The Effects Of Transplanted BDNF Overexpressing Neural Stem Cells On Hippocampus Microenvironment

ObjectiveTo evaluate the effects of neural stem cells(NSCs)overexpressing brain-derived neurotrophic factor(BDNF)on the hippocampal microenvironment after transplantation into a rat model of radiation-induced brain injury.Methods1?Hippocampal neural stem cells were isolated from fetal rat brain and cultured and identification of neural stem cell surface markers.2?NSCs were infected with GFP-lentivirus and GFP-BDNF-lentivirus.3?Establishment of an animal model of radiation-induced brain injury:Male SD rats of 1 month old were selected as experimental animals,and 4MeV electron beam was selected,and the dose of 20Gy was used to model the animal model of radiation-induced brain injury.4?SD rats were randomized into four groups:control group(C group),irradiated group(IR group),GFP-modified NSCs transplantation group after irradiation(IR+NSCs group),and GFP-BDNF modified NSCs transplantation group after irradiation(IR+BDNF-NSCs group).NSCs were transplanted into the bilateral hippocampus of rats one month after whole brain irradiation at a single dose of 20Gy.5?The expressions of BDNF,glial-derived neurotrophic factor(GDNF)and nerve growth factor(NGF)in hippocampus were detected by Western-blot at 2 and 8 weeks after transplantation.The activation of microglia was observed by immunofluorescence.ResultsAt 2 and 8 weeks after transplantation,the expression of BDNF and NGF protein in hippocampus of R+BDNF-NSCs group was significantly higher than that of R group.The activated microglia in the R+NSCs group and the R+BDNF-NSCs group showed no reduction compared with the R group.ConclusionThe transplantation of NSCs overexpressing BDNF promotes the production of BDNF and NGF,which improves the hippocampal microenvironment to some extent.