Salinity stress from the perspective of the energy-redox axis: Lessons from a marine intertidal flatworm

摘要: In the context of global change, there is an urgent need for researchers in conservation physiology to understand physiological mechanisms leading acquisition stress acclimation phenotypes. Intertidal organisms continuously cope with drastic changes their environmental conditions, making them outstanding models study acclimation. As implementation such processes usually comes at a high bioenergetic cost, mitochondrial/oxidative approach emerges as most relevant when seeking analyze whole-animal responses. Here we use intertidal flatworm Macrostomum lignano bioenergetics salinity and its consequences terms reactive oxygen/nitrogen species formation response counteract redox imbalance. Measures water fluxes body volume suggest that M. hyper-/iso-regulator. Higher salinities were revealed be energetically expensive increase mitochondrial density accompanied by increased respiration rates. Such modifications came price enhanced superoxide anion production, likely associated caspase 3 upregulation. These animals nevertheless managed live levels through upregulation several antioxidant enzymes dismutase. Contrarily, low decreased rates, reduced activity nitric oxide formation, suggesting certain degree metabolic arrest. A contradictory dichlorofluorescein fluorescence gluthathione-S-transferase pi 1 (GSTP1) expression observed these individuals. If are indeed facing depression, return seawater may result oxidative burst. We hypothesize this GSTP1 could “preparation stress”, i.e. mechanism production free radicals upon returning seawater. The results present shed new light on how tolerant carry out subcellular adaptations withstand change.