Salinity is an important environmental factor that affects the health of aquatic animals, when salinity level above the tolerance threshold can pose a significant threat to the survival of aquatic animals. As a trace element necessary for animal growth, selenium participates in the body’s antioxidant reaction, and protect aquatic animals from oxidative stress damage. Biological methods for synthesizing selenium nanoparticles (bio-Se-NPs) from bacteria are safe, inexpensive, and accessible. Therefore, we synthesized selenium nanoparticles using (probiotic) to study the growth, immune, antioxidant, and inflammatory responses of selenium-rich (SL, a type of bio-Se-NPs) fed under low-salinity (5 g/L salinity) and high-salinity (10 g/L salinity) stresses. Analyses revealed that the addition of SL at a concentration of 1 mg/kg significantly alleviated the growth inhibition caused by high-salinity stress. SL significantly alleviated salinity-induced liver tissue injury (numerous cytoplasmic vacuolations the accumulation, inflammatory cell infiltration, nuclear lysis, and some blood congestion). SL significantly alleviated the abnormal levels of serum ALT, AST, GGT and LDH caused by salinity stress, and improved lipid metabolism (TG, TC, LDL-C, HDL-C). SL can also regulates cytokines and antioxidant genes (TNF-α, iL-1β, iL-10, TGFβ-1, SOD, CAT, GPx1, and HO-1) through the NF-κB and Nrf-2 signaling pathways and thereby reduce the inflammatory response and increase the antioxidant level, and these effects attenuate salinity-mediated oxidative damage. In conclusion, our findings indicate that SL can significantly promote the growth and development of fish and alleviate the adverse effects of high-salinity stress and thus, SL can be a potential feed additive for alleviating oxidative stress and inflammatory responses.

中文翻译：

---

富硒植物乳杆菌缓解鲤鱼的盐度应激：生长性能、氧化应激以及免疫和炎症反应

盐度是影响水生动物健康的重要环境因素，当盐度水平超过耐受阈值时会对水生动物的生存构成重大威胁。硒作为动物生长必需的微量元素，参与机体的抗氧化反应，保护水产动物免受氧化应激损伤。从细菌中合成硒纳米粒子（bio-Se-NPs）的生物方法安全、廉价且容易获得。因此，我们使用（益生菌）合成硒纳米颗粒来研究低盐（5 g/L 盐度）下富硒（SL，一种生物硒纳米颗粒）的生长、免疫、抗氧化和炎症反应和高盐度（10 g/L 盐度）胁迫。分析表明，添加1 mg/kg的SL可显着缓解高盐胁迫引起的生长抑制。 SL显着减轻盐度引起的肝组织损伤（大量细胞质空泡堆积、炎性细胞浸润、核溶解和部分血液充血）。 SL显着缓解盐胁迫引起的血清ALT、AST、GGT和LDH异常水平，改善脂质代谢（TG、TC、LDL-C、HDL-C）。 SL还可以通过NF-κB和Nrf-2信号通路调节细胞因子和抗氧化基因（TNF-α、iL-1β、iL-10、TGFβ-1、SOD、CAT、GPx1和HO-1），从而降低炎症反应并增加抗氧化剂水平，这些作用减轻了盐度介导的氧化损伤。总之，我们的研究结果表明，SL可以显着促进鱼类的生长发育，减轻高盐胁迫的不利影响，因此，SL可以成为减轻氧化应激和炎症反应的潜在饲料添加剂。