Divalent or multivalent molecules often show enhanced biological activity relative to the simple monomeric units. Here we present enzymatically and chemically prepared dimers of the flavonolignans silybin and 2,3-dehydrosilybin. Their electrochemical behavior was studied by in situ and ex situ square wave voltammetry. The oxidation of monomers and dimers was similar, but adsorption onto the electrode and cell surfaces was different. A 1,1-diphenyl-2-picrylhydrazyl (DPPH) and an inhibition of microsomal lipoperoxidation assay were performed with same trend of results for silybin and 2,3-dehydrosilybin dimers. Silybin dimer showed better activity than the monomer, while on the contrary 2,3-dehydrosilybin dimer presented weaker antioxidant/antilipoperoxidant activity than its monomer. Cytotoxicity was evaluated on human umbilical vein endothelial cells, normal human adult keratinocytes, mouse fibroblasts (BALB/c 3T3) and human liver hepatocellular carcinoma cell line (HepG2). Silybin dimer was more cytotoxic than the parent compound and in the case of 2,3-dehydrosilybin its dimer showed weaker cytotoxicity than the monomer.

Department of Medical Chemistry and Biochemistry Faculty of Medicine and Dentistry Palacký University Hněvotínská 3 CZ 775 15 Olomouc Czech Republic

Institute of Microbiology Academy of Sciences of the Czech Republic Vídeňská 1083 CZ 142 20 Prague 4 Czech Republic

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Gazak R., Walterova D., Kren V. Silybin and silymarin—New and emerging applications in medicine. Curr. Med. Chem. 2007;14:315–338. doi: 10.2174/092986707779941159. PubMed DOI

Kren V., Gazak R., Purchartova K., Marhol P., Biedermann D., Sedmera P. Chemoenzymatic preparative separation of silybins A and B. J. Mol. Catal. B: Enzymat. 2009;61:247–251.

Gazak R., Trouillas P., Biedermann D., Fuksova K., Marhol P., Kuzma M., Kren V. Base-catalyzed oxidation of silybin and isosilybin into 2,3-dehydro derivatives. Tetrahedron Lett. 2013;54:315–317. doi: 10.1016/j.tetlet.2012.11.049. DOI

Huber A., Thongphasuk P., Erben G., Lehmann W.D., Tuma S., Stremmel W., Chamulitrat W. Significantly greater antioxidant anticancer activities of 2,3-dehydrosilybin than silybin. Biochim. Biophys. Acta. 2008;1780:837–847. PubMed

Thongphasuk P., Stremmel W., Chamulitrat W. 2,3-dehydrosilybin is a better DNA topoisomerase I inhibitor than its parental silybin. Chemotherapy. 2009;55:42–48. doi: 10.1159/000175466. PubMed DOI

Gazak R., Svobodova A., Psotova J., Sedmera P., Prikrylova V., Walterova D., Kren V. Oxidised derivatives of silybin and their antiradical and antioxidant activity. Bioorg. Med. Chem. 2004;12:5677–5687. doi: 10.1016/j.bmc.2004.07.064. PubMed DOI

Zatloukalova M., Kren V., Gazak R., Kubala M., Trouillas P., Ulrichova J., Vacek J. Electrochemical investigation of flavonolignans and study of their interactions with DNA in the presence of Cu(II) Bioelectrochemistry. 2011;82:117–124. doi: 10.1016/j.bioelechem.2011.06.005. PubMed DOI

Gazak R., Sedmera P., Vrbacky M., Vostalova J., Drahota Z., Marhol P., Walterova D., Kren V. Molecular mechanisms of silybin and 2,3-dehydrosilybin antiradical activity—Role of individual hydroxyl groups. Free Radic. Biol. Med. 2009;46:745–758. doi: 10.1016/j.freeradbiomed.2008.11.016. PubMed DOI

Gazak R., Purchartova K., Marhol P., Zivna L., Sedmera P., Valentova K., Kato N., Matsumura H., Kaihatsu K., Kren V. Antioxidant and antiviral activities of silybin fatty acid conjugates. Eur. J. Med. Chem. 2010;45:1059–1067. doi: 10.1016/j.ejmech.2009.11.056. PubMed DOI

Theodosiou E., Katsoura M.H., Loutrari H., Purchartova K., Kren V., Kolisis F.N., Stamatis H. Enzymatic preparation of acylated derivatives of silybin in organic and ionic liquid media and evaluation of their antitumor proliferative activity. Biocatal. Biotrans. 2009;27:161–169.

Theodosiou E., Loutrari H., Stamatis H., Roussos C., Kolisis F.N. Biocatalytic synthesis and antitumor activities of novel silybin acylated derivatives with dicarboxylic acids. New Biotechnol. 2011;28:342–348. doi: 10.1016/j.nbt.2011.01.006. PubMed DOI

Monti D., Gazak R., Marhol P., Biedermann D., Purchartova K., Fedrigo M., Riva S., Kren V. Enzymatic kinetic resolution of silybin diastereoisomers. J. Nat. Prod. 2010;73:613–629. doi: 10.1021/np900758d. PubMed DOI

Chen X.Y., Zenger K., Lupp A., Kling B., Heilmann J., Fleck C., Kraus B., Decker M. Tacrine-silibinin codrug shows neuro- and hepato protective effects in vitro and pro-cognitive and hepatoprotective effects in vivo. J. Med. Chem. 2012;55:5231–5242. doi: 10.1021/jm300246n. PubMed DOI

Zarrelli A., Romanucci V., Greca M.D., de Napoli L., Previtera L., di Fabio G. New silybin scaffold for chemical diversification: Synthesis of novel 23-phosphodiester silybin conjugates. Synlett. 2013;24:45–48.

Gazak R., Sedmera P., Marzorati M., Riva S., Kren V. Laccase-mediated dimerization of the flavonolignan silybin. J. Mol. Catal. B. 2008;50:87–92. doi: 10.1016/j.molcatb.2007.09.005. DOI

Trouillas P., Marsal P., Svobodova A., Vostalova J., Gazak R., Hrbac J., Sedmera P., Kren V., Lazzaroni R., Duroux J.L., et al. Mechanism of the antioxidant action of silybin and 2,3-dehydrosilybin flavonolignans: A joint experimental and theoretical study. J. Phys. Chem. A. 2008;112:1054–1063. doi: 10.1021/jp075814h. PubMed DOI

Pliskova M., Vondracek J., Kren V., Gazak R., Sedmera P., Walterova D., Psotova J., Simanek V., Machala M. Effects of silymarin flavonolignans and synthetic silybin derivatives on estrogen and aryl hydrocarbon receptor activation. Toxicology. 2005;215:80–89. doi: 10.1016/j.tox.2005.06.020. PubMed DOI

Berube G. Natural and synthetic biologically active dimeric molecules: Anticancer agents, anti-hiv agents, steroid derivatives and opioid antagonists. Curr. Med. Chem. 2006;13:131–154. doi: 10.2174/092986706775197908. PubMed DOI

Mott B.T., Tripathi A., Siegler M.A., Moore C.D., Sullivan D.J., Posner G.H. Synthesis and antimalarial efficacy of two-carbon-linked, artemisinin-derived trioxane dimers in combination with known antimalarial drugs. J. Med. Chem. 2013;56:2630–2641. doi: 10.1021/jm400058j. PubMed DOI PMC

Jenett-Siems K., Kohler I., Kraft C., Pertz H.H., Kren V., Fiserova A., Kuzma M., Ulrichova J., Bienzle U., Eich E. In vitro antiplasmodial activities of semisynthetic N,N'-spacer-linked oligomeric ergolines. Bioorg. Med. Chem. 2004;12:817–824. doi: 10.1016/j.bmc.2003.10.035. PubMed DOI

Chan K.F., Zhao Y.Z., Burkett B.A., Wong I.L.K., Chow L.M.C., Chan T.H. Flavonoid dimers as bivalent modulators for P-glycoprotein-based multidrug resistance: Synthetic apigenin homodimers linked with defined-length poly(ethylene glycol) spacers increase drug retention and enhance chemosensitivity in resistant cancer cells. J. Med. Chem. 2006;49:6742–6759. doi: 10.1021/jm060593+. PubMed DOI

Dolle C., Magrone P., Riva S., Ambrosi M., Fratini E., Peruzzi N., Lo Nostro P. Symmetric and asymmetric bolaamphiphiles from ascorbic acid. J. Phys. Chem. B. 2011;115:11638–11649. PubMed

Chebil L., Humeau C., Falcimaigne A., Engasser J.M., Ghoul M. Enzymatic acylation of flavonoids. Process Biochem. 2006;41:2237–2251.

Magrone P., Cavallo F., Panzeri W., Passarella D., Riva S. Exploiting enzymatic regioselectivity: A facile methodology for the synthesis of polyhydroxylated hybrid compounds. Org. Biomol. Chem. 2010;8:5583–5590. doi: 10.1039/c0ob00304b. PubMed DOI

Zatloukalova M., Enache T.A., Kren V., Ulrichova J., Vacek J., Oliveira-Brett A.M. Effect of 3-O-galloyl substitution on the electrochemical oxidation of quercetin and silybin galloyl esters at glassy carbon electrode. Electroanalysis. 2013;25:1621–1627. doi: 10.1002/elan.201300102. DOI

Vacek J., Zatloukalova M., Desmier T., Nezhodova V., Hrbac J., Kubala M., Kren V., Ulrichova J., Trouillas P. Antioxidant, metal-binding and DNA-damaging properties of flavonolignans: A joint experimental and computational highlight based on 7-O-galloylsilybin. Chem. Biol. Interact. 2013;205:173–180. doi: 10.1016/j.cbi.2013.07.006. PubMed DOI

Valentova K., Vidlar A., Zatloukalova M., Stuchlik M., Vacek J., Simanek V., Ulrichova J. Biosafety and antioxidant effects of a beverage containing silymarin and arginine. A pilot, human intervention cross-over trial. Food Chem. Toxicol. 2013;56:178–183. doi: 10.1016/j.fct.2013.02.023. PubMed DOI

Wang F., Huang K.X., Yang L.X., Gong J.X., Tao Q.F., Li H.B., Zhao Y., Zeng S., Wu X.M., Stockigt J., et al. Preparation of C-23 esterified silybin derivatives and evaluation of their lipid peroxidation inhibitory and DNA protective properties. Bioorg. Med. Chem. 2009;17:6380–6389. doi: 10.1016/j.bmc.2009.07.023. PubMed DOI

Abourashed E.A., Mikell J.R., Khan I.A. Bioconversion of silybin to phase I and II microbial metabolites with retained antioxidant activity. Bioorg. Med. Chem. 2012;20:2784–2788. doi: 10.1016/j.bmc.2012.03.046. PubMed DOI

Zhu L.F., Xu M., Zhu H.T., Wang D., Yang S.X., Yang C.R., Zhang Y.J. New flavan-3-ol dimer from green tea produced from camellia taliensis in the Ai-Lao Mountains of Southwest China. J. Agric. Food Chem. 2012;60:12170–12176. doi: 10.1021/jf302726t. PubMed DOI

Lu Y.R., Foo L.Y. Antioxidant and radical scavenging activities of polyphenols from apple pomace. Food Chem. 2000;68:81–85. doi: 10.1016/S0308-8146(99)00167-3. DOI

Fujisawa S., Atsumi T., Ishihara M., Kadoma Y. Cytotoxicity, ROS-generation activity and radical-scavenging activity of curcumin and related compounds. Anticancer Res. 2004;24:563–569. PubMed

Osman A.M. Multiple pathways of the reaction of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH center dot) with (+)-catechin: Evidence for the formation of a covalent adduct between DPPH center dot and the oxidized form of the polyphenol. Biochem. Bioph. Res. Commun. 2011;412:473–478. doi: 10.1016/j.bbrc.2011.07.123. PubMed DOI

Kawabata J., Okamoto Y., Kodama A., Makimoto T., Kasai T. Oxidative dimers produced from protocatechuic and gallic esters in the DPPH radical scavenging reaction. J. Agric. Food Chem. 2002;50:5468–5471. PubMed

Yamaguchi H., Ishii E., Tashiro K., Miyazaki S. Role of umbilical vein endothelial cells in hematopoiesis. Leukemia Lymphoma. 1998;31:61–69. doi: 10.3109/10428199809057585. PubMed DOI

Rasmussen C., Thomas-Virnig C., Allen-Hoffmann B.L. Classical human epidermal keratinocyte cell culture. In: Randell S.H., Fulcher M.L., editors. Methods in Molecular Biology. Volume 945. Humana Press; Clifton, NJ, USA: 2013. pp. 161–175. PubMed

Mersch-Sundermann V., Knasmuller S., Wu X.-J., Darroudi F., Kassie F. Use of a human-derivedliver cell line for the detection of cytoprotective, antigenotoxic and cogenotoxic agents. Toxicology. 2004;198:329–340. doi: 10.1016/j.tox.2004.02.009. PubMed DOI

Pham A., Bortolazzo A., White J.B. Rapid dimerization of quercetin through an oxidative mechanism in the presence of serum albumin decreases its ability to induce cytotoxicity in MDA-MB-231 cells. Biochem. Bioph. Res. Commun. 2012;427:415–420. doi: 10.1016/j.bbrc.2012.09.080. PubMed DOI

Figueiredo P., Elhabiri M., Toki K., Saito N., Dangles O., Brouillard R. New aspects of anthocyanin complexation. Intramolecular copigmentation as a means for colour loss? Phytochemistry. 1996;41:301–308. doi: 10.1016/0031-9422(95)00530-7. PubMed DOI

Di Meo F., Garcia J.C.S., Dangles O., Trouillas P. Highlights on anthocyanin pigmentation and copigmentation: A matter of flavonoid π-stacking complexation to be described by dft-d. J. Chem. Theory Comput. 2012;8:2034–2043. doi: 10.1021/ct300276p. PubMed DOI

Nave F., Bras N.F., Cruz L., Teixeira N., Mateus N., Ramos M.J., di Meo F., Trouillas P., Dangles O., de Freitas V. Influence of a flavan-3-ol substituent on the affinity of anthocyanins (pigments) toward vinylcatechin dimers and proanthocyanidins (copigments) J. Phys. Chem. B. 2012;116:14089–14099. doi: 10.1021/jp307782y. PubMed DOI

Velu S.S., di Meo F., Trouillas P., Sancho-Garcia J.C., Weber J.F. Regio- and stereocontrolled synthesis of oligostilbenoids: Theoretical highlights at the supramolecular level. J. Nat. Prod. 2013;76:538–546. doi: 10.1021/np300705p. PubMed DOI

Gazak R., Marhol P., Purchartova K., Monti D., Biedermann D., Riva S., Cvak L., Kren V. Large-scale separation of silybin diastereoisomers using lipases. Process Biochem. 2010;45:1657–1663. doi: 10.1016/j.procbio.2010.06.019. DOI

Zatloukalova M., Orolinova E., Kubala M., Hrbac J., Vacek J. Electrochemical determination of transmembrane protein Na+/K+-ATPase and its cytoplasmic loop C45. Electroanalysis. 2012;24:1758–1765.

Joyeux M., Mortier F., Fleurentin J. Screening of antiradical, antilipoperoxidant and hepatoprotective effects of 9 plant-extracts used in caribbean folk medicine. Phytother. Res. 1995;9:228–230. doi: 10.1002/ptr.2650090316. DOI

Siekevitz P., Sidney P.C., Nathan O.K. Methodsin Enzymology. Volume 5. Academic Press; Waltham, MA, USA: 1962. Preparation of microsomes and submicrosomal fractions: Mammalian; pp. 61–68.

Bradford M.M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal. Biochem. 1976;72:248–254. doi: 10.1016/0003-2697(76)90527-3. PubMed DOI

Council for International Organizations of Medical Sciences International ethical guidelines for biomedical research involving human subjects. Bull. Med. Ethics. 2002;182:17–23. PubMed

Gazak R., Valentova K., Fuksova K., Marhol P., Kuzma M., Medina M.A., Oborna I., Ulrichova J., Kren V. Synthesis and antiangiogenic activity of new silybin galloyl esters. J. Med. Chem. 2011;54:7397–7407. doi: 10.1021/jm201034h. PubMed DOI

Atanasova G., Jans R., Zhelev N., Mitev V., Poumay Y. Effects of the cyclin-dependent kinase inhibitor CYC202 (R-roscovitine) on the physiology of cultured human keratinocytes. Biochem. Pharmacol. 2005;70:824–836. doi: 10.1016/j.bcp.2005.06.005. PubMed DOI

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