Urtica L. has been long used for
gout in
traditional Tibetan medicine and is closely related to the effect of reducing
uric acid. This study aimed to investigate the effect of Urtica hyperborea Jacq. ex Wedd. (UW) on lowering
uric acid and its mechanism by using HK2 cells and
hyperuricemia mouse model.
Petroleum ether extract (UWP),
ethyl acetate extract (UWE),
n-butanol extract (UWB), and alcohol-soluble extract (UWA) from UW were prepared, and HK2 cells were treated with various parts extracts to observe the expression of
uric acid transporter at 25, 50, and 100 μg/mL for 24 h. Moreover,
hyperuricemia mice were administered orally various parts extracts at 0.78 and 2.34 g/kg (crude
drug dose converted by extraction rate) to observe the change of hepatic XOD, serum ADA, renal function, and
uric acid transporter. In vitro experiments showed that UWA can remarkably elevate OAT1 expression and decrease URAT1 expression in HK2 cells. In vivo experiments showed that UWP, UWE, UWB, and UWA showed remarkable activity in reducing
uric acid, rendering a substantial decline in the SUA level in
hyperuricemia mice. Compared with the
hyperuricemia and
allopurinol groups, UWB and UWA had significant protective effects on renal injury. At the same time, UWA can significantly reduce the activity of XOD and ADA, reduce the expression of URAT1, and increase the expression of OAT1. These results indicated that UWA had an outstanding
uric acid lowering effect and did not affect renal function. This may be related to increased
uric acid excretion and decreased
uric acid production, mediated by renal OAT1, URAT1, liver XOD, and serum ADA. UWA may be a potential
drug against
hyperuricemia.