Atopic dermatitis: Role of the skin barrier, environment, microbiome, and therapeutic agents

Portable Arduino-Based Multi-Sensor Device (SBEDAD): Measuring the Built Environment in Street Cycling Spaces

The built environment's impact on human activities has been a hot issue in urban research. Compared to motorized spaces, the built environment of pedestrian and cycling street spaces dramatically influences people's travel experience and travel mode choice. The streets' built environment data play a vital role in urban design and management. However, the multi-source, heterogeneous, and massive data acquisition methods and tools for the built environment have become obstacles for urban design and management. To better realize the data acquisition and for deeper understanding of the urban built environment, this study develops a new portable, low-cost Arduino-based multi-sensor array integrated into a single portable unit for built environment measurements of street cycling spaces. The system consists of five sensors and an Arduino Mega board, aimed at measuring the characteristics of the street cycling space. It takes air quality, human sensation, road quality, and greenery as the detection objects. An integrated particulate matter laser sensor, a light intensity sensor, a temperature and humidity sensor, noise sensors, and an 8K panoramic camera are used for multi-source data acquisition in the street. The device has a mobile power supply display and a secure digital card to improve its portability. The study took Beijing as a sample case. A total of 127.97 G of video data and 4794 Kb of txt records were acquired in 36 working hours using the street built environment data acquisition device. The efficiency rose to 8474.21% compared to last year. As an alternative to conventional hardware used for this similar purpose, the device avoids the need to carry multiple types and models of sensing devices, making it possible to target multi-sensor data-based street built environment research. Second, the device's power and storage capabilities make it portable, independent, and scalable, accelerating self-motivated development. Third, it dramatically reduces the cost. The device provides a methodological and technological basis for conceptualizing new research scenarios and potential applications.

Awareness and knowledge of sun exposure and use of sunscreen among adults in Aseer region, Saudi Arabia

Background

Excessive sun exposure and inadequate sunscreen use can lead to skin cancer and other harmful effects on the skin, eyes, and immune system.

Purpose

This observational cross-sectional study aimed to assess awareness and knowledge of sun exposure and sunscreen use among adults in the Aseer region, Saudi Arabia. This study also focused on evaluating the risks of skin cancer and participants' sun-protective attitudes and practices.

Methods

A population-based cross-sectional study was conducted among adults in the Aseer region, Saudi Arabia. Data were collected using a questionnaire from November 2022 to January 2023 that assessed participants' knowledge, practices, and beliefs regarding sun exposure and sunscreen use. A total of 400 participants were selected for the study. Approval for the study was granted by the Local Research Ethics Committee of the University of Bisha, Saudi Arabia.

Results

The results revealed that (59.8 %) of the participants were female, while (40.3 %) were male. Regarding age, the majority fell within the 26-35 age range (37.5 %), with (16.0 %) of participants using sunscreen regularly, with a total of (74.0 %) of participants using sunscreen. Men exhibited a higher prevalence of negative attitudes towards sun protection, while women demonstrated more favourable sun protection practices. In addition, (1.25 %) of the participants had skin cancer in the past; (81.0 %) of participants agreed that skin cancer could cause death, while (19.0 %) were unsure of the effects of skin cancer. Moreover, the results indicated that sun exposure had a significant positive effect on awareness levels (p < 0.05), indicating that increased sun exposure was associated with higher awareness of the harmful effects of the sun. Additionally, awareness level significantly positively affected sunscreen use (p < 0.01), suggesting that individuals with higher awareness were more likely to use sunscreen.

Conclusion

There was an average awareness of sun exposure and its detrimental effects. In addition, a significant portion of the population demonstrates proactive measures to minimize sunlight exposure. However, sunscreen usage among Saudi adults was low despite having knowledge and awareness. Future research must enhance sun protection practices and reduce sun-related skin damage in the Aseer region.

Skin Barrier in Atopic Dermatitis

A compromised permeability barrier is a hallmark of atopic dermatitis (AD). Localized to the outermost skin layer, the stratum corneum (SC) is critically dependent on terminal differentiation of epidermal keratinocytes, which transform into protein-rich corneocytes surrounded by extracellular lamellae of unique epidermal lipids, conferring permeability barrier function. These structures are disrupted in AD. A leaky barrier is prone to environmental insult, which in AD elicits type 2-dominant inflammation, in turn resulting in a vicious cycle further impairing the SC structure. Therapies directed at enforcing SC structure and anti-inflammatory strategies administered by topical and systemic route as well as UV therapy have differential effects on the permeability barrier. The expanding armamentarium of therapeutic modalities for AD treatment warrants optimization of their effects on permeability barrier function.

Ozonated Sunflower Oil (OSO) Alleviates Inflammatory Responses in Oxazolone-Induced Atopic Dermatitis (AD)-Like Mice and LPS-Treated RAW 264.7 Cells

Ozone, a highly reactive oxidant molecule, is widely used as a complementary therapy for various skin diseases, including wound healing, pressure ulcers, diabetic foot, and infections. However, there is limited research on the effectiveness of ozone for atopic dermatitis (AD). Ozonated sunflower oil (OSO) is an active ingredient obtained from partially ozonated sunflower oil (SO). OSO markedly reduced the LPS-induced increase in IL-1β and nitric oxide (NO) levels in RAW 264.7 mouse macrophage cells. Oxazolone (OXZ) was applied to hairless mice to induce AD-like skin symptoms and immune response. OSO significantly alleviated the OXZ-induced increases in the number of infiltrating mast cells, epidermal thickness, AD symptoms, thymic stromal lymphopoietin (TSLP), and filaggrin, as well as the serum levels of NO, IgE, IL-1β, and TNF-α. Furthermore, OSO inhibited the IL-4/STAT3/MAPK pathway and the expression of NF-κB. Our results suggest that OSO treatment could relieve AD-mediated skin damage through its anti-inflammatory and antioxidant activities. Therefore, it can be used as a therapeutic agent against AD-related skin diseases.

Filaggrin loss-of-function variants are associated with atopic dermatitis phenotypes in a diverse, early-life prospective cohort

Loss-of-function (LoF) variants in the filaggrin (FLG) gene are the strongest known genetic risk factor for atopic dermatitis (AD), but the impact of these variants on AD outcomes is poorly understood. We comprehensively identified genetic variants through targeted region sequencing of FLG in children participating in the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children cohort. Twenty FLG LoF variants were identified, including 1 novel variant and 9 variants not previously associated with AD. FLG LoF variants were found in the cohort. Among these children, the presence of 1 or more FLG LoF variants was associated with moderate/severe AD compared with those with mild AD. Children with FLG LoF variants had a higher SCORing for Atopic Dermatitis (SCORAD) and higher likelihood of food allergy within the first 2.5 years of life. LoF variants were associated with higher transepidermal water loss (TEWL) in both lesional and nonlesional skin. Collectively, our study identifies established and potentially novel AD-associated FLG LoF variants and associates FLG LoF variants with higher TEWL in lesional and nonlesional skin.

Nanotechnology strategies to address challenges in topical and cellular delivery of siRNAs in skin disease therapy

Gene therapy is one of the most advanced therapies in current medicine. In particular, interference RNA-based therapy by small interfering RNA (siRNA) has gained attention in recent years as it is a highly versatile, selective and specific therapy. In dermatological conditions, topical delivery of siRNA offers numerous therapeutic advantages, mainly by inhibiting the expression of target transcripts directly in the skin. However, crossing the stratum corneum and overcoming intracellular barriers is an inherent challenge. Substantial efforts by scientists have moved towards the use of multimodal and multifunctional nanoparticles to overcome these barriers and achieve greater bioavailability in their site of action, the cytoplasm. In this review the most innovative strategies based on nanoparticle and physical methods are presented, as well as the design principles and the main factors that contribute to the performance of these systems. This review also highlights the synergistic contributions of medicine, nanotechnology, and molecular biology to advancing translational research into siRNA-based therapeutics for skin diseases.

Recommendations on the Use of Moisturizing Products Prepared by Spanish Dermatologists Using the Delphi Method

BACKGROUND AND OBJECTIVE

Moisturizing products are widely used in conditions affecting skin hydration. However, the lack of scientific evidence leads to discrepancies and great variability in the recommendations used by different health professionals. The aim of this consensus document is to generate recommendations based on the evidence and experience of dermatologists to unify and facilitate the use of moisturizing products in the routine clinical practice.

MATERIALS AND METHODS

A 49-statement questionnaire on moisturizing products was prepared and, then, arranged in 5 blocks: 1) concept; 2) characteristics, 3) frequency and quantity, 4) product use and areas of application, and 5) special populations. Twenty-two expert dermatologists in the management of patients with eczema answered to the survey using a 2-round Delphi methodology (adding an item on the 2nd round).

RESULTS

Consensus was reached on 27 statements (54%), most (n=23) via agreement. The highest level of agreement was reached in the blocks on quantity, product use and areas of application (77.8%), followed by the blocks on characteristics (73%) and frequency (62.5%). Regarding the blocks on concept and special populations, the level of consensus on the items proposed was 37.5% and 10%, respectively. Consensus on the use of emollients for xeroderma (71%) was higher vs atopic dermatitis (64%) and inflamed skin (33.3%).

CONCLUSIONS

Consensus recommendations can help all prescribers and improve the available evidence regarding their use.

The epidermal lipid-microbiome loop and immunity: Important players in atopic dermatitis

BACKGROUND

The promotion of epidermal barrier dysfunction is attributed to abnormalities in the lipid-microbiome positive feedback loop which significantly influences the imbalance of the epithelial immune microenvironment (EIME) in atopic dermatitis (AD). This imbalance encompasses impaired lamellar membrane integrity, heightened exposure to epidermal pathogens, and the regulation of innate and adaptive immunity. The lipid-microbiome loop is substantially influenced by intense adaptive immunity which is triggered by abnormal loop activity and affects the loop's integrity through the induction of atypical lipid composition and responses to dysregulated epidermal microbes. Immune responses participate in lipid abnormalities within the EIME by downregulating barrier gene expression and are further cascade-amplified by microbial dysregulation which is instigated by barrier impairment.

AIM OF REVIEW

This review examines the relationship between abnormal lipid composition, microbiome disturbances, and immune responses in AD while progressively substantiating the crosstalk mechanism among these factors. Based on this analysis, the "lipid-microbiome" positive feedback loop, regulated by immune responses, is proposed.

KEY SCIENTIFIC CONCEPTS OF REVIEW

The review delves into the impact of adaptive immune responses that regulate the EIME, driving AD, and investigates potential mechanisms by which lipid supplementation and probiotics may alleviate AD through the up-regulation of the epidermal barrier and modulation of immune signaling. This exploration offers support for targeting the EIME to attenuate AD.

Dietary Interventions in Atopic Dermatitis: A Comprehensive Scoping Review and Analysis

BACKGROUND

This scoping review aims to critically assess gaps in the current literature on atopic dermatitis (AD) by evaluating the overall effectiveness of dietary interventions. Through a comprehensive analysis that follows the Preferred Reporting Item for Systematic Review and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines, we conducted a thorough search on the Web of Science database in May 2023 using specific search strategies to identify all relevant studies on the research topic.

SUMMARY

A total of 104 full-text articles were included for review. Our synthesis identified seven notable categories of dietary interventions for AD, showcasing the diversity of interventions utilized. This includes vitamin supplementation, probiotic and prebiotic supplementation, dietary fat, biological compounds, foods from natural sources, major nutrients, and diet-related approaches. Further analyses stratified by targeted populations revealed a predominant focus on pediatrics, particularly in probiotic supplementation, and on adults, with an emphasis on vitamin D and E supplementation.

KEY MESSAGES

Despite most dietary interventions demonstrating overall effectiveness in improving AD severity and its subjective symptoms, several significant gaps were identified. There was a scarcity of studies on adults and whole-diet interventions, a prevalence of short-term interventions, heterogeneity in study outcomes, designs, and population, occasional disparity between statistical significance and clinical relevance, and a lack of a comprehensive multidisciplinary approach. Nonetheless, these findings offer valuable insights for future AD research, guiding additional evidence-driven dietary interventions and informing healthcare professionals, researchers, and individuals, advancing both understanding and management of AD.

Biosignatures of defective sebaceous gland activity in sebum-rich and sebum-poor skin areas in adult atopic dermatitis

Atopic dermatitis (AD) is a composite disease presenting disruption of the skin permeability barrier (SPB) in the stratum corneum (SC). Recent evidence supports derangement of the sebaceous gland (SG) activity in the AD pathomechanisms. The objective of this study was to delineate profiles of both sebaceous and epidermal lipids and of aminoacids from SG-rich (SGR) and SG-poor (SGP) areas in AD. Both sebum and SC were sampled from SGR areas, while SC was sampled also from SGP areas in 54 adult patients with AD, consisting of 34 and 20 subjects, respectively with and without clinical involvement of face, and in 44 age and sex-matched controls. Skin biophysics were assessed in all sampling sites. Disruption of the SBP was found to be associated with dysregulated lipidome. Abundance of sapienate and lignocerate, representing, respectively, sebum and the SC type lipids, were decreased in sebum and SC from both SGR and SGP areas. Analogously, squalene was significantly diminished in AD, regardless the site. Extent of lipid derangement in SGR areas was correlated with the AD severity. The abundance of aminoacids in the SC from SGR areas was altered more than that determined in SGP areas. Several gender-related differences were found in both controls and AD subgroups. In conclusion, the SG activity was differently compromised in adult females and males with AD, in both SGR and SGP areas. In AD, alterations in the aminoacidome profiles were apparent in the SGR areas. Lipid signatures in association with aminoacidome and skin physical properties may serve the definition of phenotype clusters that associate with AD severity and gender.

Eradication of skin microbiota restores cytokine production and release in polymorphic light eruption

Polymorphic light eruption (PLE) has been mechanistically linked to cytokine abnormalities. Emerging preclinical evidence posits the skin microbiome as a critical modulator of ultraviolet (UV)-induced cytokine expression, thereby influencing subsequent immune responses. This intricate relationship remains underexplored in the context of PLE. Hence, we investigated the differential responses between disinfected and non-disinfected skin following both single and repetitive exposures to solar-simulated UV radiation in patients with PLE. An experimental, half-body pilot study was conducted involving six PLE patients and 15 healthy controls. Participants' skin was exposed to single and multiple doses of solar-simulated UV radiation, both in disinfected and in non-disinfected skin areas. The co-primary outcomes were PLE score and cytokine expression in blister fluid analysed through OLINK proteomic profiling. Secondary outcomes were erythema, pigmentation, induction of apoptotic cells in vacuum-generated suction blisters, and density of infiltrate in skin biopsies of PLE patients. Among the 71 cytokines analysed, baseline expression levels of 20 specific cytokines-integral to processes such as apoptosis, inflammation, immune cell recruitment, cellular growth, and differentiation-were significantly impaired in PLE patients compared with healthy controls. Notably, skin disinfection reversed the observed cytokine imbalances following a single UV exposure at the minimal erythema dose (MED) level and exhibited even more pronounced effects after multiple UV exposures. However, no significant differences were evident in PLE score, erythema, pigmentation, or rates of apoptotic cell induction upon UV radiation. These findings provide evidence for UV-driven cytokine regulation by the skin microbiota and imply microbiome involvement in the PLE immune response.

Resident memory T cells in nonlesional skin and healed lesions of patients with chronic inflammatory diseases: Appearances can be deceptive

Tissue-resident memory T (TRM) cells serve as a first line of defense in peripheral tissues to protect the organism against foreign pathogens. However, autoreactive TRM cells are increasingly implicated in autoimmunity, as evidenced in chronic autoimmune and inflammatory skin conditions. This highlights the need to characterize their phenotype and understand their role for the purpose of targeting them specifically without affecting local immunity. To date, the investigation of TRM cells in human skin diseases has focused mainly on lesional tissues of patients. Accumulating evidence suggests that self-reactive TRM cells are still present in clinically healed lesions of patients and play a role in disease flares, but TRM cells also populate skin that is apparently normal. This review discusses the ontogeny of TRM cells in the skin as well as recent insights regarding the presence of self-reactive TRM cells in both clinically healed skin and nonlesional skin of patients with autoimmune and inflammatory skin conditions, with a particular focus on psoriasis, atopic dermatitis, and vitiligo.

The cross-linking between DNA damage, oxidative stress and epidermal barrier in keratinocytes after exposure to particulate matters and carbon black

As the largest organ, the skin provides the first line of defence against environmental pollutants. Different pollutants have varied damage to the skin due to their own physical-chemical properties. A previous epidemiological study by our team revealed that eczema was positively correlated with different air pollutants. However, the mechanism of action from different pollutants on the skin is less known. In this work, the differences among the genotoxicity, intracellular reactive oxygen species, and barrier-related parameters caused by two kinds of air pollutants, that is, S1650b and carbon black (CB) were investigated by Western blot, TUNEL, comet assay and RNA-sequences. The results indicated that both S1650b and CB caused DNA damage of keratinocytes. With the content of lipophilic polycyclic aromatic hydrocarbons (PAH), S1650b leaked into the keratinocytes easily, which activated the aromatic hydrocarbon receptor (AhR) in keratinocytes, leading to worse damage to barrier-related proteins than CB. And CB-induced higher intracellular ROS than S1650b due to the smaller size which make it enter the keratinocytes easier. RNA-sequencing results revealed that S1650b and CB both caused DNA damage of keratinocytes, and the intervention of S1650b significantly upregulated AhR, cytochrome oxidase A1 and B1 (CYP1A1 and CYP1B1) genes, while the results showed oppositely after CB intervention. The mechanism of keratinocyte damage caused by different air particle pollutants in this study will help to expand our understanding on the air pollutant-associated skin disease at cell levels.

Nanotopology-Enabled On-Site Pathogen Detection for Managing Atopic Dermatitis

Atopic dermatitis (AD), a prevalent skin condition often complicated by microbial infection, poses a significant challenge in identifying the responsible pathogen for its effective management. However, a reliable, safe tool for pinpointing the source of these infections remains elusive. In this study, a novel on-site pathogen detection that combines chemically functionalized nanotopology with genetic analysis is proposed to capture and analyze pathogens closely associated with severe atopic dermatitis. The chemically functionalized nanotopology features a 3D hierarchical nanopillar array (HNA) with a functional polymer coating, tailored to isolate target pathogens from infected skin. This innovative nanotopology demonstrates superior pathogenic capture efficiency, favorable entrapment patterns, and non-cytotoxicity. An HNA-assembled stick is utilized to directly retrieve bacteria from infected skin samples, followed by extraction-free quantitative loop-mediated isothermal amplification (direct qLAMP) for validation. To mimic human skin conditions, porcine skin is employed to successfully capture Staphylococcus aureus, a common bacterium exacerbating AD cases. The on-site detection method exhibits an impressive detection limit of 103 cells mL-1 . The HNA-assembled stick represents a promising tool for on-site detection of bacteria associated with atopic dermatitis. This innovative approach enables to deepen the understanding of AD pathogenesis and open avenues for more effective management strategies for chronic skin conditions.

Involvement and repair of epithelial barrier dysfunction in allergic diseases

The epithelial barrier serves as a critical defense mechanism separating the human body from the external environment, fulfilling both physical and immune functions. This barrier plays a pivotal role in shielding the body from environmental risk factors such as allergens, pathogens, and pollutants. However, since the 19th century, the escalating threats posed by environmental pollution, global warming, heightened usage of industrial chemical products, and alterations in biodiversity have contributed to a noteworthy surge in allergic disease incidences. Notably, allergic diseases frequently exhibit dysfunction in the epithelial barrier. The proposed epithelial barrier hypothesis introduces a novel avenue for the prevention and treatment of allergic diseases. Despite increased attention to the role of barrier dysfunction in allergic disease development, numerous questions persist regarding the mechanisms underlying the disruption of normal barrier function. Consequently, this review aims to provide a comprehensive overview of the epithelial barrier's role in allergic diseases, encompassing influencing factors, assessment techniques, and repair methodologies. By doing so, it seeks to present innovative strategies for the prevention and treatment of allergic diseases.

Emerging Role of the IL-36/IL-36R Axis in Multiple Inflammatory Skin Diseases

IL-36 is a most recent member of the IL-1 cytokine family, primarily expressed at barrier sites of the body such as the skin, lungs, and intestine. It plays a vital role in inflammation and is implicated in the development of various cutaneous; intestinal; and pulmonary disorders, including psoriasis, inflammatory bowel disease, and chronic obstructive pulmonary disease. IL-36 comprises 4 isoforms: the proinflammatory IL-36α, IL-36β, and IL-36γ and the anti-inflammatory IL-36R antagonist. An imbalance between proinflammatory and anti-inflammatory IL-36 isoforms can contribute to the inflammatory fate of cells and tissues. IL-36 cytokines signal through an IL-36R heterodimer mediating their function through canonical signaling cacade, including the NF-B pathway. Prominent for its role in psoriasis, IL-36 has recently been associated with disease mechanisms in atopic dermatitis, hidradenitis suppurativa, neutrophilic dermatoses, autoimmune blistering disease, and Netherton syndrome. The major cutaneous source of IL-36 cytokines is keratinocytes, pointing to its role in the communication between the epidermis, innate (neutrophils, dendritic cells) immune system, and adaptive (T helper [Th]1 cells, Th17) immune system. Thus, cutaneous IL-36 signaling is crucial for the immunopathological outcome of various skin diseases. Consequently, the IL-36/IL-36R axis has recently been recognized as a promising drug target for the treatment of inflammatory disorders beyond psoriasis. This review summarizes the current update on IL-36 cytokines in inflammatory skin diseases.

Dupilumab Alters Both the Bacterial and Fungal Skin Microbiomes of Patients with Atopic Dermatitis

The skin microbiome at lesion sites in patients with atopic dermatitis (AD) is characterized by dysbiosis. Although the administration of dupilumab, an IL-4Rα inhibitor, improves dysbiosis in the bacterial microbiome, information regarding the fungal microbiome remains limited. This study administered dupilumab to 30 patients with moderate-to-severe AD and analyzed changes in both fungal and bacterial skin microbiomes over a 12-week period. Malassezia restricta and M. globosa dominated the fungal microbiome, whereas non-Malassezia yeast species increased in abundance, leading to greater microbial diversity. A qPCR analysis revealed a decrease in Malassezia colonization following administration, with a higher reduction rate observed where the pretreatment degree of colonization was higher. A correlation was found between the group classified by the Eczema Area and Severity Index, the group categorized by the concentration of Thymus and activation-regulated chemokine, and the degree of skin colonization by Malassezia. Furthermore, an analysis of the bacterial microbiome also confirmed a decrease in the degree of skin colonization by the exacerbating factor Staphylococcus aureus and an increase in the microbial diversity of the bacterial microbiome. Our study is the first to show that dupilumab changes the community structure of the bacterial microbiome and affects the fungal microbiome in patients with AD.

Skin as the target for allergy prevention and treatment

The fact that genetic and environmental factors could trigger disruption of the epithelial barrier and subsequently initiate a TH2 inflammatory cascade conversely proposes that protecting the same barrier and promoting adequate interactions with other organs, such as the gut, may be crucial for lowering the risk and preventing atopic diseases, particularly, food allergies. In this review, we provide an overview of structural characteristics that support the epithelial barrier hypothesis in patients with atopic dermatitis, including the most relevant filaggrin gene mutations, the recent discovery of the role of the transient receptor potential vanilloid 1, and the role involvement of the microbiome in healthy and damaged skin. We present experimental and human studies that support the mechanisms of allergen penetration, particularly the dual allergen exposure and the outside-in, inside-out, and outside-inside-outside hypotheses. We discuss classic skin-targeted therapies for food allergy prevention, including moisturizers, steroids, and topical calcineurin inhibitors, along with pioneering trials proposed to change their current use (Prevention of Allergy via Cutaneous Intervention and Stopping Eczema and ALlergy). We provide an overview of the novel therapies that enhance the skin barrier, such as probiotics and prebiotics topical application, read-through drugs, direct and indirect FLG replacement, and interleukin and janus kinases inhibitors. Last, we discuss the newer strategies for preventing and treating food allergies in the form of epicutaneous immunotherapy and the experimental use of single-dose of adeno-associated virus vector gene immunotherapy.

Quantitative Analysis and Molecular Docking Simulation of Flavonols from Eruca sativa Mill. and Their Effect on Skin Barrier Function

Eruca sativa is a commonly used edible plant in Italian cuisine. E. sativa 70% ethanol extract (ES) was fractionated with five organic solvents, including n-hexane (EHex), chloroform (ECHCl3), ethyl acetate (EEA), n-butyl alcohol (EBuOH), and water (EDW). Ethyl acetate fraction (EEA) had the highest antioxidant activity, which was correlated with the total polyphenol and flavonoid content. ES and EEA acted as PPAR-α ligands by PPAR-α competitive binding assay. EEA significantly increased cornified envelope formation as a keratinocyte terminal differentiation marker in HaCaT cells. Further, it significantly reduced nitric oxide and pro-inflammatory cytokines (IL-6 and TNF-α) in lipopolysaccharide-stimulated RAW 264.7 cells. The main flavonol forms detected in high amounts from EEA are mono-and di-glycoside of each aglycone. The main flavonol form of EEA is the mono-glycoside of each aglycone detected, and the most abundant flavonol mono-glycoside is kaempferol 3-glucoside 7.4%, followed by quercetin-3-glucoside 2.3% and isorhamnetin 3-glucoside 1.4%. Flavonol mono-glycosides were shown to be a potent PPAR-α ligand using molecular docking simulation and showed the inhibition of nitric oxide. These results suggest that the flavonol composition of E. sativa is suitable for use in improving skin barrier function and inflammation in skin disorders, such as atopic dermatitis.

Real-World Clinical Experience of Dupilumab in the Treatment of Chronic Palmo-Plantar Eczema in Patients with Moderate-Severe Atopic Dermatitis: 52-Week Follow-Up

Background: Hand-foot eczema (HFE) are special locations of dermatitis, which are often associated with atopic dermatitis (AD) and have a significant negative impact on the quality of life, demanding a clinically relevant improvement. Objectives: To evaluate the effectiveness and safety of dupilumab in the treatment of eczema localized in hands and/or feet in patients with moderate-to-severe AD. Methods: Retrospective multicenter study of adult patients with HFE treated with dupilumab for their AD. Patients with other concomitantly systemic immunosuppressive treatments did not undergo a washout period. The severity of palmar and/or plantar involvement was assessed using the Physician Global Assessment (PGA) scale on a scale of 0 ( = clear) to 5 ( = very severe). Eczema Area and Severity Index (EASI) and NRS-pruritus scales were also evaluated. One hundred percent of patients reached week 16, while 67/84 reached week 52 of follow-up. Results: A total of 84 patients were included 86.69% of patients showed a reduction in PGA-Hand, and 80.34% in PGA-Foot at week 52, EASI improvement was reached by 83.55% of patients at week 16 and 87.35% at week 52. Reduction of pruritus (≥4 points in NRS-pruritus scale) was 73.01% at week 16 and 80.67% at week 52. No differences in response to dupilumab were observed in the different subtypes of palmo-plantar dermatitis. Conclusions: The results obtained in our study suggest that dupilumab may be an effective and safe therapeutic option for the treatment of dermatitis localized in hands and/or feet.

Electrical impedance spectroscopy detects skin barrier dysfunction in childhood atopic dermatitis

BACKGROUND

Skin barrier dysfunction is associated with the development of atopic dermatitis (AD), however methods to assess skin barrier function are limited. We investigated the use of electrical impedance spectroscopy (EIS) to detect skin barrier dysfunction in children with AD of the CARE (Childhood AlleRgy, nutrition, and Environment) cohort.

METHODS

EIS measurements taken at multiple time points from 4 months to 3-year-old children, who developed AD (n = 66) and those who did not (n = 49) were investigated. Using only the EIS measurement and the AD status, we developed a machine learning algorithm that produces a score (EIS/AD score) which reflects the probability that a given measurement is from a child with active AD. We investigated the diagnostic ability of this score and its association with clinical characteristics and age.

RESULTS

Based on the EIS/AD score, the EIS algorithm was able to clearly discriminate between healthy skin and clinically unaffected skin of children with active AD (area under the curve 0.92, 95% CI 0.85-0.99). It was also able to detect a difference between healthy skin and AD skin when the child did not have active AD. There was no clear association between the EIS/AD score and the severity of AD or sensitisation to the tested allergens. The performance of the algorithm was not affected by age.

CONCLUSIONS

This study shows that EIS can detect skin barrier dysfunction and differentiate skin of children with AD from healthy skin and suggests that EIS may have the ability to predict future AD development.

Zinc penetration through the skin barrier in atopic dermatitis and rosacea using reflectance confocal microscopy

Atopic dermatitis (AD) is a chronic, recurrent eczematous disorder with a complex pathophysiology caused by skin barrier abnormalities. Rosacea is a common chronic immune-mediated inflammatory disorder that results in diminished skin barrier function. Reflectance confocal microscopy (RCM) is a non-invasive method for visualizing the dynamic status of epidermal and upper dermal structures. In this study, we compared skin barrier permeability among normal, AD and rosacea groups. To assess skin barrier permeability, zinc was applied to lesional skin and the RCM reflectance intensity of zinc penetration was measured. Reflectance confocal microscopy revealed that the intensity in patients with rosacea and AD was higher than that in the normal group at depths of 8-24 μm in both the face and forearm, which were considered as the stratum corneum (SC) and tight junction (TJ) level (p < 0.0001). When comparing AD and rosacea, the intensity of rosacea was higher than that of AD at a depth of 8 μm in the face (p < 0.0001). The intensity of AD was higher than that of rosacea at a depth of 24 μm (p = 0.009). This suggests that skin barrier permeability is increased in the upper epidermis of patients with AD and rosacea. On the face, patients with rosacea had more SC weakness than did those with AD, whereas patients with AD had more TJ weakness than those with rosacea.

Atopic March or Atopic Multimorbidity-Overview of Current Research

The atopic march encompasses a sequence of allergic conditions, including atopic dermatitis, food allergy, allergic rhinitis, and asthma, that frequently develop in a sequential pattern within the same individual. It was introduced as a conceptual framework aimed at elucidating the developmental trajectory of allergic conditions during childhood. Following the introduction of this concept, it was initially believed that the atopic march represented the sole and definitive trajectory of the development of allergic diseases. However, this perspective evolved with the emergence of new longitudinal studies, which revealed that the evolution of allergic diseases is far more intricate. It involves numerous immunological pathological mechanisms and may not align entirely with the traditional concept of the atopic march. The objective of our review is to portray the atopic march alongside other patterns in the development of childhood allergic diseases, with a specific emphasis on the potential for a personalized approach to the prevention, diagnosis, and treatment of atopic conditions.

Frequency of newborn bathing in the first 9 weeks of life and related factors: An observational study in a community-based sample from Meta-LARC

PURPOSE

Environmental factors such as bathing may play a role in atopic dermatitis (AD) development. This analysis utilized data from the Community Assessment of Skin Care, Allergies, and Eczema (CASCADE) Trial (NCT03409367), a randomized controlled trial of emollient therapy for AD prevention in the general population, to estimate bathing frequency and associated factors within the first 9 weeks of life.

METHODS

Data were collected from 909 parent/newborn dyads recruited from 25 pediatric and family medicine clinics from the Meta-network Learning and Research Center (Meta-LARC) practice-based research network (PBRN) consortium in Oregon, North Carolina, Colorado, and Wisconsin for the CASCADE trial. Ordinal logistic regression was used to conduct a cross-sectional analysis of the association between bathing frequency (measured in baths per week) and demographic, medical, and lifestyle information about the infant, their family, and their household. Variables were selected using a backwards-stepwise method and estimates from the reduced model are reported in the text.

RESULTS

Moisturizer use (OR = 2.03, 95% CI: 1.54-2.68), Hispanic or Latino ethnicity (OR = 1.97, 95% CI: 1.42-2.72), a parental education level lower than a 4-year college degree (OR = 2.48, 95% CI: 1.70-3.62), living in North Carolina or Wisconsin (compared to Oregon; OR = 2.12 and 1.47, 95% CI: 1.53-2.93 and 1.04-2.08, respectively), and increasing child age (in days; OR = 1.02, 95% CI: 1.01-1.02) were significantly associated with more frequent bathing, while pet ownership (OR = 0.67, 95% CI: 0.52-0.87) was significantly associated with less frequent bathing.

CONCLUSIONS

We found significant ethnic, geographic, and socioeconomic variation in bathing frequency before 9 weeks of age that may be of relevance to AD prevention studies.

Excessive Production of Hydrogen Peroxide in Mitochondria Contributes to Atopic Dermatitis

Atopic dermatitis (AD) is a complex disease characterized by chronic recurring eczema and pruritus. In addition, patients with AD display increased cutaneous and systemic levels of oxidative damage markers, whose source remains elusive. In this study, we investigated oxidative and mitochondrial stress in AD epidermis. The levels of superoxide dismutase 2 and hydrogen peroxide are augmented in the mitochondria of flaky tail (ft/ft) mouse keratinocytes, which is associated with the inhibition of the glutathione system and catalase. Furthermore, reduced levels of glutathione peroxidase 4 are associated with accumulation of malondialdehyde, 4-hydroxy-2-nonenal, and oxidized phosphatidylcholines in ft/ft epidermis. Cytochrome c is markedly increased in ft/ft epidermis, hence showing mitochondrial stress. Topical application of MitoQ, which is a mitochondrial-targeting antioxidant, to ft/ft mouse skin reduced damage to macromolecules and inflammation and restored epidermal homeostasis. Absence of alteration in the expression of superoxide dismutase 2, catalase, and glutathione peroxidase 4 and limited lipid peroxidation as well as oxidized phosphatidylcholines in the epidermis of Flg-/- mice suggest that FLG deficiency marginally contributes to oxidative stress in ft/ft epidermis. Increased superoxide dismutase 2, lipid peroxidation, and cytochrome c in the epidermis of patients with AD, associated with reduced antioxidant response in primary AD keratinocytes, corroborate mitochondrial dysfunction and lack of cellular adjustment to oxidative stress in AD epidermis.

Protective effect of Lycium barbarum leaf extracts on atopic dermatitis: in vitro and in vivo studies

BACKGROUND/OBJECTIVES

Atopic dermatitis (AD) is a chronic disease with an increasing incidence globally; therefore, there is a growing demand for natural compounds effective in treating dermatitis. In this study, the protective effects of Lycium barbarum leaves with and without chlorophyll (LLE and LLE[Ch-]) on AD were investigated in animal models of AD and HaCaT cells. Further, we investigated whether LLE and LLE(Ch-) show any differences in physiological activity.

MATERIALS/METHODS

AD was induced by 2,4-dinitrochlorobenzene (DNCB) for three weeks, while NC/Nga mice were fed LLE or LLE(Ch-) extracts for 7 weeks. Serum immunoglobulin E (IgE) and cytokine (tumor necrosis factor [TNF]-α, interleukin [IL]-6, and IL-4) concentrations and the degree of DNA fragmentation in lymphocytes were examined. A histopathological examination (haematoxylin & eosin staining and blue spots of toluidine) of the dorsal skin of mice was performed. To elucidate the mechanism of action, the expression of the thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) were measured in HaCaT cells.

RESULTS

Serum IgE and cytokines (TNF-α and IL-6) levels as well as DNA fragmentation of lymphocytes were significantly decreased in AD-induced mice treated with LLE or LLE(Ch-) compared to those of the control group. The epidermal thickness of the dorsal skin and mast cell infiltration in the LLE group significantly reduced compared to that in the control group. The LLE extracts showed no cytotoxicity up to 1,000 µg/mL in HaCaT cells. LLE or LLE(Ch-)-treated group showed a reduction of TARC and MDC in TNF-α-and IFN-γ-stimulated HaCaT cells.

CONCLUSIONS

These results suggest that LLE potentially improves inflammation by reducing the expression of chemokines that inhibit T helper 2 cell migration. LLE(Ch-) showed similar effects to LLE on blood levels of IgE, TNF-α and IL-6 and protein expression in HaCat cells, but the ultimate effect of skin improvement was not statistically significant. Therefore, both LLE and LLE(Ch-) can be used as functional materials to alleviate AD, but LLE(Ch-) appears to require more research to improve inflammation.

Evaluation of the Impact of Serum Vitamin D Levels on the Scoring Atopic Dermatitis Index in Pediatric Atopic Dermatitis

Atopic dermatitis (AD) is a chronic and recurrent inflammatory skin condition characterized by itching, eczematous plaques, and dry skin. Despite ongoing research, its exact cause remains elusive. In this study, we aimed to explore the factors that influence the severity of AD in children and assess the relationship between serum vitamin D levels and the disease's severity. We enrolled 96 AD patients in our investigation, evaluated their clinical condition using the Scoring Atopic Dermatitis (SCORAD) index, and compared them to a group of 90 healthy controls. Our analysis revealed that serum vitamin D levels and eosinophil counts significantly impacted the SCORAD index (p < 0.001). According to standardized regression coefficients, for each incremental unit in serum vitamin D levels, the SCORAD index exhibited a decrease of 0.449 units. Similarly, a one-unit increase in eosinophil count resulted in a 0.009 unit increase in the SCORAD index. It is worth noting that the influence of serum vitamin D levels on disease severity surpasses that of eosinophil counts and atopic conditions. In our patient cohort, we uncovered a negative correlation (r = -0.419, p < 0.001) between serum vitamin D levels and the SCORAD index. Our findings suggest that low serum vitamin D levels may have a more substantial impact on AD severity than atopic conditions and eosinophilia. Furthermore, we observed a negative association between the severity of AD and serum 25(OH)D3 levels.

IL-32 as a potential biomarker and therapeutic target in skin inflammation

IL-32 is a recently described cytokine that performs a variety of functions under inflammatory conditions. Serum IL-32 has been shown to be elevated in several diseases, including type 2 diabetes, cancer, systemic lupus erythematosus, HIV infection, and atopic diseases including atopic dermatitis. There are nine different isoforms of IL-32, with IL-32γ being the most biologically active one. The following review summarizes the different roles of the various IL-32 isoforms in the context of skin inflammation, with a focus on atopic dermatitis.

Emerging Trends and Focus in Human Skin Microbiome Over the Last Decade: A Bibliometric Analysis and Literature Review

Background

Human skin microbiome is the first barrier against exogenous attack and is associated with various skin disease pathogenesis and progression. Advancements in high-throughput sequencing technologies have paved the way for a deeper understanding of this field. Based on the bibliometric analysis, this investigation aimed to identify the hotspots and future research trends associated with human skin microbiomes studied over the past decade.

Methods

The published research on skin microbiome from January 2013 to January 2023 was retrieved from the Web of Science Core Collection. Data cleaning processes to ensure robust data and the bibliometrix packages R, CiteSpace, VOSviewer, Origin, and Scimago Graphica for bibliometric and visual analyses were utilized.

Results

A total of 1629 published documents were analyzed. The overall publication trend steadily increased, with relatively fast growth in 2017 and 2020. The United States of America has the highest number of publications and citations and shows close collaborations with China and Germany. The University of California, San Diego, indicated a higher number of publications than other institutions and the fastest growth rate. The top three most publishing journals on this topic are Microorganisms, Frontiers in Microbiology, and Experimental dermatology. Gallo RL is the most influential author with the highest h- and g-index and most publications in skin microecology, followed by Grice EA and Kong HH. The top 10 most frequently used keywords in recent years included skin microbiome, microbiome, staphylococcus aureus, diversity, atopic dermatitis, skin, bacteria, infections, gut microbiota, and disease.

Conclusion

The skin microbiome is an area of research that requires continuous analysis, and even with much-achieved progress, future research will further be aided as technology develops.

Environmental Air Pollutants Affecting Skin Functions with Systemic Implications

The increase in air pollution worldwide represents an environmental risk factor that has global implications for the health of humans worldwide. The skin of billions of people is exposed to a mixture of harmful air pollutants, which can affect its physiology and are responsible for cutaneous damage. Some polycyclic aromatic hydrocarbons are photoreactive and could be activated by ultraviolet radiation (UVR). Therefore, such UVR exposure would enhance their deleterious effects on the skin. Air pollution also affects vitamin D synthesis by reducing UVB radiation, which is essential for the production of vitamin D3, tachysterol, and lumisterol derivatives. Ambient air pollutants, photopollution, blue-light pollution, and cigarette smoke compromise cutaneous structural integrity, can interact with human skin microbiota, and trigger or exacerbate a range of skin diseases through various mechanisms. Generally, air pollution elicits an oxidative stress response on the skin that can activate the inflammatory responses. The aryl hydrocarbon receptor (AhR) can act as a sensor for small molecules such as air pollutants and plays a crucial role in responses to (photo)pollution. On the other hand, targeting AhR/Nrf2 is emerging as a novel treatment option for air pollutants that induce or exacerbate inflammatory skin diseases. Therefore, AhR with downstream regulatory pathways would represent a crucial signaling system regulating the skin phenotype in a Yin and Yang fashion defined by the chemical nature of the activating factor and the cellular and tissue context.

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

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

In silico analysis of the profilaggrin sequence indicates alterations in the stability, degradation route, and intracellular protein fate in filaggrin null mutation carriers

Background: Loss of function mutation in FLG is the major genetic risk factor for atopic dermatitis (AD) and other allergic manifestations. Presently, little is known about the cellular turnover and stability of profilaggrin, the protein encoded by FLG. Since ubiquitination directly regulates the cellular fate of numerous proteins, their degradation and trafficking, this process could influence the concentration of filaggrin in the skin. Objective: To determine the elements mediating the interaction of profilaggrin with the ubiquitin-proteasome system (i.e., degron motifs and ubiquitination sites), the features responsible for its stability, and the effect of nonsense and frameshift mutations on profilaggrin turnover. Methods: The effect of inhibition of proteasome and deubiquitinases on the level and modifications of profilaggrin and processed products was assessed by immunoblotting. Wild-type profilaggrin sequence and its mutated variants were analysed in silico using the DEGRONOPEDIA and Clustal Omega tool. Results: Inhibition of proteasome and deubiquitinases stabilizes profilaggrin and its high molecular weight of presumably ubiquitinated derivatives. In silico analysis of the sequence determined that profilaggrin contains 18 known degron motifs as well as multiple canonical and non-canonical ubiquitination-prone residues. FLG mutations generate products with increased stability scores, altered usage of the ubiquitination marks, and the frequent appearance of novel degrons, including those promoting C-terminus-mediated degradation routes. Conclusion: The proteasome is involved in the turnover of profilaggrin, which contains multiple degrons and ubiquitination-prone residues. FLG mutations alter those key elements, affecting the degradation routes and the mutated products' stability.

Association of soap use when bathing 18-month-old infants with the prevalence of allergic diseases at age 3 years: The Japan Environment and Children's Study

BACKGROUND

Atopic march is defined as the progression from atopic dermatitis (AD) during early life to other allergic diseases in later childhood. In a nationwide birth cohort study, the Japan Environment and Children's Study, we investigated the association of bathing habits, which are known to affect skin conditions, for infants with their later development of allergic diseases.

METHODS

Pregnant women who lived in 15 designated regional centers throughout Japan were recruited. We obtained information on bathing habits for their 18-month-old infants and the prevalence of allergic diseases when they were aged 3 years.

RESULTS

Data for 74,349 children were analyzed. Most 18-month-old infants were bathed or showered almost every day. When they were divided into four groups according to the frequency of soap use during bathing (every time, most of the time, sometimes, and seldom), the risk of AD later at age 3 was shown to increase in association with a decreasing frequency of soap use [most of the time: adjusted odds ratio (aOR) 1.18, 95% confidence interval (CI) 1.05-1.34; sometimes: aOR 1.72, 95% CI 1.46-2.03; seldom: aOR 1.99, 95% CI 1.58-2.50], compared with soap use every time during bathing at 18 months of age. Similar results were obtained for food allergy but not for bronchial asthma.

CONCLUSIONS

Frequent soap use when bathing 18-month-old infants was associated with a decreased risk of them developing allergic diseases at age 3. Further well-designed clinical studies are warranted to determine an effective bathing regimen for preventing the development of allergic diseases.

Why traditional herbal medicine promotes wound healing: Research from immune response, wound microbiome to controlled delivery

Impaired wound healing in chronic wounds has been a significant challenge for clinicians and researchers for decades. Traditional herbal medicine (THM) has a long history of promoting wound healing, making them culturally accepted and trusted by a great number of people in the world. However, for a long time, the understanding of herbal medicine has been limited and incomplete, particularly in the allopathic medicine-dominated research system. The therapeutic effects of individual components isolated from THM are found less pronounced compared to synthetic chemical medicine, and the clinical efficacy is always inferior to herbs. In the present article, we review and discuss underlying mechanisms of the skin microbiome involved in the wound healing process; THM in regulating immune responses and commensal microbiome. We additionally propose few pioneer ideas and studies in the development of therapeutic strategies for controlled delivery of herbal medicine. This review aims to promote wound care with a focus on wound microbiome, immune response, and topical drug delivery systems. Finally, future development trends, challenges, and research directions are discussed.

Stratum corneum lipid and cytokine biomarkers at age 2 months predict the future onset of atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) commonly occurs in children and can progress into severe phenotypes or atopic march, causing significant impairment in quality of life. It is important to find early biomarkers of future onset of AD before any clinical manifestations.

OBJECTIVE

We sought to find early predictors of future onset of AD in skin stratum corneum (SC).

METHODS

Skin tape strips were collected from the forearm of newborns (n = 111) with and without family history of atopic diseases at the age of 2 months before any signs of clinical AD. Children were clinically monitored until they reached age 2 years to ensure the presence or absence of AD. Skin tape strips were subjected to lipidomic analyses by the liquid chromatography electrospray ionization tandem mass spectrometry and cytokine determination by Meso Scale Discovery U-Plex assay.

RESULTS

Overall, 22 of 74 (29.7%) and 5 of 37 (13.5%) infants developed AD in the risk group and the control group, respectively. In the SC of future AD children, protein-bound ceramides were decreased (P < .001), whereas unsaturated sphingomyelin species (P < .0001) and "short-chain" nonhydroxy fatty acid sphingosine and alpha-hydroxy fatty acid sphingosine ceramides were elevated (P < .01 and .05, respectively) as compared with healthy children. Thymic stromal lymphopoietin and IL-13 levels were increased in the SC of future AD subjects (by 74.5% and 78.3%, P = .0022 and P < .0001, respectively). Multivariable logistic regression analysis revealed strong AD predicting power of the combination of family history, type 2 cytokines, and dysregulated lipids, with an odds ratio reaching 54.0 (95% CI, 9.2-317.5).

CONCLUSIONS

Noninvasive skin tape strip analysis at age 2 months can identify asymptomatic children at risk of future AD development with a high probability.

Abnormalities of Sphingolipids Metabolic Pathways in the Pathogenesis of Psoriasis

Psoriasis is immune-mediated skin disorder affecting thousands of people. Sphingolipids (SLs) are bioactive molecules present in the epidermis, involved in the following cellular processes: proliferation, differentiation, and apoptosis of keratinocytes. Alterations in SLs synthesis have been observed in psoriatic skin. To investigate if the imbalance in lipid skin metabolism could be related to psoriasis, we analyzed the gene expression in non-lesioned and lesioned skin of patients with psoriasis available in two datasets (GSE161683 and GSE136757) obtained from National Center for Biotechnology Information (NCBI). The differentially expressed genes (DEGs) were searched for using NCBI analysis, and Gene Ontology (GO) biological process analyses were performed using the Database of Annotation, Visualization, and Integrated Discovery (DAVID) platform. Venn diagrams were done with InteractiVenn tool and heatmaps were constructed using Morpheus software. We observed that the gene expression of cytoplasmic phospholipase A₂ (PLA2G4D), glycerophosphodiester phosphodiesterase domain containing 3 (GDP3), arachidonate 12-lipoxygenase R type (ALOX12B), phospholipase B-like 1 (PLBD1), sphingomyelin phosphodiesterase 3 (SMPD3), ganglioside GM2 activator (GM2A), and serine palmitoyltransferase long chain subunit 2 (SPTLC2) was up-regulated in lesioned skin psoriasis when compared with the non-lesioned skin. These genes are related to lipid metabolism and more specifically to sphingolipids. So, in the present study, the role of sphingolipids in psoriasis pathogenesis is summarized. These genes could be used as prognostic biomarkers of psoriasis and could be targets for the treatment of patients who suffer from the disease.

Clinically meaningful improvements in cutaneous lesions and quality of life measures in patients with atopic dermatitis with greater pruritus reductions after treatment with 60 mg nemolizumab subcutaneously every 4 weeks: Subgroup analysis from a phase 3, randomized, controlled trial

BACKGROUND

Data from the Japanese phase 3 Nemolizumab-JP01 study (JapicCTI-173740) found that nemolizumab in combination with topical treatments reduced pruritus associated with atopic dermatitis inadequately controlled with current therapies.

METHODS

This post-hoc analysis examined associations between improvements in pruritus (visual analog scale [VAS]) and eczema (Eczema Area and Severity Index [EASI]), and achievement of other clinically relevant endpoints including the Insomnia Severity Index (ISI), Dermatology Life Quality Index (DLQI), and Patient-Oriented Eczema Measure (POEM).

RESULTS

Pruritus VAS responders (≥50% improvement from baseline to week 16) showed greater improvements from baseline in these additional endpoints as early as week 1, compared with non-responders. Responders also had EASI improvement, and more than 80% achieved an ISI score ≤7, or had improvement in the DLQI or POEM. The percent change from baseline in VAS and EASI scores at week 16 was in favor of nemolizumab in all subgroups based on baseline characteristics. No specific factor affecting treatment response to nemolizumab was identified.

CONCLUSIONS

In this post-hoc analysis, nemolizumab-treated patients who had greater pruritus reductions also showed improvements in other eczema symptoms; pruritus alleviation appeared to be responsible for the improvements in eczema, sleep and daily life.

Blockage of the IL-31 Pathway as a Potential Target Therapy for Atopic Dermatitis

Atopic dermatitis (AD), a pruritic, inflammatory chronic disease with multifactorial pathogenesis, has been a therapeutic challenge. Novel target treatments aim to reduce not only the immunologic dysfunction and microbiome dysbiosis but also the recovery of the damaged skin barrier. The current review focuses on the interleukin 31 (IL-31) pathway and AD and offers an overview of the current clinical studies with monoclonal antibodies blocking this cascade. Pruritus, the key symptom of AD, has substantial participation of the IL-31 complex and activation of relevant signaling pathways. Epidermal keratinocytes, inflammatory cells, and cutaneous peripheral nerves express the interleukin-31 receptor α-chain (IL-31RA), upregulated by Staphylococcus aureus toxins or Th2 cytokines involved in AD. Nemolizumab is a humanized monoclonal antibody that antagonizes IL-31RA, inhibiting the IL-31 cascade and therefore contributing to reducing the pruritus and inflammation and recovering the damaged skin barrier in AD patients. Phases 2 and 3 clinical trials with nemolizumab in AD show a suitable safety profile, with a fast, efficient, and sustained reduction of pruritus and severity scores, especially when associated with topical treatment. Deciphering the full interplay of the IL-31 pathway and AD may expand the potential of nemolizumab as a targeted therapy for AD and other pruritic conditions.

Gene-environment interactions and their impact on human health

The molecular processes underlying human health and disease are highly complex. Often, genetic and environmental factors contribute to a given disease or phenotype in a non-additive manner, yielding a gene-environment (G × E) interaction. In this work, we broadly review current knowledge on the impact of gene-environment interactions on human health. We first explain the independent impact of genetic variation and the environment. We next detail well-established G × E interactions that impact human health involving environmental toxicants, pollution, viruses, and sex chromosome composition. We conclude with possibilities and challenges for studying G × E interactions.

Design and Characterization of Lipid-Surfactant-Based Systems for Enhancing Topical Anti-Inflammatory Activity of Ursolic Acid

Skin inflammation is a symptom of many skin diseases, such as eczema, psoriasis, and dermatitis, which cause rashes, redness, heat, or blistering. The use of natural products with anti-inflammatory properties has gained importance in treating these symptoms. Ursolic acid (UA), a promising natural compound that is used to treat skin diseases, exhibits low aqueous solubility, resulting in poor absorption and low bioavailability. Designing topical formulations focuses on providing adequate delivery via application to the skin surface. The aim of this study was to formulate and characterize lipid-surfactant-based systems for the delivery of UA. Microemulsions and liquid crystalline systems (LCs) were characterized by polarized light microscopy (PLM), rheology techniques, and textural and bioadhesive assays. PLM supported the self-assembly of these systems and elucidated their formation. Rheologic examination revealed pseudoplastic and thixotropic behavior appropriate, and assays confirmed the ability of these formulations to adhere to the skin. In vivo studies were performed, and inflammation induced by croton oil was assessed for response to microemulsions and LCs. UA anti-inflammatory activities of ~60% and 50% were demonstrated by two microemulsions and 40% and 35% by two LCs, respectively. These data support the continued development of colloidal systems to deliver UA to ameliorate skin inflammation.

The Role of TSLP in Atopic Dermatitis: From Pathogenetic Molecule to Therapeutical Target

Atopic dermatitis (AD) is a kind of chronic skin disease with inflammatory infiltration, characterized by skin barrier dysfunction, immune response dysregulation, and skin dysbiosis. Thymic stromal lymphopoietin (TSLP) acts as a regulator of immune response, positively associated with AD deterioration. Mainly secreted by keratinocytes, TSLP interacts with multiple immune cells (including dendritic cells, T cells, and mast cells), following induction of Th2-oriented immune response during the pathogenesis of AD. This article primarily focuses on the TSLP biological function, the relationship between TSLP and different cell populations, and the AD treatments targeting TSLP.

Electrospun fibers as carriers for topical drug delivery and release in skin bandages and patches for atopic dermatitis treatment

The skin is a complex layer system and the most important barrier between the environment and the organism. In this review, we describe some widespread skin problems, with a focus on eczema, which are affecting more and more people all over the world. Most of treatment methods for atopic dermatitis (AD) are focused on increasing skin moisture and protecting from bacterial infection and external irritation. Topical and transdermal treatments have specific requirements for drug delivery. Breathability, flexibility, good mechanical properties, biocompatibility, and efficacy are important for the patches used for skin. Up to today, electrospun fibers are mostly used for wound dressing. Their properties, however, meet the requirements for skin patches for the treatment of AD. Active agents can be incorporated into fibers by blending, coaxial or side-by-side electrospinning, and also by physical absorption post-processing. Drug release from the electrospun membranes is affected by drug and polymer properties and the technique used to combine them into the patch. We describe in detail the in vitro release mechanisms, parameters affecting the drug transport, and their kinetics, including theoretical approaches. In addition, we present the current research on skin patch design. This review summarizes the current extensive know-how on electrospun fibers as skin drug delivery systems, while underlining the advantages in their prospective use as patches for atopic dermatitis. This article is categorized under: Implantable Materials and Surgical Technologies > Nanomaterials and Implants Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Anti-inflammatory and immunomodulatory effects of polysaccharide extracted from Wuguchong (maggot) on 2,4-dinitrochlorobenzene-induced atopic dermatitis in mice

Atopic dermatitis (AD) is an inflammatory, heterogeneous, chronic skin disorder characterized by recurrent eczematous lesions and intense pruritus, and the pathophysiology mechanism of AD is known for immune dysregulation and inflammatory responses. Wuguchong (maggot) has been widely used in the wound field and found with pharmacological properties of the anti-inflammatory and immunomodulatory function. Recently, some polysaccharides were proven to have beneficial effects on AD skin lesions in mice and humans. However, the effect of the polysaccharide extracted from Wuguchong (PEW) on AD remains to be investigated. In the present study, we examined the anti-inflammatory and immunomodulatory effects of PEW on AD and explored the potential mechanisms. Balb/c mice were orally administrated with PEW to evaluate the therapeutic effect of PEW on 2,4-dinitrochlorobenzene (DNCB)-induced AD. Oral PEW administration significantly ameliorated the lesions and symptoms in AD mice, such as the ear thickness and ear swelling degree, epidermal and dermal thickness, and the infiltration of mast cells. In addition, PEW treatment decreased the levels of serum IgE and histamine, the frequencies of Th1 and Th17 cells, as well as the mRNA expression levels of Th1 and Th17 cytokines and nuclear transcript factors (IFN-γ, T-bet, IL-17A, and ROR-rt). Furthermore, the activation of the NF-κB pathway and the phosphorylation of MAPKs (p38, ERK, and JNK) were significantly suppressed by PEW treatment. Taken together, our study suggests that PEW exerts anti-inflammatory and immunomodulatory effects through inhibition of Th1 and Th17 responses and downregulation of NF-κB and MAPK pathways, PEW would be developed as a promising immune therapy for AD.

The Role of a Novel Generation of Emollients, 'Emollients Plus', in Atopic Dermatitis

Emollients are the mainstay maintenance treatment for atopic dermatitis (AD). A novel generation of emollients, 'emollients plus', containing active, non-medicated substances, has softened the distinction between emollients and topical drugs. A literature search for selected key words was performed using PubMed. Additional papers were identified based on author expertise. Whilst the inclusion of five components of an ideal emollient has been proposed, no such consensus exists for emollients plus and they can vary markedly in their composition and modes of action for AD treatment. This could have a profound effect on their clinical efficacy. The efficacy of emollients plus in restoring and maintaining skin barrier function has been demonstrated on multiple levels, with evidence reported for their effects on the physical and biochemical, microbial, immunological, and neurosensory barriers. When selecting an appropriate AD treatment approach, the safety profiles of the available topical therapies must be carefully considered. There are several proposed treatment approaches for AD, including preventive, proactive, intermittent, and synergistic approaches. Emollients plus may be effective not only as maintenance therapy for AD, but also when used synergistically with anti-inflammatory pharmacological therapies.

Metal Allergy: State-of-the-Art Mechanisms, Biomarkers, Hypersensitivity to Implants

Metal allergy is mainly an environmental disorder which can cause allergic contact dermatitis. Environmental metal exposures include jewelry, everyday metal items, mobile phones, leather, metal-rich food and implants, including stents or anchors. While consumer exposure is liable for the majority of metal hypersensitivity cases, the significance of occupational exposure to metals remains relevant. Although the most common metal allergens are nickel, chromium, and cobalt; however, lately, gold, palladium, titanium, and some others have also attracted attention. This review highlights advances in metal allergy mechanisms, biomarkers for potential patients' stratification as well as biological treatments. The most recent evidence of human exposure to metal for risk assessment is discussed, as well as the relationship between the occurrence of metal hypersensitivity and implanted devices, including non-characteristic symptoms. The latest data on the diagnosis of metal hypersensitivity are also reported.

Granzyme B: A novel therapeutic target for treatment of atopic dermatitis

Granzyme B is a serine protease that can play multiple roles in intracellular and extracellular perforin-dependent or non-perforin-dependent mechanisms. Granzyme B has been found to be an important factor involved in the pathogenesis of atopic dermatitis and is increased in both skin lesions and peripheral blood of atopic dermatitis patients. In this article, we review the correlation between granzyme B and atopic dermatitis to provide a novel therapeutic targeting option for clinical treatment of the latter.

Novel filagrinol-containing emollient

ABSTRACT:In the last decade, there has been a significant increase in interest in the study of the role of epidermal barrier structural integrity in order to determine the prospects for its pathogenetic correction. It is now known that patients with filaggrin gene mutations have increased risk of developing atopic dermatitis, xerosis, ichthyosis, eczema. Filaggrin participates in the formation of a full-fledged stratum corneum, provides formation of a natural moisturizing factor, stabilizing the water balance of the stratum corneum. In Russia, the innovative filaggrin-containing "Admera" has been registered, which opens up prospects in the management impaired skin barrier function diseases. Aims:efficacy and safety of "Admera" emollient in patients with primary and secondary xerosis. Methods:A single-center prospective interventional study December 2021 - March 2022 at the Department of Skin and Venereal Diseases of the Sechenov University. The study included 32 patients (22 - main group, 10 - control group) aged 18 to 60 years (29 9.78), 14 men and 18 women diagnosed with skin xerosis. Patients applied moisturizers 3 times a day for 21 days. Performance was evaluated using vIGA-AD, POEM, EASI, 5D Elman scale, SKINDEX-29, HADS, on Capricorn AI, ANTERA 3D machines. Results:A steady regression of clinical symptoms of xerosis was noted during the study by the dynamics of the study scales. The mean EASI score decreased by 67% from 25.25 18.78 - screening to 7.8 4.41 - control visit (p 0.001). Assessment of POEM index dynamics showed a significant decrease in total score from 18.65 to 6.6 (p 0.001). There was good tolerability of the drug and absence of adverse events. Conclusion:The filagrinol-containing emollient "Admera" demonstrated high efficacy and safety in all patients. This emollient can be recommended as a basic care product for treatment and prevention of primary, secondary xerosis, relapses of atopic dermatitis.

A population of dermal Langerin+ dendritic cells promote the inflammation in mouse model of atopic dermatitis

Cutaneous dendritic cells (DCs) have been implicated in the pathogenesis of atopic dermatitis (AD). However, the specific role of different subsets of DCs has not been well defined. This study aimed to investigate the contributions of Langerhans cells (LCs), resident dermal Langerin⁺ DCs (r-Langerin⁺ dDCs), and newly infiltrated inflammatory dermal Langerin⁺ DCs (i-Langerin⁺ dDCs) in an AD mouse model induced by the topical application of MC903. The result showed that depletion of i-Langerin⁺ dDCs in DTR mice after multiple diphtheria toxin (DT) injection significantly reduced thymic stromal lymphopoietin (TSLP) production in lesions and skin inflammation alleviation. However, depletion of LCs or r-Langerin⁺ dDCs didn’t resulted in significant changes in skin inflammation of DTA or single DT injection-treated DTR mice compared with the wild-type (WT) mice. DT-treated DTR-WT chimeric mice with the depletion of bone marrow (BM)-derived i-Langerin⁺ dDCs resulted in markedly decreased skin inflammation than controls, while PBS-treated chimeric mice (DTR-WT) with only the depletion of r-Langerin⁺ dDCs showed inflammation comparable to that in WT mice. Furthermore, TSLP contributed to the upregulation of Langerin expression in BM-derived DCs and promoted the maturation of Langerin⁺ DCs. In summary, the present study demonstrated that the newly infiltrated inflammatory dermal Langerin⁺ DCs were essential for AD development and local TSLP production, and TSLP further promoted the production of BM-derived i-Langerin⁺ dDCs, which might maintain AD inflammation.