Dose-dependent effect of 11-cis-6mr-retinal on retinal health in Abca4−/−Rdh8−/−mice

The thickness of the ONL and the number of AF spots were evaluated in OCT or SLO images, respectively, obtained from Abca4−/−Rdh8−/− mouse eyes under different treatments. Mice were kept in the dark, treated with DMSO, or with different doses (4, 8, 12, or 20 mg/kg) of 11-cis-6mr-retinal 30 minutes before bright-light illumination. Morphologic changes induced by bright light were largely prevented by pretreatment with 11-cis-6mr-retinal at 20 mg/kg; the ONL thickness and AF spot counts closely resembled those of mice not exposed to bright light. Partial protection was achieved with 11-cis-6mr-retinal at 12 mg/kg. Statistical significance was calculated with the Student’s t test, unpaired two-tailed for two-group comparison, and one-way ANOVA test (SigmaPlot 11.0 software) for multiple group comparison.

TreatmentOCT ONL Thickness Statistical Significance (P)SLO AF, Spot CountsStatistical Significance (P)
µmP valueSpot countsP value
No light58 ± 3NA4 ± 2NA
DMSO4 ± 2NA1200 ± 100NA
11-cis-6mr-retinal (4 mg/kg b.wt.)5 ± 3NS1100 ± 200NS
11-cis-6mr-retinal (8 mg/kg b.wt.)15 ± 10<0.051000 ± 200<0.05
11-cis-6mr-retinal (12 mg/kg b.wt.)27 ± 18<0.001400 ± 100<0.001
11-cis-6mr-retinal (20 mg/kg b.wt.)58 ± 3<0.0014 ± 3<0.001
  • AF, autofluorescence; ANOVA, analysis of variance; DMSO, dimethylsulfoxide; NA, not applicable; NS, not statistically significant; OCT, optical coherence tomography; ONL, outer nuclear layer; SLO, scanning laser ophthalmoscopy.