Effect Of Gold Nanoparticles With Different Diameters On Rat Neural Stem Cells

Background:Neural stem cells(NSCs)are important cell lines for cell replacement therapy after nerve injury.In neuroscience research,how to direct induce the neural stem cells into neurons and oligodendrocytes is challenging.Gold nanoparticles(AuNPs)have unique physicochemical properties such as easy synthesis and biocompatibility.They are widely used in the biomedical field and have been used in many fields such as bioimaging,sensing,oncology treatment,and targeted drug delivery.Due to their unique size,AuNPs can freely pass through the blood-brain barrier.Studying the interaction between gold nanoparticles and neural stem cells can provide a new strategy for the treatment of neural stem cells.Objective:To investigate the effects of three sizes of AuNPs on the activity,proliferation and differentiation of neural stem cells at the cellular level.Methods:Using sodium borohydride reduction method to synthesis the 5nm-AuNPs and sodium citrate reduction method to synthesis 15nm and 50nm-AuNPs.Identified by transmission electron microscopy and uv-visible spectrometer.5%BSA was used to modify AuNPs.Immunofluorescence staining was performed on the cells extracted from the hippocampal area of newborn SD rats.The activity,proliferation and differentiation of NSCs were detected by adding different sizes of AuNPs to the cells in culture.Results:The transmission electron microscopy showed that AuNPs were spherical and uniform in size and dispersed uniformly in solution.Uv-visible spectra showed a single sharp absorption peak;The primary cells cultured by cell immunofluorescence staining were NSCs.Cell experiments show that 5nm-AuNPs can reduce cell activity,inhibit cell proliferation,polymerization,spherification and the differentiation of NSCs to neurons and glial cells.15nm-AuNPs can promote the differentiation of NSCs to neurons and 50nm-AuNPs can promote the differentiation of NSCs to glial cells.Conclusion:5nm-AuNPs have obvious cytotoxic effects on NSCs,15nm-AuNPs and 50nm-AuNPs can induce NSCs to neurons and glial cells.The size of the two nanoparticles may have neuroprotective effects.It is an important factor that size may causes three different kinds of AuNPs to produce different biological effects.This study enriches the value use of AuNPs and provides a new direction for the research of neural stem cells.