![]() ; ; et al in Molecular and Cellular Endocrinology (2016), 419 The study aimed to explore the role of ERBB3 in type 1 diabetes (T1D). We examined whether genetic variation of ERBB3 (rs2292239) affects residual β-cell function in T1D cases. Furthermore, we examined ... [more ▼] The study aimed to explore the role of ERBB3 in type 1 diabetes (T1D). We examined whether genetic variation of ERBB3 (rs2292239) affects residual β-cell function in T1D cases. Furthermore, we examined the expression of ERBB3 in human islets, the effect of ERBB3 knockdown on apoptosis in insulin-producing INS-1E cells and the genetic and regulatory architecture of the ERBB3 locus to provide insights to how rs2292239 may confer disease susceptibility. rs2292239 strongly correlated with residual β-cell function and metabolic control in children with T1D. ERBB3 locus associated lncRNA (NONHSAG011351) was found to be expressed in human islets. ERBB3 was expressed and down-regulated by pro-inflammatory cytokines in human islets and INS-1E cells; knockdown of ERBB3 in INS-1E cells decreased basal and cytokine-induced apoptosis. Our data suggests an important functional role of ERBB3 and its potential regulators in the β-cells and may constitute novel targets to prevent β-cell destruction in T1D. © 2015 Elsevier Ireland Ltd. [less ▲] Detailed reference viewed: 174 (2 UL)![]() ; ; et al in Pediatric Diabetes (2015), 16(6), 402-406 Modern insulin regimens for the treatment of type 1 diabetes are highly individualized. The concept of an individually tailored medicine accounts for a broad variety of different insulin regimens applied ... [more ▼] Modern insulin regimens for the treatment of type 1 diabetes are highly individualized. The concept of an individually tailored medicine accounts for a broad variety of different insulin regimens applied. Despite clear recommendations for insulin management in children and adolescents with type 1 diabetes there is little distinctiveness about concepts and the nomenclature is confusing. Even among experts similar terms are used for different strategies. The aim of our review--based on the experiences of the Hvidoere Study Group (HSG)--is to propose comprehensive definitions for current insulin regimens reflecting current diabetes management in childhood and adolescence. The HSG--founded in 1994--is an international group representing 24 highly experienced pediatric diabetes centers, from Europe, Japan, North America and Australia. Different benchmarking studies of the HSG revealed a broad variety of insulin regimens applied in each center, respectively. Furthermore, the understanding of insulin regimens has been persistently different between the centers since more than 20 yr. Not even the terms 'conventional' and 'intensified therapy' were used consistently among all members. Besides the concepts 'conventional' and 'intensified', several other terms for the characterization of insulin regimens are in use: Basal Bolus Concept (BBC), multiple daily injections (MDI), and flexible insulin therapy (FIT) are most frequently used, although none of these expressions is clearly or consistently defined. The proposed new classification for insulin management will be comprehensive, simple, and catchy. Currently available terms were included. This classification may offer the opportunity to compare therapeutic strategies without the currently existing confusion on the insulin regimen. [less ▲] Detailed reference viewed: 127 (1 UL)![]() ; De Beaufort, Carine ![]() in Pediatric Diabetes (2013), 14(7), 473-480 [No abstract available] Detailed reference viewed: 157 (0 UL)![]() ; ; et al in Pediatric Diabetes (2012), 13(1), 51-58 Objective: Proinsulin is a marker of beta-cell distress and dysfunction in type 2 diabetes and transplanted islets. Proinsulin levels are elevated in patients newly diagnosed with type 1 diabetes. Our aim ... [more ▼] Objective: Proinsulin is a marker of beta-cell distress and dysfunction in type 2 diabetes and transplanted islets. Proinsulin levels are elevated in patients newly diagnosed with type 1 diabetes. Our aim was to assess the relationship between proinsulin, insulin dose-adjusted haemoglobin A1c (IDAA1C), glucagon-like peptide-1 (GLP-1), glucagon, and remission status the first year after diagnosis of type 1 diabetes. Methods: Juvenile patients (n = 275) were followed 1, 6, and 12 months after diagnosis. At each visit, partial remission was defined as IDAA1C ≤9%. The patients had a liquid meal test at the 1-, 6-, and 12-month visits, which included measurement of C-peptide, proinsulin, GLP-1, glucagon, and insulin antibodies (IA). Results: Patients in remission at 6 and 12 months had significantly higher levels of proinsulin compared to non-remitting patients (p < 0.0001, p = 0.0002). An inverse association between proinsulin and IDAA1C was found at 1 and 6 months (p = 0.0008, p = 0.0022). Proinsulin was positively associated with C-peptide (p < 0.0001) and IA (p = 0.0024, p = 0.0068, p < 0.0001) at 1, 6, and 12 months. Glucagon (p < 0.0001 and p < 0.02) as well as GLP-1 (p = 0.0001 and p = 0.002) were significantly lower in remitters than in non-remitters at 6 and 12 months. Proinsulin associated positively with GLP-1 at 1 month (p = 0.004) and negatively at 6 (p = 0.002) and 12 months (p = 0.0002). Conclusions: In type 1 diabetes, patients in partial remission have higher levels of proinsulin together with lower levels of GLP-1 and glucagon compared to patients not in remission. In new onset type 1 diabetes proinsulin level may be a sign of better residual beta-cell function. © 2011 John Wiley & Sons A/S. [less ▲] Detailed reference viewed: 129 (0 UL)![]() ; ; et al in Autoimmunity (2011), 44(8), 616-623 Autoantibodies against the newly established autoantigen in type 1 diabetes, zinc transporter 8, ZnT8, are presented as two types, ZnT8RAb and ZnT8WAb. The rs13266634 variant of the SLC30A8 gene has ... [more ▼] Autoantibodies against the newly established autoantigen in type 1 diabetes, zinc transporter 8, ZnT8, are presented as two types, ZnT8RAb and ZnT8WAb. The rs13266634 variant of the SLC30A8 gene has recently been found to determine the type of ZnT8Ab. The aim of this study was to explore the impact of this genetic variant and the ZnT8Ab on the residual beta-cell function during disease progression the first year after disease diagnosis in children with newly diagnosed type 1 diabetes. This cohort consists of 257 children aged < 16 years, all patients were newly diagnosed with type 1 diabetes. A Boost-test was carried out at 1, 6, and 12 months to characterize the residual beta-cell function. Carriers of the CC and CT genotype groups of the rs13266634 SNP of the SLC30A8 gene had higher stimulated C-peptide levels the first year after onset compared with those of the TT genotype group (29%, p = 0.034). CC genotype carriers were highly associated with the presence of ZnT8RAb subtype during disease progression (compared with TT, p < 0.0001). On the other hand, the TT genotype was associated with the presence of ZnT8WAb subtype during disease progression (compared with CC, p < 0.0001).The C allele of the SLC30A8 gene is associated with preserved beta-cell function in type 1 diabetes patients. The genetic determination of the rs13266634 variant on the ZnT8Ab specificity is sustained the first 12 months after the diagnosis of type 1 diabetes in a pediatric cohort. © 2011 Informa UK, Ltd. [less ▲] Detailed reference viewed: 52 (0 UL)![]() ; ; et al in BMC Endocrine Disorders (2010), 10 Background: To investigate disease progression the first 12 months after diagnosis in children with type 1 diabetes negative (AAB negative) for pancreatic autoantibodies [islet cell autoantibodies(ICA ... [more ▼] Background: To investigate disease progression the first 12 months after diagnosis in children with type 1 diabetes negative (AAB negative) for pancreatic autoantibodies [islet cell autoantibodies(ICA), glutamic acid decarboxylase antibodies (GADA) and insulinoma-associated antigen-2 antibodies (IA-2A)]. Furthermore the study aimed at determining whether mutations in KCNJ11, ABCC8, HNF1A, HNF4A or INS are common in AAB negative diabetes.Materials and methods: In 261 newly diagnosed children with type 1 diabetes, we measured residual β-cell function, ICA, GADA, and IA-2A at 1, 6 and 12 months after diagnosis. The genes KCNJ11, ABCC8, HNF1A, HNF4A and INS were sequenced in subjects AAB negative at diagnosis. We expressed recombinant K-ATP channels in Xenopus oocytes to analyse the functional effects of an ABCC8 mutation.Results: Twenty-four patients (9.1%) tested AAB negative after one month. Patients, who were AAB-negative throughout the 12-month period, had higher residual β-cell function (P = 0.002), lower blood glucose (P = 0.004), received less insulin (P = 0.05) and had lower HbA1c(P = 0.02) 12 months after diagnosis. One patient had a heterozygous mutation leading to the substitution of arginine at residue 1530 of SUR1 (ABCC8) by cysteine. Functional analyses of recombinant K-ATP channels showed that R1530C markedly reduced the sensitivity of the K-ATP channel to inhibition by MgATP. Morover, the channel was highly sensitive to sulphonylureas. However, there was no effect of sulfonylurea treatment after four weeks on 1.0-1.2 mg/kg/24 h glibenclamide.Conclusion: GAD, IA-2A, and ICA negative children with new onset type 1 diabetes have slower disease progression as assessed by residual beta-cell function and improved glycemic control 12 months after diagnosis. One out of 24 had a mutation in ABCC8, suggesting that screening of ABCC8 should be considered in patients with AAB negative type 1 diabetes. © 2010 Pörksen et al; licensee BioMed Central Ltd. [less ▲] Detailed reference viewed: 108 (0 UL)![]() ; ; et al in Pediatric Diabetes (2010), 11(4), 218-226 Objective: To identify predictors of residual beta-cell function and glycemic control during the first 12 months after the diagnosis of type 1 diabetes (T1D).Subjects and Methods: Clinical information and ... [more ▼] Objective: To identify predictors of residual beta-cell function and glycemic control during the first 12 months after the diagnosis of type 1 diabetes (T1D).Subjects and Methods: Clinical information and blood samples were collected from 275 children. HbA1c, antibodies, HLA typing and mixed meal-stimulated C-peptide levels 1, 6, and 12 months after diagnosis were analyzed centrally.Results: Mean age at diagnosis was 9.1 yr. DKA with standard bicarbonate <15 mmol/L was associated with significantly poorer residual beta-cell function 1 (p = 0.004) and 12 months (p = 0.0003) after diagnosis. At 12 months, the decline in stimulated C-peptide levels compared with the levels at 1 month was 69% in the youngest age group and 50% in patients 10 yr and above (p < 0.001). Stimulated C-peptide at 12 months was predicted by younger age (p < 0.02) and bicarbonate levels at diagnosis (p = 0.005), and by stimulated C-peptide (p < 0.0001), postmeal blood glucose (p = 0.0004), insulin antibodies (IA; p = 0.02) and glutamic acid decarboxylase antibodies (GADA; p = 0.0004) at 1 month. HbA1c at 12 months was predicted by HbA1c at diagnosis (p < 0.0001), GADA at 1 month (p = 0.01), and non-white Caucasian ethnicity (p = 0.002).Conclusions: Younger age, ketoacidosis at diagnosis, and IA and GADA 1 month after diagnosis were the strongest explanatory factors for residual beta-cell function at 12 months. Glycemic control at 12 months was influenced predominantly by ethnicity, HbA1c at diagnosis, and GADA at 1 month. © 2009 John Wiley & Sons A/S. [less ▲] Detailed reference viewed: 122 (1 UL)![]() ; ; De Beaufort, Carine ![]() in Pediatric Diabetes (2010), 11(4), 271-278 Objective: To evaluate glycaemic targets set by diabetes teams, their perception by adolescents and parents, and their influence on metabolic control.Methods: Clinical data and questionnaires were ... [more ▼] Objective: To evaluate glycaemic targets set by diabetes teams, their perception by adolescents and parents, and their influence on metabolic control.Methods: Clinical data and questionnaires were completed by adolescents, parents/carers and diabetes teams in 21 international centres. HbA1c was measured centrally.Results: A total of 2062 adolescents completed questionnaires (age 14.4 ± 2.3 yr; diabetes duration 6.1 ± 3.5 yr). Mean HbA 1c = 8.2 ± 1.4% with significant differences between centres (F = 12.3; p < 0.001) range from 7.4 to 9.1%. There was a significant correlation between parent (r = 0.20) and adolescent (r = 0.21) reports of their perceived ideal HbA1c and their actual HbA1c result (p < 0.001), and a stronger association between parents' (r = 0.39) and adolescents' (r = 0.4) reports of the HbA1c they would be happy with and their actual HbA1c result. There were significant differences between centres on parent and adolescent reports of ideal and happy with HbA1c (8.1 < F > 17.4;p < 0.001). A lower target HbA1c and greater consistency between members of teams within centres were associated with lower centre HbA1c (F = 16.0; df = 15; p < 0.001).Conclusions: Clear and consistent setting of glycaemic targets by diabetes teams is strongly associated with HbA1c outcome in adolescents. Target setting appears to play a significant role in explaining the differences in metabolic outcomes between centres. © 2009 John Wiley & Sons A/S. [less ▲] Detailed reference viewed: 112 (0 UL)![]() ; ; et al in Diabetes Care (2009), 32(8), 1384-1390 OBJECTIVE - To find a simple definition of partial remission in type 1 diabetes that reflects both residual β-cell function and efficacy of insulin treatment. RESEARCH DESIGN AND METHODS - A total of 275 ... [more ▼] OBJECTIVE - To find a simple definition of partial remission in type 1 diabetes that reflects both residual β-cell function and efficacy of insulin treatment. RESEARCH DESIGN AND METHODS - A total of 275 patients aged <16 years were followed from onset of type 1 diabetes. After 1, 6, and 12 months, stimulated C-peptide during a challenge was used as a measure of residual β-cell function. RESULTS - By multiple regression analysis, a negative association between stimulated C-peptide and A1C (regression coefficient -0.21, P < 0.001) and insulin dose (-0.94, P < 0.001) was shown. These results suggested the definition of an insulin dose-adjusted A1C (IDAA1C) as A1C (percent) + [4 × insulin dose (units per kilogram per 24 h)]. A calculated IDAA1C ≤9 corresponding to a predicted stimulated C-peptide >300 pmol/l was used to define partial remission. The IDAA1C ≤9 had a significantly higher agreement (P < 0.001) with residual β-cell function than use of a definition of A1C ≤7.5%. Between 6 and 12 months after diagnosis, for IDAA1C ≤9 only 1 patient entered partial remission and 61 patients ended partial remission, for A1C ≤7.5% 15 patients entered partial remission and 53 ended, for a definition of insulin dose ≤0.5 units · kg-1 · 24 h-1 5 patients entered partial remission and 66 ended, and for stimulated C-peptide (>300 pmol/l) 9 patients entered partial remission and 49 ended. IDAA1C at 6 months has good predictive power for stimulated C-peptide concentrations after both 6 and 12 months. CONCLUSIONS - A new definition of partial remission is proposed, including both glycemic control and insulin dose. It reflects residual β-cell function and has better stability compared with the conventional definitions. © 2009 by the American Diabetes Association. [less ▲] Detailed reference viewed: 139 (1 UL)![]() ; ; De Beaufort, Carine ![]() in Pediatric Diabetes (2009), 10(4), 234-239 Background: The Hvidoere Study Group on Childhood Diabetes has demonstrated persistent differences in metabolic outcomes between pediatric diabetes centers. These differences cannot be accounted for by ... [more ▼] Background: The Hvidoere Study Group on Childhood Diabetes has demonstrated persistent differences in metabolic outcomes between pediatric diabetes centers. These differences cannot be accounted for by differences in demographic, medical, or treatment variables. Therefore, we sought to explore whether differences in physical activity or sedentary behavior could explain the variation in metabolic outcomes between centers. Methods: An observational cross-sectional international study in 21 centers, with demographic and clinical data obtained by questionnaire from participants. Hemoglobin A1c (HbA1c) levels were assayed in one central laboratory. All individuals with diabetes aged 11-18 yr (49.4% female), with duration of diabetes of at least 1 yr, were invited to participate. Individuals completed a self-reported measure of quality of life (Diabetes Quality of Life - Short Form [DQOL-SF]), with well-being and leisure time activity assessed using measures developed by Health Behaviour in School Children WHO Project. Results: Older participants (p < 0.001) and females (p < 0.001) reported less physical activity. Physical activity was associated with positive health perception (p < 0.001) but not with glycemic control, body mass index, frequency of hypoglycemia, or diabetic ketoacidosis. The more time spent on the computer (r = 0.06; p < 0.05) and less time spent doing school homework (r = -0.09; p < 0.001) were associated with higher HbA1c. Between centers, there were significant differences in reported physical activity (p < 0.001) and sedentary behavior (p < 0.001), but these differences did not account for center differences in metabolic control. Conclusions: Physical activityis strongly associated with psychological well-being but has weak associations with metabolic control. Leisure time activity is associated with individual differences in HbA1c but not with intercenter differences. © 2009 John Wiley & Sons A/S. [less ▲] Detailed reference viewed: 153 (0 UL)![]() ![]() ; ; De Beaufort, Carine ![]() in Diabetic Medicine: A Journal of the British Diabetic Association (2008), 25(4), 463-468 Aims: To assess the importance of family factors in determining metabolic outcomes in adolescents with Type 1 diabetes in 19 countries. Methods: Adolescents with Type 1 diabetes aged 11-18 years, from 21 ... [more ▼] Aims: To assess the importance of family factors in determining metabolic outcomes in adolescents with Type 1 diabetes in 19 countries. Methods: Adolescents with Type 1 diabetes aged 11-18 years, from 21 paediatric diabetes care centres, in 19 countries, and their parents were invited to participate. Questionnaires were administered recording demographic data, details of insulin regimens, severe hypoglycaemic events and number of episodes of diabetic ketoacidosis. Adolescents completed the parental involvement scale from the Diabetes Quality of Life for Youth - Short Form (DQOLY-SF) and the Diabetes Family Responsibility Questionnaire (DFRQ). Parents completed the DFRQ and a Parental Burden of Diabetes score. Glycated haemoglobin (HbA1c) was analysed centrally on capillary blood. Results: A total of 2062 adolescents completed a questionnaire, with 2036 providing a blood sample; 1994 parents also completed a questionnaire. Family demographic factors that were associated with metabolic outcomes included: parents living together (t = 4.1; P < 0.001), paternal employment status (F = 7.2; d.f. = 3; P < 0.001), parents perceived to be over-involved in diabetes care (r = 0.11; P < 0.001) and adolescent-parent disagreement on responsibility for diabetes care practices (F = 8.46; d.f. = 2; P < 0.001). Although these factors differed between centres, they did not account for centre differences in metabolic outcomes, but were stronger predictors of metabolic control than age, gender or insulin treatment regimen. Conclusions: Family factors, particularly dynamic and communication factors such as parental over-involvement and adolescent-parent concordance on responsibility for diabetes care appear be important determinants of metabolic outcomes in adolescents with diabetes. However, family dynamic factors do not account for the substantial differences in metabolic outcomes between centres. © 2008 The Authors. [less ▲] Detailed reference viewed: 123 (3 UL)![]() ![]() ; ; et al in European Journal of Endocrinology (2007), 156(6), 663-671 Objective: The ATP-dependent K+-channel (KATP) is critical for glucose sensing and normal glucagon and insulin secretion from pancreatic endocrine α- and β-cells. Gastrointestinal endocrine L- and K-cells ... [more ▼] Objective: The ATP-dependent K+-channel (KATP) is critical for glucose sensing and normal glucagon and insulin secretion from pancreatic endocrine α- and β-cells. Gastrointestinal endocrine L- and K-cells are also glucose-sensing cells secreting glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotrophic polypeptide (GIP) respectively. The aims of this study were to 1) investigate the expression and co-localisation of the KATP channel subunits, Kir6.2 and SUR1, in human L- and K-cells and 2) investigate if a common hyperactive variant of the Kir6.2 subunit, Glu2Lys, exerts a functional impact on glucose-sensing tissues in vivo that may affect the overall glycaemic control in children with new-onset type 1 diabetes. Design and methods: Western blot and immunohistochemical analyses were performed for expression and co-localisation studies. Meal-stimulated C-peptide test was carried out in 257 children at 1, 6 and 12 months after diagnosis. Genotyping for the Glu23Lys variant was by PCR-restriction fragment length polymorphism. Results: Kir6.2 and SUR1 co-localise with GLP-1 in L-cells and with GIP in K-cells in human ileum tissue. Children with type 1 diabetes carrying the hyperactive Glu23Lys variant had higher HbA1c at diagnosis (coefficient= 0.61%, P= 0.02) and 1 month after initial insulin therapy (coefficient= 0.30%, P=0.05), but later disappeared. However, when adjusting HbA1c for the given dose of exogenous insulin, the dose-adjusted HbA1c remained higher throughout the 12 month study period (coefficient= 0.42%, P=0.03). Conclusions: Kir6.2 and SUR1 co-localise in the gastrointestinal endocrine L- and K-cells. The hyperactive Glu2Lys variant of the KATP channel subunit Kir6.2 may cause defective glucose sensing in several tissues and impaired glycaemic control in children with type 1 diabetes. © 2007 Society of the European Journal of Endocrinology. [less ▲] Detailed reference viewed: 120 (0 UL)![]() ![]() ; ; et al in Diabetologia (2006), 49(1), 71-74 Aims/hypothesis: The insulin-dependent diabetes mellitus 2 gene (IDDM2) is a type 1 diabetes susceptibility locus contributed to by the variable number of tandem repeats (VNTR) upstream of the insulin ... [more ▼] Aims/hypothesis: The insulin-dependent diabetes mellitus 2 gene (IDDM2) is a type 1 diabetes susceptibility locus contributed to by the variable number of tandem repeats (VNTR) upstream of the insulin gene (INS). We investigated the association between INS VNTR class III alleles (-23HphIA/T) and both insulin antibody presentation and residual beta cell function during the first year after diagnosis in 257 children with type 1 diabetes. Materials and methods: To estimate C-peptide levels and autoantibody presentation, patients underwent a meal-stimulated C-peptide test 1, 6, and 12 months after diagnosis. The insulin -23HphIA/T variant was used as a marker of class III alleles and genotyped by PCR-RFLP. Results: The insulin antibody titres at 1 and 6 months were significantly lower in the class III/III and class I/III genotype groups than in the class I/I genotype group (p = 0.01). Class III alleles were also associated with residual beta cell function 12 months after diagnosis and independently of age, sex, BMI, insulin antibody titres, and HLA-risk genotype group (p = 0.03). The C-peptide level was twice as high among class III/III genotypes as in class I/I and class I/III genotypes (319 vs 131 and 166 pmol/l, p=0.01). Furthermore, the class III/III genotype had a 1.1% reduction in HbA1c after adjustment for insulin dose (p = 0.04). Conclusions/interpretation: These findings suggest a direct connection in vivo between INS VNTR class III alleles, a decreased humoral immune response to insulin, and preservation of beta cell function in recent-onset type 1 diabetes. © Springer-Verlag 2005. [less ▲] Detailed reference viewed: 198 (0 UL) |
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