Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, Sichuan 611130, China; Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, China; Key Laboratory for Animal Disease-Resistance Nutrition of China Ministry of Education, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
Fish Shellfish Immunol. 2017 Nov;70:682-700. doi: 10.1016/j.fsi.2017.09.055. Epub 2017 Sep 23.
The objective of this study was to evaluate the effects of dietary pyridoxine (PN) deficiency on growth performance, intestinal immune function and the potential regulation mechanisms in young grass carp (Ctenopharyngodon idella). Fish were fed six diets containing graded levels of PN (0.12-7.48 mg/kg) for 70 days. After that, a challenge test was conducted by infection of Aeromonas hydrophila for 14 days. The results showed that compared with the optimal PN level, PN deficiency: (1) reduced the production of innate immune components such as lysozyme (LZ), acid phosphatase (ACP), complements and antimicrobial peptides and adaptive immune components such as immunoglobulins in three intestinal segments of young grass carp (P < 0.05); (2) down-regulated the mRNA levels of anti-inflammatory cytokines such as transforming growth factor β (TGF-β), interleukin 4/13A (IL-4/13A) (rather than IL-4/13B), IL-10 and IL-11 partly relating to target of rapamycin (TOR) signalling [TOR/ribosomal protein S6 kinases 1 (S6K1) and eIF4E-binding proteins (4E-BP)] in three intestinal segments of young grass carp; (3) up-regulated the mRNA levels of pro-inflammatory cytokines such as tumour necrosis factor α (TNF-α) [not in the proximal intestine (PI) and distal intestine (DI)], IL-1β, IL-6, IL-8, IL-12p35, IL-12p40, IL-15 and IL-17D [(rather than interferon γ2 (IFN-γ2)] partly relating to nuclear factor kappa B (NF-κB) signalling [IκB kinase β (IKKβ) and IKKγ/inhibitor of κBα (IκBα)/NF-κB (p65 and c-Rel)] in three intestinal segments of young grass carp. These results suggest that PN deficiency could impair the intestinal immune function, and the potential regulation mechanisms were partly associated with TOR and NF-κB signalling pathways. In addition, based on percent weight gain (PWG), the ability against enteritis and LZ activity, the dietary PN requirements for young grass carp were estimated to be 4.43, 4.75 and 5.07 mg/kg diet, respectively.
本研究旨在评估日粮吡哆醇（PN）缺乏对草鱼幼鱼生长性能、肠道免疫功能的影响及其潜在的调控机制。试验采用 6 种含不同 PN 水平（0.12-7.48mg/kg）的饲料，对草鱼幼鱼进行 70 天的饲养。然后进行为期 14 天的嗜水气单胞菌攻毒试验。结果表明，与最适 PN 水平相比，PN 缺乏：（1）降低了草鱼三个肠道段的固有免疫成分（如溶菌酶（LZ）、酸性磷酸酶（ACP）、补体和抗菌肽）和适应性免疫成分（如免疫球蛋白）的产生（P<0.05）；（2）下调了三个肠道段抗炎细胞因子（如转化生长因子β（TGF-β）、白细胞介素 4/13A（IL-4/13A）（而非 IL-4/13B）、IL-10 和 IL-11）的 mRNA 水平，这些因子部分与雷帕霉素（TOR）信号通路（TOR/核糖体蛋白 S6 激酶 1（S6K1）和 eIF4E 结合蛋白（4E-BP））有关；（3）上调了三个肠道段促炎细胞因子（如肿瘤坏死因子-α（TNF-α）[在近端肠（PI）和远端肠（DI）中没有]、IL-1β、IL-6、IL-8、IL-12p35、IL-12p40、IL-15 和 IL-17D）（而非干扰素-γ2（IFN-γ2））的 mRNA 水平，这些因子部分与核因子-κB（NF-κB）信号通路（IκB 激酶β（IKKβ）和 IKKγ/κB 抑制蛋白α（IκBα）/NF-κB（p65 和 c-Rel））有关。这些结果表明，PN 缺乏会损害肠道免疫功能，其潜在的调控机制部分与 TOR 和 NF-κB 信号通路有关。此外，基于增重率（PWG）、抗肠炎能力和 LZ 活性，草鱼幼鱼对 PN 的需要量估计分别为 4.43、4.75 和 5.07mg/kg 饲料。
