Showing papers on "Insulin published in 2017"

Clinical Review of Antidiabetic Drugs: Implications for Type 2 Diabetes Mellitus Management

Abstract: Type 2 diabetes mellitus (T2DM) is a global pandemic, as evident from the global cartographic picture of diabetes by the International Diabetes Federation (http://www.diabetesatlas.org/). Diabetes mellitus is a chronic, progressive, incompletely understood metabolic condition chiefly characterized by hyperglycemia. Impaired insulin secretion, resistance to tissue actions of insulin, or a combination of both are thought to be the commonest reasons contributing to the pathophysiology of T2DM, a spectrum of disease originally arising from tissue insulin resistance and gradually progressing to a state characterized by complete loss of secretory activity of the beta cells of the pancreas. T2DM is a major contributor to the very large rise in the rate of non-communicable diseases affecting developed as well as developing nations. In this mini review, we endeavor to outline the current management principles, including the spectrum of medications that are currently used for pharmacologic management, for lowering the elevated blood glucose in T2DM.

Insulin action and resistance in obesity and type 2 diabetes

Abstract: Nutritional excess is a major forerunner of type 2 diabetes. It enhances the secretion of insulin, but attenuates insulin's metabolic actions in the liver, skeletal muscle and adipose tissue. However, conflicting evidence indicates a lack of knowledge of the timing of these events during the development of obesity and diabetes, pointing to a key gap in our understanding of metabolic disease. This Perspective reviews alternate viewpoints and recent results on the temporal and mechanistic connections between hyperinsulinemia, obesity and insulin resistance. Although much attention has addressed early steps in the insulin signaling cascade, insulin resistance in obesity seems to be largely elicited downstream of these steps. New findings also connect insulin resistance to extensive metabolic cross-talk between the liver, adipose tissue, pancreas and skeletal muscle. These and other advances over the past 5 years offer exciting opportunities and daunting challenges for the development of new therapeutic strategies for the treatment of type 2 diabetes.

Type 1 Diabetes Mellitus

Abstract: Type 1 diabetes mellitus (T1DM), also known as autoimmune diabetes, is a chronic disease characterized by insulin deficiency due to pancreatic β-cell loss and leads to hyperglycaemia. Although the age of symptomatic onset is usually during childhood or adolescence, symptoms can sometimes develop much later. Although the aetiology of T1DM is not completely understood, the pathogenesis of the disease is thought to involve T cell-mediated destruction of β-cells. Islet-targeting autoantibodies that target insulin, 65 kDa glutamic acid decarboxylase, insulinoma-associated protein 2 and zinc transporter 8 - all of which are proteins associated with secretory granules in β-cells - are biomarkers of T1DM-associated autoimmunity that are found months to years before symptom onset, and can be used to identify and study individuals who are at risk of developing T1DM. The type of autoantibody that appears first depends on the environmental trigger and on genetic factors. The pathogenesis of T1DM can be divided into three stages depending on the absence or presence of hyperglycaemia and hyperglycaemia-associated symptoms (such as polyuria and thirst). A cure is not available, and patients depend on lifelong insulin injections; novel approaches to insulin treatment, such as insulin pumps, continuous glucose monitoring and hybrid closed-loop systems, are in development. Although intensive glycaemic control has reduced the incidence of microvascular and macrovascular complications, the majority of patients with T1DM are still developing these complications. Major research efforts are needed to achieve early diagnosis, prevent β-cell loss and develop better treatment options to improve the quality of life and prognosis of those affected.

Regulation of hepatic glucose metabolism in health and disease

Abstract: The liver is crucial for the maintenance of normal glucose homeostasis - it produces glucose during fasting and stores glucose postprandially. However, these hepatic processes are dysregulated in type 1 and type 2 diabetes mellitus, and this imbalance contributes to hyperglycaemia in the fasted and postprandial states. Net hepatic glucose production is the summation of glucose fluxes from gluconeogenesis, glycogenolysis, glycogen synthesis, glycolysis and other pathways. In this Review, we discuss the in vivo regulation of these hepatic glucose fluxes. In particular, we highlight the importance of indirect (extrahepatic) control of hepatic gluconeogenesis and direct (hepatic) control of hepatic glycogen metabolism. We also propose a mechanism for the progression of subclinical hepatic insulin resistance to overt fasting hyperglycaemia in type 2 diabetes mellitus. Insights into the control of hepatic gluconeogenesis by metformin and insulin and into the role of lipid-induced hepatic insulin resistance in modifying gluconeogenic and net hepatic glycogen synthetic flux are also discussed. Finally, we consider the therapeutic potential of strategies that target hepatosteatosis, hyperglucagonaemia and adipose lipolysis.

Continuous Glucose Monitoring vs Conventional Therapy for Glycemic Control in Adults With Type 1 Diabetes Treated With Multiple Daily Insulin Injections: The GOLD Randomized Clinical Trial.

Abstract: IMPORTANCE The majority of individuals with type 1 diabetes do not meet recommended glycemic targets. OBJECTIVE To evaluate the effects of continuous glucose monitoring in adults with type 1 diabetes treated with multiple daily insulin injections. DESIGN, SETTING, AND PARTICIPANTS Open-label crossover randomized clinical trial conducted in 15 diabetes outpatient clinics in Sweden between February 24, 2014, and June 1, 2016 that included 161 individuals with type 1 diabetes and hemoglobin A1c (HbA1c) of at least 7.5%(58 mmol/mol) treated with multiple daily insulin injections. INTERVENTIONS Participants were randomized to receive treatment using a continuous glucose monitoring system or conventional treatment for 26 weeks, separated by a washout period of 17 weeks. MAIN OUTCOMES AND MEASURES Difference in HbA1c between weeks 26 and 69 for the 2 treatments. Adverse events including severe hypoglycemia were also studied. RESULTS Among 161 randomized participants, mean age was 43.7 years, 45.3%were women, and mean HbA1c was 8.6%(70 mmol/mol). A total of 142 participants had follow-up data in both treatment periods. Mean HbA1c was 7.92%(63 mmol/mol) during continuous glucose monitoring use and 8.35%(68 mmol/mol) during conventional treatment (mean difference, -0.43%[95%CI, -0.57%to -0.29%] or -4.7 [-6.3 to -3.1 mmol/mol]; P < .001). Of 19 secondary end points comprising psychosocial and various glycemic measures, 6met the hierarchical testing criteria of statistical significance, favoring continuous glucose monitoring compared with conventional treatment. Five patients in the conventional treatment group and 1 patient in the continuous glucose monitoring group had severe hypoglycemia. During washout when patients used conventional therapy, 7 patients had severe hypoglycemia. CONCLUSIONS AND RELEVANCE Among patients with inadequately controlled type 1 diabetes treated with multiple daily insulin injections, the use of continuous glucose monitoring compared with conventional treatment for 26 weeks resulted in lower HbA1c. Furthe. (Less)

The Role of Oxidative Stress and Hypoxia in Pancreatic Beta-Cell Dysfunction in Diabetes Mellitus.

Abstract: Significance: Metabolic syndrome is a frequent precursor of type 2 diabetes mellitus (T2D), a disease that currently affects ∼8% of the adult population worldwide. Pancreatic beta-cell dysfunction and loss are central to the disease process, although understanding of the underlying molecular mechanisms is still fragmentary. Recent Advances: Oversupply of nutrients, including glucose and fatty acids, and the subsequent overstimulation of beta cells, are believed to be an important contributor to insulin secretory failure in T2D. Hypoxia has also recently been implicated in beta-cell damage. Accumulating evidence points to a role for oxidative stress in both processes. Although the production of reactive oxygen species (ROS) results from enhanced mitochondrial respiration during stimulation with glucose and other fuels, the expression of antioxidant defense genes is unusually low (or disallowed) in beta cells. Critical Issues: Not all subjects with metabolic syndrome and hyperglycemia go on to deve...

Impaired Glucose Homeostasis in First-Episode Schizophrenia: A Systematic Review and Meta-analysis.

Abstract: Importance Schizophrenia is associated with an increased risk of type 2 diabetes. However, it is not clear whether schizophrenia confers an inherent risk for glucose dysregulation in the absence of the effects of chronic illness and long-term treatment. Objective To conduct a meta-analysis examining whether individuals with first-episode schizophrenia already exhibit alterations in glucose homeostasis compared with controls. Data Sources The EMBASE, MEDLINE, and PsycINFO databases were systematically searched for studies examining measures of glucose homeostasis in antipsychotic-naive individuals with first-episode schizophrenia compared with individuals serving as controls. Study Selection Case-control studies reporting on fasting plasma glucose levels, plasma glucose levels after an oral glucose tolerance test, fasting plasma insulin levels, insulin resistance, and hemoglobin A 1c (HbA 1c ) levels in first-episode antipsychotic-naive individuals with first-episode schizophrenia compared with healthy individuals serving as controls. Two independent investigators selected the studies. Data Extraction Two independent investigators extracted study-level data for a random-effects meta-analysis. Standardized mean differences in fasting plasma glucose levels, plasma glucose levels after an oral glucose tolerance test, fasting plasma insulin levels, insulin resistance, and HbA 1c levels were calculated. Sensitivity analyses examining the effect of body mass index, diet and exercise, race/ethnicity, and minimal (≤2 weeks) antipsychotic exposure were performed. Data Synthesis Of 3660 citations retrieved, 16 case-control studies comprising 15 samples met inclusion criteria. The overall sample included 731 patients and 614 controls. Fasting plasma glucose levels (Hedges g = 0.20; 95% CI, 0.02 to 0.38; P = .03), plasma glucose levels after an oral glucose tolerance test (Hedges g = 0.61; 95% CI, 0.16 to 1.05; P = .007), fasting plasma insulin levels (Hedges g = 0.41; 95% CI, 0.09 to 0.72; P = .01), and insulin resistance (homeostatic model assessment of insulin resistance) (Hedges g = 0.35; 95% CI, 0.14 to 0.55; P = .001) were all significantly elevated in patients compared with controls. However, HbA 1c levels (Hedges g = −0.08; CI, −0.34 to 0.18; P = .55) were not altered in patients compared with controls. Conclusions and Relevance These findings show that glucose homeostasis is altered from illness onset in schizophrenia, indicating that patients are at increased risk of diabetes as a result. This finding has implications for the monitoring and treatment choice for patients with schizophrenia.

Gestational diabetes and adverse perinatal outcomes from 716,152 births in France in 2012

Abstract: Aims/hypothesis The aim of this study was to assess the risk of adverse perinatal outcomes in gestational diabetes mellitus (GDM) in a large national cohort.

Association of Insulin Pump Therapy vs Insulin Injection Therapy With Severe Hypoglycemia, Ketoacidosis, and Glycemic Control Among Children, Adolescents, and Young Adults With Type 1 Diabetes.

Abstract: Importance Insulin pump therapy may improve metabolic control in young patients with type 1 diabetes, but the association with short-term diabetes complications is unclear. Objective To determine whether rates of severe hypoglycemia and diabetic ketoacidosis are lower with insulin pump therapy compared with insulin injection therapy in children, adolescents, and young adults with type 1 diabetes. Design, Setting, and Participants Population-based cohort study conducted between January 2011 and December 2015 in 446 diabetes centers participating in the Diabetes Prospective Follow-up Initiative in Germany, Austria, and Luxembourg. Patients with type 1 diabetes younger than 20 years and diabetes duration of more than 1 year were identified. Propensity score matching and inverse probability of treatment weighting analyses with age, sex, diabetes duration, migration background (defined as place of birth outside of Germany or Austria), body mass index, and glycated hemoglobin as covariates were used to account for relevant confounders. Exposures Type 1 diabetes treated with insulin pump therapy or with multiple (≥4) daily insulin injections. Main Outcomes and Measures Primary outcomes were rates of severe hypoglycemia and diabetic ketoacidosis during the most recent treatment year. Secondary outcomes included glycated hemoglobin levels, insulin dose, and body mass index. Results Of 30 579 patients (mean age, 14.1 years [SD, 4.0]; 53% male), 14 119 used pump therapy (median duration, 3.7 years) and 16 460 used insulin injections (median duration, 3.6 years). Patients using pump therapy (n = 9814) were matched with 9814 patients using injection therapy. Pump therapy, compared with injection therapy, was associated with lower rates of severe hypoglycemia (9.55 vs 13.97 per 100 patient-years; difference, −4.42 [95% CI, −6.15 to −2.69];P Conclusions and Relevance Among young patients with type 1 diabetes, insulin pump therapy, compared with insulin injection therapy, was associated with lower risks of severe hypoglycemia and diabetic ketoacidosis and with better glycemic control during the most recent year of therapy. These findings provide evidence for improved clinical outcomes associated with insulin pump therapy compared with injection therapy in children, adolescents, and young adults with type 1 diabetes.

Effects of Sotagliflozin Added to Insulin in Patients with Type 1 Diabetes

Abstract: BackgroundIn most patients with type 1 diabetes, adequate glycemic control is not achieved with insulin therapy alone. We evaluated the safety and efficacy of sotagliflozin, an oral inhibitor of sodium–glucose cotransporters 1 and 2, in combination with insulin treatment in patients with type 1 diabetes. MethodsIn this phase 3, double-blind trial, which was conducted at 133 centers worldwide, we randomly assigned 1402 patients with type 1 diabetes who were receiving treatment with any insulin therapy (pump or injections) to receive sotagliflozin (400 mg per day) or placebo for 24 weeks. The primary end point was a glycated hemoglobin level lower than 7.0% at week 24, with no episodes of severe hypoglycemia or diabetic ketoacidosis after randomization. Secondary end points included the change from baseline in glycated hemoglobin level, weight, systolic blood pressure, and mean daily bolus dose of insulin. ResultsA significantly larger proportion of patients in the sotagliflozin group than in the placebo gr...

MicroRNAs in metabolism

Abstract: MicroRNAs (miRNAs) have within the past decade emerged as key regulators of metabolic homoeostasis. Major tissues in intermediary metabolism important during development of the metabolic syndrome, such as β-cells, liver, skeletal and heart muscle as well as adipose tissue, have all been shown to be affected by miRNAs. In the pancreatic β-cell, a number of miRNAs are important in maintaining the balance between differentiation and proliferation (miR-200 and miR-29 families) and insulin exocytosis in the differentiated state is controlled by miR-7, miR-375 and miR-335. MiR-33a and MiR-33b play crucial roles in cholesterol and lipid metabolism, whereas miR-103 and miR-107 regulates hepatic insulin sensitivity. In muscle tissue, a defined number of miRNAs (miR-1, miR-133, miR-206) control myofibre type switch and induce myogenic differentiation programmes. Similarly, in adipose tissue, a defined number of miRNAs control white to brown adipocyte conversion or differentiation (miR-365, miR-133, miR-455). The discovery of circulating miRNAs in exosomes emphasizes their importance as both endocrine signalling molecules and potentially disease markers. Their dysregulation in metabolic diseases, such as obesity, type 2 diabetes and atherosclerosis stresses their potential as therapeutic targets. This review emphasizes current ideas and controversies within miRNA research in metabolism.

Postprandial macrophage-derived IL-1β stimulates insulin, and both synergistically promote glucose disposal and inflammation

Abstract: The deleterious effect of chronic activation of the IL-1β system on type 2 diabetes and other metabolic diseases is well documented. However, a possible physiological role for IL-1β in glucose metabolism has remained unexplored. Here we found that feeding induced a physiological increase in the number of peritoneal macrophages that secreted IL-1β, in a glucose-dependent manner. Subsequently, IL-1β contributed to the postprandial stimulation of insulin secretion. Accordingly, lack of endogenous IL-1β signaling in mice during refeeding and obesity diminished the concentration of insulin in plasma. IL-1β and insulin increased the uptake of glucose into macrophages, and insulin reinforced a pro-inflammatory pattern via the insulin receptor, glucose metabolism, production of reactive oxygen species, and secretion of IL-1β mediated by the NLRP3 inflammasome. Postprandial inflammation might be limited by normalization of glycemia, since it was prevented by inhibition of the sodium-glucose cotransporter SGLT2. Our findings identify a physiological role for IL-1β and insulin in the regulation of both metabolism and immunity.

A Practical Review of C-Peptide Testing in Diabetes.

Abstract: C-peptide is a widely used measure of pancreatic beta cell function. It is produced in equimolar amounts to endogenous insulin but is excreted at a more constant rate over a longer time. Methods of estimation include urinary and unstimulated and stimulated serum sampling. Modern assays detect levels of c-peptide which can be used to guide diabetes diagnosis and management. We explore the evidence behind the various tests available. We recommend the glucagon stimulation c-peptide testing owing to its balance of sensitivity and practicality. C-peptide levels are associated with diabetes type and duration of disease. Specifically a c-peptide level of less than 0.2 nmol/l is associated with a diagnosis of type 1 diabetes mellitus (T1DM). C-peptide level may correlate with microvascular and macrovascular complications and future use of insulin therapy, as well as likely response to other individual therapies. We explore the potential uses of c-peptide measurement in clinical practice.

Unraveling the Regulation of Hepatic Metabolism by Insulin.

Abstract: During insulin-resistant states such as type 2 diabetes mellitus (T2DM), insulin fails to suppress hepatic glucose production but promotes lipid synthesis leading to hyperglycemia and hypertriglyceridemia. Defining the downstream signaling pathways underlying the control of hepatic metabolism by insulin is necessary for understanding both normal physiology and the pathogenesis of metabolic disease. We summarize recent literature highlighting the importance of both hepatic and extrahepatic mechanisms in insulin regulation of liver glucose and lipid metabolism. We posit that a failure of insulin to inappropriately regulate liver metabolism during T2DM is not exclusively from an inherent defect in canonical liver insulin signaling but is instead due to a combination of hyperinsulinemia, altered substrate supply, and the input of several extrahepatic signals.

Toward Defining the Threshold Between Low and High Glucose Variability in Diabetes

Abstract: OBJECTIVE To define the threshold for excess glucose variability (GV), one of the main features of dysglycemia in diabetes. RESEARCH DESIGN AND METHODS A total of 376 persons with diabetes investigated at the University Hospital of Montpellier (Montpellier, France) underwent continuous glucose monitoring. Participants with type 2 diabetes were divided into several groups—groups 1, 2a, 2b, and 3 ( n = 82, 28, 65, and 79, respectively)—according to treatment: 1 ) diet and/or insulin sensitizers alone; 2 ) oral therapy including an insulinotropic agent, dipeptidyl peptidase 4 inhibitors (group 2a) or sulfonylureas (group 2b); or 3 ) insulin. Group 4 included 122 persons with type 1 diabetes. Percentage coefficient of variation for glucose (%CV = [(SD of glucose)/(mean glucose)] × 100) and frequencies of hypoglycemia (interstitial glucose RESULTS Percentages of CV (median [interquartile range]; %) increased significantly ( P P P 36% were compared with those with %CV ≤36%. CONCLUSIONS A %CV of 36% appears to be a suitable threshold to distinguish between stable and unstable glycemia in diabetes because beyond this limit, the frequency of hypoglycemia is significantly increased, especially in insulin-treated subjects.

H2O2-Responsive Vesicles Integrated with Transcutaneous Patches for Glucose-Mediated Insulin Delivery

Abstract: A self-regulated “smart” insulin administration system would be highly desirable for diabetes management. Here, a glucose-responsive insulin delivery device, which integrates H2O2-responsive polymeric vesicles (PVs) with a transcutaneous microneedle-array patch was prepared to achieve a fast response, excellent biocompatibility, and painless administration. The PVs are self-assembled from block copolymer incorporated with polyethylene glycol (PEG) and phenylboronic ester (PBE)-conjugated polyserine (designated mPEG-b-P(Ser-PBE)) and loaded with glucose oxidase (GOx) and insulin. The polymeric vesicles function as both moieties of the glucose sensing element (GOx) and the insulin release actuator to provide basal insulin release as well as promote insulin release in response to hyperglycemic states. In the current study, insulin release responds quickly to elevated glucose and its kinetics can be modulated by adjusting the concentration of GOx loaded into the microneedles. In vivo testing indicates that a ...

Growth differentiation factor 15 is a myomitokine governing systemic energy homeostasis

Abstract: Reduced mitochondrial electron transport chain activity promotes longevity and improves energy homeostasis via cell-autonomous and -non-autonomous factors in multiple model systems. This mitohormetic effect is thought to involve the mitochondrial unfolded protein response (UPRmt), an adaptive stress-response pathway activated by mitochondrial proteotoxic stress. Using mice with skeletal muscle-specific deficiency of Crif1 (muscle-specific knockout [MKO]), an integral protein of the large mitoribosomal subunit (39S), we identified growth differentiation factor 15 (GDF15) as a UPRmt-associated cell-non-autonomous myomitokine that regulates systemic energy homeostasis. MKO mice were protected against obesity and sensitized to insulin, an effect associated with elevated GDF15 secretion after UPRmt activation. In ob/ob mice, administration of recombinant GDF15 decreased body weight and improved insulin sensitivity, which was attributed to elevated oxidative metabolism and lipid mobilization in the liver, muscle, and adipose tissue. Thus, GDF15 is a potent mitohormetic signal that safeguards against the onset of obesity and insulin resistance.

Effects of Regular and Long-Acting Insulin on Cognition and Alzheimer's Disease Biomarkers: A Pilot Clinical Trial

Abstract: Author(s): Craft, Suzanne; Claxton, Amy; Baker, Laura D; Hanson, Angela J; Cholerton, Brenna; Trittschuh, Emily H; Dahl, Deborah; Caulder, Erin; Neth, Bryan; Montine, Thomas J; Jung, Youngkyoo; Maldjian, Joseph; Whitlow, Christopher; Friedman, Seth | Abstract: BackgroundLong acting insulin detemir administered intranasally for three weeks enhanced memory for adults with Alzheimer's disease dementia (AD) or amnestic mild cognitive impairment (MCI). The investigation of longer-term administration is necessary to determine whether benefits persist, whether they are similar to benefits provided by regular insulin, and whether either form of insulin therapy affects AD biomarkers.ObjectiveThe present study aimed to determine whether four months of treatment with intranasal insulin detemir or regular insulin improves cognition, daily functioning, and AD biomarkers for adults with MCI or AD.MethodsThis randomized, double-blind, placebo-controlled trial included an intent-to-treat sample consisting of 36 adults diagnosed with MCI or mild to moderate AD. Participants received placebo (n = 12), 40 IU of insulin detemir (n = 12), or 40 IU of regular insulin (n = 12) daily for four months, administered with a nasal delivery device. A cognitive battery was administered at baseline and after two and four months of treatment. MRI was administered for all participants and lumbar puncture for a subset (n = 20) at baseline and four months. The primary outcome was change from baseline to four months on a memory composite (sum of Z scores for delayed list and story recall). Secondary outcomes included: global cognition (Alzheimer's Disease Assessment Scale-Cognition), daily functioning (Dementia Severity Rating Scale), MRI volume changes in AD-related regions of interest, and cerebrospinal fluid AD markers.ResultsThe regular insulin treated group had better memory after two and four months compared with placebo (p l 0.03). No significant effects were observed for the detemir-assigned group compared with the placebo group, or for daily functioning for either group. Regular insulin treatment was associated with preserved volume on MRI. Regular insulin treatment was also associated with reduction in the tau-P181/Aβ42 ratio.ConclusionFuture research is warranted to examine the mechanistic basis of treatment differences, and to further assess the efficacy and safety of intranasal insulin.

Perioperative Hyperglycemia Management: An Update.

Abstract: A substantial body of literature demonstrates a clear association between perioperative hyperglycemia and adverse clinical outcomes.1-3 The risk for post-operative complications and increased mortality relates to both long-term glycemic control and to the severity of hyperglycemia on admission and during the hospital stay.2 The underlying mechanism(s) relating hyperglycemia to poor outcomes is not completely understood. Past and current studies point to physiologic changes that occur in the hyperglycemic state that may contribute to poor outcomes. Elevated blood glucose levels impair neutrophil function, cause an overproduction of reactive oxygen species, free fatty acids and inflammatory mediators. These pathophysiologic changes contribute to direct cellular damage, vascular and immune dysfunction.4 Substantial evidence indicates that correction of hyperglycemia with insulin administration reduces hospital complications and decreases mortality in cardiac5 and general surgery patients.6 However, optimal glucose management during the perioperative period is widely debated. Recent randomized controlled trials targeting conventional targets for glycemic control do not demonstrate the significant risk of hypoglycemia7,8 as seen in prior studies using insulin to maintain tight blood glucose control.9 The pendulum of inpatient care has since moved toward more moderate and individualized glycemic targets. This manuscript reports on the prevalence, diagnosis and pathophysiology of perioperative hyperglycemia and provides a practical outline for the management of surgical patients with diabetes and hyperglycemia. Metabolic Consequences of Surgical Stress and Anesthesia During the fasting state, normal subjects maintain plasma glucose levels between 60-100 mg/dl (3.3-5.5 mmol/l). The stress of surgery and anesthesia alters the finely regulated balance between hepatic glucose production and glucose utilization in peripheral tissues. An increase in the secretion of counterregulatory hormones (catecholamines, cortisol, glucagon, and growth hormone) occurs, causing excessive release of inflammatory cytokines including tumor necrosis factor-α, interleukin-6 and interleukin-1β (Figure 1).10 Cortisol increases hepatic glucose production, stimulates protein catabolism and promotes gluconeogenesis, resulting in elevated blood glucose levels.11 Surging catecholamines increase glucagon secretion and inhibit insulin release by pancreatic β-cells.4 Additionally, the increase in stress hormones leads to enhanced lipolysis and high free fatty acid (FFA) concentrations. Increased FFAs have been shown to inhibit insulin-stimulated glucose uptake12 and limit the intracellular signaling cascade in skeletal muscle responsible for glucose transport activity.13 Evidence also suggests that TNF-α interferes with the synthesis and/or translocation of the glucose transporter GLUT-4 reducing glucose uptake in peripheral tissues.14 These processes result in an altered state of insulin action, leading to a relative state of insulin resistance which is most pronounced on the first postoperative day and may persist for 9-21 days following surgery.15 Open in a separate window Figure 1 The Surgical Stress Response

Role of Adipose Tissue Insulin Resistance in the Natural History of Type 2 Diabetes: Results From the San Antonio Metabolism Study.

Abstract: In the transition from normal glucose tolerance (NGT) to type 2 diabetes mellitus (T2DM), the role of β-cell dysfunction and peripheral insulin resistance (IR) is well established. However, the impact of dysfunctional adipose tissue has not been fully elucidated. The aim of this study was to evaluate the role of resistance to the antilipolytic effect of insulin (adipose tissue IR [Adipo-IR]) in a large group of subjects with NGT, impaired glucose tolerance (IGT), and T2DM. Three hundred two subjects with varying glucose tolerance received an oral glucose tolerance test (OGTT) and euglycemic insulin clamp. We evaluated Adipo-IR (fasting and mean OGTT plasma free fatty acid [FFA] × insulin concentrations), peripheral IR (1/[Matsuda index] and (M/I)-1 value), and β-cell function (calculated as the ratio of the increment in plasma insulin to glucose [OGTT/IR (ΔI/ΔG ÷ IR)]). Fasting Adipo-IR was increased twofold in obese subjects with NGT and IGT versus lean subjects with NGT (8.0 ± 1.1 and 9.2 ± 0.7 vs. 4.1 ± 0.3, respectively) and threefold in subjects with T2DM (11.9 ± 0.6; P < 0.001). Progressive decline in ΔI/ΔG ÷ IR was associated with a progressive impairment in FFA suppression during OGTT, whereas the rise in mean plasma glucose concentration only became manifest when subjects became overtly diabetic. The progressive decline in β-cell function that begins in individuals with NGT is associated with a progressive increase in FFA and fasting Adipo-IR.

FoxO integration of insulin signaling with glucose and lipid metabolism

Abstract: The forkhead box O family consists of FoxO1, FoxO3, FoxO4 and FoxO6 proteins in mammals. Expressed ubiquitously in the body, the four FoxO isoforms share in common the amino DNA-binding domain, known as 'forkhead box' domain. They mediate the inhibitory action of insulin or insulin-like growth factor on key functions involved in cell metabolism, growth, differentiation, oxidative stress, senescence, autophagy and aging. Genetic mutations in FoxO genes or abnormal expression of FoxO proteins are associated with metabolic disease, cancer or altered lifespan in humans and animals. Of the FoxO family, FoxO6 is the least characterized member and is shown to play pivotal roles in the liver, skeletal muscle and brain. Altered FoxO6 expression is associated with the pathogenesis of insulin resistance, dietary obesity and type 2 diabetes and risk of neurodegeneration disease. FoxO6 is evolutionally divergent from other FoxO isoforms. FoxO6 mediates insulin action on target genes in a mechanism that is fundamentally different from other FoxO members. Here, we focus our review on the role of FoxO6, in contrast with other FoxO isoforms, in health and disease. We review the distinctive mechanism by which FoxO6 integrates insulin signaling to hepatic glucose and lipid metabolism. We highlight the importance of FoxO6 dysregulation in the dual pathogenesis of fasting hyperglycemia and hyperlipidemia in diabetes. We review the role of FoxO6 in memory consolidation and its contribution to neurodegeneration disease and aging. We discuss the potential therapeutic option of pharmacological FoxO6 inhibition for improving glucose and lipid metabolism in diabetes.

Diabetes in Iran: Prospective Analysis from First Nationwide Diabetes Report of National Program for Prevention and Control of Diabetes (NPPCD-2016).

Abstract: We estimated proportions of different types of diabetes, comorbidities, treatment (the use of oral glucose-lowering agents and insulin), control (hyperglycemia, dyslipidemia and hypertension) and chronic microvascular and macrovascular complications among people with diabetes presenting to the tertiary-care academic diabetes outpatient clinics in Iran. This study is the prospective analysis of data (n = 30,202) from the registry of university-affiliated adult outpatient diabetes clinics in the country during 2015–2016. The proportions of type 1 diabetes, types 2 diabetes, and other types of diabetes were 11.4%, 85.5%, and 1.3%, respectively. The frequencies of drug-naivety, use of oral agents, insulin monotherapy and insulin combination therapy were 2.9%, 60.5%, 11.5%, and 25.1%, respectively. Around 13.2%, 11.9% and 43.3% of patients with diabetes had controlled hyperglycemia, hyperlipidemia and hypertension, respectively. The proportions of retinopathy, nephropathy, peripheral neuropathy, diabetic foot, and ischemic heart disease were 21.9%, 17.6%, 28.0%, 6.2%, and 23.9%, respectively. Despite the wide availability of medications and insulin coverage in Iran, the estimated national control of hyperglycemia, hyperlipidemia and hypertension (especially for young men and old women) remains subpar. The present study further suggests that the frequencies of chronic vascular complications among patients with diabetes are relatively high in Iran.

Hypoxia and H2O2 Dual-Sensitive Vesicles for Enhanced Glucose-Responsive Insulin Delivery

Abstract: A glucose-responsive closed-loop insulin delivery system mimicking pancreas activity without long-term side effect has the potential to improve diabetic patients’ health and quality of life. Here, we developed a novel glucose-responsive insulin delivery device using a painless microneedle-array patch containing insulin-loaded vesicles. Formed by self-assembly of hypoxia and H2O2 dual-sensitive diblock copolymer, the glucose-responsive polymersome-based vesicles (d-GRPs) can disassociate and subsequently release insulin triggered by H2O2 and hypoxia generated during glucose oxidation catalyzed by glucose specific enzyme. Moreover, the d-GRPs were able to eliminate the excess H2O2, which may lead to free radical-induced damage to skin tissue during the long-term usage and reduce the activity of GOx. In vivo experiments indicated that this smart insulin patch could efficiently regulate the blood glucose in the chemically induced type 1 diabetic mice for 10 h.

A New Method for Targeted and Sustained Induction of Type 2 Diabetes in Rodents

Abstract: Type 2 diabetes is a chronic metabolic disorder that is becoming a leading cause of morbidity and mortality. The prolonged time-course of human type 2 diabetes makes modelling of the disease difficult and additional animal models and methodologies are needed. The goal of this study was to develop and characterise a new method that allows controlled, targeted and sustained induction of discrete stages of type 2 diabetes in rodents. Using adult, male rats, we employed a three-week high fat-diet regimen and confirmed development of obesity-associated glucose intolerance, a key feature of human type 2 diabetes. Next, we utilised osmotic mini-pumps to infuse streptozotocin (STZ; doses ranging 80–200 mg/kg) over the course of 14-days to decrease insulin-producing capacity thus promoting hyperglycemia. Using this new approach, we demonstrate a dose-dependent effect of STZ on circulating glucose and insulin levels as well as glucose tolerance, while retaining a state of obesity. Importantly, we found that insulin secretion in response to a glucose load was present, but reduced in a dose-dependent manner by increasing STZ. In conclusion, we demonstrate a novel method that enables induction of discrete stages of type 2 diabetes in rodents that closely mirrors the different stages of type 2 diabetes in humans.