PDE4B and Alzheimer disease: Based on the prediction results of machine learning, fangchinoline was found to interact with 11 AD-related targets (ACHE, BCHE, APP, PTGS2, PDE4B, CHRNA7, GABRG1, SIGMAR1, HTR1A, HTR3A and HTR6) and dauricine was also found to interact with 11 AD-related targets (ACHE, BCHE, APP, PTGS2, PDE4B, ALOX12, GABRG1, SIGMAR1, HTR1A, HTR3A and HTR6) (Table 5).