Intranasal BDNF administration promotes visual function recovery in adult amblyopic rats

Amblyopia is the most common cause of visual impairment in one eye, with a prevalence of 1e5% in theworld population. While amblyopia can be efficiently treated in children, it becomes irreversible in adults,due to the decline in neural plasticity past the end of the visual cortex critical period. Accordingly, nopharmacological approaches are available to rescue visual functions in adult amblyopic subjects. We reportthat non-invasive intranasal infusion of BDNF increased levels of this neurotrophic factor in V1 and induceda recovery of visual acuity, ocular dominance and visual depth perception in adult amblyopic rats, both inreverse-occluded animals and in those with unrestricted binocular sight. Visual recovery was long-lasting,and was prevented by pharmacological blockade of TrkB signaling in the visual cortex. These results un-derscore the possibility to replace invasive BDNF central administration with a safe procedure of potentialinterest in a number of currently still cureless central nervous system pathologies