Mistletoe Preparations as an Option for Treatment of Equine Sarcoids – Results of an In vitro Investigation on Cell Proliferation in 2D And 3D Design - Abstract
It is difficult to deal with the most common skin tumor in horses: the equine sarcoid. Its recurrence rate is very high and no single universally effective treatment without serious side effects is yet available.
Aqueous fermented mistletoe extracts of eight different host trees (pine tree, fir tree, hawthorn, apple tree, poplar tree, lime tree, oak tree, willow tree) were tested for their impact on the proliferation of the equine sarcoid cell line E42/02 in a 2D and 3D design.
All mistletoe preparations inhibit the proliferation of the equine sarcoid cells in vitro. The order of the IC50 concentrations was in accordance with the content of mistletoe lectin of the respective Viscum album preparations. The extract from the pine tree (Pini) showed the lowest potency to reduce the cell growth. The strongest inhibition of cell proliferation was obtained with the mistletoe extract of the willow tree (Salicis) with an IC50 concentration of 11 µg/ml in the 2D Alamar Blue assay and 1.2 µg/ml in the 3D Soft Agar assay. In addition to the high content of mistletoe lectin in the extracts from the mistletoe growing on
willow tree, further components need to be taken into consideration to assess the full potential, such as the various acids exhibiting anti-tumoral action as well as the anti-phlogistic salicin.
These results indicate that the treatment with mistletoe preparations presents an effective therapy for horses suffering from equine sarcoids. The preparation from the willow tree mistletoe offers both cytotoxic and anti-inflammatory activity which awaits to be proofen in an in vivo design.