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1.
JAMA ; 322(6): 514-523, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31408136

RESUMO

Importance: High gluten intake during childhood may confer risk of celiac disease. Objectives: To investigate if the amount of gluten intake is associated with celiac disease autoimmunity and celiac disease in genetically at-risk children. Design, Setting, and Participants: The participants in The Environmental Determinants of Diabetes in the Young (TEDDY), a prospective observational birth cohort study designed to identify environmental triggers of type 1 diabetes and celiac disease, were followed up at 6 clinical centers in Finland, Germany, Sweden, and the United States. Between 2004 and 2010, 8676 newborns carrying HLA antigen genotypes associated with type 1 diabetes and celiac disease were enrolled. Screening for celiac disease with tissue transglutaminase autoantibodies was performed annually in 6757 children from the age of 2 years. Data on gluten intake were available in 6605 children (98%) by September 30, 2017. Exposures: Gluten intake was estimated from 3-day food records collected at ages 6, 9, and 12 months and biannually thereafter until the age of 5 years. Main Outcomes and Measures: The primary outcome was celiac disease autoimmunity, defined as positive tissue transglutaminase autoantibodies found in 2 consecutive serum samples. The secondary outcome was celiac disease confirmed by intestinal biopsy or persistently high tissue transglutaminase autoantibody levels. Results: Of the 6605 children (49% females; median follow-up: 9.0 years [interquartile range, 8.0-10.0 years]), 1216 (18%) developed celiac disease autoimmunity and 447 (7%) developed celiac disease. The incidence for both outcomes peaked at the age of 2 to 3 years. Daily gluten intake was associated with higher risk of celiac disease autoimmunity for every 1-g/d increase in gluten consumption (hazard ratio [HR], 1.30 [95% CI, 1.22-1.38]; absolute risk by the age of 3 years if the reference amount of gluten was consumed, 28.1%; absolute risk if gluten intake was 1-g/d higher than the reference amount, 34.2%; absolute risk difference, 6.1% [95% CI, 4.5%-7.7%]). Daily gluten intake was associated with higher risk of celiac disease for every 1-g/d increase in gluten consumption (HR, 1.50 [95% CI, 1.35-1.66]; absolute risk by age of 3 years if the reference amount of gluten was consumed, 20.7%; absolute risk if gluten intake was 1-g/d higher than the reference amount, 27.9%; absolute risk difference, 7.2% [95% CI, 6.1%-8.3%]). Conclusions and Relevance: Higher gluten intake during the first 5 years of life was associated with increased risk of celiac disease autoimmunity and celiac disease among genetically predisposed children.


Assuntos
Autoanticorpos/sangue , Doença Celíaca/etiologia , Proteínas na Dieta/efeitos adversos , Predisposição Genética para Doença , Glutens/efeitos adversos , Transglutaminases/imunologia , Autoimunidade , Doença Celíaca/epidemiologia , Doença Celíaca/genética , Doença Celíaca/imunologia , Pré-Escolar , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/genética , Registros de Dieta , Feminino , Glutens/administração & dosagem , Humanos , Incidência , Lactente , Masculino , Estudos Prospectivos , Risco
2.
Egypt J Immunol ; 26(1): 113-120, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31333001

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease associated with multiple genetics and environmental factors. The aim of the study is to determine the frequency of HLA-B*08 and HLA-B*39 and its linkage disequilibrium with common risk haplotypes DR3-DQA1*05-DQB1*02, and DR4-DQA1-03-DQB1*0302 among T1D Egyptian infants. And assess different environmental factors as early exposure to cow's milk, exclusive breast feeding, mode of delivery and low birth weight. Sixty eight diabetic infants and 120 healthy controls were studied. HLA-DQB1, and DQA1 alleles were identified using homogeneous PCR and oligonucleotide hybridization assays. HLA-B*08 and HLA-B*39 genes were identified using multiplex PCR. The results showed that early exposure to cow's milk before 6 months carry a significant risk for T1D (16% in patients versus 6.6%in control group, P value=0.03). HLA-B*08 frequency was significantly higher among T1D infants than in control group (14.5% in diabetic infants versus 5%in control group, P value=0.024). DR3-DQA1*05-DQB1*02, and DR4-DQA1-03-DQB1*0302 were significantly higher in diabetic infants than controls (P value < 0.001 and 0.004 respectively). HLA-B*08 gene was found in (15.5%) of DR3-DQA1*05-DQB1*02 positive cases while in control group it was found in (13.5%) (P value=0.8). In conclusion, HLA-B*08 gene carry a risk for T1D in Egyptian infants, while DR3-DQA1*05-DQB1*02 haplotype lacks linkage disequilibrium with HLA-B*08 among T1D infants. Further studies are needed to determine which HLA-B gene is strongly linked to DR3-DQA1*05-DQB1*02 haplotype in T1D infants other than HLA-B*08 and HLA-B*18.


Assuntos
Diabetes Mellitus Tipo 1/genética , Antígenos HLA-B/genética , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Antígeno HLA-DR3/genética , Desequilíbrio de Ligação , Leite , Alelos , Animais , Estudos de Casos e Controles , Bovinos , Egito , Predisposição Genética para Doença , Haplótipos , Humanos , Lactente , Fatores de Risco
4.
N Engl J Med ; 381(7): 603-613, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31180194

RESUMO

BACKGROUND: Type 1 diabetes is a chronic autoimmune disease that leads to destruction of insulin-producing beta cells and dependence on exogenous insulin for survival. Some interventions have delayed the loss of insulin production in patients with type 1 diabetes, but interventions that might affect clinical progression before diagnosis are needed. METHODS: We conducted a phase 2, randomized, placebo-controlled, double-blind trial of teplizumab (an Fc receptor-nonbinding anti-CD3 monoclonal antibody) involving relatives of patients with type 1 diabetes who did not have diabetes but were at high risk for development of clinical disease. Patients were randomly assigned to a single 14-day course of teplizumab or placebo, and follow-up for progression to clinical type 1 diabetes was performed with the use of oral glucose-tolerance tests at 6-month intervals. RESULTS: A total of 76 participants (55 [72%] of whom were ≤18 years of age) underwent randomization - 44 to the teplizumab group and 32 to the placebo group. The median time to the diagnosis of type 1 diabetes was 48.4 months in the teplizumab group and 24.4 months in the placebo group; the disease was diagnosed in 19 (43%) of the participants who received teplizumab and in 23 (72%) of those who received placebo. The hazard ratio for the diagnosis of type 1 diabetes (teplizumab vs. placebo) was 0.41 (95% confidence interval, 0.22 to 0.78; P = 0.006 by adjusted Cox proportional-hazards model). The annualized rates of diagnosis of diabetes were 14.9% per year in the teplizumab group and 35.9% per year in the placebo group. There were expected adverse events of rash and transient lymphopenia. KLRG1+TIGIT+CD8+ T cells were more common in the teplizumab group than in the placebo group. Among the participants who were HLA-DR3-negative, HLA-DR4-positive, or anti-zinc transporter 8 antibody-negative, fewer participants in the teplizumab group than in the placebo group had diabetes diagnosed. CONCLUSIONS: Teplizumab delayed progression to clinical type 1 diabetes in high-risk participants. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT01030861.).


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Complexo CD3/antagonistas & inibidores , Diabetes Mellitus Tipo 1/prevenção & controle , Adolescente , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Criança , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Progressão da Doença , Método Duplo-Cego , Exantema/induzido quimicamente , Feminino , Teste de Tolerância a Glucose , Antígeno HLA-DR3 , Antígeno HLA-DR4 , Humanos , Contagem de Linfócitos , Linfopenia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Linfócitos T/imunologia , Adulto Jovem
5.
PLoS Genet ; 15(6): e1008178, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31199784

RESUMO

Type 1 diabetes (T1D) is a chronic multi-factorial disorder characterized by the immune-mediated destruction of insulin-producing pancreatic beta cells. Variations at a large number of genes influence susceptibility to spontaneous autoimmune T1D in non-obese diabetic (NOD) mice, one of the most frequently studied animal models for human disease. The genetic analysis of these mice allowed the identification of many insulin-dependent diabetes (Idd) loci and candidate genes, one of them being Cd101. CD101 is a heavily glycosylated transmembrane molecule which exhibits negative-costimulatory functions and promotes regulatory T (Treg) function. It is abundantly expressed on subsets of lymphoid and myeloid cells, particularly within the gastrointestinal tract. We have recently reported that the genotype-dependent expression of CD101 correlates with a decreased susceptibility to T1D in NOD.B6 Idd10 congenic mice compared to parental NOD controls. Here we show that the knockout of CD101 within the introgressed B6-derived Idd10 region increased T1D frequency to that of the NOD strain. This loss of protection from T1D was paralleled by decreased Gr1-expressing myeloid cells and FoxP3+ Tregs and an enhanced accumulation of CD4-positive over CD8-positive T lymphocytes in pancreatic tissues. As compared to CD101+/+ NOD.B6 Idd10 donors, adoptive T cell transfers from CD101-/- NOD.B6 Idd10 mice increased T1D frequency in lymphopenic NOD scid and NOD.B6 Idd10 scid recipients. Increased T1D frequency correlated with a more rapid expansion of the transferred CD101-/- T cells and a lower proportion of recipient Gr1-expressing myeloid cells in the pancreatic lymph nodes. Fewer of the Gr1+ cells in the recipients receiving CD101-/- T cells expressed CD101 and the cells had lower levels of IL-10 and TGF-ß mRNA. Thus, our results connect the Cd101 haplotype-dependent protection from T1D to an anti-diabetogenic function of CD101-expressing Tregs and Gr1-positive myeloid cells and confirm the identity of Cd101 as Idd10.


Assuntos
Antígenos CD/genética , Antígenos Ly/genética , Diabetes Mellitus Tipo 1/genética , Pâncreas/metabolismo , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diabetes Mellitus Tipo 1/patologia , Regulação da Expressão Gênica/genética , Predisposição Genética para Doença , Haplótipos/genética , Humanos , Linfonodos/metabolismo , Linfonodos/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Células Mieloides/imunologia , Células Mieloides/metabolismo , Pâncreas/patologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
6.
Gene ; 707: 1-8, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31054364

RESUMO

BACKGROUND: Genome-wide association studies have captured a large proportion of genetic variation related to type 1 diabetes mellitus (T1D). However, most of these studies are performed in populations of European ancestry and therefore the disease risk estimations can be inaccurate when extrapolated to other world populations. METHODS: We conducted a case-control study in 1866 individuals from the three major populations of the Republic of Bashkortostan (Russians, Tatars, and Bashkirs) in Russian Federation, using single-locus and multilocus approach to identify genetic predictors of T1D. RESULTS: We found that LTA rs909253 and TNF rs1800629 polymorphisms were associated with T1D in the group of Tatars. Meta-analysis of the association study results in the three ethnic groups has confirmed the association between the T1D risk and LTA rs909253 genetic variant. LTA rs909253 and TNF rs1800629 loci were also featured in combinations most significantly associated with T1D. CONCLUSION: Our findings suggest that LTA rs909253 and TNF rs1800629 polymorphisms are associated with the risk of T1D both independently and in combination with polymorphic markers in other inflammatory genes, and the analysis of multi-allelic combinations provides valuable insight in the study of polygenic traits.


Assuntos
Diabetes Mellitus Tipo 1/genética , Linfotoxina-alfa/genética , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/genética , Adolescente , Adulto , Bashkiria/etnologia , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/etnologia , Feminino , Predisposição Genética para Doença/etnologia , Estudo de Associação Genômica Ampla , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
J Mol Histol ; 50(3): 239-251, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31049798

RESUMO

Reduced expression of endothelial nitric oxide synthase (eNOS) is a hallmark of endothelial dysfunction in diabetes, which predisposes diabetic patients to numerous cardiovascular complications including blunted angiogenesis. The Krüppel-like factor (KLF) five has been implicated as a central regulator of cardiovascular remodeling, but its role in endothelial cells (ECs) remains poorly understood. We show here that expression of endothelial KLF5 was significantly increased in the ECs from mouse diabetes mellitus type 2 (T2DM) model, when compared to non-diabetic or T1DM mouse. KLF5 up-regulation by insulin was dependent on activation of multiple pathways, including mammalian target of rapamycin, oxidative stress and Protein kinase C pathways. Hyperinsulinemia-induced KLF5 inhibited endothelial function and migration, and thereby compromised in vitro and in vivo angiogenesis. Mechanistically, KLF5 acted in concert with the MTA1 coregulator to negatively regulate NOS3 transcription, thereby leading to the diminished eNOS levels in ECs. Conversely, potentiation of cGMP content (the essential downstream effector of eNOS signaling) by pharmacological approaches successfully rescued the endothelial proliferation and in vitro tube formation, in the HUVECs overexpressing the exogenous KLF5. Collectively, the available data suggest that the augmentation of endothelial KLF5 expression by hyperinsulinemia may represent a novel mechanism for negatively regulating eNOS expression, and may thus help to explain for the T2DM-related endothelial dysfunction at the transcriptional level.


Assuntos
Hiperinsulinismo/genética , Fatores de Transcrição Kruppel-Like/genética , Neovascularização Patológica/genética , Óxido Nítrico Sintase Tipo III/genética , Animais , Movimento Celular/genética , Proliferação de Células/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Expressão Gênica/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Hiperinsulinismo/patologia , Masculino , Camundongos , Estresse Oxidativo/genética , Proteína Quinase C/genética , Transdução de Sinais/genética
8.
Mol Med Rep ; 19(5): 3989-4000, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30942443

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease that is typically diagnosed in children. The aim of the present study was to identify potential genes involved in the pathogenesis of childhood T1D. Two datasets of mRNA expression in children with T1D were obtained from the Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) in children with T1D were identified. Functional analysis was performed and a protein­protein interaction (PPI) network was constructed, as was a transcription factor (TF)­target network. The expression of selected DEGs was further assessed using reverse transcription­quantitative polymerase chain reaction (RT­qPCR) analysis. Electronic validation and diagnostic value analysis of the identified DEGs [cytokine inducible SH2 containing protein (CISH), SR­related CTD associated factor 11 (SCAF11), estrogen receptor 1 (ESR1), Rho GTPase activating protein 25 (ARHGAP25), major histocompatibility complex, class II, DR ß4 (HLA­DRB4) and interleukin 23 subunit α (IL23A)] was performed in the GEO dataset. Compared with the normal control group, a total of 1,467 DEGs with P<0.05 were identified in children with T1D. CISH and SCAF11 were determined to be the most up­ and downregulated genes, respectively. Heterogeneous nuclear ribonucleoprotein D (HNRNPD; degree=33), protein kinase AMP­activated catalytic subunit α1 (PRKAA1; degree=11), integrin subunit α4 (ITGA4; degree=8) and ESR1 (degree=8) were identified in the PPI network as high­degree genes. ARHGAP25 (degree=12), HNRNPD (degree=10), HLA­DRB4 (degree=10) and IL23A (degree=9) were high­degree genes identified in the TF­target network. RT­qPCR revealed that the expression of HNRNPD, PRKAA1, ITGA4 and transporter 2, ATP binding cassette subfamily B member was consistent with the results of the integrated analysis. Furthermore, the results of the electronic validation were consistent with the bioinformatics analysis. SCAF11, CISH and ARHGAP25 were identified to possess value as potential diagnostic markers for children with T1D. In conclusion, identifying DEGs in children with T1D may contribute to our understanding of its pathogenesis, and such DEGs may be used as diagnostic biomarkers for children with T1D.


Assuntos
Diabetes Mellitus Tipo 1/diagnóstico , Transcriptoma , Área Sob a Curva , Estudos de Casos e Controles , Criança , Diabetes Mellitus Tipo 1/genética , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Redes Reguladoras de Genes , Humanos , Masculino , Mapas de Interação de Proteínas/genética , Curva ROC , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo
9.
Nat Med ; 25(5): 805-813, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31011203

RESUMO

Chronic inflammation is postulated to be involved in the development of end-stage renal disease in diabetes, but which specific circulating inflammatory proteins contribute to this risk remain unknown. To study this, we examined 194 circulating inflammatory proteins in subjects from three independent cohorts with type 1 and type 2 diabetes. In each cohort, we identified an extremely robust kidney risk inflammatory signature (KRIS), consisting of 17 proteins enriched in tumor necrosis factor-receptor superfamily members, that was associated with a 10-year risk of end-stage renal disease. All these proteins had a systemic, non-kidney source. Our prospective study findings provide strong evidence that KRIS proteins contribute to the inflammatory process underlying end-stage renal disease development in both types of diabetes. These proteins point to new therapeutic targets and new prognostic tests to identify subjects at risk of end-stage renal disease, as well as biomarkers to measure responses to treatment of diabetic kidney disease.


Assuntos
Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/etiologia , Falência Renal Crônica/sangue , Falência Renal Crônica/etiologia , Adulto , Idoso , Biomarcadores/sangue , Proteínas Sanguíneas/genética , Proteínas Sanguíneas/metabolismo , Estudos de Coortes , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Nefropatias Diabéticas/genética , Progressão da Doença , Feminino , Humanos , Mediadores da Inflamação/sangue , Falência Renal Crônica/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Proteômica , Receptores do Fator de Necrose Tumoral/sangue , Receptores do Fator de Necrose Tumoral/genética , Fatores de Risco
10.
Gene ; 703: 120-124, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30959073

RESUMO

AIMS: Given the participation of oxidative stress in the pathogenesis of diabetic complications, we evaluated, in type 1 diabetes (T1D) individuals, the association between diabetic retinopathy (DR) and functional single nucleotide polymorphisms (SNPs) in regulatory regions of two genes belonging to the antioxidant glutathione (GSH) system: rs17883901 in GCLC and rs713041 in GPX4. METHODS: A cross-sectional case-control study included 288 individuals (61% women, 34[±11] years old, diabetes duration of 22[±9] years, mean [±SD]) sorted according to DR stages: absence of DR (ADR), non-proliferative DR (NPDR) and proliferative DR (PDR). SNPs were genotyped by real-time PCR using fluorescent labelled probes. Logistic regression models with adjustment for confounding covariates were employed. RESULTS: The presence of at least one T-allele of rs17883901 in GCLC was an independent risk factor for PDR (OR 4.13, 95% CI 1.38-13.66, p = 0.014) in a polytomous regression model (PDR versus ADR). The presence of at least one T-allele of rs713041 in GPX4 conferred protection against PDR (OR 0.30, 95% CI 0.11-0.80, p = 0.017) in female T1D individuals. CONCLUSION: The functional SNPs rs17883901 and rs713041 modulate the risk for PDR in the studied population of T1D individuals, widening the spectrum of candidate genes for this complication.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Retinopatia Diabética/genética , Glutamato-Cisteína Ligase/genética , Glutationa Peroxidase/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idade de Início , Estudos de Casos e Controles , Estudos Transversais , Diabetes Mellitus Tipo 1/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Neurosci Lett ; 703: 11-18, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-30851305

RESUMO

Diabetes related cognitive impairment is a severe complication. The diabetes-induced cognitive impairment is associated with insulin resistance and glucose-induced neuron apoptosis in the brain. We intended to investigate the association of long non-coding RNAs with diabetes-induced cognitive impairment in rats. Here, Type 1diabetes (T1D) rat model was induced using streptozotocin (STZ). The diabetic rats showed significant cognitive dysfunction, with increased latency period to find the hidden platform during morris water maze test. The brain injury and reduced neuronsin STZ-induced diabetic rats was determined using hematoxylin and eosin staining and Nissl's staining. We performed the LncRNA microarray analysis and identified 101 differentially expressed lncRNAs in streptozotocin (STZ)-induced type 1 diabetes (T1D) comparing with control. Among these lncRNA, LOC103690121 was upregulated. in vitro glucose treatment in hippocampal neurons showed LOC103690121 and neuron apoptosis was increased by glucose treatment. Transfection experiments showed LOC103690121 overexpression promoted neuron apoptosis, and its inhibition suppressed glucose-induced apoptosis. Western blot analysis showed that the expression profiles of apoptosis related proteins (cleaved-caspase-3, -8, -9, and Bax) were in line with LOC103690121 expression, while the profiles of Bcl-2 and PI3K/Akt signaling pathway was contrast to LOC103690121 expression. In conclusion, the results of our study confirmed lncRNA LOC103690121 promoted STZ-induced cognitive impairment in diabetic rats by promoting neuron apoptosis through PI3K/Akt signaling pathway.


Assuntos
Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 1/genética , Hipocampo/patologia , Neurônios/patologia , RNA Longo não Codificante/genética , Animais , Apoptose , Proliferação de Células , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/genética , Transtornos Cognitivos/patologia , Complicações do Diabetes/induzido quimicamente , Complicações do Diabetes/genética , Complicações do Diabetes/patologia , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/patologia , Glucose/metabolismo , Glucose/farmacologia , Hipocampo/efeitos dos fármacos , Neurônios/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais , Estreptozocina
12.
Pharmacol Rep ; 71(2): 282-288, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30826568

RESUMO

BACKGROUND: After the onset of type 1 diabetes mellitus (T1DM), preservation of the residual ß-cell function can help good metabolic control. The aim of this study was to evaluate the effect of vitamin D and its receptor gene polymorphisms on residual ß-cells function. METHODS: One hundred and one children with T1DM (new cases) older than 5 years were selected. Vitamin D receptor (VDR) gene polymorphisms, vitamin D (VD), fasting and stimulated C-peptide (FCP and SCP) levels were measured within 1.5 and 4.5 month after the diagnosis of disease. Kruskal-Wallis and Mann-whitney U test were used for comparing the study groups. Generalized estimating equation (GEE) model was used for the estimation of association between VD and VDR gene polymorphisms with FCP and SCP after adjustment for comorbid variables. RESULTS: The most frequent genotypes and alleles in TaqI, FokI, BsmI and ApaI polymorphisms were TT (50%) and allele T (68.88%), FF (59.2%) and allele F (77.04%), Bb (41.8%) and allele b (61.73%), and Aa (53.1%) and allele A (63.29%) respectively. In children with higher VD levels, the C-peptide (CP) levels were elevated. Also we observed: the tt genotype associated with increasing SCP levels compared with TT genotype; the bb and Bb genotypes were associated with increasing both FCP and SCP in comparison to BB; and the aa and Aa genotypes were associated with decreasing FCP in comparison to the AA genotype. CONCLUSIONS: Sufficient levels of VD (more than 30 ng/ml) can preserve residual ß-cells and insulin secretion.


Assuntos
Diabetes Mellitus Tipo 1/genética , Células Secretoras de Insulina/metabolismo , Receptores de Calcitriol/genética , Vitamina D/metabolismo , Adolescente , Alelos , Criança , Pré-Escolar , Estudos de Coortes , Diabetes Mellitus Tipo 1/fisiopatologia , Feminino , Genótipo , Humanos , Secreção de Insulina/genética , Masculino , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fatores de Tempo
13.
Proc Natl Acad Sci U S A ; 116(15): 7581-7590, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30910956

RESUMO

Genome-wide association studies (GWASs) have revealed 59 genomic loci associated with type 1 diabetes (T1D). Functional interpretation of the SNPs located in the noncoding region of these loci remains challenging. We perform epigenomic profiling of two enhancer marks, H3K4me1 and H3K27ac, using primary TH1 and TREG cells isolated from healthy and T1D subjects. We uncover a large number of deregulated enhancers and altered transcriptional circuitries in both cell types of T1D patients. We identify four SNPs (rs10772119, rs10772120, rs3176792, rs883868) in linkage disequilibrium (LD) with T1D-associated GWAS lead SNPs that alter enhancer activity and expression of immune genes. Among them, rs10772119 and rs883868 disrupt the binding of retinoic acid receptor α (RARA) and Yin and Yang 1 (YY1), respectively. Loss of binding by YY1 also results in the loss of long-range enhancer-promoter interaction. These findings provide insights into how noncoding variants affect the transcriptomes of two T-cell subtypes that play critical roles in T1D pathogenesis.


Assuntos
Diabetes Mellitus Tipo 1 , Elementos Facilitadores Genéticos , Polimorfismo de Nucleotídeo Único , Receptor alfa de Ácido Retinoico , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Fator de Transcrição YY1 , Pré-Escolar , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Epigenômica , Feminino , Estudo de Associação Genômica Ampla , Humanos , Lactente , Células Jurkat , Masculino , Receptor alfa de Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico/imunologia , Fatores de Risco , Linfócitos T Reguladores/patologia , Células Th1/patologia , Fator de Transcrição YY1/genética , Fator de Transcrição YY1/imunologia
14.
Inflamm Res ; 68(4): 275-284, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30798334

RESUMO

OBJECTIVES: Both type 1 diabetes (T1D) and type 2 diabetes (T2D) are classified as forms of diabetes mellitus (DM) and commonly considered inflammatory process. Intercellular adhesion molecule-1 (ICAM-1) is involved in the development and progression of diabetes mellitus. However, the genetic association between ICAM-1 rs5498, and T1D and T2D risk was inconclusive. MATERIALS AND METHODS: A meta-analysis by searching the PubMed, Embase, Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI) databases was performed out. The pooled odds ratio (OR) and 95% confidence interval (CI) were used to describe the strength of association of T1D and T2D risk. RESULTS: A total of 14 studies encompassing 3233 cases and 2884 controls were included in the present meta-analysis. Significant associations were found between the allele and recessive models of ICAM1 rs5498 and DM in Asian population (allele: OR 1.13; 95% CI 1.03-1.23, p = 0.008; recessive: OR 1.25; 95% CI 1.06-1.48, p = 0.008), but not in Caucasian population (p > 0.05). In addition, the allele model of rs5498 was found to be significantly associated with the increased risk of T2D (OR 1.10; 95% CI 1.01-1.21, p = 0.03), but not T1D (p > 0.05). CONCLUSIONS: The ICAM1 rs5498 might be a susceptible factor for T2D, but not T1D. And the allele and recessive models of ICAM1 rs5498 might be a risk factor in Asian population.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Molécula 1 de Adesão Intercelular/genética , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único
15.
Diabetes Res Clin Pract ; 149: 9-17, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30710658

RESUMO

Published information on diabetes in Pakistani youth is limited. We aimed to investigate the demographic, clinical, and biochemical features, and HLA-DRB1 alleles in new cases of diabetes affecting children and adolescents <22 years of age. The study was conducted at Baqai Institute of Diabetology and Endocrinology in Karachi from June 2013-December 2015. One hundred subjects aged <22 years at diagnosis were enrolled. Demographic characteristics, clinical information, biochemical parameters (blood glucose, HbA1c, C-peptide, glutamic acid decarboxylase 65 (GAD65) and islet antigen 2 (IA-2) autoantibodies) were measured. DNA from 100 subjects and 200 controls was extracted and genotyped for HLA-DRB1 using high-resolution genotyping technology. Ninety-nine subjects were clinically diagnosed as type 1 diabetes (T1D) and one as type 2 diabetes (T2D). Of the 99 with T1D, 57 (57.6%) were males and 42 (42.4%) females, with mean age at diagnosis 11.0 ±â€¯5.2 years (range 1.6-21.7 years) and peaks at six and fifteen years. Fifty-seven subjects were assessed within one month of diagnosis and all within eleven months. For the subjects diagnosed as T1D, mean C-peptide was 0.63 ±â€¯0.51 nmol/L (1.91 ±â€¯1.53 ng/mL), with 16 (16.2%) IA2 positive, 53 (53.5%) GAD-65 positive, and 10 (10.1%) positive for both autoantibodies. In T1D patients, the allele DRB1*03:01 demonstrated highly significant T1D association (p < 10-16), with no apparent risk conferred by DRB1*04:xx alleles. CONCLUSIONS: Heterogeneous forms of T1D appear more common in children and youth in Pakistan than in European populations. Individual understanding of such cases could enable improved management strategies and healthier outcomes.


Assuntos
Autoanticorpos/metabolismo , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/genética , Cadeias HLA-DRB1/genética , Adolescente , Adulto , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/patologia , Feminino , Cadeias HLA-DRB1/metabolismo , Humanos , Lactente , Masculino , Paquistão , Adulto Jovem
16.
Clin Appl Thromb Hemost ; 25: 1076029618825311, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30760002

RESUMO

BACKGROUND AND AIM:: Hyperglycemia in type 1 diabetes (T1D) is accompanied by endothelial cell dysfunction which is known to contribute to the pathogenesis of cardiovascular disorders. The aim of the current study was to explore the profile of circulating endothelial progenitor cells (EPCs), circulating endothelial cells (CECs), endothelial and platelet derived micropaticles (EMPs, PMPs) and total microparticles (TMPs), in T1D children in relation to each other and to the metabolic disorders accompanying T1D. PATIENTS AND METHODS:: Thirty T1D patients and 20 age and sex matched healthy volunteers were assessed for HbA1c level and lipid profile. Quantification of CECs, EPCs, TMPs, EMPs and PMPs was done by flow cytometry. RESULTS:: The mean levels of EMPs, PMPs, TMPs and CECs were significantly higher in diabetic children compared to controls. Meanwhile, the levels of EPCs were significantly lower in diabetic children compared to controls. Both PMPs and CECs showed the highest significant differences between patients and controls and their levels were directly related to HbA1c, total cholesterol, LDL and triglycerides. A moderate correlation was observed between the frequency of PMPs and CECs. EPCs revealed negative correlations with both LDL and triglycerides. TMPs were only related to LDL, while EMPs were only related to HbA1c. CONCLUSION:: Although there is disturbance in the levels of EMPs, PMPs, TMPs, CECs and EPCs in type 1 diabetic children compared to the controls, only the levels of PMPs and CECs were closely affected by the poor glycemic control and dyslipidemia occurring in T1D; thus may contribute to a higher risk of cardiovascular diseases.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/metabolismo , Células Progenitoras Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Criança , Diabetes Mellitus Tipo 1/patologia , Feminino , Citometria de Fluxo , Humanos , Masculino
17.
Int J Biol Macromol ; 127: 657-664, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30710592

RESUMO

Zinc transporter 8 (ZnT8) is a novel immunodominant autoantigen, associated with Type-1 diabetes. A non-synonymous polymorphism (R325W) in its gene is associated with Type-2 diabetes. In this study, we performed an in silico B cell epitope prediction followed by wetlab validation of ZnT8. Apart from the previously characterized polymorphic epitope (BE-5 TAASR*DS), two novel epitopes BE-2 (N-terminus) and BE-6 (C-terminus) were identified. Wet lab validation of these epitopes was carried out by measuring ZnT8 specific isotypes (IgG, IgM and IgA) in the sera of Normal Glucose Tolerant (NGT), Type-1 diabetic (T1DM) and Type-2 diabetic (T2DM) patients by indirect ELISA. Unexpectedly, compared to NGT, significantly decreased levels of IgG and IgA isotypes was seen in T1DM subjects without complications. IgM levels were reduced in T1DM subjects with retinopathy. Newly diagnosed T1DM subjects initiated on insulin therapy showed an increase in IgA and decrease in IgM titre. Like T1DM, significantly reduced level of IgG, IgM and IgA was seen in T2DM subjects. For the first time, we have identified novel cryptic B cell epitopes in ZnT8 autoantigen against which the naturally occurring autoantibody levels were found to be reduced in diabetes.


Assuntos
Autoanticorpos , Autoantígenos , Simulação por Computador , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Epitopos de Linfócito B , Adulto , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoantígenos/genética , Autoantígenos/imunologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/imunologia , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Feminino , Humanos , Masculino , Transportador 8 de Zinco/genética , Transportador 8 de Zinco/imunologia
19.
Diabetes Care ; 42(3): 406-415, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30659077

RESUMO

OBJECTIVE: Genetic risk scores (GRS) have been developed that differentiate individuals with type 1 diabetes from those with other forms of diabetes and are starting to be used for population screening; however, most studies were conducted in European-ancestry populations. This study identifies novel genetic variants associated with type 1 diabetes risk in African-ancestry participants and develops an African-specific GRS. RESEARCH DESIGN AND METHODS: We generated single nucleotide polymorphism (SNP) data with the ImmunoChip on 1,021 African-ancestry participants with type 1 diabetes and 2,928 control participants. HLA class I and class II alleles were imputed using SNP2HLA. Logistic regression models were used to identify genome-wide significant (P < 5.0 × 10-8) SNPs associated with type 1 diabetes in the African-ancestry samples and validate SNPs associated with risk in known European-ancestry loci (P < 2.79 × 10-5). RESULTS: African-specific (HLA-DQA1*03:01-HLA-DQB1*02:01) and known European-ancestry HLA haplotypes (HLA-DRB1*03:01-HLA-DQA1*05:01-HLA-DQB1*02:01, HLA-DRB1*04:01-HLA-DQA1*03:01-HLA-DQB1*03:02) were significantly associated with type 1 diabetes risk. Among European-ancestry defined non-HLA risk loci, six risk loci were significantly associated with type 1 diabetes in subjects of African ancestry. An African-specific GRS provided strong prediction of type 1 diabetes risk (area under the curve 0.871), performing significantly better than a European-based GRS and two polygenic risk scores in independent discovery and validation cohorts. CONCLUSIONS: Genetic risk of type 1 diabetes includes ancestry-specific, disease-associated variants. The GRS developed here provides improved prediction of type 1 diabetes in African-ancestry subjects and a means to identify groups of individuals who would benefit from immune monitoring for early detection of islet autoimmunity.


Assuntos
Grupo com Ancestrais do Continente Africano/genética , Diabetes Mellitus Tipo 1/etnologia , Diabetes Mellitus Tipo 1/genética , Testes Genéticos , Antígenos HLA-D/genética , Grupo com Ancestrais do Continente Africano/estatística & dados numéricos , Alelos , Estudos de Casos e Controles , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Predisposição Genética para Doença , Testes Genéticos/métodos , Testes Genéticos/normas , Estudo de Associação Genômica Ampla , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Haplótipos , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Valor Preditivo dos Testes , Projetos de Pesquisa , Fatores de Risco
20.
Diabetes ; 68(4): 787-795, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30626607

RESUMO

The heterozygous DQ2/8 (DQA1*05:01-DQB1*02:01/DQA1*03:01-DQB1*03:02) genotype confers the highest risk in type 1 diabetes (T1D), whereas the DQ6/8 (DQA1*02:01-DQB1*06:02/DQA1*03:01-DQB1*03:02) genotype is protective. The mechanism of dominant protection by DQ6 (DQB1*06:02) is unknown. We tested the hypothesis that DQ6 interferes with peptide binding to DQ8 by competition for islet epitope ("epitope stealing") by analysis of the islet ligandome presented by HLA-DQ6/8 and -DQ8/8 on dendritic cells pulsed with islet autoantigens preproinsulin (PPI), GAD65, and IA-2, followed by competition assays using a newly established "epitope-stealing" HLA/peptide-binding assay. HLA-DQ ligandome analysis revealed a distinct DQ6 peptide-binding motif compared with the susceptible DQ2/8 molecules. PPI and IA-2 peptides were identified from DQ6, of DQ6/8 heterozygous dendritic cells, but no DQ8 islet peptides were retrieved. Insulin B6-23, a highly immunogenic CD4 T-cell epitope in patients with T1D, bound to both DQ6 and DQ8. Yet, binding of InsB6-23 to DQ8 was prevented by DQ6. We obtained first functional evidence of a mechanism of dominant protection from disease, in which HLA molecules associated with protection bind islet epitopes in a different, competing, HLA-binding register, leading to "epitope stealing" and conceivably diverting the immune response from islet epitopes presented by disease-susceptible HLA molecules in the absence of protective HLA.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Epitopos de Linfócito T/imunologia , Antígenos HLA-DQ/imunologia , Linhagem Celular Tumoral , Diabetes Mellitus Tipo 1/genética , Antígenos HLA-DQ/genética , Haplótipos , Humanos
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