甘草多糖对ETEC诱导断奶腹泻仔猪肠道损伤及肠道菌群的调控机制
Regulatory mechanism of glycyrrhiza polysaccharide on intestinal damage and in-testinal flora in enterotoxigenic Escherichia coli-induced weaning diarrhea piglets
曾雯玉 1肖乐 2刘峻源 1韩雯珏 1汪芹 1刘彦泠 2范誉 2肖雄 1王自力3
作者信息
- 1. 西南大学动物医学院,重庆北碚 400715
- 2. 西南大学动物医学院,重庆北碚 400715;浙江大学动物医学中心,浙江杭州 310058
- 3. 浙江大学动物医学中心,浙江杭州 310058
- 折叠
摘要
将24头21日龄断奶仔猪随机分为空白组(Con)、模型组(Mod)和甘草多糖组(GP),连续14 d给GP组灌服甘草多糖水溶液(1 mL/kg,10 g/L),其余组灌服等量无菌水,第15天给Mod组、GP组仔猪按1 mL/kg连续3 d灌服1011 CFU/mL的产肠毒素大肠杆菌(enterotoxigenic Escherichia coli,ETEC)菌液,GP组继续灌服甘草多糖水溶液.分别记录各组仔猪腹泻评分、HE法检测肠道组织病理学变化、实时荧光定量PCR检测肠道组织IL-1β、IL-6、IL-8 mRNA水平、微生物宏基因组学分析肠道菌群变化情况、Western blot检测肠道组织NF-κB/MAPK信号通路相关蛋白水平.结果显示,与Con组相比,ETEC感染后Mod组腹泻评分极显著升高(P＜0.01),肠道组织结构破坏,大量肠绒毛脱落,V/C值极显著下降(P＜0.01),炎性因子IL-1β、IL-6和IL-8 mRNA水平极显著升高(P＜0.01),变形菌门极显著上调(P＜0.01),厚壁菌门极显著下调(P＜0.01),乳酸菌属下调,梭菌属上调,肠道组织p-JNK/JNK、p-ERK/ERK、p-p38/p38、p-p65/p65和p-IκBα/IκBα比值极显著升 高(P＜0.01);与 Mod组相比,GP组仔猪腹泻评分极显著降低(P＜0.01),肠道结构较完整,仅有少量肠绒毛脱落,V/C值极显著升高(P＜0.01),炎性因子IL-6和IL-8 mRNA水平显著或极显著降低(P＜0.05或P＜0.01),变形菌门极显著下调(P＜0.01),厚壁菌门极显著上调(P＜0.01),乳酸菌属上调,梭菌属下调,肠道组织 p-JNK/JNK、p-ERK/ERK、p-p38/p38、p-p65/p65 和 p-IκBα/IκBα 比值显著或极显著降低(P＜0.05或P＜0.01).微生物组学筛选出各组可能的标记物种分别为Con组的Lactobacillus、Mod组的Fusobacterium、GP组的Rothia和Eubacterium.结果表明,甘草多糖可有效缓解ETEC诱导的断奶仔猪腹泻,改善ETEC感染引起的肠道菌群紊乱,提高有益菌丰度,降低有害菌丰度,并通过抑制NF-κB/MAPK信号通路的激活,缓解ETEC诱导的肠道炎性损伤.
Abstract
The aim of this study was to investigate the regulation and mechanism of glycyrrhiza pol-ysaccharides in enterotoxigenic Escherichia coli(ETEC)-induced diarrhea in weaned piglets.Twen-ty-four piglets weaned at 21 days of age were randomly divided into the control group(Con),the model group(Mod),and the glycyrrhiza polysaccharide group(GP).The GP group was given gly-cyrrhiza polysaccharide aqueous solution(1 mL/kg,10 g/L)for 14 days,and the other groups were given the same amount of sterile water.On day 15,piglets in the Mod and GP groups were given 1011 CFU/mL of ETEC bacterial solution at 1 mL/kg for 3 consecutive days,while the GP group continued to receive an aqueous glycyrrhiza polysaccharide solution.The diarrhea score of the pig-lets in each group was recorded.The intestinal histopathological changes were detected by HE stai-ning.By real-time quantitative PCR,mRNA levels of IL-1,IL-6,and IL-8 in intestinal tissues were detected.The intestinal flora changes were analyzed by microbial metagenomics.The levels of NF-κB/MAPK signaling pathway-related proteins in intestinal tissues were measured by Western blot.The results showed that,after ETEC infection,the diarrhea score in the Mod group was sig-nificantly increased(P＜0.01)compared to the Con group.The intestinal tissue structure was de-stroyed in the Mod group.The V/C value was significantly decreased(P＜0.01),and the mRNA levels of inflammatory factors IL-1β,IL-6,and IL-8 were significantly increased(P＜0.01)in the Mod group compared with the Con group.Proteobacteria were significantly increased(P＜0.01),and firmicutes were significantly decreased(P＜0.01)in the Mod group compared to the Con group.Lactobacillus was decreased,Fusobacterium was increased,and the ratio of p-JNK/JNK,p-ERK/ERK,p-p38/p38,p-p65/p65,and p-IKBα/IKBα in intestinal tissue was significantly increased(P＜0.01)in the Mod group compared to the Con group.Compared with the Mod group,the diar-rhea score of piglets in the GP group was significantly decreased(P＜0.01).Only a small amount of intestinal villi shed in the GP group,and the intestinal structure was intact.The V/C value was significantly increased(P＜0.01),and mRNA levels of inflammatory cytokines IL-6 and IL-8 were significantly decreased(P＜0.05 or P＜0.01)in the GP group compared to the Mod group.Pro-teobacteria were significantly decreased(P＜0.01),and firmicutes were significantly increased(P＜0.01)in the GP group compared with the Mod group.Lactobacillus was increased,Fusobacte-rium was decreased,and the ratios of p-JNK/JNK,p-ERK/ERK,p-p38/p38,p-p65/p65,and p-IKBα/IκBα in intestinal tissues were significantly decreased(P＜0.05 or P＜0.01)in the GP group compared to the Mod group.The possible tagged species in each group were Lactobacillus in the Con group,Fusobacterium in the Mod group,and Rothia and Eubacterium in the GP group.In con-clusion,glycyrrhiza polysaccharides can effectively relieve ETEC-induced diarrhea in weaned pig-lets.Treatment with glycyrrhiza polysaccharides improves intestinal flora disorders caused by ETEC infection,increases the abundance of beneficial bacteria,and reduces the abundance of harm-ful bacteria.Moreover,glycyrrhiza polysaccharides inhibit the activation of the NF-κB/MAPK sig-naling pathway to alleviate intestinal inflammatory damage induced by ETEC.
关键词
产肠毒素大肠杆菌/断奶仔猪腹泻/肠道菌群/NF-κB/MAPK信号通路Key words
enterotoxigenic Escherichia coli/diarrhea in weaned piglets/gut microbiota/NF-κB/MAPK signaling pathway引用本文复制引用
出版年
2024
NETL
NSTL
万方数据