Enterococcus faecalis lipoteichoic acid regulates macrophages autophagy via PI3K/Akt/mTOR pathway

Biochem Biophys Res Commun. 2018 Apr 15;498(4):1028-1036. doi: 10.1016/j.bbrc.2018.03.109. Epub 2018 Mar 19.

Abstract

Enterococcus faecalis (E. faecalis) infection is considered an important etiological factor for the development of persistent apical periodontitis (PAP), but the exact mechanisms of autophagy between E. faecalis and immune cells remain unknown. In this study, we elucidated how E. faecalis lipoteichoic acid (LTA) is associated with macrophages autophagy. We found that E. faecalis LTA apparently activated macrophage autophagy with significant increase of autophagosomes and autophagy relative protein. Meanwhile, we noticed significantly decreasing expression of p-Akt and p-mTOR. However, these effect were absent in macrophages knockdown of Beclin1. In summary, these findings suggested E. faecalis LTA may increased macrophages autophagy via inhibiting PI3K/Akt/mTOR pathway and this process was Beclin1 dependent.

Keywords: Autophagy; Beclin1; Enterococcus faecalis; Lipoteichoic acid; Macrophages; PI3K/Akt/mTOR.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autophagy / drug effects*
  • Beclin-1
  • Enterococcus faecalis / pathogenicity
  • Lipopolysaccharides / pharmacology*
  • Macrophages / cytology*
  • Macrophages / drug effects
  • Mice
  • Phosphatidylinositol 3-Kinase / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • RAW 264.7 Cells
  • Signal Transduction / drug effects
  • TOR Serine-Threonine Kinases / metabolism
  • Teichoic Acids / pharmacology*

Substances

  • Beclin-1
  • Becn1 protein, mouse
  • Lipopolysaccharides
  • Teichoic Acids
  • lipoteichoic acid
  • mTOR protein, mouse
  • Phosphatidylinositol 3-Kinase
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases