ACHE and early-onset autosomal dominant Alzheimer disease: Of these, huperzine A (Hup A), isolated from the Chinese folk medicinal herb Qian Ceng Ta [whole plant of Huperzia serrata (Thunb.ex Murray) Trev.], is a promising agent to treat Alzheimer’s disease with highly specific and potent inhibitory activity against acetylcholinesterase (AChE) [9].