Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.4.3.13 (lysyl oxidase)
 1,248 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Occipital horn syndrome (OHS; Ehlers-Danlos syndrome type IX) belongs to the category of the copper metabolism disorders and is at present being investigated biochemically as is Menkes disease. We report a case of OHS in a 34-year-old male, which we believe to be the first Japanese case. He had been noted to have psychomotor retardation since his early childhood and now presents severe psychomotor retardation and muscle atrophy. He shows characteristic facial appearance, hyperelasticity of the skin, joint subluxation and generalized muscular atrophy. Laboratory investigations revealed a low serum copper and ceruloplasmin level as well as intestinal non-absorption of copper. Radiologic imagings showed occipital exostoses and bladder diverticula. The activity of lysyl oxidase, a copper-dependent enzyme involved in cross-link formation in collagen, was decreased in a skin-biopsied specimen. Electronmicroscopic investigation of a muscle biopsy showed irregularity of the myofibrillar network and accumulation of the concentric laminated bodies in the subsarcolemmal regions.
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PMID:[Occipital horn syndrome (Ehlers-Danlos syndrome type IX) with severe psychomotor retardation and muscle atrophy--a first Japanese case]. 168 78

Effects of cadmium (Cd) on lysyl oxidase activity and copper (Cu) metabolism in bone were studied using Cu-deficient rats supplemented with Cu and/or Cd in a diet. When fed for 8 weeks on a diet containing 0.3 ppm or less Cu (-Cu diet), weanling rats revealed anemia, and markedly decreased plasma ceruloplasmin activity and serum Cu to less than 15% of normal level, showing features of Cu-deficiency. These rats were divided into four groups and refed for another 2 weeks on the following diets: Group I, -Cu diet; Group II, -Cu diet with 50 ppm Cd (+Cd diet); Group III, -Cu diet supplemented with 15 ppm Cu (+Cu diet); group IV, -Cu diet with both Cu and Cd (+Cu/+Cd diet). After 2 weeks, serum Cu levels of Groups I, II, III and IV were 1.8, 0.8, 78 and 74% of the normal control level (1.438 +/- 0.060 micrograms/ml), respectively. Concentrations of Cu in epi- and metaphyses of the control group, Groups I, II, III and IV were 1.45 +/- 0.20, 0.67 +/- 0.08, 0.76 +/- 0.12, 1.40 +/- 0.31 and 1.22 +/- 0.05 micrograms/g wet tissue, in that order. Concentrations of Cd in epi- and metaphysis increased in only Groups II and IV and were 0.15 +/- 0.03 and 0.18 +/- 0.01 micrograms/g wet tissue, respectively. Thus, having both Cd and Cu supplements in a diet did not inhibit each other's uptake into the tissue.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of dietary cadmium and/or copper on the bone lysyl oxidase in copper-deficient rats relative to the metabolism of copper in the bone. 197 55

The biochemistry of the essential trace element copper has been outlined. Following absorption, Cu(II) is transported by serum albumin and transcuprein to the liver where it is incorporated into the plasma Cu-protein, ceruloplasmin, or, possibly, stored as Cu-metallothionein or as superoxide dismutase. Ceruloplasmin is the long-term copper transporter and carries Cu(II) to the tissues for the biosynthesis of key Cu(II) enzymes, especially cytochrome c oxidase, lysyl oxidase and others. The production of copper enzymes raises many new questions about the metabolism of copper. Since ceruloplasmin is the centerpiece of copper metabolism and function, we conclude with more details on its chemistry and multifunctions. This Cu-protein of 132,000 daltons has now been totally sequenced and the copper-containing active sites located. Finally, we have proposed seven possible functions for ceruloplasmin, and there is now good evidence for the existence of ceruloplasmin receptors to expedite some of these functions.
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PMID:Perspectives on copper biochemistry. 300 68

Copper is required in trace amounts for many body functions. The prominent effects of Cu deficiency or Cu toxicosis differs greatly between animal species. Along with iron, Cu is necessary for the transfer of O2 via a cascade of enzymes so that energy may be available for vital body functions without overheating of the tissues through rapid oxidation. As a part of lysyl oxidase, Cu has an obligate function in the maturation of all connective tissue (including elastic tissue and bone) maintaining the form and integrity of all body organs. As a constituent of tyrosinase, Cu is involved in the formation of melanin, thus preventing albinism. Copper also is involved in the myelination of nerve fibers and the production of neutrophils, enkephalins, lipoproteins, and cholesterol. Copper must be properly sequestered to prevent toxicosis. Copper is stored primarily as metallothioneins and as superoxide dismutase and is transported primarily as ceruloplasmin or as low molecular weight proteins, peptides, and amino acids.
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PMID:Comparative metabolism of copper. 355 17

We have studied the effect of L-ascorbic acid (vitamin C) on copper metabolism using copper-deficient chicks and the activation of lysyl oxidase copper-dependent enzyme, to assess bioavailability of copper. When administered intraperitoneally with (or 75 minutes before) CuSO4, L-ascorbate significantly impared the effectiveness of copper to restore lysyl oxidase activity in deficient chicks. L-ascorbate given 75 minutes after CuSO4 (i.e., in the post-absorption period), however, produced a substantial increase in copper-induced enzyme activation. L-ascorbate by itself showed no direct stimulating effect in deficient chicks. When the L-ascorbate was given to chicks that had received adequate dietary copper, there was a strong rise in ceruloplasmin and a slight, but significant increase in lysyl oxidase. An increase in ceruloplasmin in response to copper was also seen in deficient chicks and L-ascorbate also augmented that increase. Substituting D-isoascorbic acid for antagonistic properties of L-ascorbic acid on copper metabolism, but they also reveal possible sterospecific postabsorption roles for L-ascorbate in the metabolism of copper.
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PMID:A postabsorption effect of L-ascorbic acid on copper metabolism in chicks. 611 9

Because high levels of dietary zinc are known to reduce copper body stores, the objective was to determine if a high zinc maternal diet could induce a copper deficiency in the newborn pig fed a dried skim milk--glucose--starch diet unsupplemented with copper. The offspring of gilts, which were fed 5000 ppm of zinc, were allowed to nurse until 3 to 5 days of age when they were weaned and placed in individual stainless-steel pens. The dietary treatments were 0, 5 and 10 ppm added copper from copper sulfate. After 14 days, pigs receiving the 0-ppm copper diet weighed significantly less (P less than 0.05) and had reduced hemoglobin, hematocrit and serum copper concentrations and no detectable ceruloplasmin activity. After 5 weeks, the pigs were killed, and tissues were collected. The unsupplemented group had 16.4% of the aortic lysyl oxidase activity of the 5-ppm group. Cytochrome c oxidase activity in the heart and liver, and copper stores in the heart, liver, pancreas and kidney were depressed (P less than 0.05) in unsupplemented pigs compared to those receiving 5 ppm copper. These data demonstrate that it is possible to produce quickly a markedly copper-deficient pig, by using the offspring of sows fed 5000 ppm zinc, and support previous conclusions that the dietary copper requirement of the baby pig is about 5 ppm.
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PMID:A copper deficiency in neonatal pigs induced by a high zinc maternal diet. 613 53

Of 8 Thoroughbred foals in which osteochondrosis developed before weaning, 7 had serum copper and ceruloplasmin concentrations below normal. Three foals on one farm had serum zinc content high enough to suggest zinc toxicosis, and the liver of each foal contained abnormally high content of zinc. Four foals from the second farm had extremely low serum copper content, but normal serum zinc content. Evidence of environmental exposure to excess zinc was not found on either farm. The lesions in the zones of endochondral ossification of the afflicted foals were similar in many respects to those found in other species of animals with molybdenum-induced copper deficiency and with inhibition of the function of copper-dependent lysyl oxidase by beta-aminopropionitrile, a toxic component of Lathyrus odoratus known to cause osteolathyrism.
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PMID:Considerations of copper metabolism in osteochondrosis of suckling foals. 674 86

Assays of serum benzylamine oxidase (BzAO) have led some workers to postulate a relationship between elevated BzAO activity and diseases characterized by proliferating connective tissue. The present study was designed to determine whether BzAO activity of a cellular tissue is also affected. BzAO was assayed in homogenates of normal and atherosclerotic human aortae. Characterization done in normal aortae showed that BzAO is not a classical monoamine, diamine, polyamine, or lysyl oxidase, nor is it a ceruloplasmin. The enzyme is heat stable at 60 degrees C and is associated primarily with the microsomal fraction on density centrifugation. Compared with phenylethylamines and indoleamines, benzylamine is the best substrate. BzAO is sensitive to inhibition by hydrazines and chymotrypsin but not trypsin, and is insensitive to Triton X-100 and sulfhydryl-group blockade. BzAO activity of atherosclerotic plaque (expressed per gram wet weight or per milligram protein) was decreased markedly compared to that in adjacent, nonplaque regions and in normal aortae. However, on a per milligram DNA basis, the BzAO activity of plaque did not differ from that of nonplaque tissue. We conclude that there is a decreased cell population density in plaque, a contention supported by kinetic analysis. Plaque BzAO showed a decreased Vmax with no change in the Km of benzylamine compared with nonplaque tissue. Thus, if a relationship exists between BzAO activity and proliferating connective tissue, it is not apparent at the level of the cellular enzyme in atherosclerotic aortae of man.
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PMID:Benzylamine oxidase in normal and atherosclerotic human aortae. 683 47

Copper serves as the cofactor for a number of important enzymes in cartilage, as well as in other tissues, including lysyl oxidase, superoxide dismutase, and cytochrome oxidase. Ceruloplasmin is responsible for the transport of approx. 95% of the copper in serum, but the mechanisms for intracellular copper transport are unknown. We have demonstrated recently that a high-molecular-weight cartilage glycoprotein, referred to as CMGP, has regions of sequence homology with ceruloplasmin. CMGP also binds copper and has at least some oxidase activity similar to that of ceruloplasmin. Other tissues synthesize intracellular ceruloplasmin-like proteins. The present report represents part of an effort to examine the hypothesis that CMGP is a copper transport protein in chondrocytes and to characterize the enzymatic activities of CMGP. These studies demonstrate that CMGP is the principal chondrocyte protein labeled by 67Cu in vitro and that the label is localized to the mitochondria, cytosol, and membrane fractions of sucrose gradients, suggesting copper transport through the cell. In parallel experiments, [3H]leucine was incorporated into proteins corresponding to the subunits and fragments of CMGP, as described previously, and in a similar distribution among the subcellular fractions as labeled copper. Additionally, CMGP has oxidase and ferroxidase activities similar to those of ceruloplasmin.
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PMID:Studies of copper transport in cultured bovine chondrocytes. 791 77

Occipital horn syndrome (OHS, Ehlers-Danlos syndrome type IX) belongs to the category of the copper metabolism disorders and is at present being investigated biochemically as is Menkes' disease. Unlike Menkes' disease, most patients with OHS have mild submentality. We report a case of OHS with severe central nervous system involvement and muscular atrophy in a 34-year-old male. He had psychomotor retardation and seizures since early childhood and now presented severe mental retardation and generalized muscular atrophy in addition to characteristic facial appearance, hyperelasticity of the skin and joint subluxation. Laboratory investigations revealed a low serum copper and ceruloplasmin level as well as intestinal non-absorption of copper. Radiographic imaging showed occipital exostoses, bladder diverticula, tortuosity of the peripheral vein and osteoporosis of the skeletal bones. The activity of lysyl oxidase, a copper-enzyme involved in cross-link formation in collagen, was found to be decreased in a skin-biopsy specimen. Electron-microscopic investigation of a muscle biopsy showed irregularity of the myofibrillar network and accumulation of concentric laminated bodies in the subsarcolemmal regions.
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PMID:Central nervous system involvement and generalized muscular atrophy in occipital horn syndrome: Ehlers-Danlos type IX. A first Japanese case. 809 5


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