Abstract

Apart from statins, fibrates and PCSK9 inhibitors there are the so called second line treatments in hyperlipidemia. Starting with the ones acting in cholesterol absorption, there are as well ezetimibe, nicotinic acid and in familial hypercholesterolemia the possible choice of LDL apheresis. Cholestyramineresin sequestering bile acids are effective drugs for LDL-C reduction, useful in patients who are contraindication to the use of vastatins, in the treatment of family hypercholesterolemia in children and as an association with other lipid-lowering agents. Unlike resins, ezetimibe is a selective inhibitor of intestinal cholesterol absorption. Ezetimibe inhibits intestinal absorption of cholesterol by inhibiting the Niemann Pick C1 Like1 protein on the surface of the enterocyte. This protein is responsible for the absorption of cholesterol, but not of other fats in the intestine. Its greatest advantage, however, is in the association with a vastatin, in a treatment strategy called double inhibition (inhibition of cholesterol synthesis by vastatin and its intestinal absorption by ezetimibe). Phytosterols compete in intestinal absorption of cholesterol, leading to a slight decrease in LDL-C. To act efficiently, they must be ingested before three meals. Nicotinic acid, which has been used as a lipid-lowering agent since 1955, is suitable for the treatment of all types of dyslipidemia except familial sistosterolemia. It can be used alone or associated with any lipid-lowering agent. The main mechanism of action of nicotinic acid is by inhibiting peripheral lipolysis, inhibiting the mobilization of fatty acids to the liver. Omega 3 fatty acids, eicosapentanoic and docosaexanoic acids have been used to treat severe hypertriglyceridemia at doses of 3 to 10g/day. The LDL-C apheresis method can be considered a type of selective hemodialysis, in which only LDL particles are removed from plasma.

Keywords: Phytosterol; Ezetimibe; Nicotinic acid; Omega 3; LDL apheresis; Cholestyramine

Abbreviations: ALT: Alanine Aminotransferase, Aminopeptidase N: CD 13, Apo A-1: Apoprotein A-1, AST: Aminotransferase, CK: Creatinoquinase, CYP3A4: Cytochrome P450 3A4 protein, HDL-C: High Density Lipoprotein Cholesterol, HMG-CoA Reductase: 3-Hidroxi-3-Methyl-Glutaril-CoA Reductase, LDL-C: Low Density Lipoprotein Cholesterol, VLDL: Very Low-Density Lipoprotein