Graduate School of International Agricultural Technology and Green, Institute of Green BioScience and Technology, Seoul National University, 1447 Pyeongchang-ro, Daewha, Pyeongchang 25354, Korea.
Toolgen Inc., Gasan Digital-ro, Geumcheon, Seoul 08594, Korea.
Cells. 2021 Apr 27;10(5):1028. doi: 10.3390/cells10051028.
Neuronal nitric oxide synthase (nNOS) has various roles as a neurotransmitter. However, studies to date have produced insufficient data to fully support the correlation between nNOS and bowel motility. This study aimed to investigate the correlation between nNOS expression and gastrointestinal (GI) tract motility using a stress-induced neonatal maternal separation (NMS) mouse model. In this study, we generated a genetically modified mouse with the HiBiT sequence knock-in into the gene using CRISPR/Cas9 for analyzing accurate nNOS expression. nNOS expression was measured in the stomach, small intestine, large intestine, adrenal gland, and hypothalamus tissues after establishing the NMS model. The NMS model exhibited a significant increase in nNOS expression in large intestine, adrenal gland, and hypothalamus. Moreover, a significant positive correlation was observed between whole gastrointestinal transit time and the expression level of nNOS. We reasoned that NMS induced chronic stress and consequent nNOS activation in the hypothalamic-pituitary-adrenal (HPA) axis, and led to an excessive increase in intestinal motility in the lower GI tract. These results demonstrated that HiBiT is a sensitive and valuable tool for analyzing in vivo gene activation, and nNOS could be a biomarker of the HPA axis-linked lower intestinal tract dysfunction.
神经元型一氧化氮合酶（nNOS）作为一种神经递质具有多种作用。然而，迄今为止的研究提供的数据不足以充分支持 nNOS 与肠道动力之间的相关性。本研究旨在使用应激诱导的新生期母体分离（NMS）小鼠模型研究 nNOS 表达与胃肠道（GI）道动力之间的相关性。在这项研究中，我们使用 CRISPR/Cas9 生成了一种基因敲入 HiBiT 序列到 基因的基因修饰小鼠，用于分析准确的 nNOS 表达。在建立 NMS 模型后，测量了胃、小肠、大肠、肾上腺和下丘脑组织中的 nNOS 表达。NMS 模型显示大肠、肾上腺和下丘脑的 nNOS 表达显著增加。此外，还观察到整个胃肠道转运时间与 nNOS 表达水平之间存在显著正相关。我们推断，NMS 诱导慢性应激和随后的下丘脑-垂体-肾上腺（HPA）轴中 nNOS 激活，导致下胃肠道蠕动过度增加。这些结果表明，HiBiT 是分析体内基因激活的敏感且有价值的工具，nNOS 可能是 HPA 轴相关下肠道功能障碍的生物标志物。
