Neuroprotective effects of total alkaloids fraction of Huperzia serrata on scopolamine‐induced neurodegenerative animals

Abstract Huperzia serrata contains Huperzine A (HupA)—an alkaloid used to treat cognitive dysfunction. In this study, we used the total alkaloids (HsAE) to investigate their potential in managing cognitive impairment in comparison with HupA. The antioxidant activity was measured by DPPH assay. In the cellular study, the cell viability and level of ACh of SH‐SY5Y cells were evaluated after pretreated with HsAE and scopolamine. For in vivo assay, mice were pre‐treated with HsAE, and HupA and undergone scopolamine injection for cognitive impairment. The behavioral tests including the Y‐maze and Morris water maze test and the AChE activity, the SOD, CAT, MDA level in the hippocampus and cortex were evaluated. HsAE showed significant scavenging properties on DPPH radicals. HsAE was not toxic to SH‐SY5Y cells, and can rescue these cells upon scopolamine treatment. Intriguingly, HsAE showed the neuroprotection against scopolamine‐induced amnesia in mice. Moreover, HsAE decreased AChE activity, MDA level, increased antioxidative enzyme activity in the hippocampus as well as cortex of mice, which was relatively better than that of HupA. These findings suggested that HsAE may significantly protect the neurons of mice with scopolamine—induced memory impairment connected to AChE depletion and oxidative stress.