Potential oxyradical damage and energy status in individual muscle fibres from degenerating muscle diseases.
Inherited degenerating muscle diseases result in disintegration of muscle fibres, which is initiated by a lack of or alteration to a muscle protein. In Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) the protein is known to be dystrophin. The cellular function of dystrophin is not known in any detail but its absence appears to lead to a weakening of the sarcolemma. It has been proposed by Murphy and Kehrer that this leads ultimately to increased oxyradical production which may accelerate the degeneration. Studies have been carried out on individual muscle fibres derived from biopsy samples from patients with a number of degenerative muscle diseases. The glutathione cycling components, in particular glutathione and glutathione peroxidase, are significantly elevated in DMD, BMD and other diseases. Glutathione reductase is also elevated in some of these diseases. Energy producing systems are also affected particularly in intact fibres of muscle derived from muscle at an advanced stage of the disease. These results suggest that oxyradical damage may occur as a secondary consequence of muscle degenerating disease, leading to a breakdown in the glycogenolytic energy producing system.
Austin
L
L
Department of Biochemistry, Monash University, Victoria, Australia.
de Niese
M
M
McGregor
A
A
Arthur
H
H
Gurusinghe
A
A
Gould
M K
MK
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D004734:Energy Metabolism / Q000502:physiology*; D005609:Free Radicals; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D008297:Male; D009132:Muscles / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D009136:Muscular Dystrophies / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D010100:Oxygen / Q000633:toxicity*; D010725:Phosphocreatine / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
D005609:Free Radicals; D010725:Phosphocreatine; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione; D010100:Oxygen