Seasonal monitoring of cellular energy metabolism in a sentinel species, Dreissena polymorpha (bivalve): Effect of global change?

Aquatic organisms such as bivalves are particularly sensitive to seasonal fluctuations associated with climate changes. Energy metabolism management is also closely related to environmental fluctuations. Changes in both biotic and abiotic conditions, such as the reproduction status and temperature respectively, may affect the organismenergy status. A bivalve sentinel species, Dreissena polymorpha was sampled along its one-year reproduction cycle in situ (2018-2019) to study naturalmodulations on severalmarkers of energy metabolismregarding seasonal variations in situ. A panel of different processes involved in energymetabolism was monitored through different functions such as energy balance regulation, mitochondrial density, and aerobic/anaerobic metabolism. The typical schema expected was observed in amajor part of measured responses. However, themonitored population of D. polymorpha showed signs ofmetabolismdisturbances caused by an external stressor from April 2019. Targeting a major part of energymetabolismfunctions, a global analysis of responses suggested a putative impact on the mitochondrial respiratory chain due to potential pollution. This study highlighted also the particular relevance of in situ monitoring to investigate the impacts of environmental change on sentinel species. (C) 2020 Elsevier B.V. All rights reserved.