低出生体重儿肠道菌群及肠道屏障功能的研究

目的研究低出生体重儿的肠道菌群分布情况和肠道屏障功能的变化。方法以低出生体重儿(1 500g≤体重2 500g)为研究对象,采用16SrRNA荧光定量PCR技术和JY-DLT肠道屏障功能分析系统检测低出生体重儿出生后第7天粪便中双歧杆菌、乳杆菌、大肠埃希菌、肠球菌4种细菌的含量以及血清中的二胺氧化酶、D-乳酸和细菌内毒素的浓度,比较正常新生儿与低出生体重儿肠道菌群和肠道屏障功能的差异,分析不同喂养方式、并发症对低出生体重儿肠道菌群及肠道屏障功能的影响。结果 (1)低出生体重儿组粪便中大肠埃希菌、肠球菌、乳杆菌、双歧杆菌含量均明显低于健康新生儿组(P0.05),血清中二胺氧化酶、D-乳酸高于健康新生儿组(P0.05),细菌内毒素水平差异无统计学意义(P0.05)。(2)母乳喂养组低出生体重儿粪便中双歧杆菌和乳杆菌含量明显高于乳制品喂养组(P0.05),且血清中二胺氧化酶和和D-乳酸含量低于乳制品喂养组(P0.05),细菌内毒素水平差异无统计学意义(P0.05)。(3)无并发症组低出生体重儿粪便中乳杆菌和双歧杆菌含量明显高于有并发症组(P0.05),其血清中二胺氧化酶、D-乳酸和细菌内毒素水平均低于有并发症的低出生体重儿(P0.05)。结论低出生体重儿的肠道菌群和肠道屏障功能都与正常新生儿存在差异,母乳喂养有助于肠道有益菌的定植和肠道屏障功能的恢复。

The variation of intestinal microflora and intestinal barrier function in low birth weight infants

Abstract: Objective To explore intestinal microflora distribution and intestinal barrier function in low birth weight (LBW) infants. Methods Samples of feces and blood were collected from LBW infants at Day 7 after birth and normal controls. 16S rRNA fluorescent quantitative PCR was applied in determining the contents of Bifidobacteria, Lactobacilli, Escherichia coli and Enterococci in feces, and the levels of serum DAO, D-lactate and endotoxin were determined by using JY-DLT intestinal barrier function analysis system. Results (1) Compared with the healthy newborns, the contents of Bifidobacteria, Lactobacilli, Escherichia coli and Enterococci in feces in LBW group were obviously lower (P<0.05), and the serum levels of DAO and D-lactate were significantly higher (P<0.05), while the serum level of endotoxin showed no statistical difference (P>0.05). (2) Breast-fed LBW infants had higher contents of Bifidobacteria and Lactobacilli in feces (P<0.05) and lower serum levels of DAO and D-lactate (P<0.05) than dairy-fed ones, while there was no statistical difference between the two groups in the serum level of endotoxin (P>0.05). (3) Compared with the LBW infants with complications, those without complications had higher contents of Bifidobacteria and Lactobacilli in feces and lower serum levels of DAO, D-lactate and endotoxin (P<0.05). Conclusion Statistically significant differences were observed in intestinal microflora and intestinal barrier function between LBW infants and healthy newborns. Breastfeeding helps the growth of intestinal probiotics and the recovery of intestinal barrier function in LBW infants.