Enteric Neuronal Aggregation of a-synuclein causes disruption in Colonic Neurotransmission and results in Colonic Dysmotility

摘要 胃肠道(GI)并发症是帕金森病患者的重大临床和经济负担 疾病(PD)。具体来说，便秘是导致24岁以下儿童生活质量下降最严重的原因- 63%的帕金森病患者。然而，由于缺乏对这种症状背后的机制的了解， 没有成功的或长期的治疗方法。众所周知，聚合形式的α- 突触前终末蛋白--突触核蛋白(α-syn)是帕金森病的病理标志 PD患者通过胃肠道的肠道神经系统(ENS)的不同途径。内的α-SYN聚合 在帕金森病患者中，ENS和便秘先于运动障碍长达20年。不管这种蛋白质是不是 目前还不清楚神经内窥镜的神经传递是否受到干扰。我们在重组中的初步数据 在小鼠模型中发现靶向肠神经元的带有A53T点突变的腺相关病毒 结肠推进功能降低，提示α-SYN可能干扰胆碱能神经传递。长的- 本项目的学期目标是确定α-SYN在结肠肌间是否聚集。 神经丛损害Es胆碱能神经肌肉和突触传递导致结肠异常 推进器。为了实现这一项目目标，目标1将确定异位α-SYN在 结肠的肌间神经细胞，因为这将为我们提供关于 蛋白质和神经递质系统。在目标2中，我们将使用体内和体外范式来确定 α-SYN过表达是否通过解决结肠推进和结肠运动而扰乱结肠推进运动 宫缩和放松。目标3将使用光遗传学来确定α-SYN过表达对 肌间神经丛中胆碱能突触和神经肌肉传递。这项拟议的研究将是 第一个直接研究在存在α-SYN聚集体的情况下ENS内的胆碱能神经传递。 此外，我们的目标是确定新的靶点，这些靶点可能会启动治疗便秘的新药发现。 与警方有牵连。

Abstract Gastrointestinal (GI) complications are a significant clinical and economic burden in patients with Parkinson’s disease (PD). Specifically, constipation is responsible for the most drastic decrease in the quality of life for 24- 63% of PD patients. Yet, due to the lack of knowledge of the mechanisms underlying this symptom, there haven’t been successful or long-term therapies. It has been well established that aggregated forms of α- synuclein (α-syn), a presynaptic terminal protein identified to be the pathological marker in PD, is observed diversely through the enteric nervous system (ENS) of the GI tract in PD patients. α-syn aggregation within the ENS as well as constipation precede the motor deficits in PD by up to 20 years. Whether this protein is interfering with neurotransmission in the ENS is currently unknown. Our preliminary data in recombinant adeno-associated virus with A53T point mutation targeted to enteric neurons in the mouse model found reduced colonic propulsion suggesting that α-syn maybe disrupting cholinergic neurotransmission. The long- term objective of this project is to determine whether α-syn aggregation in the colonic myenteric plexus impairs ENS cholinergic neuromuscular and synaptic transmission causing abnormal colonic propulsion. To achieve this project objective, Aim 1 will determine the expression of ectopic α-syn in the myenteric neurons of the colon as this will provide us mechanistic data on the potential interactions between the protein and neurotransmitter systems. In Aim 2 we will use in vivo and ex vivo paradigms to determine whether α-syn overexpression disrupts propulsive colonic motility by addressing colonic propulsion and colonic contractions and relaxations. Aim 3 will use optogenetics to identify the effect of α-syn overexpression on cholinergic synaptic and neuromuscular transmission in the myenteric plexus. This proposed research will be the first to directly study cholinergic neurotransmission within the ENS in the presence of α-syn aggregates. Moreover, we aim to identify novel targets that may initiate new drug discoveries in treating constipation involved in PD.