Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, Key Laboratory of Fishery Ecology and Environment, Guangdong Province, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China.
Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture, Key Laboratory of Fishery Ecology and Environment, Guangdong Province, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, PR China.
J Invertebr Pathol. 2018 Mar;153:186-194. doi: 10.1016/j.jip.2018.03.003. Epub 2018 Mar 9.
The shrimp intestine barrier serves as the first line of the host defense against pathogen infection. Lipopolysaccharide (LPS) is the cell wall component of gram-negative bacteria, which known as endotoxin and induce the intestine inflammation. In this study, the acute toxicity effects of LPS injection on the morphology, digestive enzymes and immunological responses of intestine from Litopenaeus vannamei was investigated. HE stain showed that LPS injection damaged the intestine connective and epithelium tissue. Specifically, a decrease in the activities of digestive enzymes including of amylase, lipase, trypsin and pepsin was observed. Moreover, LPS injection increased the content of oxidative stress parameters (O generation capacity, LPO, MDA and PC), and the expression of HIF-1α gene. Alternatively, the antibacterial activities (PO and T-NOS), and the expression of the antibacterial genes (proPO, ALF, Toll and Imd) and pathogen pattern recognition genes (LGBP and Lec) increased at first and then decreased. Significant variations in anitioxidant enzyme activity of T-AOC, and the expression of the anitioxidant-related genes (SOD, HSP70 and Trx). These results revealed that LPS injection harmed the intestine barrier of L. vannamei by damaging intestine mucosal structure, increasing oxidative stress, and suppressing the digestive and immune status.
虾的肠道屏障是宿主抵御病原体感染的第一道防线。脂多糖（LPS）是革兰氏阴性菌的细胞壁成分，被称为内毒素，可引发肠道炎症。在本研究中，研究了 LPS 注射对凡纳滨对虾肠道形态、消化酶和免疫反应的急性毒性作用。HE 染色显示 LPS 注射破坏了肠道结缔组织和上皮组织。具体来说，观察到淀粉酶、脂肪酶、胰蛋白酶和胃蛋白酶等消化酶活性降低。此外，LPS 注射增加了氧化应激参数（O 生成能力、LPO、MDA 和 PC）和 HIF-1α 基因的表达。相反，抗菌活性（PO 和 T-NOS）以及抗菌基因（proPO、ALF、Toll 和 Imd）和病原体模式识别基因（LGBP 和 Lec）的表达先增加后减少。T-AOC 的抗氧化酶活性和抗氧化相关基因（SOD、HSP70 和 Trx）的表达也发生了显著变化。这些结果表明，LPS 注射通过破坏肠道黏膜结构、增加氧化应激和抑制消化和免疫状态来损害凡纳滨对虾的肠道屏障。
