Deglucose chikusetsusaponin IVa isolated from Rhizoma Panacis Majoris induces apoptosis in human HepG2 hepatoma cells

Abstract

Deglucose chikusetsusaponin IVa (DCIVa), isolated from Rhizoma Panacis Majoris, a widely used traditional Chinese medicine, is a type of oleanane triterpenoids. Various previous studies have demonstrated that oleanane triterpenoids exhibit cytotoxic activity against various types of cancer cells. However, whether DCIVa exerts an antitumor effect remains to be elucidated. The present study aimed to assess the effect of DCIVa on cancer cells using the HepG2 hepatocellular carcinoma cell line and determine the underlying mechanism. Using an MTT assay, it was demonstrated that DCIVa inhibited cell growth and viability in a dose-and time-dependent manner. Typical apoptotic features, including chromatin condensation and margination at the nuclear periphery, and apoptotic body formation were induced by DCIVa and were detected by transmission electron microscopy. In addition, nuclear condensation and fragmentation were also observed by Hoechst 33258 staining. Furthermore, flow cytometric analysis revealed that DCIVa increased cell apoptosis and G2/M cell cycle arrest dose-dependently. Western blot analysis further demonstrated that DCIVa upregulated the expression of the pro-apoptotic protein, Bax, and downregulated the expression of the anti-apoptotic protein, Bcl-2. In conclusion, the present study demonstrated for the first time, to the best of our knowledge, that DCIVa exerts potent cytotoxic effects on HepG2 cells through induction of cell apoptosis and cell cycle arrest, and may be utilized as a potential anticancer agent.