Micromanaging aging with miRNAs: new messages from the nuclear envelope.

Over the last years, the discovery of microRNAs (miRNAs) has revolutionized the classic concepts of gene expression regulation and has introduced a new group of molecules that may contribute to the complex changes observed during aging. Although several Caenorhabditis elegans miRNAs have been proved to influence the nematode life span, the current knowledge about miRNA-mediated regulation of mammalian aging is still limited. Recently, we have analyzed the functional relevance of miRNAs in accelerate aging by using Zmpste24-/- mice, a murine model that phenocopies Hutchinson-Gilford progeria syndrome. These studies have revealed that the nuclear abnormalities present in these mice affect the expression levels of several miRNAs, including a marked upregulation of miR-1 and miR-29. Furthermore, we have found that the altered expression of these miRNAs may contribute to the progeroid phenotype of mutant mice by modulating the levels of key components of the somatroph axis and DNA damage response pathways. Here, we discuss these recent discoveries and summarize the present evidences regarding the involvement of aging-associated miRNAs or geromiRs in senescence and longevity regulation.