title: Cytotoxicity of a vanadyl(IV) complex with a multidentate oxygen donor in osteoblast cell lines in culture.
abstract: Strong chelating ligands as oxodiacetate (oda) are model systems to study the process of metal trapping by living organisms. Vanadium compounds display interesting biological and pharmacological actions. In vertebrates, vanadium is stored mainly in bones. In the present study we report the effects of the complex of oda with vanadyl(IV) cation, VO(oda), on two osteoblast cell lines, one normal (MC3T3E1) and the other tumoral (UMR106). VO(oda) exerted cytotoxic actions in osteoblasts as it was determined through a dose-dependent decrease in cell proliferation, and morphological and actin alterations. The putative mechanisms underlying VO(oda) deleterious effects were also investigated. The complex increased the level of ROS which correlated with a decreased in GSH/GSSG ratio. Besides, VO(oda) induced a dissipation of the mitochondria membrane potential (MMP) and promoted an increase in ERK cascade phosphorylation, which is involved in the regulation of cellular death and survival. All the effects were more pronounced in MC3T3-E1 than in UMR106 cells. ERK activation was inhibited by PD98059, Wortmanin and the ROS scavenger NAC (N-acetyl cysteine). These results suggest that VO(oda) stimulated ERKs phosphorilation by induction of free radicals involving kinases upstream of ERK pathway. The inhibitory effect of the complex on cell proliferation was partially reversed in both cell lines by NAC. Moreover, PD98059 and Wortmanin also partially reversed the inhibition of cell proliferation in the tumoral osteoblasts. The use of specific inhibitors and ROS scavengers suggested the involvement of oxidative stress, MMP alterations and ERK pathway in the apoptotic actions of this complex.
authors.affiliation: Bioquímica Patológica, Facultad de Ciencias Exactas, UNLP, 47 y 115 (1900) La Plata, Argentina.
authors.forename: J
authors.initials: J
authors.lastname: Rivadeneira
authors.forename: A L
authors.initials: AL
authors.lastname: Di Virgilio
authors.forename: D A
authors.initials: DA
authors.lastname: Barrio
authors.forename: C I
authors.initials: CI
authors.lastname: Muglia
authors.forename: L
authors.initials: L
authors.lastname: Bruzzone
authors.forename: S B
authors.initials: SB
authors.lastname: Etcheverry
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D003603:Cytotoxins / Q000737:chemistry* / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D019803:Glutathione Disulfide / Q000378:metabolism; D042541:Intracellular Space / Q000187:drug effects; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009499:Neutral Red; D009942:Organometallic Compounds / Q000737:chemistry* / Q000494:pharmacology*; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry*; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D014639:Vanadium / Q000737:chemistry*
chemical_list: D000199:Actins; D003603:Cytotoxins; D009942:Organometallic Compounds; D017382:Reactive Oxygen Species; D014639:Vanadium; D009499:Neutral Red; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D005978:Glutathione; D010100:Oxygen; D019803:Glutathione Disulfide