Impaired antioxidant defenses and DNA damage in the European glass eel (Anguilla anguilla) exposed to ocean warming and acidification

The European eel (Anguilla anguilla) has attracted scientific inquiry for centuries due to its singular biological traits. Within the Union, glass fisheries have declined sharply since 1980, from up 2000 t (t) 62.2 in 2018, placing wild populations under higher risk of extinction. Among major causes eels collapse, climate change become a growing worldwide issue, specifically ocean warming and acidification, but, our knowledge, data on physiological biochemical responses these stressors is limited. this context, we selected some representative biomarkers [e.g. glutathione peroxidase (GPx), catalase (CAT), total antioxidant capacity (TAC), heat shock proteins (HSP70), ubiquitin (Ub) DNA damage] study distinct laboratory-climate scenarios, such as increased water temperature (+ 4 °C) pH reduction (? 0.4 units), 12 weeks. Overall, enzymatic machinery was impaired, both muscle viscera, manifested by significant changes CAT, GPx TAC. Heat response varied differently between tissues, increasing with muscle, but not decreasing tissues acidification. inability HSP maintain functional protein conformation responsible boosting production Ub, particularly sole stressors. overproduction reactive oxygen species (ROS), either elicited - metabolic demand or acidification through H+ interaction O2?, generating H2O2 overwhelmed defense mechanisms, causing oxidative stress consequently leading damage. Our results emphasize vulnerability eels' early life stages change, potential cascading consequences adult stocks.