title: [Butenolide induces apoptosis of cultured chondrocytes: study of its mechanism].
abstract: OBJECTIVE
  To observe cell apoptosis and Bcl-2 and Bax expression changes of chondrocytes induced by butenolide (BUT) and the inhibitory effect of selenium against BUT-induced chondrcyte apoptosis, to gain insights into the mechanism by which BUT induces chondrcyte apoptosis.
  
  
  METHODS
  Cartilage tissue reestablished from human fetal articular chondrocytes in vitro were treated with BUT at the concentrations of 0.1, 1.0 and 5.0 microg/ml and with the protective factor selenium. TUNEL method was used to detect chondrocyte apoptosis, which was quantified by flow cytometry. Immunohitochemistry was performed to analyze the expression of Bcl-2 and Bax in the reestablished cartilage tissue.
  
  
  RESULTS
  BUT exposure induced chondrocyte apoptosis, and the apoptosis rate increased with the concentration increment of BUT from 0 to 1.0 mg/ml, resulting also increased positive expression rate of Bcl-2 and Bax(P<0.05). The apoptosis rate of chondrocytes in BUT+ selenium group was significantly lower than that of BUT groups (P<0.05), as was the positivity rate of Bcl-2 and Bax expression (P<0.05).
  
  
  CONCLUSIONS
  BUT induces chondrocyte apoptosis in positive relation with BUT concentration (from 0 to 1.0 mg/ml) and causes increased expressions of Bcl-2 and Bax. Selenium can inhibit the chondrocyte apoptosis induced by BUT.
authors.affiliation: Institute of Pharmacology and Toxicology, Academy of Military Medical Sciences, Beijing 100850, China.
authors.forename: Shi-jie
authors.initials: SJ
authors.lastname: Wang
authors.forename: Xiong
authors.initials: X
authors.lastname: Guo
authors.forename: Yin-gang
authors.initials: YG
authors.lastname: Zhang
authors.forename: Feng-ling
authors.initials: FL
authors.lastname: Ren
authors.forename: Shuang-qing
authors.initials: SQ
authors.lastname: Peng
authors.forename: Jun-ling
authors.initials: JL
authors.lastname: Cao
authors.forename: Zhong-li
authors.initials: ZL
authors.lastname: Shi
authors.forename: Zeng-tie
authors.initials: ZT
authors.lastname: Zhang
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects*; D006801:Humans; D020287:In Situ Nick-End Labeling; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D012643:Selenium / Q000494:pharmacology; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; C004511:butenolide; D012643:Selenium; D015107:4-Butyrolactone