OBJECTIVE Eurycoma longifolia is a tropical medicinal plant belonging to Simaroubaceae distributed in South East Asia.The aim of this study is to explore the effect and mechanism of E.longifolia stem 70%ethanol extrac...OBJECTIVE Eurycoma longifolia is a tropical medicinal plant belonging to Simaroubaceae distributed in South East Asia.The aim of this study is to explore the effect and mechanism of E.longifolia stem 70%ethanol extract(EL)and its active com⁃poundson uric acid excretion.METHODS Potassium oxonate(PO)induced hyperuricemia rats and adenine-PO induced hyperuricemia mouse model were used to evaluate the effects of EL.Ultra Performance Liquid Chromatography was used to determine the levels of plasma or serum uric acid and creatinine.Hematoxylin-eosin staining was applied to observe kidney pathological changes,Western blot⁃ting was applied to detect protein expression levels of uric acid transporters.Effects of constituents on urate uptake were tested in hU⁃RAT1-expressing HEK293T cells.RESULTS EL significantly reduced serum and plasma uric acid levels at dosages of 100,200 and 400 mg·kg^-1 in hyperuricemia rats and mice,and increased the clearance rate of uric acid and creatinine,improved therenal pathological injury.The protein expression levels of urate reabsorption transporter 1(URAT1)and glucose transporter 9 were down-regulated while sodium-dependent phosphate transporter 1 and ATP-binding cassette transporter G2 were up-regulated in the kidney after EL treat⁃ment.The diterpenes(50μmol·L^-1)isolated from EL showed inhibitory effects on urate uptake in hURAT1-expressing HEK293T cells,and the effect of eurycomanol was further confirmed in vivo.CONCLUSION EL significantly reduced blood uric acid levels and prevented pathological changes of kidney in PO induced hyperuricemia animal model,improved renal urate transports.We partly clarified the mechanism was related to suppressing effect of URAT1 by diterpene in EL.This study is the first to demonstrate that EL plays a role in hyperuricemia by promoting renal uric acid excretion.展开更多
文摘OBJECTIVE Eurycoma longifolia is a tropical medicinal plant belonging to Simaroubaceae distributed in South East Asia.The aim of this study is to explore the effect and mechanism of E.longifolia stem 70%ethanol extract(EL)and its active com⁃poundson uric acid excretion.METHODS Potassium oxonate(PO)induced hyperuricemia rats and adenine-PO induced hyperuricemia mouse model were used to evaluate the effects of EL.Ultra Performance Liquid Chromatography was used to determine the levels of plasma or serum uric acid and creatinine.Hematoxylin-eosin staining was applied to observe kidney pathological changes,Western blot⁃ting was applied to detect protein expression levels of uric acid transporters.Effects of constituents on urate uptake were tested in hU⁃RAT1-expressing HEK293T cells.RESULTS EL significantly reduced serum and plasma uric acid levels at dosages of 100,200 and 400 mg·kg^-1 in hyperuricemia rats and mice,and increased the clearance rate of uric acid and creatinine,improved therenal pathological injury.The protein expression levels of urate reabsorption transporter 1(URAT1)and glucose transporter 9 were down-regulated while sodium-dependent phosphate transporter 1 and ATP-binding cassette transporter G2 were up-regulated in the kidney after EL treat⁃ment.The diterpenes(50μmol·L^-1)isolated from EL showed inhibitory effects on urate uptake in hURAT1-expressing HEK293T cells,and the effect of eurycomanol was further confirmed in vivo.CONCLUSION EL significantly reduced blood uric acid levels and prevented pathological changes of kidney in PO induced hyperuricemia animal model,improved renal urate transports.We partly clarified the mechanism was related to suppressing effect of URAT1 by diterpene in EL.This study is the first to demonstrate that EL plays a role in hyperuricemia by promoting renal uric acid excretion.
