Lifetime and 10-year cardiovascular risk prediction in individuals with type 1 diabetes: The LIFE-T1D model.

AIMS: To develop and externally validate the LIFE-T1D model for the estimation of lifetime and 10-year risk of cardiovascular disease (CVD) in individuals with type 1 diabetes. MATERIALS AND METHODS: A sex-specific competing risk-adjusted Cox proportional hazards model was derived in individuals with type 1 diabetes without prior CVD from the Swedish National Diabetes Register (NDR), using age as the time axis. Predictors included age at diabetes onset, smoking status, body mass index, systolic blood pressure, glycated haemoglobin level, estimated glomerular filtration rate, non-high-density lipoprotein cholesterol, albuminuria and retinopathy. The model was externally validated in the Danish Funen Diabetes Database (FDDB) and the UK Biobank. RESULTS: During a median follow-up of 11.8 years (interquartile interval 6.1-17.1 years), 4608 CVD events and 1316 non-CVD deaths were observed in the NDR (n = 39 756). The internal validation c-statistic was 0.85 (95% confidence interval [CI] 0.84-0.85) and the external validation c-statistics were 0.77 (95% CI 0.74-0.81) for the FDDB (n = 2709) and 0.73 (95% CI 0.70-0.77) for the UK Biobank (n = 1022). Predicted risks were consistent with the observed incidence in the derivation and both validation cohorts. CONCLUSIONS: The LIFE-T1D model can estimate lifetime risk of CVD and CVD-free life expectancy in individuals with type 1 diabetes without previous CVD. This model can facilitate individualized CVD prevention among individuals with type 1 diabetes. Validation in additional cohorts will improve future clinical implementation.

Low-grade inflammation in persons with recently diagnosed type 2 diabetes: The role of abdominal adiposity and putative mediators.

AIMS: To determine the magnitude of the association between abdominal adiposity and low-grade inflammation in persons with recently diagnosed type 2 diabetes (T2D) and to determine to what extent this association is mediated by low physical activity level, hyperinsulinaemia, hyperglycaemia, dyslipidaemia, hypertension, and comorbidities. MATERIALS AND METHODS: We measured waist circumference, clinical characteristics, and inflammatory markers i.e. tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and high-sensitivity C-reactive protein (hsCRP), in >9000 persons with recently diagnosed T2D. We applied multiple mediation analysis using structural equation modelling, with adjustment for age and sex. RESULTS: Waist circumference as a proxy for abdominal adiposity was positively associated with all inflammatory markers. Hence, a one-standard deviation (SD) increase in waist circumference (SD = 15 cm) was associated with a 22%, 35%, and 46% SD increase in TNF-α (SD = 1.5 pg/mL), IL-6 (SD = 4.4 pg/mL), and hsCRP (SD = 6.9 mg/L), respectively. The level of hyperinsulinaemia assessed by fasting C-peptide was quantitatively the most important mediator, accounting for 9%-25% of the association between abdominal adiposity and low-grade inflammation, followed by low physical activity (5%-7%) and high triglyceride levels (2%-6%). Although mediation of adiposity-induced inflammation by greater comorbidity and higher glycated haemoglobin levels reached statistical significance, their impact was minor (1%-2%). CONCLUSIONS: In persons with recently diagnosed T2D, there was a clear association between abdominal adiposity and low-grade inflammation. A considerable part (20%-40%) of this association was mediated by other factors, with hyperinsulinaemia as a potentially important driver of adiposity-induced inflammation in T2D.

A six-month low-carbohydrate diet high in fat does not adversely affect endothelial function or markers of low-grade inflammation in patients with type 2 diabetes: an open-label randomized controlled trial.

BACKGROUND: While a low-carbohydrate diet (LCD) reduces HbA1c in patients with type 2 diabetes (T2D), the associated high intake of fat may adversely affect cardiovascular risk factors. To address this, we examined the effect of a non-calorie-restricted LCD high in fat on endothelial function and markers of low-grade inflammation in T2D over 6 months. METHODS: In an open-label randomized controlled trial, 71 patients with T2D were randomized 2:1 to either a LCD (< 20 E% carbohydrates, 50-60 E% fat) or a control diet (50-60 E% carbohydrates, 20-30 E% fat) for six months. Flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID) were assessed by ultrasound in the brachial artery together with plasma interleukin-6 (IL-6) and serum high-sensitivity C-reactive protein (hsCRP) in the participants at baseline (n = 70) and after six months (n = 64). RESULTS: The FMD and NID were unaltered in both groups after six months, and there were no between-group differences in change of either FMD (p = 0.34) or NID (p = 0.53) in response to the interventions. The circulating hsCRP and IL-6 levels decreased only in response to LCD (both p < 0.05). However, comparing changes over time with the control diet, the LCD did not reduce either IL-6 (p = 0.25) or hsCRP (p = 0.07) levels. The lack of changes in FMD and NID in response to LCD persisted after adjustment for cardiovascular risk factors. CONCLUSION: A LCD high in fat for six months does not adversely affect endothelial function or selected markers of low-grade inflammation, which suggests that this nutritional approach does not increase the risk of cardiovascular disease. Trial registration ClinicalTrials.gov (NCT03068078).

Bariatric surgery in individuals with type 2 diabetes is not associated with short or long-term risk of diabetic retinopathy progression: results from a nationwide cohort study.

AIMS: Bariatric surgery is used to induce weight loss and glycemic stability in type 2 diabetes (T2D). It has been a concern that this may lead to early worsening of diabetic retinopathy (DR) due to a rapid decline in HbA1c. In this study, we evaluated the risk of short and long-term DR development and need for ocular intervention in an entire nation of individuals with T2D undergoing bariatric surgery. METHODS: The study comprised a national, register-based cohort of individuals with T2D screened for DR. Cases were matched by age, sex and DR level at the date of surgery (index date) with non-bariatric controls. We extracted information on DR levels, in- and outpatient treatments, pharmaceutical prescriptions and laboratory values. We evaluated worsening of DR (incident and progressive DR) at follow-up (6 and 36 months). RESULTS: Amongst 238,967 individuals with T2D, who attended diabetic eye screening, we identified 553 that underwent bariatric surgery (0.2%) and 2677 non-bariatric controls. Median age was 49 years, and 63% were female. Cases had more comorbidities, lower HbA1c as well as more frequent use of glucose-lowering and antihypertensive medication than controls at index date. In a fully adjusted logistic regression model, the risk of DR worsening for cases was not significantly different compared to controls, neither short-term (OR 0.41 [CI 95% 0.13; 1.33], p = 0.14) nor long-term (OR 0.64 [CI 95% 0.33; 1.24], p = 0.18). CONCLUSIONS: In this nationwide study, bariatric surgery did not associate with increased risk of short- or long-term DR worsening.

The Rho guanine dissociation inhibitor α inhibits skeletal muscle Rac1 activity and insulin action.

The molecular events governing skeletal muscle glucose uptake have pharmacological potential for managing insulin resistance in conditions such as obesity, diabetes, and cancer. With no current pharmacological treatments to target skeletal muscle insulin sensitivity, there is an unmet need to identify the molecular mechanisms that control insulin sensitivity in skeletal muscle. Here, the Rho guanine dissociation inhibitor α (RhoGDIα) is identified as a point of control in the regulation of insulin sensitivity. In skeletal muscle cells, RhoGDIα interacted with, and thereby inhibited, the Rho GTPase Rac1. In response to insulin, RhoGDIα was phosphorylated at S101 and Rac1 dissociated from RhoGDIα to facilitate skeletal muscle GLUT4 translocation. Accordingly, siRNA-mediated RhoGDIα depletion increased Rac1 activity and elevated GLUT4 translocation. Consistent with RhoGDIα's inhibitory effect, rAAV-mediated RhoGDIα overexpression in mouse muscle decreased insulin-stimulated glucose uptake and was detrimental to whole-body glucose tolerance. Aligning with RhoGDIα's negative role in insulin sensitivity, RhoGDIα protein content was elevated in skeletal muscle from insulin-resistant patients with type 2 diabetes. These data identify RhoGDIα as a clinically relevant controller of skeletal muscle insulin sensitivity and whole-body glucose homeostasis, mechanistically by modulating Rac1 activity.

Inter-grader reliability in the Danish screening programme for diabetic retinopathy.

PURPOSE: The Danish Registry of Diabetic Retinopathy includes information from >200 000 patients who attends diabetic retinopathy (DR) screening in Denmark. Screening of patients with uncomplicated type 2 diabetes is often performed by practicing ophthalmologists, while patients with type 1 and complicated type 2 diabetes attends screening at hospitals. We performed a clinical reliability study of retinal images from Danish screening facilities to explore the inter-grader agreement between the primary screening ophthalmologist and a blinded, certified grader. METHODS: Invitations to participate were sent to screening facilities across Denmark. The primary grader uploaded fundus photographs with information on estimated level of DR (International Clinical Diabetic Retinopathy scale as 0 [no DR], 1-3 [mild, moderate or severe nonproliferative DR {NPDR}], or 4 [proliferative DR {PDR}]), region of screening, image style, and screening facility. Images were then regraded by a blinded, certified, secondary grader. Weighted kappa analysis was performed to evaluate agreement. RESULTS: Fundus photographs from 230 patients (458 eyes) were received from practicing ophthalmologists (52.6%) and hospital-based grading centres (47.4%) from all Danish regions. Reported levels of DR by the primary graders were 66.8%, 12.2%, 13.1%, 1.3% and 5.5% for DR levels 0-4. The overall agreement between primary and secondary graders was 93% (κ = 0.83). Based on screening facility agreement was 96% (κ = 0.89) and 90% (κ = 0.76) for practicing ophthalmologists and hospital-based graders. CONCLUSION: In this nationwide study, we observed a high overall inter-grader agreement and based on this, it is reasonable to assume that reported DR gradings in the screening programme in Denmark, accurately reflect the truth.

Physician-led in-hospital multidisciplinary team conferences with multiple medical specialities present - A scoping review.

Introduction: Multidisciplinary Team Conferences (MDTs) are complex interventions in the modern healthcare system and they promote a model of coordinated patient care and management. However, MDTs within chronic diseases are poorly defined. Therefore, the aim of this scoping review was to summarise the current literature on physician-led in-hospital MDTs in chronic non-malignant diseases. Method: Following the PRISMA-ScR guideline for scoping reviews, a search on MDT interventions in adult patients, with three or more medical specialties represented, was performed. Results: We identified 2790 studies, from which 8 studies were included. The majority of studies were non-randomised and focused on a single disease entity such as infective endocarditis, atrial fibrillation, IgG4-related disease, or arterial and venous thrombosis. The main reason for referral was confirmation or establishment of a diagnosis, and the MDT members were primarily from medical specialties gathered especially for the MDT. Outcomes of the included studies were grouped into process indicators and outcome indicators. Process indicators included changes in diagnostic confirmation as well as therapeutic strategy and management. All studies reporting process indicators demonstrated significant changes before and after the MDT. Conclusion: MDTs within chronic diseases appeared highly heterogeneous with respect to structure, reasons for referral, and choice of outcomes. While process indicators, such as change in diagnosis, and treatment management/plan seem improved, such have not been demonstrated through outcome indicators.

Accelerometer-derived physical activity and sedentary behaviors in individuals with newly diagnosed type 2 diabetes: A cross-sectional study from the Danish nationwide DD2 cohort.

Introduction: Habitual physical activity behaviors of individuals with new-onset type 2 diabetes are largely unknown. We aimed to investigate accelerometer-derived physical activity behaviors in individuals with newly diagnosed type 2 diabetes. We also examined sociodemographic and health-related correlates of a high-risk physical activity profile. Methods: This cross-sectional study used data from 768 participants enrolled in an intervention study nested within the Danish Centre for Strategic Research in Type 2 diabetes (DD2) cohort. Physical activity was assessed by 24-h dual monitor accelerometry. Prevalence ratios of having a high-risk physical activity profile were estimated using Poisson regression adjusted for age and sex. Results: Study participants spent on average 9.7 (25th and 75th percentiles, 8.3; 11.1) hours/day sitting, walked for 1.1 (0.8; 1.6) hours/day and accumulated 4,000 (2,521; 5,864) steps/day. Still, 62% met the recommendations for physical activity. Characteristics associated with a high-risk physical activity profile (observed in 24.5% of participants) included older age, higher body mass index (BMI), unemployment, retirement, comorbidities, and current smoking. Hence, participants aged 60-69, 70-79 and 80+ years had prevalence ratios of 2.12 (95% CI 1.31; 3.42), 1.99 (1.18; 3.34) and 3.09 (1.42; 6.75) for a high-risk activity profile, respectively, versus participants <50 years. BMI values of 30-39 and 40+ were associated with 1.83 (1.06; 3.15) and 3.38 (1.88; 6.05) higher prevalence ratios compared to normal-weight. Unemployment or retirement was associated with 1.62 (1.09; 2.41) and 2.15 (1.37; 3.39) times higher prevalence ratios, compared to individuals in the working force. Having a Charlson Comorbidity Index score of 1-2 or 3+ was associated with 1.36 (1.03-1.79) and 1.90 (1.27-1.84) higher prevalence ratios, while current smoking was associated with a prevalence ratio of 1.72 (1.25; 2.35) compared to never smokers. Conclusion: This study shows that 62% of individuals with newly diagnosed type 2 diabetes met the recommendations for physical activity. Still, the majority of participants were also highly sedentary and accumulated very few daily steps, emphasizing the need for focusing on both increasing physical activity and reducing sedentary behaviors in the prevention of diabetes-related complications. Individuals with a high-risk physical activity profile were characterized by more obesity, socioeconomic inequalities, advanced age and comorbidities.Trial registration number: NCT02015130.

Effects of Delayed-Release Olive Oil and Hydrolyzed Pine Nut Oil on Glucose Tolerance, Incretin Secretion and Appetite in Humans.

BACKGROUND: To investigate the potential synergistic effects of olive oil releasing 2-oleoylglycerol and hydrolyzed pine nut oil containing 20% pinolenic acid on GLP-1 secretion, glucose tolerance, insulin secretion and appetite in healthy individuals, when delivered to the small intestine as potential agonists of GPR119, FFA1 and FFA4. METHODS: Nine overweight/obese individuals completed three 6-h oral glucose tolerance tests (OGTTs) in a crossover design. At -30 min, participants consumed either: no oil, 6 g of hydrolyzed pine nut oil (PNO-FFA), or a combination of 3 g hydrolyzed pine nut oil and 3 g olive oil (PNO-OO) in delayed-release capsules. Repeated measures of glucose, insulin, C-peptide, GLP-1, GIP, ghrelin, subjective appetite and gastrointestinal tolerability were done. RESULTS: PNO-FFA augmented GLP-1 secretion from 0-360 min compared to no oil and PNO-OO (p < 0.01). GIP secretion was increased from 240-360 min after both PNO-FFA and PNO-OO versus no oil (p < 0.01). Both oil treatments suppressed subjective appetite by reducing hunger and prospective food consumption and increasing satiety (p < 0.05). CONCLUSIONS: In support of previous findings, 6 g of delayed-release hydrolyzed pine nut oil enhanced postprandial GLP-1 secretion and reduced appetite. However, no synergistic effect of combining hydrolyzed pine nut oil and olive oil on GLP-1 secretion was observed. These results need further evaluation in long-term studies including effects on bodyweight and insulin sensitivity.

Acute effects of delayed-release hydrolyzed pine nut oil on glucose tolerance, incretins, ghrelin and appetite in healthy humans.

BACGROUND & AIM: Pinolenic acid, a major component (~20%) of pine nut oil, is a dual agonist of the free fatty acid receptors, FFA1 and FFA4, which may regulate release of incretins and ghrelin from the gut. Here, we investigated the acute effects of hydrolyzed pine nut oil (PNO-FFA), delivered to the small intestine by delayed-release capsules, on glucose tolerance, insulin, incretin and ghrelin secretion, and appetite. METHODS: In two cross-over studies, we evaluated 3 g unhydrolyzed pine nut oil (PNO-TG) or 3 g PNO-FFA versus no oil in eight healthy, non-obese subjects (study 1), and 3 g PNO-FFA or 6 g PNO-FFA versus no oil in ten healthy, overweight/obese subjects (study 2) in both studies given in delayed-release capsules 30 min prior to a 4-h-oral glucose tolerance test (OGTT). Outcomes were circulating levels of glucose, insulin, GLP-1, GIP, ghrelin, appetite and gastrointestinal tolerability during OGTT. RESULTS: Both 3 g PNO-FFA in study 1 and 6 g PNO-FFA in study 2 markedly increased GLP-1 levels (p < 0.001) and attenuated ghrelin levels (p < 0.001) during the last 2 h of the OGTT compared with no oil. In study 2, these effects of PNO-FFA were accompanied by an increased satiety and fullness (p < 0.03), and decreased prospective food consumption (p < 0.05). PNO-FFA caused only small reductions in glucose and insulin levels during the first 2 h of the OGTT. CONCLUSIONS: Our results provide evidence that PNO-FFA delivered to the small intestine by delayed-release capsules may reduce appetite by augmenting GLP-1 release and attenuating ghrelin secretion in the late postprandial state. CLINICAL TRIAL REGISTRY NUMBERS: NCT03062592 and NCT03305367.

Circulating Follistatin and Activin A and Their Regulation by Insulin in Obesity and Type 2 Diabetes.

BACKGROUND: Circulating follistatin (Fst) binds activin A and thereby regulates biological functions such as muscle growth and ß-cell survival. However, Fst and activin A's implication in metabolic regulation is unclear. OBJECTIVE: To investigate circulating Fst and activin A in obesity and type 2 diabetes (T2D) and determine their association with metabolic parameters. Further, to examine regulation of Fst and activin A by insulin and the influence of obesity and T2D hereon. METHODS: Plasma Fst and activin A levels were analyzed in obese T2D patients (N = 10) closely matched to glucose-tolerant lean (N = 12) and obese (N = 10) individuals in the fasted state and following a 4-h hyperinsulinemic-euglycemic clamp (40 mU·m-2·min-1) combined with indirect calorimetry. RESULTS: Circulating Fst was ~30% higher in patients with T2D compared with both lean and obese nondiabetic individuals (P < .001), while plasma activin A was unaltered. In the total cohort, fasting plasma Fst correlated positively with fasting plasma glucose, serum insulin and C-peptide levels, homeostasis model assessment of insulin resistance, and hepatic and adipose tissue insulin resistance after adjusting for age, gender and group (all r > 0.47; P < .05). However, in the individual groups these correlations only achieved significance in patients with T2D (not plasma glucose). Acute hyperinsulinemia at euglycemia reduced circulating Fst by ~30% (P < .001) and this response was intact in patients with T2D. Insulin inhibited FST expression in human hepatocytes after 2 h and even further after 48 h. CONCLUSIONS: Elevated circulating Fst, but not activin A, is strongly associated with measures of insulin resistance in patients with T2D. However, the ability of insulin to suppress circulating Fst is preserved in T2D.

In human nephrectomy specimens, the kidney level of tubular transport proteins does not correlate with their abundance in urinary extracellular vesicles.

Human urinary extracellular vesicles (uEVs) contain proteins from all nephron segments. An assumption for years has been that uEVs might provide a noninvasive liquid biopsy that reflect physiological regulation of transporter protein expression in humans. We hypothesized that protein abundance in human kidney tissue and uEVs are directly related and tested this in paired collections of nephrectomy tissue and urine sample from 12 patients. Kidney tissue was fractioned into total kidney protein, crude membrane (plasma membrane and large intracellular vesicles)-enriched, and intracellular vesicle-enriched fractions as well as sections for immunolabeling. uEVs were isolated from spot urine samples. Antibodies were used to quantify six segment-specific proteins [proximal tubule-expressed Na+-phosphate cotransporters (NaPi-2a), thick ascending limb-expressed Tamm-Horsfall protein and renal outer medullary K+ channels, distal convoluted tubule-expressed NaCl cotransporters, intercalated cell-expressed V-type H+-ATPase subunit G3 (ATP6V1G3), and principal cell-expressed aquaporin 2] and three uEV markers (exosomal CD63, microvesicle marker vesicle-associated membrane protein 3, and ß-actin) in each fraction. By Western blot analysis and immunofluorescence labeling, we found significant positive correlations between the abundance of CD63, NaCl cotransporters, aquaporin 2, and ATP6V1G3, respectively, within the different kidney-derived fractions. We detected all nine proteins in uEVs, but their level did not correlate with kidney tissue protein abundance. uEV protein levels showed higher interpatient variability than kidney-derived fractions, indicating that factors, besides kidney protein abundance, contribute to the uEV protein level. Our data suggest that, in a random sample of nephrectomy patients, uEV protein level is not a predictor of kidney protein abundance.

Obesity-Associated Hypermetabolism and Accelerated Senescence of Bone Marrow Stromal Stem Cells Suggest a Potential Mechanism for Bone Fragility.

Obesity is associated with increased risk for fragility fractures. However, the cellular mechanisms are unknown. Using a translational approach combining RNA sequencing and cellular analyses, we investigated bone marrow stromal stem cells (BM-MSCs) of 54 men divided into lean, overweight, and obese groups on the basis of BMI. Compared with BM-MSCs obtained from lean, obese BM-MSCs exhibited a shift of molecular phenotype toward committed adipocytic progenitors and increased expression of metabolic genes involved in glycolytic and oxidoreductase activity. Interestingly, compared with paired samples of peripheral adipose tissue-derived stromal cells (AT-MSCs), insulin signaling of obese BM-MSCs was enhanced and accompanied by increased abundance of insulin receptor positive (IR+) and leptin receptor positive (LEPR+) cells in BM-MSC cultures. Their hyper-activated metabolic state was accompanied by an accelerated senescence phenotype. Our data provide a plausible explanation for the bone fragility in obesity caused by enhanced insulin signaling leading to accelerated metabolic senescence of BM-MSCs.

Acute Exercise Increases Plasma Levels of Muscle-Derived Microvesicles Carrying Fatty Acid Transport Proteins.

CONTEXT: Microvesicles (MVs) are a class of membrane particles shed by any cell in the body in physiological and pathological conditions. They are considered to be key players in intercellular communication, and with a molecular content reflecting the composition of the cell of origin, they have recently emerged as a promising source of biomarkers in a number of diseases. OBJECTIVE: The effects of acute exercise on the plasma concentration of skeletal muscle-derived MVs (SkMVs) carrying metabolically important membrane proteins were examined. PARTICIPANTS: Thirteen men with obesity and type 2 diabetes mellitus (T2DM) and 14 healthy male controls with obesity exercised on a cycle ergometer for 60 minutes. INTERVENTIONS: Muscle biopsies and blood samples-obtained before exercise, immediately after exercise, and 3 hours into recovery-were collected for the analysis of long-chain fatty acid (LCFA) transport proteins CD36 (a scavenger receptor class B protein) and fatty acid transport protein 4 (FATP4) mRNA content in muscle and for flow cytometric studies on circulating SkMVs carrying either LCFA transport protein. RESULTS: Besides establishing a flow cytometric approach for the detection of circulating SkMVs and subpopulations carrying either CD36 or FATP4 and thereby adding proof to their existence, we demonstrated an overall exercise-induced change of SkMVs carrying these LCFA transport proteins. A positive correlation between exercise-induced changes in skeletal muscle CD36 mRNA expression and concentrations of SkMVs carrying CD36 was found in T2DM only. CONCLUSIONS: This approach could add important real-time information about the abundance of LCFA transport proteins present on activated muscle cells in subjects with impaired glucose metabolism.

Transcriptional and Epigenetic Changes Influencing Skeletal Muscle Metabolism in Women With Polycystic Ovary Syndrome.

Context: Insulin resistance in skeletal muscle is a major risk factor for the development of type 2 diabetes in women with polycystic ovary syndrome (PCOS). Despite this, the mechanisms underlying insulin resistance in PCOS are largely unknown. Objective: To investigate the genome-wide DNA methylation and gene expression patterns in skeletal muscle from women with PCOS and controls and relate them to phenotypic variations. Design/Participants: In a case-control study, skeletal muscle biopsies from women with PCOS (n = 17) and age-, weight-, and body mass index‒matched controls (n = 14) were analyzed by array-based DNA methylation and mRNA expression profiling. Results: Eighty-five unique transcripts were differentially expressed in muscle from women with PCOS vs controls, including DYRK1A, SYNPO2, SCP2, and NAMPT. Furthermore, women with PCOS had reduced expression of genes involved in immune system pathways. Two CpG sites showed differential DNA methylation after correction for multiple testing. However, an mRNA expression of ∼30% of the differentially expressed genes correlated with DNA methylation levels of CpG sites in or near the gene. Functional follow-up studies demonstrated that KLF10 is under transcriptional control of insulin, where insulin promotes glycogen accumulation in myotubes of human muscle cells. Testosterone downregulates the expression levels of COL1A1 and MAP2K6. Conclusion: PCOS is associated with aberrant skeletal muscle gene expression with dysregulated pathways. Furthermore, we identified specific changes in muscle DNA methylation that may affect gene expression. This study showed that women with PCOS have epigenetic and transcriptional changes in skeletal muscle that, in part, can explain the metabolic abnormalities seen in these women.

Intact regulation of muscle expression and circulating levels of myokines in response to exercise in patients with type 2 diabetes.

Regular exercise plays an important role in the prevention and treatment of type 2 diabetes (T2D). The synthesis and secretion of myokines in response to contraction may contribute to the beneficial metabolic effects of exercise. However, some exercise-induced responses may be attenuated in T2D. Here, we investigated whether the effect of acute exercise on selected myokines are impaired in T2D. Skeletal muscle biopsies and blood samples were obtained from 13 men with T2D and 14 weight-matched, glucose-tolerant men before, immediately after and 3-h after acute exercise (60 min cycling) to examine muscle expression and plasma/serum levels of selected myokines. One-hour of exercise increased muscle expression of IL6, FGF21, ANGPTL4, CHI3L1, CTGF and CYR61, of which FGF21, ANGPTL4 and CHI3L1 increased further 3-h into recovery, whereas expression of IL6, CYR61, and CTGF returned to baseline levels. There was no immediate effect of exercise on IL15 expression, but it decreased 3-h into recovery. Plasma IL-6 increased robustly, whereas circulating levels of FGF21, ANGPTL4, IL-15, and CHI3L1 increased only modestly in response to exercise. All returned toward baseline levels 3-h into recovery except for plasma ANGPTL4, which increased further. No significant differences in these responses to exercise were observed between the groups. Our results demonstrate that muscle expression and circulating levels of selected known and putative myokines were equally regulated by acute exercise in patients with T2D and weight-matched controls. This suggests that the potential beneficial metabolic effects of these myokines are not impaired in patients with T2D.

Renal function markers and insulin sensitivity after 3 years in a healthy cohort, the EGIR-RISC study.

BACKGROUND: People with chronic renal disease are insulin resistant. We hypothesized that in a healthy population, baseline renal function is associated with insulin sensitivity three years later. METHODS: We studied 405 men and 528 women from the European Group for the study of Insulin Resistance - Relationship between Insulin Sensitivity and Cardiovascular disease cohort. Renal function was characterized by the estimated glomerular filtration rate (eGFR) and by the urinary albumin-creatinine ratio (UACR). At baseline only, insulin sensitivity was quantified using a hyperinsulinaemic-euglycaemic clamp; at baseline and three years, we used surrogate measures: the Matsuda insulin sensitivity index (ISI), the HOmeostasis Model Assessment of Insulin Sensitivity (HOMA-IS). Associations between renal function and insulin sensitivity were studied cross-sectionally and longitudinally. RESULTS: In men at baseline, no associations were seen with eGFR, but there was some evidence of a positive association with UACR. In women, all insulin sensitivity indices showed the same negative trend across eGFR classes, albeit not always statistically significant; for UACR, women with values above the limit of detection, had higher clamp measured insulin sensitivity than other women. After three years, in men only, ISI and HOMA-IS showed a U-shaped relation with baseline eGFR; women with eGFR> 105 ml/min/1.73m2 had a significantly higher insulin sensitivity than the reference group (eGFR: 90-105 ml/min/1.73m2). For both men and women, year-3 insulin sensitivity was higher in those with higher baseline UACR. All associations were attenuated after adjusting on significant covariates. CONCLUSIONS: There was no evidence to support our hypothesis that markers of poorer renal function are associated with declining insulin sensitivity in our healthy population.

The relationship between bone turnover and insulin sensitivity and secretion: Cross-sectional and prospective data from the RISC cohort study.

Bone metabolism appears to influence insulin secretion and sensitivity, and insulin promotes bone formation in animals, but similar evidence in humans is limited. The objectives of this study are to explore if bone turnover markers were associated with insulin secretion and sensitivity and to determine if bone turnover markers predict changes in insulin secretion and sensitivity. The study population encompassed 576 non-diabetic adult men with normal glucose tolerance (NGT; n=503) or impaired glucose regulation (IGR; n=73). Baseline markers of bone resorption (CTX) and formation (P1NP) were determined in the fasting state and after a 2-h hyperinsulinaemic, euglycaemic clamp. An intravenous glucose tolerance test (IVGTT) and a 2-h oral glucose tolerance test (OGTT) were performed at baseline, and the OGTT was repeated after 3years. There were no differences in bone turnover marker levels between NGT and IGR. CTX and P1NP levels decreased by 8.0% (p<0.001) and 1.9% (p<0.01) between baseline and steady-state during the clamp. Fasting plasma glucose was inversely associated with CTX and P1NP both before and after adjustment for recruitment centre, age, BMI, smoking and physical activity. However, baseline bone turnover markers were neither associated with insulin sensitivity (assessed using hyperinsulinaemic euglycaemic clamp and OGTT) nor with insulin secretion capacity (based on IVGTT and OGTT) at baseline or at follow-up. Although inverse associations between fasting glucose and markers of bone turnover were identified, this study cannot support an association between insulin secretion and sensitivity in healthy, non-diabetic men.

Autonomic nervous system activation mediates the increase in whole-body glucose uptake in response to electroacupuncture.

A single bout of low-frequency electroacupuncture (EA) causing muscle contractions increases whole-body glucose uptake in insulin-resistant rats. We explored the underlying mechanism of this finding and whether it can be translated into clinical settings. Changes in glucose infusion rate (GIR) were measured by euglycemic-hyperinsulinemic clamp during and after 45 min of low-frequency EA in 21 overweight/obese women with polycystic ovary syndrome (PCOS) and 21 controls matched for age, weight, and body mass index (experiment 1) and in rats receiving autonomic receptor blockers (experiment 2). GIR was higher after EA in controls and women with PCOS. Plasma serotonin levels and homovanillic acid, markers of vagal activity, decreased in both controls and patients with PCOS. Adipose tissue expression of pro-nerve growth factor (proNGF) decreased, and the mature NGF/proNGF ratio increased after EA in PCOS, but not in controls, suggesting increased sympathetic-driven adipose tissue metabolism. Administration of α-/ß-adrenergic receptor blockers in rats blocked the increase in GIR in response to EA. Muscarinic and dopamine receptor antagonist also blocked the response but with slower onset. In conclusion, a single bout of EA increases whole-body glucose uptake by activation of the sympathetic and partly the parasympathetic nervous systems, which could have important clinical implications for the treatment of insulin resistance.-Benrick, A., Kokosar, M., Hu, M., Larsson, M., Maliqueo, M., Marcondes, R. R., Soligo, M., Protto, V., Jerlhag, E., Sazonova, A., Behre, C. J., Højlund, K., Thorén, P., Stener-Victorin, E. Autonomic nervous system activation mediates the increase in whole-body glucose uptake in response to electroacupuncture.

Intact initiation of autophagy and mitochondrial fission by acute exercise in skeletal muscle of patients with Type 2 diabetes.

Type 2 diabetes (T2D) is characterized by insulin resistance, mitochondrial dysregulation and, in some studies, exercise resistance in skeletal muscle. Regulation of autophagy and mitochondrial dynamics during exercise and recovery is important for skeletal muscle homoeostasis, and these responses may be altered in T2D. We examined the effect of acute exercise on markers of autophagy and mitochondrial fusion and fission in skeletal muscle biopsies from patients with T2D (n=13) and weight-matched controls (n=14) before, immediately after and 3 h after an acute bout of exercise. Although mRNA levels of most markers of autophagy [PIK3C, MAP1LC3B, sequestosome 1 (SQSTM1), BCL-2/adenovirus E1B 19-kDa-interacting protein 3 (BNIP3), BNIP3-like (BNIP3L)] and mitochondrial dynamics [optic atrophy 1 (OPA1), fission protein 1 (FIS1)] remained unchanged, some either increased during and after exercise (GABARAPL1), decreased in the recovery period [BECN1, autophagy-related (ATG) 7, DNM1L] or both [mitofusin (MFN) 2, mitochondrial E3 ubiquitin ligase 1 (MUL1)]. Protein levels of ATG7, p62/SQSTM1, forkhead box O3A (FOXO3A) and MFN2 (only controls) as well as dynamin-related protein 1 (DRP1) Ser616 phosphorylation increased in response to exercise and/or recovery, whereas microtubule-associated protein 1 light chain 3B (LC3B)-II content was reduced immediately after exercise. Exercise increased the activating Ser555 phosphorylation and reduced the inhibitory Ser757 phosphorylation of Unc-51-like kinase-1 (ULK1). The LC3B-II content and phosphorylation of ULK1 and DRP1 returned towards pre-exercise levels in the recovery period. Insulin sensitivity was reduced in T2D, but with no differences in the autophagic response to exercise. Our results demonstrate that initiation of autophagy and mitochondrial fission is activated by exercise in human skeletal muscle, and that these responses are intact in T2D. The exercise-induced decrease in LC3B-II could be due to increased autophagic turnover.