基于Cdk5/p25信号通路探讨hUC-MSCs微囊泡移植治疗缺血性中风及肾脑复元汤的干预调节研究

In recent years, neural regeneration in adult brain has been identified. With self-renewal and multi-lineage differentiation potential, human umbilical cord mensenchymal stem cells (hUC-MSCs) have drawn great public attention in scientific research; On the other hand, transplantation of MSCs may induce tumor in human body. In this research, we try to find a therapeutic strategy to remain the efficacy of MSCs while refraining from the risks. Microvesicles (MVs) are secreted by MSCs, transplatation of microvesicles remains the efficacy of tissue repairing and won’t lead to any risks, and the biological effects of MVs have been confirmed. .In the theory of TCM, kidney is the basis of human body and the therapeutic key of encephalopathy, curing the kideny could treat the cerebropathy. In this research,the theory of curing the kideny for the pathogenicity of brain and treating the kidney and brain at the same time is proposed.We use Kidney -Brain Recovering Decoction therapy and transplant the microvesicles of human umbilical cord mesenchymal stem cells(hUC-MSCs) to treat ischeamic stroke. At molecular and cellular level from zoopery and cellular experiments,we try to explain the specific mechanisms of this therapy by studying the neuranagenesis, secretion of neurotrophic factors, promotion of angiogenesis,prevention of apoptosis and oxidative stress, regulation and control of Cdk5/p25 signal path.In conclusion,we are trying to explain the signal transmission of cell apoptosis after cerebral ischemia, discovger a new treatment for ischemic stroke,and provide the evidence of treating neuropathy by combination of TCM and MVs of hUC-MSCs.

现已发现成人脑中存在神经再生，具有自我更新、多向分化潜能的人脐带间充质干细胞(hUC-MSCs)引起了科研界广泛关注；但MSCs移植也存在诱生肿瘤等问题，本课题旨在寻求一种既保全MSCs组织修复的功能、又不产生干细胞移植风险的治疗策略。微囊泡产生于MSCs，保留了MSCs的功能，又不存在移植风险，其生物学效应已得到证实。 .中医学认为肾为一身之本，髓海有病、其本在肾，治肾亦即治脑。本课题提出从肾治脑、肾脑同治理论，采用移植hUC-MSCs微囊泡治疗缺血性中风并联合中药肾脑复元汤干预，从细胞及动物学两个层面，从神经细胞再生、神经营养因子的合成、促血管新生、抗细胞凋亡、抗氧化应激及调控Cdk5/p25信号转导通路方面，探讨其抗脑缺血损伤的分子细胞学机制，并揭示脑缺血后神经凋亡的具体信号传递机制，为本病提供一种新的治疗思路，并为中医药联合hUC-MSCs 微囊泡移植治疗神经系统疾病提供实验依据。

缺血性脑卒中发病率高、死亡率高、致残率高，探索有效的治疗方案具有重要意义。中医学认为肾为一身之本，髓海有病、其本在肾，治肾亦即治脑。本课题提出从肾治脑、肾脑同治理论，采用移植hUC-MSCs或其微囊泡治疗缺血性中风并联合中药肾脑复元汤干预，从细胞学及动物学两个层面，从促神经细胞再生、神经营养因子合成、促血管新生、抗细胞凋亡及调控Cdk5/p25信号通路分子表达等方面，探讨其抗脑缺血损伤的分子细胞学机制。. 研究结果显示，肾脑复元汤能提高脑缺血再灌注大鼠神经营养因子HGF及TGF-β表达，降低凋亡因子cyt-C、Caspase-9、Caspase-3蛋白表达，下调CRH、CORT水平并上调海马GR水平，提高脑组织整合素α5β1表达，促进血管密度增加，减小梗死灶体积，改善脑缺血大鼠神经功能缺损状态。肾脑复元汤联合hUC-MSCs能够降低炎症因子TNF-α、IL-1β、IL-6及IL-10水平，减轻神经元凋亡，提高神经元活力，降低Cdk5及p25表达，升高p35表达，减轻脑组织病理形态学改变。肾脑复元汤联合hUC-MSCs微囊泡能够促进脑缺血再灌注后凋亡蛋白Bcl-2表达，抑制凋亡白Bax的表达，减轻脑组织细胞凋亡，改善脑组织病理学改变，改善大鼠神经功能缺损评程度。. 该研究证实了肾脑复元汤和/或hUC-MSCs及其微囊泡对脑缺血的神经血管保护作用，为探索中医学“肾脑同治”理论的物质基础提供了实验依据，完善了缺血性中风的中医病机认识，并为中医药治疗缺血性中风提供新思路。