Search results for "Cholesterol"

Perturbed interactions of mutant proteolipid protein/DM20 with cholesterol and lipid rafts in oligodendroglia: implications for dysmyelination in spa…

2006

Missense mutations in the humanPLP1gene lead to dysmyelinating diseases with a broad range of clinical severity, ranging from severe Pelizaeus–Merzbacher disease (PMD) to milder spastic paraplegia type 2 (SPG-2). The molecular pathology has been generally attributed to endoplasmic reticulum (ER) retention of misfolded proteolipid protein (PLP) (and its splice isoform DM20) and induction of the unfolded protein response. As opposed to previous studies of heterologous expression systems, we have analyzed PLP/DM20 trafficking in oligodendroglial cells, thereby revealing differences between PMD and SPG-2-associated PLP/DM20 isoforms. PLPA242Vand DM20A242V(jimpy-msdin mice), associated with seve…

7keto-stigmasterol and 7keto-cholesterol induce differential proteome changes to intestinal epitelial (Caco-2) cells

2015

Abstract Recent studies have expanded the appreciation of the roles of oxysterols triggering inflammatory, immune cytotoxic and apoptotic processes, but have not been considered for proteome analysis. A comparative proteomic study in intestinal epithelial cell cultures incubated (60 μM/24 h) with 7keto-cholesterol or 7keto-stigmasterol was performed. The influence of both compounds was studied following the nLC-TripleTOF analysis. Findings were compared to results for control cultures. In the principal component analysis (PCA) of proteome patterns, two components were extracted accounting for 99.8% of the variance in the protein expression. PCA analysis clearly discriminated between the per…

Versatile, sensitive liquid chromatography mass spectrometry – Implementation of 10 μm OT columns suitable for small molecules, peptides and proteins

2016

AbstractWe have designed a versatile and sensitive liquid chromatographic (LC) system, featuring a monolithic trap column and a very narrow (10 μm ID) fused silica open tubular liquid chromatography (OTLC) separation column functionalized with C18-groups, for separating a wide range of molecules (from small metabolites to intact proteins). Compared to today’s capillary/nanoLC approaches, our system provides significantly enhanced sensitivity (up to several orders) with matching or improved separation efficiency, and highly repeatable chromatographic performance. The chemical properties of the trap column and the analytical column were fine-tuned to obtain practical sample loading capacities…

A potential link between serum low-density lipoproteins and asthma

2015

The ins and outs of cholesterol in the vertebrate retina

2010

Thematic Review Series: Lipids and Lipid Metabolism in the Eye; International audience; The vertebrate retina has multiple demands for utilization of cholesterol and must meet those demands either by synthesizing its own supply of cholesterol or by importing cholesterol from extraretinal sources, or both. Unlike the blood-brain barrier, the blood-retina barrier allows uptake of cholesterol from the circulation via a lipoprotein-based/receptor-mediated mechanism. Under normal conditions, cholesterol homeostasis is tightly regulated; also, cholesterol exists in the neural retina overwhelmingly in unesterified form, and sterol intermediates are present in minimal to negligible quantities. Howe…

Low physical activity and its association with diabetes and other cardiovascular risk factors: a nationwide, population-based study

2016

Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM; ISCIII Ministerio de Ciencia e Innovacion); Ministerio de Sanidad y Consumo; Spanish Diabetes Society (SED)

Hepatic farnesyl diphosphate synthase expression is suppressed by polyunsaturated fatty acids

2005

Dietary vegetable oils and fish oils rich in PUFA (polyunsaturated fatty acids) exert hypocholesterolaemic and hypotriglyceridaemic effects in rodents. The plasma cholesterol-lowering properties of PUFA are due partly to a diminution of cholesterol synthesis and of the activity of the rate-limiting enzyme HMG-CoA reductase (3-hydroxy-3-methylglutaryl-CoA reductase). To better understand the mechanisms involved, we examined how tuna fish oil and individual n−3 and n−6 PUFA affect the expression of hepatic FPP synthase (farnesyl diphosphate synthase), a SREBP (sterol regulatory element-binding protein) target enzyme that is subject to negative-feedback regulation by sterols, in co-ordination …

Factors affecting the amount and the mode of merocyanine 540 binding to the membrane of human erythrocytes. A comparison with the binding to leukemia…

1995

Abstract In the presence of albumin Merocyanine 540 (MC540) exhibits a very limited binding to the outer surface of the membrane of normal erythrocytes, whereas pronounced binding is observed to leukemia cells. To find out whether this difference is due to differences in the composition or structural organization of the cell membrane we analyzed effects of a number of covalent and non-covalent perturbations of the red cell membrane on the binding and fluorescence characteristics of membrane-bound MC540. It is shown that exposure of the cells to cationic chlorpromazine, neuraminidase or photodynamic treatment with AlPcS 4 as sensitizer caused a limited increase (30–50%) of MC540 binding, tog…

Statins and peripheral arterial disease: effects on claudication, disease progression, and prevention of cardiovascular events.

2006

Peripheral arterial disease (PAD) of the lower limbs is the third most important site of atherosclerotic disease alongside coronary heart disease (CHD) and cerebrovascular disease (CVD). Best medical treatment is beneficial even in patients who eventually need invasive treatment, as the safety, immediate success, and durability of intervention is greatly improved in patients who adhere to best medical treatment. In recent years, a number of studies have suggested that the ACE-inhibitor ramipril and different statins, together with antiplatelet drugs, reduce cardiovascular morbidity and mortality in PAD. Patients with PAD are really a category of patients with a very high cardiovascular risk…

Species-specific mechanisms for cholesterol 7alpha-hydroxylase (CYP7A1) regulation by drugs and bile acids.

2005

The gene encoding cholesterol 7alpha-hydroxylase (CYP7A1) is tightly regulated in order to control intrahepatic cholesterol and bile acid levels. Ligands of the xenobiotic-sensing pregnane X receptor inhibit CYP7A1 expression. To retrace the evolution of the molecular mechanisms underlying CYP7A1 inhibition, we used a chicken hepatoma cell system that retains the ability to be induced by phenobarbital and other drugs. Whereas bile acids regulate CYP7A1 via small heterodimer partner and liver receptor homolog-1, mRNA expression of these nuclear receptors is unchanged by xenobiotics. Instead, drugs repress chicken hepatic nuclear factor 4alpha (HNF4alpha) transcript levels concomitant with a …