Long noncoding RNAs (lncRNAs) play important roles in the development of
vascular diseases. However, the effect of
lncRNA NORAD on
atherosclerosis remains unknown. This study aimed to investigate the effect NORAD on endothelial cell injury and
atherosclerosis.
Ox-LDL-treated human umbilical vein endothelial cells (HUVECs) and high-fat-diet (HFD)-fed
ApoE-/- mice were used as in vitro and in vivo models. Results showed that NORAD-knockdown induced cell cycle arrest in G0/G1 phase, aggravated
ox-LDL-induced cell viability reduction, cell apoptosis, and cell senescence along with the increased expression of Bax, P53, P21 and cleaved
caspase-3 and the decreased expression of Bcl-2. The effect of NORAD on cell viability was further verified via NORAD-overexpression. NORAD- knockdown increased
ox-LDL-induced
reactive oxygen species,
malondialdehyde, p-IKBα expression levels and NF-κB nuclear translocation. Proinflammatory molecules ICAM, VCAM, and
IL-8 were also increased by NORAD- knockdown. Additionally, we identified the strong interaction of NORAD and
IL-8 transcription repressor SFPQ in HUVECs. In
ApoE-/- mice, NORAD-knockdown increased the
lipid disorder and atherosclerotic lesions. The results have suggested that
lncRNA NORAD attenuates endothelial cell senescence, endothelial cell apoptosis, and
atherosclerosis via NF-κB and p53-p21 signaling pathways and
IL-8, in which NORAD-mediated effect on
IL-8 might through the direct interaction with SFPQ.