A Transcriptome-Led Exploration of Molecular Mechanisms Regulating Somatostatin-Producing D-Cells in the Gastric Epithelium.
A Transcriptome-Led Exploration of Molecular Mechanisms Regulating Somatostatin-Producing D-Cells in the Gastric Epithelium.
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DOI：
10.1210/en.2015-1301
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发表时间：
2015-11
期刊：
影响因子：
4.8
通讯作者：
Gribble F
中科院分区：
文献类型：
--
作者：
Adriaenssens A;Lam BY;Billing L;Skeffington K;Sewing S;Reimann F;Gribble F
胃上皮包含无数的肠内分泌细胞，这些细胞调节一系列生理功能，包括餐后调节肽的分泌、胃运动和营养吸收。产生生长抑素（SST）的d细胞存在于胃的氧合区和幽门区，并提供一种滋补抑制张力，调节邻近肠内分泌细胞的活性和胃酸分泌。由于识别原代d细胞存在问题，因此调节因子对胃d细胞作用的细胞机制尚未明确，并且不确定哪些刺激直接影响d细胞。在这项研究中，我们引入了一种转基因小鼠系SST-Cre，通过与Cre报告菌株杂交，可以促进胃d细胞的鉴定和纯化，或基因编码钙指标的细胞特异性表达。从胃窦和胃体中分离d细胞群，采用RNA测序和定量RT-PCR分析。定量测定激素、激素受体、神经递质受体和营养受体的表达。与sst阴性细胞相比，Pyy、Gipr、Chrm4、Calcrl、Taar1和Casr是在d细胞中高度富集的基因。在混合胃上皮细胞培养中进行的激素分泌测定证实，SST的分泌受肠促胰岛素激素、胆囊收缩素、乙酰胆碱、血管活性肠多肽、降钙素基因相关多肽、寡肽和微量胺的调节。使用培养的d细胞进行单细胞成像实验，胆囊收缩素和寡肽引起细胞内钙的增加。我们的数据首次提供了胃d细胞的转录组学分析和功能表征，并确定了这种细胞类型直接检测刺激的调节途径。
The stomach epithelium contains a myriad of enteroendocrine cells that modulate a range of physiological functions, including postprandial secretion of regulatory peptides, gastric motility, and nutrient absorption. Somatostatin (SST)-producing D-cells are present in the oxyntic and pyloric regions of the stomach, and provide a tonic inhibitory tone that regulates activity of neighboring enteroendocrine cells and gastric acid secretion. Cellular mechanisms underlying the effects of regulatory factors on gastric D-cells are poorly defined due to problems in identifying primary D-cells, and uncertainty remains about which stimuli influence D-cells directly. In this study, we introduce a transgenic mouse line, SST-Cre, which upon crossing with Cre reporter strains, facilitates the identification and purification of gastric D-cells, or cell-specific expression of genetically encoded calcium indicators. Populations of D-cells from the gastric antrum and corpus were isolated and analyzed by RNA sequencing and quantitative RT-PCR. The expression of hormones, hormone receptors, neurotransmitter receptors, and nutrient receptors was quantified. Pyy, Gipr, Chrm4, Calcrl, Taar1, and Casr were identified as genes that are highly enriched in D-cells compared with SST-negative cells. Hormone secretion assays performed in mixed gastric epithelial cultures confirmed that SST secretion is regulated by incretin hormones, cholecystokinin, acetylcholine, vasoactive intestinal polypeptide, calcitonin gene-related polypeptide, oligopetides, and trace amines. Cholecystokinin and oligopeptides elicited increases in intracellular calcium in single-cell imaging experiments performed using cultured D-cells. Our data provide the first transcriptomic analysis and functional characterization of gastric D-cells, and identify regulatory pathways that underlie the direct detection of stimuli by this cell type.