Intra-Individual Variations in How Insulin Sensitivity Responds to Long-Term Exercise: Predictions by Machine Learning Based on Large-Scale Serum Proteomics.

Physical activity is effective for preventing and treating type 2 diabetes, but some individuals do not achieve metabolic benefits from exercise ("non-responders"). We investigated non-responders in terms of insulin sensitivity changes following a 12-week supervised strength and endurance exercise program. We used a hyperinsulinaemic euglycaemic clamp to measure insulin sensitivity among 26 men aged 40-65, categorizing them into non-responders or responders based on their insulin sensitivity change scores. The exercise regimen included VO2max, muscle strength, whole-body MRI scans, muscle and fat biopsies, and serum samples. mRNA sequencing was performed on biopsies and Olink proteomics on serum samples. Non-responders showed more visceral and intramuscular fat and signs of dyslipidaemia and low-grade inflammation at baseline and did not improve in insulin sensitivity following exercise, although they showed gains in VO2max and muscle strength. Impaired IL6-JAK-STAT3 signalling in non-responders was suggested by serum proteomics analysis, and a baseline serum proteomic machine learning (ML) algorithm predicted insulin sensitivity responses with high accuracy, validated across two independent exercise cohorts. The ML model identified 30 serum proteins that could forecast exercise-induced insulin sensitivity changes.

Adipose Tissue Insulin Resistance in South Asian and Nordic Women after Gestational Diabetes Mellitus.

South Asians (SAs) have a higher risk of developing type 2 diabetes (T2D) than white Europeans, especially following gestational diabetes mellitus (GDM). Despite similar blood glucose levels post-GDM, SAs exhibit more insulin resistance (IR) than Nordics, though the underlying mechanisms are unclear. This study aimed to assess markers of adipose tissue (AT) IR and liver fat in SA and Nordic women post-GDM. A total of 179 SA and 108 Nordic women in Norway underwent oral glucose tolerance tests 1-3 years post-GDM. We measured metabolic markers and calculated the AT IR index and non-alcoholic fatty liver disease liver fat (NAFLD-LFS) scores. Results showed that normoglycaemic SAs had less non-esterified fatty acid (NEFA) suppression during the test, resembling prediabetes/T2D responses, and higher levels of plasma fetuin-A, CRP, and IL-6 but lower adiponectin, indicating AT inflammation. Furthermore, normoglycaemic SAs had higher NAFLD-LFS scores, lower insulin clearance, and higher peripheral insulin than Nordics, indicating increased AT IR, inflammation, and liver fat in SAs. Higher liver fat markers significantly contributed to the ethnic disparities in glucose metabolism, suggesting a key area for intervention to reduce T2D risk post-GDM in SAs.

Cohort profile update: the Norwegian STORK Groruddalen (STORK G) pregnancy and birth cohort-the role of ethnicity and causal pathways for obesity, type 2 diabetes, cardiovascular disease and other health issues.

PURPOSE: The STORK Groruddalen cohort was set up in 2008 to explore ethnic differences in: (1) maternal health, primarily gestational diabetes (GDM) and related health issues during pregnancy and post partum, and effects of exposures on risk for type 2 diabetes, cardiovascular disease and other health issues, and (2) offspring's growth and body composition, overweight/obesity and effects of early life exposures. PARTICIPANTS: 823 women (74% of invited) were followed from gestational week (GW) 15. Data were collected from 618 fathers. In total, 59% of women and 53% of fathers had origin from non-Western countries. Maternal mean age was 29.9 years (SD 4.9), and body mass index (BMI) 25.3 kg/m2 (4.9). Data were obtained from 772 women (94%) at GW 28, and 662 women (80%) 14 weeks post partum. Eleven years post partum, 385 women (53% of eligible/47% of original cohort) attended, age was 42.0 years (4.8) and BMI 27.1 kg/m2 (5.1). We have data for 783 children at birth, and for 586 at last time point, mean age 8.6 (0.5) years, weight 30.7 (6.8) kg and length 133.9 (6.3) cm. FINDINGS TO DATE: We collected questionnaire data from parents, clinical measurements and blood samples from mothers, and data on children's growth (mid-pregnancy to 8 years). Our biobank includes maternal blood and urine samples, biopsy material from placentas and umbilical venous cord blood. We found several clinically important differences in maternal health, with higher risk in ethnic minority groups for GDM, insulin resistance, vitamin D and iron deficiency, depressive symptoms and physical inactivity. Contrasting patterns of fetal growth and risk of overweight/thinness at preschool age were observed across ethnic groups. Maternal GDM, obesity and high gestational weight gain were associated with children's BMI trajectories. FUTURE PLANS: We will examine the impact of maternal and fetal health and development during pregnancy on long-term outcomes for mothers and offspring. TRIAL REGISTRATION NUMBER: Project title STORK G-2: Women and Risk of Type 2 Diabetes NCT03870724 (ClinicalTrials.gov).

Impaired Adipocyte SLC7A10 Promotes Lipid Storage in Association With Insulin Resistance and Altered BCAA Metabolism.

CONTEXT: The neutral amino acid transporter SLC7A10/ASC-1 is an adipocyte-expressed gene with reduced expression in insulin resistance and obesity. Inhibition of SLC7A10 in adipocytes was shown to increase lipid accumulation despite decreasing insulin-stimulated uptake of glucose, a key substrate for de novo lipogenesis. These data imply that alternative lipogenic substrates to glucose fuel continued lipid accumulation during insulin resistance in obesity. OBJECTIVE: We examined whether increased lipid accumulation during insulin resistance in adipocytes may involve alter flux of lipogenic amino acids dependent on SLC7A10 expression and activity, and whether this is reflected by extracellular and circulating concentrations of marker metabolites. METHODS: In adipocyte cultures with impaired SLC7A10, we performed RNA sequencing and relevant functional assays. By targeted metabolite analyses (GC-MS/MS), flux of all amino acids and selected metabolites were measured in human and mouse adipose cultures. Additionally, SLC7A10 mRNA levels in human subcutaneous adipose tissue (SAT) were correlated to candidate metabolites and adiposity phenotypes in 2 independent cohorts. RESULTS: SLC7A10 impairment altered expression of genes related to metabolic processes, including branched-chain amino acid (BCAA) catabolism, lipogenesis, and glyceroneogenesis. In 3T3-L1 adipocytes, SLC7A10 inhibition increased fatty acid uptake and cellular content of glycerol and cholesterol. SLC7A10 impairment in SAT cultures altered uptake of aspartate and glutamate, and increased net uptake of BCAAs, while increasing the net release of the valine catabolite 3- hydroxyisobutyrate (3-HIB). In human cohorts, SLC7A10 mRNA correlated inversely with total fat mass, circulating triacylglycerols, BCAAs, and 3-HIB. CONCLUSION: Reduced SLC7A10 activity strongly affects flux of BCAAs in adipocytes, which may fuel continued lipogenesis during insulin resistance, and be reflected in increased circulating levels of the valine-derived catabolite 3-HIB.

Potential Mechanisms for How Long-Term Physical Activity May Reduce Insulin Resistance.

Insulin became available for the treatment of patients with diabetes 100 years ago, and soon thereafter it became evident that the biological response to its actions differed markedly between individuals. This prompted extensive research into insulin action and resistance (IR), resulting in the universally agreed fact that IR is a core finding in patients with type 2 diabetes mellitus (T2DM). T2DM is the most prevalent form of diabetes, reaching epidemic proportions worldwide. Physical activity (PA) has the potential of improving IR and is, therefore, a cornerstone in the prevention and treatment of T2DM. Whereas most research has focused on the acute effects of PA, less is known about the effects of long-term PA on IR. Here, we describe a model of potential mechanisms behind reduced IR after long-term PA to guide further mechanistic investigations and to tailor PA interventions in the therapy of T2DM. The development of such interventions requires knowledge of normal glucose metabolism, and we briefly summarize an integrated physiological perspective on IR. We then describe the effects of long-term PA on signaling molecules involved in cellular responses to insulin, tissue-specific functions, and whole-body IR.

Gastrointestinal Hormones and ß-Cell Function After Gastric Bypass and Sleeve Gastrectomy: A Randomized Controlled Trial (Oseberg).

CONTEXT: Whether Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) differentially affect postprandial gastrointestinal hormones and ß-cell function in type 2 diabetes remains unclear. OBJECTIVE: We aimed to compare gastrointestinal hormones and ß-cell function, assessed by an oral glucose tolerance test (OGTT) 5 weeks and 1 year after surgery, hypothesizing higher glucagon-like peptide-1 (GLP-1) levels and greater ß-cell response to glucose after RYGB than after SG. METHODS: This study was a randomized, triple-blind, single-center trial at a tertiary care center in Norway. The primary outcomes were diabetes remission and IVGTT-derived ß-cell function. Participants with obesity and type 2 diabetes were allocated (1:1) to RYGB or SG. We measured gastrointestinal hormone profiles and insulin secretion as ß-cell glucose sensitivity (ß-GS) derived from 180-minute OGTTs. RESULTS: Participants were 106 patients (67% women), mean (SD) age 48 (10) years. Diabetes remission rates at 1 year were higher after RYGB than after SG (77% vs 48%; P = 0.002). Incremental area under the curve (iAUC0-180) GLP-1 and ß-GS increased more after RYGB than after SG, with 1-year between-group difference 1173 pmol/L*min (95% CI, 569-1776; P = 0.0010) and 0.45 pmol/kg/min/mmol (95% CI, 0.15-0.75; P = 0.0032), respectively. After surgery, fasting and postprandial ghrelin levels were higher and decremental AUC0-180 ghrelin, iAUC0-180 glucose-dependent insulinotropic polypeptide, and iAUC0-60 glucagon were greater after RYGB than after SG. Diabetes remission at 1 year was associated with higher ß-GS and higher GLP-1 secretion. CONCLUSION: RYGB was associated with greater improvement in ß-cell function and higher postprandial GLP-1 levels than SG.

Patient selection for islet or solid organ pancreas transplantation: experiences from a multidisciplinary outpatient-clinic approach.

OBJECTIVE: ß-cell replacement therapy (ßCRT), including pancreas transplantation alone (PTA) and islet transplantation (ITX), is a treatment option for selected type 1 diabetes patients. All potential candidates for ßCRT in Norway are referred to one national transplant centre for evaluation before any pre-transplant workup is started. This evaluation was performed by a transplant nephrologist alone prior to 2015 and by a multidisciplinary team (MDT) from 2015. We have reviewed the allocation of patients to treatment modality and the 1-year clinical outcome for the patients after transplantation. RESEARCH DESIGN AND METHODS: Medical charts of all patients evaluated for ßCRT between 2010 and 2020 in Norway were retrospectively analysed and the outcome of patients receiving ßCRT were studied. RESULTS: One hundred and forty-four patients were assessed for ßCRT eligibility between 2010 and 2020. After MDT evaluation was introduced for ßCRT eligibility in 2015, the percentage of referred patients accepted for the transplant waiting list fell from 84% to 40% (P < 0.005). One year after transplantation, 73% of the PTA and none of the ITX patients were independent of exogenous insulin, 8% of the PTA and 90% of the ITX patients had partial graft function while 19% of the PTA and 10% of the ITX patients suffered from graft loss. CONCLUSION: The acceptance rate for ßCRT was significantly reduced during a 10-year observation period and 81% of the PTA and 90% of the ITX patients had partial or normal graft function 1 year post-transplant.

Gastric bypass versus sleeve gastrectomy in patients with type 2 diabetes (Oseberg): a single-centre, triple-blind, randomised controlled trial.

BACKGROUND: For patients with obesity and type 2 diabetes, weight loss improves insulin sensitivity and ß-cell function, and can induce remission of diabetes. The comparative efficacy of various bariatric procedures for the remission of type 2 diabetes has not been fully elucidated. We aimed to compare the effects of the two most common bariatric procedures, gastric bypass and sleeve gastrectomy, on remission of diabetes and ß-cell function. METHODS: We conducted a single-centre, triple-blind, randomised trial at Vestfold Hospital Trust (Tønsberg, Norway), in which patients (aged ≥18 years) with type 2 diabetes and obesity were randomly assigned (1:1) to receive gastric bypass or sleeve gastrectomy (the Oseberg study). Randomisation was performed with a computerised random number generator and a block size of 10. Treatment allocation was masked from participants, study personnel, and outcome assessors and was concealed with sealed opaque envelopes. Surgeons used identical skin incisions during both surgeries and were not involved in patient follow-up. The primary clinical outcome was the proportion of participants with complete remission of type 2 diabetes (HbA1c of ≤6·0% [42 mmol/mol] without the use of glucose-lowering medication) at 1 year after surgery. The primary physiological outcome was disposition index (a measure of ß-cell function) at 1 year after surgery, as assessed by an intravenous glucose tolerance test. Primary outcomes were analysed in the intention-to-treat and per-protocol populations. This trial is ongoing and closed to recruitment, and is registered with ClinicalTrials.gov, NCT01778738. FINDINGS: Between Oct 15, 2012, and Sept 1, 2017, 1305 patients who were preparing for bariatric surgery were screened, of whom 319 consecutive patients with type 2 diabetes were assessed for eligibility. 109 patients were enrolled and randomly assigned to gastric bypass (n=54) or sleeve gastrectomy (n=55). 107 (98%) of 109 patients completed 1-year follow-up, with one patient in each group withdrawing after surgery (per-protocol population). In the intention-to-treat population, diabetes remission rates were higher in the gastric bypass group than in the sleeve gastrectomy group (risk difference 27% [95% CI 10 to 44]; relative risk [RR] 1·57 [1·14 to 2·16], p=0·0054); results were similar in the per-protocol population (risk difference 27% [95% CI 10 to 45]; RR 1·57 [1·14 to 2·15], p=0·0036). In the intention-to-treat population, disposition index increased in both groups (between-group difference 55 [-111 to 220], p=0·52); results were similar in the per-protocol population (between-group difference 21 [-214 to 256], p=0.86). In the gastric bypass group, ten of 54 participants had early complications and 17 of 53 had late side-effects. In the sleeve gastrectomy group, eight of 55 participants had early complications and 22 of 54 had late side-effects. No deaths occurred in either group. INTERPRETATION: Gastric bypass was found to be superior to sleeve gastrectomy for remission of type 2 diabetes at 1 year after surgery, and the two procedures had a similar beneficial effect on ß-cell function. The use of gastric bypass as the preferred bariatric procedure for patients with obesity and type 2 diabetes could improve diabetes care and reduce related societal costs. FUNDING: Morbid Obesity Centre, Vestfold Hospital Trust.

Single-centre, triple-blinded, randomised, 1-year, parallel-group, superiority study to compare the effects of Roux-en-Y gastric bypass and sleeve gastrectomy on remission of type 2 diabetes and ß-cell function in subjects with morbid obesity: a protocol for the Obesity surgery in Tønsberg (Oseberg) study.

INTRODUCTION: Bariatric surgery is increasingly recognised as an effective treatment option for subjects with type 2 diabetes and obesity; however, there is no conclusive evidence on the superiority of Roux-en-Y gastric bypass or sleeve gastrectomy. The Oseberg study was designed to compare the effects of gastric bypass and sleeve gastrectomy on remission of type 2 diabetes and ß-cell function. METHODS AND ANALYSIS: Single-centre, randomised, triple-blinded, two-armed superiority trial carried out at the Morbid Obesity Centre at Vestfold Hospital Trust in Norway. Eligible patients with type 2 diabetes and obesity were randomly allocated in a 1:1 ratio to either gastric bypass or sleeve gastrectomy. The primary outcome measures are (1) the proportion of participants with complete remission of type 2 diabetes (HbA1c≤6.0% in the absence of blood glucose-lowering pharmacologic therapy) and (2) ß-cell function expressed by the disposition index (calculated using the frequently sampled intravenous glucose tolerance test with minimal model analysis) 1 year after surgery. ETHICS AND DISSEMINATION: The protocol of the current study was reviewed and approved by the regional ethics committee on 12 September 2012 (ref: 2012/1427/REK sør-øst B). The results will be disseminated to academic and health professional audiences and the public via publications in international peer-reviewed journals and conferences. Participants will receive a summary of the main findings. TRIAL REGISTRATION NUMBER: NCT01778738;Pre-results.

Non-invasive prediction of blood glucose trends during hypoglycemia.

Over the last four decades, there has been a pursuit for a non-invasive solution for glucose measurement, but there is not yet any viable product released. Of the many sensor modalities tried, the combination of electrical and optical measurement is among the most promising for continuous measurements. Although non-invasive prediction of exact glucose levels may seem futile, prediction of their trends may be useful for certain applications. Hypoglycemia is the most serious of the acute complications in type-1 diabetes highlighting the need for a reliable alarm, but little is known about the performance of this technology in predicting hypoglycemic glucose levels and associated trends. We aimed to assess such performance on the way to develop a multisensor system for detection of hypoglycemia, based on near-infrared (NIR), bioimpedance and skin temperature measurements taken during hypoglycemic and euglycemic glucose clamps in 20 subjects with type-1 diabetes. Performance of blood glucose prediction was assessed by global partial least squares and neural network regression models using repeated double cross-validation. Best trend prediction was obtained by including all measurements in a neural network model. Prediction of glucose level was inaccurate for threshold-based detection of hypoglycemia, but the trend predictions may provide useful information in a multisensor system. Comparing NIR and bioimpedance measurements, NIR seems to be the main predictor of blood glucose while bioimpedance may act as correction for individual confounding properties.

Soluble Leptin Receptor Predicts Insulin Sensitivity and Correlates With Upregulation of Metabolic Pathways in Men.

Context: Plasma soluble leptin receptor (sOb-R) seems protective of gestational and type 2 diabetes in observational studies, but the mechanisms are unknown. sOb-R is formed by ectodomain shedding of membrane-bound leptin receptors (Ob-Rs), but its associations with messenger RNA (mRNA) expression are scarcely explored. Objective: To explore associations between plasma levels of sOb-R and (1) insulin sensitivity, (2) mRNA pathways in adipose tissue and skeletal muscle, and (3) mRNA of candidate genes for sOb-R generation in adipose tissue and skeletal muscle. Design and Participants: The MyoGlu study included 26 sedentary, middle-aged men who underwent a 12-week intensive exercise intervention. We measured plasma sOb-R with enzyme-linked immunosorbent assay, insulin sensitivity with a hyperinsulinemic euglycemic clamp, and mRNA in skeletal muscle and adipose tissue with high-throughput sequencing. Results: Baseline plasma sOb-R was strongly associated with baseline glucose infusion rate (GIR) [ß (95% confidence interval), 1.19 (0.57 to 1.82) mg/kg/min, P = 0.0006] and GIR improvement after the exercise intervention [0.58 (0.03 to 1.12) mg/kg/min, P = 0.039], also independently of covariates, including plasma leptin. In pathway analyses, high plasma sOb-R correlated with upregulation of metabolic pathways and downregulation of inflammatory pathways in both adipose tissue and skeletal muscle. In skeletal muscle, mRNA of LEPROT and LEPROTL1 (involved in Ob-R cell surface expression) and ADAM10 and ADAM17 (involved sOb-R-shedding) increased after the exercise intervention. Conclusions: Higher plasma sOb-R was associated with improved GIR, upregulation of metabolic pathways, and downregulation of inflammatory pathways, which may be possible mechanisms for the seemingly protective effect of plasma sOb-R on subsequent risk of gestational and type 2 diabetes found in observational studies.

Long-term follow-up of a hospital-based, multi-intervention programme in type 2 diabetes mellitus: impact on cardiovascular events and death.

Objective To report the long-term impact on cardiovascular (CV) outcomes and mortality of a 2-year hospital-based multi-interventional care programme as compared with general practitioner (GP)-provided standard care. Methods Patients with type 2 diabetes with ≥ 1 additional CV risk factor were randomized to 2 years of specialist-based, multi-intervention comprising lifestyle modification and specific pharmacological treatment, or GP-based standard care. After the 2-year intervention period, all participants returned to pre-study care, but were followed up for CV outcomes and mortality. The primary outcome was time to any first severe CV event or death. Results A total of 120 patients (31 women) were enrolled in the study. During the mean ± SD observational period of 8.7 ± 2.0 years, 27 patients (16 and 11 in the multi-intervention and standard care groups, respectively) experienced at least one primary outcome event, with a hazard ratio (HR) if allocated to the multi-intervention group of 1.73 (95% confidence interval (CI) 0.80, 3.75). The HR for total mortality was 1.82 (95% CI 0.66, 5.01). Conclusions Hospital-based multi-intervention in patients with type 2 diabetes mellitus improved long-term glycaemic control, but failed to reduce CV outcomes and deaths. Clinical trials.gov id: NCT00133718.

Soluble Leptin Receptor and Risk of Gestational Diabetes in a Multiethnic Population: A Prospective Cohort Study.

CONTEXT: Soluble leptin receptor (sOb-R), a potential marker of leptin resistance, is inversely associated with risk of type 2 diabetes, independently of leptin concentrations. We have previously shown that ethnic difference in leptin concentration may partly explain the increased risk of gestational diabetes (GDM) in South Asians. OBJECTIVE: Our objective was to investigate whether sOb-R concentrations are associated with risk of GDM, whether concentrations of sOb-R differ across ethnic groups, and whether ethnic differences in sOb-R explain the ethnic differences in GDM risk. DESIGN AND SETTING: The STORK Groruddalen study; a prospective cohort study of pregnant women living in Oslo, Norway, between May 2008 and May 2010. PARTICIPANTS: Of the total sample (n = 823), 680 (47.1% Europeans) had sOb-R measured in pregnancy week 15 and an oral glucose tolerance test performed in week 28. MAIN OUTCOME MEASURE: GDM was diagnosed according to World Health Organization 2013 criteria. RESULTS: sOb-R was inversely associated with GDM (odds ratio, 0.76 [95% confidence interval, 0.69-0.83] per ng/ml increase in sOb-R, P < .001) in crude analysis. The association was attenuated after adjustments for covariates and leptin (0.85 [0.77-0.95], P = .004). Compared to women with sOb-R higher than 5 ng/ml, the odds ratio of GDM was 0.29(0.11-0.78; P = .014) among women with sOb-R greater than 10 ng/ml and 0.59 (0.37-0.94; P = .026) among women with sOb-R 5-10 ng/ml, in adjusted analysis. sOb-R levels did not differ across ethnic groups, and sOb-R did not explain ethnic differences in GDM risk. CONCLUSIONS: There was an independent, inverse association between sOb-R and GDM, with the lowest risk of GDM observed among higher sOb-R concentrations.

Insulin sensitivity, body composition and adipose depots following 12 w combined endurance and strength training in dysglycemic and normoglycemic sedentary men.

CONTEXT: Insulin resistance and dysglycemia are associated with physical inactivity and adiposity, and may be improved by exercise. OBJECTIVE: Investigate the effect of exercise on insulin sensitivity, body composition and adipose depots in sedentary men with (n = 11) or without (n = 11) overweight and dysglycemia. MATERIAL AND METHODS: Euglycemic-hyperinsulinemic clamp, ankle-to-neck MRI, MRS, muscle and adipose tissue biopsies before and after 12 weeks combined strength and endurance exercise. RESULTS: Insulin sensitivity, VO2max, strength, whole-body and muscle fat content, and abdominal adipose depots were improved without obvious differences between normo- and dysglycemic men. Hepatic fat, waist circumference and subcutaneous adipose tissue were reduced in the dysglycemic group. For both groups plasma adiponectin was reduced, whereas IL-6 was unchanged. Visceral fat was preferentially lost compared with other adipose depots. DISCUSSION AND CONCLUSION: Body composition, fat distribution and insulin sensitivity improved following training in sedentary middle-aged men with and without dysglycemia.

Effects of early pregnancy BMI, mid-gestational weight gain, glucose and lipid levels in pregnancy on offspring's birth weight and subcutaneous fat: a population-based cohort study.

BACKGROUND: Maternal glucose and lipid levels are associated with neonatal anthropometry of the offspring, also independently of maternal body mass index (BMI). Gestational weight gain, however, is often not accounted for. The objective was to explore whether the effects of maternal glucose and lipid levels on offspring's birth weight and subcutaneous fat were independent of early pregnancy BMI and mid-gestational weight gain. METHODS: In a population-based, multi-ethnic, prospective cohort of 699 women and their offspring, maternal anthropometrics were collected in gestational week 15 and 28. Maternal fasting plasma lipids, fasting and 2-hour glucose post 75 g glucose load, were collected in gestational week 28. Maternal risk factors were standardized using z-scores. Outcomes were neonatal birth weight and sum of skinfolds in four different regions. RESULTS: Mean (standard deviation) birth weight was 3491 ± 498 g and mean sum of skinfolds was 18.2 ± 3.9 mm. Maternal fasting glucose and HDL-cholesterol were predictors of birth weight, and fasting and 2-hour glucose were predictors of neonatal sum of skinfolds, independently of weight gain as well as early pregnancy BMI, gestational week at inclusion, maternal age, parity, smoking status, ethnic origin, gestational age and offspring's sex. However, weight gain was the strongest independent predictor of both birth weight and neonatal sum of skinfolds, with a 0.21 kg/week increased weight gain giving a 110.7 (95% confidence interval 76.6-144.9) g heavier neonate, and with 0.72 (0.38-1.06) mm larger sum of skinfolds. The effect size of mother's early pregnancy BMI on birth weight was higher in non-Europeans than in Europeans. CONCLUSIONS: Maternal fasting glucose and HDL-cholesterol were predictors of offspring's birth weight, and fasting and 2-hour glucose were predictors of neonatal sum of skinfolds, independently of weight gain. Mid-gestational weight gain was a stronger predictor of both birth weight and neonatal sum of skinfolds than early pregnancy BMI, maternal glucose and lipid levels.

The effects of acute and chronic exercise on PGC-1α, irisin and browning of subcutaneous adipose tissue in humans.

Irisin was first identified as a peroxisome proliferator-activated receptor γ co-activator-1α (PGC-1α) dependent myokine with the potential to induce murine brown-fat-like development of white adipose tissue. In humans, the regulatory effect of training on muscle FNDC5 mRNA expression and subsequently irisin levels in plasma is more controversial. We recruited 26 inactive men (13 normoglycaemic and normal weight, controls; and 13 slightly hyperglycaemic and overweight, pre-diabetes group) aged 40-65 years for a 12-week intervention of combined endurance and strength training with four sessions of training per week. Before and after the 12-week intervention period, participants were exposed to an acute endurance workload of 45 min at 70% of VO(2max), and muscle biopsies were taken prior to and after exercise. Skeletal muscle mRNA for PGC1A and FNDC5 correlated and both PGC1A and FNDC5 mRNA levels increased after 12 weeks of training in both control and pre-diabetes subjects. Circulating irisin was reduced in response to 12 weeks of training, and was increased acutely (~1.2-fold) just after acute exercise. Plasma concentration of irisin was higher in pre-diabetes subjects compared with controls. There was little effect of 12 weeks of training on selected browning genes in subcutaneous adipose tissue. UCP1 mRNA did not correlate with FNDC5 expression in subcutaneous adipose tissue or skeletal muscle or with irisin levels in plasma. We observed no enhancing effect of long-term training on circulating irisin levels, and little or no effect of training on browning of subcutaneous white adipose tissue in humans.

Characteristics of glucose metabolism in Nordic and South Asian subjects with type 2 diabetes.

BACKGROUND: Insulin resistance and type 2 diabetes are more prevalent in people of South Asian ethnicity than in people of Western European origin. To investigate the source of these differences, we compared insulin sensitivity, insulin secretion, glucose and lipid metabolism in South Asian and Nordic subjects with type 2 diabetes. METHODS: Forty-three Nordic and 19 South Asian subjects with type 2 diabetes were examined with intra-venous glucose tolerance test, euglycemic clamp including measurement of endogenous glucose production, indirect calorimetry measuring glucose and lipid oxidation, and dual x-ray absorptiometry measuring body composition. RESULTS: Despite younger mean ± SD age (49.7 ± 9.4 vs 58.3 ± 8.3 years, p = 0.001), subjects of South Asian ethnicity had the same diabetes duration (9.3 ± 5.5 vs 9.6 ± 7.0 years, p = 0.86), significantly higher median [inter-quartile range] HbA1c (8.5 [1.6] vs 7.3 [1.6] %, p = 0.024) and lower BMI (28.7 ± 4.0 vs 33.2 ± 4.7 kg/m(2), p<0.001). The South Asian group exhibited significantly higher basal endogenous glucose production (19.1 [9.1] vs 14.4 [6.8] µmol/kgFFM · min, p = 0.003). There were no significant differences between the groups in total glucose disposal (39.1 ± 20.4 vs 39.2 ± 17.6 µmol/kgFFM · min, p = 0.99) or first phase insulin secretion (AUC0-8 min: 220 [302] vs 124 [275] pM, p = 0.35). In South Asian subjects there was a tendency towards positive correlations between endogenous glucose production and resting and clamp energy expenditure. CONCLUSIONS: Subjects of South Asian ethnicity with type 2 diabetes, despite being younger and leaner, had higher basal endogenous glucose production, indicating higher hepatic insulin resistance, and a trend towards higher use of carbohydrates as fasting energy substrate compared to Nordic subjects. These findings may contribute to the understanding of the observed differences in prevalence of type 2 diabetes between the ethnic groups.

Diabetes susceptibility in ethnic minority groups from Turkey, Vietnam, Sri Lanka and Pakistan compared with Norwegians - the association with adiposity is strongest for ethnic minority women.

BACKGROUND: The difference in diabetes susceptibility by ethnic background is poorly understood. The aim of this study was to assess the association between adiposity and diabetes in four ethnic minority groups compared with Norwegians, and take into account confounding by socioeconomic position. METHODS: Data from questionnaires, physical examinations and serum samples were analysed for 30-to 60-year-olds from population-based cross-sectional surveys of Norwegians and four immigrant groups, comprising 4110 subjects born in Norway (n = 1871), Turkey (n = 387), Vietnam (n = 553), Sri Lanka (n = 879) and Pakistan (n = 420). Known and screening-detected diabetes cases were identified. The adiposity measures BMI, waist circumference and waist-hip ratio (WHR) were categorized into levels of adiposity. Gender-specific logistic regression models were applied to estimate the risk of diabetes for the ethnic minority groups adjusted for adiposity and income-generating work, years of education and body height used as a proxy for childhood socioeconomic position. RESULTS: The age standardized diabetes prevalence differed significantly between the ethnic groups (women/men): Pakistan: 26.4% (95% CI 20.1-32.7)/20.0% (14.9-25.2); Sri Lanka: 22.5% (18.1-26.9)/20.7% (17.3-24.2), Turkey: 11.9% (7.2-16.7)/12.0% (7.6-16.4), Vietnam: 8.1% (5.1-11.2)/10.4% (6.6-14.1) and Norway: 2.7% (1.8-3.7)/6.4% (4.6-8.1). The prevalence increased more in the minority groups than in Norwegians with increasing levels of BMI, WHR and waist circumference, and most for women. Highly significant ethnic differences in the age-standardized prevalence of diabetes were found for both genders in all categories of all adiposity measures (p < 0.001). The Odds Ratio (OR) for diabetes adjusted for age, WHR, body height, education and income-generating work with Norwegians as reference was 2.9 (1.30-6.36) for Turkish, 2.7 (1.29-5.76) for Vietnamese, 8.0 (4.19-15.14) for Sri Lankan and 8.3 (4.37-15.58) for Pakistani women. Men from Sri Lanka and Pakistan had identical ORs (3.0 (1.80-5.12)). CONCLUSIONS: A high prevalence of diabetes was found in 30-to 60-year-olds from ethnic minority groups in Oslo, with those from Sri Lanka and Pakistan at highest risk. For all levels of adiposity, a higher susceptibility for diabetes was observed for ethnic minority groups compared with Norwegians. The association persisted after adjustment for socioeconomic position for all minority women and for men from Sri Lanka and Pakistan.