HR-1 Mice Research Articles

The beneficial effects of ethanolic extract of Sargassum serratifolium in DNCB-induced mouse model of atopic dermatitis

Atopic dermatitis is a chronic complex inflammatory skin disorder that requires sustainable treatment methods due to the limited efficacy of conventional therapies. Sargassum serratifolium, an algal species with diverse bioactive substances, is investigated in this study for its potential benefits as a therapeutic agent for atopic dermatitis. RNA sequencing of LPS-stimulated macrophages treated with ethanolic extract of Sargassum serratifolium (ESS) revealed its ability to inhibit a broad range of inflammation-related signaling, which was proven in RAW 264.7 and HaCaT cells. In DNCB-induced BALB/c or HR-1 mice, ESS treatment improved symptoms of atopic dermatitis within the skin, along with histological improvements such as reduced epidermal thickness and infiltration of mast cells. ESS showed a tendency to improve serum IgE levels and inflammation-related cytokine changes, while also improving the mRNA expression levels of Chi3l3, Ccr1, and Fcεr1a genes in the skin. Additionally, ESS compounds (sargachromanol (SCM), sargaquinoic acid (SQA), and sargahydroquinoic acid (SHQA)) mitigated inflammatory responses in LPS-treated RAW264.7 macrophages. In summary, ESS has an anti-inflammatory effect and improves atopic dermatitis, ESS may be applied as a therapeutics for atopic dermatitis.

Particulate matter-induced skin inflammation is suppressed by polyphenol-enriched dietary supplement via inhibition of the AhR/ARNT signaling pathway

Environmental factors that cause skin diseases cause an inflammatory response and cause various diseases. In this study, the ability of polyphenol-enriched dietary supplement (Zeropollution, ZP), a mixture of four types of natural extracts, to inhibit skin inflammation caused by particulate matter (PM) and ultraviolet B (UVB), was evaluated using an experimental mouse model (HR-1 or SKH-1 mice) and human keratinocytes (HaCaT cells). Treatment with ZP significantly inhibited the levels of pro-inflammatory markers, such as cyclooxygenase-2 (COX-2) and cytochrome P450 family 1 subfamily A1 (CYP1A1). In addition, the pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α) and interleukin-1α (IL-1α), were decreased by ZP pretreatment before exposure to PM10 or UVB. In particular, ZP significantly inhibited the expression of the aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (ARNT), which initiate inflammatory responses by sensing PM10 and UVB. Therefore, these results suggest that ZP has the potential to be used as a material for the development of a naturally derived functional compound that can prevent skin aging triggered by PM10 and UVB.

Protective effect of Schizonepeta tenuifolia Briq. ethanolic extract against UVB-induced skin aging and photodamage in hairless mice.

The purpose of this study was to illuminate the mechanism by which Schizonepeta tenuifolia Briq. (ST) ethanolic extract prevents skin photoaging in HR-1 hairless mice (HR-1). The ST ethanolic extract alleviated wrinkle formation, epidermal skin thickness, and collagen degradation in skin tissues of ultraviolet B (UVB)-irradiated HR-1 mice. Expression of matrix metalloproteinases (a wrinkle-related marker) was reduced, and tissue inhibitor of metalloproteinase 1 expression was upregulated following application of ST ethanolic extract. Furthermore, skin dehydration and levels of hyaluronidase-1 and -2 (enzymes that break hyaluronic acid) were decreased. Moreover, protein expression of hyaluronan synthases (markers of skin hydration) and hyaluronic acid levels increased following ST ethanolic extract treatment in UVB-induced photoaging HR-1 mice. In addition, the phosphorylation of mitogen-activated protein kinases (MAPKs), including p38, extracellular signal-regulated kinase, and Jun N-terminal kinase was suppressed, and expression of nuclear factor-kappa was reduced. Treatment with ST ethanolic extract also reduced advanced glycation end product (AGE) accumulation and expression of the receptor for AGE (RAGE) in skin tissue. These results suggest that ST ethanolic extract moderates skin damage caused by UVB irradiation via regulating the expression of wrinkle- and hydration-related proteins, MAPKs, and RAGE.

Lactic acid bacteria and their lysate ameliorate skin inflammation in a UVB irradiation-induced skin photoaging mouse model

Skin photoaging is premature skin aging caused by over exposure to ultraviolet (UV) radiation. Photoaged skin is characterized by epidermal thickening, dryness, deep wrinkles, loss of elasticity, delayed wound healing and susceptibility to cancer and closely related to skin inflammation. Meanwhile, it had been reported that lactic acid bacteria (LAB) lysate has lots of beneficial components such as fatty acid, vitamin B, and amino acids, and LAB has the anti-inflammatory effects and the potentials as therapeutics for many chronic inflammatory diseases. Because skin photoaging is recovered by reducing inflammation, co-treatment of LAB and their lysate may alleviate the skin conditions caused by UV-induced skin photoaging via the anti-inflammatory effects. Therefore, the aim of this study is to find out whether co-treatment of LAB and their lysate has beneficial effects on skin conditions and ameliorates skin photoaging. LAB and their lysate were treated in vitro and in vivo. LAB lysate decreased the expression levels of pro-inflammatory cytokines including TNF-α and other inflammation-related biomarkers such as cyclooxygenase 2 (COX-2) and toll-like receptor 4 (TLR4) significantly in HaCaT, the human keratinocyte cell line. LAB and their lysate was evaluated in UVB-induced skin photoaged HR-1 mice model, and it decreased the pro-inflammatory cytokines including TNF-α in serum. LAB and their lysate also decreased pro-inflammatory cytokines in skin, colon, and spleen. Moreover, LAB and their lysate changed the composition of fecal microbiome and short chain fatty acids in mice. In conclusion, the topical treatment of lactic acid bacteria and their lysate may have a potential to ameliorate skin photoaging by reducing inflammation. This work was supported by Korea Testing Laboratory This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Latilactobacillus sakei Wikim0066 Protects Skin through MMP Regulation on UVB-Irradiated In Vitro and In Vivo Model.

Ultraviolet (UV) B exposure induces wrinkle formation, collagen fiber breakdown, and transepidermal water loss (TEWL). UVB irradiation induces the expression of mitogen-activated protein kinase (MAPK), activator protein 1 (AP-1), and nuclear factor kappa B (NF-κB), which affect the expression of matrix metalloproteinases (MMP). We confirmed the effects of Latilactobacillus sakei wikim0066 (wikim0066) on UVB-irradiated Hs68 cells and HR-1 hairless mice cells. wikim0066 restored the production of type I procollagen by regulating the expression of MMP-1 and -3, MAPK, AP-1, and NF-κB in UVB-irradiated Hs68 cells and HR-1 mice. Oral administration of wikim0066 alleviates wrinkle formation, epidermal thickness, and TEWL in UVB-irradiated HR-1 hairless mice. These results indicated that wikim0066 has the potential to prevent UVB-induced wrinkle formation.

Light-Touch-Induced Afterdischarge Firing in the Superficial Spinal Dorsal Horn Neurons in Hairless Mice with Irritant Contact Dermatitis.

The skin is an important barrier that protects against invasion by foreign substances, including irritants and harmful microorganisms, and holds water in the body. Washing the skin with cleansers and shampoos containing anionic surfactants, for example sodium dodecyl sulfate (SDS), is important for maintaining skin homeostasis. However, surfactants can cause dermatitis, cutaneous hypersensitivity (e.g., alloknesis), and pruritus in humans. Our previous studies revealed an alloknesis response in the skin with SDS-induced dermatitis in C57BL/6 mice. In addition, we found that alloknesis responses and afterdischarge responses following stimulation with light touch are related because they are observed contemporaneously. In this study, we used Hos:HR-1 hairless mice to establish a mouse model to evaluate long-term drug application for alloknesis responses. Alloknesis was observed in HR-1 mice with SDS-induced dermatitis. The mean number of c-Fos (a marker of neural activity) immunopositive neurons was increased in the lamina 1-2 (L1-2) spinal dorsal horn, but not in L3-4, of SDS-treated HR-1 mice compared to vehicle-treated mice. We also discovered that afterdischarge responses were observed in neurons in L1-2. There was also a correlation between the intensity of the afterdischarge responses and depth of the recording site. Thus, the following were suggested: 1) neurons that mediate these afterdischarge responses are located on the superficial layer of the spinal cord; 2) afterdischarge responses can be an index of alloknesis responses, and 3) the mouse model of SDS-induced dermatitis is an appropriate alloknesis model.

UV-induced DNA Damage in Skin is Reduced by CaSR Inhibition.

ABSTRACTThe epidermis maintains a cellular calcium gradient that supports keratinocyte differentiation from its basal layers (low) to outer layers (high) leading to the development of the stratum corneum, which resists penetration of UV radiation. The calcium‐sensing receptor (CaSR) expressed in keratinocytes responds to the calcium gradient with signals that promote differentiation. In this study, we investigated whether the CaSR is involved more directly in protection from UV damage in studies of human keratinocytes in primary culture and in mouse skin studied in vivo. siRNA‐directed reductions in CaSR protein levels in human keratinocytes significantly reduced UV‐induced direct cyclobutane pyrimidine dimers (CPD) by ~80% and oxidative DNA damage (8‐OHdG) by ~65% compared with control transfected cells. Similarly, in untransfected cells, the CaSR negative modulator, NPS‐2143 (500 nm), reduced UV‐induced CPD and 8‐OHdG by ~70%. NPS‐2143 also enhanced DNA repair and reduced reactive oxygen species (ROS) by ~35% in UV‐exposed keratinocytes, consistent with reduced DNA damage after UV exposure. Topical application of NPS‐2143 also protected hairless Skh:hr1 mice from UV‐induced CPD, oxidative DNA damage and inflammation, similar to the reductions observed in response to the well‐known photoprotection agent 1,25(OH)2D3 (calcitriol). Thus, negative modulators of the CaSR offer a new approach to reducing UV‐induced skin damage.

Sex Differences in Photoprotective Responses to 1,25-Dihydroxyvitamin D3 in Mice Are Modulated by the Estrogen Receptor-β.

Susceptibility to photoimmune suppression and photocarcinogenesis is greater in male than in female humans and mice and is exacerbated in female estrogen receptor-beta knockout (ER-β−/−) mice. We previously reported that the active vitamin D hormone, 1,25-dihydroxyvitamin D3 (1,25(OH)2D), applied topically protects against the ultraviolet radiation (UV) induction of cutaneous cyclobutane pyrimidine dimers (CPDs) and the suppression of contact hypersensitivity (CHS) in female mice. Here, we compare these responses in female versus male Skh:hr1 mice, in ER-β−/−/−− versus wild-type C57BL/6 mice, and in female ER-blockaded Skh:hr1 mice. The induction of CPDs was significantly greater in male than female Skh:hr1 mice and was more effectively reduced by 1,25(OH)2D in female Skh:hr1 and C57BL/6 mice than in male Skh:hr1 or ER-β−/− mice, respectively. This correlated with the reduced sunburn inflammation due to 1,25(OH)2D in female but not male Skh:hr1 mice. Furthermore, although 1,25(OH)2D alone dose-dependently suppressed basal CHS responses in male Skh:hr1 and ER-β−/− mice, UV-induced immunosuppression was universally observed. In female Skh:hr1 and C57BL/6 mice, the immunosuppression was decreased by 1,25(OH)2D dose-dependently, but not in male Skh:hr1, ER-β−/−, or ER-blockaded mice. These results reveal a sex bias in genetic, inflammatory, and immune photoprotection by 1,25(OH)2D favoring female mice that is dependent on the presence of ER-β.

Anti-allergic effect of the Src family kinase inhibitor saracatinib.

The aim of this study was to evaluate the anti-anaphylactic and anti-allergic potentials of saracatinib, a Src family kinase inhibitor that was already shown to be safe in clinical trials when it was used as an anti-cancer drug. Using in vitro mast cell models, we found that saracatinib inhibited the degranulation response and cytokine production in RBL2H3 cells that were stimulated with IgE and antigen without affecting cell viability. Phosphorylation of Lyn, Akt, a PI3K substrate, and MAPKs including ERK, JNK, and p38, as well as the intracellular Ca2+ increase induced by this stimulation were also suppressed by saracatinib. This drug also inhibited symptoms in our established anaphylaxis mouse model, anaphylaxis-dependent spotted distribution of immune complex in skin (ASDIS). The intravenous injection of the mixture of IgE and antigen induced acute spotted distribution of immune complex in skin in hairless HR-1 mice, and its inhibition by intradermal injection of saracatinib was observed. Moreover, toluidine blue-stained skin sections indicated that the degranulation ratio of dermal mast cells was reduced in saracatinib-treated skin compared with vehicle-treated skin. Because only a few signaling inhibitors are used as anti-anaphylaxis and anti-allergic drugs, these results indicated the valuable suggestion that saracatinib and the Src family kinase inhibitors are good candidates for anti-anaphylaxis and anti-allergic drugs.

Anti-Inflammatory Effects of Bee Venom on Phthalic Anhydride-Induced Atopic Dermatitis

Background: Atopic dermatitis (AD) is a chronic inflammatory condition which can be studied using phthalic anhydride (PA) to induce AD. Anti-inflammatory properties of bee venom (BV) wereinvestigated to determine whether it may be a useful treatment for AD.Methods: AD was induced by applying to pical PA to 8-week-old HR-1 mice (<i>N</i> = 50), then treating with (0.1, 0.25, and 0.5 ?g) or without topical BV. Body weight, ear thickness histology, enzymelinked immune sorbent assay (serum IgE concentrations), Western blot analysis [inducible nitric oxide synthase, cyclooxygenase-2, IκB-α, phospho-IκB-α, c-Jun N-terminal kinase (JNK), phosphoJNK, p38, phospho-p38, extra cellular signal-regulated kinase (ERK), and phospho-ERK], and the pull down assay for immunoblotting (p50), were used to measure inflammatory mediators.Results: PA + BV (0.1, 0.25, and 0.5 μg) significantly decreased ear thickness without altering body weight. IgE concentrations decreased in the PA + BV (0.5 ?g)-treated groups compared with PAtreatment. Tumor necrosis factor-α, interleukin-1β, inducible nitric oxide synthase, cyclooxygenase-2, phospho-IκB-α, phospho-JNK, p38, phospho-p38, and phospho-ERK, all decreased following treatment with PA + BV compared with the PA-treatment alone. p50 was upregulated in the PA + BV-treated groups compared with the PA-treated group. Furthermore, the number of mast cells decreased in the PA + BV-treated groups compared with the PA-treated group. Epidermal thickness was significantly lower in the PA + BV-treated group compared with PA treatment alone.Conclusion: BV maybe a useful anti-inflammatory treatment for AD.

Oral administration of pineapple glucosylceramide improves defective epidermal barrier function by restoring diminished level of TGF-β in the skin

It was reported that oral administration of glucosylceramide (GlcCer) from plants ameliorates skin barrier function. GlcCer is a type of glycosphingolipid that exists widely as a component of the cell membrane. However, the mechanism of improvement by dietary GlcCer is not completely understood. The aim of the present study was to investigate the mechanism of GlcCer in the improvement of skin barrier function. Five-week-old male Hos:HR-1 mice were divided into three groups fed on standard diet, unsaturated fatty acids-deficient (HR-AD) diet, and HR-AD diet supplemented with 0.1% P-GlcCer diet. Skin barrier function was evaluated by transepidermal water loss (TEWL) value and wrinkle formation. The effect of transforming growth factor-β (TGF-β) on skin barrier function and collagen content in skin was examined using exogenous TGF-β and its neutralizing antibody. TEWL value and wrinkle formation were decreased by oral administration of pineapple (P)-GlcCer. Not only the TGF-β contents in serum and skin but also hydroxyproline content reduced by the HR-AD diet were restored by P-GlcCer administration. Exogenous TGF-β ameliorated both skin barrier function and collagen contents. However, the improvement of skin barrier function by P-GlcCer was cancelled and collagen content in skin was also decreased by TGF-β antibody injection. Recovery of TGF-β content by P-GlcCer contributed to the production of collagen in skin, resulting in improved skin barrier function.

Anti-inflammatory effects of Capparis ecuadorica extract in phthalic-anhydride-induced atopic dermatitis of IL-4/Luc/CNS-1 transgenic mice

Context The natural products derived from Capparis ecuadorica H.H. Iltis (Capparaceae) could have great potential for anti-inflammation since they inhibited the inflammatory response in lipopolysaccharide (LPS)‐stimulated RAW 264.7 cells. Object This study investigated the anti-inflammatory effects and related mechanism of methanol extract of C. ecuadorica leaves (MCE) during atopic dermatitis (AD) responses. Materials and methods Alterations in the phenotypical markers for AD, luciferase signal, iNOS‐mediated COX‐2 induction pathway, and inflammasome activation were analysed in non-Tg (n = 5) and 15% phthalic anhydride (PA) treated IL-4/Luc/CNS-1 transgenic (Tg) HR1 mice (n = 5 per group), subsequent to treatment with acetone-olive oil (AOO), vehicle (DMSO) and two dose MCE (20 and 40 mg/kg) three times a week for 4 weeks. Results MCE treatment reduced the intracellular ROS level (48.2%), NO concentration (7.1 mmol/L) and inflammatory cytokine expressions (39.1%) in the LPS-stimulated RAW264.7 cells. A significant decrease was detected for ear thickness (16.9%), weight of lymph node (0.7 mg), IgE concentration (1.9 µg/mL), and epidermal thickness (31.8%) of the PA + MCE treated Tg mice. MCE treatment induced the decrease of luciferase signal derived from the IL-4 promoter and the recovery of the IL-4 downstream regulator cytokines. PA + MCE treated Tg mice showed decreasing infiltration of mast cells (42.5%), iNOS-mediated COX‐2 induction pathway, MAPK signalling pathway and inflammasome activation in the ear tissue. Conclusions These findings provide the first evidence that MCE may have great potential to suppress chemical-induced skin inflammation through the suppression of IL-4 cytokine and the iNOS-mediated COX‐2 induction pathway, and activation of inflammasome.

Long-term UVA exposure to the eye compromises memory and learning ability in mice via corticotropin-releasing hormone type 2 receptor.

Long-term eye exposure to ultraviolet (UV)A can effect memory and learning ability. However, the underlying mechanism behind these effects remain unknown. In this study, we used HR-1 mice to study effects of long-term UVA eye irradiation. The eyes or dorsal skin of the mice were exposed to UVA at the dose of 110kj/m2 using an FL20SBLB-A lamp three times a week over 12 months. We measured the levels of reactive oxygen species, corticotropin-releasing hormone (CRH), urocortin 2, and CRH type 2 receptor (CRHR-2) in the brain of treated and control animals. Their memory and learning ability following exposure to UVA was analyzed by the standard water maze test. Our results showed that the levels of reactive oxygen species, CRH, urocortin 2, and CRHR-2 increased significantly following long-term UVA irradiation, and the effects were more pronounced in animals subjected to eye irradiation than those subjected to dorsal skin irradiation. Furthermore, the UVA exposure led to an increase in the levels of β-amyloid and microglia in the brain. These results indicated that UVA eye irradiation potentially mediated a decline in memory and learning ability via enhancing levels of urocortin 2, microglia, and β-amyloid in the brain.

Acute-phase effects of single-time topical or systemic corticosteroid application immediately after hot water-induced burn injury of various grades

The aim of this study is to evaluate the effects of corticosteroid application on each grade of burn, and to clarify the underlying mechanisms of the effects, especially in its acute inflammatory phase. To generate three-graded burn models (epidermal burn, or EB; dermal burn, or DB; and subcutaneous burn, or SB), hot water was applied on the back skin of Hos:HR-1 mice. Strongest-class (or high-potent) corticosteroid ointment (DD group) or petrolatum (control group) was applied on the back immediately after the hot water application on mice. Prednisolone sodium succinate (PDN group), 1 mg/kg was orally applied immediately after the hot water application on mice. The mice were sacrificed 1–3 days after hot water application, and the lesional skin samples were provided for histological assessment to enumerate the number of infiltrating inflammatory cells. The mRNA expression levels of inflammatory cytokines (IL-1b, TNFa, IL-6 and IFNg) in the lesional skin were also investigated. As a result, corticosteroid application suppressed the number of infiltrating inflammatory cells in the DD group of EB and SB at the early phase, and in DB at all time-points. However, the number of infiltrating inflammatory cells increased in EB on day 3. Expression of cytokines was generally suppressed in the PDN group of SB. In the cases of EB and DB, some cytokines had decreased but many of the others showed increased expression. In conclusion, the anti-inflammatory effects of corticosteroids are not simple inhibitory effects on inflammatory cell infiltration and cytokine production, but exert more complicated effects in vivo.

Combination Effect of Titrated Extract of Centella asiatica and Astaxanthin in a Mouse Model of Phthalic Anhydride-Induced Atopic Dermatitis.

PurposeIn our previous study, we demonstrated that both titrated extract of Centella asiatica (TECA) and astaxanthin (AST) have anti-inflammatory effects in a 5% phthalic anhydride (PA) mouse model of atopic dermatitis (AD). The increasing prevalence of AD demands new therapeutic approaches for treating the disease. We investigated the therapeutic efficacy of the ointment form of TECA, AST and a TECA + AST combination in a mouse model of AD to see whether a combination of the reduced doses of 2 compounds could have a synergistic effect.MethodsAn AD-like lesion was induced by the topical application of 5% PA to the dorsal ear and back skin of an Hos:HR-1 mouse. After AD induction, TECA (0.5%), AST (0.5%) and the TECA (0.25%) + AST (0.25%) combination ointment (20 μg/cm2) were spread on the dorsum of the ear or back skin 3 times a week for 4 weeks. We evaluated dermatitis severity, histopathological changes and changes in protein expression by Western blotting for inducible nitric oxide synthase (iNOS), cyclocxygenase (COX)-2, and nuclear factor (NF)-κB activity. We also measured the concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and immunoglobulin E (IgE) in the blood of AD mice by enzyme-linked immunosorbent assay (ELISA).ResultsPA-induced skin morphological changes and ear thickness were significantly reduced by TECA, AST and TECA + AST treatments, but these inhibiting effects were more pronounced in the TECA + AST treatment. TECA, AST and the TECA+AST reatments inhibited the expression of iNOS and COX-2; NF-κB activity; and the release of TNF-α, IL-6 and IgE. However, the TECA+AST treatment showed additive or synergistic effects on AD.ConclusionsOur results demonstrate that the combination of TECA and AST could be a promising therapeutic agent for AD by inhibiting NF-κB signaling.

Efficacy of Bacteriophages in Propionibacterium acnes-Induced Inflammation in Mice.

BackgroundBacteriophages have been introduced as living drugs for infectious diseases; thus, they may provide an alternative to conventional acne therapeutics in patients with non-responsive acne.ObjectiveWe investigated the effect of bacteriophages using an acne mouse model with Propionibacterium acnes-induced inflammatory nodules by clinical examination, pathology, and immunohistochemical analysis.MethodsA human-isolated P. acnes suspension (109 colony forming units/µl) was injected into the backs of HR-1 mice. Group A was used as a control, Group B was injected on the back with P. acnes 4 weeks following the initial P. acnes suspension injection, and group C was injected on the back with P. acnes and bacteriophages 4 weeks following the initial P. acnes suspension injection. Clinical and histopathological evaluations were performed.ResultsInflammatory nodule size decreased with time in all groups. Group C showed the greatest decrease in size, followed by group B and group A. The histopathological findings showed a decrease in epidermal thickness and the number and size of microcomedone-like cysts in groups B and C compared to group A. Immunohistochemistry revealed similar expression of integrin α6, the epidermal proliferation marker, infiltration of CD4/CD8 T cells and neutrophils, and expression of myeloperoxidase, interleukin-1β, toll-like receptor-2, LL-37, and matrix metalloproteinase-2/3/9 in all three groups.ConclusionUsing an acne mouse model with P. acnes-induced inflammatory nodules, we demonstrate that bacteriophages may constitute an alternative to conventional acne therapies. However, additional studies are needed for human applications.

Influence of Oral Administration of Lactic Acid Bacteria Metabolites on Skin Barrier Function and Water Content in a Murine Model of Atopic Dermatitis.

The effects of orally administered lactic acid bacteria metabolites on skin were studied using an atopic dermatitis-like murine model generated by feeding HR-AD to mice. Lactic acid bacteria metabolites were obtained by inoculating and culturing soy milk with 35 strains of 16 species of lactic acid bacteria. The atopic dermatitis-like murine model was generated by feeding HR-AD to HR-1 mice for 40 days. The skin condition of HR-AD-fed mice worsened compared with normal mice, showing reduced water content in the stratum corneum, increased transepidermal water loss (TEWL), reduced ceramide AP content in the stratum corneum, and increased epidermis thickness. When HR-AD-fed mice were orally administered a raw liquid containing lactic acid bacteria metabolites, water content in the stratum corneum, TEWL, ceramide AP content in the stratum corneum, and epidermis thickness improved. To determine the active components responsible for these effects, filtrate, residue, and lipid components extracted from the raw liquid containing lactic acid bacteria metabolites were examined. While water-soluble components and residue obtained after filtration had no effects, the lipid fraction showed similar effects to the raw liquid. These findings suggest that lactic acid bacteria metabolites improve skin injury in an atopic dermatitis-like murine model.

Inhibitory effect of Carnosol on UVB-induced inflammation via inhibition of STAT3

Ultraviolet B (UVB) irradiation causes sunburn, inflammatory responses, dysregulation of immune function, oxidative stress, DNA damage and photocarcinogenesis on skin. Rosemary (Rosmarinus officinalis L.) has been reported to inhibit inflammation. Carnosol, a major component of Rosemary, has prominent anti-inflammatory effects. However, its protective effect on UVB-induced inflammatory skin responses has not yet been reported. Here, we investigated the effectiveness of carnosol on UVB-induced inflammation. We examined the anti-inflammation effect of topical application of carnosol (0.05 µg/cm2) on UVB (540 mJ/cm2, for 3 successive days)-induced skin inflammation in HR1 mice. Topical application of carnosol inhibited UVB-induced erythema, epidermal thickness, inflammatory responses in HR1 mice. Carnosol reduced the level of Immunoglobulin-E and IL-1β in blood serum of UVB-induced mice. Carnosol also significantly inhibited the UVB-induced expression of inflammatory marker protein (iNOS and COX-2) in back skin of mice. In addition, carnosol treated skin decreased activation of STAT3, a transcriptional factor regulating inflammatory genes. Our study suggested that carnosol has protective effects on skin inflammatory skin damages by UVB.

Anti-inflammatory effect of astaxanthin in phthalic anhydride-induced atopic dermatitis animal model.

In this study, we investigated anti-dermatitic effects of astaxanthin (AST) in phthalic anhydride (PA)-induced atopic dermatitis (AD) animal model as well as in vitro model. AD-like lesion was induced by the topical application of 5% PA to the dorsal skin or ear of Hos:HR-1 mouse. After AD induction, 100μL of 1mg/mL and 2mg/mL of AST (10μg or 20μg/cm2 ) was spread on the dorsum of ear or back skin three times a week for four weeks. We evaluated dermatitis severity, histopathological changes and changes in protein expression by Western blotting for inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and nuclear factor-κB (NF-κB) activity. We also measured tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and immunoglobulin E (IgE) concentration in the blood of AD mice by enzyme-linked immunosorbent assay (ELISA). AST treatment attenuated the development of PA-induced AD. Histological analysis showed that AST inhibited hyperkeratosis, mast cells and infiltration of inflammatory cells. AST treatment inhibited expression of iNOS and COX-2, and NF-κB activity as well as release of TNF-α, IL-1β, IL-6 and IgE. In addition, AST (5, 10 and 20μM) potently inhibited lipopolysaccharide (LPS) (1μg/mL)-induced nitric oxide (NO) production, expression of iNOS and COX-2 and NF-κB DNA binding activities in RAW 264.7 macrophage cells. Our data demonstrated that AST could be a promising agent for AD by inhibition of NF-κB signalling.

Anti-inflammatory effect of Centella asiatica phytosome in a mouse model of phthalic anhydride-induced atopic dermatitis

BackgroundCentella asiatica phytosome (CA phytosome) has potent antioxidant and anti-inflammatory properties. However, its anti-dermatitic effect has not yet been reported. PurposeWe investigated the effects of CA phytosome on inflammatory reponses by macrophages in an atopic dermatitis (AD) mouse model. Study designThe effects of CA phytosome on atopic dermatitis were examined by using phthalic anhydride (PA)-induced AD mouse model and RAW 264.7 murine macrophages. MethodsAn AD-like lesion was induced by a topical application of 5% phthalic anhydride (PA) to the dorsal skin or ear of HR-1 mice. After AD induction, 100 µl (20 µl/cm2) of 0.2% and 0.4% CA phytosome was spread on the dorsal skin and ear of the mice three times a week for four weeks. We evaluated histopathological changes and changes in protein expression by Western blotting for iNOS and COX-2; NF-κB activity was determined by EMSA. We also measured TNF-α, IL-1β, and IgE concentration in the blood of AD mice by ELISA. ResultsHistological analysis showed that CA phytosome inhibited infiltration of inflammatory cells. CA phytosome treatment inhibited the expression of iNOS and COX-2, activity of NF-κB, and release of TNF-α, IL-1β, and IgE. In addition, CA phytosome (5, 10, and 20 µg/ml) potently inhibited LPS (1 µg/ml)-induced NO production as well as iNOS and COX-2 expression in RAW 264.7 macrophage. Furthermore, CA phytosome inhibited LPS-induced DNA binding activities of NF-κB, and this was associated with the discontinuation of IκBα degradation and subsequent decreases in the translocation of p65 and p50 into the nucleus. ConclusionFrom our data, CA phytosome application, which operates via NF-κB signaling inhibition, seems to be a promising AD treatment. Herein, we investigated the effects of Centella asiatica phytosome (CA phytosome) on inflammatory responses by macrophages in an atopic dermatitis (AD) mouse model. An AD-like lesion was induced by the topical application of 5% phthalic anhydride (PA) to the dorsal skin or ear of HR-1 mice. After AD induction, 100 µl (20 µl/cm2) of 0.2% and 0.4% CA phytosome was spread on the dorsal skin and ear of the mice three times a week for four weeks. We evaluated dermatitis severity, histopathological changes, and changes in protein expression by Western blotting for iNOS and COX-2; NF-κB activity was determined by gel electromobility shift assay (EMSA). We also measured TNF-α, IL-1β, and IgE concentration in the blood of AD mice by enzyme-linked immunosorbent assay (ELISA). CA phytosome attenuated the development of PA-induced AD. Histological analysis showed that CA phytosome inhibited hyperkeratosis, proliferation of mast cells, and infiltration of inflammatory cells. Furthermore, CA phytosome treatment inhibited the expression of iNOS and COX-2, activity of NF-κB, and release of TNF-α, IL-1β, and IgE. In addition, CA phytosome (5, 10, and 20 µg/ml) potently inhibited lipopolysaccharide (LPS) (1 µg/ml)-induced NO production as well as iNOS and COX-2 expression in RAW 264.7 macrophage cells. Furthermore, CA phytosome inhibited LPS-induced DNA binding activities of NF-κB, and this was associated with the discontinuation of IκBα degradation and subsequent decreases in the translocation of p65 and p50 into the nucleus. From our data, CA phytosome application, which operates via NF-κB signaling inhibition, seems to be a promising AD treatment.