Equivalent insulin resistance in latent autoimmune diabetes in adults (LADA) and type 2 diabetic patients

Latent Autoimmune Diabetes in an Adult Male Presenting With Diabetic Ketoacidosis (DKA)

Latent autoimmune diabetes in adults (LADA) is a common but not well-studied entity and its features overlap between type 1 and type 2 diabetes mellitus (T1D, T2D). Although autoimmunity is a well-known factor associated with this diabetes subtype, environmental factors including excessive weight, physical inactivity, and smoking may also be associated with it. It is commonly misdiagnosed as T2D and generally treated by oral anti-diabetes medications that cause a delay in commencing insulin therapy. There are few cases mentioned in the literature of LADA presenting first time as diabetic ketoacidosis (DKA). Here, we report a case of latent autoimmune diabetes in an adult male who presented with DKA.

Diagnostic Dilemmas and Current Treatment Approaches in Latent Onset Autoimmune Diabetes in Adults: A Concise Review

Latent Onset Autoimmune Diabetes in Adults (LADA) is an autoimmune disorder between T1DM and T2DM and is often misdiagnosed as T2DM due to its late-onset. The disease is characterized by β-cell failure and slow progression to insulin dependence. Early diagnosis is significant in limiting disease progression. C-peptide levels and autoantibodies against β-cells are the most critical diagnostic biomarkers in LADA. The review aims to provide an overview of the biomarkers used to diagnose LADA, and the following treatment approaches. We have summarized LADA's pathophysiology and the autoantibodies involved in the condition, diagnostic approaches, and challenges. There are clear shortcomings concerning the feasibility of autoantibody testing. Finally, we have explored the treatment strategies involved in the management of LADA. In conclusion, the usual management includes treatment with metformin and the addition of low doses of insulin. Newer oral hypoglycaemic agents, such as GLP-1RA and DPP-4 inhibitors, have been brought into use. Since the disease is not entirely understood at the research level and in clinical practice, we hope to encourage further research in this field to assess its prevalence. Large randomized controlled trials are required to compare the efficacy of different available treatment options.

Lifestyle or Environmental Influences and Their Interaction With Genetic Susceptibility on the Risk of LADA

Background

LADA is a common form of diabetes described as a mix between type 1 and type 2 diabetes. Understanding of how genes and environmental factors interact in the development of LADA is central for future efforts to prevent the disease. This review aims to synthesize the literature on lifestyle factors linked to LADA risk and discuss their potential interaction with genetic susceptibility.

Findings

Current knowledge on environmental risk factors for LADA is primarily based on observational data from Scandinavian populations. Increasing evidence suggest that lifestyle factors promoting type 2 diabetes such as obesity, sedentariness, low birth weight and smoking, is implicated in the risk of LADA. Data from mendelian randomization studies support that the link between LADA and obesity, low birth weight and smoking is causal. Limited evidence indicates that dietary factors including consumption of red meat, coffee and sweetened beverages may increase the risk while consumption of alcohol and omega-3 fatty acids may reduce the risk. Several lifestyle factors, including smoking and obesity, seem to interact with human leukocyte antigen genes associated with autoimmunity, conferring much stronger effects on disease risk among those exposed to both factors.

Summary

Available studies suggest that lifestyle modification has the potential for prevention of LADA, particularly for individuals with high risk of disease such as those with genetic susceptibility. Research into risk factors of LADA is however limited, confirmations are warranted, many factors remain to be explored, and there is a need for intervention studies to assess causality.

Latent Autoimmune Diabetes in Adults and Metabolic Syndrome-A Mini Review

Latent autoimmune diabetes in adults (LADA) is a heterogeneous subtype of diabetes characterized by islet cell destruction mediated by islet autoimmunity and insulin resistance. Metabolic syndrome (MetS) is a state in which many risk factors for metabolic and cardiovascular diseases accumulate in an individual. Based on clinical data, this review covers the prevalence of MetS in LADA, focusing on the risk associated with and the role of insulin resistance in the development of LADA from the perspective of inflammatory factors, environmental factors, and the gut microbiota, aiming to improve our understanding of this condition.

Interaction Between GAD65 Antibodies and Dietary Fish Intake or Plasma Phospholipid n-3 Polyunsaturated Fatty Acids on Incident Adult-Onset Diabetes: The EPIC-InterAct Study

OBJECTIVE

Islet autoimmunity is associated with diabetes incidence. We investigated whether there was an interaction between dietary fish intake or plasma phospholipid n-3 polyunsaturated fatty acid (PUFA) concentration with the 65-kDa isoform of GAD (GAD65) antibody positivity on the risk of developing adult-onset diabetes.

RESEARCH DESIGN AND METHODS

We used prospective data on 11,247 incident cases of adult-onset diabetes and 14,288 noncases from the EPIC-InterAct case-cohort study conducted in eight European countries. Baseline plasma samples were analyzed for GAD65 antibodies and phospholipid n-3 PUFAs. Adjusted hazard ratios (HRs) for incident diabetes in relation to GAD65 antibody status and tertiles of plasma phospholipid n-3 PUFA or fish intake were estimated using Prentice-weighted Cox regression. Additive (proportion attributable to interaction [AP]) and multiplicative interactions between GAD65 antibody positivity (≥65 units/mL) and low fish/n-3 PUFA were assessed.

RESULTS

The hazard of diabetes in antibody-positive individuals with low intake of total and fatty fish, respectively, was significantly elevated (HR 2.52 [95% CI 1.76-3.63] and 2.48 [1.79-3.45]) compared with people who were GAD65 antibody negative and had high fish intake, with evidence of additive (AP 0.44 [95% CI 0.16-0.72] and 0.48 [0.24-0.72]) and multiplicative (P = 0.0465 and 0.0103) interactions. Individuals with high GAD65 antibody levels (≥167.5 units/mL) and low total plasma phospholipid n-3 PUFAs had a more than fourfold higher hazard of diabetes (HR 4.26 [2.70-6.72]) and an AP of 0.46 (0.12-0.80) compared with antibody-negative individuals with high n-3 PUFAs.

CONCLUSIONS

High fish intake or relative plasma phospholipid n-3 PUFA concentrations may partially counteract the increased diabetes risk conferred by GAD65 antibody positivity.

Improved insulin sensitivity with sodium-glucose cotransporter 2 inhibitor treatment in a patient with slowly progressive type 1 diabetes mellitus with metabolic syndrome: a case report

We herein report the clinical course of a 56-year-old Japanese patient with slowly progressive type 1 diabetes mellitus, metabolic syndrome, non-alcoholic fatty liver disease, and severe insulin resistance. The patient's intravenous glucose tolerance test indicated marked reductions in insulin sensitivity and endogenous insulin secretion. Accordingly, administration of ipragliflozin l-proline, a sodium-glucose cotransporter 2 inhibitor, promoted improvements in insulin sensitivity and blood glucose levels, as well as a decrease in visceral fat, improvement in dyslipidemia, and decrease in hepatic lipid content, suggesting the potential efficacy of sodium-glucose cotransporter 2 inhibitors for obese patients with type 1 diabetes mellitus exhibiting insulin resistance.

Latent Autoimmune Diabetes in Adults (LADA) and its Metabolic Characteristics among Yemeni Type 2 Diabetes Mellitus Patients

PURPOSE

Although there is ample data about the prevalence of diabetes in the Middle East, little is known about the prevalence and features of autoimmune diabetes in this region. The aim of this study was to investigate the prevalence and metabolic characteristics of latent autoimmune diabetes in adults (LADA) amongst Yemeni Type 2 DM patients.

PATIENTS AND METHODS

In this cross-section study, 270 Type 2 DM patients aged 30-70 years were recruited from the National Diabetes Center, Al-Thowra Hospital, Sana'a city, during the period November 2015 to August 2016. All Type 2 DM patients were diagnosed within 5 years and who did not require insulin for a minimum of 6 months following diagnosis. Levels of glutamic acid decarboxylase autoantibodies (GADA) were measured in all patients, and LADA was diagnosed in patients testing positive for anti-GAD antibodies. Further, biochemical analysis was carried out including fasting blood glucose (FBG), glycated haemoglobin (HbA1c), insulin, and lipid profile. Insulin resistance (HOMA-IR) and β-cell function (HOMA-β) were calculated.

RESULTS

The prevalence of LADA, as defined by GADA-positive, amongst patient with Type 2 DM was 4.4%; with no significant difference in the prevalence between male (5.8%) and female (3.4%). LADA patients were younger than GADA-negative Type 2 DM. Body mass index, waist circumference, insulin and HOMA-β were significantly lower in LADA patients, whereas triglyceride, cholesterol, HDL-c and HOMA-IR were non-significantly lower with respect to Type 2 DM. In contrast, FBG and HbA1c were significantly higher in LADA patients. Moreover, the prevalence of metabolic syndrome was significantly lower in LADA as compared with Type 2 DM. Only 2 out of the 12 GADA-positive (16.7%) were on insulin treatment at the time of the study.

CONCLUSION

The prevalence of LADA in Yemeni Type 2 DM is lower than many of those reported in the literature, with no gender preference. Metabolic syndrome was significantly lower in LADA patients. Patients with LADA share insulin resistance with Type 2 DM but display a more severe defect in β-cell function, thus highlighting the importance of an early diagnosis of LADA, to correctly treat LADA patients, allowing safe and effective therapies.

Longitudinal changes in insulin resistance in children with epilepsy on ketogenic diet: Prevalence and risk factors

INTRODUCTION

The aim of the study was to evaluate the incidence of insulin resistance (IR) and the associated risk factors in children with epilepsy on a ketogenic diet (KD).

METHODS

This longitudinal cohort study analyzed data of children with epilepsy on KD. Insulin resistance was assessed using the homeostasis model assessment of insulin resistance (HOMA-IR). The HOMA-IR value, fasting serum insulin levels, fasting glucose (FG) levels, and lipid profiles were measured before the initiation of the KD and at 6- to 12-month intervals.

RESULTS

A total of 28 children were enrolled. The median age at the initiation of KD was 2.7 ± 2.4 years, and the median follow-up duration was 2.1 ± 1.4 years. The median HOMA-IR (HOMA-IR-1) value before the initiation of KD was 1.2 ± 0.2, which significantly increased to 1.8 ± 0.3 at the last follow-up (HOMA-IR-2; ∆HOMA-IR = 0.6 ± 0.3, p < 0.001). The following factors were associated with patients with higher HOMA-IR-2 values (≥1.9): younger age at seizure onset (0.3 ± 0.2 years, p < 0.001), at the initiation of antiepileptic drugs (AEDs; 0.3 ± 0.3 years, p < 0.001), and at the initiation of KD (1.3 ± 0.5 years, p < 0.001) and higher serum alanine transaminase (ALT; 84.0 ± 17.8 U/L, p = 0.022), total cholesterol (TC; 245.0 ± 20.1 mg/dL, p = 0.001), low-density lipoprotein cholesterol (LDL-C, 103.0 ± 6.7 mg/dL, p = 0.003), and triglyceride (387.0 ± 28.8 mg/dL, p < 0.001) levels. Multivariate regression analysis revealed that the age at seizure onset (p = 0.002), at initiation of AEDs (p = 0.021), and at initiation of KD (p = 0.022) and serum levels of LDL-C (p = 0.012) and triglycerides (p = 0.026) were associated with a significantly high HOMA-IR-2 value.

CONCLUSION

Close monitoring of serum lipids levels, especially at younger age, may aid in detecting exacerbation of IR.

Auto-reactivity against gut bacterial peptides in patients with late-onset diabetes

The depletion of gut mucosal barrier enables exposure of gut microbes/gut microbial products to the host mucosal immunity which may increase the risk of metabolic/inflammatory disorders. These immune responses can lead to the development of mild autoimmunity to metabolic peptides coming from gut bacteria and may result in metabolic diseases like late-onset diabetes (LOD). In the present study, we identified host sera cross-reactivity with gut bacterial peptides similar to host proteins. The interaction between diabetic sera and gut peptides was detected by enzyme-linked immunosorbent assay (ELISA) and results were confirmed using surface plasmon resonance (SPR). The ELISA assay showed a higher level of serum cross-reactivity in LOD patients as compared to non-diabetic controls against three peptides (P-5, P-9, and P-13). SPR analysis confirmed binding-affinity against P-5 and P-13. Also, a significant correlation was observed between inflammatory markers and P-5. This study demonstrates that gut health is important not only for intestinal diseases but also for several late-onset diseases, like, diabetes.

Altered peripheral nerve structure and function in latent autoimmune diabetes in adults

AIM

The present study was undertaken to investigate mechanisms of peripheral nerve dysfunction in latent autoimmune diabetes in adults (LADA).

MATERIALS AND METHODS

Participants with LADA (n = 15) underwent median nerve ultrasonography and nerve excitability to examine axonal structure and function, in comparison to cohorts of type 1 diabetes (n = 15), type 2 diabetes (n = 23) and healthy controls (n = 26). The LADA group was matched for diabetes duration, glycaemic control, and neuropathy severity with the type 1 and type 2 diabetes groups. A validated mathematical model of the human axon was utilized to investigate the pathophysiological basis of nerve dysfunction.

RESULTS

The most severe changes in nerve structure and function were noted in the LADA group. The LADA cohort demonstrated a significant increase in nerve cross-sectional area compared to type 1 participants and controls. Compared to type 1 and 2 diabetes, measures of threshold electrotonus, which assesses nodal and internodal conductances, were significantly worse in LADA in response to both depolarising currents and hyperpolarising currents. In the recovery cycle, participants with LADA had a significant increase in the relative refractory period. Mathematical modelling of excitability recordings indicated the basis of nerve dysfunction in LADA was different to type 1 and 2 diabetes.

CONCLUSIONS

Participants with LADA exhibited more severe changes in nerve function and different underlying pathophysiological mechanisms compared to participants with type 1 or 2 diabetes. Intensive management of risk factors to delay the progression of neuropathy in LADA may be required.

Integrated analysis of gene modulation profile identifies pathogenic factors and pathways in the liver of diabetic mice

Purpose

Type-2 diabetes mellitus (T2D) is a metabolic disorder that can progress to a serious chronic disease and frequently develops in obese individuals in association with various pathogenic complications that shorten the lifespan of these patients. The liver is an important organ regulating lipid metabolism, which is damaged in both obesity and T2D; however, the specific pathways involved in these pathogenic effects remain unclear. Establishing a suitable animal model that effectively mimics the human biological condition is a critical factor to allow for precise identification of T2D-related genes.

Methods

The KK.Cg-A^y mouse strain is one such model that has offered insight into obesity-related T2D pathogenesis. To comprehensively assess the association between obesity and T2D, in the present study, we performed microarray analysis on liver tissue samples of KK.Cg-A^y and KK-α/α wild-type mice to examine differences in gene expression and methylation patterns and their related biological processes and pathways.

Results

We found that inflammation accompanied by abnormal lipid metabolism led to the spontaneous mechanism of obesity-induced diabetes, resulting in differential expression of some genes related to the terms of insulin resistance and glucose tolerance. Surprisingly, disruption of steroid biosynthesis strongly facilitated the diabetic pathogenesis. To support these findings, we highlighted some candidate genes and determined their relationships in biological networks of obesity-induced T2D.

Conclusion

These findings provide valuable reference data that can facilitate further detailed investigations to elucidate the pathogenic mechanism of obesity-induced diabetes in mice, which can be associated with the human condition to inform new prevention and treatment strategies.

Past, present and future of latent autoimmune diabetes in adults

Latent autoimmune diabetes in adults (LADA) is the most common form of autoimmune diabetes diagnosed in adults. Similar to type 1 diabetes, the prevalence of LADA is impacted by ethnicity and geography. LADA is characterized by β cell loss due to autoimmunity and insulin resistance and has highly heterogeneous clinical features, autoimmunity, and genetics in a glutamic acid decarboxylase antibody (GADA) titre-dependent manner, suggesting LADA is part of a continuum spectrum between type 1 and type 2 diabetes. Although LADA is the most frequent form of autoimmune diabetes diagnosed in adults, clinical trials involving LADA are scarce. Here we review the recent advancements in LADA epidemiology, clinical features, pathogenesis, and interventions. We also highlight the environmental factors that are thought to play an important role in addition to genetics in the pathogenesis of LADA. In the future, high-throughput molecular profiles might shed light on the nature of LADA among the wide spectrum of diabetes and offer new opportunities to identify novel LADA-specific biomarkers.

Pathophysiological characteristics in patients with latent autoimmune diabetes in adults using clamp tests: evidence of a continuous disease spectrum of diabetes

AIMS

This study aimed to assess islet insulin secretion and insulin resistance in Chinese patients with latent autoimmune diabetes in adults (LADA).

METHODS

Twelve patients with LADA, 10 with type 1 diabetes mellitus (T1DM), 10 with type 2 diabetes mellitus (T2DM), and 10 nondiabetic healthy controls (HCs) were included. Patients with LADA were subtyped according to the glutamic acid decarboxylase antibody (GADA) titer (LADA1, GADA titer ≥ 180 U/mL; LADA2, GADA titer 18-180 U/mL). Insulin secretion and sensitivity were assessed using hyperglycemic and hyperinsulinemic-euglycemic clamp tests, respectively.

RESULTS

The first-phase insulin secretion gradually increased in patients with T1DM, LADA1, LADA2, and T2DM to HCs (29.32 ± 6.00 mU/L vs. 68.71 ± 4.50 mU/L vs. 87.60 ± 11.60 mU/L vs. 138.27 ± 13.18 mU/L vs. 248.49 ± 21.97 mU/L; P < 0.05). The second-phase insulin secretion (2 ph) and maximum insulin secretion (MIS) were significantly lower in patients with LADA2 and T2DM than in HCs, but higher in those with LADA1 and T1DM. No significant differences in 2 ph and MIS were observed between patients with LADA1 and T1DM, and between those with LADA2 and T2DM. The levels of insulin sensitivity index (ISI) during hyperinsulinemic-euglycemic clamps were lower in patients with LADA and T2DM than in those with T1DM. Patients with T1DM displayed lower ISI compared with HCs.

CONCLUSIONS

Chinese patients with LADA and T1DM had impaired insulin sensitivity and β-cell function. Furthermore, the hypothesis that diabetes is a continuous spectrum from T1DM, LADA1, LADA2 to T2DM was confirmed in this study.

Etiology and Pathogenesis of Latent Autoimmune Diabetes in Adults (LADA) Compared to Type 2 Diabetes

As the heterogeneity of diabetes is becoming increasingly clear, opportunities arise for more accurate assessment of factors influencing disease onset, which may lead to more efficient primary prevention. LADA - latent autoimmune diabetes in adults - is a common, hybrid form of diabetes with features of both type 1 and type 2 diabetes. This review aims to summarize current knowledge on the pathophysiological and etiological overlap and differences between LADA and type 2 diabetes, discuss similarities between LADA and type 1 diabetes and point at future research needs. Studies conducted to date show a clear genetic overlap between LADA and type 1 diabetes with a high risk conferred by variants in the human leukocyte antigen (HLA) region. In contrast, data from the limited number of studies on lifestyle factors available indicate that LADA may share several environmental risk factors with type 2 diabetes including overweight, physical inactivity, alcohol consumption (protective) and smoking. These factors are known to influence insulin sensitivity, suggesting that insulin resistance, in addition to insulin deficiency due to autoimmune destruction of the beta cells, may play a key role in the pathogenesis of LADA. Moreover, this implies that onset of LADA, similar to type 2 diabetes, to some extent could be prevented or postponed by lifestyle modification such as weight reduction and increased physical activity. The preventive potential of LADA is an important topic to elucidate in future studies, preferably intervention studies.

Alterations of Sphingolipid Metabolism in Different Types of Polycystic Ovary Syndrome

The roles of sphingolipids in polycystic ovary syndrome (PCOS) are still unknown. This study aimed to investigate the sphingolipid characteristics for different types of PCOS using liquid chromatography-mass spectrometry (LC-MS). A total of 107 women with PCOS and 37 healthy women as normal controls were studied. PCOS patients were further classified into non-obesity with insulin resistance (IR) (NOIR), obesity with IR (OIR), and non-obesity and non-IR (NIR) subgroups. A total of 87 serum sphingolipids, including 9 sphingosines, 3 sphinganines, 1 sphingosine-1-phosphate (S1P), 19 ceramides (Cers), 1 ceramide-1-phosphate, 44 sphingomyelins (SMs), 4 hexosylceramides, and 6 lactosylceramides (LacCers) were analyzed using an improved sphingolipidomic approach based on LC-MS. Notable elevations in the levels of S1P, Cer, and SM were observed in PCOS patients when compared with healthy women, and SM species with long saturated acyl chains showed potential as novel biomarkers of PCOS. In addition, the level of LacCer was only elevated in NIR, and there was almost no change in NOIR and OIR. This study is the first to report the comprehensive sphingolipidomic profiling of different subgroups of PCOS with or without IR or obesity and suggests that serum sphingolipids might be useful as diagnostic biomarkers for different types of PCOS.

Advanced glycation end-product cross-linking inhibits biomechanical plasticity and characteristic failure morphology of native tendon

Advanced glycation end-products (AGEs) are formed in vivo from the nonenzymatic reaction between sugars and proteins. AGEs accumulate in long-lived tissues like tendons, cross-linking neighboring collagen molecules, and are in part complicit in connective tissue pathologies experienced in aging and with diabetes. We have previously described discrete plasticity: a characteristic form of nanoscale collagen fibril damage consisting of serial fibril kinking and collagen denaturation that occurs in some mechanically overloaded tendons. We suspect that this failure mechanism may be an adaptive trait of collagen fibrils and have published evidence that inflammatory cells may be able to recognize and digest the denatured collagen produced by overload. In this study, we treated bovine tail tendons with ribose to simulate long-term AGE cross-linking in vitro. We hypothesized that a high degree of cross-linking would inhibit the intermolecular sliding thought to be necessary for discrete plasticity to occur. Tendons were mechanically overloaded, and properties were investigated by differential scanning calorimetry and scanning election microscopy. Ribose cross-linking treatment altered the mechanical response of tendons after the yield point, significantly decreasing postyield extensibility and strain energy capacity before rupture. Coincident with altered mechanics, ribose cross-linking completely inhibited the discrete plasticity failure mechanism of tendon. Our results suggest that discrete plasticity, which may be an important physiological mechanism, becomes pathologically disabled by the formation of AGE cross-links in aging and diabetes. NEW & NOTEWORTHY We have previously shown that mechanically overloaded collagen fibrils in mammalian tendons accrue nanoscaled damage. This includes development of a characteristic kinking morphology within a shell of denatured collagen: discrete plasticity. Here, using a ribose-incubation model, we show that advanced glycation end-product cross-linking associated with aging and diabetes completely inhibits this mechanism. Since discrete plasticity appears to cue cellular remodeling, this result has important implications for diabetic tendinopathy.

Genome-Wide Meta-analysis of Gene-Environmental Interaction for Insulin Resistance Phenotypes and Breast Cancer Risk in Postmenopausal Women

Insulin resistance (IR)-related genetic variants are possibly associated with breast cancer, and the gene-phenotype-cancer association could be modified by lifestyle factors including obesity, physical inactivity, and high-fat diet. Using data from postmenopausal women, a population highly susceptible to obesity, IR, and increased risk of breast cancer, we implemented a genome-wide association study (GWAS) in two steps: (1) GWAS meta-analysis of gene-environmental (i.e., behavioral) interaction (G*E) for IR phenotypes (hyperglycemia, hyperinsulinemia, and homeostatic model assessment-insulin resistance) and (2) after the G*E GWAS meta-analysis, the identified SNPs were tested for their associations with breast cancer risk in overall or subgroup population, where the SNPs were identified at genome-wide significance. We found 58 loci (55 novel SNPs; 5 index SNPs and 6 SNPs, independent of each other) that are associated with IR phenotypes in women overall or women stratified by obesity, physical activity, and high-fat diet; among those 58 loci, 29 (26 new loci; 2 index SNPs and 2 SNPs, independently) were associated with postmenopausal breast cancer. Our study suggests that a number of newly identified SNPs may have their effects on glucose intolerance by interplaying with obesity and other lifestyle factors, and a substantial proportion of these SNPs' susceptibility can also interact with the lifestyle factors to ultimately influence breast cancer risk. These findings may contribute to improved prediction accuracy for cancer and suggest potential intervention strategies for those women carrying genetic risk that will reduce their breast cancer risk.

Association of self-reported sedentary time with insulin resistance among Korean adults without diabetes mellitus: a cross-sectional study

Background

A more sedentary lifestyle can result in insulin resistance. However, few research studies have assessed the association between insulin resistance and sedentary lifestyle in Asian populations. Therefore, this study aimed to investigate the association of sedentary time with insulin resistance. In addition, we also investigate the moderate effect of employment status, moderate-to-vigorous physical activity (MVPA), and body mass index (BMI) in this association.

Methods

Data from 2573 individuals who participated in the 2015 Korean National Health and Nutrition Examination Survey were analyzed. Sedentary time was measured using self-administered questionnaires, and IR data were estimated using the homeostasis model assessment–insulin resistance index (HOMA-IR). Adjusted odds ratio (OR) and 95% confidence intervals (CIs) from a multivariable logistic regression model were generated for all participants. Subgroup analysis was only performed between sedentary time and HOMA-IR stratified by employment status, because moderate effects were not significant in the tests for interaction for MVPA and BMI. For all analyses, the individuals were categorized as having high or normal HOMA-IR values (> 1.6 and ≤ 1.6, respectively).

Results

A HOMA-IR > 1.6 was observed in 40.3% of the sedentary time Q1 (low) group (< 5.0 h/day), 41.4% of the sedentary time Q2 (middle-low) group, 44.2% of the sedentary time Q3 (middle-high) group, and 48.4% of the sedentary time Q4 (high) group (≥10.0 h/day). When the low level sedentary time group was used as the reference group, the high level sedentary time group was significantly associated with high IR value (HOMA-IR > 1.6) (OR = 1.40, 95% CI: 1.060–1.838). However, this association was not significant across the other sedentary time groups. Moreover, participants reporting a high sedentary time and were employed had 1.67 times the odds of having a high IR value (HOMA-IR > 1.6) compared to those who reported having a low sedentary time and were employed (OR = 1.67, 95% CI: 1.184–2.344). In the unemployed participants, sedentary time was not associated with IR.

Conclusions

High sedentary time (≥10.0 h/day) was associated with elevated HOMA-IR among Korean adults without diabetes mellitus. Furthermore, the association between high sedentary time and HOMA-IR values was more pronounced in the employed population.

A new chromanone isolated from Portulaca oleracea L. increases glucose uptake by stimulating GLUT4 translocation to the plasma membrane in 3T3-L1 adipocytes

Three homoisoflavonoids and one dimethoxychalcone from Portulaca oleracea L. were isolated using bioassay-guided fractionation and HPLC. Among the compounds 1-4, (E)-5-hydroxy-7-methoxy-3-(2'-hydroxybenzyl)-4-chromanone (compound 3) had the most effect on glucose uptake in the adipocytes. We investigated how (E)-5-hydroxy-7-methoxy-3-(2'-hydroxybenzyl)-4-chromanone contributed to increase glucose uptake in 3T3-L1 adipocytes. Levels of the glucose transporters GLUT-4, as well as glucose uptake, and key proteins of the insulin pathway, namely PI3K/AKT and AMPK pathway are analyzed using glucose uptake assay and western blot analysis. Our results show that (E)-5-hydroxy-7-methoxy-3-(2'-hydroxybenzyl)-4-chromanone significantly increased glucose uptake by stimulating translocation of GLUT4 to the plasma membrane in 3T3-L1 adipocytes. High levels of expression of GLUT4 in the plasma membrane resulted from IRS-1 phosphorylation, PI3K activation, Akt phosphorylation and phosphorylation of AMPK, resulting in increased glucose uptake by the cells. The increase in glucose uptake due to (E)-5-hydroxy-7-methoxy-3-(2'-hydroxybenzyl)-4-chromanone was significantly inhibited by the PI3K inhibitor and the AMPK inhibitor in 3T3-L1 adipocytes. These findings suggest that (E)-5-hydroxy-7-methoxy-3-(2'-hydroxybenzyl)-4-chromanone may increase glucose uptake by stimulating GLUT4 translocation to the plasma membrane via activating the PI3K/Akt and AMPK pathways in 3T3-L1 adipocytes.

Feruloylated oligosaccharides from maize bran alleviate the symptoms of diabetes in streptozotocin-induced type 2 diabetic rats

This study investigated the therapeutic effect of feruloylated oligosaccharides (FOs) extracted from maize bran on type 2 diabetic rats and its potential mechanism. Streptozotocin (STZ) induced type 2 diabetic male rats were orally administered with different levels of FOs for 8 weeks, and ferulic acid (FA) treatment was conducted as the positive control. Among all the treatments, the oral administration of 600 mg per kg bw per d FOs showed the best therapeutic effects on the diabetic rats by significantly lowering the levels of fasting plasma glucose (FPG), fasting insulin, TG, LDL-c, aspartate transaminase, creatine kinase and lactate dehydrogenase in plasma, while increasing the level of plasma HDL-c. In addition, the intake of FOs at 600 mg per kg bw per d exhibited the best antioxidant effects in the plasma, liver, kidney and heart of the diabetic rats, and the highest inhibitory effects on the formation of AGEs and CML in the organs, which might explain the alleviating effects of FOs on abdominal aorta injury observed in the current study. FOs presented better regulation effects on FPG, plasma lipid and the protection of abdominal aorta than FA under the same administered dosage. Based on these outcomes, FOs from maize bran could be beneficial for prevention or early treatment of diabetes mellitus.

Interleukin-18 serum level is elevated in type 2 diabetes and latent autoimmune diabetes

BACKGROUND

Interleukin-18 (IL-18) is an inflammatory cytokine found to be elevated in obesity, metabolic syndrome and type 2 diabetes (T2D) as a part of the chronic low-grade inflammatory process in these states. The aim of the study was to evaluate the interleukin level in patients with latent autoimmune diabetes of the adults (LADA) in comparison to that in T2D subjects.

MATERIALS AND METHODS

IL-18 was analyzed through enzyme-linked immunosorbent assay in 76 participants with T2D and 24 with LADA and 14 control subjects. Evaluation was also carried out in body mass index (BMI)- and glycemic control-matched diabetic patients.

RESULTS

The serum concentration of IL-18 was higher in patients with T2D (389.04 ± 203.44 pg/mL) and LADA (327.04 ± 144.48 pg/mL) than that in control subjects (219.88 ± 91.03 pg/mL), P < 0.05. However, it was not significantly different between both diabetic groups (P = 0.255) despite higher IL-6 (4.78 ± 5.84 vs 1.79 ± 0.96 pg/mL, P < 0.001) and hs-CRP (2.60 ± 1.70 vs 1.29 ± 1.20 mg/L, P = 0.002) level in T2D patients. The results were persistent in BMI-matched subjects with diabetes (IL-18 = 403.48 ± 226.32 vs 329.30 ± 146.30 pg/mL, respectively for T2D and LADA, P = 0.391). The correlations in T2D group concerning HDL cholesterol (r = -0.377, P = 0.001), postprandial glucose (r = 0.244, P = 0.043), IL-6 (r = 0.398, P < 0.001) and hs-CRP (r = 0.427, P = 0.001) were not confirmed in LADA and control subjects.

CONCLUSION

The IL-18 serum level was higher in T2D and LADA than that in control subjects, but did not differ between both diabetic groups, even when they were BMI matched. Correlations with lipid, glycemic and inflammatory parameters were present in T2D only.

Membrane Aging as the Real Culprit of Alzheimer's Disease: Modification of a Hypothesis

Our previous studies proposed that Alzheimer's disease (AD) is a metabolic disorder and hypothesized that abnormal brain glucose metabolism inducing multiple pathophysiological cascades contributes to AD pathogenesis. Aging is one of the great significant risk factors for AD. Membrane aging is first prone to affect the function and structure of the brain by impairing glucose metabolism. We presume that risk factors of AD, including genetic factors (e.g., the apolipoprotein E ε4 allele and genetic mutations) and non-genetic factors (such as fat, diabetes, and cardiac failure) accelerate biomembrane aging and lead to the onset and development of the disease. In this review, we further modify our previous hypothesis to demonstrate "membrane aging" as an initial pathogenic factor that results in functional and structural alterations of membranes and, consequently, glucose hypometabolism and multiple pathophysiological cascades.

Interaction between pancreatic β cell and electromagnetic fields: A systematic study toward finding the natural frequency spectrum of β cell system

Interaction between biological systems and environmental electric or magnetic fields has gained attention during the past few decades. Although there are a lot of studies that have been conducted for investigating such interaction, the reported results are considerably inconsistent. Besides the complexity of biological systems, the important reason for such inconsistent results may arise due to different excitation protocols that have been applied in different experiments. In order to investigate carefully the way that external electric or magnetic fields interact with a biological system, the parameters of excitation, such as intensity or frequency, should be selected purposefully due to the influence of these parameters on the system response. In this study, pancreatic β cell, the main player of blood glucose regulating system, is considered and the study is focused on finding the natural frequency spectrum of the system using modeling approach. Natural frequencies of a system are important characteristics of the system when external excitation is applied. The result of this study can help researchers to select proper frequency parameter for electrical excitation of β cell system. The results show that there are two distinct frequency ranges for natural frequency of β cell system, which consist of extremely low (or near zero) and 100-750 kHz frequency ranges. There are experimental works on β cell exposure to electromagnetic fields that support such finding.

Effects of Weight Reduction After Sleeve Gastrectomy on Metabolic Variables in Saudi Obese Subjects in Aseer Province of Kingdom of Saudi Arabia

OBJECTIVES

The objectives of this study were to investigate the occurrence of oxidative stress, status of protective antioxidants enzymes, inflammatory biomarkers, and some metabolic health variables in the blood and to compare the results between those of the normal controls and obese patients submitted to sleeve gastrectomy-induced weight loss over a 1-year follow-up period.

MATERIALS AND METHODS

A prospective study was conducted in Aseer Central Hospital and Abha Private Hospital in the Kingdom of Saudi Arabia from January 2012 to January 2013 on 50 normal (BMI = 22-25 kg/m²) control subjects and 50 obese (BMI = 45-50 kg/m²) patients. A subset of 20 men and 80 women patients, aged 20-45 years, was included. The systemic blood cell counts were determined by Beckman Coulter UniCel analyzer. The occurrence of oxidative stress, the status of antioxidant enzyme system in the blood, levels of serum hepatic enzymes, cardiovascular risk factors, and serum sodium, potassium, copper, and zinc levels were determined by spectrophotometric procedures. The concentration of TSH and T₄ were analyzed by Siemens Immunoassay System.

RESULTS

Group 1 (Obese: preoperative) This group compared with the normal controls exhibited significant (p < 0.05) increase in inflammatory biomarkers, a significant (p < 0.05) rise in hepatic enzymes, a significant (p < 0.05) decrease in serum total bilirubin. Concentration of serum total cholesterol (TC), triacylglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and fasting blood glucose(FBG) were significantly (p < 0.05) increased, but HDL cholesterol (HDL-C) was significantly depleted (p < 0.05). Serum urea and creatinine contents were significantly (p < 0.05) decreased. Serum copper and zinc levels were significantly (p < 0.05) increased. Group 2: Sleeve Gastrectomy Surgery (Obese: postoperative) This group compared with the obese group, preoperatively, demonstrated a profound reduction in body weight (-32%) as well as in BMI (-29%). Serum malondialdehyde, a stress index, was significantly (p < 0.001) inhibited and conversely, activities of antioxidant enzymes: superoxide dismutase(Cu-Zn SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PDH), and vitamin C, were remarkably (p < 0.001) increased. Furthermore, remarkable improvements in deranged metabolic variables approaching normality were discernible. Inflammatory biomarkers in the blood and hepatic enzymes in serum were significantly (p < 0.001) decreased. Levels of TC, TG, LDL-C, FBG, and HDL-C in serum exhibited significant (p < 0.05) reductions, a reversal toward normality. Serum albumin and total bilirubin concentrations were significantly increased (p < 0.001). Serum sodium, potassium, copper, zinc, and TSH levels were significantly (p < 0.001) decreased.

CONCLUSIONS

Obesity is a chronic disease of multifactorial origin and resulted in perturbations of whole body metabolism in this study. It is thus likely that this imbalance was associated with an inhibition in protective antioxidants and occurrence of oxidative stress. The staging concept of sleeve gastrectomy is a safe and effective approach with remarkable efficacy in sustaining weight loss and bringing back normal metabolism of variables in tissues over a 1-year follow-up period.

Latent autoimmune diabetes in adults (LADA) in Asian and European populations

Diabetes mellitus is a chronic disorder caused by relative or absolute insulin deficiency and characterized by chronic hyperglycaemia. It is expected that by year 2025, 80% of all type 2 diabetic patients will be living in developing or low- and middle-income countries. Among Asians, there has been an overall increase in abdominal obesity; however, the risk of diabetes in these populations starts at much lower body mass index as compared to Caucasians. A significant proportion of diabetic patients with adult-onset, initially nonrequiring insulin treatment, have diabetes-associated autoantibodies in their sera. A new subclass of diabetes with the designation of latent autoimmune diabetes of adult-onset (LADA) has been proposed for this category of subjects. Studies have demonstrated that patients with autoimmune diabetes, characterized by the presence of glutamic decarboxylase autoantibodies display a different clinical phenotype from classical type 2 diabetes without glutamic decarboxylase autoantibodies. This subset of phenotypic type 2 diabetes subjects with islet autoantibodies tend to have sulphonylurea failure and need insulin treatment earlier in the disease process. Diagnosing LADA at an initial stage will be important so that insulin can be initiated earlier, facilitating improved glycemic control sooner as well as the preservation of residual beta-cell function in adult-onset autoimmune diabetes. Because of differences in dietary habits, environmental factors, and phenotypic characteristics between European and Asian populations, there may be heterogeneity in the prevalence and other characteristics of LADA in these two populations.

Effects of supervised structured aerobic exercise training program on fasting blood glucose level, plasma insulin level, glycemic control, and insulin resistance in type 2 diabetes mellitus

Objective:

To determine the effects of supervised structured aerobic exercise training (SSAET) program on fasting blood glucose level (FBGL), plasma insulin level (PIL), glycemic control (GC), and insulin resistance (IR) in type 2 diabetes mellitus (T2DM).

Methods:

Riphah Rehabilitation and Research Centre (RRRC) was the clinical setting for this randomized controlled trial, located at Pakistan Railways General Hospital (PRGH), Rawalpindi, Pakistan. Study duration was 18 months from January 1, 2015 to June 30, 2016. Patients of both genders ranging 40-70 years of age with at least one year of history of T2DM were considered eligible according to WHO criteria, while patients with other chronic diseases, history of smoking, regular exercise and diet plan were excluded. Cohorts of 195 patients were screened out of whom 120 fulfilled the inclusion criteria. Amongst them 102 agreed to participate and were assigned to experimental (n=51) and control (n=51) groups. Experimental group underwent SSAET program, routine medication and dietary plan, whereas the control group received routine medication and dietary plan, while both group received treatment for 25 weeks. The blood samples were taken at baseline and on the completion of 25 weeks. The investigation of fasting blood glucose level, plasma insulin level, and glycemic control was conducted to calculate IR.

Results:

Patients with T2DM in experimental group (n=51) treated with SSAET program, routine medication and dietary plan significantly improved FBGL (pre-mean= 276.41±25.31, post-mean=250.07±28.23), PIL (pre-mean=13.66±5.31, post-mean=8.91±3.83), GC (pre-mean=8.31±1.79, post-mean 7.28±1.43), and IR (pre-mean=64.95±27.26, post-mean 37.97±15.58), as compared with patients in control group treated with routine medication and dietary plan in whom deteriorations were noted in FBGL (pre-mean=268.19±22.48, post-mean=281.41±31.30), PIL(pre-mean=14.14±5.48, post-mean=14.85±5.27) GC (pre-mean=8.15±1.74, post-mean=8.20±1.44, and IR (pre-mean=64.49±23.63. post-mean=70.79 ±23.30). Statistically at the baseline the results were not significant (p>0.05), but at the completion of 25 weeks intervention all the variable showed significant results (p<0.05.

Conclusion:

It is concluded that a 25 weeks SSAET program along with routine medical management is more effective treatment in the management of fasting blood glucose level, glycemic control, plasma insulin level and insulin resistance as compared with routine medical management and dietary plan in the management of T2DM.

Altered Regional Gray Matter Volume in Obese Men: A Structural MRI Study

Obesity is associated with a number of health problems, especial insulin resistance and Type 2 diabetes. Our previous study showed that obese males had decreased neural activity in the orbital frontal cortex (OFC) and increased activity in the left putamen (Zhang et al., 2015b), which could indicate altered eating behaviors in obesity related to a hyper-functioning striatum and hypo-functioning inhibitory control. Accordingly, our goal of the current study was to determine whether there are alterations in the brain structures within these two neural systems in obese individuals. Twenty obese men (age: 20–28 years) and 20 age-matched lean male subjects were involved in the current study. Plasma glucose and insulin were tested during hunger state, and homeostasis model assessment of insulin resistance (HOMA-IR) was based on the blood samples. In the study, we used structural MRI and a voxel-based morphometry (VBM) method to investigate regional structures in obese subjects and find out whether there are correlations between the insulin and the brain structures. We found that obese men only showed a significantly increased gray matter volume (GMV) in the left putamen and that the GMV of the left putamen was positively correlated with body mass index, plasma insulin and HOMA-IR. The putamen is a core region participating in insulin signal regulation, and our results showed an abnormal GMV of the putamen is a core alternation in aberrant insulin. Furthermore, the GMV of the OFC was negatively correlated with hunger rating, despite there being no significant difference between the two groups in the OFC. In conclusion, the altered structure and function of the putamen could play important roles in obesity and aberrant insulin.

Prevalence of Positive Diabetes-Associated Autoantibodies among Type 2 Diabetes and Related Metabolic and Inflammatory Differences in a Sample of the Bulgarian Population

BACKGROUND

The study aimed to estimate the prevalence of unrecognized cases with positive autoantibodies among type 2 diabetes (T2D) in a sample of the Bulgarian population and to compare some metabolic and inflammatory markers to those of patients having negative autoantibodies and subjects with latent autoimmune diabetes (LADA).

METHODS

Patients with T2D, patients with LADA, and control participants were enrolled. Antiglutamic acid decarboxylase, anti-insulinoma-associated 2, and antizinc transporter 8 autoantibodies were assayed through ELISA. C-reactive protein and interleukin 6 (IL-6) and tumor necrosis factor alpha were assessed.

RESULTS

Ten percent of patients with T2D had positive autoantibodies. They had lower body mass index (p = 0.014), worse glycemic control (HbA1c, p = 0.033), and better HDL cholesterol (p = 0.026) than those in negative autoantibodies cases. Compared to LADA, glycemia and anthropometric data did not differ significantly but metabolic syndrome was more prevalent among newly found cases with positive autoantibodies (p = 0.046). Their level of inflammatory markers was similar to that of patients having negative autoantibodies (p > 0.05), but IL-6 was higher when compared to LADA (p = 0.002).

CONCLUSION

Prevalence of patients having positive autoantibodies within T2D in the analyzed sample of the Bulgarian population was 10%. They shared common metabolic features with subjects with LADA, but inflammatory phenotype was closer to that of T2D.

LBP-4a improves insulin resistance via translocation and activation of GLUT4 in OLETF rats

Lycium barbarum polysaccharide (LBP) has been shown to ameliorate insulin resistance, but the identification of compounds from LBP and the mechanisms have not been clarified. In this study, LBP-4a was purified from Lycium barbarum by DEAE cellulose and Sephadex G-100 column chromatography, and the effects of LBP-4a on insulin resistance were investigated. The results indicated that LBP-4a caused translocation of the glucose transporter isoform 4 (GLUT4) to the cell surface, which in turn stimulated glucose uptake, and the effect was sensitive to wortmannin, an inhibitor of phosphoinositol 3-kinase (PI3-K), and SB203580, an inhibitor of p38 mitogen activated protein kinase (p38 MAPK (α, β)). Furthermore, the effects of LBP-4a on p38 MAPK activities were abrogated by pretreatment of rat adipocytes using SB203580. In summary, LBP-4a improved insulin resistance via translocation and activation of GLUT4 in OLETF rats, and the activation of PI3-K and p38 MAPK contributed to these effects.

Fatty fish consumption and risk of latent autoimmune diabetes in adults

Objective:

It has been suggested that intake of fatty fish may protect against both type 1 and type 2 diabetes. Hypotheses rest on the high marine omega-3 fatty acid eicosapentaenoic acid+docosahexaenoic acid (EPA+DHA) and vitamin D contents, with possible beneficial effects on immune function and glucose metabolism. Our aim was to investigate, for the first time, fatty fish consumption in relation to the risk of latent autoimmune diabetes in adults (LADA).

Methods:

Analyses were based on data from a Swedish case–control study with incident cases of LADA (n=89) and type 2 diabetes (n=462) and randomly selected diabetes-free controls (n=1007). Diabetes classification was based on the onset of age (⩾35), glutamic acid decarboxylase autoantibodies, and C-peptide. A validated food frequency questionnaire was used to derive information on previous intake of fish, polyunsaturated long-chain omega-3 fatty acids (n-3 PUFA) and supplementation of fish oil and vitamin D. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using logistic regression, adjusted for age, gender, body mass index (BMI), family history of diabetes, physical activity, smoking, education, and consumption of alcohol, fruit, vegetables and red meat.

Results:

Weekly fatty fish consumption (⩾1 vs <1 serving per week), was associated with a reduced risk of LADA but not type 2 diabetes (OR 0.51, 95% CI 0.30–0.87, and 1.01, 95% CI 0.74–1.39, respectively). Similar associations were seen for estimated intake of n-3 PUFA (⩾0.3 g per day; LADA: OR 0.60, 95% CI 0.35–1.03, type 2 diabetes: OR 1.14, 95% CI 0.79–1.58) and fish oil supplementation (LADA: OR 0.47, 95% CI 0.19–1.12, type 2 diabetes: OR 1.58, 95% CI 1.08–2.31).

Conclusions:

Our findings suggest that fatty fish consumption may reduce the risk of LADA, possibly through effects of marine-originated omega-3 fatty acids.

Similar weight-adjusted insulin secretion and insulin sensitivity in short-duration late autoimmune diabetes of adulthood (LADA) and type 2 diabetes: Action LADA 9 [corrected]

AIMS

To explore insulin sensitivity and insulin secretion in people with latent autoimmune diabetes in adulthood (LADA) compared with that in people with type 2 diabetes.

METHODS

A total of 12 people with LADA, defined as glutamic acid decarboxylase (GAD) antibody positivity and > 1 year of insulin independency (group A) were age-matched pairwise to people with type 2 diabetes (group B) and to six people with type 2 diabetes of similar age and BMI (group C). β-Cell function (first-phase insulin secretion and assessment of insulin pulsatility), insulin sensitivity (hyperinsulinemic-euglycemic clamp) and metabolic response during a mixed meal were studied.

RESULTS

Both first-phase insulin secretion and insulin release during the meal were greater (P = 0.05 and P = 0.009, respectively) in type 2 diabetes as compared with LADA; these differences were lost on adjustment for BMI (group C) and could be explained by BMI alone in a multivariate analysis. Neither insulin pulsatility, incretin secretion nor insulin sensitivity differed among the groups.

CONCLUSIONS

We found no evidence that LADA and type 2 diabetes were distinct disease entities beyond the differences explained by BMI.

Coffee consumption and the risk of latent autoimmune diabetes in adults--results from a Swedish case-control study

AIMS

Coffee consumption is associated with a reduced risk of Type 2 diabetes. Our aim was to investigate if coffee intake may also reduce the risk of latent autoimmune diabetes in adults, an autoimmune form of diabetes with features of Type 2 diabetes.

METHODS

We used data from a population-based case-control study with incident cases of adult onset (≥ 35 years) diabetes, including 245 cases of latent autoimmune diabetes in adults (glutamic acid decarboxylase antibody positive), 759 cases of Type 2 diabetes (glutamic acid decarboxylase antibody negative), together with 990 control subjects without diabetes, randomly selected from the population. Using questionnaire information on coffee consumption, we estimated the odds ratio of latent autoimmune diabetes in adults and Type 2 diabetes adjusted for age, sex, BMI, smoking, physical activity, alcohol, education and family history of diabetes.

RESULTS

Coffee intake was inversely associated with Type 2 diabetes (odds ratio 0.92, 95% CI 0.87-0.98 per cup/day). With regard to latent autoimmune diabetes in adults, the general trend was weak (odds ratio 1.04, 95% CI 0.96-1.13), but stratification by degree of autoimmunity (median glutamic acid decarboxylase antibody levels) suggested that coffee intake may be associated with an increased risk of high glutamic acid decarboxylase antibody latent autoimmune diabetes in adults (odds ratio 1.11, 95% CI 1.00-1.23 per cup/day). Furthermore, for every additional cup of coffee consumed per day, there was a 15.2% (P = 0.0268) increase in glutamic acid decarboxylase antibody levels.

CONCLUSIONS

Our findings confirm that coffee consumption is associated with a reduced risk of Type 2 diabetes. Interestingly, the findings suggest that coffee may be associated with development of autoimmunity and possibly an increased risk of more Type 1-like latent autoimmune diabetes in adults.

Latent autoimmune diabetes in adults in Asians: similarities and differences between East and West

Latent autoimmune diabetes in adults (LADA) is a form of autoimmune diabetes with features of both type 1 and type 2 diabetes and in the middle of the diabetes spectrum. Scientists clash on the question of whether this type of diabetes is a unique diabetes subtype. Multicenter studies have been performed in different countries, including the Korea National Diabetes Program (KNDP) collaboratory group, the Ehime study in Japan, the Not Insulin-Requiring Autoimmune Diabetes (NIRAD) study in Italy, the Nord-Trøndelag Health (HUNT) study in Norway, the UK Prospective Diabetes Study (UKPDS) in the UK, the Action LADA study in Europe and the LADA China study in China. These studies found universal immunogenetic effects associated with LADA, but with some ethnic differences. Herein we summarize those multicenter studies and compare the ethnic similarities and differences between East and West from epidemiological, clinical, immune, and genetic viewpoints.

Family history of Type 1 diabetes affects insulin secretion in patients with 'Type 2' diabetes

AIMS

The aim was to evaluate the impact of family history of diabetes on the phenotype of patients diagnosed with Type 2 diabetes and the frequency of susceptibility genotypes.

METHODS

Patients with Type 2 diabetes with family history for both Type 1 and Type 2 diabetes (FH(MIX, n) = 196) or Type 2 diabetes only (FH(T2), n = 139) matched for age, sex, BMI and age at diagnosis, underwent an oral glucose tolerance test and a combined glucagon test and insulin tolerance test. Glutamic acid decarboxylase (GAD) antibodies and major Type 1 and Type 2 diabetes susceptibility gene variants were analysed. Patients were stratified into groups according to family history or GAD antibody positivity (GADA+, GADA-) or a combination of these (GADA+/FH(MIX), GADA+/FH(T2), GADA-/FH(MIX), GADA-/FH(T2)).

RESULTS

Compared with other patients, those with FH(MIX) more often had GAD antibodies (14.3 vs. 4.3%, P = 0.003), and those with both FH(MIX) and GAD antibodies had the highest frequency of insulin deficiency (stimulated serum C-peptide < 0.7 nmol/l, GADA+/FH(MIX) 46.4% vs. GADA-/FH(MIX) 9.5% (P < 0.00001), GADA-/FH(T2) 4.5% (P < 0.00001), GADA+/FH(T2) 0%). Patients with GADA+/FH(MIX) more often had HLA-DQB1 risk genotypes compared with patients with GADA-/FH(MIX) or GADA-/FH(T2D) (47 vs. 23 or 14%, P = 0.05 and P < 0.00001, respectively). In logistic regression analyses, FH(MIX), GAD antibody positivity and HLA risk genotypes were independently associated with insulin deficiency.

CONCLUSION

A family history for both type 1 and type 2 diabetes was associated with higher prevalence of GAD antibodies and HLA-DQB1 risk genotypes than a family history of type 2 diabetes only, and was associated with earlier and more severe development of insulin deficiency, which was only partially explained by GAD antibodies and HLA.

Evaluation of insulin secretion and sensitivity in a patient with slowly progressive type 1 diabetes mellitus

We herein report the case of a patient with slowly progressive type 1 diabetes and insulin independence lasting for >10 years despite the detection of continuously elevated glutamic acid decarboxylase autoantibody titers. We monitored the patient's clinical course and analyzed his endogenous insulin secretion and sensitivity using an intravenous glucose tolerance test (IVGTT) and oral glucose tolerance test (OGTT). His body mass index remained at approximately 22, while his serum C-peptide immunoreactivity level gradually decreased. The level of insulin secretion was significantly higher on the OGTT than the IVGTT. The patient's insulin sensitivity was within the normal limits. These results suggest that maintaining a lifestyle sufficient to preserve insulin secretion and/or normal insulin sensitivity is important and that β-cell responsiveness to incretins may, in part, contribute to insulin independence.

Sleep disturbances and low psychological well-being are associated with an increased risk of autoimmune diabetes in adults. Results from the Nord-Trøndelag Health Study

AIMS

To investigate whether sleep disturbances and low psychological well-being are associated with an increased risk of autoimmune diabetes in adults (including LADA and type 1 diabetes) and type 2 diabetes.

METHODS

We used data from the Norwegian HUNT Study (n = 53,394) and estimated the risk of developing autoimmune diabetes in adults (n = 138) and type 2 diabetes (n = 1895) between 1984 and 2008 in relation to baseline self-reported psychological well-being and sleep problems.

RESULTS

Sleep disturbances and low psychological well-being were associated with an increased risk of autoimmune diabetes (hazard ratio 1.84, 95% confidence interval 1.10-3.09), primarily linked to poor sleep in men (1.83, 1.05-3.20) and low well-being in women (2.50, 1.03-6.54). Similar associations were seen with type 2 diabetes in relation to sleep problems (1.25, 1.08-1.44) in men and low well-being (1.34, 1.16-1.54), in both men and women. In autoimmune diabetes, these factors were associated with lower anti-GAD levels (177 vs. 306 WHO units/ml, p = 0.04).

CONCLUSIONS

Our findings indicate that psychosocial factors influence the risk of autoimmune diabetes in adults, possibly through mechanisms related to insulin resistance. This supports the notion that the aetiology of autoimmune diabetes with adult onset in some respects is similar to that of type 2 diabetes.

Latent autoimmune diabetes of adults is phenotypically similar to type 1 diabetes in a minority population

CONTEXT

Latent autoimmune diabetes of adults (LADA) is a form of autoimmune diabetes that has been classified as part of type 1 diabetes or as a distinct clinical entity. Its precise place as a disease category is therefore controversial.

OBJECTIVE

The objective of this study was to further examine this issue by comparing the phenotypes of LADA and type 1 diabetes in a predominately minority population.

PATIENTS AND METHODS

We studied 126 subjects who were anti-glutamic acid decarboxylase antibody-positive in two separate studies--63 subjects in an outpatient study (study 1), and 63 inpatients after resolution of ketoacidosis (study 2). Clinical and biochemical phenotyping was performed in all patients in each group.

RESULTS

Few significant differences were found in the clinical or biochemical phenotypes in patients classified as LADA when compared with type 1 diabetes. Adiposity, body mass index, waist/hip ratio, fasting plasma C-peptide, serum high-density lipoprotein cholesterol, and triglycerides were all similar. The only distinguishing feature was a history of hypertension (study 1) or systolic blood pressure (study 2). Also, a history of ketoacidosis did not influence the phenotype of LADA in the outpatients in any discernable way.

CONCLUSIONS

We conclude that LADA and type 1 diabetes are phenotypically indistinguishable in this predominantly minority population with a mean duration of glutamic acid decarboxylase antibody-positive diabetes of about 8 yr.

The evaluation and management of childhood type 2 diabetes mellitus

Diabetes in children is increasing in prevalence with obesity-associated insulin resistance being a major contributing factor. This report contains a comprehensive review of treatment paradigms regarding the management of diabetes in children. The information provided was collected from an extensive literature review on type 2 diabetes, and children and/or adolescents with diabetes and/or obesity treatment. There is a wide array of contributing factors to the development of diabetes and consequences that indicate the need to tailor treatment plans with reducing obesity as a primary outcome. Lipocentric treatment paradigms offer opportunity to reduce the impact of obesity.

High levels of education are associated with an increased risk of latent autoimmune diabetes in adults: results from the Nord-Trøndelag health study

OBJECTIVE

To investigate whether the risk for autoimmune diabetes in adults differs between socioeconomic groups and to compare such risk with that for type 2 diabetes.

RESEARCH DESIGN AND METHODS

The inhabitants of the Norwegian county of Nord-Trøndelag were investigated by questionnaires and clinical examinations on three occasions during 1984-2008. We used information from a subset consisting of 56,296 subjects (participating in at least two surveys), including 122 incident cases of autoimmune diabetes in adults (aged ≥35 and anti-GAD positive) and 1,555 cases of type 2 diabetes (aged ≥35 and anti-GAD negative). Hazard ratios (HRs) of diabetes associated with self-reported education and occupation were estimated by Cox proportional hazards models.

RESULTS

High levels of education (university versus primary school) were associated with an increased risk of autoimmune diabetes (HR 1.98 [95% CI 1.21-3.26]), after adjustment for BMI, lifestyle factors, and family history of diabetes. Case subjects with high levels of education had lower levels of C-peptide, tended to have higher levels of anti-GAD, and were more often treated with insulin. Conversely, these subjects had a reduced risk of type 2 diabetes (HR 0.69 [95% CI 0.57-0.82]), a risk that was partly explained by lower BMI and more physical activity (adjusted HR 0.89 [95% CI 0.74-1.06]).

CONCLUSIONS

High levels of education are associated with an increased risk of autoimmune diabetes in adults, a finding that may be mediated by effects on autoimmune activity. Because the association is not explained by traditional risk factors, other, currently unidentified, environmental factors are likely to be involved.

Is diabetes mellitus a continuous spectrum?

BACKGROUND

Diabetes mellitus has been historically divided into type 1 and type 2 diabetes, with type 1 being an autoimmune disease and type 2 being primarily a metabolic disease.

CONTENT

The current diabetes classification scheme needs to be reevaluated because of the accumulating evidence of immune system involvement in the pathophysiology of type 2 diabetes.

SUMMARY

There are similarities and differences between type 1 and type 2 diabetes with regard to pathogenesis, pathophysiology, and genetics. We propose a resolution to the dilemma of the current classification scheme.

Latent autoimmune diabetes in adults

CONTEXT

Autoantibodies that are reactive to islet antigens are present at the time of diagnosis in most patients with type 1 diabetes. Additionally, approximately 10% of phenotypic type 2 diabetic patients are positive for at least one of the islet autoantibodies, and this group is often referred to as "latent autoimmune diabetes in adults (LADA)." These patients share many genetic and immunological similarities with type 1 diabetes, suggesting that LADA, like type 1 diabetes, is an autoimmune disease. However, there are differences in autoantibody clustering, T cell reactivity, and genetic susceptibility and protection between type 1 diabetes and LADA, implying important differences in the underlying disease processes.

EVIDENCE ACQUISITION AND SYNTHESIS

In this clinical review, we will summarize the current understanding of LADA based on the MEDLINE search of all peer-reviewed publications (original articles and reviews) on this topic between 1974 and 2009.

CONCLUSIONS

In LADA, diabetes occurs earlier in the beta-cell-destructive process because of the greater insulin resistance. Complexities arise also because of variable definitions of LADA and type 1 diabetes in adults. As immunomodulatory therapies that slow or halt the type 1 diabetes disease process are discovered, testing these therapies in LADA will be essential.

No association of multiple type 2 diabetes loci with type 1 diabetes

AIMS/HYPOTHESIS

We used recently confirmed type 2 diabetes gene regions to investigate the genetic relationship between type 1 and type 2 diabetes, in an average of 7,606 type 1 diabetic individuals and 8,218 controls, providing >80% power to detect effects as small as an OR of 1.11 at a false-positive rate of 0.003.

METHODS

The single nucleotide polymorphisms (SNPs) with the most convincing evidence of association in 12 type 2 diabetes-associated gene regions, PPARG, CDKAL1, HNF1B, WFS1, SLC30A8, CDKN2A-CDKN2B, IGF2BP2, KCNJ11, TCF7L2, FTO, HHEX-IDE and THADA, were analysed in type 1 diabetes cases and controls. PPARG and HHEX-IDE were additionally tested for association in 3,851 type 1 diabetes families. Tests for interaction with HLA class II genotypes, autoantibody status, sex, and age-at-diagnosis of type 1 diabetes were performed with all 12 gene regions.

RESULTS

Only PPARG and HHEX-IDE showed any evidence of association with type 1 diabetes cases and controls (p = 0.004 and p = 0.003, respectively; p > 0.05 for other SNPs). The potential association of PPARG was supported by family analyses (p = 0.003; p (combined) = 1.0 x 10(-4)). No SNPs showed evidence of interaction with any covariate (p > 0.05).

CONCLUSIONS/INTERPRETATION

We found no convincing genetic link between type 1 and type 2 diabetes. An association of PPARG (rs1801282/Pro12Ala) could be consistent with its known function in inflammation. Hence, our results reinforce evidence suggesting that type 1 diabetes is a disease of the immune system, rather than being due to inherited defects in beta cell function or regeneration or insulin resistance.

Latent autoimmune diabetes of adulthood (LADA): an often misdiagnosed type of diabetes mellitus

PURPOSE

The purpose of this article is to raise awareness about a frequently misdiagnosed form of diabetes, latent autoimmune diabetes of adulthood (LADA), to describe its clinical and epidemiological characteristics, and to compare them to those of the more common and widely known types of diabetes, type 1 diabetes mellitus (DM) and type 2 DM.

DATA SOURCES

A review of the pertinent literature describing the features of LADA from 2000-2007 is summarized.

CONCLUSIONS

LADA is a rather common and often underrecognized form of diabetes whose clinical presentation falls somewhere between that of type 1 DM and type 2 DM. From a pathophysiological perspective, it is more closely related to type 1 DM, and some have even used the term type 1.5 diabetes to refer to it; however, it is most often misdiagnosed and treated as type 2 DM.

IMPLICATIONS FOR PRACTICE

Nurse practitioners (NPs) should always consider alternate diagnoses when patients with newly or previously identified adult-onset diabetes mellitus do not fit the traditional stereotype of type 2 DM (i.e., overweight with signs of insulin resistance and a significant family history of diabetes). Statistically, strong consideration must be given to the diagnosis of LADA, especially in those who are of normal weight, show little evidence of insulin resistance, and have hardly any family history of diabetes. Knowing the patient's exact diabetes type can give the NP a much greater understanding of the natural history of the patient's disease, the changes that may occur as the patient ages, and how to optimally manage their diabetes to minimize complications. Likewise, when a patient is correctly diagnosed, they can be empowered to manage their diabetes with the appropriate therapies.

Identifying latent autoimmune diabetes in adults in Korea: the role of C-peptide and metabolic syndrome

We aimed to establish the prevalence and characteristics of latent autoimmune diabetes in adults (LADA) and compare it with type 2 diabetes in 1370 Korean patients. The prevalence of LADA was 5.1%. Low C-peptide level and absence of metabolic syndrome were variables independently associated with the diagnosis of LADA.