Gene expression profiling associated with treatment of positive charged colloidal silica nanoparticle in human neuroblastoma cells

Abstract

Among the physico-chemical properties of nanoparticles, surface chemistry is one of the most important factors in cytotoxicity or cellular injurious effects of nanoparticles. However, the role of specific surface chemistry involved in the intracellular responses is not well understood. We investigated the comprehensive gene expression profile of biological responses of commercially available colloidal silica nanoparticles with different charge in human neuronal cell line, SHSY5Y. Positive charged silica CL nanoparticle showed less cytotoxicity than negative charged silica AM at more than 200 ppm. At 100 ppm, however, both positive and negative charged silica nanoparticles gave rise to low cytotoxicity. On the other hand, transcriptional changes by these silica nanoparticles represented that positive charged silica CL affected to much more genes than negative charged silica AM. Through gene ontology (GO) analysis, we identified that positive charged silica CL nanoparticle affected to the receptor mediated cellular responses, organization of cytoskeleton like as actin and regulation of transcription by ribosomal proteins or transcription factors. Unlike to negative charged silica nanoparticles, positive charged silica CL nanoparticle did not affect to sterol metabolism and lipid transport. Especially, some cell junction related genes (CTNNA1, PTPRM, CLDN19 and CTNNA1) were differentially expressed by positive charged silica nanoparticle, and these genes may be involved in interaction between the positive charged nanoparticle and molecules with negative charge present in cellular membrane. Thus, we suggest that specific surface charge of silica nanoparticle may be an important point being considered when assesses the safety of silica nanoparticles in neuronal cells.