Search results for "Active oxygen"
showing 10 items of 884 documents
Antioxidant compound supplementation prevents oxidative damage in a Drosophila model of Parkinson's disease
2013
Loss-of-function mutations in the DJ-1 gene are linked to rare autosomal recessive forms of parkinsonism. In Drosophila, two DJ-1 orthologs have been identified, DJ-1α and DJ-1β. Several studies have shown that DJ-1β mutant flies are viable and fertile but exhibit age-dependent locomotor defects, shortened life span, and enhanced sensitivity to toxins that induce oxidative stress response compared to control flies. We also demonstrated that long-term dietary supplementation with antioxidant compounds was effective at increasing life-span values of DJ-1β mutants. These results, together with high levels of oxidative stress markers detected in newly eclosed DJ-1β mutant flies compared to cont…
Contact probe voltammetry for in situ monitoring of the reactivity of phenolic tomato (Solanum lycopersicum L.) compounds with ROS
2015
The application of an in situ electrochemical contact probe methodology for monitoring reactivity of antioxidant polyphenolic compounds in tomato fruits is described. Upon electrochemical generation of reactive oxygen species (ROS), characteristic voltammetric responses were recorded for compounds resulting from the reaction of such species with tomato compounds. This suggests that new electrochemically oxidizable compounds are generated from the oxidation of highly reactive polyphenolic compounds with ROS. Therefore, an evaluation of the antioxidant capacity of such species could be made from voltammetric data for different tomato varieties.
Antioxidant and Antiinflammatory Properties of Heme Oxygenase-1 in Osteoarthritic Articular Cells
2012
Heme oxygenase-1 (HO-1) is induced in cells by various stimuli as a defense system against oxidative stress. It is known that reactive oxygen species (ROS) participates in the initiation and progression of osteoarthritis (OA) and several antioxidant systems may protect cartilage components. HO-1 induction or CO release from CORM-2 counteracts oxidative stress and protects against proinflammatory and catabolic effects of interleukin-1β in OA chondrocytes, osteoblasts, and synoviocytes as well as in OA osteochondral explants. Both approaches have been able to downregulate the production of mediators such as reactive oxygen species, nitric oxide, matrix metalloproteinases, prostaglandin E2, cy…
Neuroprotective and Mitoprotective Effects of Lemon IntegroPectin on SH-SY5Y Cells
2021
AbstractLemon IntegroPectin obtained via hydrodynamic cavitation of organic lemon processing waste in water shows significant neuroprotective activity in vitro, as first reported in this study investigating the effects of both lemon IntegroPectin and commercial citrus pectin on cell viability, cell morphology, reactive oxygen species (ROS) production and mitochondria perturbation induced by treatment of neuronal SH-SY5Y human cells with H2O2. Mediated by ROS including H2O2 and its derivatives, oxidative stress alters numerous cellular processes, including mitochondrial regulation and cell signaling, propagating cellular injury that leads to incurable neurodegenerative diseases. These result…
Regulation and Role of Neuroglobin and Cytoglobin Under Hypoxia
2007
Neuroglobin (Ngb) and cytoglobin (Cygb) are two novel members of the globin superfamily that are ubiquitously present in vertebrates. Their exact physiological roles are still uncertain. Here we review the expression of Ngb and Cygb, with particular emphasis on their regulation and potential role under hypoxia. Ngb expression is confined to neurons and some endocrine tissues. At the subcellular level, Ngb is associated with the presence of mitochondria and thus linked to the oxidative metabolism. Hypoxia or ischemic insults most likely do not strongly increase Ngb levels in the rodent brain. This might be explained by the fact that most mammals are not adapted to low oxygen levels. In zebra…
A new ceramide from the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl.
2020
A new ceramide is being reported herein together with six known compounds from the methanol extract of the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl. The metabolites were obtained through repeated open column chromatography and were characterized by spectroscopic and spectrometric techniques. The radical-scavenging activity of the crude extract and isolated compounds was evaluated using the DPPH radical. The obtained results suggest the studied species as prominent candidate to fight reactive oxygen species (ROS).
Electrochemical monitoring of ROS generation by anticancer agents: the case of chartreusin
2017
Solution phase and solid-sate electrochemical techniques centered in the voltammetry of microparticles approach are applied for testing the cytotoxic activity of anticancer drugs. The possibility of electrochemical generation of reactive oxygen species (ROS) is exploited for evaluating their contribution to cellular damage. The described methodology is applied to the case of chartreusin (Ch) whose electrochemistry in non-aqueous solutions and in the solid state in contact with aqueous electrolytes is described in the absence (experimental data were confirmed by theoretical calculations) and in the presence of double-stranded DNA (dsDNA). In parallel, scanning electrochemical microscopy (SEC…
The Role of Mitochondrial Reactive Oxygen Species Formation for Age-Induced Vascular Dysfunction
2010
Aging is an important risk factor for the development of cardiovascular diseases, which can be accelerated by atherosclerosis, diabetes, hypercholesterolemia, or obesity. Vascular aging is mainly characterized by endothelial dysfunction, an alteration of endothelium-dependent signaling processes, and vascular remodeling. The underlying mechanisms include increased production of reactive oxygen species (ROS), inactivation of nitric oxide (•NO), and subsequent formation of reactive nitrogen and oxygen species (RNOS). Elevated RNOS may exhibit new messenger functions by posttranslational oxidative modification of intracellular regulatory proteins or lead to irreversible alterations of biologic…
Beeinflussung des Leberzellmetabolismus, der Freisetzung von reaktiven Sauerstoffspezies sowie Apoptoseaktivierung durch hypotherme oxygenierte Leber…
2003
Two different methods of liver preservation were compared : simple cold storage (CS) and hypothermic oxygenated perfusion extracorporal (HOPE). After 10 h of preservation (4°C) with modified UW solution reperfusion was performed by isolated liver perfusion for 90 minutes. Reperfusion injury was estimated by release of cytosolic enzymes, formation of superoxide anions, determination of lipid peroxidation, glycolytic metabolites, bileflow and by PCR analysis. The results showed that after cold storage the formation of reactive oxygen species was significant higher as compared with perfused livers. Correspondingly expressions of mediators (TNFα, NF kappa B, MIP-2, SAPK) and apoptosis (Caspase …
Reactive oxygen species mediate angiotensin II-induced leukocyte-endothelial cell interactions in vivo
2001
Abstract Chronically elevated angiotensin II (Ang-II)-induced hypertension is partly mediated by superoxide production. In this study, we have investigated whether the leukocyte-endothelial cell interactions elicited by Ang-II involve reactive oxygen species (ROS) generation. Intravital microscopy within the rat mesenteric microvessels was used. Superfusion (60 min) with Ang-II (1 nM) induced significant increases in leukocyte rolling flux, adhesion, and emigration, which were inhibited by pretreatment with superoxide dismutase or catalase. Dihydrorhodamine-123 oxidation indicated that ROS are primarily produced by the vessel wall. Administration of dimethylthiourea, desferrioxamine, or N-a…