Modulation of Sp1/Sp3 by HIV-1 Tat Contributes to oxidative stress in HIV-PAH

HIV-1 Tat 对 Sp1/Sp3 的调节有助于 HIV-PAH 的氧化应激

• 批准号: 8992878
• 负责人: ADELA COTA-GOMEZ
• 金额: $ 46.03万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-17 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8992878
• 关键词: 3-nitrotyrosine; Acetylation; Acetylesterase; Acute; Address; Alveolar Macrophages; Animal Model; Animals; Anti-Retroviral Agents; Apoptosis; Arteries; Binding Sites; Biological; Biological Assay; Blood; Cardiac; Cell Culture Techniques; Cells; Chronic; Chronic Disease; Clinical; Deacetylase; Deacetylation; Diagnosis; Disease; Elements; Endothelial Cells; Epidemiology; Exposure to; Family; General Population; Genetic Transcription; Glutathione; HIV; HIV Infections; HIV tat Protein; HIV therapy; HIV-1; Heart Diseases; Hematopoietic stem cells; Histone Deacetylase Inhibitor; Human; Immune; Immune System Diseases; Implant; In Vitro; Indium; Individual; Infection; Inflammation; Inflammatory Response; Injury; Interleukin-2; Irrigation; Knockout Mice; Lead; Lipid Peroxides; Liver; Lung; Lung diseases; Manganese; Manganese Superoxide Dismutase; Measures; Mitochondria; Modeling; Molecular; Morbidity - disease rate; Mus; Nucleotides; Oxidants; Oxidative Stress; Pathogenesis; Patients; Peripheral Blood Mononuclear Cell; Pharmaceutical Preparations; Physiological; Play; Predisposition; Proteins; Pulmonary Hypertension; Pulmonary vessels; Regulation; Reporting; Repression; Research; Resistance; Role; Source; Sp1 Transcription Factor; Sp3 Transcription Factor; Specimen; Superoxide Dismutase; Superoxides; T-Lymphocyte; Thymic Tissue; Time; Tissues; Transcriptional Regulation; Transferase; Trichostatin A; Vascular remodeling; Viral; Viral Proteins; Virus Diseases; abstracting; antiretroviral therapy; combinatorial; fetal; in vivo; indexing; inhibitor/antagonist; mortality; mouse model; normotensive; novel; promoter; public health relevance; pulmonary arterial hypertension; pulmonary artery endothelial cell; receptor; research study; response; small hairpin RNA; tat Protein; tool; transcription factor

 DESCRIPTION (provided by applicant): Since the introduction of the highly active antiretroviral combinatorial therapies for HIV (HAART) the pathogenesis of HIV infection is now more commonly a chronic, long-term infection that has dramatically changed the epidemiology of this disease. Long-term exposure to low levels of viral replication has unmasked susceptibilities to a number of cardiac and pulmonary diseases that are now more common causes of morbidity and mortality. For example, HIV-associated pulmonary arterial hypertension (HIV-PAH) PAH is approximately 25 times more prevalent among HIV infected individuals than in the general population. We have found that the HIV Tat protein promotes a number of pro-oxidative and pro-inflammatory responses that are not directly related to its function as a viral transcriptional regulator. For example, we and others have demonstrated that Tat induces oxidative stress via depletion of glutathione and alteration of manganese- dependent superoxide dismutase (MnSOD). In endothelial cells, the resultant increase in oxidants can promote a number of physiological responses such as inflammation, apoptosis and subsequent proliferation of apoptosis-resistant cells that can contribute to the occlusion of pulmonary vessels. Thus, we propose that Tat- induced oxidative stress has a central role in initiating the pathogenic cascade that ultimate leads to pulmonary vascular remodeling in HIV-PAH. In this application, we seek to examine the mechanisms whereby the HIV-1 Tat protein modulates sod2 expression thereby contributing to a state of oxidative stress. We have defined a Tat-sensitive Sp-responsive element (TSS) containing multiple binding sites for the oxidant sensitive Sp family of transcription factors in the regions of the sod2 promoter proximal (up to nucleotide -210) to the transcriptional start and have shown that Tat decreases the Sp1/Sp3 ratio on the TSS. Given that Sp3 has reduced transcriptional activity compared to Sp1 and an inhibitory domain that that represses transcription, this shift in occupancy of the promoter will result in alteration of sod2 transcription. Our hypothesis is that HIV-1 Tat dysregulates sod2 expression via modulation of Sp1 and Sp3 transcription factors and contributes to a state of oxidative stress during HIV infection. In order to address the hypothesis we have crafted a research plan that combines in vivo mouse models to examine the oxidative state in the lungs during HIV infection and in vitro mechanistic experiments to probe potential molecular mechanisms for how Tat alters the Sp1/Sp3 ratio on the sod2 promoter. Lastly we will leverage our current bank of bronchalveolar lavage (BAL) and blood biospecimens from HIV+ individuals with and without PAH to address whether in HIV-infected patients, to investigate oxidative stress in human biological specimens of HIV-PAH and to ask mechanistic questions regarding the modulation of sod2 in HIV infection.

 描述（由应用提供）：由于引入了HIV（HAART）高度活跃的抗逆转录病毒组合疗法（HAART）HIV感染的发病机理现在更常见的是一种长期的长期感染，已大大改变了这种疾病的流行病学。长期暴露于病毒复制水平的水平较低，对许多心脏和肺部疾病的敏感性均具有敏感性，这些心脏和肺部疾病现在是发病率和死亡率的更常见原因。例如，与一般人群相比，与HIV感染的个体相比，与HIV相关的肺动脉高压（HIV-PAH）PAH的普遍性大约是普通人群的25倍。我们发现，HIV TAT蛋白促进了许多促氧化和促炎反应，这些反应与其作为病毒转录调节剂的功能无直接相关。例如，我们和其他人已经证明，TAT通过谷胱甘肽的消耗和锰依赖性超氧化物歧化酶（MNSOD）的改变会诱导氧化应激。在内皮细胞中，氧化物的产生增加可以促进许多物理反应，例如炎症，凋亡和随后的抗凋亡耐药细胞的增殖，这些细胞可有助于肺动脉尿的闭塞。因此，我们建议TAT诱导的氧化应激在启动致病性级联反应中具有核心作用，该致病性级联反应最终导致HIV-PAH肺血管重塑。在此应用中，我们试图检查HIV-1 TAT蛋白调节SOD2表达的机制，从而导致氧化物应激状态。我们已经定义了一个对TAT敏感的SP响应元件（TSS），其中包含SOD2启动子近端区域中氧化剂敏感的SP转录因子的多个结合位点（核苷酸-210核苷酸-210），并表明TAT降低了SP1/SP3降低Sp1/Sp3率。鉴于SP3与SP1相比和反映转录的抑制域的转录活性降低，因此启动子占用者的这种转移将导致SOD2转录的改变。我们的假设是，HIV-1 TAT通过调节SP1和SP3转录因子的SOD2表达失调，并在HIV感染过程中有助于氧化应激状态。为了解决该假设，我们制定了一项研究计划，该计划结合了体内小鼠模型，以检查HIV感染期间肺中的氧化态和体外机械实验，以探测TAT在SOD2启动子上如何改变SP1/SP3比的潜在分子机制。最后，我们将利用当前的支气管肺泡灌洗库（BAL）和来自有或没有PAH的HIV+个体的血液生物测量来解决HIV-PAH的HIV-PAH人类生物学规范中的氧化物应激，并询问有关HIV感染中SOD2调节的机械问题。