Preparative isolation of graphislactone A from the fruits of Sinopodophyllum hexandrum and its antitumor action mechanism / 中草药

ABSTRACT

Objective To establish the preparative isolation technique of grahislactone A from the fruits of Sinopodophyllum hexandrum, and to investigate the action mechanism for apoptosis induction of graphislactone A in MCF-7/ADR cell line (human breast adencarcinoma cell line). Methods The fruits of S. hexandrum were extracted under ultrasound by EtOAc. Graphislactone A was enriched by silica gel column chromatography, and then purified by recrystallization. The cytotoxic activities of graphislactone A were tested against MCF-7 and MCF-7/ADR cell lines by MTT. The apoptosis of MCF-7/ADR cell line was evaluated by flow cytometry. RT-PCR was used to detect the expression of apoptosis-related genes in MCF-7/ADR cell line. Expression of P-gp in MCF-7/ADR cell line was investigated by western blotting. Results Graphislactone A was isolated from the fruits of S. hexandrum, which showed the potent cytotoxic activities against MCF-7 and MCF-7/ADR cell lines, with IC50 values of 2.38 and 9.35 μmol/L, respectively. With the increased dose of graphislactone A, the expression levels of p53, bax, caspase-3 genes were up-regulated, while bcl-2 and P-gp down-regulated in MCF-7/ADR cell line. Conclusion Graphislactone A as phenolic compoundswas firstly found in higher plants. The preparative isolation has the advantages of high-efficiency, high sample recovery, and high-purity compared with etoposide. Graphislactone A showed strong cytotoxic activities and apoptosis induction action in MCF-7 and MCF-7/ADR cell line.