title: [Study on cell senescence induced by D-galactose in cultured rat mesenchymal stem cells].
abstract: OBJECTIVE
  To study morphological and biological senescence changes induced by D-galactose in the cultured rat mesenchymal stem cells.
  
  
  METHODS
  After 3rd generations cultured in the DMEM-F12, MSCs were changed into DMEM-F12 medium containing 8 g/L D-galactose and cultured to the 6th generations as the inducement group. The comparison were the 6th generations which was cultured in the DMEM-F12 medium all along, and then identified by surface wave. Using flow cytometer to check the comparisons cell cycle change after swing in with 8 g/L D-galactose within the 4 days. In the first 7 days to draw the growth curve to the two groups. Optical and electronic microscope were used to identify the influences of characteristic morphological of mesenchymal stem cells of the two groups, the influences of biological markers were identified by single cell gel electrophoresis and beta-galactose dye. Results After treatment with D-galactose, the mesenchymal stem cells displayed morphological and biological changes in the cell senescence with the senescent characteristic morphological markers; 85% of the cells were X-gal dye masculine, and the signal cell gel electrophoresis showed DNA damnification. The flow cytometry showed that 90% of the cells stayed in G0/G1, but the cells in S and G2/M almost disappeared. However, the cells in the control group had no such DNA damages.
  
  
  CONCLUSIONS
  D-galactose can induce senescence of the mesenchymal stem cells, and 8 g/L is the best concentration to do so. This study has provided a good model for the research of the mesenchymal stem cells senescence.
authors: Cell Biology Department, Life Science College, Sichuan University, Chengdu Sichuan, 610064, PR China.
authors: Yuzhi
authors: Y
authors: Xing
authors: Linglin
authors: L
authors: Yang
authors: Hong
authors: H
authors: Lin