Data_Sheet_1_Short-chain fatty acids in breast milk and their relationship with the infant gut microbiota.PDF

IntroductionThe short-chain fatty acids (SCFAs) contained in breast milk play a key role in infant growth, affecting metabolism and enhancing intestinal immunity by regulating inflammation. MethodsIn order to examine the associations between the microbiota and SCFA levels in breast milk, and explore the roles of SCFAs in regulating the infant gut microbiota, we enrolled 50 paired mothers and infants and collected both breast milk and infant fecal samples. Breast milk SCFA contents were determined by UPLC-MS, and whole genome shotgun sequencing was applied to determine the microbial composition of breast milk and infant feces. The SCFA levels in breast milk were grouped into tertiles as high, medium, or low, and the differences of intestinal microbiota and KEGG pathways were compared among groups. ResultsThe results demonstrated that breast milk butyric acid (C4) is significantly associated with Clostridium leptum richness in breastmilk. Additionally, the specific Bifidobacterium may have an interactive symbiosis with the main species of C4-producing bacteria in human milk. Women with a low breast milk C4 tertile are associated with a high abundance of Salmonella and Salmonella enterica in their infants' feces. KEGG pathway analysis further showed that the content of C4 in breast milk is significantly correlated with the infants' metabolic pathways of lysine and arginine biosynthesis. DiscussionThis study suggests that interactive symbiosis of the microbiota exists in breast milk. Certain breast milk microbes could be beneficial by producing C4 and further influence the abundance of certain gut microbes in infants, playing an important role in early immune and metabolic development.引言 母乳中含有的短链脂肪酸（short-chain fatty acids, SCFAs）在婴儿生长发育中发挥关键作用，可通过调控炎症反应影响代谢进程并增强肠道免疫功能。方法 为探究母乳微生物群与短链脂肪酸水平之间的关联，并阐明短链脂肪酸在调控婴儿肠道微生物群中的作用，本研究纳入50对母婴受试者，采集母乳及婴儿粪便样本。采用超高效液相色谱-质谱联用（UPLC-MS）技术检测母乳中短链脂肪酸的含量，通过全基因组鸟枪法测序（whole genome shotgun sequencing）分析母乳与婴儿粪便的微生物群落组成。将母乳中的短链脂肪酸水平按三分位法划分为高、中、低三组，比较三组间肠道微生物群及京都基因与基因组百科全书（KEGG）通路的差异。结果 研究结果显示，母乳中的丁酸（C4）与母乳中柔嫩梭菌（Clostridium leptum）的丰度显著相关。此外，特定双歧杆菌属（Bifidobacterium）菌株可能与母乳中产丁酸的主要菌群存在交互共生关系。母乳丁酸水平处于低三分位组的母亲，其婴儿粪便中沙门氏菌属（Salmonella）及肠炎沙门氏菌（Salmonella enterica）的丰度显著升高。KEGG通路分析进一步表明，母乳中丁酸的含量与婴儿的赖氨酸和精氨酸生物合成代谢通路显著相关。讨论 本研究表明，母乳微生物群之间存在交互共生关系。部分母乳微生物可通过产生丁酸发挥有益作用，并进一步调控婴儿肠道内特定微生物的丰度，在婴儿早期免疫与代谢发育过程中发挥重要作用。