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)

Proinflammatory cytokines are believed to be important in pancreatic beta-cell destruction in the development of type 1 diabetes. They act by upregulation of genes including Fas and inducible nitric oxide synthase (iNOS), which have both been shown to lead to beta-cell death in vitro. We used mice deficient in the interleukin (IL)-1 receptor (IL-1R) to assess the contribution of IL-1 to different models of diabetes. IL-1R-deficient islets were protected from the damaging effects of tumor necrosis factor (TNF) and interferon (IFN)-gamma in vitro, and beta-cell expression of iNOS was reduced, suggesting that IL-1 mediates the induction of iNOS by TNF and IFN-gamma. IL-1 action was not required for induction of class I major histocompatibility complex or Fas by TNF and IFN-gamma. IL-1R-deficient nonobese diabetic (NOD) mice developed diabetes significantly slower than wild-type mice. IL-1R deficiency did not affect diabetes in 8.3 TCR transgenic NOD mice but prolonged the time to diabetes in BDC2.5 TCR transgenic NOD mice. We conclude that IL-1R deficiency slows progression to diabetes in NOD mice but on its own does not prevent diabetes.
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PMID:IL-1 receptor deficiency slows progression to diabetes in the NOD mouse. 1469 5

The specific contributions of islet cell microenvironment during the development of autoimmune type 1 diabetes remain unclear. The aims of this study were to identify early immune-driven abnormalities in islets and pancreatic lymph nodes of NOD mice by cDNA arrays. We compared gene expression profiles of purified islets and pancreatic lymph nodes of 4-week-old NOD mice to NOD-SCID and BALB/c mice. To further characterize the networks implicated in beta-cell destruction, we also performed a time-course analysis using islets and pancreatic lymph nodes of NOD mice from 2 to 25 weeks of age. We found consistent changes by cDNA arrays and RT-PCR analyses among islet genes before the detection of CD3+ T cells in the islet periphery associated with dendritic cell attraction, lymphocyte homing, and apoptosis. In contrast to IL-1, TYNFSF13B and osteopontin genes which were specifically activated, the immunoregulatory cytokine IL-11 was poorly detected in NOD islets and pancreatic lymph nodes. Genes involved in angiogenesis were also specifically activated in NOD islets of 2 and 4 weeks of age. The present time-course macroarray and RT-PCR analyses provides a detailed picture of the different genes involved in autoimmune diabetes and illustrates the importance of islet cell microenvironment that prepares the late beta-cell destruction.
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PMID:Early events in islets and pancreatic lymph nodes in autoimmune diabetes. 1523 50

While it is generally agreed that apoptosis of pancreatic beta-cells is the most important and final step in the progression of type 1 diabetes without which clinical diabetes does not develop, it has not been elucidated which molecule(s) are the real culprit(s) in type 1 diabetes. Perforin, FasL, TNFalpha, IL-1, IFNgamma, and NO have been claimed as the effector molecules; however, they, as a single agent, might explain only part of beta-cell death in type 1 diabetes. While FasL was initially considered as a strong candidate for the most important death effector, following experiments cast doubt on such a hypothesis. Combinations or synergism between IFNgamma and TNFalpha or IL-1beta are being revisited as the death effectors, and molecular mechanism explaining such a synergism was addressed in several recent papers. The role of NF-kappaB for pancreatic beta-cell death in type 1 diabetes is also controversial. While NF-kappaB plays anti-apoptotic roles in most other death models, its role in type 1 diabetes might be different probably due to the involvement of multiple cytokines at different stages of the disease progression and the peculiarity of pancreatic beta-cells. Recent papers also suggested a role for Ca2+ in cytokine-mediated pancreatic beta-cell death. Such participation of Ca2+ in beta-cell death appears to have a close relevance to the mitochondrial events or ER stress that constitutes an important part of cell death machinery recently identified.
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PMID:Death effectors of beta-cell apoptosis in type 1 diabetes. 1546 23

The hallmark of immune-mediated type 1 diabetes is T cell-mediated destruction of the insulin-producing beta cells in the islets, which results from an imbalance between disease promoting factors and protective elements. The precise mechanisms of beta cell destruction leading to diabetes remain unclear. There are many molecules, including Fas ligand (FasL) and cytokines, such as IL-1, TNF-alpha and IFN-gamma that cause release of other cytokine-mediators that have potential to damage the beta cells. The beta cell-death appears to ultimately be caused by receptor (Fas/FasL)-mediated mechanisms and/or by secretion of cytotoxic molecules (e.g., granzymes, perforin). FasL-mediated beta cell damage might play a role in promoting insulitis and beta cell destruction in autoimmune diabetes in addition to toxic molecules, such as reactive oxygen species (superoxide, hydroxy radical, nitric oxide) or perforin. Furthermore, DNA damage in beta cells leads to poly (ADP-ribose) polymerase-activation which will increase NAD consumption and rapid depletion of NAD compromise ATP production in the cells. Nicotinamide inhibits poly (ADP-ribose) polymerase and reduces nitric oxide accumulation in the NOD pancreas and protect beta cells against radical-induced necrosis. Transgenic mice with beta cell specific overexpression of copper, zinc superoxide dismutase, or thioredoxin are resistant to autoimmune and STZ-induced diabetes. It is apparent that a number of different mechanisms of beta cell destruction are operative in type 1 diabetes. Blockage of multiple pathways, rather than a single pathway, of beta cell-death may, therefore be necessary to fully protect beta cells from destruction and thereby prevent type 1 diabetes.
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PMID:Prevention of type 1 diabetes: from the view point of beta cell damage. 1556 75

Cytokines are involved in the pathogenesis of type 1 diabetes. The disease is characterized by T cell-mediated beta cell destruction and a biased Th1 cytokine pattern. Type 2 diabetes also presents an inflammatory cytokine imbalance. In this study, mRNA expression of cytokines IL-12, TNF-alpha, IL-1, and IL-6 was studied in monocytes from diabetic patients after in vitro immune stimulation. Whereas IL-12(p40) was highly expressed in type 1 diabetic patients, TNF-alpha, IL-1, and IL-6 transcripts were elevated in type 1 but especially type 2 diabetic patients compared with healthy controls, suggesting an important proinflammatory milieu. We conclude that circulating monocytes from type 1 as well as type 2 diabetic patients have an aberrant cytokine profile when stimulated by an immune stimulus such as IFNgamma. This condition not only is likely to be involved in disease pathogenesis, but may contribute to its later complications.
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PMID:Monocytic expression behavior of cytokines in diabetic patients upon inflammatory stimulation. 1569 96

IL-18 is a type 1 pro-inflammatory cytokine with structural similarities to IL-1 and in synergy with IL-12 stimulates IFN-gamma production from T lymphocytes and polarizes development and function of Th1 cells. Because IL-1, IFN-gamma, and up-regulated Th1-mediated events are involved in the pathogenesis of both human and rodent type 1 diabetes mellitus, we have evaluated the effects of a specific inhibitor of IL-18 (the IL-18bp:FcIg) on the development of accelerated forms of autoimmune diabetes in NOD mice. The data show that prolonged prophylactic treatment with IL-18bp:FcIg significantly reduced the cumulative incidence of diabetes induced in NOD mice either by adoptive transfer of diabetogenic cells or by injection with large doses of cyclophosphamide. These data provide the first in vivo evidence for the diabetogenic role of IL-18 in immuno-inflammatory diabetogenic pathways in NOD mice.
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PMID:IL-18 binding protein fusion construct delays the development of diabetes in adoptive transfer and cyclophosphamide-induced diabetes in NOD mouse. 1587 24

Different degrees of beta-cell failure and apoptosis are present in type 1 and type 2 diabetes. It has been recently suggested that high glucose-induced beta-cell apoptosis in type 2 diabetes shares a final common pathway with type 1 diabetes, involving interleukin-1beta (IL-1beta) production by beta-cells, nuclear factor-kappaB (NF-kappaB) activation, and death via Fas-FasL. The aim of this study was to test whether human islet exposure to high glucose in vitro, or to the type 2 diabetes environment in vivo, induces IL-1beta expression and consequent activation of NF-kappaB-dependent genes. Human islets were isolated from five normoglycemic organ donors. The islets were cultured for 48 h to 7 days at 5.6, 11, or 28 mmol/l glucose. For comparative purposes, islets were also exposed to IL-1beta. Gene mRNA expression levels were assessed by real-time RT-PCR in a blinded fashion. Culture of the human islets at 11 and 28 mmol/l glucose induced a four- to fivefold increase in medium insulin as compared with 5.6 mmol/l glucose, but neither IL-1beta nor IL-1 receptor antagonist (IL-1ra) expression changed. IL-1beta and IL-1ra protein release to the medium was also unchanged. Stimulated human monocytes, studied in parallel, released >50-fold more IL-1beta than the islets. There was also no glucose-induced islet Fas expression. Expression of the NF-kappaB-dependent genes IkappaB-alpha and monocyte chemoattractant protein (MCP)-1 was induced in human islets by IL-1beta but not by high glucose. In a second set of experiments, human islets were isolated from seven type 2 diabetic patients and eight control subjects. The findings on mRNA levels were essentially the same as in the in vitro experiments, namely the in vivo diabetic state did not induce IL-1beta, Fas, or MCP-1 expression in human islets, and also did not modify IL-1ra expression. The present findings suggest that high glucose in vitro, or the diabetic milieu in vivo, does not induce IL-1beta production or NF-kappaB activation in human islets. This makes it unlikely that locally produced IL-1beta is an important mediator of glucotoxicity to human islets and argues against the IL-1beta-NF-kappaB-Fas pathway as a common mediator for beta-cell death in type 1 and type 2 diabetes.
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PMID:Is there a role for locally produced interleukin-1 in the deleterious effects of high glucose or the type 2 diabetes milieu to human pancreatic islets? 1624 50

Vitamin D and interleukin (IL)-1 have been suggested to function in the pathogenesis of type 1 diabetes mellitus (T1DM). Therefore, we examined the influence of gene polymorphisms in vitamin D receptor (VDR) and interleukin-1 receptor type I (IL-1-R1) on susceptibility to T1DM in the Dalmatian population of South Croatia. We genotyped 134 children with T1DM and 132 controls; for FokI polymorphism studies, we extended the control group to an additional 102 patients. The VDR gene polymorphism FokI displayed unequal distribution (P = 0.0049) between T1DM and control groups, with the ff genotype occurring more frequently in T1DM individuals whereas the VDR gene polymorphism Tru9I did not differ in frequency between studied groups. All tested polymorphisms of the IL-1-R1 gene [PstI, HinfI, and AluI (promoter region) and PstI-e (exon 1B region)] displayed no differences between cases and controls. Haplotype analysis of the VDR gene (FokI, BsmI, ApaI, TaqI, Tru9I) and of the IL-1-R1 gene (PstI, HinfI, AluI, PstI-e) found haplotypes VDR FbATu (P = 0.0388) and IL-1-R1 phap' (P = 0.0419) to be more frequent in T1DM patients whereas the BatU haplotype occurred more often in controls (P = 0.0064). Our findings indicate that the VDR FokI polymorphism and several VDR and IL-1-R1 haplotypes are associated with susceptibility to T1DM in the Dalmatian population.
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PMID:FokI polymorphism, vitamin D receptor, and interleukin-1 receptor haplotypes are associated with type 1 diabetes in the Dalmatian population. 1625 58

Cytokines, particularly interleukin (IL)-1beta, have been postulated to cause beta-cell destruction in type 1 diabetes. We tested the efficacy of an IL-1 cytokine trap in counteraction of suppressive and toxic effects after exposure of rat pancreatic islets in vitro to IL-1beta. The IL-1 cytokine trap used herein comprised extracellular domains of the IL-1 receptor accessory protein and the human IL-1 receptor 1 arranged inline and fused to the Fc portion of human IgG1. Groups of isolated rat pancreatic islets were maintained in medium culture with or without IL-1beta (150 pmol/l) for 48 hours in the absence or presence of the IL-1 trap at 1-, 10-, or 100-fold excess the molar concentration of the cytokine. IL-1beta alone induced a strong inhibition of insulin secretion and glucose oxidation rate and a marked increase in medium nitrite accumulation as an indicator of nitric oxide generation. When the IL-1 trap was used at a ratio 10:1 or 100:1, a complete protection against these effects were observed. Moreover, the IL-1 trap (100:1) blocked the increased islet cell death seen in islets treated with a combination of IL-1beta + tumor necrosis factor-alpha + interferon-gamma as well as functional suppression induced by the cytokine combination. In conclusion, we show that addition of an IL-1 trap can protect rat pancreatic islets in vitro against noxious effects induced by IL-1beta. Exploring the IL-1 trap in relevant animal models of type 1 diabetes represents an interesting future intervention strategy.
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PMID:Complete protection against interleukin-1beta-induced functional suppression and cytokine-mediated cytotoxicity in rat pancreatic islets in vitro using an interleukin-1 cytokine trap. 1664 98

CD8(+) cytotoxic T lymphocytes (CTL) can rapidly kill beta-cells and therefore contribute to the development of type 1 diabetes (T1D). CTL-mediated beta-cell killing can occur via perforin-mediated lysis, Fas-Fas-L interaction, and the secretion of TNF-alpha or IFN-gamma. The secretion of IFN-gamma can contribute to beta-cell death directly by eliciting nitric oxide production, and indirectly by upregulating MHC class I and 'unmasking' beta-cells for recognition by CTL. Earlier studies in the RIP-LCMV mouse model of diabetes showed that disruption of beta-cell IFN-gamma signaling alone abolished the direct detrimental effects of IFN-gamma, but not MHC class I upregulation. Suppressor of cytokine signaling-1 (SOCS-1) represses several crucial cytokine signaling pathways simultaneously, among them IFN-gamma and IL-1-beta. We therefore evaluated the protective capacity of islet cell SOCS-1 expression in the CD8(+) mediated RIP-LCMV diabetes model. Clinical disease was prevented in over 90% of the mice. Not only absence of MHC-I and Fas upregulation, but also resistance to cytokine-induced killing of beta-cells and a complete lack of CXCL-10 (IP10) production in islets led to a lack of islet infiltration and impaired activation of autoaggressive CD4(+) and CD8(+) T-cells in these mice. Thus, SOCS expression renders beta-cells resistant to CTL attack in a mouse model of T1D.
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PMID:SOCS-1 protects from virally-induced CD8 T cell mediated type 1 diabetes. 1704 60


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