Coffea arabica Extract Attenuates Atopic Dermatitis-like Skin Lesions by Regulating NLRP3 Inflammasome Expression and Skin Barrier Functions.

Atopic dermatitis (AD) is a common skin disease worldwide. The major causes of AD are skin barrier defects, immune dysfunction, and oxidative stress. In this study, we investigated the anti-oxidation and anti-inflammation effects of Coffea arabica extract (CAE) and its regulation of the skin barrier and immune functions in AD. In vitro experiments revealed that CAE decreased the reactive oxygen species levels and inhibited the translocation of nuclear factor-κB (NF-κB), further reducing the secretion of interleukin (IL)-1ß and IL-6 induced by interferon-γ (IFN-γ)/tumor necrosis factor-α (TNF-α). Moreover, CAE decreased IFN-γ/TNF-α-induced NLR family pyrin domain-containing 3 (NLRP3), caspase-1, high-mobility group box 1 (HMGB1), and receptor for advanced glycation end products (RAGE) expression levels. It also restored the protein levels of skin barrier function-related markers including filaggrin and claudin-1. In vivo experiments revealed that CAE not only reduced the redness of the backs of mice caused by 2,4-dinitrochlorobenzene (DNCB) but also reduced the levels of pro-inflammatory factors in their skin. CAE also reduced transepidermal water loss (TEWL) and immune cell infiltration in DNCB-treated mice. Overall, CAE exerted anti-oxidation and anti-inflammation effects and ameliorated skin barrier dysfunction, suggesting its potential as an active ingredient for AD treatment.

Anti-Atopic Effect of Isatidis Folium Water Extract in TNF-α/IFN-γ-Induced HaCaT Cells and DNCB-Induced Atopic Dermatitis Mouse Model.

Isatidis folium or Isatis tinctoria L. is a flowering plant of the Brassicaceae family, commonly known as woad, with an ancient and well-documented history as an indigo dye and medicinal plant. This study aimed to evaluate the anti-atopic dermatitis (AD) effects of Isatidis folium water extract (WIF) using a 2,4-dinitrochlorobenzene (DNCB)-induced AD-like mouse model and to investigate the underlying mechanism using tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)-activated HaCaT cells. Oral administration of WIF reduced spleen weight, decreased serum IgE and TNF-α levels, reduced epidermal and dermal thickness, and inhibited eosinophil and mast cell recruitment to the dermis compared to DNCB-induced control groups. Furthermore, oral WIF administration suppressed extracellular signal-regulated kinase and p38 mitogen-activated protein kinase protein expression levels, p65 translocation from the cytoplasm to the nucleus, and mRNA expression of TNF-α, IFN-γ, interleukin (IL)-6, and IL-13 in skin lesion tissues. In HaCaT cells, WIF suppressed the production of regulated upon activation, normal T cell expressed and secreted (RANTES), thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), MCP-1, and MIP-3a, which are inflammatory cytokines and chemokines related to AD, and inhibited the mRNA expression of RANTES, TARC, and MDC in TNF-α/IFN-γ-stimulated HaCaT cells. Overall, the results revealed that WIF ameliorated AD-like skin inflammation by suppressing proinflammatory cytokine and chemokine production via nuclear factor-κB pathway inhibition, suggesting WIF as a potential candidate for AD treatment.

The Anti-Atopic Dermatitis Effects of Mentha arvensis Essential Oil Are Involved in the Inhibition of the NLRP3 Inflammasome in DNCB-Challenged Atopic Dermatitis BALB/c Mice.

The NLRP3 inflammasome is upregulated by various agents, such as nuclear factor-kappa B (NF-κB), lipopolysaccharide (LPS), and adenosine triphosphate (ATP). The NLRP3 inflammasome facilitations the maturation of interleukin (IL)-1ß, a proinflammatory cytokine that is critically involved in the pathogenesis of atopic dermatitis (AD). Although the NLRP3 inflammasome clearly exacerbates AD symptoms such as erythema and pruritus, drugs for AD patients targeting the NLRP3 inflammasome are still lacking. Based on the previous findings that Mentha arvensis essential oil (MAEO) possesses strong anti-inflammatory and anti-AD properties through its inhibition of the ERK/NF-κB signaling pathway, we postulated that MAEO might be capable of modulating the NLRP3 inflammasome in AD. The aim of this research was to investigate whether MAEO affects the inhibition of NLRP3 inflammasome activation in murine bone marrow-derived macrophages (BMDMs) stimulated with LPS + ATP in vitro and in a murine model displaying AD-like symptoms induced by 2,4-dinitrochlorobenzene (DNCB) in vivo. We found that MAEO inhibited the expression of NLRP3 and caspase-1, leading to the suppression of NLRP3 inflammasome activation and IL-1ß production in BMDMs stimulated with LPS + ATP. In addition, MAEO exhibited efficacy in ameliorating AD symptoms in a murine model induced by DNCB, as indicated by the reduction in dermatitis score, ear thickness, transepidermal water loss (TEWL), epidermal thickness, and immunoglobulin E (IgE) levels. Furthermore, MAEO attenuated the recruitment of NLRP3-expressing macrophages and NLRP3 inflammasome activation in murine dorsal skin lesions induced by DNCB. Overall, we provide evidence for the anti-AD effects of MAEO via inhibition of NLRP3 inflammasome activation.

Estrogen Receptor Alpha Gene (ESR1) Facilitates Th2-immune Response and Enhances Th2 Cytokines in Experimental Atopic Dermatitis Mice.

Background: Molecular markers are involved in atopic dermatitis (AD) pathogenesis. The estrogen receptor (ESR)-1 gene, encoding ERα, is reported to express aberrantly in AD patients. Objective: To detect the biological functions of ESR1 in 2,4 dinitrochlorobenzene (DNCB)-treated mice. Methods: The DNCB-treated mice received a topical application of emulsion containing the 1,3-bis(4 hydroxyphenyl)-4-methyl-5-[4-(2-piperidinyl ethoxy) phenol]-1H-pyrazole dihydrochloride (MPP; an ESR1-selective antagonist) to dorsal skins and ears. Then the dermatitis scores, histopathological changes, and cytokine levels were evaluated. Results: MPP specifically downregulated ESR1 expression in DNCB-applied mice. Functionally, application of MPP abolished the DNCB-induced promotion in dermatitis score. Additionally, MPP administration protected against DNCB-induced dermatitis severity, suppressed mast cell infiltration and reduced production of immunoglobulin E (IgE) and thymus and activation-regulated chemokine (TARC). Moreover, MPP treatment inhibited DNCB-induced production of Th2 cytokines and infiltration of CD4+ T cells. Conclusion: ESR1 facilitates Th2-immune response and enhances Th2 cytokines in AD mice.

A New Moisturiser Improves DNCB-induced Atopic Dermatitis-like Symptoms and Restores Skin Barrier Function in BALB/c Mice.

INTRODUCTION: Atopic dermatitis (AD) is a chronic, inflammatory skin disorder with eczematous and pruritic lesions. Topical moisturisers and either topical corticosteroids or calcineurin inhibitors are usually recommended. Restoring the skin barrier function alleviates AD symptoms. OBJECTIVE: To evaluate the efficacy of a new moisturiser compared to commercially available products in an AD murine model. METHODS: Experimental AD was induced with topical applications of 2,4-DiNitroChloroBenzene (DNCB) on the shaved back skin of BALB/c mice from Day 1 to Day 38. Mice were randomized to either Vehicle/-, DNCB/-, or DNCB/Eczekalm (test product), DNCB/Atopiclair®, or DNCB/Lipikar (reference products) groups. Once daily application of either Eczekalm or Atopiclair® or Lipikar on the AD lesion was performed from Day 32 to Day 38. The AD severity index (ADSI) and animal behaviour were monitored throughout the study. The trans-epidermal water loss (TEWL) was measured on the sacrifice day (Day 39). RESULTS: At Day39, ADSI in the DNCB/Eczekalm, DNCB/Lipikar, and DNCB/Atopiclair® groups were significantly lower by -70%, -68%, and -57%, respectively, as compared to DNCB/- (p < 0.001). No sign of erythema was observed in the DNCB/Eczekalm group. Mean scores of skin oedema, excoriation, and dryness in the DNCB/Eczekalm, DNCB/Lipikar, and DNCB/Atopiclair® groups were significantly lower than in the DNCB/-. No significant difference was observed between DNCB/Eczekalm and DNCB/Lipikar groups. Mean TEWL in DNCB/Eczekalm group was significantly lower than the ones of DNCB/Atopiclair® (-43%, p < 0.001) and DNCB/Lipikar (-15%, p < 0.05). CONCLUSION: Eczekalm treatment significantly reduced the inflammatory effects due to AD and itching episodes and restored the skin barrier function.

Lupeol alleviates atopic dermatitis-like skin inflammation in 2,4-dinitrochlorobenzene/Dermatophagoides farinae extract-induced mice.

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects from children to adults widely, presenting symptoms such as pruritus, erythema, scaling, and dryness. Lupeol, a pentacyclic triterpenoid, has anti-inflammatory and antimicrobial activities. Based on these properties, the therapeutic effects of lupeol on skin disorders have been actively studied. In the present study, we aimed to determine the effectiveness of lupeol on AD. METHODS: We utilized tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated keratinocytes and 2, 4-dinitrochlorobenzene/Dermatophagoides farinae extract (DFE)-induced AD mice to confirm the action. RESULTS: Lupeol inhibited TNF-α/IFN-γ-stimulated keratinocytes activation by reducing the expressions of pro-inflammatory cytokines and chemokines which are mediated by the activation of signaling molecules such as signal transducer and activator of transcription 1, mitogen-activated protein kinases (p38 and ERK), and nuclear factor-κB. Oral administration of lupeol suppressed epidermal and dermal thickening and immune cell infiltration in ear tissue. Immunoglobulin (Ig) E (total and DFE-specific) and IgG2a levels in serum were also reduced by lupeol. The gene expression and protein secretion of T helper (Th) 2 cytokines, Th1 cytokines, and pro-inflammatory cytokine in ear tissue were decreased by lupeol. CONCLUSIONS: These results suggest that lupeol has inhibitory effects on AD-related responses. Therefore, lupeol could be a promising therapeutic agent for AD.

CD226 deficiency exacerbated intestinal immune dysregulation in mice with dinitrochlorobenzene-induced atopic dermatitis.

Intestinal mucosal immunity plays a pivotal role in host defence. In this study, we found that cluster of differentiation 226 (CD226) gene knockout (KO) led to more severe atopic dermatitis (AD)-related skin pathologies and bowel abnormalities in a 2,4-dinitrochlorobenzene (DNCB)-induced AD-like mouse model. Following DNCB administration, the expression of CD226 was elevated in intestinal mucosal tissues, including group 3 innate lymphoid cells (ILC3s) and CD4+ T cells of Peyer's patches (PPs). CD226 deficiency led to an overactive intestinal immune response in the AD-like mice, as evidenced by increased inflammation and Th1/Th2-related cytokine levels as well as increased Paneth cell numbers and antimicrobial peptide (AMP) expression, which was likely due to the higher interleukin (IL)-22 production in the lamina propria. Additionally, CD226 deficiency increased the production of IL-4 and IL-17 in mesenteric lymph nodes as well as the number of PPs and expression of immunoglobulin (Ig) A in B cells. Moreover, insufficient expression of CD226 affected the characterization of intraepithelial and lamina propria lymphocytes in the intestinal mucosa. Finally, the number of PPs was increased in CD4+ T cell-specific CD226 KO and regulatory T (Treg) cell-specific CD226 KO mice; thus, loss of CD226 in Treg cells resulted in impaired Treg cell-suppressive function. Therefore, our findings indicate that CD226 deficiency alters intestinal immune functionality in inflammatory diseases.

Dissolvable Microneedle Patch Increases the Therapeutic Effect of Jawoongo on DNCB-Induced Atopic Dermatitis in Mice.

BACKGROUND: Jawoongo (JW) is a topical herbal ointment that has been used as an alternative treatment option for atopic dermatitis. Topical ointments are known to have less bioavailability because the stratum corneum allows only lipophilic and low molecular weight drugs to pass across it. This study aimed to investigate whether applying microneedle patches (MNP) increases the therapeutic effect of 2,4-dinitrochlorobenzene (DNCB)+JW for atopic dermatitis by enhancing transdermal delivery. METHODS: Atopic dermatitis was induced by DNCB in BALB/c mice. The combination treatment of JW and MNP was estimated to study the effect of MNP in improving transdermal delivery. Histological analysis, quantitative real-time PCR (qPCR), and immunofluorescence were performed to verify the effect of MNP in enhancing the therapeutic effects of DNCB+JW on atopic dermatitis in mice. RESULTS: Both combination treatment and DNCB+JW treatment ameliorated histological alterations and reduced skin thickness and infiltration of CD4+ T cells in atopic dermatitis-like skin lesions in DNCB-exposed BALB/c mice. However, the improvement of histological alterations was better in the combination treatment, which was almost normal. Furthermore, the combination treatment exhibited a larger decrease in mRNA levels of IL-4, IL-6, IL-13, iNOS, and TNF-α, compared to DNCB+JW only. In addition, skin thickness and infiltration of CD4+ T cells in the sensitized skin were significantly lower using the combination treatment than using DNCB+JW only. CONCLUSION: Combination treatment with JW and MNP further decreased skin thickness and several inflammatory cytokines in atopic dermatitis like skin lesions compared to treatment using JW alone. These findings suggest that applying a dissolvable MNP after JW application could be useful for treating atopic dermatitis.

Anti-inflammatory effects of amarogentin on 2,4-dinitrochlorobenzene-induced atopic dermatitis-like mice and in HaCat cells.

BACKGROUND: Amarogentin (AMA) is a secoiridoid glycoside extracted from Swertia and Gentiana roots and exhibits many biological effects such as antioxidative, anti-inflammatory, and antitumor activities. Atopic dermatitis (AD) is a chronic inflammatory skin disease caused by disorders in the regulation of multiple inflammatory cytokines. No effective cure has been found for AD now. METHODS: We constructed the HaCat and splenocyte model and tested the inhibitory effect of AMA on IL-4, IL-6, and IL-13 secretions using enzyme-linked immunosorbent assay (ELISA). The AD mouse model was constructed and treated with AMA, the severity of skin lesions was observed, epidermal tissue was collected, and epidermal thickness and mast cell infiltration were observed using hematoxylin and eosin and toluidine blue staining, respectively. The expression of kallikrein-related peptidase 7 (KLK7) and filaggrin (FLG) was detected using immunostaining and Western blot analysis. The mRNA expression of KLK7 and FLG was detected using quantitative polymerase chain reaction (qPCR). Blood immunoglobulin E (IgE) secretion was detected. RESULTS: AMA inhibited IL-6 secreted by tumor necrosis factor (TNF)-α-induced HaCaT cells and reduced IL-4 and IL-13 secreted by phytohemagglutinin (PHA)-induced primary cells in the mice spleen. It was found that the treatment of AMA with 2,4-dinitrochlorobenzene-induced AD-like mice could promote the recovery of dermatitis, reduce the score of dermatitis severity and the scratching frequency, treat the skin lesions, reduce the epidermal thickness, decrease the infiltration of mast cells, reduce the IgE level in serum, decrease the expression levels of AD-related cytokines, increase protein and mRNA expression of FLG, and reduce the protein and mRNA expression of KLK7 in the skin tissues of AD-like mice. CONCLUSION: In conclusion, AMA inhibits inflammatory response at the cellular level, and AMA reduces the validation response of specific dermatitis mice, relieves pruritus, and repairs the damaged skin barrier.

Daphnetin contributes to allergen-induced Th2 cytokine expression and type 2-immune responses in atopic dermatitis and asthma.

Daphne koreana Nakai is a cherished medicinal plant in the Changbai Mountain region of China. It can be incorporated into medicinal meals and used for various skin diseases by infiltrating liquor. Daphnetin (7,8-dihydroxycoumarin, Dap.) is a main constituent of D. koreana Nakai, which has been used to treat inflammatory conditions and immune disorders due to its numerous pharmacological activities, including anti-oxidant, anti-inflammatory, analgesic, etc. Atopic dermatitis (AD) and allergic asthma are typical diseases of type 2-immune responses. In the present study, the therapeutic potential of Dap. against AD and allergic asthma was investigated using animal and cell experiments. AD-like lesions were induced by repeated application of 1-chloro-2,4-dinitrobenzene (DNCB) to the shaved dorsal skin of BALB/c mice. Ovalbumin (OVA) induction was utilized to establish a mouse asthma model. A passive cutaneous anaphylaxis (PCA) mouse ear model and immunoglobulin E (IgE)/bovine serum albumin (BSA)-stimulated RBL-2H3 cells were used for in vitro assays. The skin lesions and serum and tissue homogenates of the mice were analyzed using histological analysis, immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA), respectively, in order to investigate the anti-AD effects of Dap. Histological analysis was performed on the allergic asthma model to observe inflammatory cell infiltration in the lung tissues. Total IgE and OVA-specific IgE in the serum were measured by ELISA. The levels of inflammatory cytokines in BALF were detected by ELISA. In addition, ELISA and western blotting were performed for the in vitro analysis of RBL-2H3 cells. The results showed that Dap. inhibited the development of DNCB-induced AD-like lesions in the BALB/c mice by reducing the severity of the lesions, epidermal thickness and mast cell infiltration; this was accompanied by reduced levels of IgE and inflammatory cytokines [interleukin (IL)-4, IL-5, IL-9, IL-13, IL-33 and thymic stromal lymphopoietin (TSLP)]. In the allergic asthma model, Dap. reduced the number of infiltrated inflammatory cells in the lung tissues. Moreover, the levels of total serum IgE and OVA-specific IgE were reduced in the high daphnetin dose groups (Dap., -100 mg kg-1). Dap. administered at a dose of -100 mg kg-1 decreased the levels of inflammatory cytokines (IL-4, IL-5, IL-9, IL-13, IL-33 and TSLP in BALF). Furthermore, Dap. administered to IgE-sensitized mice effectively attenuated the IgE-triggered PCA reaction. In vitro, Dap. decreased the expression levels of histamine, IL-4, IL-6, IL-13, MIP-1α and INF-α, and reduced the protein expression levels of phosphorylated MAPKs, P-Lyn and P-syk in the RBL-2H3 cells. Therefore, Dap. can be represented as a potential therapeutic strategy for the treatment of allergic inflammatory conditions via immunoregulation.

Ameliorative Effects of Daphnopsis costaricensis Extract against Oxazolone-Induced Atopic Dermatitis-like Lesions in BALB/c Mice.

The genus Daphnopsis has been traditionally used as a purgative, diuretic, stimulant, and psoriasis treatment. In this study, the anti-AD (atopic dermatitis) activities of the Daphnopsis costaricensis EtOH extract (DCE) were investigated in an oxazolone (OX)-induced mouse model of AD, and the anti-inflammatory effects of its active compounds were confirmed in PI-sensitized or IgE/DNP-BSA-sensitized RBL-2H3 cells. DCE improved the symptoms of OX-induced inflammatory dermatitis (swelling, erythema, and increased ear thickening) in OX-induced BALB/c mice ears and reduced epidermal thickness and mast cell infiltration. Eleven flavonoid compounds were isolated from DCE, and two compounds (7,8-dimethoxyflavone and 7,2'-dimethoxyflavone) significantly inhibited IL-4 overexpression in PI-induced RBL-2H3 cells and mast cell degranulation in IgE + DNP-BSA-induced RBL-2H3 cells. Our study indicates that DCE and two compounds (7,8-dimethoxyflavone and 7,2'-dimethoxyflavone) might effectively improve inflammatory and atopic skin symptoms.

Regulatory Effects of Lycium barbarum Extract and Isolated Scopoletin on Atopic Dermatitis-Like Skin Inflammation.

Lycium barbarum and scopoletin are widely used in oriental Eastern medicine and are often consumed as teas. In this study, proinflammatory cytokines expressed in human keratinocytes (HaCaT) were induced by skin diseases caused by 2,4-dinitrochlorobenzene (DNCB) and tumor necrosis factor alpha (TNF-α)/interferon gamma (IFN-γ). The inhibitory activity of L. barbarum EtOH extract (LBE) and scopoletin on proinflammatory cytokines and chemokines was investigated. In the DNCB-induced animal model, oral administration of LBE inhibited skin lesions and proinflammatory cytokines and chemokines and showed inhibitory effects in vitro. Additionally, as a result of examining the efficacy of scopoletin isolated from L. barbarum, scopoletin in HaCaT cells showed inhibitory effects on proinflammatory cytokines and chemokines. It shows promise in the treatment of chronic skin diseases.

Association of heat shock protein 8 with atopic march in a murine experimental model.

Background: Atopic march (AM), a unique characteristic of allergic diseases, refers to the sequential progression of atopic dermatitis (AD) in infants to allergic asthma and allergic rhinitis in children and young adults, respectively. Although there are several studies on AM, the establishment of an AM murine model to expand our understanding of the underlying mechanism and to identify the potential biomarkers is yet to be achieved. In this study, an improved murine model was established by applying a method to minimize skin irritation in inducing AD, and it was used to perform integrated analyses to discover candidate biomarkers. Methods: To induce atopic dermatitis, 2,4-dinitrochlorobenzene (DNCB) was applied to the ear skin once a week, and this was continued for 5 weeks. From the second application of DNCB, Dermatophagoides pteronyssinus (Dp) extract was applied topically 2 days after each DNCB application; this was continued for 4 weeks. Dp sensitization and intranasal challenges were then performed for 4 weeks to develop conditions mimicking AM. Results: Exacerbated airway inflammation and allergic responses observed in the AM-induced group suggested successful AM development in our model. Two-dimensional gel electrophoresis (2-DE) and mass spectrometry analysis identified 753 candidate proteins from 124 2-DE spots differentially expressed among the experimental groups. Functional analyses, such as Gene Ontology (GO) annotation and protein-protein interaction (PPI) analysis were conducted to investigate the relationship among the candidate proteins. Seventy-two GO terms were significant between the two groups; heat shock protein 8 (Hspa8) was found to be included in six of the top 10 GO terms. Hspa8 scored high on the PPI parameters as well. Conclusion: We established an improved murine model for AM and proposed Hspa8 as a candidate biomarker for AM.

Dendrobium nobile Lindley Administration Attenuates Atopic Dermatitis-like Lesions by Modulating Immune Cells.

Atopic dermatitis (AD) is a chronic inflammatory skin disease that can significantly affect daily life by causing sleep disturbance due to extreme itching. In addition, if the symptoms of AD are severe, it can cause mental disorders such as ADHD and suicidal ideation. Corticosteroid preparations used for general treatment have good effects, but their use is limited due to side effects. Therefore, it is essential to minimize the side effects and study effective treatment methods. Dendrobium nobile Lindley (DNL) has been widely used for various diseases, but to the best of our knowledge, its effect on AD has not yet been proven. In this study, the inhibitory effect of DNL on AD was confirmed in a DNCB-induced Balb/c mouse. In addition, the inhibitory efficacy of inflammatory cytokines in TNF-α/IFN-γ-induced HaCaT cells and PMACI-induced HMC-1 cells was confirmed. The results demonstrated that DNL decreased IgE, IL-6, IL-4, scratching behavior, SCORAD index, infiltration of mast cells and eosinophils and decreased the thickness of the skin. Additionally, DNL inhibited the expression of cytokines and inhibited the MAPK and NF-κB signaling pathways. This suggests that DNL inhibits cytokine expression, protein signaling pathway, and immune cells, thereby improving AD symptoms in mice.

Pinus koraiensis needle or cone extracts alleviate atopic dermatitis symptoms by regulating immunity and suppressing inflammation in HaCaT cells and Nc/Nga mice.

Pinus koraiensis needles (PKN) and cones (PKC) have been shown to protect against inflammation and pathogenic bacteria. We investigated the efficacies and action mechanisms of topical applications of 1,3-butylene glycol (BG) extracts and oral administration of their water extracts on atopic dermatitis (AD) symptoms. After exposing HaCaT cells and Nc/Nga mice dorsal skins to 2,4-dinitrochlorobenzene (DNCB) to induce atopic dermatitis models, they were topically applied BG (AD-control), 30% PKNX, or 30% PKCX to the skin lesions and fed water extracts (0.5%) in high-fat diets for 5 weeks. Normal-control mice had no DNCB exposure. Serum immunoglobulin E (IgE), IL-4, and TNF-α levels and gene expressions of TNF-α, IL-4, IL-6, and IFN-γ in the dorsal skin and HaCaT cells were measured. The AD-control mice elevated TNF-α and IL-6 mRNA levels in HaCaT cells. Both extracts attenuated clinical AD symptoms in AD-induced Nc/Nga mice: PKNX improved hemorrhage, erythema, and lichenification of dorsal skin better than PKCX while both similarly alleviated erythema, edema, excoriation, and itching behavior. PKCX reduced IgE contents and increased filaggrin mRNA expression better than PKNX, but PKNX reduced lipid peroxides and mRNA levels of TNF-α and IL-4 in the dorsal skin. In the histological analysis of the dorsal skin, the administration of both extracts significantly decreased mast cell numbers, immune cell infiltration, gaps between the epidermis and dermis, and abnormal cell and nucleus shapes. In conclusion, both PKCX and PKNX treatment alleviated the DNCB-induced clinical symptoms of AD by alleviating immune-related symptoms and inflammation in partially different pathways. Therefore, PKNX and PKCX may be effective for AD therapy. PRACTICAL APPLICATIONS: Atopic dermatitis (AD) is related to an overly activated immune response, and it has steadily increased last 3 decades. However, no optimal sustainable treatments are available. Pinus koraiensis needles and cones extracts have been used for anti-inflammatory and antimicrobial treatment. The present study demonstrated that their intake and topical administration onto the AD lesion alleviated clinical AD symptoms associated with reduced proinflammatory cytokines, mast cell numbers, and immune cell infiltrates to maintain dermal structure with maintaining filaggrin expression in AD-induced HaCaT cells and Nc/Nga mice. These results suggested that Pinus koraiensis needles and cones extracts can be developed and applied as beneficial alternative therapies for AD.

Wikstroemiaganpi Extract Improved Atopic Dermatitis-Like Skin Lesions via Suppression of Interleukin-4 in 2,4-Dinitrochlorobenzene-Induced SKH-1 Hairless Mice.

Plants of the genus Wikstroemia are used in Chinese traditional medicine to treat inflammatory diseases, such as arthritis, bronchitis, and pneumonia. The present study was designed to determine whether Wikstroemia ganpi (Siebold and Zucc.) Maxim. offers a potential means of treating 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD) in mice. Symptoms such as redness, edema, and keratinization in AD mice induced by DNCB were alleviated by the co-application of an ethanolic extract of W. ganpi for 2 weeks. The severity of skin barrier function damage was evaluated by measuring TEWL (transepidermal water loss). TEWLs of DNCB sensitized mouse dorsal skin were reduced by the application of a W. ganpi ethanolic extract, and skin hydration was increased. In addition, the infiltration of inflammatory cells into the dermis was significantly reduced, as were blood levels of IgE and IL-4, which play an important role in the expression of AD. The results of this experiment suggest that W. ganpi is a potential therapeutic agent for AD.

Effects of mineral complex material treatment on 2,4- dinitrochlorobenzene-induced atopic dermatitis like-skin lesions in mice model.

BACKGROUND: Atopic dermatitis (AD) is a chronic allergic inflammatory skin disease characterized by complex pathogenesis including skin barrier dysfunction, immune-redox disturbances, and pruritus. Prolonged topical treatment with medications such as corticosteroids, calcineurin inhibitors, and T-cell inhibitors may have some potential side-effects. To this end, many researchers have explored numerous alternative therapies using natural products and mineral compounds with antioxidant or immunomodulatory effects to minimize toxicity and adverse-effects. In the current study, we investigated the effects of mineral complex material (MCM) treatment on 2, 4-dinitrochlorobenzene (DNCB)-induced AD-like skin lesions in SKH-1 hairless mice. METHODS: Animals were divided into four groups; normal control (NC), negative control treated with DNCB only (DNCB only), positive control treated with DNCB and tacrolimus ointment (PC) and experimental group treated with DNCB and MCM patch (MCM). Skin inflammation and lesion severity were investigated through analyses of skin parameters (barrier score and strength, moisture and trans-epidermal water loss level), histopathology, immunoglobulin E, and cytokines. In addition, reactive oxygen species (ROS), nitric oxide (NO), glutathione peroxidase (GPx), and catalase (CAT) levels were measured in both serum and skin lysate. RESULTS: Our results demonstrates that MCM patch improved the progression of AD-like skin lesions by significantly increasing skin barrier strength and decreasing trans-epidermal water loss. Additionally, dermal administration of MCM patch significantly reduced epidermal thickness, ROS, and NO levels in skin lysate. Furthermore, we found that MCM suppressed the levels of AD-involved (Th1 and Th2) cytokines such as IL-2, IFN-γ, and IL-4 in blood. In addition, the levels of other Th1, and Th2 and inflammatory cytokines such as IL-1ß, TNF-α, IL-6, IL-12(p70) and IL-10 were found lowest in the MCM group than in the DNCB only and PC groups. Moreover, we found total serum IgE level significantly increased after DNCB treatment, but decreased in the PC and MCM groups. CONCLUSION: Taken together, our findings suggest that MCM application may have beneficial effects either systemic or regional on DNCB-induced AD lesional skin via regulation of the skin barrier function and immune-redox response.

Ameliorative effects of total coumarins from the fructus of Cnidium monnieri (L.) Cuss. on 2,4-dinitrochlorobenzene-induced atopic dermatitis in rats.

Atopic dermatitis (AD), which is characterized by intense pruritus and serious inflammation, is a chronic skin disease. Modern studies have testified that the total coumarins from the fructus of Cnidium monnieri (TCFC) possess evident biological activities based on their coumarin compounds. The purpose of this manuscript is to investigate the effects of topical use of TCFC on immune response, inflammation, and skin barrier function in rats with 2,4-dinitrochlorobenzene (DNCB)-induced AD. Results indicated that the skin lesion scores of rats were obviously reduced after the management of TCFC, and the spleen and thymus indices also were markedly repressed. TCFC significantly inhibited the overproduction of TNF-α, interferon-γ, interleukin (IL)-4, IL-13, thymic stromal lymphopoietin, and immunoglobulin E; the epidermal thickness and number of mast cells were notably decreased. The western blot experiment was conducted to determine the effects of TCFC on the mitogen-activated protein kinases signaling pathway. Results indicated that phosphorylation of extracellular signal-regulated kinases, p38, and c-Jun amino-terminal kinases was significantly blocked by TCFC. In addition, TCFC could upregulate the expression of filaggrin in dorsal skin, which means that TCFC showed a protective effect on skin barrier disruption. Furthermore, TCFC downregulated the levels of IL-1ß, IL-4, IL-31, and TSLP mRNA and upregulated the expression of filaggrin mRNA in the dorsal skin of rats. Our research demonstrated the ameliorative effects of TCFC on AD-like rats by inhibiting immune response and inflammation and recovering skin barrier function.

Deacetylasperulosidic Acid Ameliorates Pruritus, Immune Imbalance, and Skin Barrier Dysfunction in 2,4-Dinitrochlorobenzene-Induced Atopic Dermatitis NC/Nga Mice.

The prevalence of atopic dermatitis (AD), a disease characterized by severe pruritus, immune imbalance, and skin barrier dysfunction, is rapidly increasing worldwide. Deacetylasperulosidic acid (DAA) has anti-atopic activity in the three main cell types associated with AD: keratinocytes, mast cells, and eosinophils. Our study investigated the anti-atopic activity of DAA in 2,4-dinitrochlorobenzene-induced NC/Nga mice. DAA alleviated the symptoms of AD, including infiltration of inflammatory cells (mast cells and eosinophils), epidermal thickness, ear thickness, and scratching behavior. Furthermore, DAA reduced serum IgE, histamine, and IgG1/IgG2a ratio and modulated the levels of AD-related cytokines and chemokines, namely interleukin (IL)-1ß, IL-4, IL-6, IL-9, IL-10, IL-12, tumor necrosis factor-α, interferon-γ, thymic stromal lymphopoietin, thymus and activation-regulated chemokine, macrophage-derived chemokine, and regulated on activation the normal T cell expressed and secreted in the serum. DAA restored immune balance by regulating gene expression and secretion of Th1-, Th2-, Th9-, Th17-, and Th22-mediated inflammatory factors in the dorsal skin and splenocytes and restored skin barrier function by increasing the expression of the pro-filaggrin gene and barrier-related proteins filaggrin, involucrin, and loricrin. These results suggest DAA as a potential therapeutic agent that can alleviate the symptoms of AD by reducing pruritus, modulating immune imbalance, and restoring skin barrier function.

Solanum nigrum Linne improves DNCB­induced atopic dermatitis­like skin disease in BALB/c mice.

The present study aimed to investigate the effects of Solanum nigrum Linne (SNL) in a model of 1­chloro­2,4­dinitrobenzene (DNCB)­induced atopic dermatitis (AD) and in TNF­α/IFN­Î³­stimulated HaCaT cells. AD is a chronic inflammatory skin disease and is characterized by erythema, edema, increased pruritus and eczema. Steroids are most commonly used for anti­inflammatory therapy; however, their long­term use is limited due to side­effects, such as osteoporosis, brittle skin, muscle weaknesses and diabetes. Therefore, patients with AD require alternative treatment strategies. In previous studies, SNL has been reported to be effective against oxidants and cancer. However, to the best of our knowledge, the effects of SNL on AD have not yet been investigated. The present study examined the effects of SNL ethanol extract on a model of DNCB induced AD and on TNF­α/IFN­Î³­stimulated HaCaT cells. The skin tissue was sectioned to measure the thicknesses of the epidermis and dermis, as well as the numbers of eosinophils, mast cells and CD8 infiltration by H&E, toluidine blue, Masson's trichrome and IHC staining. ELISA was performed using serum to measure IgE levels. The present study also examined the expression of various inflammatory cytokines, MAPK and NF­κB in TNF­α/IFN­Î³­stimulated HaCaT cells. SNL significantly reduced the levels of cytokines released from HaCaT cells stimulated with TNF­α/IFN­Î³. SNL also significantly reduced the levels of p­p38 at 30 min and significantly reduced the activation of NF­κB in a time course experiment. In addition, SNL significantly reduced the level of serum IgE and dermal thickness and the infiltration of mast cells and CD8 in the BALB/c mouse model of DNCB­induced AD. The results of the current study suggest that SNL exerts a suppressive effect on pro­inflammatory cytokines in vitro and in vivo through the regulation of the immune system.