背景:铁皮石斛KimuraetMigo作为一种有价值的中药,在中国已经使用了2000多年。其主要活性成分,多糖(DOP),据报道具有各种药理作用,包括消炎药,抗氧化和缓解AD的作用。然而,其在AD中的治疗作用的确切机制尚不清楚.
目的:本研究旨在评估DOP的功效并阐明其改善DNFB诱导的AD的复杂机制。
方法:用DNFB致敏小鼠并用DOP施用处理14天。使用皮炎评分评估治疗效果,耳朵厚度和刮伤频率。表皮厚度,用H&E检测肥大细胞和CD4+T细胞浸润,分别进行甲苯胺蓝染色和免疫荧光染色。血清组胺(HIS),免疫球蛋白E(IgE),胸腺基质淋巴细胞生成素(TSLP),皮肤SOD,MDA,GHS,CAT,炎性细胞因子(TNF-α,IFN-γ,IL-1β,IL-4,IL-5,IL-13)和趋化因子(MIP-α,MDC,通过ELISA和免疫组织化学对MCP-1)水平进行定量。此外,进行qPCR和Western印迹分析以评估与MAPK/NF-κB/STAT3信号通路相关的基因和蛋白表达。
结果:结果表明,DOP通过多种途径有效减轻小鼠的AD样皮肤损伤。它减少了表皮厚度,AD小鼠的耳朵厚度和刮伤频率。此外,DOP通过降低炎症因子水平减轻炎症反应,以及降低血清IgE水平,HIS,和TSLP。此外,DOP抑制肥大细胞和CD4+T细胞的浸润,抑制皮肤趋化因子如MDC的表达,MCP-1和MIP-α,和增强AD小鼠中聚丝蛋白的含量。此外,DOP显著提高了抗氧化能力,以及显著降低JAK1、STAT3、NF-κBp65、IκBα的表达,ERK1/2和p38蛋白和磷酸化蛋白,如p-JAK1,p-STAT3,p-NF-κBp65,p-IκBα,p-ERK1/2和p-p38。
结论:这些发现表明DOP具有显著的抗AD活性,主要通过减少炎症反应,提高抗氧化能力,修复皮肤屏障,下调MAPK/NF-κB/STAT3信号通路中的关键基因和蛋白,这项研究可能为开发用于治疗AD的创新疗法提供有价值的见解。
BACKGROUND: Dendrobium officinale Kimura et Migo as a valuable Chinese medicine has been used in China for more than 2000 years. Its main active components, polysaccharide (DOP), has been reported to have various pharmacological effects, including anti-inflammatory, antioxidant and alleviating AD effects. However, the precise mechanism underlying its therapeutic effect in AD remains largely unclear.
OBJECTIVE: The present study sought to assess the efficacy of DOP and elucidate its intricate mechanisms in ameliorating DNFB-induced AD.
METHODS: Mice were sensitized with DNFB and treated with DOP application for 14 days. Treatment effects were assessed using dermatitis scores, ear thickness and scratching frequency. Epidermal thickness, mast cells and CD4+ T cells infiltration were detected by using H&E, toluidine blue staining and immunofluorescence staining respectively. Serum histamine (HIS), immunoglobulin E (IgE), thymic stromal lymphopoietin (TSLP), skin SOD, MDA, GHS, CAT, inflammatory cytokines (TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-13) and chemokine (MIP-α, MDC, MCP-1) levels were quantify by ELISA and immunohistochemistry. Additionally, qPCR and Western blot analyses were performed to assess genes and proteins expression associated with MAPK/NF-κB/STAT3 signaling pathway.
RESULTS: The results indicated that DOP effectively mitigated AD-like skin lesions in mice through multiple pathways. It reduced epidermal thickness, ear thickness and scratching frequency in AD mice. Additionally, DOP mitigated inflammatory responses by decreasing the levels of inflammatory factors, as well as reducing serum levels of IgE, HIS, and TSLP. Moreover, DOP inhibited infiltration of mast cells and CD4+ T cells, suppressed the expression of skin chemokines such as MDC, MCP-1, and MIP-α, and enhanced filaggrin content in AD mice. Furthermore, DOP significantly boosted antioxidant capacity, as well as significantly reduced the expression of JAK1, STAT3, NF-κB p65, IκBα, ERK1/2, and p38 proteins and phosphorylated proteins such as p-JAK1, p-STAT3, p-NF-κB p65, p-IκBα, p-ERK1/2, and p-p38.
CONCLUSIONS: These findings suggested that DOP has significant anti-AD activity, primarily through reducing inflammatory responses, improving antioxidant capacity, repairing the skin barrier, and down-regulating key genes and proteins in MAPK/NF-κB/STAT3 signaling pathway, and that this study may provide valuable insights into the development of innovative therapies for the treatment of AD.