Low Dietary Copper Research Articles

Moderate Copper Deprivation during Gestation and Lactation Affects Dentate Gyrus and Hippocampal Maturation in Immature Male Rats

The hippocampal formation (HF) is involved in higher brain functions including learning and declarative memory. The possibility that dietary copper has a role in the morphological development, and therefore the function of the HF, has received little attention. A rat model of tiered copper deficiency, initiated during gestation, was employed to determine the susceptibility of the HF, regions of which develop postnatally, to copper deficiency. At postnatal 23, pups whose dams had received either 1.8 or 1.4 mg Cu/kg diet during both gestation and lactation, compared with offspring of a group that had received 4.3 mg Cu/kg diet during both periods had, significantly more cell nuclei in the infrapyrimidal arm of the dentate gyrus. Offspring of rats fed 1.4 mg Cu/kg diet, but not those fed 1.8 mg/kg, compared with those fed 4.3 mg/kg, exhibited smaller, shorter, and narrower cell nuclei in the infrapyrimidal and suprapyrimidal arms of the dentate gyrus and smaller cell nuclei in region CA3c of the hippocampus. A fourth group (gestation, 1.8 mg Cu/kg diet; lactation, 0.9 mg Cu/kg diet) exhibited alterations less marked than those exhibited by the group fed 1.4 mg Cu/kg diet. All alterations in the groups fed low copper diets were consistent with slowed cell nuclear maturation. The findings indicate that copper is required for maturation of the dentate gyrus and hippocampus. Also, copper supplied at or below 1.8 mg/kg is insufficient for morphological maturation of the dentate gyrus and hippocampus. Because the HF is important for higher brain functions, further research is needed to determine whether the copper deficiency-induced alterations in dentate gyrus and hippocampus development are transient or permanent.

Latest innovations in the treatment of Wilson's disease

Wilson's disease (WD), also called hepatolenticular degeneration, is an autosomal recessive copper dysfunction disorder that is among the few treatable neurogenetic disorders. The main goals for controlling WD are to lower copper intake and encourage copper removal. Medical treatments and low-copper diets are available, but many problems remain. For example, current treatments cannot fix copper metabolism and are unable to cross the blood–brain barrier. Furthermore, severe side effects have been experienced by many WD patients. Because lifelong therapy is required for this disease, adherence to medical therapy and best practices for monitoring and personalizing therapy continue to evolve; some of these issues are being addressed in ongoing studies. Additionally, novel chelating agents, gene therapies using adeno-associated viruses, and variant-specific therapies that may improve neurological outcomes are in development. Here, we review the latest treatment innovations that may play an essential role for WD patients in the future. • Wilson's disease (WD) is one of the few neurogenetic diseases that can be treated. • Current treatments neither can fix the copper metabolism nor cross the blood-brain barrier (BBB). • Besides, severe side effects have been experienced by many WD patients. • Novel chelating agents, gene therapy, and variant-specific treatments are in development.

118 Effects of dietary copper levels on growth performance and response to lipopolysaccharide challenge in nursery pigs from sows fed either high or low copper diets

118 Effects of dietary copper levels on growth performance and response to lipopolysaccharide challenge in nursery pigs from sows fed either high or low copper diets

Deficient copper concentrations in dried-defatted hepatic tissue from ob/ob mice: A potential model for study of defective copper regulation in metabolic liver disease

Ob/ob mice provide an animal model for non-alcoholic fatty liver disease/non-alcoholic steatohepatitis (NAFLD/NASH) in patients with obesity and type-2 diabetes. Low liver copper has been linked to hepatic lipid build-up (steatosis) in animals with systemic copper deficiency caused by low-copper diets. However, hepatic copper status in patients with NAFLD or NASH is uncertain, and a validated animal model useful for the study of hepatic copper regulation in common forms of metabolic liver disease is lacking. Here, we report parallel measurements of essential metal levels in whole-liver tissue and defatted-dried liver tissue from ob/ob and non-obese control mice. Measurements in whole-liver tissue from ob/ob mice at an age when they have developed NAFLD/NASH, provide compelling evidence for factitious lowering of copper and all other essential metals by steatosis, and so cannot be used to study hepatic metal regulation in this model. By marked contrast, metal measurements in defatted-dried liver samples reveal that most essential metals were actually normal and indicate specific lowering of copper in ob/ob mice, consistent with hepatic copper deficiency. Thus ob/ob mice can provide a model useful for the study of copper regulation in NAFLD and NASH, provided levels are measured in defatted-dried liver tissue.

Dietary copper supplementation restores β-cell function of Cohen diabetic rats: a link between mitochondrial function and glucose-stimulated insulin secretion

β-Cell mitochondrial dysfunction as well as proinflammatory cytokines have been suggested to contribute to reduced glucose-stimulated insulin secretion (GSIS) in type 2 diabetes. We recently demonstrated that Cohen diabetic sensitive (CDs) rats fed a high-sucrose, low-copper diet (HSD) developed hyperglycemia and reduced GSIS in association with peri-islet infiltration of fat and interleukin (IL)-1β-expressing macrophages, whereas CD resistant (CDr) rats remained normoglycemic on HSD. We examined: 1) the correlation between copper concentration in the HSD and progression, prevention, and reversion of hyperglycemia in CDs rats, 2) the relationship between activity of the copper-dependent, respiratory-chain enzyme cytochrome c oxidase (COX), infiltration of fat, IL-1β-expressing macrophages, and defective GSIS in hyperglycemic CDs rats. CDs and CDr rats were fed HSD or copper-supplemented HSD before and during hyperglycemia development. Blood glucose and insulin concentrations were measured during glucose tolerance tests. Macrophage infiltration and IL-1β expression were evaluated in pancreatic sections by electron-microscopy and immunostaining. COX activity was measured in pancreatic sections and isolated islets. In CDs rats fed HSD, GSIS and islet COX activity decreased, while blood glucose and infiltration of fat and IL-1β-expressing macrophages increased with time on HSD (P < 0.01 vs. CDr-HSD rats, all parameters, respectively). CDs rats maintained on copper-supplemented HSD did not develop hyperglycemia, and in hyperglycemic CDs rats, copper supplementation restored GSIS and COX activity, reversed hyperglycemia and infiltration of fat and IL-1β-expressing macrophages (P < 0.01 vs. hyperglycemic CDs-HSD rats, all parameters, respectively). We provide novel evidence for a critical role of low dietary copper in diminished GSIS of susceptible CDs rats involving the combined consequence of reduced islet COX activity and pancreatic low-grade inflammation.

Effects of clonidine and idazoxan on tetrathiomolybdate-induced copper and lysosomal enzyme excretion into sheep bile

This study investigated the effects of intravenous (IV) administration of tetrathiomolybdate (TTM), and α(2)-adrenergic agonist clonidine (CLO) and α(2)-antagonist idazoxan (IDA), alone or in combination with TTM, on sheep fed low (LCu) and high (HCu) copper diets. Effects on bile flow, biliary Cu concentration and excretion, plasma Cu concentration, and lysosomal enzyme β-glucuronidase (β-GLU) activity in bile and plasma were determined. Tetrathiomolybdate alone or with CLO or IDA significantly enhanced biliary Cu excretion most likely by removing Cu from hepatocyte lysosomes as evidenced by a significant increase in β-GLU enzyme activity in bile. A significant increase in plasma β-GLU concentration occurred only in sheep treated with CLO in combination with TTM. Because of the lytic nature of the lysosomal enzymes, caution is advocated in use of drugs, especially α(2)-adrenergic agonists, to further enhance TTM-induced biliary Cu excretion in the treatment of chronic Cu poisoning in sheep.

Dietary Management of Hepatic Copper Accumulation in Labrador Retrievers

Copper-associated chronic hepatitis (CACH) recently has been recognized in the Labrador Retriever as an inherited disorder with a late onset of clinical signs. No studies have investigated dietary management for the long-term treatment of this disease or for its potential in delaying the onset of clinical signs in subclinical cases. To investigate the effects of a low-copper diet and zinc gluconate on hepatic copper concentrations in Labrador Retrievers with abnormal hepatic copper concentrations. Twenty-four client-owned Labradors that were related to patients affected with CACH and that had been diagnosed with increased hepatic copper concentrations. Hepatic copper concentrations were assessed before and after an average of 8 and 16 months of treatment. During this time, all dogs were fed exclusively a low-copper diet. In addition, dogs were assigned to 1 of 2 groups in a randomized double-blind manner to receive a supplement of zinc gluconate or placebo. Twenty-one dogs completed the study. Hepatic copper concentrations decreased in both groups at recheck 1 (n = 21; group 1, P < .001; group 2, P= .001) and at recheck 2 (n= 16; group 1, P= .03; group 2, P= .04). No difference in hepatic copper concentrations was found between the 2 groups before treatment (P= .65), at recheck 1 or at recheck 2 (P= .52-.79). Feeding low-copper diets to Labradors is effective in decreasing hepatic copper concentrations. Adjunctive treatment with zinc does not appear to increase the copper-lowering effects of dietary management.

Low-copper diets increase aortic lipid peroxides in rats.

Dietary factors other than fat and cholesterol may contribute to the pathogenesis of cardiovascular disease. One hypothesis states that low dietary copper contributes to risk. In a recent study, rats fed diets marginal or deficient in copper had reduced aortic copper-dependent superoxide dismutase activity, increased generation of aortic lipid peroxides, and reduced aortic prostaglandin production. These vascular changes may contribute to atherogenesis.

Cardiac Cytochrome c Oxidase Activity and Contents of Subunits 1 and 4 Are Altered in Offspring by Low Prenatal Copper Intake by Rat Dams

It has been reported previously that the offspring of rat dams consuming low dietary copper (Cu) during pregnancy and lactation experience a deficiency in cardiac cytochrome c oxidase (CCO) characterized by reduced catalytic activity and mitochondrial and nuclear subunit content after postnatal d 10. The present study was undertaken to determine whether the cardiac CCO deficiency was caused directly by low postnatal Cu intake or whether it was a prenatal effect of low Cu intake by the dams that became manifest postnatally. Dams were fed either a Cu-adequate diet (6 mg Cu/kg) or Cu-deficient diet (1 mg Cu/kg) beginning 3 wk before conception and throughout gestation and lactation. One day following parturition, several litters from Cu-adequate dams were cross fostered to Cu-deficient dams and several litters from Cu-deficient dams were cross fostered to Cu-adequate dams. Litters that remained with their birth dams served as controls. CCO activity, the content of the mitochondrial-encoded CCO subunit 1 (COX1), and the content of the nuclear-encoded subunit COX4 in cardiac mitochondria were reduced in the 21-d-old offspring of Cu-deficient dams. COX1 content was normal in the 21-d-old cross-fostered offspring of Cu-deficient dams, but CCO activity and COX4 were reduced. Cross fostering the offspring of Cu-adequate dams to Cu-deficient dams did not significantly affect CCO activity, COX1 content, or COX4 content in cardiac mitochondria of 21-d-old offspring. These data indicate that low prenatal Cu intake by dams was the determinant of CCO activity in cardiac mitochondria of the 21-d-old offspring and may have led to the assembly of a less-than-fully active holoenzyme.

Exposure to low dietary copper or low copper coupled with high dietary manganese for one year does not alter brain prion protein characteristics in the mature cow1,2

It is now widely accepted that abnormal prion proteins are the likely causative agent in bovine spongiform encephalopathy. Cellular prion proteins (PrP(c)) bind Cu, which appears to be required to maintain functional characteristics of the protein. The replacement of Cu on PrP(c) with Mn has resulted in loss of function and increased protease resistance. Twelve mature cows were used to determine the effects of Cu deficiency, alone and coupled with high dietary Mn, on brain Cu and Mn concentrations and on PrP(c) functional characteristics. Copper-adequate cows were randomly assigned to treatments: 1) control (adequate in Cu and Mn), 2) Cu-deficient (-Cu), and 3) Cu-deficient plus high dietary Mn (-Cu+Mn). Cows assigned to treatments -Cu and -Cu+Mn received no supplemental Cu and were supplemented with Mo to further induce Cu deficiency. After 360 d, Cu-deficient cows (-Cu and -Cu+Mn) tended to have lesser concentrations of Cu (P = 0.09) in the obex region of the brain stem. Brain Mn tended (P = 0.09) to be greater in -Cu+Mn cattle compared with -Cu cattle. Western blots revealed that PrP(c) relative optical densities, proteinase K degradability, elution profiles, molecular weights, and glycoform distributions were not different among treatments. The concentration of PrP(c), as determined by ELISA, was similar across treatment groups. Brain tissue (obex) Mn superoxide dismutase activity was greatest (P = 0.04) in cattle receiving -Cu+Mn, whereas immunopurified PrP(c) had similar superoxide dismutase-like activities among treatments. Immunopurified PrP(c) had similar Cu concentrations across treatments, whereas Mn was undetectable. We concluded that Cu deficiency, coupled with excessive Mn intake, in the bovine may decrease brain Cu and increase brain Mn. Copper deficiency, alone or coupled with high dietary Mn, did not cause detectable alterations in PrP(c) functional characteristics.

Assessment of zinc and copper status in weaned piglets in relation to dietary zinc and copper supply

The aim of the study was to determine the effect of weaning and the effect of increasing dietary zinc concentrations on the zinc and copper status of weaned piglets (study 1) and to study the effect of high concentrations of dietary zinc and/or copper on zinc and copper status of weaned piglets (study 2). Study 1 included 54 piglets (six litters of nine piglets). One piglet from every litter was killed 1 day before weaning. The remaining 48 piglets were allocated at weaning (28 days) to four dietary zinc treatments (100, 250, 1000 or 2500 ppm) and subsequently killed 1-2, 5-6 or 14-15 days after weaning. Study 2 included 48 piglets (six litters of eight piglets) allocated to four dietary treatments, consisting of low or high dietary zinc (100 or 2500 ppm) in combination with low or high dietary copper (20 or 175 ppm). All piglets in study 2 were killed 5-7 days after weaning. In both studies, the trace mineral status was assessed by zinc and copper concentrations and alkaline phosphatase (AP) activity in plasma and mucosal tissue. In study 2, lymphocyte metallothionein (MT) mRNA and intestinal mucosa MT mRNA concentrations were included as zinc status markers. The results showed that the zinc status, measured as zinc in plasma and mucosa, was not affected by weaning of the piglets. Plasma copper concentrations decreased during the first 2 weeks after weaning. High dietary copper concentrations did not affect the concentration of copper in plasma, but increased the concentration of copper in mucosa and the concentration of zinc in plasma. The dietary zinc treatments increased the zinc concentration in plasma as well as the zinc and MT mRNA concentration in mucosa. Lymphocyte MT mRNA concentrations did not reflect the differences in dietary zinc supplementation.

Hearts in adult offspring of copper-deficient dams exhibit decreased cytochrome c oxidase activity, increased mitochondrial hydrogen peroxide generation and enhanced formation of intracellular residual bodies

The long-term effects of low dietary copper (Cu) intake during pregnancy and lactation on cardiac mitochondria in first-generation adult rats was examined. Rat dams were fed diets containing either low (1 mg/kg Cu) or adequate (6 mg/kg Cu) levels of dietary Cu beginning 3 weeks before conception and ending 3 weeks after birth. Cytochrome c oxidase (CCO) activity was 51% lower in isolated cardiac mitochondria from 21-day-old offspring of Cu-deficient dams than in the offspring of Cu-adequate dams. CCO activities in the cardiac mitochondria of 63- and 290-day-old offspring were 22% lower and 14% lower, respectively, in the offspring of Cu-deficient dams after they had been repleted with adequate dietary Cu from the time they were 21 days old. Electron micrographs showed that the size of residual bodies and the cellular volume they occupied in cardiomyocytes rose significantly between 63 and 290 days in the Cu-repleted offspring of Cu-deficient dams, but not in the offspring of Cu-adequate dams. The rate of hydrogen peroxide generation by cardiac mitochondria also was 24% higher in the 290-day-old repleted offspring of Cu-deficient dams than in the offspring of Cu-adequate dams. The increase in hydrogen peroxide production by cardiac mitochondria and in the relative volume and size of dense deposits in cardiomyocytes is consistent with increased oxidative stress and damage resulting from prolonged reduction of CCO activity in the offspring of Cu-deficient dams.

Cardiac Cytochrome-c Oxidase Deficiency Occurs During Late Postnatal Development in Progeny of Copper-Deficient Rats

Although cytochrome-c oxidase (CCO) is a copper-dependent enzyme, the effect of maternal copper deficiency on the expression of CCO activity during postnatal development of the neonatal rat heart has not been investigated extensively. Here, we show that CCO activity in heart mitochondria isolated from neonates of copper-deficient dams did not exhibit significant reductions until postnatal days (PND) 15 and 21. In addition, immunoblot analysis indicated that the CCO subunit (Cox-1) was reduced on postnatal Days 10 and 21, and that Cox-4 was reduced on PND 21 in heart mitochondria of the neonates from copper-deficient dams. These findings indicate that the impairment of CCO activity in neonatal heart by maternal copper deficiency occurs late in the postnatal heart development. Furthermore, the concurrent reductions in Cox-1 and Cox-4 suggest that the impaired CCO activity reflects a CCO deficiency in heart mitochondria. CCO activity and Cox-1 in heart mitochondria were not fully restored by 6 weeks of postweaning copper repletion in the pups of copper-deficient dams. This indicates that prolonged maternal intake of moderately low dietary copper produces CCO deficiency in cardiac mitochondria of neonates during late postnatal heart development, after terminal differentiation of cardiomyocytes occurs. The resistance of CCO deficiency to repair by dietary copper supplementation may be related to the relatively slow turnover of the affected mitochondria in the terminally differentiated heart.

Some magnesium status indicators and oxidative metabolism responses to low-dietary magnesium are affected by dietary copper in postmenopausal women

A study with human volunteers was conducted to ascertain whether a low intake of copper (Cu) would exacerbate the response to a deficient intake of magnesium (Mg). Nineteen postmenopausal women, age 47 to 78 y, completed a metabolic unit study as designed. For 162 d, nine women were fed a diet containing 1.0 mg of Cu/2000 kcal and 10 women were fed 3.0 mg of Cu/2000 kcal. Diets contained 99 or 399 mg of Mg/2000 kcal for 81 d in a randomized, double-blind, crossover design. Differences were considered significant when statistical analysis yielded P </= 0.05. Magnesium balance was highly positive when the dietary magnesium was high but non-positive when dietary magnesium was low. Copper balance was more positive when dietary copper was high than when it was low. Plasma ionized magnesium was decreased by magnesium deprivation. Several variables measured indicated that low dietary copper affected the response to magnesium deprivation or vice-versa. Red blood cell magnesium was lower when dietary copper was low than when it was high. When dietary magnesium was low, serum copper was lower in the women fed marginal copper than in those fed luxuriant copper. When dietary magnesium was high, low dietary copper did not affect serum copper. Magnesium deprivation decreased red blood cell superoxide dismutase when dietary copper was luxuriant; when dietary copper was low, magnesium deprivation did not have much of an effect. Apolipoprotein A1 was lowest when dietary magnesium and copper were low. The order in which the magnesium restriction occurred affected the response of a number of variables to this treatment including concentrations of serum magnesium and total and low-density lipoprotein cholesterol. The findings indicated that, in short-term magnesium depletion experiments, the response to depletion can be influenced by other dietary factors including copper intake and a high magnesium intake before depletion, and that 100 mg of Mg/d is inadequate for postmenopausal women.

Low Dietary Copper Increases Fecal Free Radical Production, Fecal Water Alkaline Phosphatase Activity and Cytotoxicity in Healthy Men

One possible dietary factor that may increase susceptibility to colon cancer is inadequate copper intake. The objective of this study was to investigate the effects of low and adequate copper intakes on copper nutriture and putative risk factors for colon cancer susceptibility in healthy men. Seventeen healthy free-living nonsmoking men aged 21-52 y completed a 13-wk controlled feeding study in a randomized crossover design. The basal diet contained 0.59 mg Cu/13.65 MJ. After a 1-wk equilibration period in which the men consumed the basal diet supplemented with 1.0 mg Cu/d, they were randomly assigned to receive either the basal diet or the basal diet supplemented with 2 mg Cu/d for 6 wk. After the first dietary period, the men immediately began to consume the other level of Cu for the last 6 wk. They collected their feces during the equilibration period and during the last 2 wk of the two dietary periods for free radical and fecal water analysis. Low dietary copper significantly (P < 0.01) increased fecal free radical production and fecal water alkaline phosphatase activity. Low dietary copper significantly (P < 0.0001) decreased fecal water copper concentrations but did not affect fecal water volume, pH, iron or zinc concentrations. In contrast to the fecal analysis, hematological indicators of copper status were not significantly affected by the dietary treatments. These results suggest that low dietary copper adversely affects fecal free radical production and fecal water alkaline phosphatase activity, which are putative risk factors for colon cancer.

High dietary fructose compared with corn starch does not heighten changes in copper absorption, retention, or status indicators in men fed low dietary copper

AbstractIn experimental animals, high dietary fructose exacerbates signs of copper deficiency in rats. Thus, an experiment was performed to determine whether high dietary fructose affected copper metabolism and copper status indicators in healthy men who were fed low dietary copper. Six men aged 27 to 37 years completed a metabolic unit study divided into four 7‐week dietary periods with a randomized, double‐blind, 2 × 2 factorial design with variables of 0.6 or 2.6 mg Cu/2500 kcal and fructose or corn starch as 20% of energy. Twice during each dietary period the men consumed a standardized breakfast meal labeled with 2.5 μCi 67Cu, then were counted daily in a whole‐body counter for 3 weeks after each meal. At the end of each dietary period, blood was collected to assess copper status. Neither type of dietary carbohydrate nor intake of copper significantly affected 67Cu absorption, but copper deprivation resulted in a negative copper balance. The source of dietary carbohydrate did not affect the biological half‐life of copper, but it was significantly (P &lt; 0.001) longer when dietary copper was low (35 ± 11 d; mean ± SD) than when supplemented (20 ± 5 days). The natural log of the biological half‐life directly correlated with plasma copper (r = 0.498; P = 0.001) and immunoreactive, or radial immunodiffusion, ceruloplasmin (RID Cp; r = 0.394; P = 0.013), and was inversely related to glutathione (r = −0.510, P = 0.03). When high dietary fructose was fed, erythrocyte superoxide dismutase activity and RID Cp was lower, and the enzymatic ceruloplasmin/RID Cp ratio was higher during copper depletion than during repletion; just the opposite occurred when corn starch was fed. No other copper status indicator was affected by an interaction between dietary carbohydrate and copper or was heightened by high dietary fructose. The results indicate that men fed approximately 0.6 mg Cu/d for 7 weeks attempted to adapt to this low intake by retaining absorbed copper longer. The adaptation was inadequate because copper balance became negative. However, although copper status was decreased, the response of men to short‐term dietary copper deprivation was not heightened by high dietary fructose. J. Trace Elem. Exp. Med. 16:27–38, 2003. © 2003 Wiley‐Liss, Inc.

Effects of copper supplementation on the copper status of peripartum beef cows and their calves

The effects of copper supplementation on the copper status of 40 late-pregnant Aubrac beef cows grazing a copper-deficient pasture and later fed a marginally deficient diet were studied for five...

Dietary Copper Affects Azoxymethane-Induced Intestinal Tumor Formation and Protein Kinase C Isozyme Protein and mRNA Expression in Colon of Rats

Previous studies have show that changes in protein kinase C (PKC) isoform expression may be related to increased susceptibility of copper-deficient rats to aberrant crypt formation. The purpose of this study was to determine whether dietary copper would affect azoxymethane-induced intestinal tumor formation and PKC isozyme expression in normal colonic mucosa and tumor samples. Eighty weanling Fischer-344 rats were randomly assigned to diets that contained either 0.8 or 5.3 microg Cu/g diet. After 24 and 31 d of diet consumption, 30 rats/diet were administered azoxymethane (15 mg/kg i.p.) and 10 rats/diet were administered saline. Rats continued to consume their respective diets for an additional 38 wk. Rats injected with azoxymethane and fed the low copper diet had a significantly (P < 0.0001) greater small intestinal and total tumor incidence compared with rats fed adequate dietary copper. However, dietary copper did not affect colon tumor incidence. Low dietary copper significantly (P < 0.004) decreased PKC alpha protein expression in normal but not in tumor tissue. In contrast, low dietary copper did not affect PKC delta or zeta protein expression in either the normal or tumor tissue. PKC alpha and delta protein and mRNA expression were lower in tumor tissue than in normal tissue. These results along with previous observations suggest that dietary copper-mediated changes in PKC alpha, delta and zeta protein expression are not as important for colon tumor promotion/progression as they are for tumor initiation.

Medication and Dietary Practices of Independent Living Healthy African-American Older Persons

The main objective of this study was to determine the dietary and medication practices of independent-living African-Americans aged 55 years and older. Forty-one women and 19 men completed a detailed in-home drug survey. A questionnaire was used to gather demographic information and a 3-day dietary record. Results indicate that on a daily basis 17% of the respondents were taking four prescribed medications and 7% were taking four over-the-counter medications. In addition, on a daily basis 7% of the respondents were taking five prescribed medications and 14% were taking five over-the-counter medications. Respondents with less than a high school education reported the total percentage of calories ingested from fat was 36%, at the p < 0.01 level, while respondents with a high school education or greater reported a 30% indigestion. The results also indicate a low caloric intake and a low dietary calcium, magnesium, zinc, and copper intake. Research indicates drugs often deplete these minerals.

Dietary copper and dimethylhydrazine affect protein kinase C isozyme protein and mRNA expression and the formation of aberrant crypts in colon of rats.

Low dietary copper has been shown to decrease the expression of various protein kinase C (PKC) isozymes and increase the risk of colon cancer development in experimental animals. The purpose of this study was to investigate the relationship between dietary copper and carcinogen administration on PKC isozyme accumulation and aberrant crypt foci (ACF) formation in rats fed 0.9 and 7.7 microg Cu/g diet. After 24 and 31 d on the diets, the rats were injected with either dimethylhydrazine (DMH) (25 mg/kg i.p.) or saline and killed at two time points (2 wk and 8 wk after DMH). Rats fed low dietary copper had significantly lower (p<0.0001) hematocrits, hemoglobin, ceruloplasmin activity and plasma and liver copper concentrations than rats fed adequate dietary copper. Ingestion of low dietary copper significantly (p<0.005) increased the formation of DMH-induced ACF (116.8 vs 59.6). Low dietary copper significantly (p<0.05) decreased the concentration of PKC alpha, delta, and zeta in the colon at 2 wk but not at 8 wk. Thus, changes in PKC isoform protein concentration may be related to increased susceptibility of copper-deficient animals to colon cancer.