Vascular physiology and pathology of circulating xanthine oxidoreductase: from nucleotide sequence to functional enzyme

Abstract

The evolutionarily conserved, cofactor-dependent, enzyme xanthine oxidoreductase exists in both cell-associated and circulatory forms. The exact role of the circulating form is not known; however, several putative physiological and pathological functions have been suggested that range from purine catabolism to a mediator of acute respiratory distress syndrome. Regulation of gene expression, cofactor synthesis and insertion, post-translational conversion, entry into the circulation, and putative physiological and pathological roles for human circulating xanthine oxidoreductase are discussed.

Keywords:

• XANTHINE OXIDOREDUCTASE
• XANTHINE OXIDASE
• XANTHINE DEHYDROGENASE
• TRANSCRIPTIONAL CONTROL
• COFACTOR SYNTHESIS
• REACTIVE OXYGEN AND NITROGEN SPECIES
• ANTIMICROBIAL
• ACUTE RESPIRATORY DISTRESS SYNDROME