Department of Biology, Faculty of Science, University of Guilan, Rasht, Iran.
Department of Biology, Faculty of Science, University of Guilan, Rasht, Iran; Department of Marine Sciences, The Caspian Sea Basin Research Center, University of Guilan, Rasht, Iran.
Mar Environ Res. 2023 Oct;191:106145. doi: 10.1016/j.marenvres.2023.106145. Epub 2023 Aug 15.
Changes in salinity is a stressful and energy-consuming process in fish which give rise to mortalities, especially in fish fingerlings that are more sensitive during the early stages of their life. In the present study, the effects of three salinities, 3‰ (downstream of river), 8‰ (estuarine), and 13‰ (the maximum salinity in the Caspian Sea), on HSP70 gene expression, cortisol level, immune response (lysozyme, complement C3, IgM), and antioxidant enzyme activities (SOD, CAT, T-AOC) of the stellate sturgeon fingerlings in the presence of HSP inducer compound (TEX-OE®) were evaluated. Our results showed that levels of plasma cortisol and heat shock protein (HSP70) in Acipenser stellatus fingerlings increased due to salinity changes. In the presence of the HSP inducer, HSP70 expression in both gill and liver was significantly increased, whereas cortisol level was notably decreased. Exposure to salinity changes resulted in an increase in antioxidant defense activities (SOD, CAT, and T-AOC) and immune response (lysozyme, IgM, and C3) in the presence of an HSP inducer. In conclusion, an HSP-inducing compounds can have a positive effect in strengthening the immunity and antioxidant system of sturgeon fingerlings by increasing the expression of the HSP70 gene against salinity fluctuations and generally increase the body's physiological tolerance.
盐度变化是鱼类的一种应激和耗能过程，会导致鱼类死亡，尤其是在生命早期阶段更为敏感的鱼苗中。在本研究中，评估了三种盐度（河流下游的 3‰、河口的 8‰和里海最大盐度的 13‰）对西伯利亚鲟鱼苗 HSP70 基因表达、皮质醇水平、免疫反应（溶菌酶、补体 C3、IgM）和抗氧化酶活性（SOD、CAT、T-AOC）的影响，同时存在 HSP 诱导剂化合物（TEX-OE®）。我们的结果表明，由于盐度变化，西伯利亚鲟鱼苗血浆皮质醇和热休克蛋白（HSP70）水平升高。在 HSP 诱导剂存在的情况下，鳃和肝脏中的 HSP70 表达显著增加，而皮质醇水平显著降低。暴露于盐度变化会导致抗氧化防御活性（SOD、CAT 和 T-AOC）和免疫反应（溶菌酶、IgM 和 C3）增加，而 HSP 诱导剂的存在则会增加。总之，HSP 诱导化合物可以通过增加 HSP70 基因的表达来增强西伯利亚鲟鱼苗的免疫力和抗氧化系统，从而对盐度波动产生积极影响，通常会提高机体的生理耐受性。
