Neuroprotective effects of exogenous brain-derived neurotrophic factor on amyloid-beta 1-40-induced retinal degeneration

• Main Authors: Mohd. Lazaldin, Mohd. Aizuddin, Iezhitsa, Igor, Agarwal, Renu, Agarwal, Puneet, Mohd. Ismail, Nafeeza
• Format: Article
• Language: English
• Published: Wolters Kluwer Medknow Publications 2023
• Subjects: Q Science (General)
• Online Access: http://eprints.utm.my/106032/1/MohdAizuddinMohd2023_NeuroprotectiveEffectsofExogenousBrainDerived.pdf; http://eprints.utm.my/106032/; http://dx.doi.org/10.4103/1673-5374.346546
• Institution: Universiti Teknologi Malaysia

Amyloid-beta (Aβ)-related alterations, similar to those found in the brains of patients with Alzheimer's disease, have been observed in the retina of patients with glaucoma. Decreased levels of brain-derived neurotrophic factor (BDNF) are believed to be associated with the neurotoxic effects of Aβ peptide. To investigate the mechanism underlying the neuroprotective effects of BDNF on Aβ 1-40-induced retinal injury in Sprague-Dawley rats, we treated rats by intravitreal administration of phosphate-buffered saline (control), Aβ 1-40 (5 nM), or Aβ 1-40 (5 nM) combined with BDNF (1 μg/mL). We found that intravitreal administration of Aβ 1-40 induced retinal ganglion cell apoptosis. Fluoro-Gold staining showed a significantly lower number of retinal ganglion cells in the Aβ 1-40 group than in the control and BDNF groups. In the Aβ 1-40 group, low number of RGCs was associated with increased caspase-3 expression and reduced TrkB and ERK1/2 expression. BDNF abolished Aβ 1-40-induced increase in the expression of caspase-3 at the gene and protein levels in the retina and upregulated TrkB and ERK1/2 expression. These findings suggest that treatment with BDNF prevents RGC apoptosis induced by Aβ 1-40 by activating the BDNF-TrkB signaling pathway in rats.