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Metabolic syndrome (MetS) is highly prevalent in children and adolescents with obesity and places them at an increased risk of cardiovascular-related diseases. However, the associations between objectively measured movement-related behaviors and MetS diagnosis remain unexplored in youths with obesity. The aim was to compare profiles of sedentary (SED) time (more sedentary, SED+ vs. less sedentary, SED−), moderate to vigorous physical activity (MVPA) time (more active, MVPA+ vs. less active, MVPA−) and combinations of behaviors (SED−/MVPA+, SED−/MVPA−, SED+/MVPA+, SED+/MVPA−) regarding the MetS diagnosis. One hundred and thirty-four adolescents with obesity (13.4 ± 2.2 years) underwent 24 h/7 day accelerometry, waist circumference (WC), blood pressure (BP), high-density lipoprotein-cholesterol (HDL-c), triglycerides (TG) and insulin-resistance (IR) assessments. Cumulative cardiometabolic risk was assessed by using (i) MetS status (usual dichotomic definition) and (ii) cardiometabolic risk z-score (MetScore, mean of standardized WC, BP, IR, TG and inverted HDL-c). SED− vs. SED+ and MVPA+ vs. MVPA− had lower MetS (p < 0.01 and p < 0.001) and MetScore (p < 0.001). SED−/MVPA+ had the lowest risk. While SED and MVPA times were lower in SED−/MVPA− vs. SED+/MVPA+ (p < 0.001), MetScore was lower in SED−/MVPA− independently of body mass index (BMI) (p < 0.05). MVPA, but not SED, time was independently associated with MetS diagnosis (p < 0.05). Both MVPA (p < 0.01) and SED times (p < 0.05) were associated with MetScore independently of each other. A higher MVPA and lower SED time are associated with lower cumulative cardiometabolic risk.

The protein tyrosine kinase inhibitor imatinib is used in the treatment of various malignancies but may also promote beneficial effects in the treatment of diabetes. The aim of the present investigation was to characterize the mechanisms by which imatinib protects insulin producing cells. Treatment of non-obese diabetic (NOD) mice with imatinib resulted in increased beta-cell AMP-activated kinase (AMPK) phosphorylation. Imatinib activated AMPK also in vitro, resulting in decreased ribosomal protein S6 phosphorylation and protection against islet amyloid polypeptide (IAPP)-aggregation, thioredoxin interacting protein (TXNIP) up-regulation and beta-cell death. 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR) mimicked and compound C counteracted the effect of imatinib on beta-cell survival. Imatinib-induced AMPK activation was preceded by reduced glucose/pyruvate-dependent respiration, increased glycolysis rates, and a lowered ATP/AMP ratio. Imatinib augmented the fractional oxidation of fatty acids/malate, possibly via a direct interaction with the beta-oxidation enzyme enoyl coenzyme A hydratase, short chain, 1, mitochondrial (ECHS1). In non-beta cells, imatinib reduced respiratory chain complex I and II-mediated respiration and acyl-CoA carboxylase (ACC) phosphorylation, suggesting that mitochondrial effects of imatinib are not beta-cell specific. In conclusion, tyrosine kinase inhibitors modestly inhibit mitochondrial respiration, leading to AMPK activation and TXNIP down-regulation, which in turn protects against beta-cell death.

Neuroblastoma, the most common solid tumor in children, is characterized by amplification of the MYCN proto-oncogene, a high-risk aggressive clinical marker associated with treatment failure. MYCN plays an important role in cell growth, proliferation, metabolism, and chemoresistance. Here, we show for the first time that in neuroblastoma, iron chelator VLX600 inhibits mitochondrial respiration, decreases expression levels of MYCN/LMO1, and induces an efficient cell death regardless of MYCN status in both 2D and 3D culture conditions. Moreover, insufficient induction of autophagy was observed in cells treated with VLX600, which is essential as a protective response in the event of ATP synthesis disruption. Further inhibition of glucose uptake using DRB18, a pan-GLUT (glucose transporter) inhibitor, synergized the effect of VLX600 and no significant cell death was found in immortalized epithelial cells under this combination treatment. Our results demonstrate that inhibition of mitochondrial respiration by iron chelator VLX600 accompanied by autophagy deficiency promotes sensitivity of neuroblastoma cells in a nutrition-restricted microenvironment regardless of MYCN status, indicating that MYCN expression level is an essential clinical marker but might not be a necessary target for the treatment of neuroblastoma which warrants further investigation. VLX600 has been studied in Phase I clinical trials; combining VLX600 with conventional chemotherapy could be an innovative therapeutic strategy for neuroblastoma.

Neuroblastoma, the most common solid tumor in children, is characterized by amplification of the

Background South Asian adults have higher prevalence of obesity comorbidities than other ethnic groups. Whether this also is true for Sri Lankan children with obesity has rarely been investigated. Objective To investigate prevalence of glucose intolerance and other comorbidities in Sri Lankan children with obesity and compare them with Swedish children. To identify risk factors associated with glucose intolerance. Subjects A total of 357 Sri Lankan children (185 boys), aged 7 to 17 years with BMI-SDS ≥2.0 from a cross-sectional school screening in Negombo. A total of 167 subjects from this study population were matched for sex, BMI-SDS and age with 167 Swedish subjects from the ULSCO cohort for comparison. Methods After a 12 hour overnight fast, blood samples were collected and oral glucose tolerance test was performed. Body fat mass was assessed by bioelectrical impedance assay. Data regarding medical history and socioeconomic status were obtained from questionnaires. Results Based on levels of fasting glucose (FG) and 2 hours-glucose (2 hours-G), Sri Lankan subjects were divided into five groups: normal glucose tolerance (77.5%, n = 276), isolated impaired fasting glucose according to ADA criteria (9.0%, n = 32), isolated impaired glucose tolerance (8.4%, n = 30), combined impaired fasting glucose (IFG) + impaired glucose tolerance (IGT) (3.1%, n = 11) and type 2 diabetes mellitus (2.0%, n = 7). FG, 2 hours-insulin and educational status of the father independently increased the Odds ratio to have elevated 2 hours-G. Sri Lankan subjects had higher percentage of body fat, but less abdominal fat than Swedish subjects. Conclusion High prevalence in Sri Lankan children with obesity shows that screening for glucose intolerance is important even if asymptomatic.

Purpose: To compare patterns of sedentary (SED) time (more sedentary, SED+ vs less sedentary, SED-), moderate to vigorous physical activity (MVPA) time (more active, MVPA+ vs less active, MVPA-) and combinations of behaviors (SED-/MVPA+, SED-/MVPA-, SED+/MVPA+, SED+/MVPA-) regarding nonalcoholic fatty liver diseases (NAFLD) markers. Methods: This cross-sectional study included 134 subjects (13.4±2.2yrs, body mass index (BMI) 98.9±0.7 percentile, 48.5% females) who underwent 24h/7day accelerometry, anthropometric and biochemical markers (alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), AST/ALT and Fatty Liver Index (FLI)). A subgroup of 39 patients underwent magnetic resonance imaging-liver fat content (MRI-LFC).Results: Hepatic health was better in SED- [lower ALT, GGT and MRI-LFC (pvs SED+ and in MVPA+ [lower ALT (pvs MVPA- groups after adjustment for age, gender and Tanner stages. SED-/MVPA+ group had the best hepatic health. SED-/MVPA- group had lower ALT and GGT and higher AST/ALT (pConclusions: Lower SED time is associated with better hepatic health independently of MVPA. Reducing SED time might be a first step in the management of pediatric obesity NAFLD when increasing MVPA is not possible.

To compare patterns of sedentary (SED) time (more sedentary, SED + vs less sedentary, SED-), moderate to vigorous physical activity (MVPA) time (more active, MVPA + vs less active, MVPA-), and combinations of behaviors (SED-/MVPA + , SED-/MVPA-, SED + /MVPA + , SED + /MVPA-) regarding nonalcoholic fatty liver diseases (NAFLD) markers. This cross-sectional study included 134 subjects (13.4 ± 2.2 years, body mass index (BMI) 98.9 ± 0.7 percentile, 48.5% females) who underwent 24-h/7-day accelerometry, anthropometric, and biochemical markers (alanine aminotransferase (ALT) as first criterion, and aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), AST/ALT ratio as secondary criteria). A subgroup of 39 patients underwent magnetic resonance imaging-liver fat content (MRI-LFC). Hepatic health was better in SED- (lower ALT, GGT, and MRI-LFC (p 0.05), higher AST/ALT (p 0.01)) vs SED + and in MVPA + (lower ALT (p 0.05), higher AST/ALT (p 0.01)) vs MVPA- groups after adjustment for age, gender, and Tanner stages. SED-/MVPA + group had the best hepatic health. SED-/MVPA- group had lower ALT and GGT and higher AST/ALT (p 0.05) in comparison with SED + /MVPA + group independently of BMI. SED time was positively associated with biochemical (high ALT, low AST/ALT ratio) and imaging (high MRI-LFC) markers independently of MVPA. MVPA time was associated with biochemical markers (low ALT, high AST/ALT) but these associations were no longer significant after adjustment for SED time.Lower SED time is associated with better hepatic health independently of MVPA. Reducing SED time might be a first step in the management of pediatric obesity NAFLD when increasing MVPA is not possible.• MVPA and SED times are associated with cardiometabolic risks in youths with obesity. • The relationships between NAFLD markers and concomitant MVPA and SED times have not been studied in this population.• Low SED time is associated with healthier liver enzyme profiles and LFC independent of MVPA. • While low SED/high MVPA is the more desirable pattern, low SED/low MVPA pattern would have healthier liver enzyme profile compared with high MVPA/high SED, independent of BMI, suggesting that reducing SED time irrespective of MVPA is needed to optimize liver health.

Background During perimenopause, the rise in serum follicle-stimulating hormone (FSH) is associated with increased adiposity, insulin resistance (IR), and metabolic syndrome (MetS). However, data for the pubertal period, which is characterized by increasing FSH levels and changing body composition, are limited. Objectives To investigate the relationships between FSH and anthropometric changes, IR markers, and development of MetS in the peripubertal period. Methods Uppsala Longitudinal Study of Childhood Obesity (ULSCO) is an ongoing study that aims to understand the factors contributing to childhood obesity and the development of obesity-related diseases. We analysed the subset of participants who were prepubertal at the first visit (n = 95, 77 with obesity). Mean follow-up time was 3.0 +/- 1.4 years. Results Higher serum FSH levels at the first visit were associated with an increased likelihood of elevation in body mass index (BMI SDS) (p = 0.025, OR = 16.10) and having MetS (p = 0.044, OR = 4.67) at the follow-up. We observed nonlinear relationships between varying serum FSH levels and markers of adiposity and IR, especially in girls. At the first visit, when girls were prepubertal, FSH was negatively associated with BMI (beta = -0.491, p = 0.005) and positively associated with sex hormone-binding globulin (SHBG) (beta = 0.625, p = 0.002). With the progression of puberty, negative associations between BMI and SHBG disappeared while FSH became positively associated with HOMA-IR (beta = 0.678, p = 0.025) and fasting insulin (beta = 0.668, p = 0.027). Conclusions Higher serum FSH levels in prepubertal children were associated with an increased risk of MetS development during pubertal transition. Along with nonlinear associations between varying serum FSH levels and IR markers, our results might imply a relationship between FSH and IR of puberty.

Inborn errors of mitochondrial fatty acid oxidation (FAO), such as medium-chain acyl-CoA dehydrogenase deficiency (MCAD) and very long-chain acyl-CoA dehydrogenase deficiency (VLCAD) affects cellular function and whole-body metabolism. Carnitine uptake deficiency (CUD) disturbs the transportation of fatty acids into the mitochondria, but when treated is a mild disease without significant effects on FAO. For improved clinical care of VLCAD in particular, estimation of FAO severity could be important. We have investigated whether the oxygen consumption rate (OCR) of peripheral blood mononuclear cells (PBMCs) obtained from patients with MCAD, VLCAD, and CUD can be used to study cellular metabolism in patients with FAO defects and to determine the severity of FAO impairment. PBMCs were isolated from patients with VLCAD (n = 9), MCAD (n = 5–7), and CUD (n = 5). OCR was measured within 6-hours of venous puncture using the Seahorse XFe96. The PBMCs were exposed to glucose alone or with caprylic acid (C8:0) or palmitic acid (C16:0). OCR was significantly lower in cells from patients with β-oxidation deficiencies (MCAD and VLCAD) compared to CUD at basal conditions. When exposed to C16:0, OCR in VLCAD cells was unchanged, whereas OCR in MCAD cells increased but not to the levels observed in CUD. However, C8:0 did not increase OCR, as would be expected, in VLCAD cells. There was no clear relationship between clinical severity level and OCR. In patients with β-oxidation deficiencies, changes of mitochondrial respiration in PBMCs are detectable, which indicate that PBMCs have translational potential for studies of β-oxidation defects. However, further studies are warranted. Title in Web of Science: Altered mitochondrial metabolism in peripheral blood cells from patients with inborn errors of beta-oxidation

International audience; Background Relationships between movement-related behaviours and metabolic health remain underexplored in adolescents with obesity. Objectives To compare profiles of sedentary time (more sedentary, SED+ vs. less sedentary, SED-), moderate to vigorous physical activity (MVPA) time (more active, MVPA+ vs. less active, MVPA-) and combinations of behaviours (SED-/MVPA+, SED-/MVPA-, SED+/MVPA+, SED+/MVPA-) in regard to metabolic health. Methods One hundred and thirty-four subjects (mean age 13.4 +/- 2.2 yrs, mean body mass index [BMI] 98.9 +/- 0.7 percentile, 48.5% females) underwent 24 h/7 day accelerometry, anthropometric, body composition, blood pressure (BP), lipid profile and insulin resistance (IR) assessments. Results Metabolic health was better in SED- [lower fat mass (FM) percentage (p < 0.05), blood pressure (BP) (p < 0.05), homeostasis model assessment of insulin resistance (HOMA-IR) (p < 0.001) and metabolic syndrome risk score (MetScore) (p < 0.001), higher high-density lipoprotein-cholesterol (HDL-c) (p = 0.001)] vs. SED+ group and in MVPA+ [lower triglyceridemia (TG), (p < 0.05), HOMA-IR (p < 0.01) and MetScore (p < 0.001), higher HDL-c (p < 0.01)] vs. MVPA- group after adjustment with age, gender, maturation and BMI. SED-/MVPA+ group had the best metabolic health. While sedentary (p < 0.001) but also MVPA times (p < 0.001) were lower in SED-/MVPA- vs. SED+/MVPA+, SED-/MVPA- had lower FM percentage (p < 0.05), HOMA-IR (p < 0.01) and MetScore (p < 0.05) and higher HDL-c (p < 0.05), independently of BMI. Sedentary time was positively correlated with HOMA-IR and Metscore and negatively correlated with HDL-c after adjustment with MVPA (p < 0.05). MVPA was negatively correlated with HOMA-IR, BP and MetScore and positively correlated with HDL-c after adjustment with sedentary time (p < 0.05). Conclusion Lower sedentary time is associated with a better metabolic health independently of MVPA and might be a first step in the management of pediatric obesity when increasing MVPA is not possible.

Endoplasmic reticulum (ER) - plasma membrane (PM) contacts are sites of lipid exchange and Ca2+ transport, and both lipid transport proteins and Ca2+ channels specifically accumulate at these locations. In pancreatic β-cells, both lipid- and Ca2+ signaling are essential for insulin secretion. The recently characterized lipid transfer protein TMEM24 dynamically localize to ER-PM contact sites and provide phosphatidylinositol, a precursor of PI(4)P and PI(4,5)P2, to the plasma membrane. β-cells lacking TMEM24 exhibit markedly suppressed glucose-induced Ca2+ oscillations and insulin secretion but the underlying mechanism is not known. We now show that TMEM24 only weakly interact with the PM, and dissociates in response to both diacylglycerol and nanomolar elevations of cytosolic Ca2+. Release of TMEM24 into the bulk ER membrane also enables direct interactions with mitochondria, and we report that loss of TMEM24 results in excessive accumulation of Ca2+ in both the ER and mitochondria and in impaired mitochondria function.

Background In children with obesity, accentuated insulin secretion has been coupled with development of type 2 diabetes mellitus (T2DM). Bisphenol A (BPA) is a chemical with endocrine- and metabolism-disrupting properties which can be measured in a majority of the population. Exposure to BPA has been associated with the development of metabolic diseases including T2DM. Objective The aim of this study was to investigate if exposure early in life to an environmentally relevant low dose of BPA causes insulin hypersecretion in rat offspring. Methods Pregnant Fischer 344 rats were exposed to 0.5 (BPA0.5) or 50 (BPA50) µg BPA/kg BW/day via drinking water from gestational day 3.5 until postnatal day 22. Pancreata from dams and 5- and 52-week-old offspring were procured and islets were isolated by collagenase digestion. Glucose-stimulated insulin secretion and insulin content in the islets were determined by ELISA. Results Basal (5.5 mM glucose) islet insulin secretion was not affected by BPA exposure. However, stimulated (11 mM glucose) insulin secretion was enhanced by about 50% in islets isolated from BPA0.5-exposed 5- and 52-week-old female and male offspring and by 80% in islets from dams, compared with control. In contrast, the higher dose, BPA50, reduced stimulated insulin secretion by 40% in both 5- and 52-week-old female and male offspring and dams, compared with control. Conclusion A BPA intake 8 times lower than the European Food Safety Authority's (EFSA's) current tolerable daily intake (TDI) of 4 µg/kg BW/day of BPA delivered via drinking water during gestation and early development causes islet insulin hypersecretion in rat offspring up to one year after exposure. The effects of BPA exposure on the endocrine pancreas may promote the development of metabolic disease including T2DM.

Background Fatty acids (FAs), and especially monounsaturated FAs (MUFAs) stimulate GLP-1 release. However, lipotoxicity is indicated in GLP-1 secreting cells following long-term exposure to elevated levels of saturated FAs (SFAs) in vivo and in vitro, where in vitro studies indicate that cosupplementation with MUFAs confers lipoprotection. SFAs and MUFAs differentially affect the fate of cells in ways that depend on the cell type, concentration and ratio of the FAs. The present study was designed to further elucidate the mechanisms underlying the effects of SFAs/MUFAs on GLP-1-producing cells in terms of lipotoxicity/lipoprotection and GLP-1 secretion. Methods Cultured GLP-1 secreting cells were exposed to hyperlipidemia simulated by SFA-albumin complexes where the molar ratio was 2:1. The cellular response to simulated hyperlipidemia was assessed in the presence/absence of MUFA cosupplementation by determining intracellular ceramide, ROS, neutral lipid accumulation, and cellular respiration. The role for cellular respiration in GLP-1 secretion in response to SFAs/MUFAs was assessed. Results Generation of intracellular ceramide mediate a detrimental increased in ROS production following long term exposure to SFAs in GLP-1-secreting cells. Cosupplementation with MUFAs increases cellular respiration, triglyceride synthesis, and the expression of ceramide kinase, while reducing ceramide synthesis and attenuating ROS production, caspase-3 activity and DNA fragmentation. Further, acute secretory effects of unsaturated FAs are independent of FAO, but mediated by a FFAR1 induced increase in cellular respiration. Conclusion This study demonstrates novel data supporting effects of MUFAs on the ceramide biosynthetic pathway, triglyceride storage respiration and secretion in GLP-1 secreting cells. These findings may be of value for nutritional interventions, as well as for identification of novel targets, to help preserve L-cell mass and potentiate GLP-1 secretion in diabesity.

Inhibition of 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase is associated with an increased risk of new-onset type 2 diabetes. We studied the association of genetic or pharmacological HMG-CoA reductase inhibition with plasma and adipose tissue (AT) metabolome and AT metabolic pathways. We also investigated the effects of statin-mediated pharmacological inhibition of HMG-CoA reductase on systemic insulin sensitivity by measuring the HOMA-IR index in subjects with or without statin therapy. The direct effects of simvastatin (20–250 nM) or its active metabolite simvastatin hydroxy acid (SA) (8–30 nM) were investigated on human adipocyte glucose uptake, lipolysis, and differentiation and pancreatic insulin secretion. We observed that the LDL-lowering HMGCR rs12916-T allele was negatively associated with plasma phosphatidylcholines and sphingomyelins, and HMGCR expression in AT was correlated with various metabolic and mitochondrial pathways. Clinical data showed that statin treatment was associated with HOMA-IR index after adjustment for age, sex, BMI, HbA1c, LDL-c levels, and diabetes status in the subjects. Supra-therapeutic concentrations of simvastatin reduced glucose uptake in adipocytes and normalized fatty acid-induced insulin hypersecretion from β-cells. Our data suggest that inhibition of HMG-CoA reductase is associated with insulin resistance. However, statins have a very mild direct effect on AT and pancreas, hence, other tissues as the liver or muscle appear to be of greater importance. Title in Web of Science: Impaired HMG-CoA Reductase Activity Caused by Genetic Variants or Statin Exposure: Impact on Human Adipose Tissue, beta-Cells and Metabolome

Childhood obesity-related metabolic derangements are increasing among South Asian populations. Most of these changes persist to adulthood. This study aims to describe the distribution of metabolic abnormalities among 7- to 17-year-old overweight and obese children in the Gampaha District of Sri Lanka. Overweight children (age- and gender-adapted BMI>+1SD, WHO standards) were selected from a community survey carried out in the Negombo Education Zone of Gampaha District. After a 12-hour overnight fast, blood was drawn, and blood glucose (FBG), lipid profile, insulin, and liver transaminases were measured. Two hours after a glucose load, blood was drawn for random blood glucose (RBG) and insulin. Metabolic syndrome (MetS) was diagnosed using modified IDF criteria for children. Anthropometry, fat mass (FM), and blood pressure were measured. Hepatic fat pattern was assessed ultrasonically. The data of 403 children (210 boys) were analysed. Of the study population, 16.4% were overweight (BMI for age +1 to +2SD), 72% were obese (BMI for age >+2 to +3SD), and 11.6% were severely obese (BMI for age >+3SD). Insulin resistance was seen in 46.8%, and prevalence increased with age. Mean postprandial insulin ranged from 368 to 625 pmol/L and was elevated in 35%. Dysglycaemia was seen among 20.8%. MetS was present in 19.8%, and 84% had at least one metabolic abnormality. Different degrees of hepatic steatosis were observed in 32.5%, and elevated ALT/AST ratio was seen in 58% of the population. Overweight and obesity during childhood were associated with multiple metabolic abnormalities including MetS, and they occur from a young age. It is important to screen children for overweight/obesity early in life and intervene to prevent them from developing metabolic complications.

BACKGROUND: Pharmacological treatment options for adolescents with obesity are very limited. Glucagon-like-peptide-1 (GLP-1) receptor agonist could be a treatment option for adolescent obesity. OBJECTIVE: To investigate the effect of exenatide extended release on body mass index (BMI)-SDS as primary outcome, and glucose metabolism, cardiometabolic risk factors, liver steatosis, and other BMI metrics as secondary outcomes, and its safety and tolerability in adolescents with obesity. METHODS: Six-month, randomized, double-blinded, parallel, placebo-controlled clinical trial in patients (n = 44, 10-18 years, females n = 22) with BMI-SDS > 2.0 or age-adapted-BMI > 30 kg/m2 according to WHO were included. Patients received lifestyle intervention and were randomized to exenatide extended release 2 mg (n = 22) or placebo (n = 22) subcutaneous injections given once weekly. Oral glucose tolerance tests (OGTT) were conducted at the beginning and end of the intervention. RESULTS: Exenatide reduced (P De två första författarna delar förstaförfattarskapet

Elevated levels of palmitate accentuate glucose-stimulated insulin secretion (GSIS) after short-term and cause beta-cell dysfunction after prolonged exposure. We investigated whether metformin, the first-line oral drug for treatment of T2DM, has beneficial effects on FFA-treated human islets and the potential mechanisms behind the effects. Insulin secretion, oxygen consumption rate (OCR), AMPK activation, endoplasmic reticulum (ER) stress and apoptosis were examined in isolated human islets after exposure to elevated levels of palmitate in the absence or presence of metformin. Palmitate exposure doubled GSIS after 2 days but halved after 7 days compared with control. Inclusion of metformin during palmitate exposure normalized insulin secretion both after 2 and 7 days. After 2-day exposure to palmitate, OCR and the marker of the adaptive arm of ER stress response (sorcin) were significantly raised, whereas AMPK phosphorylation, markers of pro-apoptotic arm of ER stress response (p-EIF2α and CHOP) and apoptosis (cleaved caspase 3) were not affected. Presence of metformin during 2-day palmitate exposure normalized OCR and sorcin levels. After 7-day exposure to palmitate, OCR and sorcin were not significantly different from control level, p-AMPK was reduced and p-EIF2α, CHOP and cleaved caspase 3 were strongly upregulated. Presence of metformin during 7-day culture with palmitate normalized the level of p-AMPK, p-EIF2α, CHOP and cleaved caspase 3 but significantly increased the level of sorcin. Our study demonstrates that metformin prevents early insulin hypersecretion and later decrease in insulin secretion from palmitate-treated human islets by utilizing different mechanisms.

Association Between Non-Alcoholic Fatty Liver Disease (NAFLD) and Iron Metabolism in Obese Children and Adolescents : Results of the Beta-JUDO Study

Despite socioeconomic improvement, undernutrition rates stagnate in Sri Lanka, while a slow rise in obesity and noncommunicable diseases (NCD) is seen. Inability to improve undernutrition and detection of NCD could be due to overdiagnosing stunting/wasting and underdiagnosing overweight/obesity. Obesity, being a risk factor for NCDs, needs correct tools for early diagnosis. Although body mass index (BMI) is a commonly used surrogate index, the validity of universal cutoffs is questioned. Evidence shows that body composition varies with ethnic origin and cutoff value reflecting fat mass (FM) varies in different ethnic groups. This study was conducted in 12 788, 5- to 15-year-old children from 8 schools in Negombo, Sri Lanka, to identify the validity of current anthropometric cutoffs. Obesity prevalence identified by body fat content was high. International BMI cutoffs had high specificity but varied sensitivity. Locally developed BMI cutoffs had high sensitivity and specificity. Validity of internationally developed anthropometric cutoffs in South Asian children is unsatisfactory; hence, locally/regionally developed anthropometric tools should be used for screening of obesity.

The transcription factor ZBED6 acts as a repressor of Igf2 and affects directly or indirectly the transcriptional regulation of thousands of genes. Here, we use gene editing in mouse C2C12 myoblasts and show that ZBED6 regulates Igf2 exclusively through its binding site 5 '-GGCTCG-3 ' in intron 1 of Igf2. Deletion of this motif (Igf2(Delta GGCT)) or complete ablation of Zbed6 leads to similar to 20-fold upregulation of the IGF2 protein. Quantitative proteomics revealed an activation of Ras signaling pathway in both Z bed6(-/-) and Igf2(Delta GGCT) myoblasts, and a significant enrichment of mitochondrial membrane proteins among proteins showing altered expression in Z bed6(-/-)myoblasts. BothZbed6(-/-)andIgf2(Delta GGCT)myoblasts showed a faster growth rate and developed myotube hypertrophy. These cells exhibited an increased O-2 consumption rate, due to IGF2 upregulation. Transcriptome analysis revealed similar to 30% overlap between differentially expressed genes in Z bed6(-/-) and Igf2(Delta GGCT) myotubes, with an enrichment of upregulated genes involved in muscle development. In contrast, ZBED6-overexpression in myoblasts led to cell apoptosis, cell cycle arrest, reduced mitochondrial activities, and ceased myoblast differentiation. The similarities in growth and differentiation phenotypes observed in Z bed6(-/-)and Igf2(Delta GGCT) myoblasts demonstrates that ZBED6 affects mitochondrial activity and myogenesis largely through its regulation of IGF2 expression. This study adds new insights how the ZBED6-Igf2 axis affects muscle metabolism.

SUMMARYThe transcription factor ZBED6 acts as a repressor ofIgf2and affects directly or indirectly the transcriptional regulation of thousands of genes. Here, we use gene editing in mouse C2C12 myoblasts and show that ZBED6 regulatesIgf2exclusively through its binding site 5′-GGCTCG-3′ in intron 1 ofIgf2. Deletion of this motif (Igf2ΔGGCT) or complete ablation ofZbed6leads to ~20-fold up-regulation of IGF2 protein. Quantitative proteomics revealed an activation of Ras signaling pathway in bothZbed6-/-andIgf2ΔGGCTmyoblasts, and a significant enrichment of mitochondrial membrane proteins among proteins showing altered expression inZbed6-/-myoblasts. BothZbed6-/-andIgf2ΔGGCTmyoblasts showed a faster growth rate and developed myotube hypertrophy. These cells exhibited an increased O2consumption rate, due to IGF2 up-regulation. Transcriptome analysis revealed ~30% overlap between differentially expressed genes inZbed6-/-andIgf2ΔGGCTmyotubes, with an enrichment of up-regulated genes involved in muscle development. In contrast, ZBED6-overexpression in myoblasts led to cell apoptosis, cell cycle arrest, reduced mitochondrial activities and ceased myoblast differentiation. The similarities in growth and differentiation phenotypes observed inZbed6-/-andIgf2ΔGGCTmyoblasts demonstrates that ZBED6 affects mitochondrial activity and myogenesis largely through its regulation of IGF2 expression. This study suggests that the interaction between ZBED6-Igf2may be a therapeutic target for human diseases where anabolism is impaired.

Objective: To delineate mechanisms for fasting hyperglucagonemia in childhood obesity bystudying the associations between fasting plasma glucagon concentrations and plasmalipid parameters and fat compartments. Methods: Cross-sectional study of children and adolescents with obesity (n=147) and leancontrols (n=43). Differences in free fatty acids (FFA), triglycerides, insulin and fatcompartments (quantified by magnetic resonance imaging) across quartiles of fastingplasma glucagon concentration were analysed. Differences in OGTT glucagonresponse was tested in high vs low FFAs, triglycerides and insulin. Human islets ofLangerhans were cultured at 5.5 mmol/l glucose and in the absence or presence of aFFA mixture with total FFA concentration of 0.5 mmol/l and glucagon secretionquantified. Results: In children with obesity, the quartile with the highest fasting glucagon had higherinsulin (201±174 vs 83±39 pmol/l, p

Cardiovascular risk is increased in obese subjects. Nevertheless, some overweight and obese remain cardiometabolically healthy (CMH), and normal-weight persons develop cardiovascular disease (CVD). Herein, we investigate the potential of branched-chain amino acids (BCAAs) to identify an increased CVD risk in a cross-sectional study of 666 adults and juveniles (age 25.3±12.8years), classified as lean, overweight or obese. Cardiometabolic groups were defined by cutoffs of systolic blood pressure130mmHg, diastolic blood pressure85mmHg, glucose125mg/dl, triglycerides150mg/dl, HDL-cholesterol40mg/dl (males), HDL-cholesterol50mg/dl (females) and HOMA-IR5. CMH had ≤1 cutoff, and cardiometabolically abnormal (CMA) had ≥2 cutoffs. Amino acids were measured by high-pressure lipid chromatography after precipitation of serum with perchloric acid and derivatization with o-phthalaldehyde. Valine correlated with 5, leucine correlated with 3 and isoleucine correlated with 5 of the cardiac risk classification factors. Valine and leucine were significantly higher in the obese (P.001, P=.015, respectively), overweight (P.001, P=.015, respectively) and lean (P=.024, P=.012, respectively) CMA compared to CMH subjects. Isoleucine showed except of the lean group the same results. Taken together, BCAAs, especially valine and leucine, are proposed as a cardiometabolic risk marker independent of body mass index (BMI) category.

The naturally occurring quassinoid compound brusatol improves the survival of insulin-producing cells when exposed to the proinflammatory cytokines IL-1β and IFN-γ in vitro. The aim of the present study was to investigate whether brusatol also promotes beneficial effects in mice fed a high-fat diet (HFD), and if so, to study the mechanisms by which brusatol acts. In vivo, we observed that the impaired glucose tolerance of HFD-fed male C57BL/6 mice was counteracted by a 2 wk treatment with brusatol. Brusatol treatment improved both β-cell function and peripheral insulin sensitivity of HFD-fed mice. In vitro, brusatol inhibited β-cell total protein and proinsulin biosynthesis, with an ED50 of ∼40 nM. In line with this, brusatol blocked cytokine-induced iNOS protein expression via inhibition of iNOS mRNA translation. Brusatol may have affected protein synthesis, at least in part, via inhibition of eukaryotic initiation factor 5A (eIF5A) hypusination, as eIF5A spermidine association and hypusination in RIN-5AH cells was reduced in a dose- and time-dependent manner. The eIF5A hypusination inhibitor GC7 promoted a similar effect. Both brusatol and GC7 protected rat RIN-5AH cells against cytokine-induced cell death. Brusatol reduced eIF5A hypusination and cytokine-induced cell death in EndoC-βH1 cells as well. Finally, hypusinated eIF5A was reduced in vivo by brusatol in islet endocrine and endothelial islet cells of mice fed an HFD. The results of the present study suggest that brusatol improves glucose intolerance in mice fed an HFD, possibly by inhibiting protein biosynthesis and eIF5A hypusination.-Turpaev, K., Krizhanovskii, C., Wang, X., Sargsyan, E., Bergsten, P., Welsh, N. The protein synthesis inhibitor brusatol normalizes high-fat diet-induced glucose intolerance in male C57BL/6 mice: role of translation factor eIF5A hypusination.

Summary Background Despite therapeutic potential against obesity and diabetes, the associations of brown adipose tissue (BAT) with glucose metabolism in young humans are relatively unexplored. Objectives To investigate possible associations between magnetic resonance imaging (MRI) estimates of BAT and glucose metabolism, whilst considering sex, age, and adiposity, in adolescents with normal and overweight/obese phenotypes. Methods In 143 subjects (10‐20 years), MRI estimates of BAT were assessed as cervical‐supraclavicular adipose tissue (sBAT) fat fraction (FF) and T2* from water‐fat MRI. FF and T2* of neighbouring subcutaneous adipose tissue (SAT) were also assessed. Adiposity was estimated with a standardized body mass index, the waist‐to‐height ratio, and abdominal visceral and subcutaneous adipose tissue volumes. Glucose metabolism was represented by the 2h plasma glucose concentration, the Matsuda index, the homeostatic model assessment of insulin resistance, and the oral disposition index; obtained from oral glucose tolerance tests. Results sBAT FF and T2* correlated positively with adiposity before and after adjustment for sex and age. sBAT FF, but not T2*, correlated with 2h glucose and Matsuda index, also after adjustment for sex, age, and adiposity. The association with 2h glucose persisted after additional adjustment for SAT FF. Conclusions The association between sBAT FF and 2h glucose, observed independently of sex, age, adiposity, and SAT FF, indicates a role for BAT in glucose metabolism, which potentially could influence the risk of developing diabetes. The lacking association with sBAT T2* might be due to FF being a superior biomarker for BAT and/or to methodological limitations in the T2* quantification.

We have previously reported that insulin and glucagon levels at fasting and during OGTT are increased in obese adolescents as glucose intolerance develops. In adults incretin hormone GIP has been coupled with enhanced glucagon secretion. We hypothesized that the observed elevated glucagon levels in obese adolescents were associated with increased levels of GIP. Total GIP in plasma samples from obese (NGT=7, IGT=9, T2DM=4) and lean (n=8) adolescents was measured at fasting and during OGTT with a newly developed ELISA (Mercodia AB, Uppsala, Sweden). Newly secreted GIP and glucagon were defined as GIP and glucagon area under curve AUC during the first 30 min, AUC30. Ethical approval was obtained from the Uppsala Ethical Review Board. Fasting GIP levels ± SEM were 4.7 ± 2.8, 3.6 ± 2.0, 2.9 ± 1.7 and 2.2 ± 0.9 pM in lean, obese NGT, obese IGT and obese T2DM adolescents, respectively. During OGTT GIP concentrations peaked at 30 min for all groups (Figure). Highest concentrations were observed throughput the OGTT in lean, followed by obese NGT, obese IGT and obese T2DM adolescents. GIP AUC30 ± SEM was 1181 ± 197, 920 ± 22, 707 ± 146 and 699 ± 211 pmol/L *min in lean, obese NGT, obese IGT and obese T2DM, respectively. For the same groups glucagon AUC30 ± SEM was -73 ± 21, -39 ± 43, -3 ± 30 and 91 ± 80 pmol/L *min. Hyperglucagonemia in adolescents developing T2DM does not seem to be driven by enhanced GIP secretion. Disclosure H. Kristinsson: None. H. Manell: None. M. Vilhelmsson: Employee; Self; Mercodia AB. J. Presto: Employee; Self; Mercodia AB. C. Gäredal: None. H. Ritzén: None. A.H. Forslund: None. P. Bergsten: None.