YCG063 inhibits Pseudomonas aeruginosa LPS-induced inflammation in human retinal pigment epithelial cells through the TLR2-mediated AKT/NF-κB pathway and ROS-independent pathways

Int J Mol Med. 2015 Sep;36(3):808-16. doi: 10.3892/ijmm.2015.2266. Epub 2015 Jun 30.

Abstract

YCG063 is known as an inhibitor of reactive oxygen species (ROS); however, its intracellular mechanisms of action remain poorly understood. In the present study, we investigated the effects of YCG063 on the inflammatory response of Pseudomonas aeruginosa lipopolysaccharide (PA-LPS)‑stimulated human retinal pigment epithelial cells (RPE cells). Human adult RPE cells (ARPE‑19) were stimulated with PA-LPS. We then investigated the LPS-induced expression of several inflammatory mediators, such as interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 (MCP-1) and intracellular adhesion molecule-1 (ICAM-1) in the ARPE-19 cells. We performed an enzyme-linked immunosorbent assay (ELISA), western blot analysis, electrophoretic mobility shift assay (EMSA) and fluorescence-activated cell sorting (FACS) to elucidate the mechanisms involved in the anti-inflammatory effects of YCG063 in the PA-LPS-stimulated cells. The results revealed that treatment with YCG063 significantly inhibited the levels of IL-6, IL-8, MCP-1 and ICAM-1 in the PA-LPS-stimulated ARPE-19 cells. YCG063 also markedly inhibited the phosphorylation of AKT in the PA‑LPS-stimulated cells. In addition, the activation of nuclear factor-κB (NF-κB) was also attenuated folllowing treatment with YCG063. ROS were not generated in the PA-LPS-stimulated cells. In conclusion, our data indicate that YCG063 may prove to be a potential protective agent against inflammation, possibly through the downregulation of Toll‑like receptor 2 (TLR2) and the AKT-dependent NF-κB activation pathway in PA-LPS-stimulated ARPE-19 cells. Furthermore, this anti-inflammatory activity occurred through ROS-independent signaling pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anti-Inflammatory Agents / pharmacology*
  • Cell Line
  • Cell Survival / drug effects
  • Humans
  • Hydrazones / pharmacology*
  • Inflammation / drug therapy*
  • Inflammation / immunology
  • Inflammation / microbiology*
  • Lipopolysaccharides / immunology*
  • NF-kappa B / immunology
  • Nitroimidazoles / pharmacology*
  • Proto-Oncogene Proteins c-akt / immunology
  • Pseudomonas aeruginosa / immunology*
  • Reactive Oxygen Species / immunology
  • Retinal Pigment Epithelium / cytology
  • Retinal Pigment Epithelium / drug effects*
  • Retinal Pigment Epithelium / immunology
  • Retinal Pigment Epithelium / microbiology
  • Signal Transduction / drug effects
  • Toll-Like Receptor 2 / immunology

Substances

  • Anti-Inflammatory Agents
  • Hydrazones
  • Lipopolysaccharides
  • NF-kappa B
  • Nitroimidazoles
  • Reactive Oxygen Species
  • Toll-Like Receptor 2
  • YCG 063
  • Proto-Oncogene Proteins c-akt