Electroacupuncture Inhibits Inflammatory Edema and Hyperalgesia Through Regulation of Cyclooxygenase Synthesis in Both Peripheral and Central Nociceptive Sites

Effects and mechanisms of acupuncture on women related health

Globally, public health interventions have resulted in a 30-year increase in women's life expectancy. However, women's health has not increased when socioeconomic status is ignored. Women's health has become a major public health concern, for those women from developing countries are still struggling with infectious and labor-related diseases, and their counterparts in developed countries are suffering from physical and psychological disorders. In recent years, complementary and alternative medicine has attracted wide attentions with regards to maintaining women's health. Acupuncture, a crucial component of traditional Chinese medicine, has been used to treat many obstetric and gynecological diseases for thousands of years due to its analgesic and anti-inflammatory effects and its effects on stimulating the sympathetic/parasympathetic nervous system. To fully understand the mechanism through which acupuncture exerts its effects in these diseases would significantly extend the list of available interventions and would allow for more reasonable advice to be given to general practitioners. Therefore, by searching PubMed and CNKI regarding the use of acupuncture in treating obstetric and gynecological diseases, we aimed to summarize the proven evidence of using acupuncture in maintaining women's health by considering both its effectiveness and the underlying mechanisms behind its effects.

The Role of Acupuncture and Its Related Mechanism in Treating Chronic Prostatitis/Chronic Pelvic Pain Syndrome

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is one of the most common diseases in urology, and its prevalence has been increasing, causing serious urogenital problems in men. Several targeted oral drug therapies exist to treat the pelvic pain experienced in this disease. However, these therapies may have potential adverse effects, and due to the unique location of the prostate, delivery of medications to the target lesion is difficult. Consequently, many patients seek alternative therapies. Acupuncture is a well-established treatment method in traditional Chinese medicine that can improve CP/CPPS symptoms and reduce pain. However, previous systematic reviews overlooked the significance of the characteristics and mechanisms of acupuncture therapy. This study aimed to summarize the characteristics and benefits of acupuncture therapy for CP/CPPS based on relevant literature and predict and analyze its related mechanisms.

Acupuncture in Zoological Companion Animals

Over the past years, the concept of pain management in veterinary medicine has evolved and led to the establishment of a new concept of multimodal approach to pain management, as the current standard of care. The use of multimodal analgesia combining pharmacologic and nonpharmacologic techniques not only helps optimize the quality and efficacy of analgesia but also may prevent the development of chronic or persistent pain. During the past decade, acupuncture has become more popular and evolved into one of the most used forms of integrative medicine interventions and nonpharmacologic therapeutic options for pain management in humans and animals in North America and Europe. There is ample evidence from basic and clinical research for acupuncture is effective in the treatment of acute and chronic pain by influencing neural networks of the nervous system. While in the modern days' veterinary acupuncture has been predominantly used in horses and dogs, its popularity in zoologic companion animals (ZCA) has increased in recent years as an adjunct therapy for treating musculoskeletal, neurologic, and gastrointestinal disorders due to its minimal invasiveness and low risk of adverse events. The integrative use of acupuncture has become even more important with the increasingly limited use of opiates in veterinary medicine due to the opiate crisis. The purpose of this article aims to provide guidance for using acupuncture for pain management in ZCA in clinical practice, based on available information and recommendations from experienced veterinary acupuncturists.

The efficacy and mechanism of acupuncture in the treatment of male infertility: A literature review

Fertility, a social, cultural, and medical issue, has aroused public attention because of its potential to predict future health. In recent years, the incidence of male infertility has increased significantly, and various risk factors, such as congenital factors, acquired factors, and idiopathic factors, have led to this situation. Male infertility causes substantial psychological and social distress in patients. With the implementation of the two-child policy, male infertility has brought enormous psychological and social pressure and huge economic burden to patients and the healthcare system. This has attracted the attention of not only men of childbearing age but also many male experts. The conventional therapeutic approaches for treating male infertility, including drugs, varicocele surgery, intrauterine insemination, in vitro fertilization, and intracytoplasmic sperm injection, can restore fertility to a certain extent, but their efficacy is far from satisfactory, not to mention some adverse events. Therefore, acupuncture has been chosen by many men to treat their infertility and produced significant effects. In the present paper, the efficacy and mechanism of acupuncture in the treatment of male infertility were analyzed from different perspectives such as regulating hormone secretion, reducing inflammation, and improving semen parameters. The existing literature shows that acupuncture can effectively treat male infertility.

Efficacy of Acupuncture for Chronic Prostatitis/Chronic Pelvic Pain Syndrome : A Randomized Trial

BACKGROUND

Acupuncture has promising effects on chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), but high-quality evidence is scarce.

OBJECTIVE

To assess the long-term efficacy of acupuncture for CP/CPPS.

DESIGN

Multicenter, randomized, sham-controlled trial. (ClinicalTrials.gov: NCT03213938).

SETTING

Ten tertiary hospitals in China.

PARTICIPANTS

Men with moderate to severe CP/CPPS, regardless of prior exposure to acupuncture.

INTERVENTION

Twenty sessions of acupuncture or sham acupuncture over 8 weeks, with 24-week follow-up after treatment.

MEASUREMENTS

The primary outcome was the proportion of responders, defined as participants who achieved a clinically important reduction of at least 6 points from baseline on the National Institutes of Health Chronic Prostatitis Symptom Index at weeks 8 and 32. Ascertainment of sustained efficacy required the between-group difference to be statistically significant at both time points.

RESULTS

A total of 440 men (220 in each group) were recruited. At week 8, the proportions of responders were 60.6% (95% CI, 53.7% to 67.1%) in the acupuncture group and 36.8% (CI, 30.4% to 43.7%) in the sham acupuncture group (adjusted difference, 21.6 percentage points [CI, 12.8 to 30.4 percentage points]; adjusted odds ratio, 2.6 [CI, 1.8 to 4.0]; P < 0.001). At week 32, the proportions were 61.5% (CI, 54.5% to 68.1%) in the acupuncture group and 38.3% (CI, 31.7% to 45.4%) in the sham acupuncture group (adjusted difference, 21.1 percentage points [CI, 12.2 to 30.1 percentage points]; adjusted odds ratio, 2.6 [CI, 1.7 to 3.9]; P < 0.001). Twenty (9.1%) and 14 (6.4%) adverse events were reported in the acupuncture and sham acupuncture groups, respectively. No serious adverse events were reported.

LIMITATION

Sham acupuncture might have had certain physiologic effects.

CONCLUSION

Compared with sham therapy, 20 sessions of acupuncture over 8 weeks resulted in greater improvement in symptoms of moderate to severe CP/CPPS, with durable effects 24 weeks after treatment.

PRIMARY FUNDING SOURCE

China Academy of Chinese Medical Sciences and the National Administration of Traditional Chinese Medicine.

Histological evaluation of the effect of low-frequency electric stimulation on healing Achilles tendons in rats

PURPOSE

Histologically evaluate the effects of low frequency electrical stimulation in the treatment of Achilles tendon injuries in rats.

METHODS

Thirty-four rats underwent Achilles tendon tenotomy and tenorrhaphy. They were randomly allocated in two groups. Half of the sample constituted the experiment group, whose lesions were stimulated with 2 Hz, nonpolarized current and 1 mA, for 14 days. The other animals formed the control group. They were evaluated at 2, 4 and 6 weeks. The histological study was carried out, the collagen density and the wound maturity index were measured.

RESULTS

The healing score was higher in the group stimulated at the 6th week (p = 0.018). The density collagen 1 was higher in the group treated at the three times (p = 0.004) and that collagen 3 was higher in the group treated at 6 weeks (p = 0.004). Together, collagen 1 and 3 were higher in the group stimulated at 4 and 6 weeks (p = 0.009, p = 0.004). The maturity index was higher in this group at the three moments (p = 0.017 p = 0.004 and p = 0.009).

CONCLUSION

Low frequency electric stimulation improved healing and increased the quantity of collagen.

Tensiometric evaluation of the effect of lowfrequency electric stimulation on healing Achilles tendons in rats

PURPOSE

To evaluate the effects of low-frequency electric stimulation on biomechanics following surgical treatment of the Achilles tendon in rats.

METHODS

Forty-two rats were divided into two groups. One was given electric stimulation and the other was not. All were submitted to Achilles tenotomy and tenorrhaphy performed with a modified Kessler stitch. The experiment group underwent electric stimulation with 2 Hz, a nonpolarized current of 1 mA intensity for 14 days. The animals were euthanized at 2, 4 and 6 weeks for the biomechanical study.

RESULTS

The work performed, that is, the tendon's capacity to absorb energy until rupture, was greater in the electrically stimulated group in the 2nd (p = 0.032) and in the 6th week (p = 0.010). The maximum tension, which is the capacity to support a load, was higher in the treated group in the 2nd (p = 0.030) and the 6th week (p = 024). These results indicate greater resistance of the electrically stimulated tendons. An analysis of the elastic module showed no differences.

CONCLUSION

Low-frequency electric stimulation increased the resistance of the tendons at 2 and 6 weeks of evolution in rats.

Dry Needling and Acupuncture in Treatment of Dance-Related Injuries, MD, and PT Perspectives

Dancers frequently present to health care professionals with musculoskeletal impairments. The role of the health care practitioner, whether physician, physical therapist, or acupuncturist, is to decrease pain and restore function in the short term and to restore adaptive potential and neural connectivity in the long term. When dysfunction is treated, pain improves. Acupuncture and dry needling improve tissue perfusion by improving vasomotor control and can improve strength by removing motor inhibition. Acupuncture and dry needling are safe, complementary modalities aimed at improving the function of the dancer.

Acupuncture for Post-stroke Shoulder-Hand Syndrome: A Systematic Review and Meta-Analysis

Background: Shoulder-hand syndrome (SHS) is prevalent in hemiplegic patients after stroke. Potential benefits of acupuncture were shown in recent clinical trials. This systematic review aimed to comprehensively evaluate the safety and efficacy of acupuncture for SHS in stroke patients.

Methods: Five English databases (PubMed, Embase, CINAHL, CENTRAL, and AMED) and four Chinese databases (CBM, CNKI, CQVIP, and Wanfang) were searched from their inceptions to January 2019. Randomized, controlled trials that evaluated the add-on effects of acupuncture to rehabilitation for post-stroke SHS were identified.

Results: Thirty-eight studies involving 3,184 participants fulfilled the eligible criteria and were included in the review. The overall meta-analysis showed that acupuncture combined with rehabilitation significantly improved motor function (upper-limb Fugl-Meyer Assessment (FMA): 34 studies, mean difference (MD) 8.01, 95% confidence interval (CI) [6.69,9.33]), and reduced pain (visual analog scale (VAS): 25 studies, MD −1.59, 95%CI [−1.86,−1.32]). It also improved activities of daily living (ADL) when compared with rehabilitation alone (ADL: 11 studies, MD 9.99, 95%CI [5.91,14.06]). However, the certainty of evidence of all these outcomes was assessed as “low.” Subgroup analyses of acupuncture stimulation types and treatment duration all showed significant add-on effects comparing with rehabilitation alone. The safety of acupuncture was unclear because there is a lack of detailed reporting of adverse events in most of the included studies.

Conclusions: Acupuncture therapy seems effective for motor function, pain relief and activities of daily living in stroke patients with mild SHS, when it is used in combination with rehabilitation. The low certainty of evidence downgrades our confidence in making recommendations to clinical practice.

A Hypothesis for the Anti-Inflammatory and Mechanotransduction Molecular Mechanisms Underlying Acupuncture Tendon Healing

A previous study demonstrated that acupuncture increases the synthesis and reorganisation of collagen molecules in rat tendons after injury. Clinical studies have shown that acupuncture improves pain and functional activity in patients with tendinopathy. However, the molecular mechanisms underlying these effects are unknown. Recent studies have shown that acupuncture can modulate both anti-inflammatory (AI) and mechanotransduction (MT) molecular pathways. Moreover, the modulation of these pathways can increase type I collagen synthesis, which is the main factor that influences tendon biomechanical properties. Our hypothesis is that acupuncture increases synthesis and subsequent reorganisation of type I collagen during tendon healing by concomitant modulation of the Toll-like receptor-nuclear factor-κB AI pathway, the mitogen-activated protein kinases pathway and the Rho/Rac-F-actin MT pathway. Increased collagen synthesis and reorganisation requires that at least one acupoint is anatomically connected with the site of the injury because of the local tenoblast MT mechanism. Confirmation of this hypothesis will increase the knowledge of acupuncture modulation of the previously mentioned molecular pathways, and such confirmation may also help to establish the relationships between the different types of acupuncture needle stimulation and the influence of acupuncture stimuli on pathway activity levels. In addition, the downstream therapeutic effects of acupuncture therapy may be established. This hypothesis can be verified in a rat tendon healing model, and subsequent clinical protocols for tendon healing can be developed and evaluated as standalone therapies or as a component of a combination therapy.

Effectiveness of Acupuncture and Electroacupuncture for Chronic Neck Pain: A Systematic Review and Meta-Analysis

The aim of this systematic review was to assess evidence from randomized controlled trials (RCTs) on the effectiveness and safety of acupuncture and electroacupuncture in patients with chronic neck pain. We searched nine databases including Chinese, Japanese and Korean databases through 30 July 2016. The participants were adults with chronic neck pain and were treated with acupuncture or electroacupuncture. Eligible trials were those with intervention groups receiving acupuncture and electroacupuncture with or without active control, and control groups receiving other conventional treatments such as physical therapy or medication. Outcomes included pain intensity, disability, quality of life (QoL) and adverse effects. For statistical pooling, the standardized mean difference (SMD) and its 95% confidence interval (CI) were calculated using a fixed-effects model. Sixteen RCTs were selected. The comparison of the sole acupuncture group and the active control group did not come out with a significant difference in pain (SMD 0.24, 95% CI [Formula: see text]0.27–0.75), disability (SMD 0.51, 95% CI [Formula: see text]0.01–1.02), or QoL (SMD [Formula: see text]0.37, 95% CI [Formula: see text]1.09–0.35), showing a similar effectiveness of acupuncture with active control. When acupuncture was added into the control group, the acupuncture add-on group showed significantly higher relief of pain in studies with unclear allocation concealment (SMD [Formula: see text]1.78, 95% CI [Formula: see text]2.08–[Formula: see text]1.48), but did not show significant relief of pain in studies with good allocation concealment (SMD [Formula: see text]0.07, 95% CI [Formula: see text]0.26–0.12). Significant relief of pain was observed when the sole electroacupuncture group was compared to the control group or electroacupuncture was added onto the active control group, but a lot of the results were evaluated to have low level of evidence, making it difficult to draw clear conclusions. In the result reporting adverse effects, no serious outcome of adverse event was confirmed. Acupuncture and conventional medicine for chronic neck pain have similar effectiveness on pain and disability when compared solely between the two of them. When acupuncture was added onto conventional treatment it relieved pain better, and electroacupuncture relieved pain even more. It is difficult to draw conclusion because the included studies have a high risk of bias and imprecision. Therefore better designed large-scale studies are needed in the future.

Electroacupuncture pretreatment attenuates spinal cord ischemia-reperfusion injury via inhibition of high-mobility group box 1 production in a LXA4 receptor-dependent manner

Paraplegia caused by spinal cord ischemia is a severe complication following surgeries in the thoracic aneurysm. HMGB1 has been recognized as a key mediator in spinal inflammatory response after spinal cord injury. Electroacupuncture (EA) pretreatment could provide neuroprotection against cerebral ischemic injury through inhibition of HMGB1 release. Therefore, the present study aims to test the hypothesis that EA pretreatment protects against spinal cord ischemia-reperfusion (I/R) injury via inhibition of HMGB1 release. Animals were pre-treated with EA stimulations 30min daily for 4 successive days, followed by 20-min spinal cord ischemia induced by using a balloon catheter placed into the aorta. We found that spinal I/R significantly increased mRNA and cytosolic protein levels of HMGB1 after reperfusion in the spinal cord. The EA-pretreated animals displayed better motor performance after reperfusion along with the decrease of apoptosis, HMGB1, TNF-α and IL-1β expressions in the spinal cord, whereas these effects by EA pretreatment was reversed by rHMGB1 administration. Furthermore, EA pretreatment attenuated the down-regulation of LXA₄ receptor (ALX) expression induced by I/R injury, while the decrease of HMGB1 release in EA-pretreated rats was reversed by the combined BOC-2 (an inhibitor of LXA₄ receptor) treatment. In conclusion, EA pretreatment may promote spinal I/R injury through the inhibition of HMGB1 release in a LXA₄ receptor-dependent manner. Our data may represent a new therapeutic technique for treating spinal cord ischemia-reperfusion injury.

Sphenopalatine Ganglion Acupuncture Improves Nasal Ventilation and Modulates Autonomic Nervous Activity in Healthy Volunteers: A Randomized Controlled Study

The study aimed to assess the effects of Sphenopalatine ganglion (SPG) acupuncture on nasal ventilation function and autonomic nervous system in health volunteers. 39 healthy subjects were randomly assigned to either active SPG acupuncture group (AA group) or sham-SPG acupuncture group (SA group). All subjects were assessed for self-reported nasal ventilation, nasal patency (nasal airway resistance (NAR) and nasal cavity volume (NCV), exhaled nasal nitric oxide (nNO), and neuropeptides (substance P(SP), vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY)) in nasal secretions at baseline, 30 minutes, 2 hours, and 24 hours after acupuncture. Significantly more subjects in AA group reported improvements in nasal ventilation at all time points after acupuncture, compared to SA group. NAR and NCV were also significantly lower in AA group than SA group. The level of nNO in AA group was significantly decreased after 24 hours compared to SA group. The level of NPY was significantly increased in AA group at 30 minutes and 2 hours compared to baseline and SA group. The levels of SP and VIP were not significantly different in the two groups. We concluded that SPG acupuncture could help to improve nasal ventilation by increasing sympathetic nerve excitability in healthy volunteers.

The Effects of Yin, Yang and Qi in the Skin on Pain

The most effective and safe treatment site for pain is in the skin. This chapter discusses the reasons to treat pain in the skin. Pain is sensed in the skin through transient receptor potential cation channels and other receptors. These receptors have endogenous agonists (yang) and antagonists (yin) that help the body control pain. Acupuncture works through modulation of these receptor activities (qi) in the skin; as do moxibustion and liniments. The treatment of pain in the skin has the potential to save many lives and improve pain therapy in most patients.

Anti-inflammatory effect of laser acupuncture in ST36 (Zusanli) acupoint in mouse paw edema

Low-level laser therapy (LLLT) in acupuncture is a low-power laser applied to acupoints for providing luminous energy, capable to produce photobiological induction that results in biochemical, bioelectric, and bioenergetic effects. ST36 (Zusanli) is a point of acupuncture commonly used for treatment of several pathological alterations, such as inflammation, acute pain, and gastrointestinal disorders. In this study, we evaluated the anti-inflammatory effect of LLLT (830 nm, 4 J/cm(2)) in ST36 acupoint through the model of carrageenan-induced paw edema in mice and the possible mechanisms involved. Female Swiss mice were treated with LLLT in ST36 before the paw edema induction, which was measured by means of a digital micrometer and the temperature through a high-resolution digital thermograph. After this, the levels of reactive oxygen species (ROS), lipid hydroperoxides (LOOH), and reduced glutathione (GSH) were quantified. In another set of experiments, the paw edema was induced by bradykinin, histamine, and prostaglandin E2 (PGE2). LLLT in ST36 acupoint significantly inhibited the edema formation for 4 h after the carrageenan injection and reduced the paw temperature in 10 %. Furthermore, LLLT also reduced the levels of ROS (55 %) and LOOH (50 %) but, however, did not alter the GSH levels. LLLT in ST36 reduced the paw edema induced by bradykinin (30 min, 6 %, 60 min, 7 %), histamine (30 min, 11 %), and PGE2 (90 min, 10 %, 120 min, 16 %). In conclusion, these results prove that LLLT in ST36 acupoint produces a relevant anti-inflammatory effect, reducing edema, temperature, and free radicals levels in mice paw.

Acupuncture for seasonal allergic rhinitis: a randomized controlled trial

BACKGROUND

Seasonal allergic rhinitis (SAR) is a common condition with relatively high prevalence in Australia. It causes a significant impact on sufferers' quality of life (QoL). Meta-analysis has shown that the efficacy of acupuncture for SAR is uncertain.

OBJECTIVE

To evaluate the efficacy and safety of 12 sessions of acupuncture treatment during 4 weeks for SAR in a randomized, subject- and assessor-blinded, sham-controlled trial conducted during the pollen seasons in 2009 through 2011 in Melbourne.

METHODS

Patients diagnosed with SAR and confirmed allergic to rye grass pollen were randomly allocated to receive real acupuncture (RA) or sham acupuncture (SA) treatment. RA was delivered manually, whereas SA involved superficial needling at non-acupoints without additional stimulation. Severity of SAR symptoms was the primary outcome measurement. Secondary outcomes were QoL, global change, SAR-related medication usage, and adverse events. Analysis of covariance using pollen count as a covariate was used to analyze outcome data.

RESULTS

A total of 175 participants were included in this trial. RA was significantly better than SA for decreasing SAR symptom severity (sneezing, mean difference -0.28, 95% confidence interval -0.51 to -0.05; itchiness of ears and palate, mean difference -0.40, 95% confidence interval -0.69 to -0.11) at the end of treatment and improving participants' QoL at the end of the treatment and follow-up phases. Furthermore, the acupuncture treatment was safe and well tolerated.

CONCLUSION

Four weeks of acupuncture treatment is a safe and effective option for clinical management of SAR in the Melbourne area for patients' symptom relief and QoL improvement.

Acupuncture Increases the Diameter and Reorganisation of Collagen Fibrils during Rat Tendon Healing

Background

Our previous study showed that electroacupuncture (EA) increases the concentration and reorganisation of collagen in a rat model of tendon healing. However, the ultrastructure of collagen fibrils after acupuncture is unknown.

Objectives

To assess the effect of acupuncture protocols on the ultrastructure of collagen fibrils during tendon healing.

Methods

Sixty-four rats were divided into the following groups: non-tenotomised (normal group), tenotomised (teno group), tenotomised and subjected to manual acupuncture at ST36 (ST36 group), BL57 (BL57 group) and ST36+BL57 (SB group) and EA at ST36+BL57 (EA group). The mass-average diameter (MAD) and the reorganisation of collagen fibril diameters were determined during the three phases of tendon healing (at 7, 14 and 21 days).

Results

The MAD increased during the three phases of healing in the SB group. In the EA group, MAD increased initially but was reduced at day 21. The reorganisation of collagen fibrils was improved in the EA and SB groups at days 14 and 21, respectively. EA at day 21 appeared to reduce the reorganisation.

Conclusions

These results indicate that the use of EA up to day 14 and manual acupuncture at ST36+BL57 up to day 21 improve the ultrastructure of collagen fibrils, indicating strengthening of the tendon structure. These data suggest a potential role for acupuncture in rehabilitation protocols.

Electroacupuncture mediates extracellular signal-regulated kinase 1/2 pathways in the spinal cord of rats with inflammatory pain

Background

Activation of extracellular signal-regulated kinase1/2 (ERK1/2) in dorsal horn of the spinal cord by peripheral inflammation is contributed to inflammatory pain hypersensitivity. Although electroacupuncture (EA) has been widely used to alleviate various kinds of pain, the underlying mechanism of EA analgesia requires further investigation. This study investigated the relationship between EA-induced analgesia and ERK signaling involved in pain hypersensitivity.

Methods

The rats were randomly divided into control, model, EA and sham EA groups. Inflammatory pain model was induced by injecting of 100 μl Complete Freund’s adjuvant (CFA) into the plantar surface of a hind paw. Rats in the EA group were treatment with EA (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1-2 mA) at 5.5 h, 24.5 h and 48.5 h. Paw withdrawal thresholds (PWTs) were measured before modeling and at 5 h, 6 h, 25 h and 49 h after CFA injection. Rats were killed and ipsilateral side of the lumbar spinal cords were harvested for detecting the expressions of p-ERK1/2, Elk1, COX-2, NK-1 and CREB by immunohistochemistry, real-time PCR, western blot analysis and EMSA. Finally, the analgesic effect of EA plus U0126, a MEK (ERK kinase) inhibitor, on CFA rats was examined.

Results

Inflammatory pain was induced in rats by hindpaw injection of CFA and significantly increased phospho-ERK1/2 positive cells and protein levels of p-ERK1/2 in the ipsilateral spinal cord dorsal horn (SCDH). CFA up-regulated of cyclooxygenase-2 (COX-2) mRNA and protein expression at 6 h after injection and neurokinin-1 receptor (NK-1) expression at 49 h post-injection, in the SCDH. EA, applied to Zusanli (ST36) and Kunlun (BL60), remarkably increased the pain thresholds of CFA injected rats, significantly suppressed ERK1/2 activation and COX-2 protein expression after a single treatment, and decreased NK-1 mRNA and protein expression at 49 h. EA decreased the DNA binding activity of cAMP response element binding protein (CREB), a downstream transcription factor of ERK1/2, at 49 h after CFA injection. Moreover, EA and U0126 synergistically inhibited CFA-induced allodynia.

Conclusions

The present study suggests that EA produces analgesic effect by preventing the activation of ERK1/2-COX-2 pathway and ERK1/2-CREB-NK-1 pathway in CFA rats.

Electroacupuncture exerts an anti-inflammatory effect in a rat tissue chamber model of inflammation via suppression of NF-κB activation

OBJECTIVE

Electroacupuncture (EA) has beneficial effects in patients with various inflammatory diseases. However, the underlying mechanism remains unclear. As the kappa B inhibitor/nuclear factor-kappa B (IκB/NF-κB) pathway exerts a pivotal role in the mammalian immune response, we examined the involvement of the IκB/NF-κB pathway in EA-induced anti-inflammation.

METHODS

Ninety tissue chamber implanted rats were randomly divided into control (C), model (M) and EA (E) groups. Physiological saline and human recombinant interleukin-1β (hr IL-1β) were injected into the rats in groups C and M, respectively, and EA treatment was applied to the rats in group E after IL-1β injection. Nuclear staining of p65 (a subunit of NF-κB) was quantified in the exudate cells by immunohistochemical analysis and IκBα expression in the cytoplasm was quantified by western blot analysis.

RESULTS

Our results showed that, compared with group C, the percentage of cells with nuclear-localised p65 was increased in group M by 71.3%, 50.7% and 33.1% at 1, 5 and 24 h time points (p<0.01), respectively. This increase was fully inhibited in group E at 5 and 24 h time points (p<0.01). The expression of IκBα was stably enhanced in group M (p<0.05) during the test period. Compared with group M, greater expression of IκBα in group E was only observed at the 1 h time point (p<0.01).

CONCLUSIONS

Collectively, our data suggest that EA inhibits the nuclear translocation of p65 and increases the expression of IκBα, which leads to the suppression of NF-κB activation in a rat tissue chamber model of inflammation.

Mechanisms of acupuncture-electroacupuncture on persistent pain

In the last decade, preclinical investigations of electroacupuncture mechanisms on persistent tissue injury (inflammatory), nerve injury (neuropathic), cancer, and visceral pain have increased. These studies show that electroacupuncture activates the nervous system differently in health than in pain conditions, alleviates both sensory and affective inflammatory pain, and inhibits inflammatory and neuropathic pain more effectively at 2 to 10 Hz than at 100 Hz. Electroacupuncture blocks pain by activating a variety of bioactive chemicals through peripheral, spinal, and supraspinal mechanisms. These include opioids, which desensitize peripheral nociceptors and reduce proinflammatory cytokines peripherally and in the spinal cord, and serotonin and norepinephrine, which decrease spinal N-methyl-D-aspartate receptor subunit GluN1 phosphorylation. Additional studies suggest that electroacupuncture, when combined with low dosages of conventional analgesics, provides effective pain management which can forestall the side effects of often-debilitating pharmaceuticals.

Effect of Electroacupuncture Intervention on Expression of CGRP, SP, COX-1, and PGE2 of Dorsal Portion of the Cervical Spinal Cord in Rats with Neck-Incision Pain

The present study was aimed to determine if cervicospinal substance P (SP) and its neurokinin-1 receptor (NK-1R), calcitonin gene-related peptide (CGRP), cyclooxygenase-1 (COX-1), and prostaglandin E2 (PGE2) were involved in electroacupuncture (EA) analgesia in neck-incision pain rats. EA intervention was applied to bilateral Futu (LI18), Hegu (LI4)-Neiguan (PC6), and Zusanli (ST36)-Yanglingquan (GB34) for 30 min. Cervicospinal SP and CGRP immunoactivity was detected by immunofluorescence technique, NK-1R and COX-1 protein and mRNA expression levels were determined using Western blot and real-time PCR, respectively, and PGE2 content was measured using ELISA. Outcomes indicated that EA of EA-LI18 and LI4-PC6 (not ST36-GB34) significantly suppressed neck-incision induced decrease of thermal pain threshold (P < 0.05). EA stimulation of LI18 and LI4-PC6 markedly inhibited neck-incision induced upregulation of SP and CGRP immunoactivity, NK-1 R and COX-1 mRNA and protein expression levels, as well as the increase of PGE2 content in the dorsal cervicospinal cord (P < 0.05). These findings showed that LI18 and LI4-PC6 EA stimulation-induced downregulation of SP, CGRP, NK-1R, COX-1, and PGE2 levels in the dorsal cervicospinal cord may contribute to their effects in relieving neck-incision pain. This study highlights the targets of EA intervention for reducing post-thyroid-surgery pain for the first time.

Intervention of electroacupuncture on spinal p38 MAPK/ATF-2/VR-1 pathway in treating inflammatory pain induced by CFA in rats

Background

Previous studies have demonstrated that p38 MAPK signal transduction pathway plays an important role in the development and maintenance of inflammatory pain. Electroacupuncture (EA) can suppress the inflammatory pain. However, the relationship between EA effect and p38 MAPK signal transduction pathway in inflammatory pain remains poorly understood. It is our hypothesis that p38 MAPK/ATF-2/VR-1 and/or p38 MAPK/ATF-2/COX-2 signal transduction pathway should be activated by inflammatory pain in CFA-injected model. Meanwhile, EA may inhibit the activation of p38 MAPK signal transduction pathway. The present study aims to investigate that anti-inflammatory and analgesic effect of EA and its intervention on the p38 MAPK signal transduction pathway in a rat model of inflammatory pain.

Results

EA had a pronounced anti-inflammatory and analgesic effect on CFA-induced chronic inflammatory pain in rats. EA could quickly raise CFA-rat’s paw withdrawal thresholds (PWTs) and maintain good and long analgesic effect, while it subdued the ankle swelling of CFA rats only at postinjection day 14. EA could down-regulate the protein expressions of p-p38 MAPK and p-ATF-2, reduced the numbers of p-p38 MAPK-IR cells and p-ATF-2-IR cells in spinal dorsal horn in CFA rats, inhibited the expressions of both protein and mRNA of VR-1, but had no effect on the COX-2 mRNA expression.

Conclusions

The present study indicates that inhibiting the activation of spinal p38 MAPK/ATF-2/VR-1 pathway may be one of the main mechanisms via central signal transduction pathway in the process of anti-inflammatory pain by EA in CFA rats.

The anti-inflammatory effects of acupuncture and their relevance to allergic rhinitis: a narrative review and proposed model

Classical literature indicates that acupuncture has been used for millennia to treat numerous inflammatory conditions, including allergic rhinitis. Recent research has examined some of the mechanisms underpinning acupuncture's anti-inflammatory effects which include mediation by sympathetic and parasympathetic pathways. The hypothalamus-pituitary-adrenal (HPA) axis has been reported to mediate the antioedema effects of acupuncture, but not antihyperalgesic actions during inflammation. Other reported anti-inflammatory effects of acupuncture include an antihistamine action and downregulation of proinflammatory cytokines (such as TNF-α, IL-1β, IL-6, and IL-10), proinflammatory neuropeptides (such as SP, CGRP, and VIP), and neurotrophins (such as NGF and BDNF) which can enhance and prolong inflammatory response. Acupuncture has been reported to suppress the expression of COX-1, COX-2, and iNOS during experimentally induced inflammation. Downregulation of the expression and sensitivity of the transient receptor potential vallinoid 1 (TRPV1) after acupuncture has been reported. In summary, acupuncture may exert anti-inflammatory effects through a complex neuro-endocrino-immunological network of actions. Many of these generic anti-inflammatory effects of acupuncture are of direct relevance to allergic rhinitis; however, more research is needed to elucidate specifically how immune mechanisms might be modulated by acupuncture in allergic rhinitis, and to this end a proposed model is offered to guide further research.

Effects of different electroacupuncture scheduling regimens on murine bone tumor-induced hyperalgesia: sex differences and role of inflammation

Previous studies have shown that electroacupuncture (EA) is able to reduce hyperalgesia in rodent models of persistent pain, but very little is known about the analgesic effects and potential sex differences of different EA treatment regimens. In the present study, we examined the effects of five different EA treatments on tumor-induced hyperalgesia in male and female mice. EA applied to the ST-36 acupoint either twice weekly (EA-2X/3) beginning on postimplantation day (PID) 3 or prophylactically three times prior to implantation produced the most robust and longest lasting antinociceptive effects. EA treatment given once per week beginning at PID 7 only produced an antinociceptive effect in female animals. The analgesic effect of EA-2X/3 began earlier in males, but lasted longer in females indicating sex differences in EA. We further demonstrate that EA-2X/3 elicits a marked decrease in tumor-associated inflammation as evidenced by a significant reduction in tumor-associated neutrophils at PID 7. Moreover, EA-2X/3 produced a significant reduction in tumor-associated PGE₂ as measured in microperfusate samples. Collectively, these data provide evidence that EA-2X/3 treatment reduces tumor-induced hyperalgesia, which is associated with a decrease in tumor-associated inflammation and PGE₂ concentration at the tumor site suggesting possible mechanisms by which EA reduces tumor nociception.

Electroacupuncture increases the concentration and organization of collagen in a tendon healing model in rats

The aim of this study was to investigate the effect of electroacupuncture (EA) on the composition and organization of the extracellular matrix of the rat Achilles tendon after a partial transection during the proliferative phase of healing. Wistar rats were divided into three groups: rats that were not tenotomized (G1), tenotomized rats (G2), and rats that were tenotomized and submitted to EA (G3). EA was applied 15 days after injury at the ST36 and BL57 acupoints for 20 min, three times per week on alternate days for a total of six sessions. Biochemical analyses were performed using non-collagenous proteins, glycosaminoglycans, and hydroxyproline quantifications. An analysis of metalloproteinase-2 was carried out by zymography. The general organization of the extracellular matrix and the metachromasy of the tendons were analyzed under light microscopy. The organization of the bundles of collagen fibers was analyzed by birefringence analysis. The results showed that EA did not alter the concentration of non-collagenous proteins or glycosaminoglycans or the enzymatic activity of metalloproteinase-2 in the transected tendons. However, the concentration of hydroxyproline was significantly increased when these tendons were treated by EA. The analysis of birefringence showed a higher organization of collagen fibers in the group treated by EA. These results indicate, for the first time, that EA may offer therapeutic benefits for the treatment of tendon injuries by increasing the concentration of collagen and by inducing a better molecular organization of the collagen fibers, which may improve the mechanical strength of the tendon after injury.

Antinociceptive and anti-inflammatory effects of electroacupuncture on experimental arthritis of the rat temporomandibular joint

This study investigated the antinociceptive and anti-inflammatory effects of electroacupuncture (EA) on zymosan-induced acute arthritis of the rat temporomandibular joint (TMJ). Male Wistar rats were injected with saline or zymosan (control group; 2 mg) into the left TMJ. Low frequency EA (10 Hz, 30 min) was performed at acupoints (LI4, LI11, ST36, ST44) or sham points 2 h after or 1 h before zymosan administration. Mechanical hypernociception was accessed by the electronic Von Frey method after zymosan administration. Rats were sacrificed 6 h after zymosan administration and the joint was removed for histopathological analysis, myeloperoxidase activity assessment, vascular permeability observations, and immunohistochemical verification of inflammatory mediators. The results showed that EA inhibited zymosan-induced hypernociception, compared with the control group and with the sham group (p < 0.05). The results showed that EA inhibited inflammatory parameters such as neutrophil migration, vascular permeability, and tumour necrosis factor α (TNF-α), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) expression in the TMJ compared with the sham group (p < 0.05). Histopathological analysis showed that EA significantly inhibited edema and periarticular infiltration (p < 0.05) compared with the control and sham groups. EA at acupoints produced antinociceptive and anti-inflammatory effects on zymosan-induced arthritis in the rat TMJ.

A randomized controlled trial of auricular transcutaneous electrical nerve stimulation for managing posthysterectomy pain

Background. A patient- and assessor-blinded randomized controlled trial was conducted to examine the effectiveness of auricular transcutaneous electrical nerve stimulation (TENS) in relieving posthysterectomy pain. Method. Forty-eight women who had undergone a total abdominal hysterectomy were randomly assigned into three groups (n = 16 each) to receive either (i) auricular TENS to therapeutic points (the true TENS group), (ii) auricular TENS to inappropriate points (the sham TENS group), or (iii) 20 minutes of bed rest with no stimulation (the control group). The intervention was delivered about 24 hours after the operation. A visual analogue scale was used to assess pain while resting (VAS-rest) and upon huffing (VAS-huff) and coughing (VAS-cough), and the peak expiratory flow rate (PEFR) was assessed before and at 0, 15, and 30 minutes after the intervention. Result. As compared to the baseline, only the true TENS group reported a significant reduction in VAS-rest (P = .001), VAS-huff (P = .004), and VAS-cough (P = .001), while no significant reduction in any of the VAS scores was seen in the sham TENS group (all P > .05). In contrast, a small rising trend was observed in the VAS-rest and VAS-huff scores of the control group, while the VAS-cough score remained largely unchanged during the period of the study. A between-group comparison revealed that all three VAS scores of the true TENS group were significantly lower than those of the control group at 15 and 30 minutes after the intervention (all P < .02). No significant between-group difference was observed in PEFR at any point in time. Conclusion. A single session of auricular TENS applied at specific therapeutic points significantly reduced resting (VAS-rest) and movement-evoked pain (VAS-huff, VAS-cough), and the effects lasted for at least 30 minutes after the stimulation. The analgesic effects of auricular TENS appeared to be point specific and could not be attributed to the placebo effect alone. However, auricular TENS did not produce any significant improvement in the performance of PEFR.

Involvement of peripheral opioid receptors in electroacupuncture analgesia for carrageenan-induced hyperalgesia

Acupuncture is widely used to relieve pain; however, the mechanism underlying electroacupuncture analgesia (EAA) during inflammatory pain is unclear. We investigated whether endogenous peripheral opioid receptors participated in EAA during hyperalgesia elicited by carrageenan-induced inflammation. Moreover, we investigated which subtype of opioid receptor was involved in EAA. Carrageenan was subcutaneously administered by intraplanter (i.pl.) injection into the left hind paw. Nociceptive thresholds were measured using the paw pressure threshold (PPT). Rats received 3Hz electroacupuncture (EA) for 1h after carrageenan injection. The nonselective peripheral opioid receptor antagonist, naloxone methiodide, was administered by i.pl. injection of the inflamed paw 5min before EA. Also, animals received i.pl. or intravenous (i.v.) injection of selective antagonists against μ(D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-ThrNH2, CTOP), δ(naltrindole, NTI), or κ (nor-Binaltorphimine, nor-BNI) opioid receptors 1h before EA. PPT decreased significantly 3h after carrageenan injection. EA resulted in significant increases of PPT, moreover, PPT elevations persisted for 9h after carrageenan injection. PPT elevations produced by EA were antagonized by local i.pl. injection of naloxone methiodide at 3 and 5h after cessation of EA. NTI, nor-BNI and CTOP blocked EAA from immediately, 1h, and 3h after EA cessation, respectively. The EAA in the inflamed paw could not be blocked by i.v. injection of NTI, nor-BNI and CTOP. These findings suggest that peripheral μ, δ and κ receptors on peripheral nerve terminals are activated by EA, although there is a time difference among these activations.

Electroacupuncture relieves pain in men with chronic prostatitis/chronic pelvic pain syndrome: three-arm randomized trial

OBJECTIVES

To investigate the clinical effect of electroacupuncture (EA) for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS).

METHODS

We recruited 63 participants meeting the U.S. National Institutes of Health (NIH) consensus criteria for CP/CPPS. After the inclusion/exclusion criteria were applied, 39 men were randomized to 3 treatment groups: group 1, advice and exercise plus 12 sessions of EA; group 2, advice and exercise plus 12 sessions of sham EA (SEA); and group 3, advice and exercise alone (A&E) for 6 weeks. A total of 6 acupuncture points were used to stimulate the sacral nerve and release the piriformis muscle using an electrical pulse generator. Symptoms related to CP/CPPS were assessed using the NIH-Chronic Prostatitis Symptom Index (NIH-CPSI). Prostaglandin E(2) and beta-endorphin levels in postmassage urine samples were measured using an enzyme-linked immunosorbent assay.

RESULTS

At 6 weeks, the NIH-CPSI total score had decreased significantly in the EA group compared with the SEA and A&E groups (P < .001). On a subscale analysis of the NIH-CPSI, the EA group showed significant decreases in pain-related symptoms compared with the SEA and A&E groups (P < .01). All 12 EA participants experienced at least a 6-point decrease in the NIH-CPSI total score compared with 2 of 12 SEA participants (16.7%) and 3 of 12 A&E participants (25.0%; P < .0001). The mean prostaglandin E(2) level in the postmassage urine samples had significantly decreased in the EA group (P = .023). In contrast, it had increased in the other 2 groups.

CONCLUSIONS

In a 3-arm randomized trial investigating the clinical effects of EA on CP/CPPS, EA therapy proved to have independent therapeutic effects, particularly for pain relief superior to SEA or A&E therapy.

Disinhibitory involvement of the anterior cingulate cortex in the descending antinociceptive effect induced by electroacupuncture stimulation in rats

The present study was conducted to clarify the role of the anterior cingulate cortex (ACCX) in acupuncture analgesia. Experiments were performed on 35 female Wistar albino rats weighing about 300 g. Single unit recordings were made from ACCX neurons with a tungsten microelectrode. Descending ACCX neurons were identified by antidromic activation from electrical shocks applied to the ventral part of the ipsilateral PAG through a concentric needle electrode. Cathodal electroacupuncture stimulation of Ho-Ku (0.1 ms in duration, 45 Hz) for 15 min was done by inserting stainless steel needles bilaterally. An anodal silver-plate electrode (30 mm x 30 mm) was placed on the center of the abdomen. Naloxone (1.0 mg/kg, i.v.) was used to test whether changes of ACCX activities were induced by the endogenous opioid system. Data were collected from a total of 73 ACCX neurons. Forty-seven neurons had descending projection to the PAG, and the other 26 had no projections to the PAG. A majority of descending ACCX neurons were inhibited by electroacupuncture stimulation. By contrast, non-projection ACCX neurons were mainly unaffected by electroacupuncture. Naloxone did not reverse acupuncture effects on the changes of ACCX neuronal activities. Acupuncture stimulation had predominantly inhibitory effects on the activities of descending ACCX neurons. Since the functional connection between ACCX and PAG is inhibitory, electroacupuncture caused disinhibition of PAG neurons, whose activity is closely related to descending antinociception to the spinal cord. This disinhibitory effect elicited by acupuncture stimulation is thought to play a significant role in acupuncture analgesia.