The First School of Clinical Medicine of Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, China.
Department of Radiology, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310003, China.
Oxid Med Cell Longev. 2023 Jan 19;2023:4463063. doi: 10.1155/2023/4463063. eCollection 2023.
Visceral pain caused by inflammatory bowel disease (IBD) greatly diminishes the quality of life in affected patients. Yet, the mechanism of how IBD causes visceral pain is currently not fully understood. Previous studies have suggested that the central nervous system (CNS) and gut-brain axis (GBA) play an important role in IBD-inducing visceral pain. As one of the treatments for IBD, electroacupuncture (EA) has been used to treat various types of pain and gastrointestinal diseases in clinical practice. However, whether EA relieves the visceral pain of IBD through the gut-brain axis has not been confirmed. To verify the relationship between visceral pain and CNS, the following experiments were conducted. H-NMR analysis was performed on the prefrontal cortex (PFC) tissue obtained from IBD rat models to determine the link between the metabolites and their role in EA treatment against visceral pain. Western blot assay was employed for detecting the contents of glutamate transporter excitatory amino acid transporters 2 (EAAT2) and the glutamate receptor N-methyl-D-aspartate (NMDA) to verify whether EA treatment can alleviate neurotoxic symptoms induced by abnormal increases of glutamate. Study results showed that the glutamate content was significantly increased in the PFC of TNBS-induced IBD rats. This change was reversed after EA treatment. This process was associated with increased EAAT2 expression and decreased expression of NMDA receptors in the PFC. In addition, an increase in intestinal glutamic-metabolizing bacteria was observed. In conclusion, this study suggests that EA treatment can relieve visceral pain by reducing glutamine toxicity in the PFC, and serves an alternative clinical utility.
炎症性肠病（IBD）引起的内脏疼痛极大地降低了受影响患者的生活质量。然而，IBD 如何引起内脏疼痛的机制目前尚未完全了解。先前的研究表明，中枢神经系统（CNS）和肠-脑轴（GBA）在 IBD 引起的内脏疼痛中发挥重要作用。作为 IBD 的一种治疗方法，电针（EA）已在临床实践中用于治疗各种类型的疼痛和胃肠道疾病。然而，EA 是否通过肠-脑轴缓解 IBD 的内脏疼痛尚未得到证实。为了验证内脏疼痛与中枢神经系统之间的关系，进行了以下实验。对 IBD 大鼠模型的前额叶皮层（PFC）组织进行 H-NMR 分析，以确定代谢物之间的联系及其在 EA 治疗内脏疼痛中的作用。采用 Western blot 检测谷氨酸转运体兴奋性氨基酸转运体 2（EAAT2）和谷氨酸受体 N-甲基-D-天冬氨酸（NMDA）的含量，以验证 EA 治疗是否可以减轻谷氨酸异常增加引起的神经毒性症状。研究结果表明，TNBS 诱导的 IBD 大鼠 PFC 中的谷氨酸含量显著增加。EA 治疗后这种变化得到了逆转。这一过程与 PFC 中 EAAT2 表达增加和 NMDA 受体表达减少有关。此外，还观察到肠道谷氨酸代谢细菌的增加。总之，这项研究表明，EA 治疗可以通过减轻 PFC 中的谷氨酰胺毒性来缓解内脏疼痛，为临床应用提供了一种替代方案。
