title: Antioxidant, DNA cleavage, and cellular effects of silibinin and a new oxovanadium(IV)/silibinin complex.
abstract: A new complex of the oxovanadium(IV) cation with the flavolignan silibinin has been synthesized and characterized. Vanadium compounds show interesting biological and pharmacological properties and some of them display antitumoral actions. Flavonoids are part of a larger group of antioxidant compounds called polyphenols which may inhibit the proliferation and growth of cancer cells. The antioxidant and antitumoral effects of silibinin and its oxovanadium(IV) complex were investigated. Silibinin acted as a very strong antioxidant and its complexation with oxovanadium(IV) improved this behavior. Besides, the generation of reactive oxygen species (ROS) by this compound was favored in tumoral (UMR106) cells and correlated with the deleterious behavior in the proliferation of this cell line. Conversely, silibinin did not exert any effect on the proliferation of normal osteoblasts (MC3T3E1). The cytotoxic action and ROS generation of the oxovanadium(IV) complex was more effective in tumoral cells. This behavior was not consistent with cleaving DNA of plasmid DNA pA1 because no significant cleaving activity was observed in both cases. These results suggest that the main deleterious mechanisms may take place through cytotoxic effects more than genotoxic actions. A comparison with our own findings on the behavior of other flavonoids and their vanadyl(IV) complex has also been performed.
authors.affiliation: Centro de Química Inorgánica (CEQUINOR/CONICET, UNLP), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina.
authors.forename: Luciana G
authors.initials: LG
authors.lastname: Naso
authors.forename: Evelina G
authors.initials: EG
authors.lastname: Ferrer
authors.forename: Nataliya
authors.initials: N
authors.lastname: Butenko
authors.forename: Isabel
authors.initials: I
authors.lastname: Cavaco
authors.forename: Luis
authors.initials: L
authors.lastname: Lezama
authors.forename: Teófilo
authors.initials: T
authors.lastname: Rojo
authors.forename: Susana B
authors.initials: SB
authors.lastname: Etcheverry
authors.forename: Patricia A M
authors.initials: PA
authors.lastname: Williams
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000975:Antioxidants / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D053837:DNA Cleavage / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D004578:Electron Spin Resonance Spectroscopy; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D010957:Plasmids / Q000187:drug effects; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D000077385:Silybin; D012838:Silymarin / Q000737:chemistry / Q000494:pharmacology*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013329:Structure-Activity Relationship; D014638:Vanadates / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D000975:Antioxidants; D009942:Organometallic Compounds; D017382:Reactive Oxygen Species; D012838:Silymarin; C075743:oxovanadium IV; D014638:Vanadates; D000077385:Silybin