Erinacerins, Novel Glioma Inhibitors from Hericium erinaceus, Induce Apoptosis of U87 Cells through Bax/Capase-2 Pathway

Background: Glioma is the most common tumor of the central nervous system. Hericium erinaceus, which has been reported to have a variety of pharmacological activities, is a widely used Traditional Chinese Medicine (TCM), and also a kind of delicious food accepted by the public. Methods and Results: In this study, two new natural products, compounds 1 and 2, were isolated and identified from Hericium erinaceus. They were named erinacerin O and erinacerin P, respectively, after the structural identification, and their effects on human glioma cell line U87 were evaluated. Erinacerin P (2) exhibited obvious cytotoxicity on human glioma cell line U87. The IC50 value of 2 was 19.32μg/mL. The results showed that the apoptosis of U87 cells treated with 2 increased and the morphology of U87 cells altered significantly. Flow cytometry experiment showed that 2 could significantly increase the apoptosis rate of U87 cells and reduce DNA replication. Western blot results suggested the Bax/capase-3 pathway was involved in the U87 cell apoptosis induced by 2. Conclusion: Erinacerin O and Erinacerin P are novel compounds obtained from Hericium erinaceus and Erinacerin P could be a potential novel glioma inhibitor.