title: Rapamycin and 3-methyladenine regulate apoptosis and autophagy in bone-derived endothelial progenitor cells.
abstract: BACKGROUND
  Mammalian target of rapamycin (mTOR) is involved in a caspase independent form of programmed cell death called autophagy. The aim of this research was to investigate the effects of rapamycin and 3-methyladenine (3-MA) on autophagy, proliferation, apoptosis, and cell-cycle parameters of rat bone marrow-derived endothelial progenitor cells (EPCs).
  
  
  METHODS
  Mononuclear cells isolated from rat bone marrow were treated with rapamycin (0.01, 0.1, 1, or 10 µg/L) or 3-MA (1.25, 2.5, 5, or 10 mmol/L) for 24 hours. Expression of the autophagy marker protein LC3-II was analyzed by Western blotting. Apoptosis and cell-cycle progression were analyzed by flow cytometry. Cell proliferation was measured using the MTT assay.
  
  
  RESULTS
  Rapamycin treatment of EPCs induced apoptosis and autophagy and inhibited proliferation and cell-cycle progression in a dose-dependent manner. Treatment with 5 mmol/L 3-MA promoted cell proliferation; in contrast, treatment with 10 mmol/L 3-MA promoted apoptosis and induced S-phase arrest.
  
  
  CONCLUSIONS
  Rapamycin treatment of EPCs induced apoptosis and autophagy. Low concentrations of 3-MA had no significant effect on the proliferation and apoptosis of EPCs; The 5 mmol/L group promoted cell proliferation, but had no effect on the apoptosis; the 10 mmol/L group inhibited the proliferation and promoted apoptosis through the cell cycle.
authors.affiliation: Department of Vascular Surgery, the Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Feng-rui
authors.initials: FR
authors.lastname: Lei
authors.forename: Xiao-qiang
authors.initials: XQ
authors.lastname: Li
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.forename: Ren-da
authors.initials: RD
authors.lastname: Zhu
authors.forename: Qing-you
authors.initials: QY
authors.lastname: Meng
authors.forename: Jian-jie
authors.initials: JJ
authors.lastname: Rong
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy / Q000187:drug effects*; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D051381:Rats; D020123:Sirolimus / Q000494:pharmacology*
chemical_list: C025946:3-methyladenine; D000225:Adenine; D020123:Sirolimus