title: Protective effects of a grape-supplemented diet in a mouse model of retinal degeneration.
abstract: OBJECTIVE
  Retinal degenerations are a class of devastating blinding diseases that are characterized by photoreceptor dysfunction and death. In this study, we tested whether grape consumption, in the form of freeze-dried grape powder (FDGP), improves photoreceptor survival in a mouse model of retinal degeneration.
  
  
  METHODS
  Retinal degeneration was induced in mice by acute oxidative stress using subretinal injection of paraquat. The grape-supplemented diet was made by formulating base mouse chow with FDGP, corresponding to three daily human servings of grapes, and a control diet was formulated with equivalent sugar composition as FDGP (0.68% glucose-0.68% fructose mixture). Mice were placed on the diets at weaning for 5 wk before oxidative stress injury until analysis at 2 wk post-injection. Retinal function was measured using electroretinography, thickness of the photoreceptor layer was measured using optical coherence tomography, and rows of photoreceptor nuclei were counted on histologic sections.
  
  
  RESULTS
  In mice fed the control diet, oxidative stress significantly reduced photoreceptor layer thickness and photoreceptor numbers. In contrast, retinal thickness and photoreceptor numbers were not reduced by oxidative stress in mice on the grape-supplemented diet, indicating significantly higher photoreceptor survival after injury than mice on the control diet. Furthermore, mice on the grape diet showed preservation of retinal function after oxidative stress injury compared with mice on the control diet.
  
  
  CONCLUSIONS
  A diet supplemented with grapes rescued retinal structure and function in an oxidative stress-induced mouse model of retinal degeneration, which demonstrates the beneficial effect of grapes on photoreceptors.
authors.affiliation: Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA.
authors.forename: Amit K
authors.initials: AK
authors.lastname: Patel
authors.affiliation: Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA.
authors.forename: Ashley
authors.initials: A
authors.lastname: Davis
authors.affiliation: Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA.
authors.forename: Maria Esperanza
authors.initials: ME
authors.lastname: Rodriguez
authors.affiliation: Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA.
authors.forename: Samantha
authors.initials: S
authors.lastname: Agron
authors.affiliation: Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA. Electronic address: ahackam@med.miami.edu.
authors.forename: Abigail S
authors.initials: AS
authors.lastname: Hackam
mesh_terms: D000818:Animals; D004032:Diet; D004195:Disease Models, Animal; D004596:Electroretinography; D005260:Female; D008297:Male; D051379:Mice; D018384:Oxidative Stress / Q000502:physiology; D012160:Retina / Q000473:pathology; D012162:Retinal Degeneration / Q000178:diet therapy*; D027843:Vitis
keywords: Freeze-dried grape powder; Grapes; Neuroprotection; Nutrition; Oxidative stress; Paraquat; Retina; Retinal degeneration