Jazwinski S Michal, Kim Sangkyu
Tulane Center for Aging, Department of Medicine, Tulane University Health Sciences Center, Tulane School of Medicine, New OrleansLA, United States.
Front Genet. 2017 May 23;8:64. doi: 10.3389/fgene.2017.00064. eCollection 2017.
Biological age is a concept that takes into account the heterogeneity of the aging process in different individuals that results in differences in survival and variations in relative health. Any measure of biological age must be better than chronological age at predicting mortality. Several quantitative measures of biological age have been developed. Among them are frailty indices, one of which called FI is discussed here in greater detail. FI increases exponentially with age reflecting decline in health and function ability. It readily depicts different patterns and trajectories of aging, and it is moderately heritable. Thus, it has been used to identify a genomic region on chromosome 12 associated with healthy aging. FI has also been useful in describing the metabolic characteristics of this phenotype, revealing both sex and genetic differences. These differences give rise to specific, testable models regarding healthy aging, which involve cell and tissue damage and mitochondrial metabolism. FI has been directly compared to various metrics based on DNA methylation as a predictor of mortality, demonstrating that it outperforms them uniformly. This and other frailty indices take a top-down, systems based view of aging that is cognizant of the integrated function of the complex aging system.
生物学年龄是一个考虑到不同个体衰老过程异质性的概念，这种异质性导致了生存差异和相对健康状况的变化。任何生物学年龄的衡量指标在预测死亡率方面都必须优于实际年龄。已经开发了几种生物学年龄的定量测量方法。其中包括衰弱指数，这里将更详细地讨论其中一种称为FI的指数。FI随年龄呈指数增长，反映了健康和功能能力的下降。它很容易描绘出不同的衰老模式和轨迹，并且具有中度遗传性。因此，它已被用于识别与健康衰老相关的12号染色体上的一个基因组区域。FI在描述这种表型的代谢特征方面也很有用，揭示了性别和遗传差异。这些差异产生了关于健康衰老的特定可测试模型，其中涉及细胞和组织损伤以及线粒体代谢。FI已直接与基于DNA甲基化作为死亡率预测指标的各种度量进行比较，表明它在所有方面都优于它们。这种以及其他衰弱指数采用了一种自上而下、基于系统的衰老观点，这种观点认识到复杂衰老系统的综合功能。
