Acupuncture Needling, Electroacupuncture, and Fire Needling
in an Imiquimod-Induced Psoriasis-Like Mouse Model

Background: Why discuss acupuncture in psoriasis?

Psoriasis is a chronic autoimmune skin disease characterized by erythematous, scaly, and thickened plaques. On the immunological level, various immune cells — such as dendritic cells, T cells, and neutrophils — release pro-inflammatory cytokines including IL-23, IL-17, IL-1β, IL-6, and IL-22, driving a persistent inflammatory cascade.

Conventional treatments include topical corticosteroids, vitamin D analogues, oral methotrexate (MTX), and biologic agents. However, a substantial proportion of patients remain dissatisfied due to limited efficacy or adverse effects. As a result, many people seek complementary and alternative therapies, among which acupuncture and related techniques are frequently used.

While clinical reports suggest that acupuncture may help improve psoriatic lesions, the comparative effectiveness of different techniques (manual needling, electroacupuncture, fire needling, etc.) and their underlying mechanisms have not been fully clarified. The animal study discussed here was designed to address this gap.

Aim of the Study

The authors compared three acupuncture-related techniques:

• Manual acupuncture needling
• Electroacupuncture
• Fire needling

in an imiquimod (IMQ)-induced psoriasis-like mouse model, and explored whether these interventions might act through immune modulation and neuro-modulation to improve psoriatic inflammation.

Study Design: IMQ-Induced Psoriasis-Like Mouse Model

Eight-week-old male BALB/c mice were used. A 2 × 2 cm area on the back was shaved, and 5% imiquimod cream (IMQ) was applied for 9 consecutive days to induce psoriasis-like skin inflammation.

Six groups (8 mice per group) were included:

• Control group: vaseline only.
• Model group: IMQ applied, no treatment.
• MTX group: IMQ + oral MTX (1 mg/kg/day from day 4).
• Acupuncture needling (AN): IMQ + manual needling at Dazhui (DU14) and right Zusanli (ST36), 8 min/day from day 4.
• Electroacupuncture (EA): IMQ + EA at DU14 and right ST36, 8 min/day from day 4, 2/100 Hz, 10 mA, with visible body shaking.
• Fire needling (FN): IMQ + fire needling at DU14 and right ST36 every other day from day 4.

Assessments included:

• Psoriasis Area and Severity Index (PASI) – erythema, scaling, and thickness scored 0–4.
• Histology (H&E) and epidermal thickness measurement.
• PCNA and CD3 immunohistochemistry for keratinocyte proliferation and T cell infiltration.
• Skin and serum cytokines: IL-17A, IL-1β, IL-22, IL-23p40.
• Neuropeptides: Neurokinin A (NKA) and Substance P (SP).

Key Findings

1. Visible and histological improvement of skin lesions

Within several days of IMQ application, mice developed psoriasis-like lesions with erythema, scaling, and thickening. From day 4 onwards, treatment with manual acupuncture, electroacupuncture, fire needling, or MTX led to gradual improvement of skin appearance: smoother back skin, less redness, and fewer scales.

Histological analysis showed pronounced acanthosis, parakeratosis, and inflammatory cell infiltration in the model group, while all treated groups exhibited thinner epidermis and reduced inflammation. Overall, the three acupuncture-related techniques achieved improvements comparable to MTX in many of the measured parameters, although MTX produced the greatest reduction in epidermal thickness.

2. Reduced keratinocyte proliferation and T cell infiltration

PCNA staining revealed markedly increased keratinocyte proliferation in the model group. In contrast, PCNA-positive cells were significantly reduced in the manual acupuncture, electroacupuncture, fire needling, and MTX groups.

CD3 immunostaining demonstrated abundant T cell infiltration in the model group. All three acupuncture-related techniques, as well as MTX, reduced CD3⁺ T cell infiltration in the skin, indicating a decrease in local immune activation.

3. Modulation of key inflammatory cytokines (IL-23 / IL-17 axis)

In line with current understanding of psoriasis pathogenesis, the IMQ model group showed elevated levels of IL-17A, IL-22, IL-1β, and IL-23p40 in skin lesions. Treatment with manual acupuncture, electroacupuncture, fire needling, or MTX significantly reduced IL-17A, IL-1β, and IL-23p40 in the skin.

In serum, the model group also showed increased IL-23p40 and IL-22. Fire needling reduced serum IL-23p40, and all acupuncture-related techniques decreased serum IL-22, suggesting that acupuncture may influence not only local skin inflammation but also systemic inflammatory status to some extent.

Importantly, electroacupuncture produced a more pronounced reduction of IL-17A and IL-1β compared with manual acupuncture and fire needling, highlighting a potentially stronger anti-inflammatory effect on the IL-23 / IL-17 axis.

4. Neuropeptides and neuromodulation: a possible added value of electroacupuncture

The study also evaluated neuropeptides related to neurogenic inflammation — Substance P (SP) and Neurokinin A (NKA). Both were elevated in IMQ-induced lesions. Manual acupuncture and electroacupuncture reduced NKA levels, and NKA expression positively correlated with IL-1β and IL-23p40, suggesting a link between neuropeptide activity and local skin inflammation.

These findings support the idea that electroacupuncture may exert its effects not only through immune modulation but also via neuromodulation, by dampening local neuropeptide signaling and thereby reducing inflammatory responses.

Interpretation and Clinical Perspective

Taken together, this animal study suggests that manual acupuncture, electroacupuncture, and fire needling can all ameliorate IMQ-induced psoriasis-like skin lesions in mice, by reducing epidermal hyperplasia, T cell infiltration, and key inflammatory cytokines.

Among the three, electroacupuncture stood out with the most pronounced reductions in IL-17A, IL-1β, and NKA, pointing toward a combined immune-regulating and neuro-modulating action.

It is important to emphasize that this is an animal model, not a clinical trial in humans. The results cannot be directly extrapolated to individual patients. However, they offer mechanistic insights that may help us understand how acupuncture-related techniques could be integrated as complementary options in the broader management of psoriasis and other inflammatory skin conditions.

For clinicians and researchers, these data encourage further exploration of acupuncture as a potential adjunctive therapy, particularly approaches like electroacupuncture that may engage both immune and neural pathways.

Take-Home Message

In an IMQ-induced psoriasis-like murine model, manual acupuncture, electroacupuncture, and fire needling all improved skin lesions and reduced inflammatory responses. Electroacupuncture appeared particularly effective, possibly because it modulates both the IL-23 / IL-17 immune axis and local neuropeptides such as Neurokinin A, offering a combined anti-inflammatory and neuromodulatory effect.

Reference

Wang Y, Fu Y, Zhang L, et al. Acupuncture Needling, Electroacupuncture, and Fire Needling Improve Imiquimod-Induced Psoriasis-Like Skin Lesions through Reducing Local Inflammatory Responses. Evidence-Based Complementary and Alternative Medicine. 2019;2019:4706865. Available via PubMed Central: https://pmc.ncbi.nlm.nih.gov/articles/PMC6699296/