Inactivation of nuclear factor-Y inhibits vascular smooth muscle cell proliferation and neointima formation

OBJECTIVE: Atherosclerosis and restenosis are multifactorial diseases associated with abnormal vascular smooth muscle cell (VSMC) proliferation. Nuclear factor-Y (NF-Y) plays a major role in transcriptional activation of the CYCLIN B1 gene (CCNB1), a key positive regulator of cell proliferation and neointimal thickening. Here, we investigated the role of NF-Y in occlusive vascular disease. APPROACH AND RESULTS: We performed molecular and expression studies in cultured cells, animal models, and human tissues. We find upregulation of NF-Y and cyclin B1 expression in proliferative regions of murine atherosclerotic plaques and mechanically induced lesions, which correlates with higher binding of NF-Y to target sequences in the CCNB1 promoter. NF-YA expression in neointimal lesions is detected in VSMCs, macrophages, and endothelial cells. Platelet-derived growth factor-BB, a main inductor of VSMC growth and neointima development, induces the recruitment of NF-Y to the CCNB1 promoter and augments both CCNB1 mRNA expression and cell proliferation through extracellular signal-regulated kinase 1/2 and Akt activation in rat and human VSMCs. Moreover, adenovirus-mediated overexpression of a NF-YA-dominant negative mutant inhibits platelet-derived growth factor-BB-induced CCNB1 expression and VSMC proliferation in vitro and neointimal lesion formation in a mouse model of femoral artery injury. We also detect NF-Y expression and DNA-binding activity in human neointimal lesions. CONCLUSIONS: Our results identify NF-Y as a key downstream effector of the platelet-derived growth factor-BB-dependent mitogenic pathway that is activated in experimental and human vasculoproliferative diseases. They also identify NF-Y inhibition as a novel and attractive strategy for the local treatment of neointimal formation induced by vessel denudation.This study was funded by the Spanish Ministry of Economy and Competiveness (MINECO; grants SAF2010-16044, SAF200911949), Instituto de Salud Carlos III (ISCIII; grants RD12/0042/0021, RD12/0042/0028, RD12/0042/0053), and the Dr Léon Dumont Prize 2010 by the Belgian Society of Cardiology (to Vicente Andrés). Patricia Fernández received salary support from ISCIII and Carlos Silvestre-Roig from Fundación Mario Losantos del Campo and Fundación Ferrer para la Investigación. Óscar M. Pello and Ricardo Rodríguez-Calvo hold a Juan de la Cierva contract from MINECO. Vanesa Esteban is an investigator of the Sara Borell program from ISCIII (CD06/00232). The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by MINECO and Pro-CNIC Foundation.S