Antioxidant, DNA cleavage and cellular effects of silibinin and a new oxovanadium(IV)/silibinin complex.

L. NASO; E. G. FERRER; NATALIYA BUTENKO; ISABEL CAVACO; LUIS LEZAMA; ROJO, T.; S. B. ETCHEVERRY; P. A. M. W ILLIAMS

JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY

SPRINGER

Lugar: Berlin; Año: 2011 vol. 16 p. 653 - 668

0949-8257

A new complex of the oxovanadium(IV) cationwith the flavolignan silibinin has been synthesized andcharacterized. Vanadium compounds show interesting biologicaland pharmacological properties and some of themdisplay antitumoral actions. Flavonoids are part of a largergroup of antioxidant compounds called polyphenols whichmay inhibit the proliferation and growth of cancer cells. Theantioxidant and antitumoral effects of silibinin and its oxovanadium(IV) complex were investigated. Silibinin acted asa very strong antioxidant and its complexation with oxovanadium(IV) improved this behavior. Besides, the generationof reactive oxygen species (ROS) by this compound wasfavored in tumoral (UMR106) cells and correlated with thedeleterious behavior in the proliferation of this cell line.Conversely, silibinin did not exert any effect on the proliferationof normal osteoblasts (MC3T3E1). The cytotoxicaction andROSgeneration of the oxovanadium(IV) complexwas more effective in tumoral cells. This behavior was notconsistent with cleavingDNA of plasmid DNA pA1 becauseno significant cleaving activity was observed in both cases.These results suggest that the main deleterious mechanismsmay take place through cytotoxic effects more than genotoxicactions. A comparison with our own findings on thebehavior of other flavonoids and their vanadyl(IV) complexhas also been performed.