Gene expression in the aging brain depends on transcription signals generated by senescent physiology, interacting with genetic and epigenetic programs. In turn, environmental factors influence epigenetic mechanisms, such that an epigenetic-environmental link may contribute to the accumulation of cellular damage, susceptibility or resilience to stressors, and variability in the trajectory of age-related cognitive decline. Epigenetic mechanisms, DNA methylation and histone modifications, alter chromatin structure and the accessibility of DNA. Furthermore, small non-coding RNA, termed microRNA (miRNA) bind to messenger RNA (mRNA) to regulate translation. In this review, we examine key questions concerning epigenetic mechanisms in regulating the expression of genes associated with brain aging and age-related cognitive decline. In addition, we highlight the interaction of epigenetics with senescent physiology and environmental factors in regulating transcription.

中文翻译：

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大脑中的衰老：表观遗传学在认知衰退中的新作用。

衰老的大脑中的基因表达取决于衰老生理产生的转录信号，并与遗传和表观遗传程序相互作用。反过来，环境因素影响表观遗传机制，因此表观遗传与环境之间的联系可能有助于细胞损伤的积累，对应激源的敏感性或适应性以及与年龄相关的认知能力下降的轨迹的变异性。表观遗传机制，DNA甲基化和组蛋白修饰，改变染色质结构和DNA的可及性。此外，称为microRNA（miRNA）的小型非编码RNA与信使RNA（mRNA）结合以调节翻译。在这篇综述中，我们研究了与表观遗传机制有关的关键问题，这些表观遗传机制在调节与脑衰老和年龄相关的认知能力下降相关的基因表达中。此外，