The alkaloids in STR, CR, and PCC can affect other factors related with AD: fangchinoline has a protective effect on cyanide-induced neurotoxicity [49,50]; coptisine ameliorates cognitive impairment by inhibiting indoleamine 2,3-dioxygenase [51]; and berberine shows multiple activities to relieve symptoms of AD [52]. This evidence concerns the gene IDO2 and Alzheimer disease.