CD200R promotes high glucose-induced oxidative stress and damage in human retinal pigment epithelial cells by activating the mTOR signaling pathway

Tissue Cell. 2024 Jun:88:102381. doi: 10.1016/j.tice.2024.102381. Epub 2024 Apr 16.

Abstract

Diabetic retinopathy (DR) is established as the primary cause of visual impairment and preventable blindness, posing significant social and economic burdens on healthcare systems worldwide. Oxidative stress has been identified as a major contributor to DR, yet the precise role of the transmembrane glycoprotein CD200R in this context remains elusive. We studied human retinal pigment epithelia ARPE-19 cells to investigate the role of CD200R in high-glucose (HG) induced oxidative stress. Under HG conditions, we found a significant increase in CD200R expression in a time-dependent pattern. Conversely, knockdown of CD200R effectively alleviated oxidative stress and restored cell viability in HG-treated ARPE-19 cells, a phenomenon corroborated by the addition of a reactive oxygen species (ROS) scavenger. Exploration of the AKT/mTOR signaling pathway confirmed its mediating role regarding CD200R knockdown suppression of the expression of key proteins induced by HG conditions. Additionally, we found that the inhibition of mTOR signaling with Rapamycin effectively countered HG-induced oxidative stress in ARPE-19 cells, suggesting a promising therapeutic target against oxidative stress in the context of DR. This study establishes the crucial role of CD200R in HG-induced oxidative stress and identifies potential therapeutic avenues for the treatment of DR.

Keywords: AKT/mTOR signaling; CD200R; Diabetic retinopathy; Oxidative stress.

MeSH terms

  • Cell Line
  • Cell Survival / drug effects
  • Diabetic Retinopathy / metabolism
  • Diabetic Retinopathy / pathology
  • Epithelial Cells / drug effects
  • Epithelial Cells / metabolism
  • Glucose* / pharmacology
  • Humans
  • Orexin Receptors / genetics
  • Orexin Receptors / metabolism
  • Oxidative Stress* / drug effects
  • Reactive Oxygen Species / metabolism
  • Retinal Pigment Epithelium* / drug effects
  • Retinal Pigment Epithelium* / metabolism
  • Retinal Pigment Epithelium* / pathology
  • Signal Transduction* / drug effects
  • TOR Serine-Threonine Kinases* / metabolism

Substances

  • TOR Serine-Threonine Kinases
  • Glucose
  • MTOR protein, human
  • Orexin Receptors
  • CD200R1 protein, human
  • Reactive Oxygen Species