Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011854 (type 1 diabetes)
 20,749 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recently, the synthetic immunomodulator Linomide (quinoline-3-carboxamide, LS 2616) was reported to prevent IDDM and insulitis in NOD mice. The mechanism for this protective effect is not known. The cytokine interleukin 1 (IL-1) may be a pathogenetic factor in the initial destruction of the beta-cells leading to IDDM. This study was undertaken to investigate the influence of Linomide on IL-1beta induced diabetogenic and hormonal changes in the rat in vivo, and on IL-1beta mediated synthesis of NO and inhibition of insulin secretion in isolated islets of Langerhans ex vivo. Normal male Wistar Kyoto rats received 4.0 microg/kg of recombinant human IL-1beta (rhIL-1beta) i.p. daily for 5 days with or without Linomide (8-9 mg/kg/day) in the drinking water. Litters of neonatal Wistar rats were pretreated for 3 days with injections of 10 mg/kg of Linomide i.p., and pancreatic islets of Langerhans were isolated for ex vivo studies. Linomide alone caused significant hypercorticosteronemia, hypoglucagonemia, lymphopenia and neutrophilia. Linomide had no effect on IL-1beta induced hyperglycemia, hyperglucagonemia, lymphopenia, neutrocytosis, or hypercorticosteronemia on day three and hypocorticosteronemia on day five. Further, Linomide did not prevent rhIL-1beta mediated reduction in insulin secretion or increase in NO synthesis ex vivo. In conclusion, Linomide does not seem to exert its protective effect on IDDM development via inhibition of interleukin 1 action on islet insulin release or NO production, but the increase in plasma corticosterone may contribute to the understanding of the immunomodulatory effects of Linomide.
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PMID:Linomide increases plasma corticosterone in normal rats, but does not prevent the inhibitory action of IL-1 on beta-cells in vivo or ex vivo. 891 32

In vitro, cytokines like interleukin-1-beta (IL-1-B) and tumour necrosis factor-alpha (TNF-A) inhibit insulin release and can destroy islet B-cells. We measured blood levels of IL-1-B, TNF-A, and islet cell antibody (ICA) in 20 children with IDDM, 20 of their non-diabetic siblings, 20 children with thalassemia major on long-term hypertransfusion therapy and iron chelation, and 10 normal age-matched children. In the non-diabetic and thalassemic children we investigated the early phase of insulin release after i.v. glucose (0.5 g/kg, 30 per cent solution) and evaluated tolerance to oral glucose (1.75 g/ kg). Circulating IL-1-B and TNF-A concentrations were significantly higher in IDDM-siblings (33.7 +/- 12.7 pg/ml and 655 +/- 165 pg/ml, respectively) v. normal children (21.1 +/- 6.4 pg/ml and 383 +/- 122 pg/ml, respectively). Thalassemic children had no detectable circulating ICA. The prevalence of ICA was 30 per cent in children with IDDM and 60 per cent of their siblings. Impaired oral glucose tolerance was detected in five children with thalassemia (25 per cent), but in none of the IDDM-siblings. The early phase of insulin release was significantly depressed in thalassemic children (peak insulin = 29.2 +/- 5.1 mIU/ml) v. normal children (52.3 +/- 9.5 mIU/ml) and IDDM-siblings (45.3 +/- 12.4 mIU/ml). It appears that thalassemic children had significantly decreased insulin secretion and impaired glucose tolerance, however, the mechanism of B-cell dysfunction is not mediated by ICA nor by cytokines.
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PMID:Interleukin-1-beta, tumour necrosis factor-alpha, islet-cell antibody, and insulin secretion in children with thalassemia major on long-term blood transfusion. 900 65

Like most cytokines, IL-1 transduces its signals for growth, differentiation and diverse cellular functions after binding to specific receptors on the cell surface. Up to now two IL-1 receptors have been reported, type I which induces signal transduction and type II which binds IL-1 but does not transduce signalling. By using the rat insulinoma RIN-5AH cell line that expresses both types of receptor mRNA, and computer-assisted binding analysis, we show that interleukin-1 beta (IL-1 beta) binds to a single class of high affinity receptors with a Kd of 155 pmol/l. The average number of receptors on adherent cell layer is calculated to be 7300 per cell. 125I-IL-1 beta binding can be competed out by unlabelled IL-1 beta. 125I-IL-1 alpha binding can be also obtained and is subject to competition by cold IL-1 alpha. Its saturation curve, however, varies within experiments due to differential receptor up-regulation. These results have also been confirmed by FACS analysis using specific antibodies to type I and II IL-1 receptors, where type I receptor antibody binds strongly to RIN-5AH cells, and type II receptor antibody shows weak staining, also due to inadequate receptor up-regulation. In order to determine whether functional signal transduction occurs via the receptors detected, it is shown that IL-1 beta is able to induce MHC class II antigen expression on the surface of the RIN cells, whereas IL-1 alpha is unable to do so, indicating different signal reception by the cells. IL-1 beta-induced class II upregulation shows moderate signs of p21ras or/and PKC dependency, whereas IL-1 alpha strongly activates both pathways that probably regulate different functions. Finally, both IL-1 alpha and beta induce nitric oxide (NO) production in a time-dependent fashion which appears to be unrelated to the signals and pathways described, but may be involved in the onset of autoimmune type 1 diabetes.
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PMID:IL-1 beta transduces different signals than IL-1 alpha leading to class II antigen expression on beta-insulinoma RIN-5AH cells through specific receptors. 902 92

Insulin-dependent diabetes mellitus is caused by an autoimmune destruction of the beta-cells in the islets of Langerhans. The cytokine interleukin 1 inhibits insulin release and is selectively cytotoxic to beta-cells in isolated pancreatic rat islets. The antigen(s) triggering the immune response as well as the intracellular mechanisms of action of interleukin 1-mediated beta-cell cytotoxicity are unknown. However, previous studies have found an association of beta-cell destruction with alterations in protein synthesis. Thus, two-dimensional (2-D) gel electrophoresis of pancreatic islet proteins may be an important tool facilitating studies of the molecular pathogenesis of insulin-dependent diabetes mellitus. 2-D gel electrophoresis of islet proteins may lead to (i) the determination of qualitative and quantitative changes in specific islet proteins induced by cytokines, (ii) the determination of the effects of agents modulating cytokine action, and (iii) the identification of primary islet protein antigen(s) initiating the immune destruction of the beta-cells. Therefore, the aim of this study was to create databases (DB) of all reproducibly detectable protein spots on 10% and 15% acrylamide 2-D gels of neonatal rat islets (10% and 15% DB), labeled under standardized culture conditions. 1235 and 557 spots were present in 5 of 5 gels in the 15% isoelectric focusing (IEF) and nonequilibrium pH gradient electrophoresis (NEPHGE) DB, respectively, whereas 995 and 378 spots were present in 5 of 5 gels in the 10% IEF and NEPHGE DB, respectively, yielding a reproducibility of spot detection between 75.2% and 91.7%. In both DBs, the average coefficient of variation of the percentage of integrated optical density (CV% of %IOD) for spots present in all gels was between 42.4% and 45.7%. When the same sample was analyzed in consecutive sets of gels on different days (interassay analysis), the average CV% of %IOD was 35.5%-36.1%. When the same sample was analyzed repeatedly in one set of gels (intra-assay analysis), the average CV% of %IOD was 30.2% in the IEF gels, while the average CV% of %IOD was 45.7% in the NEPHGE gels. Addition of interleukin-1beta (IL-1beta) to the cultures resulted in statistically significant modulation or de novo synthesis of 105 proteins in the 10% gels. In conclusion, we present the first 10% and 15% acrylamide 2-D gel protein databases of neonatal rat islets of Langerhans and demonstrate its usage to identify proteins altered in expression by IL-1beta.
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PMID:Interleukin-1beta induced changes in the protein expression of rat islets: a computerized database. 942 Jan 75

When aiming at preventing IDDM in man, knowledge of the molecular mechanisms leading to beta cell destruction may facilitate identification of new possible intervention modalities. A model of IDDM pathogenesis in man suggests that cytokines, and IL-1 in particular, are of major importance in the initial events (Nerup et al 1994) (Fig. 1). In vitro rat experiments demonstrated that rhIL-1 beta inhibits beta cell function and induces beta cell death both in isolated islets of Langerhans and in the isolated perfused pancreatic gland. With the long term goal of identifying new modalities capable of preventing IDDM in man, the aim af this review was to investigate the effects of rhIL-1 beta on beta-cell function and viability in normal rats. This review discussed 1) the pharmacokinetics of IL-1 beta in rats as the basis for choice of route of administration and dose of rhIL-1 beta, 2) the effects and molecular mechanisms of IL-1 beta on temperature and food intake used as control parameters for successful injection of rhIL-1 beta in rats, 3) the effects of one or more injection of IL-1 beta on rat beta cell function, 4) the molecular mechanisms leading to IL-1 beta induced beta cell inhibition in vivo, and some possible intervention modalities based on the molecular mechanisms, 5) the effects of IL-1 beta on spontaneous diabetes mellitus in DP BB rats, and 6) the effects and molecular mechanisms of IL-1 beta induced inhibition of thyroid epithelial cell function and aggravated thyroiditis in DP BB rats, compared to the effects of IL-1 beta on rat beta cell function. Finally, this review discussed the effects of IL-1 beta on human beta cells in vitro, and the clinical relevance of these experiments, with special reference to a clinical trial with the aim of preventing IDDM in man. The pharmacokinetic studies suggested that IL-1 beta is distributed according to a two-compartment model with a first-order elimination. Interleukin-1 beta reached all the investigated organs in the rats, was accumulated in kidneys and was excreted in the urine. The data suggested that IL-1 beta also accumulated in the islets of Langerhans. After injection of 4.0 micrograms/kg pathophysiologically relevant concentrations of rhIL-1 beta were reached and intact rhIL-1 beta persisted for up to 5 hrs in plasma. Peripheral injections of IL-1 beta dose-dependently induced fever and anorexia in rats, probably via induction of PGE2 in the brain or in peripheral tissues thereafter passing the blood-brain barrier. Nitric oxide produced by cNOS seems to be a molecular mediator of IL-1 beta induced fever but not of anorexia. Fever and anorexia are well described effects of IL-1 beta in rats, and are as such usefull control parameters of the absorption and biological activity of IL-1 beta after peripheral injection. Injections of rhIL-1 beta to normal, non-diabetes prone rats induced initial beta cell stimulation followed by inhibition, in accordance with in vitro data. Furthermore, induction of peripheral insulin resistance coincided with beta cell inhibition after one daily injection for 5 days, leading to a transient diabetes mellitus-like state, characterized by hyperglycemia and hypoinsulinemia. At this time point, electron-microscopy did not demonstrate beta cell destruction. However, IL-1 beta induced intercellularly edema and microvillous processes on the beta cells, which might be early evidence of apoptosis. The diabetes mellitus-like state was not aggravated if the daily injections were continued beyond 5 days. Daily injections of rhIL-1 beta for 2 to 4 weeks induced formation of blocking IL-1 beta-antibodies in normal rats. Hence, injections exceeding 2 weeks should only be performed using species homologous IL-1 beta. The molecular mechanism of IL-1 beta induced beta cell inhibition in rats in vivo as in vitro, are likely to involve binding of IL-1 beta to the IL-1RtI, since the IL-1RtII is considered to be a decoy receptor. (ABSTRACT TRUNCATED)
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PMID:Interleukin-1 beta induced transient diabetes mellitus in rats. A model of the initial events in the pathogenesis of insulin-dependent diabetes mellitus? 958 1

Insulin-dependent diabetes mellitus (IDDM) is a disease that results from autoimmune destruction of the insulin-producing beta-cells in the pancreatic islets of Langerhans. The autoimmune response against islet beta-cells is believed to result from a disorder of immunoregulation. According to this concept, a T helper 1 (Th1) subset of T cells and their cytokine products, i.e. Type 1 cytokines--interleukin 2 (IL-2), interferon gamma (IFNgamma), and tumor necrosis factor beta (TNFbeta), dominate over an immunoregulatory (suppressor) Th2 subset of T cells and their cytokine products, i.e. Type 2 cytokines--IL-4 and IL-10. This allows Type 1 cytokines to initiate a cascade of immune/inflammatory processes in the islet (insulitis), culminating in beta-cell destruction. Type 1 cytokines activate (1) cytotoxic T cells that interact specifically with beta-cells and destroy them, and (2) macrophages to produce proinflammatory cytokines (IL-1 and TNFalpha), and oxygen and nitrogen free radicals that are highly toxic to islet beta-cells. Furthermore, the cytokines IL-1, TNFalpha, and IFNgamma are cytotoxic to beta-cells, in large part by inducing the formation of oxygen free radicals, nitric oxide, and peroxynitrite in the beta-cells themselves. Therefore, it would appear that prevention of islet beta-cell destruction and IDDM should be aimed at stimulating the production and/or action of Type 2 cytokines, inhibiting the production and/or action of Type 1 cytokines, and inhibiting the production and/or action of oxygen and nitrogen free radicals in the pancreatic islets.
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PMID:Cytokines and their roles in pancreatic islet beta-cell destruction and insulin-dependent diabetes mellitus. 971 67

Insulin-dependent diabetes mellitus (IDDM) is not a disease of unbridled destruction. The autoimmune attack on pancreatic beta cells has two distinct stages - insulitis and diabetes - and progression of the former to the latter appears to be highly regulated. Identifying the factors controlling this transition has been difficult because it is a complex process that occurs non-universally and asynchronously. We have overcome these difficulties by coupling a simplified TCR transgenic (tg) model of IDDM and the immunosuppressive drug cyclophosphamide (CY). Young BDC2.5 TCR tg mice show insulitis but not diabetes; CY treatment provoked diabetes in 100% of animals with rapid, highly reproducible kinetics. This allowed a detailed temporal analysis of changes in cellular organization and cytokine gene expression within the lesion. The monokines IL-18, IL-12 and TNF-alpha were pivotal, their induction occurring almost immediately and their coordinate action being required for the onset of aggression. Other cytokines with direct toxicity for beta cells, including IL-1 -beta, IL-6 and IFN-gamma, were subsequently induced; in contrast, there was no cellular or molecular evidence of cell contact-mediated mechanisms of beta cell death.
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PMID:Cellular and molecular changes accompanying the progression from insulitis to diabetes. 993 6

The beta-cells in the pancreatic islets of Langerhans are the targets of autoreactive T-cells and are destroyed in type 1 diabetes. Macrophage-derived interleukin-1beta (IL-1beta) is important in eliciting beta-cell dysfunction and initiating beta-cell damage in response to microenvironmental changes within islets. In particular, IL-1beta can impair glucose-stimulated insulin production in beta-cells in vitro and can sensitize them to Fas (CD95)/FasL-triggered apoptosis. In this report, we have examined the ability to block the detrimental effects of IL-1beta by genetically modifying islets by adenoviral gene transfer to express the IL-1 receptor antagonist protein. We demonstrate that adenoviral gene delivery of the cDNA encoding the interleukin-1 receptor antagonist protein (IL-1Ra) to cultured islets results in protection of human islets in vitro against IL-1beta-induced nitric oxide formation, impairment in glucose-stimulated insulin production, and Fas-triggered apoptosis activation. Our results further support the hypothesis that IL-1beta antagonism in in situ may prevent intra-islet proinsulitic inflammatory events and may allow for an in vivo gene therapy strategy to prevent insulitis and the consequent pathogenesis of diabetes.
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PMID:Adenoviral gene transfer of the interleukin-1 receptor antagonist protein to human islets prevents IL-1beta-induced beta-cell impairment and activation of islet cell apoptosis in vitro. 1048 Jun 1

Recent reports suggest that the pancreas participates in tumor necrosis factor alpha (TNF-A) production during stress, and that the islets are predominantly responsible for such synthesis. In vitro TNF-A and interleukin 1-beta (IL-1-beta) inhibit insulin release from islet beta-cells. We measured the circulating levels of IL-1-beta, TNF-A and islet cell antibody (ICA) in 30 children with IDDM (10 of them at their first presentation), 30 of their non-diabetic siblings, and 30 normal age-matched children. In the non-diabetic children we investigated the early phase of insulin release after intravenous bolus of glucose and evaluated tolerance to oral glucose (OGTT). IL-1-beta and TNF-A concentrations were significantly higher in IDDM-siblings (31.8 +/- 7.7 pg/ml and 650 +/- 155 pg/ml respectively) versus normal children (21.2 +/- 6.4 pg/ml and 383 +/- 122 pg/ml respectively). IL-1-beta and TNF-A concentrations did not differ significantly between the diabetic children and healthy age-matched controls. ICA were detected in 60% of the recently diagnosed diabetic children vs. 30% of those with longer duration of diabetes (3.1 +/- 1.2 years). Despite the significantly high prevalence of ICA in the recently diagnosed children with IDDM, their IL-1-beta and TNF-A concentrations were lower than those for the normal children. In experimental animals these cytokines can induce round cell infiltration (insulinitis) and inhibit insulin secretion by beta-cell. The presence of significantly higher concentrations of these cytokines in IDDM siblings, with high prevalence of ICA (16%), was associated with normal oral glucose tolerance and normal peak insulin response (60 +/- 10.4 mlU/ml) after i.v. glucose bolus compared to normal children (52.3 +/- 9.5 mlU/ml). However, after 2 years of follow up, one of them developed IDDM and another developed IGT but none of the normal controls developed abnormal glucose tolerance. It appears that the process of autoimmune aggression against beta-cells, and its effect on insulin release and glucose homeostasis, is a slow and chronic process. However, the production of these cytokines and consequently the degree of beta-cell destruction, in a genetically susceptible subject, might be enhanced by several factors including viral infections. In summary, IL-1-beta and TNF-A levels can be used as indicators of continuing autoimmune aggression against beta-cells before the development of extensive beta-cell destruction.
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PMID:Interleukin-1-beta, tumor necrosis factor-alpha, insulin secretion and oral glucose tolerance in non-diabetic siblings of children with IDDM. 1077 98

Engineered insulinoma cell lines may represent an alternative to isolated islets for transplantation therapy of type 1 diabetes. Success of this approach may require development of cell lines that can withstand cytokine-mediated damage. To this end, we have cultured INS-1 insulinoma cells in increasing concentrations of interleukin-1beta (IL-1beta) + gamma-interferon (IFN-gamma), with approximate weekly iterations over an 8-week period. Based on the C,N diphenyl-N'-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium+ ++ bromide (MTT) viability assay, the selected cells, termed INS-1res, were 100% viable after 5 days of treatment with 10 ng/ml of IL-1beta. These cells were also 78 +/- 1.2% viable after 5 days of exposure to the combination of 10 ng/ml IL-1beta and 100 U/ml IFN-gamma, whereas parental INS-1 cells treated in the same manner were only 0.3 +/- 0.03% viable. INS-1res cells were also resistant to treatment with supernatants from activated rat peripheral blood mononuclear cells, whereas only 20% of parental INS-1 cells survived such treatment. The resistance to IL-1beta conferred by this procedure was stable, whereas the partial resistance to IFN-gamma was transient but reinducible by culture in the presence of cytokines. Stable transfection of INS-1res cells with a plasmid containing the human insulin cDNA and expansion of the transfected colonies in the absence of cytokines produced cell lines that were on average more resistant to IL-1beta + IFN-gamma (53 +/- 11%) than similarly transfected clones derived from parental INS-1 cells (15 +/- 7%). Importantly, several INS-1res-derived clones retained the capacity to secrete insulin in response to glucose concentrations over the normal physiological range. With regard to the mechanism by which selection was conferred, we found normal levels of IFN-gamma receptor mRNA, but a 60% reduction in expression of the IL-1 receptor type I (IL-1RI) in INS-1res cells compared with parental INS-1 cells. IL-1beta signaling through p38 MAP kinase was found to be normal in INS-1res cells, suggesting that their expression of IL-1RI is sufficient to maintain cytokine action. However, normal IL-1beta-mediated translocation of NF-kappaB and induction of inducible nitric oxide synthase expression and nitric oxide production was severely impaired in the INS-1res cell lines, suggesting a mechanism for the IL-1beta resistance. In sum, this study defines a strategy for isolation of cytokine-resistant beta-cell lines and provides a new system for studying the mechanisms by which such resistance can be achieved.
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PMID:Selection of insulinoma cell lines with resistance to interleukin-1beta- and gamma-interferon-induced cytotoxicity. 1087 Nov 93


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