Erk-mTOR介导内皮细胞自噬在“虚毒瘀”致脓毒症心功能障碍的作用及益气活血解毒中药干预机制研究

The asthenia of healthy energy, tangle of toxin and blood stasis is the key pathogenesis of myocardial dysfunction in sepsis. Invigorating qi，strengthen body resistance, dissolve blood stasis and detoxicate is the key method of traditional chinese medicine.Our previous studies found that the traditional chinese medicine of this method, Tongguan Capsule could significantly improve myocardial dysfunction in rats and patients with sepsis.Nevertheless, the exact molecular mechanism remains unclear. Recent studies have demonstrated that the microcirculation disturbance induced by injuries of endothelial cell is the key eliology of multiple organ dysfunction syndrome caused by sepsis. Autophagy may play an important role in it. Our previous studies found that Tongguan Capsule protected against the damage of myocardial cell induced by ischemia/reperfusion injury through inducing the autophagy. Thus we speculate that Tongguan Capsule may improve myocardial dysfunction in sepsis by reducing the injuries of coronary endothelial cell, which was induced by autophagy. We will construct the model of myocardial dysfunction in sepsis, detect the effects of Tongguan Capsule on the autophagy of coronary endothelial cell and the Erk-mTOR pathway. The purpose of this study is to explore the traditional chinese medicial theory of myocardial dysfunction in sepsis. It will combinate the cardioprotective mechanism of invigorating qi，dissolve blood stasis and detoxicate method, and the improvement of microcirculation disturbance.The research is the first time to observe the role of autophagy of coronary endothelial cell in this process. The results may help to know the theory and explore new integrative Chinese and Western Medicine treatment in myocardial dysfunction of sepsis.

正气虚弱、毒瘀互结是脓毒症心功能障碍的关键病机，益气扶正、活血解毒是其关键治法。前期研究发现益气活血解毒中药通冠胶囊能明显改善脓毒症大鼠和患者的心功能障碍，但其机制尚不明确。新近研究证实，血管内皮细胞损伤致微循环障碍是脓毒症MODS的关键病因，自噬可能在其中发挥重要作用。前期研究发现通冠胶囊通过诱导自噬，减少缺血-再灌注心肌细胞的损伤。因此，我们推测通冠胶囊通过诱导自噬减少冠脉内皮细胞损伤，改善脓毒症心功能障碍。本研究拟从整体和细胞两个水平观察通冠胶囊对冠脉内皮细胞自噬体及Erk-mTOR通路的影响，探讨其脓毒症心脏保护机制。本研究立足发掘传统中医理论，将益气活血解毒法的脓毒症心脏保护机制与微循环障碍相联系，首次探讨内皮细胞自噬在其中发挥的关键作用；有助于从现代科学的微观指标诠释益气活血解毒法的实质内涵；为脓毒症心功能障碍中医临床基础理论的现代研究和中西医结合治疗找到切入点和开拓新的思路。

正气虚弱、毒瘀互结是脓毒症心功能障碍的关键病机，益气扶正、活血解毒是其关键治法。前期研究发现益气活血解毒中药通冠胶囊能明显改善脓毒症大鼠和患者的心功能障碍，但其机制尚不明确。本研究从整体和细胞两个水平观察通冠胶囊对冠脉内皮细胞自噬及Erk-mTOR通路的影响，探讨其脓毒症心脏保护机制。动物实验证明，脓毒症时伴随心功能障碍的发生，表现为心室扩张和射血分数的过度代偿，内皮细胞和心肌细胞损伤，自噬相关蛋白减少。通冠胶囊能改善脓毒症大鼠的心功能，能够减轻内皮细胞损伤和心肌细胞损伤。脓毒症心功能障碍大鼠，使用通冠胶囊后，自噬相关蛋白增加，其机制可能是通过促进ERK1/2通路发挥作用。在人冠脉内皮细胞实验中，使用小剂量内毒素（LPS）干预6h后，ET-1表达量减少，eNOS表达量增加，以及自噬小体增加，自噬相关蛋白增加。通冠胶囊含药血清干预后，能够逆转ET-1表达量的减少，逆转eNOS表达量的增加，自噬小体减少，自噬相关蛋白减少，其作用机制可能是抑制ERK1/2、p-ERK1/2的表达，轻度促进mTOR的表达，从而发挥抑制自噬的作用。目前国内外的研究证实，自噬对脓毒症的获益仍存在争议，在不同类型细胞中，自噬所发挥的作用也不尽相同。我们的研究证实内皮细胞中，LPS能够减少缩血管物质的产生，增加扩张血管的物质释放，自噬相关蛋白表达减少，而使用通冠胶囊后，这种变化得以逆转。通冠胶囊在改善内皮细胞功能方面有益，其机制可能是通过调控自噬来实现，而ERK1/2-mTOR可能是其靶向路径。但仍需更多的研究，明确这种逆转带来的宏观获益是脓毒症心功能障碍的主要机制之一。