Mechanisms of anti-inflammation and membrane stabilization in muscular dystrophy

 说明(申请人提供)：项目摘要/摘要：自20世纪50年代S以来，药理糖皮质激素一直是大多数炎症性疾病的标准治疗药物，并一直是全球最常用的处方药之一。它们在标签外用于治疗Duchenne(DMD)和部分肢体腰带(LGMD)肌营养不良症。尽管它们的疗效令人印象深刻，并得到了广泛的应用，但其复杂的作用机制尚未被剖析，而且严重的副作用是限制其用途并对患者生活质量产生负面影响的大问题。一种名为VBP15的新化合物在DMD的MDX小鼠模型中分离了疗效和副作用，目前正在进行DMD临床试验。这与小鼠受体通路中的关键突变一起，将有助于解决一个重要的、长期存在的问题：药理糖皮质激素的作用机制是什么，以及如何改进这一点？这项建议的目的是：1)确定配体对GR-磷酸化、降解和DNA相互作用的特定影响；2)确定GR是否在dystrophin缺乏症的病因和类固醇的疗效中起作用；3)发现膜稳定的作用机制(VBP15，Poloxamer-188)是否对营养不良的心脏健康产生目前治疗中没有发现的益处。这位名为Christopher Heier博士的博士是一名分子遗传学家，他在儿科神经肌肉疾病和翻译分子医学方面的背景非常适合推进本提案中的目标。在K99阶段，Heier博士将获得以下方面的新培训：1)下一代测序技术(CHIP-SEQ)，ii)活细胞成像(FRAP，即光漂白后的荧光恢复)，以及iii)活体动物成像(超声心动图)。海尔博士组建了一支强大的导师团队，他们在整个生物体和单个细胞的遗传学、动物模型、活细胞成像和组学方法方面都有专业知识(主要导师：Eric Hoffman博士，共同导师：Kanyboina Nagaraju，博士，DVM，Jyoti Jaiswal，博士)。拟议中的K99/R00应用程序是促进Heier博士过渡到独立职业生涯的最终目标的理想载体，该目标专注于开发治疗神经肌肉孤儿疾病的下一代疗法，通过共享分子生物学途径使更多的患者受益。

 DESCRIPTION (provided by applicant): Project Summary/Abstract: Pharmacological glucocorticoids have been the standard of care for most inflammatory disorders since the 1950's, and remain among the most prescribed drugs worldwide. They are used off-label to treat Duchenne (DMD) and a subset of limb-girdle (LGMD) muscular dystrophies. Despite impressive efficacy and widespread use, their complex mechanism of action has not been dissected, and harsh side effects are a large problem that limits their utility and negatively impacts patient quality of life. A new compound, VBP15, separates efficacy from side effects in the mdx mouse model of DMD, and is now moving towards DMD clinical trials. This, along with key mouse mutations in receptor pathways, will help to address an important, long-standing question: What is the mechanism of action of pharmacological glucocorticoids, and how can this be improved? The aims of this proposal are: 1) to determine ligand-specific effects on GR- phosphorylation, degradation and DNA interactions; 2) to determine if GR has a role in dystrophin-deficiency disease etiology, and in efficacy of steroids; and 3) to find if membrane-stabilizing mechanisms of action (VBP15, poloxamer-188) produce benefits to dystrophic heart health that are not found for current treatments. The PI, Dr. Christopher Heier, is a PhD molecular geneticist whose background in pediatric neuromuscular disorders and translational molecular medicine is uniquely suited to advance the aims in this proposal. During the K99 phase, Dr. Heier will obtain new training in: 1) next-generation sequencing technologies (ChIP-seq), ii) live-cell imaging (FRAP, or Fluorescence Recovery After Photobleaching), and iii) live-animal imaging (echocardiography). Dr. Heier has assembled a strong mentoring team with expertise in genetics, animal models, live-cell imaging, and -omics approaches to both whole organisms and single cells (Primary Mentor: Eric Hoffman, PhD, Co-mentors: Kanneboyina Nagaraju, PhD, DVM, Jyoti Jaiswal, PhD). The proposed K99/R00 application is the ideal vehicle to promote Dr. Heier's ultimate goal of transitioning to an independent career focused upon developing next- generation therapeutics for neuromuscular Orphan diseases, in a manner that benefits larger patient populations through shared molecular biology pathways.