Study On The Effect Of Transplanting NGF Gene Modified Bone Marrow Mesenchymal Stem Cells Into The Brains Of Rats With Vascular Dementia

ObjectiveTo study the effect of transplanting NGF gene modified bone marrow stem cells into the brains of rats with vascular dementia.MethodsBMSCs isolated and amplified in vitro were transfected by Ad-GFP-NGF or Ad-GFP.Rats received permanent bilateral carotid arteries ligation to establish VaD models and were randomly divided into four groups.Group A(sham group);Group B(PBS group):Rats were intravenously injected 1 ml PBS 1 week after ligation; Group C(BMSCs group):Rats were intravenously injected 4×10~6BMSCs transfected by Ad-GFP 1 week after ligation;Group D(NGF gene modified group):Rats were intravenously injected 4×10~6BMSCs transfected by Ad-GFP-NGF 1 week after ligation.4 weeks later,behavioral abnormalities were observed by Morris water maze test and the expressions of synaptophysin,NGF and NMDAR1 in neurons of hippocampus were detected by immunohistochemistry technique.TUNEL was used to identify apoptotic cells in hippocampi of the rats.The expression of NGF in the BMSCs modified by NGF gene was detected by western blot.Results1.Either in the NGF group or in the BMSC group,the green fluorescence could be deteeted in the hippocampus area 4weeks after transplantation.2.Morris water maze test showed that during the second to the fifth day,the average escape latency either in the BMSCs group or in the NGF group was shorter than that in the PBS group(P<0.05),between the BMSCs group and the NGF group,the average escape latency was shorter in the latter(P<0.05).On the sixth day, the traversing times(through the fiat) in the BMSCs group or in the NGF group was more than those in the PBS group(P<0.05),between the BMSCs group and the NGF group,the traversing times were even more in the latter(P<0.05).3.HE Staining:The deeper stain and condensed nuclei with enlarged intercellular space could be observed in the hippocampus of VaD group;the exposure of either BMSCs or NGF gene modified BMSCs improved the change;and the condition in the NGF group was even better.4.TUNEL analysis:The apoptosis of nerve cell in NGF group and BMSCs group were significantly less than that in the PBS group(P<0.05),compared with BMSC group,The apoptosis of nerve cell in NGF group was much less(P<0.05).5.Either in NGF group or in BMSCs group,the expression of NMDAR1 was significantly lower than that in the PBS group(P<0.05),and the expressiom in NGF group was much lower than that in the BMSC group(P<0.05).6.Either in NGF group or in BMSCs group,the expression of synaptophysin was significantly higher than that in the PBS group(P<0.05),and the expressiom in NGF group was higher than that in the BMSC group(P<0.05).7.Either in NGF group or in BMSCs group,the expression of NGF was significantly higher than that in the PBS group(P<0.05),and the expressiom in NGF group was higher than that in the BMSC group(P<0.05).8.Western blot:The expression of NGF in the NGF gene modified BMSCs was higher than that in the unmodified BMSCs.Conclusions1.The injection of NGF gene modified BMSCs could improve learning and memory ability of VaD rats.2.The injection of NGF gene modified BMSCs could reduce apoptosis in hippocampus.3.The injection of NGF gene modified BMSCs made synaptophysin expression increased in VaD rats.4.The injection of NGF gene modified BMSCs could reduce the expression of NMDAR1 in rats with vascular dementia.5.The injection of NGF gene modified BMSCs made NGF expression increased in VaD rats.6.The effect of transplanting NGF gene modified BMSCs into the brains of rats with vascular dementia was better that of transplanting BMSCs only.