Abstract: Objective To study the effect of erythropoietin (EPO) on the activities of antioxidant enzymes, namely catalase (CAT)
and glutathione peroxidase (GSH-Px) in the brain tissues of aged rats. Methods Thirty SD rats were randomly divided into
normal control, aging model, and recombinant human erthropoietin (rhEPO) treatment groups (n=10). Morris water maze was
used to compare the behavioral indexes. The rats were then sacrificed to observe Nissl bodies in the hippocampal neurons
with Nissl staining and test the activities of CAT and GSH-Px in the brain tissues. Results Compared with the control group,
the aging rats showed significantly deteriorated learning and memory abilities (P<0.05), which were improved obviously by
rhEPO treatment (P<0.05). The number of Nissl bodies in the neurons was reduced in the aging rats compared with that in the
control group, and rhEPO treatment increased the number of Nissle bodies but failed to restore the control level. The aging
rats also showed significantly lowered activities of CAT and GSH-Px in the brain tissue (P<0.05), which were increased
significantly after rhEPO treatment (P<0.05). Conclusion EPO can enhance the activities of the antioxidant enzymes in the
brain tissues of aged rats to increase the antioxidant capacity and produces an anti-aging effect.