Zinc Oxide Particles Induce Activation of the Lysosome–Autophagy System

Metal-oxide-based materials are highly versatile and used in a wide variety of applications ranging from medical technology to personal care products. Generally recognized as safe by the US Food and Drug Administration, zinc oxide (ZnO) has been increasingly used in pharmaceutical, cosmetic, food, and commodity chemical industries. As a result, exposure to nano- and micron-sized ZnO particles through occupational processes and consumer products is increasing and has raised concerns over the health effects associated with the large-scale production and commercialization of ZnO-based materials. It is therefore important to investigate the interaction of ZnO particles with biological systems and elucidate the consequent effect on cell physiology. Of particular interest is the autophagic response to zinc oxide particles, as autophagy is the first line of defense activated in response to the uptake of foreign materials. As the main cellular catabolic pathway, the lysosome–autophagy system plays an important ho...