Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To elucidate the metabolic abnormality of musclar dystrophy, 27 kinds of enzyme activity in various organs of control and dystrophic mice were examined. The organs examined included muscle, bone, heart, testis, uterus, spleen, thymus, submaxillary gland, stomach, pancreas, liver, kidney, brain, and lung. The activities of 14 different aminopeptidases, 5 endopeptidases, 4 glycosidases, phosphatase, esterase, and ribonuclease were measured. Most of the enzyme activities were significantly elevated in muscles and bones of dystrophic mice. These organs were similar in their patterns of enzyme abnormality. Among the 14 kinds of aminopeptidase activity studied, the degree of increased activity was greater for the aminopeptidases (AP):Ala-AP, Leu-AP, Met-AP, Phe-AP, Trp-AP, Gly-Pro-Leu-AP. In addition to aminopeptidases, there were significant increases in activities of chymotrypsinlike enzyme, cathepsin C, cathepsin D, several glycosidases and neutral ribonuclease in the muscles of dystrophic mice. Similarly increased enzyme activity was also observed in organs other than muscle and bone. Furthermore, protein content in most organs was higher in dystrophic mice than in those of control mice. These abnormalities were seen in both males and females. The present results suggest that there are extensive abnormalities in the protein metabolism in dystrophic mice. It seems therefore that the therapeutic approach to muscular dystrophy should be studies not only from the well-known abnormality of intramuscular endopeptidases, but from other aspects as well.
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PMID:Various enzyme activities in muscle and other organs of dystrophic mice. 625 14

The activities of four lysosomal and two nonlysosomal hydrolases were studied in skeletal muscle biopsy samples from patients with neuromuscular diseases and from controls. beta-Glucosaminidase activity was increased in polymyositis. beta-Glucuronidase and alkaline protease activities were elevated in muscular dystrophy in adults, whereas cathepsin D activity was increased in amyotrophic lateral sclerosis. There were significant correlations between the activities of lysosomal and nonlysosomal hydrolases. The activity of beta-glucuronidase, beta-glucosaminidase, alkaline protease, and dipeptidyl aminopeptidase IV showed a positive correlation with the severity of muscular atrophy. The activities of these hydrolases and the activity of dipeptidyl aminopeptidase I correlated positively with the activities of muscular galactosylhydroxylysyl glucosyltransferase and with the serum concentration of type III procollagen aminoterminal propeptide. The results suggest that in neuromuscular diseases the lysosomal and nonlysosomal pathways for muscle degradation are affected concomitantly with collagen biosynthesis.
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PMID:Lysosomal and nonlysosomal hydrolases of skeletal muscle in neuromuscular diseases. 635 16

Several lysosomal enzymes were assayed in cultured human skin fibroblasts from patients with Duchenne's muscular dystrophy (DMD) and age- and sex-matched control patients (N). The activity of four glycosidases, cathepsin B(1), and total autoproteolysis at pH 4.0 were unchanged between the groups, but dipeptidyl aminopeptidase I (DAP-I, or cathepsin C) in the DMD cells was found to be only 30% as active as in the control cells (P < 0.003). This difference is not the result of a redistribution or loss of enzyme during homogenization because the difference occurs in all homogenate fractions. DAP-I activity existing in N and DMD fibroblasts behaves identically with respect to activation by chloride ion, activation by the sulfhydryl reducing agent dithiothreitol, changes in hydrogen ion concentration (pH), changes in substrate concentration (i.e., apparent K(m) values), and changes in temperature (i.e., apparent activation energies). Mixtures of N and DMD cell sonicates display an additivity in DAP-I activity. These results support the conclusion that the catalytic function of the DAP-I molecule is equivalent between N and DMD fibroblasts, and that the decrease in tissue-specific DAP-I activity probably results from the fact that fewer enzyme molecules are present in the DMD cells. These results are also an indication that these nonmuscle cells are expressing some of the phenotypic aspects of the genetic defect in DMD. Cultured human skin fibroblasts may therefore be a useful cellular model in DMD research.
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PMID:Decreased lysosomal dipeptidyl aminopeptidase I activity in cultured human skin fibroblasts in Duchenne's muscular dystrophy. 677 86