Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal Health, Laboratory of Gastrointestinal Microbiology, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, 210095, China.
Microb Biotechnol. 2018 Jul;11(4):734-746. doi: 10.1111/1751-7915.13266. Epub 2018 Apr 6.
We previously reported that protein-restricted rats experienced compensatory growth when they were switched to a normal protein diet (NPD). This study aimed to investigate the changes in gene expression and microbiome in the jejunum of compensatory-growth rats. Weaned Sprague-Dawley rats were assigned to an N group, an LN group and an L group. The rats in the L and N groups were fed a low protein diet (LPD) and the NPD respectively. The rats in the LN group were fed with the LPD for 2 weeks, followed by the NPD. The experiment lasted 70 days, and the rats were sacrificed for sampling on days 14, 28 and 70 to determine the jejunal morphology, microbiome and gene expression related to digestive, absorptive and barrier function. The results showed that, although rats in the LN group had temporarily impaired morphology and gene expression in the jejunum on day 14 in response to the LPD, they had improved jejunal morphology and gene expression related to jejunal function on day 28 compared to rats in the N group. This improvement might promote compensatory growth of rats. However, lower expression of genes related to nutrient absorption and undifferentiated villous height (VH) were observed in the jejunum of rats in the LN group on day 70. In contrast, rats in the L group had lower VH on day 28 and day 70, while the expression of absorptive genes increased on day 28 compared to rats in the N group. Additionally, dramatic microbial changes in the jejunum of compensatory-growth rats were observed, principally for Lactobacillus, Streptococcus, Corynebacterium and Staphylococcus. Moreover, the abundance of Lactobacillus, Streptococcus, Corynebacterium and Staphylococcus significantly correlated with gene expression in the jejunum as revealed by the correlation analysis.
我们之前报道过，蛋白质限制饮食的大鼠在转换为正常蛋白质饮食（NPD）后会经历补偿性生长。本研究旨在探讨补偿性生长大鼠空肠基因表达和微生物组的变化。将断奶 Sprague-Dawley 大鼠分为 N 组、LN 组和 L 组。L 组和 N 组大鼠分别喂食低蛋白饮食（LPD）和 NPD。LN 组大鼠先喂食 LPD 2 周，再喂食 NPD。实验持续 70 天，在第 14、28 和 70 天处死大鼠取样，以确定空肠形态、微生物组和与消化、吸收和屏障功能相关的基因表达。结果表明，尽管 LN 组大鼠在 LPD 作用下第 14 天空肠形态和基因表达暂时受损，但与 N 组大鼠相比，第 28 天空肠形态和与空肠功能相关的基因表达有所改善。这种改善可能促进了大鼠的补偿性生长。然而，LN 组大鼠第 70 天空肠中与营养吸收和未分化绒毛高度（VH）相关的基因表达较低。相比之下，L 组大鼠第 28 天和第 70 天空肠 VH 较低，而第 28 天吸收基因表达增加。此外，补偿性生长大鼠空肠中微生物发生了明显变化，主要是乳杆菌属、链球菌属、棒状杆菌属和葡萄球菌属。此外，通过相关性分析发现，空肠中乳杆菌属、链球菌属、棒状杆菌属和葡萄球菌属的丰度与基因表达显著相关。
