Leila Sadeghi - Department of Animal Biology, Faculty of Natural Science, University of Tabriz, Tabriz, Iran

Iron oxide nanoparticles (Fe2O3-NPs) are being used in an increasing number of fields such as molecular imaging in the context of Magnetic Resonance Imaging, ultrasound, optical imaging, and X-ray imaging. This widespread application of different sized of Fe2O3-NP in the biomedical field raises concerns over their increased exposing to tissues and organs of the human and animals. This study investigated the molecular and cytotoxic effects of Fe2O3-NP (50 nm) on Hep G2 cells. Nanoparticles are containing high surface area to volume ratio that converted them to reactive molecules; therefore we evaluated oxidative stress biomarkers such as reactive oxygen species (ROS), lactate dehydrogenase leakage (LDH) and cell death by standard biochemical methods. Assessment of ROS content in a different concentration of Fe2O3-NP approved increased ROS level (up to 3.2 folds) concentration-dependent manner. ROS overproduction is accompanied by LDH leakage from the cells (4 folds than control) possibly caused by membrane damages in the presence of toxicant nanoparticle. Mentioned molecular effects increase cell death by more than 80% in a dosedependent manner that evaluated by MTT assay. Possibly due to the small size of nanoparticle which allows fast and easy entry into the cells and increased ROS overproduction that attack to the membrane and intracellular organelles, the viability of cells significantly decreased in the presence of nanoparticle.

Nanoparticles, Reactive oxygen species, Lactate dehydrogenase leakage, Membrane injury, Apoptosis