Seawater carbonate chemistry and enzymatic antioxidant defense, protein repair and removal of temperate shark (Scyliorhinus canicula)

• Main Authors: Pegado, Maria, Santos, Catarina P, Pimentel, Marta, Cyrne, Ricardo, Sampaio, Eduardo, Temporão, Ana, Röckner, Janina, Diniz, Mário, Rosa, Rui
• Format: Dataset
• Language: English
• Published: PANGAEA 2020
• Subjects: Alkalinity; total; standard deviation; Animalia; Aragonite saturation state; Benthos; Bicarbonate ion; Calcite saturation state; Calculated; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Catalase activity; per protein mass; Chordata; Coast and continental shelf; Containers and aquaria (20-1000 L or < 1 m**2); DNA damage; per protein; Experiment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Heat shock protein; Identification; Laboratory experiment; Lipid peroxidation; per wet mass; Nekton; North Atlantic; OA-ICC; Ocean Acidification International Coordination Centre; Organ; Other metabolic rates; Other studied parameter or process; Partial pressure of carbon dioxide; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.929859; https://doi.org/10.1594/PANGAEA.929859

Ocean acidification is a consequence of chemical changes driven mainly by a continuous uptake of carbon dioxide, resulting in pH decrease. This phenomenon represents an additional threat to marine life, with expected effects ranging from changes in behavioral responses and calcification rates to the potential promotion of oxidative stress. To unravel the impacts of ocean acidification on the antioxidant system of sharks, we performed a long-term exposure (9 months, since early embryogenesis) to high CO2 conditions (pCO2 900 μatm) on a temperate shark (Scyliorhinus canicula). The following biomarkers were measured: enzymatic antioxidant defense (superoxide dismutase, catalase and glutathione peroxidase), protein repair and removal (heat shock proteins and ubiquitin), and oxidative damage on lipids (malondialdehyde) and DNA (8-hydroxy-2′-deoxyguanosine). Changes in the antioxidant enzyme defense were restricted to an increase in catalase activity in the muscle, an enzyme that plays a major role in oxidative stress mitigation. On the other hand, no evidence of oxidative damage was found, indicating that the observed increase in catalase activity may be enough to neutralize the effects of potentially higher reactive oxygen species. These results further indicate that these sharks' antioxidant system can successfully cope with the levels of carbon dioxide projected for the end of the century. Nonetheless, the interaction between ocean acidification and the rise in temperature expected to occur in a near future may disturb their antioxidant capacity, requiring further investigation.