Acute and long-term effects of electroacupuncture alter frontal and insular cortex activity and functional connectivity during resting state

Research trends and hotspots of acupuncture therapy for obesity from 2004 to 2023: A bibliometric analysis

BACKGROUND

Acupuncture has been increasingly used in obese people, yet no bibliometric analysis of acupuncture studies for obesity exists. This bibliometric study analyzed research trends, cooperation, and knowledge dissemination on acupuncture for obesity over the past 20 years to inform future directions.

OBJECTIVES

To investigate the characteristics, hotspots, and frontiers of global scientific output in acupuncture research for obesity over the past two decades.

METHODS

We retrieved publications on acupuncture for obesity published from 2004 to 2023 from the Web of Science Core Collection. Using Citespace, VOSviewer, and Bibliometrix, we analyzed and visualized the publications, countries, institutions, authors, journals, and keywords from various angles.

RESULTS

A total of 357 articles were retrieved. The results showed that the number of annual publications on acupuncture for obesity has increased over time. China had the most publications (217 articles, 60.87 %), with Chengdu University of Traditional Chinese Medicine (24 articles, 6.72 %) as the most prolific institution. Ergene Neyhan, Huang Wei, and Zhou Zhongyu were the most productive authors (9 articles), and the article published by Cho SH in 2009 was the most cited article (60 citations). The most published journal was Evidence-based Complementary and Alternative Medicine, while the Journal of American Journal of Chinese Medicine was the most frequently cited. Recently, "electroacupuncture" "insulin resistance" and "systematic review" appeared frequently. The research hotspots and trends of acupuncture for obesity mainly focus on interventions, hotspot diseases, and mechanism exploration. According to keyword analysis, randomized controlled trials of catgut embedding and mechanistic studies of gut flora are the trends for future research.

CONCLUSION

Although China is the leading producer, multinational co-operation still needs to be strengthened. Currently, the main interventions for obesity were acupuncture and electroacupuncture, and the hot diseases were obesity combined with polycystic ovary syndrome and metabolic syndrome. In addition, randomised controlled trials of catgut embedding and mechanistic studies of gut flora may be potential directions for future research in the field of acupuncture for obesity.

Effects of electroacupuncture on obesity: A systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis evaluated the efficacy of electroacupuncture for the treatment of obesity.

METHODS

We searched 8 electronic databases for articles published between 2005 and 2021, including only randomized controlled trials (RCTs) in the review. The intervention groups received either electroacupuncture alone or electroacupuncture with standard care, whereas the control groups received sham electroacupuncture, standard care, or no treatment. The primary outcome was the body mass index (BMI), and the secondary outcomes were the body weight (BW), waist circumference (WC), hip circumference, waist-to-hip ratio (WHR), body fat mass, body fat percentage, and adverse effects. Continuous outcome data are presented as mean differences (MDs) with 95% confidence intervals (CIs).

RESULTS

This systematic review and meta-analysis included 13 RCTs involving 779 participants. Results revealed that the BMI (MD: -0.98; 95% CI: -1.35 to -0.61), BW (MD: -1.89; 95% CI: -2.97 to -0.80), WC (MD: -2.67; 95% CI: -4.52 to -0.82), and WHR (MD: -0.03; 95% CI: -0.06 to -0.01) were significantly improved in the intervention groups compared with those in the control groups. Adverse effects were reported in 5 studies. The most commonly used acupoint in the abdomen was ST25, whereas the most commonly used acupoints in other regions were ST36 and SP6 for the treatment of obesity. ST25 was the most commonly used acupoint connected by electroacupuncture.

CONCLUSION

This systematic review and meta-analysis suggested that electroacupuncture is an effective and safe therapy for simple obesity. To increase the reliability of this study, further detailed, long-term studies should be conducted on the effects of electroacupuncture on obesity.

Electro-Acupuncture Effects Measured by Functional Magnetic Resonance Imaging-A Systematic Review of Randomized Clinical Trials

INTRODUCTION

Electro-acupuncture, an innovative adaptation of traditional acupuncture, combines electrical stimulation with acupuncture needles to enhance therapeutic effects. While acupuncture is widely used, its biological mechanisms remain incompletely understood. Recent research has explored the neurophysiological aspects of acupuncture, particularly through functional magnetic resonance imaging (fMRI) to investigate its effects on brain activity.

METHODS

In this systematic review, we conducted an extensive search for randomized clinical trials examining electro-acupuncture effects measured by fMRI. We employed strict eligibility criteria, quality assessment, and data extraction.

RESULTS

Five studies met our inclusion criteria and were analyzed. The selected studies investigated electro-acupuncture in various medical conditions, including carpal tunnel syndrome, fibromyalgia, Crohn's disease, irritable bowel syndrome, and obesity. Notably, electro-acupuncture was found to modulate brain activity and connectivity in regions associated with pain perception, emotional regulation, and cognitive processing. These findings align with the holistic approach of traditional Chinese medicine, emphasizing the interconnectedness of body and mind.

DISCUSSION

In carpal tunnel syndrome, electro-acupuncture at both local and distal sites showed neurophysiological improvements, suggesting distinct neuroplasticity mechanisms. In fibromyalgia, somatosensory electro-acupuncture correlated with reduced pain severity, enhanced brain connectivity, and increased gamma-aminobutyric acid levels. For Crohn's disease, electro-acupuncture influenced the homeostatic afferent processing network, potentially mitigating gut inflammation. Electro-acupuncture for irritable bowel syndrome led to decreased activity in the anterior cingulate cortex, offering pain relief, while electro-acupuncture for obesity impacted brain regions associated with dietary inhibition and emotional regulation.

CONCLUSION

This systematic review provides evidence that electro-acupuncture can positively impact a range of medical conditions, possibly by modulating brain activity and connectivity. While the quality of the reviewed studies is generally good, further research with larger sample sizes and longer-term assessments is needed to better understand the mechanisms and optimize electro-acupuncture protocols for specific health conditions. The limited number of studies in this review emphasizes the need for broader investigations in this promising field. The research protocol was registered in PROSPERO (CRD42023465866).

Explore the effects of overweight and smoking on spontaneous brain activity: Independent and reverse

Accumulating evidence suggested that overweight and smoking often co-exist. However, current neuroimaging researches have almost always studied smoking or overweight status separately. Here we sought to investigate the neurobiological mechanisms of this comorbid association, by detecting spontaneous brain activity changes associated with smoking and weight status separately and collectively. We used 2 × 2 factorial design and included the following four groups: overweight/normal-weight smokers (n = 34/n = 30) and overweight/normal-weight non-smokers (n = 22/n = 24). The spontaneous brain activity among the four groups was comparable using an amplitude of low-frequency fluctuation (ALFF) method based on resting-state fMRI (rs-fMRI). Furthermore, correlation analyses between brain activity changes, smoking severity and BMI values were performed. A main effect of smoking was discovered in the default mode network (DMN) and visual network related brain regions. Moreover, overweight people had high ALFF value in the brain regions associated with reward and executive control. More importantly, smoking and overweight both affected brain activity of the middle temporal gyrus (MTG), but the effect was opposite. And the brain activity of MTG was negatively correlated with smoking years, pack year and BMI value. These results suggest that smoking and overweight not only affect spontaneous brain activity alone, but also paradoxically affect spontaneous brain activity in the MTG. This suggests that we need to control for weight as a variable when studying spontaneous brain activity in smokers. Besides, this interaction may provide a neurological explanation for the comorbidity of overweight and smoking and a target for the treatment of comorbid populations.

Electroacupuncture enhances resting-state functional connectivity between dorsal caudate and precuneus and decreases associated leptin levels in overweight/obese subjects

Electroacupuncture (EA) is a safe and effective method for treating obesity. However, how it modulates reward-related brain activity/functional connectivity and gut hormones remains unclear. We employed resting-state functional magnetic resonance imaging (RS-fMRI) and resting-state functional connectivity (RSFC) to investigate EA induced changes in resting-state activity and RSFC in reward-related regions and its association with gut hormones in overweight/obese subjects who received real (n = 20) and Sham (n = 15) stimulation. Results showed reduced leptin levels was positively correlated with reduced body mass index (BMI) and negatively correlated with increased cognitive-control as measured with Three-Factor-Eating-Questionnaire (TFEQ). Significant time effects on RSFC between dorsal caudate (DC) and precuneus were due to significant increased RSFC strength in both EA and Sham groups. In addition, increased RSFC of DC-precuneus was negatively correlated with reduced BMI and leptin levels in the EA group. Mediation analysis showed that the relationship between increased DC-precuneus RSFC strength and reduced BMI was mediated by reduced leptin levels. These findings reflect the association between EA-induced brain reward-related RSFC and leptin levels, and decreased leptin levels mediated altered DC-precuneus RSFC strength and consequent weight-loss, suggesting the potential role of EA in reducing weight and appetite.

Obesity Animal Models for Acupuncture and Related Therapy Research Studies

Obesity and related diseases are considered as pandemic representing a worldwide threat for health. Animal models are critical to validate the effects and understand the mechanisms related to classical or innovative preventive and therapeutic strategies. It is, therefore, important to identify the best animal models for translational research, using different evaluation criteria such as the face, construct, and predictive validity. Because the pharmacological treatments and surgical interventions currently used for treating obesity often present many undesirable side effects, relatively high relapse probabilities, acupuncture, electroacupuncture (EA), and related therapies have gained more popularity and attention. Many kinds of experimental animal models have been used for obesity research studies, but in the context of acupuncture, most of the studies were performed in rodent obesity models. Though, are these obesity rodent models really the best for acupuncture or related therapies research studies? In this study, we review different obesity animal models that have been used over the past 10 years for acupuncture and EA research studies. We present their respective advantages, disadvantages, and specific constraints. With the development of research on acupuncture and EA and the increasing interest regarding these approaches, proper animal models are critical for preclinical studies aiming at developing future clinical trials in the human. The aim of the present study is to provide researchers with information and guidance related to the preclinical models that are currently available to investigate the outcomes of acupuncture and related therapies.