Chijabyukpi-Tang Inhibits Pro-Inflammatory Cytokines and Chemokines via the Nrf2/HO-1 Signaling Pathway in TNF-α/IFN-γ-Stimulated HaCaT Cells and Ameliorates 2,4-Dinitrochlorobenzene-Induced Atopic Dermatitis-Like Skin Lesions in Mice

Oral Ingestion of Yuzu Seed Oil Suppresses the Development of Atopic Dermatitis-like Skin Lesions in NC/Nga Mice

Long-term oral ingestion of unheated yuzu seed oil in humans reduces lipid peroxides in the blood. Moreover, yuzu seed oil contains limonin, which can induce antioxidant and anti-inflammatory effects by activating the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). Previously, Nrf2 has been shown to reduce atopic dermatitis (AD). Therefore, we hypothesized that ingesting unheated yuzu seed oil can regulate AD through Nrf2. An AD model was established using NC/Nga mice through repeated local exposure to mite antigens. Unheated and purified yuzu seed oil (100 µL/mice) or water (control, 100 µL/mice) was administered orally once a day using a gastric cannula for rodents for 28 days. On day 28, mice in the unheated yuzu seed oil group exhibited significantly lower clinical skin severity scores and ear thickness than those in the purified yuzu seed oil and water groups. Serum histamine levels remained unaltered among the three AD-induced groups. Serum Dermatophagoides farina body (Dfb)-specific immunoglobulin E (IgE) levels were significantly lower in the unheated yuzu seed oil group. Oral ingestion of yuzu seed oil in NC/Nga AD model mice significantly suppressed dermatitis deterioration and decreased serum IgE levels. Clinical trials (n = 41) have already confirmed that unheated yuzu oil is safe for long-term intake, further suggesting its potential use in improving AD symptoms.

Exogenous drugs-induced mouse models of atopic dermatitis

Atopic dermatitis (AD) is an inflammatory skin disease characterized by intense pruritus. AD is harmful to both children and adults, but its pathogenic mechanism has yet to be fully elucidated. The development of mouse models for AD has greatly contributed to its study and treatment. Among these models, the exogenous drug-induced mouse model has shown promising results and significant advantages. Until now, a large amount of AD-related research has utilized exogenous drug-induced mouse models, leading to notable advancements in research. This indicates the crucial significance of applying such models in AD research. These models exhibit diverse characteristics and are highly complex. They involve the use of various strains of mice, diverse types of inducers, and different modeling effects. However, there is currently a lack of comprehensive comparative studies on exogenous drug-induced AD mouse models, which hinders researchers' ability to choose among these models. This paper provides a comprehensive review of the features and mechanisms associated with various exogenous drug-induced mouse models, including the important role of each cytokine in AD development. It aims to assist researchers in quickly understanding models and selecting the most suitable one for further investigation.

Histone deacetylase 3 inhibition alleviates 2,4-dinitrochlorobenzene-induced atopic dermatitis via epigenetically upregulating Nrf2/HO-1 signaling pathway

Atopic dermatitis (AD) is a frequent skin disorder that is associated with immune dysfunction and skin inflammation. Histone deacetylase 3 (HDAC3) possesses strong immune and inflammatory modulatory properties in multiple diseases. However, the role and mechanism of HDAC3 in AD remain unknown. Here, we reported that HDAC3 expression was aberrantly upregulated in 2,4-dinitrochlorobenzene (DNCB)-induced lesional AD skin in mice. Inhibition of HDAC3 by RGFP966 protected against DNCB-induced AD, indicated by improved histological damages, relieved inflammatory and immune dysfunction. Nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) signaling pathway activity in lesional AD skin was significantly decreased and RGFP966 attenuated the decrease. Inhibition of Nrf2/HO-1 signaling pathway via Nrf2 inhibitor ML385 blunted anti-AD effect of RGFP966 in DNCB-treated mice. Mechanistically, RGFP966 promoted Nrf2 expression and upregulated H3K27ac deposition on the promoter region of Nrf2. Collectively, HDAC3 inhibition protects against AD via epigenetically activating Nrf2 transcription to upregulate Nrf2/HO-1 signaling pathway activity. HDAC3 may act as a promising therapeutic target for the treatment of AD.

Resveratrol modulates the Nrf2/NF-κB pathway and inhibits TSLP-mediated atopic march

BACKGROUND

Resveratrol has been found to have anti-inflammatory and anti-allergic properties. The effects of resveratrol on thymic stromal lymphopoietin (TSLP)-mediated atopic march remain unclear.

PURPOSE

To explore the potential role of resveratrol in TSLP-mediated atopic march.

METHODS

The atopic march mouse model was established by topical application of MC903 (a vitamin D3 analog). Following the treatment with resveratrol, airway resistance in mice was discovered by pulmonary function apparatus, and the number of total cells, neutrophils, and eosinophils in bronchoalveolar lavage fluid was counted. The histopathological features of pulmonary and ear skin tissues, inflammation, and cell infiltration were determined by hematoxylin and eosin staining. The messenger RNA (mRNA) levels of TSLP, immunoglobulin E, interleukin (IL)-4, IL-5, and IL-13 were measured by real-time quantitative polymerase chain reaction. The protein expression of nuclear factor kappa B (NF-κB)/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling-associated molecules (p-p65, p65, p-I kappa B kinase alpha (IκBα), IκBα, Nrf2, and TSLP) in lung and ear skin tissues were assessed by Western blot analysis.

RESULTS

Resveratrol attenuated airway resistance and infiltration of total cells, eosinophils, and neutrophils in both lung and ear skin tissues. Resveratrol ameliorates serum inflammatory markers in allergic mice. Moreover, the phosphorylation levels of NF-κB pathway-related proteins were significantly reduced by administration of resveratrol in allergic lung and ear skin tissues. Similarly, the protein expression of TSLP in both lung and ear skin tissues was reduced by resveratrol, and Nrf2, a protector molecule, was increased with resveratrol treatment.

CONCLUSION

Resveratrol attenuates TSLP-reduced atopic march through ameliorating inflammation and cell infiltration in pulmonary and ear skin tissues by inhibiting the abnormal activation of NF-κB signaling pathway.

Phytochemical Investigation of Equisetum arvense and Evaluation of Their Anti-Inflammatory Potential in TNFα/INFγ-Stimulated Keratinocytes

Equisetum arvense L. (Equisetaceae), widely known as 'horsetail', is a perennial plant found extensively across Asia. Extracts of E. arvense have been used in traditional medicine, particularly for the treatment of inflammatory disorders. This study aimed to determine the phytochemical compounds in E. arvense ethanolic extract and their anti-inflammatory properties. Subsequently, we isolated and identified nine secondary metabolites, including kaempferol 3,7-di-O-β-D-glucopyranoside (1), icariside B2 (2), (Z)-3-hexenyl β-D-glucopyranoside (3), luteolin 5-O-β-D-glucopyranoside (4), 4-O-β-D-glucopyranosyl caffeic acid (5), clemastanin B (6), 4-O-caffeoylshikimic acid (7), (7S,8S)-threo-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-4-O-β-D-glucopyranoside (8), and 3-O-caffeoylshikimic acid (9). The chemical structures of the isolated compounds (1-9) were elucidated using HR-ESI-MS data, NMR spectra, and ECD data. Next, the anti-inflammatory effects of the isolates were evaluated in tumor necrosis factor (TNF)α/interferon (IFN)γ-induced HaCaT, a human keratinocyte cell line. Among the isolates, compound 3 showed the highest inhibitory effect on the expression of pro-inflammatory chemokines, followed by compounds 6 and 8. Correspondingly, the preceding isolates inhibited TNFα/IFNγ-induced activation of pro-inflammatory transcription factors, signal transducer and activator of transcription 1, and nuclear factor-κB. Collectively, E. arvense could be employed for the development of prophylactic or therapeutic agents for improving dermatitis.

Ursolic acid ameliorates DNCB-induced atopic dermatitis-like symptoms in mice by regulating TLR4/NF-κB and Nrf2/HO-1 signaling pathways

BACKGROUND

Ursolic acid (UA) is a triterpenoid compound found in natural plants. It has been reported to have anti-inflammatory, antioxidant, and immunomodulatory properties. However, its role in atopic dermatitis (AD) is unknown. This study aimed to evaluate the therapeutic effect of UA in AD mice and explore the underlying mechanisms.

METHODS

Balb/c mice were treated with 2, 4-dinitrochlorobenzene (DNCB) to induce AD-like lesions. During modeling and medication administration, dermatitis scores and ear thickness were measured. Subsequently, histopathological changes, levels of T helper cytokines, and oxidative stress markers levels were evaluated. Immunohistochemistry staining was used to assess changes in the expression of the nuclear factor of kappa B (NF-κB) and NF erythroid 2-related factor 2 (Nrf2). Furthermore, CCK8 assay, reactive oxygen species (ROS) assay, real-time PCR, and western blotting were employed to evaluate the effects of UA on ROS levels, inflammatory mediator production, and the NF-κB and Nrf2 pathways in TNF-α/IFN-γ-stimulated HaCaT cells.

RESULTS

The results showed that UA significantly reduced dermatitis score and ear thickness, effectively inhibited skin proliferation and mast cell infiltration in AD mice, and decreased the expression level of T helper cytokines. Meanwhile, UA improved oxidative stress in AD mice by regulating lipid peroxidation and increasing the activity of antioxidant enzymes. In addition, UA inhibited ROS accumulation and chemokine secretion in TNF-α/IFN-γ-stimulated HaCaT cells. It might exert anti-dermatitis effects by inhibiting the TLR4/NF-κB pathway and activating the Nrf2/HO-1 pathway.

CONCLUSION

Taken together, our results suggest that UA may have potential therapeutic effects on AD and could be further studied as a promising drug for AD treatment.

Review on Extraction, Modification, and Synthesis of Natural Peptides and Their Beneficial Effects on Skin

Peptides, functional nutrients with a size between those of large proteins and small amino acids, are easily absorbed by the human body. Therefore, they are seeing increasing use in clinical medicine and have revealed immunomodulatory and anti-inflammatory properties which could make them effective in healing skin wounds. This review sorted and summarized the relevant literature about peptides during the past decade. Recent works on the extraction, modification and synthesis of peptides were reviewed. Importantly, the unique beneficial effects of peptides on the skin were extensively explored, providing ideas for the development and innovation of peptides and laying a knowledge foundation for the clinical application of peptides.

Network Pharmacology Integrated with Transcriptomics Analysis Reveals Ermiao Wan Alleviates Atopic Dermatitis via Suppressing MAPK and Activating the EGFR/AKT Signaling

Background

Ermiao Wan (EMW) is commonly used to treat atopic dermatitis (AD) in China. However, the pharmacological mechanisms underlying the action of EMW against AD remain unclear.

Purpose

We aimed to determine the mechanisms underlying the effectiveness of EMW in the treatment of AD.

Methods

We evaluated the effect of EMW on AD induced by dinitrochlorobenzene (DNCB) in BALB/C mice. To clarify the key components of EMW in AD treatment, the main components of EMW were identified using HPLC. Serum pharmacochemistry was used to analyze the absorbed ingredients from blood. Based on the phytochemical results, network pharmacology and molecular docking were used to predict the action of EMW. Skin transcriptomic analysis was used to validate the network pharmacology results. RT-qPCR,ELISA, and immunohistochemical were performed to validate the results of skin transcriptomics.

Results

EMW improved the symptoms of AD, with less rashes, less spontaneous scratching, less inflammatory cell infiltration, and fewer allergic reactions. The established HPLC method is simple and reliable. Chlorogenic acid, phellodendrine, magnoflorine, jatrorrhizine, palmatine, berberine, and atractylodin were the key effective ingredients with a high blood concentration. Fifty-seven primary causal targets of EMW against AD were identified. These targets are mainly involved in ErbB signaling pathways including EGFR, AKT1, MAPK8, JUN, MAPK1. Molecular docking showed that EGFR, AKT1, MAPK8, JUN, MAPK1 had good binding force with EMW. In AD mice, EMW regulated the EGFR/AKT signaling through upregulation of Grb2, GAB1, Raf-1, EGFR, and AKT, and downregulation of MAPK1 and JUN, compared to that in the MD group.

Conclusion

EMW could alleviate AD through activating EGFR/AKT signaling and suppressing MAPK. This study provides a theoretical basis for the clinical use of EMW.

Evaluation of the Anti-Atopic Dermatitis Effects of α-Boswellic Acid on Tnf-α/Ifn-γ-Stimulated HaCat Cells and DNCB-Induced BALB/c Mice

Boswellic acids, triterpenoids derived from the genus Boswellia (Burseraceae), are known for their anti-inflammatory and anti-tumor efficacy. Atopic dermatitis is a chronic, non-infectious inflammatory skin disease. However, the effects of α-boswellic acid on atopic dermatitis have not been studied. Therefore, in this study we examined the expression level of pro-inflammatory cytokines, histopathological analysis, and physiological data from BALB/c mice with atopic-like dermatitis induced by 2,4-dinitrochlorobenzene and TNF-α/IFN-γ-stimulated HaCaT cells to better understand the agent’s anti-atopic dermatitis efficacy. First, we found that α-boswellic reduced the epidermal thickening, mast cell numbers, and dermal infiltration of 2,4-dinitrochlorobenzene-induced atopic-like dermatitis in BALB/c mice. Furthermore, we also found that α-boswellic acid can restore transepidermal water loss and skin reddening in mice. In human keratinocytes inflamed by TNF-α/IFN-γ, α-boswellic acid inhibited MAP kinase activation and showed a reduction in NF-κB nuclear translocation. Finally, α-boswellic acid can reduce the expression level of cytokines (IL-1β, IL-6, and IL-8) following the stimulation of TNF-α/IFN-γ in HaCaT cells. Taken together, our study suggests that α-boswellic acids are a potential component for the development of anti-atopic dermatitis drugs.

Encapsulated saponin by ferritin nanoparticles attenuates the murine pneumococcal pneumonia

Streptococcus pneumonia is classified as a gram-positive bacterial pathogen that causes asymptomatic or symptomatic respiratory infections. This study aimed to evaluate the effects of designed encapsulated saponin by ferritin nanoparticles in the healing progression of experimental bacterial pneumonia. The saponin encapsulated by ferritin followed the disassembly-reassembly process. Pneumonia was induced by the preparation of Streptococcus pneumonia. A total of 50 NMRI mice were divided into control, pneumonia, pneumonia + ferritin, pneumonia + saponin, and pneumonia + encapsulated saponin by ferritin nanoparticles (Nano Saponin) groups. ELISA, Real-time PCR, and Western blotting were used to measure sera IL-4 level, tumor necrosis factor-alpha (Tnf-α), and protein cyclooxygenase-2 (COX-2) gene expression, respectively. COX-2 protein expression, Tnf-α gene expression, and serum levels of IL-4 reduced compared to the pneumonia group. The histopathology results revealed that the rates of inflammation, mucus secretion, pulmonary hemorrhage, thickening of the alveoli wall, and secretion of inflammatory cells were lower in the Nano Saponin group than in the other groups. This study suggests that Glycyrrhiza glabra saponin and encapsulated saponin by ferritin nanoparticles oral consumption with anti-Tnf-α effect besides decreasing protein expression of COX-2 allows mice with pneumonia to recover.

Secoisolariciresinol diglucoside-derived metabolite, enterolactone, attenuates atopic dermatitis by suppressing Th2 immune response

Atopic dermatitis (AD) is a severe inflammatory skin disease caused by a combination of genetic, immune, and environmental factors. Intestinal microbiome disorders and changes in the immune microenvironment are associated with AD. We observed that gut bacterial metabolite enterolactone (ENL) was significantly reduced in AD model mice. Notably, patients with early childhood-onset AD exhibited decreased sera ENL level compared to the healthy controls, and the ENL level was negatively correlated with the SCORAD index. Secoisolariciresinol-diglycoside (SDG) is a natural dietary lignan of flaxseeds that can be converted by intestinal bacteria to ENL. Repeated applications of 2,4-dinitrochlorobenzene (DNCB) were performed on the ear and dorsal skin of mice to induce AD-like symptoms and skin lesions. Oral administration of SDG significantly decreased serum IgE levels and limited skin inflammation in the DNCB-induced AD mice. In addition, SDG treatment strongly limited the Th2 responses in AD mice. Moreover, we demonstrated that the IL-4 production was significantly suppressed by ENL under Th2 polarization conditions via the JAK-STAT6 signaling pathway in a concentration-dependent manner. We concluded that SDG and its derived metabolite ENL ameliorated AD development by reducing the Th2 immune response. These results suggested that SDG and ENL might be exploited as potential therapeutic candidates for AD treatment.

Therapeutic effects of myricetin on atopic dermatitis in vivo and in vitro

BACKGROUND

Myricetin (Myr) is a flavonoid compound that exist widely in many natural plants. Myr has been proven to have multiple biological functions, including immunomodulatory and anti-inflammatory effects.

PURPOSE

In this study, we investigated the therapeutic effect of Myr on calcipotriol (MC903) induced atopic dermatitis (AD) mouse model and tumor necrosis factor (TNF)-α/interferon (IFN)-γ stimulated human immortal keratinocyte line (HaCaT) in vivo and in vitro.

METHODS

MC903 was applied topically to the left ears of mice to establish AD mouse model. After the AD model established successfully, the cream base, dexamethasone (DEX) cream or Myr cream were applied on the lesions of mice for 8 days. Through measuring ear thickness and scoring dermatitis severity, we evaluated the therapeutic effect of Myr, the draining lymph nodes (DLNs) and ears of the mice were collected for mechanistic study. In addition, TNF-α and IFN-γ-activated HaCaT cells were used to investigate the underlying mechanism.

RESULTS

Our data demonstrated that Myr alleviated the symptoms of AD by exerting anti-inflammatory and anti-allergic functions in vivo. We found that Myr treatment suppressed ear swelling and IgE level in the serum, reduced the infiltration of mast cells in skin lesions, decreased expressions of thymus and activation regulated chemokine (TARC), IL-4, IFN-γ and thymic stromal lymphopoietin (TSLP) in ear lesions, increased the expressions of filaggrin (FLG). Furthermore, our experimental results demonstrated that Myr down-regulated the mRNA expressions of T-bet and GATA-3 in DLNs. In vitro, Myr treatment decreased MDC and TARC expressions in IFN-γ and TNF-α-induced HaCaT cells by blocking the NF-κB and STAT1 signal pathway.

CONCLUSION

The present study is the first to investigate the anti-atopic effects of Myr. Our findings suggested the therapeutic effects of Myr against MC903-induced AD-like skin lesions in mice. Therefore, Myr may be a potential therapeutic agent for AD.

The Role of KEAP1-NRF2 System in Atopic Dermatitis and Psoriasis

The Kelch-like erythroid cell-derived protein with cap‘n’collar homology-associated protein 1 (KEAP1)-nuclear factor erythroid-2-related factor 2 (NRF2) system, a thiol-based sensor-effector apparatus, exerts antioxidative and anti-inflammatory effects and maintains skin homeostasis. Thus, NRF2 activation appears to be a promising treatment option for various skin diseases. However, NRF2-mediated defense responses may deteriorate skin inflammation in a context-dependent manner. Atopic dermatitis (AD) and psoriasis are two common chronic inflammatory skin diseases caused by a defective skin barrier, dysregulated immune responses, genetic predispositions, and environmental factors. This review focuses on the role of the KEAP1-NRF2 system in the pathophysiology of AD and psoriasis and the therapeutic approaches that utilize this system.

Spatholobus suberectus Dunn Water Extract Ameliorates Atopic Dermatitis–Like Symptoms by Suppressing Proinflammatory Chemokine Production In Vivo and In Vitro

S. patholobus suberectus Dunn, a traditional Chinese herbal medicine, has various pharmacological activities, such as anti-inflammatory properties. However, to the best of our knowledge, its therapeutic effect on atopic dermatitis (AD) has not been investigated. In this study, we explored the effect of S. suberectus Dunn water extract (SSWex) on AD in vivo and in vitro. In Dermatophagoides farina extract (DfE)–treated NC/Nga mice, the oral administration of SSWex alleviated AD-like symptoms, such as ear thickness, dermatitis score, epidermal thickness, immune cell infiltration, and levels of AD-related serum parameters (immunoglobulin E, histamine, and proinflammatory chemokines). In HaCaT cells, the production of proinflammatory chemokines induced by interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) was inhibited by SSWex pretreatment. SSWex treatment inhibited the phosphorylation of mitogen-activated protein kinase and activation and translocation of transcriptional factors, such as signal transducer and activator of transcription 1 and nuclear factor kappa B in IFN-γ/TNF-α–stimulated HaCaT cells. These results indicate that SSWex may be developed as an efficient therapeutic agent for AD.

Hepatoprotective Role of 4-Octyl Itaconate in Concanavalin A-Induced Autoimmune Hepatitis

4-Octyl itaconate (OI) is a novel anti-inflammatory metabolite that exerts protective effects in many various disease models. However, its function in autoimmune hepatitis- (AIH-) associated hepatic injury has not been investigated. In this study, we successfully used concanavalin A (Con A) to establish an AIH-associated liver injury model. Furthermore, we investigated the effect of OI in Con A-induced liver injury and found that OI mitigated Con A-induced histopathological damage. OI administration reduced serum levels of alanine transaminase and aspartate transaminase in Con A-treated mice and attenuated the infiltration of macrophages induced by Con A. Moreover, OI effectively inhibited the expression of proinflammatory cytokines including interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), and IL-1β induced by Con A. Furthermore, OI decreased hepatocyte apoptosis and malondialdehyde levels and increased the reduced glutathione/oxidized glutathione ratio in the Con A-induced liver injury model. In addition, we found that OI inhibited Con A-induced hepatocyte apoptosis in vitro, while Nrf2 deletion eliminated this effect. Furthermore, we administrated the Nrf2 inhibitor ML385 in OI+Con A-treated mice and found that ML385 eliminated the protective effect of OI in vivo. In addition, OI inhibited Con A-induced activation of nuclear factor-kappa B (NF-𝜅B) and the expression of proinflammatory cytokines in macrophages. Therefore, OI protected mice from Con A-induced liver damage and may be associated with Nrf2 activation and NF-𝜅B inhibition. Finally, our study revealed that OI inhibited TNF-α, or supernatants from Con A-treated RAW264.7 cells induced hepatocyte apoptosis. In conclusion, our study indicated that OI alleviated Con A-induced hepatic damage by reducing inflammatory response, oxidative stress, and apoptosis.

Algal Lipids as Modulators of Skin Disease: A Critical Review

The prevalence of inflammatory skin diseases continues to increase with a high incidence in children and adults. These diseases are triggered by environmental factors, such as UV radiation, certain chemical compounds, infectious agents, and in some cases, people with a genetic predisposition. The pathophysiology of inflammatory skin diseases such as psoriasis or atopic dermatitis, but also of skin cancers, is the result of the activation of inflammation-related metabolic pathways and the overproduction of pro-inflammatory cytokines observed in in vitro and in vivo studies. Inflammatory skin diseases are also associated with oxidative stress, overproduction of ROS, and impaired antioxidant defense, which affects the metabolism of immune cells and skin cells (keratinocytes and fibroblasts) in systemic and skin disorders. Lipids from algae have been scarcely applied to modulate skin diseases, but they are well known antioxidant and anti-inflammatory agents. They have shown scavenging activities and can modulate redox homeostasis enzymes. They can also downmodulate key inflammatory signaling pathways and transcription factors such as NF-κB, decreasing the expression of pro-inflammatory mediators. Thus, the exploitation of algae lipids as therapeutical agents for the treatment of inflammatory skin diseases is highly attractive, being critically reviewed in the present work.

Ethnobotanical Survey on Skin Whitening Prescriptions of Traditional Chinese Medicine in Taiwan

The increasing interest and demand for skin whitening products globally, particularly in Asia, have necessitated rapid advances in research on skin whitening products used in traditional Chinese medicine (TCM). Herein, we investigated 74 skin whitening prescriptions sold in TCM pharmacies in Taiwan. Commonly used medicinal materials were defined as those with a relative frequency of citation (RFC) > 0.2 and their characteristics were evaluated. Correlation analysis of commonly used medicinal materials was carried out to identify the core component of the medicinal materials. Of the purchased 74 skin whitening prescriptions, 36 were oral prescriptions, 37 were external prescriptions, and one prescription could be used as an oral or external prescription. After analysis, 90 traditional Chinese medicinal materials were obtained. The Apiaceae (10%; 13%) and Leguminosae (9%; 11%) were the main sources of oral and external medicinal materials, respectively. Oral skin whitening prescriptions were found to be mostly warm (46%) and sweet (53%), while external skin whitening prescriptions included cold (43%) and bitter (29%) medicinal materials. Additionally, mainly tonifying and replenishing effects of the materials were noted. Pharmacological analysis indicated that these medicinal materials may promote wound healing, treat inflammatory skin diseases, or anti-hyperpigmentation. According to the Spearman correlation analysis on interactions among medicinal materials with an RFC > 0.2 in the oral skin whitening prescriptions, Paeonia lactiflora Pall. (white) and Atractylodes macrocephala Koidz. showed the highest correlation (confidence score = 0.93), followed by Ziziphus jujuba Mill. (red) and Astragalus propinquus Schischkin (confidence score = 0.91). Seven medicinal materials in external skin whitening prescriptions with an RFC > 0.2, were classified as Taiwan qī bái sàn (an herbal preparation), including Angelica dahurica (Hoffm.) Benth. & Hook. f. ex Franch. & Sav., Wolfiporia extensa (Peck) Ginns, Bletilla striata (Thunb.) Rchb. f., Atractylodes macrocephala Koidz., Ampelopsis japonica (Thunb.) Makino, Paeonia lactiflora Pall. (white), and Bombyx mori Linnaeus. Skin whitening prescriptions included multiple traditional Chinese medicinal materials. Despite the long history of use, there is a lack of studies concerning skin whitening products, possibly due to the complex composition of traditional Chinese medicine. Further studies are required to assess the efficacy and safety of these traditional Chinese medicinal materials for inclusion in effective, safe, and functional pharmacological products.

Anti-Inflammatory Effects of Metabolites from Antarctic Fungal Strain Pleosporales sp. SF-7343 in HaCaT Human Keratinocytes

Chemical investigation of the Antarctic fungi Pleosporales sp. SF-7343 revealed four known secondary fungal metabolites: alternate C (1), altenusin (2), alternariol (3), and altenuene (4). The compound structures were identified primarily by NMR and MS analyses. Atopic dermatitis, an inflammatory disease, is driven by the abnormal activation of T helper (Th) 2 cells and barrier dysfunction. We attempted to identify the anti-inflammatory components of SF-7343. Initial screening showed that compounds 1 and 3 inhibited the secretion of interleukin-8 and -6 in tumor necrosis factor-α/interferon-γ-treated HaCaT cells, and these compounds also showed inhibitory effects on CCL5 and CCL22. Compounds 1 and 3 also downregulated the protein expression levels of intercellular adhesion molecule-1 and upregulated the expression of filaggrin and involcurin. The mechanism study results showed that compounds 1 and 3 inhibited nuclear translocation of nuclear factor-kappa B p65 and the phosphorylation of STAT1 and STAT3. Compound 1, but not compound 3, significantly promoted the expression of heme oxygenase (HO)-1. The effects of compound 1 were partly reversed by co-treatment with a HO-1 inhibitor, tin protoporphyrin IX. Taken together, this study demonstrates the potential value of Antarctic fungal strain SF-7343 isolates as a bioresource for bioactive compounds to prevent skin inflammation.

UV-Irradiation- and Inflammation-Induced Skin Barrier Dysfunction Is Associated with the Expression of Olfactory Receptor Genes in Human Keratinocytes

Olfactory receptors (ORs) have diverse physiological roles in various cell types, beyond their function as odorant sensors in the olfactory epithelium. These previous findings have suggested that ORs could be diagnostic markers and promising therapeutic targets in several pathological conditions. In the current study, we sought to characterize the changes in the expression of ORs in the HaCaT human keratinocytes cell line exposed to ultraviolet (UV) light or inflammation, well-recognized stimulus for skin barrier disruption. We confirmed that major olfactory signaling components, including ORs, GNAL, Ric8b, and adenylate cyclase type 3, are highly expressed in HaCaT cells. We have also demonstrated that the 12 ectopic ORs detectable in HaCaT cells are more highly expressed in UV-irradiated or inflamed conditions than in normal conditions. We further assessed the specific OR-mediated biological responses of HaCaT cells in the presence of known odorant ligands of ORs and observed that specific ligand-activated ORs downregulate skin barrier genes in HaCaT cells. This study shows the potential of OR as a marker for skin barrier abnormalities. Further research is needed to explore how OR is implicated in the development and progression of barrier dysfunction.

Phellodendron amurense Extract Protects Human Keratinocytes from PM2.5-Induced Inflammation via PAR-2 Signaling

Dietary supplement and personal care products aiming to provide protection from air pollution have been of great interest for decades. Epidemiology demonstrated that PM10 and PM2.5 particulate matter (PM) are an actual threat to public health worldwide, but the detailed processes of how these particles attack the cells are not fully understood. Here, we report that the measurement of intracellular calcium concentration ([Ca²⁺]i) using human respiratory or skin cells can illustrate pollutant challenges by triggering Ca²⁺ influx in these cells. This signal was generated by proteinase-activated receptor-2 (PAR-2), confirmed by competition analyses, and Phellodendron amurense bark extract (PAE), a traditional medicine, was able to control the response and expression of PAR-2. Increase in proinflammatory cytokines and decrease in cell adhesion components could suggest a severe damage status by air pollutants and protection by PAE. Finally, we identified 4-O-feruloylquinic acid (FQA), an active compound of PAE, showing the same effects on Ca²⁺ influx and PAR-2 regulation. The results presented here should help understand the underlying mechanism of PM insults and the beneficial effect of standardized PAE as dietary supplement or cosmetical ingredient.