Retinal macroglial activation over time in an experimental glaucoma model

  1. José A. Fernández-Albarral 1
  2. José A. Matamoros 1
  3. Lejing Chen 1
  4. Elena Salobrar-Garcia 11
  5. Inés López-Cuenca 1
  6. Lidia Sanchez-Puebla 1
  7. María Pilar Rojas Lozano 1
  8. Rosa De Hoz 11
  9. Jose Manuel Ramirez 11
  10. Juan Jose Salazar 11
  11. Ana Isabel Ramirez 11
  1. 1 Universidad Complutense de Madrid
    info

    Universidad Complutense de Madrid

    Madrid, España

    ROR 02p0gd045

Proceedings:
Acta Ophthalmologica

Publisher: Wiley

ISSN: 1755-375X 1755-3768

Year of publication: 2022

Volume: 100

Issue: S275

Congress: the 2022 European Association for Vision and Eye Research Festival, 13-15 October 2022, Valencia

Type: Conference paper

DOI: 10.1111/J.1755-3768.2022.0482 GOOGLE SCHOLAR lock_openOpen access editor

Abstract

Purpose: The aim of this study was to analyse the effects of unilateral laser-induced ocular hypertension (OHT) on macroglia in OHT and contralateral eyes at different time points after laser treatment (1, 3, 5, 8 and 15 days).Methods: Two groups of albino Swiss mice: naïve group (n = 6) and OHT group (n = 30, six animals for each time study group). In the OHT group, OHT was induced by laser photocoagulation of the limbal and episcleral veins of the left eyes. Retinal whole-mounts were used to visualize the astroglial plexus throughout the retinal extension, analysing the GFAP-labelled retinal area (GFAP-RA), the intensity of GFAP labeling (GFAP-IRI), and the intensity of MHC-II expression (MHC-II-IRI) in both OHT eyes and normotensive contralateral eyes compared to naïve eyes.Results: In OHT and contralateral eyes, with respect to naïve eyes, at all the time points, we found the following: (i) astrocytes with thicker somas and more secondary processes, mainly in the intermediate (IR) and peripheral retina (PR); (ii) astrocytes with low GFAP-IRI and only primary processes near the optic disc (OD); (iii) increased total GFAP-RA, which was higher at 3 and 5 days, except for at 15 days; (iv) increased GFAP-IRI in the IR and especially in the PR: (v) decreased GFAP-IRI near the OD, mainly at 1 and 5 days; (vi) a significant increase in MHC-II-IRI, which was higher in the IR and PR; and (vii) GFAP+ and MHC-II+ immunolabelling in the Müller glia.Conclusions: Increased IOP leads, both in OHT eyes and in their normotensive contralateral eye, to macroglial activation, demonstrated both by morphologic changes and by the overexpression of GFAP and MHC-II. The main signs of activation were observed mainly in the IR and PR, being more intense at 3 and 5 days after induction. However, in the OD, astrocytes showed low expression of GFAP and MHC-II. The bilateral macroglial activation observed in this study would be triggered by the immune response associated with neuroinflammation.