BDNF and neurodegenerative disease: A large body of evidences indicates that reduced expression of neurotrophins and changes in the level of their receptors can lead to dysregulation of neuronal function, and neuronal death can lead to the development of neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease (Scaper 2008; Bruno et al. 2009; Calissano et al. 2010).