Search results for "STIMULATION"
showing 10 items of 2192 documents
New insight into the inhibition of the inflammatory response to experimental delayed-type hypersensitivity reactions in mice by scropolioside A.
2006
Scropolioside A, an iridoid isolated from Scrophularia auriculata ssp. pseudoauriculata, showed anti-inflammatory properties against different experimental models of delayed-type hypersensitivity. This iridoid reduced the oedema induced by oxazolone by 79% (72 h) at 0.5 mg/ear while reducing that induced by sheep red blood cells by 47% (18 h), 45% (24 h) and 36% (48 h) at 10 mg/kg. In vivo it reduced both oedema formation and cell infiltration whereas in vitro it reduced the proliferation of activated T-lymphocytes (IC50 of 67.74 microM). Treatment with scropolioside A (100 microM) 18 and 24 h after phytohemagglutinin stimulation increased the number of cells arrested in the subG(0) phase w…
Interaction of dicaffeoylquinic derivatives with peroxynitrite and other reactive nitrogen species.
2008
Plant phenolic antioxidants, among them catechins and hydroxycinnamoyl conjugates, constitute a well defined class of inhibitors of reactive nitrogen species (RNS). To gain deeper insight in this field, we examined the effects of 3,5-di-O-caffeoylquinic acid (DCA), its methyl ester (DCE) and epigallocatechin gallate (EGCG) in nitrative and oxidative processes. These compounds were found to be strong inhibitors of the nitration of tyrosine residues induced by ONOO- in bovine seroalbumin, with their IC50 values (10-40 microM) notably decreasing in the presence of bicarbonate. When studied on the intracellular protein tyrosine nitration induced by ONOO- in cultured murine fibroblasts as well a…
Nanoscale distribution of TLR4 on primary human macrophages stimulated with LPS and ATI
2019
Toll-like receptor 4 (TLR4) plays a crucial role in the recognition of invading pathogens. Upon activation by lipopolysaccharides (LPS), TLR4 is recruited into specific membrane domains and dimerizes. In addition to LPS, TLR4 can be stimulated by wheat amylase-trypsin inhibitors (ATI). ATI are proteins associated with gluten containing grains, whose ingestion promotes intestinal and extraintestinal inflammation. However, the effect of ATI vs. LPS on the membrane distribution of TLR4 at the nanoscale has not been analyzed. In this study, we investigated the effect of LPS and ATI stimulation on the membrane distribution of TLR4 in primary human macrophages using single molecule localization m…
Identification and characterization of a novel Ets-2-related nuclear complex implicated in the activation of the human interleukin-12 p40 gene promot…
1997
Interleukin-12 (IL-12) is a proinflammatory cytokine produced by antigen-presenting cells in response to many microbial infections. IL-12 plays an important role in the generation of T helper type-1 cells, which favor cell-mediated immune response. IL-12 is composed of two different subunits, p40 and p35, whose expression can be regulated concomitantly or differentially. Monocytic cells, the major producers of IL-12, can be primed by interferon-gamma (IFN-gamma) to produce optimal amounts of IL-12 in response to LPS stimulation as a consequence of bacterial infection. The priming effect is exerted primarily at the transcriptional level on the p40 promoter in conjunction with the effects of …
Application of X-ray microanalysis to study of the expression of endothelial adhesion molecules on human umbilical vein endothelial cells in vitro
1994
A semi-quantitative procedure is described, which allows the evaluation of expression levels of endothelial adhesion molecules on cultured human umbilical vein endothelial cells (HUVEC) using energy dispersive X-ray microanalysis (EDX). As a model two adhesion molecules, E-selection (CD62E; ELAM-1/endothelial leukocyte adhesion molecule-1) and ICAM-1 (intercellular adhesion molecule-1; CD54), were localized by the use of the silver-enhancement colloidal gold method after stimulation of HUVEC with endotoxin lipopolysaccharide (LPS), tumour necrosis factor (TNF) or a phorbol ester (PMA). The analysis was performed in a scanning electron microscope (SEM) at an accelerating voltage of 15 kV wit…
Characterization of two alternative Interleukin(IL)-10 5′UTR mRNA sequences, induced by lipopolysaccharide (LPS) stimulation of peripheral blood mono…
2009
Abstract IL-10 production shows a broad-spectrum of individual response, suggesting a genetic component of approximately 75%. Different polymorphisms located close to, or within the IL-10 gene has been demonstrated to influence its transcription rate whereas the post-transcriptional regulation of IL-10 production has not well elucidated. The main responsible elements at this control level are both the 5′- and 3′-untranslated regions (UTR's) of mRNAs, and as the 3′-UTR regions are mainly involved in the stability and decay rate of mRNAs, the 5′-UTR regions mediate the binding rate of the molecule with ribosomal 40S subunit as a cis-acting element. Herein are report data on the identification…
Role of sinusoidal endothelial cells of the liver in concanavalin A-induced hepatic injury in mice
1996
CD4+ T lymphocytes have been identified as being responsible for organ damage in the murine model of experimental liver injury induced by intravenous injection of concanavalin A (Con A). Liver sinusoidal endothelial cells (SEC) and Kupffer's cells (KC) are among the first cells that come into contact with lymphocytes in the liver sinusoid. We aimed to investigate the respective role of these cell populations in the initial steps of T-cell-mediated liver injury in Con A-induced hepatitis. By electron microscopy, we could show that intravenously applied Con A bound predominantly to SEC but not to KC. KC depletion by gadolinium chloride treatment of mice did not result in protection from liver…
Is There a Future for Non-invasive Brain Stimulation as a Therapeutic Tool?
2019
Several techniques and protocols of non-invasive transcranial brain stimulation (NIBS), including transcranial magnetic and electrical stimuli, have been developed in the past decades. These techniques can induce long lasting changes in cortical excitability by promoting synaptic plasticity and thus may represent a therapeutic option in neuropsychiatric disorders. On the other hand, despite these techniques have become popular, the fragility and variability of the after effects are the major challenges that non-invasive transcranial brain stimulation currentlyfaces. Several factors may account for such a variability such as biological variations, measurement reproducibility, and the neurona…
The expression mechanism of the residual LTP in the CA1 region of BDNF k.o. mice is insensitive to NO synthase inhibition
2011
Abstract BDNF and nitric oxide signaling both contribute to long-term potentiation (LTP) at glutamatergic synapses, but to date, few studies analyzed the interaction of both signaling cascades in the same synaptic pathway. Here we addressed the question whether the residual LTP in the CA1 region of hippocampal slices from heterozygous BDNF knockout mice (BDNF +/− ) is dependent on nitric oxide (NO) signaling. Extracellular recording of synaptic field potentials elicited by presynaptic Schaffer collateral stimulation was performed in the CA1 region of hippocampal slices of 4- to 6-week-old mice, and LTP was induced by a theta burst stimulation protocol. Application of the nitric oxide inhibi…
O2Transport in Skeletal Muscle: Development of Concepts and Current State
1994
When comparing oxygen consumption rates(V O2) of various organs — as shown in Fig. 1 —skeletal muscle is exceptional in two respects: Its consumption rate attains the second largest absolute value of all organs and may vary between rest (0.2 mlO 2.100g-1’• min -1 ) and maximum performance (16 m1O 2.100g-1 • min -1 for electrical stimulation) by a factor of 80, thus covering a range that is by far larger than in any other tissue. In order to understand muscle O 2 transport one has to identify transport mechanisms and evaluate their importance towards bringing about the observed high O 2 fluxes and allowing for their enormous variability.