Enriched environment induces neuroprotection against visual disfunctions within experimental glaucoma in rats

MARÍA FLORENCIA GONZÁLEZ FLEITAS; JULIÁN DANIEL DEVOUASSOUX; MARCOS LUIS ARANDA; JUAN SALVADOR CALANNI; HERNÁN DIEGUEZ; DAMIÁN DORFMAN; MÓNICA CHIANELLI; INES KELLER SARMIENTO; RUTH E. ROSENSTEIN

Congreso; XXXIV Reunión Anual de la SAN; 2019

Glaucoma is a leading cause of blindness, characterized by retinal ganglion cell (RGC) loss and optic nerve (ON) damage. Increased intraocular pressure (IOP) is the most accepted risk factor for glaucomatous neuropathy, however many patients with successful IOP control continue to lose vision. Enriched environment (EE) consists of a manipulation inwhich animals are exposed to complex conditions through adaptations in the physical and social environment. The aim of this work was to analyze whether the exposure to EE is able to prevent glaucomatous damage. Adult male Wistar rats received 30% of chondroitin sulfate in the anterior chamber of one eye and vehicle in the contralateral eye, once a week, and were housed in standard environment (SE) or EE for 10 weeks. Animals were subjected to functional (flash visual evoked potentials (VEPs)), and histological analysis. EE housing which did not affect IOP, prevented the disfunction in VEPs as well as the anterograde transport to visual areas and RGC loss (assessed by Brn3a-immunoreactivity). The axon number was also preservedby the exposure to EE. Moreover, EE housing prevented the decrease in the immunoreactivity for myelin basic protein and luxol fast blue staining in the ON, as well as the increase in Iba1 (a microglia/macrophage marker) positive area in the retina and ON.These results suggest that the EE housing protects the visual pathway against retina and optic nerve damage induced by experimental glaucoma.