Basic mechanisms of gene expression modulation: some implications on brain aging

Abstract

Epigenetic and transcriptional regulation are two interconnected processes regulating the activation and deactivation of all genes. This controlled modulation of gene expression determines the phenotype of different cell types, including their morphology, functionality, and ability to respond to diverse conditions. Regulation of epigenetics does not involve changes in the DNA sequence; however, it alters the formation of several protein complexes that are capable of modifying the chromatin structure to modulate the expression of genes. Epigenetic modifications are highly regulated by several factors such as diet, environment, and physical activity. Furthermore, under a disease condition or particular health state, and during aging, changes have been reported in a cell’s epigenome. Notably, aging is considered as a direct risk factor for the development of neurodegenerative diseases. This review presents a general overview of transcriptional regulation and epigenetic mechanisms, and their relationship with the aging process. Alterations in epigenetic mechanisms are evident during aging, which may impact the development of neurodegenerative diseases.