Mitochondrial Determinants of Metabolic Disease in HIV-Infected Children

描述(申请人提供)：由于有效的抗逆转录病毒疗法，患有围产期获得性人类免疫缺陷病毒(HIV)感染的儿童现在可以很好地活到成年。这种疗法在延长生命方面的成功伴随着新出现的和进行性的长期并发症，包括代谢异常，如胰岛素抵抗、糖尿病和身体成分变化。该组织正在通过测量身体成分、青春期阶段、胰岛素抵抗和血脂异常的变化来评估营养、生长和新陈代谢。我们以前曾报道过在这一队列中胰岛素抵抗的高患病率。线粒体功能障碍，无论是由抗逆转录病毒治疗或慢性病毒感染引起的，已经被我们假设为HIV感染成人代谢功能障碍的一种机制。这项建议的目的是：1.比较PHACS中300名HIV(+)和100名HIV(-)儿童和HIV(+)儿童的线粒体功能[氧化磷酸化(OXPHOS)蛋白/酶活性和乳酸水平]，以确定与线粒体功能障碍相关的临床特征(代谢、年龄、性别、青春期、病毒载量、抗逆转录病毒治疗)；2.纵向超过4年，确定OXPHOS蛋白/酶活性的年变化、高乳酸血症的发生率和消退，以及这些变化的临床相关性；3.通过对HOMA-IR中胰岛素抵抗最高和最低的HIV感染儿童的每细胞线粒体DNA拷贝数、线粒体RNA转录本和线粒体氧化应激进行定量和比较，来描述线粒体功能障碍的机制。我们推测，抗逆转录病毒药物和HIV本身的线粒体毒性主要是由线粒体RNA和OXPHOS蛋白/酶活性水平的变化驱动的，这反过来又增加了线粒体反应氧应激和乳酸水平，导致胰岛素抵抗和脂肪营养不良。我们进一步假设，外周血单个核细胞(PBMC)或口腔细胞(颊拭子)中OXPHOS蛋白/酶活性的水平将与代谢性疾病的程度相关。如果这些假说得到证实，那么在理解儿童HIV/AIDS代谢异常的发病机制方面将具有重大的人类健康相关性。此外，PBMCs或口腔细胞的OXPHOS蛋白/酶活性可作为先发制人监测受试者线粒体代谢功能障碍风险的工具。

DESCRIPTION (provided by applicant): Children with perinatally-acquired Human Immunodeficiency Virus (HIV) infection are now living well into adulthood owing to effective antiretroviral regimens. The success of this therapy in prolonging life has been coupled with emerging and progressive longer-term complications, including metabolic abnormalities such as insulin resistance, diabetes mellitus, and body composition changes. The the effects of perinatally- acquired HIV infection as children age into adolescence and is evaluating nutrition, growth and metabolism by measuring changes in body composition, pubertal stage, insulin resistance, and dyslipidemia. We have previously reported a high prevalence of insulin resistance in this cohort. Mitochondrial dysfunction, either induced by antiretroviral therapy or chronic viral infection, has been a postulated by us as a mechanism for metabolic dysfunction in HIV infected adults. The objectives of this proposal are to 1. compare mitochondrial function [oxidative phosphorylation (OXPHOS) protein/enzyme activities and lactate levels] of 300 HIV (+) children and 100 HIV (-) in PHACS and among the HIV (+) children, to determine clinical characteristics (metabolic, age, sex, puberty, viral load, antiretroviral therapy) associated with mitochondrial dysfunction; 2. longitudinally over 4 years, to determine the annual change in OXPHOS protein/enzyme activities and the incidence and resolution of hyperlactemia, as well as the clinical correlates of these changes; and 3. delineate mechanisms of mitochondrial dysfunction by quantitating and comparing mitochondrial DNA copies per cell, mitochondrial RNA transcripts, and mitochondrial oxidative stress in the HIV-infected children with the highest versus the lowest tertile of insulin resistance as measured by HOMA-IR. We hypothesize that the mitochondrial toxicities of antiretroviral medications and HIV itself are driven primarily by alterations in mitochondrial RNA and OXPHOS protein/enzyme activity levels, which in turn increase mitochondrial reactive oxygen stress and lactate levels, resulting in insulin resistance and lipodystrophy. We further hypothesize that levels of OXPHOS proteins/enzyme activities in peripheral blood mononuclear cells (PBMCs) or buccal cells (cheek swabs) will correlate with the degree of the metabolic disease. Should these hypotheses be verified, there would be significant human health relevance in the understanding of the pathogenesis of metabolic abnormalities in pediatric HIV/AIDS. Additionally, PBMCs' or buccal cells' OXPHOS protein/enzyme activities may serve as tools to monitor subjects preemptively for risk of mitochondrial metabolic dysfunction.