title: Advanced oxidation protein products in serum of patients with myotonic disease type I: association with serum gamma-glutamyltransferase and disease severity.
abstract: Steinert's disease (myotonic dystrophy type 1; MD) is caused by a CTG trinucleotide expansion on 19q13.3. Although the pathogenic mechanism underlying multisystem involvement in MD is still unclear, a role of oxidative stress in this disease has been suggested. We investigated 39 MD patients to assess the plasma concentration of advanced oxidation protein products (AOPPs) and gamma-glutamyltransferase (GGT) and related them to clinical severity scores. Plasma AOPP levels (p=0.021), total serum GGT activity (p=0.0005) and GGT activity associated with low-density lipoprotein (p=0.0021) were significantly higher in patients than in controls. There was significant correlation between serum GGT levels and AOPPs (r=0.5831; p=0.0022). A statistically significant increase in serum GGT with age was found in MD patients (p=0.0193). Receiver operating characteristic curve analysis showed that higher AOPP levels were significantly associated with extra-muscular signs of the disease, i.e., cataracts and heart involvement (area under the curve+/-SE=0.908+/-0.083), but not with muscular involvement. The concomitant increment in GGT and AOPPs indicates a possible role of oxidative stress in the pathogenesis of MD type 1, while the association of increased AOPP levels with extra-muscular signs of the disease suggests that individual susceptibility to oxidative stress can modulate the extra-muscular phenotype of the disease.
authors.affiliation: Department of Neuroscience, University of Pisa, Pisa, Italy. gsicilia@med.unipi.it
authors.forename: Gabriele
authors.initials: G
authors.lastname: Siciliano
authors.forename: Livia
authors.initials: L
authors.lastname: Pasquali
authors.forename: Anna
authors.initials: A
authors.lastname: Rocchi
authors.forename: Michela
authors.initials: M
authors.lastname: Falorni
authors.forename: Fabio
authors.initials: F
authors.lastname: Galluzzi
authors.forename: Angela
authors.initials: A
authors.lastname: Rocco
authors.forename: Gino
authors.initials: G
authors.lastname: Malvaldi
authors.forename: Alfonso
authors.initials: A
authors.lastname: Pompella
authors.forename: Aldo
authors.initials: A
authors.lastname: Paolicchi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001798:Blood Proteins / Q000737:chemistry / Q000378:metabolism*; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009223:Myotonic Dystrophy / Q000097:blood* / Q000145:classification / Q000201:enzymology*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D015415:Biomarkers; D001798:Blood Proteins; D005723:gamma-Glutamyltransferase