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
OBJECTIVE To investigate effects of Wudang cherry on urate excretion and renal function and examined whether renal organic ion transporters were involved in potassium oxonateinduced hyperuricemic mice.METHODS The mode...OBJECTIVE To investigate effects of Wudang cherry on urate excretion and renal function and examined whether renal organic ion transporters were involved in potassium oxonateinduced hyperuricemic mice.METHODS The model of hyperuricemic mice was induced by intraperitoneal injection of potassium oxonate(250 mg·kg^(-1))for 7 d.Water extracts of Wudang cherry at 500 mg·kg^(-1)were orally administered to hyperuricemic mice for 7 d,benzbromarone(20 mg·kg^(-1))and allopurinol(20 mg·kg^(-1))were given as positive controls,vehicle control group was given equal normal saline.Serum and urine levels of uric acid were measured in hyperuricemic and normal mice.Simultaneously,the m RNA and protein levels of mouse urate transporter 1(m URAT1),glucose transporter 9(mGLUT9),organic anion transporters(mOAT1 and mOAT3),ATP-binding cassette,subfamily G,membrane 2(mABCG2)and organic cation/carnitine transporters(m OCT1,m OCT2,m OCTN1 and m OCTN2)in the kidney were analyzed by Western blot,RT-PCR,immunohistochemical and immunofluorescent assay,respectively.RESULTS Wudang cherry significantly reduced serum uric acid levels and increased urine uric acid levels in hyperuricemic mice.And it effectively reversed potassium oxonate-induced alterations in renal m URAT1,mGLUT9,mOAT1,mOAT3 and mABCG2 m RNA and protein levels,resulting in the enhancement of renal urate excretion in mice.Moreover,Wudang Cherry increased renal m OCT1,m OCT2,m OCTN1 and m OCTN2 m RNA and protein levels,and improved renal impairment in this model.CONCLUSION Wudang cherry processes uricosuric and nephroprotective actions by regulating renal organic ion transporters in hyperuricemic mice.展开更多
Objective: Persons with type 2 diabetes have increased incidence of hyperuricemia and gout. The hypothesis that Urate transporter 1 (URAT1) levels are increased in type 2 diabetic Zucker rats and this is responsible f...Objective: Persons with type 2 diabetes have increased incidence of hyperuricemia and gout. The hypothesis that Urate transporter 1 (URAT1) levels are increased in type 2 diabetic Zucker rats and this is responsible for elevation of uric acid was tested. Methods: Male 12-week-old obese Zucker rats were compared to non-diabetic lean counterparts. Plasma glucose, uric acid and creatinine were measured. URAT1 protein levels in the renal cortex and medulla were determined by Western blot. Immunohistochemistry was used to determine the location of URAT1 inrenal tubules. Results: Plasma glucose and uric acid levels were higher in the diabetic rats. There was no difference in plasma createnine. URAT1 antibody-positive bands of 27, 31, 50, 62 and 70 kDa were observed in cortex. A similar pattern was observed in medulla with addition of a 44 kDa band. No differences were observed in URAT1 proteins in the cortex between obese and lean rats. In the medulla, expression of the 44 and 50 kDa proteins was higher in lean rats. Expression of 27, 50, 62 kDa URAT1 proteins in the cortex was higher than in the medulla, while expression of the 70 kDa URAT1 was higher in medulla than in cortex. Localization of URAT1 did not differ between groups and included tubules in both cortex and medulla. Conclusions: In male Zucker rats, URAT1 protein expression was observed in both kidney cortex and medulla. Uric acid elevation in the obese group was associated with decreases in the 44 and 50 kDa URAT1 proteins in renal medulla.展开更多
Objective： To explore the effect of Compound Tufuling Granules （复方土茯苓颗粒, CTG） on regulating glucose transporter 9 （GLUT9） expression in the kidney to influence the uric acid excretion by the kidney and ser...Objective： To explore the effect of Compound Tufuling Granules （复方土茯苓颗粒, CTG） on regulating glucose transporter 9 （GLUT9） expression in the kidney to influence the uric acid excretion by the kidney and serum uric acid （SUA） level in hyperuricemia mice. Methods： Sixty Kunming male mice were randomly divided into the control group, model group, benzbromarone group, and CTG high-, middle- and low- dose groups. The yeast extract and uricase inhibition method were used to build hyperuricemia model, and the corresponding drugs were administrated on the 7th day. On the 21st day the 24-h urine was collected, on the 22rid day the blood was collected, the SUA level was detected by uricase colorimetry, and the mRNA and protein expressions of GLUT9 were detected by quantitative real-time polymerase chain reaction and Western blot, respectively. Results： Compared with the model group, the levels of SUA and the mRNA and protein expressions of GLUT9 were significantly decreased, and the fraction excretion of uric acid （FEUA） was significantly increased in the CTG groups and benzbromarone group （all P〈0.05）. There was no significant difference in the above indicators between the CTG high-dose group and benzbromarone group （P〉0.05）. SUA is positively related to the GLUT9 mRNA and protein expressions in the kidney （P〈0.05 or P〈0.01）. Conclusions： CTG can significantly reduce the SUA and increase the FEUA. In addition, CTG can effectively inhibit the mRNA and protein expressions of GLUT9 in the kidney of hyperuricemia mice to inhibit the uric acid re-absorption, promote uric acid excretion and reduce SUA.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.
基金supported by National Natural Science Foundation of China(81402994)Natural Science Foundation of Hubei Province(2014CFB652)"2011 Plan" Open Fund Innovation Team Project of Hubei Province(2011JH-2014CXTT08)
文摘OBJECTIVE To investigate effects of Wudang cherry on urate excretion and renal function and examined whether renal organic ion transporters were involved in potassium oxonateinduced hyperuricemic mice.METHODS The model of hyperuricemic mice was induced by intraperitoneal injection of potassium oxonate(250 mg·kg^(-1))for 7 d.Water extracts of Wudang cherry at 500 mg·kg^(-1)were orally administered to hyperuricemic mice for 7 d,benzbromarone(20 mg·kg^(-1))and allopurinol(20 mg·kg^(-1))were given as positive controls,vehicle control group was given equal normal saline.Serum and urine levels of uric acid were measured in hyperuricemic and normal mice.Simultaneously,the m RNA and protein levels of mouse urate transporter 1(m URAT1),glucose transporter 9(mGLUT9),organic anion transporters(mOAT1 and mOAT3),ATP-binding cassette,subfamily G,membrane 2(mABCG2)and organic cation/carnitine transporters(m OCT1,m OCT2,m OCTN1 and m OCTN2)in the kidney were analyzed by Western blot,RT-PCR,immunohistochemical and immunofluorescent assay,respectively.RESULTS Wudang cherry significantly reduced serum uric acid levels and increased urine uric acid levels in hyperuricemic mice.And it effectively reversed potassium oxonate-induced alterations in renal m URAT1,mGLUT9,mOAT1,mOAT3 and mABCG2 m RNA and protein levels,resulting in the enhancement of renal urate excretion in mice.Moreover,Wudang Cherry increased renal m OCT1,m OCT2,m OCTN1 and m OCTN2 m RNA and protein levels,and improved renal impairment in this model.CONCLUSION Wudang cherry processes uricosuric and nephroprotective actions by regulating renal organic ion transporters in hyperuricemic mice.
文摘Objective: Persons with type 2 diabetes have increased incidence of hyperuricemia and gout. The hypothesis that Urate transporter 1 (URAT1) levels are increased in type 2 diabetic Zucker rats and this is responsible for elevation of uric acid was tested. Methods: Male 12-week-old obese Zucker rats were compared to non-diabetic lean counterparts. Plasma glucose, uric acid and creatinine were measured. URAT1 protein levels in the renal cortex and medulla were determined by Western blot. Immunohistochemistry was used to determine the location of URAT1 inrenal tubules. Results: Plasma glucose and uric acid levels were higher in the diabetic rats. There was no difference in plasma createnine. URAT1 antibody-positive bands of 27, 31, 50, 62 and 70 kDa were observed in cortex. A similar pattern was observed in medulla with addition of a 44 kDa band. No differences were observed in URAT1 proteins in the cortex between obese and lean rats. In the medulla, expression of the 44 and 50 kDa proteins was higher in lean rats. Expression of 27, 50, 62 kDa URAT1 proteins in the cortex was higher than in the medulla, while expression of the 70 kDa URAT1 was higher in medulla than in cortex. Localization of URAT1 did not differ between groups and included tubules in both cortex and medulla. Conclusions: In male Zucker rats, URAT1 protein expression was observed in both kidney cortex and medulla. Uric acid elevation in the obese group was associated with decreases in the 44 and 50 kDa URAT1 proteins in renal medulla.
基金Supported by the National Natural Science Foundation of China(No.81072915)Science and Technology Planning Project of Guangdong Province,China(No.2012A080201012)Natural Science Foundation of Guangdong Province,China(No.S2012010009032)
文摘Objective： To explore the effect of Compound Tufuling Granules （复方土茯苓颗粒, CTG） on regulating glucose transporter 9 （GLUT9） expression in the kidney to influence the uric acid excretion by the kidney and serum uric acid （SUA） level in hyperuricemia mice. Methods： Sixty Kunming male mice were randomly divided into the control group, model group, benzbromarone group, and CTG high-, middle- and low- dose groups. The yeast extract and uricase inhibition method were used to build hyperuricemia model, and the corresponding drugs were administrated on the 7th day. On the 21st day the 24-h urine was collected, on the 22rid day the blood was collected, the SUA level was detected by uricase colorimetry, and the mRNA and protein expressions of GLUT9 were detected by quantitative real-time polymerase chain reaction and Western blot, respectively. Results： Compared with the model group, the levels of SUA and the mRNA and protein expressions of GLUT9 were significantly decreased, and the fraction excretion of uric acid （FEUA） was significantly increased in the CTG groups and benzbromarone group （all P〈0.05）. There was no significant difference in the above indicators between the CTG high-dose group and benzbromarone group （P〉0.05）. SUA is positively related to the GLUT9 mRNA and protein expressions in the kidney （P〈0.05 or P〈0.01）. Conclusions： CTG can significantly reduce the SUA and increase the FEUA. In addition, CTG can effectively inhibit the mRNA and protein expressions of GLUT9 in the kidney of hyperuricemia mice to inhibit the uric acid re-absorption, promote uric acid excretion and reduce SUA.
