Increase of nitric oxide synthases and nitrotyrosine in inclusion-body myositis
Journal
NeuroReport
Journal Volume
8
Journal Issue
1
Start Page
153
End Page
158
ISSN
0959-4965
Date Issued
1997
Author(s)
Abstract
To investigate the possible role of nitric oxide (NO)-induced 'oxidative stress' in the pathogenesis of inclusion-body myositis (IBM), we immunostained muscle biopsies of 12 patients with IBM with isoform-specific antibodies against the neuronal and inducible forms of nitric oxide synthase and with antibodies against nitrotyrosine. Between 70 and 80% of IBM vacuolated muscle fibers contained inclusions strongly immunoreactive with all three antibodies, which by immuno-electronmicroscopy co-localized mainly to cytoplasmic paired-helical filaments, and also to amorphous structures and floccular material. Excess intracellular NO can combine with superoxide to produce highly reactive peroxynitrite which can nitrate tyrosines of proteins. The presence of nitrotyrosine is indicative of NO-induced "oxidative stress'. Our data suggest that this mechanism may play a pathogenic role in IBM.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Type
journal article