Abstract

Regression and suppression of atherosclerotic lesion may be a realistic goal in some patients. Antioxidants and hypolipidemic agents suppress the development of hypercholesterolemic atherosclerosis and induce regression of atherosclerosis. The objectives of this study were to determine effects of Hypericum perforatum L. (HPL) on regression of atherosclerosis in hypercholesterolemic rabbits.  Rabbits were assigned to four groups: Group I control diet (75 days); Group II cholesterol diet (75 days); Group III cholesterol diet (45 days) followed by regular diet (30 days); Group IV cholesterol diet (45 days) followed by regular diet and HPL (30 days). Blood samples were collected from rabbits before and after 45 days and 75 days respective for measurement of biochemical factors. At the end, aorta was removed for assessment of atherosclerotic plaques. It increases in serum total cholesterol, triglycerides (TG), low density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), apolipoproteinB (apoB), AI, high-sensitive C-reactive protein (hs-CRP), Malondialdehyde (MDA), oxidized LDL (OX-LDL), apolipoproteinA (apoA), white blood cell (WBC), fibrinogen and platelet in Group II,III, ΙV on the 45^th days, comparing with Group Ι and the beginning of the study. At the end, biochemical factors serum decreased in Groups III and ΙV. There was more Biochemical factors serum and atherosclerotic lesions decreased in Groups IV compared to Group III in regression period. The reduction in atherosclerotic lesions was associated with a reduction in oxidative stress. These results suggest that regular diet following a high cholesterol diet accelerates atherosclerosis; HPL treatment prevents the progression of atherosclerosis on Group IV;  prevention of progression is associated with a reduction of inflammatory factors and antioxidant mechanism may  induces regression of atherosclerosis lesion.  

Key words: Atherosclerosis, regression, Hypericum perforatum, rabbits, oxidized low density lipoprotein (OX-LDL), C-reactive protein, white blood cell (WBC), fibrinogen, platelet.