文献类型：期刊文献

英文题名：Effects of hypoxia stress on digestive enzyme activities, intestinal structure and the expression of tight junction proteins coding genes in juvenile cobia (Rachycentron canadum)

作者：Yang, Er-Jun[1];Zhang, Jian-Dong[1,2,3];Yang, Lin-Tong[1];Amenyogbe, Eric[1];Wang, Wei-Zheng[1];Huang, Jian-Sheng[1,2,3];Chen, Gang[1,2,3]

机构：[1]Guangdong Ocean Univ, Fishery Coll, Zhanjiang 524025, Peoples R China;[2]Southern Marine Sci & Engn Guangdong Lab Zhanjian, Zhanjiang, Peoples R China;[3]Guangdong Prov Key Lab Pathogen Biol & Epidemiol, Zhanjiang, Peoples R China

年份：2021

卷号：52

期号：11

起止页码：5630

外文期刊名：AQUACULTURE RESEARCH

收录：SCI-EXPANDED(收录号：WOS:000669836900001)、、WOS

基金：This work was supported by grants from China Agriculture Research System (CARS-47); Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang)(ZJW-2019-06)].

语种：英文

外文关键词：digestive enzymes; hypoxia stress; intestine; Rachycentron canadum; tight junction proteins

外文摘要：In this study, juvenile cobia fish (Rachycentron canadum) (body weight: 50.44 +/- 2.78 g) were used as a study object to investigate the effects of hypoxia stress (dissolved oxygen: 3.15 +/- 0.21 mg/L) on the activities of their digestive enzymes, intestinal morphology and relative expression of tight junction proteins coding genes. Under the experimental conditions, the juvenile cobia were given 28 days of hypoxia stress. The results showed that the activities of digestive enzymes in the intestines of the hypoxia stress group decreased. In addition, the amylase and lipase activities decreased significantly (p < 0.05), and the trypsin activity in the hypoxia stress group compared to that in the control group. The morphology and structure of the intestine also showed significant changes. Under the microscopic observation, the mucosal fold height and muscle thickness of the intestine showed a significant decrease (p < 0.05); also, the villi's width showed a significant decrease (p < 0.05) in the hypoxia stress group as compared to that in the control group. The observation under a transmission electron microscope showed that the microvilli of juvenile cobia in the hypoxia stress group were irregularly arranged, atrophied and fallen off compared to the control group. Furthermore, there were gaps in the tight junction. In addition, the boundary between cells was unclear. The relative expression of intestinal tight junction proteins coding genes was down-regulated to varying degrees. The mRNA expressions of ZO-1 and claudin-4 were significantly down-regulated (p < 0.05) and ZO-2 and occludin in the hypoxia stress group compared to those in the control group. These results indicated that hypoxia stress could inhibit the activities of intestinal digestive enzymes, damage intestinal morphology and decrease the expression of tight junction proteins coding genes in cobia. The present study provided a scientific foundation for evaluating the multifaceted impacts of hypoxia stress on fish species, such as cobia.