Search results for "Active oxygen"

Effects of a high-fat diet on energy metabolism and ROS production in rat liver.

2011

International audience; BACKGROUND & AIMS: A high-fat diet affects liver metabolism, leading to steatosis, a complex disorder related to insulin resistance and mitochondrial alterations. Steatosis is still poorly understood since diverse effects have been reported, depending on the different experimental models used. METHODS: We hereby report the effects of an 8 week high-fat diet on liver energy metabolism in a rat model, investigated in both isolated mitochondria and hepatocytes. RESULTS: Liver mass was unchanged but lipid content and composition were markedly affected. State-3 mitochondrial oxidative phosphorylation was inhibited, contrasting with unaffected cytochrome content. Oxidative…

Release of copper-amended particles from micronized copper-pressure-treated wood during mechanical abrasion

2016

Background We investigated the particles released due to abrasion of wood surfaces pressure-treated with micronized copper azole (MCA) wood preservative and we gathered preliminary data on its in vitro cytotoxicity for lung cells. The data were compared with particles released after abrasion of untreated, water (0% MCA)-pressure-treated, chromated copper (CC)-pressure-treated wood, and varnished wood. Size, morphology, and composition of the released particles were analyzed. Results Our results indicate that the abrasion of MCA-pressure-treated wood does not cause an additional release of nanoparticles from the unreacted copper (Cu) carbonate nanoparticles from of the MCA formulation. Howev…

Oxidative stress and antioxidants in the pathophysiology of malignant melanoma.

2018

Abstract The high number of somatic mutations in the melanoma genome associated with cumulative ultra violet (UV) exposure has rendered it one of the most difficult of cancers to treat. With new treatment approaches based on targeted and immune therapies, drug resistance has appeared as a consistent problem. Redox biology, including reactive oxygen and nitrogen species (ROS and RNS), plays a central role in all aspects of melanoma pathophysiology, from initiation to progression and to metastatic cells. The involvement of melanin production and UV radiation in ROS/RNS generation has rendered the melanocytic lineage a unique system for studying redox biology. Overall, an elevated oxidative st…

Effects of Long-Term Nitroglycerin Treatment on Endothelial Nitric Oxide Synthase (NOS III) Gene Expression, NOS III–Mediated Superoxide Production, …

2000

Abstract —Long-term nitroglycerin (NTG) treatment has been shown to be associated with cross-tolerance to endothelium-dependent vasodilators. It may involve increased production of reactive oxygen species (such as superoxide, O 2 ·− ) that rapidly inactivate the nitric oxide (NO) released from the endothelial cells. It remains to be elucidated, however, whether long-term treatment with NTG alters the activity and expression of the endothelial NO synthase (NOS III) and whether this enzyme can contribute to O 2 ·− formation. We studied the influence of long-term NTG treatment on the expression of NOS III as assessed by RNase protection assay and Western blot. Tolerance was measured ex vivo i…

Harmful and Beneficial Role of ROS 2017.

2018

Structure and function of the vacuolar Ccc1/VIT1 family of iron transporters and its regulation in fungi

2020

Iron is an essential micronutrient for most living beings since it participates as a redox active cofactor in many biological processes including cellular respiration, lipid biosynthesis, DNA replication and repair, and ribosome biogenesis and recycling. However, when present in excess, iron can participate in Fenton reactions and generate reactive oxygen species that damage cells at the level of proteins, lipids and nucleic acids. Organisms have developed different molecular strategies to protect themselves against the harmful effects of high concentrations of iron. In the case of fungi and plants, detoxification mainly occurs by importing cytosolic iron into the vacuole through the Ccc1/V…

Oxidative stress, glutathione, and gene expression as key indicators in SH-SY5Y cells exposed to zearalenone metabolites and beauvericin.

2020

The co-presence of mycotoxins from fungi of the genus Fusarium is a common fact in raw food and food products, as trace levels of them or their metabolites can be detected, unless safety practices during manufacturing are carried out. Zearalenone (ZEA), its metabolites α-zearalenol (α-ZEL) and β-zearalenol (β-ZEL) and, beauvericin (BEA) are co/present in cereals, fruits or their products which is a mixture that consumer are exposed and never evaluated in neuronal cells. In this study the role of oxidative stress and intracellular defense systems was assessed by evaluating reactive oxygen species (ROS) generation and glutathione (GSH) ratio activity in a human neuroblastoma cell line, SH-SY5…

Pathophysiology of polymorphonuclear leukocyte in arterial hypertension

2009

This review shows how polymorphonuclear leukocytes (PMNs) play a pivotal role in the development of the organ injury that is associated with arterial hypertension. Elevated white blood cell count and higher levels of PMNs activation are risk factors for arterial hypertension and cardiovascular disease. Spontaneously activated PMNs release proinflammatory factors and reactive oxygen species, which have negative effects on vascular tone and on their adhesion to the endothelium. The oxidative stress in hypertensive PMNs is revealed by increased NADPH-oxidase production and lipid peroxidation and by decreased cytosolic and mitochondrial superoxide dismutase concentrations. The overexpression of…

Even free radicals should follow some rules: a guide to free radical research terminology and methodology.

2014

Free radicals and oxidants are now implicated in physiological responses and in several diseases. Given the wide range of expertise of free radical researchers, application of the greater understanding of chemistry has not been uniformly applied to biological studies. We suggest that some widely used methodologies and terminologies hamper progress and need to be addressed. We make the case for abandonment and judicious use of several methods and terms and suggest practical and viable alternatives. These changes are suggested in four areas: use of fluorescent dyes to identify and quantify reactive species, methods for measurement of lipid peroxidation in complex biological systems, claims of…

Exposure to ototoxic agents and hearing loss: A review of current knowledge

2014

Several experimental and clinical studies have shown that a variety of ototoxic agents (such as drugs, industrial chemicals and noise) can cause sensorineural hearing loss. The most common ototoxic drugs used in clinical practice include: aminoglycoside and macrolide antibiotics, quinoline anti-malarials, platinum analog antineoplastics, loop diuretics, and acetylsalicylic acid. Among chemical agents with potential ototoxic properties are: organic solvents, heavy metals, organotins, nitriles, asphyxiants, and pesticides/herbicides. Acoustic exposure to high intensity and/or prolonged noise can also cause permanent threshold shifts in auditory perception. Ototoxic agents can influence audito…