以NMⅡ为靶点预处理的MSCs移植改善吸入性损伤疗效及机制研究

Stem cell apoptosis resulted from ischemia and hypoxia etc is a key factor that affacts its engraftment and survival in vivo, which affects therapeutic effect seriously.Therefore anti-apoptosis is focused in the field of stem cell research.Currently, various theories can not completely explain stem cell apoptosis mechanism, and corresponding regulation stategy is limited, which prompts us to further research on stem cells apoptosis and search for new interventional measure. Studies have demonstrated that non-myosin II (NMII) plays an important role in apoptosis of iPS cell. Inspired by that theory,in this study, we, on the basis of rat bone marrow-derived mesenchymal stem cells (MSCs) transplantation for therapy of smoke inhalation injury in the past, attempt to inhibit the NMII gene expression in MSCs by use of RNA interference technology (RNAi), and evaluate comprehensively the therapeutic effect of MSCs can't express NMII transplatation on smoke inhalation injury via investigation of MSCs morphology, cells engraftment and survival, vitaliity, expression of apoptosis-related protein, paracrine factors and self-renewal regulators, histopathological change in vivo and in vitro experiments.Meanwhile we would reveal initially the possible mechanism of stem cells that can't express NMII therapy for smoke inhalation injury via detection of Rho-ROCK signaling pathway with the aim of laying theoretical foundation of improvement of therapeutic effect and its mechanism.

缺血缺氧等因素导致的干细胞凋亡是影响其体内移植和存活的关键因素，严重影响其疗效。因此，抗凋亡是干细胞领域的研究热点。现有学说不能完全解释干细胞凋亡机制，相应调控手段十分有限，这促使我们继续深入研究干细胞凋亡机制并寻找新干预措施以改善其疗效。研究显示，非肌肉肌球蛋白II（NM II）在多能干细胞的凋亡和自我更新中发挥重要作用。受到启发，本研究在以往骨髓间充质干细胞（MSCs）移植成功治疗吸入性肺损伤的研究基础上，以NMⅡ为靶点，采用RNAi，抑制其在大鼠MSCs中的表达，通过体内体外实验考察MSCs形态学、移植率、生存率、活力、凋亡相关基因及蛋白、旁分泌因子、更新因子、组织病理的变化，综合评价RNAi 抑制MSCs中NM II基因表达后对其治疗烟雾吸入性损伤疗效的影响，并通过检测Rho-Rock 信号途径的变化，揭示其可能机制，为改善干细胞治疗吸入性损伤疗效及其机制奠定理论基础。

缺血缺氧等因素导致的干细胞凋亡是影响其体内移植和存活的关键因素，严重影响其疗效。因此，抗凋亡是干细胞领域的研究热点。现有学说不能完全解释干细胞凋亡机制，相应调控手段十分有限，这促使我们继续深入研究干细胞凋亡机制并寻找新干预措施以改善其疗效。研究显示，非肌肉肌球蛋白 II（NM II）在多能干细胞的凋亡和自我更新中发挥重要作用。受到启发，本研究在以往骨髓间充质干细胞（MSCs）移植成功治疗吸入性肺损伤的研究基础上，以 NMⅡ为靶点，采用 RNAi，抑制其在大鼠MSCs 中的表达，通过体内体外实验考察 MSCs 形态学、移植率、生存率、活力、凋亡相关基因及蛋白、旁分泌因子、更新因子、组织病理的变化，综合评价 RNAi 抑制 MSCs 中 NM II 基因表达后对其治疗烟雾吸入性损伤疗效的影响，并通过检测 Rho-Rock 信号途径的变化，揭示其可能机制，为改善干细胞治疗吸入性损伤疗效及其机制奠定理论基础。目前我们的结果显示，体外沉默NM II 基因不影响MSC的旁分泌能力。较单纯MSC治疗，沉默NM II 的MSC能显著改善吸入性损伤（血气分析、肺泡灌洗液中炎症因子、肺组织病理学改变等）。其机制和信号途径结果实验正在进行中。