Background Glaucoma is an optic neuropathy characterized by loss of function and death of retinal ganglion cells (RGCs), leading to irreversible vision loss. Neuroinflammation is recognized as one of the causes of glaucoma, and currently no treatment is addressing this mechanism. We aimed to investigate the anti-inflammatory and neuroprotective effects of 1,25(OH)(2)D-3 (1 alpha,25-dihydroxyvitamin D-3, calcitriol), in a genetic model of age-related glaucomatous neurodegeneration (DBA/2J mice). Methods DBA/2J mice were randomized to 1,25(OH)(2)D-3 or vehicle treatment groups. Pattern electroretinogram, flash electroretinogram, and intraocular pressure were recorded weekly. Immunostaining for RBPMS, Iba-1, and GFAP was carried out on retinal flat mounts to assess retinal ganglion cell density and quantify microglial and astrocyte activation, respectively. Molecular biology analyses were carried out to evaluate retinal expression of pro-inflammatory cytokines, pNF kappa B-p65, and neuroprotective factors. Investigators that analysed the data were blind to experimental groups, which were unveiled after graph design and statistical analysis, that were carried out with GraphPad Prism. Several statistical tests and approaches were used: the generalized estimated equations (GEE) analysis, t-test, and one-way ANOVA. Results DBA/2J mice treated with 1,25(OH)(2)D-3 for 5 weeks showed improved PERG and FERG amplitudes and reduced RGCs death, compared to vehicle-treated age-matched controls. 1,25(OH)(2)D-3 treatment decreased microglial and astrocyte activation, as well as expression of inflammatory cytokines and pNF-kappa B-p65 (p < 0.05). Moreover, 1,25(OH)(2)D-3-treated DBA/2J mice displayed increased mRNA levels of neuroprotective factors (p < 0.05), such as BDNF. Conclusions 1,25(OH)(2)D-3 protected RGCs preserving retinal function, reducing inflammatory cytokines, and increasing expression of neuroprotective factors. Therefore, 1,25(OH)(2)D-3 could attenuate the retinal damage in glaucomatous patients and warrants further clinical evaluation for the treatment of optic neuropathies.

1α,25-dihydroxyvitamin D3 protects retinal ganglion cells in glaucomatous mice

Lazzara, Francesca
Primo
Conceptualization
;
Platania, Chiara Bianca Maria
Software
;
Conti, Federica
Methodology
;
Drago, Filippo
Funding Acquisition
;
Bucolo, Claudio
Writing – Review & Editing
2021-01-01

Abstract

Background Glaucoma is an optic neuropathy characterized by loss of function and death of retinal ganglion cells (RGCs), leading to irreversible vision loss. Neuroinflammation is recognized as one of the causes of glaucoma, and currently no treatment is addressing this mechanism. We aimed to investigate the anti-inflammatory and neuroprotective effects of 1,25(OH)(2)D-3 (1 alpha,25-dihydroxyvitamin D-3, calcitriol), in a genetic model of age-related glaucomatous neurodegeneration (DBA/2J mice). Methods DBA/2J mice were randomized to 1,25(OH)(2)D-3 or vehicle treatment groups. Pattern electroretinogram, flash electroretinogram, and intraocular pressure were recorded weekly. Immunostaining for RBPMS, Iba-1, and GFAP was carried out on retinal flat mounts to assess retinal ganglion cell density and quantify microglial and astrocyte activation, respectively. Molecular biology analyses were carried out to evaluate retinal expression of pro-inflammatory cytokines, pNF kappa B-p65, and neuroprotective factors. Investigators that analysed the data were blind to experimental groups, which were unveiled after graph design and statistical analysis, that were carried out with GraphPad Prism. Several statistical tests and approaches were used: the generalized estimated equations (GEE) analysis, t-test, and one-way ANOVA. Results DBA/2J mice treated with 1,25(OH)(2)D-3 for 5 weeks showed improved PERG and FERG amplitudes and reduced RGCs death, compared to vehicle-treated age-matched controls. 1,25(OH)(2)D-3 treatment decreased microglial and astrocyte activation, as well as expression of inflammatory cytokines and pNF-kappa B-p65 (p < 0.05). Moreover, 1,25(OH)(2)D-3-treated DBA/2J mice displayed increased mRNA levels of neuroprotective factors (p < 0.05), such as BDNF. Conclusions 1,25(OH)(2)D-3 protected RGCs preserving retinal function, reducing inflammatory cytokines, and increasing expression of neuroprotective factors. Therefore, 1,25(OH)(2)D-3 could attenuate the retinal damage in glaucomatous patients and warrants further clinical evaluation for the treatment of optic neuropathies.
2021
Calcitriol
Cytokines
Glaucoma
Inflammation
Retina
Vitamin D
Animals
Calcitriol
Calcium-Regulating Hormones and Agents
Female
Gene Regulatory Networks
Glaucoma
Mice
Mice, Inbred DBA
Mice, Transgenic
Neuroprotective Agents
Retinal Ganglion Cells
File in questo prodotto:
File Dimensione Formato  
1α,25-dihydroxyvitamin D3.pdf

accesso aperto

Tipologia: Versione Editoriale (PDF)
Dimensione 3.48 MB
Formato Adobe PDF
3.48 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11769/543422
Citazioni
  • ???jsp.display-item.citation.pmc??? 11
  • Scopus 18
  • ???jsp.display-item.citation.isi??? 18
social impact