These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Increased micro-RNA 29b in the aged brain correlates with the reduction of insulin-like growth factor-1 and fractalkine ligand. Author: Fenn AM, Smith KM, Lovett-Racke AE, Guerau-de-Arellano M, Whitacre CC, Godbout JP. Journal: Neurobiol Aging; 2013 Dec; 34(12):2748-58. PubMed ID: 23880139. Abstract: Microglia develop an inflammatory phenotype during normal aging. The mechanism by which this occurs is not well understood, but might be related to impairments in several key immunoregulatory systems. Here we show that micro-RNA (miR)-29a and miR-29b, 2 immunoregulatory micro-RNAs, were increased in the brain of aged BALB/c mice compared with adults. Insulin-like growth factor-1 (IGF-1) and fractalkine ligand (CX3CL1) are negative modulators of microglial activation and were identified as targets of miR-29a and miR-29b using luciferase assay and primary microglia transfection. Indeed, higher expression of miR-29b in the brain of aged mice was associated with reduced messenger RNA (mRNA) levels of IGF-1 and CX3CL1. Parallel to these results in mice, miR-29a and miR-29b were also markedly increased in cortical brain tissue of older individuals (mean, 77 years) compared with middle-aged adults (mean, 45 years). Moreover, increased expression of miR-29b in human cortical tissue was negatively correlated with IGF-1 and CX3CL1 expression. Collectively, these data indicate that an age-associated increase in miR-29 corresponded with the reduction of 2 important regulators of microglia, IGF-1 and CX3CL1.[Abstract] [Full Text] [Related] [New Search]