| Objectives: Spinal cord injury is a serious complication of the disease of spine, often results in severe dysfunctions of motor and sensory under the injury stage.SCI continues to be a devastating injury to themselves and their families, they bear the biggest burden of the disease, such as an enormous financial, psychological and emotional cost to them and to society. With technological advances in cell technology, stem cell-based therapy became a reliable and effective method. An array of MSCs from many sources with new and promising methods are being used to improve the function after SCI. MSCs are self-renewing, multi-potent progenitor cells with the capacity to differentiate into several distinct mesenchymal lineages. Because the low survival and differentiation rate, its experimental study and further application is limited. Micro-RNA widely exists in biological body, regulates the gene expression and individual development. Several trials have investigated the efficacy of micro-RNA in differentiate of stem cells. Today, we research the effects of mi RNA-let-7b-modified bone mesenchymal stem cells transplantation on the repair of nerve in rats with spinal cord injuryMethods: 60 SD rats were randomly divided into three groups, each group including 20 rats:control group(n=20), BMSCs group(n=20), and micro-RNA group(n=20). the control group received the physical saline in the injury region,1 week after the SCI model were established, and BMSCs infected with empty virus were injected in the same place in BMSCs group, and the rats of mi RNA group were treated with the BMSCs transfect with micro RNA-let-7b lentiviral vector. The neurological functions were evaluated, using the Basso-Beattie-Bresnahan(BBB) scale, 3 days、1week、2 weeks、 4 weeks and 8 weeks after manufacturing model. Neuro-filament 200(NF-200) and glial fibrillary acidic protein(GFAP)of the spinal cord were detected. Using SPSS19.0 software for statistical analysis All values were conformed as mean±standard deviation( sx ±). Statistical analysis of data was performed using a one-way analysis of variance(ANOVA); data were performed using t test when homogeneity of variance. Using Tamhane’s T2 test when heterogeneity of variance. Statistical significance was assumed if P < 0.05.Results: 1. All groups of rats have severe hind limbs dysfunction after operation, and compare with the scores of three groups, there was no significant(P>0.05). After the transplantation, BBB score of rats 3 group were rising, the motor function of lower limbs of rats have also improved, the comparison of BBB scores in three groups at all time points : mi RNA group is highest, the second is BMSCs group and control group is lowest. The difference was statistically significant(P<0.05). 2. Three days after cell transplantation, comparison of NF200 positive cells number in all groups has no statistically significant(P>0.05). With the experimental progress, 1 week, 2 weeks, 4 weeks, 8 weeks after cell transplantation, NF200 staining positive cells number are increasing, the largest group is mi RNA group, BMSCs group followed, the least is control group, The difference was statistically significant(P<0.05) 3. The GFAP positive staining area of control group continues to increase. the comparison of GFAP positive staining area in three groups: control group is highest, the second is BMSCs group, the lowest is mi RNA group. The difference was statistically significant(P<0.05). 4. HE staining shows: three groups of rat spinal cord tissues are visible organization structure disorder, edema, pathological changes, such as nerve cells of mi RNA group and BMSCs group pathology change than those in control group.Conclusion1.Bone marrow mesenchymal stem cell can improve the movement of hind limbs of rats with spinal cord injury and the therapy of bone marrow mesenchymal stem cell modified mi RNA let- 7 b is better. 2. Bone marrow mesenchymal stem cells can differentiate into neurons in the microenvironment of spinal cord, and mi RNA let- 7 b can promote its differentiation. bone marrow mesenchymal stem cell transplantation can inhibit the formation of glial scar, and the function of bone marrow mesenchymal stem cell modified mi RNA let- 7 b is stronger 3. Bone marrow mesenchymal stem cell modified mi RNA let- 7 b can reduce the pathological changes of rats after spinal cord injury. |
PDF Full Text Request