An Experimental Study Of 5α- Cholestane Intravenous Subnano-emulsion On Atherosclerosis In Rabbits

Objective: To observe the effects of 5α- cholestane intravenous subnano-emulsion regressing atherosclerosis in rabbits by hyperlidemic diet and explore the possible mechanismMethods:Twenty four New-Zealand rabbits were randomly divided into three experimental groups after being fed with normal diet for 1 weeks, Group Normal were fed with normal diet always,Group HCHL were fed with hypercholesterolemic diet,and Group HCHL+CHS were fed with hypercholesterolemic diet with i.v administration of 5α- cholestane intravenous subnano-emulsion. at a dose of 5 mg·kg-1·qod in the morning. Before and at the 0th, 5th ,9th-week after treatment,blood samples were collected from rabbits in all groups.Serumwas separated and used for assessment of serum total cholesterol(TC),triglyceride(TG),high density lipoprotein cholesterol(HDL-C),and low density lipoprotein cholesterol(LDL-C),as well as used for assessment of inflammation related factors including serum tumor necrosis factor-α(TNF-α),and interleukin -1β(IL-1β), Experimental animals were sacrificed at the 9th week, their aortas were taken out and stained with Sudan red IV.Image-Pro plus 6.0 was used to measure the percentage of atheromatous plaques in the area of tunica intima.Aortic arch HE stained sections observed under light microscope plaques and intima-media thickness;liver biopsy HE staining, light microscope observation change of liver structure.Results:1. After hypercholesterolemic diet, the levels of TC, TG, HDL-C, and LDL-C, were significantly higher in the two relevant groups than those before the administration of hypercholesterolemic diet (P<0.05). Encourageously the levels of TC, TG, HDL, and LDL were significantly lower in group HCHL+CHS than those in group HCHL with statistical difference (P<0.05). In group HCHL+CHS than those in group HCHL (P<0.05).2. The relative plaque area was significantly lower in group HCHL+CHS than those in group HCHL (P<0.01)3. Pathologicstaining: Pathologic staining demonstrated that the intima was thin and complete in group normal diet.A great quantity of widespread fatty plaques were observed in group HCHL, in which intima thickened and foam cell accumulated obviously.In contrast, in the HCHL+CHS group, plaque thickness diminished and both quantity and volume of foam cell were significantly decreased in the aorta of rabbits in the HCHL+CHS group.The intima and Tunica media vasorum thickness in group HCHL were significantly higher than the relevant values in in the HCHL+CHS prevention group.The I/M of artery in the group HCHL was higher than in the HCHL+CHS prevention group (P<0.01).4. The degree of liver fat accumulation, group HCHL+CHS was significantly less severe than group HCHL (P < 0.01).5. Detection of inflammatory factors: serum concentration of TNF-α, IL-1, There was no significant difference between Group HCHL + CHS and group HCHL.Conclusion: 5α-cholestane intravenous subnano-emulsion regressing the atheromatous plaque formation through decreasing serum lipid.