Gut extracellular vesicles promote alcohol-induced liver injury via TLR4-regulated miRNAs

这个项目的首要主题是探索导致酒精性免疫调节的机制。 肝病（ALD）。我们将重点关注肠道和肝脏巨噬细胞的细胞外囊泡（EV）。具体地说， 我们将研究微生物抗原如何通过TLR 4信号刺激肠道EV的产生， 这些事件在通过肠-肝轴发展ALD中的后果。新的体外和体内方法 将用于解决行动机制问题，目的是确定新的干预目标。我们 提出肠源性EV调节肝脏巨噬细胞的积累和极化， 酒精诱导的慢性炎症通过TLR 4信号传导。我们特别提出，TLR 4激活 细胞外miRNA的产生是巨噬细胞活化的关键。基于我们发表的研究成果 和其他初步数据，该提案将测试微生物抗原调节生产的假设 通过TLR 4信号传导，启动巨噬细胞之间的串扰， 肝细胞ALD。此外，我们将确定饮食相关的纳米颗粒是否携带炎症 miRNAs抑制剂在ALD中具有潜在的治疗意义。这些假设将在下面进行检验 具体目的：目的1：确定TLR 4调节的肠道EV对酒精诱导的肝脏炎症的作用 和伤害。目的2：确定通过TLR 4调节IEC miRNAs的改变是否影响了 酒精诱导的肝脏炎症和损伤。在圆满完成上述工作后， 具体目的，我们的新研究将（i）验证TLR 4激活的EV与肝细胞活化直接相关， （ii）确定了TLR 4-细胞外miRNA轴在ALD小鼠模型中的预防潜力， ALD和（iii）为将来研究ALD中肠道EV和细胞外miRNA的机制提供了基础 疗法

The overarching theme of this project is to explore the mechanisms that lead to immune regulation of alcoholic liver disease (ALD). We will focus on extracellular vesicles (EVs) of gut and hepatic macrophages. Specifically, we will examine how microbial antigen stimulates the production of gut EVs through TLR4 signaling and the consequences of these events in the development of ALD via gut-liver axis. Novel in vitro and in vivo approaches will be used to address mechanisms of action with the goal of identifying new targets for intervention. We propose that gut-derived EVs regulate the accumulation and polarization of hepatic macrophages during alcohol-induced chronic inflammation via TLR4 signaling. We specifically propose that TLR4-activated extracelluar miRNAs production is the key to the activation of macrophages. Based on our published work and other preliminary data, this proposal will test the hypothesis that microbial antigen regulates the production of gut extracellular miRNAs through TLR4 signaling, which initiates a crosstalk among macrophages and hepatocytes in ALD. Moreover, we will determine whether diet-associated nanoparticles carrying inflammatory miRNAs inhibitor have potential therapeutic implications in ALD. These hypotheses will be tested in the following Specific Aims: Aim 1: Determine the role of TLR4-regulated gut EVs on alcohol-induced liver inflammation and injury. Aim 2: Determine whether alteration of IEC miRNAs via TLR4 modulation affects the severity of alcohol-induced liver inflammation and injury in ALD. Following the successful completion of the above Specific Aims, our novel studies will (i) validate TLR4 activated EVs is directly relevant to the activation of hepatic macrophages in ALD, (ii) define the preventive potential of TLR4-extracellular miRNAs axis in a mouse model of ALD and (iii) provide a foundation for future mechanistic investigation of gut EVs and extracellular miRNA in ALD therapy.