Objective      To investigate the effect of curcumin on expression of Wnt/β-catenin signaling pathway in neural stem cells in vitro.       Methods      Neural stem cells were isolated from anterior two-thirds brains of fetal Sprague-Dawley (SD) rats (14.5 d after pregnancy). The neural stem cells were passaged for 3 times by half media repla

cement and identified by cellular immunofluorescence assay. After 3 passages

cells were seeded in the media without bFGF or EGF. Then

cells were treated in different groups: control group

IWR-1 (a specific inhibitor to Wnt signaling pathway

10 μmol/L) group

500 nmol/L curcumin group

IWR-1+ curcumin 500 nmol/L group and DMSO group. We measured Wnt3a and β-catenin expression levels by Western blotting and RT-PCR separately.       Results      Western blotting results showed that Wnt3a and β-catenin expression levels had significant increases in the curcumin group (

P

0.05)

but were decreased in the IWR-1 group and IWR-1+curcumin group (

P

0.05). RT-PCR results showed that the expression levels of Wnt3a and β-catenin were increased in the curcumin group but decreased in the IWR-1 group (

P

0.05)

showing similar change pattern to the Western blot results.       Conclusion      Curcumin activates the classic Wnt/β-catenin signaling pathway in neural stem cells.