title: [INFLUENCE OF INHIBITION OF ACTIN POLYMERIZATION ON ADIPOGENIC DIFFERENTIATION OF RAT Achilles-DERIVED TENDON STEM CELLS IN VITRO].
abstract: OBJECTIVE
  To investigate the effect of cytoskeleton modification on the adipogenic differentiation of rat Achilles-derived tendon stem cells (TSCs) in vitro.
  
  
  METHODS
  TSCs were isolated from the tendon tissue of male Sprague Dawley rats (aged 3 weeks) by enzymatic digestion method and cultured for 3 passages. After the 3rd passage cells were cultured with DMEM medium containing 15% fetal bovine serum and cytochalasin D (CYD) at the concentrations of 0, 50, 100, 500, and 1 000 ng/mL, the cell survival condition and morphology changes were observed by inverted phase contrast microscope, the cytoskeleton was observed through fibrous actin (F-actin) staining, and the ratio of F-actin/ soluble globular actin (G-actin) was detected and calculated through Western blot. According to the above results, the effective concentration of CYD was selected and used for next experiments. After TSCs were cultured for 3 and 7 days respectively with adipogenic induction media (induction group), adipogenic induction media containing CYD (CYD+induction group), ordinary medium (ordinary group), and ordinary medium containing CYD (CYD+ordinary group), the real-time quantitative PCR (qRT-PCR) and Western blot were carried out to measure the mRNA and protein expressions of adipogenic differentiation-related markers, including peroxisome proliferator-activated receptor y (PPARγ), lipoprotein lipase (LPL), and fatty acid binding protein (aP2).
  
  
  RESULTS
  The final CYD concentration of 100 ng/mL can inhibit effectively G-actin polymerization into F-actin, but could not affect TSCs survival, which was used for next experiments. qRT-PCR and Western blot suggested that the mRNA expressions of PPARγ, LPL, and aP2 and the protein expressions of PPARγ and aP2 were increased significantly in the CYD+induction group at 3 and 7 days when compared with the induction group (P < 0.05). In the CYD+ordinary group, there still was a significant increase in the mRNA expressions of PPARγ, LPL, and aP2 when compared with the ordinary group (P < 0.05).
  
  
  CONCLUSIONS
  Inhibition of F-actin polymerization can increase adipogenic differentiation of rat Achilles-derived TSCs in vitro, and cytoskeleton modification is a pre-requisite for TSCs differentiation into adipocytes, which might have important implications for the mechanism research of tendinopathy.
authors.forename: Bo
authors.initials: B
authors.lastname: Chen
authors.forename: Kanglai
authors.initials: K
authors.lastname: Tang
authors.forename: Jiqiang
authors.initials: J
authors.lastname: Zhang
authors.forename: Yupeng
authors.initials: Y
authors.lastname: Guo
authors.forename: Xiangzhou
authors.initials: X
authors.lastname: Liu
authors.forename: Youxin
authors.initials: Y
authors.lastname: Shi
mesh_terms: D000125:Achilles Tendon / Q000166:cytology*; D000199:Actins / Q000494:pharmacology*; D017667:Adipocytes / Q000166:cytology*; D000818:Animals; D002417:Cattle; D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D006801:Humans; D008297:Male; D058105:Polymerization; D051381:Rats; D017207:Rats, Sprague-Dawley; D013234:Stem Cells / Q000166:cytology*; D052256:Tendinopathy
chemical_list: D000199:Actins