Search results for "Athérosclérose"
showing 6 items of 6 documents
Brain Control of Plasma Cholesterol Involves Polysialic Acid Molecules in the Hypothalamus
2017
IF 3.566; International audience; The polysialic acid (PSA) is a large glycan that is added to cell-surface proteins during their post-translational maturation. In the brain, PSA modulates distances between cells and controls the plasticity of the nervous system. In the hypothalamus, PSA is involved in many aspects of energy balance including food intake, osmoregulation, circadian rhythm, and sleep. In this work, we investigated the role of hypothalamic PSA in the regulation of plasma cholesterol levels and distribution. We report that HFD consumption in mice rapidly increased plasma cholesterol, including VLDL, LDL, and HDL-cholesterol. Although plasma VLDL-cholesterol was normalized withi…
Caractérisation des figures myéliniques associées à l'accumulation de lipides polaires induites par différents oxystérols cytotoxiques identifiés dan…
2006
Atherosclerosis is a complex and chronic arterial process which is characterized by a remodeling of the vascular wall, associated with inflammatory reactions, proliferation and cell death process, and with accumulation of oxidized lipids among which oxysterols (cholesterol oxidation products) which might play key roles in the initiation and development of atheromatous lesions. Our work performed on U937 and THP1 promonocytic cells, rat aorta embryonic A7R5 cells, and breast carcinoma MCF7 cells (caspase-3 deficient). Different oxysterols, present in large quantity in atheromatous lesions, were used: 7-cétocholestérol (7KC), 7Β-hydroxycholestérol, 25-hydroxycholestérol, cholestérol-5Α, 6Α-ep…
Modulation of dendritic cells and macrophages : implication in cancer and atherosclerosis
2010
During my thesis, I studied the cytotoxic function of dendritic cells (DC) from cancer patients and compared it to DC from healthy donors. Our results indicate that human monocyte-derived DC can acquire strong cytotoxic activity toward tumor cells after activation with low dose of LPS. The cytotoxic potential of DC derived from cancer patients was almost the same as the one generated from healthy donors. We identified the tumor cell killing mechanism which involves peroxynitrite release. After killing of cancer cells, DC are capable of engulfing dead tumor cell fragments and overexpress the costimulatory molecules necessary for T cell proliferation. A second study consisted in an analysis o…
Lipid profiling following intake of the Omega 3 fatty acid DHA identifies the peroxidized metabolites F-4-Neuroprostanes as the best predictors of at…
2014
International audience; The anti-atherogenic effects of omega 3 fatty acids, namely eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) are well recognized but the impact of dietary intake on bioactive lipid mediat or profiles remains unclear. Such a profiling effort may offer novel targets for future studies into the mechanism of action of omega 3 fatty acids. The present study aimed to determine the impact of DHA supplementation on the profiles of polyunsaturated fatty acids (PUFA) oxygenated metabolites and to investigate their contribution to therosclerosis prevention. A special emphasis was given to the non-enzymatic metabolites knowing the high susceptibility of DHA to free radical…
Etude du rôle du récepteur nucléaire CAR, Constitutive Androstane Receptor, dans le métabolisme des lipides et la susceptibilité à l'athérosclérose
2011
The Constitutive Androstane Receptor (CAR) belongs to the subfamily of nuclear receptors NR1. Initially described as an orphan receptor, CAR is activated by a large number of exogenous molecules and acts as a xenosensor. The activation of CAR by these ligands stimulates transcription of phase I, II and III enzymes required for the detoxification and elimination of xenobiotics. Furthermore CAR is also involved in the metabolism of endogenous molecules such as bile acids, bilirubin or thyroid hormones. CAR has recently been the subject of numerous independent studies that have highlighted his involvement in major metabolic pathways including gluconeogenesis, lipogenesis and lipoprotein metabo…
Cellular metabolic alteration : the voice of monoinsaturated fatty acid as therapeutic target
2010
Stearoyl Co-A desaturase (SCD) is the key enzyme of the metabolism of mono-unsaturated fatty acids (MUFA). Its activity 9 desaturase introduces a double bond cis in position 9 of saturated fatty acids (SFA), induced formation of MUFA. Impaired biosynthesis of MUFA is involved in many diseases such as cancer and cardiovascular disease. Cancer cells have a de novo synthesis of fatty acids increased with an accumulation MUFA. This change in the metabolism of fatty acids is associated with overexpression SCD1 which catalyzes the conversion of saturated fatty acids, monounsaturated fat. Several reports have shown that inhibition of SCD1 leads to blockage of proliferation and induction of apopt…