The Effect On Nerve Growth Factor Of Bone Marrow Stromal Cells To Treat Brain Ischemia In Rat

ObjectiveTo test the effect and mechanism of intravenously injected bone marrow stromal cells ( BMSCs) on neurological functional deficits after stroke in rats, provide the theoretical basis for clinic therapy.MethodsForty - five wistar rats were randomly assigned in 3 groups: BMSCs treated group, saline group, nothing group, there were 15 rats in each group. Temporary ischemia of the middle cerebral artery occlusion ( MCAO) for 1 hour was induced by the modified Longa suture occlusion technique. Primary cultures of Bone Marrow cells were obtained from tibias and femurs of the mice (14 day). BMSCs were havested, cultured in vitro by the method of Fredenshtein's and i-dentified with immunocytochemistry. BMSCs was marked with BrdU one day before transplantation. We choose BMSCs of 3 -5 passages. The animals of experimental group (n = 15) were injected by the tail vein with 3 × 10~6BMSCs marked with BrdU, the animals of saline group (n = 15) were injected with 1 ml saline, the animals of the other control group (n = 15) were injected with nothing. We assess improvement of neurological function at 3, 7, 14 day after cerebral ischemia. The animals of different groups were anaesthetized ,then cardiac perfused, fixed, embedded and cut into slices(7μm). Immunohistochemistry staining wasadministered by the method of SABC. The first antibody was rabbit - anti - NGF ( dilution of 1:200) and rabbit - anti - BrdU (dilution of 1:200). The second antibody was biotinilated goat - anti - fat IgG and goat - anti - rabbit IgG respectively. Use DAB to show colour. We detect the expression of the NGF at 3, 7, 14 day of cerebral ischemic reperfusion by microimage analysis system. SPSS11. 0 statistical software was used to analyze significant difference between the three groups.ResultsComparing with the two control groups, no striking difference at the 3,7, and 14 day after stroke (P > 0.05). Significant recovery of neurological function was found in rats treated with BMSCs comparing with the other two control groups at 7 and 14 day after ischemia( P < 0.05). There are a great deal of BrdU Positive cells within ischemic area in animals of tranaplantation of BMSCs, and a few of diffusible BrdU Positive cells in the other hemisphere were found. The expression of NGF was the most at 7 day after MCAO at different time points. No obvious difference between the saline control group and the single control group at different time points (P > 0. 05) , but the expression of NGF was significant different with the other two control groups at the 3 time points ( P <0.05) .ConclusionsWe injected BMSCs into the rats'vein at a day after temporary ischemia of the middle cerebral artery occlusion (MCAO) for 1 hour. Intravenously injected BMSCs is simple and effective on improvement of neurological functional deficits after stroke in rats. The result of this experiment shows : comparing the group (inject BMSCs into vein) with the other two control groups, the expression of NGF at each time point after infarction increased obviously (P < 0.05). The increase of NGF in the ischemic tissue play an important role on neurological re-...