Abstract: Gout is a recurrent inflammatory disease caused by increased metabolism of purines or abnormal uric acid excretion. Xanthine oxidase (XO) is the key enzyme that regulates the generation of uric acid during the metabolism of purines into uric acid. Its function is to convert hypoxanthine into xanthine and into uric acid. By inhibiting the activity of XO, the production of uric acid can be inhibited, thereby relieving hyperuricemia. In recent years, small molecule uric acid-lowering peptides derived from proteins have attracted the attention of researchers because of their low preparation cost, high safety, easy absorption, and high activity, stability and specificity. This paper presents an overview of XO, and summarizes the general steps for the isolation and identification of XO, summarizes recently discovered mixed and single peptide inhibitors of XO with a special reference to the structural commonness of these inhibitors. This review will hopefully provide novel ideas and directions for researchers to discover new XO inhibitory peptides.

Key words: peptide; gout; hyperuricemia; xanthine oxidase; inhibitor