| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Atherosclerosis and Lipoproteins |
From the Université Pierre et Marie Curie-Paris 6 (A.K., J.A.d.S., S.C., M.J.C.), Paris; AP-HP, Groupe hospitalier Pitié-Salpétrière (A.K., J.A.d.S., S.C., M.J.C.), Paris; INSERM, Dyslipoproteinemia and Atherosclerosis Research Unit 551 (A.K., P.T., A.Z., M.C., A.N.-S., J.A.d.S., S.C., M.J.C.), Paris; Université Paris Descartes, Department of Biochemistry (P.T., A.Z., M.C.), EA 3617, Paris; and INSERM Unit 466 (A.N.-S.), CHU Rangueil, Toulouse, France.
Correspondence to Dr Anatol Kontush, INSERM Unité 551, Pavillon Benjamin Delessert, Hôpital de la Pitié, 83 boulevard de lHôpital, 75651 Paris Cedex 13, France. E-mail kontush{at}chups.jussieu.fr
Objective The purpose of this study was to define heterogeneity in the molecular profile of lipids, including sphingomyelin and sphingosine-1-phosphate, among physicochemically-defined HDL subpopulations and potential relevance to antiatherogenic biological activities of dense HDL3.
Methods and Results The molecular profile of lipids (cholesteryl esters, phospholipids, sphingomyelin, and sphingosine-1-phosphate) in physicochemically-defined normolipidemic HDL subpopulations was determined by high-performance liquid chromatography and gas chromatography. As HDL particle size and molecular weight decreased with increment in density, molar lipid content diminished concomitantly. On a % basis, sphingomyelin abundance diminished in parallel with progressive increase in HDL density from HDL2b (12.8%) to HDL3c (6.2%; P<0.001); in contrast, sphingosine-1-phosphate was preferentially enriched in small HDL3 (40 to 50 mmol/mol HDL) versus large HDL2 (15 to 20 mmol/mol HDL; P<0.01). Small HDL3c was equally enriched in LpA-I particles relative to LpA-I:A-II. The sphingosine-1-phosphate/sphingomyelin ratio correlated positively with the capacities of HDL subspecies to attenuate apoptosis in endothelial cells (r=0.73, P<0.001) and to retard LDL oxidation (r=0.58, P<0.01).
Conclusions An elevated sphingosine-1-phosphate/sphingomyelin ratio is an integral feature of small dense HDL3, reflecting enrichment in sphingosine-1-phosphate, a key antiapoptotic molecule, and depletion of sphingomyelin, a structural lipid with negative impact on surface fluidity and LCAT activity. These findings further distinguish the structure and antiatherogenic activities of small, dense HDL.
Preferential sphingosine-1-phosphate enrichment, but sphingomyelin depletion, distinguish normolipidemic small, dense HDL3 from large HDL2. Elevated sphingosine-1-phosphate/sphingomyelin ratio constitutes a hallmark of the lipid moiety of small dense HDL3 particles and is implicated in their antiatherogenic activity.
Key Words: sphingolipids phospholipid molecular species cholesteryl esters HDL particle remodeling
This article has been cited by other articles:
![]() |
R. Carnemolla, X. Ren, T. K. Biswas, S. C. Meredith, C. A. Reardon, J. Wang, and G. S. Getz The Specific Amino Acid Sequence between Helices 7 and 8 Influences the Binding Specificity of Human Apolipoprotein A-I for High Density Lipoprotein (HDL) Subclasses: A POTENTIAL FOR HDL PREFERENTIAL GENERATION J. Biol. Chem., June 6, 2008; 283(23): 15779 - 15788. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Mallat and A. Tedgui HDL, PTX3, and Vascular Protection Arterioscler. Thromb. Vasc. Biol., May 1, 2008; 28(5): 809 - 811. [Full Text] [PDF] |
||||
|
ATVB Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2007 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |