Nε-carboxymethyl-lysine-induced PI3K/Akt signaling inhibition promotes foam cell apoptosis and atherosclerosis progression

Biomed Pharmacother. 2019 Jul:115:108880. doi: 10.1016/j.biopha.2019.108880. Epub 2019 Apr 28.

Abstract

Advanced glycation end products (AGEs) are closely associated with diabetic macrovascular complications. The present study aimed to investigate the effects of Nε-Carboxymethyl-Lysine (the key active component of AGEs) in diabetic atherosclerosis on foam cell apoptosis and to explore the underlying mechanisms. Tissue sections were collected from 12 Type 2 diabetic patients and 4 control patients who underwent amputation surgery following a car accident. Peritoneal injection of streptozotocin in ApoE-/- mice was used to generate a diabetic model in vivo, and Raw 264.7 cells treated with CML and 740Y-P (a PI3K/AKT signaling agonist) were used to explore the effect of PI3K/AKT signaling in CML-induced foam cell apoptosis in vitro. The anterior tibial section of diabetic amputees contained a thinner fiber cap, higher lipid content, and more apoptotic cells than were found in control patients. in vitro studies using Raw 264.7 cell-derived foam cells and in vivo studies using diabetic ApoE-/- mice showed that CML levels dose-dependently reduced cell vitality, induced foam cell apoptosis and regulated apoptosis related protein. Furthermore, CML significantly decreased the phosphorylation of PI3K/AKT signaling, and restoration of PI3K/AKT signaling by 740Y-P decreased the CML-induced foam cell apoptosis. In conclusion, our results showed CML induced foam cell apoptosis in diabetic atherosclerosis through inhibiting the PI3K/AKT pathway.

Keywords: Apoptosis; Atherosclerosis; Foam cell; Nε-Carboxymethyl-Lysine; PI3K/AKT.

MeSH terms

  • Animals
  • Apoptosis / drug effects*
  • Atherosclerosis / chemically induced*
  • Atherosclerosis / pathology
  • Diabetes Mellitus / pathology
  • Foam Cells / drug effects*
  • Foam Cells / metabolism
  • Humans
  • Lipoproteins, LDL / toxicity
  • Lysine / analogs & derivatives*
  • Lysine / pharmacology
  • Mice
  • Mice, Knockout, ApoE
  • Phosphatidylinositol 3-Kinases / genetics
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / metabolism*
  • RAW 264.7 Cells
  • Tibial Arteries / pathology

Substances

  • Lipoproteins, LDL
  • oxidized low density lipoprotein
  • N(6)-carboxymethyllysine
  • Proto-Oncogene Proteins c-akt
  • Lysine