ELISA Test for Analyzing of Incidence of Type 1 Diabetes Autoantibodies (GAD and IA2) in Children and Adolescents

Targeting GABA signaling in type 1 diabetes and its complications- an update on the state of the art

Type 1 diabetes (T1D) is an autoimmune disease that leads to the progressive destruction of insulin-producing β cells, resulting in lifelong insulin dependence and a range of severe complications. Beyond conventional glycemic control, innovative therapeutic strategies are needed to address the underlying disease mechanisms. Recent research has highlighted gamma-aminobutyric acid (GABA) as a promising therapeutic target for T1D due to its dual role in modulating both β cell survival and immune response within pancreatic islets. GABA signaling supports β cell regeneration, inhibits α cell hyperactivity, and promotes α-to-β cell transdifferentiation, contributing to improved islet function. Moreover, GABA's influence extends to mitigating T1D complications, including nephropathy, neuropathy, and retinopathy, as well as regulating central nervous system pathways involved in glucose metabolism. This review consolidates the latest advances in GABA-related T1D therapies, covering animal preclinical and human clinical studies and examining the therapeutic potential of GABA receptor modulation, combination therapies, and dietary interventions. Emphasis is placed on the translational potential of GABA-based approaches to enhance β cell viability and counteract autoimmune processes in T1D. Our findings underscore the therapeutic promise of GABA signaling modulation as a novel approach for T1D treatment and encourage further investigation into this pathway's role in comprehensive diabetes management.

Spectrum of neurological manifestations, existence of diabetes mellitus, and 5-year mortality and cancer association outcomes in a cohort of Omani patients with positive anti- GAD autoimmunity

OBJECTIVES

There is scarce data in the literature concerning the anti-GAD65 antibodies (GAD-Abs) autoimmunity in the Omani population.

METHODS

Retrospective cohort study included GAD-Abs positive patients (n = 444) presented to a tertiary referral center in Oman from January 2005 until January 2018, with a five-year follow-up to study the cancer association and mortality outcomes.

RESULTS

Out of 444 patients, 27 patients (6.1%) showed GAD-Abs related neurological disorders. Adult age group was significantly associated with more GAD-Abs related neurological manifestations compared to pediatric and adolescents age group (p = 0.045). There was no association between the presence or absence of neurological manifestations with diabetes mellitus nor the titer level of GAD-Abs. Refractory status epilepticus and stiff person syndrome were the main causes of death in patients with neurological manifestations over five years and none of them found to have associated cancer.

CONCLUSION

The GAD-Abs autoimmunity represents a spectrum of neurological manifestations with variable severity and outcome among Omanis with positive GAD-Abs testing. The results of this study will serve as a platform for future studies to address the impact of GAD-Abs autoimmunity on the morbidity, mortality and treatment efficacy in the Omani population.

Pregnancy and diabetic ketoacidosis: fetal jeopardy and windows of opportunity

Background

Diabetic ketoacidosis (DKA) during pregnancy poses significant risks to both the mother and fetus, with an increased risk of fetal demise. Although more prevalent in women with Type I diabetes (T1D); those with Type 2 diabetes (T2D) and gestational diabetes mellitus (GDM) can also develop DKA. A lack of information about DKA during pregnancy exists worldwide, including in South Africa.

Objective

This study examined the characteristics and outcomes associated with DKA during pregnancy.

Methods

The study took place between 1 April 2020 and 1 October 2022. Pregnant women with DKA, admitted to Tygerberg Hospital's Obstetric Critical Care Unit (OCCU) were included. Maternal characteristics, precipitants of DKA, adverse events during treatment, and maternal-fetal outcomes were examined.

Results

There were 54 episodes of DKA among 47 women. Most DKA's were mild and occurred in the third trimester. Pregestational diabetes dominated (31/47; 60%), with 47% having T1D and 94% requiring insulin. Seven women (7/47, 15%; T2D:6, T1D:1) had two episodes of DKA during the same pregnancy. Most women (32/47; 68%) were either overweight or obese. Yet, despite the T2D phenotype, biomarkers indicated that auto-immune diabetes was prevalent among women without any prior history of T1D (6/21; 29%). Twelve women (26%) developed gestational hypertension during pregnancy, and 17 (36%) pre-eclampsia. Precipitating causes of DKA included infection (14/54; 26%), insulin disruption (14/54; 26%) and betamethasone administration (10/54; 19%). More than half of the episodes of DKA involved hypokalemia (35/54, 65%) that was associated with fetal death (P=0.042) and hypoglycemia (28/54, 52%). Preterm birth (<37 weeks' gestation) occurred in 85% of women. No maternal deaths were recorded. A high fetal mortality rate (13/47; 28%) that included 11 spontaneous intrauterine deaths and two medical terminations, was observed.

Conclusion

Women with DKA have a high risk of fetal mortality as well as undiagnosed auto-immune diabetes. There is a strong link between maternal hypokalemia and fetal loss, suggesting an opportunity to address management gaps in pregnant women with DKA.

Clinical features, epidemiology, autoantibody status, HLA haplotypes and genetic mechanisms of type 1 diabetes mellitus among children in Qatar

To describe the clinical features, epidemiology, autoantibody status, HLA haplotypes and genetic mechanisms of type 1 diabetes mellitus (T1DM). Patients (0-18 years) with diabetes were recruited. Clinical data was collected, autoantibodies and c-peptide were measured. Whole Genome Sequencing was performed. Genomic data analysis was compared with the known genes linked with T1DM and HLA alleles were studied. 1096 patients had one or more antibody positivity. The incidence of T1DM in 2020 was 38.05 per 100,000 children and prevalence was 249.73. GADA was the most common autoantibody followed by IAA. Variants in GSTCD, SKAP2, SLC9B1, BANK1 were most prevalent. An association of HLA haplotypes DQA1*03:01:01G (OR = 2.46, p value = 0.011) and DQB1*03:02:01G (OR = 2.43, p value = 0.022) was identified. The incidence of T1DM in Qatar is the fourth highest in the world, IA2 autoantibody was the most specific with some patients only having ZnT8 or IA2 autoantibodies thus underlining the necessity of profiling all 4 autoantibodies. The genes associated with T1DM in the Arab population were different from those that are common in the Caucasian population. HLA-DQ was enriched in the Qatari patients suggesting that it can be considered a major risk factor at an early age.

Saudi children with celiac disease: are they at risk of developing type-1 diabetes mellitus?

Objectives Patients with type-1 diabetes mellitus (T1DM) and celiac disease (CeD) share the same genetic susceptibility alleles. The diabetes-associated autoantibodies (DAA) may be detected in CeD patients. The aim of this study is to describe the prevalence of DAA in children with CeD. Methods This is a cross-sectional study of children with CeD. The CeD patients were divided into two groups; group 1 (n=23) included patients with isolated CeD and group 2 included patients with combined T1DM and CeD. The study was conducted at King Abdulaziz University Hospital (KAUH) in 2012-2014. DAA, including glutamic acid decarboxylase antibodies (GADA) and protein tyrosine phosphatase-2 antibodies (IA-2), were measured by enzyme-linked immunosorbent assay (ELISA) in both groups. Clinical, demographic, and laboratory data were collected from the patients' medical charts. Results DAA were determined in 23 patients in group-1 and 18 patients in group-2. Group-1 comprised 43.5% males and 56.5% females; the mean age was 15 ± 3.7 years (with a range of 5-18 years). The prevalence of GADA and IA-2 was 69.6 and 4%, respectively. Group-2 comprised 55.6% males and 44.4% females; the mean age was 15.1 ± 2.8 years (with a range of 7-18 years). The prevalence of GADA and IA-2 was 66.7 and 22.2%, respectively. No significant differences were found between both groups in the prevalence of GADA (p=1.0) or IA-2 (p=0.15). Conclusions Saudi children with CeD have higher prevalence of GADA than reported in a number of other Western studies. Long-term follow-up data is required before recommending routine screening for DAA.

[Effects of glycosylated hemoglobin and disease course on islet β-cell function in patients with type 2 diabetes]

OBJECTIVE

To compare islet β-cell function in type 2 diabetic (T2DM) patients with different glycosylated hemoglobin (HbA1c) levels and diabetes durations.

METHODS

We examined body parameters, biochemical profiles and islet autoantibodies in a total of 803 T2DM patients admitted in the Department of Endocrinology of the First Affiliated Hospital of Nanjing Medical University between December, 2014 and April, 2016. The patients were stratified by HbA1c level and disease course and underwent steamed bun test to evaluate islet β-cell function and insulin resistance.

RESULTS

Linear correlation analysis showed that in T2DM patients, HbA1c level was negatively correlated with HOMA2-IR, HOMA2-%β, DI30 and DI180 (P=0.000), and disease course was negatively correlated with HOMA2-IR, HOMA2-% β, and DI180 (P &lt; 0.05). The patients with different HbA1c levels showed significantly different HOMA2-IR, HOMA2-%β, DI30 and DI180 (P=0.000); HOMA2-%β, DI30 and DI180 were significantly higher in patients with HbA1c levels &lt; 7.8%, and HOMA2-% β was significantly decreased in patients with HbA1c levels above 9.8%. The patients with different disease courses also had significant differences in HOMA2-IR, HOMA2-%β, DI30, and DI180 (P=0.000), and as the disease course extended, DI30 and DI180 tended to decrease progressively. Multivariate linear regression analysis showed that HbA1c, diabetes duration, and body mass index (BMI) were all independent factors affecting islet β- cell function in T2DM patients.

CONCLUSIONS

The secretion function of islet β cells decreases progressively with the increase of HbA1c level or disease course in T2DM patients, but the disease course does not appear to have an effect as strong as that of HbA1c level on islet β cell function.

Proteoliposome-based full-length ZnT8 self-antigen for type 1 diabetes diagnosis on a plasmonic platform

Identified as a major biomarker for type 1 diabetes (T1D) diagnosis, zinc transporter 8 autoantibody (ZnT8A) has shown promise for staging disease risk and disease diagnosis. However, existing assays for ZnT8 autoantibody (ZnT8A) are limited to detection by soluble domains of ZnT8, owing to difficulties in maintaining proper folding of a full-length ZnT8 protein outside its native membrane environment. Through a combined bioengineering and nanotechnology approach, we have developed a proteoliposome-based full-length ZnT8 self-antigen (full-length ZnT8 proteoliposomes; PLR-ZnT8) for efficient detection of ZnT8A on a plasmonic gold chip (pGOLD). The protective lipid matrix of proteoliposomes improved the proper folding and structural stability of full-length ZnT8, helping PLR-ZnT8 immobilized on pGOLD (PLR-ZnT8/pGOLD) achieve high-affinity capture of ZnT8A from T1D sera. Our PLR-ZnT8/pGOLD exhibited efficient ZnT8A detection for T1D diagnosis with ∼76% sensitivity and ∼97% specificity (n = 307), superior to assays based on detergent-solubilized full-length ZnT8 and the C-terminal domain of ZnT8. Multiplexed assays using pGOLD were also developed for simultaneous detection of ZnT8A, islet antigen 2 autoantibody, and glutamic acid decarboxylase autoantibody for diagnosing T1D.

A case of a novel mutation in HNF1β-related maturity-onset diabetes of the young type 5 with diabetic kidney disease complication in a Chinese family

AIMS

Precise diagnosis of maturity-onset diabetes of the young (MODY) has proven valuable for understanding mechanism of diabetes and selecting optimal therapy. A proband and her mother with diabetic kidney disease (DKD) were studied to investigate potential genes responsible for diabetes and different severity of DKD between the parent and offspring.

METHODS

The family with suspected MODY underwent mutational analyses by the whole exome sequencing (WES). Candidate pathogenic variants were validated by Sanger sequencing and tested for co-segregation. The clinical parameters of subjects were collected from medical records.

RESULTS

A novel missense heterozygous mutation in exon 4 of the hepatocyte nuclear factor 1β (HNF1β), c.1007A > G (p.H336R), was identified in both the proband and her mother. Moreover, comparing the family's WES results, we found that the proband had acquired a KCNQ1 gene mutation from her father and acquired ACE and SORBS1 gene mutations from her mother. These three genes are known susceptibility genes of DKD and may impose additional effects contributing to DKD severity.

CONCLUSIONS

A novel mutation in HNF1β-MODY was identified in a Chinese family complicated with DKD, and the additional effect of pathogenic variants in susceptibility genes was speculated to contribute to DKD severity.