Microarray analysis of gene expression differences in microglia after exposure to graphene quantum dots

Area of Science:

• Nanomaterials toxicology
• Neuroscience
• Molecular biology

Background:

• Graphene quantum dots (GQDs) show promise in biomedicine but may pose risks to the central nervous system (CNS).
• The precise mechanisms underlying GQD neurotoxicity remain unclear, necessitating further investigation.

Purpose of the Study:

• To elucidate the biological mechanisms of neurotoxicity induced by nitrogen-doped GQDs (N-GQDs) and amino-functionalized GQDs (A-GQDs).
• To identify key cellular pathways and molecular events involved in GQD-induced neurotoxicity using genome-wide transcription analysis.

Main Methods:

• Genome-wide transcription microarray analysis of BV2 cells treated with N-GQDs and A-GQDs.
• Gene Ontology (GO) and KEGG pathway analyses to identify enriched functions and signaling pathways.
• Validation using qRT-PCR, Western blot, intracellular calcium measurements, and comet assays.

Main Results:

• Significant alterations in gene expression were observed in BV2 cells treated with both N-GQDs and A-GQDs.
• Key affected pathways included calcium signaling, cell cycle regulation, and endocytosis.
• Experimental validation confirmed calcium dyshomeostasis, DNA damage, and cell cycle arrest as critical factors in GQD neurotoxicity.

Conclusions:

• GQD neurotoxicity is mediated by disruptions in calcium homeostasis, DNA integrity, and cell cycle progression.
• These toxic effects are linked to specific signaling pathways, regardless of GQD functionalization.
• This study provides essential data for understanding GQD neurotoxicity mechanisms and ensuring their safe application.