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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.).
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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 JovemRESUMO
AIMS/HYPOTHESIS: Young children who develop multiple autoantibodies (mAbs) are at very high risk for type 1 diabetes. We assessed whether a population with mAbs detected by screening is also at very high risk, and how risk varies according to age, type of autoantibodies and metabolic status. METHODS: Type 1 Diabetes TrialNet Pathway to Prevention participants with mAbs (n = 1815; age, 12.35 ± 9.39 years; range, 1-49 years) were analysed. Type 1 diabetes risk was assessed according to age, autoantibody type/number (insulin autoantibodies [IAA], glutamic acid decarboxylase autoantibodies [GADA], insulinoma-associated antigen-2 autoantibodies [IA-2A] or zinc transporter 8 autoantibodies [ZnT8A]) and Index60 (composite measure of fasting C-peptide, 60 min glucose and 60 min C-peptide). Cox regression and cumulative incidence curves were utilised in this cohort study. RESULTS: Age was inversely related to type 1 diabetes risk in those with mAbs (HR 0.97 [95% CI 0.96, 0.99]). Among participants with 2 autoantibodies, those with GADA had less risk (HR 0.35 [95% CI 0.22, 0.57]) and those with IA-2A had higher risk (HR 2.82 [95% CI 1.76, 4.51]) of type 1 diabetes. Those with IAA and GADA had only a 17% 5 year risk of type 1 diabetes. The risk was significantly lower for those with Index60 <1.0 (HR 0.23 [95% CI 0.19, 0.30]) vs those with Index60 values ≥1.0. Among the 12% (225/1815) ≥12.0 years of age with GADA positivity, IA-2A negativity and Index60 <1.0, the 5 year risk of type 1 diabetes was 8%. CONCLUSIONS/INTERPRETATION: Type 1 diabetes risk varies substantially according to age, autoantibody type and metabolic status in individuals screened for mAbs. An appreciable proportion of older children and adults with mAbs appear to have a low risk of progressing to type 1 diabetes at 5 years. With this knowledge, clinical trials of type 1 diabetes prevention can better target those most likely to progress.
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Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/diagnóstico , Estado Pré-Diabético/patologia , Adolescente , Adulto , Autoanticorpos/análise , Doenças Autoimunes/sangue , Doenças Autoimunes/genética , Doenças Autoimunes/patologia , Criança , Pré-Escolar , Estudos de Coortes , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Progressão da Doença , Feminino , Seguimentos , Predisposição Genética para Doença , Teste de Tolerância a Glucose , Humanos , Individualidade , Lactente , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Estado Pré-Diabético/sangue , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/genética , Prognóstico , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: Congenital hypothyroidism is a common, yet easily treatable cause of poor growth and intellectual disability. Newborn screening programs play an important role in the early detection and treatment of congenital hypothyroidism. However, an estimated 71% of children are born in countries such as Ghana, which does not have a screening program. Iodine deficiency, a common cause of congenital hypothyroidism, is present in the Ghanaian population. Mild to moderate maternal iodine deficiency may negatively impact cognitive function in children. A structured approach to examine the association between maternal iodine levels and infant thyroid function may have important ramifications on our understanding of congenital hypothyroidism in Ghana. We investigated the hypothesis that maternal iodine deficiency impacts infant thyroid function, using Thyroid Stimulating Hormone (TSH) as a marker of thyroid function. We also explored potential opportunities and barriers to newborn screening for congenital hypothyroidism in Ghana. METHODS: This was a cross-sectional, multicenter pilot study of 250 women and their neonates recruited from post-natal clinics in Accra and Tamale, Ghana. We compared maternal urine iodine concentration and infant TSH, as well as maternal sociodemographic and nutrition information. Regression models were used to model the relationship between variables. RESULTS: Median infant TSH was 4.7 µIU/ml (95% CI: 3.9-5.5) in Accra. In Tamale, the median infant TSH was 3.5 µIU/ml (95%CI: 3.3 to 3.6) (Δ: 1.3 µIU/ml, 95% CI: 0.5-2.1, p = 0.002). Median maternal urine iodine concentrations were 141.0 µg/L (95% CI: 115.7 to 166.3) and 142.5 µg/L (95% CI: 125.1 to 160.0) in Accra and Tamale, respectively (Δ: - 1.5 µIU/ml, 95% CI: - 32.2 - 29.2, p = 0.925). There was a weakly positive correlation between maternal urine iodine and infant TSH (rho 0.1, p = 0.02). Almost one-third (30%) of women in both locations had biochemical evidence of iodine deficiency. Mothers with any formal education were more likely to have higher iodine levels than their counterparts who had no formal education (coefficient 0.31, p = 0.006). CONCLUSIONS: Maternal iodine deficiency is prevalent in Ghana and is correlated to infant thyroid function. We recommend studies with larger sample sizes to assess the true scope of this relationship.
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Iodo , Criança , Estudos Transversais , Feminino , Gana/epidemiologia , Hospitais , Humanos , Recém-Nascido , Projetos Piloto , Glândula Tireoide , TireotropinaRESUMO
OBJECTIVE: To evaluate the effects of a positive psychology intervention for adolescents with type 1 diabetes (T1D) on adherence, glycemic control, and quality of life. METHODS: Adolescents with T1D (n = 120) and their caregivers were randomized to either an Education (EDU) (n = 60) or Positive Affect (PA) intervention (n = 60). Adolescents in the PA group received the intervention reminders (gratitude, self-affirmation, parental affirmation, and small gifts) via text messages or phone calls over 8 weeks. Questionnaires were completed by adolescents and caregivers and clinical data (glucometer and HbA1c) were collected at baseline 3 and 6 months. Data were analyzed using generalized linear modeling. RESULTS: After adjusting for covariates, adolescents in the PA group demonstrated significant improvement in quality of life at 3 months, compared to the EDU group, but this was not sustained at 6 months. Similarly, the PA group showed a significant decrease in disengagement coping at 3 months but not at 6 months. There was no significant intervention effect on blood glucose monitoring, but the odds of clinically significantly improvement (checking at least one more time/day) were about twice as high in the PA group as the EDU group. No significant effects were found for glycemic control. CONCLUSIONS: A positive psychology intervention had initial significant, positive effects on coping and quality of life in adolescents with T1D. A more intensive or longer-lasting intervention may be needed to sustain these effects and to improve adherence and glycemic control.
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Adaptação Psicológica , Automonitorização da Glicemia/psicologia , Diabetes Mellitus Tipo 1/psicologia , Psicologia Positiva/métodos , Qualidade de Vida/psicologia , Adolescente , Glicemia , Automonitorização da Glicemia/estatística & dados numéricos , Cuidadores , Feminino , Seguimentos , Humanos , Masculino , Avaliação de Resultados da Assistência ao Paciente , Inquéritos e QuestionáriosRESUMO
Epidermal growth factor receptor (EGFR) and its ligands have been implicated in liver fibrosis. However, it has not been directly shown that hepatocellular genetic ablation of either this receptor tyrosine kinase or ERBB3, its interactive signaling partner, affects hepatic fibrosis. Carbon tetrachloride (CCl4)-induced liver fibrosis in hepatocyte-specific (HS) mouse models of EGFR and ERBB3 ablation was evaluated in both single gene knockouts and an HS-EGFR-ERBB3 double knockout (DKO). Loss of hepatocellular EGFR or ERBB3 did not impact cytochrome P450-2E1 expression, the extent of centrilobular injury, or the initial regenerative response, but it did diminish liver fibrosis induced by chronic intraperitoneal administration of CCl4 The reduction of liver fibrosis correlated with reduced α-smooth muscle actin expression. Maximal impact to fibrogenesis occurred in the ERBB3 and EGFR-ERBB3 DKO models, suggesting that EGFR-ERBB3 heterodimeric signaling in damaged hepatocytes may play a more important role in liver fibrosis than EGFR-EGFR homodimeric signaling. Immunohistochemical analyses of phospho-EGFR and phospho-ERBB3 isoforms revealed clear staining in hepatocytes, activated stellate cells, and macrophages. Our results support a role for the hepatocellular ERBB tyrosine kinases in fibrogenesis and suggest that pharmacologic inhibition of EGFR-ERBB3 signaling may reverse or retard hepatic fibrosis.
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Receptores ErbB/metabolismo , Hepatócitos/metabolismo , Cirrose Hepática/metabolismo , Receptor ErbB-3/metabolismo , Animais , Tetracloreto de Carbono , Citocromo P-450 CYP2E1/metabolismo , Receptores ErbB/genética , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Fosforilação , Receptor ErbB-3/genética , Transdução de SinaisRESUMO
The role(s) of the epidermal growth factor receptor (EGFR) in hepatocytes is unknown. We generated a murine hepatocyte specific-EGFR knockout (KO) model to evaluate how loss of hepatocellular EGFR expression affects processes such as EGF clearance, circulating EGF concentrations, and liver regeneration following 70% resection or CCl4-induced centrilobular injury. We were able to disrupt EGFR expression effectively in hepatocytes and showed that the ability of EGF and heregulin (HRG) to phosphorylate EGFR and ERBB3, respectively, required EGFR. Loss of hepatocellular EGFR impaired clearance of exogenous EGF from the portal circulation but paradoxically resulted in reduced circulating levels of endogenous EGF. This was associated with decreased submandibular salivary gland production of EGF. EGFR disruption did not result in increased expression of other ERBB proteins or Met, except in neonatal mice. Liver regeneration following 70% hepatectomy revealed a mild phenotype, with no change in cyclin D1 expression and slight differences in cyclin A expression compared with controls. Peak 5-bromo-2'-deoxyuridine labeling was shifted from 36 to 48 h. Centrilobular damage and regenerative response induced by carbon tetrachloride (CCl4) were identical in the KO and wild-type mice. In contrast, loss of Met increased CCl4-induced necrosis and delayed regeneration. Although loss of hepatocellular EGFR alone did not have an effect in this model, EGFR-Met double KOs displayed enhanced necrosis and delayed liver regeneration compared with Met KOs alone. This suggests that EGFR and Met may partially compensate for the loss of the other, although other compensatory mechanisms can be envisioned.
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Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Receptores ErbB/metabolismo , Hepatócitos/metabolismo , Regeneração Hepática , Proteínas Proto-Oncogênicas c-met/metabolismo , Animais , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Ciclina A/genética , Ciclina A/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/genética , Hepatócitos/fisiologia , Camundongos , Neuregulina-1/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismoRESUMO
Epidermal growth factor receptor (EGFR) and ERBB3 have been implicated in hepatocellular carcinogenesis (HCC). However, it is not known whether altering the activity of either EGFR or ERBB3 affects HCC development. We now show that Egfr(Dsk5) mutant mice, which have a gain-of-function allele that increases basal EGFR kinase activity, develop spontaneous HCC by 10 mo of age. Their tumors show increased activation of EGFR, ERBB2, and ERBB3 as well as AKT and ERK1,2. Hepatocyte-specific models of EGFR and ERBB3 gene ablation were generated to evaluate how the loss of these genes affected tumor progression. Loss of either receptor tyrosine kinase did not alter liver development or regenerative liver growth following carbon tetrachloride injection. However, using a well-characterized model of HCC in which N-nitrosodiethylamine is injected into 14-day-old mice, we discovered that loss of hepatocellular ERBB3 but not EGFR, which occurred after tumor initiation, retarded liver tumor formation and cell proliferation. We found no evidence that this was due to increased apoptosis or diminished phosphatidylinositol-3-kinase activity in the ERBB3-null cells. However, the relative amount of phospho-STAT3 was diminished in tumors derived from these mice, suggesting that ERBB3 may promote HCC through STAT3 activation.
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Transformação Celular Neoplásica/metabolismo , Receptores ErbB/deficiência , Hepatócitos/enzimologia , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/prevenção & controle , Receptor ErbB-3/deficiência , Fatores Etários , Animais , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Dietilnitrosamina , Receptores ErbB/genética , Genótipo , Hepatócitos/patologia , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Regeneração Hepática , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C3H , Camundongos Knockout , Fenótipo , Fosforilação , Receptor ErbB-3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de SinaisRESUMO
Only 21 % of adolescents with type 1 diabetes (T1D) meet glycemic goals set forth by the American Diabetes Association. Adherence to therapy is a particular concern in this population, and the association between poor adherence and worsening glycemic control indicates that there is a critical need to improve adherence to therapy in adolescents with T1D. In this article, we review barriers to adherence in adolescents with T1D and discuss interventions aimed at improving adherence to therapy and glycemic control. Interventions include technology-based applications, family-based therapies, motivational interviewing, and others. Notably, less than 10 % of the interventions reviewed are provider-led, clinic-based interventions, and few have focused on regimen-related aspects of adherence. This article also outlines the importance of provider communication and the role of providers in facilitating adherence behaviors in adolescents with T1D. Finally, we suggest future directions of research to improve adherence to therapy in adolescents with T1D.
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Diabetes Mellitus Tipo 1/terapia , Adolescente , Humanos , Hipoglicemiantes/uso terapêutico , Adesão à Medicação , Entrevista MotivacionalRESUMO
Dsk5 mice have a gain of function in the epidermal growth factor receptor (EGFR), caused by a point mutation in the kinase domain. We analyzed the effect of this mutation on liver size, histology, and composition. We found that the livers of 12-wk-old male Dsk5 heterozygotes (+/Dsk5) were 62% heavier compared with those of wild-type controls (+/+). The livers of the +/Dsk5 mice compared with +/+ mice had larger hepatocytes with prominent, polyploid nuclei and showed modestly increased cell proliferation indices in both hepatocytes and nonparenchymal cells. An analysis of total protein, DNA, and RNA (expressed relative to liver weight) revealed no differences between the mutant and wild-type mice. However, the livers of the +/Dsk5 mice had more cholesterol but less phospholipid and fatty acid. Circulating cholesterol levels were twice as high in adult male +/Dsk5 mice but not in postweaned young male or female mice. The elevated total plasma cholesterol resulted mainly from an increase in low-density lipoprotein (LDL). The +/Dsk5 adult mouse liver expressed markedly reduced protein levels of LDL receptor, no change in proprotein convertase subtilisin/kexin type 9, and a markedly increased fatty acid synthase and 3-hydroxy-3-methyl-glutaryl-CoA reductase. Increased expression of transcription factors associated with enhanced cholesterol synthesis was also observed. Together, these findings suggest that the EGFR may play a regulatory role in hepatocyte proliferation and lipid metabolism in adult male mice, explaining why elevated levels of EGF or EGF-like peptides have been positively correlated to increased cholesterol levels in human studies.
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Receptores ErbB/metabolismo , Metabolismo dos Lipídeos/fisiologia , Lipídeos/sangue , Fígado/metabolismo , Tecido Adiposo/anatomia & histologia , Alelos , Animais , Sulfatos de Condroitina , Dermatan Sulfato , Receptores ErbB/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Heparitina Sulfato , Rim/anatomia & histologia , Fígado/anatomia & histologia , Masculino , Camundongos , Sarcoma de Células Pequenas , Transdução de Sinais , Baço/anatomia & histologia , Testículo/anatomia & histologiaRESUMO
OBJECTIVE: Mixed-meal tolerance test-stimulated area under the curve (AUC) C-peptide at 12-24 months represents the primary end point for nearly all intervention trials seeking to preserve ß-cell function in recent-onset type 1 diabetes. We hypothesized that participant benefit might be detected earlier and predict outcomes at 12 months posttherapy. Such findings would support shorter trials to establish initial efficacy. RESEARCH DESIGN AND METHODS: We examined data from six Type 1 Diabetes TrialNet immunotherapy randomized controlled trials in a post hoc analysis and included additional stimulated metabolic indices beyond C-peptide AUC. We partitioned the analysis into successful and unsuccessful trials and analyzed the data both in the aggregate as well as individually for each trial. RESULTS: Among trials meeting their primary end point, we identified a treatment effect at 3 and 6 months when using C-peptide AUC (P = 0.030 and P < 0.001, respectively) as a dynamic measure (i.e., change from baseline). Importantly, no such difference was seen in the unsuccessful trials. The use of C-peptide AUC as a 6-month dynamic measure not only detected treatment efficacy but also suggested long-term C-peptide preservation (R2 for 12-month C-peptide AUC adjusted for age and baseline value was 0.80, P < 0.001), and this finding supported the concept of smaller trial sizes down to 54 participants. CONCLUSIONS: Early dynamic measures can identify a treatment effect among successful immune therapies in type 1 diabetes trials with good long-term prediction and practical sample size over a 6-month period. While external validation of these findings is required, strong rationale and data exist in support of shortening early-phase clinical trials.
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Peptídeo C , Diabetes Mellitus Tipo 1 , Imunoterapia , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Humanos , Peptídeo C/sangue , Peptídeo C/metabolismo , Imunoterapia/métodos , Feminino , Masculino , Adolescente , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Criança , Adulto , Área Sob a CurvaRESUMO
OBJECTIVE: This multicenter prospective cohort study compared pancreas volume as assessed by MRI, metabolic scores derived from oral glucose tolerance testing (OGTT), and a combination of pancreas volume and metabolic scores for predicting progression to stage 3 type 1 diabetes (T1D) in individuals with multiple diabetes-related autoantibodies. RESEARCH DESIGN AND METHODS: Pancreas MRI was performed in 65 multiple autoantibody-positive participants enrolled in the Type 1 Diabetes TrialNet Pathway to Prevention study. Prediction of progression to stage 3 T1D was assessed using pancreas volume index (PVI), OGTT-derived Index60 score and Diabetes Prevention Trial-Type 1 Risk Score (DPTRS), and a combination of PVI and DPTRS. RESULTS: PVI, Index60, and DPTRS were all significantly different at study entry in 11 individuals who subsequently experienced progression to stage 3 T1D compared with 54 participants who did not experience progression (P < 0.005). PVI did not correlate with metabolic testing across individual study participants. PVI declined longitudinally in the 11 individuals diagnosed with stage 3 T1D, whereas Index60 and DPTRS increased. The area under the receiver operating characteristic curve for predicting progression to stage 3 from measurements at study entry was 0.76 for PVI, 0.79 for Index60, 0.79 for DPTRS, and 0.91 for PVI plus DPTRS. CONCLUSIONS: These findings suggest that measures of pancreas volume and metabolism reflect distinct components of risk for developing stage 3 type 1 diabetes and that a combination of these measures may provide superior prediction than either alone.
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Diabetes Mellitus Tipo 1 , Humanos , Diabetes Mellitus Tipo 1/diagnóstico , Estudos Prospectivos , Pâncreas/diagnóstico por imagem , Pâncreas/metabolismo , Fatores de Risco , Autoanticorpos , Imageamento por Ressonância MagnéticaRESUMO
Context: Participants with stage 1 or 2 type 1 diabetes (T1D) qualify for prevention trials, but factors involved in screening for such trials are largely unknown. Objective: To identify factors associated with screening for T1D prevention trials. Methods: This study included TrialNet Pathway to Prevention participants who were eligible for a prevention trial: oral insulin (TN-07, TN-20), teplizumab (TN-10), abatacept (TN-18), and oral hydroxychloroquine (TN-22). Univariate and multivariate logistic regression models were used to examine participant, site, and study factors at the time of prevention trial accrual. Results: Screening rates for trials were: 50% for TN-07 (584 screened/1172 eligible), 9% for TN-10 (106/1249), 24% for TN-18 (313/1285), 17% for TN-20 (113/667), and 28% for TN-22 (371/1336). Younger age and male sex were associated with higher screening rates for prevention trials overall and for oral therapies. Participants with an offspring with T1D showed lower rates of screening for all trials and oral drug trials compared with participants with other first-degree relatives as probands. Site factors, including larger monitoring volume and US site vs international site, were associated with higher prevention trial screening rates. Conclusions: Clear differences exist between participants who screen for prevention trials and those who do not screen and between the research sites involved in prevention trial screening. Participant age, sex, and relationship to proband are significantly associated with prevention trial screening in addition to key site factors. Identifying these factors can facilitate strategic recruitment planning to support rapid and successful enrollment into prevention trials.
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OBJECTIVE: Previous studies showed that inhibiting lymphocyte costimulation reduces declining ß-cell function in individuals newly diagnosed with type 1 diabetes. We tested whether abatacept would delay or prevent progression of type 1 diabetes from normal glucose tolerance (NGT) to abnormal glucose tolerance (AGT) or to diabetes and the effects of treatment on immune and metabolic responses. RESEARCH DESIGN AND METHODS: We conducted a phase 2, randomized, placebo-controlled, double-masked trial of abatacept in antibody-positive participants with NGT who received monthly abatacept/placebo infusions for 12 months. The end point was AGT or diabetes, assessed by oral glucose tolerance tests. RESULTS: A total of 101 participants received abatacept and 111 placebo. Of these, 81 (35 abatacept and 46 placebo) met the end point of AGT or type 1 diabetes diagnosis (hazard ratio 0.702; 95% CI 0.452, 1.09; P = 0.11) The C-peptide responses to oral glucose tolerance tests were higher in the abatacept arm (P < 0.03). Abatacept reduced the frequency of inducible T-cell costimulatory (ICOS)+ PD1+ T-follicular helper (Tfh) cells during treatment (P < 0.0001), increased naive CD4+ T cells, and also reduced the frequency of CD4+ regulatory T cells (Tregs) from the baseline (P = 0.0067). Twelve months after treatment, the frequency of ICOS+ Tfh, naive CD4+ T cells, and Tregs returned to baseline. CONCLUSIONS: Although abatacept treatment for 1 year did not significantly delay progression to glucose intolerance in at-risk individuals, it impacted immune cell subsets and preserved insulin secretion, suggesting that costimulation blockade may modify progression of type 1 diabetes.
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Diabetes Mellitus Tipo 1 , Humanos , Abatacepte/uso terapêutico , Abatacepte/farmacologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Imunossupressores , Linfócitos T Reguladores , Glucose/uso terapêuticoRESUMO
BACKGROUND: The immunopathogenesis of type 1 diabetes mellitus is associated with T-cell autoimmunity. To be fully active, immune T cells need a co-stimulatory signal in addition to the main antigen-driven signal. Abatacept modulates co-stimulation and prevents full T-cell activation. We evaluated the effect of abatacept in recent-onset type 1 diabetes. METHODS: In this multicentre, double-blind, randomised controlled trial, patients aged 6-45 years recently diagnosed with type 1 diabetes were randomly assigned (2:1) to receive abatacept (10 mg/kg, maximum 1000 mg per dose) or placebo infusions intravenously on days 1, 14, 28, and monthly for a total of 27 infusions over 2 years. Computer-generated permuted block randomisation was used, with a block size of 3 and stratified by participating site. Neither patients nor research personnel were aware of treatment assignments. The primary outcome was baseline-adjusted geometric mean 2-h area-under-the-curve (AUC) serum C-peptide concentration after a mixed-meal tolerance test at 2 years' follow-up. Analysis was by intention to treat for all patients for whom data were available. This trial is registered at ClinicalTrials.gov, NCT00505375. FINDINGS: 112 patients were assigned to treatment groups (77 abatacept, 35 placebo). Adjusted C-peptide AUC was 59% (95% CI 6·1-112) higher at 2 years with abatacept (n=73, 0·378 nmol/L) than with placebo (n=30, 0·238 nmol/L; p=0·0029). The difference between groups was present throughout the trial, with an estimated 9·6 months' delay (95% CI 3·47-15·6) in C-peptide reduction with abatacept. There were few infusion-related adverse events (36 reactions occurred in 17 [22%] patients on abatacept and 11 reactions in six [17%] on placebo). There was no increase in infections (32 [42%] patients on abatacept vs 15 [43%] on placebo) or neutropenia (seven [9%] vs five [14%]). INTERPRETATION: Co-stimulation modulation with abatacept slowed reduction in ß-cell function over 2 years. The beneficial effect suggests that T-cell activation still occurs around the time of clinical diagnosis of type 1 diabetes. Yet, despite continued administration of abatacept over 24 months, the decrease in ß-cell function with abatacept was parallel to that with placebo after 6 months of treatment, causing us to speculate that T-cell activation lessens with time. Further observation will establish whether the beneficial effect continues after cessation of abatacept infusions. FUNDING: US National Institutes of Health.
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Diabetes Mellitus Tipo 1/tratamento farmacológico , Imunoconjugados/uso terapêutico , Imunossupressores/uso terapêutico , Abatacepte , Adolescente , Adulto , Autoimunidade , Criança , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Imunoconjugados/efeitos adversos , Imunoconjugados/imunologia , Imunossupressores/efeitos adversos , Células Secretoras de Insulina/fisiologia , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Linfócitos T/imunologia , Adulto JovemRESUMO
BackgroundIL-6 receptor (IL-6R) signaling drives development of T cell populations important to type 1 diabetes pathogenesis. We evaluated whether blockade of IL-6R with monoclonal antibody tocilizumab would slow loss of residual ß cell function in newly diagnosed type 1 diabetes patients.MethodsWe conducted a multicenter, randomized, placebo-controlled, double-blind trial with tocilizumab in new-onset type 1 diabetes. Participants were screened within 100 days of diagnosis. Eligible participants were randomized 2:1 to receive 7 monthly doses of tocilizumab or placebo. The primary outcome was the change from screening in the mean AUC of C-peptide collected during the first 2 hours of a mixed meal tolerance test at week 52 in pediatric participants (ages 6-17 years).ResultsThere was no statistical difference in the primary outcome between tocilizumab and placebo. Immunophenotyping showed reductions in downstream signaling of the IL-6R in T cells but no changes in CD4 memory subsets, Th17 cells, Tregs, or CD4+ T effector cell resistance to Treg suppression. A DC subset decreased during therapy but regressed to baseline once therapy stopped. Tocilizumab was well tolerated.ConclusionTocilizumab reduced T cell IL-6R signaling but did not modulate CD4+ T cell phenotypes or slow loss of residual ß cell function in newly diagnosed individuals with type 1 diabetes.Trial RegistrationClinicalTrials.gov NCT02293837.FundingNIH National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and National Institute of Allergy and Infectious Diseases (NIAID) UM1AI109565, UL1TR000004 from NIH/National Center for Research Resources (NCRR) Clinical and Translational Science Award (CTSA), NIH/NIDDK P30DK036836, NIH/NIDDK U01DK103266, NIH/NIDDK U01DK103266, 1UL1TR000064 from NIH/NCRR CTSA, NIH/National Center for Advancing Translational Sciences (NCATS) UL1TR001878, UL1TR002537 from NIH/CTSA; National Health and Medical Research Council Practitioner Fellowship (APP1136735), NIH/NIDDK U01-DK085476, NIH/CTSA UL1-TR002494, Indiana Clinical and Translational Science Institute Award UL1TR002529, Vanderbilt Institute for Clinical and Translational Research UL1TR000445. NIH/NCATS UL1TR003142, NIH/CTSA program UL1-TR002494, Veteran Affairs Administration, and 1R01AI132774.
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Subpopulações de Linfócitos B/metabolismo , Diabetes Mellitus Tipo 1/genética , Receptores de Interleucina-6/antagonistas & inibidores , Adolescente , Criança , Diabetes Mellitus Tipo 1/patologia , Método Duplo-Cego , Feminino , Humanos , MasculinoRESUMO
The G6Pase (glucose-6-phosphatase catalytic subunit) catalyses the final step in the gluconeogenic and glycogenolytic pathways, the hydrolysis of glucose-6-phosphate to glucose. We show here that, in HepG2 hepatoma cells, EGF (epidermal growth factor) inhibits basal mouse G6Pase fusion gene transcription. Several studies have shown that insulin represses basal mouse G6Pase fusion gene transcription through FOXO1 (forkhead box O1), but Stoffel and colleagues have recently suggested that insulin can also regulate gene transcription through FOXA2 (forkhead box A2) [Wolfrum, Asilmaz, Luca, Friedman and Stoffel (2003) Proc. Natl. Acad. Sci. 100, 11624-11629]. A combined GR (glucocorticoid receptor)-FOXA2 binding site is located between -185 and -174 in the mouse G6Pase promoter overlapping two FOXO1 binding sites located between (-188 and -182) and (-174 and -168). Selective mutation of the FOXO1 binding sites reduced the effect of insulin, whereas mutation of the GR/FOXA2 binding site had no effect on the insulin response. In contrast, selective mutation of the FOXO1 and GR/FOXA2 binding sites both reduced the effect of EGF. The effect of these mutations was additive, since the combined mutation of both FOXO1 and GR/FOXA2 binding sites reduced the effect of EGF to a greater extent than the individual mutations. These results suggest that, in HepG2 cells, GR and/or FOXA2 are required for the inhibition of basal G6Pase gene transcription by EGF but not insulin. EGF also inhibits hepatic G6Pase gene expression in vivo, but in cultured hepatocytes EGF has the opposite effect of stimulating expression, an observation that may be explained by a switch in ErbB receptor sub-type expression following hepatocyte isolation.
Assuntos
Biocatálise , Fator de Crescimento Epidérmico/farmacologia , Glucose-6-Fosfatase/metabolismo , Insulina/farmacologia , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , Animais , Sítios de Ligação , Células Cultivadas , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucose-6-Fosfatase/genética , Fator 1 Nuclear de Hepatócito/metabolismo , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Fator 3-beta Nuclear de Hepatócito/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Mutação/genética , Regiões Promotoras Genéticas/genética , Subunidades Proteicas/metabolismo , RatosRESUMO
Reduced pancreas volume, as measured by non-contrast magnetic resonance imaging (MRI), is observed in individuals with newly-diagnosed type 1 diabetes (T1D) and declines over the first year after diagnosis. In this study, we determined the repeatability and inter-reader reproducibility of pancreas volume measurements by MRI. Test-retest scans in individuals with or without T1D (n = 16) had an intraclass correlation coefficient (ICC) of 0.985 (95% CI 0.961 to 0.995) for pancreas volume. Independent pancreas outlines by two board-certified radiologists (n = 30) yielded an ICC of 0.945 (95% CI 0.889 to 0.973). The mean Dice coefficient, a measurement of the degree of overlap between pancreas regions of interest between the two readers, was 0.77. Prandial state did not influence pancreatic measurements, as stomach volume did not correlate with pancreas volume. These data demonstrate that MRI measurements of pancreas volume between two readers are repeatable and reproducible with ICCs that correspond to excellent clinical significance (ICC > 0.9), are not related to changes in stomach volume, and could be a useful tool for clinical investigation of diabetes and other pancreas pathologies.
Assuntos
Diabetes Mellitus Tipo 1/diagnóstico por imagem , Diabetes Mellitus Tipo 1/patologia , Imageamento por Ressonância Magnética/métodos , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Tamanho do Órgão , Reprodutibilidade dos Testes , Adulto JovemRESUMO
OBJECTIVE: This study investigated the temporal dynamics of pancreas volume and microstructure in children and adolescents with recent-onset type 1 diabetes (T1D) and individuals without diabetes, including a subset expressing autoantibodies associated with the early stages of T1D. RESEARCH DESIGN AND METHODS: MRI was performed in individuals with recent-onset stage 3 T1D (n = 51; median age 13 years) within 100 days after diagnosis (mean 67 days), 6 months, and 1 year postdiagnosis. Longitudinal MRI measurements were also made in similarly aged control participants (n = 57) and in autoantibody-positive individuals without diabetes (n = 20). The MRI protocol consisted of anatomical imaging to determine pancreas volume and quantitative MRI protocols interrogating tissue microstructure and composition. RESULTS: Within 100 days of diabetes onset, individuals with T1D had a smaller pancreas (median volume 28.6 mL) than control participants (median volume 48.4 mL; P < 0.001), including when normalized by individual weight (P < 0.001). Longitudinal measurements of pancreas volume increased in control participants over the year, consistent with adolescent growth, but pancreas volume declined over the first year after T1D diagnosis (P < 0.001). In multiple autoantibody-positive individuals, the pancreas volume was significantly larger than that of the T1D cohort (P = 0.017) but smaller than that of the control cohort (P = 0.04). Diffusion-weighted MRI showed that individuals with recent-onset T1D had a higher apparent diffusion coefficient (P = 0.012), suggesting a loss of cellular structural integrity, with heterogeneous pancreatic distribution. CONCLUSIONS: These results indicate that pancreas volume is decreased in stages 1, 2, and 3 of T1D and decreases during the first year after diabetes onset and that this loss of pancreatic volume is accompanied by microstructural changes.
Assuntos
Diabetes Mellitus Tipo 1/diagnóstico , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Adolescente , Adulto , Atrofia/diagnóstico , Atrofia/etiologia , Autoanticorpos/análise , Autoanticorpos/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/patologia , Feminino , Teste de Tolerância a Glucose , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Pâncreas/ultraestrutura , Fatores de Tempo , Adulto JovemRESUMO
A three-arm, randomized, double-masked, placebo-controlled phase 2b trial performed by the Type 1 Diabetes TrialNet Study Group previously demonstrated that low-dose anti-thymocyte globulin (ATG) (2.5 mg/kg) preserved ß-cell function and reduced HbA1c for 1 year in new-onset type 1 diabetes. Subjects (N = 89) were randomized to 1) ATG and pegylated granulocyte colony-stimulating factor (GCSF), 2) ATG alone, or 3) placebo. Herein, we report 2-year area under the curve (AUC) C-peptide and HbA1c, prespecified secondary end points, and potential immunologic correlates. The 2-year mean mixed-meal tolerance test-stimulated AUC C-peptide, analyzed by ANCOVA adjusting for baseline C-peptide, age, and sex (n = 82) with significance defined as one-sided P < 0.025, was significantly higher in subjects treated with ATG versus placebo (P = 0.00005) but not ATG/GCSF versus placebo (P = 0.032). HbA1c was significantly reduced at 2 years in subjects treated with ATG (P = 0.011) and ATG/GCSF (P = 0.022) versus placebo. Flow cytometry analyses demonstrated reduced circulating CD4:CD8 ratio, increased regulatory T-cell:conventional CD4 T-cell ratios, and increased PD-1+CD4+ T cells following low-dose ATG and ATG/GCSF. Low-dose ATG partially preserved ß-cell function and reduced HbA1c 2 years after therapy in new-onset type 1 diabetes. Future studies should determine whether low-dose ATG might prevent or delay the onset of type 1 diabetes.
Assuntos
Soro Antilinfocitário/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Adolescente , Adulto , Peptídeo C/metabolismo , Relação CD4-CD8 , Criança , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Método Duplo-Cego , Feminino , Citometria de Fluxo , Hemoglobinas Glicadas/metabolismo , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Masculino , Linfócitos T Reguladores/imunologia , Adulto JovemRESUMO
We investigated for evidence of early metabolic syndrome irrespective of body mass index (BMI) in subjects with premature pubarche (PP). Ten children with PP were compared with controls matched for age, sex, ethnicity, and BMI. Congenital adrenal hyperplasia and other known causes of PP were excluded by standard methods. Anthropometry, blood pressure (BP), dual-energy x-ray absorptiometry body scan, fasting blood lipid profile, and cytokines were obtained. The children were divided into 2 groups: (1) the total group of children with PP, and their age-, sex-, ethnicity-, and BMI-matched controls and (2) those with PP and normal BMI (<19 kg/m(2)) and their matched controls selected from the original groups. The PP subjects with normal BMI (S(1)) showed significantly higher systolic BP (P = .028), diastolic BP (P = .028), and mean arterial pressure (P = .018) compared with matched controls (C(1)). Nevertheless, for both groups, all the above parameters were statistically not significant when corrected for height. Fat distribution in PP subjects indicated significantly higher android (P = .047) and android-gynoid ratio (P = .013). Normal-BMI PP children had significantly higher android-gynoid ratio fat distribution compared with their matched controls (P = .037). Trunk fat percentage (p: 0.04) and trunk fat (grams) (P = .007) were significantly elevated in PP children compared with matched controls. Again, for both groups, all the above parameters were not statistically significant when corrected for height. The PP subjects had significantly higher tumor necrosis factor (TNF)-alpha (P = .038) and interleukin-8 (picograms per milliliter) (P = .05) compared with matched controls. Normal-BMI PP children also had higher TNF-alpha (P = .028) compared with matched controls. When corrected for height, TNF-alpha was higher in the total (P = .037) and normal-BMI (P = .043) PP children. Premature pubarche can be linked to markers of the metabolic syndrome in lean children.