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J Nerup

Publications and source records attributed to J Nerup.

At least 127 records · Page 7Linked to original sources
PubMed1993

No independent association between a tumor necrosis factor-alpha promotor region polymorphism and insulin-dependent diabetes mellitus.

Several studies have implicated tumor necrosis factor (TNF)-alpha in the pathogenesis of insulin-dependent diabetes mellitus (IDDM). In the present study we analyzed the first reported TNF-alpha gene polymorphism in relation to IDDM. We have made frequence analysis and tested in vitro lipopolysaccharide (LPS)-induced TNF-alpha secretion. A significant difference in allele frequency was observed between patients and controls (p = 0.03). However, a very strong association of the uncommon TNF2 allele was observed with the HLA-B8, -DR3 alleles. The relative risk (RR) of TNF2 was 2.2 compared to a RR of 3.1 for DR3. One reason for this difference was the identification of the TNF1 allele on the otherwise strongly IDDM-associated HLA-DR3 haplotype: DQB1*0201, DQA1*0501, DRB1*0301, TNFc2, TNFB*2, TNFa1, TNFb5, B18. Thus, the IDDM-associated TNF2 allele had no DR3-independent value as a disease marker. The LPS-induced TNF-alpha production by human monocytes in relation to genotypes demonstrated that TNF1/2 heterozygous individuals had higher, though not statistically significantly (p = 0.08) levels than TNF1-homozygous subjects. However, this difference was rather small, unlikely to be of biological significance and based on the present material we cannot establish the functional importance of this polymorphism.

Adolescent↗
PubMed1993

A nationwide population-based study of the familial aggregation of type 1 (insulin-dependent) diabetes mellitus in Denmark. Danish Study Group of Diabetes in Childhood.

The objective of the present study was to assess the prevalence of familial aggregation of Type 1 (insulin-dependent) diabetes mellitus among Danish families with a diabetic child aged 20 years or less and to compare epidemiological data for familial and sporadic cases. We attempted to identify all patients with Type 1 diabetes aged 0-19 years in Denmark treated at paediatric departments or at departments of internal medicine. This comprises more than 98% of all patients with Type 1 diabetes in this age group. Patients were identified through the local diabetic out-patient registry and asked to complete a questionnaire regarding data on diabetes onset and family history. Of 1574 probands 1419 agreed to participate (90.2%). Additional cases of Type 1 diabetes were found in 171 families (12.8%). Of these 115 were parent-offspring affected families, and in 56 families at least two siblings had Type 1 diabetes and healthy parents. Significant correlation in age at onset of Type 1 diabetes in concordant siblings was observed (r = 0.5, p = 0.0004). Significantly more probands had an affected father with Type 1 diabetes than a mother affected (p < 0.0001). Heterogeneity in epidemiological characteristics was observed between familial and sporadic cases, i.e. familial index cases were younger at onset of the disease, their parents were younger at birth of the index case, and there was no difference in gender of familial cases in contrast to sporadic cases where significantly more males were found. Over a 4-year period (1986-1989) an increasing trend in incidence was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Differential interleukin-1 receptor antagonism on pancreatic beta and alpha cells. Studies in rodent and human islets and in normal rats.

The monokines interleukin-1 alpha and -beta have been implicated as effector molecules in the immune-mediated pancreatic beta-cell destruction leading to insulin-dependent diabetes mellitus. Here we investigated the effects of interleukin-1 receptor antagonism on insulin and glucagon release of rat, mouse and human islets exposed to recombinant human interleukin-1 beta, and on interleukin-1 beta induced changes in blood glucose, serum insulin and serum glucagon levels in Wistar Kyoto rats. The interleukin-1 receptor antagonist reduced the co-mitogenic effect of interleukin-1 beta on mouse and rat thymocytes with a 50% inhibitory concentration of 10- and 100-fold molar excess, respectively. Complete inhibition was obtained with a 100-1,000-fold molar excess. However, at a 100-fold molar excess the interleukin-1 receptor antagonist did not antagonise the potentiating effect of interleukin-1 beta on rat islet insulin accumulation during 3 and 6 h of exposure or of interleukin-1 beta-induced inhibition of insulin release after 24 h. In contrast, interleukin-1 beta-stimulated islet glucagon release was completely antagonised by a 100-fold molar excess of interleukin-1 receptor antagonist. A 10,000-fold molar excess of interleukin-1 receptor antagonist was needed to antagonise interleukin-1 beta stimulatory and inhibitory effects on rat beta-cell function in vitro. A 100-fold excess of interleukin-1 receptor antagonist could not counteract interleukin-1 beta effects on mouse and human beta cells, excluding species difference in the efficacy of the human interleukin-1 receptor antagonist.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Involvement of interleukin 1 and interleukin 1 antagonist in pancreatic beta-cell destruction in insulin-dependent diabetes mellitus.

In this review we propose that the balance between the action of interleukin 1 (IL-1) and its natural antagonist IL-1ra on the level of the insulin-producing pancreatic beta-cell may play a decisive role in the pathogenesis of insulin-dependent diabetes mellitus (IDDM). We argue that IL-1 potentiated by other cytokines (tumor necrosis factor alpha, interferon gamma) is an important effector molecule involved in both early and late events in the immune-mediated process that leads to beta-cell destruction and IDDM. We also point out that surprisingly high molar excesses of IL-1ra over IL-1 are necessary to block the action of IL-1 on islet beta-cells compared to islet alpha-cells in vitro and in animals. We suggest that the selectivity of beta-cell destruction in IDDM may be conferred on several levels: (1) homing of beta-cell antigen specific T cells, (2) targeted delivery of cytokines by lymphocytic and monocytic cells beta-cells, (3) high molar excesses of IL-1ra over IL-1 needed to prevent IL-1 mediated beta-cell toxicity, (4) increased beta-cell sensitivity to free nitric oxide and oxygen radical formation induced by IL-1 and (5) inadequate oxidative stress response by beta-cells to cytokines. Further studies are needed to establish the in vivo role of an imbalance between the amounts of IL-1 and IL-1ra produced relative to their action in the pathogenesis of IDDM.

Animals↗
PubMed1993

Pancreatic beta-cell function and interleukin-1 beta in plasma during the acute phase response in patients with major burn injuries.

Animal experiments demonstrate that interleukin-1 beta (IL-1 beta) is beta-cell cytotoxic in vitro and inhibits insulin secretion in vivo. However, it is unknown if IL-1 beta affects beta-cell function in man. Since IL-1 beta and other cytokines are main mediators of the acute phase response, the objectives of the present study were to examine beta-cell function in patients with major burn injuries, and to test if changes in beta-cell function correlated to systemic levels of IL-1 beta and tumour necrosis factor alpha (TNF alpha). We established and validated an IL-1 beta assay measuring free and protein bound IL-1 beta; protein bound IL-1 beta was detached from the IL-1 beta specific binding protein by acidification, rendering it accessible for the employed antibody. The IL-1 beta specific binding protein (43-60 kDa) was found in serum and plasma from all tested patients and normal subjects. Survivors of burn injuries had a stimulated beta-cell function, whereas non-survivors had an impaired beta-cell function as indicated by an increased plasma concentration of proinsulin, and an increased proinsulin/insulin ratio. In addition, non-survivors had significantly increased plasma levels of IL-1 beta. However, we could not demonstrate any correlation between C-peptide, proinsulin, insulin or proinsulin/insulin ratio and plasma concentration of IL-1 beta. In conclusion, beta-cell function abnormalities are evident in patients with major burn injuries, and a high plasma level of IL-1 beta correlates with a fatal outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute-Phase Reaction↗
PubMed1993

Deficiency of erythropoietin is not responsible for the anaemia associated with cyclosporin treatment of insulin-dependent diabetes mellitus. Canadian-European Randomized Control Trial Group.

OBJECTIVES: To explore the possible pathogenetic role of erythropoietin (EPO) in the anaemia associated with cyclosporin (Cs) in newly diagnosed patients with insulin-dependent diabetes mellitus (IDDM). DESIGN: A multicentre randomized placebo controlled prospective trial of Cs immunosuppression for 12 months in IDDM patients. SETTING: Patients were recruited from the out-patient clinics of diabetes centres in Europe and Canada. SUBJECTS: Patients 9-35 years old with a clinical diagnosis of ketonuric IDDM entering less than 6 weeks after diagnosis. 188 patients were originally recruited; 105 patients completed the investigation, 52 patients being treated with Cs, and 53 patients receiving placebo. INTERVENTIONS: Random allocation to receive either Cs or placebo. The initial dose of Cs was 10 mg kg-1 BW day-1. Therapy was maintained for 12 months. MAIN OUTCOME MEASURES: B-Haemoglobin, s-creatinine, and s-EPO concentrations were monitored before, during and after therapy with either Cs or placebo. RESULTS: Blood-haemoglobin (Hgb) fell from 8.5 +/- 0.8 to a nadir of 7.8 +/- 0.9 mmol l-1 at 6 months (P < 0.0001) in IDDM patients treated with Cs but not in the placebo patients (8.5 +/- 0.8 to 8.8 +/- 0.9 mmol l-1, NS). The mean serum EPO levels remained unaltered throughout the 6-month period of Cs and placebo therapy. No significant differences in serum EPO levels between Cs and placebo-treated diabetic patients were found after 6 months of treatment. CONCLUSIONS: The light anaemia associated with Cs therapy in IDDM patients is not related to an insufficient production of EPO, but is caused by other, as yet unknown mechanisms, unrelated to the nephrotoxic action of this drug.

Adolescent↗
PubMed1993

Polymorphic analysis of the human MHC-linked heat shock protein 70 (HSP70-2) and HSP70-Hom genes in insulin-dependent diabetes mellitus (IDDM).

In the present study we characterized the frequencies of two polymorphisms within the MHC-linked heat shock protein (HSP) 70 genes in patients with insulin-dependent diabetes mellitus (IDDM) (n = 114) and healthy control individuals (n = 110). Significant differences in genotype and allelic frequencies were observed for both polymorphisms between randomly selected patients and controls. However, for the HSP70-2 polymorphisms this was solely due to linkage disequilibrium with DR3. The rate HSP70-Hom 2-allele was significantly more frequent in controls than in patients. It showed strong association with certain tumour necrosis factor (TNF) (class III) and HLA-B and -A (class I) alleles independent of HLA-DQ and -DR alleles. By typing 257 individuals from 55 IDDM multiple-case families two extended MHC-haplotypes, including class II-, TNF- and class I-markers, carrying the rare HSP70-Hom allele were defined. One was only transmitted to diabetic offspring, whereas the other was only transmitted to unaffected offspring. The functional implication of the polymorphism in the heat shock-inducible HSP70-2 gene was analysed by studying HSP70-2 mRNA expression after heat shock in peripheral blood mononuclear cells from individuals with different HSP70-2 genotypes. Preliminary data showed that individuals homozygous for the PstI 8.5-kb allele consistently had slightly lower expression than heterozygous and 9.0-kb homozygous individuals.

Adult↗
PubMed1993

Diabetes mellitus in cystic fibrosis: genetic and immunological markers.

Family history, as well as genetic and immunological markers of diabetes mellitus, were studied in cystic fibrosis (CF) patients with and without diabetes mellitus. Positive family history of diabetes mellitus in first-degree relatives was found in only 6 of 210 (3%) CF patients, with no difference between non-diabetic and diabetic patients. The frequency distributions of the HLA types DR3, DR4 and DR3/4, which normally confer susceptibility to insulin-dependent diabetes mellitus and of HLA-DR2, which normally confers resistance to insulin-dependent diabetes mellitus, were not different in non-diabetic CF patients, diabetic CF patients and normal subjects. The genotypic frequencies of tumor necrosis factor-beta and of heat shock protein 70, located within the HLA region on chromosome 6, in CF patients with diabetes were not different from those in patients with insulin-dependent diabetes mellitus, while non-diabetic CF patients and normal subjects shared other patterns. The frequencies of the interleukin-1 beta alleles, located on chromosome 2, were not different in non-diabetic and diabetic CF patients, insulin-dependent diabetic patients and normal subjects. Islet cell cytoplasmic antibodies, measured before, at and after the diagnosis of diabetes in 33 diabetic CF patients and in 32 matched non-diabetic CF patients, were detected in only 2 of 236 (0.8%) serum samples: in a pre-diabetic patient and in a non-diabetic control patient. Birth weights were not different in diabetic and non-diabetic CF patients, arguing against the importance of the intrauterine environment as a determinant in the transmission of diabetes mellitus in CF patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

A manganese superoxide dismutase (SOD2) gene polymorphism in insulin-dependent diabetes mellitus.

Interleukin 1 (IL-1) is selectively cytotoxic to the insulin producing beta cell of pancreatic islets. This effect may be due to IL-1 induced generation of reactive oxygen species and nitric oxide. Since beta cells contain low amounts of the superoxide radical scavenger enzyme manganese superoxide dismutase (MnSOD), this may leave beta cells more susceptible to IL-1 than other cell types. Genetic variation in the MnSOD locus could reflect differences in scavenger potential. We, therefore, studied possible restriction fragment length polymorphisms (RFLPs) of this locus in patients with insulin-dependent diabetes mellitus (IDDM) (n = 154) and control individuals (n = 178). TaqI revealed a double diallelic RFLP in patients as well as in controls. No overall difference in allelic or genotype frequencies were observed between IDDM patients and control individuals (p = 0.11) and no significant association of any particular RFLP pattern with IDDM was found. Structurally polymorphic MnSOD protein variants with altered activities have been reported. If genetic variation results in MnSOD variants with reduced activities, the MnSOD locus may still be a candidate gene for IDDM susceptibility. Whether the RFLPs reported in this study reflects differences in gene expression level, protein level and/or specific activity of the protein is yet to be studied.

Alleles↗
PubMed1993

Pancreas and gut hormone responses to oral glucose and intravenous glucagon in cystic fibrosis patients with normal, impaired, and diabetic glucose tolerance.

Pancreatic and gut hormone responses to oral glucose, and insulin sensitivity were studied in cystic fibrosis patients with normal (N = 14), impaired (N = 4), and diabetic (N = 12) glucose tolerance, and in 10 control subjects, and beta cell responses to oral glucose and intravenous glucagon were compared. Compared to control subjects, initial insulin and C-peptide responses to oral glucose were lower in all patient groups, and decreased with decreasing glucose tolerance. Insulin sensitivity in patients with impaired and diabetic glucose tolerance was lower than in control subjects. The 6 min post-glucagon C-peptide concentration was positively correlated with the initial insulin response to oral glucose. Fasting levels of pancreatic polypeptide, pancreatic glucagon, total glucagon, glucagon-like peptide-1 7-36 amide, and gastric inhibitory polypeptide were normal in all patient groups. Following oral glucose, pancreatic polypeptide responses were absent in all patients, suppressibility of pancreatic glucagon secretion was increasingly impaired with decreasing glucose tolerance, and gut hormone levels were normal. In conclusion, at cystic fibrosis (a) insulin secretion is impaired even when glucose tolerance and insulin sensitivity are within the normal range, (b) the glucagon test gives valid estimates of residual beta cell function, (c) pancreatic polypeptide response to oral glucose is absent, (d) glucagon suppressibility decreases with decreasing glucose tolerance, and (e) the enteroinsular axis is intact.

Administration, Oral↗
PubMed1992

Multipoint linkage analysis of the short arm of chromosome 11 in non-insulin dependent diabetes including maturity onset diabetes of youth.

Members of three families with maturity onset diabetes of youth (MODY) and seven with "common" type 2 diabetes were typed for six DNA markers (H-RAS, INS, HBBC, PTH, CALC1, CAT) on the short arm of chromosome 11. Using conventional pairwise linkage analysis, close linkage in the MODY families was excluded for all six markers. By multipoint analysis and a genetic map of the short arm of chromosome 11, MODY was excluded from a region of at least 35 and up to 60 centiMorgans (cM) on the short arm of chromosome 11. Multipoint analysis in the type 2 families also excludes linkage to the INS, H-RAS region of at least 3 and up to 30 cM. This study using multipoint linkage analysis in non-insulin dependent diabetes provides strong evidence against a role for mutations in or around the insulin gene in the causation of MODY or type 2 diabetes in the families studied.

Chromosomes, Human, Pair 11↗
PubMed1992

Repetitive in vivo treatment with human recombinant interleukin-1 beta modifies beta-cell function in normal rats.

It is unknown whether interleukin-1 exerts a bimodal effect on Beta-cell function in vivo, and whether interleukin-1 has a diabetogenic action in normal animals. We therefore studied: (a) acute effects 2 h after an intraperitoneal bolus injection of 4 micrograms of recombinant human interleukin-1 beta per kg body weight on blood glucose, plasma levels of insulin, glucagon and corticosterone in Wistar Kyoto rats, either untreated or pre-treated with 4 micrograms/kg of interleukin-1 daily for 3 or 5 days; (b) the cumulative effects of repetitive intraperitoneal injections of 4 micrograms/kg interleukin-1 on blood glucose, glucose tolerance, plasma levels of insulin, glucagon and corticosterone, pancreatic insulin content and pancreatic ultrastructure; and (c) blood glucose and plasma concentrations of insulin, glucagon and corticosterone 10 h after the last of five intraperitoneal injections of interleukin-1, at which time point the inhibitory effect of short-term interleukin-1 exposure on insulin secretion reaches its nadir in vitro. A single injection of 4 micrograms/kg of interleukin-1 caused a slight, but significant lowering of blood glucose 2 h after interleukin-1 injection with no significant changes in plasma insulin and in spite of increases in plasma glucagon and corticosterone. A lowering of blood glucose 2 h after interleukin-1 administration was reproduced with 40, but not 0.4 micrograms/kg of interleukin-1, and was also seen in interleukin-1 pre-treated rats. Two hours after the fifth injection of interleukin-1, intraperitoneal glucose tolerance was impaired with elevated plasma insulin and corticosterone levels and increased pancreatic insulin content, indicating a state of insulin resistance.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Influence of the development of diabetes mellitus on clinical status in patients with cystic fibrosis.

The impact of pre-diabetes on clinical status was retrospectively studied in 38 cystic fibrosis (CF) patients with diabetes mellitus (DM) and 38 non-diabetic CF patients (control patients), matched in pairs for age, sex, and chronic Pseudomonas aeruginosa lung infection. Quarterly parameters of CF clinical status were collected for 6 years prior to the diagnosis of DM in the index case. Compared to the control patients, decreases in body weight, body mass index (BMI), forced expiratory volume in 1s (FEV1), and forced vital capacity (FVC) and an increase in the daily intake of pancreatic enzyme capsules were found in the pre-diabetic patients. Statistically significant differences in body weight, BMI, FEV1, FVC, and intake of pancreatic enzyme capsules between pre-diabetic and control patients emerged 4, 4, 1.25, 3 and 4.5 years prior to the diagnosis of DM, respectively. The number of lung infections did not differ between the two groups of patients. Thus, when DM develops in CF patients, an insidious decline in overall clinical status is observed for years prior to its diagnosis. Whether clinical deterioration in CF leads to DM, or pre-diabetes results in declining CF clinical status is presently unknown. Accumulating evidence suggests that the latter may be the case since insulin therapy seems to improve lung function in CF.

Adolescent↗
PubMed1992

A TaqI polymorphism in the human interleukin-1 beta (IL-1 beta) gene correlates with IL-1 beta secretion in vitro.

In the present study we searched for restriction fragment length polymorphisms (RFLP) in the human interleukin-1 beta (IL-1 beta) gene and for correlations to monocyte (Mo) function in non-related healthy donors and insulin-dependent diabetic patients. We demonstrated a diallelic polymorphism with the restriction enzyme TaqI consisting of fragments of 9.4 kb and 13.4 kb. No differences in allele or genotype frequencies of this RFLP were observed between randomly selected controls and randomly selected patients with insulin-dependent diabetes mellitus (IDDM). However, when analysing IDDM patients negative for HLA-DR3 and -DR4, our data demonstrate that the 13.4 kb allele is more frequent in this group compared to a matched control group. The functional impact of this RFLP was studied by analysing in vitro stimulated Mo IL-1 beta response. An IL-1 beta allele dosage effect on secretory capacity was observed after LPS-stimulation: 13.4/13.4 kb homozygous individuals secreted significantly more IL-1 beta than 9.4/13.4 kb heterozygous individuals, who secreted significantly more than 9.4/9.4 kb homozygous individuals. Analyses of supernatants from LPS-stimulated Mo cultures from individuals with each TaqI IL-1 beta genotype revealed no differences in the mouse thymocyte co-stimulatory assay when compared on a molar basis, indicating that the TaqI polymorphism gave rise only to quantitative differences in expression levels and probably not to a mutant IL-1 beta.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Tumour necrosis factor-beta gene RFLP alleles in Finnish IDDM haplotypes. The Childhood Diabetes in Finland (DiMe) Study Group.

The genes located between class II and class I HLA genes including polymorphic tumour necrosis factor (TNF) genes may contribute to the disease susceptibility in IDDM. Restriction fragment polymorphisms of the TNF-beta gene have been found to be fixed in the major IDDM susceptibility haplotypes, the B62,DR4 haplotype being associated with the 10.5-kb fragment and the B8,DR3 haplotype with a 5.5-kb fragment. We studied this TNF polymorphism in a sample of diabetic families. In all IDDM-associated haplotypes (n = 129) the 5.5-kb allele was more frequent than in haplotypes found only in healthy family members (n = 112) (58.1% versus 40.2%, P < 0.01). Among IDDM haplotypes the B62,DR4 haplotype was characterized by the 10.5-kb TNF fragment, whereas two other common Finnish IDDM-associated DR4 haplotypes--A24,B39,DR4 and A2,B56,DR4--had the 5.5-kb TNF fragment. Both IDDM-associated and non-associated DR3 positive haplotypes were linked to the 5.5-kb fragment. The distribution of various combinations of TNF alleles in IDDM probands (n = 63) did not differ from that expected according to the Hardy-Weinberg distribution. Our results indicate that the 10.5-kb allele of TNF-beta gene as such is not a risk factor contributing to DR4/DQ8-associated susceptibility. Alternatively, there may be heterogeneity in pathogenetic effector mechanisms.

Alleles↗