Zhang Ruofan, Huang Guowen, Ren Yuting, Wang Haifeng, Ye Yanxin, Guo Jiaqing, Wang Mengting, Zhu Weiyun, Yu Kaifan
Laboratory of Gastrointestinal Microbiology, Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China.
National Center for International Research on Animal Gut Nutrition, Nanjing Agricultural University, Nanjing, China.
Front Nutr. 2022 May 16;9:896815. doi: 10.3389/fnut.2022.896815. eCollection 2022.
As a microbial tryptophan metabolite, indole-3-carboxaldehyde (ICA) has been suggested to confer benefits to host, such as regulation of intestinal barrier function. This study aimed to elucidate the role of ICA in modulating intestinal homeostasis via using a weaned pig model. Twenty-four weaned piglets were randomly allocated into three groups: the control group (a basal diet), ICA100 group (the basal diet supplemented with 100 mg/kg ICA), and ICA200 group (the basal diet supplemented with 200 mg/kg ICA). The experiment lasted 14 d, and pigs from the control and ICA100 groups were slaughtered. The results showed no significant differences in the average daily gain (ADG) and average daily feed intake (ADFI) among the three groups ( > 0.05). However, the ICA100 group had a lower feed to gain ratio (F:G) ( < 0.05). Dietary ICA supplementation did not alter the villus height, crypt depth, and villus height/crypt depth ratio in the small intestine, and did not change the intestinal permeability and antioxidant parameters ( > 0.05). Intriguingly, ICA treatment significantly increased the jejunal, ileal and colonic indexes in piglets ( < 0.05). Besides, the expression of proliferating cell nuclear antigen (PCNA) in the intestine was up-regulated by ICA treatment. Moreover, experiments demonstrated that 15 μM ICA significantly accelerated the proliferation activity of IPEC-J2 cells, and increased the expression of the ICA receptor aryl hydrocarbon receptor (AHR) and the proliferation markers PCNA and Cyclin D1 ( < 0.05). In addition, dietary ICA supplementation modulated the intestinal flora, increasing the richness estimators and diversity index, decreasing the abundances of phylum and genera , and , and enriching the abundance of genera . These data reveal a beneficial role for the microbial metabolite ICA on intestinal epithelial proliferation, rather than intestinal barrier function, in weaned piglets.
作为一种微生物色氨酸代谢产物，吲哚 - 3 - 甲醛（ICA）已被认为对宿主有益，比如调节肠道屏障功能。本研究旨在通过使用断奶仔猪模型阐明ICA在调节肠道稳态中的作用。将24头断奶仔猪随机分为三组：对照组（基础日粮）、ICA100组（基础日粮添加100 mg/kg ICA）和ICA200组（基础日粮添加200 mg/kg ICA）。实验持续14天，对照组和ICA100组的猪被屠宰。结果显示，三组之间的平均日增重（ADG）和平均日采食量（ADFI）无显著差异（P>0.05）。然而，ICA100组的料重比（F:G）较低（P<0.05）。日粮中添加ICA并未改变小肠绒毛高度、隐窝深度以及绒毛高度/隐窝深度比值，也未改变肠道通透性和抗氧化参数（P>0.05）。有趣的是，ICA处理显著增加了仔猪空肠、回肠和结肠指数（P<0.05）。此外，ICA处理上调了肠道中增殖细胞核抗原（PCNA）的表达。而且，实验表明15 μM ICA显著加速了IPEC - J2细胞的增殖活性，并增加了ICA受体芳烃受体（AHR）以及增殖标志物PCNA和细胞周期蛋白D1的表达（P<0.05）。另外，日粮中添加ICA调节了肠道菌群，增加了丰富度估计值和多样性指数，降低了门 和属 、 的丰度，并增加了属 的丰度。这些数据揭示了微生物代谢产物ICA对断奶仔猪肠道上皮增殖而非肠道屏障功能具有有益作用。
