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)

We investigated the expression of Th1- and Th2-associated chemokine receptors on peripheral blood lymphocytes at diagnosis and in the first phase of type 1 diabetes. Peripheral blood mononuclear cells (PBMCs) of 25 patients with newly diagnosed type 1 diabetes, 10 patients with longstanding type 1 diabetes, and 35 healthy control subjects were examined for expression of the chemokine receptors CXCR4 (naive T-cells), CCR5 and CXCR3 (Th1 associated), and CCR3 and CCR4 (Th2 associated) on CD3+ lymphocytes. Furthermore, we analyzed chemokine serum levels (monocyte chemoattractant protein [MCP]-1, macrophage inflammatory protein [MIP]-1alpha, MIP-1beta, and RANTES [regulated on activation, normal T-cell expressed and secreted]) and phytohemagglutinin (PHA)-stimulated cytokine secretion of Th1- (gamma-interferon [IFN-gamma] and tumor necrosis factor-alpha [TNF-alpha]) and Th2 (interleukin [IL]-4 and -10)-associated cytokines by PBMC. The patients with newly diagnosed type 1 diabetes were followed for these parameters at 6-12 months after diagnosis. The PBMCs of patients with newly diagnosed but not with longstanding type 1 diabetes showed reduced expression of the Th1-associated chemokine receptors CCR5 (P < 0.001 vs. control subjects) and CXCR3 (P < 0.002 vs. control subjects). This reduction correlated with reduced IFN-gamma and TNF-alpha production of PBMCs after PHA stimulation and reversed 6-12 months after diagnosis to normal levels. CCR4 cells were reduced in both newly diagnosed and longstanding type 1 diabetic patients, which correlated to reduced PHA-stimulated IL-4 production. MIP-1alpha and MIP-1beta levels were considerably elevated in a subgroup of patients with newly diagnosed diabetes. We assume that Th1-associated peripheral T-cells are reduced in a narrow time window at the time of diagnosis of diabetes, possibly due to extravasation in the inflamed pancreas. Thus, chemokine receptor expression of peripheral blood lymphocytes may be a useful surrogate marker for the immune activity of type 1 diabetes (e.g., in intervention trials).
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PMID:Reduced expression of Th1-associated chemokine receptors on peripheral blood lymphocytes at diagnosis of type 1 diabetes. 1214 60

The mechanism by which tumor necrosis factor-alpha (TNF) differentially modulates type I diabetes mellitus in the nonobese diabetic (NOD) mouse is not well understood. CD4+CD25+ T cells have been implicated as mediators of self-tolerance. We show (i) NOD mice have a relative deficiency of CD4+CD25+ T cells in thymus and spleen; (ii) administration of TNF or anti-TNF to NOD mice can modulate levels of this population consistent with their observed differential age-dependent effects on diabetes in the NOD mouse; (iii) CD4+CD25+ T cells from NOD mice treated neonatally with TNF show compromised effector function in a transfer system, whereas those treated neonatally with anti-TNF show no alteration in ability to prevent diabetes; and (iv) repeated injection of CD4+CD25+ T cells into neonatal NOD mice delays diabetes onset for as long as supplementation occurred. These data suggest that alterations in the number and function of CD4+CD25+ T cells may be one mechanism by which TNF and anti-TNF modulate type I diabetes mellitus in NOD mice.
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PMID:Tumor necrosis factor-alpha regulation of CD4+CD25+ T cell levels in NOD mice. 1222 Dec 81

The major predisposing genetic component in type 1 diabetes maps to the major histocompatibility complex locus in both mice and humans. To verify the HLA class II association with disease pathogenesis, we adopted the transgenic approach. Expression of HLA-DQ8, the molecule showing the strongest association with human type 1 diabetes, in the diabetes-predisposing milieu of NOD mice in the absence of the endogenous class II molecule I-A(g7) did not render susceptibility to type 1 diabetes. To study if providing a local proinflammatory environment would lead to diabetes in these mice, Abeta(o).NOD.DQ8 were bred with C57BL/6 mice expressing tumor necrosis factor (TNF)-alpha in the beta-cells of the islets of Langerhans. Surprisingly, although diabetes was evident in the F1 intercross expressing rat insulin promoter (RIP)-TNF, offspring lacking either endogenous or transgenic class II molecules developed accelerated diabetes with high frequency in both sexes. Moreover, expression of any functional class II molecule seemed to confer significant protection from diabetes in this model. Thus, neonatal expression of TNF-alpha in an islet-specific manner bypassed the requirement of CD4(+) T-cells and resulted in diabetes that could be mediated by CD8(+) T-cells. We also show for the first time that diabetes in NOD.RIP-TNF mice can occur independent of inheritance of NOD-derived idd1.
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PMID:Accelerated diabetes in rat insulin promoter-tumor necrosis factor-alpha transgenic nonobese diabetic mice lacking major histocompatibility class II molecules. 1254 Jun 6

Idiopathic dilated cardiomyopathy (IDC) is one of the major causes of death in humans and has been linked to Coxsackievirus B (CVB) infection. The aim of this study was to analyze phenotypes of heart-infiltrating immune cells in patients suffering from myocarditis and IDC associated with CVB infections. We found that the myocardium of these patients was infiltrated by CD4(+) and CD8(+) T lymphocytes as well as macrophages. Evidence of CVB3/4 infections was also found. In the majority of patients, the T-cell receptor repertoire (TCR) of the infiltrating lymphocytes was restricted, with a polyclonal expansion of the Vbeta7 gene family. We also found that human leukocyte antigen (HLA) class II alleles associated with susceptibility to type 1 diabetes (HLA-DR4 and HLA-DQA1*04/05/06 alleles) were remarkably infrequent in IDC patients (p < 0.005), thus suggesting that they might confer protection against IDC. Finally, mRNA for interleukin-1beta, interferon-gamma, and tumor necrosis factor-alpha was detected in the cardiac specimens, although at a lower level compared with specimens from hearts without signs of viral infections. We conclude that CVB infection of the human myocardium is associated with a selective, yet polyclonal activation of different T-cell subsets in genetically susceptible individuals. This immune response may play a critical role in modulating disease progression after viral infections.
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PMID:Expansion of specific alphabeta+ T-cell subsets in the myocardium of patients with myocarditis and idiopathic dilated cardiomyopathy associated with Coxsackievirus B infection. 1255 22

The human leukocyte antigen (HLA) class III region, located on chromosome 6p21, has been regarded as one of the susceptible loci for type 1 diabetes. Because it contains many genes related to inflammatory and immune responses, including tumor necrosis factor (TNF), lymphotoxin-alpha (LT-alpha), and allograft inflammatory factor 1 (AIF-1) genes, it is unclear which gene within the class III region is responsible for the susceptibility to the disease. We sequenced the AIF-1 gene region and detected three novel polymorphisms, all of which were diallelic and localized at introns. Then, we investigated AIF-1, TNF, and LT-alpha gene polymorphisms in 165 patients with type 1 diabetes, consisting of 90 patients with young-onset type 1 diabetes, 75 patients with adult-onset type 1 diabetes, and 200 control patients. We also analyzed TNF receptors type 1 (TNFR1) and type 2 (TNFR2) gene polymorphisms, located on chromosome 12p13 and 1p36, respectively. Although there were significant differences between type 1 diabetes patients and controls in the distributions of TNF promoter polymorphisms at position -1031 and -857, and LT-alpha gene NcoI polymorphism, none of them was independently associated with the disease after two-locus analysis with HLA class II alleles. We detected the significantly increased frequency of the -383C allele, located in the TNFR-1 promoter region, in both young-onset and adult-onset diabetes patients compared with controls. In addition, the -383C allele was found to be associated with higher expression of the TNFR1 gene than that of -383A allele in in vitro expression. These results suggest that the TNFR1 gene region might be a susceptible locus to type 1 diabetes in Japanese.
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PMID:TNF, TNF receptor type 1, and allograft inflammatory factor-1 gene polymorphisms in Japanese patients with type 1 diabetes. 1255 34

Periodontal disease is the result of a complex interplay of bacterial infection and host responses, and is often modified by various systemic diseases such as diabetes mellitus. Such diseases are capable of affecting the periodontium and/or the treatment of periodontal disease. However, recent research has changed our concept of how periodontal disease should be treated. Here we present several concerns directed towards the periodontal therapy of patients with diabetes mellitus based on our studies. When treating periodontitis patients who have diabetes mellitus it is important to consider the type of diabetes. Patients with non-insulin dependent diabetes mellitus can be further classified according to the degree of insulin resistance, since recent epidemiological studies have suggested that successful anti-microbial therapy might result in improved insulin resistance in highly insulin resistant patients. Because the major contributing factor for insulin resistance is currently considered to be the proinflammatory cytokine tumor necrosis factor-alpha (TNF-alpha), and because periodontal surgery may cause transient bacteremia which may up-regulate the serum TNF-alpha level, which in turn suppresses insulin action, patients should be strictly treated non-surgically and their serum TNF-alpha levels should be periodically monitored. On the other hand, diabetic patients positive for serum anti-glutamate decarboxylase auto-antibody should be examined for the source of this antibody, since 1) gingival and periodontal ligament fibroblasts were found to express glutamate decarboxylase, and 2) some otherwise healthy periodontitis patients develop anti-glutamate decarboxylase antibody. Thus, chronic periodontitis may influence the level of this antibody which is widely used as a predictive marker for slowly progressive insulin dependent diabetes mellitus. Not only is periodontal disease thereby affected by systemic diseases, but carefully managed periodontal therapy may also have a positive effect on the general health of patients with systemic diseases.
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PMID:Negative effects of chronic inflammatory periodontal disease on diabetes mellitus. 1266 61

Genes in the early region 3 (E3) of the adenovirus genome allow the virus to evade host immune responses by interfering with major histocompatibility (MHC) class I-mediated antigen presentation and tumor necrosis factor-alpha (TNF-alpha)- or Fas-induced apoptosis of infected cells. Autoimmune type 1 diabetes (T1D) is inhibited in NOD mice transgenically expressing all E3 genes under control of a rat insulin promoter (RIPE3/NOD). For dissecting the protective mechanisms afforded by various E3 genes, they were subdivided into RIP-driven transgene constructs. Strong T1D protection mediated at the beta-cell level characterized DL704/NOD mice lacking the E3 gp19K gene suppressing MHC class I expression but retaining the 10.4K, 14.5K, and 14.7K genes inhibiting Fas- or TNF-alpha-induced apoptosis and TNF-alpha-induced NF-kB activation. Much weaker protection characterized DL309/NOD mice expressing the gp19K but not the 10.4K, 14.5K, and 14.7K genes. While RIPE3/NOD splenocytes had an unexpected decrease in ability to adoptively transfer T1D, splenocytes from both the DL704 and DL309 stocks efficiently did so. These findings indicate that all E3 genes must be expressed to inhibit the diabetogenic potential of NOD immune cells. They also demonstrate that the antiapoptotic E3 genes most effectively protect pancreatic beta-cells from diabetogenic immune responses.
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PMID:Adenovirus early region 3 antiapoptotic 10.4K, 14.5K, and 14.7K genes decrease the incidence of autoimmune diabetes in NOD mice. 1271 41

Recent studies incriminating tumor necrosis factor (TNF)-alpha as the final effector in pancreatic beta-cell death in type 1 diabetes underscore the potential role of TNF-alpha-dependent NF-kappaB activation as an important modulator of pancreatic beta-cell death in autoimmune diabetes. Although nuclear factor (NF)-kappaB activation has been implicated in the protection of target cells against apoptosis by a variety of death effectors, its role in pancreatic islet cell death is not clear. We studied the role of NF-kappaB activation in pancreatic islet cell death by using a gamma-interferon (IFN-gamma)/TNF-alpha synergism model we had previously reported. TNF-alpha induced inhibitor of kappaB (IkappaB) degradation and p65 translocation from cytoplasm to nuclei in MIN6N8 insulinoma cells. The NF-kappaB DNA-binding nuclear complex activated by TNF-alpha contained both the p65 and p50 subunit. IFN-gamma pretreatment did not affect TNF-alpha-induced NF-kappaB activation. Treatment with a proteasome inhibitor blocked p65 translocation and induced susceptibility to TNF-alpha in otherwise resistant insulinoma cells or primary pancreatic islet cells. Specific inhibition of NF-kappaB activation by adenoviral transduction of IkappaB "superrepressor" also sensitized insulinoma cells and primary islet beta-cells to TNF-alpha-induced apoptosis. These results suggest the protective role of NF-kappaB activation against cytokine-mediated pancreatic beta-cell death, contrary to previous reports implicating NF-kappaB as a mediator of pancreatic islet cell death.
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PMID:Nuclear factor kappaB protects pancreatic beta-cells from tumor necrosis factor-alpha-mediated apoptosis. 1271 48

Free radical formation evoked by proinflammatory cytokines has been suggested to be involved in the destruction of beta-cells in the course of type 1 diabetes development. However, there is no direct evidence to support this hypothesis. In this study, we used electron paramagnetic resonance spectroscopy in conjunction with spin-trapping methodology to directly determine whether cytokines give rise to free radical formation in the islets. Our results demonstrate that direct, in vivo administration of tumor necrosis factor-alpha (1,000 units), interleukin-1beta (1,000 units), and interferon-gamma (2,000 units) into the rat pancreas through a bile duct cannula leads to the formation of lipid-derived free radicals in this tissue. These free radicals most likely are generated by the beta-cells because previous depletion of these cells by streptozotocin abolished the cytokine-induced free radical formation. Furthermore, macrophage depletion was found to decrease the production of free radicals. Inhibition of the enzyme inducible cyclooxygenase (COX-2) and the transcription factor nuclear factor-kappaB (NF-kappaB) significantly diminished the free radicals' signal intensity, implicating these factors in the formation of free radicals. We have also demonstrated that cytokine treatment leads to the activation of NF-kappaB in the pancreatic islets of the rats.
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PMID:Free radicals and the pathogenesis of type 1 diabetes: beta-cell cytokine-mediated free radical generation via cyclooxygenase-2. 1288 15

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


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