基于“气为血帅”理论从氧化应激角度探讨补阳还五汤治疗糖尿病周围神经病变的作用机制及黄芪最佳用量

Diabetic peripheral neuropathy (DPN) is one of the common complications of diabetes mellitus. Oxidative stress induced by superoxides in mitochondria is the main mechanism of DPN. Traditional Chinese medicine believes that qi deficiency causes blood stasis obstructing the collaterals. This is the pathogenesis of DPN. We use Buyang huanwu decoction to treat DPN, which can invigorate qi and promote blood circulation for removing obstruction in collaterals. The application of the large dosage of astragalus in Buyang Huanwu decoction is the specific clinical practice of the basic theory of " qi serves as the commander of the blood ", the purpose of which is to have sufficient qi to promote blood circulation and eliminate stasis. In previous studies, we found that Buyang Huanwu decoction of different astragalus doses could increase the antioxidant enzyme content in the peripheral nerves and reduce the oxidative stress response. This project intends to observe the effect of Buyang Huanwu Decoction with different doses of astragalus on the antioxidant enzyme Nrf2 / ARE regulatory pathway and mitochondrial function in dorsal root ganglion of DPN rats, clarify the way of Buyang Huanwu Decoction to play neuroprotection role and the optimal dose of astragalus, explore the significance of " qi serves as the commander of the blood " theory in the treatment of DPN, in order to guide the clinical and scientific research.

糖尿病周围神经病变是糖尿病常见的并发症之一。线粒体超氧化物产生过多引发氧化应激反应是导致DPN的主要机制。中医认为本病主要为络气虚滞，瘀血阻络，予以补气活血通络的补阳还五汤治疗。方中重用黄芪是 “气为血帅”中医基础理论的具体临床应用，其目的是令气旺血行而瘀去络通。我们在以往研究中发现不同黄芪剂量的补阳还五汤可增加周围神经中抗氧化酶含量，减轻氧化应激反应。本项目拟观察不同黄芪剂量补阳还五汤对DPN大鼠背根神经节Nrf2/ARE抗氧化酶调节通路和线粒体功能的调节作用，明确该方发挥神经保护作用的途径及方中黄芪的最佳剂量，探讨“气为血帅”理论在糖尿病周围神经病变治疗中的意义，指导临床及科研用药。

糖尿病周围神经病变（DPN）是糖尿病常见的并发症之一。氧化应激而致背根神经节神经元线粒体依赖性凋亡是DPN发生的主要机制。中医认为本病主要为络气虚滞，瘀血阻络，临床予以补气活血通络的补阳还五汤治疗取得了较好疗效。方中重用黄芪是 “气为血帅”中医基础理论的具体临床应用，其目的是令气旺血行而瘀去络通。但临床应用此方治疗DPN时，黄芪的用量并不统一。本研究用链脲佐菌素腹腔注射结合高糖高脂饲料诱导糖尿病，建立DPN大鼠模型，同时使用含有不同黄芪剂量（30g、60g、120g）补阳还五汤进行干预，以氧化应激和线粒体依赖性细胞凋亡为中心，对DPN大鼠周围神经感觉功能、线粒体质量、细胞凋亡、AMPK/Nrf2和AMPK/SIRT1/p53通路的各关键蛋白进行检测，揭示补阳还五汤作用途径和“气为血帅”中医理论的内涵，以及方中黄芪的最佳用量。实验结果证明了氧化应激导致的背根神经节线粒体结构受损，呼吸链复合物活性降低和膜电位下降是DPN气虚血瘀的病理基础。补阳还五汤通过调节AMPK水平，分别作用于Nrf2通路SIRT1/p53通路，减轻氧化应激，提高线粒体质量，保护神经功能，减少线粒体依赖性细胞凋亡，对DPN有治疗作用。其治疗作用与方中黄芪的用量有一定关系，120g黄芪用量的补阳还五汤的神经保护作用较60g和30g黄芪剂量补阳还五汤更明显。本项目从调节氧化应激、改善线粒体功能、减少线粒体依赖的细胞凋亡角度阐释了“气为血帅” 在 DPN 治疗中的微观意义。