Acupuncture ameliorates not only atopic dermatitis-like skin inflammation but also acute and chronic serotonergic itch possibly through blockade of 5-HT2 and 5-HT7 receptors in mice

Advances in GPCR-targeted drug development in dermatology

Achieving the efficacy and specificity of G-protein-coupled receptor (GPCR) targeting-drugs in the skin remains challenging. Understanding the molecular mechanism underlying GPCR dysfunction is crucial for developing targeted therapies. Recent advances in genetic, signal transduction, and structural studies have significantly improved our understanding of cutaneous GPCR functions in both normal and pathological states. In this review, we summarize recent discoveries of pathogenic GPCRs in dermal injuries, chronic inflammatory dermatoses, cutaneous malignancies, as well as the development of potent potential drugs. We also discuss targeting of cutaneous GPCR complexes via the transient receptor potential (TRP) channel and structure elucidation, which provide new opportunities for therapeutic targeting of GPCRs involved in skin disorders. These insights are expected to lead to more effective and specific treatments for various skin conditions.

Comparative efficacy of acupuncture point stimulation treatments for dialysis patients with uremic pruritus: a systematic review and network meta-analysis

Background

Uremic pruritus (UP) is a common complication of chronic kidney disease that causes sleep disturbances and increases all-cause mortality. Currently, the first-line medications for UP exhibit inadequate pruritus control with adverse effects. Various acupuncture point stimulation treatments (APSTs) have been shown to be effective as adjuvant therapies in UP, and a network meta-analysis can offer relative efficacy estimates for treatments for which head-to-head studies have not been performed.

Methods

We conducted a random-effects network meta-analysis on a consistency model to compare the different APSTs for UP. The primary outcomes were the mean visual analog scale (VAS) score and effectiveness rate (ER).

Results

The network meta-analysis retrieved 27 randomized controlled trials involving 1969 patients. Compared with conventional treatment alone, combination treatment with acupuncture (mean difference, -2.63; 95% confidence interval, -3.71 to -1.55) was the most effective intervention in decreasing VAS scores, followed by acupoint injection and massage (mean difference, -2.04; 95% confidence interval, -3.96 to -0.12). In terms of the ER, conventional treatment with acupuncture and hemoperfusion (risk ratio, 14.87; 95% confidence interval, 2.18 to 101.53) was superior to other therapeutic combinations. Considering the VAS score and ER, combination treatment with acupoint injection and massage showed benefits in treating UP.

Conclusion

Our network meta-analysis provided relative efficacy data for choosing the optimal adjuvant treatment for UP. Combined treatment with acupuncture was more effective than conventional treatment only and was the most promising intervention for treating UP.Systematic review registration: PROSPERO (CRD42023425739: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023425739).

Cimifugin Relieves Histamine-Independent Itch in Atopic Dermatitis via Targeting the CQ Receptor MrgprA3

Background: We previously found that cimifugin has a potent antiallergic inflammatory effect in atopic dermatitis (AD). However, whether cimifugin has an antipruritic effect in AD was unknown. Methods: Mouse scratching behavior tests were performed to verify the proposed antipruritic effect of cimifugin on DNFB- or FITC-mediated AD. Chloroquine (CQ)- and compound 48/80-evoked acute itch models were employed to clarify the effect of cimifugin on histamine-dependent or -independent itch. Intracellular calcium changes were assessed in a primary culture of mouse dorsal root ganglia (DRG) in response to pruritogen exposure with or without cimifugin treatment, including CQ, histamine, allyl-isothiocyanate (AITC), and capsaicin. Molecular docking and microscale thermophoresis (MST) assays were performed to predict and verify the binding ability and modes between cimifugin and the CQ receptor MrgprA3, respectively. Results: We found that cimifugin attenuates itch behaviors effectively in FITC-induced AD. Notably, cimifugin significantly alleviated acute itching behaviors induced by CQ but not compound 48/80 in vivo. Moreover, cimifugin remarkably inhibited CQ-evoked calcium influx in DRG cells but had no obvious effect on histamine-induced calcium influx. Nevertheless, cimifugin did not interfere with either AITC-stimulated TRPA1 activation- or capsaicin-stimulated TRPV1 activation-mediated calcium influx in DRG cells. Molecular docking predicted that CQ and cimifugin might share similar binding abilities and binding modes with MrgprA3. MST assay confirmed cimifugin directly targeting MrgprA3. Conclusion: The present study demonstrates that cimifugin has a potent antipruritic effect in AD with a histamine-independent mechanism via targeting the CQ receptor MrgprA3. Thus, cimifugin is a promising candidate antipruritic agent for AD.

Electroacupuncture for relieving itching in atopic eczema: study protocol for a multicenter, randomized, sham-controlled trial

Background

Atopic eczema (AE) is a common atopic inflammatory skin disease affecting 2.1-4.9% of the population in different countries. Pruritus, one of the most burdensome symptoms, is often underestimated for the problems it can cause, creating a vicious loop of itching, scratching, and lichenification. Therefore, further research into practical and safe treatments that relieve itchy symptoms and enhance skin protection is key to overcoming AE. Acupuncture, with or without electrical stimulation, is one of the most commonly used therapeutic measures to treat AE. This trial aimed to objectively evaluate the efficacy and safety of the electroacupuncture (EA) antipruritic technique in AE pruritus and obtain high-level clinical evidence for the popularization and application of EA for AE.

Methods and analysis

This multicenter, single-blinded, randomized controlled trial is planned to transpire from April 15, 2023, to June 30, 2025. We will recruit 132 participants with AE (44 per group). Participants will be assigned randomly to three equal-sized groups: EA, sham electroacupuncture, and sham acupuncture. Treatment will be administered three times a week during the 2-week intervention phase. The primary outcome measure is the Visual Analog Scale, with a numeric rating scale to evaluate pruritus. Secondary outcome measures include the Eczema Area and Severity Index and Dermatology Life Quality Index. Other outcome measures include physical examination, serum IgE, and safety evaluation. The number, nature, and severity of adverse events will be carefully recorded.

Trial registration

ClinicalTrials.gov, 22Y11922200. Registered 3 September 2022, https://register.clinicaltrials.gov.

Vitexin inhibits pain and itch behavior via modulating TRPV4 activity in mice

Itching and pain are distinct unpleasant sensations. The transient receptor potential cation channel subfamily V member 4 (TRPV4) pathway is regarded as a shared pathway that mediates pain and itching. Vitexin (Mujingsu, MJS), a C-glycosylflavonoid, is an effective analgesic. This study aimed to explore the antinociceptive and anti-pruritic effects of MJS and whether its effects are mediated via the TRPV4 pathway. Mice were treated with MJS (7.5 mg/kg) 0.5 h prior to the initiation of the pain or itch modeling process. The results showed that MJS suppressed pain-like behavior in hot plate, thermal infiltration, glacial acetic acid twisting, and formalin tests. Administration of MJS decreased the pruritus response induced by histamine, C48/80, chloroquine and BAM8-22 within 30 min. MJS reduced scratching bouts and lessened the wiping reaction of mice under TRPV4 activation by GSK101 (10 µg/5 μl). MJS inhibited scratching behavior in acetone-ether-water (AEW)-treated mice within 60 min. An H1 receptor antagonist-chlorpheniramine (CLP, 400 mg/kg)-and a TRPV4 antagonist-HC067047 (250 ng/kg), exhibited similar effects to those of MJS. Moreover, MJS ameliorated dry skin itch-associated cutaneous barrier disruption in mice. MJS did not inhibit the expression of TRPV4 in the dorsal root ganglion neurons at L2-L3 in AEW mice. These results indicate that the analgesic and anti-pruritic effects of MJS in acute and chronic pain and itching, as well as itching caused by TRPV4 activation, could be attributed to the TRPV4 pathway modulation.

The involvement of the primo vascular system in local enteritis and its modification by electroacupuncture

Introduction

The primo vascular system (PVS), an intensive network structure, has been claimed to be representative of the acupuncture meridian. Here, we explored the role of the PVS in local enteritis and its modification by acupuncture.

Methods

Chronic cecitis in rabbits was induced by 2,4,6-trinitro-benzene-sulfonic acid (TNBS). The PVS on the cecum was visualized with trypan blue staining, and collected with the help of microsurgical forceps under an optical stereomicroscope.

Results

The increased primo vessels (PVs) and primo nodes (PNs) of the PVS on the surface of the cecum were induced by local inflammation, which was positively correlated with the inflammatory cells in the cecal mucosa. Tandem mass tag (TMT) based proteomic analysis revealed that 110 differentiated proteins of the PVS existed between TNBS-treated and control rabbits; 65 proteins were upregulated, while 45 proteins were downregulated. These proteins were mainly enriched in inflammation- and immunity-related processes, such as inflammatory cell proliferation, antigen presentation, and cell adhesion in the proliferated PVS (data are available via ProteomeXchange with the identifiers PXD034280). Importantly, TNBS-induced cecitis, the proliferated PVS and inflammation response-related proteins (CD40, CD45, HLA-DRA1, LAMP1, JAGN1 and FGL1) in the PVS were alleviated or reversed by repetitive electroacupuncture (EA) stimulations.

Conclusion

These results suggest that the proliferated PVS and its active inclusions were related to the inflammatory process, which was modified by EA. Our study provides a new avenue for further exploration of the mechanism by which EA exerts anti-inflammatory effects.

The west meets the east - A need for a renaissance in brain, behavior, and immunity research

Psychoneuroimmunology (PNI)-the burgeoning concept in recent years, can potentially contribute to developing effective treatments for mental health disorders. Despite the advancement in the modern pharmacological approach for mental disorders, especially Western medicine attributed explicitly to interacting with a specific target has given rise to unmet needs, and treatment failure has led to the proliferation and exploration of traditional and alternative therapies. As research into these exciting under-explored traditional treatment approaches continues to evolve at an unprecedented pace, the need to gain vital insights into the potentiality and mechanism of action in neuropsychiatric disorders has resulted in the current Special Issue. This Special Issue is devoted to psychoneuroimmunology, focusing on introducing the recent advances with traditional and alternative medications in East Asia at the interface of immunology, neurosciences, molecular psychiatry and behavioural medicine neurosciences.

Acupuncture and related therapies for atopic eczema: A protocol for systematic review and network meta-analysis

BACKGROUND

Atopic eczema (AE) is a chronic relapsing dermatological disease characterized by pruritus, dryness, erythema, and lichenification. Acupuncture as an alternative treatment can relieve symptoms, reduce the recurrence, and improve the quality of life (QoL) with less adverse reactions in treating AE. This network meta-analysis (NMA) will comprehensively access the efficacy and safety of different acupuncture therapies for patients with AE, and rank the different acupuncture therapies, in order to present evidence-based medicine evidence for clinical application extensively.

METHOD AND ANALYSIS

This study will search 8 electronic databases from the establishment of the database to August 30th, 2022. The screening of literature, data extraction, and risk of bias assessment will be conducted by 2 researchers, respectively. The quality of evidence will be judged by the Grading of Recommendations Assessment, Development and Evaluation system. This NMA will be analyzed with Stata Version. 14.0 and WinBUGS Version.1.4.3.

RESULTS

This study will comprehensively access the efficacy and safety of different acupuncture therapies for patients with AE on the severity, itch intensity, emotional symptoms, QoL, and recurrence rate. Moreover, it will further identify which acupuncture therapy is the most effective.

CONCLUSION

The findings of this NMA may help patients and therapists choose the best acupuncture therapy in treating AE and furnish reliable evidence for guidelines.

REGISTRATION NUMBER

PROSPERO CRD42020203437.

Efficacy of Acupuncture for Treatment of Atopic Eczema and Chronic Eczema: A Systematic Review and Meta-analysis

Abstract is missing (Short communication)

Acupuncture attenuates comorbid anxiety- and depressive-like behaviors of atopic dermatitis through modulating neuroadaptation in the brain reward circuit in mice

Atopic dermatitis (AD) is highly comorbid with negative emotions such as anxiety and depression. Although acupuncture has demonstrated efficacy in AD, its influence on comorbid anxiety and depression remains unclear. We sought to explore the impact and mechanisms of action of acupuncture on comorbid anxiety and depression of AD. AD-like skin lesions were induced by the topical application of MC903 to the mouse cheek. Acupuncture was performed at Gok-Ji (LI11) acupoints. AD-like phenotypes were quantified by lesion scores, scratching behavior, and histopathological changes. The effects of acupuncture on comorbid anxiety and depression-like behaviors were assessed using the elevated plus-maze (EPM), open-field tests (OFT), and tail-suspension test (TST). In addition, biochemical changes in the brain reward regions were investigated by immunoblotting for the expression of tyrosine hydroxylase (TH), dopamine D1 receptor (D1R), phospho-dopamine and cAMP-regulated phosphoprotein-32 kDa (pDARPP-32), phospho-cAMP response element binding protein (pCREB), ΔFosB, and brain-derived neurotrophic factor (BDNF) in the nucleus accumbens, dorsolateral striatum, and ventral tegmental area. Acupuncture effectively improved the chronic itching and robust AD-like skin lesions with epidermal thickening. Additionally, it considerably reduced comorbid anxiety- and depression-like symptoms, as indicated by more time spent in the open arms of the EPM and in the center of the open field and less time spent immobile in the TST. Higher pCREB, ΔFosB, BDNF, and pDARPP-32 levels, and reduced TH and D1R protein expression in the brain reward regions of AD mice were reversed by acupuncture treatment. The beneficial effects of acupuncture on clinical symptoms (scratching behavior) and comorbid psychological distress in AD strongly correlated with dorsal striatal ΔFosB levels. Collectively, these data indicate that acupuncture had a significant, positive impact on comorbid anxiety- and depression-like behaviors by modulating neuroadaptation in the brain reward circuit in mice with AD, providing a novel perspective for the non-pharmacological management of psychiatric comorbidities of AD.

Treatment Options for Troublesome Itch

Itch (or pruritus) is an unpleasant sensation, inducing the desire to scratch. It is also a major and distressing symptom of many skin and systemic diseases. The involvement of histamine, which is a major itch mediator, has been extensively examined. Recent studies suggest that histamine-independent pathways may play roles in chronic itch. Therefore, antihistamines are not always effective in the treatment of patients with chronic itch. The development of biologics and κ-opioid receptor (KOR) agonists has contributed to advances in the treatment of itch; however, since biologics are expensive for patients to purchase, some patients may limit or discontinue their use of these agents. Furthermore, KOR agonists need to be prescribed with caution due to risks of side effects in the central nervous system. Janus kinase (JAK) inhibitors are sometimes associated with side effects, such as infection. In this review, we summarize antidepressants, antineuralgics, cyclosporine A, antibiotics, crotamiton, phosphodiesterase 4 inhibitor, botulinum toxin type A, herbal medicines, phototherapy, and acupuncture therapy as itch treatment options other than antihistamines, biologics, opioids, and JAK inhibitors; we also explain their underlying mechanisms of action.

Acupuncture for the Treatment of Itch: Peripheral and Central Mechanisms

Despite the widespread clinical use of acupuncture in the treatment of pruritus caused by psoriasis, urticaria, uremic, and other diseases, insights into the mechanism of action of acupuncture are still emerging. For the above reasons, a beneficial effect of acupuncture on pruritus was not recommended or reported in recent clinical practice guidelines. Acupuncture is a kind of physical stimulation, which has the characteristics of multi-channel and multi-target effects. The biomechanical stimulation signal of acupuncture needling can be transformed into bioelectric and chemical signals; interfere with kinds of cells and nerve fibers in the skin and muscle; alter signaling pathways and transcriptional activity of cells, mediators, and receptors; and result in inhibition of peripheral and central transmission of pruritus. Available mechanistic data give insights into the biological regulation potency of acupuncture for pruritus and provide a basis for more in-depth and comprehensive mechanism research.