Assessment of the anti-psoriasis effect of Scrophularia deserti methanolic extract in mice model

Abstract

Psoriasis is an underestimated chronic and autoimmune skin disorder. Topical chemical agents are applied for psoriasis control and treatment, notwithstanding their subordinate efficiency or unsuccessful activities. As an alternative, herbal medicine can also be used in its treatment. The aim of the present study was performed to assess the anti-psoriasis effect of Scrophularia deserti in mice model. Materials and methods: S. deserti was purchased and used for methanolic extraction. Extract DPPH radical scavenging activity, polyphenol and flavonoid contents were examined. Sixty male mice were purchased, and psoriasis was induced using 10 days of topical administration of Imiquimod (62.5 mg). Mice were classified into 6 groups: non-psoriasis control (only received distilled water), psoriasis control (only received topical Imiquimod), two S. deserti treatments (topical 300 and 500 mg/kg), topical Betamethasone, and topical α-pinene 9  %. Cytokine distribution and histopathological properties were also determined. Results: the value at which the S. deserti methanolic extract scavenges 50 % of free radicals (IC50) was 602.71±15.33 µg/mL. The total S. deserti methanolic extract flavonoid and polyphenol contents were 16.85±1.12 mg QE/g and 58.47±3.25 mg GAE/g, respectively. IL-22, TNF-α, and IL-17A concentrations increased after psoriasis induction compared to the control group (P <0.05). Mice treated with Betamethasone harboured the lowest concentrations of IL-22, TNF-α, and IL-17A (P <0.05). Conclusions: Mice treated with S. deserti methanolic extract (500 mg/kg) also harboured significantly lower IL-22, TNF-α, and IL-17A (P <0.05) compared to α-pinene and S. deserti methanolic extract (300 mg/kg). Mice of the psoriasis control group showed significant epidermis hyperkeratosis, acanthosis, and crust with plentiful inflammatory cells. At the same time, mice treated with S. deserti methanolic extract (500 mg/kg) showed significant recovered tissue with normal skin epidermis and dermis, sebaceous glands, and follicles of the hair, besides the lowest rate of inflammatory reactions. Findings showed that the S. deserti methanolic extract (500 mg/kg) can efficiently be used as a practical substitute for psoriasis treatment. However, some supplementary research should be performed