How is xanthine oxidase produced?
Xanthine oxidase (XO) XDH can be converted to XO irreversibly by limited proteolysis or reversibly by thiol oxidation or phosphorylation. Only XO produces ROS, catalyzing the oxidative hydroxylation of purine substrates with the formation of O2·− and H2O2; under hypoxia significantly more H2O2 is formed than O2·−.
Where is xanthine oxidase produced?
Xanthine oxidase is a superoxide-producing enzyme found normally in serum and the lungs, and its activity is increased during influenza A infection.
What does xanthine oxidase inhibitor do?
Inhibition of xanthine oxidase, the enzyme that synthesizes uric acid from hypoxanthine, reduces the synthesis of uric acid without disrupting the biosynthesis of vital purines. This results in the reduction of the tissue stores of uric acid.
What is xanthine oxidase deficiency?
Definition. Xanthine oxidase (xanthine dehydrogenase) deficiency, type I, is an uncommon autosomal recessive disorder characterized by the excretion of urinary xanthine and hypoxanthine as the chief end products of purine metabolism, and by low serum and urinary uric acid levels.
Which of the following is xanthine oxidase inhibitors?
Xanthine oxidase inhibitors are of two kinds: purine analogues and others. Purine analogues include allopurinol, oxypurinol, and tisopurine. Others include febuxostat, topiroxostat, and inositols (phytic acid and myo-inositol).
How is xanthine oxidase deficiency diagnosed?
Xanthine oxidase catalyses the oxidation of hypoxanthine to xanthine and xanthine to uric acid, hence the biochemical abnormalities which define the syndrome. The disorder may be asymptomatic, and diagnosed only after the fortuitous finding of a low serum urate, usually less than 2 mg/dl.
What does the word xanthine mean?
: a feebly basic compound C5H4N4O2 that occurs especially in animal or plant tissue, is derived from guanine and hypoxanthine, and yields uric acid on oxidation also : any of various derivatives of xanthine (such as methylxanthine)