Electroacupuncture Improves IBS Visceral Hypersensitivity by Inhibiting the Activation of Astrocytes in the Medial Thalamus and Anterior Cingulate Cortex

Min Zhao,Yuhu Xin,Jimeng Zhao,Zhaoqin Wang,Zhe Ma,Guona Li,Zhijun Weng,Huangan Wu,Fang Zhang,Huirong Liu

doi:10.1155/2020/2562979

Abstract

Objective To explore whether the effect of electroacupuncture (EA) on visceral hypersensitivity (VH) in rats with irritable bowel syndrome (IBS) is related to the changes of astrocyte activation in the medial thalamus (MT) and anterior cingulate cortex (ACC). Method Male Sprague-Dawley rats were randomly divided into the normal control (NC) group, model control (MC) group, electroacupuncture (EA) group, and fluorocitrate (FCA) group. A model of visceral hypersensitivity was established by neonatal colorectal irritation. In the EA group, needles were inserted into the skin at the Tianshu (ST25) and Shangjuxu (ST37) acupoints, once a day for 7 days. The FCA group received intrathecal injection of FCA on the 1st, 4th, and 7th days. Visceral hypersensitivity was evaluated by the abdominal withdrawal reflex (AWR), and glial fibrillary acidic protein (GFAP) mRNA and protein levels in the MT and ACC were detected by real-time PCR, immunohistochemistry, and western blots. Results The AWR score in the MC group was significantly higher than in the NC group, and EA and FCA reduced the AWR score of VH rats. GFAP mRNA and protein levels in the MT and ACC of rats in the MC group were significantly increased compared with the NC group. After either electroacupuncture or fluorocitrate, GFAP mRNA and protein levels in the MT and ACC were both clearly reduced. Conclusion Electroacupuncture alleviates IBS visceral hypersensitivity by inhibiting the activation of astrocytes in the MT and ACC.

Highlights

Irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disease characterized by abdominal pain, abdominal distension, and other changes in defecation habits without structural alteration. e global prevalence of IBS is 10%, which seriously affects the quality of life [1, 2]
Astrocytes was found to be involved in pain signal transduction of IBS in brain regions, visceral hypersensitivity activates astrocytes in the thalamus and anterior cingulate cortex (ACC), and the activation of astrocytes is positively correlated with the behavior results of rats with visceral pain [9, 10]. erefore, it is believed that medial thalamus (MT) and ACC mediated by astrocytes are important brain regions involved in IBS visceral hypersensitivity
Under a pressure stimulation of 20 mmHg, 40 mmHg, 60 mmHg, and 80 mmHg, the abdominal withdrawal reflex (AWR) score of the model control (MC) group was significantly higher than the normal control (NC) group (P all < 0.05) (Figures 3(a)–3(d)) and the AWR scores were increased with increasing stimulation in the MC group

Summary

Introduction

Irritable bowel syndrome (IBS) is a common chronic functional gastrointestinal disease characterized by abdominal pain, abdominal distension, and other changes in defecation habits without structural alteration. e global prevalence of IBS is 10%, which seriously affects the quality of life [1, 2]. In recent years, increasing research has found that the activation of the thalamus and ACC is related to visceral hypersensitivity of IBS (Figure 1) [6, 7]. IBS could affect the activation of MT and ACC brain regions and induce the corresponding synaptic signal transmission [8]. Astrocytes was found to be involved in pain signal transduction of IBS in brain regions, visceral hypersensitivity activates astrocytes in the thalamus and ACC, and the activation of astrocytes is positively correlated with the behavior results of rats with visceral pain [9, 10]. Erefore, it is believed that MT and ACC mediated by astrocytes are important brain regions involved in IBS visceral hypersensitivity Astrocytes was found to be involved in pain signal transduction of IBS in brain regions, visceral hypersensitivity activates astrocytes in the thalamus and ACC, and the activation of astrocytes is positively correlated with the behavior results of rats with visceral pain [9, 10]. erefore, it is believed that MT and ACC mediated by astrocytes are important brain regions involved in IBS visceral hypersensitivity

Methods

Results

Conclusion