School of Biological Sciences


While there is an increasing interest in using electromagnetic fields and nanomaterials to boost neuronal differentiation and/or protect neurons from oxidative stress, little is known about effects of their cells in vitro. We investigated the effect of external magnetic fields (alternating current (AC) and direct current (DC) MF) on the neuronal viability, differentiation, and neurite outgrowth of SH-SY5Y neuroblastoma human cells in vitro. This study indicated that low frequency and fields with weak strength AC MF, and fields with high strength DC MF improved the efficiency of retinoic acid mediated neuronal differentiation without any adverse effects on neuronal viability; as shown by increased length of neurites in SH-SY5Y neuroblastoma cells. The cell viability has not changed after AC MF exposure, and it had no real adverse effect on cell confluency after DC MF exposure; in fact, even without retinoic acid, AC and DC MF promoted neurite outgrowth in low serum conditions. This study has therefore identified a simple and cost-effective method for differentiating SH-SY5Y cells without expensive reagents. We also describe a novel DC MF source that is simple to apply and very efficient, in fact our results suggest that this DC MF system is better than AC MF with regards to the viability and differentiation of SH-SY5Y cells. This research is a new way of promoting neurite outgrowth in a commonly used neuronal-like cell line model. We also tested two different nanomaterials to assess their ability to protect SHSY5Y cells. We first tested the cytotoxic effect of oleic acid – coated and uncoated iron oxide (Fe3O4) NPs, and the cytotoxic impact of uncoated Yttrium oxide (Y2O3) NPs on the viability of neuroblastoma cells in vitro. The anti-oxidant impact of Yttrium oxide NPs was explored by checking whether or not it could reduce the oxidative stress induced by H2O2 in vitro on SH-SY5Y cells. This study also indicated that Yttrium oxide NPs could work as free radical scavengers to reduce the oxidative stress induced by hydrogen peroxide in SH-SY5Y cells in culture, however the protective effects were complex and depended on the concentration of nanoparticles and hydrogen peroxide used. This research provides a first step in understanding the effects that external magnetic fields and nanoparticles have on neuronal-like cells in culture. This combination of NPs guided by external magnetic field (AC or DC) should be considered in future research to exploit all the features of these nanomaterials and magnetic fields in neuronal differentiation and survival.



Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.