Familial hypercholesterolemia and triglyceride metabolism

Familial hypercholesterolemia (FH) is a common autosomal disorder associated with hypercholesterolemia which usually results from a mutation in the coding region of the low density lipoprotein (LDL) receptor (R) activity. Only 20% of untreated heterozygote (h) FH men reach 70 years of age. Therefore, the diagnosis of hFH is a better predictor of coronary heart disease than risk-based algorithms. Fasting and postprandial hypertriglyceridemia are also considered as risk factors for atherosclerosis. The plasma triglycerides (TG)s are formed from two major sources; intestinally-derived chylomicrons and hepatically-derived very low density lipoproteins (VLDL). Potentially, atherogenic remnants of TG-rich lipoproteins accumulate in the postprandial state. In addition, TG-rich lipoproteins may promote the formation of atherogenic small dense LDL. In FH subjects, lipoprotein metabolism seems to be impaired and may contribute to premature atherosclerosis. This was documented in many studies in which mice lacking LDLR present hypercholesterolemia, increased plasma TG-rich lipoprotein remnants and develop premature spontaneous atherosclerosis. In this review, we focus on the current knowledge regarding TG metabolism on a selected clinically condition such as FH. Variation in clinical characteristics has been described between studies which may occur due to dissimilarity in the molecular defect of FH. Additionally, the relationship between TG levels in FH subjects and the development of atherosclerosis, as well as the appropriate treatment for these patients is analysed.