Medical Research

Neuromechanism of acupuncture regulating gastrointestinal motility

Kristen Sparrow • March 01, 2022

This article goes into detail on the mechanisms involved in acupuncture’s effect on the GI tract, which is closely related to my interest in vagal activity in conjunction with acupuncture treatment.

Yu Z. Neuromechanism of acupuncture regulating gastrointestinal motilityWorld J Gastroenterol. 2020;26(23):3182-3200. doi:10.3748/wjg.v26.i23.3182

Abstract

Acupuncture has been used in China for thousands of years and has become more widely accepted by doctors and patients around the world. A large number of clinical studies and animal experiments have confirmed that acupuncture has a benign adjustment effect on gastrointestinal (GI) movement; however, the mechanism of this effect is unclear, especially in terms of neural mechanisms, and there are still many areas that require further exploration. This article reviews the recent data on the neural mechanism of acupuncture on GI movements. We summarize the neural mechanism of acupuncture on GI movement from four aspects: acupuncture signal transmission, the sympathetic and parasympathetic nervous system, the enteric nervous system, and the central nervous system.

Keywords: Acupuncture, Gastrointestinal motility, Neuromechanism, Afferent fibers, Autonomic nervous system, Central nervous system

Core tip: Acupuncture has been applied in the treatment of gastrointestinal (GI) dysmotility diseases worldwide for decades. However, its underlying neuromechanisms in regulating GI motility have not been fully established. The neural regulation of GI function depends on its endogenous and exogenous nervous system. This review discusses the mechanisms of acupuncture on GI motility from various perspectives including the afferent signals, autonomic nervous system, as well as central nervous system based on its physical/pathological neural control.

INTRODUCTION

Acupuncture, as a complementary and alternative medical treatment, is used worldwide due to its advantages in terms of efficacy and safety. A literature analysis summarized the clinical diseases and symptoms that could be treated by acupuncture and moxibustion by collecting and analyzing published randomized controlled studies in the PubMed database. This analysis identified more than one hundred diseases and symptoms that were unanimously considered effectively treated, among which gastrointestinal (GI) diseases accounted for a quarter of the diseases[]. GI motility disorder is a common pathological feature in many clinical diseases[,], including gastroparesis, irritable bowel syndrome (IBS), functional dyspepsia, pseudo-obstruction, and chronic constipation, causing premature satiety, nausea, vomiting, abdominal pain, bloating, loss of appetite, and other clinical symptoms[]. Taking diabetic gastroparesis as an example, as many as 25%–55% of patients with type 1 diabetes have gastroparesis, with a slightly higher incidence rate in patients with type 2 diabetes, causing great suffering and poor quality of life in patients[]. GI motility disorder is becoming a serious public health problem and a significant burden to society; however, current treatment options for gut dysmotility are limited because of serious side effects[,].

In previous decades, many studies confirmed the efficacy of acupuncture for functional GI disorders and more recent medical research has made some progress in determining its mechanisms. The nervous system plays a key role in the benign regulation of GI movement in acupuncture. GI motility is the result of the combined effects of the nervous system, humoral factors, and the myoelectric activity of the GI tract itself, in which the nervous system plays a main role. Neural regulation of GI function depends on the following three levels: The local enteric nervous system (ENS) (endogenous regulation), the autonomic nervous system (ANS), and the central nervous system (CNS) (exogenous regulation). The aim of this review is to discuss the possible neuromechanisms of acupuncture in GI motility, based on its afferent signals and the neural regulation of GI motility.