Targeting the Mild-Hypoxia Driving Force for Metabolic and Muscle Transcriptional Reprogramming of Gilthead Sea Bream (Sparus aurata) Juveniles

On-growing juveniles of gilthead sea bream were acclimated for 45 days to mild-hypoxia (M-HYP, 40–60% O2 saturation), whereas normoxic fish (85–90% saturation) constituted two different groups, depending on if they fed visual satiety (control fish) or pair-fed M-HYP fish. Following the hypoxia conditioning period, all maintained in normoxia and continued be until satiation 3 weeks. The time course hypoxia-induced changes was assessed by blood metabolic landmarks muscle transcriptomics before after exhaustive exercise a swim tunnel respirometer. In fish, our results highlighted higher contribution aerobic metabolism whole energy supply, shifting towards anaerobic fitness following restoration. Despite these substrate preference, shared persistent improvement swimming performance with critical speed at exhaustion. machinery contraction protein synthesis breakdown also largely altered conditioning, contributing this re-adjustment positive regulation locomotion catch-up growth response during recovery period. Altogether, reinforce presence large phenotypic plasticity bream, highlights as promising prophylactic measure prepare predictable stressful events.