Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.16.3.1 (ceruloplasmin)
 5,074 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxidized copper wire, commonly referred to as copper oxide needles (CuON), was evaluated using purebred Hereford cows and their calves. Thirty-seven cows were allocated to Cu treatments of 0, 25 or 50 g CuON (79.9% Cu in CuON) with 12, 12 and 13 cows per treatment, respectively; calves within cow treatments were allocated to treatment of 0 and 20 g CuON. Single oral doses of CuON were given at the start of a grazing trial that lasted 92 d. Cows and calves were weighed and blood samples were taken on d 0, 28, 63 and 92; liver biopsies were taken on d 0, 28 and 92 of the grazing trial. Cattle were consuming grass forage with mean concentrations on d 0, 28, 63 and 92 of the grazing trial ranging from 1.6 to 5.5 mg/kg DM for Cu, 2.5 to 5.5 mg/kg DM for Mo and 1.3 to 1.5 g/kg DM for total S. The water consumed by cattle contained 947 mg sulfate per liter (SE = 13.2, n = 4). Body weight of cows and calves was not influenced (P greater than .05) by CuON. Liver Cu was higher (P less than .01) in treated cows and calves but was not different (P greater than .05) between cows dosed with 25 or 50 g CuON. Treatment of cows and calves with CuON had no influence (P greater than .05) on the concentration of Fe or Mo in liver or plasma, the concentration of Cu and ceruloplasmin activity in plasma, or the concentration of Zn in liver. Plasma Zn did not differ (P greater than .05) in cows, but it was higher (P less than .05) in the calves suckling cows treated with CuON. It was concluded that dosing cows and calves with CuON resulted in a higher Cu content of liver but did not adversely influence the metabolism of Fe or Zn or modify the concentration of Mo in the plasma or liver of cows or calves.
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PMID:Cupric oxide needles for grazing cattle consuming low-copper, high-molybdenum forage and high-sulfate water. 292 46

We have examined whether the toxic effects of homocysteine on cultured endothelial cells could result from the formation and action of hydrogen peroxide. In initial experiments with a cell-free system, micromolar amounts of copper were found to catalyze an oxygen-dependent oxidation of homocysteine. The molar ratio of homocysteine oxidized to oxygen consumed was approximately 4.0, which suggests that oxygen was reduced to water. The addition of catalase, however, decreased oxygen consumption by nearly one-half, which suggests that H2O2 was formed during the reaction. Confirming this hypothesis, H2O2 formation was detected using the horseradish peroxidase-dependent oxidation of fluorescent scopoletin. Ceruloplasmin was also found to catalyze oxidation of homocysteine and generation of H2O2 in molar amounts equivalent to copper sulfate. Finally, homocysteine oxidation was catalyzed by normal human serum in a concentration-dependent manner. Using cultured human and bovine endothelial cells, we found that homocysteine plus copper could lyse the cells in a dose-dependent manner, an effect that was completely prevented by catalase. Homocystine plus copper was not toxic to the cells. Specific injury to endothelial cells was seen only after 4 h of incubation with homocysteine plus copper. Confirming the biochemical studies, ceruloplasmin was also found to be equivalent to Cu++ in its ability to cause injury to endothelial cells in the presence of homocysteine. Since elevated levels of homocysteine have been implicated in premature development of atherosclerosis, these findings may be relevant to the mechanism of some types of chronic vascular injury.
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PMID:Endothelial cell injury due to copper-catalyzed hydrogen peroxide generation from homocysteine. 351 79

Protein and lipid analyses were conducted on isolated erythrocyte and lymphocyte plasma membranes from 7-wk-old male C57BL copper-deficient and copper-supplemented mice to investigate mechanisms for the altered immunity that accompanies dietary copper deficiency. Beginning at parturition, dams were fed a diet low in copper (0.5 mg/kg) and the offspring were weaned to this diet. Half the dams and their respective offspring received supplemental copper (20 mg/L) in the drinking water (+Cu) and served as controls. Unsupplemented offspring (-Cu) had lower activity of cuproenzymes serum ceruloplasmin, spleen and thymus cytochrome-c oxidase and copper, zinc-superoxide dismutase. The -Cu mice exhibited anemia, splenomegaly and thymic atrophy. Based on the marker enzyme alkaline phosphodiesterase I (APDE-I), lymphocyte plasma membranes were enriched 7- to 10-fold for spleen and thymus, respectively, after discontinuous sucrose density centrifugation. The activity of APDE-I was higher in spleen and thymus samples from -Cu mice than from those of +Cu mice for both crude homogenates and purified plasma membranes. Proteins were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by silver staining. A yellow-appearing band, Mr 74,000, present in all splenic membrane samples from +Cu mice was not evident in the samples from -Cu mice. Fatty acid methyl esters (FAME) were quantified by gas chromatography. Compared to splenic membranes from +Cu mice, the samples from -Cu mice demonstrated significant changes in all FAME (lower 16:0, 18:0 and 20:3n-6 and higher 18:1n-9, 18:2n-6 and 20:4n-6), including a higher unsaturation index. FAME composition of erythrocyte ghosts from -Cu mice demonstrated similar changes.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Dietary copper deficiency alters protein and lipid composition of murine lymphocyte plasma membranes. 359 18

Experiments were conducted to study the total lipid and fatty acid composition of liver, kidney, brain and heart of 7-wk-old male C57BL mice. Dietary copper deficiency was initiated at birth by feeding dams a purified diet containing 0.5 mg/kg copper. Offspring were fed the copper-deficient diet 4 wk postweaning. Control dams and offspring were fed the same diet but with added copper in the drinking water, 20 mg/L. Compared with controls the copper-deficient mice exhibited hepatomegaly, cardiac hypertrophy and a 4% reduction in brain weight as well as low ceruloplasmin activity (0.5% of control). Total phospholipid concentration in liver and kidney and total triacylglycerol concentration in kidney was lower in copper-deficient mice compared to concentrations measured in liver and kidney of control mice. The major change in essential fatty acid composition in the copper-deficient mice which was consistent between organs and lipid classes was a significantly lower proportion and absolute amount of dihomo-gamma-linolenic acid. Other changes in fatty acid composition were variable.
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PMID:Lipid and fatty acid composition of organs from copper-deficient mice. 374 62

Samples of human Fe.transferrin (Fe.HTr) were prepared from a single batch of apotransferrin (apo.HTr) by either the Fe(III)-citrate or the Fe(II)-ceruloplasmin (ferroxidase) method. By using 55Fe, 55Fe.HTr prepared by the citrate method and 55Fe.HTr prepared by the ceruloplasmin method contained 2.2-2.3 and 2.0 Fe/mol, respectively. For both 55Fe.HTr preparations, the isotope was shown to be associated with the protein from the measurement of absorbance at 465 nm and dialysis studies. However, passage of the 55Fe.HTr (ceruloplasmin) reaction mixture through DEAE-cellulose caused 55-60% of 55Fe to be lost from the protein, although no decrease in absorbance at 465 nm was observed. Ion-exchange chromatography of 55Fe.HTr (citrate) did not induce loss of 55Fe. Absorbance measurements showed significant differences between the two Fe.HTr preparations with respect to the ratios A212/A278 and A463/A278. Using an excitation wavelength of 275 nm, the fluorescence intensity ratios relative to apo.HTr were 0.275 and 0.309 for Fe.HTr (citrate) and Fe.HTr (ceruloplasmin), respectively. Electron spin resonance (ESR) measurements confirmed that Fe.HTr (citrate) and Fe.HTr (ceruloplasmin) were saturated with Fe. Hyperfine coupling constants and other features of the resonance profile revealed distinct differences between the two Fe.HTr preparations. Dialysis against H2O caused Fe.HTr (citrate), but not Fe.HTr (ceruloplasmin), to lose absorbance at 465 nm. The ESR profile of Fe.HTr (citrate), after dialysis against H2O, was reduced to multiple splittings and a lack of resolution of the central hyperfine structure. Addition of Na2CO3 restored the absorbance (465 nm) and the ESR pattern of Fe.HTr (citrate). In contrast, these properties of Fe.HTr (ceruloplasmin) were little affected by dialysis against H2O. However, the addition of trisodium citrate to Fe.HTr (ceruloplasmin) caused a reduction in absorbance at 465 nm and a change in ESR profile to resemble that of Fe.HTr (citrate) after dialysis in H2O; these changes, caused by citrate binding to Fe.HTr (ceruloplasmin), were restored to normal by the addition of Na2CO3. The data indicate that different protein conformations result from complexing Fe(III) with apo.HTr by these two different procedures. The two Fe.HTr products may differ, conceivably, in their abilities to transfer Fe to cells.
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PMID:A comparison of two procedures used for complexing Fe(III) with human apotransferrin: I. Physicochemical properties of the Fe(III) . transferrin products. 377 66

The effects of lead ingestion on parameters indicative of copper status, and particularly on the activity of the copper-dependent metalloenzyme superoxide dismutase (SOD) in erythrocytes, were investigated in weanling and neonatal rats. In a series of experiments, Sprague-Dawley or Long-Evans rats were fed a nutritionally adequate purified diet (AIN-'76). Lead acetate was given orally in the drinking water (0, 100, 250, or 500 ppm Pb) to groups of 23 to 26-day-old rats for 5 weeks or intragastrically (0, 5, 11, 22, or 45 mg Pb/kg body wt/day) to pups from postnatal Days 2 through 20. Lead ingestion (250 and 500 ppm Pb) by weanling rats resulted in decreased concentrations of copper in blood (erythrocytes and serum), liver, and spleen, in increased concentrations of iron in liver and spleen, in increased spleen weight, and in a small decrease in hemoglobin and hematocrit values. There was a significant decrease in the activities of the copper metalloproteins erythrocyte superoxide dismutase (SOD) and serum ceruloplasmin (Cp). In contrast, in the neonate we found no significant effects of lead on copper concentrations in blood or tissue or on other measures indicative of copper status. Despite high blood lead concentrations (1-3 micrograms/ml), SOD activity was not decreased in the neonatal rat. In addition, lead had no direct effect in vitro on the activity of bovine blood superoxide dismutase. On the basis of both the in vitro and in vivo studies, it appears likely that the observed decrease in SOD in young rats is caused indirectly by a lead-induced copper deficiency rather than by a direct inhibitory effect of lead.
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PMID:Erythrocyte superoxide dismutase activity and other parameters of copper status in rats ingesting lead acetate. 395 34

Cadmium chloride was administered in drinking water at a concentration of 50 ppm cadmium to female rats for 20 days of gestation. The foetuses were then removed from the uteri of the dams. Gestational exposure to oral cadmium resulted in decreased zinc, copper, iron, metallothionein, and thionein-bound zinc content in foetal liver as well as in reduced copper content in placenta and foetal intestine, brain and kidney. Subcellular fractionation of the foetal liver revealed decreased nuclear and cytoplasmic zinc content as well as decreased microsomal iron content. Pregnant rats exposed to oral cadmium revealed decreased serum zinc and iron concentration as well as reduced ceruloplasmin activity. The decreased zinc, copper, and iron content in foetal organs is suggested to be causally connected with the diminished availability of these metals in the maternal circulation.
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PMID:Effect of oral cadmium administration to female rats during pregnancy on zinc, copper, and iron content in placenta, foetal liver, kidney, intestine, and brain. 399 9

The kinetics of thermal denaturation of ceruloplasmin in water and in water with different percentage of D2O in the temperature range 25-85 degrees C, following the optical density change of the 610 nm charge transfer band of the protein has been investigated. A temperature Tt approximately equal to 65 degrees C above which an irreversible denaturation process of the protein active site takes place has been found. The kinetics of the denaturation process of the protein are fitted by two first order reactions, which have been assigned to a different thermal denaturation behaviour of the two Cu2+ type I sites existing in the protein. Addition of D2O to the protein solution affects the two kinetics in a different way, i.e. the rate of one of them is increased whilst that of the other is decreased. The different effect of D2O on the kinetics of disruption of the two copper sites is discussed in terms of different location and degree of hydrophobicity of the two Cu2+ type I sites.
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PMID:Isotopic effect on the kinetic of thermal denaturation of ceruloplasmin. 405 27

A comprehensive survey of the interaction of the copper proteins and oxygen is presented including a correlation of structure, function, and other properties of the known copper oxidases and of hemocyanin. The origin of their blue color and the structure of copper complexes and copper proteins are related to the oxidation state of copper ion and relevant electronic transitions probably arising from the formation of charge transfer complexes. The oxygen reactions of hemocyanin, ceruloplasmin, and cytochrome oxidase show half-saturation values far below the other Cu enzymes. The formation of hydrogen peroxide as a reaction product is associated with the presence of one Cu atom per oxidase molecule or catalytic system. Water is the corresponding product of the other Cu oxidases with four or more Cu atoms per molecule, except for monoamine oxidase. Mechanisms for the oxidase action of the two and four electron transfer Cu oxidases and tyrosinase are proposed. These reactions account for the number, the oxidation-reduction potential, and the oxidation state of Cu in the resting enzyme, the cyclical change from Cu(II) to Cu(I), the diatomic nature of O(2), the sequence of the oxidation and reduction reactions, and other salient features. The catalytic reactions involved in the oxidation of ascorbic acid by plant ascorbate oxidase, ceruloplasmin, and Cu(II) are compared. Finally the substrate specificity, inhibitory control, and the detailed mechanism of the oxidase activity of ceruloplasmin are summarized.
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PMID:Copper proteins and oxygen. Correlations between structure and function of the copper oxidases. 428 28

Male ICR mice were either given water containing Cd at a level of 192-200 ppm for 45 days (ingestion group), or were injected subcutaneously once a week with Cd (1 mg/kg) as CdCl2 for 7 weeks (injection group). The control group was given Cd-free water. In both Cd groups, the hematocrit and hemoglobin values did not change markedly. In the ingestion group, the Fe concentration decreased greatly in the liver, kidney, spleen, and duodenum. These decreases may be due to depression of Fe absorption from the intestine. In the injection group, Fe increased in the liver, spleen, and duodenum, although it decreased in the kidney. By Sephadex G-200 gel filtration, Fe-proteins in the hepatic supernatants were located in the void volume region of this gel column in both Cd groups. Apparently, Fe was not a component of metallothionein (MT) protein. The hepatic MT induction by Cd resulted in an increase in hepatic supernatant Cu. Serum Cu and ceruloplasmin (Cp) activity were stimulated only in the injection group. The enhancement of Cp activity may possibly be due to the increase in hepatic Cu which was accompanied by an increase in hepatic Fe, rather than a decrease. Our observations suggest that Fe metabolism is influenced differentially by the administration route of Cd.
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PMID:Effects of subcutaneous and oral cadmium on iron metabolism: role of ceruloplasmin and metallothionein. 651 7


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