Psoriasis is recognized as an autoimmune and inflammatory dermatosis, which is estimated to affect 2-3% of the population worldwide. 18β-Glycyrrhetinic acid (GA), one of the main ingredients of Licorice (Glycyrrhiza glabra L.), has been shown to have numerous pharmacological effects such as antioxidative, antitumor, and anti-inflammatory activities. However, it remains to be explored whether GA has antipsoriatic effect on psoriasis. In this study, we evaluated the protective effect of GA on psoriasis and its mechanisms of action in imiquimod-induced psoriasis-like mouse model. Results indicated that GA dramatically improved psoriatic lesions and reduced psoriasis area and severity index scores. GA also suppressed the mRNA levels of IL-6, TNF-α, IL-17, IL-23, and IL-1β in the skin and increased the proportion of CD4+ Foxp3+ regulatory T cells (Tregs) in both lymph nodes and spleens. Its anti-inflammatory and immunomodulatory activities may be related to its suppression of the STAT3 and mTOR signaling. In conclusion, GA ameliorated the symptoms of psoriasis, at least in part, through inhibition of inflammatory cytokines and STAT3/mTOR signaling and activation of Tregs in both lymph nodes and spleens. These effects are expected to be beneficial in the treatment and prevention of psoriasis.

中文翻译：

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18β-甘草次酸通过抑制 mTOR/STAT3 信号传导对小鼠咪喹莫特诱导的银屑病具有保护作用。


牛皮癣被认为是一种自身免疫性炎症性皮肤病，估计影响全球 2-3% 的人口。 18 β-甘草次酸 (GA) 是甘草 (Glycyrriza glabra L.) 的主要成分之一，已被证明具有多种药理作用，如抗氧化、抗肿瘤和抗炎活性。然而，GA对银屑病是否具有抗银屑病作用仍有待探讨。在本研究中，我们在咪喹莫特诱导的银屑病样小鼠模型中评估了 GA 对银屑病的保护作用及其作用机制。结果表明，GA 显着改善银屑病皮损并降低银屑病面积和严重程度指数评分。 GA 还抑制皮肤中 IL-6、TNF- α 、IL-17、IL-23 和 IL- 1β的 mRNA 水平，并增加淋巴结和脾脏中 CD4+ Foxp3+ 调节性 T 细胞 (Treg) 的比例。其抗炎和免疫调节活性可能与其抑制 STAT3 和 mTOR 信号传导有关。总之，GA 至少部分地通过抑制炎症细胞因子和 STAT3/mTOR 信号传导以及激活淋巴结和脾脏中的 Tregs 来改善银屑病的症状。预计这些作用将有益于牛皮癣的治疗和预防。