Effects of Dietary Tryptophan Levels on Organ Index and Small Intestine Related Gene Expression in Weaning Pigs (Sus scrofa)
MA Wen-Feng1,2,*, GUO Liang3, WANG Zhan-Bin1, ZHAO Fu-Rong1
1 College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China; 2 College of Animal Science and Technology, China Agricultural University, Beijing 100193, China; 3 College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, Tianjin 300384, China
Abstract:Tryptophan is the second or third limiting amino acid for weaning pigs (Sus scrofa), which plays an important role in the regulation of feeding intake, growth, immunity and intestinal development. The 4 different ratio of tryptophan to lysine was conducted to investigate the effects of dietary tryptophan level on serum biochemical index, organ IDO and intestinal tight junction protein gene expression in weaning pigs. A total of 240 weaning pigs (Large White×Landrace×Duroc) with an initial body weight of (6.5±0.2) kg were randomly divided into 4 treatments with 6 repetitions and 10 pigs each repetition and the experiment lasted for 28 d. The dietary ratios of tryptophan to lysine were 0.15, 0.18, 0.21, and 0.24. The result showed that compared with the group with tryptophan to lysine ratio of 0.15, when the ratio was increased to 0.18, 0.21 or 0.24, the expression of IDO gene in the spleen, kidney, stomach and ileum of weaning pigs was significantly reduced (P<0.05), and the expression of jejunum IDO mRNA in the 0.24 group was significantly increased (P<0.05). When the dietary ratios of tryptophan to lysine increased from 0.15 to 0.24, the expression of occludin and ZO-1 in the duodenum and ileum were significantly reduced (P<0.05), the jejunum expression levels of ZO-1 mRNA in the 0.18 and 0.24 groups were significantly decreased (P<0.05), while the jejunum occludin mRNA expression levels in the 0.21 group were significantly increased (P<0.05). When the ratio of dietary tryptophan to lysine increased from 0.15 to 0.24, the level of serum urea nitrogen was influenced in weaning pigs (P<0.05). It was found that when the ratio of tryptophan to lysine was adjusted from 0.15 to 0.24, the gene expression of IDO and small intestinal tight junction protein in the organism could be significantly regulated, and nitrogen metabolism of the organism could be also affected in this study. In conclusion, the optimal ratio of tryptophan to lysine for weaning pigs was 0.18. The results provides a theoretical basis for the application of tryptophan in the diet of weaning pigs.
马文锋, 郭亮, 王占彬, 赵芙蓉. 饲粮色氨酸水平对断奶仔猪器官指数及小肠相关基因表达的影响[J]. 农业生物技术学报, 2021, 29(8): 1538-1545.
MA Wen-Feng, GUO Liang, WANG Zhan-Bin, ZHAO Fu-Rong. Effects of Dietary Tryptophan Levels on Organ Index and Small Intestine Related Gene Expression in Weaning Pigs (Sus scrofa). 农业生物技术学报, 2021, 29(8): 1538-1545.
[1] 石宝石. 2016. 色氨酸促进肠道β-防御素分泌的信号通路研究[D]. 硕士学位论文, 西南大学, 导师: 唐志如, pp. 19-20. (Shi B S.2016. Study for the signal pathway of tryptophan promoting β-defensine secretion in intestine[D]. Thesis for M.S., Southwest University, Supervisor: Tang Z R, pp. 19-20) [2] 江敏. 2015. 色氨酸对肠道抗氧化能力和氨基酸转运载体的影响[D]. 硕士学位论文, 南昌大学, 导师: 阮征, pp. 40-41. (Jiang M.2015. The influence of tryptophan to antioxidant capacity and amino acid transporter[D]. Thesis for M.S., Nanchang University, Supervisor: Ruan Z, pp. 40-41) [3] 刘化伟, 石宝明, 娄蕾, 等. 2012. 饲粮中添加色氨酸对仔猪混群后行为及相关激素的影响[J]. 中国农业科学, 45(12): 2455-2461. (Liu H W, Shi B M, Lou L, et al.2012. Effects of supplement of tryptophan on behavior and related hormones in piglets after mixing[J]. Scientia Agricultura Sinica, 45(12): 2455-2461) [4] 苏有健, 李德发, 邢建军, 等. 2005. 在低蛋白日粮中添加色氨酸对仔猪生产性能及血清游离氨基酸和尿素氮的影响[J]. 中国畜牧杂志, 41(1): 26-28. (Su Y J, Li D F, Xing J J, et al.2005. Effects of tryptophan supplementation in low protein diet on performance, serum free amino acids and urea nitrogen in piglets[J]. Chinese Journal of Animal science, 41(1): 26-28.) [5] 朱艳芝, 马文锋, 陈晓晨, 等. 2020. 色氨酸分解代谢及其在猪饲粮中的应用进展[J]. 动物营养学报, 32(3): 1019-1024. (Zhu Y Z, Ma W F, Chen X C, et al.Tryptophan catabolism and its application in pig diets[J]. Chinese Journal of Animal Nutrition, 32(3):1019-1024.) [6] 宗秋芳, 钦伟云, 霍永久, 等. 2018. 猪肠上皮紧密连接蛋白研究进展[J]. 浙江农业学报, 30(8): 1435-1444. (Zong Q F, Qin W Y, Huo Y J, et al.2018. Research progress of intestinal epithelial tight junction proteins in piglets[J]. Acta Agriculturae Zhejiangensis, 30(8): 1435-1444.) [7] Alizadeh A.2016. The piglet as a model for studying dietary components in infant diets: Effects of galacto-oligosaccharides on intestinal functions[J]. British Journal of Nutrition, 115(4): 1-14. [8] Buddington R K, Elnif J, Puchalgardiner A A, et al.2001. Intestinal apical amino acid absorption during development of the pig[J]. American Journal of Physiology Regulatory Integrative & Comparative Physiology, 280(1): R241. [9] Berstad A, Raa J, Valeur J.2014. Tryptophan: 'Essential' for the pathogenesis of irritable bowel syndrome[J]. Scandinavian Journal of Gastroenterology, 49(12): 1493-1498. [10] Henry Y, Seve B, Colleaux Y, et al.1992. Interactive effects of dietary levels of tryptophan and protein on voluntary feed intake and growth performance in pigs, in relation to plasma free amino acids and hypothalamic serotonin[J]. Journal of Animal Science, 70(6): 1873-1887. [11] Kennedy P J, Allen A P, O'Neill A, et al.2015. Acute tryptophan depletion reduces kynurenine levels: Implications for treatment of impaired visuospatial memory performance in irritable bowel syndrome[J]. Psychopharmacology, 232(8): 1357-1371. [12] Kim C J, Kovacs-Nolan J A, Yang C, et al.2010. L-Tryptophan exhibits therapeutic function in a porcine model of dextran sodium sulfate (DSS)-induced colitis[J]. Journal of Nutritional Biochemistry, 21(6): 468-475. [13] Koopmans S J, Ruis M, Dekker R, et al.2005. Surplus dietary tryptophan reduces plasma cortisol and noradrenaline concentrations and enhances recovery after social stress in pigs[J]. Physiology & Behavior, 85(4): 469-478. [14] Le F N, Otten W, Merlot E.2011. Tryptophan metabolism, from nutrition to potential therapeutic applications[J]. Amino Acids, 41(5): 1195-1205. [15] Le Floc'h N, Melchior D, Seve B.2008. Dietary tryptophan helps to preserve tryptophan homeostasis in pigs suffering from lung inflammation[J]. Journal of Animal Science, 86(12): 3473-3479. [16] Liu W, Mi S, Ruan Z, et al.2017. Dietary Tryptophan enhanced the expression of tight junction protein ZO-1 in intestine[J]. Journal of Food Science, 82(2): 562-567. [17] Nevado R, Forcen R, Layunta E, et al.2015. Neomycin and bacitracin reduce the intestinal permeability in mice and increase the expression of some tight-junction proteins[J]. Revista Espanola De Enfermedades Digestivas, 107(11): 672-676. [18] Norgaard J V, Pedersen T F, Soumeh E A, et al.2015. Optimum standardized ileal digestible tryptophan to lysine ratio for pigs weighing 7-14 kg[J]. Livestock Science, 175: 90-95. [19] Stokes C R.2017. The development and role of microbial-host interactions in gut mucosal immune development[J]. Journal of Animal Science & Biotechnology, 8(2): 307-316. [20] Shin T K, Yi Y J, Kim J C, et al.2017. Reducing the dietary omega-6 to omega-3 polyunsaturated fatty acid ratio attenuated inflammatory indices and sustained epithelial tight junction integrity in weaner pigs housed in a poor sanitation condition[J]. Animal Feed Science & Technology, 22(4): 312-320. [21] Tossou M C B, Liu H, Bai M, et al.2016. Effect of high dietary tryptophan on intestinal morphology and tight junction protein of weaned pig[J]. BioMed Research International, (2): 1-6. [22] Trevisi P, Melchior D, Mazzoni M, et al.2009. A tryptophan-enriched diet improves feed intake and growth performance of susceptible weanling pigs orally challenged with K88[J]. Journal of Animal Science, 87(1): 148-156. [23] Wu G Y.2009. Amino acids: Metabolism, functions, and nutrition[J]. Amino Acids, 37(1): 1-17. [24] Xiao K, Jiao L, Cao S, et al.2016. Whey protein concentrate enhances intestinal integrity and influences transforming growth factor-β1 and mitogen-activated protein kinase signalling pathways in piglets after lipopolysaccharide challenge[J]. British Journal of Nutrition, 115(6): 984-993. [25] Yeung A W, Terentis A C, King N J, et al.2015. Role of indoleamine 2, 3-dioxygenase in health and disease[J]. Clinical Science, 129(7): 601-672. [26] Zhang H, Yin J, Li D, et al.2007. Tryptophan enhances ghrelin expression and secretion associated with increased food intake and weight gain in weanling pigs[J]. Domestic Animal Endocrinology, 33(1): 47-61.