Nanomaterial-induced cell death in pulmonary and hepatic cells following exposure to three different metallic materials: The role of autophagy and apoptosis

TY - JOUR

T1 - Nanomaterial-induced cell death in pulmonary and hepatic cells following exposure to three different metallic materials

T2 - The role of autophagy and apoptosis

AU - Kermanizadeh, Ali

AU - Jantzen, Kim

AU - Ward, Michael B

AU - Durhuus, Jon Ambæk

AU - Juel Rasmussen, Lene

AU - Loft, Steffen

AU - Møller, Peter

PY - 2017/2/7

Y1 - 2017/2/7

N2 - Autophagy is the catabolic process involving the sequestration of the cytoplasm within double-membrane vesicles, which fuse with lysosomes to form autolysosomes in which autophagic targets are degraded. Since most endocytic routes of nanomaterial uptake converge upon the lysosome and the possibility that autophagy induction by NMs may be an attempt by the cell to self-preserve following the external challenge, this study investigated the role of autophagy following exposure to a panel of widely used metal-based NMs with high toxicity (Ag and ZnO) or low toxicity (TiO2) in a pulmonary (A549) and hepatic (HepG2) cell line. The in vitro exposure to the Ag and ZnO NMs resulted in the induction of both apoptosis and autophagy pathways in both cell types. However, the progression of autophagy was blocked in the formation of the autolysosome, which coincided with morphologic changes in the actin cytoskeleton. This response was not observed following the exposure to low-toxicity TiO2 NMs. Overall, the results show that high toxicity NMs can cause a dysfunction in the autophagy pathway which is associated with apoptotic cell death.

AB - Autophagy is the catabolic process involving the sequestration of the cytoplasm within double-membrane vesicles, which fuse with lysosomes to form autolysosomes in which autophagic targets are degraded. Since most endocytic routes of nanomaterial uptake converge upon the lysosome and the possibility that autophagy induction by NMs may be an attempt by the cell to self-preserve following the external challenge, this study investigated the role of autophagy following exposure to a panel of widely used metal-based NMs with high toxicity (Ag and ZnO) or low toxicity (TiO2) in a pulmonary (A549) and hepatic (HepG2) cell line. The in vitro exposure to the Ag and ZnO NMs resulted in the induction of both apoptosis and autophagy pathways in both cell types. However, the progression of autophagy was blocked in the formation of the autolysosome, which coincided with morphologic changes in the actin cytoskeleton. This response was not observed following the exposure to low-toxicity TiO2 NMs. Overall, the results show that high toxicity NMs can cause a dysfunction in the autophagy pathway which is associated with apoptotic cell death.

U2 - 10.1080/17435390.2017.1279359

DO - 10.1080/17435390.2017.1279359

M3 - Journal article

C2 - 28055265

SN - 1743-5390

VL - 11

SP - 184

EP - 200

JO - Nanotoxicology

JF - Nanotoxicology

IS - 2

ER -