Alcohol and Monocyte Signaling

 描述（由申请人提供）巨噬细胞（Macrophages，MMPs）、枯否细胞（Kupffer cell，KC）和中性粒细胞在酒精性肝病（ALD）的发病机制中介导炎症。先前的研究已经证明，促炎性巨噬细胞对酒精性肝脏炎症的破坏作用和肝脏中的高中性粒细胞浸润预测人类酒精性肝炎的不良结局。先前在人类中的报告和我们在小鼠中的初步数据表明，在慢性酒精摄入后，肝脏中存在经典活化的炎症M1和替代活化的M2巨噬细胞。然而，在ALD中，M1和M2型巨噬细胞（MIBs）极化或MIBs极化的治疗靶向的意义尚待探索。我们推测，M2极化不足允许慢性炎症和优先M1巨噬细胞表型在肝脏中。我们进一步假设，减少M2 MIPs极化是由于，至少部分是由于中性粒细胞的吞噬作用不足。我们推测，促进M2巨噬细胞极化的治疗干预将减弱酒精诱导的肝脏炎症和损伤。我们最近发现，细胞外膜极化microRNA也被包装在细胞外囊泡（EV）中，这些小的膜囊泡可以在细胞间通讯中充当信号细胞器。在我们的初步实验中，我们观察到在酒精性肝损伤的人和小鼠的循环中EV的数量增加。我们假设酒精诱导的EV是肝脏炎症和巨噬细胞极化的重要调节因子。基于这些观察，我们的目标是：具体目标#1：通过a）评价体内酒精诱导的细胞外囊泡（EV）对体外巨噬细胞极化的影响; B）测试体内酒精诱导的EV对体内肝脏中炎性细胞的募集和表型的影响; d）评估患有酒精性肝炎的人类患者中的循环EV，表征其miRNA组成和对单核细胞极化的影响。具体目标2：通过评估酒精对中性粒细胞的调节及其在酒精性肝炎患者体内和体外M1/M2巨噬细胞极化中的作用，研究ALD中巨噬细胞极化的触发因素。具体目标3：探讨调节MMP 3表型/极化的干预措施对小鼠酒精诱导的肝脏脂肪变性、炎症和肝损伤的治疗潜力。

 DESCRIPTION (provided by applicant) Macrophages (MØ), Kupffer cells (KC) and neutrophils mediate inflammation in the pathogenesis of alcoholic liver disease (ALD). Previous studies have demonstrated damaging effects of pro-inflammatory macrophages on alcoholic liver inflammation and high neutrophil infiltration in the liver predicted poor outcome in human alcoholic hepatitis. Prior reports in humans and our preliminary data in mice show that both classically activated inflammatory, M1, and alternatively activated, M2, macrophages are present in the liver after chronic alcohol intake. However, the significance of M1 and M2 type macrophage (MØ) polarization or therapeutic targeting of MØ polarization is yet to be explored in ALD. We hypothesize that insufficient M2 polarization permits chronic inflammation and preferential M1 macrophage phenotype in the liver. We further hypothesize that reduced M2 MØ polarization is due, at least partially, to insufficient phagocytosis of neutrophils. We postulate that therapeutic interventions that promote M2 macrophage polarization will attenuate alcohol- induced liver inflammation and injury. We recently found that MØ polarizing microRNAs are also packaged in extracellular vesicles (EVs), small membrane vesicles that could act as signaling organelles in cell-to-cell communication. In our preliminary experiments, we observed that the number of EVs is increased in the circulation of humans and mice with alcoholic liver injury. We hypothesize that alcohol-induced EVs are important regulators of inflammation and macrophage polarization in the liver. Based on these observations, our aims are: Specific Aim#1: To investigate the role of alcohol-induced extracellular vesicles (EVs) on macrophage activation and polarization by a) evaluating the effects of in vivo alcohol-induced EVs on macrophage polarization in vitro; b) testing the effect of in vivo alcohol-induced EVs on recruitment and phenotype of inflammatory cells in the liver in vivo; c) testing the effect of hepatocyte-derived EVs and their characteristic miRNAs on macrophage polarization in vitro; d) evaluating circulating EVs in human patients with alcoholic hepatitis, characterizing their miRNA composition and effect on monocyte polarization. Specific Aim#2: To investigate triggers of macrophage polarization in ALD by evaluating modulation of neutrophils by alcohol and their role in M1/M2 macrophage polarization in vitro and in vivo in patients with alcoholic hepatitis. Specific Aim#3: To explore the therapeutic potential of interventions that modulate MØ phenotype/polarization on alcohol-induced liver steatosis, inflammation and liver damage in mice.