Size-Dependent Cytotoxicity and Multi-Omic Changes Induced by Amorphous Silicon Nanoparticles in HepG2 Cells

Area of Science:

• Nanotechnology
• Toxicology
• Biochemistry

Background:

• Silica nanoparticles (SiO2 NPs) pose a significant human exposure risk, with a tendency to accumulate in the liver.
• Understanding the in vitro toxicological effects and molecular mechanisms of SiO2 NPs is crucial due to potential health implications.

Purpose of the Study:

• To investigate the size-dependent cytotoxicity of SiO2 NPs on human hepatoma cells (HepG2).
• To identify key molecular pathways affected by SiO2 NPs exposure using multi-omics approaches (proteomics and metabolomics).

Main Methods:

• HepG2 cells were exposed to varying concentrations of 60, 250, and 400 nm SiO2 NPs for 24 hours.
• Proteomics and metabolomics analyses were employed to assess cellular responses and identify affected pathways.

Main Results:

• Cytotoxicity was size-dependent, with 60 nm SiO2 NPs causing greater reduction in cell viability.
• Metabolomic and proteomic profiles showed significant, size-dependent alterations.
• Key affected pathways included cholesterol metabolism (proteomics) and central carbon metabolism (metabolomics), particularly for 60 nm NPs.

Conclusions:

• SiO2 NP exposure induces size-dependent cytotoxicity and molecular pathway alterations in liver cells.
• Interference with energy metabolism pathways is a probable mechanism underlying SiO2 NP toxicity.
• Combined omics data revealed common affected pathways like protein and vitamin digestion and absorption.