Prospective prediction of spontaneous but not recurrent autoimmune diabetes in the non-obese diabetic mouse

Aims/hypothesis Type 1 diabetes is a T cell-mediated autoimmune disease with a clinically silent prodrome, during which prediction and treatment of disease are theoretically possible. Using retrospective analysis, spontaneous disease in the non-obese diabetic (NOD) mouse has been correlated with islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP)-reactive CD8⁺ T cells in the peripheral blood. In this study, we determined prospectively whether IGRP-reactive T cells in peripheral blood could predict disease occurrence. Since recurrent autoimmunity is an important contributor to transplant failure, we also determined whether failure of islet grafts (syngeneic and allogeneic) could be predicted by the presence of circulating autoreactive T cells. Materials and methods Peripheral blood samples were taken weekly from female NOD mice between the ages of 8 and 30 weeks and from NOD mice transplanted with NODscid islets. Peripheral blood cells and islet grafts were analysed for the presence of IGRP-reactive CD8⁺ T cells by flow cytometry. Results Prospective analysis of peripheral blood IGRP-reactive T cells in the prediabetic period predicted disease development with a sensitivity of 100% and a specificity of 60%, resulting in positive and negative predictive values of 85 and 100%, respectively. Significant proportions of IGRP-reactive T cells were found in the grafts, but not in peripheral blood of NOD mice undergoing syngeneic and allogeneic rejection. Conclusions/interpretation The occurrence of spontaneous diabetes can be predicted prospectively by measuring peripheral blood autoreactive T cells. Rejection of syngeneic or allogeneic islets is associated with large populations of autoreactive CD8⁺ T cells within islets, suggesting that immunodominant autoreactive T cells during the prediabetic period are also responsible for autoimmune graft rejection.     

Allogeneic islet transplantation with monitoring of islet‐specific cellular autoimmunity in a Japanese patient with type 1 diabetes: A case report

Here, we report a case of allogeneic islet transplantation in Japan. A 48‐year‐old man received intraportal islet transplantation (5,945 islet equivalent/kg), and stabilization of blood glucose levels and suppression of hypoglycemia were achieved. In the present case, we used our original assessment method to detect the responses of the recipient’s T cells to islet autoantigens over time to monitor cellular autoimmunity. Other markers could not predict graft dysfunction in advance, but our method detected the activation of islet antigen‐specific CD8⁺ T‐cell responses before the deterioration of pancreatic β‐cell function, indicating the possibility of the non‐invasive detection of pancreatic β‐cell damage due to recurrent autoimmunity.     

Pancreatic beta cell function persists in many patients with chronic type 1 diabetes, but is not dramatically improved by prolonged immunosuppression and euglycaemia from a beta cell allograft

Aims/hypothesis  We measured serum C-peptide (at least 0.167 nmol/l) in 54 of 141 (38%) patients with chronic type 1 diabetes and sought factors that might differentiate those with detectable C-peptide from those without it. Finding no differences, and in view of the persistent anti-beta cell autoimmunity in such patients, we speculated that the immunosuppression (to weaken autoimmune attack) and euglycaemia accompanying transplant-based treatments of type 1 diabetes might promote recovery of native pancreatic beta cell function. Methods  We performed arginine stimulation tests in three islet transplant and four whole-pancreas transplant recipients, and measured stimulated C-peptide in select venous sampling sites. On the basis of each sampling site’s C-peptide concentration and kinetics, we differentiated insulin secreted from the individual’s native pancreatic beta cells and that secreted from allografted beta cells. Results  Selective venous sampling demonstrated that despite long-standing type 1 diabetes, all seven beta cell allograft recipients displayed evidence that their native pancreas secreted C-peptide. Yet even if chronic immunosuppression coupled with near normal glycaemia did improve native pancreatic C-peptide production, the magnitude of the effect was quite small. Conclusions/interpretation  Some native pancreatic beta cell function persists even years after disease onset in most type 1 diabetic patients. However, if prolonged euglycaemia plus anti-rejection immunosuppressive therapy improves native pancreatic insulin production, the effect in our participants was small. We may have underestimated pancreatic regenerative capacity by studying only a limited number of participants or by creating conditions (e.g. high circulating insulin concentrations or immunosuppressive agents toxic to beta cells) that impair beta cell function. Trial registration  ClinicalTrials.gov NCT00246844 and NCT00006505. E. H. Liu, B. J. Digon III and B. Hirshberg contributed equally to this study.     

Pentoxifylline at clinically achievable levels inhibits FMLP-induced neutrophil responses,but not priming,upregulation of cell-adhesion molecules,or migration induced by GM-CSF

Abstract: Pentoxifylline (PTX) administered after bone-marrow transplantation reduces procedure-related organ damage mediated by TNFα. GM-CSF is also given post-transplant to stimulate earlier neutrophil recovery. Because PTX has been shown to inhibit neutrophil function, we sought to determine whether it also inhibited the effects of GM-CSF on neutrophil activity. The study confirmed that PTX at clinically achievable concentration (5–10 μmol/l) attenuated the responses of human neutrophils to chemotactic peptide, whereas it did not inhibit the effect of GM-CSF on neutrophil function even at high concentrations. In experiments with human neutrophils, neither the direct effects of GM-CSF such as stimulation of migration and increased expression of CD11b, nor the priming effects of GM-CSF on the respiratory burst, were inhibited by PTX. In experiments with monkeys, intravenous administration of PTX did not block subsequent GM-CSF-induced neutrophil CD11b upregulation or phagocyte margination, even when near millimolar plasma levels of pentoxifylline were obtained. The retention of cytokine-stimulated activities suggests that PTX will not compromise the response of neutrophils to stimuli from infectious foci.     

Juvenile case with the coexistence of maturity‐onset diabetes of the young 1 and later‐onset latent autoimmune diabetes in youth

We present the case of a 12‐year‐old Japanese girl, who was positive for markers of both maturity‐onset diabetes of the young and latent autoimmune diabetes in youth. She was initially diagnosed with maturity‐onset diabetes of the young 1 based on the molecular analysis, and she later developed an autoimmune response, leading to β‐cell‐associated antibody‐positive diabetes. She was treated with incretin‐associated drugs and maintained adequate glycemic control. Pathophysiologically, there was an overlap between the two different types of diabetes, because the hyperglycemia and β‐cell stress seen in non‐autoimmune diabetes can cause β‐cell autoimmunity over time.     

Dual onset of type 1 diabetes mellitus and Graves’ disease during treatment with pegylated interferon α-2b and ribavirin for chronic hepatitis C

Currently, a combination therapy of pegylated (PEG) interferon (IFN) α-2b and ribavirin are being widely used for the treatment of chronic hepatitis C (CHC). We describe here a case of dual onset of type 1 DM accompanied by ketoacidosis, and Graves’ disease during the combination therapy via the autoimmune process.     

Antioxidants and coronary artery disease among individuals with type 1 diabetes: Findings from the Pittsburgh Epidemiology of Diabetes Complications Study

OBJECTIVE: Oxidative stress has been implicated in the development of diabetes and cardiovascular disease. We evaluated the effect of serum antioxidants and total antioxidant reserve (TAR) on coronary artery disease (CAD) incidence in type 1 diabetes. METHODS: Subjects were identified from the Pittsburgh Epidemiology of Diabetes Complications Study (EDC) cohort, a 10-year prospective study of childhood-onset type 1 diabetes. Mean age at baseline was 28 and diabetes duration 19 years. Coronary artery disease was defined as physician-diagnosed angina, confirmed MI, stenosis >or=50%, ischemic electrocardiogram (ECG), or revascularization. Controls were gender, age, and diabetes duration (+/-3 years) matched with cases. Samples and risk factors used in analyses were identified from the earliest exam prior to incidence in cases (54 cases, 67 controls). RESULTS: None of the antioxidant measures (alpha-tocopherol, gamma-tocopherol, retinol, TAR) showed protection against incident CAD overall. However, a protective effect of alpha-tocopherol against CAD was observed among antioxidant supplement users (HR=0.22, 95% CI=0.10-0.49) and in renal disease (HR=0.46, 95% CI=0.23-0.91). Despite similar alpha-tocopherol concentration, there was no protective effect among nonusers of antioxidant supplements. CONCLUSIONS: High alpha-tocopherol levels among patients with renal disease and in those using vitamin supplements were associated with lower CAD risk in type 1 diabetes. The specificity of these effects merits further investigation.     

Therapeutic approaches for latent autoimmune diabetes in adults: One size does not fit all

Recent advances in the understanding of latent autoimmune diabetes in adults (LADA) pathophysiology make it increasingly evident that people with LADA comprise a heterogenous group of patients. This makes the establishment of a standard treatment algorithm challenging. On top of its glucose‐lowering action, insulin may exert anti‐inflammatory effects, rendering it an attractive therapeutic choice for a type of diabetes in which autoinflammation and beta cell insufficiency play major pathogenetic roles. However, there is growing evidence that other antidiabetic drugs, such as metformin, dipeptidyl peptidase‐4 inhibitors, glucagon‐like peptide‐1 receptor agonists, and thiazolidinediones, might have a role in optimizing glycemic control and preserving beta cell function in individuals with LADA, either alone or in combination with insulin. Although most of these drugs have been routinely used in the daily clinical setting for years, large prospective randomized trials are needed to assess whether they are capable of delaying progression to insulin dependence as well as their effects on diabetic complications. The aim of the present review is to discuss the current state and future perspectives of LADA therapy, emphasizing the need for individualized and patient‐centered therapeutic approaches.     

High incidence of type 1 diabetes mellitus during or shortly after treatment with pegylated interferon α for chronic hepatitis C virus infection

Background: Development of diabetes mellitus (DM) during or shortly after treatment with interferon α (IFN‐α) in patients with chronic hepatitis C virus (HCV) infection has been reported sporadically. We prospectively screened for DM during and after IFN‐α therapy for chronic HCV infection. Methods: Blood glucose levels of patients with chronic HCV infection were routinely assessed at all outpatient visits during and after treatment with pegylated‐IFN‐α (Peg‐IFN‐α) and ribavirin (Riba). Results: Between December 2002 and October 2005, 189 non‐diabetic patients were treated with Peg‐IFN‐α/Riba, of whom five developed type 1 DM (2.6%), three type 2 DM (1.6%) and one an indeterminate type of DM. Classical symptoms of DM were present in three patients who developed DM shortly after cessation of Peg‐IFN‐α/Riba. In the other patients, symptoms of DM were either indistinguishable from side effects caused by Peg‐IFN‐α/Riba or absent. Conclusion: Our study showed a high incidence of type 1 DM during Peg‐IFN‐α/Riba therapy for chronic HCV infection. Symptoms of DM may be absent or mistaken for Peg‐IFN‐α/Riba‐associated side effects. To diagnose DM without delay, we propose routine assessment of blood glucose at all outpatient visits during and after Peg‐IFN‐α/Riba treatment in chronic HCV patients.     

No deterioration in insulin sensitivity,but impairment of both pancreatic β-cell function and glucose sensitivity,in Japanese women with former gestational diabetes mellitus

To identify the primary pathogenic factors involved in the development of Type 2 diabetes mellitus (DM), we studied Japanese women with former gestational diabetes mellitus (GDM) who are at risk for the later development of Type 2 DM. We used the minimal model analysis derived from frequently sampled intravenous glucose tolerance test (FSIGT). The subjects consisted of eight non-obese women with a history of GDM and eight non-obese normal women as control subjects. The 75 g oral glucose tolerance test (75 g OGTT) performed within 6 months of delivery confirmed that all the subjects with former GDM had a normal glucose tolerance. Insulin sensitivity (SI) derived from the minimal model analysis was not different between the two groups. Glucose effectiveness at zero insulin (GEZI), reflecting tissue glucose sensitivity, was significantly lower in former GDM patients than in control subjects (1.18 ± 0.34 vs 2.26 ± 0.29 × 10⁻² min⁻¹, p < 0.05). The early phase insulin secretion found in FSIGT was markedly reduced to 56 % of that observed in control subjects (1250 ± 187.4 vs 2223 ± 304.3 pmol l⁻¹ min, p < 0.01). Our results indicate that in former GDM patients, who are Japanese and non-obese, impairment of the acute insulin response to glucose and a decrease in tissue glucose sensitivity rather than insulin sensitivity are the primary pathogenic factors involved. Copyright © 1998 John Wiley & Sons, Ltd.     

Comparison of three α‐glucosidase inhibitors for glycemic control and bodyweight reduction in Japanese patients with obese type 2 diabetes

Aims/Introduction

α‐Glucosidase inhibitors (αGIs) are widely used for the primary treatment of type 2 diabetes. We compared the clinical effects of three αGIs (miglitol, acarbose and voglibose) in patients with obese type 2 diabetes.

Materials and Methods

Japanese patients (n = 81) with obese type 2 diabetes (body mass index [BMI] ≥25 kg/m²) were enrolled in this multicenter, open‐label study. The participants were randomized into the miglitol (n = 18), acarbose (n = 22), voglibose (n = 19) or control (n = 22) groups. Glycemic control (fasting blood glucose and glycated hemoglobin [HbA1c]), bodyweight, BMI, serum insulin, serum lipids (low‐density lipoprotein and high‐density lipoprotein cholesterol, and triacylglycerols) and adipocytokines (leptin and adiponectin) were evaluated every 4 weeks for 12 weeks.

Results

In the miglitol group, HbA1c was improved significantly from the baseline at all points. The changes in HbA1c at 8 and 12 weeks from baseline were greater in the miglitol group than the control group. The voglibose group showed significant improvements in HbA1c at 12 weeks. Bodyweight and BMI were decreased significantly in the miglitol group. In addition, significant correlations were observed between the decrements in HbA1c and bodyweights over 12 weeks in the miglitol (r = 0.759, P < 0.001) and voglibose groups (r = 0.667, P = 0.002). Serum lipid and adipocytokine levels were not altered in any groups.

Conclusions

αGIs, especially miglitol, can effectively control blood glucose and bodyweight in obese type 2 diabetes. This study was registered with UMIN (no. UMIN000006465).