We previously showed that hydrogen peroxide (H2O2) induced resistance artery relaxation independent of endothelium. Thus, in this study we investigated the mechanism of relaxation induced by H2O2 on human renal vascular smooth muscle cell (HVSMC). HVSMC were stimulated with H2O2 and/or angiotensin II (Ang II), proline-rich-tyrosine-kinase-2 (PYK2), ERK1/2 MAP-Kinase, and myosin light chain 20 p...

Reactive oxygen species produce oxidized bases, deoxyribose lesions and DNA strand breaks in mammalian cells. Previously, we demonstrated that aldehydic DNA lesions (ADLs) were induced in mammalian cells by 10 mM hydrogen peroxide (H2O2). Interestingly, a bimodal H2O2 dose-response relationship in cell toxicity has been reported for Escherichia coli deficient in DNA repair as well as Chinese ha...

BACKGROUND Reactive oxygen species play critical roles in homeostasis and cell signaling. Dexmedetomidine, a specific agonist of the α2-adrenoceptor, has been commonly used for sedation, and it has been reported to have a protective effect against oxidative stress. In this study, we investigated whether dexmedetomidine has a protective effect against H2O2-induced oxidative stress and the mechan...

bis-(l-tyrosinato)copper(ii) was reacted with 3-(chloropropyl)-trimethoxysilane functionalized silica that has infused magnetite to yield a magnetically separable catalyst in which the copper carboxylate is covalently linked to the silica matrix through the silane linkage. the immobilized catalyst has been characterized by spectroscopic studies (such as ft-ir, epr, magnetic measurement, sem) an...

This paper reports on the response of a fiber-optic sensing probe to small concentrations of hydrogen peroxide (H2O2) vapor at room temperature. H2O2 has extensive applications in industrial and medical environments. Conversely, H2O2 can be a health hazard by itself. For example, H2O2 induces cellular damage in human cells and its presence can be used to diagnose illnesses such as asthma and hu...

The vasoactive effects of oxidative stress induced by hydrogen peroxide (H2O2) on human umbilical artery strips as well as the possible mechanisms involved are studied. Contraction responses to cumulative H2O2 (10 M 3 × 10 M) in endothelium intact and denuded umbilical arteries and responses to cumulative H2O2 after incubation with L-NAME (10 M) (n = 8), indomethacin (10 M) (n = 8) and verapami...

Ascorbic acid (AA) has antioxidant properties. However, in the presence of Fe2+/Fe3+ ions and H2O2, it may behave as a pro-oxidant by accelerating enhancing formation hydroxyl radicals (•OH). Therefore, this study we evaluated effect AA at concentrations 1 to 200 µmol/L on •OH-induced light emission (at pH 7.4 temperature 37 °C) from 92.6 Fe2+—185.2 EGTA (ethylene glycol-bis (β-aminoethyl ether...

Hydrogen peroxide (H2O2) is a reactive oxygen species (ROS) that plays a dual role in plant cells. Here, we discovered that drought (20% polyethylene glycol-6000, PEG)-triggered decreases of HO-1 transcript expression and HO activity. However, exogenous H2O2 contributed toward the increase in HO-1 gene expression and activity of the enzyme under drought stress. Meanwhile, the HO-1 inducer hemat...