旁分泌调控内皮前体细胞Wnt信号通路促血管新生治疗糖尿病足微循环障碍

The oxidative stress and paracrine abnormality, cell dysfunction of endothelial progenitor cells (EPCs) in diabetic microenvironment will impair the pro-angiogenesis and regenerative repair effect of EPCs on diabetic foot microcirculation. Researchers have found out that paracrine can regulate Wnt/β-Catenin signaling pathway of stem cells and have important modulatory effect to the maintenance of stem cells. The activation of this signaling pathway can inhibit stem cells oxidative stress level. Our previous study found that reduce the oxidative stress level can restore diabetic EPCs function. As EPCs stand in an intermediate states of differentiation from stem cells to endothelial cells and also can paracrine multiple cytokines, we speculate that paracrine activation of Wnt/β-Catenin signaling pathway can produce similar anti-oxidative stress effect on EPCs as on stem cells, improving the EPCs function. This program plans to quantitatively analyze paracrine and oxidative stress status of EPCs under glucose burden gradients, high-throughputly screen the paracrine factor group relating to Wnt/β-Catenin pathway regulation in EPCs and its mechanism, interfere the paracrine of diabetic EPCs at gene transcription and mRNA translation level with the purpose of observing its modulation function on Wnt/β-Catenin pathway and verifying its pro-angiogenesis effect by animal experiment of treating diabetic foot microcirculatory disturbance.

内皮前体细胞（EPCs）在糖尿病微环境下氧化应激与旁分泌异常，细胞功能障碍，影响其促血管新生、再生修复糖尿病足微循环疗效。已有研究发现干细胞旁分泌能调控Wnt/β-Catenin信号通路，对干细胞的维持起重要调控作用，激活此信号通路可抑制干细胞氧化应激水平。我们前期研究发现抑制氧化应激水平能恢复糖尿病EPCs功能。由于EPCs处于干细胞向内皮细胞分化的中间态，且同样旁分泌多种细胞因子，我们推测旁分泌激活Wnt/β-Catenin通路可产生类似干细胞上的抗氧化应激效应，促进EPCs功能。本项目拟对糖负荷梯度下EPCs旁分泌/氧化应激进行定量与细胞功能分析；高通量分析与Wnt/β-Catenin通路调控相关EPCs旁分泌因子及作用机制；并在基因转录与mRNA翻译水平上干预糖尿病EPCs旁分泌，观察对Wnt/β-Catenin通路的调控作用，并通过动物实验验证促血管新生改善糖尿病足微循环的疗效。

本研究通过从小鼠骨髓分离提取EPC，研究了旁分泌因子FGF2对高糖诱导下的EPC功能和生物学活性的影响，发现加入外源性FGF2后，高糖下EPC的数量减少以及体外生物学活性及血管新生能力降低有显著改善。此外，我们还发现FGF2是通过激活Wnt/β-Catenin通路发挥作用的。体内试验也表明了FGF2则对受损EPC的功能具有修复作用。另外，我们的研究延伸到糖尿病引发的糖尿病肾病中的作用，研究了lnc MALAT1和miR-23c及其靶基因ELAVL1在肾小管上皮细胞中的作用及其可能分子机制。这些研究可能对开发治疗糖尿病足及其其他糖尿病并发症的新治疗策略具有重要意义。