oxazolone and Dermatitis--Atopic

Atopic dermatitis (AD) is the most common inflammatory skin condition. Skin barrier dysfunction is of major importance in AD because it facilitates allergen sensitization and systemic allergic responses. Long regarded as a pro-apoptotic protease, emerging studies indicate granzyme B (GzmB) to have extracellular roles involving the proteolytic cleavage of extracellular matrix, cell adhesion proteins, and basement membrane proteins. Minimally expressed in normal skin, GzmB is elevated in AD and is positively correlated with disease severity and pruritus. We hypothesized that GzmB contributes to AD through extracellular protein cleavage. A causative role for GzmB was assessed in an oxazolone-induced murine model of dermatitis, comparing GzmB

Topics: Animals; Cadherins; Dermatitis, Atopic; Epidermis; Extracellular Matrix; Filaggrin Proteins; Granzymes; Humans; Oxazolone; S100 Proteins

Allergic dermatitis (AD) is an inflammatory skin disease that arises from abnormal T lymphocyte activation. A recombinant fusion protein comprising Helicobacter pylori neutrophil-activating protein and maltose binding protein, rMBP-NAP, has been documented as a novel immunomodulatory TLR agonist.. To explore the effect of the rMBP-NAP on the OXA-induced AD in a mouse model and clarify the possible action mechanism.. The AD animal model was induced by repeated administration of oxazolone (OXA) in BALB/c mice. H&E staining was used to analyze the ear epidermis thickness and the number of infiltrating inflammatory cells. TB staining was used to detect mast cell infiltration in the ear tissue. ELISA was used to analyze the secretion of cytokines IL-4 and IFN-γ in peripheral blood. qRT-PCR was used to determine the expression levels of IL-4, IFN-γ, and IL-13 in ear tissue.. OXA induced the establishment of an AD model. After the rMBP-NAP treatment, the thickness of the ear tissue and the number of mast cells infiltrated in AD mice reduced, and the serum and ear tissue levels of IL-4 and IFN-γ increased, but the ratio of IFN-γ (rMBP-NAP group)/IL-4 (rMBP-NAP group) was greater than the ratio of IFN-γ (sensitized group)/IL-4 (sensitized group).. The rMBP-NAP improved the disease symptoms including skin lesions in AD, alleviated the inflammation in ear tissue, and restored the Th1/2 balance by inducing a shift from the Th2 to the Th1 response. The results of our work support the use of rMBP-NAP as an immunomodulator for AD treatment in future investigations.

Topics: Animals; Cytokines; Dermatitis, Atopic; Interleukin-4; Mice; Mice, Inbred BALB C; Oxazolone; Recombinant Fusion Proteins; Th1-Th2 Balance; Th2 Cells

Delivery by cesarean section (CS) is associated with an altered gut microbiota (GM) colonization and a higher risk of later chronic inflammatory diseases. Studies investigating the association between CS and atopic dermatitis (AD) are contradictive and often biased by confounding factors. The aim of this study was therefore to provide experimental evidence for the association between CS and AD in a mouse model and clarify the role of the GM changes associated with CS. It was hypothesized that CS-delivered mice, and human CS-GM transplanted mice develop severe dermatitis due to early dysbiosis. BALB/c mice delivered by CS or vaginally (VD) as well as BALB/c mice transplanted with GM from CS or VD human donors were challenged with oxazolone on the ear. The severity of dermatitis was evaluated by ear thickness and clinical and histopathological assessment which were similar between all groups. The immune response was assessed by serum IgE concentration, local cytokine response, and presence of immune cells in the draining lymph node. Both CS-delivered mice and mice inoculated with human CS-GM had a higher IgE concentration. A higher proportion of Th2 cells were also found in the CS-GM inoculated mice, but no differences were seen in the cytokine levels in the affected ears. In support of the experimental findings, a human cohort analysis from where the GM samples were obtained found that delivery mode did not affect the children's risk of developing AD. In conclusion, CS-GM enhanced a Th2 biased immune response, but had no effect on oxazolone-induced dermatitis in mice.

Topics: Animals; Cesarean Section; Child; Cytokines; Dermatitis, Atopic; Dysbiosis; Female; Gastrointestinal Microbiome; Humans; Immunoglobulin E; Mice; Mice, Inbred BALB C; Oxazolone; Pregnancy

Cutaneous bacterial dysbiosis is a characteristic hallmark of atopic dermatitis (AD), and it decisively influences the severity of the disease. Despite this, frequently used murine models of AD have not been characterized regarding the changes in skin microbiome communities.. To analyse the skin microbiome of two frequently used murine models for AD for assessing their applicability in translational research.. AD was induced in mice by topical application of calcipotriol or oxazolone. Following comparable elicitation of AD-like dermatitis, including IgE induction, the skin microbial communities were analysed and compared with human AD.. We detected critical differences in the microbiota composition of diseased skin. In contrast to calcipotriol treatment, application of oxazolone induced significant changes in the cutaneous microbiota and a drastic drop of bacterial richness. Furthermore, an expansion of Staphylococci, particularly S. xylosus, was observed in the oxazolone group, also displaying positive correlations with AD key markers including pH, TEWL, IL-4, TSLP and IL-33.. In this article, we show that (a) the model of choice to investigate AD needs to be characterized for the cutaneous microbiota if applicable and (b) the oxazolone-mediated mixed Th1-Th2 immune response triggers microbiota-induced alterations which share similarities to dysbiosis in human AD and represents therefore a suitable model for translational research on AD if alterations of the microbiome are in the focus of the investigation.

Topics: Animals; Bacteria; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Dysbiosis; Humans; Interleukin-33; Interleukin-4; Mice; Microbiota; Oxazolone; Skin

Topics: Animals; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Glycine max; Inflammation; Mice; Mice, Inbred BALB C; Oxazolone; Plant Extracts; Skin

7-Met, a derivative of soybean isoflavone, is a natural flavonoid compound that has been reported to have multiple signaling pathways regulation effects. This study investigated the therapeutic effects of 7-Met on mice with atopic dermatitis induced by fluorescein isothiocyanate (FITC), or oxazolone (OXZ). 7-Met ameliorated FITC or OXZ-induced atopic dermatitis symptoms by decreasing ear thickness, spleen index, mast cell activation, neutrophil infiltration and serum IgE levels in female BALB/c mice. In FITC-induced atopic dermatitis mice, 7-Met reduced Th1 cytokines production and regulated Th1/Th2 balance by downregulating the secretion of thymic stromal lymphopoietin (TSLP) via inactivation of the NF-κB pathway. In OXZ-induced atopic dermatitis, 7-Met functioned through the reduction of Th17 cytokine production. Our study showed that 7-Methoxyisoflavone alleviated atopic dermatitis by regulating multiple signaling pathways and downregulating chemokine production.

Topics: Animals; Chemokines; Cytokines; Dermatitis, Atopic; Female; Fluorescein-5-isothiocyanate; Mice; Mice, Inbred BALB C; Oxazolone; Signal Transduction; Skin

Topics: Animals; Cytokines; Dermatitis, Atopic; Dermatitis, Contact; Haptens; Interleukin-13; Interleukin-17; Interleukin-4; Interleukin-5; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Oxazolone; RNA, Messenger; Skin

Laminarin is a polysaccharide isolated from brown marine algae and has a wide range of bioactivities, including immunoregulatory and anti-inflammatory properties. However, the effects of laminarin on atopic dermatitis have not been demonstrated. This study investigated the potential effects of topical administration of laminarin using a Balb/c mouse model of oxazolone-induced atopic dermatitis-like skin lesions. Our results showed that topical administration of laminarin to the ear of the mice improved the severity of the dermatitis, including swelling. Histological analysis revealed that topical laminarin significantly decreased the thickening of the epidermis and dermis and the infiltration of mast cells in the skin lesion. Serum immunoglobulin E levels were also significantly decreased by topical laminarin. Additionally, topical laminarin significantly suppressed protein levels of oxazolone-induced proinflammatory cytokines, such as interleukin-1β, tumor necrosis factor-α, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1α in the skin lesion. These results indicate that topical administration of laminarin can alleviate oxazolone-induced atopic dermatitis by inhibiting hyperproduction of IgE, mast cell infiltration, and expressions of proinflammatory cytokines. Based on these findings, we propose that laminarin can be a useful candidate for the treatment of atopic dermatitis.

Topics: Administration, Topical; Animals; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Immunoglobulin E; Mice; Mice, Inbred BALB C; Oxazolone; Plant Extracts; Skin

Topics: Animals; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Immunoglobulin E; Mast Cells; Mice; Mice, Inbred BALB C; Oxazolone; Plant Extracts; Skin; Thymelaeaceae

Dictamnine is an active pharmaceutical ingredient in Dictamnus dasycarpus, a Chinese herbal medicine widely used for the treatment of skin inflammations such as atopic dermatitis (AD). Oxazolone has been demonstrated to induce significant skin inflammation and produce inflammatory cytokine expression identical to that of AD. An in vitro HaCaT inflammation model treated with dictamnine, which efficiently scavenged the reactive oxygen species (ROS) and mitochondrial ROS (mROS), and it reduced interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) expression, NLRP3 inflammasome activation, and NF-κB expression. To explore the anti-inflammatory mechanism of dictamnine and enhance sustained drug release and penetration into epidermal structures in a dermatitis mouse model, we prepared PLGA-nanocarrier-encapsulated dictamnine (Dic-PLGA-NC) in a specifically designed bioreactor, namely an ultrasound composite streams-impinging mixer (U-SiM). Mouse dermatitis model was treated with Dic-PLGA-NC medication, spleens were collected to evaluate body weight ratio, and skin was retrieved for histological examination and two-photon microscopy. The data demonstrate that Dic-PLGA-NC efficiently penetrated the dermal layer, making it superior to naked dictamnine; moreover, it ameliorated the dermatitis symptoms and inflammatory cytokine expression in vivo. Dic-PLGA-NC produced using the U-SiM bioreactor could be used in new manufacturing processes for drugs to treat AD.

Topics: Animals; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Inflammation; Mice; NF-kappa B; Oxazolone; Quinolines; Skin; Tumor Necrosis Factor-alpha

Epidemiological studies have long reported that perturbations of the childhood microbiome increase the risk of developing allergies, but a causal relationship with atopic dermatitis remains unclear. Here we colonized germ-free mice at birth or at one or eight week-of-age to investigate the role of prenatal and early postnatal microbial exposure on development of oxozolone-induced dermatitis later in life. We demonstrate that only one week delayed microbial colonization increased IgE levels and the total histological score of the inflamed ear compared to mice colonized throughout life. In parallel, several pro-inflammatory cytokines and chemokines were upregulated in the ear tissue demonstrating an enhanced immunological response following delayed postnatal colonization of the gut. In contrast, sensitivity to oxazolone-induced dermatitis was unaffected by the presence of a maternal microbiota during gestation. Mice colonized at eight week-of-age failed to colonize Rikenellaceae, a group of bacteria previously associated with a high-responding phenotype, and did not develop an immunological response to the same extent as the early colonized mice despite pronounced histopathological manifestations. The study provides proof-of-principle that the first intestinal colonizers of mice pups are crucial for the development of oxazolone-induced dermatitis later in life, and that the status of the maternal microbiota during pregnancy has no influence on the offspring's allergic immune response. This highlights an important window of opportunity following birth for microbiota-mediated interventions to prevent atopic responses later in life. How long such a window is open may vary between mice and humans considering species differences in the ontogeny of the immune system.

Topics: Animals; Bacteria; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Dysbiosis; Female; Gastrointestinal Microbiome; Humans; Hypersensitivity; Immunoglobulin E; Mice; Oxazolone; Pregnancy; Prenatal Exposure Delayed Effects; RNA, Ribosomal, 16S

Topics: Animals; Anti-Inflammatory Agents; Boron Compounds; Bridged Bicyclo Compounds, Heterocyclic; Dermatitis, Atopic; Dermatophagoides farinae; Disease Models, Animal; Female; Humans; Leukocytes, Mononuclear; Mice; Oxazoles; Oxazolone; Phosphodiesterase 4 Inhibitors; Piperazines; Severity of Illness Index; Skin; Thiazoles

Atopic dermatitis (AD) is a chronic relapsing inflammatory and pruritic skin disease, affecting 10-20% of the population worldwide. Paeonia suffruticosa Andrews (Paeoniaceae) (Cortex Moutan) and Mentha haplocalyx Briq. (Labiatae) (Herba Menthae) have shown beneficial effects on AD. Calendula officinalis L. (Asteraceae) is commonly used for treating skin rashes and wounds.. In the present study, a three-herbs formula including Cortex Moutan and Herba Menthae, together with C. officinalis at 1:1:1 weight ratio was used as a topical agent and its therapeutic effects on AD was investigated.. In vitro effects of individual herbs and three-herbs formula (0.125-1 mg/ml) were examined using cytokine release assay on human mast HMC-1 cells, inflammation test on murine macrophage RAW cells and human keratinocyte (HaCaT) cells, and migration scratch assay on human umbilical vein endothelial cells (HUVEC). The contributing functional pathway of three-herbs formula in AD was explored using Western Blot assay in HMC-1 cells. Oxazolone-induced AD-like mice model was also used to investigate the in vivo therapeutic effect of the topical application of the three-herbs formula.. Herba Menthae, Cortex Moutan, and three-herbs formula significantly reduced the production of IL-6 and tumor necrosis factor (TNF)-α in HMC-1 cells, inhibited the expression of IL-6, IL-8 and CCL2 in TNF-α/IFN-γ stimulated HaCaT cells, and suppressed the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells. Moreover, Herba Menthae and three-herbs formula significantly suppressed CCL2 and TNF-α production in LPS-induced RAW 264.7 cells. C. officinalis and three-herbs formula promoted wound healing in HUVEC. For intracellular mechanisms, three-herbs formula inhibited the expressions of molecules in STAT1 and STAT3-dependent pathways. In vivo model showed that topical application of three-herbs formula on challenged ear reduced ear swelling and mice scratching frequencies. H&E and toluidine blue staining of the challenged ear tissue demonstrated that three-herbs formula reduced the epidermal thickness and mast cell infiltration, respectively.. The three-herbs formula of Cortex Moutan, Herba Menthae and C. officinalis at 1:1:1 (w/w) exhibited anti-inflammatory effect and promotion of cell migration in vitro. It also alleviated ear redness, swelling, epidermal thickness and inflammation of the OXA-induced AD mice. These findings suggest a potential beneficial role of the topical application of the three-herbs formula for treatment of AD.

Topics: Animals; Cytokines; Dermatitis, Atopic; HaCaT Cells; Human Umbilical Vein Endothelial Cells; Humans; Mice; Mice, Inbred BALB C; Oxazolone; Plant Preparations; RAW 264.7 Cells; Skin

Whereas atopic dermatitis (AD) is considered as a T helper 2 (Th2)-centered disease, IL-17-producing Th (Th17) cells are also activated in AD lesional skin. However, the relationship between Th17 responses and Th2 responses in AD is still to be elucidated. Although Th17 cells are increased in AD skin, the expression and function of IL-26, which is also produced by Th17 cells, in AD are still unknown. In this report, we demonstrated that IL-26 mRNA expression levels were elevated in AD lesional skin compared with healthy controls and that IL-26-producing cells were increased in AD lesional skin by immunohistochemistry. Furthermore, IL-26 promoted IL-8, IL-1β, chemokine (C-C motif) ligand 20, IL-33, and β-defensin 2 production in keratinocytes through phosphorylation of signal transducer and activator of transcription 1 and signal transducer and activator of transcription 3. Selective JAK inhibitors for JAK1, JAK2, and tyrosine kinase 2 blocked IL-26-induced cytokine production in keratinocytes. We also showed that injection of IL-26 exacerbated an oxazolone-induced AD mouse model and upregulated Th2 and Th17 cytokine expression in vivo. Because previous studies indicate that the above molecules induced by IL-26 can promote Th17 and/or Th2 immune responses, IL-26 may play an important role for bridging between Th17 and Th2 responses, resulting in the development of AD.

Topics: Adult; Animals; Biopsy; Case-Control Studies; Cell Line; Dermatitis, Atopic; Disease Models, Animal; Female; Healthy Volunteers; Humans; Interleukins; Janus Kinase Inhibitors; Keratinocytes; Male; Mice; Middle Aged; Oxazolone; Phosphorylation; Recombinant Proteins; RNA, Messenger; Severity of Illness Index; Signal Transduction; Skin; Th17 Cells; Th2 Cells; Young Adult

IL-13 and IL-4 are potent mediators of type 2-associated inflammation such as those found in atopic dermatitis (AD). IL-4 shares overlapping biological functions with IL-13, a finding that is mainly explained by their ability to signal via the type 2 IL-4 receptor (R), which is composed of IL-4Rα in association with IL-13Rα1. Nonetheless, the role of the type 2 IL-4R in AD remains to be clearly defined. Induction of two distinct models of experimental AD in

Topics: Animals; Dermatitis, Atopic; Dinitrofluorobenzene; Female; Interleukin-13; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Oxazolone; Receptors, Interleukin-4, Type II; Signal Transduction

Atopic dermatitis (AD) is a chronic inflammatory disease of the skin, characterized by dryness and more or less severe itching. The etiology of AD is complex and has not been fully clarified, involving genetic susceptibility, immunological abnormalities, epidermal barrier dysfunction, and environmental factors. Xyloglucan (XG) and pea protein (PP) are two compounds of natural origin characterized by the ability to create a physical barrier that protects mucosae membranes, reducing inflammation. The aim of the present study was to evaluate the potential beneficial effects of XG + PP in both a mouse model of AD and

Topics: Animals; Cell Degranulation; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Erythema; Female; Filaggrin Proteins; Glucans; Inflammation; Intermediate Filament Proteins; Mast Cells; Mice; Nitric Oxide Synthase Type II; Occludin; Oxazolone; Pea Proteins; Skin; Staphylococcal Infections; Staphylococcus aureus; Tight Junctions; Xylans

This study aimed to investigate the therapeutic effect of HP-NAP in AD mice model.. The model of AD was built with oxazolone (OXA) in BALB/c mice, then HP-NAP was used to treat AD by intraperitoneal injection. Ear thickness was measured by a digital thickness gauge. The ears tissues were collected and subjected to hematoxylin-eosin (H&E) and toluidine blue (TB) staining. The mRNA expression levels of inflammatory cytokines (IL-1β, IL-5, IL-6, and TNF-α) in ear tissue were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The secretion of IgE, IL-4, and IFN-γ was measured by enzyme-linked immunosorbent assay (ELISA).. Treatment with HP-NAP successfully alleviated the symptoms of AD, such as erythema, horny substance, and swelling. The infiltration of lymphocytes and mast cells were significantly reduced following HP-NAP therapy. The secretion of IgE and IL-4 was significantly attenuated following treatment with HP-NAP. Additionally, HP-NAP observably downregulated inflammatory cytokine expression (e.g. IL-1β, IL-5, IL-6, and TNF-α) in ear tissues.. Taken together, our results showed that HP-NAP possessed the potential to be a novel immunomodulatory candidate drug against AD.

Topics: Animals; Bacterial Proteins; Chemotaxis, Leukocyte; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Female; Immunoglobulin E; Immunologic Factors; Inflammation Mediators; Mast Cells; Mice, Inbred BALB C; Oxazolone; Skin; Th1-Th2 Balance

Glucocorticoids (GCs) are potent anti-inflammatory drugs, the secretion of which is mediated and controlled by the hypothalamic-pituitary-adrenal axis. However, they are also secreted de novo by peripheral tissues for local use. Several tissues express 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1), including the skin. The inactive GC cortisone is converted by 11β-HSD1 to active GC cortisol, which is responsible for delayed wound healing during a systemic excess of GC. However, the role of 11β-HSD1 in inflammation is unclear. We assessed whether 11β-HSD1 affects the development of atopic dermatitis (AD) in vitro and in vivo. The expression of 11β-HSD1 in the epidermis of AD lesions was higher than that in the epidermis of healthy controls. Knockdown of 11β-HSD1 in human epidermal keratinocytes increased the production of thymic stromal lymphopoietin. In an oxazolone-induced mouse model of AD, localized inhibition of 11β-HSD1 aggravated the development of AD and increased serum cytokine levels associated with AD. Mice with whole-body knockout (KO) of 11β-HSD1 developed significantly worse AD upon induction by oxazolone. We propose that 11β-HSD1 is a major factor affecting AD pathophysiology via suppression of atopic inflammation due to the modulation of active GC in the skin.

Topics: 11-beta-Hydroxysteroid Dehydrogenase Type 1; Animals; Case-Control Studies; Cell Line; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Epidermis; Female; Gene Knockout Techniques; Humans; Keratinocytes; Mice; Oxazolone; Thymus Gland; Up-Regulation

Atopic dermatitis is a chronic eczema commonly observed among children in Western countries. The gut microbiota is a significant factor in the pathogenesis, and ways to promote intestinal colonizers with anti-inflammatory capabilities are therefore favorable. The present study addressed the effects of a prebiotic, xylooligosaccharide (XOS), on the gut microbiota and ear inflammation in an oxazolone-induced dermatitis model in BALB/c mice. Mice were fed a XOS supplemented or a control diet throughout the experiment. Ear thickness and clinical skin inflammation were scored blindly after three weeks topical challenge with 0.4% oxazolone. The mice were divided into high and low responders to oxazolone-induced dermatitis based on clinical inflammation and histological evaluation of ear biopsies, and significantly fewer high responders were present in the XOS fed group. In addition, XOS fed mice had higher abundance of Prevotella spp. in their gut microbiota compared to the control fed mice. Serum IgE and ear tissue cytokine levels correlated significantly with the clinical scores, and with the abundance of Prevotella spp. The strong association between the low-responding phenotype and high abundance of Prevotella spp., indicates an alleviating effect of this intestinal colonizer in allergic sensitization. Prevotella should be considered as a relevant target for future microbiota-directed treatment strategies in atopic patients.

Topics: Animals; Dermatitis, Atopic; Dietary Supplements; Disease Models, Animal; Ear; Female; Gastrointestinal Microbiome; Immunoglobulin E; Mice; Mice, Inbred BALB C; Oxazolone; Prebiotics; Prevotella

To investigate the potential effects of acorn shells on atopic dermatitis (AD), we utilized oxazolone (OX)- or 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesion mouse models. Our research demonstrates that Acorn shell extract (ASE) improved the progression of AD-like lesions, including swelling, which were induced by oxazolone on Balb/c mouse ears. Additionally, ASE significantly decreased the ear thickness (OX: 0.42 ± 0.01 mm, OX-ASE: 0.32 ± 0.02 mm) and epidermal thickness (OX: 75.3 ± 32.6 µm, OX-ASE: 46.1 ± 13.4 µm). The continuous DNCB-induced AD mouse model in SKH-1 hairless mice demonstrated that ASE improved AD-like symptoms, including the recovery of skin barrier dysfunction, Immunoglobulin E hyperproduction (DNCB: 340.1 ± 66.8 ng/mL, DNCB-ASE: 234.8 ± 32.9 ng/mL) and an increase in epidermal thickness (DNCB: 96.4 ± 21.9 µm, DNCB-ASE: 52.4 ± 16.3 µm). In addition, we found that ASE suppressed the levels of AD-involved cytokines, such as Tumor Necrosis Factor α, IL-1β, IL-25 and IL-33 in both animal models. Furthermore, gallic acid and ellagic acid isolated from ASE suppressed β-hexosaminidase release and IL-4 expression in RBL-2H3 cells. The acorn shell and its active phytochemicals have potential as a new remedy for the improvement of atopic dermatitis and other inflammatory diseases.

Topics: Animals; Anti-Inflammatory Agents; Cell Line, Tumor; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Disease Models, Animal; Female; Mice; Mice, Hairless; Mice, Inbred BALB C; Oxazolone; Phytochemicals; Plant Extracts; Quercus; Rats

This study is aimed to further investigate the anti-atopic dermatitis (AD) activities of dehydroxymethylepoxyquinomicin (DHMEQ) ointment and compare its effect with that of tacrolimus ointment based on the previous study that DHMEQ improves AD-like lesions. AD were induced by 2,4-dinitroclilorobenzene/oxazolone (DNCB/OX) repeatedly on the ears of BABL/C mice while medical tape was additionally used to disrupt stratum corneum in order to exacerbate the lesions. The mice were randomly divided into groups, which are normal, vehicle, DHMEQ (0.1%) and tacrolimus (0.1%). Those in the last two groups were externally applied with DHMEQ ointment and tacrolimus ointment, respectively. The results showed that both of them significantly improved dermatitis symptoms of DNCB/OX-induced AD-like lesions, such as redness, itching, weeping, scaling and thickening of the skin, while reducing epidermis thickness, dermis thickness and the number of mast cells as well, which were examined histopathologically. In contrast with DHMEQ, tacrolimus led to a significant decrease in body weight after long-term application. Both DHMEQ and tacrolimus suppress DNCB-induced increase of serum total IgE and attenuate expression of inflammatory factors IL-4, IL-6, IL-13, IL-1β and interferon (IFN)-γ in the disrupted ear tissues. On the other hand, the mice applied with tacrolimus became obviously irritable, jumping up and down, and inflammatory exudation on the lesioned-skin surface of the mice was remarkably observed. Contrary to the side effects made by tacrolimus, DHMEQ didn't cause any adverse stimulus response. As a conclusion, DHMEQ is safer, milder and more suitable for long-term use than tacrolimus for the treatment of AD-like lesions.

Topics: Animals; Benzamides; Cyclohexanones; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Disease Models, Animal; Epidermis; Female; Humans; Immunoglobulin E; Immunosuppressive Agents; Inflammation Mediators; Mast Cells; Mice; Mice, Inbred BALB C; Ointments; Oxazolone; Tacrolimus

Atopic dermatitis is a common inflammatory skin disease caused by the interaction of genetic and environmental factors. By allelic copy number analysis at missense single-nucleotide polymorphisms on 26 genes with copy number variation, we identified a significant association between atopic dermatitis and human KPRP. Human KPRP expression, which was localized to the upper granular layer of epidermis, was significantly decreased in atopic dermatitis compared with normal skin. KPRP was histologically colocalized with loricrin and was mainly detected in cytoskeleton fractions of human keratinocytes. To further investigate the role of KPRP in skin, Kprp-knockout mice were generated. Heterozygous knockout (Kprp

Topics: Adjuvants, Immunologic; Animals; Case-Control Studies; Croton Oil; Cytoskeletal Proteins; Dermatitis, Atopic; Desmosomes; Disease Models, Animal; DNA Copy Number Variations; Epidermis; Humans; Intracellular Signaling Peptides and Proteins; Keratinocytes; Mice; Mice, Knockout; Microscopy, Electron, Transmission; Oxazolone; Proteins; Water Loss, Insensible

Skin acts as a barrier, which protects internal tissues and promotes moisture retention. Atopic dermatitis (AD) is an inflammatory skin disease associated with a variety of genetic and environmental factors that involve helper T cells. β-Carotene (provitamin A) exhibits antioxidant activity and activates the immune system. However, it is not clear whether inflammation in AD skin is improved by posttreatment with β-carotene. In the current study, we investigated the effects of β-carotene on the skin of hairless mice with oxazolone-induced inflammation/oedema (Ox-AD mice). We found that skin inflammation was significantly reduced by oral administration of β-carotene. In addition, treatment with β-carotene suppressed protein levels of TNF-α, IL-1β and MCP-1, as well as mRNA expression associated with IL-1β, IL-6, IL-4 and Par-2 in skin tissues. Furthermore, the mRNA and protein levels of filaggrin, a structural protein in the epidermal stratum corneum, were elevated by β-carotene administration as compared with Ox-AD mice. β-Carotene significantly reduced the activity of proMMP-9, but not proMMP-2. These results suggest that in Ox-AD mice, β-carotene improves skin inflammation by suppressing the expression of inflammatory factors, promoting filaggrin expression and reducing MMP-9 activity. β-Carotene is a potent anti-inflammatory agent that improves the barrier functions of AD skin.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; beta Carotene; Cytokines; Dermatitis, Atopic; Enzyme Precursors; Filaggrin Proteins; Gene Expression Regulation; Inflammation Mediators; Intermediate Filament Proteins; Matrix Metalloproteinase 9; Mice; Mice, Hairless; Oxazolone; RNA, Messenger; Skin; Specific Pathogen-Free Organisms

The fruits of Juniperus rigida have been used in Korean traditional medicine for the treatment of inflammatory diseases in humans such as rheumatoid arthritis.. This study aimed to investigate the anti-atopic properties of J. rigida fruit in in vivo murine atopic dermatitis (AD) models.. BALB/c mouse ears ad SKH-1 hairless mice stimulated with oxazolone (4 weeks) and DNCB (3 weeks), respectively, were treated with the 1% Juniperus rigida fruit EtOH extract (JFE). The JFE improved AD symptoms in both oxazolone- and DNCB-induced AD mice by accelerating skin barrier recovery function and suppressing the overproduction of serum immunoglobulin E (IgE) and interleukin 4 (IL-4). The JFE was found to contain isoscutellarein-7-O-β-xylopyranoside, cupressuflavone, podocarpusflavone A, and hinokiflavone as major components based on phytochemical analysis. Eight flavonoids were isolated from JFE, and of those, cupressuflavone and isoscutellarein-7-O-β-xylopyranoside strongly down-regulated IL-4 expression and β-hexosaminidase release in RBL-2H3 cells.. Therapeutic attempts with J. rigida fruit and its active components might be useful in treating AD and related skin inflammatory diseases.

Topics: Animals; Anti-Inflammatory Agents; beta-N-Acetylhexosaminidases; Cell Line, Tumor; Dermatitis, Atopic; Dinitrochlorobenzene; Disease Models, Animal; Female; Fruit; Immunoglobulin E; Interleukin-4; Juniperus; Mice, Hairless; Mice, Inbred BALB C; Oxazolone; Phytotherapy; Plant Extracts; Plants, Medicinal; Rats; Skin

Eupatilin (5,7-dihydroxy-3',4',6-trimethoxyflavone) is the main lipophilic flavonoid obtained from the Artemisia species. Eupatilin has been reported to have anti-apoptotic, anti-oxidative and anti-inflammatory activities. Previously, we found that eupatilin increases transcriptional activity and expression of peroxisome proliferator-activated receptor α (PPARα) in a keratinocyte cell line and acts as an agonist of PPARα. PPARα agonists ameliorate atopic dermatitis (AD) and restore the skin barrier function. In this study, we confirmed that the effects of eupatilin improved AD-like symptoms in an oxazolone-induced AD-like mouse model. Furthermore, we found that eupatilin suppressed the levels of serum immunoglobulin E (IgE), interleukin-4 (IL-4), and AD involved cytokines, such as tumor necrosis factor α (TNFα), interferon-γ (IFN-γ), IL-1β, and thymic stromal lymphopoietin (TSLP), IL-33, IL-25 and increased the levels of filaggrin and loricrin in the oxazolone-induced AD-like mouse model. Taken together, our data suggest that eupatilin is a potential candidate for the treatment of AD.

Topics: Animals; Cell Line, Tumor; Cytokines; Dermatitis, Atopic; Dermatologic Agents; Dose-Response Relationship, Drug; Drugs, Chinese Herbal; Female; Filaggrin Proteins; Flavonoids; Gene Expression Regulation; Immunoglobulin E; Interferon-gamma; Interleukin-1beta; Interleukin-33; Interleukin-4; Interleukins; Intermediate Filament Proteins; Membrane Proteins; Mice; Mice, Inbred BALB C; Oxazolone; PPAR alpha; Rats; Signal Transduction; Thymic Stromal Lymphopoietin; Tumor Necrosis Factor-alpha

Juniperus chinensis, commonly Chinese juniper, has been used for treating inflammatory diseases. This study aimed to investigate anti-atopic dermatitis (AD) effects of standardized J. chinensis fruits extract on murine oxazolone- and 2,4-dinitrochlorobenzene (DNCB)-induced models of AD. Ear swelling, epidermis thickening, and eosinophils infiltration in the oxazolone-mediated dermatitis of BALB/c mice were significantly reduced upon topical application of J. chinensis fruits 95% EtOH extract (JCE). Besides, transdermal administration of JCE to SKH-1 hairless mice inhibited the development of DNCB-induced AD-like skin lesions by suppressing transepidermal water loss and improving skin hydration. Decreased total serum immunoglobulin E (IgE) and interleukin (IL)-4 levels could be observed in atopic dorsal skin samples of JCE-treated group. According to the phytochemical analysis, JCE was found to contain isoscutellarein-7-O-β-D-xyloside, cupressuflavone, and amentoflavone as main compounds. Therapeutic attempts with the J. chinensis fruits might be useful in the treatment of AD and related skin inflammatory diseases.

Topics: Adjuvants, Immunologic; Administration, Cutaneous; Animals; Anti-Inflammatory Agents, Non-Steroidal; Biflavonoids; Dermatitis, Atopic; Dinitrochlorobenzene; Female; Flavonoids; Fruit; Glycosides; Immunoglobulin E; Interleukin-4; Irritants; Juniperus; Mice, Hairless; Mice, Inbred BALB C; Molecular Structure; Oxazolone; Phytotherapy; Plant Extracts; Republic of Korea; Skin

Atopic dermatitis is a common skin disease characterized by a Th2 cell-dominant inflammatory infiltrate, elevated serum IgE levels and impaired epidermal barrier function. It is associated to abnormal epidermal lamellar body secretion, producing alteration in lipid composition and extracellular lamellar membrane organization.. The oxazolone-induced atopic dermatitis in hairless mice was used to evaluate in vivo the effect of the application of a lipid system that mimics the morphology, structure and composition of epidermal lamellar bodies.. The skin barrier function was evaluated measuring TEWL and skin hydration in vivo. Inflammation was assessed by analysis of serum IgE levels and histological analysis. The microstructure of the intercellular lipid region was also evaluated before and after treatment.. The skin condition was improved after 10 days of treatment indicated by decreased TEWL, decreased serum IgE levels, reduced epidermal thickness and reduced lymphocyte-dominated infiltrate. However, the treatment did no improve skin hydration.. The treatment with this lipid system seems to improve the skin condition by reinforcing the barrier function and reducing the skin inflammation. Therefore, the present study provides evidence that this lipid system combining appropriate lipid composition and morphology could be of interest for the development of future treatments for atopic dermatitis.

Topics: Administration, Cutaneous; Animals; Biomimetic Materials; Biopsy; Dermatitis, Atopic; Disease Models, Animal; Epidermis; Female; Humans; Immunoglobulin E; Lipids; Mice; Mice, Hairless; Microscopy, Electron, Transmission; Oxazolone; Water Loss, Insensible

Dehydroxymethylepoxyquinomicin (DHMEQ) which is originally developed as an analog of antibiotic epoxyquinomicin C is a specific and potent inhibitor of NF-κB and has been shown to possess promising potential as an anti-inflammatory and anti-tumor agent.. This study examines DHMEQ's effect on therapeutic potential for atopic dermatitis (AD)-like lesions.. AD lesions were chronically induced by the repetitive and alternative application of 2,4-dinitrochlorobenzene (DNCB) and oxazolone (OX) on ears in BALB/c mice. The mice were then externally treated with DHMEQ ointment. Macroscopic and microscopic changes of the skin lesions were observed and recorded.. DHMEQ inhibited ear swelling and relieved clinical symptoms of the AD-like lesions induced by DNCB/OX in BALB/c mice. Histopathology examination illustrated that it significantly decreased DNCB/OX-induced epidermal thickness, the infiltration of inflammatory cells, and the count of mast cell. The elevated level of immunoglobulin E (IgE) in serum and the mRNA levels of interferon γ (IFN-γ), interleukin 4 (IL-4) and IL-13 in the ear tissues, were also suppressed by DHMEQ.. This study indicated that DHMEQ would be useful for the treatment of AD.

Topics: Animals; Benzamides; Cyclohexanones; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Epidermis; Mice; Mice, Inbred BALB C; NF-kappa B; Ointments; Oxazolone

Atopic dermatitis (AD) is a chronically relapsing inflammatory skin disease characterized by hyperproliferation and abnormal differentiation of the epidermis, and dermal infiltration of inflammatory cells. Appropriate animal models that recapitulate human AD and allow the analysis of disease processes in a reliable manner are essential to the study of AD. In this study, we established two AD models in rabbits by applying an allergen, Dermatophagoides farinae (Der f), or a hapten, oxazolone (OXZ). Application of the allergen or hapten induced a rapid onset and a chronically sustained AD-like skin lesion. The clinical symptoms, which include skin erythema, scaling, papula and edema, of AD-like rabbit skin were similar to those in human AD. Histological analysis showed that allergen- or hapten-treated rabbit skin showed increased epidermal thickening and inflammatory cell infiltration. Furthermore, PCNA and keratin 10 (K10) staining revealed excessive proliferation and insufficient differentiation of the epidermis in the rabbit AD-like skin. Western blot analysis showed decreased expression of thymic stromal lymphopoietin (TSLP), an AD cytokine, in the rabbit AD-like skin. Our results suggest that the allergen- or hapten-induced rabbit AD models have pathological features of human AD-like symptoms and will be useful for evaluating both pathogenic mechanisms and potential therapeutic agents for human AD.

Topics: Allergens; Animals; Cell Proliferation; Cytokines; Dermatitis, Atopic; Dermatophagoides farinae; Disease Models, Animal; Edema; Epidermis; Erythema; Female; Oxazolone; Rabbits; Thymic Stromal Lymphopoietin

Atopic Dermatitis (AD) has been associated with gut microbiota (GM) dysbiosis in humans, indicating a causative role of GM in AD etiology. Furthermore, the GM strongly correlates to essential disease parameters in the well-known oxazolone-induced mouse model of AD. Here, we demonstrate that it is possible to transfer both a high-responding and a low-responding AD phenotype with GM from conventional mice to germ-free mice. The mice inoculated with the high-responding GM had significantly higher clinical score, increased ear thickness, and increased levels of IL-1β, TNFα, IL-4, IL-5, and IL-6 compared to the mice inoculated with the low-responding GM. The inter-individual variation was in general not affected by this increase in effect size. Germ-free mice induced with AD revealed a high disease response as well as high inter-individual variation indicating protective properties of certain microbial taxa in this model. This study underlines that the GM has a strong impact on AD in mouse models, and that the power of studies may be increased by the application of mice inoculated with a specific GM from high responders to increase the effect size.

Topics: Animals; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Dysbiosis; Gastrointestinal Microbiome; Humans; Mice; Oxazolone; Tumor Necrosis Factor-alpha

Topics: Animals; Dermatitis, Atopic; Disaccharides; Disease Models, Animal; Drug Therapy, Combination; Epidermis; Immunoglobulins; Mice; Mice, Inbred Strains; Oxazolone; Random Allocation; Receptor, PAR-2; Receptors, Cytokine; Treatment Outcome

Atopic dermatitis (AD) is a common allergic skin disease, characterized by dryness, itchiness, thickening and inflammation of the skin. Infiltration of eosinophils into the dermal layer and presence of edema are typical characteristics in the skin biopsy of AD patients. Previous in vitro and clinical studies showed that the Pentaherbs formula (PHF) consisting of five traditional Chinese herbal medicines, Flos Lonicerae, Herba Menthae, Cortex Phellodendri, Cortex Moutan and Rhizoma Atractylodis at w/w ratio of 2:1:2:2:2 exhibited therapeutic potential in treating AD. In this study, an in vivo murine model with oxazolone (OXA)-mediated dermatitis was used to elucidate the efficacy of PHF. Active ingredients of PHF water extract were also identified and quantified, and their in vitro anti-inflammatory activities on pruritogenic cytokine IL-31- and alarmin IL-33-activated human eosinophils and dermal fibroblasts were evaluated. Ear swelling, epidermis thickening and eosinophils infiltration in epidermal and dermal layers, and the release of serum IL-12 of the murine OXA-mediated dermatitis were significantly reduced upon oral or topical treatment with PHF (all p < 0.05). Gallic acid, chlorogenic acid and berberine contents (w/w) in PHF were found to be 0.479%, 1.201% and 0.022%, respectively. Gallic acid and chlorogenic acid could suppress the release of pro-inflammatory cytokine IL-6 and chemokine CCL7 and CXCL8, respectively, in IL-31- and IL-33-treated eosinophils-dermal fibroblasts co-culture; while berberine could suppress the release of IL-6, CXCL8, CCL2 and CCL7 in the eosinophil culture and eosinophils-dermal fibroblasts co-culture (all p < 0.05). These findings suggest that PHF can ameliorate allergic inflammation and attenuate the activation of eosinophils.

Topics: Animals; Anti-Inflammatory Agents; Berberine; Cells, Cultured; Chemokines; Chlorogenic Acid; Coculture Techniques; Dermatitis, Atopic; Disease Models, Animal; Drugs, Chinese Herbal; Eosinophils; Fibroblasts; Gallic Acid; Humans; Interleukin-12; Medicine, Chinese Traditional; Mice; Oxazolone

Impaired immune responses in skin play a pivotal role in the development and progression of chemical-associated inflammatory skin disorders. In this study, we synthesized new flavonoid derivatives from macakurzin C, and identified in vitro and in vivo efficacy of a potent anti-inflammatory flavonoid, Compound 14 (CPD 14), with its underlying mechanisms. In lipopolysaccharide (LPS)-stimulated murine macrophages and IFN-γ/TNF-α-stimulated human keratinocytes, CPD 14 significantly inhibited the release of inflammatory mediators including nitric oxide (NO), prostaglandins, and cytokines (IC50 for NO inhibition in macrophages: 4.61μM). Attenuated NF-κB signaling and activated Nrf2/HO-1 pathway were responsible for the anti-inflammatory effects of CPD 14. The in vivo relevance was examined in phorbol 12-myristate 13-acetate (TPA)-induced acute skin inflammation and oxazolone-induced atopic dermatitis models. Topically applied CPD 14 significantly protected both irritation- and sensitization-associated skin inflammation by suppressing the expression of inflammatory mediators. In summary, we demonstrated that a newly synthesized flavonoid, CPD 14, has potent inhibitory effects on skin inflammation, suggesting it is a potential therapeutic candidate to treat skin disorders associated with excessive inflammation.

Topics: Acute Disease; Animals; Anti-Inflammatory Agents; Cell Line; Chronic Disease; Dermatitis, Atopic; Dinoprostone; Flavonoids; Heme Oxygenase-1; Humans; Interferon-gamma; Lipopolysaccharides; Male; Mice; Mice, Inbred BALB C; Mice, Inbred ICR; NF-E2-Related Factor 2; NF-kappa B; Nitric Oxide; Oxazolone; RAW 264.7 Cells; Tetradecanoylphorbol Acetate; Tumor Necrosis Factor-alpha

Skin inflammation plays a central role in the pathophysiology and symptoms of diverse chronic skin diseases including atopic dermatitis (AD). In this study, we examined if caffeic acid phenethyl ester (CAPE), a skin-permeable bioactive compound from propolis, was protective against skin inflammation using in vitro cell system and in vivo animal disease models. CAPE suppressed TNF-α-induced NF-κB activation and expression of inflammatory cytokines in human keratinocytes (HaCaT). The potency and efficacy of CAPE were superior to those of a non-phenethyl derivative, caffeic acid. Consistently, topical treatment of CAPE (0.5 %) attenuated 12-O-tetradecanoylphorbol-13-acetate(TPA)-induced skin inflammation on mouse ear as CAPE reduced ear swelling and histologic inflammation scores. CAPE suppressed increased expression of pro-inflammatory molecules such as TNF-α, cyclooxygenase-2 and inducible NO synthase in TPA-stimulated skin. TPA-induced phosphorylation of IκB and ERK was blocked by CAPE suggesting that protective effects of CAPE on skin inflammation is attributed to inhibition of NF-κB activation. Most importantly, in an oxazolone-induced chronic dermatitis model, topical application of CAPE (0.5 and 1 %) was effective in alleviating AD-like symptoms such as increases of trans-epidermal water loss, skin thickening and serum IgE as well as histologic inflammation assessment. Collectively, our results propose CAPE as a promising candidate for a novel topical drug for skin inflammatory diseases.

Topics: Acute Disease; Animals; Caffeic Acids; Cell Line; Chronic Disease; Cyclooxygenase 2; Dermatitis, Atopic; Disease Models, Animal; Humans; Immunoglobulin E; Inflammation; Keratinocytes; Mice; Mice, Inbred Strains; NF-kappa B; Oxazolone; Phenylethyl Alcohol; Propolis; Skin; Tetradecanoylphorbol Acetate; Tumor Necrosis Factor-alpha; Water Loss, Insensible

Even with the widespread clinical use of cannabinoid receptor (CBR) stimulating compounds, such as palmitoylethanolamine, the role of CBR agonists on inflammatory skin diseases is not yet fully understood. This study was performed to investigate the effects of CBR agonists on skin inflammation, using acute and chronic inflammation animal models.. The effectiveness of the newly synthesized cannabinoid receptor 1 (CB1R) agonists was determined using in vitro assays. Markers for epidermal permeability barrier function and skin inflammation were measured, and histological assessments were performed for evaluation.. Topical application of CB1R-specific agonist significantly accelerated the recovery of epidermal permeability barrier function and showed anti-inflammatory activity in both acute and chronic inflammation models. Histological assessments also confirmed the anti-inflammatory effects, which is consistent with previous reports.. All of the results suggest that topical application of CB1R-specific agonist can be beneficial for alleviating the inflammatory symptoms in chronic skin diseases, including atopic dermatitis.

Topics: Acute Disease; Administration, Cutaneous; Animals; Cannabinoid Receptor Agonists; Chronic Disease; Dermatitis, Atopic; Dermatitis, Contact; Disease Models, Animal; Fatty Acids, Unsaturated; Female; Mice, Inbred BALB C; Oxazolone; Permeability; Propanolamines; Receptor, Cannabinoid, CB1; Skin; Skin Physiological Phenomena; Tetradecanoylphorbol Acetate; Water Loss, Insensible

Topical pseudoceramides are successfully used in skin barrier repair therapy for atopic dermatitis (AD) and demonstrated to reduce the adverse effects of topical glucocorticoids (GC). However, the molecular mechanisms involved are not fully understood. We investigated whether PC-9S (myristoyl/palmitoyloxostearamide/arachamide MEA, Neopharm, Daejeon, Korea), one of the synthetic pseudoceramides, could stimulate peroxisome proliferator-activated receptor (PPAR)α expression in a hapten [oxazolone (oxa)]-induced AD murine model (oxa-AD mice) and subsequently improved permeability barrier, reduced inflammation, and increased antimicrobial peptides (AMPs) expression. Normal hairless mice and oxa-AD mice were topically treated twice daily with either PC-9S-containing physiologic lipid mixture (PLM), vehicle (PLM), or PPARα agonist for 4 days. Topical PC-9S significantly increased PPARα expression in mouse epidermis in vivo and in oxa-AD mice skin comparable with PPARα agonist. Topical PC-9S-containing PLM significantly reduced basal trans-epidermal water loss (TEWL), surface pH, and mast cell infiltrates and prevented the decline of AMPs expression in oxa-AD mice, which were abrogated by PPARα antagonist. Then, oxa-AD mice were treated with super-potent topical GC twice daily for 4 days with or without PC-9S co-applications. Co-treatment with PC-9S-containing PLM suppressed GC-induced increase in basal TEWL, epidermal thinning, reduced loricrin expression, and impaired barrier recovery and these effects were attenuated by PPARα antagonist. Collectively, our findings suggest that pseudoceramide PC-9S-induced stimulation of PPARα expression provides a new mechanism by which pseudoceramides show anti-inflammatory property, improve the permeability and antimicrobial barrier function, and prevent the negative effects of topical GC.

Topics: Administration, Topical; Animals; Anti-Inflammatory Agents; Arachidonic Acids; Ceramides; Dermatitis, Atopic; Female; Glucocorticoids; Inflammation; Membrane Proteins; Mice; Mice, Hairless; Oxazolone; PPAR alpha; Skin; Stearic Acids; Tight Junctions

Panduratin A isolated from Boesenbergia pandurata (Roxb.) has been reported to have antioxidant, anti-inflammatory, and anti-allergic activities. However, the effect of panduratin A on atopic dermatitis (AD) has not been studied. In the present study, we investigated the efficacy of panduratin A, an activator of peroxisome proliferator-activated receptors (PPAR) α/δ, using oxazolone-induced AD-like model in hairless mice.. To determine PPARα/δ activation of panduratin A, HaCaT, Hs68, and COS-7 cells were treated with panduratin A, then PPARα/δ and PPAR response element (PPRE) activities were assessed with a reporter gene assay. For the in vivo study, oral administration of panduratin A was performed for 4weeks, with oxazolone treatment every other day. The efficacy of panduratin A on parameters of oxazolone-induced AD was assessed physiologically, morphologically, and immunologically.. Panduratin A increased PPARα/δ and PPRE activation both in vitro and in vivo. Panduratin A attenuated dermatitis-associated barrier damage as demonstrated by transepidermal water loss, erythema, and filaggrin expression. Furthermore, infiltration of inflammatory cells and epidermal thickness in the skin were decreased. Panduratin A decreased serum immunoglobulin (Ig) E and interleukin-4 levels but increased IgG2a and interferon-γ levels. In addition, panduratin A decreased inflammation-associated molecules in the skin. Panduratin A also decreased Th2-associated molecules and increased Th1/regulatory T cell (Treg)-associated molecules in the spleen.. Panduratin A showed a beneficial effect on AD by modulating Th1/Th2/Treg-associated immune response and is a potential candidate for treating AD.

Topics: Animals; Chalcones; Chlorocebus aethiops; COS Cells; Cytokines; Dermatitis, Atopic; Drug Evaluation, Preclinical; Female; Filaggrin Proteins; Genes, Reporter; Humans; Immunoglobulin E; Immunoglobulin G; Mice; Mice, Hairless; Oxazolone; PPAR alpha; PPAR delta; Skin; T-Lymphocyte Subsets; Transcriptional Activation

Levocetirizine, an active enantiomer of cetirizine is third generation antihistaminic agent used for treating various allergies like atopic dermatitis, chronic idiopathic urticaria and allergic rhinitis.. Development of novel topical formulation of levocetirizine based on flexible vesicles (FVs) with an aim to have targeted peripheral antihistaminic effect.. The FVs were prepared by thin film hydration method and characterized for drug content, entrapment efficiency, pH, vesicular size, spreadability, morphological characteristics and drug leakage studies. Franz diffusion cell assembly was used to carry out the ex vivo permeation studies through mice skin and the permeation profile of the developed FV formulation was compared with conventional formulations of levocetirizine.. The ex vivo permeation studies revealed 1.78-fold increase in percent permeation of levocetirizine from FV formulation as compared to conventional formulations of levocetirizine in 8 h. Further, oxazolone induced atopic dermatitis murine model was selected to study the in vivo pharmacodynamic activity. The developed formulation was evaluated for scratching score, erythema score and histological evaluation. There was marked reduction in scratching score from 15.25 scratches/20 min with conventional levocetirizine cream to 6.75 scratches/20 min with application of levocetirizine FV formulation. Also, there was significant reduction in erythema score as well as dermal eosinophil count. Results of skin sensitivity and toxicity studies suggest that the developed formulation was dermally safe and nontoxic.. A novel FVs based topical formulation of levocetirizine was successfully developed for treatment of atopic dermatitis.

Topics: Administration, Cutaneous; Animals; Cetirizine; Chemistry, Pharmaceutical; Dermatitis, Atopic; Elasticity; Female; Liposomes; Mice, Inbred BALB C; Oxazolone; Skin

Long-standing or repeated skin barrier damage followed by atopic dermatitis (AD) is the initial step of the atopic march that eventually progresses to respiratory allergies. Maintenance of an acidic pH in the stratum corneum (SC) is an important factor for normal skin barrier function. We performed this study to determine whether an oxazolone (Ox)-induced AD murine model can develop airway inflammation by topical application and nasal inhalation of a house dust mite, Dermatofagoides pteronyssinus (Dp), which is a novel 'atopic march animal model', and whether an acidic SC environment, made by repeated application of acidic cream, can interrupt this atopic march. During repeated treatment with Ox and Dp to make an atopic march murine model, acidic cream (pH 2.8) and neutral cream (pH 7.4) adjusted by citric acid and sodium hydroxide mixed with vehicle were applied twice daily. Repeated treatment with Ox and Dp to hairless mice induced AD-like skin lesions followed by respiratory allergy, defining it as an atopic march model. Acidic cream inhibited the occurrence of respiratory allergic inflammation as well as AD-like skin lesions. These results indicate that a novel atopic march animal model can be developed by repeated topical and nasal treatments with house dust mite on Ox-induced AD mice and that the acidification of SC could be a novel intervention method to block the atopic march.

Topics: Administration, Inhalation; Administration, Topical; Allergens; Animals; Antigens, Dermatophagoides; Asthma; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Female; Hydrogen-Ion Concentration; Immunoglobulin E; Mice; Mice, Hairless; Oxazolone; Skin Cream; Thymic Stromal Lymphopoietin

Oxazolone-induced colitis in mice has become a recognized model to study the efficacy of therapeutics targeting the immunological response underlying the development of inflammatory bowel disease. However, this model cannot be used when therapeutics designed to address human targets do not interact with the respective murine counterpart. In this study, we examined the induction of oxazolone mediated colitis in non-obese diabetic-severe combined immunodeficiency interleukin-2Rγ(null) (NOD-SCID IL2Rγ(null)) mice engrafted with human peripheral blood mononuclear cells (hPBMC) derived from patients suffering from ulcerative colitis (UC), atopic dermatitis (AD) and healthy volunteers. NOD-SCID IL2Rγ (null) mice were engrafted with hPBMC followed by challenge with oxazolone or ethanol vehicle. Mice developed the same symptoms as observed previously in immunocompetent mice. The clinical activity score increased and the colon architecture was characterized by the development of oedema, fibrosis, crypt loss and dense infiltration of predominantly T cells into the lamina propria. Fluorescence activated cell sorter (FACS) analysis of lymphocytes in the colon identified natural killer (NK) T cells as a major constituent. In contrast to studies with immunocompetent mice, we observed the same phenotype in the group challenged with ethanol vehicle. The phenotype was most pronounced in mice engrafted with PBMC derived from a patient suffering from UC, suggesting that the immunological history of the donors predisposes the engrafted mice to react to ethanol. The model described here has the potential to study the efficacy of therapeutics targeting human lymphocytes in a model which is more reflective of the human disease. In addition, it might be developed to elucidate molecular mechanisms underlying the disease.

Topics: Animals; Cell Line; Colitis, Ulcerative; Dermatitis, Atopic; Disease Models, Animal; Ethanol; Graft vs Host Disease; Humans; Immunoglobulin E; Immunoglobulin G; Interleukin Receptor Common gamma Subunit; Leukocytes, Mononuclear; Mice; Mice, Inbred BALB C; Mice, Inbred NOD; Mice, SCID; Mice, Transgenic; Oxazolone; Receptors, Interleukin-2; Transplantation, Heterologous

Atopic dermatitis (AD) is a refractory and recurrent inflammatory skin disease. Various factors including heredity, environmental agent, innate and acquired immunity, and skin barrier function participate in the pathogenesis of AD. T -helper (Th) 2-dominant immunological milieu has been suggested in the acute phase of AD. Antigen 85B (Ag85B) is a 30-kDa secretory protein well conserved in Mycobacterium species. Ag85B has strong Th1-type cytokine inducing activity, and is expected to ameliorate Th2 condition in allergic disease. To perform Ag85B function in vivo, effective and less invasive vaccination method is required. Recently, we have established a novel functional virus vector; recombinant human parainfluenza type 2 virus vector (rhPIV2): highly expressive, replication-deficient, and very low-pathogenic vector. In this study, we investigated the efficacy of rhPIV2 engineered to express Ag85B (rhPIV2/Ag85B) in a mouse AD model induced by repeated oxazolone (OX) challenge. Ear swelling, dermal cell infiltrations and serum IgE level were significantly suppressed in the rhPIV2/Ag85B treated mouse group accompanied with elevated IFN-γ and IL-10 mRNA expressions, and suppressed IL-4, TNF-α and MIP-2 mRNA expressions. The treated mice showed no clinical symptom of croup or systemic adverse reactions. The respiratory tract epithelium captured rhPIV2 effectively without remarkable cytotoxic effects. These results suggested that rhPIV2/Ag85B might be a potent therapeutic tool to control allergic disorders.

Topics: Animals; Antigens, Bacterial; Cell Line; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Gene Expression; Genetic Vectors; Humans; Immunoglobulin E; Male; Mice; Oxazolone; Parainfluenza Virus 2, Human; RNA, Messenger; Skin; T-Lymphocytes, Regulatory; Vaccines, DNA

Animal models mimicking human diseases have been used extensively to study the pathogenesis of autoimmune diseases and the efficacy of potential therapeutics. They are, however, limited with regard to their similarity to the human disease and cannot be used if the antagonist and its cognate receptor require high similarity in structure or binding. Here, we examine the induction of oxazolone-mediated features of atopic dermatitis (AD) in NOD-scid IL2Rγ(null) mice engrafted with human peripheral blood mononuclear cells (PBMC). The mice developed the same symptoms as immunocompetent BALB/c mice. Histological alterations induced by oxazolone were characterized by keratosis, epithelial hyperplasia and influx of inflammatory cells into the dermis and epidermis. The cellular infiltrate was identified as human leukocytes, with T cells being the major constituent. In addition, oxazolone increased human serum IgE levels. The response, however, required the engraftment of PBMC derived from patients suffering from AD, which suggests that this model reflects the immunological status of the donor. Taken together, the model described here has the potential to evaluate the efficacy of therapeutics targeting human lymphocytes in vivo and, in addition, might be developed further to elucidate molecular mechanisms inducing and sustaining flares of the disease.

Topics: Adjuvants, Immunologic; Animals; CD4-CD8 Ratio; Dermatitis, Atopic; Disease Models, Animal; Humans; Immunoglobulin E; Immunoglobulin G; Interleukin Receptor Common gamma Subunit; Leukocytes, Mononuclear; Mice; Mice, Inbred BALB C; Mice, Inbred NOD; Mice, Knockout; Mice, SCID; Oxazolone; Skin; Transplantation, Heterologous

The development of chronic allergic dermatitis in early life has been associated with increased onset and severity of allergic asthma later in life. However, the mechanisms linking these two diseases are poorly understood. In this study, we report that the development of oxazolone-induced chronic allergic dermatitis, in a mouse model, caused enhanced OVA-induced allergic asthma after the resolution of the former disease. Our findings show that oxazolone-induced dermatitis caused a marked increase in tissue mast cells, which persisted long after the resolution of this disease. Subsequent OVA sensitization and airway challenge of mice that had recovered from dermatitis resulted in increased allergic airway hyperreactivity. The findings demonstrate that the accumulation of mast cells during dermatitis has the detrimental effect of increasing allergic airway hypersensitivity. Importantly, our findings also show that exposure to a given allergen can modify the immune response to an unrelated allergen.

Topics: Animals; Bronchial Hyperreactivity; Cell Count; Chronic Disease; Dermatitis, Atopic; Disease Models, Animal; Disease Progression; Mast Cells; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Transgenic; Ovalbumin; Oxazolone; Respiratory Hypersensitivity; Tissue Distribution

At present, laboratory animals are not standardized with regard to the gastrointestinal microbiota (GM), but differences in this feature may alter various parameters in animal models. We hypothesized that variation in the GM correlated with variation in clinical parameters of a murine oxazolone-induced skin inflammation model of atopic dermatitis. BALB/cA mice were sensitized with oxazolone over a 28-d period and variation in gastrointestinal microbiota in fecal and cecal samples was assessed by PCR-denaturing gradient gel electrophoresis. Clinical parameters included transepidermal water loss, ear thickness, inflammatory factors in ear tissue and plasma, and histopathologic evaluation. The fecal microbiota before induction of skin inflammation strongly correlated with the levels of some proinflammatory cytokines (IFNγ, IL1β, IL12, and TNFα), the antiinflammatory cytokines IL4 and IL10, and the chemokine KC/GRO that were measured in ear samples at study termination. Cecal microbiota at termination correlated with ear thickness and transepidermal water loss. There was no correlation between cytokine responses and ear thickness or transepidermal water loss. In addition, GM changed during the study period in the oxazolone-treated mice, whereas this was not the case for the control mice. The current study shows that the GM of mice influences the development of oxazolone-induced skin inflammation and that the model itself likely induces a pathophysiologic response that alters the composition of the GM.

Topics: Animals; Cecum; Cytokines; Denaturing Gradient Gel Electrophoresis; Dermatitis, Atopic; Ear; Feces; Female; Gastrointestinal Tract; Metagenome; Mice; Mice, Inbred BALB C; Oxazolone; Principal Component Analysis; Regression Analysis; Water Loss, Insensible

In the present study, we examined the inhibitive effect of ginsenoside Rh1 on oxazolone-induced atopic dermatitis-like skin lesions in hairless mice. Oral administration of ginsenoside Rh1 improved clinical symptoms, and it was confirmed by histophathological analysis. In ginsenoside Rh1 (20mg/kg) group, ear swellings and ear weights were significantly lower than the control group. Moreover, elevation of IL-6 and total IgE levels in serum were suppressed by ginsenoside Rh1 (20mg/kg). In addition, ginsenoside Rh1 (20mg/kg) significantly increased mRNA expression of IFNγ and Foxp3, and slightly decreased IL-4 expression in draining lymph nodes. The results suggest that ginsenoside Rh1 can alleviate inflammatory symptoms in atopic dermatitis (AD) by reduction of IgE and IL-6 levels in peripheral blood, increase of Foxp3 expression in draining lymph nodes and suppression of inflammation in skin regions. Indeed, ginsenoside Rh1 exhibited therapeutic possibility in immune disorders.

Topics: Administration, Oral; Animals; Dermatitis, Atopic; Disease Models, Animal; Forkhead Transcription Factors; Ginsenosides; Immunoglobulin E; Immunologic Factors; Interferon-gamma; Interleukin-6; Lymph Nodes; Mice; Mice, Hairless; Molecular Structure; Oxazolone; Skin

Transient receptor potential vanilloid type 1 (TRPV1) is a cation channel activated by diverse obnoxious stimuli like capsaicin, low pH or heat. Recently, it was revealed that TRPV1 might be deeply associated with skin permeability barrier function, suggesting that modulation of TRPV1 might be beneficial for the skin disorders with barrier damages.. We aimed to investigate whether the blockade of TRPV1 activation might accelerate skin barrier recovery and alleviate atopic dermatitis (AD)-like symptoms, employing a novel TRPV1 antagonist, PAC-14028.. TRPV1 antagonistic effects of PAC-14028 in human keratinocytes and skin were confirmed through capsaicin-evoked calcium influx assay and capsaicin-induced blood perfusion increase. Effects of PAC-14028 on skin barrier recovery were examined in vivo tape-stripping-induced barrier disruption in hairless mice. To determine the effects of PAC-14028 on AD, Dermatophagoides farina (Df)- and oxazolone (OXZ)-induced AD models were employed.. PAC-14028 could inhibit capsaicin-evoked calcium influx in keratinocytes at sub-micromolar concentrations. This potent TRPV1 antagonistic activity in keratinocytes was manifested in vivo as the blockade of capsaicin-induced blood perfusion increase, and the accelerated barrier recovery from tape-stripping-induced barrier damages in hairless mice. PAC-14028 could also attenuate dermatitis-associated barrier damages in Df and OXZ models as determined by lower TEWL (trans-epidermal water loss), reformation of neutral lipid layer and reversion of changes in loricrin and filaggrin expression. Importantly, along with accelerated recovery of skin barrier function, PAC-14028 alleviated the general AD-like symptoms, including serum IgE increase, mast cell degranulation, scratching behavior and clinical severity of dermatitis.. These results reflect that the blockade of TRPV1 activation can suppress the atopic dermatitis-like symptoms by accelerating skin barrier recovery.

Topics: Acrylamides; Animals; Calcium; Capsaicin; Dermatitis; Dermatitis, Atopic; Female; Filaggrin Proteins; Humans; Immunoglobulin E; Intermediate Filament Proteins; Lipids; Mast Cells; Membrane Proteins; Mice; Oxazolone; Perfusion; Permeability; Pyridines; Skin; TRPV Cation Channels

Although topical glucocorticoids (GCs) show potent anti-inflammatory activity in inflamed skin, they can also exert numerous harmful effects on epidermal structure and function. In contrast, topical applications of ligands of peroxisome proliferator-activated receptor-α (PPARα) not only reduce inflammation but also improve cutaneous barrier homeostasis. Therefore, we examined whether sequential topical GCs followed by topical Wy14643 (a ligand of PPARα) might be more effective than either alone for atopic dermatitis (AD) in a hapten (oxazolone (Ox))-induced murine model with multiple features of AD (Ox-AD). Despite expected anti-inflammatory benefits, topical GC alone induced (i) epidermal thinning; (ii) reduced expression of involucrin, loricrin, and filaggrin; and (iii) allowed outside-to-inside penetration of an epicutaneous tracer. Although Wy14643 alone yielded significant therapeutic benefits in mice with mild or moderate Ox-AD, it was less effective in severe Ox-AD. Yet, topical application of Wy14643 after GC was not only significantly effective comparable with GC alone, but it also prevented GC-induced structural and functional abnormalities in permeability barrier homeostasis. Moreover, rebound flares were largely absent after sequential treatment with GC and Wy14643. Together, these results show that GC and PPARα ligand therapy together is not only effective but also prevents development of GC-induced side effects, including rebound flares, in murine AD.

Topics: Adjuvants, Immunologic; Animals; Clobetasol; Dermatitis, Atopic; Disease Models, Animal; Drug Synergism; Drug Therapy, Combination; Epidermis; Female; Glucocorticoids; Haptens; Mice; Mice, Hairless; Naphthols; Oxazolone; Peroxisome Proliferators; PPAR alpha; Pyrimidines; Secondary Prevention; Triazines

Skin protects the body from the environment and is an important component of the innate and adaptive immune systems. Atopic dermatitis and contact dermatitis are among the most frequent inflammatory skin diseases and are both determined by multigenic predisposition, environmental factors, and aberrant immune response. Peptidoglycan Recognition Proteins (Pglyrps) are expressed in the skin and we report here that they modulate sensitivity to experimentally-induced atopic dermatitis and contact dermatitis. Pglyrp3(-/-) and Pglyrp4(-/-) mice (but not Pglyrp2(-/-) mice) develop more severe oxazolone-induced atopic dermatitis than wild type (WT) mice. The common mechanism underlying this increased sensitivity of Pglyrp3(-/-) and Pglyrp4(-/-) mice to atopic dermatitis is reduced recruitment of Treg cells to the skin and enhanced production and activation Th17 cells in Pglyrp3(-/-) and Pglyrp4(-/-) mice, which results in more severe inflammation and keratinocyte proliferation. This mechanism is supported by decreased inflammation in Pglyrp3(-/-) mice following in vivo induction of Treg cells by vitamin D or after neutralization of IL-17. By contrast, Pglyrp1(-/-) mice develop less severe oxazolone-induced atopic dermatitis and also oxazolone-induced contact dermatitis than WT mice. Thus, Pglyrp3 and Pglyrp4 limit over-activation of Th17 cells by promoting accumulation of Treg cells at the site of chronic inflammation, which protects the skin from exaggerated inflammatory response to cell activators and allergens, whereas Pglyrp1 has an opposite pro-inflammatory effect in the skin.

Topics: Allergens; Animals; Blotting, Western; Carrier Proteins; Dermatitis, Atopic; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Immune System; Inflammation; Interleukin-17; Male; Mice; Mice, Inbred BALB C; Mice, Knockout; Oxazolone; Real-Time Polymerase Chain Reaction; RNA, Messenger; T-Lymphocytes, Regulatory

The incidence of chronic allergic dermatitis is rapidly increasing. Regulatory control of this disease has not been adequately explored. Here we report that mast cell-derived interleukin-2 (IL-2) contributes to the suppression of chronic allergic dermatitis. Mice deficient in IL-2 production, or deficient in mast cells (Kit(W-sh/W-sh)), showed exacerbated dermatitis upon repeated oxazolone challenge when compared to their wild-type counterparts. Adoptive transfer of wild-type, but not Il2(-/-), mast cells into Kit(W-sh/W-sh) mice dampened the inflammatory response. During the course of disease, mast cell expansion occurred at the site of inflammation and also in the spleen, where production of IL-2 by mast cells was markedly enhanced. In the absence of mast cell IL-2 production, the ratio of activated to regulatory T cells at the site of inflammation was increased. Thus, MC-derived IL-2 contributes to the maintenance of suppression in chronic allergic skin inflammation.

Topics: Animals; Chronic Disease; Dermatitis, Atopic; Immunoglobulin E; Interleukin-2; Mast Cells; Mice; Mice, Knockout; Oxazolone; Spleen

Atopic dermatitis (AD) is a chronic inflammatory dermatosis now increasingly linked to mutations that alter the structure and function of the stratum corneum. Activators of peroxisome proliferator-activated receptors (PPARs) alpha, beta/delta, and gamma and liver X receptor (LXR) regulate epidermal protein and lipid production, leading to superior barrier function. Additionally, some of these activators exhibit potent antihyperplastic and anti-inflammatory activity in irritant contact dermatitis and acute allergic contact dermatitis murine models.. We evaluated the efficacy of PPAR/LXR activation in a hapten (oxazolone [Ox])-induced AD-like model (Ox-AD) in hairless mice.. Ox-AD was established with 10 Ox challenges (every other day) on the flank. After the establishment of Ox-AD, twice-daily topical application with individual PPAR/LXR activators was then performed for 4 days, with continued Ox challenges every other day. The efficacy of topical PPAR/LXR activators to reduce parameters of Ox-AD was assessed physiologically, morphologically, and immunologically.. Certain topical activators of PPARalpha, PPARbeta/delta, and LXR, but not activators of PPARgamma, reversed the clinical dermatosis, significantly improved barrier function, and increased stratum corneum hydration in Ox-AD mice. In addition, the same activators, but again not PPARgamma, largely reversed the immunologic abnormalities in Ox-AD mice, including the increased T(H)2 markers, such as tissue eosinophil/mast cell density, serum thymus and activation-related chemokine levels, the density of chemoattractant receptor-homologous molecule expressed on T(H)2-positive lymphocytes (but not serum IgE levels), and reduced IL-1alpha and TNF-alpha activation, despite ongoing hapten challenges.. These results suggest that topical applications of certain activators/ligands of PPARalpha, PPARbeta/delta, and LXR could be useful for the treatment of AD in human subjects.

Topics: Administration, Topical; Animals; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Epidermis; Female; Humans; Liver X Receptors; Mice; Mice, Hairless; Orphan Nuclear Receptors; Oxazolone; Peroxisome Proliferator-Activated Receptors; PPAR alpha; PPAR delta; PPAR-beta; Th2 Cells; Treatment Outcome

Cathepsin S (CATS) is a cysteine protease, well known for its role in MHC class II-mediated antigen presentation and extracellular matrix degradation. Disturbance of the expression or metabolism of this protease is a concomitant feature of several diseases. Given this importance we studied the localization and regulation of CATS expression in normal and pathological human/mouse skin. In normal human skin CATS-immunostaining is mainly present in the dermis and is localized in macrophages, Langerhans, T- and endothelial cells, but absent in keratinocytes. In all analyzed pathological skin biopsies, i.e. atopic dermatitis, actinic keratosis and psoriasis, CATS staining is strongly increased in the dermis. But only in psoriasis, CATS-immunostaining is also detectable in keratinocytes. We show that cocultivation with T-cells as well as treatment with cytokines can trigger expression and secretion of CATS, which is involved in MHC II processing in keratinocytes. Our data provide first evidence that CATS expression (i) is selectively induced in psoriatic keratinocytes, (ii) is triggered by T-cells and (iii) might be involved in keratinocytic MHC class II expression, the processing of the MHC class II-associated invariant chain and remodeling of the extracellular matrix. This paper expands our knowledge on the important role of keratinocytes in dermatological disease.

Topics: Animals; Biopsy; Cathepsins; Cell Communication; Cell Line; Coculture Techniques; Cytokines; Dermatitis, Atopic; Disease Models, Animal; Humans; Keratinocytes; Major Histocompatibility Complex; Mice; Oxazolone; Psoriasis; T-Lymphocytes; Up-Regulation

Topics: Animals; Dermatitis, Atopic; Dermatophagoides farinae; Disease Models, Animal; Female; Immunoglobulin E; Immunohistochemistry; Male; Mast Cells; Mice; Mice, Hairless; Oxazolone; Picryl Chloride

We investigated pharmacological characteristics of the itch-associated response to chronic dermatitis induced by 4-ethoxymethylene-2-phenyl-2-oxazolin-5-one (oxazolone) repeated application in mice. Application of an oxazolone challenge to mice with oxazolone-induced chronic dermatitis evoked severe and transient scratching behavior for up to 1h. Thereafter, mild and continuous scratching behavior was observed for at least 8 h. Both severe and continuous scratching behaviors were suppressed by the opioid-receptor antagonist naltrexone, but not by the H(1) histamine-receptor antagonist fexofenadine, 5-hydroxytryptamine-2 (5-HT(2))-receptor antagonist methysergide, NK(1)-receptor antagonist LY303870, cyclooxygenase inhibitor indomethacin, or the platelet-activating factor-receptor antagonist YM264. The severe scratching behavior was suppressed by the 5-lipoxygenase inhibitor zileuton and leukotriene B(4)-receptor antagonist ONO-4057, but not by the cysteinyl leukotriene-receptor antagonist montelukast. The continuous scratching behavior was suppressed by pretreatment with the non-selective muscarinic acetylcholine-receptor antagonist atropine and M(3) muscarinic acetylcholine-receptor antagonist darifenacin. These results suggest that leukotriene B(4) receptor and M(3) muscarinic acetylcholine receptor are involved in the itch-associated response induced by repeated application of oxazolone in mice.

Topics: Animals; Anti-Allergic Agents; Antipruritics; Behavior, Animal; Dermatitis, Atopic; Dose-Response Relationship, Drug; Haptens; Leukotriene Antagonists; Male; Mice; Mice, Inbred BALB C; Muscarinic Antagonists; Oxazolone; Pruritus; Receptor, Muscarinic M3; Receptors, Leukotriene B4; Time Factors

Increase in the number of patients with atopic dermatitis (AD) has been recently reported. T helper (Th) cells that infiltrate AD skin lesions are Th2-type dominant; reduced exposure to environmental Th1-cytokine-inducing microbes is believed to contribute to the increased number of AD patients. Regulatory type immune responses have been also associated with the occurrence of AD. It has been reported that antigen 85B (Ag85B) purified from mycobacteria is a potent inducer of Th1-type immune response in mice as well as in humans. In this study, we have examined the effect of plasmid DNA encoding Ag85B derived from Mycobacterium kansasii on AD skin lesions induced by oxazolone (OX) application. Th2-cytokine mediated mouse AD model with immediate type response followed by a late phase reaction was developed by repeated applications of low-dose OX to sensitized mice. Mice were immunized with plasmid DNA encoding cDNA of Ag85B before OX sensitization or during repeated elicitation phase. Both therapies were associated with significant suppression of immediate type response, clinical appearance, dermal cell infiltration, reduced IL-4 production, and augmented IFN-gamma mRNA expression compared to placebo-treated mice. Additionally, increased number of Foxp3(+) regulatory T cells were observed in the skin sections in Ag85B treated mice. The results of this study suggest that Ag85B DNA vaccine is a potential therapy for Th2 type dermatitis.

Topics: Acute-Phase Reaction; Animals; Antigens, Bacterial; Cytokines; Dermatitis, Atopic; Disease Models, Animal; DNA; Forkhead Transcription Factors; Interferon-gamma; Interleukin-4; Male; Mice; Mice, Inbred BALB C; Oxazolone; Plasmids; T-Lymphocytes, Regulatory; Th2 Cells; Vaccines, DNA

Neutralization of stratum corneum (SC) adversely impacts key epidermal functions, including permeability barrier homeostasis and SC integrity. Conversely, acidification of SC improves these functions in developmentally impaired (neonatal or aged) skin, and enhances function in normal skin. Hence, we hypothesized that acidification could alter the course of inflammatory dermatoses, which invariably exhibit an increased SC pH. Maintenance of a low pH by topical applications of the polyhydroxyl acid, lactobionic acid, during the repeated-challenge phase inhibited the development of oxazolone-induced atopic dermatitis (AD). Neither gross/histological dermatitis nor altered barrier function developed, and emergence of epidermal hyperplasia was prevented; however, cytokine generation decreased. Acidification also largely normalized the development of hapten-induced changes in eosinophil/mast cell densities, density of chemoattractant receptor-homologous molecule expressed on TH2-positive lymphocytes, and serum IgE levels. The pH-induced improvement in barrier function most likely accounts for the anti-inflammatory activity, which could be further attributed to normalization of both lamellar body secretion and lamellar bilayer formation. Acidification of SC alone substantially prevents development of barrier abnormalities and downstream immune abnormalities during the elicitation phase of murine AD. These results provide direct evidence for the "outside-inside" pathogenesis of AD and further suggest that maintenance of an acidic SC pH could prevent the emergence of AD in humans.

Topics: Acute Disease; Adjuvants, Immunologic; Administration, Topical; Animals; Antimicrobial Cationic Peptides; Dermatitis, Allergic Contact; Dermatitis, Atopic; Disaccharides; Epidermis; Female; Haptens; Hydrogen-Ion Concentration; Immunoglobulin E; Lipid Bilayers; Mice; Mice, Hairless; Oxazolone; Serine Endopeptidases; Th2 Cells

Atopic dermatitis and allergic contact dermatitis are skin disorders triggered by epicutaneous sensitization with protein antigens and contact sensitization with haptens, respectively. Skin is colonized with bacteria, which are a source of Toll-like receptor (TLR) 2 ligands.. We sought to examine the role of TLR2 in murine models of atopic dermatitis and allergic contact dermatitis.. TLR2(-/-) mice and wild-type littermates were epicutaneously sensitized with ovalbumin (OVA) or contact sensitized with oxazolone (OX). Skin histology was assessed by means of hematoxylin and eosin staining and immunohistochemistry. Ear swelling was measured with a micrometer. Cytokine mRNA expression was examined by means of quantitative RT-PCR. Antibody levels and splenocyte secretion of cytokines in response to OVA stimulation were measured by means of ELISA. Dendritic cells were examined for their ability to polarize T-cell receptor/OVA transgenic naive T cells to T(H)1 and T(H)2.. In response to OVA sensitization, TLR2(-/-) mice experienced skin infiltration with eosinophils and CD4(+) cells, as well as upregulation of T(H)2 cytokine mRNAs that was comparable with that seen in wild-type littermates. In contrast, epidermal thickening, IFN-gamma expression in the skin, IFN-gamma production by splenocytes, and IgG2a anti-OVA antibody levels were impaired in TLR2(-/-) mice. After OX ear challenge, contact sensitized TLR2(-/-) mice exhibited defective ear swelling with impaired cellular infiltration, decreased epidermal thickening and local IFN-gamma expression, and impaired OX-specific IgG2a responses. Dendritic cells from TLR2(-/-) mice induced significantly lower production of IFN-gamma but normal IL-4 and IL-13 production in naive T cells.. These results indicate that TLR2 promotes the IFN-gamma response to cutaneously introduced antigens.

Topics: Animals; Dermatitis, Atopic; Female; Gene Expression Regulation; Immunoglobulin G; Interferon-gamma; Mice; Mice, Inbred C57BL; Ovalbumin; Oxazolone; Skin; Th1 Cells; Toll-Like Receptor 2

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents, Non-Steroidal; Chronic Disease; Cyclooxygenase 2; Dermatitis, Atopic; Female; I-kappa B Proteins; Lithospermum; Mice; NF-kappa B; NF-KappaB Inhibitor alpha; Nitric Oxide Synthase Type II; Oxazolone; Phytotherapy; Plant Extracts; Prednisolone; Skin

Mutations in the human filaggrin gene (FLG) are associated with atopic dermatitis (AD) and are presumed to provoke a barrier abnormality. Yet additional acquired stressors might be necessary because the same mutations can result in a noninflammatory disorder, ichthyosis vulgaris.. We examined here whether FLG deficiency alone suffices to produce a barrier abnormality, the basis for the putative abnormality, and its proinflammatory consequences.. By using the flaky-tail mouse, which lacks processed murine filaggrin because of a frameshift mutation in the gene encoding profilaggrin that mimics some mutations in human AD, we assessed whether FLG deficiency provokes a barrier abnormality, further localized the defect, identified its subcellular basis, and assessed thresholds to irritant- and hapten-induced dermatitis.. Flaky-tail mice exhibit low-grade inflammation with increased bidirectional, paracellular permeability of water-soluble xenobiotes caused by impaired lamellar body secretion and altered stratum corneum extracellular membranes. This barrier abnormality correlates with reduced inflammatory thresholds to both topical irritants and haptens. Moreover, when exposed repeatedly to topical haptens at doses that produce no inflammation in wild-type mice, flaky-tail mice experience a severe AD-like dermatosis with a further deterioration in barrier function and features of a T(H)2 immunophenotype (increased CRTH levels plus inflammation, increased serum IgE levels, and reduced antimicrobial peptide [mBD3] expression).. FLG deficiency alone provokes a paracellular barrier abnormality in mice that reduces inflammatory thresholds to topical irritants/haptens, likely accounting for enhanced antigen penetration in FLG-associated AD.

Topics: Adjuvants, Immunologic; Animals; Carcinogens; Dermatitis, Atopic; Filaggrin Proteins; Haptens; Immunoglobulin E; Intermediate Filament Proteins; Irritants; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; Microscopy, Electron, Transmission; Oxazolone; Skin; Tetradecanoylphorbol Acetate

Atopic dermatitis (AD) is a chronic dermatosis bearing clinical, histological, and immunologic similarities to chronic allergic contact dermatitis (ACD). AD shows a Th2 cell-dominant inflammatory infiltrate, elevated serum IgE levels, a permeability barrier abnormality, and Staphylococcus aureus colonization. Repeated hapten challenges reportedly produce a Th2-like hypersensitivity reaction (Th2-like HR). Here, 9-10 challenges with oxazolone (Ox) to hairless mice also produced a chronic Th2-like HR. Permeability barrier function and expression of differentiation proteins, filaggrin, loricrin, and involucrin, became abnormal. CRTH-positive Th2-dominant inflammatory infiltrate, with increased IL-4 expression, and a large increase in serum IgE levels were observed. The barrier abnormality was associated with decreased stratum corneum (SC) ceramide content and impaired lamellar body secretion, resulting in abnormal lamellar membranes, as in human AD. Furthermore, as in human AD, epidermal serine protease activity in SC increased and expression of two lamellar body-derived antimicrobial peptides, CRAMP and mBD3, declined after Ox challenges, paralleling the decrease of their human homologues in AD. Thus, multiple Ox challenges to normal murine skin produce a chronic Th2-like HR, with multiple features of human AD. Because of its reproducibility, predictability, and low cost, this model could prove useful for evaluating both pathogenic mechanisms and potential therapies for AD.

Topics: Animals; Antimicrobial Cationic Peptides; Cathelicidins; Ceramides; Dermatitis, Atopic; Disease Models, Animal; DNA-Binding Proteins; Female; Filaggrin Proteins; Haptens; Immunity, Innate; Immunoglobulin E; Lipids; Mice; Mice, Hairless; Oxazolone; Permeability; Serine Endopeptidases; Th2 Cells; Transcription Factors

Chronic contact hypersensitivity (CH) models induced by repeated hapten exposure exhibit chronic dermatitis and immunological abnormalities resembling atopic dermatitis. To assess the contribution of endothelial selectins (P- and E-selectins) to cutaneous chronic inflammation, chronic CH responses were assessed in mice lacking P- or E-selectin. Elicitation with oxazolone on the ears of P-selectin(-/-) mice 7 days after the sensitization induced a typical delayed-type hypersensitivity response similar to that found in wild-type mice. By contrast, a significant increase in ear swelling was observed in E-selectin(-/-) mice 36 to 48 hours after first elicitation. E-selectin(-/-) mice showed augmented P-selectin up-regulation, and administration of anti-P-selectin monoclonal antibody significantly inhibited the enhanced ear response, suggesting that the enhanced ear-swelling response in E-selectin(-/-) mice resulted from compensatory increase in P-selectin expression. In the late phase of chronic CH, acceleration of ear swelling was significantly reduced in both E- and P-selectin(-/-) mice relative to wild-type littermates. Thus, the loss of P- or E-selectin suppressed inflammatory responses during the chronic phase of the chronic models, whereas early-phase inflammatory responses were exacerbated by E-selectin blockade. Collectively, P- and E-selectins cooperatively regulate CH response, although their roles may be different depending on the phase of the reaction.

Topics: Adjuvants, Immunologic; Animals; Chronic Disease; Dermatitis, Atopic; Dermatitis, Contact; E-Selectin; Immunohistochemistry; Inflammation; Mice; Mice, Inbred C57BL; Oxazolone; P-Selectin; Reverse Transcriptase Polymerase Chain Reaction

To understand further the possible clinical effects of tinidazole ointment at relatively high concentration (2%) for atopic dermatitis (AD), we performed a comparative study with readily available topical corticosteroids, clobetasol propionate (0.005 or 0.05%) and hydrocorotisone butyrate (0.1%) (hereafter referred as clobetasol and hydrocortisone, respectively), on inflammatory dermatitis in mice. We also observed the effects of combined application of tinidazole with clobetasol (0.005%, one tenth of the clinical use) in comparison with tinidazole itself, clobetasol (0.05%) or hydrocortisone (0.1%) on the animal model. All ointments suppressed inflammatory dermatitis induced by trinitrochlorobenzen (TNCB) or oxazolone. The rank order of the potency to suppress the ear edema was clobetasol (0.05%), tinidazole (2%) with clobetasol (0.005%) > clobetasol (0.005%) > tinidazole (2%) in TNCB-induced dermatitis, and hydrocortisone (0.1%), clobetasol (0.05%) > tinidazole (2%), tinidazole with clobetasol (0.005%) > clobetasol (0.005%) in case of oxazolone-induced dermatitis. We confirmed that tinidazole (2%) suppresses immediate and late phase reactions in mice passively sensitized with anti-DNP IgE Mab. In addition, tinidazole (2%) was much more potent than hydrocortisone (0.1%) in suppressing the amount of scratching, presumably due to itching, in passively sensitized mice. These results indicate that the advantage of using ointments of tinidazole would be that it has stronger anti-itching effects than corticosteroids.

Topics: Adjuvants, Immunologic; Administration, Topical; Animals; Antibodies, Monoclonal; Clobetasol; Dermatitis, Atopic; Dinitrophenols; Disease Models, Animal; Drug Therapy, Combination; Hydrocortisone; Immunoglobulin E; Male; Mice; Mice, Inbred Strains; Ointments; Ovalbumin; Oxazolone; Picryl Chloride; Tinidazole