title: Psoralen activates cartilaginous cellular functions of rat chondrocytes in vitro.
abstract: BACKGROUND
  Psoralen, an active ingredient from Fructus Psoraleae (FP), is used in Traditional Chinese Medicine (TCM) to treat bone diseases. However, the effect of psoralen on cartilage is unknown.
  
  
  OBJECTIVE
  To investigate the effects of psoralen on chondrocytes isolated from rats.
  
  
  METHODS
  Chondrocytes were treated with different concentrations of psoralen (1, 10, and 100 μM) in vitro at 3-d and 9-d intervals. MTS assay, Alcian blue colorimetry, western blotting, and qRT-PCR, respectively, were used to evaluate the effects of psoralen on cell viability, glycosaminoglycan (GAG) synthesis, collagen synthesis, and cartilage-specific gene expression.
  
  
  RESULTS
  Psoralen dosages of 1-10 μM exhibited low cytotoxicity toward chondrocytes. However, a dosage of 100 μM suppressed the proliferation of chondrocytes. Different concentrations of psoralen treatments on chondrocytes revealed that GAG and Type II collagen synthesis increased, especially at 100 μM, by 0.39-fold and 0.48-fold, respectively, on day 3, and by 0.51-fold and 0.56-fold, respectively, on day 9. Similarly, gene expression of Type II collagen, aggrecan, and SOX-9 were all up-regulated on days 3 and 9, particularly aggrecan which increased significantly by 9.37-fold and 7.32-fold at 100 μM. Additionally, Type I collagen was inhibited both in gene expression and in protein synthesis.
  
  
  CONCLUSIONS
  The results showed that psoralen promotes cartilaginous extracellular matrix (ECM) synthesis, as well as increased cartilaginous gene expression, and it may be a useful bioactive component for activating the cartilaginous cellular functions of chondrocytes.
authors.affiliation: National Innovation and Attracting Talents "111" Base, Bioengineering College, Chongqing University , Chongqing , PR China .
authors.forename: Kang
authors.initials: K
authors.lastname: Xu
authors.forename: Xin
authors.initials: X
authors.lastname: Pan
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Sun
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Lucy
authors.initials: L
authors.lastname: Njunge
authors.forename: Li
authors.initials: L
authors.lastname: Yang
mesh_terms: D000818:Animals; D002356:Cartilage / Q000166:cytology* / Q000187:drug effects* / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D019902:Chondrocytes / Q000187:drug effects* / Q000502:physiology; D017077:Culture Media, Conditioned / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005363:Ficusin / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D017077:Culture Media, Conditioned; D005363:Ficusin
keywords: Cartilage; Fructus Psoraleae; collagen; genes; glycosaminoglycan