Circulating anti-glutamic acid decarboxylase-65 antibody titers are positively associated with the capacity of insulin secretion in acute-onset type 1 diabetes with short duration in a Japanese population

Comparison of positive rates between glutamic acid decarboxylase antibodies and ElisaRSR™ 3 Screen ICA™ in recently obtained sera from patients who had been previously diagnosed with slowly progressive type 1 diabetes

AIMS/INTRODUCTION

This study aimed to compare the positivity rates of glutamic acid decarboxylase autoantibodies (GADA) and ElisaRSR™ 3 Screen ICA™ (3 Screen ICA), a newly developed assay for the simultaneous measurement of GADA, insulinoma-associated antigen-2 autoantibodies (IA-2A), and zinc transporter 8 autoantibodies (ZnT8A), in recently obtained sera from patients who had been previously diagnosed with slowly progressive type 1 diabetes (SPIDDM).

MATERIALS AND METHODS

We enrolled 53 patients with SPIDDM who were positive for GADA at the diagnosis and 98 non-diabetic individuals, and investigated the diagnostic accuracy of the 3 Screen ICA (cutoff index ≥30 units) compared with that of GADA. In addition, we compared the clinical characteristics of patients with SPIDDM who were negative or positive on 3 Screen ICA.

RESULTS

The positivity rates of 3 Screen ICA, GADA, IA-2A, and ZnT8A were 88.7, 86.8, 24.5, and 13.2%, respectively. The respective sensitivity, specificity, and positive and negative predictive values for SPIDDM were 88.7, 100, 100, and 94.2% by 3 Screen ICA and 86.8, 100, 100.0, and 93.3% by GADA. There were no significant differences in age at onset, duration of diabetes, body mass index, glycated hemoglobin and C-peptide levels, and the prevalence of autoimmune thyroiditis between patients with SPIDDM who were positive or negative on 3 Screen ICA. However, the prevalence of insulin users was significantly higher in those who were positive than in those who were negative on 3 Screen ICA.

CONCLUSIONS

Similar to GADA, 3 Screen ICA may be a useful diagnostic tool for detecting patients with SPIDDM.

Effects of rosuvastatin on serum glucose and insulin in hyperuricemic rats

Background

Hyperuricemia is a state in which the serum levels of uric acid (UA) are elevated. This study was to determine the roles of rosuvastatin in fasting blood glucose (FGB) and insulin levels in hyperuricemic rats.

Methods

Thirty-six Sprague-Dawley (SD) rats were randomized divided into the control, model and rosuvastatin groups: the control was given no intervention, the model group was established by administrating yeast extract powder and oxonic acid potassium salt, and the rosuvastatin group was given intravenous administration of rosuvastatin for 28 days in hyperuricemic rats. Serum uric acid (SUA), fasting blood glucose (FBG), fasting blood insulin (FBI), glutamic acid decarboxylase antibody (GADA), oral glucose tolerance test (OGTT) levels, and the ultrastructure of pancreatic β-cells were measured. Also, homeostasis model assessment of insulin resistance (HOMA-IR) scores was computed in three groups.

Results

Compared to the model group, SUA were decreased, while the FBG, GADA, OGTT and HOMA-IR at week 4 were significantly increased in rosuvastatin group. However, FBI was not significantly changed between three groups. It was also showed that the structure of pancreatic β-cells was damaged and the number of β-cells was changed in hyperuricemic rats while they were aggravated in rosuvastatin group.

Conclusion

Rosuvastatin has roles in inducing FGB, GADA, OGTT and pancreatic β-cells damage in hyperuricemic rats.

Chemokines in Type 1 Diabetes Mellitus

Background

Previous studies suggested that chemokines may play an important role in the formation and mediation of immune microenvironments of patients affected by Type 1 Diabetes Mellitus (T1DM). The aim of this study was to summarise available evidence on the associations of different chemokines with T1DM.

Methods

Following PRISMA guidelines, we systematically searched in PubMed, Web of Science, Embase and Cochrane Library databases for studies on the associations of different chemokines with T1DM. The effect size of the associations were the standardized mean differences (SMDs) with corresponding 95% confidence intervals (CIs) of the chemokines concentrations, calculated as group differences between the T1DM patients and the controls. These were summarized using network meta-analysis, which was also used to rank the chemokines by surface under cumulative ranking curve (SUCRA) probabilities.

Results

A total of 32 original studies on the association of different chemokines with T1DM were identified. Fifteen different chemokine nodes were compared between 15,683 T1DM patients and 15,128 controls, and 6 different chemokine receptor nodes were compared between 463 T1DM patients and 460 controls. Circulating samples (blood, serum, and plasma) showed that concentrations of CCL5 and CXCL1 were significantly higher in the T1DM patients than in the controls (SMD of 3.13 and 1.50, respectively). On the other hand, no significant difference in chemokine receptors between T1DM and controls was observed. SUCRA probabilities showed that circulating CCL5 had the highest rank in T1DM among all the chemokines investigated.

Conclusion

The results suggest that circulating CCL5 and CXCL1 may be promising novel biomarkers of T1DM. Future research should attempt to replicate these findings in longitudinal studies and explore potential mechanisms underlying this association.

Lack of effect of Lactobacillus rhamnosus GG and Bifidobacterium lactis Bb12 on beta-cell function in children with newly diagnosed type 1 diabetes: a randomised controlled trial

INTRODUCTION

The gut microbiota may be relevant in the development of type 1 diabetes (T1D). We examined the effects of Lactobacillus rhamnosus GG and Bifidobacterium lactis Bb12 on beta-cell function in children with newly diagnosed T1D.

RESEARCH DESIGN AND METHODS

Children aged 8-17 years with newly (within 60 days) diagnosed T1D were enrolled in a double-blind, randomised controlled trial in which they received L. rhamnosus GG and B. lactis Bb12 at a dose of 10⁹ colony-forming units or placebo, orally, once daily, for 6 months. The follow-up was for 12 months. The primary outcome measure was the area under the curve (AUC) of the C-peptide level during 2-hour responses to a mixed meal.

RESULTS

Ninety-six children were randomised (probiotics, n=48; placebo n=48; median age 12.3 years). Eighty-eight (92%) completed the 6-month intervention, and 87 (91%) completed the follow-up at 12 months. There was no significant difference between the study groups for the AUC of the C-peptide level. For the secondary outcomes at 6 months, there were no differences between the study groups. At 12 months, with one exception, there also were no significant differences between the groups. Compared with the placebo group, there was a significantly increased number of subjects with thyroid autoimmunity in the probiotic group. However, at baseline, there was also a higher frequency of thyroid autoimmunity in the probiotic group. There were no cases of severe hypoglycemia or ketoacidosis in any of the groups. No adverse events related to the study products were reported.

CONCLUSIONS

L. rhamnosus GG and B. lactis Bb12, as administered in this study, had no significant effect in maintaining the residual pancreatic beta-cell function in children with newly diagnosed T1D. It remains unclear which probiotics, if any, alone or in combination, are potentially the most useful for management of T1D.

TRIAL REGISTRATION NUMBER

NCT03032354.

Circulating anti-glutamic acid decarboxylase-65 antibody titers are positively associated with the capacity of insulin secretion in acute-onset type 1 diabetes with short duration in a Japanese population

Aims/Introduction

To elucidate the relationship between titers of islet autoantibodies, the C‐X‐C motif chemokine 10 – a circulating chemokine that activates T‐helper 1 cells leading to β‐cell destruction – and β‐cell function in type 1 diabetes.

Materials and Methods

In total, 58 type 1 diabetes patients positive for glutamic decarboxylase‐65 autoantibodies (GADA)‐radioimmunoassay (mean age 54.1 years; 27 acute‐onset cases and 31 slowly progressive cases) were enrolled; serum C‐X‐C motif chemokine 10 (n = 50), zinc transporter 8 autoantibodies (n = 50) and GADA (n = 58) by an enzyme‐linked immunosorbent assay, and insulinoma‐associated antigen‐2 autoantibodies by radioimmunoassay (n = 50) were measured. The ratio of 100 × random C‐peptide (ng/mL)‐to‐plasma glucose levels (mg/dL; C‐peptide index [CPI]) was measured.

Results

The CPI significantly decreased in both groups with the progression of disease duration. GADA titers by radioimmunoassay and enzyme‐linked immunosorbent assay were strongly correlated with the CPI in acute‐onset type 1 diabetes patients with a shorter disease duration (≤10 years), but not in those with a longer duration or slowly progressive type 1 diabetes. Neither insulinoma‐associated antigen‐2 nor zinc transporter 8 autoantibodies titers were correlated with the CPI. Serum C‐X‐C motif chemokine 10 levels in both groups were significantly higher than in non‐diabetic controls, and persisted at high levels even in those with chronic duration.

Conclusions

Among islet autoantibodies, the intensity of the humoral immune response, as defined by GADA titers, reflected the degree of residual β‐cell function in acute‐onset type 1 diabetes patients with short duration. Prolonged disease activity might accelerate β‐cell impairment in both subtypes of type 1 diabetes.