Gold nanoparticles do not induce myotube cytotoxicity but increase the susceptibility to cell death

Toxicol In Vitro. 2015 Aug;29(5):819-27. doi: 10.1016/j.tiv.2015.02.010. Epub 2015 Mar 16.

Abstract

Gold nanoparticles (AuNP) have been widely used for many applications, including as biological carriers. A better understanding concerning AuNP safety on muscle cells is crucial, since it could be a potential tool in the nanomedicine field. Here, we describe the impact of polyethylene glycol-coated gold nanoparticles (PEG-AuNP) interaction with differentiated skeletal muscle C2C12 cells on cell viability, mitochondria function, cell signaling related to survival, cytokine levels and susceptibility to apoptosis. Intracellular localization of 4.5 nm PEG-AuNP diameter size was evidenced by STEM-in-SEM in myotube cells. Methods for cytotoxicity analysis showed that PEG-AuNP did not affect cell viability, but intracellular ATP levels and mitochondrial membrane potential increased. Phosphorylation of ERK was not altered but p-AKT levels reduced (p<0.01). Pre-treatment of cells with PEG-AuNP followed by staurosporine induction increased the caspases-3/7 activity. Indeed, cytokines analysis revealed a sharp increase of IFN-γ and TGF-β1 levels after PEG-AuNP treatment, suggesting that inflammatory and fibrotic phenotypes process were activated. These data demonstrate that PEG-AuNP affect the myotube physiology leading these cells to be more susceptible to death stimuli in the presence of staurosporine. Altogether, these results present evidence that PEG-AuNP affect the susceptibility to apoptosis of muscle cells, contributing to development of safer strategies for intramuscular delivery.

Keywords: Bioengineering; Gold nanoparticle; Inflammation; Nanotoxicity; PEG; Skeletal muscle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Animals
  • Caspase 3 / metabolism
  • Caspase 7 / metabolism
  • Cell Death / drug effects
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Gold / chemistry
  • Gold / toxicity*
  • Interferon-gamma / metabolism
  • Membrane Potential, Mitochondrial / drug effects
  • Metal Nanoparticles / chemistry
  • Metal Nanoparticles / toxicity*
  • Mice
  • Muscle Fibers, Skeletal / drug effects*
  • Muscle Fibers, Skeletal / metabolism
  • Polyethylene Glycols / chemistry
  • Proto-Oncogene Proteins c-akt / metabolism
  • Transforming Growth Factor beta / metabolism

Substances

  • Transforming Growth Factor beta
  • Polyethylene Glycols
  • Gold
  • Interferon-gamma
  • Adenosine Triphosphate
  • Proto-Oncogene Proteins c-akt
  • Casp7 protein, mouse
  • Caspase 3
  • Caspase 7