The effect of electroacupuncture at ST36 on severe thermal injury-induced remote acute lung injury in rats

Comprehensive landscape-style investigation of the molecular mechanism of acupuncture at ST36 single acupoint on different systemic diseases

The principle of acupoint stimulation efficacy is based on traditional meridian theory. However, the molecular mechanisms underlying the therapeutic effects of acupoints in treating diseases remain unclear in modern scientific understanding. In this study, we selected the ST36 acupoint for investigation and summarized all relevant literature from the PubMed database over the past 10 years. The results indicate that stimulation of ST36 single acupoints has therapeutic effects mainly in models of respiratory, neurological, digestive, endocrine and immune system diseases. And it can affect the inflammatory state, oxidative stress, respiratory mucus secretion, intestinal flora, immune cell function, neurotransmitter transmission, hormone secretion, the network of Interstitial Cells of Cajal (ICC) and glucose metabolism of the organism in these pathological states. Among them, acupuncture at the ST36 single point has the most prominent function in regulating the inflammatory state, which can mainly affect the activation of MAPK signaling pathway and drive the "molecular-cellular" mode involving macrophages, T-lymphocytes, mast cells (MCs) and neuroglial cells as the core to trigger the molecular level changes of the acupuncture point locally or in the target organ tissues, thereby establishing a multi-system, multi-target, multi-level molecular regulating mechanism. This article provides a comprehensive summary and discussion of the molecular mechanisms and effects of acupuncture at the ST36 acupoint, laying the groundwork for future in-depth research on acupuncture point theory.

The autonomic nervous system: A potential link to the efficacy of acupuncture

The autonomic nervous system (ANS) is a diffuse network that regulates physiological systems to maintain body homeostasis by integrating inputs from the internal and external environment, including the sympathetic, parasympathetic, and enteric nervous systems (ENS). Recent evidence suggests that ANS is one of the key neural pathways for acupuncture signal transduction, which has attracted worldwide attention in the acupuncture field. Here, we reviewed the basic and clinical research published in PubMed over the past 20 years on the effects of acupuncture on ANS regulation and homeostasis maintenance. It was found that acupuncture effectively alleviates ANS dysfunction-associated symptoms in its indications, such as migraine, depression, insomnia, functional dyspepsia, functional constipation. Acupuncture stimulation on some specific acupoints activates sensory nerve fibers, the spinal cord, and the brain. Using information integration and efferents from a complex network of autonomic nuclei of the brain, such as the insular cortex (IC), prefrontal cortex, anterior cingulate cortex (ACC), amygdala (AMG), hypothalamus, periaqueductal gray (PAG), nucleus tractus solitarius (NTS), ventrolateral medulla (VLM), nucleus ambiguus (AMB), acupuncture alleviates visceral dysfunction, inflammation via efferent autonomic nerves, and relieves pain and pain affect. The modulating pattern of sympathetic and parasympathetic nerves is associated with acupuncture stimulation on specific acupoints, intervention parameters, and disease models, and the relationships among them require further exploration. In conclusion, ANS is one of the therapeutic targets for acupuncture and mediates acupuncture's actions, which restores homeostasis. A systemic study is needed to determine the rules and mechanisms underlying the effects of acupoint stimulation on corresponding organs mediated by specific central nervous networks and the efferent ANS.

Electroacupuncture Preconditioning Alleviates Lipopolysaccharides-Induced Acute Lung Injury by Downregulating LC3-II/I and Beclin 1 Expression

Our study aimed to investigate the effect of electroacupuncture pretreatment on the inflammatory response and expression levels of LC3-II/I and Beclin 1 using a model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). Eighteen male Sprague-Dawley (SD) rats were randomly divided into three groups: normal control group (NC, n = 6), LSP modeling group (LM, n = 6), and electroacupuncture group (EA, n = 6). Rats in the EA group received electroacupuncture pretreatment at bilateral Zusanli (ST36) and Chize (LU5) points for five days (30 min each time daily, frequency; 3 Hz/15 Hz, intensity; 1 mA). Rats in the EA and LM groups were then injected with 5 mg/kg LPS (Beijing, Solarbio Company, concentration; 5 mg/mL) through the tail vein, while those in the NC group were injected with 5 mg/kg saline. The animals were sacrificed six hours after LPS or saline injection through cervical vertebrae by dislocation under deep anesthesia. Orbital blood was collected for the analysis of serum inflammatory factors including interleukin-1β (IL-1β) and transforming growth factor-β (TGF-β). The lower left lung was excised, stained with hematoxylin-eosin (HE), and subjected to histopathological analysis. The mRNA and protein expression of Beclin 1 and LC3 II/I in the lower right lung tissues were detected via RT-qPCR and Western blot analyses, respectively. The results showed that lung injury score was significantly higher in the LM group than that of the NC group (P < 0.01) and EA group (P < 0.01). The IL-1β contents were significantly decreased in the EA group (P < 0.01) than in the LM group. In contrast, the GF-β contents were increased in the EA group significantly when compared with the LM group (P < 0.01). RT-qPCR and Western blot detection showed that the relative gene expression of LC3-II/I and Beclin 1 was significantly lower in the EA group than in the LM group (P < 0.01). However, the relative protein expression level of LC3-II/I and Beclin 1 was slightly lower in the EA group than the in LM group (P > 0.05). These results show that electroacupuncture pretreatment reduces the inflammatory response in ALI and can protect lung tissue by inhibiting the gene and protein expression levels of LC3-II/I and Beclin 1.

The Effect of Acupuncture on Modulating Inflammatory Cytokines in Rodent Animal Models of Respiratory Disease: A Systematic Review and Meta-Analysis

Purpose

Although respiratory diseases (RD) are rapidly becoming a global health issue due to their high mortality and prevalence, there are limitations to the currently available treatments. Acupuncture has been recognized to mitigate many diseases by reducing inflammation and modulating cytokines. However, no systematic analysis has been performed to examine the effects of acupuncture on RD. We aimed to evaluate the effects of acupuncture on rodent animal models of RD.

Methods

PubMed, EMBASE, MEDLINE, and the Research Information Service System were searched to retrieve studies that met our inclusion/exclusion criteria. The quality of each included study was evaluated using a 10-item checklist modified from the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies. With adequate data extracted, meta-analysis was performed using RevMan software.

Results

A total of 18 studies were included, and the mean quality assessment was 5.7. The meta-analysis revealed that acupuncture had a significant effect on changing the cytokine levels, including pro-/anti-inflammatory, Th1-, Th2- and Th17- specific cytokines.

Conclusion

Although there were limitations in the number of included studies, the results suggest that acupuncture can be a possible treatment for RD through its modulation of various cytokines, leading to reduced inflammation.

Anti-Inflammatory Effects of Acupuncture at ST36 Point: A Literature Review in Animal Studies

So far, a number of acupuncture studies have shown anti-inflammatory effects of acupuncture treatment, mostly known at specific point ST36. However, there is no literature that oversaw the inflammation-regulatory effects of acupuncture in each tissue. Therefore, we investigated how acupuncture at specific acupoint ST36 regulates inflammation and its underlying mechanisms. We searched literatures on PubMed until July 2021 using the keywords “animal, acupuncture, ST36, inflammation, immune,” and 292 literatures were searched. We ultimately selected 69 studies to determine the anti-inflammatory actions of acupuncture at ST36 and classified the changes of inflammatory mediators according to target regions. Forty-three studies were included in body fluids, 27 studies in the digestive system, 17 studies in the nervous system, and 30 studies in other tissues or organs. In this review, we found that acupuncture at ST36 has clinical benefits in relieving inflammation through several mechanisms such as vagus nerve activation, toll-like receptor 4 (TLR4)/NF-κB signaling, macrophage polarization, mitogen-activated protein kinase (MAPK) signaling pathway, and cholinergic anti-inflammatory pathway. We expect that these data will inform further studies related to ST36 acupuncture on inflammation.

Research Progress of Electrical Stimulation in Ischemic Heart Disease

Ischemic heart disease (IHD) is a considerable health burden worldwide with high mortality and morbidity. Treatments for IHD are mainly focused on decreasing oxygen demand or increasing myocardial oxygen supply, including pharmacological, interventional, and surgical treatment, but there are also some limitations. Therefore, it is important to find a simple, effective, and economical treatment. As non-invasive and safe physiotherapy, electrical stimulation (ES) has a promising application in the treatment of IHD. Current studies suggest that ES can affect the occurrence and development of IHD by promoting angiogenesis, regulating autophagy and apoptosis, inhibiting the inflammatory response and oxidative stress. In this review, we focus predominantly on the mechanism of ES and the current progress of ES therapy in IHD, furthermore, give a brief introduction to the forms of ES in clinical application.

Effect of Transcutaneous Electrical Acupoint Stimulation on One-Lung Ventilation-Induced Lung Injury in Patients Undergoing Esophageal Cancer Operation

OBJECTIVE

To investigate the effect of transcutaneous electrical acupoint stimulation (TEAS) on one-lung ventilation-induced injury in patients undergoing esophageal cancer operation.

METHODS

The participants (n = 121) were randomly assigned into TEAS and sham groups. The TEAS group was given transcutaneous electrical stimulation therapy. The acupoints selected were Feishu (BL13), Hegu (L14), and Zusanli (ST36) and were treated 30 minutes before induction of anesthesia; treatment lasts 30 minutes. The sham group was connected to the electrode on the same acupoints, but electronic stimulation was not applied. The levels of oxygenation index (PaO2/FiO2) and alveolar-arterial oxygen tension difference (A-aDO2) before one-lung ventilation (T1), 30 minutes after one-lung ventilation (T2), 2 hours after one-lung ventilation (T3), and 1 hour after the operation (T4) and the levels of serum tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) at T1, T2, T3, and 24 hours after the operation (T5) were taken as the primary endpoints. The incidence of postoperative pulmonary complications, removal time of thoracic drainage tube, and length of hospital stay were taken as the secondary endpoints.

RESULTS

Compared with that, in the sham group, the level of PaO2/FiO2 in the TEAS group was significantly increased at T2, T3, and T4, and the level of A-aDO2 was significantly reduced at T2 and T3 (P < 0.05). Besides, compared with that, in the sham group, the level of serum TNF-α at T2, T3, and T5, as well as the level of serum IL-6 at T3 and T5, was significantly reduced, whereas the level of serum IL-10 at T3 was significantly increased (P < 0.05). The incidences of pulmonary infection and pleural effusion in the TEAS group were significantly lower than that in the sham group, and the removal time of thoracic drainage tube and the length of hospital stay in the TEAS group were significantly shorter than that in the sham group (P < 0.05).

CONCLUSIONS

TEAS could effectively increase the levels of PaO2/FiO2 and IL-10, reduce the levels of A-aDO2, TNF-α, and IL-6, and reduce the incidence of pulmonary complications. Moreover, it could also contribute to shorten the removal time of thoracic drainage tube and the length of hospital stay.

Laser Speckle Imaging of Sensitized Acupoints

Acupoints microcirculatory dynamics vary depending on the body's health status. However, the functional changes observed during acupoint sensitization, that is, the disease-induced change from a "silenced" to an "activated" status, remain elusive. In this study, the microcirculatory changes at acupoints during sensitization were characterized. Thirty SD rats were randomly divided into five groups: normal control group (N), sham osteoarthritis group (S), light osteoarthritis group (A), mild osteoarthritis group (B), and heavy osteoarthritis group (C). The obtained results showed that the blood perfusion levels at the acupoints Yanglingquan (GB34), Zusanli (ST36), and Heding (EX-LE2) in groups A, B, and C were higher than those in groups N and S on days 14, 21, and 28 (p < 0.01 or p < 0.05). A significant difference in the blood perfusion was also observed at the acupoint Weizhong (BL40) in groups B and C on days 21 and 28 (p < 0.01). In addition, remarkable differences in the level of blood perfusion at the GB34, ST36, and EX-LE2 acupoints were observed on day 28 (p < 0.01 or p < 0.05) among groups A, B, and C. No marked differences in blood perfusion levels were observed at the nonacupoint site among all groups. In conclusion, acupoint sensitization is associated with an increase in the level of local blood perfusion at specific acupoints, and this increase is positively correlated with the severity of the disease. The functional changes in microcirculation at acupoints during sensitization reflect the different physiological and pathological conditions imposed by the disease.

Electroacupuncture therapy in inflammation regulation: current perspectives

Although acupuncture therapy is increasingly used to treat diverse symptoms and disorders in humans, its underlying mechanism is not known well. Only recently have experimental studies begun to provide insights into how acupuncture stimulation generates and relates to pathophysiological responsiveness. Acupuncture intervention is frequently used to control pathologic symptoms in several visceral organs, and a growing number of studies using experimental animal models suggest that acupuncture stimulation may be involved in inducing anti-inflammatory responses. The vagus nerve, a principal parasympathetic nerve connecting neurons in the central nervous system to cardiovascular systems and a majority of visceral organs, is known to modulate neuroimmune communication and anti-inflammatory responses in target organs. Here, we review a broad range of experimental studies demonstrating anti-inflammatory effects of electroacupuncture in pathologic animal models of cardiovascular and visceral organs and also ischemic brains. Then, we provide recent progress on the role of autonomic nerve activity in anti-inflammation mediated by electroacupuncture. We also discuss a perspective on the role of sensory signals generated by acupuncture stimulation, which may induce a neural code unique to acupuncture in the central nervous system.

Nerve Stimulation: Immunomodulation and Control of Inflammation

Neuronal stimulation is an emerging field in modern medicine to control organ function and re-establish physiological homeostasis during illness. Transdermal nerve stimulation with electroacupuncture is currently endorsed by the World Health Organization (WHO) and the National Institutes of Health (NIH), and is used by millions of people to control pain and inflammation. Recent advances in electroacupuncture may permit activation of specific neuronal networks to prevent organ damage in inflammatory and infectious disorders. Experimental studies of nerve stimulation are also providing new information on the functional organization of the nervous system to control inflammation and its clinical implications in infectious and inflammatory disorders. These studies may allow the design of novel non-invasive techniques for nerve stimulation to help to control immune and organ functions.

Comprehensive evaluation of gene expression signatures in response to electroacupuncture stimulation at Zusanli (ST36) acupoint by transcriptomic analysis

Background

Electroacupuncture (EA) has been applied to treat and prevent diseases for years. However, molecular events happened in both the acupunctured site and the internal organs after EA stimulation have not been clarified.

Methods

Here we applied transcriptomic analysis to explore the gene expression signatures after EA stimulation. Mice were applied EA stimulation at ST36 for 15 min and nine tissues were collected three hours later for microarray analysis.

Results

We found that EA affected the expression of genes not only in the acupunctured site but also in the internal organs. EA commonly affected biological networks involved in cytoskeleton and cell adhesion, and also regulated unique process networks in specific organs, such as γ-aminobutyric acid-ergic neurotransmission in brain and inflammation process in lung. In addition, EA affected the expression of genes related to various diseases, such as neurodegenerative diseases in brain and obstructive pulmonary diseases in lung.

Conclusions

This report applied, for the first time, a global comprehensive genome-wide approach to analyze the gene expression profiling of acupunctured site and internal organs after EA stimulation. The connection between gene expression signatures, biological processes, and diseases might provide a basis for prediction and explanation on the therapeutic potentials of acupuncture in organs.

The Effect of Transcutaneous Electrical Acupoint Stimulation on Inflammatory Response in Patients Undergoing Limb Ischemia-Reperfusion

Reperfusion after tourniquet use can induce inflammation and cause remote organ injury. We evaluated the therapeutic effect of transcutaneous electrical acupoint stimulation (TEAS) on inflammatory mediators and lung function in patients receiving lower limb tourniquets. Forty patients undergoing unilateral lower extremity surgery with tourniquet were randomly assigned to two groups: the TEAS group and ischemia-reperfusion (I/R) group. The C-C motif chemokine ligand 2 (CCL2), C-X-C motif chemokine ligand 8 (CXCL8), interleukin-1 (IL-1), interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor-α (TNF-α), and arterial blood gas analysis were measured preoperatively and 6 h after tourniquet removal. The levels of CXCL8, IL-1, IL-6, TNF-α, and CCL2 were significantly increased compared to baseline values in both groups, but the increase was significantly smaller in the TEAS group. In the TEAS group, the partial pressure of oxygen and arterial-alveolar oxygen tension ratio were significantly decreased, and the alveolar-arterial oxygen tension difference and respiratory index were significantly increased, compared to those in the I/R group at 6 h after reperfusion. In conclusion, TEAS diminished the upregulation of proinflammatory factors in response to lower limb ischemia-reperfusion and improved pulmonary gas exchange.