Age-correlated changes of the erythrocyte catalase activity in the Spanish population.

Background: Oxygen free radical and reactive oxygen species are involved in many diseases and ageing. Scavening enzymes represent one of the several natural defence mechanisms against free radical induced damage. Catalase (CAT) is an enzyme that is involved in antioxidant defence.

Objective: In order to establish a comprehensive profile of the erythrocyte CAT activity during ageing, we investigated this activity in human erythrocytes from 2,827 apparently healthy Spanish subjects (1,388 males and 1,439 females).

Methods: We divided the subjects into twelve age groups (newborns and 1-3, 4-9, 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, 80-89, and >90 years of age) to evaluate ageing changes. The CAT activity was measured in haemolysates by the method of Aebi (see text).

Results: No significant variations with respect to sex were detected, except for the 70- to 93-year age groups. In these elderly subjects, the CAT activity in males remained constant with no significant variations between age groups, whereas the CAT activity showed a significant increase in females. This fact is considered to be one of the outcomes of the greater longevity in females. Significant age-related modifications in erythrocyte CAT activity appeared in the group of newborns (p < 0.001), in the group 1-3 years of age (p < 0.025), and in the elderly groups: 70-79 years (p < 0.025) and 80-89 years (p < 0.05) of age.

Conclusion: Our results confirm that the CAT activity in the Spanish population shows an interindividual variability and suggest that this variability may be due, at least in part, to the age of the individuals.