First Author | Greig FH | Year | 2017 |
Journal | J Am Heart Assoc | Volume | 6 |
Issue | 9 | PubMed ID | 28893763 |
Mgi Jnum | J:276532 | Mgi Id | MGI:6307314 |
Doi | 10.1161/JAHA.117.006936 | Citation | Greig FH, et al. (2017) PEA-15 (Phosphoprotein Enriched in Astrocytes 15) Is a Protective Mediator in the Vasculature and Is Regulated During Neointimal Hyperplasia. J Am Heart Assoc 6(9) |
abstractText | BACKGROUND: Neointimal hyperplasia following angioplasty occurs via vascular smooth muscle cell proliferation. The mechanisms involved are not fully understood but include mitogen-activated protein kinases ERK1/2 (extracellular signal-regulated kinases 1 and 2). We recently identified the intracellular mediator PEA-15 (phosphoprotein enriched in astrocytes 15) in vascular smooth muscle cells as a regulator of ERK1/2-dependent proliferation in vitro. PEA-15 acts as a cytoplasmic anchor for ERK1/2, preventing nuclear localization and thereby reducing ERK1/2-dependent gene expression. The aim of the current study was to examine the role of PEA-15 in neointimal hyperplasia in vivo. METHOD AND RESULTS: Mice deficient in PEA-15 or wild-type mice were subjected to wire injury of the carotid artery. In uninjured arteries from PEA-15-deficient mice, ERK1/2 had increased nuclear translocation and increased basal ERK1/2-dependent transcription. Following wire injury, arteries from PEA-15-deficient mice developed neointimal hyperplasia at an increased rate compared with wild-type mice. This occurred in parallel with an increase in a proliferative marker and vascular smooth muscle cell proliferation. In wild-type mice, PEA-15 expression was decreased in vascular smooth muscle cells at an early stage before any increase in intima:media ratio. This regulation of PEA-15 expression following injury was also observed in an ex vivo human model of hyperplasia. CONCLUSIONS: These results indicate, for the first time, a novel protective role for PEA-15 against inappropriate vascular proliferation. PEA-15 expression may also be repressed during vascular injury, suggesting that maintenance of PEA-15 expression is a novel therapeutic target in vascular disease. |