Effects of lobetyolin on xanthine oxidase activity <i>in vitro</i> and <i>in vivo</i>: weak and mixed inhibition

2019-05-29T10:30:56Z (GMT) by In-Soo Yoon Seung-Sik Cho
<p>Lobetyolin (LBT), a general marker compound mainly found in <i>Codonopsis</i> plants including <i>C. pilosula</i>, <i>C. tubulosa</i>, and <i>C. lanceolata</i>, exhibits antitumor, antiviral, anti-inflammatory, mucosal protective, and antioxidant activities. Xanthine oxidase (XO) catalyzes the formation of uric acid from xanthine, a critical metabolic pathway related to hyperuricemia and gout. The aim of this study was to investigate the effect of LBT on XO activity and its mechanism using <i>in vitro</i> enzyme assay system and <i>in vivo</i> potassium oxonate-induced hyperuricemic mice. LBT was found to weakly inhibit XO activity via a mixed type mechanism. Consistently, the impact of 1-week oral LBT treatment on serum XO activity <i>in vivo</i> is limited in hyperuricemic mice. However, oral LBT at 50 mg/kg significantly reduced hepatic XO activity <i>in vivo</i>. To the best of our knowledge, this is the first study to report effects of LBT on XO activity and its inhibition mechanism.</p>