Paracrine Signaling by Kupffer Cells in Hepatic Insulin Resistance

肝胰岛素抵抗中库普弗细胞的旁分泌信号传导

基本信息

批准号：
8888443
负责人：
MICHAEL P CZECH
金额：
$ 57.56万
依托单位：
UNIV OF MASSACHUSETTS MED SCH WORCESTER
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-03-09 至 2019-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8888443
关键词：
Address Affect Animal Model Attenuated CD14 Antigen CD14 gene CD36 gene Cell Lineage Cell Transplantation Cells Ceramides Cytokine Signaling Data Diabetes Mellitus Dissociation Educational process of instructing Encapsulated Endotoxins Experimental Models Fatty Acids Fatty Liver Fatty acid glycerol esters Functional disorder Gene Expression Gene Silencing Gene Targeting Genes Glucans Glucose Intolerance Goals Hepatic Hepatocyte Human Immune Immunologic Receptors Inflammation Inflammatory Insulin Insulin Resistance Interleukin-1 Knowledge Kupffer Cells Lead Left Lipids Liver Liver diseases MAPK8 gene Mediating Mediator of activation protein Metabolic Metabolic Diseases Metabolism Methods Molecular Mus Myeloid Cells Non-Insulin-Dependent Diabetes Mellitus Obese Mice Obesity Organ Paracrine Communication Pathology Pathway interactions Peptides Population Proteins Proteomics Research Rodent Role Signal Transduction Small Interfering RNA TLR4 gene TNF gene Technology Testing Tissues Transgenic Mice Triglycerides cytokine deep sequencing design glucose metabolism glucose output glucose tolerance in vivo insight insulin sensitivity insulin signaling insulin tolerance liver inflammation macrophage mouse model new technology novel nutrition p65 paracrine public health relevance receptor release factor response scavenger receptor sensor uptake

项目摘要

DESCRIPTION (provided by applicant): The overall long term goal of this project is to understand the mechanisms that generate fatty liver and hepatic insulin resistance in obesity, and the molecular relationships between these two phenomena. We seek to unravel the paradox whereby hepatic steatosis is tightly correlated with insulin resistance in humans, whereas these pathways can be clearly dissociated in experimental models. We hypothesize that this paradox may be solved by investigating Kupffer cells as mediators of insulin resistance in neighboring hepatocytes through their release of inflammatory cytokines in response to innate immune receptors and lipid sensors CD36 and Msr1 scavenger receptor. New evidence that these lipid sensors activate inflammasome and NFkB pathways in Kupffer cells provides a plausible mechanism whereby over-nutrition in obesity can lead to activation of liver inflammation. In order to attack this problem, we developed a unique glucan encapsulated siRNA (GeRP) delivery method to silence genes selectively in macrophages and Kupffer cells that reside specifically in liver, while leaving hepatocytes and macrophages in other tissues unaffected. With this method we can selectively probe Kupffer cell contributions to hepatocyte function in vivo in various mouse models of obesity. Using this approach we shall selectively silence Kupffer cell NFkB p65, Nlrp3, TLR4 co-receptor CD14, CD36 and Msr1 and other targets, alone and in combinations, to disrupt release of inflammatory factors in vivo. Metabolic profiling will be performed on these mice (glucose tolerance, insulin tolerance, systemic insulin sensitivity, hepatic glucose output and other metabolic parameters) to assess systemic effects of silencing Kupffer cell inflammation. We will then test the hypothesis that Kupffer cell factors that modulate whole body metabolism do so by paracrine signaling to neighboring hepatocytes. We also seek to discover novel Kupffer cell factors that disrupt hepatic insulin sensitivity using deep sequencing, proteomics and lipidomics approaches. Finally, we shall identify which intracellular pathways within hepatocytes cause impaired hepatocyte insulin signaling in response to Kupffer cell factors. Candidates such as DAG, ceramides, JNK as well as novel signaling components found in unbiased screens will be evaluated following GeRP-mediated silencing of inflammatory pathways in Kupffer cells in vivo.

描述（由适用提供）：该项目的总体长期目标是了解肥胖中产生脂肪肝和肝胰岛素抵抗的机制，以及这两种现象之间的分子关系。我们试图揭开悖论，从而与人类的胰岛素耐药性密切相关，而这些途径可以在实验模型中明确分离。我们假设可以通过研究库普弗细胞作为炎症受体受体和脂质传感器CD36和MSR1清除剂受体来解决邻近肝细胞中胰岛素抵抗的介质来解决该悖论。这些脂质传感器在库普弗细胞中激活炎症体和NFKB途径的新证据提供了一种合理的机制，从而使肥胖过度良好可导致肝脏注射的激活。为了攻击这个问题，我们开发了一种独特的葡聚糖封装的siRNA（GERP）递送方法，以在巨噬细胞和库普弗细胞中有选择地硅基因，该基因专门存在于肝脏中，同时在其他时候留下肝细胞和巨噬细胞。通过这种方法，我们可以在各种肥胖的小鼠模型中选择性地探测kupffer细胞对肝细胞功能的贡献。使用这种方法，我们将选择性地沉默kupffer细胞NFKB p65，NLRP3，TLR4共受体CD14，CD36和MSR1以及单独和组合中的其他靶标，以破坏体内炎症因子的释放。将对这些小鼠（葡萄糖耐受性，胰岛素耐受性，全身性胰岛素敏感性，肝葡萄糖输出和其他代谢参数）进行代谢分析，以评估沉默的Kupffer细胞注射的系统性效应。然后，我们将检验以下假设：调节全身代谢的库普弗细胞因子是通过旁分泌信号传导对相邻肝细胞的。我们还试图发现新型的kupffer细胞因子，这些因子使用深层测序，蛋白质组学和脂肪组学方法破坏肝胰岛素敏感性。最后，我们将确定肝细胞内哪些细胞内途径会导致肝细胞胰岛素信号受损，以响应kupffer细胞因子。在库普弗细胞中GERP介导的炎症途径沉默之后，将评估诸如DAG，Ceramides，JNK以及在无偏屏幕中发现的新型信号成分之类的候选人。