ACHE and Alzheimer disease: Huperzine A (Hup-A), an approved anti-AD drug in China, has been found to act on multiple AD targets, such as inhibiting AChE, inhibiting N-methyl-D-aspartate (NMDA) receptor, protecting neuronal cells against Aβ, free radicals and hypoxia-ischemia induced injury and so on [9–12].