Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0240066 (iron deficiency)
 7,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hemin allows maximal protein synthesis in intact rabbit reticulocytes and their cell-free lysate preparations by retarding the formation of a translational repressor (HCR) found in the postribosomal supernate. In order to evaluate the role of HCR in the pathogenesis of hypochromic anemias, HCR was isolated and partially purified from intact rabbit reticulocytes incubated in vitro with either 0.1 mM alpha,alpha-dipyridyl (an iron-chelating agent) or 0.1 M ethanol. Both of these agents inhibit reticulocyte protein synthesis. Hemin (50 muM) protects against the inhibition by both agents. A ferrous iron-transferrin mixture, however, protects only against alpha,alpha-dipyridyl. Both alpha,alpha-dipyridyl and ethanol inhibit heme synthesis before the time that protein synthesis is affected, while neither lowers either ATP or GSH levels. These results indicate that while both agents inhibit heme synthesis, alpha,alpha-dipyridyl does so by inducing iron deficiency while ethanol works at a non-iron-requiring step. When HCR was isolated from intact cells and assayed in the reticulocyte cell-free systems, plus and minus hemin, premature appearance of HCR was found in cells incubated in vitro with alpha,alpha-dipyridyl or ethanol. When hemin was present in the intact cell incubation, the appearance of HCR was retarded. The HCR from alpha,alpha-dipyridyl ethanol-treated cells was partially purified and eluted at the same location on a Sephadex G-200 column (molecular weight approximately 3 x 10(5)) as that from postribosomal supernates incubated minus hemin. In addition rabbits with phenylhydrazine-induced hemolytic anemia were given intravenous ethanol in vivo at a dose of 0.4 ml/kg. This concentration of alcohol resulted in an inhibition of the rate of heme synthesis and protein synthesis as well as an acceleration of HCR formation in reticulocytes. The HCR from these in vivo treated rabbits was isolated, partially purified, and assayed in an identical fashion as the in vitro experiments. These in vivo experiments further support the physiological and pathophysiological role of HCR in reticulocytes. On the basis of these results a model for a role of HCR in some of the hypochromic anemias is proposed. In iron deficiency or chronic disease (where iron is not available to the erythroblast for heme synthesis) HCR appears prematurely and inhibits protein synthesis. When heme synthesis is inhibited by ethanol but there is sufficient intracellular iron, HCR appears prematurely and inhibits protein synthesis, iron accumulates in the erythroblast, and the end result is sideroblastic anemia.
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PMID:A rabbit reticulocyte model for the role of hemin-controlled repressor in hypochromic anemias. 0 17

Erythrocytic glutathione-peroxidase (GSH-Px) activity and plasma selenium concentrations were measured in 14 patients: 7 with iron deficiency and 7 with raised serum iron levels. The decreased enzymatic activity in iron deficiency was confirmed. Plasma selenium was significantly lower in patients with lower serum iron; furthermore there is a significant correlation between serum iron and plasma selenium concentrations. Another correlation even more significant was found between plasma selenium and enzyme activity in all the cases we studied. These data suggests that the importance of iron for GSH-Px activity may be merely due to its relationship with selenium and that plasma selenium concentration may be of critical importance for enzyme activity.
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PMID:Erythrocytic glutathione peroxidase: its relationship to plasma selenium in man. 88 36

The erythrocyte glutathione metabolism of 11 children with acute celiac disease (CD), 11 children under gluten free diet with CD and 5 children with cow's milk allergy was compared to that of 11 children with nutritive iron deficiency and to 22 healthy children as controls. Erythrocyte glutathione (GSH) content of celiac children was elevated and the glutathione disulfide (GSSG) level was significantly decreased as compared to normal controls. Erythrocyte GSSG/GSH ratio in acute CD differed also from the one in iron deficiency. In vitro oxidative load of acetylphenylhydrazine proved the impaired glutathione stability of the erythrocytes in acute CD and cow's milk allergy. A parallel rise of methemoglobin and hemichrome level of blood cells was seen. Further on, the selenium content of the red blood cells of CD patients decreased. All alterations of the erythrocyte tended to normalize during the dietetic period. These data suggest a reduced protective capacity of erythrocytes in CD and in cow's milk allergy in childhood against oxidizing stresses.
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PMID:Decrease in the antioxidant capacity of red blood cells in children with celiac disease. 147 83

The response of glutathione peroxidase (GSH-Px) to dietary iron deficiency was studied in red blood cells and liver from male Sprague-Dawley rats. A casein-based purified diet containing 0.02 ppm Se and 7 ppm Fe was used as the basal diet. Rats were given the basal diet supplemented with either 0.5 ppm Se or 30 ppm Fe or both for 10 weeks. Food consumption in iron-deficient rats was 79% of controls. Iron deficiency caused a significant decrease of GSH-Px and catalase activities in red blood cells (RBC) expressed per cell. However, enzyme activities expressed per gram of hemoglobin or per milligram or protein increased. These data suggest that GSH-Px is present in adequate quantities in iron-deficient red blood cells to protect cell membranes and hemoglobin as long as the rats receive adequate Se. Hepatic catalase was not altered by iron or Se deficiency. Liver Se GSH-Px activity/g tissue decreased to 75% of control activity during iron deficiency. Non Se GSH-Px activity increased during Se or iron deficiencies and may compensate to a limited extent for decreased Se GSH-Px activity. In contrast to earlier reports, RBC GSH-Px activity was not altered by iron deficiency except for possible indirect effects related to changes in red blood cell size or food intake.
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PMID:Glutathione peroxidase activity in iron-deficient rats. 745 71

Chronic exposure of adult rats to dietary intake of cadmium (15 mg CdCl2/day/kg for 30 days) leads to development of anemia and thrombocytosis. Anemia is characterized by significant reticulocytosis (13.1 +/- 1.0%), anysocytosis, poikilocytosis, iron deficiency and marked alterations of antioxidant and metabolic status of red blood cells. Activities of SOD, catalase, GPx and GR were significantly increased in red blood cells of cadmium-treated rats. In treated animals cadmium induced an increase of red cell reduced and oxidized glutathione with no changes of GSSG/GSH ratio. However, significant reduction of lipid peroxidation was found. Plasma levels of tocopherol and ascorbate, as well as activity of glutathione-S-transferase, were all significantly increased in cadmium-treated rats. The energy metabolism of red blood cells was deeply altered in cadmium-treated rats. The levels of ATP, ADP, AMP and TAN were significantly increased while ATP/ADP ratio and adenylate energy charge (AEC) were significantly reduced. The level of 2,3-BPG was somewhat lower, but 2,3-BPG/Hb ratio was considerably higher, in red blood cells of cadmium-treated rats.
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PMID:Cadmium-induced changes of antioxidant and metabolic status in red blood cells of rats: in vivo effects. 837 Apr 23

Ionizing radiation is currently used for prevention of transfusion associated graft versus host disease (TAGVHD). As radiation damage is associated with the production of activated oxygen species, the aim of this study was to observe the immediate effect of ionizing radiation on red cell membrane and intracellular oxidative defense systems. Neonatal and iron deficiency (IDA) cells, known for their increased sensitivity to oxidative stress, were chosen and compared with normal cells. Irradiation was performed in doses of 1500 cGy, 3000 cGy and 5000 cGy. GSH and methemoglobin levels and the activity of different antioxidant enzymes, measured under optimal in vitro conditions, were preserved in all cells after irradiation. Only radiation at the highest does of 5000 cGy, caused significant potassium leakage in neonatal cells and insignificant increase in IDA cells. Thus, cells with increased sensitivity to oxidative stress are more susceptible to damage by ionizing radiation than normal cells.
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PMID:Effect of radiation on red cell membrane and intracellular oxidative defense systems. 872 21

Redox-active forms of iron are known to catalyze free radical mediated peroxidative reactions. There is scanty information on such effects at the sites of iron absorption. This was tested in iron-deficient WKY female rats supplemented for 15 days with FeSO4 equivalent to 8 mg of iron (D+) and compared with iron deficient (D) and iron adequate (C) rats. The levels of intestinal MDA and protein carbonyls and the activities of various antioxidant enzymes were estimated. As markers of functional integrity, the activities of alkaline phosphatase and Lys-Ala-dipeptidyl aminopeptidase were evaluated. In addition, we measured the concentrations of ferritin, transferrin, and ceruloplasmin levels in serum and in intestinal mucosa. It was observed that correction of iron deficiency resulted in significant increase in MDA and protein carbonyl formation. Activities of both alkaline phosphatase and Lys-Ala-dipeptidyl aminopeptidase were significantly decreased in D+ compared to C. The increase in catalase and decrease in Gpx was found to be sensitive to iron administration. Neither iron deficiency nor its correction had any effect on the activity of SOD and GSH levels. Iron supplementation has resulted in decreased mobilization of stored iron as reflected by increased mucosal ferritin level and decreased serum ceruloplasmin ferroxidase activity contributing to greater peroxidative stress in the intestine. These results suggest that iron-deficient intestine of rat is more susceptible to iron-mediated peroxidative damage and functional impairment during correction of deficiency with iron.
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PMID:Iron-deficient intestine is more susceptible to peroxidative damage during iron supplementation in rats. 980 Oct 65

Aluminum, a trivalent cation unable to undergo redox reactions, has been linked to many diseases such as dialysis dementia and microcytic anemia without iron deficiency. It has also been implicated in Alzheimer's disease although this is controversial. Because cell death due to oxidative injury is suspected to be a contributory factor in many neurological diseases and aluminum neurotoxicity, glioma (C-6) and neuroblastoma (NBP2) cells were utilized to assess early changes in oxidative parameters consequent to a 48-h exposure to aluminum sulfate. A 500-microM concentration of this salt produced a significant increase in reactive oxygen species (ROS) production and a significant decrease in glutathione (GSH) content in glioma cells. However, the same concentration of the aluminum salt did not lead to any significant changes in the neuroblastoma cells. Mitochondrial respiratory activity in glioma cells was also found to be significantly higher in the aluminum treated cells. As judged by morin-metal complex formation, aluminum can enter glioma cells much more readily than neuroblastoma cells. Thus, it is possible that the cerebral target following an acute exposure to aluminum may be glial rather than neuronal.
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PMID:Aluminum-induced oxidative events in cell lines: glioma are more responsive than neuroblastoma. 1038 Nov 87

Dietary copper- and iron restriction was achieved by application of the whole milk diet to growing rats in the course of 50 days. Three distinct responses of cytosolic and mitochondrial aconitases as well as of antioxidant defense system (CuZnSOD, MnSOD, catalase and GSH) to the dietary copper- and iron deficiency were established in liver, kidney and heart from experimental rats. The results were discussed with a view to the participation of ROS-generating processes in copper- and iron-deficient state. Differences in oxidative stability of cytosolic and mitochondrial aconitase activity of both control and experimental rats were also found. The in vitro increased aconitase activity of cytosol and the unchanged one of mitochondria from liver upon exposure of preparations to air were proved in vivo upon dietary copper- and iron restriction. This finding was interpreted to suggest the existence of putative aconitase activity.
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PMID:Effect of dietary copper and iron restriction on aconitase activity and antioxidant capacity of liver, kidney and heart from growing rats. 1114 Jan 69

The risk of oral cavity cancer was determined in relation to serological levels of iron; vitamins A, B2, C, E; zinc; thiamin; and glutathione (GSH). The study included 65 hospitalized patients with oral cancer and 85 matched controls. In comparing the highest to the lowest tertiles, the risk was odds ratio (OR) = 0.3 [95% confidence interval (CI) = 0.1-0.6] for iron; 3.2 (95% CI = 1.3-8.1) for total iron binding capacity (TIBC), which measures the concentration of the iron delivery protein transferrin; and 0.4 (95% CI = 0.2-0.9) for transferrin saturation (iron/TIBC x 100). These associations were stronger in never smokers than in ever smokers. The risk associated with the iron storage protein ferritin was significantly elevated, but this association could reflect disease-related inflammation or comorbidity. The OR for GSH was 0.4 (95% CI = 0.1-0.9), and the OR for GSH reductase activity coefficient (indicative of riboflavin deficiency) was 1.6 (95% CI = 1.3-3.7). These findings suggest that mild iron deficiency and low GSH levels, which are associated with increased oxidative stress, increase the risk of oral cavity cancer.
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PMID:Blood iron, glutathione, and micronutrient levels and the risk of oral cancer. 1858 81


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