High performance liquid chromatographic analysis and anticancer potential of Oplopanax horridus: comparison of stem and berry extracts

Abstract

Oplopanax horridus or devil's club is a herbal medicine distributed in North America. The constituents and pharmacological activities of O. horridus (OPH) are largely unknown. In this study, we assayed OPH stem and berry extracts using high performance liquid chromatography (HPLC). The anticancer potentials of extracts on different human cancer cell lines (SW-480, HCT-116, HT-29, MCF-7 and NSCLC) were determined by MTS method. The effect of stem extract on cancer cell cycle, expression of cyclin A, and apoptosis were assayed using flow cytometry. HPLC data showed that the composition of OPH stem extract is more complicated than the berry extract. The wavelength of maximum absorption of the major constituent in stem and berry is 196.0 nm and 201.9 nm, respectively. Compared to the berry extract, the stem extract showed significant potent antiproliferative effect on all the studied cell lines. The stem extract at 0.1 mg/ml arrested cancer cells in S- and G2/M-phases, and significantly induced expression of cyclin A. After treatment with 0.1 mg/ml of stem extract for 72 h, apoptotic cells were increased to 45.2%, while control was 9.6%. The cell cycle arrest and induction of apoptosis may play a critical role in cancer chemoprevention by Oplopanax horridus stem extract.

Fig. 1

HPLC analysis of Oplopanax horridus stem and berry extracts. (A) HPLC chromatogram of stem extract recorded in 202 nm. (B) HPLC chromatogram of berry extract recorded in 202 nm. (C) UV spectra (190–400 nm) of peaks 1–14. Peak numbers are shown in (A) and (B).

Fig. 2

Effects of Oplopanax horridus stem and berry extracts on proliferation of different human cancer cell lines assayed by MTS method. Cell line used includes colorectal cancer (SW-480, HCT-116, HT-29), breast cancer (MCF-7) and non-small cell lung cancer cells (NSCLC). Cells were treated with 0.1–1 mg/ml of extract for 72 h. Since SW-480 and HCT-116 cells are more sensitive to stem extract, additional concentrations 0.01 and 0.05 mg/ml were also evaluated. * P<0.05; and ** P<0.01 vs. control (100%).

Fig. 3

Cell cycle analysis using flow cytometry after propidium iodide (PI) staining. SW-480 cells were treated with 0.05 and 0.1 mg/ml of Oplopanax horridus stem extract for 24, 48 and 72 h.

Fig. 4

Cyclin A analysis of SW-480 cells using flow cytometry. After treatment with 0.1 mg/ml of Oplopanax horridus stem extract for 24, 48 and 72 h, cells were stained with cyclin A-FITC and propidium iodide (PI). The percentage of cyclin A positive cells is shown in the gate.

Fig. 5

Apoptosis assay using flow cytometry after annexin V-FITC and propidium iodide (PI) staining. SW-480 cells were treated with 0.05 and 0.1 mg/ml of Oplopanax horridus stem extract for 24, 48 and 72 h.