Department of Animal Science, Laboratory of Nutritional Physiology and Feeding, School of Animal Biosciences, Agricultural University of Athens, Athens, Greece.
Department of Biotechnology, Laboratory of Molecular Biology, School of Food, Biotechnology and Development, Agricultural University of Athens, Athens, Greece.
PLoS One. 2020 May 14;15(5):e0233192. doi: 10.1371/journal.pone.0233192. eCollection 2020.
Rumen protected amino acids inclusion in ewes' diets has been proposed to enhance their innate immunity. The objective of this work was to determine the impact of dietary supplementation with rumen-protected methionine or lysine, as well as with a combination of these amino acids in two different ratios, on the expression of selected key-genes (NLRs, MyD88, TRIF, MAPK-1, IRF-3, JunD, TRAF-3, IRF-5, IL-1α, IL-10, IKK-α, STAT-3 and HO-1). Thus, sixty Chios dairy ewes (Ovis aries) were assigned to one of the following five dietary treatments (12 animals/ treatment): A: basal diet consist of concentrates, wheat straw and alfalfa hay (control group); B: basal diet +6.0 g/head rumen-protected methionine; C: basal diet + 5.0 g/head rumen-protected lysine; D: basal diet +6.0 g/head rumen-protected methionine + 5.0 g/head rumen-protected lysine and E: basal diet +12.0 g/head rumen-protected methionine + 5.0 g/head rumen-protected lysine. The results revealed a significant downregulation of relative transcript level of the IL-1α gene in the neutrophils of C and in monocytes of D ewes compared with the control. Significantly lower mRNA transcript accumulation was also observed for the MyD88 gene in the neutrophils of ewes fed with lysine only (C). The mRNA relative expression levels of JunD gene were highly induced in the monocytes, while those of IL-10 and HO-1 genes were declined in the neutrophils of ewes fed with the C and D diets compared with the control. Lower transcript levels of STAT-3 gene were observed in the neutrophils of ewes fed with either C or with E diets in comparison with the control. In conclusion, our results suggest that the dietary supplementation of ewes with rumen-protected amino acids, down regulate the expression of some genes involved in the pro-inflammatory signalling.
反刍动物保护氨基酸在母羊日粮中的添加被提议用于增强其先天免疫。本工作的目的是确定日粮中添加反刍保护蛋氨酸或赖氨酸，以及以两种不同比例组合添加这些氨基酸对选定关键基因（NLRs、MyD88、TRIF、MAPK-1、IRF-3、JunD、TRAF-3、IRF-5、IL-1α、IL-10、IKK-α、STAT-3 和 HO-1）表达的影响。因此，将 60 只基希奥（Chios）奶绵羊（Ovis aries）分配到以下五种日粮处理之一（12 只动物/处理）：A：基础日粮由精料、小麦秸秆和紫花苜蓿干草组成（对照组）；B：基础日粮+6.0 克/头反刍保护蛋氨酸；C：基础日粮+5.0 克/头反刍保护赖氨酸；D：基础日粮+6.0 克/头反刍保护蛋氨酸+5.0 克/头反刍保护赖氨酸；E：基础日粮+12.0 克/头反刍保护蛋氨酸+5.0 克/头反刍保护赖氨酸。结果表明，与对照组相比，C 组绵羊的中性粒细胞和 D 组绵羊的单核细胞中 IL-1α 基因的相对转录水平显著下调。仅用赖氨酸喂养的绵羊的中性粒细胞中 MyD88 基因的 mRNA 转录积累也明显降低（C）。在单核细胞中 JunD 基因的 mRNA 相对表达水平高度诱导，而在 C 和 D 日粮喂养的绵羊的中性粒细胞中 IL-10 和 HO-1 基因的 mRNA 相对表达水平下降与对照组相比。与对照组相比，在 C 或 E 日粮喂养的绵羊的中性粒细胞中，STAT-3 基因的转录水平较低。总之，我们的结果表明，日粮中添加反刍保护氨基酸可下调参与促炎信号的一些基因的表达。
