MiR-590 Inhibits Endothelial Cell Apoptosis by Inactivating the TLR4/NF-κB Pathway in Atherosclerosis

Yonsei Med J. 2019 Mar;60(3):298-307. doi: 10.3349/ymj.2019.60.3.298.

Abstract

Purpose: Previous study has well documented the anti-apoptotic effects of miR-590 on oxidized low-density lipoprotein (ox-LDL)-treated endothelial cells (ECs). However, the mechanism underlying the anti-apoptotic effects of miR-590 in ox-LDL-treated ECs remains to be further addressed.

Materials and methods: ApoE-/- mice fed with a high-fat diet (HFD) and human aortic endothelial cells (HAECs) treated with ox-LDL were used as in vivo and in vitro models of atherosclerosis. The expressions of miR-590 and toll-like receptor 4 (TLR4) were detected by quantitative real-time PCR and Western blot, respectively. Atherosclerotic lesion analysis was performed using Evans blue and hematoxylin-eosin staining. Cell proliferation was assessed by MTT assay. Apoptosis was examined using flow cytometry analysis and Western blot analysis of Cleaved poly (ADP-ribose) polymerase (PARP) and Cleaved Caspase-3 levels. The effect of miR-590 on TLR4/nuclear factor kappa B (NF-κB) pathway was evaluated by Western blot. Binding between miR-590 and TLR4 was confirmed by luciferase reporter assay and Western blot.

Results: miR-590 was downregulated in the aorta tissues from HFD-fed apoE-/- mice and ox-LDL-treated HAECs. miR-590 overexpression inhibited atherosclerotic lesion in HFD-induced apoE-/- mice and promoted proliferation and inhibited apoptosis of ox-LDL-treated HAECs. Additionally, TLR4 was identified as a direct target of miR-590 in ox-LDL-treated HAECs. Moreover, anti-miR-590 reversed TLR4 knockdown-mediated promotion of cell proliferation and suppression of apoptosis in ox-LDL-treated HAECs. miR-590 overexpression suppressed the TLR4/NF-κB pathway, and inhibition of the TLR4/NF-κB pathway promoted cell proliferation and impeded apoptosis in ox-LDL-treated HAECs.

Conclusion: miR-590 promoted proliferation and blocked ox-LDL-induced apoptosis in HAECs through inhibition of the TLR4/NF-κB pathway.

Keywords: ApoE(-/-) mice; MiR-590; TLR4/NF-κB pathway; atherosclerosis; ox-LDL.

MeSH terms

  • Animals
  • Aorta / pathology
  • Apolipoproteins E / deficiency
  • Apolipoproteins E / genetics
  • Apoptosis* / drug effects
  • Apoptosis* / genetics
  • Atherosclerosis / genetics*
  • Atherosclerosis / pathology
  • Base Sequence
  • Cell Proliferation / drug effects
  • Cell Proliferation / genetics
  • Diet, High-Fat
  • Down-Regulation
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism*
  • Endothelial Cells / pathology*
  • Humans
  • Lipoproteins, LDL / pharmacology
  • Male
  • Mice, Inbred C57BL
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • NF-kappa B / metabolism*
  • Signal Transduction / drug effects
  • Signal Transduction / genetics
  • Toll-Like Receptor 4 / metabolism*

Substances

  • Apolipoproteins E
  • Lipoproteins, LDL
  • MIRN590 microRNA, human
  • MIRN590 microRNA, mouse
  • MicroRNAs
  • NF-kappa B
  • Toll-Like Receptor 4
  • oxidized low density lipoprotein