Gender-dependent variations in systemic biomarkers of oxidative protein, DNA, and lipid damage in aged rats.
BACKGROUND
The effect of aging on plasma-protein, lipid and DNA oxidation is well documented. However, none of the studies specify the effect of gender. The purpose of this study is to clarify the ambiguity raised in preliminary reports as to gender dependency of oxidative damage in plasma.


METHODS
In the current study, we investigated the relation between 8-hydroxy-2'-deoxyguanosine levels (8-OHdG), which is a measure of DNA oxidation and protein oxidation parameters such as protein carbonyl (PCO), total thiol (T-SH), and advanced oxidation protein products (AOPP). Our study also covered other oxidative stress parameters, such as lipid hydroperoxides (LHP), malondialdehyde (MDA), erythrocyte glutathione (GSH), superoxide dismutase (Cu-Zn SOD) and the catalase (CAT) activity in plasma of the male and female aged rats.


RESULTS
8-OHdG and MDA levels in male rats were significantly higher than those in the female group (p < 0.01 for both parameters). T-SH levels were found to be higher in female rats than in the male (p < 0.05). Plasma Cu-Zn SOD activities of male rats were significantly higher compared with those of the female rats (p < 0.05). On the other hand, PCO, AOPP, LHP, GSH levels, and CAT activity were not found to be different between genders.


CONCLUSIONS
We suggest that increased T-SH levels found in female rats may point to an adaptive reaction to oxidative damage, reflecting 8-OHdG and MDA overproduction. We are of the conviction that the increased 8-OHdG and MDA that we have determined in aged male rats may be a risk factor in the extent of oxidation in plasma.
Cakatay
Ufuk
U
Istanbul Faculty of Medicine, Central Laboratory of Clinical Biochemistry, Istanbul University, Istanbul, Turkey. cakatay@yahoo.com
Aydin
Seval
S
Yanar
Karolin
K
Uzun
Hafize
H
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D002374:Catalase / Q000097:blood; D004249:DNA Damage / Q000502:physiology*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000097:blood; D005260:Female; D005978:Glutathione / Q000378:metabolism; D008054:Lipid Peroxides / Q000097:blood*; D008136:Longevity; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D018384:Oxidative Stress / Q000502:physiology*; D050050:Protein Carbonylation; D051381:Rats; D017208:Rats, Wistar; D012737:Sex Factors; D013438:Sulfhydryl Compounds / Q000097:blood; D013482:Superoxide Dismutase / Q000097:blood
D008054:Lipid Peroxides; D013438:Sulfhydryl Compounds; D008315:Malondialdehyde; D000080242:8-Hydroxy-2'-Deoxyguanosine; D002374:Catalase; D013482:Superoxide Dismutase; D003849:Deoxyguanosine; D005978:Glutathione