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 measured net uptake and release of amino acids in the brain of 7 nondiabetic and six diabetic subjects. Duration of insulin-dependent diabetes (IDDM) was 19.4 +/- 2.1 years. Arteriojugular vein measurements were performed before and after 120 minutes of insulin infusion and ensuing Biostator-regulated normoglycemia. Cerebral blood flow was measured during normoglycemia by 11-CH3-F and positron emission tomography. During hyperglycemia in the IDDM subjects, arterial concentrations of valine and leucine were higher, and those of glutamic acid and arginine lower, than in nondiabetic subjects. Insulin infusion lowered levels of most amino acids in both groups. Insulin treatment did not significantly affect the uptake or release of amino acids. Significant net uptake of branched-chain amino acids was noted in both groups, as well as uptake of lysine and phenylalanine in the IDDM subjects. The sum of measured differences was not different from zero in either group. Nitrogen balance depended on impressive release of glutamine from the brain (-963 +/- 147 and -960 +/- 303 nmol/100 g/min), which amounted to 73% and 69% of net release in nondiabetic and IDDM subjects, respectively. We conclude that balance between uptake and release of amino acids is similar in nondiabetic and in long-term IDDM subjects.
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PMID:Brain uptake and release of amino acids in nondiabetic and insulin-dependent diabetic subjects: important role of glutamine release for nitrogen balance. 153 41

Thalidomide, a derivative of glutamic acid, has immunosuppressive effects and suppresses graft-vs-host disease in the rat and following bone marrow transplantation in man. It is effectively used in the treatment of erythema nodosum leprosum and has a potential therapeutic effect in a variety of autoimmune diseases. In view of these observations, we evaluated the effect of thalidomide on the incidence of spontaneous and iodine-induced lymphocytic thyroiditis and spontaneous insulin dependent diabetes mellitus in the BB/Wor rat. Thalidomide did not suppress the incidence of lymphocytic thyroiditis and serum anti-thyroglobulin antibodies or affect the serum concentrations of T4, T3 and TSH in this rat model. Thalidomide also did not affect the incidence of insulin dependent diabetes mellitus. In contrast to preliminary studies in man and rat demonstrating efficacy in the therapy of autoimmune diseases, thalidomide did not prevent or suppress autoimmune lymphocytic thyroiditis or insulin-dependent diabetes mellitus in the BB/Wor rat.
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PMID:Effect of thalidomide on the incidence of iodine-induced and spontaneous lymphocytic thyroiditis and spontaneous diabetes mellitus in the BB/Wor rat. 238 27

Although it has been confirmed that insulin dependent diabetes mellitus (IDDM) is a kind of autoimmune disease, islet cell autoantibodies (ICAs), insulin autoantibodies (IAA) and anti-GAD-glutamic acid decardaxylase antibodies have been found in the sera of patients with IDDM and immunotherapies have been used in some patients with IDDM, yet the manner in which the dysfunctional immunosystem acts on beta cells and causes damage to them remains to be clarified. Recently, possible involvement of the abnormal production of IL-6 in autoimmune symptoms was suggested in patients with cardiac myxomas, Castleman's disease and rheumatoid arthritis. However reports of IL-6 abnormal production in patients with IDDM are rare. In the present study, we examined whether or not an abnormal expression of IL-6 mRNA was present in mononuclear cells (PBMNCs) of the peripheral blood of patients with IDDM. We devised a highly sensitive, specific and semiquantitative protocol, ie, reverse transcription and polymerase chain reaction (RT-PCR). We have used such an assay to measure the relative expression levels of IL-6 mRNA in PBMNCs from 12 early IDDM patients (duration < 6 mon, 8.20 +/- 3.85 yr), 29 newly-diagnosed NIDDM patients (54.85 +/- 9.12 yr), 23 normal children (8.20 +/- 3.26 yr) and 12 normal adults (31.92 +/- 11.22 yr). In this assay significantly high expression levels of IL-6 mRNA were found in PBMNCs from patients with IDDM (P < 0.05). The relative levels were 0.91 +/- 0.19; 0.10 +/- 0.06; 0.43 +/- 0.08; 0.10 +/- 0.07, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Expression levels of IL-6 mRNA in PBMNCs from patients with IDDM, NIDDM and normals by RT-PCR procedure. 814 5

Glutamic acid decarboxylase (GAD) catalyzes formation of gamma-aminobutyric acid from glutamic acid and is a major autoantigen in insulin-dependent diabetes mellitus. Its two isoforms, GAD65 and GAD67, are encoded by two separate genes. We prepared human islet cDNA library and screened it with cDNA probes of rat brain GAD67. We cloned the cDNA for GAD67, the large isoform of glutamic acid decarboxylase, and determined its nucleotide sequence. Sequencing of the resulting clone identified a 1,785 residue open-reading frame encoded a 594 amino acid polypeptide that showed a 99.4% similarity with GAD67 from human brain. The bacterially expressed human islet GAD67 protein was enzymatically active and immunoreactive. The isolation of cDNA for this additional islet GAD isoforms will be important in studying the etiology and pathogenesis of IDDM.
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PMID:Cloning and expression of large isoform of glutamic acid decarboxylase from human pancreatic islet. 850 3

We describe a new method for measuring autoantibodies (Ab) to the 65 kDa isoform of glutamic acid carboxylase (GAD65). In particular, GAD65 without the hydrophobic N-terminal region has been produced in yeast, purified, labelled with 125I and reacted with GAD65 Ab. Antibody bound 125I-GAD65 is then precipitated by the addition of solid phase protein A. With the assay, GAD65 Ab were detected in 59 of 71 (83%) islet cell antibody (ICA) positive IDDM patients and in 8 of 23 (35%) ICA negative IDDM patients (overall 67 of 94 (71%) of IDDM patients). Low concentrations of GAD65 Ab were also detected in 2/98 (2%) healthy blood donors and 1/27 (4%) Graves' disease patients had a high level of antibody. GAD65 Ab were not detected in any of 10 Hashimoto's thyroiditis, 20 Addison's disease or 19 myasthenia gravis sera. There was good agreement between the 125I assay and the current reference method based on 35S-labelled full-length GAD65 (produced by in vitro transcription/translation reaction) and solid phase protein A (r = 0.91, n = 108). Overall, our 125I assay showed sensitivity, precision and disease group specificity at least as good as any assay so far described. These features, combined with a simple assay protocol and the convenience of 125I counting and handling indicate that the method is suitable for routine GAD65 Ab measurements.
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PMID:Glutamic acid decarboxylase autoantibody assay using 125I-labelled recombinant GAD65 produced in yeast. 902 28

Type I diabetes is an autoimmune and a polygenic disease, in which MHC-class II genes contribute to 48% of the disease. The aim of the present study, is to provide a guideline to understanding the molecular association of these genes, through the immunogenetic analysis of 3 Latin american mestizo populations. We included 606 individuals, 349 patients with DMDI and 257 healthy controls coming from 3 geographical areas: Mexico City, Mexico; Caracas, Venezuela and Medellin, Colombia. The results clearly indicate that in mestizo groups, the diabetogenic haplotypes are from mediterranean ancestry, while protection is due to Amerindian genes. It was demonstrated that the relevant sequences for IDDM expression are located to DRB1 and DQB1 loci with a minimal contribution of DQA1 residues. The sequences determining peptide recognition and the induction of TH1 cells mediating the cellular autoimmune response are in positions DRB1-57 and 74 (an aspartic acid and a glutamic acid respectively, confer protection), modulated by D-57 in the DQ, 8 chain. These data show that DRB1-DQB1 haplotypes are central for IDDM expression and open new pathways for the disease management.
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PMID:[High- and low-risk molecular sequences in autoimmune diseases. An analysis of type I diabetes in Latin America]. 950 14

Pancreatic beta-cells are more sensitive to several toxins (e.g., streptozotocin, alloxan, cytokines) than the other three endocrine cell types in the islets of Langerhans. Cytokine-induced free radicals in beta-cells may be involved in beta-cell-specific destruction in type 1 diabetes. To investigate if this sensitivity represents an acquired trait during beta-cell maturation, we used two in vitro cultured cell systems: 1) a pluripotent glucagon-positive pre-beta-cell phenotype (NHI-glu) that, after in vivo passage, matures into an insulin-producing beta-cell phenotype (NHI-ins) and 2) a glucagonoma cell-type (AN-glu) that, after stable transfection with pancreatic duodenal homeobox factor-1 (PDX-1), acquires the ability to produce insulin (AN-ins). After exposure to interleukin (IL)-1beta, both of the insulin-producing phenotypes were significantly more susceptible to toxic effects than their glucagon-producing counterparts. Nitric oxide (NO) production was induced in both NHI phenotypes, and inhibition with 0.5 mmol/l N(G)-monomethyl-L-arginine (NMMA) fully protected the cells. In addition, maturation into the NHI-ins phenotype was associated with an acquired dose-dependent sensitivity to the toxic effect of streptozotocin. Our results support the hypothesis that the exquisite sensitivity of beta-cells to IL-1beta and streptozotocin is an acquired trait during beta-cell maturation. These two cell systems will be useful tools for identification of molecular mechanisms involved in beta-cell maturation and sensitivity to toxins in relation to type 1 diabetes.
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PMID:Beta-cell maturation leads to in vitro sensitivity to cytotoxins. 1058 Apr 20

Development of diabetes mellitus caused by pancreatic beta-cell destruction of autoimmune origin is the result of a long lasting process. The most easily examinable feature of this stage is the occurrence of the islet cell antibodies. The sera which are positive for islet cell cytoplasmic antibodies (ICA), examined by indirect immunofluorescence, contain a mixture of antibodies. The glutamic acid decarbocylase (GAD), the tyrosin phosphatase (IA2), the insulin, and the GM2-1 glycolipid can be the targets of these antibodies. One can routinely examine the ICA, the GADA, the IA2 antibodies. The detection of antibodies against insulin (IAA) and GM-2-1 glycolipid is not invented in the routine laboratory work. The aim of the authors was the evaluation of clinical significance of occurrence of islet cell antibodies: one hundred and eighteen nondiabetic children an adult human being without known diabetic first degree relatives and 366 type 1 diabetic children and adult patients served as controls. The authors evaluated the predictive value of the different islet cell antibodies to the development of type 1 diabetes mellitus in 596 nondiabetic children with type 1 diabetic first degree relatives. The authors looked for markers of beta-cell destruction among sera of 320 diabetics manifested after 30 years of age with at least half a year of non-insulin-dependency and in the sera of 68 females suffered from gestational diabetes after 0-14 years of the index pregnancy. Finally the authors report 7 cases in which the examination of islet cell antibodies helped the diagnosis and classification of diabetes mellitus. Indirect immunofluorescence method was used for the detection of ICA, radioimmunoassay for that of GADA and IA2 antibodies. There was no positive reaction for ICA and GADA in the nondiabetic population without diabetic first degree relatives. Among the freshly diagnosed type 1 diabetic children 39% were positive for only ICA, 44% for only GADA and 80% for any antibodies. Among the freshly manifested type 1 diabetic adults ICA positivity only was observed in 21%, GADA positivity only in 7.1% and 93% for any antibodies. From the 595 nondiabetic children with type 1 diabetic first degree relatives 23 were positive for ICA, from whom 5 became diabetic during a two years observation period. These diabetic children had multiplex autoantibodies besides ICA. One child from this group, who was negative for ICA became diabetic, too. Among type 2 diabetic patients 13% were positive for ICA alone, 17% were positive for GADA alone and 27% were positive for any antibodies. The insulin dependency manifested in a short time was associated with antibody positivity. Among the gestational diabetics 10 were found positive for ICA. From them, 7 were type 1 diabetics, and 3 were type 2 diabetics at the time of the detection of antibodies. The authors suggest the need of determination of islet cell antibodies in the group of nondiabetic first degree relatives of type 1 diabetic patients (ICA, GADA, IA2 and IAA), in the group of non-insulin-dependent diabetics (ICA and GADA) as a screening for later insulin dependency, and in gestational diabetes after delivery (ICA) as screening for type 1 diabetes mellitus.
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PMID:[Detection of antibodies against pancreatic islet cells in clinical practice]. 1064 15

Antibodies to glutamic acid decarboxilase (GAD-Abs) are present in the serum of 60-80% of newly diagnosed type 1 diabetes (DM1) patients and patients with autoimmune polyendocrine syndrome (APS) associated with DM1. Higher titre of GAD-Abs are also present in the serum of 60% of patients with stiff-man syndrome (SMS) and all reported patients with cerebellar ataxia associated with polyendocrine autoimmunity (CAPA). Several studies suggest that GAD-Abs may play a critical role in the pathogenesis of SMS and CAPA but little is known about T-cell responsiveness to GAD-65 in these neurological diseases. To analyse cell-mediated responses to GAD, we studied the peripheral blood lymphocyte proliferation and cytokine responses to recombinant human GAD-65 in 5 patients with SMS, 6 with CAPA, 9 with DM1, 8 with APS and 15 control subjects. GAD-65-specific cellular proliferation was significantly higher in SMS than in CAPA, DM1, APS or controls. In contrast, only T cells from CAPA patients showed a significantly high production of interferon-gamma after GAD stimulation, compared to all other patients and controls. No differences were found for IL-4 production. These results suggest that, despite similar humoral autoreactivity, cellular responses to GAD are different between SMS and CAPA, with a greater inflammatory response in CAPA, and this difference may be relevant to the pathogenesis of these diseases.
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PMID:T-cell reactivity to glutamic acid decarboxylase in stiff-man syndrome and cerebellar ataxia associated with polyendocrine autoimmunity. 1219 88

The objective of this study was to test whether maternal age at delivery, child's birth order, cesarean section, complicated delivery, maternal smoking during pregnancy, or neonatal jaundice predict islet autoimmunity in children at genetically increased risk of type 1 diabetes in a birth cohort with blood draws at ages 9, 15, and 24 months and yearly thereafter. Newborns with diabetes-associated human leukocyte antigen genotypes (n = 938) and offspring or siblings of persons with type 1 diabetes (n = 428) from the Denver, Colorado, metropolitan area were examined from January 1994 to February 2003. Information on perinatal factors was collected by using questionnaires soon after the birth. Islet autoimmunity was defined as positivity for > or = 1 autoantibody to glutamic acid decarboxylase65, insulin, or protein tyrosine phosphatase-2/ICA512 at > or = 2 consecutive visits (n = 52; mean follow-up, 3.9 years). Complicated delivery (breech, forceps, vacuum extraction) predicted a higher risk of islet autoimmunity (hazard ratio = 2.10, 95% confidence interval: 1.09, 4.05). Increasing maternal age was related to risk of islet autoimmunity among first-degree relatives of persons with type 1 diabetes (hazard ratios = 3.96 and 8.88 for maternal ages 25-34 and > or = 35 years, respectively, compared with < 25 years; p for trend = 0.008. Other factors evaluated were not related to risk of islet autoimmunity. In conclusion, influences in utero or during delivery may affect the fetal immune system.
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PMID:Perinatal factors and development of islet autoimmunity in early childhood: the diabetes autoimmunity study in the young. 1522 11


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