TY - JOUR
T1 - Energy metabolism of juvenile scallops Nodipecten subnodosus under acute increased temperature and low oxygen availability
AU - Salgado-García, Rosa L.
AU - Kraffe, Edouard
AU - Tripp-Valdez, Miguel A.
AU - Ramírez-Arce, Jose L.
AU - Artigaud, Sebastien
AU - Flye-Sainte-Marie, Jonathan
AU - Mathieu-Resuge, Margaux
AU - Sicard, M. Teresa
AU - Arellano-Martínez, Marcial
AU - Racotta, Ilie S.
N1 - Publisher Copyright:
© 2023 Elsevier Inc.
PY - 2023/4
Y1 - 2023/4
N2 - High temperature increases energy demand in ectotherms, limiting their physiological capability to cope with hypoxic events. The present study aimed to assess the metabolic tolerance of juvenile Nodipecten subnodosus scallops to acute hyperthermia combined with moderate hypoxia. A previous study showed that juveniles exhibited a high upper temperature limit (32 °C), but the responses of juveniles to combined hyperthermia and low dissolved oxygen are unknown. Scallops were exposed to control conditions (treatment C: 22 °C, ∼7.1 mg O2 L−1 or PO2 156.9 mmHg), acute hyperthermia under normoxia (treatment T: 30 °C, ∼6.0 mg O2 L−1 or PO2 150.9 mmHg) or acute hyperthermia plus hypoxia (treatment TH: 30 °C, ∼2.5 mg O2 L−1 or PO2 62.5 mmHg) for 18 h. In T, juveniles exhibited an enhanced oxygen consumption, together with a decrease in adenylate energy charge (AEC) and arginine phosphate (ArgP), and with no changes in metabolic enzyme activity in the muscle. In TH, scallops maintained similar AEC and ArgP levels in muscle as those observed in T treatment. This response occurred along with the accumulation of inosine monophosphate and hypoxanthine. Besides, reduced citrate synthase and pyruvate kinase activities, enhanced hexokinase activity, and a higher octopine dehydrogenase/lactate dehydrogenase ratio in the mantle indicated the onset of anaerobiosis in TH. These responses indicate that juvenile scallops showed tissue-specific compensatory responses regarding their energy balance under moderate hypoxia at high temperatures. Our results give an insight into the tolerance limit of this species to combined hyperthermia and hypoxia in its northern limit of distribution.
AB - High temperature increases energy demand in ectotherms, limiting their physiological capability to cope with hypoxic events. The present study aimed to assess the metabolic tolerance of juvenile Nodipecten subnodosus scallops to acute hyperthermia combined with moderate hypoxia. A previous study showed that juveniles exhibited a high upper temperature limit (32 °C), but the responses of juveniles to combined hyperthermia and low dissolved oxygen are unknown. Scallops were exposed to control conditions (treatment C: 22 °C, ∼7.1 mg O2 L−1 or PO2 156.9 mmHg), acute hyperthermia under normoxia (treatment T: 30 °C, ∼6.0 mg O2 L−1 or PO2 150.9 mmHg) or acute hyperthermia plus hypoxia (treatment TH: 30 °C, ∼2.5 mg O2 L−1 or PO2 62.5 mmHg) for 18 h. In T, juveniles exhibited an enhanced oxygen consumption, together with a decrease in adenylate energy charge (AEC) and arginine phosphate (ArgP), and with no changes in metabolic enzyme activity in the muscle. In TH, scallops maintained similar AEC and ArgP levels in muscle as those observed in T treatment. This response occurred along with the accumulation of inosine monophosphate and hypoxanthine. Besides, reduced citrate synthase and pyruvate kinase activities, enhanced hexokinase activity, and a higher octopine dehydrogenase/lactate dehydrogenase ratio in the mantle indicated the onset of anaerobiosis in TH. These responses indicate that juvenile scallops showed tissue-specific compensatory responses regarding their energy balance under moderate hypoxia at high temperatures. Our results give an insight into the tolerance limit of this species to combined hyperthermia and hypoxia in its northern limit of distribution.
KW - Bivalve
KW - Growth
KW - Hypoxia
KW - Tolerance
KW - Warming
UR - http://www.scopus.com/inward/record.url?scp=85146667311&partnerID=8YFLogxK
U2 - 10.1016/j.cbpa.2023.111373
DO - 10.1016/j.cbpa.2023.111373
M3 - Artículo
C2 - 36690296
AN - SCOPUS:85146667311
SN - 1095-6433
VL - 278
JO - Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology
JF - Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology
M1 - 111373
ER -