It is thought that reactive oxygen species (ROS) participate in the inflammation which characterizes asthma, but the evidence supporting this contention is incomplete. F 2 -isoprostanes (F 2 -IsoPs) are arachidonate products formed on membrane phospholipids by the action of ROS and thereby represent a quantitative measure of oxidant stress in vivo. Using a mass spectrometric assay we measured u...

Hypoxic and oxidant stresses can coexist in biological systems, and oxidant stress has been proposed to activate hypoxia pathways through the inactivation of the 'oxygen-sensing' hypoxia-inducible factor (HIF) prolyl and asparaginyl hydroxylases. Here, we show that despite reduced sensitivity to cellular hypoxia, the HIF asparaginyl hydroxylase--known as FIH, factor inhibiting HIF--is strikingl...

Oxidant stress is a ubiquitous stressor with negative impacts on multiple cell types. ASK1 is a central mediator of oxidant injury, but while mechanisms of its inhibition, such as sequestration by 14-3-3 proteins and thioredoxin, have been identified, mechanisms of activation have remained obscure and the signaling pathways regulating this are not clear. Here, we report that phosphorylation of ...

Since "free radical research" started in 1954, understanding the role of oxidants and antioxidants in physiological and pathological conditions has increased continuously. Oxidants are essentially generated by metabolic enzymes, inflammatory cells and mitochondrial electron leakage; they are indispensable for the cellular redox regulation and may, under certain conditions, have a pro-inflammato...

OBJECTIVE Endogenous expression of apolipoprotein E (apoE) has a significant impact on adipocyte lipid metabolism and is markedly suppressed in obesity. Adipose tissue oxidant stress is emerging as an important mediator of adipocyte dysfunction. These studies were undertaken to evaluate the role of oxidant stress for regulation of adipocyte apoE. RESEARCH DESIGN AND METHODS ApoE gene and prot...

BACKGROUND/AIMS Several pathways contribute to mechanisms by which ethanol induces oxidant stress. While some studies support a role for cytochrome P450 2E1 (CYP2E1), others do not. There is a need to develop oral models of significant ethanol-induced liver injury and to evaluate the possible role of CYP2E1 in ethanol actions in such models. METHODS We evaluated chronic ethanol-induced liver ...

Epithelial mucous membranes are repeatedly exposed to oxidants and xenobiotics. CFTR plays a role in glutathione transepithelial flux and in defining the hydration and viscoelasticity of protective mucus. We therefore hypothesized that CFTR expression and function may be modulated by oxidant stress. A sublethal oxidant stress (tert-butylhydroquinone, BHQ) in CFTR-expressing epithelial cells (T8...

Oxidative stress has been suggested to contribute to the pathophysiology of schizophrenia. Increased oxidative stress is the result of either an increased production of free radicals or a depletion of the endogenous antioxidants. However, whether this imbalance of oxidant-antioxidant status in schizophrenia is integral to disease itself or the effect of antipsychotic drugs is not clearly unders...

Stress has been shown to be associated with altered homeostasis that may lead to oxidant-antioxidant imbalance. Non-enzymatic antioxidants are important regulators of reactive oxygen species produced in extra-cellular milieu and represent the first line of defense against them. Extra-cellular non-enzymatic antioxidants may be disturbed by the production of superoxide and nitric oxide and this h...