The Hot-Water Extract of Smilacis Chinae Rhizome Suppresses 2,4-Dinitrochlorobenzene and House Dust Mite-Induced Atopic Dermatitis-Like Skin Lesions in Mice

Hydrogel-Based Treatment of House Dust Mite-Induced Atopic Dermatitis through Triple Cleaning of Mites, Bacteria, and ROS-Related Inflammation

Atopic dermatitis (AD) is a chronic and recurrent inflammatory disease caused by abnormalities in skin immunoregulation. House dust mite can directly damage the skin barrier and thus sensitize the skin, which is one of the main allergens inducing AD in humans and widely exists in daily life. Meanwhile, the accompanying bacterial infections and exposure to additional allergens exacerbate the condition by generating excessive reactive oxygen species (ROS). Herein, we have developed the CPDP hydrogel with injectable and self-healing ability to combat pathogenic microorganisms and inflammatory environments for AD therapy. In vitro experiments have affirmed the efficacy of the CPDP hydrogel in combating mites, killing bacteria, and scavenging ROS. In a mouse model closely mimicking HDM-induced AD, the CPDP hydrogel has shown superior therapeutic effects, including reducing epidermal thickness and mast cell count, increasing collagen deposition, as well as down-regulating pro-inflammatory factors.

Oral Administration of East Asian Herbal Medicine for Inflammatory Skin Lesions in Plaque Psoriasis: A Systematic Review, Meta-Analysis, and Exploration of Core Herbal Materials

Psoriasis is an inflammatory autoimmune skin disease with various clinical manifestations. The aim of this review was to systematically evaluate the efficacy and safety of oral administration of East Asian herbal medicine (EAHM) for inflammatory skin lesions in psoriasis and to explore core herbal materials for drug discovery. A comprehensive search was conducted in 10 electronic databases for randomized controlled trials from their inception until 29 July 2021. Statistical analysis was performed in R version 4.1.2 and R studio. When heterogeneity in studies was detected, the cause was identified through sensitivity analysis, meta-regression, and subgroup analysis. Methodological quality was independently assessed using the revised tool for risk of bias in randomized trials. A total of 56 trials with 4966 psoriasis patients met the selection criteria. Meta-analysis favored EAHM monotherapy on Psoriasis Area Severity Index (PASI) 70 (RR: 1.2845; 95% CI: 1.906 to 1.3858, p < 0.0001), PASI 60 (RR: 1.1923; 95% CI: 1.1134 to 1.2769, p < 0.0001), continuous PASI score (MD: −2.3386, 95% CI: −3.3068 to −1.3704, p < 0.0001), IL-17, IL-23, TNF-α, and Dermatology Life Quality Index. Patients treated with EAHM monotherapy had significantly reduced adverse events incidence rate. In addition, based on additional examination of the herb data included in this meta-analysis, 16 core materials were identified. They are utilized in close proximity to one another, and all have anti-inflammatory properties. The findings in this study support that oral EAHM monotherapy may be beneficial for inflammatory skin lesions in psoriasis. Meanwhile, the identified core materials are expected to be utilized as useful drug candidate hypotheses through follow-up studies on individual pharmacological activities and synergistic effects.

Rosa davurica Pall. improves DNCB-induced atopic dermatitis in mice and regulated TNF-Alpa/IFN-gamma-induced skin inflammatory responses in HaCaT cells

PURPOSE

Rosa davurica Pall., is mainly distributed in Korea, Japan, northeastern China, southeastern Siberia, and eastern Asia. It has been extensively used to treat various kinds of diseases by reason of the significant antioxidant, antiviral and anti-inflammatory activities. However, the pharmacological mechanism of Rosa davurica Pall. in atopic dermatitis (AD) is still ill defined and poorly understood. This study was to examine the anti-inflammatory effects and its mechanism on AD of Rosa davurica Pall. leaves (RDL).

METHODS

To evaluate the therapeutic potential of RDL against AD, we have investigated the effects of RDL on the inflammatory reactions and the productions of inflammatory chemokines and cytokines that were induced by tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ) in HaCaT cells. Futhermore, we examined the effects of RDL on the signaling pathways of mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB). For the in-vivo studies, RDL extract was topically applied to the dinitrochlorobenzene (DNCB)-induced AD mice, then its therapeutic effect was evaluated physiologically and morphologically.

RESULTS

After the stimulation of HaCaT cells with TNF-α/IFN-γ, RDL considerably reduced the release of inflammatory mediators such as nitric oxide (NO), PEG₂ and other cytokines. RDL also reduced the phosphorylations of MAPK and NF-κB in TNF-α/IFN-γ-stimulated HaCaT cells. In vivo topical application of RDL to DNCB-induced AD mice significantly reduced the dorsal skin and ear thickness, clinical dermatitis severity, and mast cells. Treatment with RDL also markedly decreased the levels of serum IgE, IL-6 and the number of WBCs in the blood.

CONCLUSION

Our studies indicate that RDL inhibits the AD-like skin lesions by modulating skin inflammation. Consequently, these results suggest that RDL may be served as a possible alternative therapeutic treatment for skin disorder such as AD.

Ethanolic Extracts of Artemisia apiacea Hance Improved Atopic Dermatitis-Like Skin Lesions In Vivo and Suppressed TNF-Alpha/IFN-Gamma⁻Induced Proinflammatory Chemokine Production In Vitro

Artemisia apiacea Hance is a traditional herbal medicine used for treating eczema and jaundice in Eastern Asia including China, Korea, and Japan. However, the biological and pharmacological actions of Artemisia apiacea Hance in atopic dermatitis (AD) are not fully understood. An ethanolic extract of Artemisia apiacea Hance (EAH) was tested in vitro and in vivo to investigate its anti-inflammatory activity and anti-atopic dermatitis effects. The results showed that EAH dose-dependence inhibited production of regulated on activation, normal T-cell expressed and secreted (RANTES), interleukin (IL)-6, IL-8, and thymus and activation-regulated chemokine (TARC). EAH inhibited the activation of p38, extracellular signal-regulated kinases (ERK), and STAT-1 and suppressed the degradation of inhibited both nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor-alpha (IκB-α) in TNF-α/IFN-γ–stimulated HaCaT cells. EAH also suppressed the translocation of inflammation transcription factors such as NF-κB p65 in TNF-α/IFN-γ–stimulated HaCaT cells. In addition, EAH reduced 2,4-dinitrochlorobenzene (DNCB)-induced ear thickness and dorsal skin thickness in a dose-dependent manner. EAH appeared to regulate chemokine formation by inhibiting activation of and ERK as well as the NK-κB pathways. Furthermore, EAH significantly improved the skin p38 conditions in a DNCB-induced AD-like mouse model.