Background-Angiopoietin-like protein 3 (ANGPTL3) affects lipid metabolism by inhibiting the activity of lipoprotein and endothelial lipases. Angptl3 knockout mice have marked hypolipidemia, and heterozygous carriers of ANGPLT3, loss-of-function mutations were found among individuals in the lowest quartile of plasma triglycerides in population studies. Recently, 4 related individuals with primary hypolipidemia were found to be compound heterozygotes for ANGPTL3 loss-of-function mutations. Methods and Results-We resequenced ANGPTL3 in 4 members of 3 kindreds originally identified for very low levels of low-density lipoprotein cholesterol and high-density lipoprotein cholesterol (0.97=0.16 and 0.56=0.20 mmol/L, respectively) in whom no mutations of known candidate genes for monogenic hypobetalipoproteinemia and hypoalphalipoproteinemia had been detected. These subjects were found to be homozygous or compound heterozygous for ANGPTL3 loss-of-function mutations (p.G400VfsX5, p.I19LfsX22/p.N147X) associated with the absence of ANGPTL3 in plasma. They had reduced plasma levels of triglyceride-containing lipoproteins and of HDL particles that contained only apolipoprotein A-I and pre-β-high-density lipoprotein. In addition, their apolipoprotein B-depleted sera had a reduced capacity to promote cell cholesterol efflux through the various pathways (ABCA1-, SR-BI-, and ABCG1-mediated efflux); however, these subjects had no clinical evidence of accelerated atherosclerosis. Heterozygous carriers of the ANGPTL3 mutations had low plasma ANGPTL3 and moderately reduced low-density lipoprotein cholesterol (2.52=0.38 mmol/L) but normal plasma high-density lipoprotein cholesterol. Conclusions-Complete ANGPTL3 deficiency caused by loss-of-function mutations of ANGPTL3 is associated with a recessive hypolipidemia characterized by a reduction of apolipoprotein B and apolipoprotein A-I- containing lipoproteins, changes in subclasses of high-density lipoprotein, and reduced cholesterol efflux potential of serum. Partial ANGPTL3 deficiency is associated only with a moderate reduction of low-density lipoprotein.
|Titolo:||Characterization of Three Kindreds With Familial Combined Hypolipidemia Caused by Loss-of-Function Mutations of ANGPTL3|
|Settore Scientifico Disciplinare:||Settore BIO/14 - Farmacologia|
|Data di pubblicazione:||2012|
|Digital Object Identifier (DOI):||10.1161/CIRCGENETICS.111.960674|
|Appare nelle tipologie:||01 - Articolo su periodico|