Neuro-oxidative damage and aerobic potential loss of sharks under elevated CO2 and warming

作者：Rosa Rui^*; Paula Jose Ricardo; Sampaio Eduardo; Pimentel Marta; Lopes Ana R; Baptista Miguel; Guerreiro Miguel; Santos Catarina; Campos Derek; Almeida Val Vera M F; Calado Ricardo; Diniz Mario; Repolho Tiago

来源：Marine Biology, 2016, 163(5): 119.

DOI：10.1007/s00227-016-2898-7

Sharks occupy high trophic levels in marine habitats and play a key role in the structure and function of marine communities. Their populations have been declining worldwide by >= 90 %, and their adaptive potential to future ocean conditions is believed to be limiting. Here we experimentally exposed recently hatched bamboo shark (Chiloscyllium punctatum) to the combined effects of tropical ocean warming (+4; 30 degrees C) and acidification (Delta pH 0.5) and investigated the respiratory, neuronal and antioxidant enzymatic machinery responses. Thirty days post-hatching, juvenile sharks revealed a significant decrease in brain aerobic potential (citrate synthase activity), in opposition to the anaerobic capacity (lactate dehydrogenase). Also, an array of antioxidant enzymes (glutathione S-transferase, superoxide dismutase activity and catalase) acted in concert to detoxify ROS, but this significant upregulation was not enough to minimize the increase in brain's peroxidative damage and cholinergic neurotransmission. We argue that the future conditions may elicit deleterious deficiencies in sharks' critical biological processes which, at the longterm, may have detrimental cascading effects at population and ecosystem levels.

• 出版日期2016-5