Division of Gastroenterology and Nutrition, Department of Pediatrics, McMaster University, Hamilton, ON, Canada.
McMaster Integrative Neuroscience Discovery and Study Graduate Program, McMaster University, Hamilton, ON, Canada.
Physiol Rep. 2020 Nov;8(21):e14611. doi: 10.14814/phy2.14611.
Intestinal bacteria have been increasingly shown to be involved in early postnatal development. Previous work has shown that intestinal bacteria are necessary for the structural development and intrinsic function of the enteric nervous system in early postnatal life. Furthermore, colonization with a limited number of bacteria appears to be sufficient for the formation of a normal enteric nervous system. We tested the hypothesis that common bacterial components could influence the programming of developing enteric neurons.
The developmental programming of enteric neurons was studied by isolating enteric neural crest-derived cells from the fetal gut of C57Bl/6 mice at embryonic day 15.5. After the establishment of the cell line, cultured enteric neuronal precursors were exposed to increasing concentrations of a panel of bacterial components including lipopolysaccharide, flagellin, and components of peptidoglycan.
Exposure to bacterial components consistently affected proportions of enteric neuronal precursors that developed into nitrergic neurons. Furthermore, flagellin and D-gamma-Glu-mDAP were found to promote the development of serotonergic neurons. Proportions of dopaminergic neurons remained unchanged. Proliferation of neuronal precursor cells was significantly increased upon exposure to lipopolysaccharide and flagellin, while no significant changes were observed in the proportion of apoptotic neuronal precursors compared to baseline with exposure to any bacterial component.
These findings suggest that bacterial components may influence the development of enteric neurons.
肠道细菌越来越多地被证明参与了早期的产后发育。以前的工作表明,肠道细菌对于早期产后生活中肠神经系统的结构发育和内在功能是必需的。此外,定植有限数量的细菌似乎足以形成正常的肠神经系统。我们检验了这样一个假设,即常见的细菌成分可能会影响发育中肠神经元的编程。
通过从 C57Bl/6 小鼠的胚胎 15.5 天的胎肠中分离肠神经嵴衍生细胞,研究肠神经元的发育编程。在建立细胞系后,将培养的肠神经前体细胞暴露于一系列细菌成分的递增浓度中,包括脂多糖、鞭毛蛋白和肽聚糖成分。
暴露于细菌成分一致影响了发育成氮能神经元的肠神经前体细胞的比例。此外,鞭毛蛋白和 D-γ-Glu-mDAP 被发现促进了 5-羟色胺能神经元的发育。多巴胺能神经元的比例保持不变。脂多糖和鞭毛蛋白暴露显著增加了神经元前体细胞的增殖,而与任何细菌成分暴露相比,凋亡神经元前体细胞的比例没有明显变化。
这些发现表明,细菌成分可能会影响肠神经元的发育。