Search results for "OXIDASE"
showing 10 items of 927 documents
Sildenafil inhibits the ROS production by xanthine oxidase
2008
Xanthine oxidase (XO) catalyzes the hydroxylation of a wide variety of substrates, including purines, pirimidines, pterins d aldehydes, to acids1. At relatively high oxygen pressure, it generates reactive oxygen species (ROS) as superoxides and hydroxyl radicals. The XO, detected in endothelial and epithelial cell outer surface, has been involved in ischemia/reperfusion injury1,2. Furthermore, XO-ROS production has been implicated in chronic hearth failure, inflammatory diseases, LDL oxidation, atherosclerosis, hypertension, cancer, aging1. Allopurinol, a hypoxanthine analogue developed as xanthine oxidase inhibitor 30 years ago, and oxypurinol, its oxidation product, have proved to be effe…
Recent Patents on Oxidative Stress-Related Biomarkers in Chronic Heart Failure: The Central Role of Endothelium and Myeloperoxidase
2013
Endothelial cells are key modulators of multiple physiological processes, and their impairment may result in the generation of endothelial dysfunction and ultimately cardiovascular diseases. Under physiologic conditions, reactive oxygen and nitrogen mediators of endothelial cells act to propagate signals driven by different stimuli, by forming molecules with a longer half-life like hydrogen peroxide. Reactive oxygen species (ROS) are constantly produced as a consequence of aerobic metabolism. Under physiologic conditions, their tendency to cause oxidative damage is counterbalanced by the action of antioxidants or oxidant-scavenging enzymes. An imbalance in favour of oxidants leads to oxidat…
Oxidative stress-driven expression of myeloperoxidase in endothelial cells results in accumulation of markers of oxidative and nitrosative stress in …
2009
Endothelial cells (ECs), are able to manage with higher concentrations of ROS as well as reactive nitrogen species, respect to the other cell types. The unbalance between oxidizing species and antioxidant cellular defences has been implicated in the pathogenesis of cardiovascular diseases. While the role of MPO in the oxidative burst is well established, the effects of this enzyme on endothelial biology have only recently come to light. MPO can interact with endothelial –derived NO causing its depletion and favouring its conversion to nitrogen dioxide radical, a compound responsible of protein nitration generating 3-nitrotyrosine. Moreover, MPO is the only enzyme capable to form hypoclorous…
The effect of Betanin parenteral pretreatment on Jejunal and pulmonary tissue histological architecture and inflammatory response after Jejunal ische…
2019
Intestinal ischemic-reperfusion (IR) injury has detrimental effects on both local and distant organs in the body. Betanin is known for its antioxidant properties, and it is found mostly in vegetables. Therefore, the aim of the present study was to test the hypothesis that betanin administration prior intestinal IR, may be beneficial in protecting jejunal mucosa and lung parenchyma against IR damage. Male specific pathogen-free Charles River Wistar rats were used (n = 42). Betanin (50 mg/kg) was administered intraperitoneally 30 min before ischemia of the superior mesenteric artery lasting 1 h, followed by 1, 4 and 24 h of reperfusion. Immunohistochemical as well as histomorphometrical analy…
Downregulation of myogenic microRNAs in sub-chronic but not in sub-acute model of daunorubicin-induced cardiomyopathy
2016
Cardiac muscle-related microRNAs play important roles in cardiac development and disease by translational silencing of mRNAs, the dominant mechanism of microRNA action. To test whether they could be involved in daunorubicin-associated cardiomyopathy (DACM), we determined expression patterns of myomiRs in two distinct models of DACM. We used 10â12 weeks old male Wistar rats. In the sub-acute model, rats were administered with six doses of daunorubicin (DAU-A, 3Â mg/kg, i.p., every 48Â h). Rats were sacrificed two days after the last dose. In the sub-chronic model, anaesthetized rats were administered a single dose of daunorubicin (15Â mg/kg, i.v., DAU-C). Age-matched controls (CON) receive…
Morphological distribution of μ chains and cd15 receptors in colorectal polyp and adenocarcinoma specimens
2013
BACKGROUND: We have recently investigated the localisation of immunoglobulin-producing cells (IPCs) in inflamed intestinal tissue samples from patients with inflammatory bowel disease (IBD), and identified two main patterns of B lymphocyte infiltration: one characterised by the moderate strong stromal localisation of small B1 cell-like IgM+/CD79+/CD20-/CD21-/CD23-/CD5 ± IPCs, and the other by the peri-glandular localisation of IPCs with irregular nuclei that had surface markers specific for a B cell subset (IgM and CD79), but quantitative differences in their λ and κ chains. The same patients were also tested for CD15+ receptors, which were localised on inflammatory cell surfaces or in the …
Environmental Noise and the Cardiovascular System
2018
Abstract Noise has been found associated with annoyance, stress, sleep disturbance, and impaired cognitive performance. Furthermore, epidemiological studies have found that environmental noise is associated with an increased incidence of arterial hypertension, myocardial infarction, heart failure, and stroke. Observational and translational studies indicate that especially nighttime noise increases levels of stress hormones and vascular oxidative stress, which may lead to endothelial dysfunction and arterial hypertension. Novel experimental studies found aircraft noise to be associated with oxidative stress–induced vascular damage, mediated by activation of the NADPH oxidase, uncoupling of …
Congenital hypothyroidism caused by new mutations in the thyroid oxidase 2 (THOX2) gene
2006
Summary Objective Congenital primary hypothyroidism (CH) occurs in one of 4000 births and in 20% of the cases CH is due to a defect in thyroid hormonogenesis. Candidate genes were examined to determine the precise aetiology of suspected dyshormonogenesis in CH. Design The genes that code for thyroid peroxidase (TPO), pendrin (PDS), sodium iodide symporter (NIS) and thyroid oxidase 2 (THOX2) were sequenced directly from genomic DNA. Patients Two girls found to have CH in the neonatal screening programme and suspected of having thyroid dyshormonogenesis were investigated to identify their molecular defect. Results Patient A had a novel heterozygous 1 bp insertion in the THOX2 gene (ins602…
Redox regulation of E3 ubiquitin ligases and their role in skeletal muscle atrophy
2015
Muscle atrophy is linked to reactive oxygen species (ROS) production during hindlimb-unloading due, at least in part, to the activation of xanthine oxidase (XO). The major aim of our study was to determine the mechanism by which ROS cause muscle atrophy and its possible prevention by allopurinol, a well-known inhibitor of XO widely used in clinical practice, and indomethacin, a nonsteroidal anti-inflammatory drug. We studied the activation of p38 MAP Kinase and NF-?B pathways, and the expression of two E3 ubiquitin ligases involved in proteolysis, the Muscle atrophy F-Box (MAFb) and Muscle RING Finger-1 (MuRF-1). Male Wistar rats (3 mold) conditioned by 14 days of hindlimb unloading (n=18),…
Selenium affects biosilica formation in the demosponge Suberites domuncula
2005
Selenium is a trace element found in freshwater and the marine environment. We show that it plays a major role in spicule formation in the demosponge Suberites domuncula. If added to primmorphs, an in vitro sponge cell culture system, it stimulates the formation of siliceous spicules. Using differential display of transcripts, we demonstrate that, after a 72-h exposure of primmorphs to selenium, two genes are up-regulated; one codes for selenoprotein M and the other for a novel spicule-associated protein. The deduced protein sequence of selenoprotein M (14 kDa) shows characteristic features of metazoan selenoproteins. The spicule-associated protein (26 kDa) comprises six characteristic repe…