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)

The levels of tumor necrosis factor (TNF)-alpha producing cells were analyzed in mice with Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD). Using an ELISPOT assay, we demonstrate an increase in TNF-alpha producing cells in the spinal cords of TMEV-infected SJL/J mice, especially at an active disease stage. The numbers of TNF-alpha producing cells were extremely high in susceptible SJL/J mice compared with the numbers in resistant BALB/c and C57BL/6 mice. TNF-alpha producing cells were also immunohistochemically identified in active lesions of TMEV-IDD at acute as well as chronic stages. The percentage of TNF-alpha producing cells compared with the total number of cells isolated from spinal cords was higher in TMEV-infected SJL/J mice than resistant BALB/c and C57BL/6 mice. Correspondingly, the level of TNF-alpha was much higher in the culture supernatants of both infiltrating cells in the spinal cords and spleen cells from clinically affected animals than that from similarly treated resistant mice. Treatment of virus-infected mice with a mAb specific for TNF-alpha at the beginning of the onset of disease suppressed the development of the demyelinating disease. These findings suggest that TNF-alpha may play an important role in the pathogenicity of TMEV-IDD.
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PMID:The level of tumor necrosis factor-alpha producing cells in the spinal cord correlates with the degree of Theiler's murine encephalomyelitis virus-induced demyelinating disease. 875 45

Insulin-dependent diabetes mellitus (IDDM) is an autoimmune disease that is characterized by selective destruction of insulin-secreting beta-cells. Cytokines have been implicated as effector molecules that participate in both islet inflammation and beta-cell destruction during the development of IDDM. In this study, the effects of cytokines on the expression of inducible nitric oxide synthase (iNOS) and inducible cyclooxygenase (COX-2) by human islets were examined. In combination, the cytokines, human recombinant interleukin-1 beta (IL-1 beta), human recombinant tumor necrosis factor-alpha (TNF-alpha), and human recombinant interferon-gamma (IFN-gamma), induce the time-dependent formation of nitrite and prostaglandin E2 (PGE2) by human islets. The nitric oxide synthase inhibitor NG-monomethyl-L-arginine (L-NMMA) completely inhibits cytokine-induced nitrite formation and attenuates PGE2 production by human islets. L-NMMA does not inhibit cytokine-induced expression of COX-2 by human islets, suggesting that nitric oxide may directly activate cyclooxygenase, an effect that has been previously demonstrated for isolated rat islets. This combination of cytokines (IL-1 beta, TNF-alpha, and IFN-gamma) also induces the expression of iNOS mRNA by human islets as demonstrated by both reverse transcriptase-polymerase chain reaction and Northern blot analysis. We further show that the tyrosine kinase inhibitors genistein and herbimycin A prevent IL-1 beta plus IFN-gamma-induced expression of COX-2 and iNOS and the production of PGE2 and nitric oxide by human islets. These results demonstrate that cytokines induce the expression of iNOS and COX-2 by human islets and that cytokine-induced expression of both COX-2 and iNOS by human islets appears to require the activation of a tyrosine kinase(s).
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PMID:Tyrosine kinase inhibitors prevent cytokine-induced expression of iNOS and COX-2 by human islets. 876 39

Previous studies have shown that anti-gamma-interferon (IFN-gamma) antibody reduces the frequency of autoimmune IDDM in the DP-BB rat. We tested the effects of systemically administered recombinant rat IFN-gamma in both DP-BB and DR-BB rats. Unexpectedly, IFN-gamma markedly reduced the incidence of IDDM as compared with control rats when administered six times per week at a dosage of 280,000 U between ages 30-35 to 105 days or ages 60-64 to 105 days. A lower dosage (28,000 U on alternate days) was also protective when administered to DP-BB rats between birth and age 60 days. However, long-lasting protection against IDDM development over the 1-year study period was achieved only by the highest dosage of IFN-gamma administered from age 30 to 105 days. Ex vivo production of tumor necrosis factor-alpha from splenic lymphoid cells (SLCs) and peritoneal macrophages of the rats treated with IFN-gamma was comparable with that of controls; however, SLCs from the IFN-gamma-treated animals secreted lower amounts of IFN-gamma after stimulation with concanavalin A. IFN-gamma treatment also markedly reduced the frequency of phenotypically activated SLC-expressing class II antigens and interleukin-2 receptor. Finally, in agreement with the observed antidiabetogenic effects, exogenously administered IFN-gamma induced neither insulitis nor IDDM development in DR-BB rats, a subline of DP-BB rats in which autoimmune diabetes rarely occurs spontaneously but can be induced by administration of polyinosinic-polycytidilic acid.
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PMID:Paradoxical antidiabetogenic effect of gamma-interferon in DP-BB rats. 942 71

We examined the role of leukocyte function-associated antigen (LFA)-1 and its counter-receptor intercellular adhesion molecule (ICAM)-1, one of the most important pairs of adhesion molecules, in the development of Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD). Immunohistochemical study showed hyper-expression of ICAM-1 on vascular endothelial cells and expression of LFA-1 on mononuclear infiltrating cells in the spinal cords of TMEV-infected mice. Treatment with mAb to ICAM-1 and/or LFA-1 molecules resulted in significant suppression of the development of demyelinating disease, both clinically and histologically, with down-regulation in the CNS of the respective adhesion molecules after treatment. In mice treated with these mAb, the specific delayed-type hypersensitivity and T cell proliferative responses for TMEV were decreased. The production of tumor necrosis factor-alpha and IFN-gamma in spleen cells was also decreased, but IL-4 production remained unchanged. These data suggest that ICAM-1/LFA-1 interaction is critically involved in the pathogenesis of TMEV-IDD and that antibodies to these adhesion molecules could be a novel therapeutic approach to the treatment of demyelinating diseases such as human multiple sclerosis.
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PMID:Anti-adhesion molecule therapy in Theiler's murine encephalomyelitis virus-induced demyelinating disease. 946 11

Non-obese diabetic (NOD) mice spontaneously develop insulin-dependent (type 1) diabetes mellitus (IDDM) caused by T cells which destroy the insulin-producing islet beta-cells. Since cytokines are involved in this auto-immune beta-cell damage, we used an ELISPOT assay to enumerate the islet-associated T cells that secreted interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) or interleukin-4 (IL-4). We used mitogenic anti-CD3 antibody to activate all the T cells capable of responding, irrespective of their antigen specificity. We found that NOD females, more susceptible than males to IDDM, accumulated islet IFN-gamma producers more rapidly with age than did the males. Acceleration of male IDDM by cyclophosphamide led to a marked increase in IFN-gamma secreting islet T cells. In contrast, a decrease in IFN-gamma-producing islet T cells was associated with arrest of IDDM by administration of peptide p277 of the 60 kDa heat-shock protein (hsp60) to 12-week-old female NOD mice. The p277-treated mice later manifested a greater number of islets and fewer leukocytes per islet than did the mice treated with a bacterial hsp60 peptide. Thus, the development of diabetes could be correlated with the accumulation in the islets of T cells producing IFN-gamma, and destructive insulitis could be downregulated by the administration of a single peptide.
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PMID:Islet T cells secreting IFN-gamma in NOD mouse diabetes: arrest by p277 peptide treatment. 948 Jul 25

Pentoxifylline (PTX) has been recently shown to have a variety of immunomodulatory effects. PTX suppresses the production of tumor necrosis factor-alpha (TNF-alpha) and T helper type 1 (Th1) cytokine, interferon-gamma (IFN-gamma), whereas it increases the production of Th2 cytokines, such as interleukin-4 (IL-4) and IL-10. In the pathogenesis of Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease (TMEV-IDD), encephalitogenic Th1 cells may play a major role. We examined the effect of PTX treatment on TMEV-IDD. We treated SJL/J mice, inoculated TMEV intracerebrally, with either PTX or saline from days -2 to 12 and days 14 to 27 postintracerebral infection. In the group of mice treated with PTX from days -2 to 12, the onset of TMEV-IDD was suppressed. On the other hand, in the group of mice treated with PTX from days 14 to 27 or saline, the onset of TMEV-IDD was not inhibited. The results of enzyme-linked immunospot (ELISPOT) assay of spleen cells of mice showed that the production of TNF-alpha and IFN-gamma was significantly inhibited (TNF-alpha and IFN-gamma, p < 0.001) and IL-4 and IL-10 production was significantly increased (IL-4, P < 0.001; and IL-10, P < 0.05, respectively) in the group of mice treated with PTX from days -2 to 12. These findings suggest that PTX suppresses the onset of TMEV-IDD by suppressing the production of TNF-alpha and modulating Th1-dominant immune responses into Th2-dominant ones.
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PMID:The effect of pentoxifylline (PTX) on Theiler's murine encephalomyelitis (TMEV)-induced demyelinating disease. 966 56

A mechanism of autoimmune destruction of islet beta-cells in type 1 diabetes has been proposed to be the binding of Fas ligand (FasL) on T-cells to Fas receptors on beta-cells. We investigated this proposal by examining the expression of FasL and Fas on islet-infiltrating T-cells and beta-cells in relation to beta-cell destruction in a syngeneic islet transplant model in NOD mice. Diabetic NOD mice were transplanted with syngeneic islets and injected with complete Freund's adjuvant, which prevented diabetes recurrence (nondestructive insulitis), and with phosphate-buffered saline, which did not (beta-cell destructive insulitis). Two-color immunohistochemical assays revealed that FasL was expressed on CD4+ T-cells, CD8+ T-cells, and beta-cells in islet grafts from both diabetic and normoglycemic mice, and the percentage of each type of cell that expressed FasL was greater in islet grafts from normoglycemic compared with diabetic mice. In contrast, Fas was expressed on CD4+ T-cells, CD8+ T-cells, and beta-cells in islet grafts from diabetic mice, but it was nearly or totally absent on these cells in islet grafts from normoglycemic mice. Similarly, polymerase chain reaction analysis of islet grafts revealed that Fas mRNA expression was significantly lower in islet grafts from normoglycemic compared with diabetic mice. Also, mRNA levels of interleukin (IL)-1alpha, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma were significantly lower in islet grafts from normoglycemic mice. Finally, Fas was induced on NOD islet cells by incubation with IL-1beta, IFN-gamma, and the combination of IL-1beta, TNF-alpha, and IFN-gamma. These findings support the concept that cytokine-induced Fas receptor expression on islet beta-cells is a mechanism for their destruction by FasL-expressing CD4+ and CD8+ T-cells and, possibly, by FasL-expressing beta-cells themselves.
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PMID:Beta-cell destruction in NOD mice correlates with Fas (CD95) expression on beta-cells and proinflammatory cytokine expression in islets. 989 18

Apoptosis has been identified as a mechanism of pancreatic islet beta-cell death in autoimmune diabetes. Proinflammatory cytokines are candidate mediators of beta-cell death in autoimmune diabetes, and these cytokines can induce beta-cell death by apoptosis. In the present study, we examined whether transfection of human islet beta-cells with an anti-apoptotic gene, bcl-2, can prevent cytokine-induced beta-cell destruction. Human islet beta-cells were transfected by a replication-defective herpes simplex virus (HSV) amplicon vector that expressed the bcl-2 gene (HSVbcl-2) and, as a control, the same HSV vector that expressed a beta-galactosidase reporter gene (HSVlac). Two-color immunohistochemical staining revealed that 95+/-3% of beta-cells transfected with HSVbcl-2 expressed Bcl-2 protein compared with 14+/-3% of beta-cells transfected with HSVlac and 19+/-4% of nontransfected beta-cells. The bcl-2-transfected beta-cells were fully protected from impaired insulin secretion and destruction resulting from incubation for 5 days with the cytokine combination of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma. In addition, the bcl-2-transfected islet cells were significantly protected from cytokine-induced lipid peroxidation and DNA fragmentation. These results demonstrate that cytokine-induced beta-cell dysfunction and death involve mechanisms subject to regulation by an anti-apoptotic protein, Bcl-2. Therefore, bcl-2 gene therapy has the potential to protect human beta-cells in pancreatic islets, or islet grafts, from immune-mediated damage in type 1 diabetes.
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PMID:Transfection of human pancreatic islets with an anti-apoptotic gene (bcl-2) protects beta-cells from cytokine-induced destruction. 1034 8

Interleukin (IL)-13 is a cytokine primarily produced by the T-helper (Th)-2 subset of lymphocytes that possesses powerful anti-inflammatory properties. Here, we have evaluated the impact of IL-13 treatment on development of type 1 diabetes in diabetes-prone nonobese diabetic (NOD) mice. Prolonged treatment with recombinant human IL-13 (hIL-13) markedly diminished the incidence of spontaneous type 1 diabetes in the mice. Female NOD mice treated from age 5-16 weeks with hIL-13 also showed significantly milder insulitis than control mice. The preventive action of hIL-13 was associated with a slight but significant change from a type 1 to a type 2 cytokine response. Accordingly, splenic lymphoid cells (SLC) from hIL-13-treated mice secreted less interferon (IFN)-gamma upon ex vivo stimulation with Concanavalin A than controls, and anti-CD3 monoclonal antibody-induced activation of T-cells in vivo resulted in lower blood levels of IFN-gamma and tumor necrosis factor-alpha and augmented blood levels of IL-4 in NOD mice pretreated with hIL-13. hIL-13 treatment also increased the blood levels of IgE and inhibited the transfer of type 1 diabetes by spleen cells from a diabetic donor to irradiated recipients. Taken together, these data add hIL-13 to the list of cytokines capable of downregulating immunoinflammatory diabetogenic pathways in NOD mice, and further support the concept that IL-4-related anti-inflammatory cytokines might have a role in the prevention of type 1 diabetes.
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PMID:Interleukin-13 prevents autoimmune diabetes in NOD mice. 1042 68

Type 1 diabetes is a disease characterized by progressive loss of beta-cell function due to an autoimmune reaction affecting the islets of Langerhans. It is now generally accepted that cytokines are implicated in the pathogenesis of autoimmune diseases. Animal studies have shown that interleukin-1beta, tumor necrosis factor-alpha, and interferon-gamma affect type 1 diabetes development profoundly. It has been suggested that beta-cells are destroyed by cytokine-induced free radical formation before cytotoxic T-helper (Th)-lymphocytes and/or autoantibody-mediated cytolysis. This hypothesis is known as the "Copenhagen model." We introduce a mathematical model encompassing the various processes within this framework. The model is expressed in rate equations describing the changes in numbers of beta-cells, macrophages, and Th-lymphocytes. Being concerned with the earliest events, we explore the conditions necessary to maintain self-sustained beta-cell elimination based on the feedback between immune cells and insulin-producing cells. The motivation for this type of analysis becomes clear when we consider the multifactorial and complicated nature of the disease. Indeed, recent research has provided detailed information about the different factors that contribute to the development of the disease, stressing the importance of incorporating these findings into a more general picture. A mathematical formalism allows for a more comprehensive description of the biological problem and can reveal nonintuitive properties of the dynamics. Despite the rather complicated structure of the equations, our main conclusion is simple: onset of type 1 diabetes is due to a collective, dynamical instability, rather than being caused by a single etiological factor.
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PMID:Onset of type 1 diabetes: a dynamical instability. 1048 May 94


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