BDNF and Alzheimer disease: When considering that synaptic plasticity and memory functions are impaired in the brains of AD patients [82], and that GCs enhance memory consolidation in which BDNF has essential roles as a synaptic modulator [83,84], these results, including ours, suggest that an “appropriate dose” of GCs may play a beneficial role for patients with HD and AD by promoting neuronal survival and memory consolidation through the enhanced neuronal transport of BDNF.