Bone mesenchymal stem cell-conditioned medium decreases the generation of astrocytes during the process of neural stem cells differentiation

Objectives: The aim of this study was to investigate the effect of bone mesenchymal stem cell (BMSC) conditioned medium (CM) and Bone morphogenetic protein-4 (BMP-4) on the generation of astrocytes during the process of NSCs differentiation. Design: Neural stem cells (NSCs) were grown under different culture conditions. Setting: The First Affiliated Hospital of Anhui Medical University, Hefei, China. Outcome Measures: The study consisted of four groups: NSCs cultured under control conditions (group 1) or with the addition of BMSC-CM (group 2);(BMP-4) (group 3) or both (group 4). The expression of glial fibrillary acidic protein (GFAP) was detected by immunocytochemical staining and Western blotting. Results: The expression of GFAP was higher in Group3 and lower in Group 2 compared to that in Group 1. The expression of GFAP in Group 4 was intermediate between that of Group 2 and Group 3. Conclusions: These results suggest that BMSC-CM can decrease the generation of astrocytes and that the inhibition of the (BMP-4) /Smad1/5/8 signaling pathway may be the underlying mechanism. This phenomenon may be mediated by increasing the expression of Smad6.