Search results for " A2"
showing 10 items of 160 documents
Topical application of the adenosine A2Areceptor agonist CGS-21680 prevents phorbol-induced epidermal hyperplasia and inflammation in mice
2014
The nucleoside adenosine is a known regulator of immunity and inflammation that mediates, at least in part, the anti-inflammatory effect of methotrexate, an immunosuppressive agent widely used to treat autoimmune inflammatory diseases. Adenosine A2A receptors play a key role in the inhibition of the inflammatory process besides promoting wound healing. Therefore, we aimed to determine the topical effect of a selective agonist, CGS-21680, on a murine model of skin hyperplasia with a marked inflammatory component. Pretreatment with either CGS-21680 (5 μg per site) or the reference agent dexamethasone (200 μg/site) prevented the epidermal hyperplasia and inflammatory response induced by topica…
Sequential release of TNFα and phospholipase A2 in a rat model of LPS-induced pleurisy
1997
The levels of extracellular phospholipase A2(sPLA2) and TNFα, and cell accumulation were measured in the pleural washings obtained at different times following the induction ofEscherichia colilipopolysaccharide (LPS, 100 μg/cavity) pleurisy in rats. TNFα peaked at 2 hours (3036 ± 160.3 units/ml) and decreased thereafter. Conversely, levels of sPLA2peaked at 48 hours (1.97 ± 0.64 ng/ml) and were increased further (14.02 ± 4.16 ng/ml) by pretreatment with anti-TNFα antibody. Cell accumulation was not affected by antibody pretreatment. These data indicate that the sPLA2enzyme is involved in LPS-induced pleurisy. The enzyme seems not to be stimulated by TNFα which may be involved in the downreg…
Uneven modulation of the annexin 1 system in osteoblast-like cells by dexamethasone
2007
AbstractWe tested whether glucocorticoids modulated osteoblast expression of the annexin 1 system, including the ligand and two G-coupled receptors termed formyl-peptide receptor (FPR) and FPR-like-1 (FPRL-1). In Saos-2 cells, rapid up-regulation of FPR mRNA upon cell incubation with dexamethasone (0.01–1μM) was observed, with significant changes as early as 2h and a more marked response at 24h; annexin 1 and FPRL-1 mRNA changes were more subtle. At the protein level, dexamethasone provoked a rapid externalization of annexin 1 (maximal at 2h) followed by delayed time-dependent changes in the cell cytosol. Saos-2 cell surface expression of FPR or FPRL-1 could not be detected, even when dexam…
Progestogens reduce thromboxane production by cultured human endothelial cells.
2011
Objectives Progestogens have been poorly studied concerning their roles in endothelial physiology. Prostanoids are vasoactive compounds, such as thromboxane A2, a potent vasoconstrictor, and prostacyclin, a vasodilator. We examined the effects of two progestogens used clinically, progesterone and medroxyprogesterone acetate, on thromboxane A2 production by cultured human umbilical vein endothelial cells (HUVEC) and investigated the role of progesterone receptors and the enzymes involved in production of thromboxane A2 and prostacyclin. Methods Cells were exposed to 1‐100 nmol/l of either progesterone or medroxyprogesterone acetate, and thromboxane A2 production was measured in culture mediu…
Platelet Function During Ticlopidine and Eicosapentaenoic Acid Administration in Patients with Coronary Heart Disease
2010
Antiplatelet drugs have been reported to be useful in unstable angina. This study was designed to investigate the effects of simultaneous administration of ticlopidine and eicosapentaenoic acid (EPA) on platelet function in coronary heart disease (CHD) patients. Ticlopidine significantly reduced platelet aggregation induced by ADP and collagen with no effect on arachidonate metabolism. The aggregation responses to collagen, ADP and arachidonate were not altered significantly by EPA (as fish oil) intake whereas thromboxane A(2) formation was reduced, but not completely inhibited. Combined therapy seems to achieve a more marked degree of inhibition of aggregation together with a fall in the u…
Myocardial blood flow and adenosine A2Areceptor density in endurance athletes and untrained men
2008
Previous human studies have shown divergent results concerning the effects of exercise training on myocardial blood flow (MBF) at rest or during adenosine-induced hyperaemia in humans. We studied whether these responses are related to alterations in adenosine A2A receptor (A2AR) density in the left-ventricular (LV) myocardium, size and work output of the athlete's heart, or to fitness level. MBF at baseline and during intravenous adenosine infusion, and A2AR density at baseline were measured using positron emission tomography, and by a novel A2AR tracer in 10 healthy male endurance athletes (ET) and 10 healthy untrained (UT) men. Structural LV parameters were measured with echocardiography.…
Comparative study of post-natal retinal vascular development in mice models of iPLA2 inhibition and plasmalogen deficiency
2012
Purpose: Plasmalogens are particular phospholipids characterized by the presence of a vinyl-ether bond and of a polyunsaturated fatty acid (PUFA) at sn-1 and sn-2 positions of glycerol, respectively. Even if the plasmalogen content of organs and tissues is well documented, their biological functions are still enigmatic. Plasmalogen deficiency in DAPAT-/- mice leads to developmental abnormalities in retinal vasculature (Acar et al, ARVO 2007 E-Abstract 2978) and to persistent hyaloïd arteries. We hypothesize that plasmalogens regulate retinal vascular development through the liberation of PUFA by a plasmalogen-specific calcium-independent phospholipase A2 (iPLA2). We have performed a compara…
Inhibition of the NF-κB Signaling Pathway Mediates the Anti-inflammatory Effects of Petrosaspongiolide M
2003
Petrosaspongiolide M (PT) is a potent secretory phospholipase A(2) inhibitor and anti-inflammatory agent. This marine metabolite reduced the production of nitrite, prostaglandin E(2), and tumor necrosis factor-alpha in the mouse air pouch injected with zymosan. These effects were also observed in mouse peritoneal macrophages stimulated with zymosan. Inhibition of these inflammatory mediators was related to reductions in inducible nitric oxide synthase, cyclo-oxygenase-2, and tumor necrosis factor-alpha expression. Since nuclear factor-kappaB (NF-kappaB) appears to play a central role in the transcriptional regulation of these proteins by macrophages, we investigated the effects of PT on thi…
One minute papers: rendiment i satisfacció de l'alumnat
2014
El procés de millora d'ensenyament- aprenentatge en el context universitari ha generat l'aplicació de noves o millorades tècniques docents, les quals fomenten una participació activa de l'alumne i una major interacció amb el professor. L'objectiu d'aquest treball ha estat analitzar el grau de satisfacció de l'alumnat universitari amb una de les innovacions docents més populars, sobretot, pel seu baix cost i senzillesa, que és el one minute paper, la qual va registrar una alta taxa de participació en el context analitzat. En particular, aquesta experiència docent es va fer en una assignatura de comptabilitat en el Grau d'Administració i Direcció d'Empreses de la Universitat de Santiago de Co…
Inhibition of Rho modulates cytokine-induced prostaglandin E2 formation in renal mesangial cells.
2003
Stimulation of rat mesangial cells for 24 h with interleukin-1β(IL-1β) plus forskolin (Fk) leads to a marked increase in prostaglandin E 2 (PGE 2 ) synthesis. This effect is further enhanced by the small G-protein Rho inhibitor toxin A. A similar increase in PGE 2 formation is obtained with Y27632, a Rho-dependent kinase inhibitor, and with lovastatin, a hydroxymethylglutaryl-coenzyme A inhibitor which depletes cells from geranylgeranyl moieties and thus blocks Rho activation. In parallel to the increased PGE 2 synthesis, a potentiation of IL-1β-induced secretory group IIA phospholipases A 2 (sPLA 2 -IIA) protein expression also occurs by Rho inhibition. However, only toxin A triggers an in…