Targeting Lysophosphatidic Acid Ameliorates Dyslipidemia in Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is a lipoprotein disorder characterized by elevated plasma levels of low-density lipoprotein cholesterol (LDL-C) and an increased risk of premature atherosclerotic cardiovascular disease. Recent evidences have shown that several glycerophospholipid species were markedly altered in experimental FH animals and exhibited diverse bioactivities. Nevertheless, the glycerophospholipid profiles and their associated biological implications in human FH remain largely unknown. In this study, we sought to comprehensively delineate the glycerophospholipid phenotypes in human FH and to investigate the functional roles of key FH-altered glycerophospholipid molecules on cholesterol metabolism. Targeted analysis of 328 glycerophospholipid metabolites was used to profile the differentiated alterations in patients with homozygous FH (HoFH; n = 181), heterozygous FH (HeFH; n = 452), and non-FH hypercholesterolemia (n = 382). Our findings revealed that the glycerophospholipid phenotypes of FH and non-FH hypercholesterolemia were dominated by a spectrum of metabolites involved in the lysophosphatidic acid (LPA) metabolism. Among the LPA features, palmitoyl-LPA (16:0) showed significant association with the clinical levels of LDL-C and total cholesterol in HoFH and HeFH populations. Using functional metabolomic strategy and murine FH model, we demonstrated that supplementation with LPA 16:0 elevated the plasma levels of LDL and free/esterified cholesterol and exacerbated the atherosclerotic lesions. Conversely, inhibition of autotaxin-mediated LPA 16:0 production significantly ameliorated dyslipidemia. Mechanistically, we uncovered that LPA 16:0 could disrupt hepatic cholesterol homeostasis by impairing cholesterol excretion and inhibiting primary bile acid synthesis. In summary, our study offers novel insights into lipid metabolism in human FH and posits that targeting LPA metabolism may represent a promising therapeutic strategy for reducing cholesterol levels in the FH population.