Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022716 (Menkes)
 1,057 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of copper in maintaining normal neurological function has been examined in animals copper-deficient by dietary means, and in the genetic disorders of copper homeostasis -- Menkes' kinky-hair disease in humans and the mottled (Mo) mutants in the mouse. With the exception of the disorder in Mo mice, reduced myelination is a constant feature of these copper diseases but there is otherwise a lack of conformity in the structural defects produced in different species. Dietary copper-deficient animals show a reduction in noradrenaline and dopamine concentrations, together with a depressed tyrosine 3-monooxygenase activity (EC 1.14.16.2). Noradrenaline concentrations are also reduced in brain tissue of Mo mice and this reduction is associated with a decrease in the vivo activity of the copper metalloenzyme, dopamine beta-monooxygenase (EC 1.14.17.1). Many tissues contain potent inhibitors of dopamine beta-monooxygenase activity, and assays of this enzyme have utilized cupric ions to inactivate these inhibitors. The elevated in vitro activities of dopamine beta-monooxygenase obtained for both Mo brain and adrenal tissue may therefore reflect either a reduced inactivation of these endogenous inhibitors in the intact animal or the activation in vitro of apoenzyme. Concentrations of dopamine and tyrosine 3-monooxygenase are unchanged in Mo mice. The reduction in dopamine and tyrosine 3-monooxygenase activity in dietary copper-deficient animals may therefore reflect neuronal loss rather than reduced catalytic activity of the catecholamine biosynthetic pathway. The possible effects of depressed activities of cytochrome c oxidase (EC 1.9.3.1) and superoxide dismutase (EC 1.15.1.1) in the development of neurological dysfunction are also discussed, and attention is drawn to the possible significance of the elevated uptake of neutral amino acids, especially tyrosine and tryptophan, by Mo brain tissue.
 ...
PMID:Copper and neurological function. 690 87

The authors report a clinically typical case of trichopoliodystrophy (Menkes' disease) ; Neuropathological studies showed classical alterations, particularly irregular thickenings of Purkinje cell dendrites, and some less usual modifications : presence of an ectopic neuronal layer in the cerebellar molecular layer, suggestive of Obersteiner cells stopped in their progression ; normal appearance of myelin and elastic structures of systemic arteries. Ultrastructural studies showed some calcic concretions in mitochondria of hepatocytes and Purkinje cells, and lamellar structures in the cytoplasm of Purkinje cells, probably of ergastoplasmic origin. The activity of dopamine-beta-hydroxylase (DBH, or norepinephrine synthesising enzyme) and of phenylethanolamine - N-methyltransferase (PNMT, or epinephrine synthesising enzyme) was studied in 22 samples of brain stem. Activity was reduced in 3 samples, and increased in 4 : 6 of these 7 samples were from structures involved in cardiovascular and respiratory control. These results suggest the existence of a central vegetative neuropathy, which could explain the cardiovascular and respiratory disturbances sometimes reported in Menkes' disease ; but this neurochemical study gave no account of the sleep organization alterations of the patient.
 ...
PMID:[X - linked copper malabsorption (trichopoliodystrophy, Menkes' disease). Anatomical and neurochemical study of a case (author's transl)]. 724 52

In the 25 y since copper deficiency was first delineated in persons with Menkes syndrome, advances in our understanding of the clinical, biochemical, and molecular aspects of this rare disorder have surpassed progress in the design of effective therapies. In contrast with purely nutritional copper deficiency, in which copper replacement can be curative, the nature of the basic defect in Menkes syndrome suggests that corrective efforts are likely to be more complicated, a point supported by the cumulative literature on this topic as well as by emerging molecular data. In this paper, certain clinical, biochemical, and molecular aspects of copper histidine treatment in 25 Menkes syndrome patients at the National Institutes of Health are reviewed. The delineation of a distinctive neurochemical pattern in plasma and cerebrospinal fluid, reflecting deficiency of the copper enzyme dopamine beta-monooxygenase, is arguably the most important finding in the study of Menkes syndrome. This abnormal pattern has proven extremely reliable as a rapid diagnostic test, enabling early identification of affected infants--a fundamental requirement for improving clinical outcomes. Of 11 patients identified by prenatal or prompt postnatal testing and treated within the first 10 d of age, one walked at 14 mo of age and has normal neurodevelopment at age 3 y and another infant's early progress appears promising. However, five patients died in infancy and neurodevelopmental outcome was suboptimal in four others. Consideration of additional therapeutic strategies seems necessary, therefore, for most patients and families facing this troublesome form of copper deficiency.
 ...
PMID:Diagnosis and therapy of Menkes syndrome, a genetic form of copper deficiency. 958 47

The trace metal copper (Cu) plays an essential role in biology as a cofactor for many enzymes that include Cu, Zn superoxide dismutase, cytochrome oxidase, ceruloplasmin, lysyl oxidase, and dopamine beta-hydroxylase. Consequently, Cu transport at the cell surface and the delivery of Cu to intracellular compartments are critical events for a wide variety of biological processes. The components that orchestrate intracellular Cu trafficking and their roles in Cu homeostasis have been elucidated by the studies of model microorganisms and by the characterizations of molecular basis of Cu-related genetic diseases, including Menkes disease and Wilson disease. However, little is known about the mechanisms for Cu uptake at the plasma membrane and the consequences of defects in this process in mammals. Here, we show that the mouse Ctr1 gene encodes a component of the Cu transport machinery and that mice heterozygous for Ctr1 exhibit tissue-specific defects in copper accumulation and in the activities of copper-dependent enzymes. Mice completely deficient for Ctr1 exhibit profound growth and developmental defects and die in utero in mid-gestation. These results demonstrate a crucial role for Cu acquisition through the Ctr1 transporter for mammalian Cu homeostasis and embryonic development.
 ...
PMID:Essential role for mammalian copper transporter Ctr1 in copper homeostasis and embryonic development. 1139 Oct 5

Menkes disease is a disorder of copper transport that results in early death. Early therapy with parenteral copper-histidine has been shown to markedly improve outcomes. However, early diagnosis is difficult because patients are asymptomatic in early infancy. In Menkes disease, impaired activity of dopamine beta-hydroxylase, a copper-dependent enzyme, leads to increased urine ratios of homovanillic acid/vanillylmandelic acid (HVA/VMA). Urine HVA/VMA ratios ranged from 4.1 to 69.7 among 15 patients with Menkes disease, whereas only 0.18% of controls had ratios greater than 4.0. Thus, the urine HVA/VMA ratio is a useful screening method for Menkes disease.
 ...
PMID:Screening for Menkes disease using the urine HVA/VMA ratio. 1570 9

Menkes disease (MD) is a neurodegenerative disorder characterized by a copper deficiency in the brain. It is caused by the defective intestinal absorption of copper resulting from a deficiency of a copper-transporting ATPase, ATP7A. This gives rise to an accumulation of copper in the intestine. The copper deficiency in the brain of MD patients cannot be improved by copper injections, because the administered copper accumulates at the blood-brain barrier and is not transported across to the neurons. To resolve this problem, we investigated the effect of a combination therapy of copper and sodium diethyldithiocarbamate (DEDTC), a lypophilic chelator, in an animal model of MD, the macular mouse. Four-week-old macular mice treated with 50 mug of CuCl2 on the 7th day after birth were used. Experimental mice were given a subcutaneous injection of CuCl2 (4 microg) and an intraperitoneal injection of DEDTC (0.2 mg/g body weight) twice a week for 4 weeks and then sacrificed. Copper concentrations and cytochrome-c oxidase activity in the brains of treated mice were higher than those of control macular mice, which received only copper or saline. The ratios of brain noradrenaline to dopamine and of adrenaline to dopamine were also increased by the treatment, suggesting that the activity of dopamine beta-hydroxylase, a copper-dependent enzyme, was improved by the treatment. Liver and renal function tests showed no abnormalities in the treated mice, although copper concentrations in the kidneys of treated mice were higher than those of control macular mice. These results suggest that DEDTC facilitates the passage of copper across the blood-brain barrier and that the combination therapy of copper and DEDTC may be an effective treatment for the neurological disturbances suffered by patients with MD.
 ...
PMID:Effect of copper and diethyldithiocarbamate combination therapy on the macular mouse, an animal model of Menkes disease. 1643 90