Search results for "FATTY ACIDS"
showing 10 items of 719 documents
Preparation and evaluation of lauryl methacrylate monoliths with embedded silver nanoparticles for capillary electrochromatography
2012
In this article, capillary columns constituted by lauryl methacrylate monoliths with embedded silver nanoparticles (AgNPs) were developed and tested. Two incorporation approaches of AgNPs in monoliths were explored. The AgNPs were either photogenerated in situ during polymerization of the monolith by UV irradiation, or incorporated to the polymerization mixture (ex situ). The influence of the AgNP concentration on the morphological and chromatographic properties of the polymer matrix was investigated, and both the in situ and ex situ approaches were comparatively discussed. The morphology of the monoliths was characterized by electron microscopic techniques, and their electrochromatographic…
Induction of cholesterol biosynthesis by archazolid B in T24 bladder cancer cells.
2014
Abstract Background Resistance of cancer cells towards chemotherapeutics represents a major cause of therapy failure. The objective of our study was to evaluate cellular defense strategies in response to the novel vacuolar H+-ATPase inhibitor, archazolid B. Experimental approach: The effects of archazolid B on T24 bladder carcinoma cells were investigated by combining “omics” technologies (transcriptomics (mRNA and miRNA) and proteomics). Free cholesterol distribution was determined by filipin staining using flow cytometry and fluorescence microscopy. Flow cytometry was performed for LDLR surface expression studies. Uptake of LDL cholesterol was visualized by confocal microscopy. SREBP acti…
Fluvastatin stabilizes the blood–brain barrier in vitro by nitric oxide-dependent dephosphorylation of myosin light chains
2006
Inhibition of the 3-hydroxy-3-methylglutaryl-coenzyme-A reductase and the downstream mevalonate pathway is in part responsible for the beneficial effects that statins exert on the cardiovascular system. In this study we aimed at analysing the stabilizing effects of fluvastatin on the blood-brain barrier (BBB) integrity, using an in vitro co-culture model of ECV304 and C6, or primary bovine endothelial cells and rat astrocytes. Fluvastatin dose-dependently (1-25 micromol/l) increased barrier integrity as analysed by measurements of transendothelial electrical resistance (TEER). This effect (117.4+/-2.6% at 25 micromol/l) was significantly reduced by the nitric oxide (NO) synthase inhibitor L…
Fluvastatin prevents glutamate-induced blood-brain-barrier disruption in vitro.
2008
Abstract Glutamate is an important excitatory amino acid in the central nervous system. Under pathological conditions glutamate levels dramatically increase. Aim of the present study was to examine whether the HMG-CoA inhibitor fluvastatin prevents glutamate-induced blood-brain-barrier (BBB) disruption. Measurements of transendothelial electrical resistance (TEER) were performed to analyze BBB integrity in an in vitro co-culture model of brain endothelial and glial cells. Myosin light chain (MLC) phosphorylation was detected by immunohistochemistry, or using the in-cell western technique. Intracellular Ca 2+ and reactive oxygen species (ROS) levels were analyzed using the fluorescence dyes …
Diacylglycerols containing Omega 3 and Omega 6 fatty acids bind to RasGRP and modulate MAP kinase activation.
2003
We elucidated the effects of different diacylglycerols (DAGs), i.e. 1-stearoyl-2-arachidonoyl-sn-glycerol (SAG), 1-stearoyl-2-docosahexaenoyl-sn-glycerol (SDG), and 1-stearoyl-2-eicosapentaenoyl-sn-glycerol (SEG), on [3H]PDBu binding to RasGRP. The competition studies with these DAGs on [3H]PDBu binding to RasGRP revealed different Ki values for these DAG molecular species. Furthermore, we transfected human Jurkat T cells by a plasmid containing RasGRP and assessed the implication of endogenous DAGs on activation of MAP kinases ERK1/ERK2, induced by phorbol-12-myristate-13-acetate (PMA). In control cells, GF109203X, a protein kinase C inhibitor, inhibited ERK1/ERK2 activation. However, this…
Pharmacodynamic approach to study the gene transfer process employing non-viral vectors
2000
Abstract In the present work we set out to apply pharmacodynamic concepts derived from dose–response curves (Potency and Efficacy) to characterize the gene transfer efficiency of a vector:DNA complex. We employed two widely used vectors, the cationic lipid DOTAP (N,N,N-trimethyl 1-2-3-bis (1-oxo-9-octa-decenyl)oxy-(Z,Z)-1-propanaminium methyl sulfate) and the cationic polymer PEI (polyethylenimine, 800 kDa) to transfect several constructions of the green fluorescent protein cDNA. The analysis of dose–response curves indicated that in all cases the goodness-of-fit was > 0.99. Potency is a measure that provides information on gene activity per amount of DNA. Efficacy is a measure of maximum g…
Fast and direct analysis of oxidation levels of oil-in-water emulsions using ATR-FTIR.
2019
International audience; Oxidation of omega-3 fatty acids is a major limitation on its enrichment in food and beverages. An efficient and simple method to monitor lipid oxidation in complex systems is essential to limit lipid oxidation during formulation and processing. Fish oil-in-water emulsions (20% v/v) were exposed to iron or free radical initiated oxidation. Conjugated dienes (CDs) were rapidly measured using a previously developed fat extraction method. Fourier transform infrared (FTIR) spectroscopy has been used to directly record chemical changes occurring during oxidation. Variations were noticed in different spectral regions despite the presence of broad water bands near 3400 and …
Unsaturated Fatty Acids Drive Disintegrin and Metalloproteinase (ADAM)-dependent Cell Adhesion, Proliferation, and Migration by Modulating Membrane F…
2011
The disintegrin-metalloproteinases ADAM10 and ADAM17 mediate the release of several cell signaling molecules and cell adhesion molecules such as vascular endothelial cadherin or L-selectin affecting endothelial permeability and leukocyte transmigration. Dysregulation of ADAM activity may contribute to the pathogenesis of vascular diseases, but the mechanisms underlying the control of ADAM functions are still incompletely understood. Atherosclerosis is characterized by lipid plaque formation and local accumulation of unsaturated free fatty acids (FFA). Here, we show that unsaturated FFA increase ADAM-mediated substrate cleavage. We demonstrate that these alterations are not due to genuine ch…
Automated untargeted stable isotope assisted lipidomics of liver cells on high glucose shows alteration of sphingolipid kinetics
2020
Abstract Untargeted lipidomics is a powerful tool to discover new biomarkers and to understand the physiology and pathology of lipids. The use of stable isotopes as tracers to investigate the kinetics of lipids is another tool able to supply dynamic information on lipid synthesis and catabolism. Coupling the two methodology is then very appealing in the study of lipid metabolism. The main issue to face is to perform thousands of calculations in order to obtain kinetic parameters starting from the MS raw data. An automated computerized routine able to do accomplish such task is presented in this paper. We analyzed the lipid kinetics of palmitic acid (PA) in hepatoma liver cells cultured in v…
Structural differences of prebiotic oligosaccharides influence their capability to enhance iron absorption in deficient rats
2014
This study evaluates the influence of novel galacto-oligosaccharides derived from lactulose (GOS-Lu), kojibiose or 4′-galactosyl-kojibiose in hematological parameters of Fe homeostasis using Fe-deficient animals. Liver TfR-2, IL-6, NFκB and PPAR-γ expression (mRNA) were also determined by RT-qPCR analyses, and active hepcidin peptide production and short chain fatty acids by LC coupled to MS/MS or UV detection. Feeding animals with GOS-Lu or kojibiose together with FeCl3 increased hemoglobin (Hb) production (by 17%) and mean Hb concentration into erythrocytes relative to animals administered with FeCl3 alone (14.1% and 19.7%, respectively). Animals administered with prebiotics showed decrea…