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)

Several components of the erythrocyte-dependent glutathione redox system (reduced glutathione, GSH; oxidized glutathione, GSSG; glutathione peroxidase, GSH-Px; glutathione reductase, GSH-Red) were determined in patients with types I and II diabetes mellitus (DM). All groups studied were male subjects: G1, 20 young healthy individuals (aged 23.7 +/- 4.2 years); G2, 15 young insulin-treated type I DM patients; G3, 20 older insulin-treated type II DM patients; G4, 21 older oral hypoglycemic agent-treated type II DM patients; G5, 28 aged healthy individuals (aged 68.9 +/- 11.5 years). There were no differences between G1 and G2, G3 or G4 regarding erythrocyte GSH, GSSG, and GSH-Red (without FAD) levels. GSH-Px activity was significantly lower in G2 when compared to G1 (15.2 +/- 4.9 vs 20.6 +/- 6.6 IU/g Hb). The GSH-Red and GSH-Px activities and GSH levels were significantly higher in G3 (4.6 +/- 1.7 IU/g Hb, 20.2 +/- 8.7 IU/g Hb and 3.5 +/- 1.3 microM/g Hb) and G4 (5.0 +/- 2.2 IU/g Hb, 16.9 +/- 6.1 IU/g Hb and 5.0 +/- 2.3 microM/g Hb) when compared to G5 (3.4 +/- 0.9 IU/g Hb, 12.0 +/- 3.6 IU/g Hb and 2.3 +/- 0.9 microM/g Hb). The findings suggest that treatment of DM can stimulate the redox activity of red blood cells in aged subjects.
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PMID:Influence of diabetes mellitus on the glutathione redox system of human red blood cells. 134 8

The defense system of aortic endothelial cells against oxidative stress was studied in alloxan-induced diabetic rabbits, and the effect of insulin on the antioxidant activities was estimated. Endothelial cells were prepared from 10 diabetic rabbits, 18 diabetic rabbits treated with insulin, and 10 age-matched controls after 17 days of diabetes. These cells were used for the estimation of glutathione (GSH) levels and its related enzyme activities. The antioxidant activities in these endothelial cells from diabetic rabbits were compared with those from control subjects. The concentration of GSH decreased in diabetic rabbits (1.6 +/- 0.2 nmol/mg protein [mean +/- SD] v 3.7 +/- 0.6 nmol/mg protein). Decreases in the activities of Cu, Zn-superoxide dismutase (Cu,Zn-SOD) (62.7 +/- 11.0 U/mg protein v 172.9 +/- 20.2 U/mg protein), catalase (7.6 +/- 2.1 U/mg protein v 12.3 +/- 3.2 U/mg protein), and GSH peroxidase (134.0 +/- 27.0 mU/mg protein v 179.1 +/- 26.2 mU/mg protein) were observed. The activities of other GSH-related enzymes such as GSH S-transferase or GSH reductase did not change in endothelial cells from diabetic rabbits. Most of these antioxidant activities were prevented when diabetic rabbits were treated with insulin (1 to 2 U/kg/d). These antioxidant activities were also determined in the diabetic liver and kidney. Similar decreases in the cellular defense activities and prevention of the decrease in activities by insulin were observed in the diabetic liver, while these antioxidant enzyme activities in the kidney were resistant to diabetic conditions.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of insulin on impaired antioxidant activities in aortic endothelial cells from diabetic rabbits. 140 92

The paper reviews published data on the products of platelet lipid peroxidation, their role in blood coagulation as other physiological and pathological processes. The authors discuss the significance of anti-oxidants (selenium, glutathione peroxidase, reduced glutathione and vitamin E) in removing excessive hydroperoxides and thus in the control of platelet functional activity. Changes in platelet arachidonic acid metabolites and in antioxidants were found in a number of pathological conditions such as diabetes mellitus and cardiovascular diseases.
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PMID:[Blood platelets, lipid peroxidation and antioxidants]. 147 66

Studies from several laboratories suggest that oxidized LDL may play an important role in atherogenesis. Our group previously showed that treatment of aortic endothelial cells with low levels of MM-LDL caused increased expression of MCP-1, M-CSF, tissue factor, and a monocyte-binding protein. In these studies MM-LDL was produced by storage of native LDL. We now show that cocultures of endothelial and smooth muscle cells can also produce MM-LDL from native LDL. This production of MM-LDL by cells is prevented by preincubating the LDL with probucol or vitamin E. However, addition of antioxidants to MM-LDL did not block its action. In past studies we also showed that endothelial cells exhibit differential sensitivity to the effects of MM-LDL. We report herein that in resistant cells there is no elevation of catalase, glutathione peroxidase, or copper-zinc-dependent SOD. However, manganese-dependent SOD is elevated in resistant cells. Ways in which MM-LDL production may be elevated in poorly controlled diabetics subjects are discussed.
Diabetes 1992 Oct
PMID:Minimally modified lipoproteins in diabetes. 152 40

Lipid peroxidation and the antioxidant status were studied in male patients having stable angina (SA) and unstable angina (UA) pectoris and the results were compared with that of controls. Lipid peroxides (LPx) and conjugated dienes (CD) were found to be elevated in patients with both SA (LPx: 3.96 +/- 1.07, P less than 0.001; CD: 357.09 +/- 66.23, P less than 0.01) and UA (LPx: 4.66 +/- 1.33, CD: 373.33 +/- 49.82, P less than 0.001) than in controls (LPx: 3.22 +/- 0.86, CD: 335.15 +/- 60.27). In SA, the erythrocytes expressed a diminished activity of superoxide dismutase (SOD) (SA: 435.59 +/- 76.02, control: 651.69 +/- 145.90, P less than 0.001) and normal activities of catalase and glutathione peroxidase, whereas in UA it showed enhanced activities of both SOD (UA: 735.72 +/- 145.67, P less than 0.01) and catalase (UA: 21.94 +/- 6.26, control: 18.69 +/- 6.37, P less than 0.01). A significant increase was also noticed in the levels of ceruloplasmin and vitamin E during both types of angina, but not alteration was observed in the levels of transferrin. Further, the patients with diabetes showed maximum levels of lipid peroxides compared to smokers and hypertensives. The level of lipid peroxides was also observed to increase with the severity of disease. This study indicates that free radicals are involved in the pathogenesis and progression of atherosclerotic heart disease.
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PMID:Antioxidant status in relation to free radical production during stable and unstable anginal syndromes. 163 72

The interaction of endothelium-derived relaxing factor (EDRF) and oxygen-derived free radicals may potentially play an important role in the pathophysiology of complications associated with diabetes. In the present study, we investigated spontaneous EDRF release in diabetic rat aorta that is unmasked by the addition of superoxide dismutase (SOD). SOD produced a significantly greater relaxation in diabetic aorta compared with control aorta using both aortic ring and bioassay preparations. This relaxation was unaltered by pretreatment with catalase or indomethacin. Removal of the endothelium or pretreatment with either NG-monomethyl-L-arginine or methylene blue eliminated SOD-induced relaxation in both control and diabetic rings. Measurement of antioxidant enzymes revealed an elevation in catalase in diabetic aorta, with no difference in the SOD or glutathione peroxidase activity. The increase in catalase activity suggests increased exposure of diabetic aorta to hydrogen peroxide. Pretreatment of rings with the catalase inhibitor, 3-amino-1,2,4-triazole, attenuated the SOD-induced relaxation in diabetic aortic rings but had no effect in control aortic rings. In summary, our observations suggest that the diabetic rat aorta releases more spontaneous EDRF than control aorta; however, the activity of EDRF on vascular smooth muscle tone is masked by increased destruction by oxygen-derived free radicals.
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PMID:Regulation of spontaneous EDRF release in diabetic rat aorta by oxygen free radicals. 163 63

The metabolism of glutathione and activities of its related enzymes were investigated in erythrocytes from patients with diabetes mellitus. A decrease in the levels of the reduced form of glutathione and an increase in the levels of glutathione disulfide were observed in erythrocytes from diabetics whose fasting plasma glucose was more than 140 mg/dl. The activity of glutathione reductase decreased in diabetics, while that of glutathione peroxidase did no change. ATP-depended outward transport of glutathione disulfide also decreased in diabetics. These data suggest that the increase in the levels of glutathione disulfide in erythrocyte from diabetics is brought about by the decreased transport activity of glutathione disulfide through the erythrocyte membrane together with a decrease in the activity of glutathione reductase. The activity of gamma-glutamylcysteine synthetase was significantly lower in diabetics than in normal controls. Glycated gamma-glutamylcysteine synthetase determined using a boronate affinity column chromatography was higher in diabetics than in normal controls. The rate of glutathione synthesis using (H3)-glycine decreased in diabetics. The decrease is the levels of reduced form of glutathione is erythrocytes of diabetics is thought to be brought about by impaired glutathione synthesis. In order to study the mechanism by which glutathione synthesis is impaired, gamma-glutamylcysteine synthetase was purified from human erythrocytes. The molecular weight of the purified enzyme was 60K. A single band was observed on SDS polyacrylamide gel electrophoresis. When the purified enzyme was incubated with glucose, the enzyme activity decreased dependent on the incubation time. These data suggest that the impaired glutathione synthesis in diabetics is brought by glycation of gamma-glutamylcysteine synthetase. As conclusion, glutathione metabolism is impaired in erythrocytes from diabetics which weaken the defence mechanism against oxidative stress in these patients.
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PMID:[Glutathione metabolism in erythrocytes from patients with diabetes mellitus]. 167 80

Lipid peroxide (LPO) values in blood plasma, along with the glutathione peroxidase (GSH-PX) activity in whole blood and superoxide dismutase (SOD) activity in erythrocytes were determined in 50 patients with non-insulin-dependent diabetes mellitus (NIDDM) and in 33 control subjects. The mean LPO value, SOD activity, LPO/GSH-PX and LPO/SOD ratios in the diabetic patients were significantly higher than those in the control subjects. The increases of LPO value, LPO/GSH-PX and LPO/SOD ratios were more pronounced in diabetics with microangiopathy than in those without microangiopathy. Our results suggest that free radicals may be implicated in the pathogenesis of diabetic microangiopathy.
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PMID:[Relationship between free radicals and diabetic microangiopathy]. 175 51

Oxidative biotransformation of xenobiotics and endogenous substances involves glutathione in reduced form as an integral component through two mechanisms: glutathione peroxidase catalysing the reduction of hydrogen peroxide and organic hydroperoxides, and glutathione-S-transferases catalysing the conjugation of oxygenated derivatives with glutathione. We studied glutathione and glutathione-related enzyme activities in haemolysed venous blood samples from 49 healthy children and from 11 children with diabetes mellitus, 10 children with rheumatoid arthritis, seven children with active coeliac disease, and seven children with acute lymphoblastic leukaemia. Among the healthy children glutathione content and the activities of glutathione reductase, glutathione peroxidase, and glutathione-S-transferase were unrelated to sex; age-dependent differences were also minor. The patients with diabetes mellitus had decreased activity of glutathione reductase. The patients with acute lymphoblastic leukaemia had increased activity of both glutathione peroxidase and glutathione-S-transferase, possibly reflecting an adaptive response to free-radicals. The patients with active coeliac disease had control levels of all measured parameters of glutathione-related reactions indicating, since we earlier found decreased activities of glutathione peroxidase in intestinal mucosa of celiacs, that blood may not always reflect tissue-specific changes.
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PMID:Glutathione and glutathione-metabolizing enzymes in the erythrocytes of healthy children and in children with insulin-dependent diabetes mellitus, juvenile rheumatoid arthritis, coeliac disease and acute lymphoblastic leukaemia. 204 16

Superoxide dismutase, glutathione peroxidase and glutathione reductase activities were measured in erythrocytes of 214 young patients with insulin-dependent diabetes and 37 healthy subjects with similar age and sex distribution. The diabetic patients were divided into groups and subgroups according to sex, age, duration of disease, existence of diabetes complications and family history of atherogenic risks. Data analysis was performed by comparing enzyme activities in subgroups according to the degree of diabetes control and the plasmatic level of various lipid fractions. Results showed that superoxide dismutase, glutathione peroxidase and glutathione reductase activities in young diabetic patients were similar to those in controls, except for patients with retinopathy, whose glutathione peroxidase activity was decreased. This last finding might suggest that there is a relationship between the development of diabetic microvascular complications and the accumulation of free radicals and peroxide lipids.
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PMID:[Antioxidant enzymes in insulin-dependent diabetes in the child and adolescent]. 208 81


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