Effects of thymol on atheroma plaque, concentration of blood lipids and atherogenic indices serum in male NMRI mice fed with a high-cholesterol diet

Atherosclerosis is characterized by the accumulation of fat and inflammatory response in the artery intima and can cause narrowing or complete blockage of the artery. Thymol is a phenolic monoterpene with antioxidant and anti-inflammatory properties. The aim of this study was to evaluate the effects of thymol on blood lipids, atherogenic indices and atheroma plaque of NMRI mice fed a high-cholesterol diet (HCD). 45 NMRI male mice were divided into 5 groups (n=9): Animals of the control group received a normal diet. Whiles in the HCD group received a diet containing 2% cholesterol for 18 weeks. Animals of the sham group received HCD for 12 weeks and then normal diet for 6 weeks with a thymol solvent (oil). The experimental groups 1 and 2 received HCD for 12 weeks and then received a normal diet with thymol at doses of 12 mg/kg and 24 mg/kg for 6 weeks, respectively. At the end of study, concentration of serum lipids and atherogenic indices were measured. Also aorta was measured microscopically. In the present study, consumption of HCD resulted in the formation of atheroma plaque, increased serum triglycerides, total cholesterol concentration, atherogenic indices and significantly decreased high density lipoprotein cholesterol (HDL-C). Treatment with both doses of thymol significantly reduced these changes and improves blood lipids, atherogenic indices was normal and atheroma plaques. The results of this study suggest that thymol can be used for treatment of increased total cholesterol and triglycerides and to improve the atheroma plaque.