title: Fullerene-polyvinylpyrrolidone clathrate localizes in the cytoplasm to prevent Ultraviolet-A ray-induced DNA-fragmentation and activation of the transcriptional factor NF-kappaB.
abstract: By Western blot and immunostaining we proved that polyvinylpyrrolidone (PVP)-wrapped fullerene molecules (PVP-fullerene) could combine the 8- and 53-kb proteins which localize in the membrane of human skin keratinocytes HaCaT. Only fullerene molecules are able to cross the lipid membrane and conjugate 53-kb proteins in the cytosol. There are no fullerene molecules detectable in the nucleus or cytoskeleton. Ultraviolet-A (UVA)-irradiation on HaCaT or normal human epidermal melanocytes (NHEM) caused nuclear fragmentations, lowering of intracellular DNA-contents below diploidy, concurrently with the repressed DNA synthesis and the increased DNA-3'OH cleavage terminals, all of which were repressed by PVP-fullerene, as shown by flow cytometry and PI- or TUNEL-stain fluorography. Translocation of the transcriptional factor NF-kappaB in the cytoplasm to the nucleus of the keratinocytes was caused with UVA and repressed by PVP-fullerene with cytoprotective effects. Thus, the PVP-fullerene may be developed as a UV-protective agent with DNA-preservative effects owing to its combinative ability to molecules in the cytoplasm and cytomembrane, and then represses cellular oxidative stress and blocks abnormal signal pathways.
authors.affiliation: Laboratory of Cell-Death Control BioTechnology, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Nanatsuka 562, Shobara, Hiroshima 727-0023, Japan.
authors.forename: Li
authors.initials: L
authors.lastname: Xiao
authors.forename: Hisae
authors.initials: H
authors.lastname: Aoshima
authors.forename: Yasukazu
authors.initials: Y
authors.lastname: Saitoh
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Miwa
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D003593:Cytoplasm / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D053938:DNA Fragmentation / Q000187:drug effects / Q000528:radiation effects*; D037741:Fullerenes / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D008544:Melanocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D016328:NF-kappa B / Q000378:metabolism*; D010539:Permeability / Q000187:drug effects / Q000528:radiation effects; D011205:Povidone / Q000378:metabolism / Q000494:pharmacology*; D020011:Protective Agents / Q000494:pharmacology; D021381:Protein Transport / Q000187:drug effects / Q000528:radiation effects; D051996:Transcription Factor RelA; D014466:Ultraviolet Rays
chemical_list: D037741:Fullerenes; D016328:NF-kappa B; D020011:Protective Agents; D051996:Transcription Factor RelA; D011205:Povidone