1. Academic Validation
  2. Inhibition of microRNA-92a prevents endothelial dysfunction and atherosclerosis in mice

Inhibition of microRNA-92a prevents endothelial dysfunction and atherosclerosis in mice

  • Circ Res. 2014 Jan 31;114(3):434-43. doi: 10.1161/CIRCRESAHA.114.302213.
Xavier Loyer 1 Stéphane Potteaux Anne-Clémence Vion Coralie L Guérin Sheerazed Boulkroun Pierre-Emmanuel Rautou Bhama Ramkhelawon Bruno Esposito Marion Dalloz Jean-Louis Paul Pierre Julia Jean Maccario Chantal M Boulanger Ziad Mallat Alain Tedgui
Affiliations

Affiliation

  • 1 From the INSERM UMR-S 970, Paris Cardiovascular Research Center - PARCC, Université Paris Descartes, Sorbonne Paris Cité, Paris, France (X.L., S.P., A.-C.V., C.L.G., S.B., P.-E.R., B.R., B.E., M.D., C.M.B., Z.M., A.T.); AP-HP (Assistance Publique-Hôpitaux de Paris), Hôpital Européen Georges Pompidou, Service de Biochimie, 75015 Paris, France (J.-L.P.); AP-HP (Assistance Publique-Hôpitaux de Paris), Hôpital Européen Georges Pompidou, Service de Chirurgie Cardiovasculaire, Paris, France (P.J.); INSERM U1018, Université Paris Sud 11, Villejuif, France (J.M.); and Department of Medicine, University of Cambridge, Cambridge, UK (Z.M.).
Abstract

Rationale for study: MicroRNAs (miRNAs) are small noncoding RNAs that regulate protein expression at post-transcriptional level. We hypothesized that a specific pool of endothelial miRNAs could be selectively regulated by flow conditions and inflammatory signals, and as such be involved in the development of atherosclerosis.

Objective: To identify miRNAs, called atheromiRs, which are selectively regulated by shear stress and oxidized low-density lipoproteins (oxLDL), and to determine their role in atherogenesis.

Methods and results: Large-scale miRNA profiling in HUVECs identified miR-92a as an atheromiR candidate, whose expression is preferentially upregulated by the combination of low shear stress (SS) and atherogenic oxLDL. Ex vivo analysis of atheroprone and atheroprotected areas of mouse arteries and human atherosclerotic plaques demonstrated the preferential expression of miR-92a in atheroprone low SS regions. In LDLR(-/-) mice, miR-92a expression was markedly enhanced by hypercholesterolemia, in particular in atheroprone areas of the aorta. Assessment of endothelial inflammation in gain- and loss-of-function experiments targeting miR-92a expression revealed that miR-92a regulated endothelial cell activation by oxLDL, more specifically under low SS conditions, which was associated with modulation of Kruppel-like factor 2 (KLF2), Kruppel-like factor 4 (KLF4), and suppressor of cytokine signaling 5. miR-92a expression was regulated by signal transducer and activator of transcription 3 in SS- and oxLDL-dependent manner. Furthermore, specific in vivo blockade of miR-92a expression in LDLR(-/-) mice reduced endothelial inflammation and altered the development of atherosclerosis, decreasing plaque size and promoting a more stable lesion phenotype.

Conclusions: Upregulation of miR-92a by oxLDL in atheroprone areas promotes endothelial activation and the development of atherosclerotic lesions. Therefore, miR-92a antagomir seems as a new atheroprotective therapeutic strategy.

Keywords

atherosclerosis; endothelium; microRNAs.

Figures