Oxygen-derived free radicals and other oxidizing species are thought to be involved in inflammation and ischemic tissue injuries. Recently, oxygen-derived free radicals also have been implicated in tissue injury of the myocardium subjected to ischemia/reperfusion. The purpose of this investigation was to determine if electrolysis of a physiological buffer would serve as a source of free radical...

Oxidation of low density lipoprotein (LDL) by copper ions is not influenced by glucose in a concentration range between 1 and 20 m M . LDL-oxidation by peroxynitrite or the simulta­ neous action of nitrogen monoxide and superoxide, produced by morpholino-sydnonimine (SIN-1) is considerably enhanced by typical hydroxyl-radical scavengers such as formate or mannitol and by glucose. Since both fre...

Oxidation of low density lipoprotein (LDL) by copper ions is not influenced by glucose in a concentration range between 1 and 20 mM. LDL-oxidation by peroxynitrite or the simultaneous action of nitrogen monoxide and superoxide, produced by morpholino-sydnonimine (SIN-1) is considerably enhanced by typical hydroxyl-radical scavengers such as formate or mannitol and by glucose. Since both free ra...

Human granulocytes were capable of oxidizing 2-keto-4 thiomethylbutyric acid to ethylene during phagocytosis or membrane perturbation. The reaction required hydrogen peroxide and superoxide and in addition was inhibited by various hydroxyl radical (OH) scavengers. These observations represent direct evidence for the generation of OH by human granulocytes. Further, inhibition of ethylene generat...

The oxidation of ethanol by a reconstituted system containing NADPH-cytochrome P-450 reductase and cytochrome P-450 from phenobarbital-treated rats was characterized especially with regard to the role of oxygen radicals in the mechanism of ethanol oxidation. Results described in the preceding manuscript demonstrated that a strong oxidizing species with properties similar to that of the hydroxyl...

Myocardial ischemia causes release of chemotactic factors, migration of neutrophils, peroxidation of lipids, and depletion of free radical scavengers. The invading neutrophils may injure the myocardial vasculature and sarcolemma by generating oxygen free radicals. Several agents that affect neutrophils or oxygen radicals were evaluated in a canine model of regional myocardial ischemia and reper...

The major unexplained phenomenon in fibrotic conditions is an increase in replicating fibroblasts. In this report we present evidence that oxygen free radicals can both stimulate and inhibit proliferation of cultured human fibroblasts, and that fibroblasts themselves release superoxide (O2.-) free radicals. Fibroblasts released O2.- in concentrations which stimulated proliferation, a finding co...

ations of cell and organ function. Table 1 lists some of the better established examples in which radical species, such as the superoxide (O ) and hydroxyl (OH) radicals, and oxidants, such as singlet oxygen, hydrogen peroxide (H202), hypochiorous acid (HOCI), and aldehydes, are believed to play a causal role.’ In view of the general chemical reactivity of all these metabolic intermediates, a p...

In the presence of NADPH and CuCl2, patulin induced the cleavage of ColE1 DNA and lambda phage DNA in vitro. The DNA-cleaving activity of patulin was concentration dependent. At the lowest concentration of patulin, ColE1 supercoiled DNA was relaxed and the highest concentration induced linearization of the DNA. This activity was inhibited by superoxide dismutase, catalase and radical scavengers...

The stimulatory effect of ferrous salts on the peroxidation of phospholipids can be enhanced by EDTA when the concentration of Fe2+ in the reaction is greater than that of EDTA. Hydroxyl-radical scavengers do not inhibit peroxidation until the concentrations of Fe2+ and EDTA in the reaction are equal. Lipid peroxidation is then substantially initiated by hydroxyl radicals derived from a Fenton-...