title: Multi-walled carbon nanotubes (MWCNTs) lead to growth retardation, antioxidant depletion, and activation of the ERK signaling pathway but decrease copper bioavailability in the monogonont rotifer (Brachionus koreanus).
abstract: To examine the toxic effects of multi-walled carbon nanotubes (MWCNTs) in the marine environment, we first exposed the monogonont rotifer (Brachionus koreanus) to MWCNTs in the presence of copper. The acute toxicity of copper decreased significantly with a decrease in copper bioavailability resulting from MWCNT exposure. Furthermore, we examined the effects of MWCNT exposure on reproductive capacity, population growth rate, growth patterns, antioxidant systems, and mitogen-activated protein kinase (MAPK) activation. Reproductive capacity, population growth rate, and body growth rate were significantly suppressed in B. koreanus in response to 1.3-4mg/L MWCNT exposure. Furthermore, MWCNTs induced the generation of reactive oxygen species (ROS) and decreased the antioxidant enzymatic activities of catalase (CAT) and glutathione reductase (GR). However, the enzymatic activity of glutathione S-transferase (GST) was up-regulated after a 24 h-exposure to 100mg/L MWCNTs. Exposure to 100mg/L MCWNTs induced extracellular signal-regulated kinase (ERK) activation in B. koreanus, suggesting that p-ERK may mediate the adverse effects of MWCNTs in B. koreanus via the MAPK signaling pathway. Our results provide insight into the mechanistic basis of the ecotoxicological effects of MWCNTs in the marine environment.
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Jin Wuk
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Hye-Min
authors.initials: HM
authors.lastname: Kang
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Eun-Ji
authors.initials: EJ
authors.lastname: Won
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Dae-Sik
authors.initials: DS
authors.lastname: Hwang
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Duck-Hyun
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 04763, South Korea.
authors.forename: Su-Jae
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea. Electronic address: jslee2@skku.edu.
authors.forename: Jae-Seong
authors.initials: JS
authors.lastname: Lee
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001682:Biological Availability; D003300:Copper / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D037742:Nanotubes, Carbon / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012403:Rotifera / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D000975:Antioxidants; D037742:Nanotubes, Carbon; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; D003300:Copper; D005980:Glutathione Reductase; D005982:Glutathione Transferase
keywords: Brachionus koreanus; Life cycle index; Mitogen-activated protein kinase; Multi-walled carbon nanotubes; Oxidative stress