Division of Gastroenterology, University of Massachusetts Medical School, Worcester, Massachusetts.
Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts.
Gastroenterology. 2014 Mar;146(3):754-764.e3. doi: 10.1053/j.gastro.2013.11.048. Epub 2013 Dec 4.
BACKGROUND & AIMS: The alimentary tract contains a diffuse endocrine system comprising enteroendocrine cells that secrete peptides or biogenic amines to regulate digestion, insulin secretion, food intake, and energy homeostasis. Lineage analysis in the stomach revealed that a significant fraction of endocrine cells in the gastric corpus did not arise from Neurogenin3 (Neurog3)-expressing cells, unlike enteroendocrine cells elsewhere in the digestive tract. We aimed to isolate enriched serotonin-secreting and enterochromaffin-like (ECL) cells from the stomach and to clarify their cellular origin.
We used Neurogenic differentiation 1 (NeuroD1) and Neurog3 lineage analysis and examined the differentiation of serotonin-producing and ECL cells in stomach tissues of NeuroD1-cre;ROSA(tdTom), tryptophan hydroxylase 1 (Tph1)-cyan fluorescent protein (CFP), c-Kit(wsh/wsh), and Neurog3Cre;ROSA(tdTom) mice by immunohistochemistry. We used fluorescence-activated cell sorting to isolate each cell type for gene expression analysis. We also performed RNA sequencing analysis of ECL cells.
Neither serotonin-secreting nor ECL cells of the corpus arose from cells expressing NeuroD1. Serotonin-secreting cells expressed a number of mast cell genes but not genes associated with endocrine differentiation; they did not develop in c-Kit(wsh/wsh) mice and were labeled with transplanted bone marrow cells. RNA sequencing analysis of ECL cells revealed high expression levels of many genes common to endocrine cells, including transcription factors, hormones, ion channels, and solute transporters but not markers of bone marrow cells.
Serotonin-expressing cells of the gastric corpus of mice appear to be bone marrow-derived mucosal mast cells. Gene expression analysis of ECL cells indicated that they are endocrine cells of epithelial origin that do not express the same transcription factors as their intestinal enteroendocrine cell counterparts.
消化道含有弥散性内分泌系统，其中包括分泌肽或生物胺的肠内分泌细胞，以调节消化、胰岛素分泌、食物摄入和能量稳态。胃中的谱系分析显示，胃体中的一部分内分泌细胞并非起源于神经生成素 3（Neurog3）表达细胞，而不同于消化道其他部位的肠内分泌细胞。我们旨在从胃中分离出富含血清素的和肠嗜铬样（ECL）细胞，并阐明其细胞起源。
我们使用神经发生分化 1（NeuroD1）和 Neurog3 谱系分析，并通过免疫组织化学检查胃组织中产生血清素和 ECL 细胞的 NeuroD1-cre；ROSA（tdTom）、色氨酸羟化酶 1（Tph1）-青色荧光蛋白（CFP）、c-Kit（wsh/wsh）和 Neurog3Cre；ROSA（tdTom）小鼠的分化情况。我们使用荧光激活细胞分选分离每种细胞类型进行基因表达分析。我们还对 ECL 细胞进行了 RNA 测序分析。
胃体的分泌血清素细胞和 ECL 细胞均不来源于表达 NeuroD1 的细胞。分泌血清素的细胞表达了许多肥大细胞基因，但不表达与内分泌分化相关的基因；它们在 c-Kit（wsh/wsh）小鼠中不能发育，并且被移植的骨髓细胞标记。ECL 细胞的 RNA 测序分析显示，许多内分泌细胞共有的基因表达水平较高，包括转录因子、激素、离子通道和溶质转运体，但不包括骨髓细胞的标志物。
小鼠胃体表达血清素的细胞似乎是骨髓来源的黏膜肥大细胞。ECL 细胞的基因表达分析表明，它们是上皮来源的内分泌细胞，与它们的肠内分泌细胞对应物不同，不表达相同的转录因子。
