Insoluble protein carbonyl: A critical determinant for mammalian longevity

描述（由申请人提供）：现在文献中充分记载了蛋白质的翻译后变化，特别是蛋白质羰基化，随着动物年龄的增加而发生，从无脊椎动物，例如，酵母和果蝇，对人类来说。羰基化蛋白质随着时间积累，如果它们逃脱蛋白酶体的降解，则形成高分子量的不溶性聚集体。不溶性聚集体的积累已被证明对细胞具有极大的毒性，并与几种年龄相关的疾病，特别是神经退行性疾病有关。最近在我的实验室中对各种短寿命（实验室小鼠、野生捕获小鼠、大鼠）和长寿命（裸鼹鼠、蝙蝠和绒猴）哺乳动物物种（包括近交系自由采食和饮食（DR）限制的幼龄和老龄C57 BL/6小鼠）的研究首次显示了一个意想不到的普遍观察结果，即长寿命物种比短寿命物种具有低水平的不溶性细胞蛋白羰基。该数据强烈表明，长寿命物种似乎比短寿命物种具有更好的能力来减弱不溶性蛋白质羰基的积累。由于羰基化的蛋白质通常被蛋白酶体标记为蛋白质水解，我们推测活跃的蛋白酶体功能可能是长寿物种用于保持蛋白质质量的防御机制之一。我们对啮齿类动物的初步研究发现，活跃的蛋白酶体功能与寿命延长之间存在直接关联。综上所述，拟议的研究将扩大这些有趣的初步观察，以评估长寿物种表现出不溶性蛋白质羰基积累减少，并通过激活蛋白酶体机制维持细胞活力的一般假设。在这个提议中，我们想使用各种非传统的短寿命和长寿命物种的成纤维细胞来测试假设。该项目代表了第一项严格评估蛋白质羰基化和蛋白酶体功能之间串扰的研究，蛋白酶体功能在保护细胞免受广泛哺乳动物蛋白质毒性方面发挥着关键作用。这些数据将使我们能够确定降低蛋白质毒性是否是进化过程中用于延长寿命的常见/公共机制。本提案将通过追求以下具体目标来检验这一假设。具体目标1。为了验证以下假设：蛋白酶体功能的有效响应、不溶性蛋白质羰基的减少和细胞活力的恢复是长寿物种的成纤维细胞响应氧化应激的共同特征。具体目标2。检验蛋白酶体功能失活启动不溶性蛋白羰基积累导致长寿物种成纤维细胞死亡增加的假设。

DESCRIPTION (provided by applicant): It is now well documented in literature that post-translational changes in protein, particularly protein carbonylation, occur with increasing age in animals ranging from invertebrates, e.g., yeast and Drosophila, to humans. Carbonylated proteins accumulate over time to form high molecular weight insoluble aggregates if they are escaped degradation by the proteasome. Accumulation of insoluble aggregates has been shown to be extremely toxic to cells and to be associated with several age-related diseases, especially neurodegenerative diseases. Recent work in my laboratory on various short- (lab mouse, wild caught mouse, rat) and long-lived (naked mole rat, bat and marmoset) mammal species including inbred ad libitum and dietary (DR) restricted young and old C57BL/6 mice has shown for the first time an unexpected generalized observation that long- lived species have low level of insoluble cellular protein carbonyl than short-lived species. This data strongly suggests that long lifespan species seems to have better ability to attenuate accumulation of insoluble protein carbonyl than short-lived species. Since carbonylated proteins in general are marked for proteolysis by the proteasome, we speculated that active proteasomal function might be one of the defense machineries used by long-lived species to maintain good quality of proteins. Our preliminary study with rodent species found a direct association between active proteasomal function and increased longevity. Taken these together, the proposed research would expand these intriguing initial observations to evaluate the general hypothesis that long-lived species exhibit reduced accumulation of insoluble protein carbonyl and maintain cell viability via activation of proteasomal machinery. In this proposal, we would like to use variety of non-traditional short- and long-lived species fibroblast cells to test the hypothesis. This project represents the first study to critically evaluate the crosstalk between protein carbonylation and proteasomal function which play a critical role in protecting cells from protein toxicity across a broad range of mammals. These data will allow us to determine if reduced protein toxicity is a common/public mechanism used by evolutionary processes to increase longevity. This proposal will test the hypothesis by pursuing the following specific aims. Specific Aim 1. To test the hypothesis that efficient response of proteasomal function, reduction in insoluble protein carbonyl and restoring cell viability are common traits for fibroblast cells of long-lived species n response to oxidative stress. Specific Aim 2. To test the hypothesis that inactivation of proteasomal function initiates accumulation of insoluble protein carbonyl which lead to increase cell death in fibroblast of long-lived species.