Anti-inflammatory effects of cyclooxygenase-2 inhibitors in rabbits

Hypercholesterolemia is a major risk factor for atherosclerosis while homocysteine and c reactive protein are systemic inflammatory markers elevated in hypercholesterolemia and are by themselves,strong and independent risk factors for developing atherosclerosis. the main objective of this investigation was to determine the effects of cyclooxygenase-2 inhibitors,nimesulide and celecoxib on homocysteine and c reactive protein during experimentally induced hypercholesterolemia in rabbits. rabbits were divided into four groups; group 1 served as control and consist of normal rabbits that received saline,group 2 consisted of rabbits that were fed high cholesterol diet and received saline,group 3 consisted of rabbits fed with high cholesterol diet that received nimesulide (25 mg/kg) while group 4 consisted of rabbits fed with high cholesterol diet and received celecoxib (25 mg/kg). rabbits were fed with high cholesterol diet for twenty (20) weeks while their blood was withdrawn every two week for measuring lipid profile and inflammatory biomarkers. our study indicates that hypercholesterolemia results in elevation of homocysteine and c reactive protein while pretreatment with nimesulide was more effective than celecoxib in bringing down their concentrations to the baseline. further investigation shows that these effects of cyclooxygenase 2 inhibitors may be mediated through changes in the activity of paraoxonase 1 and concentration of high density lipoprotein. we conclude that use of cyclooxygenase 2 inhibitors,nimesulide and celecoxib can lower c reactive protein and homocysteine levels in diet-induced hypercholesterolemia in rabbits. copyright © 2015 zoological society of pakistan.