Balta Igori, Stef Lavinia, Butucel Eugenia, Gradisteanu Pircalabioru Gratiela, Venig Adelina, Ward Patrick, Deshaies Myriam, Pet Ioan, Stef Ducu, Koyun Osman Y, Callaway Todd R, Gundogdu Ozan, Corcionivoschi Nicolae
Bacteriology Branch, Veterinary Sciences Division, Agri-Food and Biosciences Institute, Belfast BT4 3SD, UK.
Faculty of Animal Science and Biotechnologies, University of Agricultural Sciences and Veterinary Medicine, 400372 Cluj-Napoca, Romania.
Antioxidants (Basel). 2022 May 15;11(5):974. doi: 10.3390/antiox11050974.
Nematopsis messor infections severely impact on shrimp’s health with devastating economic consequences on shrimp farming. In a shrimp primary intestinal cells (SGP) model of infection, a sub-inhibitory concentration (0.5%) of natural antimicrobials (Aq) was able to reduce the ability of N. messor to infect (p < 0.0001). To prevent N. messor infection of SGP cells, Aq inhibits host actin polymerization and restores tight junction integrity (TEER) and the expression of Zo-1 and occluding. The oxidative burst, caused by N. messor infection, is attenuated by Aq through the inhibition of NADPH-produced H2O2. Simultaneous to the reduction in H2O2 released, the activity of catalase (CAT) and superoxide dismutase (SOD) were also significantly increase (p < 0.0001). The antimicrobial mixture inactivates the ERK signal transduction pathway by tyrosine dephosphorylation and reduces the expression of DCR2, ALF-A, and ALF-C antimicrobial peptides. The observed in vitro results were also translated in vivo, whereby the use of a shrimp challenge test, we show that in N. messor infected shrimp the mortality rate was 68% compared to the Aq-treated group where the mortality rate was maintained at 14%. The significant increase in CAT and SOD activity in treated and infected shrimp suggested an in vivo antioxidant role for Aq. In conclusion, our study shows that Aq can efficiently reduce N. messor colonization of shrimp’s intestinal cells in vitro and in vivo and the oxidative induced cellular damage, repairs epithelial integrity, and enhances gut immunity.
梅氏线虫感染严重影响对虾健康，给对虾养殖带来毁灭性的经济后果。在对虾原发性肠细胞（SGP）感染模型中，天然抗菌剂（Aq）的亚抑制浓度（0.5%）能够降低梅氏线虫的感染能力（p < 0.0001）。为防止梅氏线虫感染SGP细胞，Aq抑制宿主肌动蛋白聚合，恢复紧密连接完整性（TEER）以及闭合蛋白和闭合小环蛋白1的表达。梅氏线虫感染引起的氧化爆发通过Aq抑制NADPH产生的过氧化氢而减弱。在过氧化氢释放减少的同时，过氧化氢酶（CAT）和超氧化物歧化酶（SOD）的活性也显著增加（p < 0.0001）。抗菌混合物通过酪氨酸去磷酸化使ERK信号转导通路失活，并降低DCR2、ALF-A和ALF-C抗菌肽的表达。体外观察到的结果也在体内得到验证，通过对虾攻毒试验，我们发现，感染梅氏线虫的对虾死亡率为68%，而Aq处理组的死亡率维持在14%。处理组和感染组对虾中CAT和SOD活性显著增加，表明Aq在体内具有抗氧化作用。总之，我们的研究表明，Aq能够在体外和体内有效减少梅氏线虫在对虾肠道细胞中的定殖，减轻氧化诱导的细胞损伤，修复上皮完整性，并增强肠道免疫力。
