This study was aimed at investigating lycopene activity on cyclooxygenase and lipid peroxidation in dexamethasone treated Wistar rats. Twenty (20) male Wistar rats weighing between 150g-250g were randomly selected into four groups containing five rats each. Control rats received standard feed and water. Group two received 3mg/kg body weight of dexamethasone intraperitoneally every two days for 9 days. Group 3 received 3mg/kg body weight of dexamethasone intraperitoneally every two days for 9 days plus daily oral administration of 1mg/kg of lycopene for 28 days. Results showed that there was no significant difference in activity of dexamethasone and lycopene on COX and THX-A2 in all the groups. Dexamethasone increased AST ALT and ALT level. Treatment with Lycopene significantly (p<0.01) decreased AST, ALT and ALP in all the groups. Lactate dehydrogenase activity was significantly (p<0.01) decreased in the dexamethasone and further lowered upon treatment with lycopene when compared to the DEX group. Malondealdehyde (MDA) concentration in Dex was increased (p<0.01), Catalase activity was reduced while SOD concentration was not altered. Treatment with lycopene Significantly (p<0.01) decreased serum MDA and increased catalase concentration. Triglyceride and LDL components of the lipid were elevated in Dex with a decreased HDL but without alteration in total cholesterol level. Lycopene decreased the TC, LDL and TG and significantly (p<0.01) increased HDL. It is concluded that dexamethasone suppresses cyclooxygenase expression but potentiates lipid peroxidation and increases liver enzymes. Lycopene inhibits Cox activity, protect against lipid peroxidation and is hypolipidemic and hepatoprotective.
