMA-IR and hsCRP had statistically significant (P<0.01) higher values in the group of obese subjects, while adiponectin had statistically significant (P<0.01) lower values. The prevalence of metabolic syndrome was 35% in the obese group and 5% in the normal weight group. Adiponectin and HOMA-IR were the variables significantly associated with metabolic syndrome (P<0.01), adiponectin/HOMA-IR ratio and leptin/adiponectin ratio were also associated with metabolic syndrome (P<0.01). No relationship was found between metabolic syndrome and hsCRP. Adiponectin and adiponectin/HOMA-IR were associated with all the components of metabolic syndrome and they can be useful to identify patients with high risk of diabetes mellitus and cardiovascular disease.