Search results for "pero"
showing 10 items of 3365 documents
Carbon monoxide: mechanisms of action and potential clinical implications.
2013
International audience; Small amounts of carbon monoxide (CO) are continuously produced in mammals. The intracellular levels of CO can increase under stressful conditions following the induction of HO-1 (heme oxygnase-1), a ubiquitous enzyme responsible for the catabolism of heme. Unlike nitric oxide, which is a free radical, CO does not contain free electrons but may be involved in oxidative stress. The carbonate radical has been proposed to be a key mediator of oxidative damage resulting from peroxynitrite production, likewise, the precursor of the carbonate radical anion being bicarbonate and carbon dioxide. We report herein some of the transcription factors and protein kinases involved …
The proteome and transcriptome analysis ofBacillus subtilis in response to salicylic acid
2007
Phenolic acids that are present in plant-soil ecosystems can be considered as toxins which induce specific stress responses in microorganisms. In this paper, we have analyzed the global response of the soil bacterium Bacillus subtilis to salicylic acid using proteomics and transcriptomics. The results demonstrate that salicylic acid caused predominantly the induction of the SigmaB-dependent general stress response in B. subtilis which is not related to the acidic conditions. Treatment of B. subtilis with growth-inhibitory concentrations of 4 mM salicylic acid caused protein damage in B. subtilis as reflected by the induction of the CtsR and Spx regulons. Both phenolic acid decarboxylases (p…
Phenolic Acid-Mediated Regulation of the padC Gene, Encoding the Phenolic Acid Decarboxylase of Bacillus subtilis
2008
ABSTRACT In Bacillus subtilis , several phenolic acids specifically induce expression of padC , encoding a phenolic acid decarboxylase that converts these antimicrobial compounds into vinyl derivatives. padC forms an operon with a putative coding sequence of unknown function, yveFG , and this coding sequence does not appear to be involved in the phenolic acid stress response (PASR). To identify putative regulators involved in the PASR, random transposon mutagenesis, combined with two different screens, was performed. PadR, a negative transcriptional regulator of padC expression, was identified. padR is not located in the vicinity of padC , and the expression of padR is low and appears const…
Human HepG2 and rat Fao hepatic-derived cell lines show different responses to ciprofibrate, a peroxisome proliferator: analysis by flow cytometry.
1996
Abstract Peroxisome proliferators, and especially hypolipidemic drugs such as ciprofibrate, are known to be hepatocarcinogens in rodents, but their effect in humans is controversial. In an attempt to investigate the effects of ciprofibrate at a cellular level, the analysis of individual whole cells was performed by flow cytometry on samples from two hepatic-derived cell lines: the rat Fao cell line and the human HepG2 cell line. The increase of light scatter signals in rat Fao cells treated for 3 days with ciprofibrate at 250 μMwas related to modifications of intrinsic cellular parameters, such as size and cytoplasmic granularity. Conversely, no variations appeared in human HepG2-treated ce…
Stimulation of peroxisomal palmitoyl-CoA oxidase activity by ciprofibrate in hepatic cell lines: comparative studies in Fao, MH1C1 and HepG2 cells.
1993
The response of two rat cell lines, Fao and MH1C1, and one human cell line, HepG2, to the peroxisome proliferator ciprofibrate, was studied. Using a fluorometric assay for palmitoyl-CoA oxidase, the dose- and time-dependent increase of this enzymatic activity was determined. From the lowest concentration (100 microM) stimulation is evident in the two rat cell lines. In the Fao line, the activity was stimulated reaching a seven-fold increase over the control level at 250 microM after 72 h of treatment. In the MH1C1 line, the maximum stimulation, four- to five-fold, was obtained at 250 and 500 microM after 72 h. In the HepG2 cell line, activity increased two-fold at 250 microM after 72 h reac…
Induction of apoptosis and inhibition of cell growth in human hepatocellular carcinoma cells by COX-2 inhibitors
2005
The aim of the present study was to examine the effects of nonselective (indomethacin) and selective cyclooxygenase-2 (COX-2) inhibitors (NS-398, nimesulide, and CAY10404) on cell growth, cell cycle distribution, and apoptosis in three human hepatocellular carcinoma cell lines (HepG2, HuH-6, and HA22T/VGH) with different characteristics of differentiation and biological behavior. The four COX inhibitors showed a dose-dependent growth-inhibitory effect in all the cell lines. No substantial arrests in the progression of the cells through the cell cycle were observed after treatment of HuH-6 or HA22T/VGH for 48 h with the various inhibitors. On the other hand, there were significant increases …
A novel cell model to study the function of the adrenoleukodystrophy-related protein
2006
X-linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disorder due to mutations in the ABCD1 (ALD) gene. ALDRP, the closest homolog of ALDP, has been shown to have partial functional redundancy with ALDP and, when overexpressed, can compensate for the loss-of-function of ALDP. In order to characterize the function of ALDRP and to understand the phenomenon of gene redundancy, we have developed a novel system that allows the controlled expression of the ALDRP-EGFP fusion protein (normal or non-functional mutated ALDRP) using the Tet-On system in H4IIEC3 rat hepatoma cells. The generated stable cell lines express negligible levels of endogenous ALDRP and doxycycline dosage-dependent lev…
Mechanisms of Increased Vascular Superoxide Production in an Experimental Model of Idiopathic Dilated Cardiomyopathy
2005
Objective— In the present study, we sought to identify mechanisms underlying increased oxidative stress in vascular tissue in an experimental animal model of chronic congestive heart failure (CHF). Methods and Results— Superoxide and nitric oxide (NO) was measured in vessels from cardiomyopathic hamsters (CHF hamsters) and golden Syrian hamsters. We also determined expression of endothelial nitric oxide synthase (NOSIII), the soluble guanylyl cyclase, the cGMP-dependent kinase, and the NADPH oxidase. To analyze the contribution of the renin-angiotensin system to oxidative stress, CHF hamsters were treated with the angiotensin-converting enzyme inhibitor captopril for 200 days (120 mg · kg …
MakingCarexmonophyletic (Cyperaceae, tribe Cariceae): a new broader circumscription
2015
We are grateful to the John D. and Catherine T. MacArthur Foundation for funding of the Biodiversity Synthesis Group of the Encyclopedia of Life (EOL) project, which funded our BioSynC Synthesis meeting at the Field Museum in Chicago in September 2011, when the Global Carex Group was formed. We also thank the US National Science Foundation (NSF) for funding our continuing international collaborative work on the phylogeny and classification of Carex under grants DEB 1255901 to ALH and MJW, and DEB 1256033 to EHR. We also acknowledge with thanks funding for nomenclatural research and for attendance at our second meeting during the Monocots V conference in New York in July, 2013, from the Natu…
Biochemical hepatic alterations and body lipid composition in the herbivorous grass carp (Ctenopharyngodon idella) fed high-fat diets.
2006
High-fat diets may have favourable effects on growth of some carnivorous fish because of the protein-sparing effect of lipids, but high-fat diets also exert some negative impacts on flesh quality. The goal of the study was therefore to determine the effects of fat-enriched diets in juvenile grass carp (Ctenopharyngodon idella) as a typical herbivorous fish on growth and possible lipid metabolism alterations. Three isonitrogenous diets containing 2, 6 or 10% of a mixture of lard, maize oil and fish oil (1:1:1, by weight) were applied to fish for 8 weeks in a recirculation system. Data show that feeding diets with increasing lipid levels resulted in lowered feed intake, decreased growth and f…