Comparisons of copper deficiency states in the murine mutants blotchy and brindled. Changes in copper-dependent enzyme activity in 13-day-old mice.

The activity of two copper-dependent enzymes, cytochrome c oxidase and copper, zinc-superoxide dismutase, was determined in six tissues of age-matched (13-day-old) copper-deficient mutant and normal mice. In the two mutants 'brindled' and 'blotchy', brain, heart and skeletal muscle had significant enzyme deficiencies. Cytochrome c oxidase was more severely affected than was superoxide dismutase. In these three tissues the degree of deficiency could be correlated with decreased copper concentration; however, enzyme activity was normal in liver, kidney and lung, despite abnormal copper concentrations in these tissues. In nutritionally copper-deficient mice, all six tissues showed decreased enzyme activity, which was most marked in brain, heart and skeletal muscle, the tissues which showed enzyme deficiencies in the mutants. Analysis in vitro of cytochrome c oxidase (temperature coefficient = 2) at a single temperature was found to underestimate the deficiency of this enzyme in hypothermic copper-deficient animals. Cytochrome c oxidase deficiency may therefore be sufficiently severe in vivo to account for the clinical manifestations of copper deficiency. An injection of copper (50 micrograms of Cu+) at 7 days increased cytochrome c oxidase activity by 13 days in all deficient tissues of brindled mice, and in brain and heart from blotchy mice. However, skeletal-muscle cytochrome c oxidase in blotchy mutants did not respond to copper injection. Cytochrome c oxidase activity increased to normal in all tissues of nutritionally copper-deficient mice after copper injection, except in the liver. Hepatic enzyme activity remained severely deficient despite a liver copper concentration three times that found in copper-replete controls. Superoxide dismutase activity did not increase with treatment in either mutant, but its activity was higher than control levels in nutritionally deficient mice after injection. This difference is probably due to sequestration of copper in mutant tissue such as kidney, but a defect in the copper transport pathway to superoxide dismutase cannot be excluded.     

Copper-deficient rat embryos are characterized by low superoxide dismutase activity and elevated superoxide anions

The teratogenicity of copper (Cu) deficiency may result from increased oxidative stress and oxidative damage. Dams were fed either control (8.0 microg Cu/g) or Cu-deficient (0.5 microg Cu/g) diets. Embryos were collected on Gestational Day 12 for in vivo studies or on Gestational Day 10 and cultured for 48 h in Cu-deficient or Cu-adequate media for in vitro studies. Superoxide dismutase (SOD), glutathione peroxidase (GPX), and glutathione reductase (GR) activities were measured in control and Cu-deficient embryos as markers of the oxidant defense system. Superoxide anions were measured as an index of exposure to reactive oxygen species (ROS). No differences were found in GPX or GR activities among treatment groups. However, SOD activity was lower and superoxide anion concentrations higher in Cu-deficient embryos cultured in Cu-deficient serum compared to control embryos cultured in control serum. Even so, Cu-deficient embryos had similar CuZnSOD protein levels as controls. In the in vitro system, Cu-deficient embryos had a higher frequency of malformations and increased staining for superoxide anions in the forebrain, heart, forelimb, and somites compared to controls. When assessed for lipid and DNA oxidative damage, conjugated diene concentrations were similar among the groups, but a tendency was observed for Cu-deficient embryos to have higher 8-hydroxy-2'-deoxyguanosine concentrations than controls. Thus, Cu deficiency resulted in embryos with malformations and reduced SOD enzyme activity. Increased ROS concentrations in the Cu-deficient embryo may cause oxidative damage and contribute to the occurrence of developmental defects.     

Effects of dietary carbohydrate intake on antioxidant enzyme activity and copper status in the copper-deficient streptozotocin (STZ) diabetic rat

The aim of this study was to investigate how dietary lactose, compared with sucrose, in association with copper deficiency influences the antioxidant and copper status in the diabetic rat. Two groups of male rats (n = 12) were fed copper-deficient diets containing either 300 g/kg of sucrose or 300 g/kg of lactose in a pair-feeding regime for 35 days. Six rats from each group were injected with streptozotocin to induce diabetes. After a further 16 days the animals were killed and the liver, heart, and kidney removed for the measurement of copper levels and the activities of antioxidant and related enzymes. Diabetes resulted in higher hepatic and renal copper levels compared with controls. The copper content of the heart and kidney in diabetic rats consuming sucrose was also significantly higher than in those consuming lactose. Catalase activity in the liver, heart, and kidney was significantly increased in diabetic rats compared with controls. Hepatic glutathione S-transferase and glucose-6-phosphate dehydrogenase and cardiac copper zinc superoxide dismutase activities were also higher in diabetes. Sucrose, compared with lactose feeding, resulted in higher cytochrome c oxidase and glutathione peroxidase activities in the kidney while glucose-6-phosphate dehydrogenase activity was lower. The combination of lactose feeding and diabetes resulted in significantly higher activities of cardiac managanese superoxide dismutase and catalase and renal manganese superoxide dismutase and glucose-6-phosphate dehydrogenase. These results suggest that sucrose consumption compared with lactose appears to be associated with increased organ copper content and in general decreased antioxidant enzyme activities in copper-deficient diabetic rats.     

Neuronal NOS-mediated nitration and inactivation of manganese superoxide dismutase in brain after experimental and human brain injury

Manganese superoxide dismutase (MnSOD) provides the first line of defense against superoxide generated in mitochondria. SOD competes with nitric oxide for reaction with superoxide and prevents generation of peroxynitrite, a potent oxidant that can modify proteins to form 3-nitrotyrosine. Thus, sufficient amounts of catalytically competent MnSOD are required to prevent mitochondrial damage. Increased nitrotyrosine immunoreactivity has been reported after traumatic brain injury (TBI); however, the specific protein targets containing modified tyrosine residues and functional consequence of this modification have not been identified. In this study, we show that MnSOD is a target of tyrosine nitration that is associated with a decrease in its enzymatic activity after TBI in mice. Similar findings were obtained in temporal lobe cortical samples obtained from TBI cases versus control patients who died of causes not related to CNS trauma. Increased nitrotyrosine immunoreactivity was detected at 2 h and 24 h versus 72 h after experimental TBI and co-localized with the neuronal marker NeuN. Inhibition and/or genetic deficiency of neuronal nitric oxide synthase (nNOS) but not endothelial nitric oxide synthase (eNOS) attenuated MnSOD nitration after TBI. At 24 h after TBI, there was predominantly polymorphonuclear leukocytes accumulation in mouse brain whereas macrophages were the predominant inflammatory cell type at 72 h after injury. However, a selective inhibitor or genetic deficiency of inducible nitric oxide synthase (iNOS) failed to affect MnSOD nitration. Nitration of MnSOD is a likely consequence of peroxynitrite within the intracellular milieu of neurons after TBI. Nitration and inactivation of MnSOD could lead to self-amplification of oxidative stress in the brain progressively enhancing peroxynitrite production and secondary damage.     

Quantitative assessment of tyrosine nitration of manganese superoxide dismutase in angiotensin II-infused rat kidney

Hypertension caused by angiotensin II is characterized by an increase in tissue oxidant stress as evidenced by increased quantities of reactive oxygen and nitrogen species. Manganese superoxide dismutase (MnSOD) is a key mitochondrial antioxidant enzyme that is inactivated in conditions of oxidant stress by reacting with peroxynitrite to form 3-nitrotyrosine in its active site. The increase in 3-nitrotyrosine content in MnSOD in the kidney of angiotensin II-infused rats was assessed in this study by immunohistochemistry, Western blotting, immunoprecipitation, and HPLC with UV detection (HPLC-UV). MnSOD activity decreased approximately 50% in angiotensin II-infused rat kidneys (24 +/- 4.6 vs. 11 +/- 5.2 U/mg) without a change in protein expression. Immunohistochemical staining showed 3-nitrotyrosine predominantly in distal tubules and collecting duct cells in the angiotensin II-infused rat kidneys. By two-photon microscopy, 3-nitrotyrosine colocalized with MnSOD. Total 3-nitrotyrosine content in kidney homogenates was increased in angiotensin II-infused rat kidney [3.2 +/- 1.9 (sham treated) vs. 9.5 +/- 2.3 ng/mg protein by HPLC-UV detection]. With tracer amounts of tyrosine-nitrated recombinant MnSOD, the most sensitive technique to detect tyrosine nitration of MnSOD was immunoprecipitation from tissue with anti-MnSOD antibody, followed by detection of 3-nitrotyrosine by Western blotting or HPLC. By HPLC, 3-nitrotyrosine content of kidney MnSOD increased 13-fold after angiotensin II infusion, representing an increase from approximately one-twentieth to one-fifth of the total 3-nitrotyrosine content in sham-treated and angiotensin II-infused rat kidney, respectively. Angiotensin II-induced hypertension is accompanied by increased tyrosine nitration of MnSOD, which, because it inactivates the enzyme, may contribute to increased oxidant stress in the kidney.     

Variable response of selected cuproproteins in rat choroid plexus and cerebellum following perinatal copper deficiency

Recent immunohistochemical characterization of the copper transport protein, Ctr1, reported enriched levels in mouse choroid plexus, and enhancement by copper deficiency. To extend and confirm this, experiments were conducted with Holtzman rats. Following perinatal copper deficiency there was an 80% reduction in brain copper of 24-27 day old copper-deficient (Cu-) rat pups compared to copper-adequate (Cu+) controls. Choroid plexus immunoblot analysis with rabbit anti-hCtr1 demonstrated a 50% higher Ctr1 protein expression in Cu-samples. However, levels of copper chaperone for superoxide dismutase (CCS) were unchanged, suggesting that Ctr1 buffers the choroid plexus against copper deficiency, since CCS normally is much higher in Cu-tissues. There were 13% lower levels of cytochrome c oxidase subunit IV (COX IV) detected in Cuchoroid plexus. In contrast, in cerebellum of Cu-rats CCS was 2-fold higher and COXIV 1.7-fold lower than Cu+ rats consistent with severe copper deficiency. Brain mitochondria from Cu-rats had severe reductions in COXIV content and CCO activity and modest but significant elevations in CCS and reductions in Cu, Zn-superoxide dismutase. COXIV may be a more sensitive marker for copper deficiency than CCS and may prove useful to assess copper status.     

Effects of dietary tin and copper on rat hepatocellular antioxidant protection

The effects of dietary tin on copper status and on enzymes and metabolites involved in hepatocellular antioxidant protection were measured in rats fed copper-adequate or copper-deficient diets with glucose or fructose. Rats became copper-depleted after 4 weeks on diets containing less than 0.5 micrograms of copper/g as evidenced by significant decreases in liver copper and serum ceruloplasmin. Signs of copper deficiency occurred in copper-depleted rats fed diets containing 100 micrograms of tin/g. Significant effects of tin on liver glutathione peroxidase and superoxide dismutase activities and on liver iron and total glutathione concentrations were observed. Interactions between copper and tin on liver copper and iron and on liver superoxide dismutase and malondialdehyde production are reported. Adverse effects of feeding diets containing 100 micrograms of tin/g include (i) copper depletion in rats fed copper-adequate diets, (ii) accelerated development of copper deficiency in rats fed copper-deficient diets, and (iii) reduction in hepatocellular antioxidant protection.     

Weak antioxidant defenses make the heart a target for damage in copper-deficient rats

Copper deficiency causes more salient pathologic changes in the heart than in the liver of rats. Although oxidative stress has been implicated in copper deficiency-induced pathogenesis, little is known about the selective toxicity to the heart. Therefore, we examined the relationship between the severity of copper deficiency-induced oxidative damage and the capacity of antioxidant defense in heart and liver to investigate a possible mechanism for the selective cardiotoxicity. Weanling rats were fed a purified diet deficient in copper (0.4 μg/g diet) or one containing adequate copper (6.0 μg/g diet) for 4 weeks. Copper deficiency induced a 2-fold increase in lipid peroxidation in the heart (thiobarbituric assay) but did not alter peroxidation in the liver. The antioxidant enzymatic activities of superoxide dismutase, catalase, and glutathione peroxidase were, respectively, 3-, 50- and 1.5-fold lower in the heart than in the liver, although these enzymatic activities were depressed in both organs by copper deficiency. In addition, the activity of glutathione reductase was 4 times lower in the heart than in the liver. The data suggest that a weak antioxidant defense system in the heart is responsible for the relatively high degree of oxidative damage in copper-deficient hearts.     

Development of copper deficiency in rats fed fructose or starch: weekly measurements of copper indices in blood

Copper deficiency was induced in weanling rats fed diets whose sole source of carbohydrates was starch or fructose for 7 weeks. Conventional parameters of copper status, plasma copper concentrations, ceruloplasmin activity, and erythrocyte superoxide dismutase (SOD) activity were longitudinally monitored weekly to follow the development of the deficiency and to correlate these indices with the degree of severity of the deficiency. Although 30% of the rats fed a copper-deficient fructose diet died and no deaths occurred in rats fed the copper-deficient starch diet, plasma copper, ceruloplasmin, and SOD activities were reduced to a similar extent in all rats fed copper-deficient diets regardless of the type of dietary carbohydrate. Thus, none of the indices used accurately reflected the greater degree of deficiency or mortality in rats fed the fructose diet deficient in copper. The results of the present study underscore the need for more sensitive tests or alternative parameters to assess copper status in living animals.     

COPPER DEFICIENCY IN THE DEVELOPING RAT BRAIN: A POSSIBLE MODEL FOR MENKES'' STEELY-HAIR DISEASE

Abstract— In comparison to controls, copper-deficient suckling rats showed an appreciable decrease in body growth, a slight decrease in whole brain and cerebellar growth, and a highly significant decrease in myelination based on the activity of cerebellar 2',3'-cyclic nucleotide 3'-phosphohydrolase—a myelin enriched protein. Specific effects of a fivefold reduction in the copper content of brain were seen in a drastic decrease in cerebellar cytochrome c oxidase and smaller but significant drops in cerebellar super-oxide dismutase and brain norepinephrine concn. These observations are discussed with respect to the neuropathology and biochemistry of Menkes' steely-hair disease, a sex-linked recessive disorder in humans characterized by copper deficiency.     

Comparison of copper status in rats when dietary fructose is replaced by either cornstarch or glucose

The purpose of this study was to determine what levels of starch or glucose replacement for fructose in the copper-deficient diet (copper) can minimize the fructose-copper interaction. Experimental diets contained either 100% fructose as the carbohydrate source, or the fructose was partially replaced with 50% starch, 50% glucose, 75% starch, or 75% glucose. Diets were either copper adequate (7-8 ppm) or inadequate (less than 1 ppm). Male weanling rats were fed their respective diet for 5 weeks and then fasted overnight. After decapitation, blood was collected and liver and heart were removed. Plasma copper was significantly reduced and ceruloplasmin was not detected in all copper-deficient groups. Copper deficiency increased plasma cholesterol, as well as heart and liver weight in the glucose groups, but not in the starch groups. Those organ weights were heavier in glucose-copper than starch-copper rats. Erythrocyte copper-zinc-superoxide dismutase activity was greater in starch-copper rats. Erythrocyte copper-zinc-superoxide dismutase activity was greater in starch-copper than glucose-copper rats regardless of carbohydrate amount. Hepatic copper concentration of the group fed starch-copper was twice levels observed in glucose-copper. The 50% glucose rats had lower hepatic copper than the 75% glucose rats. Hepatic copper-zinc-superoxide dismutase activity showed patterns similar to hepatic copper. Cardiac copper was greater in starch-copper than glucose-copper rats. Cardiac copper-zinc-superoxide dismutase activity was equally reduced in all copper-deficient groups. The 50% starch-replaced diet was more effective in minimizing copper deficiency than the 75% glucose-replaced diet. This poorer improvement of copper deficiency by glucose than starch may partially be due to a more severe reduction of food intake in glucose than in starch diets.     

Effect of copper deficiency on oxidative DNA damage in Jurkat T-lymphocytes

The micronutrient copper is a catalytic cofactor for copper, zinc superoxide dismutase and ceruloplasmin, which are two important antioxidant enzymes. As such, a lack of copper may promote oxidative stress and damage. The purpose of this study was to determine the effect of copper deficiency on oxidative damage to DNA in Jurkat T-lymphocytes. To induce copper deficiency, cells were incubated for 48 h with 5-20 microM 2,3,2-tetraamine (2,3,2-tet), a high affinity copper chelator. Such treatment did not affect cell proliferation/viability, as assessed by measuring mitochondrial reduction of WST-1 reagent (4-[3-(4-Iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-ben zen e disulfonate). Furthermore, the induction of copper deficiency did not promote oxidative DNA damage as evaluated by the comet assay. Comet scores were 15 +/- 0 and 16 +/- 1 for control and copper-deficient cells, respectively. However, the copper-deficient cells sustained greater oxidative DNA damage than the control cells (comet scores of 175 +/- 15 and 50 +/- 10, respectively) when both were oxidatively challenged with 50 microM hydrogen peroxide (H(2)O(2)). Supplemental copper but not zinc or iron prevented the potentiation of the H(2)O(2)-induced oxidative DNA damage caused by 2,3,2-tet. These data suggest that copper deficiency compromises the antioxidant defense system of cells, thereby increasing their susceptibility to oxidative DNA damage.     

Copper modulates the degradation of copper chaperone for Cu,Zn superoxide dismutase by the 26 S proteosome

Copper chaperones are copper-binding proteins that directly insert copper into specific targets, preventing the accumulation of free copper ions that can be toxic to the cell. Despite considerable advances in the understanding of copper transfer from copper chaperones to their target, to date, there is no information regarding how the activity of these proteins is regulated in higher eukaryotes. The insertion of copper into the antioxidant enzyme Cu,Zn superoxide dismutase (SOD1) depends on the copper chaperone for SOD1 (CCS). We have recently reported that CCS protein is increased in tissues of rats fed copper-deficient diets suggesting that copper may regulate CCS expression. Here we show that whereas copper deficiency increased CCS protein in rats, mRNA level was unaffected. Rodent and human cell lines cultured in the presence of the specific copper chelator 2,3,2-tetraamine displayed a dose-dependent increase in CCS protein that could be reversed with the addition of copper but not iron or zinc to the cells. Switching cells from copper-deficient to copper-rich medium promoted the rapid degradation of CCS, which could be blocked by the proteosome inhibitors MG132 and lactacystin but not a cysteine protease inhibitor or inhibitors of the lysosomal degradation pathway. In addition, CCS degradation was slower in copper-deficient cells than in cells cultured in copper-rich medium. Together, these data show that copper regulates CCS expression by modulating its degradation by the 26 S proteosome and suggest a novel role for CCS in prioritizing the utilization of copper when it is scarce.     

Intracellular copper deficiency increases amyloid-beta secretion by diverse mechanisms

In Alzheimer's disease there is abnormal brain copper distribution, with accumulation of copper in amyloid plaques and a deficiency of copper in neighbouring cells. Excess copper inhibits Abeta (amyloid beta-peptide) production, but the effects of deficiency have not yet been determined. We therefore studied the effects of modulating intracellular copper levels on the processing of APP (amyloid precursor protein) and the production of Abeta. Human fibroblasts genetically disposed to copper accumulation secreted higher levels of sAPP (soluble APP ectodomain)alpha into their medium, whereas fibroblasts genetically manipulated to be profoundly copper deficient secreted predominantly sAPPbeta and produced more amyloidogenic beta-cleaved APP C-termini (C99). The level of Abeta secreted from copper-deficient fibroblasts was however regulated and limited by alpha-secretase cleavage. APP can be processed by both alpha- and beta-secretase, as copper-deficient fibroblasts secreted sAPPbeta exclusively, but produced primarily alpha-cleaved APP C-terminal fragments (C83). Copper deficiency also markedly reduced the steady-state level of APP mRNA whereas the APP protein level remained constant, indicating that copper deficiency may accelerate APP translation. Copper deficiency in human neuroblastoma cells significantly increased the level of Abeta secretion, but did not affect the cleavage of APP. Therefore copper deficiency markedly alters APP metabolism and can elevate Abeta secretion by either influencing APP cleavage or by inhibiting its degradation, with the mechanism dependent on cell type. Overall our results suggest that correcting brain copper imbalance represents a relevant therapeutic target for Alzheimer's disease.     

Effect of nutritional copper deficiency on carrageenin edema in the rat

The effects of nutritional copper deficiency on carrageenin edema in the rat were investigated with emphasis on studying the correlation between the degree of copper deficiency and the degree of edema. Carrageenin paw edema in both copper-sufficient and copper-deficient groups of rats was compared after either 20, 40, or 60 d on respective diets. The degree of copper deficiency was quantitated by analyzing total copper concentrations in a number of tissues. Other copper dependent parameters were also determined. Results indicated that: (1) although copper sufficient rats showed relatively little change in the degree of edema, copper-deficient rats showed a steady and significant increase in edema from d 20 to 40 to 60; (2) paw edema in copper-deficient animals was highly and negatively correlated to the concentrations of copper in the liver; the correlation with liver Cu,Zn-superoxide dismutase activity, however, was inconsistent; (3) paw edema was not correlated either to copper concentration in tissues other than liver or to plasma ceruloplasmin activity; and (4) aggravation of carrageenin edema in copper-deficient animals seemed to be mediated via an as yet unknown secondary effect of copper deficiency.     

Interaction Between Dietary Carbohydrate and Copper Nutriture on Lipid Peroxidation in Rat Tissues

The effects of the interactions between dietary carbohydrates and copper deficiency on superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and their roles in peroxidative pathways were investigated. Weanling rats were fed diets deficient in copper and containing either 62% starch, fructose, or glucose. Decreased activity of SOD was noted in all rats fed the copper-deficient diets regardless of the nature of dietary carbohydrate. However, the decreased activity was more pronouced in rats fed fructose. Feeding the fructose diets decreased the activity of GSH-Px by 25 and 50% in the copper-supplemented and copper-deficient rats, respectively, compared to enzyme activities in rats fed similar diets containing either starch or glucose. The decreased SOD and GSH-Px activities in rats fed the fructose diet deficient in copper were associated with increased tissue per-oxidation and decreased hepatic adenosine triphosphate (ATP). When the fructose in the diet of copper-deficient rats was replaced with either starch or glucose, tissue SOD and GSH-Px activities were increased and these increases in enzyme activity were associated with a tendency toward reduced mitochondrial peroxidation when compared to the corre-sponding values for rats fed fructose throughout the experiment Dietary fructose aggrevated the symptoms associated with copper deficiency, but starch or glucose ameliorated them. The protective effects were more pronounced with starch than with glucose.     

Purification of a fully metal-depleted Cu, Zn superoxide dismutase from copper-deficient rat liver

A copper-deprived form of the enzyme Cu, Zn superoxide dismutase was identifiedin the liver of rats made copper-deficient by dietary restriction. In homogenates ofsuch livers Cu, Zn superoxide dismutase presents a dis-homogeneous electrophoreticprofile with respect to the native enzyme. When rat liver extracts were treated withexogenous copper an electrophoretic pattern resembling the native one was observed.Enzyme purified by chromatography on DE-52 resin shows two major components, onecorresponding to genuine, native enzyme and another one, eluting at higher ionicstrength. The latter protein (Fraction II) consists of several isoforms which showthe same characteristics of the native superoxide dismutase as far as immunoreactivityand molecular weight are concerned, but with decreased contents of copper and zinc. Itscatalytic constant, referring to copper content, was 15 times lower than that obtainedfor the native enzyme. Moreover, the catalytic power of purified Fraction II was notregained upon incubation with copper. The occurrence of a superoxide dismutase voidof metals confirms the hypothesis that this protein plays a dual physiological role:in metal metabolism and in superoxide anion dismutation.     

Dietary carbohydrate influences tissue fatty acid and lipid composition in the copper-deficient rat

Fructose and copper have been shown independently to influence long chain fatty acid metabolism. Since fructose feeding exacerbates copper deficiency, their possible interaction with respect to tissue long chain fatty acid and lipid composition was studied. Weanling male Sprague-Dawley rats were given diets containing 0.6 or 6 mg/kg copper. The carbohydrate source (627 g/kg) was either fructose or corn starch. After 3 wk, fatty acid profiles and total lipids in heart and liver were analyzed. Copper-deficient rats fed fructose had more severe signs of copper deficiency than those fed starch, according to heart/body wt ratio, hematocrit, and liver copper content. The fatty acid composition of heart and liver triacylglycerol was significantly different between groups, but the changes did not correlate with the severity of copper deficiency. In heart, phosphatidylinositol and phosphatidylserine, arachidonic acid and docosapentaenoic acid (n-6) were increased 193 and 217%, respectively, p<0.05) in rats given the copper-deficient diet containing fructose. Changes in the long chain fatty acids in heart phospholipids may be related to the higher mortality commonly observed in rats fed a copper-deficient diet containing fructose.     

Nutritional copper deficiency does not affect sponge granuloma formation in the rat

Sponge granuloma formation was compared in copper-deficient and copper-sufficient rats following feeding of respective diets for 20, 40, or 60 d. Body weight, total blood hemoglobin, and activities of ceruloplasmin and Cu, Zn-superoxide dismutase in plasma were monitored to ascertain copper deficiency. Mean granuloma weights (mg +/- SEM) in copper-deficient and copper-sufficient groups of rats, respectively, were as follows: 37 +/- 2 and 38 +/- 2 after 20 d, 22 +/- 2 and 23 +/- 2 after 40 d, and 19 +/- 1 and 21 +/- 1 after 60 d on respective diets. Thus, nutritional copper deficiency did not have an effect on sponge granuloma formation in the rat.