VEGFA and neurodegenerative disease: In this case, VEGF plays an important role: on the one hand, it performs a neuroprotective function in PD by acting on dopaminergic neurons [245]; on the other hand, an excess of VEGF leads to an increase in vascular permeability, a violation of the integrity of the BBB, which can become the main pathogenetic factor in various neurodegenerative diseases, including PD [286].