BDNF and glaucoma: Multiple in vivo studies have suggested that the deficits of BDNF expression mark the RGC damage in glaucoma, and its interrupted axonal transport has been implicated in the progressive development of optic neuropathy in experimental models of glaucoma (Gupta et al., 2014; Feng et al., 2016; Osborne et al., 2018; Chitranshi et al., 2019; Wójcik-Gryciuk et al., 2020; Conti et al., 2021; Lazzara et al., 2021).