title: Oxidative stress markers during a course of hyperthyroidism.
abstract: BACKGROUND
  Previous studies have shown the presence of oxidative stress in hyperthyroid patients. The aim of this study was to evaluate the influence of hyperthyroidism on lipid peroxidation, plasma lipoprotein oxidation and antioxidant status. We have estimated the clinical utility of the biochemical parameters analysed as markers of oxidative stress in hyperthyroidism.
  
  
  METHODS
  Twenty five patients with overt hyperthyroidism because of Graves' disease or toxic multinodular goitre and 20 healthy subjects were included in the study. Lipid peroxidation was evaluated by measurement of peroxides and malondialdehyde with 4-hydroxynonenal (MDA + 4-HNE) concentrations. Autoantibodies against oxidised LDL (anti-oxLDL) were assayed as a marker of lipoprotein oxidation. Changes in the antioxidant defence system were estimated by measurement of total antioxidant status in serum (TAS) and erythrocyte superoxide dismutase activity (SOD).
  
  
  RESULTS
  A significant increase in serum concentration of peroxides and MDA + 4-HNE was observed in patients with hyperthyroidism. However, no difference was found in anti-oxLDL concentration and antioxidant status parameters (TAS, SOD) between the control group and the patient group.
  
  
  CONCLUSIONS
  Our results indicate an intensification of the oxidative processes caused by an excess of thyroid hormones, which is not accompanied by a response from the antioxidant system. Elevated concentrations of lipid peroxidation products in serum, both peroxides and malondialdehyde with 4-hydroxynonenal, may be useful as markers of oxidative stress during the course of hyperthyroidism.
authors.affiliation: Department of Pathobiochemistry and Clinical Chemistry The Ludwik Rydygier Collegium Medicum, Bydgoszcz, Nicolaus Copernicus University, Toruń. lampka@cm.umk.pl
authors.forename: Magdalena
authors.initials: M
authors.lastname: Lampka
authors.forename: Roman
authors.initials: R
authors.lastname: Junik
authors.forename: Anna
authors.initials: A
authors.lastname: Nowicka
authors.forename: Ewa
authors.initials: E
authors.lastname: Kopczyńska
authors.forename: Tomasz
authors.initials: T
authors.lastname: Tyrakowski
authors.forename: Grazyna
authors.initials: G
authors.lastname: Odrowaz-Sypniewska
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000503:physiopathology*; D015227:Lipid Peroxidation; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008875:Middle Aged; D018384:Oxidative Stress; D012016:Reference Values
chemical_list: D015415:Biomarkers; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; D008315:Malondialdehyde