Search results for "lipid"

A Bimolecular Multicellular Complementation System for the Detection of Syncytium Formation: A New Methodology for the Identification of Nipah Virus …

2019

Fusion of viral and cellular membranes is a key step during the viral life cycle. Enveloped viruses trigger this process by means of specialized viral proteins expressed on their surface, the so-called viral fusion proteins. There are multiple assays to analyze the viral entry including those that focus on the cell-cell fusion induced by some viral proteins. These methods often rely on the identification of multinucleated cells (syncytium) as a result of cell membrane fusions. In this manuscript, we describe a novel methodology for the study of cell-cell fusion. Our approach, named Bimolecular Multicellular Complementation (BiMuC), provides an adjustable platform to qualitatively and quanti…

Liver X Receptor–Mediated Induction of Cholesteryl Ester Transfer Protein Expression Is Selectively Impaired in Inflammatory Macrophages

2009

Objective— Cholesteryl ester transfer protein (CETP) is a target gene for the liver X receptor (LXR). The aim of this study was to further explore this regulation in the monocyte-macrophage lineage and its modulation by lipid loading and inflammation, which are key steps in the process of atherogenesis. Methods and Results— Exposure of bone marrow–derived macrophages from human CETP transgenic mice to the T0901317 LXR agonist increased CETP, PLTP, and ABCA1 mRNA levels. T0901317 also markedly increased CETP mRNA levels and CETP production in human differentiated macrophages, whereas it had no effect on CETP expression in human peripheral blood monocytes. In inflammatory mouse and human mac…

2021

The hydrophobic tails of aliphatic primary alcohols do insert into the hydrophobic core of a lipid bilayer. Thereby, they disrupt hydrophobic interactions between the lipid molecules, resulting in a decreased lipid order, i.e., an increased membrane fluidity. While aromatic alcohols, such as 2-phenylethanol, also insert into lipid bilayers and disturb the membrane organization, the impact of aromatic alcohols on the structure of biological membranes, as well as the potential physiological implication of membrane incorporation has only been studied to a limited extent. Although diverse targets are discussed to be causing the bacteriostatic and bactericidal activity of 2-phenylethanol, it is …

O04 Le sensing intestinal des lipides alimentaires médié par CD36 est-il altéré en cas de syndrome métabolique ?

2013

International audience; [Pas de résumé]

Sustained activation of sphingomyelin synthase by 2-hydroxyoleic acid induces sphingolipidosis in tumor cells

2013

The mechanism of action of 2-hydroxyoleic acid (2OHOA), a potent antitumor drug, involves the rapid and specific activation of sphingomyelin synthase (SMS), leading to a 4-fold increase in SM mass in tumor cells. In the present study, we investigated the source of the ceramides required to sustain this dramatic increase in SM. Through radioactive and fluorescent labeling, we demonstrated that sphingolipid metabolism was altered by a 24 h exposure to 2OHOA, and we observed a consistent increase in the number of lysosomes and the presence of unidentified storage materials in treated cells. Mass spectroscopy revealed that different sphingolipid classes accumulated in human glioma U118 cells af…

2019

Mitochondria have been increasingly recognized as a central regulatory nexus for multiple metabolic pathways, in addition to ATP production via oxidative phosphorylation (OXPHOS). Here we show that inducing mitochondrial DNA (mtDNA) stress in Drosophila using a mitochondrially-targeted Type I restriction endonuclease (mtEcoBI) results in unexpected metabolic reprogramming in adult flies, distinct from effects on OXPHOS. Carbohydrate utilization was repressed, with catabolism shifted towards lipid oxidation, accompanied by elevated serine synthesis. Cleavage and translocation, the two modes of mtEcoBI action, repressed carbohydrate rmetabolism via two different mechanisms. DNA cleavage activ…

Pantethine Alters Lipid Composition and Cholesterol Content of Membrane Rafts, With Down-Regulation of CXCL12-Induced T Cell Migration

2015

Pantethine, a natural low-molecular-weight thiol, shows broad activity in a large range of essential cellular pathways. It has been long known as a hypolipidemic and hypocholesterolemic agent. We showed recently that it exerts a neuroprotective action in mouse models of cerebral malaria and Parkinson's disease through multiple mechanisms. In the present study we looked at its effects on membrane lipid rafts that serve as platforms for molecules engaged in cell activity, therefore providing a target against inappropriate cell response leading to chronic inflammation. We found that pantethine-treated cells showed a significant change in raft fatty acid composition and cholesterol content, wit…

Wild apple (Malus spp.) by-products as a source of phenolic compounds and vitamin C for food applications

2020

Abstract The phytochemical profile and positive health effects of the fruits and by-products of domesticated Malus domestica Borkh. apple cultivars have been extensively investigated. The present study was designed to evaluate the hydrophilic composition and antioxidant activity of the compounds recovered from wild apple Malus spp. by-products. The phytochemical analysis of the 30 and 96% ethanolic extracts using LC-DAD-ESI-MS/MS has led to the detection and isolation of 25 hydrophilic compounds. Amongst the polyphenols, chlorogenic acid, B-type procyanidins, and phloretin-2-glucoside dominated. The results of HPLC-DPPH• radical scavenging showed that the major contributors to the antioxida…

PspA adopts an ESCRT-III-like fold and remodels bacterial membranes

2021

Summary PspA is the main effector of the phage shock protein (Psp) system and preserves the bacterial inner membrane integrity and function. Here, we present the 3.6 A resolution cryoelectron microscopy (cryo-EM) structure of PspA assembled in helical rods. PspA monomers adopt a canonical ESCRT-III fold in an extended open conformation. PspA rods are capable of enclosing lipids and generating positive membrane curvature. Using cryo-EM, we visualized how PspA remodels membrane vesicles into μm-sized structures and how it mediates the formation of internalized vesicular structures. Hotspots of these activities are zones derived from PspA assemblies, serving as lipid transfer platforms and lin…

P073 L’obésité diminue, de manière réversible, la préférence pour les lipides alimentaires chez la souris

2013

International audience; Introduction et but de l’étude. – Au cours des dernières années, il a été suggéré l’existence d’un lien étroit entre la détection oro-sensorielle des lipides alimentaire, la régulation de la prise alimentaire et l’IMC. Toutefois, les mécanismes affectant la sensibilité aux lipides ainsi que l’éventuelle implication directe de l’obésité restent mal connus.