DDAH As a Novel Target in Pulmonary Fibrosis

描述(由申请者提供)：应聘者：我是一名代表性不足的科学家，提出了一个对NHLBI(肺脏研究)最感兴趣的研究领域。我对肺部疾病研究的浓厚兴趣源于我曾生活在一个与肺部相关的慢性疾病(如肺结核；与二手烟和二手烟以及与木材和木炭烟雾有关的疾病)流行的地区，因为人们的社会经济地位很差。因此，我目前得到了加州大学烟草相关疾病研究计划(TRDRP)的支持，在这一领域进行一项重要的研究。在此期间，我参与了一个项目，旨在对小分子进行高通量筛选(HTS)，以修饰二甲基精氨酸二甲氨基水解酶(DDAH)的酶活性；DDAH是一种通过调节一氧化氮合酶(NOS)途径参与心血管生理学的酶。我和我的导师库克博士一起勤奋地工作，设计了一种大规模生产重组DDAH的方法，并设计了一种进行HTS的检测方法。正如我们最近在《生物分子筛选》杂志上发表的文章中所描述的那样，我们的策略取得了成果，发现了几个调节DDAH酶活性的新型小分子。这对我来说尤其令人兴奋，因为DDAH已被证明主要参与肺损伤小鼠模型的肺纤维化进展，并被发现在特发性肺纤维化(IPF)患者的肺组织中上调。这两个重要环节：DDAH及其在IPF中的作用，以及发现调节DDAH活性的小分子，激发了我寻求恢复肺功能的新疗法的兴趣。环境：正如我在提案中所描述的，我的研究大大加快了速度，因为我的研究是在斯坦福大学进行的；斯坦福大学是一个一流的研究环境，拥有多个核心设施，用于药理学、分子和细胞研究。此外，斯坦福大学培养了多学科合作，并高度致力于将基础研究转化为临床有用的疗法。斯坦福大学这种从工作台到床边的翻译研究项目的两个例子是Spark和Bio-X Research项目。可能从这种翻译研究工作中受益的领域之一是IPF。在斯坦福大学，有一些小组正在积极致力于了解IPF的病理生物学和潜在疗法的开发。其中一个小组是我的共同导师，罗森博士的实验室，该实验室正在研究另一种治疗IPF的靶点。他们在这方面的专业知识对我的项目很有价值。此外，斯坦福大学还开设了几个相关的课程和研讨会，包括心肺研究进展、药物开发和未来学院，这些课程和研讨会对我的职业发展非常感兴趣。研究：IPF是一种侵袭性的不治之症，会逐渐破坏肺的正常结构。尽管IPF发生发展过程中的确切病因和事件顺序尚不完全清楚，但新的数据表明DDAH活性的失调可能在该病的发病机制中起关键作用。最近在博莱霉素诱导的IPF样肺损伤的动物模型中进行的机制研究表明，DDAH在疾病过程中起着中心作用。值得注意的是，用博莱霉素攻击的小鼠，用脱氢表雄酮抑制剂(L-291)治疗可以改善纤维化和恢复肺功能。此外，对人肺组织的分析表明，IPF中DDAH显著升高。因此，正如我的研究提案中所描述的那样，靶向这一途径可能具有一些治疗潜力。调节DDAH过度激活的一种方法是使用直接抑制其酶活性的小分子拮抗剂。因此，我们发现和验证了几种DDAH的小分子拮抗剂(包括FDA批准的(用于其他适应症))，值得进一步研究以用于治疗开发。职业目标：实际上，药物开发是一个漫长的过程(平均12年)，需要对疾病机制有基本的了解，并对药物进行优化，以选择性和有效地针对感兴趣的疾病。因此，我的近期目标是利用基于小分子的方法研究DDAH作为IPF药物靶点的可行性。如果这项研究的结果令人鼓舞，那么我将瞄准我的长期职业目标，通过形成一个合作网络来逐步优化药物先导，以合成和测试几个最有希望的化合物的类似物，并破译这种药物先导调节DDAH活性的机制。我计划继续药物发现和开发的道路，最终目标是进行临床试验，并开发一种治疗慢性肺部疾病的方法，特别是IPF。因此，NHLBI的这一研究科学家发展奖将为我提供一个无与伦比的机会来发展我的生物医学研究事业，并为科学界带来创新。拟议的研究是NHLBI主要感兴趣的领域，考虑到斯坦福的研究环境以及参与该项目的所有人员的奉献精神和专业知识，该研究是可行的。(摘要结束)

DESCRIPTION (provided by applicant): Candidate: I am an underrepresented scientist proposing an area of research that is of primary interest to the NHLBI (pulmonary research). My keen interest in pulmonary diseases research stems from having lived in an area where chronic lung-related diseases (such as tuberculosis; active- and secondhand- tobacco-smoke as well as wood- and charcoal- smoke related ailments) are endemic due to the poor socio-economic status of the people. As such, I am currently supported by the Tobacco-related Disease Research Program (TRDRP) of the University of California to pursue an important research in this area. During this fellowship, I worked on a project that aimed to conduct high throughput screen (HTS) of small molecules to modify the enzymatic activity of dimethylarginine dimethylaminohydrolase (DDAH); an enzyme involved in cardiovascular physiology by modulating the nitric oxide (NO) synthase (NOS) pathway. I worked diligently with my mentor, Dr Cooke, to design an approach for large-scale production of recombinant DDAH and an assay to conduct the HTS. As described in our recent publication in the journal of Biomolecular Screening, our strategy bear fruit by discovering several novel small molecules that regulate DDAH enzymatic activity. This was particularly very exciting to me as DDAH has been shown to be principally involved in the progression of pulmonary fibrosis in a murine model of lung injury and was found to be upregulated in lung tissues from idiopathic pulmonary fibrosis (IPF) patients. These two important links: DDAH and its role on IPF, and the discovery of small molecules to regulate DDAH activity, fueled my interest in pursuing the development of a novel therapy to restore lung function. Environment: As described in my proposal, my research is significantly accelerated due to it being conducted at Stanford; a superb research environment with multiple core facilities for pharmacological, molecular and cellular studies. In addition, Stanford nurtures multi-disciplinary collaborations and highly committed to translating basic research into clinically useful therapy. Two examples of such bench-to-bedside translational research programs at Stanford are the SPARK and the Bio-X Research Programs. One of the areas that may benefit from such translational research efforts is IPF. At Stanford, there are groups who are actively working towards understanding the pathobiology of IPF and the development of potential therapeutics. One of these groups is my co-mentor, Dr Rosen's, lab that is working on a different target to treat IPF. Their expertise in this area will be valuable i my project. Furthermore, Stanford offers several relevant courses and seminars including Cardiopulmonary Research-in-Progress; Drug Development, and Future Faculty which are of great interest for my career development. Research: IPF is an aggressive and incurable disease that progressively destroys the normal architecture of the lung. Although, the precise etiology and sequence of events in the development and progression of IPF remains incompletely characterized, emerging data indicates that dysregulation of DDAH activity might play crucial role in the pathogenesis of this disease. Recent mechanistic study in an animal model of bleomycin- induced IPF-like lung injury, validated by lung tissues from IPF patients, indicates that DDAH is centrally involved in the disease process. Remarkably, treatment of bleomycin-challenged mice with DDAH inhibitor (L- 291) ameliorated fibrosis and restored lung function. Moreover, analyses of human lung tissue showed that DDAH was significantly elevated in IPF. Therefore, targeting this pathway might have some therapeutic potential as described in my research proposal. One way of regulating DDAH over-activation is by using small molecule antagonists that directly inhibit its enzymatic activity. Therefore, our discovery and validation o several small molecule antagonists of DDAH (including FDA approved ones (for other indication)), deserves further investigation for therapeutic development. Career goals: Practically, drug development is a lengthy process (12 years on average) that requires fundamental understanding of disease mechanisms and optimization of drug-leads to selectively and efficiently target the disease of interest. Therefore, my immediate-term goal is to study the feasibility of DDAH as a drug target in IPF using small molecule-based approach. If the outcome of this study is encouraging, I will then aim for my long-term career goals to conduct step-wise optimization of the drug-leads by forming a network of collaborations to synthesize and test several analogs of the most promising compounds and decipher the mechanism by which such drug-leads regulate DDAH activity. I plan to continue the drug discovery and development path with the ultimate goal of conducting clinical trials and developing a therapy for chronic pulmonary diseases in general and IPF in particular. Therefore, this Research Scientist Development Award from NHLBI will provide me an unparalleled opportunity to develop my career in Biomedical Research and bring innovation to the scientific community. The proposed research is in an area of primary interest to the NHLBI and is feasible given Stanford's research environment and the dedication and expertise of all the personnel tapped in this project. (End of Abstract)