Effect of feeding Thymus daenensis Celak. essential oil on the serum lipid profiles, urea and liver enzymes in hypercholesterolemic male Wistar rats

Background and Objective: Hyperlipidemia and high level of serum total cholesterol are risk factors contributing to prevalence and severity of cardiovascular complications like coronary heart diseases. Lamiaceae plants have terpenoids and flavonoids can reduce triglyceride and cholesterol, therefore. This study was done to evaluate the effect of feeding with essential oil of Thymus deanensis Celak. on lipid profile, blood urea and liver enzymes in hyperchlostrolemic male Wistar rats. Methods: This experimental study was performed on 36 male Wistar rats. Animals were randomly divided into 6 groups (there were 6 rats in each groups). The groups including control, sham, two groups receiving 200 and 500 ppm Thymus deanensis essential oil and hyperchlostrolemia groups treated with doses of 200 and 500 ppm of Thymus deanensis essential oil. Hyperchlostrolemia was induced by giving high cholesterol (2%) and sweet almond oil (97.5%) diet. The animals were treated for 32 days with essential oil of the thyme. At the end of the 32-day trial, blood sampling was performed. Total cholesterol, triglyceride, urea and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) liver enzymes were measured. Results: The level of ALT and AST in hypercholesterolemia rats were significantly increased in comparison with the control group (P˂0.05). Thymus daenensis essential oil significantly reduced level of triglycerides and cholesterol (P˂0.05). The high dose of Thymus daenensis (500 ppm) essential oil more than a low dose (200 ppm) significantly reduced the level of cholesterol and triglyceride (P˂0.05). Blood urea nitrogen significantly increased in hypercholesterolemia group in compare to control group (P˂0.05). After the administration of essential oil with a minimum and maximum dose in hypercholesterolemia rats, the level of urea in the blood significantly decreased (P˂0.05). The level of ALT and AST in hypercholesterolemia rats significantly increased in comparison with the control group (P˂0.05). AST level significantly reduced in the groups of rats which received minimal and maximal doses compared to the group hypercholesterolemia (P˂0.05). Conclusion: By lowering blood lipids, urea and liver enzymes after the use of essential oils, it seems that the Thymus daenensis dose-dependent is effective in improving liver function, kidney and high level of  lipid.