Search results for "phospholipids"

Stability of liposomes composed of polymerizable and/or natural phospholipids

1989

Polysialic acid can mediate membrane interactions by interacting with phospholipids

2009

Polysialic acid (polySia) is expressed on the surface of neural cells, neuroinvasive bacterial cells and several tumor cells. PolySia chains attached to NCAM can influence both trans interactions between membranes of two cells and cis interactions. Here, we report on the involvement of phospholipids in regulation of membrane interactions by polySia. The pH at the surface of liposomes, specific molecular area of phosphatidylcholine molecules, phase transition of DPPC bilayers, cyclic voltammograms of BLMs, and electron micrographs of phosphatidylcholine vesicles were studied after addition of polysialic acid free in solution. The results indicate that polySia chains can associate with phosph…

Sphingosine-1-phosphate increases human alveolar epithelial IL-8 secretion, proliferation and neutrophil chemotaxis

2009

Sphingosine-1-phosphate (S1P) has been presented recently as a pro-inflammatory agent in the airway epithelium since S1P levels are increased in bronchoalveolar lavage fluid of human asthmatics. However, the effects of S1P over the alveolar epithelium and neutrophil interactions are poorly understood. Here, we show that S1P increased interleukin 8 (IL-8) gene expression and protein secretion and proliferation in alveolar epithelial cells A549 at physiological concentrations (1 microM). At the same time, S1P increased intracellular Ca2+ concentration (potency 17.91 microM, measured by epifluorescence microscopy), phospholipase D (PLD) activity (measured by chemiluminiscence method) and extra…

Inhaled Surfactant in the treatment of accidental Talc Powder inhalation: a new case report

2011

Abstract The use of talcum powder is incorrectly part of the traditional care of infants. Its acute aspiration is a very dangerous condition in childhood. Although the use of baby powder has been discouraged from many authors and the reports of its accidental inhalation have been ever more rare, sometimes new cases with several fatalities have been reported. We report on a patient in which accidental inhalation of baby powder induced severe respiratory difficulties. We also point out the benefits of surfactant administration. Surfactant contributed to the rapid improvement of the medical and radiological condition, preventing severe early and late complications and avoiding invasive approac…

Mechanisms underlying the toxicity of lactone aroma compounds towards the producing yeast cells

2003

M. A G U E D O , L. B E N E Y , Y. W A C H EA N D J. - M. B E L I N. 2003. Aims: To study the fundamental mechanisms of toxicity of the fruity aroma compound c-decalactone, that lead to alterations in cell viability during its biotechnological production by yeast cells; Yarrowia lipolytica that is able to produce high amounts of this metabolite was used here as a model. Methods and Results: Lactone concentrations above 150 mg l )1 inhibited cell growth, depolarized the living cells and increased membrane fluidity. Infrared spectroscopic measurements revealed that the introduction of the lactone into model phospholipid bilayers, decreased the phase transition temperature. Moreover, the H + -…

Partitioning of Pyrene-Labeled Phospho- and Sphingolipids between Ordered and Disordered Bilayer Domains

2004

AbstractHere we have studied how the length of the pyrene-labeled acyl chain (n) of a phosphatidylcholine, sphingomyelin, or galactosylceramide affects the partitioning of these lipids between 1), gel and fluid domains coexisting in bovine brain sphingomyelin (BB-SM) or BB-SM/spin-labeled phosphatidylcholine (PC) bilayers or 2), between liquid-disordered and liquid-ordered domains in BB-SM/spin-labeled PC/cholesterol bilayers. The partitioning behavior was deduced either from modeling of pyrene excimer/monomer ratio versus temperature plots, or from quenching of the pyrene monomer fluorescence by spin-labeled PC. New methods were developed to model excimer formation and pyrene lipid quenchi…

Nutriosomes: Prebiotic delivery systems combining phospholipids, a soluble dextrin and curcumin to counteract intestinal oxidative stress and inflamm…

2018

Nutriosomes, new phospholipid nanovesicles specifically designed for intestinal protection were developed by simultaneously loading a water-soluble dextrin (Nutriose® FM06) and a natural antioxidant (curcumin). Nutriosomes were easily fabricated in a one-step, organic solvent-free procedure. The stability and delivery performances of the vesicles were improved by adding hydroxypropyl methylcellulose. All the vesicles were small in size (mean diameter ∼168 nm), negatively charged (zeta potential ∼-38 mV, irrespective of their composition), and self-assembled predominantly in unilamellar vesicles stabilized by the presence of Nutriose®, which was located in both the inter-lamellar and inter-v…

Exploration of lipid metabolism in relation with plasma membrane properties of Duchenne muscular dystrophy cells: influence of L-carnitine.

2012

Duchenne muscular dystrophy (DMD) arises as a consequence of mutations in the dystrophin gene. Dystrophin is a membrane-spanning protein that connects the cytoskeleton and the basal lamina. The most distinctive features of DMD are a progressive muscular dystrophy, a myofiber degeneration with fibrosis and metabolic alterations such as fatty infiltration, however, little is known on lipid metabolism changes arising in Duchenne patient cells. Our goal was to identify metabolic changes occurring in Duchenne patient cells especially in terms of L-carnitine homeostasis, fatty acid metabolism both at the mitochondrial and peroxisomal level and the consequences on the membrane structure and functi…

Effect of the extract of Ginkgo biloba (EGb 761) on the circulating and cellular profiles of polyunsaturated fatty acids: correlation with the anti-o…

2000

Abstract Ginkgo biloba extract (EGb 761) has beneficial effects on cognitive functions in aging patients, and on various pathologies, including cardiovascular diseases. Although the extract is known to have antioxidant properties and improve membrane fluidity, the cellular mechanisms underlying these effects have not been determined. Here, we examined the in vivo effects of EGb 761 on circulating and cellular lipids. EGb 761 treatment induced significant increases in the levels of circulating polyunsaturated fatty acids (PUFAs), and a decrease in the saturation index SI (saturated/polyunsaturated species). Plasma triglycerides and cholesterol were not affected, while phospholipids were slig…

Membrane fluidity and fatty acid metabolism in kidney cells from rats fed purified eicosapentaenoic acid or purified docosahexaenoic acid

1998

Hagve T-A, Woldseth B, Brox J, Narce M, Poisson J-P. Membrane £uidity and fatty acid metabolism in kidney cells from rats fed puri¢ed eicosapentaenoic acid or puri¢ed docosahexaenoic acid. Scand J Clin Lab Invest 1998; 58: 187^194. Rats were given a supplement (1.5 ml/day) of purified eicosapentaenoic acid (EPA, 20:5,n-3), purified docosahexaenoic acid (DHA, 22:6,n-3)), or corn oil for 10 days. Membrane fluidity, measured as the steady-state fluorescence polarization of diphenylhexatriene (DPH), was approximately 20% lower in kidney cells from rats fed purified EPA than in cells from the DHA-fed or corn-oil fed animals. The level of 20:5(n-3) in kidney phospholipids was 18 times higher in r…