College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China.
College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China; Center of Research and Innovation of Chinese Traditional Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China.
J Ethnopharmacol. 2022 Nov 15;298:115543. doi: 10.1016/j.jep.2022.115543. Epub 2022 Jul 21.
In treating atopic dermatitis, multi-mode management is adopted, including trying to avoid the allergens, controlling and preventing secondary infections, and using drugs to control itching. At present, most of the commonly used anti-pruritic drugs in the clinic are single-target and lead to serious side effects. Many studies have shown that a variety of traditional Chinese medicines have significant anti-inflammatory and anti-pruritic effects, and have the characteristics of multiple components, multiple targets, and multiple effects.
The study aimed to explore the anti-inflammatory and anti-pruritic effects of the Chi-Huang Solution in a murine model of Allergic contact dermatitis (ACD). This study considers the effectiveness of the Chi-Huang Solution for external use on skin to provide an experimental basis for the clinical development and application of Chinese medicine and related preparations for Canine atopic dermatitis (CAD).
Forty-two male SPF C57BL/6 mice were randomly divided into control group (n = 6), ACD model group (n = 6), HAC control group (n = 6), and 4 Chi-Huang Solution groups (n = 6 in each group). With SADBE induce the murine model of ACD chronic pruritus, and initially evaluate whether the model is successful by counting scratching behavior, measuring the skin fold thickness and skin lesion score within 1 h. After treating the ACD model mice with deionized water, HAC, 1CH, 2CH, 3CH, and 4CH for 7 days, behavioral changes were used to evaluate the anti-pruritic effect. The skin fold thickness, skin lesion score, and spleen index were used to evaluate the anti-inflammatory effect of the Chi-Huang Solution. H.E. staining was used for the epidermal thickness measurement and pathological evaluation. RT-qPCR was used to analyze the mRNA expression of related inflammatory factors such as IL-1β, TNF-α, IL-33, IL-4, IL-17A, CXCL10, and its receptor CXCR3 in the skin of the lesion site, as well as to detect the mRNA expression of pruritus-related genes such as TRPV1, TRPA1, and GRP in DRG.
After the treatment of low-dose (0.1 g/mL) and medium-dose (0.2 g/mL) Chi-Huang Solution, the scratching times both decreased significantly (P < 0.05), meanwhile the medium-dose Chi-Huang Solution had an obvious effect on reducing scratches/scab score (P < 0.05). Moreover, no matter what dose it takes, all Chi-Huang Solution can alleviate the epidermal thickening (P < 0.05) and the infiltration of mast cells in the ACD murine model of ACD. It is worth mentioning that the count of mast cells in the dermis was significantly down-regulated after the treatment of medium-dose Chi-Huang Solution (P < 0.005). Furthermore, Chi-Huang Solution can significantly down-regulate the mRNA expression of related inflammatory factors in the skin, and reduce the mRNA expression of pruritus-related genes, such as TRPA1, TRPV1, and GRP in the spinal cord.
The results indicated that Chi-Huang Solution for external use exhibits significant anti-inflammatory and anti-pruritic effects on SADBE-induced ACD chronic pruritus murine models. Chi-Huang Solution might emerge as an effective drug for the treatment of CAD and high-dose Chi-Huang Solution (0.4 g/ml) has better comprehensive effects.
在治疗特应性皮炎方面，采用多模式管理，包括尽量避免过敏原、控制和预防继发感染，以及使用药物来控制瘙痒。目前，临床上常用的大多数止痒药物都是单一靶点的，会导致严重的副作用。许多研究表明，多种中药具有显著的抗炎和止痒作用，且具有多成分、多靶点、多效性的特点。
本研究旨在探讨中药复方止痒膏（Chi-Huang Solution）在变应性接触性皮炎（ACD）小鼠模型中的抗炎止痒作用。本研究考虑了 Chi-Huang Solution 外用治疗皮肤的有效性，为中药及相关制剂治疗犬特应性皮炎（CAD）的临床开发和应用提供了实验依据。
42 只雄性 SPF C57BL/6 小鼠随机分为对照组（n = 6）、ACD 模型组（n = 6）、HAC 对照组（n = 6）和 4 个 Chi-Huang Solution 组（每组 n = 6）。采用 SADBE 诱导 ACD 慢性瘙痒的小鼠模型，通过记录搔抓行为、测量 1 h 内皮肤褶皱厚度和皮肤损伤评分，初步评估模型是否成功。在使用去离子水、HAC、1CH、2CH、3CH 和 4CH 治疗 ACD 模型小鼠 7 天后，通过行为变化评估止痒效果。测量皮肤褶皱厚度、皮肤损伤评分和脾指数，评估 Chi-Huang Solution 的抗炎作用。H.E.染色用于测量表皮厚度和进行病理评估。采用 RT-qPCR 分析病变部位皮肤中相关炎症因子（如 IL-1β、TNF-α、IL-33、IL-4、IL-17A、CXCL10 及其受体 CXCR3）的 mRNA 表达，并检测瘙痒相关基因（如 TRPV1、TRPA1 和 GRP）在 DRG 中的 mRNA 表达。
低剂量（0.1 g/mL）和中剂量（0.2 g/mL）Chi-Huang Solution 治疗后，搔抓次数均明显减少（P < 0.05），同时中剂量 Chi-Huang Solution 对减少搔抓/结痂评分有明显效果（P < 0.05）。此外，无论剂量如何，Chi-Huang Solution 均能减轻 ACD 小鼠模型的表皮增厚（P < 0.05）和肥大细胞浸润。值得注意的是，中剂量 Chi-Huang Solution 治疗后真皮层的肥大细胞计数明显下调（P < 0.005）。此外，Chi-Huang Solution 能显著下调皮肤中相关炎症因子的 mRNA 表达，并降低脊髓中瘙痒相关基因（如 TRPA1、TRPV1 和 GRP）的 mRNA 表达。
结果表明，Chi-Huang Solution 对外用治疗 SADBE 诱导的 ACD 慢性瘙痒具有显著的抗炎和止痒作用。Chi-Huang Solution 可能成为治疗 CAD 的有效药物，高剂量 Chi-Huang Solution（0.4 g/ml）具有更好的综合效果。
