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 macular mouse is an animal model of Menkes disease. The neurological degeneration is caused by decreased cuproenzymes activity, such as cytochrome c oxidase (CCO), associated with copper deficiency in the brain. We investigated the age-related changes in copper concentration and CCO activity in the brain of macular mice which were given a single injection of cupric on postnatal day 7. The copper concentration in the brain of macular mice was always about 40% of that of the age-matched controls. However, the copper concentration of both macular and control mice increased with age gradually. The CCO activity in the brain of macular mice was significantly lower than that of controls at the age of 8 days. However the activity in macular mice increased with growth and reached a level equal to the controls at 180 days. These results suggest that the improvement of CCO activity in the brain of macular mice is due to the brain copper concentration which increased with age. Therefore, parenteral administration of copper is recommended especially during infancy in patients with Menkes disease.
 ...
PMID:Changes of copper level and cytochrome c oxidase activity in the macular mouse with age. 165 7

We present 64Cu uptake studies in cultured muscle cells from a one-year-old patient with Menkes' disease. The cultured muscle cells from the patient showed a five-fold higher 64Cu uptake than control muscle cells. Copper uptake in muscle cells was of the same magnitude as that found in fibroblasts from the patient and also from other Menkes' patients. The copper content of a muscle biopsy from the patient was twice that of a control biopsy. The enhanced uptake is probably copper specific, since zinc uptake was unaltered in both muscle cells and fibroblasts from the patient. Cytochrome c oxidase in the muscle of the patient was reduced to one-third of the value for controls, which is in agreement with the hypothesis that in Menkes' disease copper accumulates in a biologically non-active form. However, in cultured muscle cells and fibroblasts from the patient the cytochrome c oxidase activity was in the normal range, probably because of the relatively large amount of copper already available in the culture medium.
 ...
PMID:Muscle cell cultures in Menkes' disease: copper accumulation in myotubes. 216 83

Brain mitochondrial enzyme activities were examined in 15-day-old suckling mice which were daily injected with D-penicillamine (DP), a chelating agent of copper. Newborn mice treated with DP (1 g/kg/day) showed retarded weight gain, hyperelasticity of skin, and a bizarre forelimb posture with subcutaneous edema on experimental day (ED) 7. Paraparesis or dragging of the hindlimbs was observed by ED 15. Brain copper contents of DP-treated mice decreased to 34% of the controls of ED 15. Cytochrome c oxidase activity (complex IV) in the brain showed 51% decrease of the controls, on the contrary, rotenone-sensitive NADH cytochrome c reductase (complex I + III) and succinate cytochrome c reductase (complex II + III) were normal. Histochemistry of cytochrome c oxidase in the cerebellum of DP-treated mice disclosed diffuse reduction of staining, especially in Purkinje cells. These data show that DP-induced copper deficiency in the brain subsequently disturbs mitochondrial electron transport system, selectively cytochrome c oxidase activity. This seems to be a useful animal model not only for Menkes' kinky hair disease but also for mitochondrial encephalomyopathy.
 ...
PMID:D-penicillamine-induced copper deficiency in suckling mice: neurological abnormalities and brain mitochondrial enzyme activities. 217 57

The wet weight, copper content, mitochondrial electron-transfer complexes and 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) were measured in various organs including brain, liver, kidney, and heart in macular mutant mice which are considered to be an appropriate model for human Menkes kinky hair disease (MKHD). Copper contents were decreased markedly in liver, brain, and heart. However a significant increase was noted in kidney, suggesting a disproportionate distribution of copper contents in each organ in this mutant mouse. Regarding mitochondrial electron-transfer complexes, only cytochrome c oxidase, a copper dependent enzyme, was found to be decreased in heart and brain. This alteration in the brain was already demonstrated at 2 days. CNPase was not decreased in its activity at 7 days, but decreased at 14 days, supporting progressive demyelination. These results suggested that this mutant mouse would be a useful animal model for clarifying the pathogenesis in human MKHD.
 ...
PMID:[A pathophysiological study of macular mutant mouse as a model of human Menkes kinky hair disease. I. Copper contents and copper dependent enzyme activities in various organs]. 217 32

There are several known examples of mutations which influence copper homeostasis in humans and animals. Pleiotropic effects are observed when the mutant gene disturbs copper flux. In some cases, the mutation alters the level of a specific copper ligand (enzyme) and the clinical consequences are unique. The two most widely studied genetic maladies in humans are Menkes' and Wilson's diseases. Menkes' disease is an X-linked fatal disorder in which copper accumulates in some organs (intestine and kidney) and is low in others (liver and brain). Wilson's disease is an autosomal recessive disorder in which copper accumulates, if untreated, in liver and subsequently in brain and kidney. Pathophysiological consequences of copper deficiency and toxicity characterize these two disorders. Specific mutations of human cuproenzymes include overproduction of copper-zinc superoxide dismutase in Down's syndrome, absence of tyrosinase in albinism, hereditary mitochondrial myopathy due to reduction in cytochrome c oxidase, and altered lysyl oxidase in X-linked forms of cutis laxa and Ehlers-Danlos syndrome. Mutations altering copper metabolism are also known in animals. Several murine mutants have been studied. The most extensively investigated mutants are the mottled mice, in particular brindled mice, which have a mutation analogous to that of Menkes' disease. Another recently described murine mutation is toxic milk (tx) an autosomal recessive disorder that is characterized by copper accumulation in liver. Two other mutants, crinkled and quaking, were once thought to exhibit abnormal copper metabolism. Recent data has not confirmed this. A mutation in Bedlington terriers has been described which is very similar to Wilson's disease.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Genetic diseases of copper metabolism. 351 56

In a 4-year-old male with Menkes kinky hair disease (MKHD) treated with copper supplement therapy, reduced cytochrome a + a3 contents in liver was demonstrated to be 0.029 against 0.128 nmol/mg protein in the control. Cytochrome c oxidase activities in brain, liver, skeletal muscle, and heart were 47, 22, 54 and 59% of the control, respectively. The copper contents in brain and liver were decreased. In spite of increased serum levels of copper and ceruloplasmin, the decreased cytochrome c oxidase activities in various organs were not corrected by copper supplement therapy. A search for a therapeutic method which can normalize copper enzymes in brain and liver, would seem to be a prerequisite for the treatment of MKHD.
 ...
PMID:Cytochrome c oxidase deficiency in Menkes kinky hair disease. 632 7

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

Antibodies against subunits II and IV of cytochrome c oxidase (COX) and against complex III of the respiratory chain were used to study the expression of these proteins in the cerebellum, spinal cord, and other regions of the central nervous system in an autoptic case of Menkes' kinky hair disease (MKHD). We found a reduced expression of COX subunits in all examined areas whereas staining for complex III appeared normal. Immunostaining was altered in morphologically well-preserved neurons, suggesting that COX deficiency may have a pathogenetic role in the neuronal degeneration of MKHD.
 ...
PMID:Cytochrome C oxidase deficiency and neuronal involvement in Menkes' kinky hair disease: immunohistochemical study. 829 91

The hemizygote of the macular mutant mouse is clinically, biochemically and neuropathologically similar to a patient with Menkes kinky hair disease. The heterozygote of this mutant mouse was biochemically and neuropathologically examined. The copper content in the brain decreased in comparison with that in the normal littermate, although it was more than that in the hemizygote. In the Golgi study, abnormal Purkinje cells with somal sprouts, thick stem dendrites and dendritic focal swellings, which were seen in the hemizygote, were not observed in the heterozygote. Ultrastructurally, abnormal mitochondria were seen in the Purkinje cells in the anterior and middle cerebellar lobe of the heterozygote. Histochemically, cytochrome c oxidase activity decreased, especially at the anterior lobe in the cerebellar cortex of the heterozygote. This activity, as indicated by staining intensity, was in between that in the normal littermate and that in the hemizygote. The heterozygote did not show a mosaic pattern in the distribution of these neuropathological changes, although this mutant mouse shows x-linked recessive inheritance. Thus, our results lead to the conclusion that the neuropathological changes observed in this mutant mouse do not result directly from an abnormal gene in the Purkinje cell, but from the secondary effects of subsequent to presumptive copper deficiency.
 ...
PMID:Neuropathological study on cerebellum of macular mutant mouse heterozygote. 831 Jul 89

The brindled mottled mouse (Mobr), an animal model of the Menkes' copper deficiency syndrome, was used for the investigation of changes in respiratory flux control associated with cytochrome c oxidase deficiency in muscle. Enzymatic analysis of cardiac and skeletal muscles showed an approximately 2-fold decrease in cytochrome c oxidase activity of brindled mutants in both types of muscles as compared with controls. The activities of NADH-cytochrome c oxidoreductase (respiratory chain segment I-III) and succinate-cytochrome c oxidoreductase (segment II-III) were normal. Assessment of mitochondrial respiratory function was performed using chemically skinned musculus quadriceps or heart muscle fibers isolated from control and brindled mottled mice. In skeletal muscle, there was no difference found in maximal rates of respiration. In the Mobr hearts, this parameter was slightly lower than control. Alternately, the determination of flux control coefficients of cytochrome c oxidase performed by a step by step inhibition of respiration with increasing concentrations of azide or cyanide revealed significantly sharper inhibition curves for brindled mice than for control, indicating more than 2-fold elevated flux control coefficients of cytochrome c oxidase. This investigation proved essential in characterizing the metabolic effect of a cytochrome c oxidase deficiency. We conclude, therefore, that application of metabolic control analysis can be a valuable approach to study defects of mitochondrial oxidative phosphorylation.
 ...
PMID:Increase of flux control of cytochrome c oxidase in copper-deficient mottled brindled mice. 855 May 74


1 2 3 Next >>