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1.
Diabet Med ; : e15340, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741266

RESUMO

AIMS: Impaired awareness of hypoglycaemia (IAH) increases the risk of severe hypoglycaemia in people with type 1 diabetes mellitus (T1DM). IAH can be reversed through meticulous avoidance of hypoglycaemia. Diabetic autonomic neuropathy (DAN) has been proposed as an underlying mechanism contributing to IAH; however, data are inconsistent. The aim of this study was to examine the effects of cardiac autonomic neuropathy (CAN) on IAH reversibility inT1DM. METHODS: Participants with T1DM and IAH (Gold score ≥4) recruited to the HypoCOMPaSS (24-week 2 × 2 factorial randomised controlled) trial were included. All underwent screening for cardiac autonomic function testing at baseline and received comparable education and support aimed at avoiding hypoglycaemia and improving hypoglycaemia awareness. Definite CAN was defined as the presence of ≥2 abnormal cardiac reflex tests. Participants were grouped according to their CAN status, and changes in Gold score were compared. RESULTS: Eighty-three participants (52 women [62.7%]) were included with mean age (SD) of 48 (12) years and mean HbA1c of 66 (13) mmol/mol (8.2 [3.3] %). The mean duration of T1DM was 29 (13) years. The prevalence of CAN was low with 5/83 (6%) participants having definite autonomic neuropathy with 11 (13%) classified with possible/early neuropathy. All participants, regardless of the autonomic function status, showed a mean improvement in Gold score of ≥1 (mean improvement -1.2 [95% CI -0.8, -1.6]; p < 0.001). CONCLUSIONS: IAH can be improved in people with T1DM, and a long duration of disease, with and without cardiac autonomic dysfunction. These data suggest that CAN is not a prime driver for modulating IAH reversibility.

2.
Contemp Clin Trials ; 139: 107456, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38253252

RESUMO

BACKGROUND: Severe hypoglycemia is a common and feared complication of medications used to lower blood glucose levels in individuals with diabetes. Psychoeducational interventions can prevent severe hypoglycemia in individuals with type 1 diabetes (T1D). We aim to determine the effectiveness of this approach among adults with type 2 diabetes (T2D) at elevated risk for severe hypoglycemia. METHODS: Preventing Hypoglycemia in Type 2 diabetes (PHT2) is a two-arm, parallel, randomized controlled trial. Participants are eligible if they are adults with T2D receiving care at an integrated group practice in Washington state and have experienced one or more episodes of severe hypoglycemia in the prior 12 months or have impaired awareness of hypoglycemia (Gold score ≥ 4). Participants are randomized to proactive nurse care management with or without my hypo compass, an evidence-based, psychoeducational intervention combining group and individual self-management training. For this study, my hypo compass was adapted to be suitable for adults with T2D and from an in-person to a virtual intervention over videoconference and telephone. The primary outcome is any self-reported severe hypoglycemia in the 12 months following the start of the intervention. Secondary outcomes include biochemical measures of hypoglycemia, self-reported hypoglycemia awareness, fear of hypoglycemia, and emergency department visits and hospitalizations for severe hypoglycemia. The study includes a process evaluation to assess implementation fidelity and clarify the causal pathway. CONCLUSION: The PHT2 trial will compare the effectiveness of two approaches for reducing severe hypoglycemia in adults with T2D. TRIAL REGISTRATION: clinicaltrials.gov, # NCT04863872.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemia , Adulto , Humanos , Glicemia/metabolismo , Automonitorização da Glicemia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemia/induzido quimicamente , Hipoglicemia/prevenção & controle , Hipoglicemiantes/efeitos adversos , Insulina/efeitos adversos
3.
Diabet Med ; 41(1): e15231, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37746767

RESUMO

AIMS: To determine the frequency, severity, burden, and utility of hypoglycaemia symptoms among adults with type 1 diabetes (T1D) and impaired awareness of hypoglycaemia (IAH) at baseline and week 24 following the HypoCOMPaSS awareness restoration intervention. METHODS: Adults (N = 96) with T1D (duration: 29 ± 12 years; 64% women) and IAH completed the Hypoglycaemia Burden Questionnaire (HypoB-Q), assessing experience of 20 pre-specified hypoglycaemia symptoms, at baseline and week 24. RESULTS: At baseline, 93 (97%) participants experienced at least one symptom (mean ± SD 10.6 ± 4.6 symptoms). The proportion recognising each specific symptom ranged from 15% to 83%. At 24 weeks, symptom severity and burden appear reduced, and utility increased. CONCLUSIONS: Adults with T1D and IAH experience a range of hypoglycaemia symptoms. Perceptions of symptom burden or utility are malleable. Although larger scale studies are needed to confirm, these findings suggest that changing the salience of the symptomatic response may be more important in recovering protection from hypoglycaemia through regained awareness than intensifying symptom frequency or severity.


Assuntos
Diabetes Mellitus Tipo 1 , Hipoglicemia , Adulto , Humanos , Feminino , Masculino , Diabetes Mellitus Tipo 1/complicações , Conscientização , Hipoglicemia/epidemiologia , Hipoglicemia/prevenção & controle , Hipoglicemia/diagnóstico , Inquéritos e Questionários
4.
Transpl Int ; 36: 11633, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822447

RESUMO

The field of transplantation has witnessed the emergence of Advanced Therapy Medicinal Products (ATMPs) as highly promising solutions to address the challenges associated with organ and tissue transplantation. ATMPs encompass gene therapy, cell therapy, and tissue-engineered products, hold immense potential for breakthroughs in overcoming the obstacles of rejection and the limited availability of donor organs. However, the development and academic research access to ATMPs face significant bottlenecks that hinder progress. This opinion paper emphasizes the importance of addressing bottlenecks in the development and academic research access to ATMPs by implementing several key strategies. These include the establishment of streamlined regulatory processes, securing increased funding for ATMP research, fostering collaborations and partnerships, setting up centralized ATMP facilities, and actively engaging with patient groups. Advocacy at the policy level is essential to provide support for the development and accessibility of ATMPs, thereby driving advancements in transplantation and enhancing patient outcomes. By adopting these strategies, the field of transplantation can pave the way for the introduction of innovative and efficacious ATMP therapies, while simultaneously fostering a nurturing environment for academic research.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Engenharia Tecidual , Humanos , Terapia Genética
5.
Transpl Int ; 36: 11659, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822448

RESUMO

Associations between islet graft function and well-being in islet transplant recipients requiring exogenous insulin remain unclear. This cross-sectional analysis compared person-reported outcome measures in 15 adults with type 1 diabetes whose islet transplants were classified according to Igls criteria as "Good" (n = 5), "Marginal" (n = 4) and "Failed" (n = 6) graft function. At a mean of 6.2 years post-first islet transplant, 90% reduction in severe hypoglycaemia was maintained in all groups, with HbA1c (mean ± SD mmol/mol) 49 ± 4 in recipients with "Good" function; 56 ± 5 ("Marginal"); and 69 ± 25 ("Failed"). Self-reported impaired awareness of hypoglycaemia persisted in all groups but those with "Good" function were more likely to experience symptoms during hypoglycaemia. "Marginal" function was associated with greater fear of hypoglycaemia (HFS-II score: "Marginal": 113 [95, 119]; "Failed": 63 [42, 93] (p = 0.082); "Good": 33 [29, 61]) and severe anxiety (GAD7: "Marginal"): 21 [17, 21]; "Failed": 6 [6, 6] "Good": 6 [3, 11]; (p = 0.079)), diabetes distress and low mood. Despite clear evidence of ongoing clinical benefit, Igls criteria 'Marginal' function is associated with sub-optimal well-being, including greater fear of hypoglycaemia and severe anxiety. This study provides person-reported validation that "Good" and "Marginal" graft function are differentiated by general and diabetes-specific subjective well-being, suggesting those with "Marginal" function may benefit from further intervention, including re-transplantation.


Assuntos
Diabetes Mellitus Tipo 1 , Hipoglicemia , Transplante das Ilhotas Pancreáticas , Adulto , Humanos , Estudos Transversais , Estado Funcional , Diabetes Mellitus Tipo 1/cirurgia , Diabetes Mellitus Tipo 1/complicações , Hipoglicemia/complicações , Medidas de Resultados Relatados pelo Paciente
6.
Front Endocrinol (Lausanne) ; 14: 1249876, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37720541

RESUMO

Aims: The purpose of the study was to further elucidate the pathophysiology of cystic fibrosis (CF)-related diabetes (CFRD) and potential drivers of hypoglycaemia. Hence, we aimed to describe and compare beta cell function (insulin and proinsulin) and alpha cell function (glucagon) in relation to glucose tolerance in adults with CF and to study whether hypoglycaemia following oral glucose challenge may represent an early sign of islet cell impairment. Methods: Adults with CF (≥18 years) were included in a cross-sectional study using an extended (-10, -1, 10, 20, 30, 45, 60, 90, 120, 150, and 180 min) or a standard (-1, 30, 60, and 120 min) oral glucose tolerance test (OGTT). Participants were classified according to glucose tolerance status and hypoglycaemia was defined as 3-hour glucose <3.9 mmol/L in those with normal glucose tolerance (NGT) and early glucose intolerance (EGI). Results: Among 93 participants, 67 underwent an extended OGTT. In addition to worsening in insulin secretion, the progression to CFRD was associated with signs of beta cell stress, as the fasting proinsulin-to-insulin ratio incrementally increased (p-value for trend=0.013). The maximum proinsulin level (pmol/L) was positively associated with the nadir glucagon, as nadir glucagon increased 6.2% (95% confidence interval: 1.4-11.3%) for each unit increase in proinsulin. Those with hypoglycaemia had higher 60-min glucose, 120-min C-peptide, and 180-min glucagon levels (27.8% [11.3-46.7%], 42.9% [5.9-92.85%], and 80.3% [14.9-182.9%], respectively) and unaltered proinsulin-to-insulin ratio compared to those without hypoglycaemia. Conclusions: The maximum proinsulin concentration was positively associated with nadir glucagon during the OGTT, suggesting that beta cell stress is associated with abnormal alpha cell function in adults with CF. In addition, hypoglycaemia seemed to be explained by a temporal mismatch between glucose and insulin levels rather than by an impaired glucagon response.


Assuntos
Fibrose Cística , Hipoglicemia , Adulto , Humanos , Glucagon , Estudos Transversais , Proinsulina , Fibrose Cística/complicações , Glucose
7.
Diabetes Obes Metab ; 25(12): 3529-3537, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37646197

RESUMO

BACKGROUND: Donor hyperglycaemia following brain death has been attributed to reversible insulin resistance. However, our islet and pancreas transplant data suggest that other mechanisms may be predominant. We aimed to determine the relationships between donor insulin use and markers of beta-cell death and beta-cell function in pancreas donors after brain death. METHODS: In pancreas donors after brain death, we compared clinical and biochemical data in 'insulin-treated' and 'not insulin-treated donors' (IT vs. not-IT). We measured plasma glucose, C-peptide and levels of circulating unmethylated insulin gene promoter cell-free DNA (INS-cfDNA) and microRNA-375 (miR-375), as measures of beta-cell death. Relationships between markers of beta-cell death and islet isolation outcomes and post-transplant function were also evaluated. RESULTS: Of 92 pancreas donors, 40 (43%) required insulin. Glycaemic control and beta-cell function were significantly poorer in IT donors versus not-IT donors [median (IQR) peak glucose: 8 (7-11) vs. 6 (6-8) mmol/L, p = .016; C-peptide: 3280 (3159-3386) vs. 3195 (2868-3386) pmol/L, p = .046]. IT donors had significantly higher levels of INS-cfDNA [35 (18-52) vs. 30 (8-51) copies/ml, p = .035] and miR-375 [1.050 (0.19-1.95) vs. 0.73 (0.32-1.10) copies/nl, p = .05]. Circulating donor miR-375 was highly predictive of recipient islet graft failure at 3 months [adjusted receiver operator curve (SE) = 0.813 (0.149)]. CONCLUSIONS: In pancreas donors, hyperglycaemia requiring IT is strongly associated with beta-cell death. This provides an explanation for the relationship of donor IT with post-transplant beta-cell dysfunction in transplant recipients.


Assuntos
Ácidos Nucleicos Livres , Hiperglicemia , Transplante das Ilhotas Pancreáticas , MicroRNAs , Humanos , Peptídeo C , Morte Encefálica , Insulina/genética , Doadores de Tecidos , Morte Celular
8.
Diabetologia ; 66(4): 631-641, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36538062

RESUMO

AIMS/HYPOTHESIS: The aims of this study were to assess cognitions relating to hypoglycaemia in adults with type 1 diabetes and impaired awareness of hypoglycaemia before and after the multimodal HypoCOMPaSS intervention, and to determine cognitive predictors of incomplete response (one or more severe hypoglycaemic episodes over 24 months). METHODS: This analysis included 91 adults with type 1 diabetes and impaired awareness of hypoglycaemia who completed the Attitudes to Awareness of Hypoglycaemia (A2A) questionnaire before, 24 weeks and 24 months after the intervention, which comprised a short psycho-educational programme with optimisation of insulin therapy and glucose monitoring. RESULTS: The age and diabetes duration of the participants were 48±12 and 29±12 years, respectively (mean±SD). At baseline, 91% reported one or more severe hypoglycaemic episodes over the preceding 12 months; this decreased to <20% at 24 weeks and after 24 months (p=0.001). The attitudinal barrier 'hyperglycaemia avoidance prioritised' (η2p=0.250, p=0.001) decreased from baseline to 24 weeks, and this decrease was maintained at 24 months (mean±SD=5.3±0.3 vs 4.3±0.3 vs 4.0±0.3). The decrease in 'asymptomatic hypoglycaemia normalised' from baseline (η2p=0.113, p=0.045) was significant at 24 weeks (1.5±0.3 vs 0.8±0.2). Predictors of incomplete hypoglycaemia response (one or more further episodes of severe hypoglycaemia) were higher baseline rates of severe hypoglycaemia, higher baseline scores for 'asymptomatic hypoglycaemia normalised', reduced change in 'asymptomatic hypoglycaemia normalised' scores at 24 weeks, and lower baseline 'hypoglycaemia concern minimised' scores (all p<0.05). CONCLUSIONS/INTERPRETATION: Participation in the HypoCOMPaSS RCT was associated with improvements in hypoglycaemia-associated cognitions, with 'hyperglycaemia avoidance prioritised' most prevalent. Incomplete prevention of subsequent severe hypoglycaemia episodes was associated with persistence of the cognition 'asymptomatic hypoglycaemia normalised'. Understanding and addressing cognitive barriers to hypoglycaemia avoidance is important in individuals prone to severe hypoglycaemia episodes. CLINICAL TRIALS REGISTRATION: www.isrctn.org : ISRCTN52164803 and https://eudract.ema.europa.eu : EudraCT2009-015396-27.


Assuntos
Diabetes Mellitus Tipo 1 , Hiperglicemia , Hipoglicemia , Adulto , Humanos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Glicemia , Automonitorização da Glicemia , Hipoglicemia/tratamento farmacológico , Insulina/uso terapêutico , Conscientização , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Atitude
9.
Cells ; 11(15)2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35954174

RESUMO

Appropriate glucose-stimulated insulin secretion (GSIS) by pancreatic ß-cells is an essential component of blood glucose homeostasis. Configuration of ß-cells as 3D pseudoislets (PI) improves the GSIS response compared to 2D monolayer (ML) culture. The aim of this study was to determine the underlying mechanisms. MIN6 ß-cells were grown as ML or PI for 5 days. Human islets were isolated from patients without diabetes. Function was assessed by GSIS and metabolic capacity using the Seahorse bioanalyser. Connexin 36 was downregulated using inducible shRNA. Culturing MIN6 as PI improved GSIS. MIN6 PI showed higher glucose-stimulated oxygen consumption (OCR) and extracellular acidification (ECAR) rates. Further analysis showed the higher ECAR was, at least in part, a consequence of increased glycolysis. Intact human islets also showed glucose-stimulated increases in both OCR and ECAR rates, although the latter was smaller in magnitude compared to MIN6 PI. The higher rates of glucose-stimulated ATP production in MIN6 PI were consistent with increased enzyme activity of key glycolytic and TCA cycle enzymes. There was no impact of connexin 36 knockdown on GSIS or ATP production. Configuration of ß-cells as PI improves GSIS by increasing the metabolic capacity of the cells, allowing higher ATP production in response to glucose.


Assuntos
Glucose , Células Secretoras de Insulina , Trifosfato de Adenosina/metabolismo , Glucose/metabolismo , Glucose/farmacologia , Humanos , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo
10.
Diabet Med ; 39(5): e14814, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35181926

RESUMO

AIMS: Many individuals with type 1 diabetes retain residual ß-cell function, with increased endogenous insulin secretion associated with reduced hyperglycaemia, hypoglycaemia and glycaemic variability. However, it is unknown when these improvements occur during the day. Dysglycaemia is common in overnight and postprandial periods and associated with diabetes complications. Therefore, this study aimed to determine the influence of residual ß-cell function upon nocturnal and postprandial glycaemic control in established type 1 diabetes. METHODS: Under free-living conditions, 66 participants wore a blinded continuous glucose monitor (CGM), kept a food diary, and completed a stimulated urine C-peptide creatinine (UCPCR) test. Nocturnal, and postprandial CGM outcomes (participant means and discrete event analysis) were compared between UCPCR groups: undetectable (Cpepund ), low (Cpeplow : 0.001-0.19 nmol/mmol) and high (Cpephigh : ≥0.2 nmol/mmol). RESULTS: Greater ß-cell function was associated with incremental improvements in glycaemia. Cpephigh spent significantly greater time in normoglycaemia than Cpepund overnight (76 ± 20% vs. 58 ± 20%, p = 0.005) and 0-300 mins postprandially (68 ± 22% vs. 51 ± 22%, p = 0.045), while also having reducing nocturnal variability (SD 1.12 ± 0.41 vs. 1.52 ± 0.43 mmol/L, p = 0.010). Analysis of individual events, controlling for diabetes duration, BMI, basal insulin, use of a continuous or flash glucose monitor and (for postprandial) meal type, carbohydrate and bolus insulin intake, replicated the group findings, additionally demonstrating Cpepund had increased hyperglycaemia versus Cpeplow overnight and increased postprandial hypoglycaemic events compared with Cpephigh . For all participants, breakfast had a significantly higher incremental area under the curve than lunch and dinner. CONCLUSIONS: Residual ß-cell function is associated with improved nocturnal and postprandial glycaemic control. These data may be of clinical importance for identifying specific periods and individuals where further glycaemic management strategies would be beneficial.


Assuntos
Diabetes Mellitus Tipo 1 , Hiperglicemia , Hipoglicemia , Glicemia/análise , Estudos Cross-Over , Diabetes Mellitus Tipo 1/tratamento farmacológico , Progressão da Doença , Humanos , Hiperglicemia/prevenção & controle , Insulina , Período Pós-Prandial
11.
Am J Transplant ; 22(1): 154-164, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34355503

RESUMO

The UK islet allotransplant program is nationally funded to deliver one or two transplants over 12 months to individuals with type 1 diabetes and recurrent severe hypoglycemia. Analyses were undertaken 10 years after program inception to evaluate associations between transplanted mass; single versus two transplants; time between two transplants and graft survival (stimulated C-peptide >50 pmol/L) and function. In total, 84 islet transplant recipients were studied. Uninterrupted graft survival over 12 months was attained in 23 (68%) single and 47 (94%) (p = .002) two transplant recipients (separated by [median (IQR)] 6 (3-8) months). 64% recipients of one or two transplants with uninterrupted function at 12 months sustained graft function at 6 years. Total transplanted mass was associated with Mixed Meal Tolerance Test stimulated C-peptide at 12 months (p < .01). Despite 1.9-fold greater transplanted mass in recipients of two versus one islet infusion (12 218 [9291-15 417] vs. 6442 [5156-7639] IEQ/kg; p < .0001), stimulated C-peptide was not significantly higher. Shorter time between transplants was associated with greater insulin dose reduction at 12 months (beta -0.35; p = .02). Graft survival over the first 12 months was greater in recipients of two versus one islet transplant in the UK program, although function at 1 and 6 years was comparable. Minimizing the interval between 2 islet infusions may maximize cumulative impact on graft function.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Peptídeo C , Diabetes Mellitus Tipo 1/cirurgia , Sobrevivência de Enxerto , Humanos , Insulina
12.
Transplant Direct ; 8(1): e1271, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34934809

RESUMO

BACKGROUND: Pancreas and islet transplantation outcomes are negatively impacted by injury to the endocrine cells from acute stress during donor death, organ procurement, processing, and transplant procedures. Here, we report a novel electron microscopy scoring system, the Newcastle Pancreas Endocrine Stress Score (NPESS). METHODS: NPESS was adapted and expanded from our previously validated method for scoring pancreatic exocrine acinar cells, yielding a 4-point scale (0-3) classifying ultrastructural pathology in endocrine cell nuclei, mitochondria, endoplasmic reticulum, cytoplasmic vacuolization, and secretory granule depletion, with a maximum additive score of 15. We applied NPESS in a cohort of deceased organ donors after brainstem (DBD) and circulatory (DCD) death with a wide range of cold ischemic times (3.6-35.9 h) including 3 donors with type 1 and 3 with type 2 diabetes to assess islets in situ (n = 30) in addition to pancreata (n = 3) pre- and postislet isolation. RESULTS: In DBD pancreata, NPESS correlated with cold ischemic time (head: r = 0.55; P = 0.02) and mirrored exocrine score (r = 0.48; P = 0.01). When stratified by endocrine phenotype, cells with granules of heterogeneous morphology had higher scores than α, ß, and δ cells (P < 0.0001). Cells of mixed endocrine-exocrine morphology were observed in association with increased NPESS (P = 0.02). Islet isolation was associated with improved NPESS (in situ: 8.39 ± 0.77 [Mean ± SD]; postisolation: 5.44 ± 0.31; P = 0.04). CONCLUSIONS: NPESS provides a robust method for semiquantitative scoring of subcellular ultrastructural changes in human pancreatic endocrine cells in situ and following islet isolation with utility for unbiased evaluation of acute stress in organ transplantation research.

13.
Lancet Diabetes Endocrinol ; 9(10): 708-724, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34480875

RESUMO

Type 1 diabetes is characterised by autoimmune-mediated destruction of pancreatic ß-cell mass. With the advent of insulin therapy a century ago, type 1 diabetes changed from a progressive, fatal disease to one that requires lifelong complex self-management. Replacing the lost ß-cell mass through transplantation has proven successful, but limited donor supply and need for lifelong immunosuppression restricts widespread use. In this Review, we highlight incremental advances over the past 20 years and remaining challenges in regenerative medicine approaches to restoring ß-cell mass and function in type 1 diabetes. We begin by summarising the role of endocrine islets in glucose homoeostasis and how this is altered in disease. We then discuss the potential regenerative capacity of the remaining islet cells and the utility of stem cell-derived ß-like cells to restore ß-cell function. We conclude with tissue engineering approaches that might improve the engraftment, function, and survival of ß-cell replacement therapies.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Ilhotas Pancreáticas/fisiologia , Medicina Regenerativa , Animais , Contagem de Células , Proliferação de Células/fisiologia , Diabetes Mellitus Tipo 1/fisiopatologia , História do Século XXI , Humanos , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/fisiologia , Células Secretoras de Insulina/transplante , Ilhotas Pancreáticas/citologia , Transplante das Ilhotas Pancreáticas/história , Transplante das Ilhotas Pancreáticas/métodos , Transplante das Ilhotas Pancreáticas/tendências , Regeneração/fisiologia , Medicina Regenerativa/história , Medicina Regenerativa/métodos , Medicina Regenerativa/tendências , Engenharia Tecidual/história , Engenharia Tecidual/métodos , Engenharia Tecidual/tendências
14.
Ann N Y Acad Sci ; 1495(1): 40-54, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33550589

RESUMO

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by pancreatic islet ß cell loss and dysfunction resulting in insulin deficiency and hyperglycemia. During a presymptomatic phase of established ß cell autoimmunity, ß cell loss may first be evident through assessment of ß cell secretory capacity, a measure of functional ß cell mass. Reduction in pancreatic islet ß cell reserve eventually manifests as impaired first-phase insulin response to glucose and abnormal glucose tolerance, which progresses until the functional capacity for ß cell secretion can no longer meet the demand for insulin to control glycemia. A functional ß cell mass of ∼25% of normal may be required to avoid symptomatic T1D but is already associated with dysregulated glucagon secretion. With symptomatic T1D, stimulated C-peptide levels >0.60 ng/mL (0.200 pmol/mL) indicate the presence of clinically meaningful residual ß cell function for contributing to glycemic control, although even higher residual C-peptide appears necessary for evidencing glucose-dependent islet ß and α cell function that may contribute to maintaining (near)normal glycemia. ß cell replacement by islet transplantation can restore a physiologic reserve capacity for insulin secretion, confirming thresholds for functional ß cell mass required for independence from insulin therapy.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Secreção de Insulina/fisiologia , Células Secretoras de Insulina/patologia , Insulina/biossíntese , Glucagon/metabolismo , Glucose/metabolismo , Humanos , Hiperglicemia/patologia , Insulina/metabolismo , Células Secretoras de Insulina/imunologia
15.
Lancet Diabetes Endocrinol ; 8(12): 939-948, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33031736

RESUMO

BACKGROUND: The pancreas is small and irregular in shape in people with type 2 diabetes. If these abnormalities are caused by the disease state itself rather than being a predisposing factor, remission of type 2 diabetes should restore normal pancreas morphology. The objective of this study was to determine whether changes in pancreas volume and shape occurred during 2 years of remission. METHODS: For this post-hoc analysis, we included a subset of adult participants of the Diabetes Remission Clinical Trial (DiRECT), who had type 2 diabetes and were randomly assigned to a weight management intervention or routine diabetes management. Intervention group participants were categorised as responders (HbA1c <6·5% [48 mmol/mol] and fasting blood glucose <7·0 mmol/L, off all anti-diabetes medication) and non-responders, who were classified as remaining diabetic. Data on pancreas volume and irregularity of pancreas border at baseline, 5 months, 12 months, and 24 months after intervention were compared between responders and non-responders; additional comparisons were made between control group participants with type 2 diabetes and a non-diabetic comparator (NDC) group, who were matched to the intervention group by age, sex, and post-weight-loss weight, to determine the extent of any normalisation. We used a mixed-effects regression model based on repeated measures ANOVA with correction for potential confounding. Magnetic resonance techniques were employed to quantify pancreas volume, the irregularity of the pancreas borders, and intrapancreatic fat content. ß-cell function and biomarkers of tissue growth were also measured. FINDINGS: Between July 25, 2015, and Aug 5, 2016, 90 participants with type 2 diabetes in the DiRECT subset were randomly assigned to intervention (n=64) or control (n=26) and were assessed at baseline; a further 25 non-diabetic participants were enrolled into the NDC group. At baseline, mean pancreas volume was 61·7 cm3 (SD 16·0) in all participants with type 2 diabetes and 79·8 cm3 (14·3) in the NDC group (p<0·0001). At 24 months, pancreas volume had increased by 9·4 cm3 (95% CI 6·1 to 12·8) in responders compared with 6·4 cm3 (2·5 to 10·3) in non-responders (p=0·0008). Pancreas borders at baseline were more irregular in participants with type 2 diabetes than in the NDC group (fractal dimension 1·138 [SD 0·027] vs 1·097 [0·025]; p<0·0001) and had normalised by 24 months in responders only (1·099 [0·028]). Intrapancreatic fat declined by 1·02 percentage points (95% CI 0·53 to 1·51) in 32 responders and 0·51% (-0·17 to 1·19) in 13 non-responders (p=0·23). INTERPRETATION: These data show for the first time, to our knowledge, reversibility of the abnormal pancreas morphology of type 2 diabetes by weight loss-induced remission. FUNDING: Diabetes UK.


Assuntos
Biomarcadores/análise , Peso Corporal , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Pâncreas/efeitos dos fármacos , Redução de Peso , Adulto , Idoso , Glicemia/análise , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Feminino , Seguimentos , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/fisiopatologia , Prognóstico , Indução de Remissão , Adulto Jovem
16.
Diabetes Obes Metab ; 22(10): 1874-1879, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32452110

RESUMO

Insulin is routinely used to manage hyperglycaemia in organ donors and during the peri-transplant period in islet transplant recipients. However, it is unknown whether donor insulin use (DIU) predicts beta-cell dysfunction after islet transplantation. We reviewed data from the UK Transplant Registry and the UK Islet Transplant Consortium; all first-time transplants during 2008-2016 were included. Linear regression models determined associations between DIU, median and coefficient of variation (CV) peri-transplant glucose levels and 3-month islet graft function. In 91 islet cell transplant recipients, DIU was associated with lower islet function assessed by BETA-2 scores (ß [SE] -3.5 [1.5], P = .02), higher 3-month post-transplant HbA1c levels (5.4 [2.6] mmol/mol, P = .04) and lower fasting C-peptide levels (-107.9 [46.1] pmol/l, P = .02). Glucose at 10 512 time points was recorded during the first 5 days peri-transplant: the median (IQR) daily glucose level was 7.9 (7.0-8.9) mmol/L and glucose CV was 28% (21%-35%). Neither median glucose levels nor glucose CV predicted outcomes post-transplantation. Data on DIU predicts beta-cell dysfunction 3 months after islet transplantation and could help improve donor selection and transplant outcomes.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Transplante das Ilhotas Pancreáticas , Glicemia , Peptídeo C , Glucose , Humanos , Insulina , Doadores de Tecidos
17.
Endocrinology ; 161(4)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32065829

RESUMO

ß-Cell dysfunction in type 2 diabetes (T2D) is associated with loss of cellular identity and mis-expression of alternative islet hormones, including glucagon. The molecular basis for these cellular changes has been attributed to dysregulation of core ß-cell transcription factors, which regulate ß-cell identity through activating and repressive mechanisms. The TLE1 gene lies near a T2D susceptibility locus and, recently, the glucagon repressive actions of this transcriptional coregulator have been demonstrated in vitro. We investigated whether TLE1 expression is disrupted in human T2D, and whether this is associated with increased islet glucagon-expressing cells. Automated image analysis following immunofluorescence in donors with (n = 7) and without (n = 7) T2D revealed that T2D was associated with higher islet α/ß cell ratio (Control: 0.7 ± 0.1 vs T2D: 1.6 ± 0.4; P < .05) and an increased frequency of bihormonal (insulin+/glucagon+) cells (Control: 0.8 ± 0.2% vs T2D: 2.0 ± 0.4%, P < .05). In nondiabetic donors, the majority of TLE1-positive cells were mono-hormonal ß-cells (insulin+/glucagon-: 98.2 ± 0.5%; insulin+/glucagon+: 0.7 ± 0.2%; insulin-/glucagon+: 1.1 ± 0.4%; P < .001). TLE1 expression was reduced in T2D (Control: 36 ± 2.9% vs T2D: 24 ± 2.6%; P < .05). Reduced islet TLE1 expression was inversely correlated with α/ß cell ratio (r = -0.55; P < .05). TLE1 knockdown in EndoC-ßH1 cells was associated with a 2.5-fold increase in glucagon gene mRNA and mis-expression of glucagon in insulin-positive cells. These data support TLE1 as a putative regulator of human ß-cell identity, with dysregulated expression in T2D associated with increased glucagon expression potentially reflecting ß- to α-cell conversion.


Assuntos
Proteínas Correpressoras/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Glucagon/metabolismo , Glucagon/metabolismo , Adulto , Idoso , Diabetes Mellitus Tipo 2/patologia , Feminino , Células Secretoras de Glucagon/patologia , Humanos , Secreção de Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Pessoa de Meia-Idade
18.
Diabetes Care ; 43(4): 710-718, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019854

RESUMO

OBJECTIVE: Reparixin is an inhibitor of CXCR1/2 chemokine receptor shown to be an effective anti-inflammatory adjuvant in a pilot clinical trial in allotransplant recipients. RESEARCH DESIGN AND METHODS: A phase 3, multicenter, randomized, double-blind, parallel-assignment study (NCT01817959) was conducted in recipients of islet allotransplants randomized (2:1) to reparixin or placebo in addition to immunosuppression. Primary outcome was the area under the curve (AUC) for C-peptide during the mixed-meal tolerance test at day 75 ± 5 after the first and day 365 ± 14 after the last transplant. Secondary end points included insulin independence and standard measures of glycemic control. RESULTS: The intention-to-treat analysis did not show a significant difference in C-peptide AUC at both day 75 (27 on reparixin vs. 18 on placebo, P = 0.99) and day 365 (24 on reparixin vs. 15 on placebo, P = 0.71). There was no statistically significant difference between treatment groups at any time point for any secondary variable. Analysis of patient subsets showed a trend for a higher percentage of subjects retaining insulin independence for 1 year after a single islet infusion in patients receiving reparixin as compared with patients receiving placebo (26.7% vs. 0%, P = 0.09) when antithymocyte globulin was used as induction immunosuppression. CONCLUSIONS: In this first double-blind randomized trial, islet transplantation data obtained with reparixin do not support a role of CXCR1/2 inhibition in preventing islet inflammation-mediated damage.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Secreção de Insulina/efeitos dos fármacos , Transplante das Ilhotas Pancreáticas , Sulfonamidas/administração & dosagem , Adolescente , Adulto , Idoso , Terapia Combinada , Diabetes Mellitus Tipo 1/tratamento farmacológico , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade , Placebos , Período Pós-Operatório , Receptores de Interleucina-8A/antagonistas & inibidores , Receptores de Interleucina-8B/antagonistas & inibidores , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacologia , Fatores de Tempo , Adulto Jovem
19.
Diabetes Care ; 43(1): 44-52, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31484666

RESUMO

OBJECTIVE: The HypoCOMPaSS study was designed to test the hypothesis that successful avoidance of biochemical hypoglycemia without compromising overall glycemic control would restore sufficient hypoglycemia awareness to prevent recurrent severe hypoglycemia in the majority of participants with established type 1 diabetes. Before starting the study, we planned to investigate associations between baseline characteristics and recurrent severe hypoglycemia over 2 years' follow-up. RESEARCH DESIGN AND METHODS: A total of 96 adults with type 1 diabetes and impaired awareness of hypoglycemia participated in a 24-week 2 × 2 factorial randomized controlled trial comparing insulin delivery and glucose monitoring modalities, with the goal of rigorous biochemical hypoglycemia avoidance. The analysis included 71 participants who had experienced severe hypoglycemia in the 12-month prestudy with confirmed absence (complete responder) or presence (incomplete responder) of severe hypoglycemia over 24 months' follow-up. RESULTS: There were 43 (61%) complete responders and 28 (39%) incomplete responders experiencing mean ± SD 1.5 ± 1.0 severe hypoglycemia events/person-year. At 24 months, incomplete responders spent no more time with glucose ≤3 mmol/L (1.4 ± 2.1% vs. 3.0 ± 4.8% for complete responders; P = 0.26), with lower total daily insulin dose (0.45 vs. 0.58 units/24 h; P = 0.01) and greater impairment of hypoglycemia awareness (Clarke score: 3.8 ± 2.2 vs. 2.0 ± 1.9; P = 0.01). Baseline severe hypoglycemia rate (16.9 ± 16.3 vs. 6.4 ± 10.8 events/person-year; P = 0.002) and fear of hypoglycemia were higher in incomplete responders. Peripheral neuropathy was more prevalent in incomplete responders (11 [39%] vs. 2 [4.7%]; P < 0.001) with a trend toward increased autonomic neuropathy. CONCLUSIONS: Recurrent severe hypoglycemia was associated with higher preintervention severe hypoglycemia rate, fear of hypoglycemia, and concomitant neuropathy.


Assuntos
Conscientização , Transtornos Cognitivos/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemia/induzido quimicamente , Hipoglicemia/diagnóstico , Insulina/efeitos adversos , Adolescente , Adulto , Idoso , Glicemia/análise , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Automonitorização da Glicemia , Transtornos Cognitivos/complicações , Transtornos Cognitivos/diagnóstico , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/diagnóstico , Feminino , Humanos , Hipoglicemia/psicologia , Insulina/administração & dosagem , Sistemas de Infusão de Insulina , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
20.
J Clin Endocrinol Metab ; 105(5)2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31748811

RESUMO

CONTEXT: Although diabetes affects 40% to 50% of adults with cystic fibrosis, remarkably little is known regarding the underlying mechanisms leading to impaired pancreatic ß-cell insulin secretion. Efforts toward improving the functional ß-cell deficit in cystic fibrosis-related diabetes (CFRD) have been hampered by an incomplete understanding of whether ß-cell function is intrinsically regulated by cystic fibrosis transmembrane conductance regulator (CFTR). Definitively excluding meaningful CFTR expression in human ß-cells in situ would contribute significantly to the understanding of CFRD pathogenesis. OBJECTIVE: To determine CFTR messenger ribonucleic acid (mRNA) and protein expression within ß-cells in situ in the unmanipulated human pancreas of donors without any known pancreatic pathology. DESIGN: In situ hybridization for CFTR mRNA expression in parallel with insulin immunohistochemical staining and immunofluorescence co-localization of CFTR with insulin and the ductal marker, Keratin-7 (KRT7), were undertaken in pancreatic tissue blocks from 10 normal adult, nonobese deceased organ donors over a wide age range (23-71 years) with quantitative image analysis. RESULTS: CFTR mRNA was detectable in a mean 0.45% (range 0.17%-0.83%) of insulin-positive cells. CFTR protein expression was co-localized with KRT7. One hundred percent of insulin-positive cells were immunonegative for CFTR. CONCLUSIONS: For the first time, in situ CFTR mRNA expression in the unmanipulated pancreas has been shown to be present in only a very small minority (<1%) of normal adult ß-cells. These data signal a need to move away from studying endocrine-intrinsic mechanisms and focus on elucidation of exocrine-endocrine interactions in human cystic fibrosis.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Células Secretoras de Insulina/metabolismo , Pâncreas/metabolismo , Adulto , Idoso , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos , Autopsia , Contagem de Células , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Feminino , Furões , Técnicas de Inativação de Genes , Humanos , Células Secretoras de Insulina/patologia , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Adulto Jovem
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