Viscum album L. - Loranthaceae - mistletoe, European mistletoe, Weißbeerige Mistel, Laubholz-Mistel

Dioecious, muchbranched, semiparasitic evergreen shrub, native to Europe, temperate Asia; branches pendulous, up to 1m long; leaves simple, thick, leathery, yellow-green; flowers inconspicuous, pale yellow; berries two-seeded, white, with sticky pulp.

„Several subspecies are commonly accepted. They differ in fruit colour, leaf shape and size, and most obviously in the host trees utilised.“ https://en.wikipedia.org/wiki/Viscum_album

Using the purified toxic proteins from VAL [Viscum album], such as the d-galactose-speciflc lectin I (ML I), the N-acetyl-d-galactosamine-specific ML II and ML III, it became obvious that the killing of cultured human lymphocytes and blast cells „… was mediated by the induction of apoptosis, as measured by the appearance of a hypodiploid DNA peak using flow cytometry. ML III was the most effective to induce apoptosis, followed by ML II and ML I, while the viscotoxins and oligosaccharides from VAL did not.“
[Induction of apoptosis in human lymphocytes treated with Viscum album L. is mediated by the mistletoe lectins., Büssing, A., Suzart, K., Bergmann, J., Pfüller, U., Schietzel, M., Schweizer, K., Cancer letters, 99(1), 1996, 59-72]

„Biologically active VAL [Viscum album] compounds, and thus cytotoxicity, are dependent on the manufacturing process, host tree, and time of harvest. Although the mistletoe lectin (ML) content of VAL extracts strongly correlated with their apoptosis-inducing properties, the presence of these proteins will not guarantee its biological activity, indicating the involvement of other components which may modulate ML cytotoxicity.“
[Apoptosis-inducing properties of Viscum album L. extracts from different host trees, correlate with their content of toxic mistletoe lectins., Büssing, A., Schietzel, M., Anticancer research, 19(1A), 1998, 23-28]

The fresh or dried herb or leaves only are used to make products for cytostatic, non-specific immune stimulation injections. The plant contains lectins (0.1%, mistle lectin I-III), each of which with numerous isolectins.
„Of special interest are up to 0.1% viscotoxins, polypeptides (viscotoxins A, B, P) composed of 46 amino acids.
Some clinical studies showed significant benefits in the treatment of malignant metastatic tumors.“
[Medicinal Plants of the World. Ben-Erik Van Wyk and Michael Wink, Pretoria 2004, 342]

„Single Viscum album L. extracts containing only solubilised triterpene acids (TT) or lectins (viscum) inhibited cell proliferation and induced apoptosis in a dose-dependent manner in vitro and ex vivo. The combination of viscum and TT extracts (viscumTT) enhanced the induction of apoptosis synergistically. The experiments demonstrated that all three extracts are able to induce apoptosis via caspase-8 and -9 dependent pathways with down-regulation of members of the inhibitor of apoptosis and Bcl-2 families of proteins. Finally, the acute myeloid leukaemia mouse model experiment confirmed the therapeutic effectiveness of viscumTT-treatment resulting in significant tumour weight reduction, comparable to the effect in cytarabine-treated mice.“
[A Natural Combination Extract of Viscum album L. Containing Both Triterpene Acids and Lectins Is Highly Effective against AML In Vivo., Delebinski, C.I., Twardziok, M., Kleinsimon, S., Hoff, F., Mulsow, K., Rolff, J., Seifert, G., PloS one, 10(8), 2015, e0133892] http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0133892

viscum_album.jpg
Thomé,O.W., Flora von Deutschland Österreich und der Schweiz, Tafeln, vol.3 t.460 (1885)
http://plantgenera.org/species.php?id_species=1066383

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Viscum album (s. str.), Wien (Austria) © Rolf Marschner (2022) www.botanische-spaziergaenge.at