Curcumin Delays Retinal Degeneration by Regulating Microglia Activation in the Retina of rd1 Mice

Cell Physiol Biochem. 2017;44(2):479-493. doi: 10.1159/000485085. Epub 2017 Nov 17.

Abstract

Background/aims: Retinitis pigmentosa (RP) is characterized by degeneration of photoreceptors, and there are currently no effective treatments for this disease. However, curcumin has shown neuroprotectant efficacy in a RP rat and swine model, and thus, may have neuroprotective effects in this disease.

Methods: Immunofluorescence staining, electroretinogram recordings, and behavioral tests were used to analyze the effects of curcumin and the underlying mechanism in retinal degeneration 1 (rd1) mice.

Results: The number of apoptotic cells in the retina of rd1 mice at postnatal day 14 significantly decreased with curcumin treatment and visual function was improved. The activation of microglia and secretion of chemokines and matrix metalloproteinases in the retina were inhibited by curcumin. These effects were also observed in a co-culture of BV2 microglial cells and retina-derived 661W cells.

Conclusions: Curcumin delayed retinal degeneration by suppressing microglia activation in the retina of rd1 mice. Thus, it may be an effective treatment for neurodegenerative disorders such as RP.

Keywords: Curcumin; Microglia; Retinitis pigmentosa; Visual function; rd1 mice.

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Chemokines / metabolism
  • Coculture Techniques
  • Curcumin / pharmacology*
  • Curcumin / therapeutic use
  • Electroretinography
  • Hydrogen Peroxide / toxicity
  • Lipopolysaccharides / toxicity
  • Matrix Metalloproteinases / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Microglia / cytology
  • Microglia / drug effects*
  • Microglia / metabolism
  • Microscopy, Fluorescence
  • Neuroprotective Agents / pharmacology
  • Photoreceptor Cells, Vertebrate / cytology
  • Photoreceptor Cells, Vertebrate / drug effects
  • Photoreceptor Cells, Vertebrate / metabolism
  • Retina / cytology
  • Retina / metabolism
  • Retina / pathology
  • Retinal Degeneration / pathology
  • Retinal Degeneration / prevention & control
  • Retinal Degeneration / veterinary
  • Tissue Inhibitor of Metalloproteinase-1 / metabolism
  • Vascular Cell Adhesion Molecule-1 / metabolism
  • Visual Acuity / drug effects

Substances

  • Chemokines
  • Lipopolysaccharides
  • Neuroprotective Agents
  • Timp1 protein, mouse
  • Tissue Inhibitor of Metalloproteinase-1
  • Vascular Cell Adhesion Molecule-1
  • Hydrogen Peroxide
  • Matrix Metalloproteinases
  • Curcumin