短穗兔耳草提取物对高尿酸血症小鼠黄嘌呤氧化酶和肾脏尿酸转运体的影响研究

Effect of Lagotis brachystachys Maxim extract on xanthine oxidase and renal urate transporters in hyperuricemia mice

目的:探讨短穗兔耳草提取物降尿酸活性及其作用机制。方法:连续灌胃(ig)给予氧嗪酸钾盐7 d诱导小鼠高尿酸血症,每日造模后1 h ig给予短穗兔耳草提取物2.0,4.0和8.0 g·kg-1。分别检测小鼠血清尿酸(UA)水平、肝脏黄嘌呤氧化酶(XOD)活性的变化,同时RT-PCR和Western Blotting法检测肾脏尿酸转运体URAT1,GLUT9和OAT1的mRNA和蛋白表达水平。结果:短穗兔耳草2.0,4.0和8.0 g·kg-1给药组均可显著降低高尿酸血症小鼠血清尿酸水平。短穗兔耳草低、中、高剂量均可在一定程度抑制小鼠肝脏XOD活性,但与模型组比较无显著性差异;同时均可显著降低小鼠肾脏URAT1和GLUT9的表达,高剂量给药组能显著升高小鼠肾脏OAT1的表达。结论:短穗兔耳草具有降尿酸作用,其作用机制主要是通过对肾脏URAT1,GLUT9和OAT1表达的影响增加尿酸的排泄。

Objective： To investigate the effect of Lagotis brachystachys Maxim extract on potassium oxonate-induced hyperuricemia in mice and its mechanism. Methods： Three doses（ 2. 0,4. 0,8. 0 g·kg-1） of L.brachystachys Maxim extract were administrated to hyperuricemia mice induced by potassium oxonate for 7 d. Serum uric acid levels and hepatic xanthine oxidase（ XOD） activities,as well as mRNA and protein expressions of renal urate transpoters（ URAT1,GLUT9 and OAT1） were analyzed by RT-PCR and Western blotting method. Results：L. brachystachys Maxim extract. Low,moderate and high dose groups significantly lowered the serum uric acid levels in a dose-dependent manner but showed no significant inhibition on hepatic XOD activities compare with control group,at the same time significantly reduced the mRNA expressions of URAT1 and GLUT9 in mice,and high dose group significantly increased the mRNA expressions of OAT1 in mice. Conclusion： L. brachystachys Maxim extract could obviously reduce the level of serum uric acid in hyperuricemia mice and the effect is related to its regulation of expressions of renal urate transporters（ URAT1,GLUT9 and OAT1）.