Cu In Serum Research Articles

Copper deficit as a potential pathogenic factor of reduced bone mineral density and severe tooth wear

SummaryThe study evaluated if men and women with severe tooth wear were at increased risk of general bone loss. Enamel biopsies obtained from 50 subjects aged 47.5 ± 5 years showed decreased copper content, which was associated with reduced spine bone mineral density, suggesting deficits of this trace element contributing to bone demineralization, enamel attrition, and deteriorated quality of mineralized tissues.IntroductionThe objective of this cross-sectional study was to assess associations between enamel trace minerals and bone mineral density (BMD) in severe tooth wear. We hypothesized that similar factors contributed to both the excessive abrasion of dental enamel and reduced BMD in subjects with tooth wear.MethodsFifty patients aged 47.5 ± 5 years with severe tooth wear and 20 age-, sex-, and body mass index (BMI)-matched healthy volunteers with normal dental status were studied regarding dietary intakes of trace elements, serum and salivary copper (Cu), zinc (Zn), and calcium (Ca) concentrations, and serum PTH, osteocalcin, and hydroxyvitamin D levels. Tooth wear was determined using clinical examination based on standard protocol according to Smith and Knight. In all subjects, acid biopsies of the maxillary central incisors were carried out to assess mineral composition of the enamel. Atomic absorption spectroscopy with an air/acetylene flame was used to measure Ca and Zn, and graphite furnace atomic absorption spectroscopy was used to analyze Cu content. BMD was examined using dual energy X-ray absorptiometry.ResultsTooth wear patients had reduced lumbar spine, but not femoral, BMD relative to controls (p < 0.001). No differences were found in enamel Ca concentration and Zn content was slightly higher in tooth wear patients than in controls whereas Cu content was significantly decreased in the patients: 19.59 ± 16.4 vs 36.86 ± 26.1 μg/l (p = 0.01) despite similar levels of Cu in serum and saliva. The differences were independent of serum 25-OH-D, osteocalcin concentrations or PTH either.ConclusionSevere tooth wear is associated with reduced spinal BMD. Enamel in adult individuals with severe tooth wear is low in copper content. Therefore, further work is needed to determine whether copper plays a role in bone pathophysiology in these patients.

Copper/zinc and copper/selenium ratios, and oxidative stress as biochemical markers in recurrent aphthous stomatitis

ProjectRecurrent aphthous stomatitis (RAS) is a common oral mucosal disorder characterized by recurrent, painful oral aphthae, and oxidative stress presumably contributes to its pathogenesis. The aim of this study is to scrutinize the relationship between oxidative stress and serum trace elements (copper, Cu; zinc, Zn; selenium, Se), and to evaluate the ratios of Cu/Zn and Cu/Se in this disorder. ProcedurePatients with RAS (n=33) and age- and sex-matched healthy control subjects (n=30) were enrolled in this study. Malondialdehyde (MDA) concentrations in plasma and the activities of superoxide dismutase (SOD1; CuZnSOD), glutathione peroxidase (GPx) and catalase (CAT) in erythrocyte were determined as spectrophotometric. Also, the levels of Se, Zn and Cu in serum were determined on flame and furnace atomic absorption spectrophotometer using Zeeman background correction. Results and conclusionsOxidative stress was confirmed by the significant elevation in plasma MDA, and by the significant decrease in CAT, SOD1, and GPx (p<0.05). When compared to controls, Zn and Se levels were significantly lower in patients, whereas Cu levels was higher in RAS patients than those in controls (p<0.05). In addition, the correlation results of this study were firstly shown that there were significant and positive correlations between Se–CAT, Se–GPx, and Cu–MDA parameters, but negative correlations between Se–Cu, Se–MDA, Cu–CAT, Cu–SOD1 and Cu–GPx parameters in RAS patients. Furthermore, the ratios of Cu/Zn and Cu/Se were significantly higher in the patients than the control subjects (p<0.05). Our results indicated that lipid peroxidation associated with the imbalance of the trace elements seems to play a crucial role in the pathogenesis of RAS. Furthermore, the serum Cu/Zn and Cu/Se ratios may be used as biochemical markers in these patients.

An evaluation of the effect of clotting on the recovery of copper from caprine blood

In the goat, diagnosis of copper (Cu) deficiency is often based on measurement of Cu in serum or plasma. Previous research in cattle and sheep has shown that these values are not interchangeable, but data for goats have not been published. Paired serum and heparinised plasma samples taken from 119 goats in eight herds were tested for Cu concentration. Plasma and serum Cu were significantly correlated (r=0.95). On average serum Cu was 3.5 μmol/L lower than plasma Cu, but this difference was related to Cu status (r=0.45). Mean serum Cu concentration was 83% of plasma Cu, with the 95% limits of agreement ranging from 66% to 100%. Similar to cattle and sheep, individual variability in Cu loss during clotting is too great for serum Cu to be used as a measure of Cu status in goats.

Possible subclinical hepatopathy after copper supplementation in farmed red deer

AIM: To determine the effect of parenteral supplementation with Cu on the activities of hepatic enzymes in deer with adequate concentration(s) of Cu in liver and serum. METHODS: Male red deer aged 12 months were given either 0.8 or 1.6 mg of Cu/kg of a S/C injectable Cu formulation or no Cu (n=10/group) on 03 December 2007 (Day 0). Concentration of Cu in liver was measured in biopsies taken on Days −13 and 17, and that in serum on Days 0, 1, 3 and 17. Liver enzymes, gamma-glutamyl transferase (GGT) and glutamate dehydrogenase (GDH), were measured in serum on Days 3 and 7. Deer were weighed on Days 0 and 17. RESULTS: The mean concentration of Cu in liver was 203 (range 50–460) μmol/kg fresh weight (FW) on Day −13 and that in serum was 14.8 (range 7.8–25.0) μmol/mL on Day 0. Concentrations of Cu in liver were adequate (>100 μmol/kg FW) in 25/30 deer. Injection with 0.8 mg of Cu/kg resulted in elevated mean concentrations of Cu in serum to 20.3 (range 14–26) and 17.4 (range 12–26) μmol/mL on Days 1 and 3 respectively, whereas 1.6 mg/kg resulted in mean concentrations of Cu in serum of 26.7 (range 20–42) and 19.3 (range 16–25) μmol/mL on Days 1 and 3 respectively (p<0.05). The mean concentration of Cu in liver on Day 17 was 1,460 (range 1,000–2,300) after injection with 0.8 mg/kg, 1,666 (range 1,100–2,200) after 1.6 mg/kg, and 280 (range 75–420) μmol/kg FW in controls. Injection with 1.6 mg Cu/kg, but not 0.8 mg/kg, resulted in an increase in the activity of GGT (p=0.05), and in 4/10 deer a marked change in the activity of GDH, between Day 3 and Day 7, indicating that injection of copper induced a moderate degree of subclinical hepatopathy. Mean liveweight gain (g/day) to Day 17 was 105.9 (range −176 to 411) in control animals and 64.7 (range −59 to 176) 64.7 and −61.7 (range −294 to 117) in deer given 0.8 and 1.6 mg/Cu/kg respectively (p=0.003). CONCLUSIONS: S/C administration of 1.6 mg of Cu/kg in deer which had adequate Cu status pre-treatment resulted in elevated activities of GGT and GDH in serum, indicating hepatopathy, and both this dose rate and 0.8 mg/kg resulted in reduced liveweight gain post-treatment compared with untreated controls. CLINICAL SIGNIFICANCE: Cu supplementation should not be administered when the Cu status of deer is adequate or unknown.

Determination of elements in kidney, serum and urine of Wistar rats with Acute Renal Insufficiency using NAA

In this investigation ions in serum, urine and kidney of Wistar rats (control group) and Wistar with Acute Renal Insufficiency (ARI) were quantified using instrumental neutron activation analysis. The measurements in serum and urine were performed before, during and after ischemia-induced ARI. The measurements in kidney were performed for the control and ARI groups. Also, a comparative analysis between the concentration ratios before, during and after ARI was performed in urine and serum samples for both groups. The variations results for Cu in serum and I in urine, before and after ischemia-induced ARI, suggest that these elements must be also investigated in renal dysfunction.

Effects of Ellagic Acid on Copper, Zinc, and Biochemical Values in Serum and Liver of Experimental Cholestatic Rats

Ellagic acid (EA) is a natural polyphenolic compound. Although, modulator effects of EA on copper (Cu) and zinc (Zn) levels in some liver diseases have been reported in experimental animals, its effects in obstructive jaundice (OJ) has not been clarified. We aimed to evaluate potential effects of EA on Cu and Zn levels in liver and serum of cholestatic rats. Forty Wistar albino rats were equally divided into four groups. First group was used as controls. Second group received EA (60 mg(-1) kg(-1) day(-1)) for 8 days. Third was OJ group, and fourth group was OJ plus EA group. After 8 days, blood and liver samples were obtained. Higher serum and liver Cu and lower serum and liver Zn levels were found in OJ group (p < 0.05) compared with other groups. However, these differences reached to significant levels for Cu in serum and for Zn in lever. Higher serum copper levels were decreased, and lower liver Zn levels were increased by EA treatment in cholestatic rats (p < 0.05). Also, higher Cu/Zn ratio in OJ group was decreased by EA treatment both in liver (p < 0.05) and in serum (p < 0.05). Significantly higher serum bilirubin, alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase values were found in OJ and OJ + EA groups compared with the control and EA groups (p < 0.05). In conclusion, result of the current study indicated that ellagic acid has modulator effects on Cu and Zn levels in liver and serum of cholestatic rats.

The impact of high zinc intake on the copper status of dairy cows in New Zealand

AIM: To determine the effect of a high Zn intake on the concentration of Cu in the liver of dairy cows. METHODS: Sixty non-pregnant, non-lactating, mixed-age Friesian dairy cows were randomised into four groups: unsupplemented control; thrice weekly oral treatment with 350 mg Cu (equivalent to 150 mg Cu/day) as CuSO4.5H2O; a ZnO bolus releasing 6.628 g Zn/day given on Days 0 and 28; and oral treatment with Cu and ZnO boluses. The cows were fed baled silage for the duration of the study (56 days). On Days -12, 14, 28, 42 and 56 liver biopsies were collected for determination of concentrations of Cu, and blood samples for measurement of Cu and Zn in serum. RESULTS: Mean concentrations of Cu in the liver of unsupplemented control cows decreased from an initial 717 (SE 108.5) to 396 (SE 88.0) µmol/kg fresh tissue on Day 28, and then increased to 542 (SE 105.3) µmol/kg fresh tissue on Day 42, before decreasing to 434 (SE 81.6) µmol/kg fresh tissue on Day 56. Administration of ZnO resulted in no change in the concentration of Cu in liver compared with controls. Supplementing with 150 mg Cu/day significantly increased the concentration of Cu in liver, compared with controls, to 1,074 (SE 105.2) µmol/kg fresh tissue on Day 56. Treatment with ZnO significantly reduced concentrations of Cu in liver on Day 56, compared with Cu-supplemented cows, to 786 (SE 107.7) µmol/kg fresh tissue. The treatments had no effect on concentrations of Cu in serum. In cows given the ZnO, mean concentrations of Zn in serum increased from 17 (SE 0.6) on Day 0 to 30 (SE 1.7) µmol/L on Day 14, then decreased to 20 (SE 1.3) µmol/L on Day 28, increased to 40 (SE 2.9) µmol/L on Day 42, then decreased to 24 (1.16) µmol/L on Day 56. In cows given ZnO plus Cu, concentrations of Zn in serum were significantly greater than in cows only given ZnO on Day 41 (46 (SE 2.71) vs 35 (SE 3.23) µmol/L, respectively). Mean concentrations of Cu, Mo and Zn in the baled silage were 4.4, 0.5 and 21 mg/kg dry matter (DM), respectively. CONCLUSIONS: High Zn intakes used in the prevention of facial eczema in dairy cows had little effect on concentrations of Cu in liver when the Cu intake was low, but decreased the efficacy of a Cu supplement by about 50%. CLINICAL RELEVANCE: When using Zn as a prophylactic treatment for facial eczema the level of Cu supplementation should be adjusted, which may mean that in some situations it is recommended not to supplement cows with Cu.

Accumulation and depletion of liver copper stores in dairy cows challenged with a Cu-deficient diet and oral and injectable forms of Cu supplementation

AIM: To quantify the capacity of the liver to respond to a Cudeficient diet and various forms of Cu supplementation in dairy cows with high Cu status. METHODS: Sixty non-pregnant, non lactating mixed-age Freisian dairy cows were fed baled silage for 116 days, containing 5.8 mg Cu/kg dry matter (DM), that provided an inadequate Cu intake. They were either unsupplemented (Control); or treated thrice weekly orally with solutions containing the equivalent of 150 mg Cu/day as copper sulphate pentahydrate (CS), copper amino chelate (CAC), or copper glycinate (CG); 16 g Cu as Cu0 wire particles, administered in an intra-ruminal bolus on Day 0; or 100 mg Cu as calcium copper edetate, administered by S/C injection on Days 0 and 58. On Days -5, 14, 28, 58, 86 and 116, liver biopsies and blood samples were obtained for determination of Cu. RESULTS: Mean initial concentrations of Cu in liver for all groups was 827 (SE 42) µmol/kg fresh tissue. In control cows, this decreased to 552 µmol/kg on Day 116, and averaged 670 µmol/kg over the length of the trial. Oral forms of Cu supplementation increased overall mean concentrations in liver to 960 (SE 79), 1,050 (SE 81) and 1,100 (SE 84) µmol/kg for CS, CAC and CG, respectively, but there was no difference between form of supplement. Mean concentrations were significantly increased by bolus treatment, but not by injection. Concentrations of Cu in serum in all groups decreased from 12.1 (SE 0.3) to 10.4 (SE 0.6) µmol/L by Day 116, with no differences due to treatments. The initial concentration of Cu in liver significantly affected the rate of accumulation of Cu among cows supplemented orally. In cows with an initial concentration <1,100 µmol/kg, the average increase was 4.1 µmol/kg fresh tissue/day, whereas rates were variable, even negative, when initial concentrations were >1,100 µmol/kg. Release of Cu over 116 days in cows given the bolus was calculated to be equivalent to an oral intake of CS of 106 mg Cu/day. CONCLUSIONS: In dairy cows with a high Cu status fed a Cu-deficient diet, responses to supplementation with two chelated forms of Cu administrated orally were similar to those due to CS. Copper as CuO was about 77% as effective as oral supplementation with chemically similar inorganic Cu. Initial concentrations of Cu in liver influenced the rate of accumulation following oral supplementation. CLINICAL RELEVANCE: Changes in concentrations of Cu in liver were readily observed following oral supplementation over a wide range of initial concentrations, whereas these changes could not be detected in serum. The liver is thus a good index of the Cu status of dairy cows.

High and variable copper status identified among dairy herds in the Waikato region by concentrations of Cu in liver sourced from biopsies and cull cows

AIMS: To document the Cu supplementation practices on dairy farms in the Waikato region, determine the Cu status of those herds, and compare the suitability of liver samples sourced from biopsies and cull cows for assessing Cu status. METHODS: During spring 2008, concentrations of Cu, Mo and S were determined from pasture samples from 24 dairy farms. Feeding regimens, herd size, milksolids production, soil type, fertiliser policy and Cu supplementation practices were recorded for each property. Based on these data, 10 monitor farms were selected to represent a range of Cu intakes for herds, from 5 to 12 mg Cu/kg dry matter (DM). On each monitor farm 12 healthy lactating cows were selected for liver biopsy and collection of blood samples during the following autumn. Around the same time, livers were collected from 12 cull cows per farm when they were slaughtered, and samples of pasture were again collected from each farm. Concentrations of Cu were measured in all tissue samples. RESULTS: Concentrations of Cu in pasture tended to be higher (mean 10.4 vs 8.2 mg/kg DM) in the autumn than spring, while concentrations of Mo were lower in the autumn (mean 0.35 vs 1.07 mg/kg DM). Most of the 24 farms used Cu supplementation in some form. Mean concentrations of Cu in liver for herds ranged from 640 (SD 544) to 2,560 (SD 474) µmol/kg fresh tissue in biopsies, and 520 (SD 235) to 2,610 (SD 945) µmol/kg in liver from cull cows. Mean concentrations of Cu in serum ranged from 7.9 to 13.4 µmol/L. The variability in concentrations of Cu for each farm was greater for liver (CV 50%) than serum (CV 21%). For individual cows, concentrations of Cu in liver, obtained by biopsy, and serum were not correlated. CONCLUSIONS: The concentration of Cu in liver of dairy cows reflected widely differing dietary intakes of Cu between herds, although levels indicated an adequate Cu status on all farms in this study. Use of either biopsy samples or livers from cull cows were indicative of the Cu status of the herd. Wide variation in observed concentrations of Cu in liver indicated that at least 12 cows per herd should be sampled. On farms with intensive, long-term Cu supplementation programmes there is a risk of chronic Cu toxicity in some animals. Thus, the Cu status of dairy herds should be determined, and monitored, before making any recommendations regarding supplementation.

Interaction of Copper with Iron, Iodine, and Thyroid Hormone Status in Goitrous Patients

In many developing countries, men and women are at high risk of goiter and iron deficiency. The aim of the recent study is to assess the interaction of (Cu), with iron (Fe), iodine/iodide (I), and thyroid hormones in goitrous patients. Sixty goitrous male (GMPs) and 72 female patients (GFPs) were evaluated for the Cu, Fe, I, and thyroid hormones status in biological samples (serum and urine), and compared to non-goitrous subjects of both genders (M = 106, F = 120). The biological samples were analyzed for Cu and Fe concentration using atomic absorption spectrometer, while I was measured by the potentiometric method, prior to microwave-assisted acid digestion (MD). Quality control for the method was established with certified samples. Significantly higher mean values of Cu in serum, and urine samples of GMPs and GFPs, while lower value of Fe and I were observed as compared to control subjects (p < 0.015), respectively. The mean values of free triiodothyronine (FT3) and free thyroxin (FT4) were found to be lower in goitrous patients of both genders than in the age-matched healthy controls (p < 0.006 and 0.002), respectively, in contrast high mean values of thyroid-stimulating hormone (TSH) were detected in patients (p < 0.009), as compared to non-goitrous subjects. It was observed that the deficiencies of Fe, I, and thyroid hormone in goitrous patients could be influenced by efficiency of Cu.

Comparison of concentrations of copper in plasma and serum from farmed red deer (Cervus elaphus)

AIM: To determine the relationship between the concentrations of Cu in plasma and serum in red deer, and to compare this relationship with those previously reported in cattle and sheep. METHODS: Paired serum and heparinised plasma samples from 114 red deer from 10 herds (n=6-20 per herd) were analysed for concentrations of Cu. Samples were collected either at slaughter (n=84; eight herds) or by jugular venepuncture (n=30; two herds). Thirty-nine of the samples taken at slaughter were from adult hinds from four herds, while other samples were taken from 10–14-month-old males, except for one herd (10 samples) where an equal number of 8–9-month-old males and females were sampled. The effect of age, gender and herd on the relationship between concentrations of Cu in plasma and serum was assessed using univariate ANOVA. The individual results for concentrations of Cu in serum were compared with those in plasma, using limits-of-agreement plotting. RESULTS: The mean concentration of Cu in plasma was not significantly different from that of serum (0.048; 95% CI=-0.14 to 0.24 µmol/L). There was no effect of age, sex or herd on this relationship. CONCLUSIONS: In deer, there was no significant difference between concentrations of Cu in plasma and serum regardless of age, sex or herd of origin. CLINICAL RELEVANCE: In contrast to the situation in cattle and sheep, the concentration of Cu in serum can be used interchangeably with that in plasma for the estimation of concentration of Cu in blood of red deer.

Copper deficiency in sheep: An assessment of the relationship between concentrations of copper in serum and plasma

AIM: To assess the relationship between concentrations of copper in serum and plasma in sheep. METHODS: Concentrations of Cu were measured in paired serum and heparinised plasma samples collected from 110 sheep in nine flocks. Linear regression was used to evaluate whether flock or gender had a significant effect on the association between concentrations of Cu in serum and plasma. The individual results for concentrations of Cu in serum were then compared with those from plasma, using correlation and limits of agreement plotting. RESULTS: Concentrations of Cu in serum ranged from 7.3 to 22 (mean 14.0) µmol/L, while concentrations in plasma ranged from 9 to 27 (mean 16.3) µmol/L. On average, concentrations of Cu in serum were 2.3 µmol/L lower than in plasma. Over the range of values seen in this study, concentrations of Cu in plasma and serum were significantly correlated (r=0.89), and mean concentrations in serum were 87% of those in plasma. There was no effect of flock or gender on the relationship between concentrations of Cu in serum and plasma. Despite the significant correlation, there was marked variability between individual samples in the proportion of Cu that was lost during clotting, with the 95% limits of agreement for serum Cu ranging from 70 to 104% of the plasma concentration. CONCLUSIONS: As in cattle, the individual variability in the loss of Cu during clotting in sheep is too great for concentration of Cu in serum to be used as a substitute for that in plasma. CLINICAL RELEVANCE: When assessing the blood Cu pool as part of the diagnosis of Cu-responsive disease in sheep, the concentration of Cu in plasma should be measured in preference to that of serum. We suggest that a range of 4.5 to 9 µmol/L in plasma be used to define marginal Cu status in sheep.

Experimental and Clinical Research on Treatment of Vascular Malformations With Retained Copper Needles

To investigate a simple, safe, and effective surgical approach to treat vascular malformations (VM). Tissues of vein, heart, liver, and kidney were obtained and pathologically observed from 30 rabbits whose central veins of the ears were retained with copper needles, and the concentration of Cu in serum was measured. In the clinical research, 3 methods were employed to treat 89 patients with VM: (1) retaining copper needles alone; (2) ligaturing lesions and retaining copper needles; (3) retaining copper needles charged with direct current (DC). After the treatment of retaining copper needles, thrombus, fibrosis, and necrosis of the malformed vein walls gradually increased. The effective rate was 95.5%. Treatment with copper needles retained in malformed blood vessels leads to denaturalization, fibrosis, and disappearance of the blood vessel structure, and thus it is an effective way to treat VM.

Beneficial Effect of Copper Supplementation on Deposition of Fluoride in Bone in Fluoride- and Molybdenum-Fed Rabbits

Fluorosis is a major public health problem in the world, including India. The present study was undertaken to investigate the role of molybdenum (Mo) in the deposition of fluoride (F) in bone and whether copper (Cu) supplementation has any alleviating role when F and Mo are ingested together. For this purpose, four groups of rabbits were used [control (C), fluoride (F), fluoride + molybdenum (F + Mo), and fluoride + molybdenum + copper (F + Mo + Cu)] to find out the effect of these treatments on various bone-related parameters like intact parathyroid hormone (iPTH), alkaline phosphatase and Cu in serum, hydroxyproline and calcium (Ca) in urine, and minerals (F, Cu, manganese, and zinc) in femur bone ash. Bone mineral content (BMC), bone mineral density (BMD) [by dual energy X-ray absorptiometry (DXA)], and strength of femur bones were also assessed. F content in the femur was significantly higher (P < 0.01) in all experimental groups compared to control group. Mo supplementation increased F deposition in femur bone in the F + Mo group, whereas supplementation of Cu reduced F deposition in the F + Mo + Cu group compared to the F + Mo and F groups. Levels of Cu in femurs of the F + Mo and F + Mo + Cu groups were significantly higher (P < 0.05, P < 0.01, respectively) than in the C group, although serum Cu was significantly lower in the F and F + Mo than the C and F + Mo + Cu groups. Magnesium levels in the F + Mo group were significantly higher (P < 0.05) than in the F and F + Mo + Cu groups. Cu supplementation in the F + Mo + Cu group increased deposition of zinc significantly (P < 0.05) compared to the F and F + Mo groups. Serum iPTH, alkaline phosphatase, and urinary hydroxyproline and Ca were significantly higher (P < 0.01) in the F and F + Mo than in the C and F + Mo + Cu groups. However, serum iPTH and urinary hydroxyproline were higher in the F + Mo group than the F group. Alkaline phosphatase was significantly higher in the F + Mo group than the F and F + Mo + Cu groups. Levels of serum Cu in the F and F + Mo groups were lower than in the C group, though serum Cu was significantly higher in the F + Mo + Cu than in all other groups. DXA analysis of femur bone indicated that BMD in the F + Mo group was significantly higher than in the F (P < 0.05), C (P < 0.01), and F + Mo + Cu (P < 0.05) groups. However, there was no significant difference in BMC among the groups. Bone strength was significantly higher (P < 0.05) in the F + Mo group than in the C group. Results of the present study show that ingestion of Mo with F does not create secondary Cu deficiency (due to increased excretion of Cu through urine). However, Cu concentration was decreased in serum in this group (F + Mo) compared to the C and F + Mo + Cu groups. Deposition of F in femur bone was more (22%) when it was given along with Mo compared to F alone, while F deposition in femur bone was less in the F + Mo + Cu group by 80% compared to the F group. Also, deposition of F in the F + Mo + Cu group was 120% less compared to the F + Mo group. The increase in F level due to Mo addition appears to be offset by supplementation with Cu. Supplementation with Cu showed a beneficial effect on bone resorption as well as bone formation.

Total metal concentrations in serum of dialysis patients and fractionation of Cu, Rb, Al, Fe and Zn in spent continuous ambulatory peritoneal dialysis fluids

Total metal concentrations were determined in the serum of 12 continuous ambulatory peritoneal dialysis (CAPD) patients and in fresh and spent CAPD fluids by electrothermal and flame atomic absorption spectrometry (ETAAS, FAAS). Concentrations of Cu in serum of CAPD patients ranged from 720 to 1780 ng cm −3, Rb from 128 to 346 ng cm −3, Al from 10 to 72 ng cm −3, Fe from 800 to 2300 ng cm −3 and Zn from 659 to 1310 ng cm −3. The accuracy of the analytical procedure was checked by the analysis of the reference material Seronom™, Trace Elements in Serum. Good agreement between the certified and determined values was obtained for Al, Cu, Fe and Zn. The data on the total metal concentrations in CAPD fluids indicated that during CAPD fluid exchange the losses of Cu from 5.0 to 35 ng cm −3, of Rb from 50 to 110 ng cm −3 and of Al from 3.0 to 14.0 ng cm −3 occurred through the peritoneal membrane. Although fresh CAPD fluids contained traces of Fe (3.0–5.0 ng cm −3), the transfer of this element took place through the peritoneal membrane into spent CAPD fluid (13.0–38.0 ng cm −3). Zn concentrations were in general lower in spent (20.0–80 ng cm −3) than in fresh CAPD fluids (∼100 ng cm −3). To follow the mechanisms of the transfer of trace elements through the peritoneal membrane of CAPD patients, fractionation of metals was carried out in spent CAPD fluids by size exclusion chromatography with UV and AAS detection, applying Superdex HR 10/30 column. The chromatographic run was followed at 278 nm and separated metal species also determined ‘off line’ in 1 cm 3 fractions by ETAAS or FAAS. From the UV chromatograms and AAS analysis of trace elements in the separated fractions it was demonstrated that Cu, Al, Fe and Zn were bound to proteins and only partially to low molecular weight (LMW) species, while Rb was associated exclusively with LMW species. For characterisation of the high molecular weight (HMW) binding proteins, fractions containing trace elements were subjected to SDS-PAGE electrophoresis. Al and Fe were presumably bound to transferrin, but due to its low concentration in spent CAPD fluids, it was not possible to confirm its presence in the separated fractions. About 10% of Al and 15% of Fe corresponded to LMW species. A fraction of HMW proteins of Cu in spent CAPD fluids was most probably bound to albumin and Zn to albumin and globulins. About 50% of Cu and Zn existed in LMW proteins, while Zn was also found partially in ionic form.

Modulation of Age-Related Biochemical Changes and Oxidative Stress by Vitamin C and Glutathione Supplementation in Old Rats

The present study sought to determine whether supplementation of dietary antioxidant ascorbic acid with glutathione (GSH) could ameliorate the age-related increased oxidative stress and changes in hormonal, lipid and copper (Cu) as well as zinc (Zn) levels in 18-month-old rats. The present study demonstrated that supplementation of vitamin C (30 mg) + GSH 100 mg/kg b.w. significantly reduced the concentration of thiobarbituric acid-reactive substances in liver and testes in old male rats as compared with nonsupplemented ones, indicating lower oxidative stress. In addition, testicular GSH was increased but not hepatic GSH. Also, cholesterol and triglycerides were decreased in the serum of supplemented rats. Furthermore, she serum testosterone level was increased in the same supplemented rats. However, the present results show that the thyroid hormones, T₃ and T₄, were not influenced. Lastly, the concentration of Cu in serum, liver, brain and testes was increased in supplemented old rats. Zn concentration was also increased in the same organs but not in the liver. According to the present study, the supplementation of antioxidants could play an important role in the modulation of the oxidative damage and changes associated with age.

Dietary fibre on cell proliferation in large bowel mucosal crypts near or away from lymphoid nodules and on mineral bioavailability.

The effect of consumption for 24 weeks of different amounts (0%, 5% or 10% w/w) of fermentable (pectin and guar gum) or nonfermentable (cellulose and lignin) dietary fibres on cell proliferation and other parameters in large bowel mucosal crypts was studied in rats. In all 12 dietary groups, the crypts located over the distal aggregate of lymphoid nodules (ALN) had more colchicine arrested metaphase figures per midaxial crypt section (MC) and a longer crypt column height than crypts located three to four cm away from this ALN. These differences are attributed to the tropic influence of nodular cells in the ALN. Consumption of fermentable fibre decreased pH in the lumen of the caecum, and glucose, Zn and Cu in serum but increased Ca and Mg in serum. The decrease in caecal pH and serum glucose was significantly correlated with a decrease in MC. Increased intake of the nonfermentable fibre types increased faecal bulk but had no significant correlation with the other measured crypt parameters. Multiple regression analyses was used to model the relationships between the mucosal crypt criterion variables and the two measured predictor variables, caecal pH and serum glucose. Relationships between dietary fibre, ALN, MC, bioavailability of dietary minerals and risk of colorectal cancer are discussed.

Oxidase Activity of Ceruloplasmin and Concentrations of Copper and Zinc in Serum in Chronic Arterial Occlusion of the Lower Limbs

The presence of ischaemic tissue excites an inflammatory reaction and synthesis of acute phase proteins (APhPs). Ceruloplasmin (Cp) protein binds 90% of the copper in plasma and it is one of the positive APhPs, and its concentration increases in infection, inflammation or necrosis. The study presents the relationship of the oxidase activity of Cp and concentrations of Cu and Zn in serum of men with different degrees of ischaemia of the lower limbs. The subjects were 32 men with chronic arterial occlusion (AO) of the lower limbs. The oxidase activity of Cp was measured in serum with o-dianisidine as a substrate. Concentrations of Cu and Zn were determined by using atomic absorption spectrometry. The mean activity of Cp in serum in AO (173 +/- 69.2 U/l) was higher as compared with the control group (123.7 +/- 28.6 U/l), and in men with critical ischaemia (> or = 194.8 U/l) than in men with a moderate level of ischaemia (109.3 +/- 31.6 U/l). The mean concentrations of Cu and Zn in serum were found to be higher in AO (22.2 +/- 4.2 and 19.1 +/- 6.9 mumol/l, respectively) than in the control group (16.3 +/- 1.8 and 15.2 +/- 2.3 mumol/l), and in men with critical ischaemia (> or = 22.2 and 19.1 mumol/l) than in men with a moderate level of ischaemia (18.5 +/- 3.3 and 14.5 +/- 4.3 mumol/l). Significant positive correlation coefficients were calculated for the activities of Cp and concentrations of Cu in the control group (r = 0.86) and the AO group (r = 0.76), and low, but significant, correlations for Cp and Zn in the AO group (r = 0.66). The increase in the oxidase activity of Cp and concentration of Cu in serum in ischaemia is caused by the acute phase response. The relationship of Zn concentration and Cp activity in ischaemia is indirect and needs further study.

Estradiol replacement and dietary copper in ovariectomized rats additively increase the serum levels of HDL cholesterol and body status of copper

The present study was conducted to determine the interactive effects of dietary copper (Cu) and estradiol (ES) on Cu status and serum HDL cholesterol in ovariectomized (OX) rats. Rats were divided into the following three groups of 12 each: 1) OX0 group: without ES replacement; 2) OXE group: with ES replacement (OXE); and 3) SM group: sham-operated with intact ovaries. After postoperative recovery for 3 weeks, the OXE rats were implanted subcutaneously with a 1.5 mg pellet of 17β-estradiol, and the OX0 and SM rats were implanted with a placebo pellet. Each of the three groups was then subdivided into two groups: one was fed a Cu-deficient (−Cu) diet (0.99 μg Cu/g), and the other a Cu-adequate (+Cu) diet (7.0 μg Cu/g). Time course changes in serum HDL-cholesterol (HDL-C), ES, and Cu were determined. Serum HDL cholesterol was determined after separation of the HDL fraction by affinity chromatography. Serum ES was determined by radioimmunoassay. ES replacement sharply increased the concentrations of Cu in serum and liver regardless of whether rats were fed the −Cu or +Cu diet. ES replacement also produced a selective increase in HDL-C. It ranged from 1.5 to 2.2 mmol/L in OXE rats, whereas the range in OX0 was between 1.0 and 1.4 mmol/L, as determined at days 20, 40, and 60. Dietary Cu did not affect the concentrations of total serum or HDL cholesterol at days 20 and 40. However, at day 60, serum HDL-C was significantly lower in the rats fed the −Cu diet than in those fed the +Cu diet, independent of ES replacement. Serum HDL-C in all groups were correlated significantly with serum ES (r = 0.60, P < 0.0006). Serum Cu was correlated highly with serum HDL cholesterol (r = 0.66, P < 0.0001) and serum ES (r = 0.64, P < 0.0001). The results provide evidence that ES replacement in OX rats selectively increases the serum levels of HDL cholesterol. The increase in serum HDL is independent of the nutritional status of Cu but is associated with a parallel rise in serum ES in response to ES replacement. The present finding and earlier observations, taken together, suggest a specific role of ES in protecting HDL during circulation and in improving the body status of Cu. J. Trace Elem. Exp. Med. 11:45–58, 1998. © 1998 Wiley-Liss, Inc.

Marginal copper-restricted diets produce altered cardiac ultrastructure in the rat.

To determine if chronic ingestion of a diet containing a marginally low level of Cu could cause deleterious alterations in cardiac ultrastructure, male offspring were nursed by dams fed a diet containing either 6.7 or 2.8 mg Cu/kg from midgestation through lactation before weaning to the same diet. Conventional measures of Cu status, including growth, relative heart weight, tissue concentrations of Cu, ceruloplasmin activity, and tissue activity of Cu,Zn-superoxide dismutase (SOD) were similar in both dietary treatment groups at 5.5 months of age. However, significant increases in the number and volume of lipid droplets and an increased incidence of pathological abnormalities in mitochondria and basal laminae were observed in sections of hearts from rats chronically fed the diet containing 2.8 mg/kg Cu. Reduction of the dietary level of Cu from 2.8 to 1.3 mg/kg from 4 to 5.5 months of age caused significant reductions in the concentration of Cu in serum and liver, but Cu content, Cu,Zn-SOD activity, pathological scores, and morphometric parameters in hearts were not modified by the greater restriction of dietary Cu in adult rats. This study suggests that abnormalities in cardiac ultrastructure occurred in rats chronically fed diets marginally low in Cu, despite minimal changes in conventional biochemical indicators of Cu status.