Lipid peroxidation in amyloid plaque formation

描述(申请人提供)：这是一份导师研究科学家发展奖(K01)的申请书，旨在发展首席研究员在神经变性和氧化应激领域的研究生涯。这一奖项的目的是为首席研究员提供培训，使他能够在奖项结束时获得NIH的资助，成为神经退行性变和氧化应激领域的独立研究员。培训计划由两部分组成：教育/课程工作/会议和研究。以下是研究计划的摘要。 目前的研究表明，氧化应激，如脂质过氧化，与淀粉样蛋白沉积和斑块形成之间存在相关性。然而，缺乏直接证据表明氧化应激参与淀粉样斑块的形成。这项训练计划中的研究将检验以下假设：脂质过氧化的变化可以影响A-β多肽的沉积，并改变小鼠大脑中淀粉样斑块的水平。这项研究将使用转基因和基因敲除小鼠模型来检验这一假设。将使用两种不同水平的PHGPx(磷脂氢谷胱甘肽-过氧化物酶)小鼠模型：Gpx4基因敲除小鼠(低表达PHGPx)和Gpx4转基因小鼠(高表达PHGPx)。PHGPx由谷胱甘肽过氧化物酶基因4(Gpx4)编码，是一种独特的抗氧化防御酶，能直接解毒细胞膜中的过氧化脂质，被认为是清除细胞膜中过氧化脂质的最重要的酶。这些小鼠将与APP转基因小鼠(Tg2576)杂交，APP转基因小鼠在大脑中形成淀粉样斑块并表现出认知缺陷，以产生PHGPx水平降低或增加的APP小鼠。本研究包括四个具体目标：(1)建立高表达PHGPx的转基因小鼠。(2)检测PHGPx水平降低或升高的APP小鼠脑内脂质过氧化水平。(3)检测PHGPx水平降低或升高的APP小鼠脑内A-β1-42和A-β1-40多肽的水平。(4)检测PHGPx降低或升高的APP转基因小鼠的淀粉样斑块水平。这项研究将是第一次直接测试脂质过氧化在淀粉样斑块形成中的作用。

DESCRIPTION (provided by applicant): This is an application for Mentored Research Scientist Development Award (K01) to develop the Principal Investigator's research career in the area of neurodegeneration and oxidative stress. The goal of this award is to provide the Principal Investigator training that will allow him to become an independent investigator in the area of neurodegeneration and oxidative stress with a funded NIH grant by the end of the award. The training program consists of two parts: education/course work/meetings and research. The following is the summary of the research plan. Current research suggests a correlation between oxidative stress, such as lipid peroxidation, and amyloid deposition and plaque formation. However, direct evidence showing the involvement of oxidative stress in the formation of amyloid plaques is lacking. The research in this training program will test the following hypothesis: alterations in lipid peroxidation can affect the deposition of A-beta peptides and alter the levels of amyloid plaques in the brains of mice. Transgenic and knockout mouse models will be used in this study to test the hypothesis. Two mouse models with different PHGPx (phospholipid hydroperoxide glutathione-eroxidase) levels will be used: Gpx4 knockout mice (under-expressing PHGPx) and Gpx4 transgenic mice (over-expressing PHGPx). PHGPx, which is encoded by the Gpx4 gene (glutathione peroxidase gene 4), is a unique anti-oxidant defense enzyme that can detoxify membrane lipid peroxides directly and is considered to be the most important enzyme in removal of lipid hydroperoxides from ceil membranes. These mice will be crossed to APP transgenic mice (Tg2576), which develop amyloid plaques in the brain and show deficits in cognition, to produce APP mice with decreased or increased PHGPx levels. This study consists of four specific aims: (1) To produce transgenic mice that over express PHGPx. (2) To measure the levels of lipid-eroxidation in brains of APP mice with reduced or increased levels of PHGPx. (3) To measure the levels of A-beta'l-42 and A-beta1-40 peptides in brains of APP mice with reduced or increased levels of PHGPx. (4) To measure the levels of amyloid plaques in APP transgenic mice with reduced or increased PHGPx. This study will be the first direct test of the role of lipid peroxidation in amyloid plaque formation.