title: [Inhibition effect of osthole on proliferation of rat chondrocytes].
abstract: OBJECTIVE
  To investigate the effects of osthole on chondrocyte proliferation in vitro.
  
  
  METHODS
  Primary rat chondrocytes were isolated from the femoral head of newborn rats using collagenase digestion and cultured in Dulbecco's modified Eagle's medium. The proliferation of primary chondrocytes was assessed in second-passage cultures using cell counting kit-8 and the growth curve was drawn. Type II procollagen gene (Col2a1) expression in chondrocytes was also identified using cell immunofluorescence assay. The second-passage chondrocytes were divided into five groups, including control group and osthole groups at 6.25, 12.5, 25 and 50 μmol/L. The growth property of rat chondrocytes was observed after 24, 48 and 72 h of culture with osthole at corresponding dose. Both protein and mRNA expression of proliferating cell nuclear antigen (PCNA) and cyclin D1 was measured by Western blot and polymerase chain reaction methods.
  
  
  RESULTS
  The second-passage chondrocytes were viable and showed Col2a1 expression in the cytoplasm. The proliferation of rat chondrocytes was inhibited by osthole in a dose-dependent manner. Meanwhile, there were significant decreases in both protein and mRNA expression of PCNA and cyclin D1 in the osthole groups compared with the control group.
  
  
  CONCLUSIONS
  Osthole exhibits inhibitory effect on proliferation of rat chondrocytes by down-regulating PCNA and cyclin D1 expression.
authors.affiliation: Institute of Traumatology and Orthopedics, Shanghai Academy of Traditional Chinese Medicine, Shanghai 201203, China.
authors.forename: Dao-fang
authors.initials: DF
authors.lastname: Ding
authors.forename: Song-pu
authors.initials: SP
authors.lastname: Wei
authors.forename: Xiao-feng
authors.initials: XF
authors.lastname: Li
authors.forename: Xiao-gang
authors.initials: XG
authors.lastname: Zhang
authors.forename: Hong-sheng
authors.initials: HS
authors.lastname: Zhan
authors.forename: Tie-li
authors.initials: TL
authors.lastname: Duan
authors.forename: Yue-long
authors.initials: YL
authors.lastname: Cao
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D024043:Collagen Type II / Q000378:metabolism; D003374:Coumarins / Q000494:pharmacology*; D019938:Cyclin D1 / Q000378:metabolism; D015536:Down-Regulation; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: C511513:COL2A1 protein, rat; C530106:Ccnd1 protein, rat; D024043:Collagen Type II; D003374:Coumarins; D018809:Proliferating Cell Nuclear Antigen; D019938:Cyclin D1; C046627:osthol