Oxidative damage and proteasome activity: Role of opioid in HIV-HCV infection

描述（由申请人提供）：在注射吸毒者（IDUs）中，人类免疫缺陷病毒（HIV）和丙型肝炎病毒（HCV）是两种最常传播的血源性病原体。在美国，大约25%的HIV感染者同时感染丙型肝炎病毒（HCV），而在注射毒品感染HIV的人群中，HCV感染的发生率接近90%。尽管HCV在HIV疾病进展中的作用尚不清楚，但合并HIV感染与慢性丙型肝炎向肝硬化和终末期肝病的加速进展有关。在合并HIV-1感染的个体中，导致肝病更快进展和HCV病毒血症增加的机制尚不完全清楚。病毒感染迅速触发细胞内信号事件，导致先天细胞抗病毒状态，先天免疫的损伤可能为持续的病毒感染产生有利的微环境。大多数与HCV感染相关的肝损伤是由先天和获得性免疫反应介导的。吗啡是海洛因的主要代谢物，是最常见的阿片药物，可优先激活<-阿片样受体（MOR）。长期使用和滥用吗啡已被证明会损害宿主的先天免疫反应，包括趋化因子和促炎细胞因子的产生、吞噬和中性粒细胞迁移，这可能导致对细菌和病毒感染的易感性增加。吗啡通过下调IFN-1介导的先天免疫，促进HCV在肝细胞中的复制。趋化因子和促炎细胞因子是免疫反应和炎症过程的重要介质。更具体地说，促炎细胞因子肿瘤坏死因子-1 （TNF-1）在许多病理生理状态下，如毒素、缺血/再灌注和肝炎病毒引起的肝损伤，在肝细胞损伤和细胞死亡中起着不可或缺的作用。此外，吗啡诱导的氧化损伤被认为是造成肝脏疾病和肝毒性的许多系统性表现的原因，在小鼠和海洛因滥用者身上的实验显示。MOR的激活可以引发活性氧（ROS）的增加和细胞凋亡。利用最近建立的体外HCV感染系统，我们将验证阿片类药物通过1)增加细胞因子和趋化因子的产生和2)诱导反应性氧化物种（ROS）和一氧化氮（NO）破坏肝细胞对HCV和HIV的反应，从而促进HCV疾病进展的假设。公共卫生相关性：本提案的研究将侧重于分析阿片类药物和艾滋病毒在多大程度上增强人类肝细胞对HCV感染的易感性，特别是对促炎细胞因子肿瘤坏死因子- α (TNF-1)的易感性，我们将研究阿片类药物和艾滋病毒影响HCV感染肝细胞中病毒复制和毒性的机制。

DESCRIPTION (provided by applicant): Among injection drug users (IDUs), human immunodeficiency virus (HIV) and hepatitis C virus (HCV) are the two blood-borne pathogens most commonly transmitted. About 25% of HIV infected persons in the United States are also infected with Hepatitis C virus (HCV) while the incidence of HCV infection among persons who acquired HIV from injection drug use approaches 90%. Although the role of HCV in progression of HIV disease remains unclear, co-infection with HIV infection has been associated with accelerated progression of chronic hepatitis C towards cirrhosis and end stage liver disease. The mechanisms responsible for more rapid progression of hepatic disease and increased HCV viremia in individuals co-infected with HIV-1 are not fully understood. Viral infection rapidly triggers intracellular signaling events, leading to an innate cellular antiviral state, and damage to the innate immunity may generate a favorable microenvironment for persistent viral infection. Most liver damage associated with HCV infection is mediated by innate and acquired immune responses. Morphine, the major metabolite of heroin, is the most common opiate drug and preferentially activates <-opioid receptors (MOR). Chronic morphine use and abuse has been shown to impair host innate immune responses, including the production of chemokines and pro-inflammatory cytokines, phagocytosis, and neutrophil migration, which can lead to increased susceptibility to bacterial and viral infections. Morphine, through down- regulation of IFN-1 mediated innate immunity, favors HCV replication in hepatic cells. Chemokines and pro- inflammatory cytokines are important mediators of the immune response and the inflammatory process. More specifically, the pro-inflammatory cytokine, tumor necrosis factor-1 (TNF-1) plays an integral role in hepatocyte injury and cell death in a number of pathophysiological states such as liver injury from toxins, ischemia/ reperfusion, and hepatitis virus. In addition, morphine-induced oxidative damage has been hypothesized to contribute too many of the systemic manifestations of liver disease and hepatotoxicity experimentally shown in mice and in heroin abusers. Activation of MOR can trigger increased production of reactive oxygen species (ROS) and apoptosis. Using a recently established in vitro HCV infection system, we will test the hypothesis that opioids contributes to HCV disease progression by disrupting the response of hepatocytes to HCV and HIV through 1) increase production of cytokines and chemokines and 2) induction of reactive oxidative species(ROS) and nitric oxide (NO). PUBLIC HEALTH RELEVANCE: Studies in this proposal will focus on assaying the extent by which opioids and HIV enhances the susceptibility of HCV infection in human hepatocytes in particular, to proinflammatory cytokine tumor necrosis factor-alpha (TNF-1) and we will investigate the mechanisms by which opiates and HIV affect viral replication and toxicity in HCV infected hepatocytes.