MicroRNAs in brain aging

Abstract

Brain aging is one of the most crucial biological processes that affect the physiological balance betweenhealth and disease. Age-associated dysfunction of brain leads to severe health problems in current agingsociety. MicroRNAs (miRNAs) have emerged as important regulators in most physiological processesincluding fine-tuning of the short-term, cellular regulatory functions as well as modulation of long-termorganismal lifespan. In this review, we discuss critical roles of miRNAs in the progression of normal andpathological brain aging. 50% of all known miRNAs are found in brain including cortex and hippocam-pus. A significant number of expressed miRNAs were differentially regulated during aging, implicatingmiRNAs as regulators of brain aging. The ability of miRNAs to regulate multiple targets within a pathwayor even multiple pathways allows for coordinated regulation of brain functions. miRNA-mediated, brainfunctional changes are evident in cognition, inflammation, neuroprotection, lipid metabolism, mitochon-drial function and lifespan. Dysregulation of brain miRNAs contributes to accelerated cognitive declineand increased neurological disorders. Elucidating mechanisms by which miRNAs and their multiple tar-gets are temporally and spatially regulated in normal and pathological brain aging will provide a deeperunderstanding on the process of interrelated pathways of brain aging, and a new insight into therapeuticinterventions. © 2017 Elsevier B.V. All rights reserved.