Objective- Vascular calcification (VC) is age dependent and a risk factor for cardiovascular and all-cause mortality. VC involves the senescence-induced transdifferentiation of vascular smooth muscle cells (SMCs) toward an osteochondrogenic lineage resulting in arterial wall mineralization. miR-34a increases with age in aortas and induces vascular SMC senescence through the modulation of its target SIRT1 (sirtuin 1). In this study, we aimed to investigate whether miR-34a regulates VC. Approach and Results- We found that miR-34a and Runx2 (Runt-related transcription factor 2) expression correlates in young and old mice. Mir34a+/+ and Mir34a-/- mice were treated with vitamin D, and calcium quantification revealed that Mir34a deficiency reduces soft tissue and aorta medial calcification and the upregulation of the VC Sox9 (SRY [sex-determining region Y]-box 9) and Runx2 and the senescence p16 and p21 markers. In this model, miR-34a upregulation was transient and preceded aorta mineralization. Mir34a-/- SMCs were less prone to undergo senescence and under osteogenic conditions deposited less calcium compared with Mir34a+/+ cells. Furthermore, unlike in Mir34a+/+ SMC, the known VC inhibitors SIRT1 and Axl (AXL receptor tyrosine kinase) were only partially downregulated in calcifying Mir34a-/- SMC. Strikingly, constitutive miR-34a overexpression to senescence-like levels in human aortic SMCs increased calcium deposition and enhanced Axl and SIRT1 decrease during calcification. Notably, we also showed that miR-34a directly decreased Axl expression in human aortic SMC, and restoration of its levels partially rescued miR-34a-dependent growth arrest. Conclusions- miR-34a promotes VC via vascular SMC mineralization by inhibiting cell proliferation and inducing senescence through direct Axl and SIRT1 downregulation, respectively. This miRNA could be a good therapeutic target for the treatment of VC.
miR-34a Promotes Vascular Smooth Muscle Cell Calcification by Downregulating SIRT1 (Sirtuin 1) and Axl (AXL Receptor Tyrosine Kinase) / I. Badi, L. Mancinelli, A. Polizzotto, D. Ferri, F. Zeni, I. Burba, G. Milano, F. Brambilla, C. Saccu, M.E. Bianchi, G. Pompilio, M.C. Capogrossi, A. Raucci. - In: ARTERIOSCLEROSIS, THROMBOSIS, AND VASCULAR BIOLOGY. - ISSN 1524-4636. - 38:9(2018 Sep), pp. 2079-2090.
|Titolo:||miR-34a Promotes Vascular Smooth Muscle Cell Calcification by Downregulating SIRT1 (Sirtuin 1) and Axl (AXL Receptor Tyrosine Kinase)|
|Parole Chiave:||aging; humans; mice; senescence; vascular calcification; Cardiology and Cardiovascular Medicine|
|Settore Scientifico Disciplinare:||Settore BIO/13 - Biologia Applicata|
|Data di pubblicazione:||set-2018|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1161/ATVBAHA.118.311298|
|Appare nelle tipologie:||01 - Articolo su periodico|