Viscumalbum L. homeopathic mother tinctures: metabolome and antitumor activity

ABSTRACT

Viscum album L. is a semi-parasitic plant with antitumor activity attributed to theaqueous extracts. However, European V. album ethanolic extracts (VAE) have also demonstrated invitro activity in tumor models. Aims: Evaluate the metabolic profiles of fifty VAE harvested duringsummer and winter seasons and their antitumor activity through 2D and 3D models. Methodology:VAEwerepreparedbymacerationfromV.albumsubsp.albumgrowingonMalus domestica,Quercus sp.and Ulmus sp.; V. album subsp. austriacum from Pinus sylvestris; V. album subsp. abietis from Abies alba.Chemical analyses were performed through liquid chromatography coupled with high resolutionmass spectrometry and Partial Least Squares Discriminant Analysis (PLS-DA) was performed in theMetaboanalyst 4.0. The antitumor potential of the selected VAE was evaluated in 2D and 3D models(MDA-MB-231 cancer cells) by MTT, crystal violet and glycolytic pathway analysis. Results anddiscussion:Thefirst3principalcomponentsinPLS-DAexplained60%and40%ofdatavariationin positive andnegativemodesrespectively.Threegroupswereformedandshowedchemicalsimilarityamong V. album subspecies. The compounds responsible for group separation were tentativelyidentifiedaspinobankasinornaringenin hexoside;isorhamnetin-3-hexoside,meglutolanddifferent aminoacids.ThesummerVAEat0.5%v/vinducedhighercytotoxicdamagethanthewinterpreparations, and Abies alba and Quercus sp. VAE promoted 49% and 42% reduction of tumorviability in 3D model (72h incubation), respectively. MDA-MB-231 glycolytic pathway in 2D modelshowed a decrease in the glucose consumption and extracellular lactate production. Also, PFK (6-phosphofructo-1-kinase)andPK(Pyruvatekinase)activitieswereinhibitedbyAbiesalbaandQuercus sp. VAE at 48h of incubation. Conclusion: VAE extracts showed different metabolomes andthe glycolytic pathway should be an important target involved in the inhibition of tumor growth bytheseextracts