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1.
Commun Med (Lond) ; 4(1): 66, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582818

RESUMO

BACKGROUND: Islet autoantibodies form the foundation for type 1 diabetes (T1D) diagnosis and staging, but heterogeneity exists in T1D development and presentation. We hypothesized that autoantibodies can identify heterogeneity before, at, and after T1D diagnosis, and in response to disease-modifying therapies. METHODS: We systematically reviewed PubMed and EMBASE databases (6/14/2022) assessing 10 years of original research examining relationships between autoantibodies and heterogeneity before, at, after diagnosis, and in response to disease-modifying therapies in individuals at-risk or within 1 year of T1D diagnosis. A critical appraisal checklist tool for cohort studies was modified and used for risk of bias assessment. RESULTS: Here we show that 152 studies that met extraction criteria most commonly characterized heterogeneity before diagnosis (91/152). Autoantibody type/target was most frequently examined, followed by autoantibody number. Recurring themes included correlations of autoantibody number, type, and titers with progression, differing phenotypes based on order of autoantibody seroconversion, and interactions with age and genetics. Only 44% specifically described autoantibody assay standardization program participation. CONCLUSIONS: Current evidence most strongly supports the application of autoantibody features to more precisely define T1D before diagnosis. Our findings support continued use of pre-clinical staging paradigms based on autoantibody number and suggest that additional autoantibody features, particularly in relation to age and genetic risk, could offer more precise stratification. To improve reproducibility and applicability of autoantibody-based precision medicine in T1D, we propose a methods checklist for islet autoantibody-based manuscripts which includes use of precision medicine MeSH terms and participation in autoantibody standardization workshops.


Islet autoantibodies are markers found in the blood when insulin-producing cells in the pancreas become damaged and can be used to predict future development of type 1 diabetes. We evaluated published literature to determine whether characteristics of islet antibodies (type, levels, numbers) could improve prediction and help understand differences in how individuals with type 1 diabetes respond to treatments. We found existing evidence shows that islet autoantibody type and number are most useful to predict disease progression before diagnosis. In addition, the age when islet autoantibodies first appear strongly influences rate of progression. These findings provide important information for patients and care providers on how islet autoantibodies can be used to understand future type 1 diabetes development and to identify individuals who have the potential to benefit from intervention or prevention therapy.

2.
Horm Res Paediatr ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663372

RESUMO

Teplizumab (TzieldTM, Provention Bio), a monoclonal antibody directed at t-cell marker CD3, is the first medication approved by the FDA to delay progression from Stage 2 to Stage 3 type 1 diabetes (T1D). To date, the overwhelming majority of pediatric endocrinologists do not have experience using immunotherapeutics and seek guidance the use of teplizumab in clinical practice. To address this need, the Pediatric Endocrine Society (PES) Diabetes Special Interest Group (Diabetes SIG) and Drug and Therapeutics Committee assembled a task force to review clinical trial data and solicit expert recommendations on the approach to teplizumab infusions. We present considerations on all aspects of teplizumab administration, utilizing evidence where possible and providing a spectrum of expert opinions on unknown aspects. We discuss patient selection and prescreening, highlighting the safety and considerations for monitoring and treatment of side effects. We propose a schedule of events, a protocol for administration and discuss practice management aspects. We advocate for the need for further long-term systematic surveillance studies to continue evaluating the efficacy and safety of teplizumab.

3.
bioRxiv ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38659945

RESUMO

ß cell extracellular vesicles (EVs) play a role as paracrine effectors in islet health, yet mechanisms connecting ß cell stress to changes in EV cargo and potential impacts on diabetes remain poorly defined. We hypothesized that ß cell inflammatory stress engages neutral sphingomyelinase 2 (nSMase2)-dependent EV formation pathways, generating ceramide-enriched EVs that could impact surrounding ß cells. Consistent with this, proinflammatory cytokine treatment of INS-1 ß cells and human islets concurrently increased ß cell nSMase2 and ceramide expression, as well as EV ceramide staining. Direct chemical activation or genetic knockdown of nSMase2, or treatment with a GLP-1 receptor agonist also modulated cellular and EV ceramide. Small RNA sequencing of ceramide-enriched EVs identified a distinct set of miRNAs linked to ß cell function and identity. Coculture experiments using CD9-GFP tagged INS-1 cell EVs demonstrated that either cytokine treatment or chemical nSMase2 activation increased EV transfer to recipient cells. Children with recent-onset T1D showed no abnormalities in circulating ceramide-enriched EVs, suggesting a localized, rather than systemic phenomenon. These findings highlight nSMase2 as a regulator of ß cell EV cargo and identify ceramide-enriched EV populations as a contributor to EV-related paracrine signaling under conditions of ß cell inflammatory stress. Article Highlights: a. Why did we undertake this study?: Mechanisms connecting ß cell stress to changes in extracellular vesicle (EV) cargo and potential impacts on diabetes are poorly defined.b. What is the specific question we wanted to answer?: Does ß cell inflammatory stress engage neutral sphingomyelinase 2 (nSMase2)-dependent EV formation pathways to generate ceramide-enriched EVs.c. What did we find?: Proinflammatory cytokine treatment of ß cells increased ß cell ceramide expression, along with EV ceramide in part via increases in nSMase2. Ceramide-enriched EVs housed a distinct set of miRNAs linked to insulin signaling. Both cytokine treatment and nSMase2 activation increase EV transfer to other ß cells.d. What are the implications of our findings?: Our findings highlight nSMase2 as a regulator of ß cell EV cargo and identify ceramide-enriched EV populations as a contributor to EV-related paracrine signaling under conditions of ß cell inflammatory stress.

4.
Diabetes Care ; 47(6): 1048-1055, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38621411

RESUMO

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.


Assuntos
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 Curva
5.
Artigo em Inglês | MEDLINE | ID: mdl-38267821

RESUMO

CONTEXT: Metabolic measures are frequently used to predict T1D and to understand effects of disease-modifying therapies. OBJECTIVE: Compare metabolic endpoints for their ability to detect preventive treatment effects and predict T1D. DESIGN: Six-month changes in metabolic endpoints were assessed for: 1) detecting treatment effects by comparing placebo and treatment arms from the randomized controlled teplizumab prevention trial and 2) predicting T1D in the TrialNet Pathway to Prevention natural history study. SETTING: Multicenter clinical trial network. INTERVENTION: 14-day intravenous teplizumab infusion. MAIN OUTCOME MEASURES: T-values from t tests for detecting a treatment effect were compared to Chi-square values from proportional hazards regression for predicting T1D for each metabolic measure. PATIENTS OR OTHER PARTICIPANTS: Participants in the teplizumab prevention trial and participants in the Pathway to Prevention study selected with the same inclusion criteria used for the teplizumab trial were studied. RESULTS: Six-month changes in glucose-based endpoints predicted diabetes better than C-peptide-based endpoints, yet the latter were better at detecting a teplizumab effect. Combined measures of glucose and C-peptide were more balanced than measures of glucose alone or C-peptide alone for predicting diabetes and detecting a teplizumab effect. CONCLUSIONS: The capacity of a metabolic endpoint to detect a treatment effect does not necessarily correspond to its accuracy for predicting T1D. However, combined glucose and C-peptide endpoints appear to be effective for both predicting diabetes and detecting a response to immunotherapy. These findings suggest that combined glucose and C-peptide endpoints should be incorporated into the design of future T1D prevention trials.

7.
Sci Data ; 10(1): 837, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017024

RESUMO

Extracellular vesicles play major roles in cell-to-cell communication and are excellent biomarker candidates. However, studying plasma extracellular vesicles is challenging due to contaminants. Here, we performed a proteomics meta-analysis of public data to refine the plasma EV composition by separating EV proteins and contaminants into different clusters. We obtained two clusters with a total of 1717 proteins that were depleted of known contaminants and enriched in EV markers with independently validated 71% true-positive. These clusters had 133 clusters of differentiation (CD) antigens and were enriched with proteins from cell-to-cell communication and signaling. We compared our data with the proteins deposited in PeptideAtlas, making our refined EV protein list a resource for mechanistic and biomarker studies. As a use case example for this resource, we validated the type 1 diabetes biomarker proplatelet basic protein in EVs and showed that it regulates apoptosis of ß cells and macrophages, two key players in the disease development. Our approach provides a refinement of the EV composition and a resource for the scientific community.


Assuntos
Vesículas Extracelulares , Proteômica , Antígenos CD/metabolismo , Biomarcadores , Vesículas Extracelulares/metabolismo , Proteínas , Transdução de Sinais , Conjuntos de Dados como Assunto , Humanos , Animais
8.
Cell Rep Med ; 4(11): 101261, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37918404

RESUMO

In preclinical models, α-difluoromethylornithine (DFMO), an ornithine decarboxylase (ODC) inhibitor, delays the onset of type 1 diabetes (T1D) by reducing ß cell stress. However, the mechanism of DFMO action and its human tolerability remain unclear. In this study, we show that mice with ß cell ODC deletion are protected against toxin-induced diabetes, suggesting a cell-autonomous role of ODC during ß cell stress. In a randomized controlled trial (ClinicalTrials.gov: NCT02384889) involving 41 recent-onset T1D subjects (3:1 drug:placebo) over a 3-month treatment period with a 3-month follow-up, DFMO (125-1,000 mg/m2) is shown to meet its primary outcome of safety and tolerability. DFMO dose-dependently reduces urinary putrescine levels and, at higher doses, preserves C-peptide area under the curve without apparent immunomodulation. Transcriptomics and proteomics of DFMO-treated human islets exposed to cytokine stress reveal alterations in mRNA translation, nascent protein transport, and protein secretion. These findings suggest that DFMO may preserve ß cell function in T1D through islet cell-autonomous effects.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Camundongos , Animais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Ornitina Descarboxilase/genética , Ornitina Descarboxilase/metabolismo , Inibidores da Ornitina Descarboxilase/farmacologia , Eflornitina/farmacologia , Eflornitina/uso terapêutico , Putrescina/metabolismo
9.
Islets ; 15(1): 2267725, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-37838950

RESUMO

The pancreatic ß cell synthesizes, packages, and secretes insulin in response to glucose-stimulation to maintain blood glucose homeostasis. Under diabetic conditions, a subset of ß cells fail and lose expression of key transcription factors (TFs) required for insulin secretion. Among these TFs is Pancreatic and duodenal homeobox 1 (PDX1), which recruits a unique subset of transcriptional coregulators to modulate its activity. Here we describe a novel interacting partner of PDX1, the Staphylococcal Nuclease and Tudor domain-containing protein (SND1), which has been shown to facilitate protein-protein interactions and transcriptional control through diverse mechanisms in a variety of tissues. PDX1:SND1 interactions were confirmed in rodent ß cell lines, mouse islets, and human islets. Utilizing CRISPR-Cas9 gene editing technology, we deleted Snd1 from the mouse ß cell lines, which revealed numerous differentially expressed genes linked to insulin secretion and cell proliferation, including limited expression of Glp1r. We observed Snd1 deficient ß cell lines had reduced cell expansion rates, GLP1R protein levels, and limited cAMP accumulation under stimulatory conditions, and further show that acute ablation of Snd1 impaired insulin secretion in rodent and human ß cell lines. Lastly, we discovered that PDX1:SND1 interactions were profoundly reduced in human ß cells from donors with type 2 diabetes (T2D). These observations suggest the PDX1:SND1 complex formation is critical for controlling a subset of genes important for ß cell function and is targeted in diabetes pathogenesis.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Animais , Humanos , Camundongos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Expressão Gênica , Regulação da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Domínio Tudor
10.
Commun Med (Lond) ; 3(1): 130, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37794169

RESUMO

BACKGROUND: Type 1 diabetes (T1D) results from immune-mediated destruction of insulin-producing beta cells. Prevention efforts have focused on immune modulation and supporting beta cell health before or around diagnosis; however, heterogeneity in disease progression and therapy response has limited translation to clinical practice, highlighting the need for precision medicine approaches to T1D disease modification. METHODS: To understand the state of knowledge in this area, we performed a systematic review of randomized-controlled trials with ≥50 participants cataloged in PubMed or Embase from the past 25 years testing T1D disease-modifying therapies and/or identifying features linked to treatment response, analyzing bias using a Cochrane-risk-of-bias instrument. RESULTS: We identify and summarize 75 manuscripts, 15 describing 11 prevention trials for individuals with increased risk for T1D, and 60 describing treatments aimed at preventing beta cell loss at disease onset. Seventeen interventions, mostly immunotherapies, show benefit compared to placebo (only two prior to T1D onset). Fifty-seven studies employ precision analyses to assess features linked to treatment response. Age, beta cell function measures, and immune phenotypes are most frequently tested. However, analyses are typically not prespecified, with inconsistent methods of reporting, and tend to report positive findings. CONCLUSIONS: While the quality of prevention and intervention trials is overall high, the low quality of precision analyses makes it difficult to draw meaningful conclusions that inform clinical practice. To facilitate precision medicine approaches to T1D prevention, considerations for future precision studies include the incorporation of uniform outcome measures, reproducible biomarkers, and prespecified, fully powered precision analyses into future trial design.


Type 1 diabetes (T1D) is a condition that results from the destruction of a type of cell in the pancreas that produces the hormone insulin, leading to lifelong dependence on insulin injections. T1D prevention remains a challenging goal, largely due to the immense variability in disease processes and progression. Therapies tested to date in medical research settings (clinical trials) work only in a subset of individuals, highlighting the need for more tailored prevention approaches. We reviewed clinical trials of therapies targeting the disease process in T1D. While the overall quality of trials was high, studies testing individual features affecting responses to treatments were low. This review reveals an important need to carefully plan high-quality analyses of features that affect treatment response in T1D, to ensure that tailored approaches may one day be applied to clinical practice.

11.
Diabetologia ; 66(12): 2283-2291, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37667106

RESUMO

AIMS/HYPOTHESIS: Tractable precision biomarkers to identify immunotherapy responders are lacking in type 1 diabetes. We hypothesised that proinsulin:C-peptide (PI:C) ratios, a readout of beta cell stress, could provide insight into type 1 diabetes progression and responses to immunotherapy. METHODS: In this post hoc analysis, proinsulin and C-peptide levels were determined in baseline serum samples from 63 participants with stage 2 type 1 diabetes in the longitudinal TrialNet Teplizumab Prevention Study (n=41 in the teplizumab arm; n=22 in the placebo arm). In addition, previously tested demographic, C-peptide, glucose and proinsulin data were used for the new data analyses. The ratio of intact (unprocessed) proinsulin to C-peptide was analysed and relationships with progression to stage 3 diabetes were investigated. RESULTS: Elevated baseline PI:C was strongly associated with more rapid progression of diabetes in both the placebo and teplizumab treatment groups, but teplizumab abrogated the impact of high pre-treatment PI:C on type 1 diabetes progression. Differential responses of drug treatment in those with high vs low PI:C ratios were independent of treatment effects of teplizumab on the PI:C ratio or on relevant immune cells. CONCLUSIONS/INTERPRETATION: High pre-treatment PI:C identified individuals with stage 2 type 1 diabetes who were exhibiting rapid progression to stage 3 disease and who displayed benefit from teplizumab treatment. These data suggest that readouts of active disease, such as PI:C ratio, could serve to identify optimal candidates or timing for type 1 diabetes disease-modifying therapies.


Assuntos
Diabetes Mellitus Tipo 1 , Proinsulina , Humanos , Peptídeo C , Anticorpos Monoclonais Humanizados/uso terapêutico , Insulina/metabolismo
12.
J Clin Endocrinol Metab ; 108(12): 3067-3079, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37290044

RESUMO

A diagnosis of type 1 diabetes (T1D) and the subsequent requirement for exogenous insulin treatment is associated with considerable acute and chronic morbidity and a substantial effect on patient quality of life. Importantly, a large body of work suggests that early identification of presymptomatic T1D can accurately predict clinical disease, and when paired with education and monitoring, can yield improved health outcomes. Furthermore, a growing cadre of effective disease-modifying therapies provides the potential to alter the natural history of early stages of T1D. In this mini review, we highlight prior work that has led to the current landscape of T1D screening and prevention, as well as challenges and next steps moving into the future of these rapidly evolving areas of patient care.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/prevenção & controle , Qualidade de Vida , Medição de Risco
13.
medRxiv ; 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37131690

RESUMO

Background: Type 1 diabetes (T1D) results from immune-mediated destruction of insulin-producing beta cells. Efforts to prevent T1D have focused on modulating immune responses and supporting beta cell health; however, heterogeneity in disease progression and responses to therapies have made these efforts difficult to translate to clinical practice, highlighting the need for precision medicine approaches to T1D prevention. Methods: To understand the current state of knowledge regarding precision approaches to T1D prevention, we performed a systematic review of randomized-controlled trials from the past 25 years testing disease-modifying therapies in T1D and/or identifying features linked to treatment response, analyzing bias using a Cochrane-risk-of-bias instrument. Results: We identified 75 manuscripts, 15 describing 11 prevention trials for individuals with increased risk for T1D, and 60 describing treatments aimed at preventing beta cell loss in individuals at disease onset. Seventeen agents tested, mostly immunotherapies, showed benefit compared to placebo (only two prior to T1D onset). Fifty-seven studies employed precision analyses to assess features linked to treatment response. Age, measures of beta cell function and immune phenotypes were most frequently tested. However, analyses were typically not prespecified, with inconsistent methods reporting, and tended to report positive findings. Conclusions: While the quality of prevention and intervention trials was overall high, low quality of precision analyses made it difficult to draw meaningful conclusions that inform clinical practice. Thus, prespecified precision analyses should be incorporated into the design of future studies and reported in full to facilitate precision medicine approaches to T1D prevention. Plain Language Summary: Type 1 diabetes (T1D) results from the destruction of insulin-producing cells in the pancreas, necessitating lifelong insulin dependence. T1D prevention remains an elusive goal, largely due to immense variability in disease progression. Agents tested to date in clinical trials work in a subset of individuals, highlighting the need for precision medicine approaches to prevention. We systematically reviewed clinical trials of disease-modifying therapy in T1D. While age, measures of beta cell function, and immune phenotypes were most commonly identified as factors that influenced treatment response, the overall quality of these studies was low. This review reveals an important need to proactively design clinical trials with well-defined analyses to ensure that results can be interpreted and applied to clinical practice.

14.
Diabetes Care ; 46(5): 1098-1105, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37000695

RESUMO

OBJECTIVE: Metabolic zones were developed to characterize heterogeneity of individuals with islet autoantibodies. RESEARCH DESIGN AND METHODS: Baseline 2-h oral glucose tolerance test data from 6,620 TrialNet Pathway to Prevention Study (TNPTP) autoantibody-positive participants (relatives of individuals with type 1 diabetes) were used to form 25 zones from five area under the curve glucose (AUCGLU) rows and five area under the curve C-peptide (AUCPEP) columns. Zone phenotypes were developed from demographic, metabolic, autoantibody, HLA, and risk data. RESULTS: As AUCGLU increased, changes of glucose and C-peptide response curves (from mean glucose and mean C-peptide values at 30, 60, 90, and 120 min) were similar within the five AUCPEP columns. Among the zones, 5-year risk for type 1 diabetes was highly correlated with islet antigen 2 antibody prevalence (r = 0.96, P < 0.001). Disease risk decreased markedly in the highest AUCGLU row as AUCPEP increased (0.88-0.41; P < 0.001 from lowest AUCPEP column to highest AUCPEP column). AUCGLU correlated appreciably less with Index60 (an indicator of insulin secretion) in the highest AUCPEP column (r = 0.33) than in other columns (r ≥ 0.78). AUCGLU was positively related to "fasting glucose × fasting insulin" and to "fasting glucose × fasting C-peptide" (indicators of insulin resistance) before and after adjustments for Index60 (P < 0.001). CONCLUSIONS: Phenotypes of 25 zones formed from AUCGLU and AUCPEP were used to gain insights into type 1 diabetes heterogeneity. Zones were used to examine GCRC changes with increasing AUCGLU, associations between risk and autoantibody prevalence, the dependence of glucose as a predictor of risk according to C-peptide, and glucose heterogeneity from contributions of insulin secretion and insulin resistance.


Assuntos
Diabetes Mellitus Tipo 1 , Resistência à Insulina , Humanos , Glucose , Glicemia/metabolismo , Peptídeo C/metabolismo , Autoanticorpos , Insulina/metabolismo , Fenótipo
15.
Diabetes ; 72(6): 746-757, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36913741

RESUMO

The transcriptional activity of Pdx1 is modulated by a diverse array of coregulatory factors that govern chromatin accessibility, histone modifications, and nucleosome distribution. We previously identified the Chd4 subunit of the nucleosome remodeling and deacetylase complex as a Pdx1-interacting factor. To identify how loss of Chd4 impacts glucose homeostasis and gene expression programs in ß-cells in vivo, we generated an inducible ß-cell-specific Chd4 knockout mouse model. Removal of Chd4 from mature islet ß-cells rendered mutant animals glucose intolerant, in part due to defects in insulin secretion. We observed an increased ratio of immature-to-mature insulin granules in Chd4-deficient ß-cells that correlated with elevated levels of proinsulin both within isolated islets and from plasma following glucose stimulation in vivo. RNA sequencing and assay for transposase-accessible chromatin with sequencing showed that lineage-labeled Chd4-deficient ß-cells have alterations in chromatin accessibility and altered expression of genes critical for ß-cell function, including MafA, Slc2a2, Chga, and Chgb. Knockdown of CHD4 from a human ß-cell line revealed similar defects in insulin secretion and alterations in several ß-cell-enriched gene targets. These results illustrate how critical Chd4 activities are in controlling genes essential for maintaining ß-cell function. ARTICLE HIGHLIGHTS: Pdx1-Chd4 interactions were previously shown to be compromised in ß-cells from human donors with type 2 diabetes. ß-Cell-specific removal of Chd4 impairs insulin secretion and leads to glucose intolerance in mice. Expression of key ß-cell functional genes and chromatin accessibility are compromised in Chd4-deficient ß-cells. Chromatin remodeling activities enacted by Chd4 are essential for ß-cell function under normal physiological conditions.


Assuntos
Cromatina , Diabetes Mellitus Tipo 2 , Camundongos , Animais , Humanos , Cromatina/genética , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Diabetes Mellitus Tipo 2/genética , DNA Helicases/genética , Camundongos Knockout , Expressão Gênica , Glucose
16.
J Endocr Soc ; 7(3): bvad003, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36741943

RESUMO

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.

17.
JAMA ; 329(12): 980-989, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36826834

RESUMO

Importance: Near normalization of glucose levels instituted immediately after diagnosis of type 1 diabetes has been postulated to preserve pancreatic beta cell function by reducing glucotoxicity. Previous studies have been hampered by an inability to achieve tight glycemic goals. Objective: To determine the effectiveness of intensive diabetes management to achieve near normalization of glucose levels on preservation of pancreatic beta cell function in youth with newly diagnosed type 1 diabetes. Design, Setting, and Participants: This randomized, double-blind, clinical trial was conducted at 6 centers in the US (randomizations from July 20, 2020, to October 13, 2021; follow-up completed September 15, 2022) and included youths with newly diagnosed type 1 diabetes aged 7 to 17 years. Interventions: Random assignment to intensive diabetes management, which included use of an automated insulin delivery system (n = 61), or standard care, which included use of a continuous glucose monitor (n = 52), as part of a factorial design in which participants weighing 30 kg or more also were assigned to receive either oral verapamil or placebo. Main Outcomes and Measures: The primary outcome was mixed-meal tolerance test-stimulated C-peptide area under the curve (a measure of pancreatic beta cell function) 52 weeks from diagnosis. Results: Among 113 participants (mean [SD] age, 11.8 [2.8] years; 49 females [43%]; mean [SD] time from diagnosis to randomization, 24 [5] days), 108 (96%) completed the trial. The mean C-peptide area under the curve decreased from 0.57 pmol/mL at baseline to 0.45 pmol/mL at 52 weeks in the intensive management group, and from 0.60 to 0.50 pmol/mL in the standard care group (treatment group difference, -0.01 [95% CI, -0.11 to 0.10]; P = .89). The mean time in the target range of 70 to 180 mg/dL, measured with continuous glucose monitoring, at 52 weeks was 78% in the intensive management group vs 64% in the standard care group (adjusted difference, 16% [95% CI, 10% to 22%]). One severe hypoglycemia event and 1 diabetic ketoacidosis event occurred in each group. Conclusions and Relevance: In youths with newly diagnosed type 1 diabetes, intensive diabetes management, which included automated insulin delivery, achieved excellent glucose control but did not affect the decline in pancreatic C-peptide secretion at 52 weeks. Trial Registration: ClinicalTrials.gov Identifier: NCT04233034.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Feminino , Adolescente , Humanos , Criança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/administração & dosagem , Glicemia/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Peptídeo C/farmacologia , Peptídeo C/uso terapêutico , Método Duplo-Cego , Controle Glicêmico , Automonitorização da Glicemia , Hemoglobinas Glicadas , Insulina/efeitos adversos , Insulina/administração & dosagem
18.
JAMA ; 329(12): 990-999, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36826844

RESUMO

Importance: In preclinical studies, thioredoxin-interacting protein overexpression induces pancreatic beta cell apoptosis and is involved in glucotoxicity-induced beta cell death. Calcium channel blockers reduce these effects and may be beneficial to beta cell preservation in type 1 diabetes. Objective: To determine the effect of verapamil on pancreatic beta cell function in children and adolescents with newly diagnosed type 1 diabetes. Design, Setting, and Participants: This double-blind, randomized clinical trial including children and adolescents aged 7 to 17 years with newly diagnosed type 1 diabetes who weighed 30 kg or greater was conducted at 6 centers in the US (randomized participants between July 20, 2020, and October 13, 2021) and follow-up was completed on September 15, 2022. Interventions: Participants were randomly assigned 1:1 to once-daily oral verapamil (n = 47) or placebo (n = 41) as part of a factorial design in which participants also were assigned to receive either intensive diabetes management or standard diabetes care. Main Outcomes and Measures: The primary outcome was area under the curve values for C-peptide level (a measure of pancreatic beta cell function) stimulated by a mixed-meal tolerance test at 52 weeks from diagnosis of type 1 diabetes. Results: Among 88 participants (mean age, 12.7 [SD, 2.4] years; 36 were female [41%]; and the mean time from diagnosis to randomization was 24 [SD, 4] days), 83 (94%) completed the trial. In the verapamil group, the mean C-peptide area under the curve was 0.66 pmol/mL at baseline and 0.65 pmol/mL at 52 weeks compared with 0.60 pmol/mL at baseline and 0.44 pmol/mL at 52 weeks in the placebo group (adjusted between-group difference, 0.14 pmol/mL [95% CI, 0.01 to 0.27 pmol/mL]; P = .04). This equates to a 30% higher C-peptide level at 52 weeks with verapamil. The percentage of participants with a 52-week peak C-peptide level of 0.2 pmol/mL or greater was 95% (41 of 43 participants) in the verapamil group vs 71% (27 of 38 participants) in the placebo group. At 52 weeks, hemoglobin A1c was 6.6% in the verapamil group vs 6.9% in the placebo group (adjusted between-group difference, -0.3% [95% CI, -1.0% to 0.4%]). Eight participants (17%) in the verapamil group and 8 participants (20%) in the placebo group had a nonserious adverse event considered to be related to treatment. Conclusions and Relevance: In children and adolescents with newly diagnosed type 1 diabetes, verapamil partially preserved stimulated C-peptide secretion at 52 weeks from diagnosis compared with placebo. Further studies are needed to determine the longitudinal durability of C-peptide improvement and the optimal length of therapy. Trial Registration: ClinicalTrials.gov Identifier: NCT04233034.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Adolescente , Humanos , Criança , Feminino , Masculino , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Peptídeo C/metabolismo , Peptídeo C/farmacologia , Peptídeo C/uso terapêutico , Método Duplo-Cego , Verapamil/efeitos adversos , Células Secretoras de Insulina/efeitos dos fármacos
20.
Diabetes Care ; 45(12): 2982-2990, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36326757

RESUMO

OBJECTIVE: We studied longitudinal differences between progressors and nonprogressors to type 1 diabetes with similar and substantial baseline risk. RESEARCH DESIGN AND METHODS: Changes in 2-h oral glucose tolerance test indices were used to examine variability in diabetes progression in the Diabetes Prevention Trial-Type 1 (DPT-1) study (n = 246) and Type 1 Diabetes TrialNet Pathway to Prevention study (TNPTP) (n = 503) among autoantibody (Ab)+ children (aged <18.0 years) with similar baseline metabolic impairment (DPT-1 Risk Score [DPTRS] of 6.5-7.5), as well as in TNPTP Ab- children (n = 94). RESULTS: Longitudinal analyses revealed annualized area under the curve (AUC) of C-peptide increases in nonprogressors versus decreases in progressors (P ≤ 0.026 for DPT-1 and TNPTP). Vector indices for AUC glucose and AUC C-peptide changes (on a two-dimensional grid) also differed significantly (P < 0.001). Despite marked baseline metabolic impairment of nonprogressors, changes in AUC C-peptide, AUC glucose, AUC C-peptide-to-AUC glucose ratio (AUC ratio), and Index60 did not differ from Ab- relatives during follow-up. Divergence between nonprogressors and progressors occurred by 6 months from baseline in both cohorts (AUC glucose, P ≤ 0.007; AUC ratio, P ≤ 0.034; Index60, P < 0.001; vector indices of change, P < 0.001). Differences in 6-month change were positively associated with greater diabetes risk (respectively, P < 0.001, P ≤ 0.019, P < 0.001, and P < 0.001) in DPT-1 and TNPTP, except AUC ratio, which was inversely associated with risk (P < 0.001). CONCLUSIONS: Novel findings show that even with similarly abnormal baseline risk, progressors had appreciably more metabolic impairment than nonprogressors within 6 months and that the measures showing impairment were predictive of type 1 diabetes. Longitudinal metabolic patterns did not differ between nonprogressors and Ab- relatives, suggesting persistent ß-cell responsiveness in nonprogressors.


Assuntos
Diabetes Mellitus Tipo 1 , Criança , Humanos , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/diagnóstico , Glicemia/metabolismo , Teste de Tolerância a Glucose , Autoanticorpos , Glucose , Progressão da Doença
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