Transplantation Of Bone Marrow Mesenchymal Stem Cells In Treatment Of Alzheimer's Disease In Rats

OBJECTIVE:To study the effects of bone marrow mesenchymal stem cells (BMSCs) on learning and memory ability in Alzheimer's disease mouse modle induced by amyloid-β1-40 injection,and to explore the therapeutical and potential mechanism.This will provide more therapy foundation in clinical application on Alzheimer's disease and help to discover effective methods.METHODS:BMSCs were separated with density gradient centrifugation and cell attachment.10 mg/L BrdU was used for labeling before BMSCs transplantation. AD model was incuced by injecting amyloid-β1-40 into the bilateral Hippocampus with adult male SD rats, and then divided them into control group,AD group and transplantation group randomly. AD group and transplantation group was incuced by injecting 5μL amyloid-β1-40(10μg) into the bilateral hippocampus of rats, in the control group, an equal volume of saline was utilized.3 weeks later,implant the BMSCs into the transplantation group in the same method. In the control group and AD group, the rats were left intact. The learning and memory ability of rats were evaluated with Morris Water Maze. Rats were sacrificed after 2 months. Observe the immunohistochemistry double-staining cells(Brdu+ NSE and Brdu+ GFAP) and the immunohistochemistry single-staining cells(nestin), to find the situation of BMSCs after transplation.RESULTS:By the way of density gradient centrifugation combine with adherence screening method to separate bone marrow mesenchymal stem cells, subsequently transfer of culture and amplification and differentiate in vitro. The separated cells was detected by flow cytometer, result display the cells express CD90 and CD29, accord with the characteristics of BMSCs,such as the form and cell-surface marker.The cells possess favourable self-renewal ability and multi-directional differentiation potential, confirm the cells we separated is BMSCs.AD model was incuced by injecting amyloid-β1-40 into the bilateral Hippocampus.The escape latency of hidden platform in the AD group were delayed significantly. Suggest that the model was successful,and provide eligible conditions for the transplantation of bone marrow mesenchymal stem cells in AD rats. The escape latency of hidden platform in the AD group was delayed and the platform spanning frequency was decreased significantly as compare with the control group(P<0.05),suggest the model was successful,and provide eligible conditions for BMSCs transplantation at the later stage. The escape latency of hidden platform in the transplantation group was shorten and the platform spanning frequency was increased significantly as compare with the AD group(P<0.05).Double-staining cells of immunohistochemistry could be found at the center of damage site(bilateral Hippocampus) and the surrounding site in rats of the transplantation group.CONCLUSION:Bone marrow mesenchymal stem cells could separated and amplification in vitro. AD model incuced by injecting amyloid-β1-40 into the bilateral hippocampus is stable,this method can be used for the treatment of AD in rats.Bone marrow mesenchymal stem cells can differentiated into neuron-like and glial cell-like cells after transplantation, have effect of improving spacial learning-dysmnesia of AD rats. Transplantation of BMSCs is safety and effective, suggesting it can be a new way for AD.