Adipose Tissue Macrophage-Derived Exosomal miRNAs Can Modulate In Vivo and In Vitro Insulin Sensitivity.

MiRNAs are regulatory molecules that can be packaged into exosomes and secreted from cells. Here, we show that adipose tissue macrophages (ATMs) in obese mice secrete miRNA-containing exosomes (Exos), which cause glucose intolerance and insulin resistance when administered to lean mice. Conversely, ATM Exos obtained from lean mice improve glucose tolerance and insulin sensitivity when administered to obese recipients. miR-155 is one of the miRNAs overexpressed in obese ATM Exos, and earlier studies have shown that PPARγ is a miR-155 target. Our results show that miR-155KO animals are insulin sensitive and glucose tolerant compared to controls. Furthermore, transplantation of WT bone marrow into miR-155KO mice mitigated this phenotype. Taken together, these studies show that ATMs secrete exosomes containing miRNA cargo. These miRNAs can be transferred to insulin target cell types through mechanisms of paracrine or endocrine regulation with robust effects on cellular insulin action, in vivo insulin sensitivity, and overall glucose homeostasis.

Chronic tissue inflammation and metabolic disease.

Obesity is the most common cause of insulin resistance, and the current obesity epidemic is driving a parallel rise in the incidence of T2DM. It is now widely recognized that chronic, subacute tissue inflammation is a major etiologic component of the pathogenesis of insulin resistance and metabolic dysfunction in obesity. Here, we summarize recent advances in our understanding of immunometabolism. We discuss the characteristics of chronic inflammation in the major metabolic tissues and how obesity triggers these events, including a focus on the role of adipose tissue hypoxia and macrophage-derived exosomes. Last, we also review current and potential new therapeutic strategies based on immunomodulation.

Tipepidine activates AMPK and improves adipose tissue fibrosis and glucose intolerance in high-fat diet-induced obese mice.

Tipepidine (3-[di-2-thienylmethylene]-1-methylpiperidine) (TP) is a non-narcotic antitussive used in Japan. Recently, the potential application of TP in the treatment of neuropsychiatric disorders, such as depression and attention deficit hyperactivity disorder, has been suggested; however, its functions in energy metabolism are unknown. Here, we demonstrate that TP exhibits a metabolism-improving action. The administration of TP reduced high-fat diet-induced body weight gain in mice and lipid accumulation in the liver and increased the weight of epididymal white adipose tissue (eWAT) in diet-induced obese (DIO) mice. Furthermore, TP inhibited obesity-induced fibrosis in the eWAT. We also found that TP induced AMP-activated protein kinase (AMPK) activation in the eWAT of DIO mice and 3T3-L1 cells. TP-induced AMPK activation was abrogated by the transfection of liver kinase B1 siRNA in 3T3-L1 cells. The metabolic effects of TP were almost equivalent to those of metformin, an AMPK activator that is used as a first-line antidiabetic drug. In summary, TP is a potent AMPK activator, suggesting its novel role as an antidiabetic drug owing to its antifibrotic effect on adipose tissues.

Quantitative Metabolomics and Lipoprotein Analysis of PDAC Patients Suggests Serum Marker Categories for Pancreatic Function, Pancreatectomy, Cancer Metabolism, and Systemic Disturbances.

Pancreatic ductal adenocarcinoma (PDAC) is difficult to diagnose in the early stages and lacks reliable biomarkers. The scope of this project was to establish quantitative nuclear magnetic resonance (NMR) spectroscopy to comprehensively study blood serum alterations in PDAC patients. Serum samples from 34 PDAC patients obtained before and after pancreatectomy as well as 83 age- and sex-matched control samples from healthy donors were analyzed with in vitro diagnostics research (IVDr) proton NMR spectroscopy at 600 MHz. Uni- and multivariate statistics were applied to identify significant biofluid alterations. We identified 29 significantly changed metabolites and 98 lipoproteins when comparing serum from healthy controls with those of PDAC patients. The most prominent features were assigned to (i) markers of pancreatic function (e.g., glucose and blood triglycerides), (ii) markers related to surgery (e.g., ketone bodies and blood cholesterols), (iii) PDAC-associated markers (e.g., amino acids and creatine), and (iv) markers for systemic disturbances in PDAC (e.g., gut metabolites DMG, TMAO, DMSO2, and liver lipoproteins). Quantitative serum NMR spectroscopy is suited as a diagnostic tool to investigate PDAC. Remarkably, 2-hydroxybutyrate (2-HB) as a previously suggested marker for insulin resistance was found in extraordinarily high levels only after pancreatectomy, suggesting this metabolite is the strongest marker for pancreatic loss of function.

Antidiabetic Effect of Urolithin A in Cultured L6 Myotubes and Type 2 Diabetic Model KK-Ay/Ta Mice with Glucose Intolerance.

Diabetes is caused by abnormal glucose metabolism, and muscle, the largest tissue in the human body, is largely involved. Urolithin A (UroA) is a major intestinal and microbial metabolite of ellagic acid and ellagitannins and is found in fruits such as strawberry and pomegranate. In this present study, we investigated the antidiabetic effects of UroA in L6 myotubes and in KK-Ay/Ta, a mouse model of type 2 diabetes (T2D). UroA treatment elevated the glucose uptake (GU) of L6 myotubes in the absence of insulin. This elevation in GU by UroA treatment was partially inhibited by the concurrent addition of LY294002, an inhibitor of phosphatidylinositol 3-kinase (PI3K) which activates Akt (PKB: protein kinase B) or Compound C, an inhibitor of 5'-adenosine monophosphate-activated protein kinase (AMPK). Moreover, UroA was found to activate both pathways of Akt and AMPK, and then to promote translocation of glucose transporter 4 (GLUT4) from the cytosol to the plasma membrane in L6 myotubes. Based on these in vitro findings, an intraperitoneal glucose tolerance test (IPGTT) was performed after the oral administration of UroA for 3 weeks to KK-Ay/Ta mice with glucose intolerance. UroA was demonstrated to alleviate glucose intolerance. These results suggest that UroA is a biofactor with antihyperglycemic effects in the T2D state.

Sex-dependent effects of carbohydrate source and quantity on caspase-1 activity in the mouse central nervous system.

BACKGROUND: Mounting evidence links glucose intolerance and diabetes as aspects of metabolic dysregulation that are associated with an increased risk of developing dementia. Inflammation and inflammasome activation have emerged as a potential link between these disparate pathologies. As diet is a key factor in both the development of metabolic disorders and inflammation, we hypothesize that long term changes in dietary factors can influence nervous system function by regulating inflammasome activity and that this phenotype would be sex-dependent, as sex hormones are known to regulate metabolism and immune processes. METHODS: 5-week-old male and female transgenic mice expressing a caspase-1 bioluminescent reporter underwent cranial window surgeries and were fed control (65% complex carbohydrates, 15% fat), high glycemic index (65% carbohydrates from sucrose, 15% fat), or ketogenic (1% complex carbohydrates, 79% fat) diet from 6 to 26 weeks of age. Glucose regulation was assessed with a glucose tolerance test following a 4-h morning fast. Bioluminescence in the brain was quantified using IVIS in vivo imaging. Blood cytokine levels were measured using cytokine bead array. 16S ribosomal RNA gene amplicon sequencing of mouse feces was performed to assess alterations in the gut microbiome. Behavior associated with these dietary changes was also evaluated. RESULTS: The ketogenic diet caused weight gain and glucose intolerance in both male and female mice. In male mice, the high glycemic diet led to increased caspase-1 biosensor activation over the course of the study, while in females the ketogenic diet drove an increase in biosensor activation compared to their respective controls. These changes correlated with an increase in inflammatory cytokines present in the serum of test mice and the emergence of anxiety-like behavior. The microbiome composition differed significantly between diets; however no significant link between diet, glucose tolerance, or caspase-1 signal was established. CONCLUSIONS: Our findings suggest that diet composition, specifically the source and quantity of carbohydrates, has sex-specific effects on inflammasome activation in the central nervous system and behavior. This phenotype manifested as increased anxiety in male mice, and future studies are needed to determine if this phenotype is linked to alterations in microbiome composition.

One-year postpartum weight retention and glucose intolerance in women with prediabetes after gestational diabetes.

AIMS: To determine risk factors for 1-year postpartum weight retention (PPWR) and glucose intolerance (prediabetes + diabetes) in women with a previous history of gestational diabetes (GDM) and prediabetes in early postpartum. METHODS: In this exploratory analysis of the MELINDA randomized controlled trial, we report data of 167 women with prediabetes at the 6-16 weeks (early) postpartum oral glucose tolerance test after a recent history of GDM. RESULTS: Of all participants, 45% (75) had PPWR >0 kg at 1-year postpartum. Compared to women without PPWR, women with PPWR had higher gestational weight gain [10.5 ± 6.4 vs. 6.5 ± 4.5 kg, p < 0.001], higher BMI (p < 0.01) and a worse metabolic profile (higher waist circumference, worse lipid profile and more insulin resistance) (all p < 0.05) both in early and late postpartum. Of all women with PPWR, 40.0% developed metabolic syndrome, compared to 18.9% of women without late PPWR (p = 0.003). The only independent predictor for late PPWR was weight retention in early postpartum (p < 0.001). Of all participants, 55.1% (92) had glucose intolerance (84 prediabetes, 8 diabetes) 1-year postpartum. Independent predictors for late postpartum glucose intolerance were lower gestational age at start insulin therapy in pregnancy and delivery by caesarean section (resp. p = 0.044 and 0.014). CONCLUSIONS: In women with a previous history of GDM and prediabetes in early postpartum, PPWR in early postpartum was a strong independent predictor for late PPWR, while earlier start of insulin therapy during pregnancy and delivery by caesarean section were independent predictors of glucose intolerance in late postpartum.

Tyrosine Hydroxylase Knockdown at the Hypothalamic Supramammillary Nucleus Area Induces Obesity and Glucose Intolerance.

INTRODUCTION: The supramammillary nucleus (SuMN) exerts influences on a wide range of brain functions including feeding and feeding-independent fuel metabolism. However, which specific neuronal type(s) within the SuMN manifest this influence has not been delineated. This study investigated the effect of SuMN tyrosine hydroxylase (TH) (rate-limiting enzyme in dopamine synthesis) knockdown (THx) on peripheral fuel metabolism. METHODS: SuMN-THx was accomplished using a virus-mediated shRNA to locally knockdown TH gene expression at the SuMN. The impact of SuMN-THx was examined over 35-72 days in rats least prone to developing metabolic syndrome (MS) - female Sprague-Dawley rats resistant to the obesogenic effect of high fat diet (HFDr) and fed regular chow (RC) - upon body weight/fat, feeding, glucose tolerance, and insulin sensitivity. The influence of HFD, gender, and long-term response of SuMN-THx was subsequently investigated in female HFDr rats fed HFD, male HFDr rats fed RC, and female HFD-sensitive rats fed RC over 1 year, respectively. RESULTS: SuMN-THx induced obesity and glucose intolerance, elevated plasma leptin and triglycerides, increased hepatic mRNA levels of gluconeogenic, lipogenic, and pro-inflammatory genes, reduced white adipose fatty acid oxidation rate, and altered plasma corticosterone level and hepatic circadian gene expression. Moreover, SuMN-THx increased feeding during the natural resting/fasting period and altered ghrelin feeding response suggesting ghrelin resistance. This MS-inducing effect was enhanced by HFD feeding, similarly observed in male rats and persisted over 1 year. DISCUSSION/CONCLUSION: SuMN-THx induced long-term, gender-nonspecific, multiple pathophysiological changes leading to MS suggesting SuMN dopaminergic circuits communicating with other brain metabolism and behavior control centers modulate peripheral fuel metabolism.

Influence of a diet and/or exercise intervention on long-term mortality and vascular complications in people with impaired glucose tolerance: Da Qing Diabetes Prevention Outcome study.

AIM: We aimed to investigate the long-term influence of a diet and/or exercise intervention on long-term mortality and cardiovascular disease (CVD) events. METHODS: The Da Qing Diabetes Prevention Study had 576 participants with impaired glucose tolerance (IGT) randomized to diet-only, exercise-only and diet-plus-exercise intervention group and control group. The participants underwent lifestyle interventions for 6 years. The subsequent Da Qing Diabetes Prevention Outcome Study was a prospective cohort study to follow-up the participants for up to 24 years after the end of 6-year intervention. In total, 540 participants completed the follow-up, while 36 subjects lost in follow-up. Cox proportional hazards analysis was applied to assess the influence of lifestyle interventions on targeted outcomes. RESULTS: Compared with controls, the diet-only intervention in people with IGT was significantly associated with a reduced risk of all-cause death [hazard ratio (HR) 0.77, 95% confidence interval (CI) (0.61-0.97)], CVD death [HR 0.67, 95% CI (0.46-0.97)] and CVD events [HR 0.72, 95% CI (0.54-0.96)]. The diet-plus-exercise intervention was significantly associated with a decreased risk of all-cause death [HR 0.64, 95% CI (0.48-0.84)], CVD death [HR 0.54, 95% CI (0.30-0.97)] and CVD events [HR 0.68, 95% CI (0.52-0.90)]. Unexpectedly, the exercise-only intervention was not significantly associated with the reduction of any of these outcomes, although there was a consistent trend towards reduction. CONCLUSIONS: A diet-only intervention and a diet-plus-exercise intervention in people with IGT were significantly associated with a reduced risk of all-cause death, CVD death and CVD events, while an exercise-only intervention was not. It suggests that diet-related interventions may have a potentially more reliable influence on long-term vascular complications and mortality.

Glucose intolerance induces anxiety-like behaviors independent of obesity and insulin resistance in a novel model of nutritional metabolic stress.

OBJECTIVES: Type 2 diabetes (T2D) is a metabolic disease of major public health concern. It impacts peripheral tissues and the central nervous system, leading to systemic dysmetabolism and neurocognitive impairments, including memory deficits, anxiety, and depression. The metabolic determinants of these neurocognitive impairments remain unidentified. Here, we sought to address this question by developing a proprietary (P-) high-fat diet (HFD), in which glucose intolerance precedes weight gain and insulin resistance. METHODS: The P-HFD model was nutritionally characterized, and tested in vivo in mice that underwent behavioral and metabolic testing. The diet was benchmarked against reference models. . RESULTS: P-HFD has 42% kcal from fat, high monounsaturated/polyunsaturated fatty acid ratio, and 10% (w/v) sucrose in drinking water. When administered, from the early stages of glucose intolerance alone, animals exhibit anxiety-like behavior, without depression nor recognition memory deficits. Long-term P-HFD feeding leads to weight gain, brain glucose hypometabolism as well as impaired recognition memory. Using an established genetic model of T2D (db/db) and of diet-induced obesity (60% kcal from fat) we show that additional insulin resistance and obesity are associated with depressive-like behaviors and recognition memory deficits. DISCUSSION: Our findings demonstrate that glucose intolerance alone can elicit anxiety-like behavior. Through this study, we also provide a novel nutritional model (P-HFD) to characterize the discrete effects of glucose intolerance on cognition, behavior, and the physiology of metabolic disease.

Glucose intolerance in acromegaly is driven by low insulin secretion; results from an intravenous glucose tolerance test.

PURPOSE: Insulin sensitivity (Si) and its role in glucose intolerance of acromegaly has been extensively evaluated. However, data on insulin secretion is limited. We aimed to assess stimulated insulin secretion using an intravenous glucose tolerance test (IVGTT) in active acromegaly. METHODS: We performed an IVGTT in 25 patients with active acromegaly (13 normal glucose tolerance [NGT], 6 impaired glucose tolerance [IGT] and 6 diabetes mellitus [DM]) and 23 controls (8 lean NGT, 8 obese NGT and 7 obese IGT). Serum glucose and insulin were measured at 20 time points along the test to calculate Si and acute insulin response (AIRg). Medical treatment for acromegaly or diabetes was not allowed. RESULTS: In acromegaly, patients with NGT had significantly (p for trend < 0.001) higher AIRg (3383 ± 1082 pmol*min/L) than IGT (1215 ± 1069) and DM (506 ± 600). AIRg was higher in NGT (4764 ± 1180 pmol*min/L) and IGT (3183 ± 3261) controls with obesity than NGT (p = 0.01) or IGT (p = 0.17) acromegaly. Si was not significantly lower in IGT (0.68 [0.37, 0.88] 106*L/pmol*min) and DM (0.60 [0.42, 0.84]) than in NGT (0.81 [0.58, 1.55]) patients with acromegaly. NGT (0.33 [0.30, 0.47] 106*L/pmol*min) and IGT (0.37 [0.21, 0.66]) controls with obesity had lower Si than NGT (p = 0.001) and IGT (p = 0.43) acromegaly. CONCLUSION: We demonstrated that low insulin secretion is the main driver behind glucose intolerance in acromegaly. Compared to NGT and IGT controls with obesity, patients with NGT or IGT acromegaly had higher Si. Together, these findings suggest that impaired insulin secretion might be a specific mechanism for glucose intolerance in acromegaly.

Gestational glucose intolerance among pregnant women at the Cape Coast Teaching Hospital.

BACKGROUND: Malaria in pregnancy can have adverse outcomes if untreated. Both malaria and pregnancy are associated with insulin resistance and diabetes. Although malaria is treated prophylactically with gestational diabetes mellitus (GDM) screened for in pregnancy as part a routine antenatal care, their impacts have not been examined in terms of other forms of dysglycaemia. This cross-sectional study examined insulin resistance and its relationship with dysglycaemia and malaria among pregnant women in the Cape Coast Teaching Hospital (CCTH). METHODS: Using a structured questionnaire, demographic and clinical information were obtained from 252 pregnant women aged 18-42 years. Weight and height were measured for computation of body mass index (BMI). Measurement of insulin, lipid profile and glucose were taken under fasting conditions followed by oral glucose tolerant test. Insulin resistance and beta-cell function were assessed by the homeostatic model as malaria was diagnosed by microscopy. RESULTS: The respective prevalence of GDM, gestational glucose intolerance (GGI) and insulin resistance were 0.8% (2/252), 19.44% (49/252) and 56.75% (143/252). No malaria parasite or dyslipidaemia was detected in any of the participants. Apart from BMI that increased across trimesters, no other measured parameter differed among the participants. Junior High School (JHS) education compared with no formal education increased the odds (AOR: 2.53; CI: 1.12-5.71; P = 0.03) but 2nd trimester of pregnancy compared to the 1st decreased the odds (AOR: 0.32; CI: 0.12-0.81; P = 0.02) of having insulin resistance in the entire sample. In a sub-group analysis across trimesters, pregnant women with JHS education in their 3rd trimester had increased odds (AOR: 4.41; CI: 1.25-15.62; P = 0.02) of having insulin resistance. CONCLUSION: Prevalence of GDM and GGI were 0.8% and 19.44% respectively. The odds of insulin resistance increased in pregnant women with JHS education in the 3rd trimester. Appropriate measures are needed to assuage the diabetogenic risk posed by GGI in our setting.

BCG Vaccination Suppresses Glucose Intolerance Progression in High-Fat-Diet-Fed C57BL/6 Mice.

Background and Objectives: Mycobacterium bovis Bacillus Calmette-Guérin (BCG) vaccine administration has been suggested to prevent glucose metabolism abnormalities and fatty liver in genetically obese ob/ob mice; however, it is not clear whether the beneficial effects of BCG are also observed in the progression of glucose intolerance induced by a high-fat diet (HFD). Therefore, the effects of BCG vaccination on changes in glucose tolerance and insulin response were investigated in HFD-fed C57BL/6 mice. Materials and Methods: We used the BCG Tokyo 172 strain to determine effects on abnormalities in glucose metabolism. For vaccination, five-week-old male mice were injected intraperitoneally with BCG and maintained on a HFD for three weeks. The mice were regularly subjected to intraperitoneal glucose tolerance and insulin tolerance tests (IGTTs and ITTs). These tests were also performed in mice transplanted with bone marrow cells from BCG-vaccinated donor mice. Results: Significant effects of BCG vaccination on blood glucose levels in the IGTTs and ITTs were observed from week 12 of the experiment. BCG vaccination significantly improved changes in fasting glucose and insulin levels, insulin resistance indexes, and glucagon-to-insulin ratios in conjunction with the HFD at the end of the experiment. Significant inhibitory effects in the IGTTs and ITTs on glucose intolerance were also observed with transplantation with bone marrow cells derived from BCG-vaccinated donor mice. Conclusions: BCG vaccination significantly delayed glucose intolerance progression, suggesting a beneficial effect of BCG on the pathogenesis of type 2 diabetes. It has also been suggested that the effects of BCG vaccination may be at least partially due to an immune memory (trained immunity) for hematopoietic stem and progenitor cells of the bone marrow.

Skeletal muscle and intermuscular adipose tissue gene expression profiling identifies new biomarkers with prognostic significance for insulin resistance progression and intervention response.

AIMS/HYPOTHESIS: Although insulin resistance often leads to type 2 diabetes mellitus, its early stages are often unrecognised, thus reducing the probability of successful prevention and intervention. Moreover, treatment efficacy is affected by the genetics of the individual. We used gene expression profiles from a cross-sectional study to identify potential candidate genes for the prediction of diabetes risk and intervention response. METHODS: Using a multivariate regression model, we linked gene expression profiles of human skeletal muscle and intermuscular adipose tissue (IMAT) to fasting glucose levels and glucose infusion rate. Based on the expression patterns of the top predictive genes, we characterised and compared individual gene expression with clinical classifications using k-nearest neighbour clustering. The predictive potential of the candidate genes identified was validated using muscle gene expression data from a longitudinal intervention study. RESULTS: We found that genes with a strong association with clinical measures clustered into three distinct expression patterns. Their predictive values for insulin resistance varied substantially between skeletal muscle and IMAT. Moreover, we discovered that individual gene expression-based classifications may differ from classifications based predominantly on clinical variables, indicating that participant stratification may be imprecise if only clinical variables are used for classification. Of the 15 top candidate genes, ST3GAL2, AASS, ARF1 and the transcription factor SIN3A are novel candidates for predicting a refined diabetes risk and intervention response. CONCLUSION/INTERPRETATION: Our results confirm that disease progression and successful intervention depend on individual gene expression states. We anticipate that our findings may lead to a better understanding and prediction of individual diabetes risk and may help to develop individualised intervention strategies.

Endocrine disorders in obstructive sleep apnoea syndrome: A bidirectional relationship.

Obstructive sleep apnoea (OSA) is a common disorder characterized by recurrent episodes of apnoea or hypopnea due to total or partial pharyngeal collapse and temporary upper airway obstruction during sleep. The prevalence of OSA is increasing and currently affects about 30% of men and 13% of women in Europe. Intermittent hypoxia, oxidative stress, systemic inflammation, and sleep fragmentation resulting from OSA can provoke subsequent cardiometabolic disorders. The relationships between endocrine disorders and OSA are complex and bidirectional. Indeed, several endocrine disorders are risk factors for OSA. Compared with the general population, the prevalence of OSA is increased in patients with obesity, hypothyroidism, acromegaly, Cushing syndrome, and type 1 and 2 diabetes. In some cases, treatment of the underlying endocrine disorder can improve, and occasionally cure, OSA. On the other hand, OSA can also induce endocrine disorders, particularly glucose metabolism abnormalities. Whether continuous positive airway pressure (CPAP) treatment for OSA can improve these endocrine disturbances remains unclear due to the presence of several confounding factors. In this review, we discuss the current state-of-the-art based on the review of the current medical literature for key articles focusing on the bidirectional relationship between endocrine disorders and OSA and the effects of treatment. Screening of OSA in endocrine patients is also discussed, as it remains a subject of debate.

NPFFR2-deficient mice fed a high-fat diet develop strong intolerance to glucose.

A previous study on neuropeptide FF receptor 2 (NPFFR2)-deficient mice has demonstrated that NPFFR2 is involved in the control of energy balance and thermogenesis. Here, we report on the metabolic impact of NPFFR2 deficiency in male and female mice that were fed either a standard diet (STD) or a high-fat diet (HFD) and each experimental group consisted of ten individuals. Both male and female NPFFR2 knockout (KO) mice exhibited severe glucose intolerance that was exacerbated by a HFD diet. In addition, reduced insulin pathway signaling proteins in NPFFR2 KO mice fed a HFD resulted in the development of hypothalamic insulin resistance. HFD feeding did not cause liver steatosis in NPFFR2 KO mice of either sex, but NPFFR2 KO male mice fed a HFD had lower body weights, white adipose tissues, and liver and lower plasma leptin levels compared with their wild-type (WT) controls. Lower liver weight in NPFFR2 KO male mice compensated for HFD-induced metabolic stress by increased liver PPARα and plasma FGF21 hepatokine, which supported fatty acid ß-oxidation in the liver and white adipose tissue. Conversely, NPFFR2 deletion in female mice attenuated the expression of Adra3ß and Pparγ, which inhibited lipolysis in adipose tissue.

Normalization of maternal adiponectin in obese pregnant mice prevents programming of impaired glucose metabolism in adult offspring.

Infants born to obese mothers have a greater risk for childhood obesity and insulin resistance. However, the underlying biological mechanism remains elusive, which constitutes a significant roadblock for developing specific prevention strategies. Maternal adiponectin levels are lower in obese pregnant women, which is linked with increased placental nutrient transport and fetal overgrowth. We have previously reported that adiponectin supplementation to obese dams during the last four days of pregnancy prevented the development of obesity, glucose intolerance, muscle insulin resistance, and fatty liver in three months old offspring. In the present study, we tested the hypothesis that 6-9-month-old offspring of obese dams show glucose intolerance associated with muscle insulin resistance and mitochondrial dysfunction and that normalization of maternal adiponectin in obese pregnant mice prevents the development of this phenotype in the offspring. Male and female offspring of obese mice exhibited in vivo glucose intolerance and insulin resistance at 6 and 9 months of age. In gastrocnemius muscles ex vivo, male and female offspring of obese dams showed reduced phosphorylation of insulin receptor substrate 1Tyr-608 , AktThr-308 , and decreased Glut4 plasma membrane translocation upon insulin stimulation. These metabolic abnormalities in offspring born to obese mice were largely prevented by normalization of maternal adiponectin levels in late pregnancy. We provide evidence that low circulating maternal adiponectin is a critical mechanistic link between maternal obesity and the development of metabolic disease in offspring. Strategies aimed at improving maternal adiponectin levels may prevent long-term metabolic dysfunction in offspring of obese mothers.

The utility of plasma glycated CD59 in predicting postpartum glucose intolerance: A prospective study of women diagnosed with GDM during a period of universal GDM screening.

AIMS: Gestational diabetes (GDM) is associated with the development of postpartum (PP) glucose intolerance. Plasma glycated CD59 (pGCD59) is an emerging biomarker for the detection of hyperglycaemia. The aim of this study was to assess the ability of PP pGCD59 to predict the development of PP GI as defined by the 2 h 75 g OGTT using the ADA criteria, in a cohort of women diagnosed with prior GDM in the index pregnancy using the 2 h 75 g OGTT at 24-28 weeks of gestation according to the World Health Organization (WHO) 2013 criteria. METHODS: Of the 2017 pregnant women recruited prospectively 140 women with gestational diabetes had samples for pGCD59 taken PP at the time of the OGTT. The ability of pGCD59 to predict the results of the PP OGTT was assessed using nonparametric receiver operating characteristic (ROC) curves. RESULTS: Women with PP glucose intolerance had significantly higher PP pGCD59 levels compared to women with normal glucose tolerance PP (3.8 vs. 2.7 SPU). PP pGCD59 identified women who developed glucose intolerance PP with an AUC of 0.80 (95% CI: 0.70-0.91). A PP pGCD59 cut-off value of 1.9 SPU generated a sensitivity of 100% (95% CI: 83.9-100), specificity of 16.9% (95% CI: 9.8-26.3), positive predictive value of 22.1% (95% CI: 21.0-22.6), and negative predictive value of 100% (95% CI: 87.4-100). PP fasting plasma glucose generated an AUC of 0.96 (95% CI: 0.89-0.99) for the identification of PP glucose intolerance. CONCLUSION: Our study found that PP pGCD9 may be a promising biomarker to identify women not requiring PP glucose intolerance screening using the traditional OGTT. While the diagnostic accuracy of pGCD59 is good, fasting plasma glucose remains a better test for the identification of PP glucose intolerance.

Models Predicting Postpartum Glucose Intolerance Among Women with a History of Gestational Diabetes Mellitus: a Systematic Review.

PURPOSE OF REVIEW: Despite the crucial role that prediction models play in guiding early risk stratification and timely intervention to prevent type 2 diabetes after gestational diabetes mellitus (GDM), their use is not widespread in clinical practice. The purpose of this review is to examine the methodological characteristics and quality of existing prognostic models predicting postpartum glucose intolerance following GDM. RECENT FINDINGS: A systematic review was conducted on relevant risk prediction models, resulting in 15 eligible publications from research groups in various countries. Our review found that traditional statistical models were more common than machine learning models, and only two were assessed to have a low risk of bias. Seven were internally validated, but none were externally validated. Model discrimination and calibration were done in 13 and four studies, respectively. Various predictors were identified, including body mass index, fasting glucose concentration during pregnancy, maternal age, family history of diabetes, biochemical variables, oral glucose tolerance test, use of insulin in pregnancy, postnatal fasting glucose level, genetic risk factors, hemoglobin A1c, and weight. The existing prognostic models for glucose intolerance following GDM have various methodological shortcomings, with only a few models being assessed to have low risk of bias and validated internally. Future research should prioritize the development of robust, high-quality risk prediction models that follow appropriate guidelines, in order to advance this area and improve early risk stratification and intervention for glucose intolerance and type 2 diabetes among women who have had GDM.

Prolonged fasting outperforms short-term fasting in terms of glucose tolerance and insulin release: a randomised controlled trial.

Fasting is related to glucose intolerance and insulin resistance, but it is unknown whether the duration of fasting influences these factors. We explored whether prolonged fasting increases norepinephrine and ketone concentrations and decreases core temperature to a greater extent than short-term fasting; if so, this should lead to improved glucose tolerance. Forty-three healthy young adult males were randomly assigned to undergo a 2-d fast, 6-d fast or the usual diet. Changes in rectal temperature (TR), ketone and catecholamine concentrations, glucose tolerance and insulin release in response to an oral glucose tolerance test were assessed. Both fasting trials increased ketone concentration, and the effect was larger after the 6-d fast (P < 0·05). TR and epinephrine concentration increased only after the 2-d fast (P < 0·05). Both fasting trials increased the glucose area under the curve (AUC) (P < 0·05), but the AUC remained higher than the baseline value after participants returned to their usual diet in the 2-d fast group (P < 0·05). Neither fasting had an immediate effect on the insulin AUC, although it increased after return to their usual diet in the 6-d fast group (P < 0·05). These data suggest that the 2-d fast elicited residual impaired glucose tolerance, which may be linked to greater perceived stress during short-term fasting, as shown by the epinephrine response and change in core temperature. By contrast, prolonged fasting seemed to evoke an adaptive residual mechanism that is related to improved insulin release and maintained glucose tolerance.