This study was undertaken to elucidate the possible effect of aging which is an extremely complex multifactorial process with various alterations in cellular components on some antioxidant defense enzymes system in liver, heart and brain of camels for this aim 30- male one-humped camels with age ranged between 1– 40 years and weighed 450-650 Kg. divided according to their ages into 3 groups each of 10- animals, Group (1) below 5 years old representing Young camels - control. Group (11) from 5 – 15 years – Adult , Group (111) over 15 years old - Aged camels .The obtained data showed a high significant increase in liver Superoxide dismutase (SOD),Glutathione peroxidase (GPX) activity of adult, this increase became highly significant in old, a significant increase in liver Catalase (CAT) activity of adult .Moreover a high significant decrease in old . A significant decrease in liver L-Malondialdehyde (MDA) content of adult, whereas a very high significant increase in old .A significant increase of heart SOD and CAT activities of adult, while a very high significant decrease of the heart SOD activity and a high significant decrease of the heart CAT activity in old .Whereas a significant decrease of heart MDA in adult and a significant increase of it in old .A non significant increase in CAT activity in brain of adult. While a significant decrease CAT in old. A significant increase in GPX and MDA in brain of adult, this increase became high significant at old. A high significant increase in brain Monoamine oxidase (MAO) activity in the adult, this increase became very high significant in the old. A high significant decrease in brain Acetyl cholinesterase (AchE) activity in adult, this decrease became a very high significant decrease in brain of old camels. It could be concluded that the antioxidant enzymes had vital role in protecting tissues from oxidative damages during aging an as them depletion increases the vulnerability of cellular components to reactive oxygen species.
Key Words: Antioxidant enzymes, liver, heart, brain and Camel.