去分化hUC-MSCs通过RARβ介导的hSDF-1α重编程机制参与HIBD神经修复

Human umbilical cord mesenchymal stem cells(hUC-MSCs) transplantation can promote neurological restoration in hypoxia-ischemia brain damage (HIBD), but it is an urgent problem to find suitable seed cells to improve the efficiency of transplantation and optimize the scheme of transplantation. In our previous work, we have found dedifferentiation hUC-MSCs (De-hUC-MSCs) transplantation can increase nearly 30%-40% of the treatment efficiency of HIBD rats. The result of microarray demonstrated reprogramming mechanism regulated the gene expression of De-hUC-MSCs, while hSDF-1 alpha was the most significant expressed gene as compared with hUC-MSCs, and in vivo experiment also verified the De-hUC-MSCs transplantation group had hSDF-1 alpha higher in brain tissue. At the same time, previous data also showed De-hUC-MSCs expressed RAR beta significantly. Therefore, we speculate that De-hUC-MSCs may participate in the recovery of HIBD by RAR beta mediating hSDF-1 alpha reprogramming expression. In this project, we are plan to carry out the in vivo and in vitro experiments to clarify the key effect of hSDF-1 alpha in De-hUC-MSCs transplantation for the treatment of HIBD, and through the in-depth research of the molecular mechanism of the regulation of hSDF-1 alpha, to lay the foundation for the advance treatment proposal.

hUC-MSCs移植可促进HIBD神经修复，但找寻适宜种子细胞优化移植方案、提高治疗效率，是目前亟待解决的问题。我们前期研究发现，去分化hUC-MSCs（De-hUC-MSCs）移植较hUC-MSCs移植可提高HIBD大鼠近30%-40%的治疗效率，芯片检测提示重编程机制调控De-hUC-MSCs基因表达，hSDF-1α是De-hUC-MSCs 较hUC-MSCs表达差异最大的基因，体内验证也发现De-hUC-MSCs组大鼠脑组织更高表达hSDF-1α，同时，我们前期还发现，De-hUC-MSCs差异高表达RARβ，因此推测De-hUC-MSCs可能通过RARβ介导hSDF-1α重编程表达促进HIBD神经修复。本项目拟开展体内外研究，阐明hSDF-1α在De-hUC-MSCs移植治疗HIBD中的关键作用，通过对调控产生hSDF-1α的分子机制进行深入研究，旨在为优化移植方案的提出奠定基础。

hUC-MSCs移植可促进HIBD神经修复，但找寻适宜种子细胞优化移植方案、提高治疗效率，是目前亟待解决的问题。本研究通过对hUC-MSCs进行神经分化、去分化及再分化诱导，将4种状态的细胞移植入HIBD大鼠体内，找寻最优种子细胞，通过体内外检测及验证，提出其发挥促神经修复作用机制。体外成功获得神经分化、去分化及再分化诱导细胞，通过全基因表达谱芯片检测，发现重编程机制可能参与hUC-MSCs神经分化、去分化及再分化过程，而去分化hUC-MSCs（De-hUC-MSCs）与hUC-MSCs生物学特性最接近，且具有最大的神经修复作用，而hSDF-1α是De-hUC-MSCs 较hUC-MSCs表达差异最大的基因，体内验证也发现De-hUC-MSCs组大鼠脑组织更高表达hSDF-1α，进一步构建sihSDF-1α及Ad-hSDF-1α病毒载体，正反向验证证明De-hUC-MSCs通过hSDF-1α促进HIBD神经修复，通过信号通路蛋白检测，发现De-hUC-MSCs可能通过CXCR4/PI3K/Akt信号通路调控hSDF-1α参与HIBD神经修复。通过本研究结果有望为临床优化移植治疗方案的提出奠定基础。