Screening of Phenolic Compounds with Inhibitory Activities against HMG-CoA Reductase

페놀 화합물로부터 HMG-CoA reductase 저해 활성 물질 탐색

High level of plasma cholesterol is strongly associated with the development of atherosclerosis and coronary heart disease. Clinical trials designed to reduce plasma cholesterol level by diet or pharmacological intervention have resulted in marked reduction of disease incidence. The enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase which reduces cholesterol biosynthesis in the liver is the key enzyme of the mevalonate pathway that produces cholesterol. In this study, 71 naturally occurring phenolic compounds were tested for inhibitory activities against HMG-CoA reductase. Eleven compounds out of 71 showed inhibitory activities: three hydrolyzable tannin (geraniin, acetonyl geraniin and pentagalloyl ${\beta}-D-glucose$), four benzoic acid derivatives (benzoic acid, trans-cinnamic acid, 2,4-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid), and four naphthoquinone derivatives (1,2-naphthoquinone, 1,4-naphthoquinone, plumbagin and shikonin). At the concentration of $10{\mu}g/ml$, 1,4-naphthoquinone inhibited HMG-CoA reductase by 99.4%, and then plumbagin 91.4%, pentagalloyl ${\beta}-D-glucose$ 46.6%, 2,4-dihydroxybenzoic acid 40.9%, shikonin 37.7%, 1,2-naphthoquinone 36.6%, trans-cinnamic acid 32.0%, acetonyl geraniin 30.2%, benzoic acid 28.5%, geraniin 28.3% and 2,5-dihydroxybenzoic acid 22.3%, respectively. $IC_{50}$ values of 1,4-naphthoquinone and plumbagin was $2.1{\mu}g/ml$ and $5.8{\mu}g/ml$, respectively.

심혈관계 질환은 질환별 사망률 순위에 있어서 세계에서는 1위이며, 우리나라에서는 2위인 질병이다. 심혈관계 질환 발생의 주 위험 요인인 콜레스테롤은 HMG-CoA reductase에 의해 간에서 신생합성이 조절된다. 현재 고콜레스테롤혈증 치료에 statin이 널리 사용되고 있지만 광범위한 부작용이 보고되고 있어서 이를 대체하거나 보조할 수 있는 천연물 유래의 기능성 물질 개발이 필요한 실정이다. 따라서 본 연구에서는 혈장 콜레스테롤 감소 활성을 가지는 물질을 발굴하고자 71종의 페놀 및 그와 관련된 화합물들을 대상으로 10ug/ml 농도에서 HMG-CoA reductase 저해 활성을 탐색하였다. 그 결과, 1,4-naphthoquinone의 HMG-CoA reductase 저해율이 99.4%로 가장 높았고, 다음으로 plumbagin 91.4%, pentagalloyl ${\beta}-D-glucose$ 46.6%, 2,4-dihydroxybenzoic acid 40.9%, shikonin 37.7%, 1,2-naphthoquinone 36.6%, trans-cinnamic acid 32.0%, acetonylgeraniin 30.2%, benzoic acid 28.5%, geraniin 28.3%, gentisic acid 22.3%의 순이었다. $IC_{50}$값을 계산한 결과, 1,4-naphthoquinone가 $2.1{\mu}g/ml$로 가장 낮았으며, plumbagin과 pentagalloyl ${\beta}-D-glucose$은 각각 $5.8{\mu}g/ml$과 $13.1{\mu}g/ml$으로 나타났다. 1,4-naphthoquinone과 plumbagin의 경우, $5{\mu}g/ml$에서도 각각 90.3%와 43.3%의 저해율을 나타내었다.