Nephropathy in type 1 diabetes is diminished in carriers of HLA-DRB1*04: the genetics of kidneys in diabetes (GoKinD) study

Exploring potential correlations between HLA class II and the risk of microvascular complications in Japanese patients with type 1 diabetes

Managing complications in Type 1 diabetes (T1D) remains challenging. HLA genes, particularly DR and DQ, are linked to T1D susceptibility. We studied 48 Japanese T1D inpatients and revealed associations between DRB1*04:05-DQB1*04:01 and DRB1*09:01-DQB1*03:03 haplotypes and complications, offering a new perspective for future research.

Unraveling chronic kidney disease in children: a surprising manifestation of celiac disease

Celiac disease, firstly described in children, is a type of T-cell enteropathy that occurs in individuals genetically predisposed to gluten exposure. The estimated global prevalence of celiac disease is continuously increasing. Although, traditionally, celiac disease was diagnosed in children with failure to thrive and digestive issues, it is now recognized that may present with a wide range of symptoms beyond gastrointestinal ones. Celiac disease continues to pose significant challenges due to the continuous advancement of knowledge in understanding its pathophysiology, diagnosing the condition, managing its effects, and exploring potential therapeutic approaches. The prevalence of celiac disease is increased among individuals with chronic kidney disease, also. The most frequent associations are with diabetic nephropathy, IgA nephropathy and urolithiasis. A gut-kidney axis has been recognized to play a significant role in chronic kidney diseases. This literature review aims to review the chronic renal pathology associated with celiac disease, with emphasis on childhood.

Identification of Susceptibility Modules and Genes for Cardiovascular Disease in Diabetic Patients Using WGCNA Analysis

OBJECTIVE

To identify susceptibility modules and genes for cardiovascular disease in diabetic patients using weighted gene coexpression network analysis (WGCNA).

METHODS

The raw data of GSE13760 were downloaded from the Gene Expression Omnibus (GEO) website. Genes with a false discovery rate < 0.05 and a log2 fold change ≥ 0.5 were included in the analysis. WGCNA was used to build a gene coexpression network, screen important modules, and filter the hub genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed for the genes in modules with clinical interest. Genes with a significance over 0.2 and a module membership over 0.8 were used as hub genes. Subsequently, we screened these hub genes in the published genome-wide SNP data of cardiovascular disease. The overlapped genes were defined as key genes.

RESULTS

Fourteen gene coexpression modules were constructed via WGCNA analysis. Module greenyellow was mostly significantly correlated with diabetes. The GO analysis showed that genes in the module greenyellow were mainly enriched in extracellular matrix organization, extracellular exosome, and calcium ion binding. The KEGG analysis showed that the genes in the module greenyellow were mainly enriched in antigen processing and presentation, phagosome. Fifteen genes were identified as hub genes. Finally, HLA-DRB1, LRP1, and MMP2 were identified as key genes.

CONCLUSION

This was the first study that used the WGCNA method to construct a coexpression network to explore diabetes-associated susceptibility modules and genes for cardiovascular disease. Our study identified a module and several key genes that acted as essential components in the etiology of diabetes-associated cardiovascular disease, which may enhance our fundamental knowledge of the molecular mechanisms underlying this disease.

Human Leukocyte Antigens (HLA) Genes Association in Type 1 Diabetic Nephropathy

BACKGROUND

Diabetic nephropathy is a common worldwide multifactorial disease where involvement of genetic factors is well etablished. The aim of this study was to investigate the HLA genes implication in the development of type 1 diabetic nephropathy.

METHODS

We performed a case- control study where one hundred and fifty subjects were examined. Patients were divided in two groups; with and without type 1 diabetic nephropathy. HLA typing was performed using Polymerase Chain Reaction- Sequence Specific Oligonucleotide (PCR- SSO) method. HLA association to clinical phenotype and HLA haplotype analysis was also investigated.

RESULTS

HLA B*51 is increased in patients without type 1 diabetic nephropathy (7.14% vs. 0 %, P <0.05, OR= 0), however no other studied alleles seem to have any effect (all P>0.05). Haplotype analysis also does not reveal any significant association, however, A*02-B*18-DRB1*03-DQA1*05- DQB1*03 haplotype shows a tendency to be associated with the development of diabetic nephropathy (P = 0.05).

CONCLUSION

These results suggest a protective effect of HLA B*51 allele from type 1 diabetic nephropathy. However, further studies are required in order to clarify its potential implication as a protective marker.

HLA-DRB1*03 as a risk factor for microalbuminuria in same duration of type 1 diabetes: a case control study

BACKGROUND

Increased urinary albumin excretion rate is the earliest clinical manifestation of diabetic nephropathy. The development of microalbuminuria in patients with type 1 diabetes mellitus (T1D) usually begins 5 to 15 years after the onset of diabetes. The rate of progression of diabetic nephropathy varies considerably among patients and not always can be explained solely by glycaemic control. The evidence suggests that genetic susceptibility may play a role in the development of diabetes microvascular complications, besides the presence of such risk factors as hyperglycaemia, hypertension, dyslipidaemia and smoking. The aim of the study was to evaluate a link between known genetic risk factors for type 1 diabetes mellitus (HLA-DR3/DR4) and microalbuminuria among patients with the same durations of diabetes.

METHODS

Ninety-nine patients with T1D at the age 18-35 years were recruited for the study. The urine albumin excretion rate was normal when <30 mg/24 h; microalbuminuria 30-300 mg/24 h. Genotypes were investigated in 39 patients with normal albumin excretion rate and duration of diabetes 13.46 ± 3.72 years and in 60 patients with microalbuminuria and duration of diabetes 15.28 ± 4.08 years (p = 0.11). Genetic typing of DR3 and DR4 antigens successfully was performed for 99 subjects. Statistical analysis was performed using SPSS v. 20.0.

RESULTS

Genotyping of 99 patients with T1D was performed: no DR3 and DR4 risk alleles were found in 22 (22.22 %) cases, DR3 alleles were present in 47 (47.48 %) cases, DR4 alleles in 25 (25.25 %) cases, and DR3/DR4 alleles in 5 (5.05 %) cases. The highest 24 h albumin excretion rate was found in patients with DRB1 gene expressed DR3 risk alleles group, the lowest - in patients with DRB1 gene with no expression of both DR3 and DR4 antigen. We confirmed the 1.87 (p = 0.021) increased relative risk for microalbuminuria in patients with DR3/DR3 alleles and same duration of diabetes. The distribution of DR3 and DR4 risk alleles was not associated with cardiovascular autonomic neuropathy both in patients with normal albumin excretion rate and microalbuminuria (1.6 vs 2.1; p = 0.21).

CONCLUSIONS

The 1.87 (p = 0.021) increased relative risk for microalbuminuria was found in patients with DR3/DR3 alleles and the same duration of diabetes.

Association between human leucocyte antigen subtypes and risk of end stage renal disease in Taiwanese: a retrospective study

Background

End stage renal disease (ESRD) is prevalent in Taiwan. Human leukocyte antigens (HLA) have been found to be associated with the pathogenesis of autoimmune diseases, allergies and inflammatory bowel diseases, and there are emerging evidences of correlations between HLA genotypes and renal diseases such as diabetic nephropathy, IgA nephropathy, and glomerulonephritis. The aim of this study is to investigate detailed HLA subtypes in a case-control study of Taiwanese individuals.

Methods

The polymorphisms of HLA class I and II antigens in ESRD patients and a healthy control group were retrospectively analyzed. The information of 141 ESRD patients was obtained from the medical record of the Keelung branch of Chang Gung Memorial Hospital and was compared to the HLA type of a control group comprized of 190 healthy unrelated Taiwanese from one of our previous studies. In order to standardize the HLA designation of prior low-resolution typings with the more advanced DNA based typings, all HLA-A, −B and -DR were analyzed using a low resolution serologic equivalent.

Results

The current work suggests that HLA-DR3 (odds ratio = 1.91, 95 % CI = 1.098–3.324, P = 0.024, Pc = 0.312) and HLA-DR11 (odds ratio = 2.06, 95 % CI = 1.133–3.761, P = 0.021, Pc = 0.273) may represent susceptibility risk factors for the development of ESRD in Taiwanese individuals. On the other hand, HLA-DR8 (odds ratio = 0.47, 95 % CI = 0.236–0.920, p = 0.027. Pc = 0.351) may be a protective factor. HLA-A and -B antigens did not show any contribution of progression to ESRD. However, we note that the significance of all these findings is lost when the results are corrected for multiple comparisons according to Bonferroni. Further investigation with a larger group of patients and control is needed to resolve this issue.

Conclusions

HLA typing might be a useful clinical method for screening patients with high risk of progression to ESRD.

Linkage Analysis of Genomic Regions Contributing to the Expression of Type 1 Diabetes Microvascular Complications and Interaction with HLA

We conducted linkage analysis to follow up earlier work on microvascular complications of type 1 diabetes (T1D). We analyzed 415 families (2,008 individuals) previously genotyped for 402 SNP markers spanning chromosome 6. We did linkage analysis for the phenotypes of retinopathy and nephropathy. For retinopathy, two linkage peaks were mapped: one located at the HLA region and another novel locus telomeric to HLA. For nephropathy, a linkage peak centromeric to HLA was mapped, but the linkage peak telomeric to HLA seen in retinopathy was absent. Because of the strong association of T1D with DRB1*03:01 and DRB1*04:01, we stratified our analyses based on families whose probands were positive for DRB1*03:01 or DRB1*04:01. When analyzing the DRB1*03:01-positive retinopathy families, in addition to the novel telomeric locus, one centromeric to HLA was identified at the same location as the nephropathy peak. When we stratified on DRB1*04:01-positive families, the HLA telomeric peak strengthened but the centromeric peak disappeared. Our findings showed that HLA and non-HLA loci on chromosome 6 are involved in T1D complications' expression. While the HLA region is a major contributor to the expression of T1D, our results suggest an interaction between specific HLA alleles and other loci that influence complications' expression.

Coeliac disease, gluten-free diet and the development and progression of albuminuria in children with type 1 diabetes

OBJECTIVES

Although a diagnosis of coeliac disease (CD) may be confronting to children with type 1 diabetes and their families, we hypothesize that children with CD have lower urinary albumin excretion, a marker of renal dysfunction.

RESEARCH DESIGN

Twenty-four children with type 1 diabetes and biopsy-proven CD, on a gluten-free diet for at least 1 yr, were recruited from a single paediatric diabetes clinic alongside 55 children with type 1 diabetes but without CD matched for age, gender, duration of diabetes, and glycaemic control.

RESULTS

Despite comparable diabetes exposure, glycaemic control and nutritional status, children with type 1 diabetes and CD had a lower urinary albumin creatinine ratio than in diabetic subjects without CD (0.9 ± 0.3 mg/mmol vs. 1.6 ± 0.3 mg/mmol; p = 0.01). Participants with CD also showed slower progression in albuminuria over 5-yr of follow-up while a small but significant increase was observed in the children with diabetes alone (1.6 ± 0.3 mg/mmol; follow-up 2.4 ± 0.5 mg/mmol; p = 0.02).

CONCLUSIONS

As urinary albumin excretion is continuously associated with the risk of kidney disease, it is possible to speculate that CD or its management confers a degree of renoprotection. Larger studies are required to test this hypothesis.

Type 1 diabetes mellitus and celiac disease: endothelial dysfunction

Many reports indicate a hypercoagulative state in diabetes mellitus as result of endothelial damage. Experimental evidence suggests that a metabolic derangement triggers a cascade of biochemical events that lead to vascular dysfunction. The net effect is to convert the endothelium from thromboresistant to thrombogenic surface. In literature, a strong association between type 1 diabetes mellitus (DM1) and celiac disease (CD) has been reported. We do not have information about the hemostatic system in these associated conditions. Our study aims at evaluating whether the presence of CD in a group of DM1 patients is associated with a different expression of some hemostatic factors and with a different manifestation and/or progression of microvascular complications of DM1 in comparison with patients with only diabetes. Ninety-four adult DM1 patients were enrolled in the study and subsequently screened for CD. Anti-endomysial antibodies (EMA) were positive in 13 of 94 DM1 patients (13.8%). CD diagnosis was confirmed by histology and organ culture. The mean age and duration of DM1 of patients also affected by CD were similar to those of only diabetic patients, but the metabolic control and the hemocoagulative parameters were significantly different between the two groups: DM1 patients also affected by CD presented significantly lower concentrations of glycosylated hemoglobin (HbA1c) (P < 0.05), cholesterol (P < 0.001), triglycerides (P < 0.001), factor VII antigen (FVII:ag) (P < 0.005), factor VII coagulant activity (FVII:c) (P < 0.05), and prothrombin degradation fragments (F1+2) (P < 0.001), as well as higher values of activated C protein (APC) (<0.001). No retinal abnormalities and no signs of renal damage were observed in DM1 patients also affected by CD. Our results suggest a potential protective role of CD in the prothrombotic state of DM1.

HLA class I and II alleles are associated with microvascular complications of type 1 diabetes

Although HLA alleles are associated with type 1 diabetes, association with microvascular complications remains controversial. We tested HLA association with complications in multiplex type 1 diabetes families. Probands from 425 type 1 diabetes families from the Human Biological Data Interchange (HBDI) collection were analyzed. The frequencies of specific HLA alleles in patients with complications were compared with the frequencies in complications-free patients. The complications we examined were: retinopathy, neuropathy, and nephropathy. We used logistic regression models with covariates to estimate odds ratios. We found that the DRB1*03:01 allele is a protective factor for complications (OR=0.58; p=0.03), as is the DQA1*05:01-DQB1*02:01 haplotype found in linkage disequilibrium with DRB1*03:01 (OR=0.59; p=0.031). The DRB1*04:01 allele showed no evidence of association (OR=1.13; p=0.624), although DRB1*04:01 showed suggestive evidence when the carriers of the protective DRB1*03:01 were removed from the analysis. The class II DQA1*03:01-DQB1*03:02 haplotype was not associated with complications, but the class I allele B*39:06 (OR=3.27; p=0.008) suggested a strong positive association with complications. Our results show that in type 1 diabetes patients, specific HLA alleles may be involved in susceptibility to, or protection from, microvascular complications.

A multicentre study of acute kidney injury in severe sepsis and septic shock: association with inflammatory phenotype and HLA genotype

BACKGROUND

To investigate the association between severity of acute kidney injury (AKI) and outcome, systemic inflammatory phenotype and HLA genotype in severe sepsis.

METHODOLOGY/PRINCIPAL FINDINGS

Prospective multicenter observational study done in 4 intensive care units in two university hospitals. Severe sepsis and septic shock patients with at least 2 organ failures based on the SOFA score were classified: 1) "no AKI", 2) "mild AKI" (grouping stage 1 and 2 of AKIN score) and 3) "severe AKI" (stage 3 of AKIN score). Sequential measurements: The vasopressor dependency index (VDI; dose and types of drugs) to evaluate the association between hemodynamic status and the development of early AKI; plasma levels of IL-10, macrophage migration inhibitory factor (MIF), IL-6 and HLA-DR monocyte expression. Genotyping of the 13 HLA-DRB1 alleles with deduction of presence of HLA-DRB3, -DRB4 and -DRB5 genes. We used multivariate analysis with competitive risk model to study associations. Overall, 176 study patients (146 with septic shock) were classified from AKIN score as "no AKI" (n = 43), "mild AKI" (n = 74) or "severe AKI" (n = 59). The VDI did not differ between groups of AKI. After adjustment, "mild and severe AKI" were an independent risk factor for mortality (HR 2.42 95%CI[1.01-5.83], p = 0.048 and HR 1.99 95%CI[1.30-3.03], p = 0.001 respectively). "Severe AKI" had higher levels of plasma IL-10, MIF and IL-6 compared to "no AKI" and mild AKI (p<0.05 for each), with no difference in mHLA-DR at day 0. HLA-DRB genotyping showed a significantly lower proportion of 4 HLA-DRB alleles among patients requiring renal replacement therapy (RRT) (58%) than in patients with severe AKI who did not receive RRT (84%) (p = 0.004).

CONCLUSIONS

AKI severity is independently associated with mortality and plasma IL-10, MIF or IL-6 levels. Presence of 4 alleles of HLA-DRB in severe AKI patients seems associated with a lower need of RRT.

Novel human leukocyte antigen class I and class II alleles identified by sequence-based typing in the Genetics of Kidneys in Diabetes (GoKinD) study population

Nine novel HLA class I and class II alleles were identified by sequence-based typing (SBT) in Caucasian participants from the Genetics of Kidneys in Diabetes (GoKinD) study. All novel alleles were single nucleotide substitutions. Seven alleles resulted in an amino acid change and two alleles were silent substitutions. The new alleles are as follows: five HLA-A alleles (*0132, *020121, *0344, *030107, *2507), one HLA-C allele (*0619), two HLA-DQB1 alleles (*0204, *0318), and one HLA-DPB1 allele (*1802). Eight of these new alleles were identified in participants with type 1 diabetes, three of whom also had diabetic nephropathy, and one new allele was identified in an unaffected parent of a participant with type 1 diabetes. All new alleles were isolated and characterized by use of single allele amplification (SAA) SBT; the new alleles were confirmed by sequence-specific primer (SSP) amplification.

Potential reno-protective effects of a gluten-free diet in type 1 diabetes

AIMS/HYPOTHESIS

Coeliac disease is common in type 1 diabetes. It is managed with a gluten-free diet, characterised by foods low in AGEs. We hypothesised that this diet would lead to lower plasma AGEs and be associated with reduced albuminuria.

METHODS

From a single paediatric clinic, we recruited 21 children with type 1 diabetes and biopsy-proven coeliac disease, and 38 individuals with diabetes alone. The groups were matched for age, sex, duration of disease and metabolic control. Participants completed a detailed clinical and dietary history. Blood samples were taken for HbA(1c), coeliac serology, thyroid function, serum IgA levels and plasma AGEs, and urine samples were obtained for estimation of the albumin/creatinine ratio (ACR).

RESULTS

All the individuals with coeliac disease were asymptomatic, with negative transglutaminase antibodies. There were no significant differences between the groups in terms of age (14 years), sex (29% male), duration of diabetes (7 years), mean HbA(1c) (8.3%), lipid levels or treatment regimens. However, children with diabetes and coeliac disease had twofold lower levels of urinary ACR than with those diabetes alone (p = 0.04). This was associated with lower levels of circulating AGEs (p = 0.03). These associations were independent of metabolic control, diabetes management and other potentially confounding variables, such as household exposure to cigarette smoke.

CONCLUSIONS/INTERPRETATION

Adherence to a gluten-free diet may provide additional benefits for individuals with coeliac disease, and potentially those with type 1 diabetes.

Sequence variants in the PLEKHH2 region are associated with diabetic nephropathy in the GoKinD study population

Nephropathy is a common microvascular complication of diabetes with a genetic component for disease development. Genetic analyses have implicated multiple chromosomal regions for disease susceptibility but no single locus can account for the majority of the genetic component. Here, we report a genetic analysis of the PLEKHH2 gene that was identified through a single nucleotide polymorphism (SNP) genome-wide association study (GWAS) for association with the development of diabetic nephropathy (DN) in the Genetics of Kidneys in Diabetes (GoKinD) study population. We initially examined the GWAS results from a subset of the GoKinD singleton population based on the two most common HLA diplotypes consisting of 112 cases and 148 controls. We observed two-adjacent markers mapping to the PLEKHH2 locus, rs1368086 and rs725238, each associated at P < 0.001. Additional SNPs were selected for linkage disequilibrium mapping and transmission disequilibrium testing (TdT) in 246 case trio families. A single marker, rs11886047, located upstream of the PLEKHH2 promoter was associated with DN by TdT in the case trios (P = 0.0307), and there was a increase of heterozygous genotypes in cases, relative to controls, from the 601 case and 577 control GoKinD singleton case/control population (P = 0.00256). These findings suggest that PLEKHH2, which has mRNA and protein expression exclusively in the glomerulus, may be a genetic risk factor for susceptibility to DN in the GoKinD population.