1. The hypothesis was tested that the renal xanthine oxidase system provides a source of oxygen free radicals in puromycin aminonucleoside and adriamycin experimental nephrosis by generating uric acid from hypoxanthine and xanthine. 2. The concentrations in renal tissue of the putative intermediary products of puromycin aminonucleoside metabolism, hypoxanthine and xanthine, and of their precurs...

The free radical-generating enzyme xanthine oxidase has been hypothesized to be a central mechanism of the injury which occurs in postischemic tissues; however, its importance remains controversial. Much attention has focused on the role of this enzyme in myocardial reperfusion injury. While xanthine oxidase has been observed in ischemic tissue homogenates, the presence and importance of radica...

Rat liver cytosol and buttermilk xanthine oxidase both converted 7-deoxypyrromycinone, the 7-deoxyaglycone of marcellomycin, a new anthracycline antibiotic, to a nonfluorescent compound under anaerobic conditions and in the presence of an electron donor. Reduced nicotinamide adenine dinucleotide and reduced nicotinamide adenine dinucleotide phosphate were equally effective electron donors for l...

In the liver tissue of newborn mice, xanthine oxidase activity is very low during the first 7 to 14 days of life. Infection of mice with several different viruses prematurely induced xanthine oxidase activity 2- to 10-fold in the liver tissue. Generally, overt signs of illness appeared after xanthine oxidase induction; however, some viruses induced the enzyme activity without causing morbidity ...

A new compound (C20H18O9) was isolated from bambara groundnut seeds (Vigna subterranea (L.) Verdc.) and identified as a luteolin glycoside based on 1H, 13C 2D nuclear magnetic resonance spectroscopy data previously reported data. This exhibited similar scavenging activity for DPPH radical to Trolox had higher inhibitory effect superoxide anion radicals than gallic acid Trolox. C20H18O9 an radic...

A patient with complete deficiency of xanthine oxidase would not be expected to oxidase allopurinol to oxipurinol if allopurinol did not have any alternative metabolic pathway. 400 mg of allopurinol was administered to a patient with xanthine oxidase deficiency, and plasma allopurinol, oxipurinol, hypoxanthine, and xanthine levels were determined serially by the use of high-performance liquid c...

The results of the screening of thirty-one species belonging to the lichen family Graphidaceae for their ability to scavenge superoxide and inhibition of tyrosinase and xanthine oxidase activities have been presented. Graphina glaucorufa, Graphina multistriata, Graphina salacinilabiata, Graphis assamensis, Graphis nakanishiana and Phaeographopsis indica showed strong inhibition of tyrosinase an...

Xanthine oxidase (EC 1.2.3.2) activity increases in liver of rabbits deficient in vitamin E. Immunochemical titration of the enzyme demonstrates that the elevation of activity is due to an increased accumulation of the enzyme protein rather than activation of preexisting enzyme molecules. Immunochemically, xanthine oxidase from deficient animals is indistinguishable from the enzyme from control...

The enzyme xanthine oxidase has been implicated as a generator of toxic oxygen metabolites that contribute to ischemic injury. Because substantial species variability has been demonstrated and because there are minimal human data available, the relevance of xanthine oxidase to human heart damage has been in doubt. We report the absence of xanthine oxidase activity in nine human heart biopsy spe...

Xanthine oxidase inhibitory activity has been reported from different plants such as Cinnamomum cassia, Chrysanthemum indicum, Lycopus europaeus, Polygonum cuspidatum, Acacia confuse, Coccinia grandis, Datura metel, Strychnos nux-vomica, Vitex negundo, Coccinia grandis, Vitex negundo, Fraxinus angustifolia, Pistacia lentiscus, Hyptis obtusiflora, H. lantanaefolia, Artemisia vulgaris, Caesalpini...