A heat-stable extract from Mucuna stimulates the differentiation of bone marrow cells into dendritic cells and induces apoptosis in cancer cells.

Pine cone extract is known to induce differentiation of human mononuclear cells into dendritic cells (DCs) and also to induce apoptosis in human cancer cells. In the present study, we screened edible plants that contain components with biological activities similar to or more potent than those of pine cone extract. We found that Mucuna (Mucuna pruviens var. utilis) contains a DC differentiation/maturation-inducing activity and a component that induces apoptosis in human cancer cell lines. Mucuna extract specifically stimulated differentiation of BM cells to immature DCs. Marked production of IL-6 was observed by sequential treatment with at least 10 µg/mL of Mucuna extract followed by LPS. The sequential treatment with Mucuna extract followed by LPS produced a much higher ratio of IL-12 to IL-6 and a lower ratio of TNF-α to IL-6 than that obtained by sequential treatment with a medicinal mushroom Phellinus linteus extract and then LPS. The DC differentiation/maturation activity and the component inducing apoptosis in cancer cells were separable by column chromatography.

Dendritic cell differentiation and tumor cell apoptosis induced by components of a poly-phenylpropanoid polysaccharide complex.

BACKGROUND: As part of the indigenous folk medicine in Japan, aqueous extracts of pine cones have been used for over a century to treat cancer and other illnesses and references to their use can be found in ancient Greek literature. However, the mechanisms by which such extracts work are largely unknown. MATERIALS AND METHODS: Murine bone marrow (BM)-derived dendritic cells (DCs) and human monocyte U937 cells were treated in vitro with an extract prepared from pine cones (termed poly-phenylpropanoid polysaccharide complex, PPC). RESULTS: The components of the PPC were separated into different molecular weight fractions with distinct biological activities. One fraction, consisting of relatively high molecular weight material, was found to induce the differentiation of murine BM cells into immature DC, as well as the maturation of immature DCs into mature DCs. A second fraction, consisting of low molecular weight material, was found to inhibit the in vitro growth of the U937 cells and two other human cancer cell lines. The inhibition of tumor cell growth was found to be associated with the generation of reactive oxygen species (ROS) and the induction of a mitochondria-dependent apoptotic pathway. CONCLUSION: The effects on dendritic cells and the inhibition of tumor growth, if they occur to a significant level in vivo, could help explain the apparent usefulness of PPC in the treatment of cancer.