In Vitro Toxic Effects of Zinc Oxide Nanoparticles on Rat Adipose Tissue-Derived Mesenchymal Stem Cells

Objective: Zinc oxide nanoparticles (ZnO-NPs) are increasingly used in sunscreens, bio-sensors, food additives, pigments, manufacture of rubber products, and electronic materials. There are several studies about the effects of NPs on dermal fibroblast or keratinocytes, but very little attention has been directed towards adipose-derived mesenchymal stem cells (ASCs). A previous study has revealed that ZnO-NPs restricted the migration capability of ASCs. However, the potential toxicity of these NPs on ASCs is not well understood. This study intends to evaluate the effects of ZnO-NPs on subcutaneous ASCs. Materials and Methods: In this experimental study, In order to assess toxicity, we exposed rat ASCs to ZnO-NPs at concentrations of 10, 50, and 100 mu g/ml for 48 hours. Toxicity was evaluated by cell morphology changes, cell viability assay, as well as apoptosis and necrosis detection. Results: ZnO-NPs concentration dependently reduced the survival rates of ASCs as revealed by the trypan blue exclusion and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium- bromide (MTT) tests. ZnO-NPs, at concentrations of 10 and 50 mu g/ml, induced a significant increase in apoptotic indices as shown by the annexin V test. The concentration of 10 mu g/ml of ZnO-NPs was more toxic. Conclusion: Lower concentrations of ZnO-NPs have toxic and apoptotic effects on subcutaneous ASCs. We recommend that ZnO-NPs be used with caution if there is a dermatological problem.