Search results for "QD415"
showing 10 items of 87 documents
Apolipoprotein CI is a physiological regulator of cholesteryl ester transfer protein activity in human plasma but not in rabbit plasma
2009
Plasma cholesteryl ester transfer protein (CETP) activity is high in rabbits, intermediate in humans, and nondetectable in rodents. Human apolipoprotein CI (apoCI) was found to be a potent inhibitor of CETP. The aim of this study was to compare the ability of rabbit and human apoCI to modulate the interaction of CETP with HDLs and to evaluate to which extent apoCI contributes to plasma cholesteryl ester transfer rate in normolipidemic humans and rabbits. Rabbit apoCI gene was cloned and sequenced, rabbit and human apoCI were purified to homogeneity, and their ability to modify the surface charge properties and the CETP inhibitory potential of HDL were compared. It is demonstrated that unlik…
Hibernation impact on the catalytic activities of the mitochondrial D-3-hydroxybutyrate dehydrogenase in liver and brain tissues of jerboa (Jaculus o…
2003
Abstract Background Jerboa (Jaculus orientalis) is a deep hibernating rodent native to subdesert highlands. During hibernation, a high level of ketone bodies i.e. acetoacetate (AcAc) and D-3-hydroxybutyrate (BOH) are produced in liver, which are used in brain as energetic fuel. These compounds are bioconverted by mitochondrial D-3-hydroxybutyrate dehydrogenase (BDH) E.C. 1.1.1.30. Here we report, the function and the expression of BDH in terms of catalytic activities, kinetic parameters, levels of protein and mRNA in both tissues i.e brain and liver, in relation to the hibernating process. Results We found that: 1/ In euthemic jerboa the specific activity in liver is 2.4- and 6.4- fold high…
Gene-environment interactions of CETP gene variation in a high cardiovascular risk Mediterranean population
2010
Genome-wide association studies show that cholesteryl ester transfer protein (CETP) single nucleotide polymorphisms (SNPs) are more strongly associated with HDL cholesterol (HDL-C) concentrations than any other loci across the genome. However, gene-environment interactions for clinical applications are still largely unknown. We studied gene-environment interactions between CETP SNPs and dietary fat intake, adherence to the Mediterranean diet, alcohol consumption, smoking, obesity, and diabetes on HDL-C in 4,210 high cardiovascular risk subjects from a Mediterranean population. We focused on the −4,502C>T and the TaqIB SNPs in partial linkage disequilibrium (D'= 0.88; P < 0.001). They were i…
Comparative study of serine-plasmalogens in human retina and optic nerve: identification of atypical species with odd carbon chains
2012
International audience; The objective of this work was to detect and identify phosphatidylserine plasmalogen species in human ocular neurons represented by the retina and the optic nerve. Plasmalogens (vinyl-ether bearing phospholipids) are commonly found in the forms of phosphatidylcholine and phosphatidylethanolamine in numerous mammalian cell types, including the retina. While their biological functions are still unclear, the alteration of cellular plasmalogen content has been associated with several human disorders such as Rhizomelic Chondrodysplasia Punctata Type 2 and Primary Open-Angle Glaucoma.By using liquid-chromatography coupled to high resolution and tandem mass spectrometry, we…
Docosahexaenoic acid reduces suppressive and migratory functions of CD4CD25 regulatory T-cells
2009
Immunological tolerance is one of the fundamental aspects of the immune system. The CD4(+)CD25(+) regulatory T (Treg) cells have emerged as key players in the development of tolerance to self and foreign antigens. However, little is known about the endogenous factors and mechanisms controlling their suppressive capacity on immune response. In this study, we observed that docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid, diminished, in a dose-dependent manner, the capacity of Treg cells to inhibit the CD4(+)CD25(-) effector T-cell proliferation. DHA not only reduced the migration of Treg cells toward chemokines but also downregulated the mRNA expression of CCR-4 and CXCR-4 in Tr…
Targeted profiling of circulating and hepatic bile acids in human, mouse, and rat using a UPLC-MRM-MS-validated method
2012
Bile acids (BAs) are a group of chemically related steroids recognized as regulatory molecules whose profiles can change in different physio-pathological situations. We have developed a sensitive, fast, and reproducible ultraperformance liquid chromatography/multiple reaction monitoring/mass spectrometry method to determine the tissue and sera BA profiles in different species (human, rat, and mouse) by quantifying 31 major and minor BA species in a single 21-min run. The method has been validated according to FDA guidelines, and it generally provides good results in terms of intra- and interday precision (less than 8.6% and 16.0%, respectively), accuracy (relative error measurement between …
Fatty liver in familial hypobetalipoproteinemia: triglyceride assembly into VLDL particles is affected by the extent of hepatic steatosis
2003
Familial hypobetalipoproteinemia (FHBL) subjects may develop fatty liver. Liver fat was assessed in 21 FHBL with six different apolipoprotein B (apoB) truncations (apoB-4 to apoB-89) and 14 controls by magnetic resonance spectroscopy (MRS). Liver fat percentages were 16.7 +/- 11.5 and 3.3 +/- 2.9 (mean +/- SD) (P = 0.001). Liver fat percentage was positively correlated with body mass index, waist circumference, and areas under the insulin curves of 2 h glucose tolerance tests, suggesting that obesity may affect the severity of liver fat accumulation in both groups. Despite 5-fold differences in liver fat percentage, mean values for obesity and insulin indexes were similar. Thus, for similar…
Farnesoid X receptor activation increases cholesteryl ester transfer protein expression in humans and transgenic mice
2013
International audience; Cholesteryl ester transfer protein (CETP) activity results in a proatherogenic lipoprotein profile. In cholestatic conditions, farnesoid X receptor (FXR) signaling by bile acids (BA) is activated and plasma HDL cholesterol (HDL-C) levels are low. This study tested the hypothesis that FXR-mediated induction of CETP contributes to this phenotype. Patients with cholestasis and high plasma BA had lower HDL-C levels and higher plasma CETP activity and mass compared with matched controls with low plasma BA (each P < 0.01). BA feeding in APOE3*Leiden transgenic mice expressing the human CETP transgene controlled by its endogenous promoter increased cholesterol within apoB-c…
PLTP activity is a risk factor for subsequent cardiovascular events in CAD patients under statin therapy: the AtheroGene study.
2009
Phospholipid transferprotein (PLTP) mediates both net transfer and exchange of phospholipids between different lipoproteins. Although many studies have investigated the role of PLTP in atherogenesis, the role of PLTP in atherosclerotic diseases is unclear. We investigated the association of serum PLTP activity with the incidence of a combined endpoint (myocardial infarction and cardiovascular death) and its relation to other markers of atherosclerosis in 1,085 patients with angiographically documented coronary artery disease (CAD). In the median follow-up of 5.1 years, 156 patients had suffered from the combined endpoint of myocardial infarction or cardiovascular death including 47 of 395 p…
Lipoprotein lipase-facilitated uptake of LDL is mediated by the LDL receptor
2007
LPL mediates the uptake of lipoproteins into different cell types independent of its catalytic activity. The mechanism of this process and its physiological relevance are not clear. Taking into account the importance of the endothelial barrier for lipoprotein uptake, in vitro studies with primary aortic endothelial cells from wild-type and low density lipoprotein receptor (LDLR)-deficient (LDLR(-/-)) mice were performed. Addition of LPL almost doubled the uptake of LDL into wild-type cells. However, there was virtually no LPL-mediated change of LDL uptake into LDLR(-/-) cells. Upregulation of LDLR by lipoprotein-deficient serum/lovastatin in wild-type cells resulted in a 7-fold increase of …