title: Low cytotoxicity of inorganic nanotubes and fullerene-like nanostructures in human bronchial epithelial cells: relation to inflammatory gene induction and antioxidant response.
abstract: The cytotoxicity of tungsten disulfide nano tubes (INT-WS2) and inorganic fullerene-like molybdenum disulfide (IF-MoS2) nanoparticles (NPs) used in industrial and medical applications was evaluated in comparison to standard environmental particulate matter. The IF-MoS2 and INT-WS2 reside in vesicles/inclusion bodies, suggestive of endocytic vesicles. In cells representing the respiratory, immune and metabolic systems, both IF-MoS2 and INT-WS2 NPs remained nontoxic compared to equivalent concentrations (up to 100 μg/mL in the medium) of silica dioxide (SiO2), diesel engine-derived and carbon black NPs, which induced cell death. Associating with this biocompatibility of IF-MoS2\INT-WS2, we demonstrate in nontransformed human bronchial cells (NL-20) relative low induction of the pro-inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α. Moreover, IF-MoS2 and INT-WS2 activated antioxidant response as measured by the antioxidant response element (ARE) using a luciferase reporter, and induced Nrf2-mediated Phase II detoxification genes. Collectively, our findings suggest that the lower cytotoxicity of IF-MoS2 and INT-WS2 NPs does not reflect general biological inertness. Rather, compared to other NP's, it likely results from decreased pro-inflammatory activation, but a comparable significant capacity to induce protective antioxidant/detoxification defense mechanisms.
authors.affiliation: Department of Earth and Planetary Sciences, Weizmann Institute of Science , Rehovot 76100, Israel.
authors.forename: Michal
authors.initials: M
authors.lastname: Pardo
authors.forename: Timor
authors.initials: T
authors.lastname: Shuster-Meiseles
authors.forename: Smadar
authors.initials: S
authors.lastname: Levin-Zaidman
authors.forename: Assaf
authors.initials: A
authors.lastname: Rudich
authors.forename: Yinon
authors.initials: Y
authors.lastname: Rudich
mesh_terms: D000975:Antioxidants / Q000032:analysis / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D004220:Disulfides / Q000633:toxicity; D004847:Epithelial Cells / Q000187:drug effects*; D037741:Fullerenes / Q000633:toxicity*; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D008982:Molybdenum / Q000633:toxicity; D043942:Nanotubes / Q000633:toxicity*; D052638:Particulate Matter / Q000378:metabolism; D012822:Silicon Dioxide / Q000633:toxicity; D053260:Soot / Q000633:toxicity; D014414:Tungsten / Q000633:toxicity
chemical_list: D000975:Antioxidants; D016207:Cytokines; D004220:Disulfides; D037741:Fullerenes; D052638:Particulate Matter; D053260:Soot; D012822:Silicon Dioxide; D008982:Molybdenum; D014414:Tungsten; C082964:molybdenum disulfide