Abnormal motor function persists following recovery from perinatal copper deficiency in rats

Protein Carbonyl, Lipid Peroxidation, Glutathione and Enzymatic Antioxidant Status in Male Wistar Brain Sub-regions After Dietary Copper Deficiency

Copper a quintessential transitional metal is required for development and function of normal brain and its deficiency has been associated with impairments in brain function. The present study investigates the effects of dietary copper deficiency on brain sub-regions of male Wistar rats for 2-, 4- and 6-week. Pre-pubertal rats were divided into four groups: negative control (NC), copper control (CC), pairfed (PF) and copper deficient (CD). In brain sub regions total protein concentration, glutathione concentration and Cu-Zn SOD activity were down regulated after 2-, 4- and 6 weeks compared to controls and PF groups. Significant increase in brain sub regions was observed in protein carbonyl and lipid peroxidation concentration as well as total SOD, Mn SOD and catalase activities after 2-, 4- and 6 weeks of dietary copper deficiency. Experimental evidences indicate that impaired copper homeostasis has the potential to generate reactive oxygen species enhancing the susceptibility to oxidative stress by inducing up- and down-regulation of non-enzymatic and enzymatic profile studied in brain sub regions causing loss of their normal function which can consequently lead to deterioration of cell structure and death if copper deficiency is prolonged.

Serum trace element and amino acid profile in children with cerebral palsy

BACKGROUND

The existing data demonstrate that both trace elements and amino acids play a significant role in neurodevelopment and brain functioning. Certain studies have demonstrated alteration of micronutrient status in children with cerebral palsy, although multiple inconsistencies exist.

THE OBJECTIVE

of the present study was to assess serum trace element and mineral, as well as amino acid levels in children with cerebral palsy.

METHODS

71 children with cerebral palsy (39 boys and 32 girls, 5.7 ± 2.3 y.o.) and 84 healthy children (51 boys and 33 girls, 5.4 ± 2.3 y.o.) were enrolled in the present study. Serum trace element and mineral levels were assessed using inductively-coupled plasma mass-spectrometry (ICP-MS). Amino acid profile was evaluated by means of high-pressure liquid chromatography (HPLC).

RESULTS

Children with cerebral palsy are characterized by significantly lower Cu and Zn levels by 6% and 8%, whereas serum I concentration exceeded the control values by 7%. A tendency to increased serum Mn and Se levels was also observed in patients with cerebral palsy. Serum citrulline, leucine, tyrosine, and valine levels were 15 %, 23 %, 15 %, and 11 % lower than those in healthy controls. Nearly twofold lower levels of serum proline were accompanied by a 44 % elevation of hydroxyproline concentrations when compared to the control values. In multiple regression model serum I, Zn, and hydroxyproline levels were found to be independently associated with the presence of cerebral palsy. Correlation analysis demonstrated a significant correlation between Cu, Mn, Se, I, and Zn levels with hydroxyproline and citrulline concentrations.

CONCLUSION

The observed alterations in trace element and amino acid metabolism may contribute to neurological deterioration in cerebral palsy. However, the cross-sectional design of the study does not allow to estimate the causal trilateral relationships between cerebral palsy, altered trace element, and amino acid metabolism.

The status of chemical elements in the blood plasma of children with autism spectrum disorder in Tunisia: a case-control study

Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders defined by a deficit in social interactions and the presence of restricted and stereotypical behaviors or interests. The etiologies of autism remain mostly unknown. Many genetic and environmental factors have been suspected. Among these environmental factors, exposure to several chemical elements has been previously studied. The purpose of this study was to compare the levels of trace elements in the blood plasma of children with ASD with typically developed children (TDC). The participants in this study consisted of 89 children with ASD (14 girls and 74 boys) and 70 TD children (29 girls and 41 boys). The levels of 33 chemical elements have been analyzed by inductively coupled plasma spectrometry (ICP-MS). We detected significant differences in the levels of eight elements between the two groups, among which there were three rare earth elements (REEs): Eu, Pr, and Sc (p = 0.000, p = 0.023, and p < 0.001 respectively); four heavy metals: Bi, Tl, Ti, and V (p = 0.004, p < 0.001, p = 0.001, and p = 0.001 respectively); and one essential element: Cu (p = 0.043). Children with ASD had higher levels of Er, Pr, Sc, Bi, Tl, Ti, and V, and lower levels of Cu in comparison with the TD group. The children exposed to passive smoking had lower levels of lead (Pb) compared with children without exposure (p = 0.018). Four elements (Cr, Er, Dy, and Pr) were negatively correlated to the severity of ASD. The level of Cu was significantly associated with autistic children's behavior (p = 0.014). These results suggest that children with ASD might have abnormal plasma levels of certain chemical elements (including Er, Pr, Sc, Bi, Tl, Ti, and V, and Cu), and some of these elements might be associated with certain clinical features.

Maternal copper status and neuropsychological development in infants and preschool children

INTRODUCTION

Copper (Cu) is an essential element involved in biological processes; however, excessive Cu could be harmful because of its reactive nature. Very few studies have evaluated its potential neurotoxic effects. We aimed to evaluate the association between maternal Cu levels and children's neuropsychological development.

METHODS

Study subjects were mother-child pairs from the Spanish INMA (i.e. Childhood and Environment) Project. Cu was measured by inductively coupled plasma mass spectrometry in serum samples taken at the first trimester of pregnancy (2003-2005). Neuropsychological development was assessed using the Bayley Scales of Infant Development (BSID) at 12 months (n = 651) and the McCarthy Scales of Children's Abilities (MSCA) at 5 years of age (n = 490). Covariates were obtained by questionnaires during pregnancy and childhood. Multivariate linear and non-linear models were built in order to study the association between maternal Cu and child neuropsychological development.

RESULTS

The mean ± standard deviation of maternal Cu concentrations was 1606 ± 272 μg/L. In the multivariate analysis, a negative linear association was found between maternal Cu concentrations and both the BSID mental scale (beta = -0.051; 95% confidence intervals [CI]: -0.102, -0.001) and the MSCA verbal scale (beta = -0.044; 95%CI:-0.094, 0.006). Boys obtained poorer scores than girls, with increasing Cu at 12 months (interaction p-value = 0.040 for the mental scale and 0.074 for the psychomotor scale). This effect modification disappeared at 5 years of age. The association between Cu and the MSCA scores (verbal, perceptive performance, global memory and motor, general cognitive, and executive function scales) was negative for those children with lowest maternal iron concentrations (<938μg/L).

CONCLUSION

The Cu concentrations observed in our study were within the reference range established for healthy pregnant women in previous studies. The results of this study contribute to the body of scientific knowledge with important information on the possible neurotoxic capability of Cu during pregnancy.

Brain Nutrition: A Life Span Approach

Appraising success in meeting the world's nutritional needs has largely focused on infant mortality and anthropometric measurements with an emphasis on the first 1,000 days (conception to approximately age 2 years). This ignores the unique nutritional needs of the human brain. Although the intrauterine environment and the early postnatal years are important, equally critical periods follow during which the brain's intricate wiring is established for a lifetime of experience-driven remodeling. At the peak of this process during childhood, the human brain may account for 50% of the body's basal nutritional requirement. Thus, the consequences of proper nutritional management of the brain play out over a lifetime. Our motivation in preparing this review was to move the human brain into a more central position in the planning of nutritional programs. Here we review the macro- and micronutrient requirements of the human brain and how they are delivered, from conception to adulthood.

Micronutrients during pregnancy and child psychomotor development: Opposite effects of Zinc and Selenium

Studies on the impact of micronutrient levels during different pregnancy periods on child psychomotor functions are limited. The aim of this study was to evaluate the association between maternal plasma concentrations of selected micronutrients, such as: copper (Cu), zinc (Zn), selenium (Se), and child neuropsychological development. The study population consisted of 539 mother-child pairs from Polish Mother and Child Cohort (REPRO_PL). The micronutrient levels were measured in each trimester of pregnancy, at delivery and in the cord blood. Psychomotor development was assessed in children at the age of 1 and 2 years using the Bayley Scales of Infant and Toddler Development. The mean plasma Zn, Cu and Se concentrations in the 1st trimester of pregnancy were 0.91±0.27mg/l, 1.98±0.57mg/l and 48.35±10.54μg/l, respectively. There were no statistically significant associations between Cu levels and any of the analyzed domains of child development. A positive association was observed between Se level in the 1st trimester of pregnancy and child language and motor skills (β=0.18, p=0.03 and β=0.25, p=0.005, respectively) at one year of age. Motor score among one-year-old children decreased along with increasing Zn levels in the 1st trimester of pregnancy and in the cord blood (β=-12.07, p=0.003 and β=-6.51, p=0.03, respectively). A similar pattern was observed for the association between Zn level in the 1st trimester of pregnancy and language abilities at one year of age (β=-7.37, p=0.05). Prenatal Zn and Se status was associated with lower and higher child psychomotor abilities, respectively, within the first year of life. Further epidemiological and preclinical studies are necessary to confirm the associations between micronutrient levels and child development as well as to elucidate the underlying mechanisms of their effects.

Postnatal Migration of Cerebellar Interneurons

Due to its continuing development after birth, the cerebellum represents a unique model for studying the postnatal orchestration of interneuron migration. The combination of fluorescent labeling and ex/in vivo imaging revealed a cellular highway network within cerebellar cortical layers (the external granular layer, the molecular layer, the Purkinje cell layer, and the internal granular layer). During the first two postnatal weeks, saltatory movements, transient stop phases, cell-cell interaction/contact, and degradation of the extracellular matrix mark out the route of cerebellar interneurons, notably granule cells and basket/stellate cells, to their final location. In addition, cortical-layer specific regulatory factors such as neuropeptides (pituitary adenylate cyclase-activating polypeptide (PACAP), somatostatin) or proteins (tissue-type plasminogen activator (tPA), insulin growth factor-1 (IGF-1)) have been shown to inhibit or stimulate the migratory process of interneurons. These factors show further complexity because somatostatin, PACAP, or tPA have opposite or no effect on interneuron migration depending on which layer or cell type they act upon. External factors originating from environmental conditions (light stimuli, pollutants), nutrients or drug of abuse (alcohol) also alter normal cell migration, leading to cerebellar disorders.

The role of neuropathological markers in the interpretation of neuropsychiatric disorders: Focus on fetal and perinatal programming

The study of neuropathological markers in patients affected by mental/psychiatric disorders is relevant for the comprehension of the pathogenesis and the correlation with the clinical symptomatology. The neuropathology of Alzheimer's disease (AD) recognizes intraneuronal and extracellular neurofibrillary formation responsible for neuronal degeneration. Immunohistochemical studies discovered many interesting results for a better interpretation of the AD pathogenesis, while the "metal hypothesis" supports that metal ions might differentially influence the formation of amyloid aggregates. The most relevant pathological findings reported in schizophrenia originate from computer assisted tomography (CT), Magnetic Resonance Imaging (MRI) studies and Diffusion Tensor Imaging (DTI), suggesting the brain abnormalities involved in the pathophysiology of schizophrenia. The theory of fetal programming illustrates the epigenetic factors that may act during the intrauterine life on brain development, with relevant consequences on the susceptibility to develop AD or schizophrenia later in life. The neuropathological interpretation of AD and schizophrenia shows that the presence of severe neuropathological changes is not always associated with severe cognitive impairment. A better dialogue between psychiatrics and pathologists might help to halt insurgence and progression of neurodegenerative diseases.

Loss of divalent metal transporter 1 function promotes brain copper accumulation and increases impulsivity

The divalent metal transporter 1 (DMT1) is a major iron transporter required for iron absorption and erythropoiesis. Loss of DMT1 function results in microcytic anemia. While iron plays an important role in neural function, the behavioral consequences of DMT1 deficiency are largely unexplored. The goal of this study was to define the neurobehavioral and neurochemical phenotypes of homozygous Belgrade (b/b) rats that carry DMT1 mutation and explore potential mechanisms of these phenotypes. The b/b rats (11-12 weeks old) and their healthy littermate heterozygous (+/b) Belgrade rats were subject to elevated plus maze tasks. The b/b rats spent more time in open arms, entered open arms more frequently and traveled more distance in the maze than +/b controls, suggesting increased impulsivity. Impaired emotional behavior was associated with down-regulation of GABA in the hippocampus in b/b rats. Also, b/b rats showed increased GABAA receptor α1 and GABA transporter, indicating altered GABAergic function. Furthermore, metal analysis revealed that b/b rats have decreased total iron, but normal non-heme iron, in the brain. Interestingly, b/b rats exhibited unusually high copper levels in most brain regions, including striatum and hippocampus. Quantitative PCR analysis showed that both copper importer copper transporter 1 and exporter copper-transporting ATPase 1 were up-regulated in the hippocampus from b/b rats. Finally, b/b rats exhibited increased 8-isoprostane levels and decreased glutathione/glutathione disulfide ratio in the hippocampus, reflecting elevated oxidative stress. Combined, our results suggest that copper loading in DMT1 deficiency could induce oxidative stress and impair GABA metabolism, which promote impulsivity-like behavior. Iron-copper model: Mutations in the divalent metal transporter 1 (DMT1) decrease body iron status and up-regulate copper absorption, which leads to copper loading in the brain and consequently increases metal-induced oxidative stress. This event disrupts GABAergic neurotransmission and promotes impulsivity-like behavior. Our model provides better understanding of physiological risks associated with imbalanced metal metabolism in mental function and, more specifically, the interactions with GABA and redox control in the treatment of emotional disorders.

Copper delivery to the CNS by CuATSM effectively treats motor neuron disease in SOD(G93A) mice co-expressing the Copper-Chaperone-for-SOD

Over-expression of mutant copper, zinc superoxide dismutase (SOD) in mice induces ALS and has become the most widely used model of neurodegeneration. However, no pharmaceutical agent in 20 years has extended lifespan by more than a few weeks. The Copper-Chaperone-for-SOD (CCS) protein completes the maturation of SOD by inserting copper, but paradoxically human CCS causes mice co-expressing mutant SOD to die within two weeks of birth. Hypothesizing that co-expression of CCS created copper deficiency in spinal cord, we treated these pups with the PET-imaging agent CuATSM, which is known to deliver copper into the CNS within minutes. CuATSM prevented the early mortality of CCSxSOD mice, while markedly increasing Cu, Zn SOD protein in their ventral spinal cord. Remarkably, continued treatment with CuATSM extended the survival of these mice by an average of 18 months. When CuATSM treatment was stopped, these mice developed ALS-related symptoms and died within 3 months. Restoring CuATSM treatment could rescue these mice after they became symptomatic, providing a means to start and stop disease progression. All ALS patients also express human CCS, raising the hope that familial SOD ALS patients could respond to CuATSM treatment similarly to the CCSxSOD mice.

Prenatal molybdenum exposure and infant neurodevelopment in Mexican children

OBJECTIVE

To evaluate the association between prenatal exposure to molybdenum (Mo) and infant neurodevelopment during the first 30 months of life.

METHODS

We selected a random sample of 147 children who participated in a prospective cohort study in four municipalities in the State of Morelos, Mexico. The children were the products of uncomplicated pregnancies with no perinatal asphyxia, with a weight of ≥2 kg at birth, and whose mothers had no history of chronic illnesses. These women were monitored before, during, and after the pregnancy. For each of these children a maternal urine sample was available for at least one trimester of pregnancy, and urine Mo levels were determined by electrothermal atomic absorption spectrometry. Neurodevelopment was evaluated using the psychomotor (PDI) and mental development indices (MDI) of the Bayley scale. Association between prenatal exposure to Mo and infant neurodevelopment was estimated using generalized mixed effect models.

RESULTS

The average urinary concentrations of Mo adjusted for creatinine varied between 45.6 and 54.0 µg/g of creatinine at first and third trimester, respectively. For each doubling increase of Mo (μg/g creatinine) during the third trimester of pregnancy, we observed a significant reduction on PDI (β = -0.57 points; P = 0.03), and no effect on MDI (β = 0.07 points; P = 0.66).

DISCUSSION

As this is the first study that suggests a potential negative association between prenatal Mo exposure and infant neurodevelopment, these results require further confirmation.

Boron deprivation alters rat behaviour and brain mineral composition differently when fish oil instead of safflower oil is the diet fat source*

PRIMARY OBJECTIVE

To determine whether boron deprivation affects rat behaviour and whether behavioural responses to boron deprivation are modified by differing amounts of dietary long-chain omega-3 fatty acids.

RESEARCH DESIGN

Female rats were fed diets containing 0.1 mg (9 micromol)/kg boron in a factorial arrangement with dietary variables of supplemental boron at 0 and 3mg (278 micromol)/kg and fat sources of 75 g/kg safflower oil or 65 g/kg fish (menhaden) oil plus 10 g/kg linoleic acid. After 6 weeks, six females per treatment were bred. Dams and pups continued on their respective diets through gestation, lactation and after weaning. Between ages 6 and 20 weeks, behavioural tests were performed on 13-15 male offspring from three dams in each dietary treatment. The rats were euthanized at age 21 weeks for the collection of tissues and blood.

METHODS AND PROCEDURES

At ages 6 and 19 weeks, auditory startle was evaluated with an acoustic startle system and avoidance behaviour was evaluated by using an elevated plus maze. At ages 7 and 20 weeks, spontaneous behaviour activity was evaluated with a photobeam activity system. A brightness discrimination test was performed on the rats between age 15 and 16 weeks. Brain mineral composition was determined by coupled argon plasma atomic emission spectroscopy. Plasma total glutathione was determined by HPLC and total cholesterol and 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha) were determined by using commercially available kits.

MAIN OUTCOMES AND RESULTS

Boron-deficient rats were less active than boron-adequate rats when fed safflower oil based on reduced number, distance and time of horizontal movements, front entries, margin distance and vertical breaks and jumps in the spontaneous activity evaluation. Feeding fish oil instead of safflower oil attenuated the activity response to boron deprivation. In the plus maze evaluation, the behavioural reactivity of the boron-deficient rats fed fish oil was noticeably different than the other three treatments. They made more entries into both open and closed arms and the center area and thus visited more locations. The boron-deficient rats fed fish oil also exhibited the lowest copper and zinc and highest boron concentrations in brain and the highest plasma glutathione concentration. Both boron deprivation and safflower oil increased plasma 8-iso-PGF2alpha.

CONCLUSIONS

Both dietary boron and long-chain omega-3 fatty acids influence rat behaviour and brain composition and the influence of one these bioactive substances can be altered by changing the intake of the other. Brain mineral and plasma cholesterol, glutathione and 8-iso-PGF2alpha findings suggest that rat behaviour is affected by an interaction between boron and fish oil because both affect oxidative metabolism and act the cellular membrane level.

Effects of valerian consumption during pregnancy on cortical volume and the levels of zinc and copper in the brain tissue of mouse fetus

OBJECTIVE

The aim of the present study was to determine the effects of valerian (Valeriana officinalis) consumption in pregnancy on cortical volume and the levels of zinc and copper, two essential elements that affect brain development and function, in the brain tissues of mouse fetuses.

METHODS

Pregnant female mice were treated with either saline or 1.2 g/kg body weight valerian extract intraperitoneally daily on gestation days (GD) 7 to 17. On GD 20, mice were sacrificed and their fetuses were collected. Fetal brains were dissected, weighed and processed for histological analysis. The volume of cerebral cortex was estimated by the Cavalieri principle. The levels of zinc and copper in the brain tissues were measured by atomic absorption spectroscopy.

RESULTS

The results indicated that valerian consumption in pregnancy had no significant effect on brain weight, cerebral cortex volume and copper level in fetal brain. However,it significantly decreased the level of zinc in the brain (P<0.05).

CONCLUSION

Using valerian during midgestation do not have an adverse effect on cerebral cortex; however,it caused a significant decrease in zinc level in the fetal brain. This suggests that valerian use should be limited during pregnancy.

Maternofetal and neonatal copper requirements revealed by enterocyte-specific deletion of the Menkes disease protein

The essential requirement for copper in early development is dramatically illustrated by Menkes disease, a fatal neurodegenerative disorder of early childhood caused by loss-of-function mutations in the gene encoding the copper transporting ATPase ATP7A. In this study, we generated mice with enterocyte-specific knockout of the murine ATP7A gene (Atp7a) to test its importance in dietary copper acquisition. Although mice lacking Atp7a protein within intestinal enterocytes appeared normal at birth, they exhibited profound growth impairment and neurological deterioration as a consequence of copper deficiency, resulting in excessive mortality prior to weaning. Copper supplementation of lactating females or parenteral copper injection of the affected offspring markedly attenuated this rapid demise. Enterocyte-specific deletion of Atp7a in rescued pregnant females did not restrict embryogenesis; however, copper accumulation in the late-term fetus was severely reduced, resulting in early postnatal mortality. Taken together, these data demonstrate unique and specific requirements for enterocyte Atp7a in neonatal and maternofetal copper acquisition that are dependent on dietary copper availability, thus providing new insights into the mechanisms of gene-nutrient interaction essential for early human development.

Effects of a copper-deficient diet on the biochemistry, neural morphology and behavior of aged mice

Copper dyshomeostasis has been suggested as an aetiological risk factor for some neurodegenerative diseases, such as Alzheimer’s disease. However, the precise mechanism at the base of this involvement is still obscure. In this work, we show the effects of a copper-deficient diet in aged CD1 mice and the influence of such a diet on: a) the concentration of various metal ions (aluminium, copper, iron, calcium, zinc) in the main organs and in different brain areas; b) the alteration of metallothioneins I-II and tyrosine hydroxylase immunopositivity in the brain; c) behavioural tests (open field, pole, predatory aggression, and habituation/dishabituation smell tests). Our data suggested that the copper-deficiency was able to produce a sort of “domino effect” which altered the concentration of the other tested metal ions in the main organs as well as in the brain, without, however, significantly affecting the animal behaviour.

Impairment of interrelated iron- and copper homeostatic mechanisms in brain contributes to the pathogenesis of neurodegenerative disorders

Iron and copper are important co-factors for a number of enzymes in the brain, including enzymes involved in neurotransmitter synthesis and myelin formation. Both shortage and an excess of iron or copper will affect the brain. The transport of iron and copper into the brain from the circulation is strictly regulated, and concordantly protective barriers, i.e., the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier (BCB) have evolved to separate the brain environment from the circulation. The uptake mechanisms of the two metals interact. Both iron deficiency and overload lead to altered copper homeostasis in the brain. Similarly, changes in dietary copper affect the brain iron homeostasis. Moreover, the uptake routes of iron and copper overlap each other which affect the interplay between the concentrations of the two metals in the brain. The divalent metal transporter-1 (DMT1) is involved in the uptake of both iron and copper. Furthermore, copper is an essential co-factor in numerous proteins that are vital for iron homeostasis and affects the binding of iron-response proteins to iron-response elements in the mRNA of the transferrin receptor, DMT1, and ferroportin, all highly involved in iron transport. Iron and copper are mainly taken up at the BBB, but the BCB also plays a vital role in the homeostasis of the two metals, in terms of sequestering, uptake, and efflux of iron and copper from the brain. Inside the brain, iron and copper are taken up by neurons and glia cells that express various transporters.

Histopathological and biochemical findings of congenital copper deficiency: are these similar to those of caprine arthritis-encephalitis?

This study was done after identifying animals with a twisted carpal joint in goat herd. These included a kid goat walking on its articulus carpii and a newborn goat with a stiff leg. Necropsies of the diseased goats revealed swollen carpal joints that were twisted backwards. Arthritis was observed during microscopic examination of the carpal joints. Very low levels of eosinophil, leucocyte, and lymphocyte cell infiltration were found in the central nervous system and meninges. Serum copper levels were significantly decreased in most of the animals. All of these results led us to diagnose the animals with swayback disease.

Peptidylgycine α-amidating monooxygenase and copper: a gene-nutrient interaction critical to nervous system function

Peptidylgycine alpha-amidating monooxygenase (PAM), a highly conserved copper-dependent enzyme, is essential for the synthesis of all amidated neuropeptides. Biophysical studies revealed that the binding of copper to PAM affects its structure, and cell biological studies demonstrated that the endocytic trafficking of PAM was sensitive to copper. We review data indicating that genetic reduction of PAM expression and mild copper deficiency in mice cause similar alterations in several physiological functions known to be regulated by neuropeptides: thermal regulation, seizure sensitivity, and anxiety-like behavior.

Maternal iron supplementation attenuates the impact of perinatal copper deficiency but does not eliminate hypotriiodothyroninemia nor impaired sensorimotor development

Copper, iron and iodine/thyroid hormone (TH) deficiencies disrupt brain development. Neonatal Cu deficiency causes Fe deficiency and may impact thyroidal status. One purpose of these studies was to determine the impact of improved iron status following Cu deficiency by supplementing the diet with iron. Cu deficiency was produced in pregnant Holtzman [Experiment 1 (Exp. 1)] or Sprague-Dawley [Experiment 2 (Exp. 2)] rats using two different diets. In Exp. 2, dietary Fe content was increased from 35 to 75 mg/kg according to NRC guidelines for reproduction. Cu-deficient (CuD) Postnatal Day 24 (P24) rats from both experiments demonstrated lower hemoglobin, serum Fe and serum triiodothyronine (T3) concentrations. However, brain Fe was lower only in CuD P24 rats in Exp. 1. Hemoglobin and serum Fe were higher in Cu adequate (CuA) P24 rats from Exp. 2 compared to Exp. 1. Cu- and TH-deficient rats from Exp. 2 exhibited a similar sensorimotor functional deficit following 3 months of repletion. Results suggest that Cu deficiency may impact TH status independent of its impact on iron biology. Further research is needed to clarify the individual roles for Cu, Fe and TH in brain development.

Perinatal iron and copper deficiencies alter neonatal rat circulating and brain thyroid hormone concentrations

Copper (Cu), iron (Fe), and iodine/thyroid hormone (TH) deficiencies lead to similar defects in late brain development, suggesting that these micronutrient deficiencies share a common mechanism contributing to the observed derangements. Previous studies in rodents (postweanling and adult) and humans (adolescent and adult) indicate that Cu and Fe deficiencies affect the hypothalamic-pituitary-thyroid axis, leading to altered TH status. Importantly, however, relationships between Fe and Cu deficiencies and thyroidal status have not been assessed in the most vulnerable population, the developing fetus/neonate. We hypothesized that Cu and Fe deficiencies reduce circulating and brain TH levels during development, contributing to the defects in brain development associated with these deficiencies. To test this hypothesis, pregnant rat dams were rendered Cu deficient (CuD), FeD, or TH deficient from early gestation through weaning. Serum thyroxine (T(4)) and triiodothyronine (T(3)), and brain T(3) levels, were subsequently measured in postnatal d 12 (P12) pups. Cu deficiency reduced serum total T(3) by 48%, serum total T(4) by 21%, and whole-brain T(3) by 10% at P12. Fe deficiency reduced serum total T(3) by 43%, serum total T(4) by 67%, and whole-brain T(3) by 25% at P12. Brain mRNA analysis revealed that expression of several TH-responsive genes were altered in CuD or FeD neonates, suggesting that reduced TH concentrations were sensed by the FeD and CuD neonatal brain. These results indicate that at least some of the brain defects associated with neonatal Fe and Cu deficiencies are mediated through reductions in circulating and brain TH levels.

Perinatal copper deficiency alters rat cerebellar purkinje cell size and distribution

Copper is required for activity of several key enzymes and for optimal mammalian development, especially within the central nervous system. Copper-deficient (CuD) animals are visibly ataxic, and previous studies in rats have demonstrated impaired motor function through behavioral experiments consistent with altered cerebellar development. Perinatal copper deficiency was produced in Holtzman rat dams by restricting dietary copper during the last two thirds of gestation and lactation. Male offspring were evaluated at postnatal day 25. Compared to cerebella from copper-adequate pups, the CuD pups had larger Purkinje cell (PC) size and irregularities in the Purkinje cell monolayer. These results suggest that the ataxic behavioral phenotype of CuD rats may result from disrupted inhibitory pathways in the cerebellum. A similar PC phenotype is seen in Menkes disease and in mottled mouse mutants with genetic copper deficiency, suggesting that copper deficiency and not just specific loss of ATP7A function is responsible.

Influence of copper on early development: prenatal and postnatal considerations

Copper (Cu) is an essential nutrient whose requirement is increased during pregnancy and lactation. These represent times of critical growth and development, and the fetus and neonate are particularly vulnerable to deficiencies of this nutrient. Genetic mutations that predispose the offspring to inadequate stores of Cu can be life threatening as is observed in children with Menkes disease. During the last decade, severe Cu deficiency, once thought to be a rare condition, has been reported in the literature at an increasing frequency. Secondary Cu deficiencies can be induced by a variety of ways such as excessive zinc or iron intake, certain drugs, and bariatric surgery. Premature and low birth weight infants can be born with low Cu stores. A number of mechanisms can contribute to the teratogenicity of Cu including decreased activity of select cuproenzymes, increased oxidative stress, decreased nitric oxide availability, altered iron metabolism, abnormal extracellular matrix protein crosslinking, decreased angiogenesis and altered cell signaling among others. The brain, heart, and vessels as well as tissues such as lung, skin and hair, and systems including the skeletal, immune, and blood systems, are negatively affected by suboptimal Cu during development. Additionally, persistent structural, biochemical, and functional adverse effects in the offspring are noted even when Cu supplementation is initiated after birth, supporting the concept that adequate Cu nutriture during pregnancy and lactation is critical for normal development. Although Cu-containing IUDs are an effective method for increasing intrauterine Cu concentrations and for reducing the risk of pregnancy, high amounts of dietary Cu are not thought to represent a direct developmental risk.

The plausibility of maternal nutritional status being a contributing factor to the risk for fetal alcohol spectrum disorders: the potential influence of zinc status as an example

There is increasing evidence that human pregnancy outcome can be significantly compromised by suboptimal maternal nutritional status. Poor diet results in a maternal-fetal environment in which the teratogenicity of other insults such as alcohol might be amplified. As an example, there is evidence that zinc (Zn) can interact with maternal alcohol exposure to influence the risk for fetal alcohol spectrum disorders (FASD). Studies with experimental animals have shown that the teratogenicity of alcohol is increased under conditions of Zn deficiency, whereas its teratogenicity is lessened when animals are given Zn-supplemented diets or Zn injections before the alcohol exposure. Alcohol can precipitate an acute-phase response, resulting in a subsequent increase in maternal liver metallothionein, which can sequester Zn and lead to decreased Zn transfer to the fetus. Importantly, the teratogenicity of acute alcohol exposure is reduced in metallothionein knockout mice, which can have improved Zn transfer to the conceptus relative to wild-type mice. Consistent with the above, Zn status has been reported to be low in alcoholic women at delivery. Preliminary data from two basic science and clinical nutritional studies that are ongoing as part of the international Collaborative Initiative on Fetal Alcohol Spectrum Disorders support the potential role of Zn, among other nutritional factors, relative to risk for FASD. Importantly, the nutrient levels being examined in these studies are relevant to general clinical populations and represent suboptimal levels rather than severe deficiencies. These data suggest that moderate deficiencies in single nutrients can act as permissive factors for FASD, and that adequate nutritional status or intervention through supplementation may provide protection from some of the adverse effects of prenatal alcohol exposure.

Effects of early malnutrition on mental system, metabolic syndrome, immunity and the gastrointestinal tract

The notion of how malnutrition early in life affects ontogenesis has evolved considerably since the mid-1960s. Since then, there have been many studies on the effects of early malnutrition. Nutritional and metabolic exposure during critical periods in early human and animal development may have long-term programming effects in adulthood. This is supported by evidence from epidemiological studies, numerous animal models and clinical intervention trials. In this paper, we review the effects of early malnutrition on cognitive function, metabolic syndrome, immunity and the gastrointestinal tract, as well as possible underlying mechanisms, and consider diarrhoeal disease and poor cognitive function as examples for understanding the interrelation of the harmful effects caused by early malnutrition. Previous studies on early malnutrition have mainly concentrated on humans and rats. Therefore, the main aim of the present review was to give animal scientists a clear understanding of the harmful effects of early malnutrition on animal growth and animal production, and to help identify appropriate feeding techniques to prevent early malnutrition.

Interactions of peptide amidation and copper: novel biomarkers and mechanisms of neural dysfunction

Mammalian genomes encode only a small number of cuproenzymes. The many genes involved in coordinating copper uptake, distribution, storage and efflux make gene/nutrient interactions especially important for these cuproenzymes. Copper deficiency and copper excess both disrupt neural function. Using mice heterozygous for peptidylglycine alpha-amidating monooxygenase (PAM), a cuproenzyme essential for the synthesis of many neuropeptides, we identified alterations in anxiety-like behavior, thermoregulation and seizure sensitivity. Dietary copper supplementation reversed a subset of these deficits. Wildtype mice maintained on a marginally copper-deficient diet exhibited some of the same deficits observed in PAM(+/-) mice and displayed alterations in PAM metabolism. Altered copper homeostasis in PAM(+/-) mice suggested a role for PAM in the cell type specific regulation of copper metabolism. Physiological functions sensitive to genetic limitations of PAM that are reversed by supplemental copper and mimicked by copper deficiency may serve as indicators of marginal copper deficiency.

Copper deficiency alters the neurochemical profile of developing rat brain

Copper deficiency is associated with impaired brain development and mitochondrial dysfunction. Perinatal copper deficiency was produced in Holtzman rats. In vivo proton NMR spectroscopy was used to quantify 18 cerebellar and hippocampal metabolites on postnatal day 21 (P21). Copper status was evaluated in male copper-adequate (CuA) and copper-deficient (CuD) brothers at P19 and at P23, 2 days following NMR experiments, by metal and in vitro metabolite data. Compared to CuA pups, CuD pups had lower ascorbate concentration in both brain regions, confirming prior HPLC data. Both regions of CuD rats also had lower N-acetylaspartate levels consistent with delayed development or impaired mitochondrial function similar to prior work demonstrating elevated lactate and citrate. For other metabolites, the P21 neurochemical profile of CuD rats was remarkably similar to CuA rats but uniquely different from iron-deficient or chronic hypoxia models. Further research is needed to determine the neurochemical consequences of copper deficiency.

Augmented cerebellar lactate in copper deficient rat pups originates from both blood and cerebellum

Copper (Cu) is essential for proper brain development, particularly the cerebellum, and functions as a cofactor for enzymes including mitochondrial cytochrome c oxidase (CCO). Cu deficiency severely limits CCO activity. Augmented lactate in brain of Cu deficient (Cu-) humans and cerebella of Cu- rats is though to originate from impaired mitochondria. However, brain lactate may also originate from elevated blood lactate. The hypothesis that cerebellar lactate originates from elevated blood lactate in Cu- rat pups was tested. Analysis of Cu- and Cu adequate (Cu+) rat pups (experiment I) revealed blood lactate was elevated in Cu- rat pups and cerebellar lactate levels were closely correlated to blood lactate concentration. A second rat experiment (experiment II) assessed Cu- cerebellar lactate without the confounding factor of elevated blood lactate. Blood lactate levels of Cu- rat pups in experiment II were equal to those of controls; however, Cu- cerebellar lactate was still elevated, suggesting mitochondrial impairment by Cu deficiency. Treatment of rat pups with dichloroacetate (DCA), an activator of mitochondrial pyruvate dehydrogenase complex (PDC), lowered Cu- cerebellar lactate to control levels suggesting PDC inhibition is a site of mitochondrial impairment in Cu- cerebella. Results suggest Cu- cerebellar lactate originates from blood and cerebellum.

Iron and copper, and their interactions during development

During development, the fetus is entirely dependent on the mother for its nutrient requirements. Subsequently, it is a period when both are vulnerable to changes in dietary supply, especially of those nutrients that are marginal under normal circumstances. In developed countries, this applies mainly to micronutrients. Even now, iron deficiency is a common disorder, especially in pregnancy. Similarly, copper intake in the U.K. population is rarely above adequate levels. It is now becoming clear that nutrient deficiencies during pregnancy can result in problems for the offspring, in both the short- and long-term. Early studies showed that lambs born to mothers on copper-deficient pastures developed 'swayback', with neurological and muscular symptoms that could not be reversed by postnatal supplementation. Our own findings have shown that prenatal iron deficiency results in increased postnatal blood pressure, even though the offspring have normal dietary iron levels from birth. These observations emphasize the importance of iron and copper in growth and development. Complicating the situation further is the fact that copper and iron are known to interact with each other in many ways, including absorption and intracellular transport. However, their interactions during the pregnancy appear to be more complex than during the non-pregnant state. In the present review, we examine the importance of these metals and their interactions, the consequences, both short- and long-term, of deficiency and consider some possible mechanisms whereby these effects may be generated.

Iron injection restores brain iron and hemoglobin deficits in perinatal copper-deficient rats

Copper (Cu) deficiency during perinatal development in rats is associated with anemia, lower plasma iron (Fe), and brain Fe. Experiments were conducted to inject Fe dextran into Cu-deficient (Cu-) rat pups to attempt to reverse these conditions. Previous work with older Cu- rats did not reverse anemia following Fe injection. Dams began Cu-adequate (Cu+) or Cu- dietary treatments starting at embryonic d 7 and lasting through weaning. In Expt. 1, pups from each dietary treatment were given a single dose of Fe, 20 mg Fe/kg, or saline (S) at postnatal d 11 (P11). Plasma Fe and hemoglobin were higher in the Fe-injected groups at P13. Brain Fe deficit and brain transferrin receptor enhancement were eliminated in the Cu- group injected with Fe compared with Cu-S pups, supporting an association between low plasma Fe and low brain Fe. In Expt. 2, Fe treatment was increased to 45 mg Fe/kg. Four injections were given between P5 and P18 (total dose, 5-7 mg Fe). At P20, Fe concentrations in 4 brain regions (cortex, cerebellum, medulla/pons, and hypothalamus) generally were higher in all groups than in Cu-S pups. At P25, impaired vibrissae-elicited foot placement was evident in Cu-S rats and was not improved by Fe injection. However, at P26, the brain Fe deficit in Cu-S pups was eliminated by Fe injection. Fe injections in Cu- pups raised plasma Fe, brain Fe, and hemoglobin but did not reverse low cytochrome c oxidase or abnormal striatal behavior.

Copper deficiency results in AMP-activated protein kinase activation and acetylCoA carboxylase phosphorylation in rat cerebellum

Copper (Cu) deficiency impairs cerebellar development including biosynthetic processes like myelination and synaptogenesis. The activity of cerebellar mitochondrial cuproenzyme cytochrome c oxidase is markedly lower in Cu deficient rat pups and is accompanied by higher lactate levels indicating mitochondrial inhibition. Cu deficiency impaired energy metabolism is thought to contribute to developmental delays, but specific mechanisms linking these phenomena have remained unexplored. AMP-activated protein kinase (AMPK) is a cellular energy sensor that is activated during mitochondrial inhibition and shuts down biosynthetic processes to help conserve cellular ATP levels. Activated AMPK phosphorylates and inhibits acetylCoA carboxylase (ACC), the first enzyme in fatty acid biosynthesis. We hypothesize that AMPK is activated and ACC inhibited in Cu deficient cerebella. Perinatal copper deficiency was studied in young rats in rapidly frozen cerebella. Compared to copper-adequate (Cu+) pups, copper-deficient (Cu-) pups were hypothermic, had lower brain copper levels and markedly higher cerebellar lactate. Concentration of phosphorylated AMPK (pAMPK), indicating AMPK activation, was robustly higher in Cu- cerebella of rat pups at two ages and in two separate experiments. Compared to Cu+ cerebella, pACC content was significantly higher in all Cu- samples. Mechanisms leading to AMPK activation remain elusive. Higher AMP/ATP ratios and increased reactive nitrogen species (RNS) can lead to AMPK activation. ATP and AMP concentrations were unaltered and nitric oxide metabolites and 3-nitrotyrosine peptide levels remained unchanged in Cu- cerebella. AMPK activation may explain how ATP levels can be maintained even with a severe mitochondrial loss of CCO function.

Low nitric oxide: a key factor underlying copper-deficiency teratogenicity

Copper (Cu)-deficiency-induced teratogenicity is characterized by major cardiac, brain, and vascular anomalies; however, the underlying mechanisms are poorly understood. Cu deficiency decreases superoxide dismutase activity and increases superoxide anions, which can interact with nitric oxide (NO), reducing the NO pool size. Given the role of NO as a developmental signaling molecule, we tested the hypothesis that low NO levels, secondary to Cu deficiency, represent a developmental challenge. Gestation day 8.5 embryos from Cu-adequate (Cu+) or Cu-deficient (Cu-) dams were cultured for 48 h in Cu+ or Cu- medium, respectively. We report that NO levels were low in conditioned medium from Cu-/Cu- embryos and yolk sacs, compared to Cu+/Cu+ controls under basal conditions and with NO synthase (NOS) agonists. The low NO production was associated with low endothelial NOS phosphorylation at serine 1177 and cyclic guanosine-3',5'-monophosphate (cGMP) concentrations in the Cu-/Cu- group. The altered NO levels in Cu-deficient embryos are functionally significant, as the administration of the NO donor DETA/NONOate increased cGMP and ameliorated embryo and yolk sac abnormalities. These data support the concept that Cu deficiency limits NO availability and alters NO-dependent signaling, which contributes to abnormal embryo and yolk sac development.

Rodent brain and heart catecholamine levels are altered by different models of copper deficiency

Limiting dopamine beta-monooxygenase results in lower norepinephrine (NE) and higher dopamine (DA) concentrations in copper-deficient Cu- tissues compared to copper-adequate Cu+ tissues. Mice and rat offspring were compared to determine the effect of differences in dietary copper Cu deficiency started during gestation or lactation on catecholamine, NE and DA, content in brain and heart. Holtzman rat and Hsd:ICR (CD-1) outbred albino mouse dams were fed a Cu- diet and drank deionized water or Cu supplemented water. Offspring were sampled at time points between postnatal ages 12 and 27. For both rat and mouse Cu- tissue, NE and DA changes were greater at later ages. Though Cu restriction began earlier in rats than mice in the gestational model, brain NE reduction was more severe in Cu- mice than Cu- rats. Cardiac NE reduction was similar in Cu- rodents in the gestation models. In the lactation model, mouse catecholamines were altered more than rat catecholamines. Furthermore, following lactational Cu deficiency Cu- mice were anemic and exhibited cardiac hypertrophy, Cu- rats displayed neither phenotype. Within a species, changes were more severe and proportional to the length of Cu deprivation. Lactational Cu deficiency in mice had greater consequences than in rats.

Milk ceruloplasmin is a valuable source of nutrient copper ions for mammalian newborns

This research focuses on the role of milk ceruloplasmin (Cp), the main extracellular copper-containing protein of vertebrates, as a source of copper for newborns. In the first part of the study, Cp concentration and Cp-associated copper were measured in human skimmed milk at the 1st and the 5th days postpartum. It was shown that most of the copper was associated with Cp and that the decrease in copper concentration during lactation was related to the drop of Cp levels. The following in vivo experiments demonstrated that milk [(125)I]Cp per os administered to 6-day-old rats (embryonic-type copper metabolism) was transported into their bloodstream. The electrophoretic mobility and relative molecular weight of [(125)I]Cp transferred through the cellular barrier remained unaltered. However, 22-day-old rats (adult-type copper metabolism) digested the administered milk [(125)I]Cp completely. In the final part of the study, newborn rats were fed with baby formula for 8d. It was found that these rats switched their copper metabolism from embryonic type to adult type earlier than their littermates fed by dams. Activation of Cp gene expression in the liver, increased Cp and copper concentrations in the blood, and reduced copper content of the liver were observed in the rats fed with baby formula. In the brain, no copper concentration change was observed, but Cp and copper concentrations were dramatically increased in the cerebrospinal fluid. The role of milk Cp as a source of copper adapted to embryonic-type copper metabolism is discussed.

Copper, oxidative stress, and human health

Copper (Cu), a redox active metal, is an essential nutrient for all species studied to date. During the past decade, there has been increasing interest in the concept that marginal deficits of this element can contribute to the development and progression of a number of disease states including cardiovascular disease and diabetes. Deficits of this nutrient during pregnancy can result in gross structural malformations in the conceptus, and persistent neurological and immunological abnormalities in the offspring. Excessive amounts of Cu in the body can also pose a risk. Acute Cu toxicity can result in a number of pathologies, and in severe cases, death. Chronic Cu toxicity can result in liver disease and severe neurological defects. The concept that elevated ceruloplasmin is a risk factor for certain diseases is discussed. In this paper, we will review recent literature on the potential causes of Cu deficiency and Cu toxicity, and the pathological consequences associated with the above. Finally, we will review some of the potential biochemical lesions that might underlie these pathologies. Given that oxidative stress is a characteristic of Cu deficiency, the role of Cu in the oxidative defense system will receive special attention. The concept that excess Cu may be a precipitating factor in Alzheimer's disease is discussed.

L-threo 3,4-dihydroxyphenylserine treatment during mouse perinatal and rat postnatal development does not alter the impact of dietary copper deficiency

Dietary copper (Cu) deficiency was induced perinatally in Swiss Albino mice and postnatally in male Holtzman rats to investigate the effect of L-threo 3,4-dihydroxyphenylserine (DOPS) on pup survival and catecholamine levels in a 2 x 2 factorial design. Mouse dams were placed on one of four treatments 14 days after mating and rats at postnatal day 19 (P19). Treatments were Cu-adequate (Cu + ) and Cu-deficient (Cu - ) diets with or without DOPS (1 mg/ml) in the drinking water. Mouse pups were killed at P14 and rats at P49. Mortality in Cu - pups was 46% and not significantly improved by DOPS, 39%. A repeat study with mice adding ascorbic acid in the water with DOPS showed no improvement. Compared to Cu + animals, Cu - animals were smaller, anemic and had a 92% reduction in liver Cu. DOPS treatment made no improvement to and in some cases exacerbated the Cu deficiency. Catecholamine levels measured in heart and brain by LCEC showed decreased NE levels and increased DA levels in Cu - animals compared to controls. DOPS treatment did not alter this pattern. Although DOPS was present in treated animal's tissues, survival in mice and catecholamine levels in mice and rats were not altered by the 1 mg/ml dose of DOPS.

Rat brain iron concentration is lower following perinatal copper deficiency

Experiments performed with Holtzman rats demonstrated that brain iron (Fe) was lower by postnatal day 13 (P13) in pups born and nursed by dams that began copper-deficient (-Cu) treatment at embryonic day 7. Transcardial perfusion of P24-P26 males and females to remove blood Fe contamination revealed that brain Fe was still 20% lower in -Cu than +Cu rats. Estimated blood content of brain for -Cu rats was greater than for +Cu rats; for all groups, values ranged between 0.43 and 1.03%. Using group-specific data and regression analyses, r = 0.99, relating blood Fe to hemoglobin, brain Fe in non-perfused rats in a replicate study was lower by 33% at P13 and 39% at P24 in -Cu rats. Brain extracts from these rats and from P50 rats from a post-weaning model were compared by immunoblotting for transferrin receptor (TfR1). P24 brain -Cu/+Cu TfR1 was 3.08, suggesting that brains of -Cu rats were indeed Fe deficient. This ratio in P13 rats was 1.44, p < 0.05. No change in P50 -Cu rat brain TfR1 or Fe content was detected despite a 50% reduction in plasma Fe. The results suggest that brain Fe accumulation depends on adequate Cu nutriture during perinatal development.