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衰老和年龄相关疾病的化学和生物学

Chemistry and biology of aging and age-related diseases
课程网址: http://videolectures.net/NIBsimpozij2017_radman_age_diseases/  
主讲教师: Miroslav Radman
开课单位: 地中海生命科学研究所
开课时间: 2017-12-09
课程语种: 英语
中文简介:
蛋白质直接或间接地进行所有生命活动,并受到氧化损伤。自从大气中的氧气从1%增加到21%以来,伴随着从无氧生物向有氧生物的转变,蛋白质在强大的选择压力下进化出抗氧化结构,导致大多数蛋白质显著抵抗活性氧(ROS)造成的损害。然而,这种内在抗性是脆弱的:微妙的生物合成和折叠错误,以及“沉默”错义突变(多态性)导致抗氧化性丧失,并产生潜在的表型后果(例如,疾病易感性)(1)。蛋白质错误折叠和氧化之间存在竞争性对抗:错误折叠的蛋白质要么通过伴侣重新折叠并变得抗氧化,要么通过氧化阻止重新折叠。我们发现有证据表明,细胞的功能退化(类似于衰老)及其死亡主要是由于辐射或衰老造成的氧化蛋白质损伤导致的蛋白质组失效(1-3)。DNA损伤的持续性是修复蛋白质组损伤的后果,修复蛋白质组似乎是细胞死亡的主要原因(1-4)。在细胞死亡之前,可以证明表型(功能)缺陷与蛋白质损伤成正比,并在其减少时可逆(1)。由于专用蛋白质携带所有DNA交易,例如修复、复制和基因表达,我们表明选择性非致死性蛋白质组损伤也会导致突变率的高增加(1)。因此,由于选择性蛋白质组损伤模拟了关键的衰老表型,我们认为衰老本身是累积蛋白质组损伤的渐进复杂表型(1,4)。我将提供的数据表明,蛋白质羰基化不仅是人类衰老的生物标志物——随着年龄的增长,如疾病和死亡的发生率呈指数增长(5)——而且是衰老和所有年龄相关疾病最可能的根本原因。最后,体重、代谢、寿命和疾病潜伏期之间的相关性将通过活性氧的变化和细胞缺陷的表型抑制(组织内稳态)来解释。
课程简介: Proteins carry on, directly or indirectly, all life activities and are subject to oxidative damage. Ever since the increase in atmospheric oxygen from about 1 to 21%, accompanied by the shift from anaerobic to aerobic life, proteins were under strong selective pressure to evolve oxidation-resistant structures resulting in remarkable resistance of most proteins to damage inflicted by reactive oxygen species (ROS). However, this intrinsic resistance is fragile: subtle biosynthetic and folding errors, as well as “silent” missense mutations (polymorphisms) lead to the loss of oxidation resistance, with latent phenotypic consequences (e.g., disease predisposition) (1). There is a competitive antagonism between protein misfolding and oxidation: misfolded proteins either refold by chaperons and become oxidation-resistant, or they undergo oxidation that precludes refolding. We found evidence that functional degeneracy of cells (akin to ageing) and their death result primarily from proteome failure due to oxidative protein damage inflicted by radiation or aging (1-3). Persistence of DNA damage is the consequences of damage to repair proteome that appears as the primary cause of cell death (1-4). Before cell death, phenotypic (functional) deficiencies can be demonstrated that are proportional to protein damage and reversible upon their decrease (1). Since the dedicated proteins carry all DNA transactions, e.g., repair, replication and gene expression, we show that selective non-lethal proteome damage results also in high increase in mutation rates (1). Thus, because the selective proteome damage mimics key aging phenotypes, we posit that aging itself is the progressive complex phenotype of the accumulating proteome damage (1,4). I shall present data suggesting that protein carbonylation is not only a biomarker of human aging - increasing exponentially with age like the incidence of diseases and death (5) - but the most likely root cause of aging and of all age-related diseases. Finally, the correlations between body mass, metabolism, longevity and disease latency will be interpreted by variations in ROS and phenotypic suppression of cell defects (tissue homeostasis).
关 键 词: 蛋白质; 细胞的功能退化; DNA损伤
课程来源: 视频讲座网
数据采集: 2022-03-27:zkj
最后编审: 2022-03-27:zkj
阅读次数: 49