Pannexin 1 channels in diet-induced metabolic syndrome

Pannexin 1 通道在饮食诱导的代谢综合征中的作用

基本信息

批准号：
10200124
负责人：
NORBERT LEITINGER
金额：
$ 40.58万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-08-01 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10200124
关键词：
Ablation Address Affect Age Aging Antisense Oligonucleotides Atherosclerosis Automobile Driving Blood Vessels CETP gene Cardiometabolic Disease Cardiovascular Diseases Caspase Cells Cellular Metabolic Process Cholesterol Cirrhosis Coculture Techniques Collaborations Data Diabetes Mellitus Diet Disease Disease Progression Elderly Fatty Liver Fibrosis Fructose Genetic Goals Health Hepatic Hepatic Stellate Cell Hepatocyte Hybrids Inbred Strains Mice Incidence Individual Inflammation Knowledge Life Style Liver Liver Fibrosis Liver diseases Mediating Metabolic Metabolic syndrome Metabolism Modality Modeling Molecular Mus Obesity Palmitates Pathologic Pathology Pattern Pharmacology Physiology Play Primary carcinoma of the liver cells Progressive Disease Property Resort Risk Risk Factors Role Signal Transduction Steatohepatitis Syndrome Testing Therapeutic Transgenic Mice Transgenic Organisms United States Virus age related atherosclerosis risk autocrine base blood glucose regulation blood lipid cardiometabolism cardiovascular effects cardiovascular risk factor combat coronary fibrosis extracellular gain of function humanized mouse liver transplantation mouse model mutant non-alcoholic fatty liver disease nonalcoholic steatohepatitis novel novel therapeutic intervention novel therapeutics overexpression paracrine patient subsets physical inactivity prevent stellate cell synergism western diet

项目摘要

PROJECT 3 PROJECT SUMMARY Lack of physical activity along with a western diet and lifestyle is accompanied by an increased incidence of obesity, diabetes, and fatty liver disease (NAFLD). NAFLD is considered an independent risk factor for cardiovascular disease and encompasses multiple progressive disease conditions beginning with hepatic steatosis, non-alcoholic steatohepatitis (NASH) and hepatic fibrosis, which is also associated with aging and increased risk for cirrhosis and hepatocellular carcinoma. The progression of NAFLD with accompanying hepatic fibrosis poses a significant health problem, culminating in liver transplant as the last resort. Treatment options are limited and there is a tremendous need for novel therapeutic concepts. The mechanisms driving NAFLD progression to fibrosis are largely unknown and may involve multiple insults by cell-derived danger- associated molecular patterns (DAMPs) such as extracellular ATP and its metabolites, which were implied to regulate hepatic inflammation and fibrosis. However, the mechanisms that control the release of ATP from hepatocytes are not known. Our preliminary data demonstrate that hepatocytes express functional pannexin-1 (Panx1) channels that release ATP upon lipotoxicity-induced caspase-dependent cleavage. Pharmacological inhibition or genetic deletion of Panx1 in hepatocytes protected mice against diet- and aging-induced steatosis, steatohepatitis and hepatic fibrosis. Based on these data, we will examine the hypothesis that Panx1- dependent ATP release from hepatocytes promotes fibrosis via activation of stellate cells and we will test if inhibition of Panx1 channel function is a feasible therapeutic approach to combat NASH. In specific Aim 1 we will investigate the effect of hepatic Panx1 deficiency (Panx1fl/fl/Albcre) and virus (AAV8)- mediated Panx1 ablation during the pathologically defined stages of fatty liver disease - steatosis, NASH, and advanced fibrosis, using mice fed a high fructose, palmitate, cholesterol (FPC) diet for 5, 12 or 16 weeks. Virus-mediated hepatic re-expression of Panx1 in Panx1-deficient mice and transgenic overexpression of Panx1 will be used as gain-of-function approaches. We will develop novel liver-specific antisense oligonucleotide (ASO)-mediated therapeutic approaches directed at Panx1, which will be tested in the FPC diet model, in transgenic APOE3- Leiden/CETP mice, a “humanized” mouse model of metabolic syndrome, and in aging-induced fibrosis. In specific Aim 2 we will test the hypotheses that (a) Panx1-dependent ATP release from hepatocytes regulates fibrotic capacity of hepatic stellate cells via paracrine effects, and (b) ATP or its metabolites controls metabolism of hepatocytes via Panx1-dependent autocrine mechanisms. Collectively, these data will provide us new information on diet-induced metabolic complications that are now considered predisposing and accelerating factors, part of the cardiometabolic syndrome; also, our new knowledge on liver fibrosis will also have implications for cardiac fibrosis.

项目 3 项目摘要缺乏体力活动以及西方饮食和生活方式会导致以下疾病的发生率增加：肥胖、糖尿病和脂肪肝病（NAFLD）被认为是独立的危险因素。心血管疾病，包括从肝脏开始的多种进行性疾病脂肪变性、非酒精性脂肪性肝炎 (NASH) 和肝纤维化，这也与衰老和衰老有关肝硬化和肝细胞癌的风险增加，并伴有 NAFLD 的进展。肝纤维化造成严重的健康问题，最终需要肝移植作为最后的治疗手段。选择是有限的，并且非常需要新的治疗概念的驱动机制。 NAFLD 进展为纤维化在很大程度上是未知的，并且可能涉及细胞衍生危险的多重损伤。相关分子模式 (DAMP)，例如细胞外 ATP 及其代谢物，这意味着调节肝脏炎症和纤维化然而，控制 ATP 释放的机制。我们的初步数据表明肝细胞表达功能性 pannexin-1。 (Panx1) 通道在脂毒性诱导的半胱天冬酶依赖性药理学裂解后释放 ATP。肝细胞中 Panx1 的抑制或基因缺失可以保护小鼠免受饮食和衰老引起的脂肪变性，根据这些数据，我们将检验 Panx1- 的假设。肝细胞依赖性 ATP 释放通过星状细胞的激活促进纤维化，我们将测试是否在特定目标 1 中，抑制 Panx1 通道功能是对抗 NASH 的可行治疗方法。将研究肝脏 Panx1 缺陷 (Panx1fl/fl/Albcre) 和病毒 (AAV8) 介导的 Panx1 的影响在脂肪肝疾病的病理定义阶段（脂肪变性、NASH 和晚期）期间进行消融纤维化，使用高果糖、棕榈酸酯、胆固醇 (FPC) 饮食喂养 5、12 或 16 周的病毒介导的小鼠。将使用 Panx1 缺陷小鼠的肝脏再表达 Panx1 和 Panx1 的转基因过表达作为功能获得方法，我们将开发新型肝脏特异性反义寡核苷酸（ASO）介导的方法。针对 Panx1 的治疗方法将在 FPC 饮食模型、转基因 APOE3 中进行测试 Leiden/CETP 小鼠，一种代谢综合征和衰老引起的纤维化的“人源化”小鼠模型。具体目标 2 我们将检验以下假设：(a) Panx1 依赖的肝细胞 ATP 释放调节通过旁分泌作用的肝星状细胞的纤维化能力，以及 (b) ATP 或其代谢物对照总的来说，这些数据将提供肝细胞通过 Panx1 依赖性自分泌机制的代谢。我们关于饮食引起的代谢并发症的新信息，这些并发症现在被认为是诱发和加速因素，心脏代谢综合征的一部分；此外，我们对肝纤维化的新认识也将对心脏纤维化有影响。