the protective effects of rheum tanguticum polysaccharide 1 (rtp1), which is extracted from the chinese traditional medicine rheum tanguticum, on radiation-induced intestinal mucosal injury was investigated. rat intestinal crypt epithelial cells (iec-6 cells) and sprague-dawley rats were each divided into control, irradiated and rtp1-pretreated irradiated groups. after irradiation, cell surviva...

Previous studies have shown that the human salivary antifungal peptide histatin 5 is taken up by Candida albicans cells and associates intracellularly with mitochondria. The purpose of the present study was to investigate the biological consequence of this specific subcellular targeting. Histatin 5 inhibited respiration of isolated C. albicans mitochondria as well as the respiration of intact b...

Platelets participate not only in thrombus formation but also in the regulation of vessel tone, the development of atherosclerosis, angiogenesis, and in neointima formation after vessel wall injury. It is not surprising, therefore, that the platelet activation cascade (including receptor-mediated tethering to the endothelium, rolling, firm adhesion, aggregation, and thrombus formation) is tight...

Cytochrome P450s (CYPs) are functionally diverse monooxygenases that receive their reducing equivalents from the cofactor NADPH. The stoichiometry of cofactor consumption and product formation is not always 1:1, and excessive NADPH consumption can lead to reactive oxygen species (ROS) formation. Previous studies have monitored NADPH consumption with capillary electrophoresis as a measure of met...

Histidine-copper(II) complex (Cu-His2) is a form of bound copper necessary for cellular copper uptake. Due to the high affinity of histidine to copper(II) ions, the binding of copper(II) by histidine is considered a substantial part of plasma antioxidative defense. Also cysteine plays a role in the antioxidative system. However, we show here that in the presence of oxygen the histidine-copper(I...

NADPH oxidases (NOXs) represent the only known dedicated source of reactive oxygen species (ROS) and thus a prime therapeutic target. Type 4 NOX is unique as it produces H2O2, is constitutively active, and has been suggested to localize to cardiac mitochondria, thus possibly linking mitochondrial and NOX-derived ROS formation. The aim of this study was to identify NOX4-binding proteins and exam...

PURPOSE Induction of oxidative stress by Organophosphate compounds (OPs) has been previously reported. In the present work, the mechanism of protective effects of N-acetylcysteine as a glutathion (GSH) prodrug against malathion-induced cell toxicity was investigated. In this work, freshly isolated rat hepatocytes were used to determine the effect of NAC on malathion-induced cytotoxicity, format...

Electrophilic lipids, such as 4-hydroxynonenal (HNE), and the cyclopentenones 15-deoxy-Delta12,14 -prostaglandin J2 (15d-PGJ2) and 15-J2-isoprostane induce both reactive oxygen species (ROS) formation and cellular antioxidant defenses, such as heme oxygenase-1 (HO-1) and glutathione (GSH). When we compared the ability of these distinct electrophiles to stimulate GSH and HO-1 production, the cyc...

Activation and deactivation of macrophages are of considerable importance during the development of various disease states, atherosclerosis among others. Macrophage activation is achieved by oxidized lipoproteins (oxLDL) and is determined by oxygen radical (ROS) formation. The oxidative burst was measured by flow cytometry and quantitated by oxidation of the redox-sensitive dye dichlorodihydrof...

The availability of oxygen (O(2)) is a critical parameter affecting vascular tube formation. In this study, we hypothesize that dissolved oxygen (DO) levels in collagen gels change during the three-dimensional (3D) culture of human umbilical vein endothelial cells (HUVECs) in atmospheric conditions and that such changes affect the kinetics of tube formation through the production of reactive ox...