Long-Term Safety, Efficacy, and Mechanism of PERK Inhibition Therapy for Prion Disease

项目摘要 背景 目前还没有可以阻止疾病中神经元退化过程的治疗方法。 与蛋白质错误折叠有关，如Pron病、阿尔茨海默病、帕金森病、 肌萎缩侧索硬化症(ALS)。最近的研究表明，激活剂是一种关键的 未折叠蛋白反应调节因子(UPR)，触发神经退行性变和 蛋白质错误折叠引起的神经炎症。GSK2606414，一种口服生物利用型福利 抑制剂，成功地延缓了小鼠传染性病毒病的进展超过3周 观察期，即使在症状出现后给药(9/9小鼠用 药物存活了普恩病毒感染，而未治疗的17只小鼠中有0只死亡)。然而，这种有希望的药物抑制了 胰腺β细胞和大脑中的PERK，因此会引起高血糖作为副作用。 虽然人类的高血糖可以很容易地控制，但要控制它要困难得多。 实验小鼠，因此试验不得不在三周后放弃。因此，我们 不知道抑制PERK是否能成功地在较长时间内治疗Pron病 时间以老鼠为单位。在计划对该药物进行人体临床试验之前，这些信息是至关重要的。 建议的实验 在特定目标1中，我们将使用表达他莫昔芬诱导的Cre重组酶的转基因小鼠 在Thy1启动子的控制下，在所有神经元中敲除PERK，但在胰腺β细胞中不表达。 不会发生高血糖，因此我们将能够完成PERK的延长试验 以前无法完成的抑制。我们将确定津贴的长期安全性 抑制率及其对小鼠病毒感染的治疗效果。这项研究将表明，反 PERK药物有可能被用作Pron疾病的长期治疗，并有可能作为 家族性Pron病患者的长期预防。我们的方法代表了一种成本- 以有效和省时的方式回答这些重要问题。在具体目标2中，我们将使用 带有PERK的转基因小鼠选择性地敲除星形胶质细胞和小胶质细胞以确定 PERK介导的神经炎症也参与了普恩病毒神经元死亡的机制 疾病。总而言之，我们的实验将提供有关安全性的重要信息， PERK抑制作为神经退行性变的长期疗法的有效性和机制。

Project Summary Background There are currently no therapies that can stop the process of neuronal degeneration in diseases associated with protein misfolding such as prion disease, Alzheimer's disease, Parkinson's disease, and Amyotrophic Lateral Sclerosis (ALS). Recent studies suggest that the kinase PERK, a critical regulator of the unfolded protein response (UPR), triggers both neurodegeneration and neuroinflammation in response to protein misfolding. GSK2606414, an orally bioavailable PERK inhibitor, successfully delayed the progression of infectious prion disease in mice over a 3-week observation period even when administered after the onset of symptoms (9/9 mice treated with the drug survived prion infection, while 0/17 untreated mice died). However, this promising drug inhibits PERK in pancreatic β-cells as well as the brain, and so causes hyperglycemia as a side effect. Although hyperglycemia can be easily managed in humans, it is much more difficult to control in experimental mice, and therefore the trial had to be abandoned after three weeks. Consequently we do not know whether inhibiting PERK could successfully treat prion disease for extended periods of time in mice. This information is critical before planning clinical trials of the drug in humans. Proposed Experiments In Specific Aim 1, we will use transgenic mice expressing tamoxifen-inducible CRE recombinase under the control of the Thy1 promoter to knock out PERK in all neurons, but not in pancreatic β-cells. Hyperglycemia will not occur, and therefore we will be able to complete the extended trial of PERK inhibition that could not be completed before. We will determine the long-term safety of PERK inhibition, and its efficacy in the treatment of prion infection in mice. This study will show whether anti- PERK drugs have potential for use as a long-term treatment for prion diseases, and potentially as long-term prophylaxis in individuals with familial prion disease. Our approach represents a cost- effective and time-efficient way to answer these important questions. In Specific Aim 2, we will use transgenic mice with PERK selectively knocked out of astrocytes and microglia to determine whether PERK-mediated neuroinflammation also contributes to the mechanism of neuronal death in prion disease. In summary, our experiments will provide important information about the safety, effectiveness, and mechanism of PERK inhibition as a long-term therapy against neurodegeneration.