title: Uricosuric and nephroprotective properties of Ramulus Mori ethanol extract in hyperuricemic mice.
abstract: BACKGROUND
  Ramulus Mori, the branch of Morus alba, is widely used in traditional Chinese medicine prescriptions to treat gout and hyperuricemia.
  
  
  OBJECTIVE
  To evaluate the uricosuric and nephroprotective effects of ethanol extract of Ramulus Mori (ERM) and explore its possible mechanisms in hyperuricemic mice.
  
  
  METHODS
  HPLC analysis was employed to determine the main constituents. Hyperuricemia was induced by potassium oxonate (250 mg/kg) in male mice. ERM (10, 20 and 40 mg/kg) was orally administered to hyperuricemic and normal mice for 7 days. Serum and urine levels of uric acid, creatinine and blood urea nitrogen (BUN) were measured. Simultaneously, renal mRNA and protein levels of mouse urate transporter 1 (mURAT1), glucose transporter 9 (mGLUT9), organic anion transporter 1 (mOAT1) and organic cation/carnitine transporters (mOCT1/2, mOCTN1/2) were analyzed by RT-PCR and Western blotting methods.
  
  
  RESULTS
  ERM mainly contained mulberroside A, oxyresveratrol, 4-hydroxycinnamic acid, resveratrol, 7-hydroxycumarin and morin. ERM significantly reduced serum urate levels and increased 24h-urine urate excretion and fractional excretion of uric acid in hyperuricemic mice. It effectively restored oxonate-induced expression alteration of renal mURAT1, mGLUT9 and mOAT1, resulting in urate excretion enhancement. Moreover, ERM decreased serum creatinine and BUN levels and increased creatinine clearance, and up-regulated expression of mOCT1/2 and mOCTN1/2, contributing to kidney function improvement in this model.
  
  
  CONCLUSIONS
  These results suggest that ERM exerts the uricosuric and nephroprotective actions by the regulation of these renal organic ion transporters in hyperuricemic mice, and provide scientific support for the empirical use of Ramulus Mori.
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093, PR China.
authors.forename: Yun-Wei
authors.initials: YW
authors.lastname: Shi
authors.forename: Cai-Ping
authors.initials: CP
authors.lastname: Wang
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
authors.forename: Yuan-Li
authors.initials: YL
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.forename: Ru-Wei
authors.initials: RW
authors.lastname: Wang
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Ye
authors.forename: Lin-Shui
authors.initials: LS
authors.lastname: Hu
authors.forename: Ling-Dong
authors.initials: LD
authors.lastname: Kong
mesh_terms: D000818:Animals; D001806:Blood Urea Nitrogen; D003404:Creatinine / Q000097:blood / Q000652:urine; D000431:Ethanol / Q000737:chemistry; D033461:Hyperuricemia / Q000188:drug therapy* / Q000378:metabolism; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008297:Male; D026901:Membrane Transport Proteins / Q000378:metabolism; D051379:Mice; D031625:Morus; D008517:Phytotherapy; D010936:Plant Extracts / Q000032:analysis / Q000627:therapeutic use*; D020011:Protective Agents / Q000032:analysis / Q000627:therapeutic use*; D012997:Solvents / Q000737:chemistry; D014527:Uric Acid / Q000097:blood / Q000652:urine
chemical_list: D026901:Membrane Transport Proteins; D010936:Plant Extracts; D020011:Protective Agents; D012997:Solvents; D014527:Uric Acid; D000431:Ethanol; D003404:Creatinine