Comparison of the effects of high and low concentrations of the separated VISCUM ALBUM L. lectins and of the plain mistletoe plant preparation (Isorel) on the growth of normal and tumor cells in vitro

Journal/Book: Periodicum Biologorum 97 (1), 61-67. 1995;

Abstract: Background and purpose: Due to their cytotoxic, but notimmunosuppressive effects various mistletoe (Viscum album L.)preparations are used for the therapy of human diseases, particularlycancer. However, nature of the active principle of mistletoe is stilluncertain, while it is supposed that the toxic mistletoe lectins couldbe the main active component of the plant extracts. The aim of thisstudy was to compare the effects of the mistletoe lectins with themistletoe preparation Isorel and its different MW components (preparedby membrane ultrafiltration) on the growth of murine melanoma cells andConA stimulated lymphocytes in vitro. Material and methods: The effectswere determined for high (2 mug proteins/ml) concentration, which allowsthe maximal efficiency of the mistletoe lectins in vitro, and for lowconcentration (0.2 ng proteins/ml), which corresponds better to the invivo applied doses of the mistletoe preparations. The effects of thesamples added to the culture medium were determined according to theirinfluence on the intensity of 3H-thymidine incorporation. Results: Theresults obtained indicate that the effects of used at higher dose couldbe result of the unspecified toxic activity of the mistletoe lectins. Onthe contrary if used at lower concentration, Viscum album preparationshowed mainly growth inhibiting effect on tumor cells, that was theresult of the activity of the low MW components, but not the lectins.Conclusions: Hence, it is supposed that the beneficial therapeuticeffects of the Viscum album preparation might result from the combinedbiological activity of the high and the low MW components, since none ofthem separately was as efficient as the entire preparation. While thehigh MW cytotoxic components of the preparation might mainly bemistletoe lectins, the nature of the low MW active components is stillunknown.

Keyword(s): Medical:melanoma

Zurück | Weiter