Wang Lin, Chen Hao, Xu Jianchao, Xu Qingsong, Wang Mengqiang, Zhao Depeng, Wang Lingling, Song Linsheng
Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian 116023, China.
Fish Shellfish Immunol. 2017 Mar;62:164-174. doi: 10.1016/j.fsi.2017.01.007. Epub 2017 Jan 9.
A robust immune response against invading pathogens is crucial for host to survive, which depends greatly on the well balance of metabolism. Increasing evidence has indicated that some metabolic hormones, such as insulin, could modulate immune responses directly. Crustacean hyperglycemic hormone (CHH) family is a group of ecdysozoans-specific peptide hormone involved in glucose metabolism and other biological events. In the present study, two members of CHH family (designated as LvCHH I and LvCHH II) in shrimp Litopenaeus vannamei with one and two crustacean neurohormone domains respectively were chosen to investigate their putative modulatory roles in both glucose metabolism and immune response. LvCHH I and LvCHH II were both expressed in the sinus gland and lamina ganglionalis of eyestalks and were significantly induced after white spot syndrome virus (WSSV) infection. Meanwhile, significant increases of hemolymph glucose levels were observed in shrimp at 12 and 24 h after WSSV infection while the glucose inside the hemocytes decreased at 6 h and then increased at 12 h. Gain-of-function of rLvCHHs was subsequently conducted in vivo by injecting the recombinant proteins (rLvCHH I and rLvCHH II). The hemolymph glucose increased significantly from 0.5 h to 3 h after the shrimps received an injection of rLvCHH I, while it decreased at 0.5 h and increased afterward at 3 h post rLvCHH II injection. At the meantime, significant decreases of reactive oxygen species level in hemocytes were observed at 3 h and 6 h post rLvCHH I injection, while it remained unchanged in rLvCHH II injection group. rLvCHH I and rLvCHH II could bind to the cytomembrane of primary shrimp hemocytes in vitro, and the expressions of superoxide dismutase and LvRelish increased when the hemocytes were incubated with rLvCHH I for 3 h. Meanwhile, the expression of antimicrobial peptides, crustin and penaeidin-4, were also induced by rLvCHH I and rLvCHH II. These results demonstrated that host immune response, in addition to glucose metabolism, could be directly modulated by LvCHH family, and the present study provided new insights into the immunomodulation role of metabolic hormones in invertebrate.
针对入侵病原体的强大免疫反应对宿主的生存至关重要，这在很大程度上取决于新陈代谢的良好平衡。越来越多的证据表明，一些代谢激素，如胰岛素，可以直接调节免疫反应。甲壳动物高血糖激素（CHH）家族是一组参与葡萄糖代谢和其他生物学事件的蜕皮动物特异性肽激素。在本研究中，选择凡纳滨对虾中分别具有一个和两个甲壳动物神经激素结构域的CHH家族的两个成员（命名为LvCHH I和LvCHH II），以研究它们在葡萄糖代谢和免疫反应中的假定调节作用。LvCHH I和LvCHH II均在眼柄的窦腺和神经节层中表达，并在感染白斑综合征病毒（WSSV）后被显著诱导。同时，在WSSV感染后12小时和24小时观察到对虾血淋巴葡萄糖水平显著升高，而血细胞内的葡萄糖在6小时时下降，然后在12小时时升高。随后通过注射重组蛋白（rLvCHH I和rLvCHH II）在体内进行rLvCHHs的功能获得实验。在对虾注射rLvCHH I后0.5小时至3小时，血淋巴葡萄糖显著增加，而在注射rLvCHH II后0.5小时下降，随后在3小时升高。与此同时，在注射rLvCHH I后3小时和6小时观察到血细胞中活性氧水平显著降低，而在rLvCHH II注射组中保持不变。rLvCHH I和rLvCHH II在体外可与原代对虾血细胞的细胞膜结合，当血细胞与rLvCHH I孵育3小时时，超氧化物歧化酶和LvRelish的表达增加。同时，抗菌肽crustin和penaeidin-4的表达也受到rLvCHH I和rLvCHH II的诱导。这些结果表明，除了葡萄糖代谢外，宿主免疫反应也可被LvCHH家族直接调节，本研究为代谢激素在无脊椎动物中的免疫调节作用提供了新的见解。
