Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027121 (myositis)
 4,538 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxidative stress has been implicated in the pathogenesis of several muscle diseases. Semicarbazide-sensitive amine oxidase (SSAO) metabolizes oxidative deamination of primary aromatic and aliphatic amines. In the oxidative reactions, amine substrates are converted into the aldehyde, followed by the production of ammonia and H(2)O(2). Although normal levels in muscle are very low, SSAO is expressed in almost all mammalian tissues. In this study, we examined the possible implication of SSAO as an additional source of oxidative stress in the pathogenesis of muscle disorders. The expression of SSAO was examined immunohistochemically in muscle biopsy specimens from patients with inclusion-body myositis (IBM; n = 5), desmin-related myopathy (DRM; n = 3), dermatomyositis (n = 3), granulomatous (sarcoid) myopathy (n = 2), muscle denervation-reinnervation (n = 3), and rhabdomyolysis (n = 2), as well as from control subjects (n = 3). Strong SSAO immunoreactivity was present in vacuolated and nonvacuolated fibers in IBM, in abnormal fibers in DRM, and in degenerating and regenerating fibers in dermatomyositis and rhabdomyolysis. In addition, SSAO overexpression was observed in muscle fibers adjacent to granulomas in sarcoid myopathy. These results suggest that SSAO is a source of oxidative stress in diseased human skeletal muscle and that it contributes to oxidative stress-induced damage in various inflammatory and other myopathies. Alternatively, the expression of SSAO in muscle fibers may be a consequence of muscle fiber injury.
 ...
PMID:Overexpression of semicarbazide-sensitive amine oxidase in human myopathies. 1475 92

We describe the case of a 69-year-old man with a history of muscular symptoms dating back to his childhood; McArdle's disease (glycogen-storage disease V) was diagnosed following an episode of myositis in which a statin and physical exertion appear to have been precipitating factors. This case demonstrates that the ischaemic lactate-ammonia test still has a place in screening patients with symptoms suggestive of McArdle's disease and emphasizes the importance of carrying out glycogen phosphorylase histochemistry on the skeletal muscle biopsy to confirm the diagnosis. In patients who develop a raised plasma creatine kinase level or muscular symptoms during lipid-lowering therapy, the clinician should be alert to the possibility of an underlying myopathy.
 ...
PMID:McArdle's disease diagnosed following statin-induced myositis. 1529 48