Search results for "Scavenger"
showing 10 items of 129 documents
The effects of nitric oxide on striatal serotoninergic transmission involve multiple targets: an in vivo microdialysis study in the awake rat
2004
Abstract The role of endogenous nitric oxide (NO) in N -methyl- d -aspartate (NMDA)-induced modulation of serotonin (5-HT) release in the striatum of freely moving rats has been studied using microdialysis technique. NMDA-induced increase in 5-HT release was significantly inhibited by selective nitric oxide synthase (nNOS) inhibitor S -methylthiocitrulline (S-Me-TC), ONOO − scavenger l -cysteine ( l -cys), and guanylate cyclase (GC) inhibitor 1 H [1,2,4]oxadiazolo[4,3- a ]quinoxalin-1-one (ODQ). These data suggest that modulation of 5-HT levels is linked to the formation of NO produced by NMDA receptor activation and that endogenously produced NO increases 5-HT concentrations both by stimul…
Even free radicals should follow some rules: a guide to free radical research terminology and methodology.
2014
Free radicals and oxidants are now implicated in physiological responses and in several diseases. Given the wide range of expertise of free radical researchers, application of the greater understanding of chemistry has not been uniformly applied to biological studies. We suggest that some widely used methodologies and terminologies hamper progress and need to be addressed. We make the case for abandonment and judicious use of several methods and terms and suggest practical and viable alternatives. These changes are suggested in four areas: use of fluorescent dyes to identify and quantify reactive species, methods for measurement of lipid peroxidation in complex biological systems, claims of…
CD36 as a lipid sensor
2011
International audience; CD36 is a multifunctional protein homologous to the class B scavenger receptor SR-B1 mainly found in tissues with a sustained lipid metabolism and in several hematopoieic cells. CD36 is thought to be involved in various physiological and pathological processes like angiogenesis, thrombosis, atherogenesis, Alzheimer's disease or malaria. An additive emerging function for CD36 is a role as a lipid sensor. Location of CD36 and orthologue molecules in plasma membrane of cells in contact with the external environment (e.g. gustatory, intestinal or olfactory epithelia) allows the binding of exogenous-derived ligands including dietary lipids, diglycerides from bacterial wal…
Thermodynamics of competing oxidation reactions of allyl methyl disulfide by hydrogen peroxide: a first principle molecular computational study on th…
2008
Allyl methyl disulfide, a peroxide scavenger, was studied together with three isomeric (two sulfoxides and one epoxide) forms of its mono-oxidized products. After a full conformational study of the reactant and three isomeric oxidized forms, the geometries were optimized at B3LYP/6-31G (d) level of theory. The epoxide form turned and to be more stable than either one of the two isomeric sulfoxides. Changes for Thermodynamic functions of oxidation reactions were calculated and from the δGreaction values the equilibrium constant for the interconversions of the oxidized products were estimated. Bader-type AIM analyses were performed on the electron density, computed at the B3LYP/6-311++G (d,p)…
Winter movement patterns of a globally endangered avian scavenger in south-western Europe
2020
AbstractPartial migration, whereby some individuals migrate and some do not, is relatively common and widespread among animals. Switching between migration tactics (from migratory to resident or vice versa) occurs at individual and population levels. Here, we describe for the first time the movement ecology of the largest wintering population of Egyptian Vultures (Neophron percnopterus) in south-west Europe. We combined field surveys and GPS tracking data from December to February during four wintering seasons (2014–2018). The wintering population consisted on average of 85 individuals (range 58–121; 76% adults and 24% subadults). Individuals were counted at five different roosting sites lo…
Palmitoylethanolamide Promotes a Proresolving Macrophage Phenotype and Attenuates Atherosclerotic Plaque Formation
2018
Objective— Palmitoylethanolamide is an endogenous fatty acid mediator that is synthetized from membrane phospholipids by N -acyl phosphatidylethanolamine phospholipase D. Its biological actions are primarily mediated by PPAR-α (peroxisome proliferator-activated receptors α) and the orphan receptor GPR55. Palmitoylethanolamide exerts potent anti-inflammatory actions but its physiological role and promise as a therapeutic agent in chronic arterial inflammation, such as atherosclerosis remain unexplored. Approach and Results— First, the polarization of mouse primary macrophages towards a proinflammatory phenotype was found to reduce N -acyl phosphatidylethanolamine phospholipase D expression …
Kinetics of the lipoperoxyl radical-scavenging activity of indicaxanthin in solution and unilamellar liposomes
2007
Abstract The reaction of the phytochemical indicaxanthin with lipoperoxyl radicals generated in methyl linoleate methanol solution by 2,20-azobis(2,4-dimethylvaleronitrile), and in aqueous soybean phosphatidylcholine unilamellar liposomes by 2,20-azobis(2- amidinopropane)hydrochloride, was studied. The molecule acts as a chain-terminating lipoperoxyl radical scavenger in solution, with a calculated inhibition constant of 3.63 £ 105M21 s21, and a stoichiometric factor approaching 2. Indicaxanthin incorporated in liposomes prevented lipid oxidation, inducing clear-cut lag periods and decrease of the propagation rate. Both effects were concentration-dependent, but not linearly related to the p…
N-3 fatty acids modulate antioxidant status in diabetic rats and their macrosomic offspring.
2006
We investigated the role of dietary n-3 polyunsaturated fatty acids (n-3 PUFA) in the modulation of total antioxidant status in streptozotocin (STZ)-induced diabetic rats and their macrosomic offspring. Female wistar rats, fed on control diet or n-3 PUFA diet, were rendered diabetic by administration of five mild doses of STZ on day 5 and were killed on days 12 and 21 of gestation. The macrosomic (MAC) pups were killed at the age of 60 and 90 days. Lipid peroxidation was measured as the concentrations of plasma thiobarbituric acid reactive substances (TBARS), and the total antioxidant status was determined by measuring (i) plasma oxygen radical absorbance capacity (ORAC), (ii) plasma vitami…
Inhibition of induced DNA oxidative damage by beers: correlation with the content of polyphenols and melanoidins.
2005
Beers are a source of dietary flavonoids; however, there exist differences in composition, alcohol concentration, and beneficial activities. To characterize these differences, three kinds of lager beer of habitual consumption in Spain, dark, blond, and alcohol-free, were assayed for total phenolic content, antioxidant activity, superoxide and hydroxyl radical scavenging activities, and in vitro inhibitory effect on DNA oxidative damage. Furthermore, their melanoidin content and correlation with antioxidant activity were evaluated. Dark beer contained the highest total phenolic (489 +/- 52 mg/L) and melanoidin (1.49 +/- 0.02 g/L) contents with a 2-fold difference observed when compared to th…
eNOS Activation by HDL Is Impaired in Genetic CETP Deficiency.
2014
Mutations in the CETP gene resulting in defective CETP activity have been shown to cause remarkable elevations of plasma HDL-C levels, with the accumulation in plasma of large, buoyant HDL particles enriched in apolipoprotein E. Genetic CETP deficiency thus represents a unique tool to evaluate how structural alterations of HDL impact on HDL atheroprotective functions. Aim of the present study was to assess the ability of HDL obtained from CETP-deficient subjects to protect endothelial cells from the development of endothelial dysfunction. HDL isolated from one homozygous and seven heterozygous carriers of CETP null mutations were evaluated for their ability to down-regulate cytokine-induced…