Squamosamide derivative FLZ protects retinal pigment epithelium cells from oxidative stress through activation of epidermal growth factor receptor (EGFR)-AKT signaling

Int J Mol Sci. 2014 Oct 17;15(10):18762-75. doi: 10.3390/ijms151018762.

Abstract

Reactive oxygen species (ROS)-mediated retinal pigment epithelium (RPE) cell apoptosis is attributed to age-related macular degeneration (AMD) pathogenesis. FLZ, a novel synthetic squamosamide derivative from a Chinese herb, Annona glabra, has displayed significant cyto-protective activity. In the current study, we explored the pro-survival effect of FLZ in oxidative stressed-RPE cells and studied the underlying signaling mechanisms. Our results showed that FLZ attenuated hydrogen peroxide (H2O2)-induced viability decrease and apoptosis in the RPE cell line (ARPE-19 cells) and in primary mouse RPE cells. Western blotting results showed that FLZ activated AKT signaling in RPE cells. The AKT-specific inhibitor, MK-2206, the phosphoinositide 3-kinase (PI3K)/AKT pan inhibitor, wortmannin, and AKT1-shRNA (short hairpin RNA) depletion almost abolished FLZ-mediated pro-survival/anti-apoptosis activity. We discovered that epidermal growth factor receptor (EGFR) trans-activation mediated FLZ-induced AKT activation and the pro-survival effect in RPE cells, and the anti-apoptosis effect of FLZ against H2O2 was inhibited by the EGFR inhibitor, PD153035, or by EGFR shRNA-knockdown. In conclusion, FLZ protects RPE cells from oxidative stress through activation of EGFR-AKT signaling, and our results suggest that FLZ might have therapeutic values for AMD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Benzeneacetamides / pharmacology*
  • Cell Line
  • Cell Survival / drug effects
  • Cells, Cultured
  • ErbB Receptors / metabolism*
  • Humans
  • Hydrogen Peroxide / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Oxidative Stress / drug effects*
  • Phenols / pharmacology*
  • Phosphatidylinositol 3-Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Reactive Oxygen Species / metabolism
  • Retinal Pigment Epithelium / cytology
  • Retinal Pigment Epithelium / drug effects*
  • Retinal Pigment Epithelium / metabolism
  • Signal Transduction / drug effects

Substances

  • Benzeneacetamides
  • Phenols
  • Reactive Oxygen Species
  • squamosamide
  • Hydrogen Peroxide
  • Phosphatidylinositol 3-Kinases
  • ErbB Receptors
  • Proto-Oncogene Proteins c-akt