Curcumin promotes the proliferation, invasion of neural stem cells and formation of neurospheres via activating SDF-1/CXCR4 axis.

Curcumin is an active ingredient isolated from the rhizomes of Curcuma longa Linn with remarkably non-toxic bioavailability. This is an in vitro study. In this study, we explored the effects of curcumin on the proliferation, migration and neurogenesis of neural stem cells (NSCs). Primary NSCs were isolated from embryonic day 14 rats and then treated with curcumin and/or stromal derived factor-1 (SDF-1). NSCs showed an SDF-1-dependent proliferation and migration. Further results showed that curcumin and SDF-1 both promoted NSCs proliferation, migration and the formation of neurospheres. In addition, Curcumin up-regulated the expression of SDF-1 and promoted the formation of SDF-1/CXCR4 complex in NSCs. The western blot results showed that the phosphorylation levels of ERK, JNK, MAPK, NF-kB and Akt were up-regulated by curcumin. In contrast, the administration of CXCR4 inhibitor AMD3100 could offset the effect of curcumin. These results suggested that curcumin promoted the NSCs proliferation, migration and formation of neurospheres via SDF-1/CXCR4 in NSCs.