TY - JOUR T1 - Osmoregulation and salinity-induced oxidative stress: is oxidative adaptation determined by gill function? A1 - Rivera-Ingraham,Georgina A. A1 - Barri,Kiam A1 - Boel,Melanie A1 - Farcy,Emilie A1 - Charles,Anne-Laure A1 - Geny,Bernard A1 - Lignot,Jehan-Herve AD - Univ Montpellier, Grp Fonctionnel AEO Adaptat Ecophysiol & Ontogene, UMR MARBEC 9190, Pl Eugene Bataillon, F-34095 Montpellier, France. AD - Univ Strasbourg, EA 3072, Federat Med Translat Strasbourg, 11 Rue Humann, F-67000 Strasbourg, France. UR - https://archimer.ifremer.fr/doc/00626/73816/ DO - 10.1242/jeb.128595 KW - Antioxidant defense KW - Carcinus aestuarii KW - ROS production KW - Osmoregulation N2 - Osmoregulating decapods such as the Mediterranean green crab Carcinus aestuarii possess two groups of spatially segregated gills: anterior gills serve mainly respiratory purposes, while posterior gills contain osmoregulatory structures. The co-existence of similar tissues serving different functions allows the study of differential adaptation, in terms of free radical metabolism, upon salinity change. Crabs were immersed for 2 weeks in seawater (SW, 37 ppt), diluted SW (dSW, 10 ppt) and concentrated SW (cSW, 45 ppt). Exposure to dSW was the most challenging condition, elevating respiration rates of whole animals and free radical formation in hemolymph (assessed fluorometrically using C-H(2)DFFDA). Further analyses considered anterior and posterior gills separately, and the results showed that posterior gills are the main tissues fueling osmoregulatory-related processes because their respiration rates in dSW were 3.2-fold higher than those of anterior gills, and this was accompanied by an increase in mitochondrial density (citrate synthase activity) and increased levels of reactive oxygen species (ROS) formation (1.4-fold greater, measured through electron paramagnetic resonance). Paradoxically, these posterior gills showed undisturbed caspase 3/7 activity, used here as a marker for apoptosis. This may only be due to the high antioxidant protection that posterior gills benefit from [superoxide dismutase (SOD) in posterior gills was over 6 times higher than in anterior gills]. In conclusion, osmoregulating posterior gills are better adapted to dSW exposure than respiratory anterior gills because they are capable of controlling the deleterious effects of the ROS production resulting from this salinity-induced stress. Y1 - 2016/01 PB - Company Biologists Ltd JF - Journal Of Experimental Biology SN - 0022-0949 VL - 219 IS - 1 SP - 80 EP - 89 ID - 73816 ER -