title: Anti-hyperuricemia effects of allopurinol are improved by Smilax riparia, a traditional Chinese herbal medicine.
abstract: BACKGROUND
  The roots and rhizomes of Smilax riparia are called "Niu-Wei-Cai" in traditional Chinese medicine (TCM). This botanical has been used in treating the symptoms of gout and other hyperuricemic-related conditions in TCM. Allopurinol is a commonly used medication to treat hyperuricemia and its complications. In this study, we evaluated whether Smilax riparia could enhance allopurinol׳s effects by decreasing the serum uric acid level in a hyperuricemic mouse model induced by potassium oxonate.
  
  
  METHODS
  We examined the effects of allopurinol (5mg/kg) administration alone or in combination with Smilax riparia saponins (SRS, 500 mg/kg) on the serum uric acid (SUA), serum creatinine (SCr) and blood urea nitrogen (BUN) levels in a hyperuricemic mouse model. The effects of allopurinol alone or those of allopurinol plus SRS on the XOD activities were measured. Western blot analysis was used to measure the levels of mURAT1, mGLUT9 and mOTA1 in the mice.
  
  
  RESULTS
  Compared with allopurinol alone, the combination of allopurinol and SRS significantly decreased the serum uric acid level and increased the urine uric acid level (both P<0.05), leading to the normalized serum and urine uric acid concentrations. Data on serum and urine creatinine and BUN supported these observations. The attenuation of hyperuricemia-induced renal dysfunction was linked to the inhibition of both serum and hepatic xanthine oxidase (XOD), the down-regulation of renal mURAT1 and mGLUT9, and the up-regulation of mOAT1.
  
  
  CONCLUSIONS
  The anti-hyperuricemia effects of allopurinol are improved by Smilax riparia co-administration. The results were supported by the measurement of uric acid, creatinine, BUN, XOD, mURAT1, mGLUT9 and mOAT1. Our data may have a potential value in clinical practice in the treatment of gout and other hyperuricemic conditions.
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical, Therapeutics and Diagnostics, College of Pharmacy, Tianjin Medical University, Tianjin 300070, China; Tang Center for Herbal Medicine Research, University of Chicago, Chicago, IL 60637, USA.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Wu
authors.affiliation: Tang Center for Herbal Medicine Research, University of Chicago, Chicago, IL 60637, USA.
authors.forename: Chong-Zhi
authors.initials: CZ
authors.lastname: Wang
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical, Therapeutics and Diagnostics, College of Pharmacy, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Shu-Qing
authors.initials: SQ
authors.lastname: Wang
authors.affiliation: College of Public Health and Communication, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Mi
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical, Therapeutics and Diagnostics, College of Pharmacy, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: He
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical, Therapeutics and Diagnostics, College of Pharmacy, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Tianjin Key Laboratory on Technologies Enabling Development of Clinical, Therapeutics and Diagnostics, College of Pharmacy, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Yan-Wen
authors.initials: YW
authors.lastname: Zhang
authors.affiliation: Tang Center for Herbal Medicine Research, University of Chicago, Chicago, IL 60637, USA.
authors.forename: Samantha
authors.initials: S
authors.lastname: Anderson
authors.affiliation: Tang Center for Herbal Medicine Research, University of Chicago, Chicago, IL 60637, USA. Electronic address: cyuan@dacc.uchicago.edu.
authors.forename: Chun-Su
authors.initials: CS
authors.lastname: Yuan
mesh_terms: D000493:Allopurinol / Q000627:therapeutic use*; D000818:Animals; D001806:Blood Urea Nitrogen; D002851:Chromatography, High Pressure Liquid; D004357:Drug Synergism; D004365:Drugs, Chinese Herbal; D005786:Gene Expression Regulation / Q000187:drug effects; D051246:Glucose Transport Proteins, Facilitative / Q000235:genetics / Q000378:metabolism; D033461:Hyperuricemia / Q000188:drug therapy*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D015394:Molecular Structure; D027362:Organic Anion Transport Protein 1 / Q000235:genetics / Q000378:metabolism; D027361:Organic Anion Transporters / Q000235:genetics / Q000378:metabolism; D008517:Phytotherapy; D012503:Saponins / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D032281:Smilax / Q000737:chemistry*; D014527:Uric Acid / Q000097:blood / Q000652:urine
chemical_list: D004365:Drugs, Chinese Herbal; D051246:Glucose Transport Proteins, Facilitative; D027362:Organic Anion Transport Protein 1; D027361:Organic Anion Transporters; D012503:Saponins; C109687:Slc22a12 protein, mouse; C105033:Slc22a6 protein, mouse; C498775:Slc2a9 protein, mouse; D014527:Uric Acid; D000493:Allopurinol
keywords: Allopurinol; Gout; Hyperuricemia; SRS; Smilax riparia; Smilax riparia saponins