饥饿复投喂对长江鲟肝脏、肠道和肌肉抗氧化功能的影响.docx

    饥饿复投喂对长江鲟肝脏、肠道和肌肉抗氧化功能的影响    吴晓雲 陈叶雨 赖见生 刘亚 宋明江 龚全摘要：【目的】明確饥饿与复投喂对长江鲟肝脏、肠道和肌肉抗氧化功能的影响，为揭示其对环境胁迫的生理适应机制提供参考依据方法】选取120尾体重相近（60.532±0.284 g）、健康、活力好的长江鲟随机分为4个处理组，分别进行0、3、7和14 d饥饿再复投喂14 d，试验结束后检测长江鲟肝脏、肠道和肌肉的各项抗氧化指标，包括丙二醛（MDA）含量、蛋白质羰基（PC）含量、超氧化物歧化酶（SOD）活性、过氧化氢酶（CAT）活性、谷胱甘肽硫转移酶（GST）活性、谷胱甘肽过氧化物酶（GSH-Px）活性、谷胱甘肽还原酶（GR）活性、谷胱甘肽（GSH）活性及抗超氧阴离子（ASA）和抗羟基自由基（AHR）能力结果】在饥饿期间，长江鲟肝脏MDA含量、GST活性、GSH-Px活性和GR活性均随饥饿胁迫时间的延长显著下降（P<0.05，下同）;肠道GR活性和GSH活性也随饥饿胁迫时间的延长逐渐下降，MDA含量呈先升高后下降的变化趋势，CAT活性、GST活性和GSH-Px活性则先下降后上升;肌肉MDA含量和PC含量呈先显著升高后下降的变化趋势，CAT活性以饥饿14 d后最高，GR活性、GSH活性及ASA能力均无显著差异（P>0.05，下同）。

复投喂后，长江鲟肝脏GSH-Px活性呈显著下降趋势，GR活性的变化趋势与GSH-Px活性恰好相反;肠道PC含量随饥饿胁迫时间的延长而显著下降，CAT活性、GST活性、GSH-Px活性和GR活性则先升高后降低，说明其肠道抗氧化能力在饥饿7 d复投喂14 d后显著上调;肌肉MDA含量、PC含量、SOD活性和AHR能力均呈显著下降趋势，CAT活性、GST活性和GR活性则以饥饿14 d复投喂14 d的最高结论】饥饿会抑制长江鲟体内抗氧化能力，随着饥饿胁迫时间的延长，其体内通过调动不同抗氧化酶活性逐渐形成新的氧化平衡以维持正常生理状态;复投喂后由于营养物质得到补充，促使鱼体各项生理机能得到恢复，一定程度上缓解饥饿产生的氧化应激并形成新的氧化平衡关键词： 长江鲟;饥饿;复投喂;抗氧化酶;氧化平衡中国分类号： S965.219                              文献标志码： A ：2095-1191（2021）11-3157-09Effects of starvation and refeeding on antioxidative function of liver， intestine and muscle in Acipenser dabryanusWU Xiao-yun， CHEN Ye-yu， LAI Jian-sheng， LIU Ya，SONG Ming-jiang， GONG Quan*（Fishery Institute， Sichuan Academy of Agricultural Sciences/Observation and Research Station of Sichuan Province of Fish Resources and Environment in Upper Reaches of the Yangtze River， Chengdu  611713， China）Abstract：【Objective】In order to study the effects of starvation and refeeding on antioxidant function of liver， intestine and muscle in Acipenser dabryanus， so as to provide reference basis for revealing its physiological adaptation mechanism to environmental stress.【Method】One hundred and twentyhealthy and vigorous A.dabryanus with similar body weight（60.532±0.284 g）were randomly divided into four treatment groups for 0， 3， 7 and 14 d starvation and 14 d refee-ding test.After the experiment，the activities of antioxidant enzymes in liver， intestine and muscle were detected，including malondialdehyde（MDA） content and protein carbonyl（PC） content， superoxide dismutase（SOD） activity，catalase （CAT） activity， glutathione S-transferase （GST） activity， glutathione peroxidase （GSH-Px）activity，glutathione reductase（GR） activity and glutathione（GSH） activity and anti-superoxide anion（ASA） and anti-hydroxyl radical（AHR） ability. 【Result】During starvation， the results showed that the MDA content， GST， GSH-Px and GR activities in liver decreased significantly with prolonged starvation（P<0.05， the same below）; GR activity and GSH content in intestine decreased gradually with prolonged starvation， CAT， GST and GSH-Px activities decreased first and then increased， while the MDA content increased first and then decreased. MDA and PC content in muscle increased significantly at first and then decreased， the highest activity of CAT was observed in 14 dgroup， whilethere was no significant difference in GR，GSH and ASA activities（P>0.05，the same below）. After refeeding， GSH-Px activities in liver decreased significantly， the change trend of GR activity was opposite to that of GSH-Px; intestinal PC content decreased significantly with with prolonged starvation， CAT， GST， GSH-Px and GR activities increased first and then decreased，it showed that the intestinal antioxidant capacity was significantly up-regulated after 7 d of starvation and 14 d of refeeding; the content of MDA and PC， activities of SOD and AHR in muscle sinificantly decreased，where the CAT， GST and GR enzymes activities were the highestin14 d group. 【Conclusion】Starvation can inhibit the antioxidant capacity of A. dabryanus. With the extension of starvation stress time， a new oxidative balance is gradually formed by mobilizing different antioxidant enzyme activities to maintain the normal physiological state. After refeeding， nutrients are supplemented to restore the physio-logical functions of the fish， alleviate the oxidative stress caused by starvation to a certain extent， and form a new oxidative balance.Key words： Acipenser dabryanus; starvation; refeeding; antioxidant enzymes; oxidative balanceFoundation item：Sichuan Science and Technology Project（2021YFYZ0015）; Project of Key Laboratory of Sichuan Province for Fishes Conservation and Utilization in the Upper Reaches of the Yangtze River（NJTCCJSYSYS07）; Frontier Project of Sichuan Academy of Agricultural Sciences（2019QYXK021）;Sichuan Freshwater Fish Innovation Team Construction Project of National Modern Agricultural Industrial Technology System（2019-2023）0 引言【研究意義】长江鲟（Acipenser dabryanus）又称达氏鲟、沙腊子或小腊子，隶属于鲟形目（Acipense-riformes）鲟科（Acipenseridae），曾是长江上游重要的经济捕捞对象（刘亚等，2018），但由于过度捕捞、水体污染、海滩开垦及人类活动的干扰，从20世纪后期开始长江鲟自然种群资源规模急剧缩小，现已被列为国家一级重点保护野生动物（陈俊和徐承旭，2019;胡伟等，2020），并被世界自然保护联盟（IUCN）升级为极危级（GR）保护物种。

营养状况、免疫力和抗氧化能力间的动态平衡决定了鱼类抵抗疾病的生理能力（Feng et al.，2011;谢雨欣等，2018）在自然水域生态系统中，鱼类常因时间、空间、季节更替及环境变化导致食物短缺而受饥饿胁迫的影响（徐蕾，2019）饥饿胁迫过程中鱼类的抗氧化水平降低，易引起活性氧（Reactive oxygen species，ROS）侵袭，当细胞内ROS水平超过清除酶系统的处理能力则导致组织。