Anti-hyperuricemic triterpene saponins from the roots of <i>Achyranthes bidentata</i>

Three new triterpene saponins (<b>1-3</b>) were obtained from <i>Achyranthes bidentata</i>, which were further assayed for the anti-hyperuricemic activities. Their structures were determined through HRESI-MS, NMR data and chemical method. As for the anti-hyperuricemic evaluation, <b>1-3</b> were evaluated against the adenosine/xanthine oxidase induced HK-2 cell model. Compound <b>1</b> showed the most effective activity at 50.0 μM, <b>2</b> and <b>3</b> showed moderate anti-hyperuricemic activities at 50.0 μM and 12.5 μM, respectively, with <b>1</b> and <b>2</b> concentration-dependent, while <b>3</b> on the contrary. Western blot analysis was carried out to investigate the mechanism of <b>1</b>, demonstrating that <b>1</b> reduced uric acid levels partly by regulating the renal urate transporters (OAT1, URAT1 and GLUT9).