title: N-acetylcysteine Attenuates Cobalt Nanoparticle-Induced Cytotoxic Effects through Inhibition of Cell Death, Reactive Oxygen Species-related Signaling and Cytokines Expression.
abstract: OBJECTIVE
  Complex cobalt-chromium alloys, bearing surfaces of the second-generation metal-on-metal (MoM) hip prostheses, are subject to wear and generate cobalt nanoparticles (CoNPs). CoNPs could reduce cellular viability, activate the mitogen-activated protein kinase (MAPK) pathway and increase cell apoptosis via reactive oxygen species (ROS). However, the detailed mechanisms of ROS functioning on CoNP-mediated signaling molecules and cytotoxicity has not yet been fully demonstrated. The present study investigated the functional role of N-acetylcysteine (NAC) in reversing the activation of ROS signaling pathways triggered by CoNPs in normal mice kidney cells (TCMK-1 cells).
  
  
  METHODS
  After being pretreated with NAC, TCMK-1 cells were treated with 300-700 μmol/L CoNPs, then, CCK-8 assay was used to verify the survival of TCMK-1 cells. Annexin V/PI staining was performed to investigate the apoptosis of TCMK-1 cells after NAC and different concentrations of CoNP treatments. In addition, western blot was performed to identify the cytokine (p-ERK, p-p38, and p-JNK) expression of the ROS-related MAPK signaling pathway.
  
  
  RESULTS
  Apoptosis rate of TCMK-1 cells was increased obviously after different concentrations of CoNP treatment. However, TCMK-1 cells, pretreated with NAC, exhibited a significantly decreased apoptosis rate. In addition, p-ERK, p-p38, and p-JNK expressions were increased with CoNP treatment, which indicated that CoNPs could activate the MAPK pathway. Interestingly, this entire stimulated phenomenon by CoNPs was reversed with NAC treatment.
  
  
  CONCLUSIONS
  These findings indicated that NAC could reverse CoNP-induced cytotoxicity by inhibiting ROS-induced cell death and cytokine expression. To our knowledge, this is the first report that describes how CoNP-induced cytotoxicity in TCMK-1 cells could be attenuated by anti-oxidative agents (NAC), which may function through inhibition of cell death and ROS.
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Ya-Ke
authors.initials: YK
authors.lastname: Liu
authors.affiliation: Department of Orthopaedics, Nantong Third People's Hospital of Nantong University, Nantong, China.
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Yang
authors.affiliation: Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, China.
authors.forename: Meng-Hong
authors.initials: MH
authors.lastname: Wang
authors.affiliation: Department of Orthopaedics, Nantong Third People's Hospital of Nantong University, Nantong, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Orthopaedics, Nantong Third People's Hospital of Nantong University, Nantong, China.
authors.forename: Fan
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Hui-Lin
authors.initials: HL
authors.lastname: Yang
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D002460:Cell Line; D003035:Cobalt / Q000633:toxicity*; D016207:Cytokines / Q000378:metabolism*; D016166:Free Radical Scavengers / Q000494:pharmacology*; D006622:Hip Prosthesis / Q000009:adverse effects; D061825:Metal-on-Metal Joint Prostheses / Q000009:adverse effects; D051379:Mice; D053758:Nanoparticles / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D015415:Biomarkers; D016207:Cytokines; D016166:Free Radical Scavengers; D017382:Reactive Oxygen Species; D003035:Cobalt; D000111:Acetylcysteine
keywords: 
  N-acetylcysteine; Cobalt nanoparticle TCMK-1 cells; Cytotoxicity; Metal-on-metal hip prostheses