Tamoxifen induces biochemical responses in Pacific oysters Magallana gigas (Thunberg, 1793) at environmentally relevant concentrations.

• Published in: Marine Pollution Bulletin
• Main Authors: Paiva, Raphaella, Ferreira, Clarissa Pellegrini, Lima, Daína, Mattos, Jacó Joaquim, Pessatti, Tomás Bohn, Tisca, Juliana Fabrício, Saldaña-Serrano, Miguel, Nogueira, Diego José, Bebianno, Maria João, Bainy, Afonso Celso Dias
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier Science 2024
• Subjects: Antioxidant defense; Bivalve; Crassostrea gigas; Emergent contaminant; Mariculture
• Online Access: https://doi.org/10.1016/j.marpolbul.2024.116696; https://pubmed.ncbi.nlm.nih.gov/39042981

The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G6PDH), and glutathione-S-transferase (GST) were evaluated in the gills (GI) and digestive gland (DG) of Magallana gigas oysters exposed to tamoxifen (TAM) at environmental concentrations of 10 and 100 ng L-1 for 1 and 4 days. A higher CAT activity in the GI and DG and higher GPx activity only in the DG was observed of oysters exposed to both concentrations after 1 day. Furthermore, a significant increase in GR and G6PDH, was detected in the DG after 1 day of exposure to 10 ng L-1 and only G6PDH activity increase after 1 day of exposure to 10 ng L-1 in the GI. This suggests that the DG is a tissue more sensitive to TAM exposure and was confirmed with the individual Integrated Biomarker Response version 2 index (IBRv2i), highlighting the acute stress caused by TAM and a cellular adaptation.