Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China.
Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang Agriculture and Forestry University, Hangzhou, 311300, China.
Fish Shellfish Immunol. 2022 Aug;127:74-81. doi: 10.1016/j.fsi.2022.06.005. Epub 2022 Jun 11.
Coumarin is a natural compound from plants with the molecular formula CHO. Cherax quadricarinatus (red claw crayfish) is an aquaculture species exhibiting high economic efficiency and quality that is mainly distributed and cultivated in the southeast provinces in China. In order to identify an effective herbal immunopotentiator against white spot syndrome virus (WSSV) infection, this study examined the effect of coumarin as a feed additive in protecting C. quadricarinatus against WSSV infection. The expression of immune-related genes and WSSV copies were analyzed by Q-PCR. Challenge experiments were conducted to analyze the survival rate and determine the optimal concentration of coumarin. The Phenoloxidase activity (PO), Acid phosphatase (ACP) and superoxide dismutase activity (SOD) activity and lysozyme activity were also analyzed. Total hemocyte count (THC) and apoptosis rate were determined by flow cytometry. The WSSV challenge results showed that 40 mg/kg coumarin reduced the mortality of C. quadricarinatus and delayed the WSSV infection process. Further investigation showed that coumarin treatment had a positive effect on the important immunity-related parameters THC, ACP activity, SOD activity, LZM and PO activity. Coumarin up-regulated the expression of proPO, JAK, STAT, ALF, Hsp70 and down-regulated the expression of caspase at the mRNA level. After WSSV infection, the hemocyte apoptosis rate was lower in the 40 mg/kg coumarin + WSSV group compared with the WSSV only group. These data illustrate that coumarin enhances innate immunity in C. quadricarinatus and exhibits a protective effect against WSSV infection by reducing the number of WSSV copies and slowing the process of infection, which provides a potential theoretical basis for studies of coumarin as a new aquatic feed additive in crustacean aquaculture.
香豆素是一种天然化合物，来自于具有 CHO 分子式的植物。罗氏沼虾（红螯螯虾）是一种养殖品种，具有高效益和高质量，主要分布和养殖在中国东南部省份。为了鉴定一种有效的对抗白斑综合征病毒（WSSV）感染的草药免疫增强剂，本研究考察了香豆素作为饲料添加剂保护罗氏沼虾免受 WSSV 感染的效果。通过 Q-PCR 分析了免疫相关基因和 WSSV 拷贝的表达。通过挑战实验分析了生存率，并确定了香豆素的最佳浓度。还分析了酚氧化酶活性（PO）、酸性磷酸酶（ACP）和超氧化物歧化酶活性（SOD）以及溶菌酶活性。通过流式细胞术测定总血细胞计数（THC）和凋亡率。WSSV 挑战结果表明，40mg/kg 香豆素降低了罗氏沼虾的死亡率并延缓了 WSSV 感染过程。进一步的研究表明，香豆素处理对重要的免疫相关参数 THC、ACP 活性、SOD 活性、LZM 和 PO 活性有积极影响。香豆素在 mRNA 水平上调了 proPO、JAK、STAT、ALF、Hsp70 的表达，并下调了 caspase 的表达。在 WSSV 感染后，40mg/kg 香豆素+WSSV 组的血细胞凋亡率低于仅 WSSV 组。这些数据表明，香豆素增强了罗氏沼虾的先天免疫，并通过降低 WSSV 拷贝数和减缓感染过程对 WSSV 感染表现出保护作用，为香豆素作为甲壳类水产养殖新型水产饲料添加剂的研究提供了潜在的理论依据。
