Oxidative damage to nuclear DNA in hyperthyroid rat liver: Inability of vitamin C to prevent the damage


Andican G., Gelisgen R., Civelek S., Seven A. N., Seymen O., Altug T., ...Daha Fazla

JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH-PART A-CURRENT ISSUES, cilt.67, sa.5, ss.413-420, 2004 (SCI-Expanded) identifier identifier identifier

Özet

The effects of hyperthyroidism on oxidative DNA damage in liver tissue and modification by vitamin C supplementation were investigated in rats. Animals were rendered hyperthyroid by administration of L-thyroxine (0.4 mg/100g food) for 25 d. In the plasma samples, T-3, T-4, and thyroid-stimulating hormone (TSH) were measured by radioimmunoassay and ascorbate spectrophotometrically. Oxidative damage to hepatic nuclear DNA was determined by measuring deoxy-guanosine (dG) and 8-oxodG by high-performance liquid chromatography with diode array detector electrochemical detection (HPLC-DAD-ECD). In hyperthyroidism, 8-oxodG/(10(5) dG) levels were significantly higher and plasma vitamin C levels lower than in control rats. The results of this experimental study show that oxidative damage to hepatic nuclear DNA increases in the hyperthyroid state and that vitamin C was not effective in preventing this damage.