Sterol-O-Acyltransferase

Sterol O-acyltransferase (also: acyl-CoA: cholesterol acyltransferase ), an enzyme in the endoplasmic reticulum of animals, which catalyzes the esterification of cholesterol and cholesterol esters to fatty acids. From acyl -CoA and cholesterol CoA and cholesterol ester is doing. This reaction is important in order to convert an excess of cholesterol floating in the cytosol in an insoluble form of storage, thus avoiding undesired effects of free cholesterol. In humans, there are two isoforms, which are abbreviated as ACAT -1 and ACAT -2. Most frequently found in macrophages and ACAT -2 in the brush border ACAT -1.

Cholesterol reached among others by LDL particles into the cell or there is synthesized independently. LDL is hydrolyzed in lysosomes, and cholesterol, fatty acids and amino acids are released. Cholesterol is incorporated in the cell membrane, processed to hormones or bile acids or converted by ACAT again cholesterol esters, and so stored in a storage form. Accumulation of cholesterol esters in macrophages and smooth muscle are the first signs of atherosclerosis.

Can be inhibited the enzyme including through Lecimibid.