Zedoary oil (Ezhu You) inhibits proliferation of AGS cells
1 Institute of Digestive Disease, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, 725 South Wanping Road, XuHui District, Shanghai 200032, PR China
2 Institute of Materia Medica, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Zhangjiang Hi-tech Park, Shanghai 201203, PR China
3 Shanghai Key Laboratory of Complex Prescription, 1200 Cailun Road, Zhangjiang Hi-tech Park, Shanghai 201203, PR China
4 Chinese Medicine Hospital of Shanxi Province, Taiyuan, Shanxi Province 030012, PR China
Chinese Medicine 2013, 8:13 doi:10.1186/1749-8546-8-13Published: 28 June 2013
Zedoary (Curcumae Rhizoma, Ezhu), a Chinese medicinal herb, has been reported to show anticancer activity. This study aims to investigate the effect of zedoary oil (Ezhu You) on the proliferation of AGS cells which is one gastric cancer cell line.
The main ingredients of the herb were detected by GC-MS for herbal quality control. Cell viability was measured by MTT assay and cell proliferation was investigated by immunocytochemical staining for proliferating cell nuclear antigen (PCNA) protein. In addition, the cell cycle distributions were detected by flow cytometry with propidium iodine (PI) staining and the apoptosis rates were evaluated by flow cytometry with annexin V/PI double-staining. The morphological changes associated with apoptosis were observed by Hoechst 33342/PI double-staining. Protein expression was determined by western blot analysis.
The main ingredients of the herb, including curzerene (26.45%), eucalyptol (12.04%), curcumol (9.04%), pyridine (7.97%), germacrone (7.89%), β-elemene (7.36%), τ-elemene (4.11%) and 28 other ingredients, including curdione, were consistent with the chemical profiles of zedoary. Zedoary oil significantly decreased the cell viability of AGS cells (P < 0.01) and MGC 803 cells (P < 0.01), and the inhibitory effects were attenuated by elevated concentrations of FBS. At high concentrations (≥90 μg/mL), zedoary oil killed GES-1 cells. At low concentrations (≤60 μg/mL), zedoary oil was less inhibitory toward normal gastric epithelial cells than gastric cancer cell lines. In AGS cells, zedoary oil inhibited cell proliferation in a dose- and time-dependent manner, with decreased PCNA protein expression in the zedoary oil-treated cells, and arrested the cell cycle at S, G2/M and G0/G1 stages after treatment for 6–48 h. At concentrations of 30, 60 and 90 μg/mL, which resulted in significant inhibition of proliferation and cell cycle arrest, zedoary oil induced cell apoptosis. In addition, Hoechst 33342/PI double-staining confirmed the morphological characteristics of cell apoptosis at 24 h. Zedoary oil upregulated the ratio of Bax/Bcl-2 protein expression (P < 0.01).
Zedoary oil inhibited AGS cell proliferation through cell cycle arrest and cell apoptosis promotion, which were related to Bax/Bcl-2 protein expression.