Search results for "Lip"

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…

Hidden complexity in membrane permeabilization behavior of antimicrobial polycations.

2021

A promising alternative to classical antibiotics are antimicrobial peptides and their synthetic mimics (smAMPs) that supposedly act directly on membranes. For a more successful design of smAMPs, we need to know how the type of interaction with the membrane determines the type of membrane perturbation. How this, in turn, transfers into selectivity and microbial killing activity is largely unknown. Here, we characterize the action of two smAMPs: MM:CO (a copolymer of hydrophobic cyclooctyl subunits and charged β-monomethyl-α-aminomethyl subunits) and the highly charged poly-NM (a homopolymer of α-aminomethyl subunits). By thorough characterization of vesicle leakage experiments, we elucidate …

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.

LC‐ESI / HRMS analysis of glucosinolates, oxylipins and phenols in Italian rocket salad ( Diplotaxis erucoides subsp. erucoides (L.) DC .) and evalua…

2021

BACKGROUND This study investigated the chemical profile and biological activity of Diplotaxis erucoides subsp. erucoides (L.) DC. (Brassicaceae) collected in Sicily (Italy). RESULTS Liquid chromatography coupled with electrospray ionization and high-resolution mass spectrometry (LC-ESI/HRMS) analysis of the ethanol extract revealed the presence of 42 compounds - glucosinolates, hydroxycinnamic acids, flavonoids, and oxylipins. The extract was tested for its antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic) acid (ABTS), ferric reducing ability power (FRAP), and β-carotene bleaching tests. Promising protection from lipid peroxida…

P059 Le lipido-récepteur intestinal CD36 et sa cascade de signalisation ERK1/2 dépendante contrôle la synthèse des chylomicrons

2013

International audience; Introduction et but de l’étude. – L’intestin est capable d’adapter sa capacité d’absorption à la teneur en lipide du régime. Cette adaptation implique un système de détection des lipides au niveau entérocytaire. Le CD36, qui est une glycoprotéine transmembranaire liant avec une forte affinité les acides gras à longue chaîne (AGLC), pourrait jouer ce rôle. En effet, ex vivo, la présence d’AGLC est associée à une activation de la voie ERK1/2 et conduit à l’induction de protéines clés du métabolisme intestinal des lipides : l’ApoB48 et la MTP. Cette régulation est CD36 dépendante (Tran et al. 2011). De plus, la déficience de CD36 est associée chez l’Homme et l’animal à …

Crustacean Hemolymph Lipoproteins

2020

Lipoproteins mediate the transport of apolar lipids in the hydrophilic environment of physiological fluids such as the vertebrate blood and the arthropod hemolymph. In this overview, we will focus on the hemolymph lipoproteins in Crustacea that have received most attention during the last years: the high density lipoprotein/β-glucan binding proteins (HDL-BGBPs), the vitellogenins (VGs), the clotting proteins (CPs) and the more recently discovered large discoidal lipoproteins (dLPs). VGs are female specific lipoproteins which supply both proteins and lipids as storage material for the oocyte for later use by the developing embryo. Unusual within the invertebrates, the crustacean yolk protein…

Disarrangement of Endoplasmic reticulum-mitochondria communication impairs Ca2+ homeostasis in FRDA

2020

AbstractFriedreich ataxia (FRDA) is a neurodegenerative disorder characterized by neuromuscular and neurological manifestations. It is caused by mutations in gene FXN, which results in loss of the mitochondrial protein frataxin. Endoplasmic Reticulum-mitochondria associated membranes (MAMs) are inter-organelle structures involved in the regulation of essential cellular processes, including lipid metabolism and calcium signaling. In the present study, we have analyzed in both, unicellular and multicellular models of FRDA, an analysis of calcium management and of integrity of MAMs. We observed that function of MAMs is compromised in our cellular model of FRDA, which was improved upon treatmen…