Autophagy is one of the multiple mechanisms active in photoreceptor degeneration

Autophagy. 2007 Jan-Feb;3(1):65-6. doi: 10.4161/auto.3431. Epub 2007 Jan 26.

Abstract

Photoreceptor degeneration in human photoreceptor dystrophies and in the relevant animal models has been thought to be executed by one common mechanism- caspase-mediated apoptosis. However, recent experiments have challenged this concept. Gene defects or environmental stressors appear to cause oxidative stress and altered metabolism, which appear to induce caspase-dependent and caspase-independent cell death mechanisms such as the activation of cysteine-proteases, lysosomal proteases and autophagy and possibly complement-mediated lysis. In this article, we point out mechanistic parallels between these pathways and summarize our recently published investigation using a temporal analysis of the different pathways, which suggests that the noncaspase-dependent mechanisms may actively participate in the demise of the photoreceptors rather than represent a passive response of the retina to the presence of dying cells. Our investigation revealed that unless the common upstream initiator for a given photoreceptor dystrophy can be found, multiple rescue paradigms need to be used to target all active pathways.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review
  • Comment

MeSH terms

  • Animals
  • Autophagy / physiology*
  • Mice
  • Microtubule-Associated Proteins / metabolism
  • Photoreceptor Cells, Vertebrate / metabolism*
  • Protein Denaturation
  • Retinal Degeneration / etiology*
  • Signal Transduction

Substances

  • Map1lc3b protein, mouse
  • Microtubule-Associated Proteins