Department of Histology and Embryology，School of Basic Medical Sciences, Southern Medical University, Guangzhou, China; GDMPA Key Laboratory of Key Technologies for Cosmetics Safety and Efficacy Evaluation, NMPA Key Laboratory for Safety Evaluation of Cosmetics, Southern Medical University, Guangzhou, China.
Guangzhou Dublin International College of Life Sciences and Technology, South China Agricultural University, Guangzhou, China.
Int Immunopharmacol. 2024 Sep 30;139:112706. doi: 10.1016/j.intimp.2024.112706. Epub 2024 Jul 19.
Emu oil is the oil extracted from the body fat of the Australian bird emu. Although previous studies have reported that emu oil has anti-inflammatory effects, the effect and mechanism of emu oil on the treatment of atopic dermatitis have not been reported. Here, 2, 4-dinitrofluorobenzene was used to induce atopic dermatitis-like appearance on the back skin of C57BL/6 mice. And then, the effect of emu oil in the atopic dermatitis treatment was evaluated. We found that emu oil reduced the transdermal water loss in the atopic dermatitis model. Additionally, the epidermal thickness treated with emu oil was significantly thinner. The number of mast cells and inflammatory cells were significantly decreased. The thymic stromal lymphopoietin (TSLP), which is secreted by keratinocyte, was decreased significantly after treatment. Moreover, the serum levels of cytokines TSLP, interleukin-4, interleukin-13, and immunoglobulin (Ig) E were decreased after emu oil treatment. Surprisingly, we found that the high level of Cdc42 expression in the atopic dermatitis, which was decreased after emu oil treatment. To detect the role of Cdc42 in atopic dermatitis, we constructed atopic dermatitis model in mice with sustained activation of Cdc42 signaling. Furthermore, we have confirmed that emu oil demonstrates anti-inflammatory effects in atopic dermatitis by inhibiting the expression of Cdc42 signaling in keratinocytes. In conclusion, we discovered a new role of Cdc42 in the development of atopic dermatitis, which mediated the therapeutic effect of emu oil on atopic dermatitis.
鸸鹋油是从澳大利亚鸸鹋鸟的体脂肪中提取的油。尽管先前的研究报道鸸鹋油具有抗炎作用，但鸸鹋油治疗特应性皮炎的效果和机制尚未报道。在这里，2,4-二硝基氟苯被用于诱导 C57BL/6 小鼠背部皮肤出现特应性皮炎样外观。然后，评估了鸸鹋油在特应性皮炎治疗中的效果。我们发现鸸鹋油减少了特应性皮炎模型中的经皮水分丢失。此外，用鸸鹋油处理的表皮厚度明显变薄。肥大细胞和炎症细胞的数量明显减少。角质形成细胞分泌的胸腺基质淋巴细胞生成素（TSLP）在治疗后显著减少。此外，鸸鹋油治疗后血清中 TSLP、白细胞介素-4、白细胞介素-13 和免疫球蛋白（Ig）E 的水平降低。令人惊讶的是，我们发现特应性皮炎中 Cdc42 表达水平升高，而鸸鹋油治疗后其表达水平降低。为了检测 Cdc42 在特应性皮炎中的作用，我们构建了 Cdc42 信号持续激活的特应性皮炎小鼠模型。此外，我们已经证实，鸸鹋油通过抑制角质形成细胞中 Cdc42 信号的表达，在特应性皮炎中发挥抗炎作用。总之，我们发现 Cdc42 在特应性皮炎的发展中具有新的作用，它介导了鸸鹋油对特应性皮炎的治疗作用。
