Fig. 4: Noncoding RNAs that participate in human brain aging.

a Several microRNAs (miRNAs) enhance neuroprotection in the elderly at the cost of inflammation. The expression of miR-29a/b, miR-34a, and miR-144 increases with age, whereas that of miR-222 decreases. b Long noncoding RNAs (lncRNAs) display age-dependent expression changes with preserved regional specificity. In the prefrontal cortex, the expression levels of the antisense RNA of the gene encoding proline-rich protein (PRR34-AS1), LINC01094, and LINC00844 correlate positively with age. In contrast, the expression levels of the antisense RNA of the gene encoding opacity‐associated (Opa) interacting protein 1 (OIP5-AS1), MIR7-3 host gene (MIR7-3HG), LINC00643, LINC00507, and brain cytoplasmic 200 (BC200) correlate negatively with age. In the subependymal zone, GOMAFU, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), nuclear paraspeckle assembly transcript 1 (NEAT1), and taurine-upregulated gene 1 (TUG1) display age-dependent upregulation, whereas the expression of LINC00657 and small nucleolar RNA, C/D box 3A (SNORD3A) is downregulated with age. c Circular RNAs (circRNAs) tend to accumulate during brain aging, but the function of their accumulation in aging remains unclear.