Brain-derived neurotrophic factor (BDNF) gene polymorphism in a cohort of Egyptian primary open-angle glaucoma (POAG) patients

Abstract

Background: Glaucoma is the second leading cause of blindness in the world with primary open-angle glaucoma (POAG) that is the most prevalent type. Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family synthesized by retinal ganglion cells (RGCs). Disturbance of axonal transport of neurotrophins with optic nerve dystrophy results in deprivation of BDNF support to the RGCs inducing glaucomatous retinal cell death. Materials and methods: This case-control study was conducted on 50 POAG patients (mean age 55 ± 10) and 50 healthy control subjects (mean age 40 ± 11). Both groups underwent full ophthalmological examination. Genomic DNA was extracted followed by BDNF rs2030324 genotyping by real time PCR. Results: Correlation coefficient analysis showed significant positive correlation between age and right and left cup to disc ratio (r = 0.448, p = 0.001; r = 0.283, p = 0.004 respectively) and significant negative correlation between intraocular pressure and right and left VA (r = − 0.212, p = 0.034; r = − 0.258, p = 0.009 respectively). No significant difference between the 2 groups was found as regards genotype or alleles frequency distribution (p = 0.722). Conclusion: This study did not succeed to illustrate the role of BDNF gene polymorphism (SNP rs2030324) as a risk factor for POAG occurrence. The mechanism of glaucoma development according to the BDNF polymorphism remains unclear.

Quantitative brain-derived neurotrophic factor lateral flow assay for point-of-care detection of glaucoma

“…There is strong evidence proving changes in BDNF are involved in the early pathogenic stages of glaucoma including retinal ganglion cell apoptosis and axonal dystrophy 51 . A decrease of retrograde transportation of BDNF from brain to retina has been established in several animal models of glaucoma [52][53][54] , whilst exogenous BDNF has been shown to be neuroprotective to injured RGCs 55 . Several clinical studies have identified significantly reduced serum levels of BDNF in glaucoma patients compared with healthy volunteers [56][57][58]…”

Risk Factors for Retinal Ganglion Cell Distress in Glaucoma and Neuroprotective Potential Intervention

“…Among NTs, BDNF seems to be particularly crucial for RGC survival because, in addition to being produced by the RGCs themselves and by retinal astrocytes, it also has a role in retrograde axonal transport (from the brain to the retina) [ 51 , 52 ]. Indeed, BDNF, once produced by the superior colliculus or by the lateral geniculate nucleus, binds to the TrkB receptor in order to reach the cell bodies by way of retrograde transport within the microsomal vesicles [ 53 ].…”