Enriched environment housing protects the visual pathway alterations against experimental glaucoma in adult rats

GONZALEZ FLEITAS M FLORENCIA; DIEGUEZ, HERNÁN H.; CHIANELLI MÓNICA S; DEVOUASSOUX, JULIÁN D.; DORFMAN, DAMIÁN; ROSENSTEIN, RUTH E; ARANDA, MARCOS L.; CALANNI, JUAN S.

Chicago

Congreso; Neuroscience 2019- Society for Neuroscience; 2019

Society for Neuroscience

Poster #: 389.04/I32 Topic: C.07. Neurotoxicity/ Inflammation/ and Neuroprotection - Enriched environment housing protects the visual pathway alterations against experimental glaucoma in adult ratsGlaucoma 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 in which animals are exposed to complex conditions through adaptations in the physical and social environment. Since it has been shown that EE provides a better recovery from different neuropathologies, 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 (electroretinogram and flash visual evoked potentials (VEPs)), and histological analysis. EE housing which did not affect IOP, prevented the decrease in VEPs and oscillatory potential amplitude, as well as the RGC loss (assessed by Brn3a-immunoreactivity). The axon number (assessed by toluidine blue staining) was also preserved by the exposure to EE. Moreover, EE housing prevented the decrease in the immunoreactivity for myelin basic protein (MBP) 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, a non-invasive strategy, protects the visual pathway against retina and optic nerve damage induced by experimental glaucoma. Although care must be taken when extrapolating data obtained in experimental models to humans, the protective effect of EE could reflect a scenario in which a physically and mentally active lifestyle promotes the visual pathway resiliency to damage induced by glaucoma.