Manipulation of Mitochondrial Genomes in Aging and Neurodegeneration

衰老和神经退行性疾病中线粒体基因组的调控

• 批准号: 7157217
• 负责人: JAMES PEPPER BENNETT
• 金额: $ 46.33万
• 依托单位: GENCIA CORPORATION
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-15 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7157217
• 关键词: DNA damage; RNA interference; age difference; aging; animal old age; animal puberty; apoptosis; biotechnology; cell line; cytotoxicity; fibroblasts; gene delivery system; gene therapy; genetically modified animals; laboratory mouse; mitochondrial DNA; mitochondrial disease /disorder; neural degeneration; oxidative stress; phenotype; platelets; technology /technique development; therapy design /development; transfection

DESCRIPTION (provided by applicant): Mitochondrial DNA (mtDNA) accumulates mutations with aging in human beings and animal models of accelerated mtDNA mutagenesis produce advanced aging phenotypes such as osteoporosis, cardiomyopathy, neurodegeneration, hair loss, anemia and reduced fertility. Though compelling, these animal models are insufficient to prove that mtDNA is responsible for aging phenotypes. If mtDNA could be delivered to mitochondria in vivo, the role of mtDNA in aging could be directly addressed. In conjunction with the Center for the Study of Neurodegenerative Disease (CSND) at the University of Virginia, in a Phase I STTR, Gencia Corporation successfully utilized a method to transfect mitochondria with full-length mtDNA. This was done by using a novel mitochondrial transfection technology, Protofection? (Protein Mediated Transfection), a technology developed and solely owned by Gencia Corporation. Protofection is a DNA-binding, non-viral delivery vector consisting of an engineered recombinant protein that targets mitochondria for DNA delivery. Additional data beyond the aims of the Phase I study show that protofection can deliver and express a full-length mtDNA engineered to express a reporter protein (GFP, Green Fluorescent Protein), in vivo and that delivery of normal mtDNA can ameliorate metabolic defects in cytoplasmic hybrid (cybrid) cells made from aged human subjects. The mechanism by which the mitochondrial transfection technology delivers mtDNA to mitochondria was also discovered and suggests the existence of mitochondrial lipid rafts. In this Phase II STTR, Gencia Corporation and the CSND propose to address the contribution of mitochondrial genomic damage to aging phenotypes by transfecting normal mtDNA into aged mice and mtDNA from aged mice into young mice. The proposed mtDNA transfection experiments will directly determine which aspects of aging phenotypes are caused by mtDNA and which can be reversed by the delivery of normal mtDNA. Efficacy in ameliorating specific phenotypes of aging (which may include sarcopenia, cognitive decline, osteoporosis and others) will be the basis of Investigational New Drug (IND) applications to the FDA/CBER (Center for Biologics Evaluation and Research) for the use of mtDNA gene therapy in these conditions. By 2030, an unprecedented 20% of the population will be over age 65. Since mutations in mitochondrial DNA may be responsible for many aging phenotypes, having a therapy for mitochondrial DNA may reduce this burden. The research proposed in this Phase II STTR will directly address what aging phenotypes are caused by mitochondrial DNA and whether these phenotypes can be reversed.

描述（由申请人提供）：线粒体DNA（mTDNA）在人类中累积了突变，而加速mtDNA诱变的动物模型会产生高级衰老表型，例如骨质疏松症，心肌病，神经变性，神经变性，脱落，脱发，障碍和生育力。尽管令人信服，但这些动物模型不足以证明mtDNA负责老化表型。如果可以将mtDNA输送到体内线粒体，则可以直接解决mtDNA在衰老中的作用。与弗吉尼亚大学的神经退行性疾病研究中心（CSND）结合使用，在I期STTR中，Gencia Corporation成功地利用了一种方法，将线粒体与全长mtDNA转染。这是通过使用新型的线粒体转染技术原理来完成的？ （蛋白质介导的转染），这是一种由Gencia Corporation开发的技术，仅由Gencia Corporation拥有。原色是一种DNA结合的非病毒递送载体，该载体由靶向线粒体靶向DNA递送的工程重组蛋白组成。其他数据超出了第一阶段研究的目的，该数据表明，原构可以传递和表达全长的mtDNA，该MTDNA旨在表达记者蛋白质（GFP，绿色荧光蛋白），体内和正常mtDNA的递送可以在细胞质杂种（cybrid）细胞中的细胞代谢缺损递送。线粒体转染技术将mtDNA传递到线粒体的机制也被发现，并表明存在线粒体脂质筏的存在。在此II期STTR中，Gencia Corporation和CSND建议通过将正常的mtDNA转染到老年小鼠中，以解决线粒体基因组损伤对衰老表型的贡献。提出的mtDNA转染实验将直接确定衰老表型的哪些方面是由mtDNA引起的，并且可以通过正常mtDNA的递送来逆转。改善衰老的特定表型（包括肌肉减少症，认知能力下降，骨质疏松症等）的功效将是对FDA/CBER（生物学评估和研究中心）进行研究的基础，以在这些条件下使用mtDNA基因治疗。到2030年，空前的20％人口将超过65岁。由于线粒体DNA中的突变可能导致许多衰老的表型，因此对线粒体DNA进行治疗可能会减轻这种负担。在此II期STTR中提出的研究将直接解决线粒体DNA引起的衰老表型以及这些表型是否可以逆转。