[Effect of moxibustion on skin lesions and immune inflammatory response in psoriasis mice]

To observe the effect of moxibustion on skin lesions and immune inflammatory response in psoriasis mice, and to explore the possible mechanism of moxibustion for psoriasis.

A total of 32 male BALB/c mice were randomly divided into a normal group, a model group, a moxibustion group and a medication group, 8 mice in each group. Psoriasis model was induced by applying 5% imiquimod cream on the back for 7 days in the model group, the moxibustion group and the medication group. At the same time of model establishment, the moxibustion group was treated with suspension moxibustion on skin lesions on the back, 20 min each time, once a day; the medication group was treated with 1 mg/kg methotrexate tablet solution by gavage, once a day. Both groups were intervened for 7 days. The daily changes of skin lesions were observed, and the psoriasis area and severity index (PASI) score was evaluated; the histopathological changes of skin lesions were observed by HE staining; the positive expression of proliferating cell nuclear antigen (PCNA) and T lymphocyte surface marker CD₃ were detected by immunohistochemistry; the expression level of serum interleukin (IL) -17A was detected by ELISA, and the relative expressions of tumor necrosis factor-α (TNF-α), IL-1β and IL-6 mRNA in skin lesions were detected by real-time PCR.

The increased and hypertrophy scale, dry skin, red and swollen epidermis and obvious infiltration were observed in the model group, and each score and total score of PASI were higher than those in the normal group (P<0.01). The scale score, infiltration score, and total score of PASI in the moxibustion group were lower than those in the model group (P<0.01); the infiltration score and total score of PASI in the medication group were lower than those in the model group (P<0.01, P<0.05). The inflammatory cell infiltration in the model group was obvious, and the thickness of epidermal layer was increased compared with that in the normal group (P<0.01); the inflammatory cell infiltration and Munro micro abscess were decreased in the moxibustion group and the medication group, and the thickness of epidermal layer was decreased compared with that in the model group (P<0.01). Compared with the normal group, the positive cell number of PCNA and T was increased (P<0.01), and the body mass was decreased, and the spleen index was increased (P<0.01), and the expression of serum IL-17A and the relative expression of TNF-α, IL-1β and IL-6 mRNA in the skin lesions was increased in the model group (P<0.01). Compared with the model group, the positive cell number of PCNA and T was reduced (P<0.01), and the spleen index and the relative expression of TNF-α, IL-1β and IL-6 mRNA were reduced (P<0.01) in the moxibustion group and the medication group; the body mass of mice in the moxibustion group was higher than that in the model group (P<0.01); the content of serum IL-17A in the medication group was lower than that in the model group (P<0.01); the relative expression of TNF-α, IL-1β mRNA in the moxibustion group was higher than that in the medication group (P<0.01).

Moxibustion could effectively improve the scale and infiltration of skin lesions in psoriasis mice. Its mechanism may be related to inhibiting inflammatory response and regulating immunity.