Functional changes in hemocytes and antioxidant activity in gills of the ark clam Anadara kagoshimensis (Bivalvia: Arcidae) induced by salinity fluctuations

Short-time salinity fluctuations are strong activators of oxidative stress in Mediterranean mussel (Mytilus galloprovincialis)

“…The results of the present study are in line with our previous work demonstrating loss of CAT and SOD activity in gills and enhanced ROS production by hemocytes of other bivalve species, A. kagoshimensis exposed to hyposaline conditions (8 ‰) (Kladchenko et al, 2023). Similarly, hyposalinity stress impacted SOD activity and promoted ROS production in R. philippinarum (15‰) (Nie et al, 2020), V. philippinarum, V. decussata и V. corrugate (0 and 7 ‰) (Carregosa et al, 2014), Magallana hongkongensis (Lam & B. Morton, 2003) (8 ‰) (Wei et al, 2022b).…”

“…As demonstrated in this study a decrease of environmental salinity was not associated with recovery of the activity of antioxidant enzymes, as it was shown for mussels exposed to 30 ‰ salinity. We found this tendency in our recent work on A. kagoshimensis that also showed increased ROS levels in hemocytes and loss of CAT and SOD activity in gills upon acclimation to low salinity, whereas exposure high salinity did not significantly affect the antioxidant status of the organism (Kladchenko et al, 2023). Similar conclusions were made for oysters Pinctada maxima (Jameson, 1901) exposed to high and low salinity (Wei et al, 2022a).…”

“…In the present work increased ROS content could affect the activity of SOD and CAT in gills of mussels. Recent findings have been demonstrated similar loss of the antioxidant capacity for other bivalve species exposed to hypersaline environment: SOD activity decreased in Pinctada maxima (Jameson, 1901) (under 40‰) (Wei et al, 2022b) and in gills of A. kagoshimensis (under 45‰) (Kladchenko et al, 2023). Losses of SOD and CAT activity were also reported for Pinctada fucata (Jameson, 1901) upon exposure to 50 ‰ (Sun et al, 2021).…”

“…In case of short-time salinity fluctuations oxidative stress occurs even if the range of salinity changes does not exceed species distribution potential. Similarly, in Anadara kagoshimensis (Tokunaga, 1906) low salinity (8 ‰) enhanced ROS formation in hemocytes, whereas salinization (35 ‰ and 45 ‰) inhibited ROS synthesis in hemocytes (Kladchenko et al, 2023).…”

“…Although the effects of salinity on OS markers and the antioxidant status of the whole organism have been demonstrated for a number of marine bivalves (Freitas et al, 2017;Kladchenko et al, 2023;Wei et al, 2022b), our knowledge on the interaction between ROS production in cells upon osmoregulation and the general response of the antioxidant system to slow changes of environmental salinity is lacking for euryhaline species. The effect of salinity fluctuations on ROS production in cells of osmoconformers is still under debate.…”