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International Journal of Molecular... Aug 2023In dermatological research, 2,4-dinitrochlorbenzene (DNCB)-induced atopic dermatitis (AD) is a standard model as it displays many disease-associated characteristics of...
In dermatological research, 2,4-dinitrochlorbenzene (DNCB)-induced atopic dermatitis (AD) is a standard model as it displays many disease-associated characteristics of human AD. However, the reproducibility of the model is challenging due to the lack of information regarding the methodology and the description of the phenotype and endotype of the mimicked disease. In this study, a DNCB-induced mouse model was established with a detailed procedure description and classification of the AD human-like skin type. The disease was induced with 1% DNCB in the sensitization phase and repeated applications of 0.3% and 0.5% DNCB in the challenging phase which led to a mild phenotype of AD eczema. Pathophysiological changes of the dorsal skin were measured: thickening of the epidermis and dermis, altered skin barrier proteins, increased TH1 and TH2 cytokine expression, a shift in polyunsaturated fatty acids, increased pro-resolving and inflammatory mediator formation, and dysregulated inflammation-associated gene expression. A link to type I allergy reactions was evaluated by increased mast cell infiltration into the skin accompanied by elevated IgE and histamine levels in plasma. As expected for mild AD, no systemic inflammation was observed. In conclusion, this experimental setup demonstrates many features of a mild human-like extrinsic AD in murine skin.
Topics: Humans; Animals; Mice; Dermatitis, Atopic; Dinitrochlorobenzene; Reproducibility of Results; Immunoglobulin E; Skin; Cytokines; Inflammation; Mice, Inbred BALB C; Disease Models, Animal
PubMed: 37569701
DOI: 10.3390/ijms241512325 -
Journal of Ethnopharmacology Sep 2023The main clinical manifestations of eczema include itching, erythema, swelling and pain. Currently, allergies and TH1/TH2 cytokine imbalances are significant causes of...
ETHNOPHARMACOLOGICAL RELEVANCE
The main clinical manifestations of eczema include itching, erythema, swelling and pain. Currently, allergies and TH1/TH2 cytokine imbalances are significant causes of eczema. TCM believes that eczema is mainly caused by incongruity between dry and wet. Wenguanmu ointment is a classic Mongolian medicine, which mainly composed of Xanthoceras sorbifolia Bunge, Coptis chinensis Franch and Bezoar. These ingredients can clear heat and dampness, dispel wind and dehumidification, anti-inflammatoryad analgesic. In this study, it was found that Wenguanmu ointment can treat eczema with anti-inflammatory, analgesic and antipruritic.
AIM OF THE STUDY
In this study, the content of main components in Wenguanmu ointment was tested. Moreover, the therapeutic effect and mechanism of Wenguanmu ointment on eczema model mice were studied.
MATERIALS AND METHODS
Kunming mice (25 ± 2 g) were randomly divided into 6 groups: Control group; Model group; Vehicle group; Wenguanmu ointment group; Compound dexamethasone acetate cream group; Chushizhiyang ointment group. The eczema mouse model was established by DNCB. HPLC and TLC tests were used to determine the content of the main components in Wenguanmu ointment. HE staining was used to assess skin damage in mice. In order to detect the anti-inflammatory effect of Wenguanmu ointment on eczema, The levels of IgE, TNF-α, IFN-γ, COX-2 and IL-4 in serum was measured by ELISA. Genecards and Online Mendelian Inheritance in Man databases were used to analyze potential target gene predictions, and it was speculated that Wenguanmu ointment was associated with NF-κB signaling pathway and chemokine signaling pathway. To detect this inference, RT-qPCR and western blotting were used to detect protein and mRNA levels of CKLF-1, IκB-α, and NF-κB.
RESULTS
Wenguanmu ointment can repress the symptoms of eczema caused by 2, 4-dinitrochlorobenzene, and inhibit the level of serum immunoglobulin E. Simultaneously it restrain the elevation of miscellaneous pro-inflammatory cytokines and chemokines, as well as reducing the expression of CKLF-1 and NF-κB protein in the nucleus, and increasing the protein expression of IκB to improve eczema.
CONCLUSIONS
The ameliorating effect of Wenguanmu ointment on eczema lesions can play a importment role by inhibiting the CKLF-1/NF-κB pathway.
Topics: Mice; Animals; NF-kappa B; Medicine, Mongolian Traditional; Ointments; Cytokines; Inflammation; Eczema; Anti-Inflammatory Agents
PubMed: 37116728
DOI: 10.1016/j.jep.2023.116549 -
Biomedicine & Pharmacotherapy =... Dec 2023The purpose of this study was to investigate the mechanism through which rosemary essential oil treats atopic dermatitis.
OBJECTIVE
The purpose of this study was to investigate the mechanism through which rosemary essential oil treats atopic dermatitis.
METHODS
A dinitrochlorobenzene (DNCB)-induced atopic dermatitis mouse model was established and treated with low (1%), medium (2%), and high (4%) doses of Rosmarinus officinalis essential oil (EORO). Serum levels of interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-α) in each group were determined using enzyme-linked immunosorbent assay (ELISA). Skin tissues were stained with hematoxylin-eosin and toluidine blue. We used network pharmacology and molecular docking techniques to verify the biological activity of essential proteins and their corresponding compounds in the pathway. Gas chromatography-mass spectrometry (GC-MS) was used for metabolomics analysis and multivariate statistical analysis of mouse serum to screen differential metabolites and metabolic pathway analysis. Protein expression of p-JAK1, CD4+ cells, and IL-4 in the skin tissue was detected by immunohistochemistry analysis. Protein levels of STAT3, p-STAT3, P65, and p-P65 in damaged skin tissues were detected using western blotting.
RESULT
The skin of mice in the model group showed different degrees of erythema, dryness, scratches, epidermal erosion and shedding, and crusting. After treatment, the serum levels of IL-6 and TNF-α in EORO group were significantly decreased, and the expression of p-JAK1,CD4 + cells, IL-4, p-P65 / P65 and p-STAT3 / STAT3 proteins in skin tissues were decreased.
CONCLUSION
EORO can effectively improve DNCB-induced AD-like skin lesions in mice by regulating the JAK/STAT/NF-κB signaling pathway, thereby reducing the production of downstream arachidonic acid metabolites, inhibiting skin inflammation, and restoring epidermal barrier function.
Topics: Animals; Mice; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Interleukin-4; Interleukin-6; Mice, Inbred BALB C; Molecular Docking Simulation; NF-kappa B; Oils, Volatile; Rosmarinus; Signal Transduction; Skin; Tumor Necrosis Factor-alpha
PubMed: 37879216
DOI: 10.1016/j.biopha.2023.115727 -
Frontiers in Immunology 2023Atopic dermatitis (AD) is one of the most common inflammatory skin diseases with complex pathogenesis involving epidermal barrier dysfunction, skin microbiome...
Atopic dermatitis (AD) is one of the most common inflammatory skin diseases with complex pathogenesis involving epidermal barrier dysfunction, skin microbiome abnormalities and type-2-skewed immune dysregulation. Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that plays critical roles in various biological processes. However, the role of STAT3 in epidermal keratinocytes in AD remains unclear. In this study, we generated an epidermal keratinocyte-specific -deficient mouse strain (termed cKO mice). After topical 2,4-dinitrochlorobenzene (DNCB) treatment, cKO mice developed worsened AD-like skin inflammation with increased Ki67 cells, decreased filaggrin and loricrin expression, and downregulated S100A9 and LL37. The dominant microbial population in cKO mice changed from to . DNCB-treated cKO mice displayed more infiltrating type-2 inflammatory cells, including mast cells, eosinophils, and CD4T cells, accompanied by increased skin IL-4 and serum IgE levels. Moreover, thymic stromal lymphopoietin (TSLP), mainly produced by keratinocytes, was highly expressed in the ear skin of cKO mice and chemoattracted more TSLPR cells. TSLP blockade significantly alleviated DNCB-induced AD-like skin inflammation in cKO mice. Thus, epidermal keratinocyte-specific STAT3 deficiency can aggravate AD-like skin inflammation in mice, possibly through TSLP dysregulation.
Topics: Animals; Mice; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Inflammation; Keratinocytes; STAT3 Transcription Factor; Thymic Stromal Lymphopoietin; Up-Regulation
PubMed: 38053996
DOI: 10.3389/fimmu.2023.1273182 -
British Journal of Pharmacology Dec 2023Pruritic dermatitis is a disease with a considerable unmet need for treatment and appears to present with not only epidermal but also peripheral neuronal complications....
BACKGROUND AND PURPOSE
Pruritic dermatitis is a disease with a considerable unmet need for treatment and appears to present with not only epidermal but also peripheral neuronal complications. Here, we propose a novel pharmacological modulation targeting both peripheral dorsal root ganglion (DRG) sensory neurons and skin keratinocytes. GPR35 is an orphan G-protein-coupled receptor expressed in DRG neurons and has been predicted to downregulate neuronal excitability when activated. Modulator information is currently increasing for GPR35, and pamoic acid (PA), a salt-forming agent for drugs, has been shown to be an activator solely specific for GPR35. Here, we investigated its effects on dermatitic pathology.
EXPERIMENTAL APPROACH
We confirmed GPR35 expression in peripheral neurons and tissues. The effect of PA treatment was pharmacologically evaluated in cultured cells in vitro and in in vivo animal models for acute and chronic pruritus.
KEY RESULTS
Local PA application mitigated acute non-histaminergic itch and, consistently, obstructed DRG neuronal responses. Keratinocyte fragmentation under dermatitic simulation was also dampened following PA incubation. Chronic pruritus in 1-chloro-2,4-dinitrobenzene and psoriasis models were also moderately but significantly reversed by the repeated applications of PA. Dermatitic scores in the 1-chloro-2,4-dinitrobenzene and psoriatic models were also improved by its application, indicating that it is beneficial for mitigating disease pathology.
CONCLUSION AND IMPLICATIONS
Our findings suggest that pamoic acid activation of peripheral GPR35 can contribute to the improvement of pruritus and its associated diseases.
Topics: Animals; Dinitrochlorobenzene; Pruritus; Skin; Dermatitis; Ganglia, Spinal
PubMed: 37501600
DOI: 10.1111/bph.16201 -
Phytomedicine : International Journal... Jul 2023Atopic dermatitis (AD) is a chronic, relapsing skin disease accompanied by itchy and dry skin. AD is caused by complex interactions between innate and adaptive immune...
Anti-inflammatory effect and metabolic mechanism of BS012, a mixture of Asarum sieboldii, Platycodon grandiflorum, and Cinnamomum cassia extracts, on atopic dermatitis in vivo and in vitro.
BACKGROUND
Atopic dermatitis (AD) is a chronic, relapsing skin disease accompanied by itchy and dry skin. AD is caused by complex interactions between innate and adaptive immune response. AD treatment include glucocorticoids and immunosuppressants. However, long-term treatment can have serious side effects. Thus, an effective AD treatment with fewer side effects is required. Natural materials, including herbal medicines, have potential applications.
PURPOSE
This study evaluated the in vivo and in vitro therapeutic effects of BS012, a mixture of Asarum sieboldii, Platycodon grandiflorum, and Cinnamomum cassia extracts, on AD and investigated the underlying metabolic mechanisms.
METHODS
The anti-inflammatory effects of BS012 were assessed using a mouse model of AD induced by 1‑chloro-2,4-dinitrobenzene (DNCB) and in tumor necrosis factor-alpha/interferon-gamma (TNF-α/IFN-γ) stimulated normal human epidermal keratinocytes (NHEKs). In DNCB-induced mice, total dermatitis score, histopathological analysis, and immune cell factors were assessed to evaluate the anti-atopic activity. In TNF-α/IFN-γ-stimulated NHEKs, pro-inflammatory cytokines, chemokines, and related signaling pathways were investigated. Serum and intracellular metabolomics were performed to identify the metabolic mechanism underlying the therapeutic effects of BS012 treatment.
RESULTS
In DNCB-induced mice, BS012 showed potent anti-atopic activity, including reducing AD-like skin lesions and inhibiting the expression of Th2 cytokines and thymic stromal lymphopoietin. In TNF-α/IFN-γ-stimulated keratinocytes, BS012 dose-dependently inhibited the expression of pro-inflammatory cytokines and chemokines by blocking nuclear factor-kappa B and signal transducer and activator of transcription signaling pathways. Serum metabolic profiles of mice revealed significant changes in lipid metabolism related to inflammation in AD. Intracellular metabolome analysis revealed that BS012 treatment affected the metabolism associated with inflammation, skin barrier function, and lipid organization of the stratum corneum.
CONCLUSION
BS012 exerts anti-atopic activity by reducing the Th2-specific inflammatory response and improving skin barrier function in AD in vivo and in vitro. These effects are mainly related to the inhibition of inflammation and recovery of metabolic imbalance in lipid organization. BS012, a novel combination with strong activity in suppressing the Th2-immune response, could be a potential alternative for AD treatment. Furthermore, the metabolic mechanism in vivo and in vitro using a metabolomics approach will provide crucial information for the development of natural products for AD treatment.
Topics: Humans; Animals; Mice; Dermatitis, Atopic; Platycodon; Asarum; Cinnamomum aromaticum; Tumor Necrosis Factor-alpha; Dinitrochlorobenzene; Anti-Inflammatory Agents; Cytokines; Inflammation; Chemokines; Interferon-gamma; Dinitrobenzenes; Lipids; Skin; Mice, Inbred BALB C
PubMed: 37187105
DOI: 10.1016/j.phymed.2023.154818 -
Molecules (Basel, Switzerland) Jul 2023Formononetin (FNT) is a plant-derived isoflavone natural product with anti-inflammatory, antioxidant, and anti-allergic properties. We showed previously that FNT...
Formononetin (FNT) is a plant-derived isoflavone natural product with anti-inflammatory, antioxidant, and anti-allergic properties. We showed previously that FNT inhibits immunoglobulin E (IgE)-dependent mast cell (MC) activation, but the effect of FNT on IgE-independent MC activation is yet unknown. Our aim was to investigate the effects and possible mechanisms of action of FNT on IgE-independent MC activation and pseudoallergic inflammation. We studied the effects of FNT on MC degranulation in vitro with a cell culture model using compound C48/80 to stimulate either mouse bone marrow-derived mast cells (BMMCs) or RBL-2H3 cells. We subsequently measured β-hexosaminase and histamine release, the expression of inflammatory factors, cell morphological changes, and changes in NF-κB signaling. We also studied the effects of FNT in several in vivo murine models of allergic reaction: C48/80-mediated passive cutaneous anaphylaxis (PCA), active systemic anaphylaxis (ASA), and 2,4-dinitrobenzene (DNCB)-induced atopic dermatitis (AD). The results showed that FNT inhibited IgE-independent degranulation of MCs, evaluated by a decrease in the release of β-hexosaminase and histamine and a decreased expression of inflammatory factors. Additionally, FNT reduced cytomorphological elongation and F-actin reorganization and attenuated NF-κB p65 phosphorylation and NF-κB-dependent promoter activity. Moreover, the administration of FNT alleviated pseudoallergic responses in vivo in mouse models of C48/80-stimulated PCA and ASA, and DNCB-induced AD. In conclusion, we suggest that FNT may be a novel anti-allergic drug with great potential to alleviate pseudoallergic responses via the inhibition of IgE-independent MC degranulation and NF-κB signaling.
Topics: Mice; Animals; Mast Cells; p-Methoxy-N-methylphenethylamine; NF-kappa B; Cell Degranulation; Dinitrochlorobenzene; Anaphylaxis; Isoflavones; Immunoglobulin E; Anti-Allergic Agents
PubMed: 37446928
DOI: 10.3390/molecules28135271 -
Biomedicine & Pharmacotherapy =... Mar 2024Atopic dermatitis (AD) is a chronic inflammatory skin condition primarily driven by T helper 2 (Th2) cytokines, resulting in skin barrier defects, angiogenesis, and...
Atopic dermatitis (AD) is a chronic inflammatory skin condition primarily driven by T helper 2 (Th2) cytokines, resulting in skin barrier defects, angiogenesis, and inflammatory responses. The marine natural product excavatolide B (EXCB), isolated from the Formosan Gorgonian coral Briareum stechei, exhibits anti-inflammatory and analgesic properties. To enhance solubility, EXCB is chemically modified into the derivatives EXCB-61 salt and EXCB-79. The study aims to investigate the therapeutic effects of these compounds on dinitrochlorbenzene (DNCB)-induced skin damage and to elucidate the underlying anti-inflammatory and anti-angiogenesis mechanism. In vitro, using lipopolysaccharide (LPS)-induced RAW 264.7 cells, all compounds at 10 μM significantly inhibited expression of inflammatory proteins (inducible nitric oxide synthase and cyclooxygenase-2), vascular endothelial growth factor (VEGF), and cytokines (interleukin (IL)-1β, IL-6, and IL-17A). In vivo, topical application of these compounds on DNCB-induced AD mice alleviated skin symptoms, reduced serum levels of IgE, IL-4, IL-13, IL-17, and interferon-γ, and moderated histological phenomena such as hyperplasia, inflammatory cell infiltration, and angiogenesis. The three compounds restored the expression of skin barrier-related proteins (loricrin, filaggrin, and claudin-1) and reduced the expression of angiogenesis-related proteins (VEGF and platelet endothelial cell adhesion molecule-CD31) in the tissues. This is the first study to indicate that EXCB, EXCB-61 salt, and EXCB-79 can treat AD disease by reducing inflammation and angiogenesis. Hence, they may be considered potential candidates for the development of new drugs for AD.
Topics: Animals; Mice; Dermatitis, Atopic; Angiogenesis Inhibitors; Vascular Endothelial Growth Factor A; Dinitrochlorobenzene; Cytokines; Angiogenic Proteins; Anti-Inflammatory Agents; Diterpenes
PubMed: 38368838
DOI: 10.1016/j.biopha.2024.116279 -
The Journal of Investigative Dermatology Feb 2024This study investigated the role of CD226 in a 2,4-dinitrochlorobenzene (DNCB)-induced mouse model of atopic dermatitis. The results showed that the lack of CD226...
This study investigated the role of CD226 in a 2,4-dinitrochlorobenzene (DNCB)-induced mouse model of atopic dermatitis. The results showed that the lack of CD226 (global and CD4 T-cell specific) significantly increased ear thickness, reddening, swelling, and scaling of the skin as well as inflammatory cell and mast cell infiltration. RT-qPCR results demonstrated that the mRNA expressions of atopic dermatitis-related inflammatory cytokines and chemokines were markedly increased in the draining lymph nodes and lesioned ear skin tissues of global and CD4 T-cell-specific CD226-deficient mice compared with that in control mice. In vitro assessment revealed that CD226 directly modulates TGFβ-mediated regulatory T (Treg) cell differentiation and proliferation. Notably, Treg cell-specific deletion of CD226 (Cd226Foxp3 mice) resulted in more severe dermatitis and epidermal thickening than those observed in littermate mice upon DNCB treatment. Subsequent analysis showed that the infiltration of Treg cells in ear lesions and the number of Tregs in the spleen were significantly reduced in Cd226Foxp3 mice after DNCB treatment. In addition, the lack of CD226 induced apoptosis of Treg cells through the activation of caspase 3. Therefore, these results suggest that CD226 has potential efficacy in atopic dermatitis, correlating with Treg cell inhibition.
PubMed: 38325579
DOI: 10.1016/j.jid.2024.01.022 -
Chinese Medicine Aug 2023The aryl hydrocarbon receptor (AhR) is a transcription factor that plays a crucial role in regulating the immune system and maintaining skin barrier function. AhR...
BACKGROUND
The aryl hydrocarbon receptor (AhR) is a transcription factor that plays a crucial role in regulating the immune system and maintaining skin barrier function. AhR signaling is pivotal in the pathogenesis of inflammatory diseases such as atopic dermatitis (AD), and the absence of AhR ligands further contributes to the progression or worsening of AD symptoms.
METHODS
AD was induced with 2,4-dinitrochlorobenzene (DNCB), and Bojungikgi-tang (BJIKT) was administered orally daily for 10 weeks. Serum IgE, splenocyte IL-4, and IFN-γ levels, skin barrier genes, and AhR target gene expressions were analyzed using RNA-sequencing analysis. Spleen tissues were extracted for fluorescence-activated cell sorting (FACS) analysis to analyze the effect of BJIKT on immune responses. A correlation analysis was conducted to analyze the correlation between immune markers and skin barrier genes and AhR target genes.
RESULTS
BJIKT effectively improved AD symptoms in AD mice fed a low AhR ligand diet by reducing neutrophil and eosinophil counts, lowering IgE levels in the blood, and decreasing IL-4 and IFN-γ levels in the splenocytes. Additionally, BJIKT significantly reduced epithelial skin thickness and transepidermal water loss (TEWL) values and reversed the decreased expression of skin barrier genes. BJIKT also considerably altered the expression of AhR target genes, including Ahr, Ahrr, cytochrome P450 1A1 (CYP1A1), and CYP1B1. Furthermore, AhR target pathway genes were negatively correlated with immune cell subtypes, including CD4 + and CD8 + T cells and macrophages (CD11b + F4/80 +) at the systemic level.
CONCLUSIONS
BJIKT can regulate AhR activation and may help reduce inflammation in AD by regulating the expression of skin barrier genes and immune responses.
PubMed: 37573390
DOI: 10.1186/s13020-023-00806-9