生命早期母体高脂饮食对后代仔鼠肠道菌群、肠道屏障及肠道上皮HuR表达的影响

Influences of maternal high-fat diet in early life on intestinal flora, intestinal barrier and HuR expression in intestinal epithelium of offspring rats

目的 探究生命早期母体高脂饮食对后代仔鼠肠道菌群、肠道屏障及肠道上皮HuR表达的影响。方法 将怀孕仔鼠随机分为对照组和高脂饮食组,每组10只,出生仔鼠交叉喂养分为NN(对照组母鼠分娩且被对照组母鼠喂养)、NH(对照组母鼠分娩且被高脂饮食母鼠喂养)、HN(高脂饮食母鼠分娩且被对照组母鼠喂养)和HH(高脂饮食母鼠分娩且被高脂饮食母鼠喂养)四组,每组10只雄性仔鼠。称量体重后葡萄糖耐量试验(Glucose tolerance test, GTTs)检测各组大鼠血糖;HE染色检测仔鼠肠道病理变化;Western blot检测肠道屏障功能相关蛋白、肠道上皮RNA结合蛋白人类抗原R(human antigen R,HuR)、肿瘤坏死因子-α(Tumor Necrosis Factor-α,TNF-α)、白介素-12(IL-12)蛋白表达;粪便进行短链脂肪酸(Short chain fatty acids, SCFAs)测序以及16s测序。结果 与NN组相比较,NH组、HH组体重以及血糖均显著升高(P<0.05),回肠绒毛长度以及隐窝深度、闭合蛋白(Claudin-1)、密封蛋白(Occludin)、紧密连接蛋白-1(Zonula occludes protein, ZO-1)、HuR蛋白水平、乙酸盐、丙酸盐、丁酸盐的含量、Shannon、Simpson、Chao1指数均显著下降(P<0.05),TNF-α、IL-12蛋白水平显著增加(P<0.05);而HN组与NN组比较以上指标差异不显著;肠道菌群分析显示,所有样品均含有3个优势菌门即厚壁菌门、变形菌门、拟杆菌门,与NN组相比较,NH组厚壁菌门、乳酸杆菌属、布鲁菌属的相对丰度、厚壁菌门与拟杆菌门的比值(F/B)显著降低(P<0.05),拟杆菌门、变形菌门、大肠杆菌志贺菌属相对丰度显著增加(P<0.05);HH组较NN组厚壁菌门、乳酸杆菌属、布鲁菌属相对丰度、F/B显著降低(P<0.05),变形菌门、大肠杆菌志贺菌属相对丰度显著增加(P<0.05);HN组与NN组厚壁菌门、变形菌门、拟杆菌门、乳酸杆菌属、布鲁菌属、大肠杆菌志贺菌属的相对丰度均无显著变化(P>0.05)。结论 生命早期母体高脂饮食可使后代仔鼠有益肠道菌群降低,损伤肠道屏障,肠道上皮HuR表达下调。

Objective To investigate the influences of maternal high-fat diet in early life on intestinal flora, intestinal barrier and HuR expression in intestinal epithelium of offspring rats. Methods Pregnant rats were randomly divided into control group and high-fat diet group, with 10 rats in each group, the newborn rats were cross fed and divided into four groups: NN(delivered by the control group mother rats and fed by the control group mother rats), NH(delivered by the control group mother rats and fed by the high-fat diet mother rats), HN(delivered by the high-fat diet mother rats and fed by the control group mother rats) and HH(delivered by the high-fat diet mother rats and fed by the high-fat diet mother rats), with 10 male offspring in each group. Glucose tolerance tests(GTTs) were used to measure the blood glucose of rats in each group after weighing;HE staining was used to detect the intestinal pathological changes of the offspring rats;Western blot was applied to detect the protein expression of intestinal barrier function related proteins, intestinal epithelial RNA binding protein human antigen R(HuR), tumor necrosis factor-α(TNF-α), and interleukin-12(IL-12);feces were collected for short chain fatty acids(SCFAs) sequencing and 16s sequencing. Results Compared with NN group, the body weight and blood glucose of NH group and HH group increased obviously(P<0.05), the length of ileal villus, depth of recess, the protein levels of Claudin-1, Occludin, zonula occluden-1(ZO-1), HuR, the contents of acetate, propionate, butyrate, and the indexes of Shannon, Simpson, Chao1 decreased obviously(P<0.05), the protein levels of TNF-α and IL-12 increased obviously(P<0.05);however, there was no obvious difference between HN group and NN group;the intestinal flora analysis showed that all samples contained three dominant bacteria, namely, Firmicutes, Proteus and Bacteroides, compared with NN group, the relative abundances of Firmicutes, Lactobacillus and Brucella, the ratio of Firmicutes and Bacteroides(F/B) in NH group decreased obviously(P<0.05), the relative abundances of Bacteroides, Proteus and Escherichia coli Shigella increased obviously(P<0.05);compared with NN group, the relative abundances of Firmicutes, Lactobacillus and Brucella, and the ratio of F/B in the HH group decreased obviously(P<0.05), the relative abundances of Proteus and Escherichia coli Shigella increased obviously(P<0.05);the relative abundances of Firmicutes, Proteus, Bacteroides, Lactobacillus, Brucella and Escherichia coli Shigella in HN group and NN group had no obvious change(P>0.05). Conclusion Maternal high-fat diet in early life can reduce beneficial intestinal flora, damage intestinal barrier and down-regulate HuR expression in intestinal epithelium of offspring rats.