Objective       To determine the effect of curcumin on the differentiation of endogenous neural stem cells (ENSCs) and functional recovery after spinal cord injury (SCI) in rats.       Methods       Seventy-two male Sprague-Dawley (SD) rats were randomly divided into 3 groups

that is

sham-operation group (group A

n=12)

simple injury group (group B

n=30)

and curcumin treatment group (group C

n=30). The rats of group A received only laminectomy. While

those of groups B and C were introduced 70 g closing force aneurysm clip injury at T

9

-T

10

segment of spinal cord for 1 min

and the rats of group C was given 200 mg/kg curcumin intraperitoneally in 30 min after SCI but those of group B were given equivalent amount of normal saline. The Basso

Beattie and Bresnahan (BBB) locomotor rating scale and inclined plane test were used to evaluate rat behavioral consequences in 1 d

and 1

2

4 and 8 weeks after injury. Then the rats were sacrificed and the spinal cord tissue samples were harvested to observe the expression of Nestin

Tuj1

and GFAP/CSPG by immunofluorescence assay. The protein expression of Wnt3a and β-catenin was determined by Western blotting.       Results       BBB locomotor rating scale and inclined plane test showed that the functional recovery was significantly better in group C than group B at each time point from 1week after SCI (

P

0.05). Immunofluorescence assay showed that Nestin positive cells were seen at the vicinity of the lesion site in 1 week after SCI

reached peak at 2 weeks

and obviously decreased at 4 weeks

but there was no significant difference between groups B and C. There were significant more Tuj1-labeled neurons in group C than in group B at each time point. The formation of glia scar surrounding the cavity at the center of lesion site was defined at 4 week after SCI

while the expression of GFAP and CSPG was significant decreased in group C than in group B. Western blotting showed that there was almost no expression of Wnt3a and β-catenin in group A

and that in group C was significant up-regulated compared with group B (

P

0.05).       Conclusion      Curcumin promotes more ENSCs differentiated to neurons by activating Wnt/β-catenin signaling pathway and improves the functional recovery through inhibiting glial scar formation.