Glycogen Synthase Kinase 3 beta in liver ischemia reperfusion injury

项目摘要 缺血再灌注损伤（IRI）是肝脏手术后的主要并发症。在肝移植中， 这是急性和慢性移植排斥的主要危险因素，限制了边缘供体的使用。肝 炎性免疫应答驱动IRI的发病机制。尽管在细胞和神经系统的研究方面取得了进展， 反应的分子机制，关于组织驻留的潜在独特作用的问题， vs.巨噬细胞浸润（iM），以及肝脏IRI的消退仍有待确定。 糖原合成酶激酶3β（Glycogen synthase kinase 3β，Gsk 3 β）是一种独特的信号激酶， 和抗炎基因程序在先天性刺激后的M细胞。它已经在小鼠肝脏中被证明 WT宿主中的Gsk 3抑制剂和髓样Gsk 3 β缺陷均保护肝脏的部分热缺血模型 通过AMPK-IL-10依赖性机制从IRI中获得。AMPK在肝缺血中的临床相关性 最近在肝肿瘤切除术中有记录。该提议的初步实验发现， Gsk 3 β还调节肝脏IRI的消退。事实上，Gsk 3 β调节肝脏炎症免疫激活 并通过靶向不同的肝M细胞群体来解决。KCs耗竭降低了肝脏保护性 然而，在骨髓Gsk 3 β KO小鼠中，肝脏IRI的恢复仍然加速。 这些KC缺失的KO宿主，表明Gsk 3 β在解决组织炎症方面调节iMФ。电流 本研究将详细分析Gsk 3 β在肝脏IRI不同阶段对这两种类型M β的调控机制。 IR诱导的肝脏炎性免疫激活以M β s的浸润和激活为特征 从外周（iM细胞），以及坏死性耗竭和组织驻留的促炎性转化 KC在肝脏炎症消退过程中，M β细胞通过免疫球蛋白修复肝细胞损伤并清除浸润的中性粒细胞。 Tyro 3-Axl-MerTK（TAM）受体酪氨酸激酶（RTK）介导的红细胞增多症。巨噬细胞坏死性凋亡和 巨噬细胞有力地调节它们的活化和分化。GSK 3 β促进应激诱导的细胞死亡 并调节巨噬细胞中TAM的表达。该提案将检验Gsk 3 β调节KC的假设 通过AMPK的坏死性凋亡和通过Mer RTK的促炎性免疫激活;和Gsk 3 β 抑制/失活通过以下方式促进iM β从促炎型转化为修复型： 增强Axl介导的红细胞增多和免疫调节信号传导。 两个具体的目的是为了解决Gsk 3 β如何调节KC炎症激活，和iM β如何调节KC炎症激活。 重编程/功能，分别在肝脏IRI的激活和消退阶段。结果进行 实验将提供新的见解GSK 3 β的免疫调节功能的M细胞在这两个方面， 激活和解决肝脏炎症和损伤，并为新的治疗方法提供理论基础。 恢复患者肝脏稳态的策略。

Project Summary Ischemia reperfusion injury (IRI) is a major complication after liver surgery. In liver transplantation, it is a major risk factor for both acute and chronic graft rejection and restrains the use of marginal donors. Liver inflammatory immune response drives the pathogenesis of IRI. Despite the progress in studies of cellular and molecular mechanisms of the response, questions regarding to the potential distinctive roles of tissue resident vs. infiltration macrophages (iMФs), and the resolution of liver IRI remain to be defined. Glycogen synthase kinase 3β (Gsk3β) is a unique signaling kinase that it differentially regulates pro- and anti-inflammatory gene programs in MФs upon innate stimulations. It has been shown in a murine liver partial warm ischemia model that both Gsk3 inhibitors in WT hosts and myeloid Gsk3β deficiency protect livers from IRI via an AMPK- IL-10-dependent mechanism. The clinical relevance of AMPK in liver ischemia has been documented recently in hepatic tumor resection. Preliminary experiments of this proposal have found that Gsk3β also regulates the resolution of liver IRI. In fact, Gsk3β regulates liver inflammatory immune activation and resolution by targeting distinctive populations of liver MФs. KCs depletion diminished the liver protective phenotype in myeloid Gsk3β KO mice against IR. However, the recovery of liver IRI remain accelerated in these KC-depleted KO hosts, indicating that Gsk3β regulates iMФs in resolving tissue inflammation. Current proposal will dissect mechanisms of Gsk3β regulation of these two types of MФs at different stages of liver IRI. IR-induced liver inflammatory immune activation is characterized by infiltration and activation of MФs from peripheral (iMՓs), as well as necroptotic depletion and pro-inflammatory conversion of tissue resident KCs. In liver inflammation resolution, MФs repair hepatocellular damage and clear infiltrated neutrophils via Tyro3-Axl-MerTK (TAM) receptor tyrosine kinase (RTK)-mediated efferocytosis. Macrophage necroptosis and efferocytosis potently regulate their activation and differentiation. Gsk3β promotes stress-induced cell death and regulates TAM expressions in MФs. The proposal will test the hypothesis that Gsk3β regulates KC necroptosis via AMPK and pro-inflammatory immune activation via Mer RTK; and Gsk3β inhibition/inactivation facilitates iMФ conversion from pro-inflammatory to reparative type by enhancing Axl-mediated efferocytosis and immune regulatory signaling. Two specific aims are designed to address how Gsk3β regulates KC inflammatory activation, and iMФ reprogramming/functions, in the activation and resolution stages of liver IRI, respectively. Results of these experiments shall offer fresh new insight into immune regulatory functions of Gsk3β in MФs in both the activation and resolution of liver inflammation and injuries and provide rationales for novel therapeutic strategies to restore liver homeostasis in patients.