Abstract Vibrio parahaemolyticus is a critical pathogenic bacterium for the kuruma shrimp, Marsupenaeus japonicus. Antibacterial drug application is the main method to control vibriosis in aquaculture; however, drug residues and the emergence of resistant bacteria have restricted their use. Therefore, the present study aimed to identify metabolites that are likely to play roles in the homeostasis of the intestinal microbiota, and to further explore their application in shrimp aquaculture. Metabolomic analysis, using high-performance liquid chromatography tandem mass spectrometry (HPLC/MS) of shrimp intestinal contents, was performed. The results showed that metabolic profiles changed distinctly in shrimp intestines after V. parahaemolyticus challenge compared with that in the control. The levels of 39 metabolites changed significantly after Vibrio challenge. Notably, vitamin D3 metabolism was enhanced in shrimp intestines after Vibrio challenge. Oral administration of 0.1 mg/kg vitamin D3 effectively improved the survival rate of shrimp infected with V. parahaemolyticus. Further studies indicated that vitamin D3 promoted bacterial clearance by regulating the expression of antimicrobial peptides genes in the shrimp intestines. Transcriptomics analysis revealed that vitamin D3 functioned in shrimp intestinal immunity by activating the prophenoloxidase system and Toll signaling pathway to induce the expression of certain antimicrobial peptides to maintain microbial homeostasis. Collectively, we identified vitamin D3 as an immunomodulatory factor that plays an important role in boosting the immune response against pathogenic bacteria in shrimp.

中文翻译：

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从肠道内容物的代谢组学分析中鉴定的维生素 D3 促进虾肠道免疫的抗菌反应

摘要 副溶血性弧菌是马苏对虾Marsupenaeus japonicus的重要病原菌。应用抗菌药物是水产养殖中控制弧菌病的主要方法；然而，药物残留和耐药菌的出现限制了它们的使用。因此，本研究旨在鉴定可能在肠道微生物群稳态中发挥作用的代谢物，并进一步探索它们在对虾养殖中的应用。使用高效液相色谱串联质谱 (HPLC/MS) 对虾肠内容物进行代谢组学分析。结果表明，与对照相比，副溶血性弧菌攻击后虾肠中的代谢谱发生了明显变化。弧菌攻击后 39 种代谢物的水平发生了显着变化。值得注意的是，弧菌攻击后虾肠中的维生素 D3 代谢增强。口服0.1mg/kg维生素D3可有效提高副溶血性弧菌感染虾的存活率。进一步的研究表明，维生素 D3 通过调节虾肠中抗菌肽基因的表达来促进细菌清除。转录组学分析表明，维生素 D3 通过激活酚氧化酶原系统和 Toll 信号通路来诱导某些抗菌肽的表达以维持微生物稳态，从而在虾肠道免疫中发挥作用。总的来说，