BDNF and Alzheimer disease: Recently, Aleksandra (2020) in a review paper, introduced C-reactive protein (CRP), microRNAs (miRNAs), paraoxonase 1 (PON-1), glycogen synthase kinase 3β (GSK-3β), phosphoinositide 3-kinases (PI3K), amylin, dopamine, gamma-glutamyl transferase (GGT), various growth factors (NGF, TGF, and BDNF), and homocysteine, as the main actors in neurodegeneration in AD, mild cognitive impairment, and dementia [52].