Wei Yuling, Li Bin, Long Zhe, Du Zongjun, Lv Zhao, Xiao Tiaoyi
Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, Hunan, 410128, China; College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China.
Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, Hunan, 410128, China.
Fish Shellfish Immunol. 2025 Nov;166:110604. doi: 10.1016/j.fsi.2025.110604. Epub 2025 Jul 28.
Grass carp, recognized as China's largest freshwater fish, has been severely impacted by grass carp reovirus (GCRV). Consequently, the development of new grass carp strains with heightened resistance to GCRV is a focal point of contemporary research. This team, utilizing a genetic network and map of grass carp anti-GCRV genes centered on innate immune molecules, established over several years, has categorized the original Xiangjiang River grass carp into groups based on differences in the innate immune molecules' constitutive expression levels, primarily in the complement system C3. Following multiple GCRV challenge experiments, a highly resistant strain, Xiangkang No. 1, was successfully bred. In this study, Xiangkang No. 1 (KX) grass carp and the progeny of common Xiangjiang original (PT) grass carp were used. qPCR analysis revealed distinct expression levels of immune molecules (C3, BF/C2, etc.) between the two types, with KX grass carp showing significantly higher expression in liver tissue. Furthermore, the levels of GSH-PX, T-SOD, and CAT in the liver tissue of KX grass carp were notably higher than in PT grass carp, indicating superior antioxidant capacity in KX grass carp. This correlation suggests a positive relationship between the expression of immune molecules in the liver and antioxidant capacity. Metabolome analysis identified 93 distinct metabolites in the liver of both grass carp types, predominantly categorized into nucleosides, nucleotides, nucleotide analogues, organic acids and derivatives, organic oxygen compounds, and lipid-related molecules. The enrichment of KEGG pathways indicated a concentration of metabolites in the metabolism of cofactors and vitamins, amino acid metabolism, and carbohydrate metabolism. Notably, L-Glutamic acid was significantly up-regulated in KX grass carp and was implicated in multiple pathways, suggesting its role as a targeted metabolite enhancing resistance in grass carp. Thus, this study hypothesizes a significant link between the basal expression of immune factors, antioxidant capacity, and L-Glutamic acid in grass carp. These findings provide insights into "immune metabolism" and support the breeding of resistant grass carp strains.
草鱼被认为是中国最大的淡水鱼，受到草鱼呼肠孤病毒（GCRV）的严重影响。因此，培育对GCRV具有更高抗性的新型草鱼品系是当代研究的重点。该团队利用多年建立的以天然免疫分子为中心的草鱼抗GCRV基因遗传网络和图谱，根据天然免疫分子组成型表达水平的差异，主要是补体系统C3的差异，将原湘江草鱼进行了分组。经过多次GCRV攻毒实验，成功培育出高抗性品系湘康1号。在本研究中，使用了湘康1号（KX）草鱼和普通湘江原种（PT）草鱼的后代。qPCR分析显示，两种类型的草鱼之间免疫分子（C3、BF/C2等）的表达水平存在差异，KX草鱼在肝脏组织中的表达明显更高。此外，KX草鱼肝脏组织中GSH-PX、T-SOD和CAT的水平明显高于PT草鱼，表明KX草鱼具有更强的抗氧化能力。这种相关性表明肝脏中免疫分子的表达与抗氧化能力之间存在正相关。代谢组学分析在两种草鱼的肝脏中鉴定出93种不同的代谢物，主要分为核苷、核苷酸、核苷酸类似物、有机酸及其衍生物、有机氧化合物和脂质相关分子。KEGG通路的富集表明代谢物集中在辅因子和维生素代谢、氨基酸代谢和碳水化合物代谢中。值得注意的是，L-谷氨酸在KX草鱼中显著上调，并涉及多个途径，表明其作为增强草鱼抗性的靶向代谢物的作用。因此，本研究推测草鱼中免疫因子的基础表达、抗氧化能力和L-谷氨酸之间存在重要联系。这些发现为“免疫代谢”提供了见解，并支持抗性草鱼品系的培育。
