低盐驯化对急性低盐胁迫下大黄鱼能量代谢和线粒体自噬的影响机制  

Mechanistic studies on the effect of low-salinity acclimation on energy metabolism and mitophagy of Larimichthys crocea under acute low-salinity stress

作　　者：吉群 曾霖 熊逸飞 王永红 宋炜[1,3] JI Qun;ZENG Lin;XIONG Yifei;WANG Yonghong;SONG Wei(East China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Shanghai 200090,China;School of Food and Biological Engineering,Bengbu University,Bengbu 233030,China;College of Fisheries and Life Sciences,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]中国水产科学研究院东海水产研究所,上海200090 [2]蚌埠学院食品与生物工程学院,安徽蚌埠233030 [3]上海海洋大学水产与生命学院,上海201306

出　　处：《中国水产科学》2024年第10期1141-1150,共10页Journal of Fishery Sciences of China

基　　金：国家重点研发计划项目(2022YFD2401102);青岛海洋科技中心山东省专项经费项目(2022QNLM30001);中国水产科学研究院基本科研业务费项目(2020TD76)。

摘　　要：为探究低盐驯化对低盐胁迫下大黄鱼(Larimichthys crocea)能量代谢和线粒体自噬的影响机制,将体重为(53.46±1.47)g大黄鱼幼鱼从自然海水(盐度25)转移到盐度20的水体中驯化7 d后在低盐(盐度12)水体中暴露24 h。结果表明,低盐胁迫增加了活性氧(reactive oxygen species,ROS)和三磷酸腺苷(adenosine triphosphate,ATP)含量,提高了三羧酸循环酶活力和线粒体自噬基因表达水平,表明低盐胁迫增强了大黄鱼有氧代谢和线粒体自噬,但仍遭受氧化损伤。与低盐组相比,低盐驯化+低盐组提高了ATP含量、三羧酸循环酶活力和线粒体自噬基因表达水平,降低了ROS含量,表明低盐驯化通过改善低盐胁迫下大黄鱼的能量代谢和线粒体自噬来降低氧化损伤。在低盐胁迫过程中,腺苷酸活化蛋白激酶[adenosine 5’-monophosphate(AMP)-activated protein kinase,AMPK]与三羧酸循环酶和脂肪酸β氧化酶活力成正相关,与脂肪合成酸成负相关,表明大黄鱼通过AMPK来促进产能代谢,抑制耗能代谢,从而改善能量代谢效率。叉头框转录因子O亚型3(forkhead box class O3,FoxO3)与线粒体自噬基因表达水平呈正相关,表明FoxO3在低盐适应过程中参与了线粒体自噬基因表达的调控。以上结果说明,低盐驯化改善了有氧代谢和线粒体自噬,抑制了脂类合成,从而增强了大黄鱼对低盐胁迫的耐受性。The large yellow croaker(Larimichthys crocea)is one of the most economically important marine fish species in China.Reducing water salinity can effectively prevent white spot disease,but it can also cause low-salinity stress and damage to fish.Low-salinity acclimation can improve the body's tolerance to low salinity;therefore,it is necessary to explore the specific physiological mechanisms of low-salinity acclimation in fish under low-salinity stress.This study aimed to investigate the effects of low-salinity acclimation on energy metabolism and mitophagy in the large yellow croaker under low-salinity stress.Juvenile large yellow croakers with a body weight of(53.46±1.47)g were transferred from natural seawater(salinity 25)to water with a salinity of 20 and were cultured for 7 d and then exposed to low-salinity(salinity 12)water for 24 h.The results showed that low-salinity stress increased reactive oxygen species(ROS),adenosine triphosphate(ATP)content,tricarboxylic acid(TCA)cycle enzyme activities,and mitophagy gene expression levels,indicating that L.crocea improved aerobic metabolism and mitophagy under low-salinity stress but still suffered from oxidative damage.Compared with the low-salinity group,the low-salinity acclimation with low-salinity group showed increased ATP content,TCA enzyme activities,and mitophagy gene expression levels but reduced ROS content,indicating that low-salinity acclimation reduced oxidative damage by improving energy metabolism and mitophagy in large yellow croaker under low-salinity stress.During low-salinity stress,adenosine 5’-monophosphate(AMP)-activated protein kinase(AMPK)activity was positively correlated with TCA and fatty acidβoxidation enzyme activities and negatively correlated with fatty acid synthesis enzyme activity,indicating that AMPK promoted energy-yielding metabolism and inhibited energy-consumptive metabolism in L.crocea,thereby improving energy generation efficiency.Forkhead box class O3(FoxO3)mRNA levels were positively correlated with the expression leve

关 键 词：大黄鱼 低盐驯化 急性低盐胁迫 线粒体自噬 能量代谢 

分 类 号：S917[农业科学—水产科学]