Department of Dermatology, Far Eastern Memorial Hospital, New Taipei City, 22060, Taiwan; School of Medicine, Wayne State University, Detroit, 48201, USA.
Department of Medicine, Mackay Medical College, New Taipei City, 25245, Taiwan; Department of Dermatology, MacKay Memorial Hospital, Taipei, 10491, Taiwan; Mackay Junior College of Medicine, Nursing, and Management, New Taipei City, 11260, Taiwan.
J Ethnopharmacol. 2020 Dec 5;263:113037. doi: 10.1016/j.jep.2020.113037. Epub 2020 May 30.
Numerous epidemiological and clinical studies have demonstrated the protective role of dietary isoflavones against development of several chronic diseases. ISO-1, one fraction of isoflavone powders derived from soybean cake, is reported to attenuate inflammation and photodamage.
Contact dermatitis is a common inflammatory skin disease, which accounts for most occupational skin disorders. Instead of oral administration, we aimed to explore the effects of topical ISO-1 application on contact dermatitis by using 2,4-dinitrochlorobenzene (DNCB)-stimulated HaCaT keratinocytes and DNCB-induced mouse dermatitis as models.
In the in vitro study, we first evaluated the biologic effects of DNCB on HaCaT keratinocytes. HaCaT keratinocytes were treated with 2,4-dinitrochlorobenzene (DNCB), and cell viability was measured by MTT assay. Then, we detect the prominent induction of IL-8 mRNA expression after DNCB and ISO-1 treatment by reverse transcription polymerase chain reaction (RT-PCR), and release of IL-8 from HaCaT keratinocytes was measured by ELISA assay. HaCaT keratinocytes were pretreated with ISO-1 and then treated with DNCB, phosphorylation of JNK, p38, ERK and IκBα was analyzed by western blot. In the in vivo study, the hairless mice were used for an induced contact dermatitis model. The surface changes in the dorsal skin after DNCB and ISO-1 treatment were recorded using photography, and TEWL, erythema were measured using an MPA-580 cutometer. Blood was also collected from mice for measurement of white blood cell counts.
Results showed ISO-1 inhibited DNCB-induced IL-8 production and also suppressed DNCB-induced phosphorylation of JNK and p38, and IκBα in HaCaT. In the animal model of DNCB-induced contact dermatitis, topical ISO-1 treatment significantly decreased DNCB-induced erythema and transepidermal water loss (TEWL) in mouse skin. ISO-1 also reduced DNCB-induced skin thickening and increase of white blood cell count.
ISO-1 is promising for improvement of DNCB-induced inflammation and skin barrier impairment, suggesting the potential application of topical ISO-1 for inflammatory dermatoses.
大量流行病学和临床研究表明，膳食异黄酮对多种慢性疾病的发展具有保护作用。异黄酮粉末的一个成分 ISO-1 是从大豆饼中提取的，据报道，它可以减轻炎症和光损伤。
接触性皮炎是一种常见的炎症性皮肤病，占大多数职业性皮肤病。我们的目标是通过使用 2,4-二硝基氯苯（DNCB）刺激的 HaCaT 角质形成细胞和 DNCB 诱导的小鼠皮炎模型，探索局部应用 ISO-1 对接触性皮炎的影响，而不是口服给药。
在体外研究中，我们首先评估 DNCB 对 HaCaT 角质形成细胞的生物学效应。用 2,4-二硝基氯苯（DNCB）处理 HaCaT 角质形成细胞，通过 MTT 测定法测量细胞活力。然后，通过逆转录聚合酶链反应（RT-PCR）检测 DNCB 和 ISO-1 处理后 IL-8mRNA 表达的显著诱导，并通过 ELISA 测定法检测 HaCaT 角质形成细胞中 IL-8 的释放。用 ISO-1 预处理 HaCaT 角质形成细胞，然后用 DNCB 处理，通过 Western blot 分析 JNK、p38、ERK 和 IκBα 的磷酸化。在体内研究中，使用无毛小鼠进行诱导性接触性皮炎模型。用摄影术记录 DNCB 和 ISO-1 处理后背部皮肤的表面变化，用 MPA-580 皮肤角质层测量仪测量 TEWL 和红斑。还从小鼠采集血液用于测量白细胞计数。
结果表明，ISO-1 抑制 DNCB 诱导的 IL-8 产生，并抑制 DNCB 诱导的 HaCaT 中 JNK 和 p38 的磷酸化以及 IκBα。在 DNCB 诱导的接触性皮炎动物模型中，局部应用 ISO-1 可显著降低 DNCB 诱导的小鼠皮肤红斑和经表皮水分丢失（TEWL）。ISO-1 还降低了 DNCB 诱导的皮肤增厚和白细胞计数增加。
ISO-1 有望改善 DNCB 诱导的炎症和皮肤屏障损伤，提示局部应用 ISO-1 可能用于炎症性皮肤病。
