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)

Acid maltase deficiency is described in non-identical adult twins. The onset of the disease can be traced into late infancy; the clinical picture is one of severe muscular dystrophy; respiratory insuficiency was the cause of death in one case. The autopsy showed the central nervous system, heart and liver to be spared. Glycogen filled vacuoles are found in skin, mesenchymal cells, small nerves and skeletal muscles. The light microscopic study of 9 different muscles showed extremely variable involvement ranging from normal appearance to overt vacuolization. A 6--20% residual acid alpha-glucosidase activity was found in visceral organs, cultured fibroblasts and in some skeletal muscles. No satisfactory explanation can be given why this generalized acid alpha-glucosidase deficiency produces a selective involvement of skeletal muscles. If compared with infantile AMD (Pompe's disease) our cases have a much higher residual acid alpha-glucosidase activity and show the presence of an antigenically detectable protein. From our study and from a similar report in the literature (de Barsy et al., 1975), it appears that a combined approach of light microscopy, electron microscopy and biochemical analysis (determination of acid alpha-glucosidase) is necessary to make a diagnosis of AMD in adults.
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PMID:Acid maltase deficiency in non-identical adult twins. A morphological and biochemical study. 6 Apr 70

A 40-year-old man suffered for 5 years from a progressive proximal myopathy mimicking an atypical limb-girdle dystrophy. A "myopathic" pattern with myotonic and pseudomyotonic discharges was determined by electromyography. Enzyme histochemical and ultrastructural investigations of muscle and liver biopsies pointed to a glycogenosis. Biochemical investigations of muscle and liver samples confirmed this diagnosis, disclosing an acid maltase deficiency. Glycogen filled lysosomes were also revealed electron optically in skin fibroblasts but not in white blood cells. The literature concerning the late onset forms of acid maltase deficiency (type II glycogenosis) has been reviewed, and the clinical course has been compared with that of the infantile form (Pompe's disease). In early infancy the disease has a short and fatal course, with involvement of many organs. primarily skeletal muscules, liver and heart. In the late infantile and juvenile forms the course of the disease is slower, the organ involvement beeing not as severe; muscular symptoms begin to prevail. In adults, type II glycogenosis mimics muscular dystrophy with its prolonged course and the almost exclusive clinical involvement of proximal muscles. Biochemical and ultrastructural investigations have nevertheless demonstrated that other organs and tissues are also involved. The reasons for the variability of organ involvements in different ages are as yet unknown.
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PMID:[Pseudodystrophic muscle glycogenosis in adults. (Acid maltase deficiency syndrome) (author's transl)]. 6 Dec 60

Glycogen phosphorylase is a major sarcoplasmic protein and is one of the key regulatory enzymes in the control of glycogen utilisation. In C57BL/6J mice, the activity of the enzyme decreases under muscle-wasting conditions, including denervation-induced atrophy and muscular dystrophy. The cofactor of this enzyme, pyridoxal phosphate, has been employed as a specific label to permit measurement of the rate of degradation of the enzyme in vivo. In both of the muscle-wasting conditions, the decay of protein-bound label occurs at a higher rate than in normal animals, suggesting accelerated degradation of the enzyme. Additionally, we have used a monoclonal antibody, specific for pyridoxal phosphate, as a sensitive probe to search for degradation intermediates of this enzyme in vivo.
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PMID:Turnover of skeletal muscle glycogen phosphorylase. 357 81

Pompe disease is a severe form of muscular dystrophy due to glycogen accumulation in all tissues, especially striated muscle. Disease severity is directly related to the deficiency of acid alpha-glucosidase (GAA), which degrades glycogen in the lysosome. Respiratory dysfunction is a hallmark of the disease, muscle weakness has been viewed as the underlying cause, and the possibility of an associated neural contribution has not been evaluated previously. Therefore, we examined behavioral and neurophysiological aspects of breathing in 2 animal models of Pompe disease--the Gaa(-/-) mouse and a transgenic line (MTP) expressing GAA only in skeletal muscle, as well as a detailed analysis of the CNS in a Pompe disease patient. Glycogen content was elevated in the Gaa(-/-) mouse cervical spinal cord. Retrograde labeling of phrenic motoneurons showed significantly greater soma size in Gaa(-/-) mice vs. isogenic controls, and glycogen was observed in Gaa(-/-) phrenic motoneurons. Ventilation, assessed via plethysmography, was attenuated during quiet breathing and hypercapnic challenge in Gaa(-/-) mice (6 to >21 months of age) vs. controls. We confirmed that MTP mice had normal diaphragmatic contractile properties; however, MTP mice had ventilation similar to the Gaa(-/-) mice during quiet breathing. Neurophysiological recordings indicated that efferent phrenic nerve inspiratory burst amplitudes were substantially lower in Gaa(-/-) and MTP mice vs. controls. In human samples, we demonstrated similar pathology in the cervical spinal cord and greater accumulation of glycogen in spinal cord compared with brain. We conclude that neural output to the diaphragm is deficient in Gaa(-/-) mice, and therapies targeting muscle alone may be ineffective in Pompe disease.
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PMID:Neural deficits contribute to respiratory insufficiency in Pompe disease. 1947 95