Abstract
The central nervous system in the embryo develops around the cerebrospinal fluid (CSF), which regulates cell proliferation and differentiation. Neurogenesis has been also reported in the subventricular zone (SVZ), which is close to CSF, after stroke in rats. In this study, CSF extracted following stroke in rats was added to bone marrow stromal cell (MSC) culture in vitro, and the proliferation and differentiation of MSCs were studied. Primary cultures of MSCs were obtained from 7-week-old Lewis rats and incubated in a plastic tissue culture flask. CSF was retrieved from other rats 48 hrs after 0, 15 and 75 min after middle cerebral artery occlusion (MCAO). CSF from these three groups were added to respective MSC culture solutions, and the cells were then incubated for 72 hrs. Western blots of the extracellular signal-regulated kinase-1 and -2 (Erk1/2) were obtained just after the CSF induction. The expressions of CD34, CD45, CD90 and CD108 were assessed by flow cytometric analysis. The proliferation of MSCs was accelerated by the addition of post-stroke CSF, especially in the 15-min MCAO, in a dose-dependent manner. The morphology and surface antigens of the cells were maintained in all groups. Phosphorylated-Erk1/2 was elevated in all the CSF-treated groups, although this effect was more enhanced in the 15-min MCAO group. Our data indicate that the addition of post-stroke CSF to the primary medium stimulated the proliferation of MSCs, and that these MSCs maintained their characteristics through the p-Erk1/2 pathway. These results suggest that use of post-stroke CSF as a component of culture media could facilitate the autologous transplantation of MSCs.
