Thymus atlanticus polyphenol-rich extract regulates cholesterol metabolism by inhibiting its biosynthesis without affecting its excretion in hamsters fed a high-fat diet

Context: Thymus atlanticus has been reported to have significant hypolipidaemic effect in animal models. However, the mechanism of this hypolipidaemic action still unknown. Objective: To determinate the possible mechanism(s) of hypolipidaemic action of a Thymus atlanticus polyphenol-rich extract (PRE). Materials and methods: Plasma, faecal, and liver cholesterol, bile acid content in the faeces, and gene expression level of HMG-CoA reductase, CYP7A1, ABCG5 and ABCG8 were analysed after 9 weeks in hamsters feeding normal diet, high-fat diet (HFD) or HFD supplemented with 400 mg/kg body weight/day of PRE. Results: PRE significantly decreased total cholesterol content (p <.05) and HMG-CoA reductase expression (p <.05), but did not affect the faecal cholesterol, bile acid contents and CYP7A1 and ABCG5/G8 expression (p >.05). Conclusion: We can conclude that the T. atlanticus extract is efficient in the alleviation of chronic hyperlipidaemia by acting as cholesterol biosynthesis inhibitor.