Pharmacological effect of prohibited combination pair Panax ginseng and Veratrum nigrum on colorectal metastasis in vitro and in vivo.

BACKGROUND

The pharmacological effect derived from herb-herb interaction is important to constitute the prescription especially in traditional oriental medicine. The relationship of two medicinal herbs is called "couplet medicinals" which is used in pair for the purpose of enhancing the therapeutic effect, reducing the toxic effect or the adverse effect. The "Eighteen Incompatible Medicaments" constitute one of the contents in the incompatibility of traditional oriental drugs in a prescription. Among the "Eighteen Incompatible Medicaments", the roots and rhizomes of Veratrum nigrum (VN), is incompatible with the roots and rhizomes of Panax ginseng (PG). However, definite evidences of adverse effect by these combinations has yet to be reported.

METHODS

The aim of the present study was to investigate the effects of ethanol extracts of PG, VN, and their combination (P + V) on the metastatic ability of colorectal cancer (CRC) cells using WST assay, flow cytometry, western blot analysis, real-time RT-PCR, immunofluorescence, migration assay, invasion assay, zymography, and an in vivo experiment with a lung-metastasis mouse model.

RESULTS

The PG extract decreased cell proliferation by inducing cell cycle arrest and apoptosis of CRC cells. In addition, PG inhibited metastatic abilities of CRC cells including Epithelial-Mesenchymal Transition, migration, and invasion. Additionally, the PG extract suppressed lung metastasis of the CRC cells in the mouse model. However, the P + V extract exhibited weaker anti-proliferative and anti-metastatic effects than PG alone.

CONCLUSIONS

Based on these results, the P + V couplet medicinal attenuates the anti-metastatic effects of PG, both in vitro and in vivo.