The effect of protein corona of Zinc oxide nanoparticles on CHO cells plasma membrane permeability and mitochondrial membrane potential

Abstract

Nowadays nanoparticles (NPs) are exciting object for researchers due to their properties and wide application. Nanoscale materials are used in cosmetic products, sun protection, food area, paint production, electronics, medicine etc. As the use of nanomaterials increase worldwide, the risk on human health and environmental increases. It is, therefore, necessary to assess the potential adverse effects of exposure and their mechanisms in cells. Futhermore, the nanoparticles are coated by proteins and other biomolecules when entering living organism and these surface modifications may have enormous influence to NPs fate and its bioeffects. In this study ZnO NPs coating with protein, also known as protein corona, was formed from model protein bovine serum albumin (BSA). The aim of this study was to evaluate the effect of ZnO NPs coating with albumin (ZnO-BSA NPs) on Chinese hamster ovary (CHO) cell viability, proliferation, plasma membrane permeability and mitochondrial membrane potential. We have demonstrated that in the concentration range 0.1-10 g/ml ZnO NPs have stimulating effect on CHO cells viability (after 3h incubation) determined by MTT assay and proliferation (after 24h incubation) determined by staining with crystal violet. At higher concentrations (25-200 g/ml) cell viability decreased in a concentration-dependent manner and reached minimal viability of 55% at 150 g/ml as compared to control. The effect of ZnO NPs on cell proliferation followed the same trend except that decrease was more pronounced and reached 60% already at 25 g/ml. Plasma membrane permeability induction may play an important role in NPs-induced cell death. We have applied lactate dehydrogenase (LDH) leakage test for plasma membrane permeability evaluation. LDH activity in the cell medium increased linearly increasing NPs concentration and reached 5-fold higher level as compared to control. ZnO-BSA NPs induced higher permeability as compared to plain ZnO NPs.[...]