Genes, Environment & Neural Stem Cell Transplantation in the Gut

基因、环境

• 批准号: 7585560
• 负责人: PANKAJ J PASRICHA
• 金额: $ 38.47万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-15 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7585560
• 关键词: Apoptotic; Biological Factors; Congenital Megacolon; Constipation; Data; Deglutition; Development; Disease; Disease model; Embryo; Enteral; Enteric Nervous System; Environment; Enzymes; GDNF gene; Gastrointestinal Motility; Gastrointestinal tract structure; Gastroparesis; Genes; Genetic; Goals; Immune response; Inflammatory; Intestinal Obstruction; Knowledge; Laboratories; Movement; Mus; Muscle; Nausea and Vomiting; Nerve; Nervous System Physiology; Neuraxis; Neuronal Differentiation; Neurons; Neuropathy; Nitric Oxide Synthase Type I; Outcome; Pathway interactions; Peripheral; Pharmaceutical Preparations; Phenotype; Relaxation; Role; Signal Transduction; Societies; Source; Stem cell transplant; Stomach; Symptoms; Techniques; Testing; Therapeutic; Therapeutic Uses; Transplantation; Validation; Work; adult stem cell; burden of illness; clinically relevant; gastrointestinal function; human disease; improved; mutant; nerve stem cell; neurotrophic factor; public health relevance; receptor; research study

DESCRIPTION (provided by applicant): Neural stem cell (NSC) transplantation is an emerging technique with immense promise for the treatment of disorders of the peripheral (PNS) and central nervous system (CNS). More recently, our laboratory has begun investigating the use of NSC as a viable therapeutic strategy for disorders of gastrointestinal motility. Using a strategy of transplanting CNS-derived NSC (CNS-NSC) in mice with a genetic deletion of the neuronal nitric oxide synthase (nNOS) enzyme, we have shown that CNS-NSC can successfully engraft and differentiate into nNOS expressing neurons, can restore nitrergic relaxation and "rescue" gastric function (emptying) in these mice. We have also shown that intrinsic apoptotic signaling is more important in determining the survival of transplanted NSC than the host immune response. The results of these experiments have generated considerable confidence in the viability of this strategy as a potential therapy. Further validation of this approach will require a greater knowledge of the mechanisms responsible for differentiation and survival of NSC in the gut. In this regard, we have initially focused on the most well characterized pathway responsible for the normal development of the enteric nervous system, glial derived neurotrophic factor or GDNF, and its cognate receptor, RET. Our preliminary data, using CNS-NSC transfected with a constitutively active RET mutant (RET/PTC2) suggest that activation of this pathway results in greater proliferation, survival and neuronal differentiation of NSC. Our overall hypothesis is that activation of RET is sufficient to improve the survival and differentiation of CNS-NSC after transplantation into the gut and that this can be an effective therapeutic strategy to replace enteric nervous system function. To test this hypothesis, we will pursue the following specific aims using NSC isolated from the CNS (CNS-NSC) and the gut (ENS-NSC): Specific Aim 1: To use an inducible, constitutively active RET/PTC2 gene construct to determine the duration of RET activation required for an optimal outcome after transplantation. Specific Aim 2: To determine if RET-activation can produce a similar phenotype in either CNS or ENS derived NSC. Specific Aim 3: To determine if RET-activated CNS and ENS-derived NSC can effectively restore enteric neuronal function in clinically relevant models of disease such as Hirschsprung's disease and inflammatory neuropathies. Our long-term objective is to develop neuronal transplantation as a treatment for human diseases of the enteric nervous system. To establish the optimal source of stem cells (adults versus embryonic; CNS versus ENS etc.) currently remains an elusive goal and will need several more years of work by many laboratories across the world. By establishing a permissive and necessary role of RET, the proposed studies will provide the critical groundwork for the therapeutic use of neuronal precursors from a variety of sources. PUBLIC HEALTH RELEVANCE: Disorders of gastrointestinal motility are common and pose a significant burden of disease on our society. These disorders results from disturbances in the function of the nerves and muscle responsible for orderly movement within the digestive tract and result in symptoms such as severe constipation, intestinal obstruction, nausea and vomiting from delayed gastric emptying or difficulty in swallowing. Several of these conditions are caused by loss or abnormal function of gastrointestinal nerves and cannot be treated satisfactorily by drugs alone. An ideal strategy for these disorders is to restore nerve function by transplanting neural stem cells. It is the purpose of this proposal to study this approach experimentally and determine the biological factors that can optimize the use of neural stem cells for the treatment and perhaps cure of these diseases.

描述（由申请人提供）：神经干细胞（NSC）移植是一种新兴技术，对治疗周围疾病（PNS）和中枢神经系统（CNS）的疾病有很大的希望。最近，我们的实验室已开始研究NSC作为胃肠道运动疾病的可行治疗策略。 Using a strategy of transplanting CNS-derived NSC (CNS-NSC) in mice with a genetic deletion of the neuronal nitric oxide synthase (nNOS) enzyme, we have shown that CNS-NSC can successfully engraft and differentiate into nNOS expressing neurons, can restore nitrergic relaxation and "rescue" gastric function (emptying) in these mice.我们还表明，与宿主免疫反应相比，内在凋亡信号传导在确定移植NSC的存活方面更为重要。这些实验的结果对该策略的可行性产生了相当大的信心，作为一种潜在的治疗。对这种方法的进一步验证将需要更多地了解肠道中NSC分化和生存的机制。在这方面，我们最初专注于最有特征的途径，导致肠神经系统，神经胶质衍生的神经营养因子或GDNF及其同源受体RET的正常发育。我们使用用组成型活性RET突变体转染的CNS-NSC（RET/PTC2）的初步数据表明，该途径的激活会导致NSC的更大增殖，存活和神经元分化。我们的总体假设是，RET的激活足以改善移植到肠道后CNS-NSC的生存和分化，这可能是替代肠神经系统功能的有效治疗策略。为了检验这一假设，我们将使用从CNS（CNS-NSC）和肠道（ENS-NSC）分离的NSC追求以下特定目标：特定目的1：使用可诱导的，组成型的RET/PTC2基因构建体以确定移植后最佳结果所需的RET激活持续时间。具体目标2：确定重新激活是否可以在CNS或ENS衍生的NSC中产生类似的表型。特定目的3：确定重新激活的中枢神经系统和ENS衍生的NSC是否可以有效地恢复肠道神经元功能，例如HIRSCHSPRUNG病和炎症性神经病等临床相关模型。我们的长期目标是发展神经元移植作为肠神经系统人类疾病的一种治疗方法。为了建立干细胞的最佳来源（成年人与胚胎； CNS与ENS等）当前仍然是一个难以捉摸的目标，并且将需要全球许多实验室的更多工作。通过建立RET的允许和必要的作用，拟议的研究将为从多种来源的神经元前体提供治疗使用的关键基础。公共卫生相关性：胃肠道运动的疾病很常见，并给我们的社会带来了重大疾病负担。这些疾病是由于导致消化道内有序运动的神经和肌肉功能的干扰而导致的，并导致症状，例如严重的便秘，肠道阻塞，恶心和呕吐，导致胃排空延迟或吞咽困难。这些条件中的几个是由胃肠道神经的丧失或异常功能引起的，不能仅通过药物来令人满意地治疗。这些疾病的理想策略是通过移植神经干细胞来恢复神经功能。该提案的目的是通过实验研究这种方法，并确定可以优化神经干细胞治疗的生物学因素，也许可以治愈这些疾病。