ETD

• environmental enrichment

In this study, we aimed to evaluate the effects of a non-invasive intervention such as environmental enrichment (EE) on murine models of retinitis pigmentosa (RP), Royal College of Surgeons (RCS) rats aged 8 to 12 months. These rats exhibit progressive degeneration of retinal photoreceptors (rods and cones) due to a mutation in the Mertk gene, which compromises the retinal pigment epithelium’s (RPE) ability to phagocytose shed photoreceptor outer segments. Electrophysiological recordings, behavioral tests and assessments of retinal microcirculation were conducted before and after one month of EE. This approach appeared promising. Our results showed that, while scotopic and photopic ERG signals did not improve in enriched models, pERG and mfERG recordings demonstrated a partial recovery of visual function. Behavioral tests revealed enhanced performance in RCS after EE, both in dark–light box and optomotor response (OMR) assays. Similarly, improvements were observed in microcirculation parameters and reduction in reactive oxygen species (ROS) levels in enriched animals. Overall, these findings support the notion that EE represents a possible strategy to promote partial functional recovery of visual signaling in late-stage retinal degeneration murine models, even at advanced age. However, further investigations are required to elucidate the underlying mechanisms and validate these preliminary results.