Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Insulin stimulates the production of superoxide and hydrogen peroxide in various tissues. Hydrogen peroxide has been proposed to be an intracellular second messenger for insulin and a moderator of cellular proliferation and differentiation. We previously found that cell proliferation is increased in small intestinal mucosa of streptozotocin-diabetic rats. The current study was undertaken to determine if superoxide dismutase (SOD), the enzyme that converts superoxide to hydrogen peroxide, is altered in the mucosa of the alimentary tract and renal cortex of the diabetic rat, and if so, whether SOD responds to insulin treatment. Total SOD and cyanide-insensitive [manganese-containing SOD (Mn SOD)] SOD were measured by the nitroblue tetrazolium inhibition assay. We studied ad libitum fed animals, where diabetics are hyperphagic and pair-fed animals, where hyperphagia is not present. Since cyclic nucleotides appear to control cell proliferation in some tissues, we also measured cAMP and cGMP in mucosa of the small intestine. In ad libitum fed animals, total SOD was depressed in the mucosa of duodenum, jejunum, and ileum, but not in the cecum or colon of the streptozotocin-diabetic rats. The level of Mn-SOD was not affected by diabetes or insulin treatment, but the cyanide-sensitive [copper- and zinc containing SOD (Cu-Zn SOD] SOD was depressed in the small intestine and colon of diabetic rats. Insulin treatment restored total and Cu-Zn SOD activity in the small intestine to normal and increased Cu-Zn SOD activity in the colon to normal. Pair-fed animals showed the same changes in the SOD activity of jejunal mucosa that were found in ad libitum fed animals. In renal cortex, diabetes did not alter total SOD, but increased Mn SOD and decreased Cu-Zn SOD. Both responses were reversed by insulin treatment. Cyclic nucleotide concentrations were not affected by diabetes. We conclude that SOD enzymes re altered in diabetes, at least in proliferating tissues. Responses are tissue specific. The mucosa of the small intestine and colon show decreased Cu-Zn SOD, the SOD of the cecum is unaffected, and the kidney shows increased Mn SOD and decreased Cu-Zn SOD. The SOD responses of diabetics are reversed by insulin treatment.
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PMID:Superoxide dismutase activity in the intestine of the streptozotocin-diabetic rat. 704 72

We studied the effect of supplementation with vitamins C, E and beta-carotene (PARABION, produced by Syndipharma) on antioxidative status in kidneys of male Wistar rats with diabetes induced by intravenous application of streptozotocin (45 mg.kg-1 of body weight). The animals received subtherapeutic doses of Insulin Interdep (6 U.kg-1 of body weight). A significant decrease of malondialdehyde (MDA), reduced (GSH) and oxidized (GSSG) glutathione and reduction of the activities of Se-glutathione peroxidase (Se-GSH-PX, EC. 1.11.1.9.) and glutathione S-transferase (GST, EC. 2.5.1.18.) were observed in kidneys of diabetic rats treated with these vitamins. On the contrary, the activity of CuZn-superoxide dismutase (CuZn-SOD, EC. 1.15.1.1) and the level of vitamin C (vit. C) increased significantly. No changes were observed for vitamin E (vit. E), beta-carotene and catalase (CAT, EC. 1.11.1.6). Supplementation with vitamins C, E and beta-carotene resulted in an improvement of antioxidative status of kidneys of rats with streptozotocin-induced diabetes.
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PMID:Effect of intake of exogenous vitamins C, E and beta-carotene on the antioxidative status in kidneys of rats with streptozotocin-induced diabetes. 747 41

Experiments were performed to determine the influence of endogenous nitric oxide (NO) on basal arteriolar diameter in kidneys from diabetic rats and to evaluate the role of superoxide anions as modulators of NO activity under these conditions. Male Sprague-Dawley rats were injected with streptozotocin (STZ, 65 mg/kg i.v.) and received insulin via ip osmotic minipumps (3 U/kg per day). Sham rats received vehicle treatments. Videomicroscopy was used, in conjunction with the in vitro blood-perfused juxtamedullary nephron technique, to visualize renal afferent and efferent arterioles 2 wk after the onset of diabetes. Baseline afferent arteriolar inside diameter was greater in STZ (32 +/- 2 microns) than in sham rats (24 +/- 2 microns). Efferent arteriolar diameter did not differ between STZ (24 +/- 2 microns) and sham rats (21 +/- 1 microns). In kidneys from sham rats, N omega-nitro-L-arginine (L-NNA, an NO synthase inhibitor) decreased arteriolar diameters in a concentration-dependent manner, with 100 microM L-NNA significantly reducing both afferent (13 +/- 2%) and efferent (11 +/- 1%) diameters. In kidneys from STZ rats, 100 microM L-NNA reduced afferent and efferent diameters by only 3 +/- 1 and 4 +/- 1%, respectively, indicating a suppressed arteriolar influence of NO. In STZ kidneys treated with superoxide dismutase (SOD, 150 U/mL), afferent and efferent arteriolar L-NNA responses were restored to levels comparable to those of SOD-treated and untreated sham kidneys. These observations suggest that suppressed SOD activity reduces the tonic influence of NO on renal arterioles during the early stage of diabetes mellitus, perhaps through allowing the accumulation of NO-scavenging superoxide anions.
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PMID:Superoxide dismutase restores the influence of nitric oxide on renal arterioles in diabetes mellitus. 775 88

Extracellular-superoxide dismutase (EC-SOD) is a secretory glycoprotein that is the major SOD isozyme in extracellular fluids. It has previously been shown that EC-SOD levels in sera from healthy persons are clearly divided into two discontinuous groups: a lower group (named Group I, below 120 ng/ml) and a higher group (Group II, above 400 ng/ml). The family studies have shown that the high EC-SOD level in healthy persons is genetically transmitted. We report here on the EC-SOD levels in the sera of patients with various diseases. The EC-SOD levels were distinctly higher in patients with renal diseases and moderately higher in liver diseases and diabetes than those in normal healthy persons. In cerebrovascular diseases, heart diseases and acute digestive diseases, significant differences of EC-SOD were not observed. In patients with renal diseases, the increase of EC-SOD was accompanied by the lack of renal function. Serum EC-SOD in Group I healthy persons is known to be heterogeneous with regard to heparin affinity and can be separated into three fractions: A without affinity, B with weak affinity and C with relatively strong heparin affinity, whereas the EC-SOD in Group II is mainly one fraction of C-type. Also in the case of hemodialysis patients, serum EC-SOD in Group I or Group I' (approximately 120-400 ng/ml) was divided into three fractions. EC-SOD in Group II showed two different profiles on heparin-Sepharose column chromatographies: one consisted mainly of EC-SOD C and the other consisted of EC-SOD A and C. It is probable that the high serum EC-SOD level in hemodialysis patients was due to two possible factors: the genetic transmitted factor and unknown pathophysiological factor(s).
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PMID:Quantitative and qualitative changes of extracellular-superoxide dismutase in patients with various diseases. 798 42

An activity of erythrocyte SOD, HBA1C levels and FA activity have been determined in 17 patients with diabetes mellitus type I and 15 healthy subjects. It was found that the treatment of diabetes mellitus has no effect on the SOD activity.
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PMID:[Effect of diabetes mellitus therapy on activity of erythrocyte superoxide dismutase]. 800 69

A new and novel form of L-glutamate decarboxylase (GAD; EC 4.1.1.15) was purified from whole porcine brain to apparent homogeneity by a combination of column chromatographies on DE-52, ultragel AcA 34, hydroxylapatite and Sephadex G-200, and native gel electrophoresis. The purified GAD was established as an integral membrane protein based on hydrophobic interaction chromatography and membrane extraction studies. This membrane GAD (MGAD) has a native molecular weight of 120 +/- 5 kDa and is a homodimer of 60 +/- 2 kDa. Immunoprecipitation and immunoblotting tests using the sera from insulin-dependent diabetes mellitus (IDDM) patients revealed the presence of antibodies against this newly identified MGAD in IDDM. The role of MGAD in the pathogenesis of IDDM and related autoimmune disorders is also discussed.
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PMID:An integral membrane protein form of brain L-glutamate decarboxylase: purification, characterization and its relationship to insulin-dependent diabetes mellitus. 803 92

The aim of our research was elucidation of a relationship between red cell membrane lipid peroxidation (LPO) and antioxidant defense enzymes, on the one hand, and the age, disease duration, and presence of vascular complications in patients with type I diabetes mellitus, on the other. The possibility of correcting red cell peroxide status with human insulin preparations was investigated. Red cell membrane LPO was found increased more than twofold and antioxidant defense enzymes activities virtually unchanged vs. controls in 16 patients with diabetes aged 20 to 43. These characteristics of red cell peroxidation status do not depend on patients' age, disease standing, or presence of vascular complications. A twelve-week therapy with biosynthetic insulin resulted in complete normalization of LPO processes in patients with angiopathies aged under 35 and with disease standing of less than 10 years. In diabetics with angiopathies aged over 35 and disease standing of more than 10 years red cell MDA level reduced under the effect of therapy with human insulin preparations but was still increased vs. that in healthy donors by 1.5 times. Red cell GP and SOD activities reduced in the course of insulin therapy in all the examined groups of diabetics. Catalase activity increased by approximately 50% in patients with angiopathies, those aged over 35, and a disease standing of more than 10 years under the effect of insulin. In the rest groups of patients catalase activity did not differ from its initial level. Our results permit us recommending besides human insulin preparations antioxidant therapy for patients with vascular complications, those aged over 35, and a disease standing of more than 10 years.
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PMID:[Effect of biosynthetic insulin on lipid peroxidation in erythrocyte membranes in patients with type I diabetes mellitus]. 807 92

Diabetes was induced in rats by an injection of streptozotocin (55 mg/kg). Endothelium-dependent relaxations in mesenteric resistance arteries (luminal diameter 210 +/- 20 microns) of control and diabetic rats were compared in myographs. Acetylcholine induced endothelium-dependent relaxations that were mediated by nitric oxide (EDNO). EDNO-mediated relaxations were impaired in diabetic arteries; concentrations of acetylcholine required to produce 50% relaxation (ED50) of activated arteries were 5 nM in control and 13.5 nM in arteries from diabetic rats studied after 6 wk (P < 0.05). The impairment in relaxation worsened with duration of the diabetes; ED50 for acetylcholine increased to 63 and 100 nM in diabetic arteries studied after 16 and 24 wk of diabetes, respectively. NG-nitro-L-arginine produced 5.5- and 16-fold decreases in sensitivity of control and diabetic arteries to acetylcholine. NG-nitro-L-arginine produced at least as much inhibition of acetylcholine relaxations in diabetic arteries, indicating that the impaired relaxation noted in diabetic arteries does not result from decreased production of EDNO. EDNO-mediated relaxations in diabetic arteries were impaired by increased production of endothelium-derived free radicals. Superoxide dismutase, a scavenger of superoxide anion, and dimethylthiourea, a scavenger of hydroxyl radicals, normalized EDNO-mediated relaxations in diabetic arteries. The ED50 values for acetylcholine were 13.5, 5.5, and 4 nM for untreated and SOD- and DMTU-treated diabetic arteries, respectively (P < 0.05 for treated vs. untreated arteries). Superoxide anion and hydroxyl radicals appear to block EDNO-mediated relaxation by inactivating EDNO.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Endothelial dysfunction in mesenteric resistance arteries of diabetic rats: role of free radicals. 816 Aug 18

AH-9 is a compound with hypoglycemic action. AH-9 was also found to have antioxidant activity. The hemolysis, hemoglobin oxidation and lipid peroxidation of erythrocytes induced by hydrogen peroxide and Fe(++)-induced MDA formation of liver microsomes were inhibited by AH-9, and the activity of SOD and catalase were shown to be increased in normal and alloxan-diabetic mice after treatment with AH-9. The above results indicate that AH-9 might act as a scavenger of superoxide and might be useful for improving the pathophysiological state in diabetes mellitus and its complications.
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PMID:[The antioxidant action of AH-9]. 816 9

The effect of sodium metavanadate (NaVO3) consumption on trace element metabolism, components of the antioxidant defense system and lipid oxidative damage were studied in control (CON) and streptozotocin-induced diabetic (DIAB) rats. Ten days after injection, CON and DIAB rats received either 0 mM NaVO3/80 mM NaCl (0 group) or 1.2 mM NaVO3/80 mM NaCl (1.2V group) in their drinking water. DIAB groups had higher food and fluid intakes than the CON groups; vanadium (V) groups had lower food and fluid intakes than the saline groups. Vanadium therapy lowered plasma glucose concentrations of DIAB rats. The following parameters were similar among the groups: plasma Zn, Cu and Fe concentrations, plasma ceruloplasmin activity, liver Zn, Cu, Mn and Fe concentrations, kidney Mn and Fe concentrations, liver non-Se-dependent glutathione peroxidase (GSH-Px), glutathione reductase (GSH-Red) and Mn-SOD activities, liver reduced glutathione (GSH) and oxidized glutathione (GSSG) concentrations and kidney non-Se-dependent GSH-Px activity. Kidney Zn and Cu concentrations were higher in DIAB rats than in CON rats. The CON-1.2V and DIAB-1.2V groups had V accumulation in the liver and kidney. Liver CuZn-SOD and Se-dependent GSH-Px and kidney CuZn-SOD and GSH-Red activities were lower in DIAB rats compared to CON rats; kidney Mn-SOD and kidney Se-dependent GSH-Px activities were higher in DIAB rats than CON rats. Vanadium treatment did not cause significant alterations in the antioxidant defense system; however, tissue vanadium concentrations were positively correlated to TBARS production. These results show that diabetes caused significant alterations in the antioxidant defense system and that V therapy was associated with a marked deterioration in health of both control and diabetic rats.
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PMID:Vanadium treatment of diabetic Sprague-Dawley rats results in tissue vanadium accumulation and pro-oxidant effects. 824 40


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