Agostach rugosa essential oils reduced plasma triglyceride and cholesterol levels in mice fed normal and high fat diet and suppressed 3‐hydroxy‐3‐methyl‐glutaryl‐Coenzyme a reductase expression in vitro and in vivo

Abstract

Agostach rugosa is a medicinal and ornamental plant in Korea and its essential oils have several bioactive compounds. The HepG2 cells were incubated with 0.1, 0.2, 0.4 and 1 mg/mL of Agostach rugosa essential oils (AREO) for 24 hrs. The mRNA and protein expressions were assessed by RT‐PCR and western blot analysis, respectively. At 1 mg/ml AREO treatment, the levels of the HMG‐CoA reductase mRNA and protein were significantly reduced, whereas the LDL receptor mRNA and protein levels were induced. Next, mice (C57BL/6CrSLC), either on chow or high fat diet, were orally administered with AREO for 6 weeks. In chow fed mice, plasma triglyceride and cholesterol levels were significantly decreased in AREO fed group. The plasma triglyceride levels were also significantly lowered in the AREO fed group compared with controls under high fat diet. The hepatic HMG‐CoA reductase mRNA and protein levels were significantly lowered in the AREO group after 6‐week feeding. These suggest that the AREO may be hypolipidemic by reducing the expression of HMG‐CoA reductase.