1 Department of Microbiology, Nutrition and Dietetics, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamycka 129, 165 21 Prague 6, Czech Republic.
2 Laboratory of Gnotobiology, Institute of Microbiology of the Czech Academy of Sciences, v.v.i., Doly 183, 549 22 Novy Hradek, Czech Republic.
Benef Microbes. 2017 Apr 26;8(2):281-289. doi: 10.3920/BM2016.0138. Epub 2017 Jan 24.
The mode of delivery plays a crucial role in infant gastrointestinal tract colonisation, which in the case of caesarean section is characterised by the presence of clostridia and low bifidobacterial counts. Gut colonisation can be modified by probiotics, prebiotics or synbiotics. Human milk oligosaccharides (HMOs) are infant prebiotics that show a bifidogenic effect. Moreover, genome sequencing of Bifidobacterium longum subsp. infantis within the infant microbiome revealed adaptations for milk utilisation. This study aimed to evaluate the synbiotic effect of B. longum subsp. infantis, HMOs and human milk (HM) both in vitro and in vivo (in a humanised mouse model) in the presence of faecal microbiota from infants born by caesarean section. The combination of B. longum and HMOs or HM reduced the clostridia and G-bacteria counts both in vitro and in vivo. The bifidobacterial population in vitro significantly increased and produce high concentrations of acetate and lactate. In vitro competition assays confirmed that the tested bifidobacterial strain is a potential probiotic for infants and, together with HMOs or HM, acts as a synbiotic. It is also able to inhibit potentially pathogenic bacteria. The synbiotic effects identified in vitro were not observed in vivo. However, there was a significant reduction in clostridia counts in both experimental animal groups (HMOs + B. longum and HM + B. longum), and a specific immune response via increased interleukin (IL)-10 and IL-6 production. Animal models do not perfectly mimic human conditions; however, they are essential for testing the safety of functional foods.
分娩方式对婴儿胃肠道定植起着至关重要的作用，而剖宫产的特点是存在梭菌和双歧杆菌计数低。肠道定植可以通过益生菌、益生元和合生元来改变。人乳寡糖（HMOs）是婴儿的益生元，具有双歧杆菌的作用。此外，婴儿微生物组内长双歧杆菌亚种。婴儿的基因组测序显示出对牛奶利用的适应。本研究旨在评估长双歧杆菌亚种。婴儿、HMOs 和人乳（HM）在剖宫产婴儿粪便微生物群存在下的合生元效应，无论是在体外还是在体内（在人源化小鼠模型中）。长双歧杆菌和 HMOs 或 HM 的组合在体外和体内均降低了梭菌和 G 细菌的数量。体外双歧杆菌种群显著增加，并产生高浓度的乙酸和乳酸。体外竞争试验证实，所测试的双歧杆菌菌株是婴儿的潜在益生菌，与 HMOs 或 HM 一起作为合生元，还可以抑制潜在的致病菌。在体内未观察到体外确定的合生元作用。然而，在两个实验组（HMOs+B. longum 和 HM+B. longum）中，梭菌计数均显著减少，并且通过增加白细胞介素（IL）-10 和 IL-6 的产生来产生特定的免疫反应。动物模型不能完全模拟人体状况；然而，它们对于测试功能性食品的安全性是必不可少的。
