Prokineticin 2 and Neuroinflammatory Mechanisms

描述(申请人提供)：神经炎现在被认为是包括帕金森病(PD)在内的几种神经退行性疾病的关键退行性机制。神经炎性应激引起的神经元损伤的严重程度取决于脑内炎症和抗炎通路的失调程度。到目前为止，大多数研究都集中在识别在神经炎性损伤过程中被激活的主要促炎通路。了解与脑部炎症不同阶段相关的抗炎机制将为了解与神经退行性疾病相关的疾病过程提供新的见解。在这项提议中，我们的目标是在黑质纹状体多巴胺能神经元中描述一种新的抗炎保护反应，这种反应是由最近发现的曼巴蛇毒的哺乳动物蛋白同源物：原激动素-2(PK2)介导的。出乎意料的是，在炎症性肿瘤坏死因子损伤期间，我们观察到PK2蛋白的戏剧性上调及其从多巴胺能神经元细胞中的释放。进一步观察帕金森病动物模型黑质多巴胺能神经元以及死后帕金森病患者的黑质标本中PK2表达的增加，为我们的研究结果的临床意义提供了证据。有趣的是，重组PK2对神经炎性损伤诱导的神经细胞凋亡性死亡和TH阳性多巴胺能神经元丢失具有显著的保护作用。令人惊讶的是，PK2治疗还促进了星形胶质细胞和小胶质细胞的迁移。因此，在这项建议中，我们打算通过以下具体目标来扩展我们的初步观察：(I)在原代细胞培养和动物模型中表征炎症损伤后多巴胺能神经元中PK2的诱导、释放和功能，(Ii)确定PK2诱导对炎症刺激后星形胶质细胞和小胶质细胞迁移和功能的影响，(Iii)研究PK2上调神经细胞表达的分子机制，以及(Iv)在原代细胞培养和帕金森病动物模型中证明PK2的神经保护作用。将使用细胞、分子和神经化学方法来描述这些特定的目标。总之，了解PK2在炎症应激过程中在多巴胺能神经元中的上调和释放的作用，不仅将为黑质多巴胺能神经元退行性变的机制提供新的见解，还可能为帕金森病的治疗提供新的治疗策略。

DESCRIPTION (provided by applicant): Neuroinflammation is now recognized as a key degenerative mechanism in several neurodegenerative diseases including Parkinson's disease (PD). The severity of neuronal damage caused by neuroinflammatory stress is dependent on the degree of dysregulation of inflammatory and anti-inflammatory pathways in brain. Most studies to date are focused on identifying major pro-inflammatory pathways that are activated during neuroinflammatory insult. Understanding the anti-inflammatory mechanisms associated with various stages of brain inflammation will provide new insights into disease processes associated with neurodegenerative diseases. In this proposal, we aim to delineate a novel anti-inflammatory protective response in the nigrostriatal dopaminergic neurons mediated by the recently discovered mammalian protein homolog of mamba snake venom: Prokineticin-2 (PK2). Unexpectedly, we observed a dramatic up-regulation of PK2 protein and its release from dopaminergic neuronal cells during inflammatory TNF¿ insult. Further observation of increased PK2 expression in nigral dopaminergic neurons in an animal model of PD as well as in the nigral samples from postmortem PD patients provides credence for the clinical significance of our findings. Interestingly, recombinant PK2 significantly protected against apoptotic neuronal cell death and TH positive dopaminergic neuronal loss induced by neuroinflammatory insults. Surprisingly, PK2 treatment also promoted migration of both astrocytes and microglial cells. Therefore, in this proposal, we intend to expand our preliminary observations by pursuing the following specific aims: (i) To characterize the PK2 induction, release and function in dopaminergic neurons following inflammatory insults in primary cell culture and animal models, (ii) To determine the effect of PK2 induction on astroglial and microglial migration and function following inflammatory stimuli, (iii) To investigate the molecular mechanisms of PK2 up-regulation in neuronal cells, and (iv) To demonstrate the neuroprotective effect of PK2 in primary cell culture and animal models of PD. Cellular, molecular and neurochemical approaches will be used to delineate these specific aims. Together, understanding the role of PK2 up-regulation and release during inflammatory stress in dopaminergic neurons will not only provide new insights about neurodegenerative mechanisms underlying nigral dopaminergic degeneration but may also yield novel therapeutic strategies for treatment of Parkinson's disease.