Down-regulation of cholesterol biosynthesis in sitosterolemia: diminished activities of acetoacetyl-CoA thiolase, 3-hydroxy-3-methylglutaryl-CoA synthase, reductase, squalene synthase, and 7-dehydrocholesterol delta7-reductase in liver and mononuclear leukocytes.


Sitosterolemia is a recessively inherited disorder characterized by abnormally increased plasma and tissue plant sterol concentrations. Patients have markedly reduced whole body cholesterol biosynthesis associated with suppressed hepatic, ileal, and mononuclear leukocyte 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-controlling enzyme… (More)