| Parkinson’s disease (PD) is a kind of common slow progress of neurodegenerative disease which usually occurs among the elderly population, and that seriously affect the life quality of patients. Base on the deep research of the main pathological mechanism of PD and stem cells, cell transplantation therapy is expected to be one of the ideal ways to treat the disease, but the mechanism of cell transplantation therapy is not yet clear. In this experiment, we use the rat bone marrow mesenchymal stem cells (BMSCs) that be labeled with green fluorescent protein (GFP) as a tracer cell, investigate the cell survival, migration and differentiation of the exogenous source cells in the brain when in treating of rats. Combined with the expression changes of glial fibrillary acidic protein (GFAP) in rat brain, we explore astrocytes (AST) in the treatment of PD model, that provide experimental evidence for cell transplantation therapy of PD in clinical.Part IGFP BMSCs as a tracer cell used in the research on transplantation therapy in Parkinson’s DiseaseThe unilateral stereotaxic intra-striatal single point injection of 6-hydroxydopamine were adopted to establish Parkinson’s disease of rat. The rats were induced to rotate by injected apomorphine(APO) after operation to screen the successful PD rat model. Used the purified GFP BMSCs to positioning transplanted into the damaged striatum of the PD rats. Since two weeks after transplantation, we used APO to induced circling behavior in rats to detect the improvement of behavior after the cell transplanted into PD rat model. We observed the rat brain tissue sections with fluorescence microscopy, track exogenous GFP BMSCs’ survived and migration in the receptors’brain; and detected the specific proteins of the dopaminergic nerve cells-tyrosine acid hydroxylase (TH) by immunohistochemistry expression to research on the rule of differentiation.The number of rotations for the successful PD rats is 10.89±1.08r/min. After transplant the GFP BMSCs into damaged parts of the rat brain, beginning from the first two weeks, the number of rotations gradually reducing, the first eighth weeks dropped to 5.86±1.15r/min. After cell transplantation, exogenous GFP-labeled cells can be seen in the striatum, which can survive at least six weeks; some cells surrounding migrate after transplantation and with a certain direction, and can be migrated to a wide area of the rat brain. Most transplanted BMSCs presented on differentiation, in six weeks after transplantation, not only expressing TH positive cells from GFP, but also appeared a lot of TH expression of endogenous nerve cells around the transplanting needle tract by fluorescence immunohistochemistry, that is BMSCs within the striatum can differentiate into neuron-like cells, and trophic factors were released after differentiation enables enhance the remaining dopamine (DA) neurons.Transplanting BMSCs into PD rat model has a significant effect, the results suggest that the possible mechanisms of cell transplantation in the treatment of PD model is exogenous BMSCs were induce differentiation into dopaminergic neurons in ihe brain, and the part of them to replace the function of the damaged dopaminergic neurons. By producing certain nutritional factors, the transplanted exogenous BMSCs effective recovery of DA neurons in animal models or let more endogenous neuron-like cells into the synthesis of dopamine cells specifically, thus improving symptoms of PD model. GFP BMSCs due to autofluorescence, to facilitate the observation the survival, migration and differentiation after transplantation of exogenous cell in the receptors brain, as a tracing cell when cells transplantation has extensive prospects.Part ⅡThe affects of GFAP express of astrocytes in the brain of rat after BMSCs transplantation for Parkinson’s diseaseIn this study, the detection of glial fibrillary acidic protein (GFAP) expression explore the brain astrocytes (AST) in BMSCs transplantation in the treatment of PD functions, we extracted total RNA and protein of the normal rats, the PD model rats and the PD model rats which transplanted 4 weeks and 8 weeks of treatment by BMSCs of in rat brain respectively, then measured the expression levels of GFAP mRNA and protein in the brain by real-time PCR and western blot.The results showed that GFAP mRNA expression level of the damaged side in model rats was increase 0.33-fold than the right brain in normal rats, the protein expression of GFAP is also higher than normal rats, but TH protein content has decreased; after BMSCs transplantation therapy, GFAP mRNA expression in brain gradually decreased. After 4 weeks, the expression of the brain is decrease 0.37-fold than the rat model, but the GFAP protein was increased, TH protein expression was also increased. After eight weeks, the expression of GFAP mRNA of right brain is reduce 0.70-fold than the rat model, and the GFAP protein was decreased, while the TH protein expression was increased, and finally were close to the normal expression level in nonnal rat brain. Immunofluorescence staining was seen that TH cells were significantly increased around the exogenous, neuron-like cells which instead of dopaminergic neurons also increased compared with model rats.During BMSCs transplantation for treatment of PD rats, immunohistochemistry of GFAP were negative in the brain of normal animal, but in the process of the preparation of PD model, astrocyte activation, and enhanced the expression of GFAP emerged as a reactivity astrocyte, whereas the expression of GFAP was negative after repair. GFAP is unique logo of astrocyte activation, therefore, researching the changes of astrocytes treatment to explore of Parkinson’s mechanism in the treatment of PD rats is important. As a support cell, astrocyte can accurately guide neuronal migration to the injury site in the brain, and secrete large amounts of nutritional factors, promote the formation of DA neurons and repair the DA neural pathways of the substantia nigra-striatum, one of the most important nutritional factors is GFAP, it has a strong protective effect for vertebrates, and exercise important functions in the central nervous system (CNS). Therefore, AST makes a huge contribution to the exogenous cell migration in the brain, and provide the new ideas for the study of mechanism of BMSCs transplantation for the treatment of PD. |
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