Laboratory of ecological immunology of aquatic organisms, A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Lenninsky ave, 38, 119991 Moscow, Russia.
Department of Animal Physiology and Biochemistry, A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Lenninsky ave, 38, 119991 Moscow, Russia.
Comp Biochem Physiol B Biochem Mol Biol. 2023 Feb-Mar;264:110810. doi: 10.1016/j.cbpb.2022.110810. Epub 2022 Nov 4.
This study describes the analysis of antioxidant enzymatic activities (catalase and superoxide dismutase) in gills and functional state of hemocytes (osmotic stability, mitochondrial membrane potential) of ark clams (Anadara kagoshimensis) from the Black Sea basin exposed to salinity stress. For this, the effects of 48 h periods of exposure to low (8 ‰, 14 ‰) and high (35 ‰, 45 ‰) salinity were assessed. Our results showed that ark clams, A. kagoshimensis, possessed pronounced tolerance to hypersalinity stress and are sensitive to a short-time hyposalinity treatment. Salinity 35 ‰ inhibited production of reactive oxygen species (ROS) by hemocytes and did not affect their levels of mitochondrial membrane potential. Acclimation to 45 ‰ salinity caused significant increase in mitochondrial membrane potential accompanied with recovery of intracellular ROS levels up to controls levels. Acclimation to low salinity (8 ‰) induced an increase in both ROS and mitochondrial membrane potential levels in hemocytes. Catalase and superoxide dismutase activity in gills decreased following acclimation to low (8 ‰) and high (35 ‰) salinity. Exposure to the highest salinity levels (45 ‰) led to a decrease of superoxide dismutase activity levels, but did not influence the levels of catalase activity. Acclimation to low and high salinity was not accompanied with changes in osmotic fragility of hemocytes despite osmotic fragility curve according to changes in hemolymph osmolarity. Based upon these results, we postulate the involvement of cellular osmoregulatory mechanisms in the adaptation of the ark clam to short-term fluctuations of environmental salinity.
本研究描述了黑海盆地的阿那达蛤（Anadara kagoshimensis）在暴露于盐度胁迫下，鳃中抗氧化酶活性（过氧化氢酶和超氧化物歧化酶）和血淋巴细胞功能状态（渗透稳定性、线粒体膜电位）的分析。为此，评估了暴露于低（8‰、14‰）和高（35‰、45‰）盐度 48 小时的影响。我们的结果表明，阿那达蛤对高盐度胁迫具有明显的耐受性，对短时间低盐度处理敏感。盐度 35‰抑制了血淋巴细胞产生活性氧（ROS），但不影响其线粒体膜电位水平。适应 45‰盐度会导致线粒体膜电位显著增加，同时使细胞内 ROS 水平恢复到对照水平。适应低盐度（8‰）会导致血淋巴细胞中 ROS 和线粒体膜电位水平均升高。鳃中的过氧化氢酶和超氧化物歧化酶活性在适应低（8‰）和高（35‰）盐度后均下降。暴露于最高盐度水平（45‰）会导致超氧化物歧化酶活性水平降低，但不影响过氧化氢酶活性水平。尽管血淋巴渗透压变化，但适应低盐度和高盐度并不伴随血淋巴细胞渗透脆性的变化，根据渗透脆性曲线。根据这些结果，我们推测细胞渗透调节机制参与了阿那达蛤对环境盐度短期波动的适应。
