Superoxide dismutase, catalase and glutathione peroxidase activities in human blood: influence of sex, age and cigarette smoking.
OBJECTIVE
To obtain reference ranges for each of the main antioxidant enzymes (AOE) and analyze the influence of sex, age, and cigarette smoking on AOE activity in human blood.


METHODS
We investigated superoxide dismutase (SOD), catalase (CAT), and seleno-dependent glutathione peroxidase (GSH-Px) activities in the whole blood from 103 healthy subjects, from 18-67 years old (51 males and 52 females).


RESULTS
We found a large and highly significant interindividual variability in the activity of all the AOE studied (p < 0.001). The interindividual coefficients of variation were 13.5% for SOD, 21.0% for CAT, and 36.2% for GSH-Px, indicating that GSH-Px exhibits the highest interindividual variability. Females showed higher SOD (p < 0.001) and CAT (p < 0.001) activities but lower GSH-Px (p < 0.05) activity than males. We found a significant effect of age on SOD activity (p < 0.001), showing that in human blood it decreases with age and that this decrease is not linear, beginning at 28 years of age. We also observed a linear effect of age on GSH-Px activity indicating that the activity of this enzyme increases with age (p < 0.01). No effect of age on CAT activity was observed (p > 0.05). AOE activity in smokers was found not to be significantly different from that observed in non-smokers (p > 0.05) except in the case of CAT activity in females, which was found to be lower in smokers than in non-smokers (p < 0.05). In addition, we determined reference ranges for the activity of each antioxidant enzyme studied.


CONCLUSIONS
Our results confirm that AOE activity in human blood exhibits a wide interindividual variability and suggest that this variability may be ascribed, at least in part, to the sex and age of the individuals. Moreover, our results suggest that cigarette smoking does not influence AOE activity in human blood. Accordingly, it is suggested that for clinical purposes it may be necessary to consider the sex and age of the subjects involved in the study.
Bolzán
A D
AD
Instituto Multidisciplinario de Biología Celular (IMBICE), La Plata, Argentina.
Bianchi
M S
MS
Bianchi
N O
NO
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002374:Catalase / Q000097:blood*; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012737:Sex Factors; D012907:Smoking; D013482:Superoxide Dismutase / Q000097:blood*
D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase