牛膝多肽对周围神经损伤中施万细胞的保护及作用研究

The production of ROS following peripheral nerve injury can induce inflammatory response, which results to the cellular apoptosis. At meantime, it is able to trigger the neural regeneration. So, studies on how to control the ROS production and how to protect the neural cells from apoptosis mediated by inflammatory cytokines become the spotlight in the repair of injured nerves. Our previous research found that the Traditional Chinese Medicine active ingredients, Achyranthes Bidentata Polypeptides (ABPP) had the protective effects on the morphology and function after peripheral nerve injury. ABPP could prevent the loss of neurons in the peroneal nerve transection effectively, and induced the ROS production of Schwann cell, as well as protected the cell against apoptosis in response to the TNF-α challenge, but the related mechanisms are not clear. For further address the questions above, we are going to establish the ABPP protective model against TNF-α intervention, in attempt to clarify the protective function of ABPP against the Schwann cell apoptosis mediated by TNF-α; we also try to reveal the molecular signaling as to ABPP attenuating the Schwann cell apoptosis induced by TNF-α, expecting to unveil the target cells and target molecules of ABPP action; we will take insight to the function and molecular mechanism of ABPP regarding to the induction of ROS production in the Schwann cell; at last, we are going to uncover the regenerative effects by intervention of key regulators in the injured nerves. With the researches of ABPP on inducing the ROS production of Schwann cell, and on protective effects on the apoptosis mediated by inflammation, we will provide the beneficial data for application of the Traditional Chinese Medicine active ingredients.

周围神经损伤后的反应分子ROS既可以诱导炎症产生，促进细胞凋亡，但也能激发神经的再生。如何既控制ROS产生，同时对炎症因子介导的细胞凋亡又有保护作用，成为神经损伤修复的研究热点。在自主研发的中药有效成分牛膝多肽（ABPP）对外周神经损伤后形态和功能保护的研究基础上，我们发现ABPP能有效防止腓总神经横断后神经元的丢失，诱导施万细胞ROS的产生，同时却对炎症因子TNF-α介导的细胞凋亡有保护作用，但机制尚不清楚。本课题拟建立ABPP保护TNF-α干预的损伤模型，阐明ABPP对TNF-α诱发的凋亡保护作用；体外模型揭示ABPP消减TNF-α引发施万细胞凋亡的分子机制，寻找ABPP保护损伤神经的作用细胞和分子靶点；明确ABPP对施万细胞ROS产生的信号机制以及功能；在体干预关键靶分子，阐明其对损伤神经的影响。通过ABPP对施万细胞ROS的产生和炎症保护机理研究，为中药有效成分的应用提供理论基础。

从传统中药牛膝水提物中分离的牛膝多肽（ABPP），具有促进损伤周围神经再生等功能，但是其作用的细胞学基础和分子机制至今尚未阐明。这不但限制了该中药的临床效果评价，也不利于有效成分的鉴别纯化。课题组以大鼠坐骨神经损伤为模型，研究了ABPP对炎症因子诱导坐骨神经凋亡的保护作用、对胶质细胞施万细胞的增殖、迁移的分子机制和促进血管新生的信号通路，系统阐明了ABPP调控周围神经再生的组织细胞学基础及其关键分子靶点。通过建立TNF-α干预的周围神经损伤模型，采用不同浓度的ABPP处理，结果表明，一定浓度的ABPP通过促进施万细胞的存活，抑制TNF-α诱导的神经凋亡；ABPP处理原代培养的施万细胞检测发现，ABPP增加RIP与TRADD的相互作用，抑制FADD与TRADD的相互作用，逆转因TNF-α诱导引起的cIAP1、cIAP2 抗凋亡蛋白的表达下降；ABPP可以促进施万细胞中NOX4和DUOX2的表达，诱导ROS的产生，促进施万细胞的增殖和迁移，调控损伤神经的再生；ABPP通过上调血管内皮细胞中的SH2D3C表达，增加内皮细胞血管化，促进周围神经血管新生，从而有利于损伤神经的功能恢复。上述结果为传统中药牛膝的临床应用提供了重要的理论依据。