Evidence suggests that neurogenesis occurs in the adult mammalian brain, and that various stimuli, for example,
ischemia/
hypoxia, enhance the generation of neural progenitor cells in the subventricular zone (SVZ) and their migration into the olfactory bulb. In a mouse
stroke model, focal
ischemia results in activation of neural progenitor cells followed by their migration into the ischemic lesion. The present study assessed the in vivo effects of
cilostazol, a type 3
phosphodiesterase inhibitor known to activate the cAMP-responsive
element binding protein (CREB) signaling, on neurogenesis in the ipsilateral SVZ and peri-
infarct area in a mouse model of transient
middle cerebral artery occlusion. Mice were divided into
sham operated (n=12), vehicle- (n=18) and
cilostazol-treated (n=18) groups. Sections stained for
5-bromodeoxyuridine (
BrdU) and several neuronal and a glial markers were analyzed at post-
ischemia days 1, 3 and 7.
Cilostazol reduced brain ischemic volume (P<0.05) and induced earlier recovery of
neurologic deficit (P<0.05).
Cilostazol significantly increased the density of
BrdU-positive newly-formed cells in the SVZ compared with the vehicle group without
ischemia. Increased density of doublecortin (DCX)-positive and
BrdU/DCX-double positive neural progenitor cells was noted in the ipsilateral SVZ and peri-
infarct area at 3 and 7 days after focal
ischemia compared with the vehicle group (P<0.05).
Cilostazol increased DCX-positive phosphorylated CREB (pCREB)-expressing neural progenitor cells, and increased
brain derived neurotrophic factor (
BDNF)-expressing astrocytes in the ipsilateral SVZ and peri-
infarct area. The results indicated that
cilostazol enhanced neural progenitor cell generation in both ipsilateral SVZ and peri-
infarct area through CREB-mediated signaling pathway after focal
ischemia.