Chu Derrick M, Antony Kathleen M, Ma Jun, Prince Amanda L, Showalter Lori, Moller Michelle, Aagaard Kjersti M
Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA.
Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, USA.
Genome Med. 2016 Aug 9;8(1):77. doi: 10.1186/s13073-016-0330-z.
Emerging evidence suggests that the in utero environment is not sterile as once presumed. Work in the mouse demonstrated transmission of commensal bacteria from mother to fetus during gestation, though it is unclear what modulates this process. We have previously shown in the nonhuman primate that, independent of obesity, a maternal high-fat diet during gestation and lactation persistently shapes the juvenile gut microbiome. We therefore sought to interrogate in a population-based human longitudinal cohort whether a maternal high-fat diet similarly alters the neonatal and infant gut microbiome in early life.
A representative cohort was prospectively enrolled either in the early third trimester or intrapartum (n = 163), with a subset consented to longitudinal sampling through the postpartum interval (n = 81). Multiple body site samples, including stool and meconium, were collected from neonates at delivery and by 6 weeks of age. A rapid dietary questionnaire was administered to estimate intake of fat, added sugars, and fiber over the past month (National Health and Examination Survey). DNA was extracted from each infant meconium/stool sample (MoBio) and subjected to 16S rRNA gene sequencing and analysis.
On average, the maternal dietary intake of fat ranged from 14.0 to 55.2 %, with an average intake of 33.1 % (σ = 6.1 %). Mothers whose diets significantly differed from the mean (±1 standard deviation) were separated into two distinct groups, a control group (n = 13, μ = 24.4 %) and a high-fat group (n = 13, μ = 43.1 %). Principal coordinate analysis revealed that the microbiome of the neonatal stool at birth (meconium) clustered differently by virtue of maternal gestational diet (PERMANOVA p = 0.001). LEfSe feature selection identified several taxa that discriminated the groups, with a notable relative depletion of Bacteroides in the neonates exposed to a maternal high-fat gestational diet (Student's t-test, p < 0.05) that persisted to 6 weeks of age.
Similar to the primate, independent of maternal body mass index, a maternal high-fat diet is associated with distinct changes in the neonatal gut microbiome at birth which persist through 4-6 weeks of age. Our findings underscore the importance of counseling pregnant mothers on macronutrient consumption during pregnancy and lactation.
新出现的证据表明，子宫内环境并非如曾经所认为的那样无菌。小鼠研究表明，孕期共生细菌可从母体传播至胎儿，不过尚不清楚是什么调节了这一过程。我们之前在非人类灵长类动物中发现，与肥胖无关，孕期和哺乳期母体高脂饮食会持续影响幼崽的肠道微生物群。因此，我们试图在一个基于人群的人类纵向队列中探究，母体高脂饮食是否同样会在生命早期改变新生儿和婴儿的肠道微生物群。
前瞻性招募了一个具有代表性的队列，入组时间为孕晚期早期或分娩时（n = 163），其中一部分人同意在产后进行纵向采样（n = 81）。在分娩时及出生后6周收集新生儿多个身体部位的样本，包括粪便和胎粪。通过一份快速饮食问卷来估计过去一个月的脂肪、添加糖和纤维摄入量（国家健康和检查调查）。从每个婴儿的胎粪/粪便样本中提取DNA（MoBio），并进行16S rRNA基因测序和分析。
平均而言，母体饮食中的脂肪摄入量在14.0%至55.2%之间，平均摄入量为33.1%（σ = 6.1%）。饮食与平均值有显著差异（±1个标准差）的母亲被分为两个不同的组，一个对照组（n = 13，μ = 24.4%）和一个高脂组（n = 13，μ = 43.1%）。主坐标分析显示，出生时新生儿粪便（胎粪）的微生物群因母体孕期饮食不同而聚类不同（PERMANOVA p = 0.001）。线性判别分析效应大小（LEfSe）特征选择确定了几个区分组别的分类群，在暴露于母体高脂孕期饮食的新生儿中，拟杆菌相对明显减少（学生t检验，p < 0.05），这种情况一直持续到6周龄。
与灵长类动物相似，与母体体重指数无关，母体高脂饮食与出生时新生儿肠道微生物群的明显变化有关，这种变化会持续到4 - 6周龄。我们的研究结果强调了在孕期和哺乳期为孕妇提供关于常量营养素摄入咨询的重要性。
