Rapamycin is neuroprotective in a rat chronic hypertensive glaucoma model

PLoS One. 2014 Jun 12;9(6):e99719. doi: 10.1371/journal.pone.0099719. eCollection 2014.

Abstract

Glaucoma is a leading cause of irreversible blindness. Injury of retinal ganglion cells (RGCs) accounts for visual impairment of glaucoma. Here, we report rapamycin protects RGCs from death in experimental glaucoma model and the underlying mechanisms. Our results showed that treatment with rapamycin dramatically promote RGCs survival in a rat chronic ocular hypertension model. This protective action appears to be attributable to inhibition of neurotoxic mediators release and/or direct suppression of RGC apoptosis. In support of this mechanism, in vitro, rapamycin significantly inhibits the production of NO, TNF-α in BV2 microglials by modulating NF-κB signaling. In experimental animals, treatment with rapamycin also dramatically inhibited the activation of microglials. In primary RGCs, rapamycin was capable of direct suppression the apoptosis of primary RGCs induced by glutamate. Mechanistically, rapamycin-mediated suppression of RGCs apoptosis is by sparing phosphorylation of Akt at a site critical for maintenance of its survival-promoting activity in cell and animal model. These results demonstrate that rapamycin is neuroprotective in experimental glaucoma, possibly via decreasing neurotoxic releasing and suppressing directly apoptosis of RGCs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Survival / drug effects
  • Cells, Cultured
  • Chronic Disease
  • Disease Models, Animal
  • Female
  • Glaucoma / pathology*
  • Glaucoma / physiopathology
  • Neuroprotective Agents / pharmacology*
  • Ocular Hypertension / pathology*
  • Ocular Hypertension / physiopathology
  • Rats
  • Rats, Sprague-Dawley
  • Retinal Ganglion Cells / drug effects*
  • Retinal Ganglion Cells / pathology
  • Retinal Ganglion Cells / physiology
  • Sirolimus / pharmacology*

Substances

  • Neuroprotective Agents
  • Sirolimus

Grants and funding

This study was funded by Natural Science Foundation of China (81270992), Natural Science Foundation of Guangdong Province (10251008901000028) and Natural Science Foundation of China (81300740). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.