0000000000186400
AUTHOR
Catherine Desrumaux
showing 9 related works from this author
Mass Concentration of Plasma Phospholipid Transfer Protein in Normolipidemic, Type IIa Hyperlipidemic, Type IIb Hyperlipidemic, and Non–Insulin-Depen…
1999
Abstract —Mean plasma phospholipid transfer protein (PLTP) concentrations were measured for the first time by using a competitive enzyme-linked immunosorbent assay. PLTP mass levels and phospholipid transfer activity values, which were significantly correlated among normolipidemic plasma samples ( r =0.787, P <0.0001), did not differ between normolipidemic subjects (3.95±1.04 mg/L and 575±81 nmol · mL −1 · h −1 , respectively; n=30), type IIa hyperlipidemic patients (4.06±0.84 mg/L and 571±43 nmol · mL −1 · h −1 , respectively; n=36), and type IIb hyperlipidemic patients (3.90±0.79 mg/L and 575±48 nmol · mL −1 · h −1 , respectively; n=33). No significant correlations with plasma lipid p…
α-Tocopherol Modulates Phosphatidylserine Externalization in Erythrocytes
2006
Objective— The aim of the present study was to assess the effect of α-tocopherol, the main vitamin E isomer on phosphatidylserine (PS) exposure at the surface of circulating erythrocytes, and to determine consequences on erythrocyte properties. Methods and Results— In vitro α-tocopherol enrichment of isolated erythrocytes significantly decreased PS externalization as assessed by lower Annexin V-fluorescein isothiocyanate labeling. Plasma phospholipid transfer protein (PLTP) transfers vitamin E, and both α-and γ-tocopherol accumulated in circulating erythrocytes from PLTP-deficient homozygous (PLTP −/− ) mice as compared with wild-type mice. In agreement with in vitro studies, vitamin E–enr…
Plasma phospholipid transfer protein (PLTP) modulates adaptive immune functions through alternation of T helper cell polarization
2016
International audience; Objective: Plasma phospholipid transfer protein (PLTP) is a key determinant of lipoprotein metabolism, and both animal and human studies converge to indicate that PLTP promotes atherogenesis and its thromboembolic complications. Moreover, it has recently been reported that PLTP modulates inflammation and immune responses. Although earlier studies from our group demonstrated that PLTP can modify macrophage activation, the implication of PLTP in the modulation of T-cell-mediated immune responses has never been investigated and was therefore addressed in the present study. Approach and results: In the present study, we demonstrated that PLTP deficiency in mice has a pro…
7-Ketocholesterol Incorporation into Sphingolipid/Cholesterol-enriched (Lipid Raft) Domains Is Impaired by Vitamin E
2009
Cholesterol oxides, in particular 7-ketocholesterol, are proatherogenic compounds that induce cell death in the vascular wall when localized in lipid raft domains of the cell membrane. Deleterious effects of 7-ketocholesterol can be prevented by vitamin E, but the molecular mechanism involved is unclear. In this study, unlike γ-tocopherol, the α-tocopherol vitamin E form was found to prevent 7-ketocholesterol-mediated apoptosis of A7R5 smooth muscle cells. To be operative, α-tocopherol needed to be added to the cells before 7-ketocholesterol, and its anti-apoptotic effect was reduced and even suppressed when added together or after 7-ketocholesterol, respectively. Both pre- and co-treatment…
Innate immune response triggered by triacyl lipid A is dependent on phospholipid transfer protein (PLTP) gene expression
2010
Hexaacyl lipopolysaccharide (LPS) aggregates in aqueous media, but its partially deacylated lipid A moiety forms monomers with weaker toxicity. Because plasma phospholipid transfer protein (PLTP) transfers hexaacyl LPS, its impact on metabolism and biological activity of triacyl lipid A in mice was addressed. Triacyl lipid A bound readily to plasma high-density lipoproteins (HDLs) when active PLTP was expressed [HDL-associated lipid A after 4.5 h: 59.1+/-16.0% of total in wild-type (WT) vs. 32.5+/-10.3% in PLTP-deficient mice, P0.05]. In the opposite to hexaacyl LPS, plasma residence time of lipid A was extended by PLTP, and proinflammatory cytokines were produced in higher amounts in WT th…
High Serum Cholesteryl Ester Transfer Rates and Small High-Density Lipoproteins Are Associated With Young Age in Patients With Acute Myocardial Infar…
2007
Objectives Our aim was to characterize cholesteryl ester transfer protein (CETP) activity in the early phase of acute myocardial infarction (MI). Background Cholesteryl ester transfer protein catalyzes the transfer of cholesteryl esters from high-density lipoprotein (HDL) donors to apolipoprotein B-containing lipoprotein acceptors. Methods The CETP concentration, lipid profiles, and the rate of cholesteryl ester transfer (CET) from a tracer dose of radiolabeled HDL toward endogenous lipoproteins were determined within 24 h after symptom onset. Results Among 347 patients with first MI, CETP concentration, triglycerides, and non–HDL-cholesterol increased across tertiles of the CET rate, where…
Cholesterol accumulation is increased in macrophages of phospholipid transfer protein-deficient mice: normalization by dietary alpha-tocopherol suppl…
2007
Objective— Phospholipid transfer protein (PLTP) is a multifunctional, extracellular lipid transport protein that plays a major role in lipoprotein metabolism and atherosclerosis. Recent in vivo studies suggested that unlike systemic PLTP, macrophage-derived PLTP would be antiatherogenic. The present study aimed at characterizing the atheroprotective properties of macrophage-derived PLTP. Methods and Results— Peritoneal macrophages were isolated from PLTP-deficient and wild-type mice and their biochemical characteristics were compared. It is shown that macrophages isolated from PLTP-deficient mice have increased basal cholesterol content and accumulate more cholesterol in the presence of LD…
Vitamin E transport, membrane incorporation and cell metabolism: Is α-tocopherol in lipid rafts an oar in the lifeboat?
2010
International audience; Vitamin E is composed of closely related compounds, including tocopherols and tocotrienols. Studies of the last decade provide strong support for a specific role of alpha-tocopherol in cell signalling and the regulation of gene expression. It produces significant effects on inflammation, cell proliferation and apoptosis that are not shared by other vitamin E isomers with similar antioxidant properties. The different behaviours of vitamin E isomers might relate, at least in part, to the specific effects they exert at the plasma membrane. alpha-Tocopherol is not randomly distributed throughout the phospholipid bilayer of biological membranes, and as compared with other…
Development of Abdominal Aortic Aneurysm Is Decreased in Mice with Plasma Phospholipid Transfer Protein Deficiency
2013
International audience; Plasma phospholipid transfer protein (PLTP) increases the circulating levels of proatherogenic lipoproteins, accelerates blood coagulation, and modulates inflammation. The role of PLTP in the development of abdominal aortic aneurysm (AAA) was investigated by using either a combination of mechanical and elastase injury at one site of mouse aorta (elastase model) or continuous infusion of angiotensin II in hyperlipidemic ApoE-knockout mice (Ang II model). With the elastase model, complete PLTP deficiency was associated with a significantly lower incidence and a lesser degree of AAA expansion. With the Ang II model, findings were consistent with those in the elastase mo…