12/15-lipoxygenases and phospholipid hydroperoxide glutathione peroxidases are opposite enzymes balancing the intracellular concentration of hydroperoxy lipids. We studied the regulation of both enzymes by interleukins 4 and 13 and found an inverse response. When human lung carcinoma cells A549 were cultured in vitro in the presence of these cytokines, an up-regulation of the 12/15-lipoxygenase...

Horseradish peroxidase has been shown to catalyze the oxidation of veratryl alcohol (3,4-dimethoxybenzyl alcohol) and benzyl alcohol to the respective aldehydes in the presence of reduced glutathione, MnC12, and an organic acid metal chelator such as lactate. The oxidation is most likely the result of hydrogen abstraction from the benzylic carbon of the substrate alcohol leading to eventual dis...

Age-associated changes in several antioxidative factors were studied in blood and liver from mice prone to accelerated senescence aged O.7 to 1.4 years and mice resistant to acce]erated senescence aged 1.0 to 2.1 years. In both strains, actiyities of hepatic glutathione peroxidase (GSH-Px) and glutathione-Stransferase (GST) decrefised significantly with age, and the actiyity of superoxide dismu...

Ruptured pea (Pisum sativum cv. Massey Gem) chloroplasts exhibited ascorbate peroxidase activity as determined by H(2)O(2)-dependent oxidation of ascorbate and ascorbate-dependent reduction of H(2)O(2). The ratio of ascorbate peroxidase to NADP-glyceraldehyde 3-phosphate dehydrogenase activity was constant during repeated washing of isolated chloroplasts. This indicates that the ascorbate perox...