Gold nanoparticles exposure modulates antioxidant and innate immune gene expression in the gills of Sparus aurata.

This study aimed to assess antioxidant and immune gene transcription alterations in the gills of Sparus aurata exposed during 96 h to 4, 80, and 1600 μg/L of gold nanoparticles (AuNPs) coated with citrate or polyvinyl pyrrolidone (PVP). After 96 h of exposure, gr and cat mRNA levels decreased for all tested concentrations of AuNPs, for both coatings. Instead, gst3 mRNA increased after exposure to 1600 μg/L AuNPs (both coatings) and prdx6 increased after exposure to 1600 μg/L AuNPs-citrate. Concerning immune genes, il1β mRNA levels increased after exposure to 80 μg/L AuNPs-citrate and 1600 μg/L AuNPs-PVP and cox2 mRNA showed increased levels in fish exposed to 1600 μg/L AuNPs-citrate. Results indicate that AuNPs with distinct coatings induced different gene expression profiles in gills, though most of the studied genes remained unaltered for the tested conditions.