Mitochondrial Transplantation Strategies to Promote Recovery after Spinal Cord Injury

促进脊髓损伤后恢复的线粒体移植策略

• 批准号: 9210134
• 负责人: Alexander George Rabchevsky
• 金额: $ 18.81万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9210134
• 关键词: Acute; Allogenic; Animals; Antibodies; Area; Astrocytes; Autologous; Behavioral; Bioenergetics; Cell Culture Techniques; Cells; Chronic; Complement; Confocal Microscopy; Data; Dose; Endothelial Cells; Fixatives; Fostering; Frequencies; Functional disorder; Future; Goals; Hindlimb; Histological Techniques; Histology; Homeostasis; Image; Immunohistochemistry; Inflammation; Injectable; Injury; Investigation; Knowledge; Label; Leg; Limb structure; Locomotion; Locomotor Recovery; Measures; Mediating; Microglia; Mission; Mitochondria; Modeling; Multienzyme Complexes; Muscle; Nervous System Trauma; Neurons; Oligodendroglia; Outer Mitochondrial Membrane; Oxidative Stress; Oxygen Consumption; PC12 Cells; Process; Rattus; Recovery; Recovery of Function; Research; Research Proposals; Respiration; Rodent; Seminal; Series; Site; Soleus Muscle; Source; Spinal; Spinal Cord; Spinal Cord Contusions; Spinal cord injury; Subcellular Fractions; Techniques; Testing; Therapeutic; Time; Tissues; Transgenic Organisms; Transplantation; Traumatic injury; United States National Institutes of Health; base; cell type; clinically relevant; comparative; design; dosage; experimental study; gait examination; improved; inflammatory marker; injured; innovation; insight; muscle transplantation; nano; neuroprotection; novel therapeutic intervention; novel therapeutics; prevent; public health relevance; response; stem; targeted treatment; trend

 DESCRIPTION (provided by applicant): The current proposal is designed to develop of a new research area that is aimed at transplanting mitochondria into the injured rodent spinal cord as a therapeutic strategy following traumatic spinal cord injury (SCI). We and others have found that maintaining normal mitochondrial bioenergetics after contusion SCI fosters both neuroprotection and functional recovery. However, no studies have examined the effects of transplanting exogenous mitochondria into spinal cord tissue after injury in an attempt to normalize overall cellular bioenergetics and spare adjacent host tissues. Accordingly, this new line of investigations will test, ultimately, whether transplanting exogenous healthy mitochondria into the injured spinal cord promotes functional neuroprotection. Using a rat model of contusion SCI, we have preliminary data showing that allogeneic transgenically-labeled (turboGFP) mitochondria derived from PC12 cells microinjected around the injury site maintain overall cellular bioenergetics assessed 24 hrs later. Moreover, using confocal microscopy to evaluate specific antibodies to both inner and outer mitochondrial membranes, we have preliminary evidence that grafted turboGFP mitochondria integrate within naïve and injured spinal cord tissues. Based on these seminal findings, we propose to conduct a series of transplantation strategies to deliver mitochondria around the injury sites. The ultimate goal is to identify a potential autologous cell source of mitochondria (i.e., leg muscle) to prevent secondary tissue injury that is mediated, in large part, by mitochondrial loss and dysfunction. In summary, Aim 1a will comparatively employ a dose-response approach to assess whether transplanted MitoTracker Red-labeled mitochondria isolated from muscles are equally effective as allogeneic turboGFP mitochondria on cellular bioenergetics and the extent of inflammation following acute contusion SCI. Aim 1b will then assess comparatively the frequency and distribution of labeled mitochondria incorporated into host cells over the first week post-injury. Finally, Aim 2 will establish whether transplantation of muscle-derived mitochondria increases long-term tissue sparing and recovery of hindlimb locomotion following SCI. This project has translational potential wherein mitochondria, notably autologous, can be transplanted around the injury site to spare penumbral tissues. Based on the collective expertise of the PI in cellular transplantation into injured spinal cord tissue and both Co-Is in bioenergetic assessments and mitochondrial-targeted therapeutics for neurotrauma, along with our preliminary feasibility data, there are no foreseen technical obstacles to successfully carry out this project. Notably, future experiments stemming from the results of the current proposal will be designed to test delayed grafting paradigms to extend a more clinically relevant therapeutic time window for transplantation of mitochondria to promote functional recovery in more chronic SCI models.

 描述（由适用提供）：当前的建议旨在开发一个新的研究领域，该研究旨在将线粒体移植到受伤的啮齿动物脊髓中，作为创伤性脊髓损伤（SCI）后的治疗策略。我们和其他人发现，在挫伤科学后，维持正常的线粒体生物能量促进了神经保护和功能恢复。然而，尚无研究检查在损伤后将外源线粒体移植到脊髓组织中的影响，以试图使整个细胞生物能和备用邻近的宿主组织正常化。根据这一新的研究系，最终将测试将外源性健康的线粒体移植到受伤的脊髓中是否促进功能性神经保护。使用挫伤SCI的大鼠模型，我们有初步数据表明，源自损伤部位周围的PC12细胞的同种异体传递标记（turboGFP）线粒体维持24小时后评估的总体细胞生物能量。此外，使用共聚焦显微镜评估对内部和外部线粒体膜的特异性抗体，我们有初步证据表明，在幼稚和受伤的脊髓组织中嫁接的TurboGFP线粒体移植了。基于这些第二个发现，我们建议进行一系列移植策略，以在伤害部位提供线粒体。最终目标是确定线粒体（即腿部肌肉）的潜在自体细胞来源，以防止通过线粒体损失和功能障碍介导的继发组织损伤。总而言之，AIM 1A将相对采用剂量反应方法来评估从肌肉中分离出的移植的mitotracker红标线粒体是否同样有效，因为同种异体turbogFP线粒体在细胞生物生物生物生物生物生物学的程度和急性污染SCI后的炎症程度上是否同样有效。然后，AIM 1B将在受伤后的第一周中评估掺入宿主细胞中的标记线粒体的频率和分布。最后，AIM 2将确定肌肉衍生的线粒体的移植是否会增加SCI后的长期组织和后肢运动的恢复。该项目已经翻译了潜力，其中线粒体（尤其是自体）可以在损伤部位移植到备用半身组织。基于PI在细胞移植中的集体专业知识，以及在生物能评估中的CO-IS中，以及针对神经疾病的线粒体靶向疗法，以及我们的初步可行性数据，没有预见的技术障碍来成功进行此项目。值得注意的是，根据当前建议的结果，未来的实验将被设计为测试延迟的嫁接范例，以扩展更临床相关的治疗时间窗口，以移植线粒体，以促进更多慢性SCI模型的功能恢复。