Effects of Panax Notoginseng Saponins on Proliferation and Differentiation of Rat Hippocampal Neural Stem Cells

We aimed to investigate the effects of Panax notoginseng saponins (PNS) on proliferation, differentiation and self-renewal of rat hippocampal neural stem cells (NSCs) in vitro. Rat hippocampal NSCs were isolated from post-natal day 1 (P1) rats and cultured in a serum-free medium. The neurospheres were identified by the expressions of nestin, class III β-tublin (Tuj-1) and glial fibrillary acid protein (GFAP). The cells were given PNS and subjected to oxygen glucose deprivation (OGD) as an in vitro model of brain ischemia reperfusion. The proliferation of NSCs was determined by MTT colorimetry, nestin/BrdU immunofluorescent double-labeling and RT-PCR. Differentiation of NSCs was assessed by immunofluorescent double-labeling of nestin/BrdU, nestin/vimentin, and nestin/Tuj-1. The primary cells and the first two passages of cells formed certain amount of neurospheres, the cells derived from a single cell clone also formed neurospheres. Nestin, BrdU, GFAP and Tuj-1-positive cells appeared in those neurospheres. Compared to the control group, PNS significantly promoted NSC proliferation and the expression of nestin/BrdU, and also enhanced Tuj-1, vimentin, and nestin mRNA expressions in hippocampal NSCs. PNS significantly increased area density, optical density and numbers of nestin/BrdU, nestin/vimentin, and nestin/Tuj-1 positive cells following OGD. These results indicate that PNS can promote proliferation and differentiation of hippocampus NCSs in vitro after OGD, suggesting its potential benefits on neurogenesis and neuroregeneration in brain ischemic injury.