The mechanism of cell-damaging reactive oxygen generation by colloidal fullerenes.

Because of the ability to induce cell death in certain conditions, the fullerenes (C(60)) are potential anticancer and toxic agents. The colloidal suspension of crystalline C(60) (nano-C(60), nC(60)) is extremely toxic, but the mechanisms of its cytotoxicity are not completely understood. By combining experimental analysis and mathematical modelling, we investigate the requirements for the reactive oxygen species (ROS)-mediated cytotoxicity of different nC(60) suspensions, prepared by solvent exchange method in tetrahydrofuran (THF/nC(60)) and ethanol (EtOH/nC(60)), or by extended mixing in water (aqu/nC(60)). With regard to their capacity to generate ROS and cause mitochondrial depolarization followed by necrotic cell death, the nC(60) suspensions are ranked in the following order: THF/nC(60)>EtOH/nC(60)>aqu/nC(60). Mathematical modelling of singlet oxygen ((1)O(2)) generation indicates that the (1)O(2)-quenching power (THF/nC(60)<EtOH/nC(60)<aqu/nC(60)) of the solvent intercalated in the fullerene crystals determines their ability to produce ROS and cause cell damage. These data could have important implications for toxicology and biomedical application of colloidal fullerenes.

[1]  L. Klotz,et al.  Toxic and signaling effects of photochemically or chemically generated singlet oxygen in biological systems. , 1997, Biological chemistry.

[2]  Y. Lion,et al.  New method of detecting singlet oxygen production , 1976, Nature.

[3]  Y. Rubin,et al.  TRIPLET-STATE PROPERTIES AND SINGLET OXYGEN GENERATION IN A HOMOLOGOUS SERIES OF FUNCTIONALIZED FULLERENE DERIVATIVES , 1999 .

[4]  Yukihiro Goda,et al.  Active oxygen species generated from photoexcited fullerene (C60) as potential medicines: O2-* versus 1O2. , 2003, Journal of the American Chemical Society.

[5]  C. Franceschi,et al.  C60 carboxyfullerene exerts a protective activity against oxidative stress-induced apoptosis in human peripheral blood mononuclear cells. , 2000, Biochemical and biophysical research communications.

[6]  M. Lekka,et al.  Singlet oxygen (1Δg)-mediated oxidation of cellular and subcellular components: ESR and AFM assays , 2005 .

[7]  H. Shinohara,et al.  Fullerenes in medicinal chemistry and their biological applications. , 2001, Mini reviews in medicinal chemistry.

[8]  Zoran Markovic,et al.  Multiple mechanisms underlying the anticancer action of nanocrystalline fullerene. , 2007, European journal of pharmacology.

[9]  Eva Oberdörster,et al.  Ecotoxicology of carbon-based engineered nanoparticles: Effects of fullerene (C60) on aquatic organisms , 2006 .

[10]  D. Choi,et al.  Buckminsterfullerenol Free Radical Scavengers Reduce Excitotoxic and Apoptotic Death of Cultured Cortical Neurons , 1996, Neurobiology of Disease.

[11]  Alok Dhawan,et al.  Stable colloidal dispersions of C60 fullerenes in water: evidence for genotoxicity. , 2006, Environmental science & technology.

[12]  Robert L. Whetten,et al.  Photophysical properties of C60 , 1991 .

[13]  R. Scurlock,et al.  Effect of solvent on the rate constant for the radiative deactivation of singlet molecular oxygen (1.DELTA.gO2) , 1987 .

[14]  S. L. Issler,et al.  Involvement of the azide radical in the quenching of singlet oxygen by azide anion in water , 1982 .

[15]  M. Prato,et al.  Fullerene derivatives: an attractive tool for biological applications. , 2003, European journal of medicinal chemistry.

[16]  Miroslav D. Dramićanin,et al.  Inactivation of nanocrystalline C60 cytotoxicity by γ-irradiation , 2006 .

[17]  Zoran Markovic,et al.  Distinct cytotoxic mechanisms of pristine versus hydroxylated fullerene. , 2006, Toxicological sciences : an official journal of the Society of Toxicology.

[18]  N. G. Mironova,et al.  A mathematical model of the photodynamic fullerene-oxygen action on biological tissues , 2005 .

[19]  R. Battino,et al.  The Solubility of Oxygen and Ozone in Liquids , 1983 .

[20]  S Fiorito,et al.  Toxicity and biocompatibility of carbon nanoparticles. , 2006, Journal of nanoscience and nanotechnology.

[21]  J. Font,et al.  C60 Fullerene-based materials as singlet oxygen O2(1Δg) photosensitizers: a time-resolved near-IR luminescence and optoacoustic study , 2001 .

[22]  J. West,et al.  Nano-C60 cytotoxicity is due to lipid peroxidation. , 2005, Biomaterials.

[23]  C. Thompson,et al.  Death by design: apoptosis, necrosis and autophagy. , 2004, Current opinion in cell biology.

[24]  T. Luh,et al.  Carboxyfullerene Prevents Iron‐Induced Oxidative Stress in Rat Brain , 1999, Journal of neurochemistry.

[25]  E. Fernandes,et al.  New noncellular fluorescence microplate screening assay for scavenging activity against singlet oxygen , 2007, Analytical and bioanalytical chemistry.

[26]  K. Ausman,et al.  C60 in water: nanocrystal formation and microbial response. , 2005, Environmental science & technology.

[27]  N. Kratowich,et al.  THE QUENCHING OF SINGLET OXYGEN BY AMINO ACIDS AND PROTEINS , 1975, Photochemistry and photobiology.

[28]  Maurizio Prato,et al.  Excited-State Properties of C60 Fullerene Derivatives , 2000 .

[29]  B. Röder,et al.  TEMPORAL and SPECTRAL SEPARATION OF SINGLET OXYGEN LUMINESCENCE FROM NEAR INFRARED EMITTING PHOTOSENSITIZERS , 1993 .

[30]  H. Krug,et al.  Oops they did it again! Carbon nanotubes hoax scientists in viability assays. , 2006, Nano letters.

[31]  Mason B. Tomson,et al.  Naphthalene Adsorption and Desorption from Aqueous C60 Fullerene , 2004 .

[32]  V. Trajković,et al.  Novel platinum(IV) complexes induce rapid tumor cell death in vitro , 2005, International journal of cancer.

[33]  E. Land,et al.  Reactions of e−aq, co2•−, ho, o2•− and o2(1δg) with a dendro[60]fullerene and c60[c(cooh)2]n (n = 2–6) 1 , 2000 .

[34]  E. Oberdörster.  Manufactured Nanomaterials (Fullerenes, C60) Induce Oxidative Stress in the Brain of Juvenile Largemouth Bass , 2004, Environmental health perspectives.

[35]  D. Brenner,et al.  The mitochondrial permeability transition in cell death: a common mechanism in necrosis, apoptosis and autophagy. , 1998, Biochimica et biophysica acta.

[36]  J. West,et al.  The Differential Cytotoxicity of Water-Soluble Fullerenes , 2004 .

[37]  Kinetics of fullerene triplet states , 1997 .

[38]  R K Jain,et al.  Openings between defective endothelial cells explain tumor vessel leakiness. , 2000, The American journal of pathology.

[39]  D. Snelling,et al.  Production of singlet oxygen in the benzene oxygen photochemical system , 1968 .

[40]  Stephen R. Wilson,et al.  [60]fullerene is a powerful antioxidant in vivo with no acute or subacute toxicity. , 2005, Nano letters.

[41]  Shen,et al.  Carboxyfullerenes as neuroprotective agents. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[42]  G. Andrievsky,et al.  Is the C60 Fullerene Molecule Toxic?! , 2005 .

[43]  G. Oberdörster,et al.  Nanotoxicology: An Emerging Discipline Evolving from Studies of Ultrafine Particles , 2005, Environmental health perspectives.

[44]  Eva Oberdörster,et al.  Toxicity of an engineered nanoparticle (fullerene, C60) in two aquatic species, Daphnia and fathead minnow. , 2006, Marine environmental research.