分娩和喂养方式对特应性皮炎婴儿肠道菌群的影响

Effects of delivery and feeding modes on intestinal microflora in infants with atopic dermatitis

目的:探讨不同分娩及喂养方式对特应性皮炎(AD)婴儿肠道菌群的影响。方法:收集2019年7月至2020年12月在武汉市第一医院皮肤科就诊的33例1~12月龄AD婴儿,以30例健康婴儿为对照,AD患儿与健康对照根据不同的分娩方式和喂养方式分组。取婴儿粪便提取总DNA,PCR扩增细菌的16S rRNA基因V1~V9区,应用PacBio Sequel测序仪进行高通量测序,采用Wilcoxon秩和检验比较各组菌群在属、种水平上的构成差异,选择差异菌群相对丰度与嗜酸性粒细胞计数及AD皮疹严重程度(SCORAD)评分做相关性分析。结果:顺产对照组(11例)、剖宫产对照组(19例)、顺产AD组(11例)、剖宫产AD组(22例)中相对丰度较高的5个菌属分别为双歧杆菌属、拟杆菌属、韦荣球菌属、链球菌属、大肠杆菌属。配方奶粉喂养对照组(7例)、母乳喂养对照组(12例)、混合喂养对照组(11例)、配方奶粉喂养AD组(12例)、母乳喂养AD组(8例)、混合喂养AD组(13例)中相对丰度较高的5个菌属分为双歧杆菌属、拟杆菌属、梭状芽孢杆菌属、韦荣球菌属、大肠杆菌属。线性判别分析(LEfSe)显示,不同分娩方式对照组和AD组间未见显著差异性菌群;而在不同喂养方式AD组和对照组中,配方奶粉喂养AD组阿克曼菌属、嗜黏蛋白阿克曼菌分别为属水平(LDA值=4.78)和种水平(LDA值=4.91)差异性最大的菌群。配方奶粉喂养AD组婴儿肠道阿克曼菌属和嗜黏蛋白阿克曼菌相对丰度(数值相等,均为9.60%±0.72%)均高于配方奶粉喂养对照组(均为2.50%±0.83%,Z=1.66,P=0.048)、混合喂养AD组(丰度值均为0,Z=2.26,P=0.012)及母乳喂养AD组(丰度值均为0,Z=1.85,P=0.032)。AD患儿中肠道阿克曼菌属及嗜黏蛋白阿克曼菌的相对丰度与SCORAD评分均呈正相关(ρ=0.384、0.387,均P<0.05)。结论:不同分娩方式对AD及健康婴儿肠道菌群影响无显著差异,配方奶粉喂养AD患儿肠道阿克曼菌属和嗜黏蛋白阿克曼菌相对丰度升高,可能参与AD的发病。

Objective To investigate the effect of different delivery and feeding modes on intestinal microflora in infants with atopic dermatitis(AD).Methods A total of 33 infants with AD were enrolled from Department of Dermatology,Wuhan NO.1 Hospital from July 2019 to December 2020,and 30 healthy infants were selected as control group.Then,all infants were grouped according to different delivery and feeding modes:cesarean-delivery AD group(22 cases),cesarean-delivery control group(19 cases),spontaneous-delivery AD group(11 cases),and spontaneous-delivery control group(11 cases);mixed-feeding AD group(13 cases),mixed-feeding control group(11 cases),formula milk powder-feeding AD group(12 cases),formula milk powder-feeding control group(11 cases),breastfeeding AD group(8 cases),and breastfeeding control group(12 cases).The total DNA was extracted from the infant feces,PCR was performed to amplify the V1-V9 regions of bacterial 16S rRNA gene,and PacBio Sequel sequencer was used for high-throughput sequencing.Wilcoxon rank sum test was used to compare the bacterial community composition at genus and species levels,and correlations of relative abundance of differentially abundant bacterial taxa with eosinophil counts and SCORing Atopic Dermatitis(SCORAD)scores were analyzed.Results In the spontaneous-delivery control group,cesarean-delivery control group,spontaneous-delivery AD group,and cesarean-delivery AD group,the top 5 bacterial genera with high relative abundance were Bifidobacterium,Bacteroides,Veillonella,Streptococcus,and Escherichia.In the formula milk powder-feeding control group,breastfeeding control group,mixed-feeding control group,formula milk powder-feeding AD group,breastfeeding AD group,and mixed-feeding AD group,the top 5 abundant bacterial genera were Bifidobacterium,Bacteroides,Clostridium,Veillonella,and Escherichia.Linear discriminant analysis of effect size(LEfSe)showed no significant difference in the relative abundance of bacterial taxa among different delivery mode groups;among different feeding mode groups,Akkermansia and Akkermansiamuciniphila were the most differentially abundant microbes in the formula milk powder-feeding AD group at genus(LDA=4.78)and species(LDA=4.91)levels,respectively.The relative abundance of Akkermansia and Akkermansiamuciniphila(both 9.6%±0.72%)was significantly higher in the formula milk powder-feeding AD group than in the formula milk powder-feeding control group(both 2.50%±0.83%,Z=1.66,P=0.048),the mixed-feeding AD group(both 0,Z=2.26,P=0.012)and the breastfeeding AD group(both 0,Z=1.85,P=0.032).Additionally,the relative abundance of Akkermansia and Akkermansia-muciniphila was positively correlated with SCORAD scores in AD patients(ρ=0.384,0.387,respectively,both P<0.05).Conclusion Different delivery modes did not significantly affect the intestinal flora of AD or healthy infants,and the relative abundance of Akkermansia and Akkermansiamuciniphila increased in the formula milk powder-feeding infants with AD,which may be involved in the occurrence of AD.