APP and Alzheimer disease: For the purpose of studying the neuroprotective effects of BBMH on AD, three kinds of AD model mice including double transgenic APP/PS1 AD mice, Gal-Alu AD mice induced by the intraperitoneal injection of d-galactose combined with the intragastric administration of aluminum trichloride, and Alu AD mice induced by stereotactic brain injection of aluminum trichloride were prepared first.