title: Photoactivated cytotoxicity of ferrocenyl-terpyridine oxovanadium(IV) complexes of curcuminoids.
abstract: Oxovanadium(IV) complexes, viz. [VO(Fc-tpy)(Curc)](ClO4) (1), [VO(Fc-tpy)(bDHC)](ClO4) (2), [VO(Fc-tpy)(bDMC)](ClO4) (3) and [VO(Ph-tpy)(Curc)](ClO4) (4), of 4'-ferrocenyl-2,2':6',2″-terpyridine (Fc-tpy) and 4'-phenyl-2,2':6',2″-terpyridine (Ph-tpy) and monoanionic curcumin (Curc), bis-dehydroxycurcmin (bDHC) and bis-demethoxycurcumin (bDMC) were prepared, characterized and their photo-induced DNA cleavage activity and photocytotoxicity in visible light studied. The ferrocenyl complexes 1-3 showed an intense metal-to-ligand charge transfer band near 585 nm in DMF and displayed Fc(+)/Fc and V(IV)/V(III) redox couples near 0.65 V and -1.05 V vs. SCE in DMF-0.1 M TBAP. The complexes as avid binders to calf thymus DNA showed significant photocleavage of plasmid DNA in red light of 647 nm forming OH radicals. The complexes showed photocytotoxicity in HeLa and Hep G2 cancer cells in visible light of 400-700 nm with low dark toxicity. ICP-MS and fluorescence microscopic studies exhibited significant cellular uptake of the complexes within 4 h of treatment with complexes. The treatment with complex 1 resulted in the formation of reactive oxygen species inside the HeLa cells which was evidenced from the DCFDA assay.
authors.affiliation: Department of Inorganic and Physical Chemistry, Indian Institute of Science, Sir C.V. Raman Avenue, Bangalore 560012, India.
authors.forename: Babu
authors.initials: B
authors.lastname: Balaji
authors.affiliation: Department of Biochemistry, Indian Institute of Science, Sir C.V. Raman Avenue, Bangalore 560 012, India.
authors.forename: Babita
authors.initials: B
authors.lastname: Balakrishnan
authors.affiliation: Department of Inorganic and Physical Chemistry, Indian Institute of Science, Sir C.V. Raman Avenue, Bangalore 560012, India.
authors.forename: Sravanakumar
authors.initials: S
authors.lastname: Perumalla
authors.affiliation: Department of Biochemistry, Indian Institute of Science, Sir C.V. Raman Avenue, Bangalore 560 012, India. Electronic address: anjali@biochem.iisc.ernet.in.
authors.forename: Anjali A
authors.initials: AA
authors.lastname: Karande
authors.affiliation: Department of Inorganic and Physical Chemistry, Indian Institute of Science, Sir C.V. Raman Avenue, Bangalore 560012, India. Electronic address: akhil_chakravarty@yahoo.co.in.
authors.forename: Akhil R
authors.initials: AR
authors.lastname: Chakravarty
mesh_terms: D000818:Animals; D001692:Biological Transport; D002417:Cattle; D045744:Cell Line, Tumor; D003474:Curcumin / Q000737:chemistry*; D004247:DNA / Q000378:metabolism; D053837:DNA Cleavage / Q000187:drug effects / Q000528:radiation effects; D004355:Drug Stability; D005296:Ferrous Compounds / Q000737:chemistry*; D006801:Humans; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D000075163:Metallocenes; D009942:Organometallic Compounds / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D017319:Photosensitizing Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D011725:Pyridines / Q000737:chemistry*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014639:Vanadium / Q000737:chemistry*
chemical_list: D005296:Ferrous Compounds; D000075163:Metallocenes; D009942:Organometallic Compounds; D017319:Photosensitizing Agents; D011725:Pyridines; D017382:Reactive Oxygen Species; D014639:Vanadium; D004247:DNA; C427203:calf thymus DNA; D003474:Curcumin; C023666:pyridine; C004998:ferrocene
keywords: Cellular imaging; Curcuminoids; Ferrocene; Medicinal chemistry; Photocytotoxicity; Vanadium