Genomic Sciences and Biotechnology Program, Catholic University of Brasilia, Brasilia, Brazil.
Genomic Sciences and Biotechnology Program, Catholic University of Brasilia, Brasilia, Brazil; Biosciences Research Institute, Athlone Institute of Technology, Athlone, Co. Westmeath, Ireland.
Cytokine Growth Factor Rev. 2021 Jun;59:9-21. doi: 10.1016/j.cytogfr.2021.01.006. Epub 2021 Jan 29.
Aging is a natural physiological process that features various and variable challenges, associated with loss of homeostasis within the organism, often leading to negative consequences for health. Cellular senescence occurs when cells exhaust the capacity to renew themselves and their tissue environment as the cell cycle comes to a halt. This process is influenced by genetics, metabolism and extrinsic factors. Immunosenescence, the aging of the immune system, is a result of the aging process, but can also in turn act as a secondary inducer of senescence within other tissues. This review aims to summarize the current state of knowledge regarding hallmarks of aging in relation to immunosenescence, with a focus on aging-related imbalances in the medullary environment, as well as the components of the innate and adaptive immune responses. Aging within the immune system alters its functionality, and has consequences for the person's ability to fight infections, as well as for susceptibility to chronic diseases such as cancer and cardiovascular disease. The senescence-associated secretory phenotype is described, as well as the involvement of this phenomenon in the paracrine induction of senescence in otherwise healthy cells. Inflammaging is discussed in detail, along with the comorbidities associated with this process. A knowledge of these processes is required in order to consider possible targets for the application of senotherapeutic agents - interventions with the potential to modulate the senescence process, thus prolonging the healthy lifespan of the immune system and minimizing the secondary effects of immunosenescence.
衰老是一种自然的生理过程，具有各种不同的挑战，与机体内部的内稳态丧失有关，通常会对健康产生负面影响。当细胞耗尽自我更新和组织环境的能力，细胞周期停止时，就会发生细胞衰老。这个过程受遗传、代谢和外在因素的影响。免疫衰老，即免疫系统的衰老，是衰老过程的结果，但也可以反过来成为其他组织衰老的次级诱导因素。本综述旨在总结与免疫衰老有关的衰老特征的当前知识状态，重点关注与骨髓环境相关的衰老相关失衡，以及先天和适应性免疫反应的组成部分。免疫系统的衰老改变了其功能，对个体抵抗感染的能力以及对癌症和心血管疾病等慢性疾病的易感性产生影响。本文描述了衰老相关的分泌表型，以及这种现象在其他健康细胞的旁分泌诱导衰老中的参与。详细讨论了炎症衰老，以及与该过程相关的合并症。为了考虑应用衰老治疗剂的可能靶点，需要了解这些过程——这些干预措施有可能调节衰老过程，从而延长免疫系统的健康寿命，并最小化免疫衰老的次级影响。
