Update on the Pathogenesis and Therapy of Atopic Dermatitis

Discovery and Optimization of Potent and Highly Selective PARP14 Inhibitors for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic, recurrent, and inflammatory skin condition that remains challenging to treat effectively and safely with current therapies. Recent studies by multiple independent research groups have demonstrated that poly(ADP-ribose) polymerase 14 (PARP14) has been implicated in the progression of inflammatory diseases through its regulation of the Th2 and Th17 signaling pathways, leading to the identification of PARP14 as a promising therapeutic target. Herein, we report the discovery of a novel PARP14 inhibitor Q22 with exceptional inhibitory activity against PARP14 (IC50 = 5.52 nM), high selectivity toward PARP14, favorable pharmacokinetic properties, and a robust in vivo safety profile. Notably, compared to positive control RBN-3143, Q22 showed significant therapeutic efficacy in a dinitrochlorobenzene (DNCB)-induced AD mouse model by markedly reducing the expression of key AD-associated inflammatory cytokines, including IL-4, IL-13, and IL-17A. These findings suggest that Q22 holds considerable promise as a PARP14 inhibitor for AD treatment.

Separable Microneedle Patch Integrated with the Dictamnine-Loaded Copper MOF Nanozyme for Atopic Dermatitis Treatment

Atopic dermatitis (AD) is a chronic inflammatory skin disorder marked by skin thickening, severe pruritus, lesions, and emotional disturbances, including anxiety and depression-like behavior. Current treatments primarily rely on localized therapies, which can lead to adverse effects such as hyperglycemia and Cushing's syndrome with repeated use. To address these issues, we developed a hyaluronic acid-based separable microneedle patch (Dic@pCu-HA MN), integrating polydopamine-coordinated copper-based metal-organic frameworks (pCu-MOFs) and the anti-inflammatory agent dictamnine (Dic), for synergistic management of AD and its neuropsychiatric comorbidities. pCu-MOFs exhibited dual functionality as nanocargo for hydrophobic Dic (encapsulation efficiency: 84.62 ± 2.14%) and multienzyme mimics that efficiently scavenge reactive oxygen species (ROS) (superoxide radical scavenging: 63.85 ± 0.34%). In vitro release studies demonstrated ROS-responsive Dic release of 86.80 ± 4.83% over 48 h under AD pathology-mimicking conditions. In a 1-Chloro-2,4-dinitrochlorobenzene (DNCB)-induced AD mouse model, the Dic@pCu-HA MN significantly reduced oxidative stress (8-OHdG: 85.1 ± 7.0% decrease), suppressed pro-inflammatory cytokines (IL-4: 70.0 ± 7.8% decrease vs control), and restored skin barrier integrity. By modulating the HPA axis, the system attenuated neuroinflammation and alleviated itching (scratching frequency: 40.1 ± 41.3% reduction) and depression-like behavior (time in the bright box: 96.6 ± 156.2% increase). This combined therapeutic approach not only offers a comprehensive strategy for AD management but also provides potential benefits for addressing inflammatory skin disorders and their neuropsychiatric sequelae.

Atopic dermatitis relapse after treatment discontinuation and predictive factors for relapse: JAK1 inhibitors versus dupilumab

BACKGROUND AND OBJECTIVES

In the clinical management of atopic dermatitis (AD), treatment discontinuations and subsequent disease relapse are common. Understanding relapse patterns following treatment discontinuation in AD patients is therefore essential. This study aims to investigate the time to relapse and identify predictive factors in patients with moderate-to-severe AD who responded to treatment with selective Janus kinase 1 (JAK1) inhibitors (upadacitinib or abrocitinib) or dupilumab.

PATIENTS AND METHODS

This single-center, retrospective cohort analysis reviewed the data for patients aged ≥ 12 years with moderate-to-severe AD who responded to either JAK1 inhibitors or dupilumab within 16 weeks. The primary outcome measures included the median time to skin lesion relapse after treatment discontinuation. Additionally, predictors for relapse were explored.

RESULTS

Within 72 weeks after discontinuation, the median time to skin lesion relapse after discontinuation for JAK1 inhibitor and dupilumab responders was 60 and 457 days, respectively. Overall, 52.9% and 34.6% of patients who used JAK1 inhibitors and dupilumab reported AD skin lesion relapse (average hazard ratio = 2.58, 95% confidence interval: 1.25-5.33, p = 0.01). No other factors influencing AD relapse were identified.

CONCLUSIONS

After treatment discontinuation, Dupilumab showed relatively longer efficacy than JAK1 inhibitors, resulting in a lower risk of relapse.

Liangxue Qushi Zhiyang Decoction Inhibits Atopic Dermatitis in Mice via FcγR-Mediated Phagocytosis

Background: Liangxue Qushi Zhiyang Decoction (LQZ) is a traditional formula known for its efficacy in treating Atopic Dermatitis (AD). However, the specific mechanisms through which LQZ alleviates AD symptoms remain largely unknown. The objective of this study is to investigate the protective effects of LQZ on AD and to uncover its potential mechanisms of action. Methods: An AD model was established in mice using 2,4-dinitrochlorobenzene (DNCB). Mice were then orally administered LQZ or prednisolone (PDN). Throughout the treatment period, dermatitis scores and scratching frequencies of the mice were regularly monitored. Histopathological analyses were conducted using hematoxylin and eosin (H&E) staining and toluidine blue (TB) staining. Serum levels of inflammatory cytokines were measured using enzyme-linked immunosorbent assay (ELISA). Further, tandem mass tag (TMT) labeling quantitative proteomics was employed to identify differentially expressed proteins (DEPs). Enrichment analysis was conducted to pinpoint potential targets and pathways involved in LQZ's therapeutic action. Finally, validation experiments were performed to further explore the specific pathways and core targets of LQZ in AD treatment.. Results: LQZ treatment notably mitigated the skin barrier damage and inflammatory response induced by DNCB in AD mice, and reduced the serum levels of IgE, IL-4, and IL-1β. Proteomic analysis identified 248 proteins with differential expression, implicating multiple pathways in LQZ' therapeutic action. Among these, the Fc gamma R(FcγR)-mediated phagocytosis pathway emerged as a crucial factor in AD's inflammatory and immune responses. Key proteins associated with this pathway, including Fc-gamma RIII (Fcgr3), V-yes-1 Yamaguchi sarcoma viral related oncogene homolog (Lyn), Tyrosine-protein kinase (Syk), Phosphoinositide phospholipase C-gamma-2 (Plcg2), Neutrophil cytosol factor 1 (Ncf1), Ras-related C3 botulinum toxin substrate 2 (Rac2) and Actin-related protein 2/3 complex subunit 3 (Arpc3), exhibited significantly reduced expression levels following LQZ treatment. Conclusion: LQZ is effective in treating AD by alleviating skin barrier damage and inflammatory reactions. Its anti-AD properties of LQZ may be attributed to the inhibition of the FcγR-mediated phagocytic pathway.

The influence of the gut microbiota on B cells in autoimmune diseases

Mounting evidence shows that gut microbiota communities and the human immune system coexist and influence each other, and there are a number of reports of a correlation between specific changes in gut microbiota and the occurrence of autoimmune diseases. B lymphocytes play a central role in the regulation of both gut microbiota communities and in autoimmune diseases. Here, we summarize evidence of the influence of gut microbiota-B cell pathways on autoimmune diseases and how B cells regulate microorganisms, which provides mechanistic insights with relevance for identification of potential therapeutic targets and related fields.

Identification of atopic dermatitis-associated diseases based on the National health and nutrition examination survey (NHANES) 2013-2018

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease. Massive cohort studies revealed that AD was associated with allergic diseases, inflammatory diseases, autoimmune diseases, cardiovascular diseases, and mental disorders. We comprehensively and systematically analyzed the correlation between AD and diseases to identify AD-associated diseases (ADADs). We involved 17,924 individuals from the National Health and Nutrition Examination Survey (NHANES) (2013-2018) dataset, and analyzed the correlation between AD and 422 diseases classified by International Classification of Diseases-10 (ICD-10) using four logistic regression models. We found that AD is significantly associated with 33 diseases: (1) allergic diseases, including urticaria, allergic rhinitis, allergy, asthma, other seasonal allergic rhinitis; (2) inflammatory diseases, including noninfective gastroenteritis and colitis, acute atopic conjunctivitis, osteoarthritis, and unspecified chronic bronchitis; (3) mental disorders with impairment (MDI), including comorbid mental disorders, schizophrenia and sleep disorder; (4) malignant tumors, including malignant neoplasm of prostate, malignant (primary) neoplasm and malignant neoplasm of breast; (5) other symptoms and diseases, other symptoms and diseases, such as wheezing, pruritus and gout. Notably, non-infective gastroenteritis and colitis showed the strongest correlation (OR: 38.39, 95% CI: 3.08-478.01) among the 33 ADADs. We identified 33 ADADs based on the NHANES (2013-2018) dataset, which provide new insights into understanding the development of these ADADs associated with AD.

A multidimensional analysis of prognostic factors in atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin condition with a high prevalence worldwide and multifaceted pathogenesis. In general, patients with moderate to severe AD often experience relapse after discontinuing treatment. Therefore, to understand the possible factors of chronic relapse of AD and to look for biological markers that predict the relapse or poor prognosis of AD will be helpful for clinical treatment. Mutations in genes such as FLG, SPINK5, STAT, KIF3A, claudin-1, Ovol1, and HLA-DRB1 offer new insights into the genetic basis of AD. Routine factors may help improve patient lifestyle, highlight the importance of environmental influences (including psychological stress), and support clinicians in optimizing anti-infective treatment strategies. The inflammatory axis (CD30-CD30L axis, IL-9-IL-18 axis) provides new insights into the inflammatory pathways of AD and may be a target for future therapies. Low NKG2D expression may have adverse effects on prognosis. Prognostic biomarkers can play an important role in treatment monitoring, disease progression and recurrence, and provide the possibility for more personalized treatment.

A topical Chinese herbal inhibits pruritus and skin inflammation via neural TRPM8 in atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic, itchy, and inflammatory skin disease. The neuroimmune concept of itch involves aberrant immune responses and neural activities. Chinese herbal medicine has been demonstrated to alleviate AD symptoms, but the underlying mechanisms remain not fully understand.

PURPOSE

Chushizhiyang (CS) ointment is a topical treatment consisting of Chinese herbal ingredients. We aimed to study the underlying mechanism of CS on treating AD.

METHOD

To investigate the therapeutic efficacy of CS, we utilized a well-established atopic dermatitis mouse model, administering CS ointment topically to the ears. To unravel the underlying mechanisms, we employed a multifaceted approach, including behavioral assay, network pharmacology analysis, RNA-sequencing analysis, neural tracing, and calcium imaging. Additionally, transient receptor potential (TRP) M8-deficient mice were employed to validate the specific targets of CS.

RESULTS

By employing a murine model of AD-like disease, we found that CS ointment can reduce skin inflammation and inhibit scratching behavior. Importantly, its capacity to alleviate itch-induced scratching surpasses that of topical steroid, a positive control treatment. The RNA-sequencing analysis of the affected skin revealed that the differentially expressed genes were enriched in neuroactive pathways that include ion channels particularly TRPM8. Calcium imaging demonstrated that CS ointment is capable of activating TRPM8-positive sensory neurons. Using transgenic animals, we found that CS ointment exhibited its anti-inflammatory or anti-pruritic effects only when TRPM8 is functional intact. Additionally, CS treatment reduced neuronal activities in wild-type, rather than TRPM8-compromised animals.

CONCLUSION

Our findings suggest that topical Chinese herbals participate in neuroimmune mechanisms for AD-like disease via TRPM8.

Selected traditional Chinese herbal medicines for the treatment of atopic dermatitis - research progress on the effect and mechanism of actions

Atopic dermatitis (AD) is a common chronic, recurrent, inflammatory skin disease characterized by pruritus, lichen-like changes and dry skin. Due to the complex pathogenesis of AD, its mechanism is primarily associated with genetic, skin barrier dysfunction, environmental, and immune factors. AD has been routinely treated with glucocorticoids, antihistamines, local immunomodulators, biological agents, and small molecules; however, the side effects are significant, and the treatment efficacy is limited. In recent years, traditional Chinese medicine (TCM) has gradually been widely used in the treatment of AD. Many studies have shown that TCM mainly regulates inflammatory cytokines, gut microbiota and the immune system. Therefore, it plays a crucial role in the treatment of AD. The treatment of atopic dermatitis using TCM is characterized by targeting multiple pathways and multiple targets, and it demonstrates significant therapeutic effects. This paper reviews the pathogenesis of AD and reports the efficacy of TCM on AD (including TCM prescription, single TCM, treatment of TCM metabolites), which provides a theoretical basis for TCM treatment of AD. TCM has certain therapeutic effects on AD. It can alleviate and treat AD in various ways. We should base our differentiation on syndrome differentiation and treatment differentiation. With the help of modern medicine, the clinical efficacy of TCM in treating AD can be improved.

The Relationship Between Bacterial Flora in Saliva and Esophageal Mucus and Endoscopic Severity in Patients with Eosinophilic Esophagitis

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease characterized by esophageal dysfunction and eosinophilic inflammation of the esophageal mucosa. In this study, we investigated the bacterial flora in saliva and esophageal mucus in patients with EoE and examined the relationship between EoE disease activity and mucosal cytokine expression, involving patients with active and inactive EoE (A-EoE and I-EoE, respectively). A-EoE was defined as a peak eosinophil count > 15/high-power field, according to the 2025 consensus guidelines. Saliva samples were collected from patients before the endoscopic examination. Brushing samples were collected from the distal esophagus of patients with EoE during endoscopic procedures. The degree of EoE inflammation was assessed using the EoE endoscopic reference score (EREFS). The samples were profiled using the Illumina MiSeq platform. The V3-V4 regions of the 16S rRNA gene (460 bp) were amplified using tailed PCR. Fifty-nine patients were enrolled, including eight with I-EoE, seventeen with A-EoE, and twenty-eight non-EoE controls. Major bacterial genera such as Streptococcus, Prevotella, Veillonella, and Haemophilus were detected in both the oral cavity and esophagus. Compared with the control group, the active EoE group had significantly more Prevotella spp. in the saliva and esophageal mucosa. Conversely, significantly fewer Neisseria spp. were found in the saliva and Streptococcus spp. in the esophageal mucosa of patients with active EoE. The EREFS of EoE and Streptococcus were inversely correlated. This study elucidated the characteristics of bacterial flora in the saliva and esophageal mucosa of patients with EoE.

Investigating the complex roles of immunocyte phenotypes in the pathogenesis of dermatitis: a causal inference Mendelian randomization analysis

The etiology of dermatitis involves complex interactions between immune cells, genetics, and environmental factors. While immunocyte phenotypes have been linked to various forms of dermatitis, their causal role remains unclear. We conducted a two-sample Mendelian randomization (MR) analysis to investigate the causal effects between 731 immunocyte phenotypes and four types of dermatitis: atopic dermatitis, contact dermatitis, infective dermatitis, and seborrhoeic dermatitis. Genetic variants were used as instrumental variables, and the inverse variance-weighted (IVW) method was employed to assess causality. Sensitivity analyses were performed to ensure robustness. The forward MR analysis identified significant associations between 22 immunocyte phenotypes and atopic dermatitis, 8 phenotypes with contact dermatitis, 5 with infective dermatitis, and 6 with seborrhoeic dermatitis. The reverse MR analysis suggested potential bidirectional interactions of atopic dermatitis and CD3 on CD28 + CD45RA- CD8br (OR = 0.924, P = 0.012). This study revealed causal relationships between specific immunocyte phenotypes and dermatitis subtypes, providing novel insights into the immunopathogenesis of dermatitis and potential therapeutic targets.

Melatonin treatment increases skin microbiota-derived propionic acid to alleviate atopic dermatitis

BACKGROUND

Melatonin has been reported to relieve the inflammatory symptoms and improve sleep disturbance in patients with atopic dermatitis (AD). Recent studies showed that melatonin produced beneficial effects by remodeling intestinal microbiota composition; however, whether the beneficial effects of melatonin in AD were mediated by the modulation of skin microbiota remains unclear.

OBJECTIVE

We sought to investigate the mechanism by which melatonin treatment-induced changes in the skin microbiota composition further alleviated AD.

METHODS

The changes in skin bacterial composition after melatonin treatment were detected by 16S-rRNA sequencing. Further mechanisms were explored in calcipotriol (MC903)-induced AD mice and HaCaT cells through skin microbiota transplantation, quantification detection of short-chain fatty acids, transcriptome and single-cell sequencing analysis, quantitative RT-PCR, Western blotting, and Cell Counting Kit-8 assay.

RESULTS

We demonstrated that melatonin reshaped the skin microbiota in AD mice. The transplantation of skin microbiota from melatonin-treated mice alleviated AD symptoms in mice. Skin microbiota-derived short-chain fatty acids, especially propionic acid, were increased in the skin of melatonin-treated AD mice, which further inhibited FABP5 expression to alleviate AD. Propionic acid also inhibited FABP5 expression in HaCaT cells, which was reversed by the treatment of GPR43 inhibitor GLPG0974. GLPG0974 also blocked the therapeutic effects of melatonin on AD mice.

CONCLUSIONS

Our study demonstrated that melatonin alleviates AD through the skin microbiota/propionic acid/GPR43/FABP5 axis, highlighting a novel role of melatonin as a modulator of skin microbiota to alleviate AD.

Atopic Dermatitis in Adults: Focus on Topical Therapy

Objective To review the topical therapies for adults, including older adults, with atopic dermatitis. A background on atopic dermatitis in adults, overview of treatment recommendations, and the pharmacists' role for care is included. Data Sources Articles indexed in PubMed, Cochrane Reviews, and Google Scholar in the past 10 years using the search terms atopic dermatitis, atopic dermatitis and treatment, and atopic dermatitis and adults were reviewed. Current guidelines and manufacturers' prescribing information were reviewed. Primary sources were used to locate additional resources. Study Selection/Data Extraction Forty-five publications were reviewed and criteria supporting the objectives identified useful resources. Data Synthesis Selected literature included practice guidelines, review articles, research articles, product prescribing information, and drug information databases. Conclusion Atopic dermatitis is a common chronic inflammatory cutaneous disease that may present at any age. Atopic dermatitis has a relapsing course with active disease followed by periods of remission. Atopic dermatitis is not curable, but available and recommended regimens can control patient symptoms. Topical therapies are the preferred treatment and are able to control atopic dermatitis in most adults. Topical moisturizers are the mainstay of therapy. Despite regular use of a moisturizer, most patients will need a topical anti-inflammatory agent to control disease flares. The Food and Drug Administration-approved topical anti-inflammatory agents include the corticosteroids, calcineurin inhibitors, a phosphodiesterase-4 enzyme inhibitor, and a Janus Kinase inhibitor. Pharmacists are in a unique position to counsel patients about the appropriate use and benefits and risks of atopic dermatitis therapies.

The future of topical JAK inhibitors in the treatment of atopic dermatitis

INTRODUCTION

Atopic dermatitis (AD) is a chronic inflammatory skin condition, rising in prevalence and significantly impacting quality of life. Janus kinase (JAK) inhibitors are small molecules targeting the JAK-STAT signaling pathway, responsible for immune response and cell proliferation. Therapy with topical JAK inhibitors (JAKinibs) improves AD itch and skin lesions and is well tolerated with no major side effects, making it an interesting novel therapy for AD.

AREAS COVERED

This review provides a comprehensive look at the available research on topical JAK inhibitors, primarily for atopic dermatitis, based on clinical trial outcomes.

EXPERT OPINION

In this review, we summarize research on topical JAKinibs, including ruxolitinib, tofacitinib, delgocitinib, cerdulatinib, and bredocitinib, which target multiple cytokine pathways and have been shown to reduce the itch and inflammation. Their low bioavailability contributes to infrequent and mild side effects. The main limitation of predominantly short-term studies is that the long-term effects of JAK inhibitor therapy are not yet fully known. The body of research is growing, and more information about their effectiveness and safety is being added each year.

Interleukin-4 and Atopic Dermatitis: Why Does it Matter? A Narrative Review

Atopic dermatitis (AD) is a common chronic inflammatory skin condition that significantly impairs patients' quality of life as a result of intense itching and persistent eczematous lesions. Although AD has a multifaceted etiology-including genetic predisposition, environmental triggers, barrier dysfunction, and dysregulated immune responses-interleukin-4 (IL-4) has a recognized central role in its pathogenesis. This narrative review explores the role of IL-4 in the pathophysiology of AD, its contribution to the atopic march, and the therapeutic impact of IL-4 inhibition. IL-4 plays a critical role in skin barrier dysfunction, dysbiosis, pruritus, and inflammation, all of which contribute to the debilitating symptoms of AD. Moreover, IL-4 is implicated in other atopic conditions, such as asthma, allergic rhinitis, and food allergies, underscoring its role beyond AD and its importance in the atopic march. Recent advances in targeted therapies, particularly IL-4/IL-13 signaling inhibitors, have changed AD management. Dupilumab, an IL-4 receptor antagonist, has demonstrated significant efficacy in reducing AD symptoms and enhancing patient outcomes in both children and adults. In addition to symptomatic relief, suppressing IL-4 signaling may also offer potential for disease modification, altering AD's progression and possibly preventing the onset of other atopic conditions. This review highlights the crucial role of IL-4 as a therapeutic target in AD. By understanding the role of IL-4 in AD pathogenesis and exploring the therapeutic implications of targeting IL-4 pathways, this work can contribute to guide future research concerning treatment approaches and also emphasize the need for early and targeted interventions to mitigate disease impact and ultimately improve patient quality of life.

Safety and Effectiveness of Upadacitinib in Patients with Moderate-to-Severe Atopic Dermatitis Who Smoke: a 2-Year Real-Life Multicenter Study

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin condition that significantly impairs the quality of life. Recent advancements in systemic therapies, such as Janus kinase (JAK) inhibitors, offer very effective new treatment options. However, concerns regarding potential adverse events, including cardiovascular and thromboembolic risk, have emerged from clinical studies and call for further real-life investigations. This has highlighted the need to establish specific risk categories, such as tobacco smokers.

OBJECTIVE

This study aims to evaluate the safety and effectiveness of upadacitinib, a JAK1 inhibitor, in patients who smoke with moderate-to-severe AD over a 2-year treatment period, comparing outcomes with patients who do not smoke.

PATIENTS AND METHODS

A retrospective multicenter study was conducted across 12 dermatology departments in Italy, including 375 patients treated with upadacitinib. The presence and intensity of smoking habits as well as effectiveness scores and safety data were collected.

RESULTS

Patients who smoke accounted for 36.8% of the sample. Two thromboembolic events in patients who do not smoke were recorded in the 2-year (median follow up of 52.6 weeks) observation period. The most common adverse event was acneiform eruption (12.4% of patients after 104 weeks). No significant differences related to safety emerged regarding the presence or absence of a smoking habit. Drug survival was very high with no differences between the two cohorts (83.5% after 104 weeks for patients who smoke).

CONCLUSIONS

This study suggests that upadacitinib is a safe and effective treatment for moderate-to-severe AD in presence of tobacco smoke, with no significant differences in safety or effectiveness compared with patients who do not smoke.

Exploring the shared genetic mechanisms of atopic dermatitis and alopecia areata via bioinformatics approaches

Atopic dermatitis (AD) and alopecia areata (AA) are chronic inflammatory skin diseases. While studies suggest a possible immune defense mechanism link between the two, the causal relationship remains unclear, and current methodologies have limitations. This study aims to investigate the causal relationship between AD and AA using genome-wide association study statistics from the Integrative Epidemiology Unit Open Genome-Wide Association Study (IEU Open Gwas) project. We utilized the inverse variance weighting (IVW) method as our primary analysis approach for assessing the causal association between AD and AA. To enhance the robustness of our findings, we also employed supplementary validation methods, including the weighted median, MR-Egger method, and other analytical approaches. Our analysis revealed a significant increase in the risk of AA associated with single-nucleotide polymorphisms (SNPs) linked to AD (odds ratio (OR) = 1.84, 95% confidence interval (CI): 1.19-2.85, p-value (p) = 0.006). While MR-Egger analysis did not show a significant association (OR = 1.04, 95% CI: 0.29-3.68, p = 0.957), weighted median analysis demonstrated a significant association (OR = 2.08, 95% CI: 1.16-3.71, p = 0.013). Additionally, MR-Egger intercept and MR-PRESSO analysis showed no evidence of potential pleiotropy or horizontal pleiotropy between AD and AA. This study indicates that AD increases the risk of AA, providing valuable insights into the pathogenesis and prevention of these two diseases. Future research should explore the underlying mechanisms to better understand this relationship.

Canthaxanthin ameliorates atopic dermatitis in mice by suppressing Th2 immune response

Atopic dermatitis (AD) is a prevalent chronic inflammatory skin disorder characterized by intense pruritus and complex immunopathogenic mechanisms. Recent evidence has highlighted the critical link between dysregulated intestinal microecology and altered immune responses in AD progression. As essential components of the intestinal microenvironment, metabolites play pivotal roles in various physiological processes. Through metabolomic profiling in an AD mouse model, we identified a significant reduction in canthaxanthin (CTX), a bacterial-derived metabolite naturally present in many foods, in AD mice compared to healthy controls. To investigate the therapeutic potential of CTX, we established an AD model by repeatedly applying 2,4-dinitrochlorobenzene (DNCB) to the ears and dorsal skin of mice, successfully inducing AD-like symptoms and lesions. Notably, oral administration of CTX significantly attenuated skin inflammation and reduced serum IgE levels in this DNCB-induced AD model. Both in vivo and in vitro studies demonstrated that CTX treatment effectively suppressed Th2 immune responses. Mechanistically, we found that CTX significantly inhibited the activation of the JAK2-STAT6 signaling pathway in Th2-polarized T cells. Our findings not only demonstrate the therapeutic efficacy of CTX in AD but also elucidate its molecular mechanism in modulating T helper cell subset balance. These insights suggest that CTX could serve as a promising therapeutic agent for AD and potentially other Th2 response-mediated immune disorders.

Reductive Adjuvant Nanosystem for Alleviated Atopic Dermatitis Syndromes

Atopic dermatitis (AD) is a recurrent and chronic inflammatory skin condition characterized by a high lifetime prevalence and significant impairment of patients' quality of life, primarily due to intense itching and discomfort. However, current pharmacological interventions provide only moderate efficacy and are frequently accompanied by adverse side effects. The immune-pathogenesis of AD involves dysregulation of the Th2 immune response and exacerbation of inflammation related to excessive reactive oxygen species (ROS). Therefore, to address these issues, in this study, we targeted the upstream pathogenesis by designing a pro-Th1 adjuvant nanoemulsion loaded with poly(I:C) and encapsulated with the ROS-scavenger vitamin E, termed PV-NE. PV-NE effectively rebalanced the Th1/Th2 immune response and reduced ROS levels both in vivo and ex vivo, leading to the restoration of immune balance in AD-affected skin and alleviation of symptoms such as lichenification and erythematous patches. In conclusion, our development of the reductive adjuvant nanosystem PV-NE demonstrates its biocompatibility and efficacy in combating AD progression without the use of immunosuppressant glucocorticoids. This has the potential to significantly impact the design and enhancement of pharmacotherapy in future clinical research aimed at curing AD.

Assessing the Clinical Efficacy of Dupilumab and Its Impact on the Quality of Life of Adult Atopic Dermatitis Patients: A Systematic Review

Dupilumab, a monoclonal antibody, acts as a dual-action inhibitor that effectively suppresses interleukin-4 (IL-4) and interleukin-13 (IL-13) secretion, which plays an important role in type 2 inflammation. Atopic dermatitis (AD), also known as eczema, is a chronic inflammatory skin disorder that affects both adults and infants. The primary objective of this systematic review was to evaluate the clinical efficacy of dupilumab and the quality of life (QOL) of atopic dermatitis adult patients on dupilumab. Although adults experience a lower percentage of AD as compared to children globally, this disease should be addressed to improve the treatment of this condition in adults. The need for the study arises from the fact that there is a dearth of data regarding the efficacy of dupilumab in atopic dermatitis, particularly in the adult population. An extensive search was conducted using PubMed, Turning Research Into Practice (TRIP), and Cochrane Central Register of Controlled Trials (CENTRAL) and included studies published between 2018 and 2025 in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines 2020. The Medical Subject Headings (MeSH) terms and Boolean operators used were "Dupilumab" OR "Dermatitis, Atopic". All randomized controlled trials (RCTs) were included in this systematic review. Nine full-text articles were ultimately considered, and critical appraisal was performed thereon. Dupilumab at a dose of 300 mg once every two weeks (q2w) and 300 mg once weekly (qw) were effective in treating atopic dermatitis by improving symptoms of pruritus, pain, and depression and preventing the spread of the disease. The quality of life (QOL) improved significantly, and the rate of atopic dermatitis hospitalization decreased after the use of dupilumab.

Abrocitinib-associated adverse events: a real-world pharmacovigilance study using the FAERS database

BACKGROUND

Atopic dermatitis (AD) is a common chronic inflammatory skin disease. Janus kinase (JAK) modulates cytokines involved in AD pathophysiology, and JAK inhibitors have emerged as effective pharmacotherapeutic remedies for AD. Abrocitinib, an oral selective inhibitor of JAK1, is indicated for the management of moderate-to-severe AD. The current study evaluated the adverse events (AEs) associated with abrocitinib in a real-world setting.

METHODS

To quantify the signals of abrocitinib-associated AEs, we used the US Food and Drug Administration Adverse Event Reporting System (FAERS) for this pharmacovigilance study with two established pharmacovigilance methods.

RESULTS

A total of 1071 AEs of abrocitinib were investigated as the primary suspected from the FAERS to detect and characterize relevant safety signals. The analysis revealed 85 signals for abrocitinib. The most common AE for abrocitinib was drug ineffective. The signal strength of eczema herpeticum was 515.87 (277.80-957.98) and 510.59 (5148.65) and exhibited the highest strength for abrocitinib. Rare AEs such as aggravated condition, pruritus, and hypersensitivity were not listed on the label, and attention to these AEs is required.

CONCLUSION

The analysis of the AE signals may provide support for clinical monitoring and risk identification of abrocitinib.

Preventing NLRP3 inflammasome activation: Therapeutic atrategy and challenges in atopic dermatitis

Atopic dermatitis (AD) is a prevalent inflammatory skin disorder characterized by its chronic, persistent, and recurrent nature. The pathophysiology of this condition is complex, involving various factors including cell-mediated immune responses, compromised skin barrier function, and alterations in hypersensitivity reactions. These components synergistically contribute to the perpetuation of the bothersome "itch-scratch-itch" cycle. Recent research has highlighted the significant role of the NLRP3 inflammasome in the development of AD and other inflammatory conditions. Current research indicates that the NLRP3 inflammasome plays a pivotal role in both the acute and chronic phases of AD by modulating the Th2/Th1 immune deviation. Moreover, the pharmacological suppression of NLRP3 has shown promising results in mitigating the pathological aspects of AD. This review outlines potential drug development strategies that target the NLRP3 inflammasome as a therapeutic approach for AD and the challenges faced in this endeavor.

Efficacy of a Video Education Program Regarding Basic Skin Care in Pediatric Atopic Dermatitis: A Randomized Controlled Trial

BACKGROUND

Basic skin care education holds the potential to improve clinical outcomes in pediatric atopic dermatitis (AD). However, evidence is lacking on the efficacy of video education for patient guardians in Thailand to reduce AD disease severity.

OBJECTIVES

To compare the efficacy of a video education program for guardians of pediatric AD patients versus a control group by assessing the severity score of AD (SCORAD), transepidermal water loss (TEWL), and skin hydration (SH).

METHODS

A single-blinded, randomized controlled trial was conducted at a tertiary hospital from June 2023 to February 2024, involving AD patients aged < 18 years and their guardians. Both groups received standard treatment, and the educational group received an additional video education program. SCORAD, TEWL, SH, pruritus, sleeplessness, and parental/guardian confidence and knowledge accuracy were assessed at enrollment and a 4-week follow-up.

RESULTS

Seventy patients (educational:control group, 34:36) with a median age of 3.1 years were enrolled. The groups exhibited no significant demographic or disease severity differences between them. At follow-up, the educational group showed significant SCORAD improvement compared to the control group (mean difference -10.93 [95% CI -16.92--4.95]; p < 0.001). SH (mean difference 3.82 [95% CI -2.7-10.33]; p = 0.25) and TEWL (mean difference -1.24 [95% CI -5.72-3.24]; p = 0.58) did not differ significantly.

CONCLUSIONS

Video education demonstrated efficacy in significantly reducing SCORAD. While there were improvements in SH and TEWL in patients in the education group, these improvements were not statistically significant. Further investigation with a larger sample size is warranted.

TRIAL REGISTRATION

Thai Clinical Trials Registry (TCTR): TCTR20230524001.

Acupuncture for atopic dermatitis: a systematic review and meta-analysis

OBJECTIVES

Atopic dermatitis is a chronic, relapsing, inflammatory skin disease that impacts patients' quality of life and imposes substantial economic burdens on their families. Acupuncture holds promise as a viable treatment option for atopic dermatitis. This review aimed to evaluate the effect of acupuncture on atopic dermatitis.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, CENTRAL, the China National Knowledge Infrastructure, WanFang and VIP databases were searched through 17 September 2023, together with an updated search on 15 October 2024.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included randomised controlled trials (RCTs) about acupuncture for atopic dermatitis. The primary outcome was the SCORing Atopic Dermatitis (SCORAD) score. The secondary outcomes were the eczema area and severity index (EASI) score, the visual analogue scale (VAS) score for pruritus, the dermatology life quality index (DLQI) score, serum IgE level and adverse events (AEs).

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers conducted separate searches of the databases, assessed eligible articles for inclusion and employed the Cochrane Collaboration's tool for assessing the risk of bias. The analyses were performed using RevMan 5.3 and Stata 13.0 software. The mean difference (MD) with 95% CI was employed to analyse continuous outcomes.

RESULTS

Eight studies with 463 participants were included. The meta-analysis indicated significant differences in the SCORAD score (MD=-10.61, 95% CI -17.77 to -3.45, p=0.004), the VAS score for pruritus (MD=-14.71, 95% CI -18.20 to -11.22, p<0.00001) and the DLQI score (MD=-2.37, 95% CI -3.57 to -1.18, p<0.0001), but no significant differences in the EASI score (MD=-3.95, 95% CI -8.35 to 0.45, p=0.08) and the IgE level (MD=-160.22 U/mL, 95% CI -334.13 to 13.68, p=0.07) between treatment and control. The differences in the SCORAD score and the VAS score for pruritus reached minimal clinically important differences. No serious AEs were reported.

CONCLUSIONS

Acupuncture might be an effective and safe treatment for atopic dermatitis. Due to the limited quantity and quality of the included studies, it is recommended to conduct multicentre, large-scale and high-quality RCTs to further confirm the findings.

PROSPERO REGISTRATION NUMBER

CRD42023470643.

Single-Atom Catalysts with Isolated Cu1-N4 Sites for Atopic Dermatitis Cascade Catalytic Therapy via Activating PPAR Signaling

Atopic dermatitis (AD) is one of the most common allergic skin disorders affecting over 230 million people worldwide, while safe and efficient therapeutic options for AD are currently rarely available. Reactive oxygen species (ROS) accumulation plays a key role in AD's disease progression. Therefore, a novel single-atom catalyst is designed with isolated Cu1-N4 sites anchored on carbon support (Cu1-N4 ISAC), featuring triple antioxidant enzyme-mimicking activities, for efficient AD cascade catalytic therapy (CCT). The excellent superoxide dismutase (SOD)-, glutathione peroxidase (GPx)-, and ascorbate peroxidase (APx)-like activities of Cu1-N4 ISACs enable the sequential conversion of O2•- to H2O2 and then to harmless H2O, thereby protecting keratinocytes from oxidative stress damage. Notably, two novel experimental methods are developed to directly prove the SOD-GPx and SOD-APx cascade catalytic activities for the first time. In vivo experiments show that Cu1-N4 ISACs are more potent than a recommended typical medicine (halcinonide solution). Additionally, RNA sequencing and bioinformatic analysis reveal that Cu1-N4 ISACs reduce inflammation and inhibit ROS production by activating PPAR signaling, which is aberrantly reduced in AD. Therefore, the synthesized catalytic medicine offers an alternative to alleviate AD and has the potential to serve as PPAR agonists for treating similar diseases.

Anti-Atopic Dermatitis Effect of Azalomycin F on 2,4-Dinitrofluorobenzene-Induced Mice and Potential Mechanism

Azalomycin F (AZF) is a kind of antibiotic with antifungal and antibacterial activities, as well as anti-inflammatory and anti-tumor activities. In this study, we evaluated the effects of AZF on atopic dermatitis (AD) and its possible molecular mechanisms. Mice with 2,4-dinitrofluorobenzene-induced AD-like skin lesions were topically treated with 10-30 mg/kg AZF on their dorsal skin for 12 days. Observations focused on skin lesion scores, the frequency of scratching, and histopathological alterations in the skin. In addition, IgE and inflammatory cytokine levels in serum were assessed. The results indicated that topical application of 10-20 mg/kg AZF could reduce skin lesion scores and scratching frequencies in AD mice, while 15-20 mg/kg AZF decreased epidermal thickness and mast cell infiltration. Additionally, the serum levels of IgE, IFN-γ, IL-4, TSLP and IL-1β were reduced with 10-20 mg/kg AZF treatment. Moreover, RNA-Seq was employed to reveal the potential molecular mechanisms underlying anti-AD effects of AZF. KEGG enrichment analysis revealed that the most significantly differentially expressed genes are predominantly enriched in signaling pathways such as NF-κB and TNF. Protein-protein interaction network analysis identifies the key genes including Il1b, Tnf, and Cxcl1. In summary, 15 mg/kg AZF effectively alleviates the inflammatory response in AD mice, and the potential mechanism may involve the regulation of key signaling pathways like NF-κB and TNF, thereby reducing inflammatory factor levels and eliciting an anti-inflammatory effect. These findings provide valuable scientific evidence for the development of novel natural drugs for the treatment of AD.

Effects of Huang-Lian-Jie-Du decoction on improving skin barrier function and modulating T helper cell differentiation in 1-chloro-2,4-dinitrobenzene-induced atopic dermatitis mice

Background: Atopic dermatitis (AD) is among the most frequently encountered skin diseases, bothering a considerable number of patients. Today, corticosteroids and antihistamines are among the numerous drugs applied for the therapy of AD. However, lengthy use of them contributes to side effects, such as physiological changes in skin. As an alternative and supplementary therapy, traditional Chinese medicine has become a trend for AD treatment. Huang-Lian-Jie-Du decoction (HLJDD), a renowned herbal formula has been employed to treat inflammatory diseases such as AD. However, its role in regulating immunity in AD remains unclear. The object of this study was to elucidate the efficacy of HLJDD and reveal the implicit mechanism from an immunological perspective in AD-like mice. Methods: In brief, 1-chloro-2,4-dinitrobenzene (DNCB) for the sensitization phase (1% DNCB) and stimulation phase (1.5% DNCB) were applied for BALB/c mice. HLJDD and dexamethasone (DXMS) were administered orally to the mice. Mice skin and spleens were collected to evaluate the efficacy of HLJDD. 16S rRNA sequencing was applied to evaluate the commensal microbiota changes in skin and fecal. In vitro, spleen CD4+ T cells and bone marrow-derived mast cells (BMMCs) were co-cultured to explore the modulation of HLJDD in T helper (Th) cells phenotyping. Results: HLJDD showcased a substantial amelioration in skin through the upregulation of FLG, LOR, AQP3, and reducing scratching behaviors in AD-like mice, Also, the quantity of infiltrated mast cells (MCs), pruritus-related mRNA were decreased. In addition, the expression of OX40/OX40L was decreased by HLJDD, which was critical in Th-cell phenotyping. With the treatment of HLJDD, Th1/Th2 and Th17/Treg ratios in AD-like mice became balanced. The structure of commensal microbiota in AD-like mice was affected by HLJDD. HLJDD could also improve the imbalance of Th17/Treg in vitro. Conclusion: HLJDD could improve the symptoms of AD-like mice by alleviating the scratching behaviors via decreased Th2 and pruritus-related mRNA expression. HLJDD also enhanced the relative diversity of skin microbiota and changed the structure of intestinal microbiota. An in-depth study found that HLJDD could balance the ratio of Th1/Th2, Th17/Treg in AD-like mice, and Th17/Treg in vitro by regulating the OX40/OX40L signaling pathway.

The association between pruritic dermatoses and inflammatory factors on sleep disorders: a cross-sectional study of the National Health and Nutrition Examination Survey (NHANES)

Pruritic dermatoses and sleep disorders have significant impacts on the health and quality of life of patients. Inflammatory conditions may lead to the sensation of itching. This study was to evaluate the association between pruritic dermatoses and inflammatory factors on sleep disorders. Data in the cross-sectional study were extracted from the National Health and Nutrition Examination Survey. The study population was divided into participants with and without sleep disorders. Pruritic dermatoses were assessed by the participant's self-report. Inflammatory factors included white blood cell count (WBC), lymphocyte count (LYM) and prognostic nutritional index (PNI). Logistic regression models were used with odds ratios and confidence intervals. The attributable proportion of interaction (AP) was utilized to assess the interaction between pruritic dermatoses and inflammatory factors on sleep disorders. Totally, 3,520 participants were included and 214 (6.08%) had sleep disorders. Pruritic dermatoses were associated with sleep disorders after adjusting for gender, age, race, marital status, body mass index, drinking, smoking, asthma, hay fever, allergy, depression and caffeine. LYM was associated with sleep disorders when inflammatory factors were divided by median. The interaction between participants without pruritic dermatoses and PNI < median on sleep disorders was observed compared to participants without pruritic dermatoses and PNI > median. Pruritic dermatoses were significantly associated with sleep disorders. We also found that a high level of PNI had an enhanced effect on the relationship between pruritic dermatoses and sleep disorders. Clinicians should focus on the potential sleep-related risks and changes in inflammatory factors in patients with pruritic dermatoses and intervene in time.

Patho-immunological mechanisms of atopic dermatitis: The role of the three major human microbiomes

Atopic dermatitis (AD) is a genetically predisposed allergic inflammatory dermatosis with chronic, pruritic, and recurrent features. Patients with AD have dry and itchy skin, often accompanied by chronic eczematous lesions, allergic rhinitis, or asthma, which has a considerable impact on their daily lives. With advances in genome sequencing technology, it has been demonstrated that microorganisms are involved in this disease, and the microorganisms associated with AD are attracting considerable research attention. An increasing number of studies conducted in recent years have demonstrated that an imbalanced microbiome in AD patients has substantial impact on disease prognosis, and the causes are closely tied to various immune mechanisms. However, the involvement of microorganisms in the pathogenesis of AD remains poorly understood. In this paper, we review the advances in research on the immunological mechanisms of the skin microbiome, intestinal microbiome, and lung microbiome that are related to AD prognosis and immunotherapy protocols. It is hoped that this approach will lay the foundation for exploring the pathogenesis of and emerging treatments for AD.

Plasma-Activated AVC Hydrogel for Reactive Oxygen and Nitrogen Species Delivery to Treat Allergic Contact Dermatitis

Allergic contact dermatitis (ACD) is a common inflammatory skin disease that accounts for approximately 20% of all occupational skin diseases. As an adverse and recurrent inflammatory dermatological agent, ACD shows insufficient response to current therapies largely owing to abnormal inflammatory activation and accompanying bacterial infection in lesions. Cold atmospheric plasma is a noninvasive fledgling reactive oxygen and nitrogen species (RONS)-based therapeutic technique for ACD treatment; however, its clinical adoption has been hindered due to the risk of electrical burns and insufficient delivery of the plasma-generated RONS. To address these limitations, we constructed plasma-activated AVC (PA-AVC) hydrogels loaded with plasma-generated RONS for ACD treatment as an alternative to the common direct plasma irradiation treatment. The proposed PA-AVC hydrogels were produced on a biodegradable acryloyldimethylammonium taurate/VP copolymer (AVC) with the aid of a novel air discharge plasma without the involvement of any catalyst. In vitro data showed that abundant RONS were produced and incorporated into the PA-AVC hydrogels via complex gas-liquid reactions between the air discharge plasma and hydrosolvent; additionally, the PA-AVC hydrogels exhibited excellent storage, slow release and transdermal delivery of RONS as well as good antibacterial effects. Moreover, in vivo experiments demonstrated that PA-AVC hydrogels effectively alleviated the ACD symptoms, such as skin redness and swelling, reduced epidermal thickening and inhibited mast cell infiltration and IL-9, TNF-α, and TSLP expression with no evident systemic toxicity. Our results revealed that long-acting plasma-activated AVC hydrogels could be effective therapeutic agents for local ACD treatment.

Differences in the permeation of Licoricchalcone A-polysaccharide self-assembled nanoparticles on healthy and DNCB-induced atopic dermatitis in Balb/c mice

Nanoformulation have been widely used in skin and transdermal drug delivery. However, the differences in integral nanoparticles absorption in healthy and diseased skin have not yet fully analyzed. The present study attempted to explore the percutaneous absorption of drugs via lesional skin by using atopic dermatitis (AD) as a model, dinitrochlorobenzene (DNCB) induced AD-like skin. In here, the small molecules of insoluble Licoricchalcone A (LA) and macromolecules glycyrrhizin polysaccharide were used to prepare LA-polysaccharide self-assembled nanoparticles (GPA-SANs) by micro-precipitation. An environment-responsive dye, P4, was loaded into SAN to track the transdermal translocation of the nanoparticles, while the drug marked with coumarin 6 (C6). Compared to healthy skin, the permeability of GPA-SANs on AD-like skin is stronger, which may be due to damage to the stratum corneum of the AD-like skin and increased intercellular spaces, resulting in an increased permeability coefficient. Therefore, the storage of nanoparticles and their diffusion at the lesion site also increased accordingly. CLSM shown that the fluorescence of P4 and C6 is observed to concentrate around the hair follicles and disseminate in the surrounding area in both AD-affected and healthy skin. It can be clearly seen that fluorescence signal of C6 in the intercellular spaces of the dermis and epidermis of AD-like skin, indicating that nano-drug on the disease skin can penetrate through the intercellular pathway to achieve therapeutic. The focus of the present study is to assess the permeability of healthy and disease skin, discuss their characteristics and discrepancy, aiming to provide a reference for the further study of nano-formulations in transdermal delivery.

Efficacy and Potential Mechanisms of Naringin in Atopic Dermatitis

Atopic dermatitis (AD) is one of the most prevalent chronic inflammatory skin diseases. Topical treatments are recommended for all patients regardless of severity, making it essential to develop an effective topical AD treatment with minimal side effects; We investigated the efficacy of topical application of naringin in AD and explored the possible mechanisms using an AD mouse model induced by 1-chloro-2,4-dinitrobenzene (DNCB). Clinical, histological, and immunological changes related to AD and Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling proteins in the skin tissues were measured as outcomes; Naringin treatment resulted in a significant improvement in dermatitis severity score and reduced epidermal thickness and mast cell count in the skin (p < 0.05). Naringin also demonstrated the ability to inhibit DNCB-induced changes in interleukin (IL) 4, chemokine (C-C motif) ligand (CCL) 17, CCL22, IL1β, interferon-gamma (IFN-γ), and tumor necrosis factor-alpha (TNF-α) levels by quantitative real-time polymerase chain reaction (qRT-PCR) and IL13 by enzyme-linked immunosorbent assay (ELISA) (p < 0.05). Western blot results exhibited the decreased JAK1, JAK2, STAT1, STAT3, phospho-STAT3, and STAT6 expression in the naringin-treated groups (p < 0.05); The findings of this study suggest that topical naringin may effectively improve the symptoms of AD and could be used as a therapeutic agent for AD.

Anti-inflammatory Capacity of a Medicinal herb extract, Anemarrhena asphodeloides, on In vivo and In vitro models-induced atopic dermatitis

Anemarrhena asphodeloides (AA) Bunge, a rhizomatous plant from the Liliaceae family, is traditionally utilized to manage inflammatory conditions. Nevertheless, its impact on atopic dermatitis (AD) and the associated molecular pathways have not yet been fully explored. This study explored the therapeutic effects of AA on AD both in vivo, using 2,4-dinitrofluorobenzene-induced NC/Nga mice, and in vitro, with tumor necrosis factor-α/interferon-γ-stimulated HaCaT keratinocytes. Topical application of AA ointment on the dorsal skin notably alleviated AD symptoms and skin lesions, enhanced the dermatitis score, and improved parameters such as the rate of trans-epidermal water loss, epidermal thickness, mast cell infiltration, systemic IgE levels, and cytokine expression. Furthermore, AA treatment significantly reduced serum levels of thymic stromal lymphopoietin (TSLP) and locally suppressed mRNA expression of thymus and activation-regulated chemokine (TARC) along with other relevant cytokines in affected skin. Both in vivo and in vitro applications of AA curtailed TSLP levels by inhibiting the expression of signal transducer and activator of transcription 6, a key regulator of pruritus and an initiator of mitogen-activated protein kinase signaling pathways. Additionally, AA affected the expression of tumor necrosis factor-like weak inducer of apoptosis/fibroblast growth factor-inducible 14, a pathway of interest in the study of cutaneous inflammatory diseases. Collectively, these findings propose that AA holds potential as an effective therapeutic agent for treating AD-induced skin inflammation.

Identification of novel hub genes and immune infiltration in atopic dermatitis using integrated bioinformatics analysis

The aim of this study was to identify key genes and investigate the immunological mechanisms of atopic dermatitis (AD) at the molecular level via bioinformatics analysis. Gene expression profiles (GSE32924, GSE107361, GSE121212, and GSE230200) were obtained for screening common differentially expressed genes (co-DEGs) from the gene expression omnibus database. Functional enrichment analysis, protein-protein interaction network and module construction, and identification of common hub genes were performed. Hub genes were validated using receiver operating characteristic curve analysis based on GSE130588 and GSE16161. NetworkAnalyst was used to detect microRNAs (miRNAs) and transcription factors (TFs) associated with the hub genes. The immune cell infiltration was analyzed using the CIBERSORT algorithm to further analyze the correlation between hub genes and immune cells. A total of 146 co-DEGs were obtained, showing significant enrichment in cytokine-cytokine receptor interaction and JAK-STAT signaling pathway. Seven hub genes were identified by Cytoscape and validated with external datasets. Subsequent prediction of miRNAs and TFs targeting these hub genes revealed their regulatory roles. Analysis of immune cell infiltration and correlation revealed a significant positive correlation between CCL22 expression and the number of dendritic cells activated. The identified hub genes represent potential diagnostic and therapeutic targets in the immunological pathogenesis of AD.

Trends in atopic dermatitis prevalence among the Chinese population (1990-2021) with projections for 2022-2030

BACKGROUND

Atopic dermatitis (AD) has the highest disease burden among all skin diseases. However, reports on AD prevalence trends in China are limited. This study aimed to investigate the time trends of AD prevalence in China from 1990 to 2021 and to explore the age and sex differences.

METHODS

Data were obtained from the Global Burden of Disease Study, 2021. We analyzed the annual percentage change in the crude prevalence rate and age-standardized prevalence rate (ASPR) of AD from 1990 to 2021 using the Joinpoint model. We predicted the future prevalence of AD from 2022 to 2030 using the Bayesian age-period-cohort model.

RESULTS

The total ASPR decreased slightly from 1990 (1357.93 per 100,000) to 2021 (1347.11 per 100,000). The ASPR of females (1457.64 per 100,000) was higher than that of males (1247.04 per 100,000) in 2021. The prevalence rate of AD was highest in the under 5 years old age group (3455.56 per 100,000) and the 5-9 years old age group (3360.31 per 100,000). By 2030, the predicted ASPR of AD will be 1394.36 (per 100,000) in males and 1603.69 in females (per 100,000). The predicted prevalence rate in the under 5 years old (3996.14 per 100,000 in males and 3990.68 per 100,000 in females) and 5-9 years old (3714.61 per 100,000 in males and 3963.96 per 100,000 in females) age groups will be higher than those in other age groups.

CONCLUSION

Despite a slight decrease from 1990 to 2021, there has been an increasing trend since 2015 in the total AD burden. Given the increasing burden of AD on Chinese children and females, healthcare practitioners should enhance community education, improve disease management abilities of patients and caregivers, and reduce the burden and healthcare costs of AD.

Management of Atopic Hand Dermatitis

Atopic hand dermatitis (AHD), a manifestation of atopic dermatitis, can have a profound negative effect on a patient's disease-related quality of life due to its visibility, chronic nature, and overall discomfort that it causes. AHD differs from other forms of chronic hand eczema due to its likely distinct, complex pathogenesis, which is a combination of environmental triggers, genetic predisposition, and immune dysfunction. A proper diagnosis of AHD is made through clinical evaluation and the ability to establish subtle clinical differences between AHD and other conditions. Diagnosis is the first step to a treatment plan that diverges from a one-size-fits-all approach.

Th Pathways in Immune-Mediated Skin Disorders: A Guide for Strategic Treatment Decisions

In recent years, there have been significant breakthroughs in the identification of immunological components of skin diseases and in the development of immunomodulatory drugs. Novel therapies create exciting prospects for personalized care. This article provides an overview of the role played by Th1, Th2, Th17, and follicular Th pathways in the most common skin diseases. Additionally, it elucidates the impact of current and upcoming treatments on each of these signaling cascades. Skin diseases predominantly influenced by a single dominant Th pathway such as psoriasis and atopic dermatitis are well-suited for biologics. However, in many other disorders a complex interplay between different immune pathways exists. This can lead to inconsistent efficacy of biologics based on individual patient profiles. In case of activation of several Th pathways, it may be more suitable to consider conventional therapies or JAK inhibitors. Increasing immunological insights have transitioned from laboratory research to practical applications, a trend that is expected to continue growing in the future.

Real-world efficacy of 2% crisaborole ointment on chronic hyperplasia lesions in 49 patients with atopic dermatitis

BACKGROUND

Crisaborole, as a phosphodiesterase 4 (PDE4) inhibitor (PDE4i), effectively inhibits inflammatory pathways, showing promising results in atopic dermatitis (AD), particularly in chronic hyperplasia lesions.

OBJECTIVES

Based on real-world data from China, this study assesses the effectiveness and safety of 2% PDE4i ointment as monotherapy for chronic hyperplastic AD lesions.

MATERIALS AND METHODS

A total of 49 AD patients aged 12 and above with chronic hyperplastic lesions and Investigator's Static Global Assessment scores of mild or moderate were enrolled. They received 2% PDE4i ointment twice daily until the lesions completely cleared. The effectiveness endpoints comprised the onset time of pruritus and lesion remission and the time of complete lesion clearance.

RESULTS

PDE4i demonstrated high effectiveness with minimal irritation, notable improvement in hyperpigmentation, and early remission of pruritus and lesions. The response varied across age groups; elderly patients experienced quicker pruritus relief compared to adolescents and adults, while adolescents showed earlier lesion remission by about 3 days. No significant difference was observed across age groups in the time for complete lesion clearance. Additionally, AD duration (less or more than 3 years) did not significantly impact pruritus or lesion remission.

CONCLUSIONS

PDE4i monotherapy is effective and safe for chronic hyperplasia lesions in AD across all age groups, and its effectiveness appears to be independent of AD duration.

Antibacterial and Antiallergic Effects of Three Tea Extracts on Histamine-Induced Dermatitis

Atopic dermatitis (AD) is a persistent and recurrent inflammatory skin condition with a genetic basis. However, the fundamental reasons and mechanisms behind this phenomenon remain incompletely understood. While tea extracts are known to reduce histamine-induced skin allergies and inflammation, the specific mechanisms by which various types of Chinese tea provide their protective effects are still not fully elucidated. In this study, a model of skin itching induced by histamine is used to explore the functions and mechanisms of three types of tea extract (Keemun black tea (HC), Hangzhou green tea (LC), and Fujian white tea (BC)) in alleviating histamine-induced dermatitis. The components of three tea extracts are identified by UPLC-Q-TOF-MS, and we found that their main components are alkaloids, fatty acyls, flavonoids, organic acids, and phenols. The inhibitory effects of three types of tea extract on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in skin injury are investigated by MIC and flow cytometry. The three types of tea extract have an inhibitory effect on the growth of bacterial flora, with HC showing the best inhibitory activity. The effect of the three types of tea extract on histamine-induced dermatitis is also evaluated. Furthermore, itchy skin experiments, HE staining, toluidine blue staining, and immunohistochemical staining of mouse skin tissues were performed to determine the variations of scratching, epidermal thickness, mast cell number, IL-1β, and NGF content after the administration of the tea extracts. The three types of tea extracts all alleviate and inhibit skin itching, epidermal hyperplasia, and allergic dermatitis. BC effectively alleviates epidermal hyperplasia caused by skin allergies, and LC significantly downregulates NGF. HC reduces histamine-induced mast cell infiltration and downregulates IL-1β to alleviate skin itching. Consequently, tea emerges a potent natural product that can inhibit the growth of skin wound bacterial flora and exhibit skin repair effects on histamine-induced allergic dermatitis.

Mapping the relationship between atopic dermatitis and gut microbiota: a bibliometric analysis, 2014-2023

Background

Atopic dermatitis (AD) is a chronic inflammatory skin condition affecting a significant portion of the population, with prevalence rates of 25% in children and 7-10% in adults. AD not only poses physical challenges but also profoundly impacts patients' mental well-being and quality of life. The stability of gut microbiota is crucial for overall health and can influence AD progression by modulating immune function, skin barrier integrity, and neuroendocrine signaling, which may be an effective target for the prevention and treatment of AD. Thus, exploring the interactions between AD and gut microbiota, particularly in infants, can provide insights into potential preventive and therapeutic strategies. This study aimed to explore the correlation between AD and gut microbiota while providing an overview of current research trends and emerging areas of interest in this field.

Methods

A comprehensive search was conducted on the Web of Science Core Collection (WOSCC) for relevant publications from January 1, 2014, to December 31, 2023. English-language articles and reviews were included. Two investigators independently screened the publications, and visual analysis was performed using CiteSpace, VOSviewer, Scimago Graphica, and Microsoft Excel software.

Results

A total of 804 articles were included, showing a significant increase in publications over the past decade. The United States, Wageningen University, and University Ulsan (represented by Hong SJ) had the highest number of published papers. Nutrients was the journal with the most publications, while the Journal of Allergy and Clinical Immunology had the highest number of citations and centrality among co-cited journals. Keyword visualization analysis identified "atopic dermatitis" and "gut microbiota" as central themes. Notably, there has been a notable shift in research focus over the years, with early studies concentrating on "Fecal microbiota," "caesarean section," and "first 6 months," while recent studies have highlighted the roles of "cells," "dysbiosis," and "prebiotics." This shift indicates growing interest in the underlying mechanisms and potential therapeutic interventions related to the intestinal microecology in AD treatment.

Conclusion

The field of AD and gut microbiota research has evolved significantly, with an increasing focus on understanding the intricate interactions between gut microbiota and AD pathogenesis. Recent years have witnessed increased interest in understanding the relationship between AD and gut microbiota, with researchers conducting extensive studies exploring various aspects of this connection. This review analyzes research trends over the past decade, highlighting trends and hotspots in the study of AD, particularly in infants, and the role of microbiota. This review serves as a valuable reference for future investigations, aiming to provide deeper insights into this burgeoning field and suggests directions for future research.

Targeting mitochondrial dysfunction in atopic dermatitis with trilinolein: A triacylglycerol from the medicinal plant Cannabis fructus

BACKGROUND

Atopic dermatitis (AD) is a common skin condition that causes chronic and recurring eczema lesions. Prior research has indicated that Cannabis fructus, the mature fruit of Cannabis sativa, has an antioxidant effect. Historically, Cannabis fructus has been used in cosmetics and medicine. However, there is limited knowledge regarding its biological components and the mechanisms by which it prevents and treats AD.

OBJECTIVES

HPLC-ESI-MS/MS analysis was utilized to identify the main compounds of Cannabis fructus, and trilinolein was extracted using chromatographic techniques. The potential of trilinolein in the prevention of AD was assessed, and its underlying mechanisms of action were elucidated.

METHODS

The distribution of distinct cellular subpopulations and the principal biological processes implicated in the pathogenesis of AD were assessed through a comparative study involving chronic AD patients and healthy controls (HCs). Differential gene expression was validated in clinical samples from the lesions of AD patients and the healthy skin of controls. The pharmacodynamic activity of trilinolein was validated in dinitrochlorobenzene (DNCB)-induced BALB/c mice and in IL-4- and TNF-α-induced HaCaT cells. Proteomics analyse was employed to investigate its mechanisms.

RESULTS

Single-cell transcriptome analysis revealed that chronic AD is characterized by abnormal keratinocyte differentiation and oxidative stress damage. When topically applied, trilinolein can effectively improve AD-like skin lesions induced by DNCB. It increases the expression of terminal differentiation proteins and decreases the expression of NADPH oxidase 2 (NOX2), with a therapeutic effect comparable to that of the positive control drug crisaborole. Additionally, trilinolein reduced ROS fluorescence intensity, restored mitochondrial morphology and membrane potential, and decreased mitochondrial DNA (mtDNA) release in keratinocytes stimulated with IL-4 and TNF-α. Moreover, trilinolein increased the protein expression of AhR, CYP1A1, and Nrf2 in a dose-dependent manner. The effect of trilinolein on keratinocyte terminal differentiation proteins and ROS levels was blocked by the addition of an AhR inhibitor.

CONCLUSION

The study suggests that trilinolein from Cannabis fructus alleviates NOX2-dependent mitochondrial dysfunction and repair the skin barrier via AhR-Nrf2 pathway, making it a promising agent for the prevention and treatment of AD.

The causal relationship between immune cells and atopic dermatitis: A bidirectional Mendelian randomization study

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin condition whose origins remain unclear. Existing epidemiological evidence suggests that inflammation and immune factors play pivotal roles in the onset and progression of AD. However, previous research on the connection between immune inflammation and AD has yielded inconclusive results.

METHODS

To evaluate the causal relationship between immunological characteristics and AD, this study employed a bidirectional, two-sample Mendelian randomization (MR) approach. We utilized large-scale, publicly available genome-wide association studies to investigate the causal associations between 731 immunological feature cells and the risk of AD.

RESULTS

Significant associations were identified between six immune phenotypes and AD risk: increased Basophil %CD33dim HLA DR-CD66b-, CD25 on IgD+ CD24+, CD40 on monocytes, HLA DR on CD14+ CD16-monocytes, HLA DR on CD14+monocytes correlated with higher AD risk, while elevated CD3 on CD4 Treg was linked to lower risk. Reverse MR analysis revealed AD as a risk factor for IgD+ CD38br AC and IgD+ CD38br %B cell, but a protective factor against CD20 on IgD+ CD38- naive and CD8 on NKT.

CONCLUSION

Our findings elucidate the intricate interplay between immune cells and AD, informing future research into AD pathophysiology and therapeutics.

Therapeutic Potential and Mechanisms of Mesenchymal Stem Cell and Mesenchymal Stem Cell-Derived Extracellular Vesicles in Atopic Dermatitis

Atopic dermatitis (AD) is a chronic and inflammatory skin disease with intense itchiness that is highly prevalent worldwide.The pathogenesis of AD is complex and closely related to genetic factors, immunopathogenic factors, environmental factors, and skin infections. Mesenchymal stem cells (MSCs) are non-hematopoietic progenitor cells derived from the mesenchymal stroma. They have anti-inflammatory, anti-apoptotic, and regenerative properties. Numerous studies demonstrate that MSCs can play a therapeutic role in AD by regulating various immune cells, maintaining immune homeostasis, and promoting the repair of damaged tissues. The key mediators for their biological functions are extracellular vesicles (MSC-Evs) and soluble cytokines derived from MSCs. The safety and efficacy of MSCs have been demonstrated in clinical Phase I / IIa trials for AD. This paper provides a comprehensive review of the pathogenesis of AD and the currently published studies on the function of MSCs and MSC-Evs in AD, primarily including the pathogenesis and the immunomodulatory impacts of MSCs and MSC-Evs, along with advancements in clinical studies. It provides insights for comprehending AD pathogenesis and investigating treatments based on MSCs.

Benvitimod upregulates filaggrin, involucrin and loricrin expressions via aryl hydrocarbon receptor-OVO-like 1 axis

Benvitimod has been successfully used in the treatment of psoriasis and atopic dermatitis (AD). However, the mechanism remains to be clarified. We aim to assess the effects of benvitimod on MC903-induced dermatitis in mice and to investigate the effects of benvitimod on filaggrin (FLG), involucrin (IVL), and loricrin (LOR) expressions and possible mechanism. MC903-induced mouse AD model was used to evaluate the effects of benvitimod. Filaggrin, involucrin, and loricrin protein and mRNA expressions in lesions of mice dermatitis were measured by Western blot and quantitative real-time PCR. In vitro, normal human epidermal keratinocytes (NHEKs) were cultured and benvitimod was used to treat NHEKs primed with IL-4 and IL-13. Then AHR and OVOL1 in NHEKs were knocked down to evaluate the role of AHR and OVOL1 in the effects of benvitimod. Topical treatment of benvitimod repaired skin barrier and alleviated skin inflammation in mouse AD model. This effect was inhibited by pretreatment with an AHR antagonist. Benvitimod upregulated the filaggrin, involucrin, and loricrin expressions in lesions of mouse AD model. In addition, benvitimod upregulated the filaggrin, involucrin, and loricrin expressions in NHEKs. Knockdown of AHR or OVO-like (OVOL)1 abrogated the upregulation of filaggrin, involucrin, and loricrin induced by benvitimod. Benvitimod attenuated MC903-induced mouse dermatitis and upregulated filaggrin, involucrin, and loricrin expressions via AHR-OVOL1 axis.

IL-22 in Atopic Dermatitis

Atopic dermatitis (AD) is a prevalent and chronic inflammatory skin condition characterized by a multifaceted pathophysiology that gives rise to diverse clinical manifestations. The management of AD remains challenging due to the suboptimal efficacy of existing treatment options. Nonetheless, recent progress in elucidating the underlying mechanisms of the disease has facilitated the identification of new potential therapeutic targets and promising drug candidates. In this review, we summarize the newest data, considering multiple connections between IL-22 and AD. The presence of circulating IL-22 has been found to correlate with the severity of AD and is identified as a critical factor driving the inflammatory response associated with the condition. Elevated levels of IL-22 in patients with AD are correlated with increased proliferation of keratinocytes, alterations in the skin microbiota, and impaired epidermal barrier function. Collectively, these factors contribute to the manifestation of the characteristic symptoms observed in AD.

Tralokinumab for the Treatment of Adult Atopic Dermatitis in Special Populations

Introduction

Even if mild forms of atopic dermatitis (AD) are usually well controlled with topical prescription drugs and emollients, the management of severe forms of the disease may be challenging, especially in special populations (SPs). These patients include groups of disadvantaged people (elderly, patients with disabilities and serious medical conditions) who are usually excluded from clinical trials. As a consequence, most of the data about the efficacy and safety of a drug in these patients derives from post-marketing experiences. In this context, the aim of our study was to retrospectively investigate the effectiveness and safety of tralokinumab in the management of AD in SPs.

Methods

A 24-weeks retrospective, dual-center study was performed enrolling patients with a diagnosis of moderate-to-severe AD undergoing treatment with tralokinumab at labelled dosage. Disease severity was assessed using Eczema Area Severity Index (EASI), Pruritus-Numerical Rating Scale (P-NRS), and Dermatology Life Quality Index (DLQI) score at baseline and after 4 weeks (W4), W16, and W24. Adverse events (AEs) were monitored at the same timepoints. Statistical significance of clinical improvement (EASI, P-NRS, DLQI) at week 4, week 16, and week 24 as compared with baseline was evaluated by using Student's t-test, considering significant a p-value <0.05.

Results

Our study enrolling 27 SPs patients showed a significant improvement in EASI and P-NRS since week 4, continuing to improve up to week 24. Similarly, DLQI significantly decreases at each timepoint as compared with baseline. Finally, no AEs were reported during the study period. Of interest, our cohort included oncologic patients, a patient with a history of severe infection, as well as subjects affected by severe neurological, psychiatric, pulmonary, and/or cardiovascular disease.

Discussion

Our experience showed that tralokinumab is effective and safe in elderly patients and subjects affected by severe comorbidities.

Exploring novel drug targets for atopic dermatitis through plasma proteome with genome

Atopic dermatitis (AD) is a chronic inflammatory disease with a complex and heterogeneous clinical presentation, leading to treatment limitations. Therefore, there is an urgent demand for new therapeutic drug targets. This study utilized Summary-data-based Mendelian randomization (SMR) to identify potential drug targets for AD. Summary statistics for 2,940 human plasma proteins were obtained from the UK Biobank, while AD statistics came from the Early Genetics and Epidemiology of Life Processes consortium and the FinnGen consortium. Furthermore, subsequent colocalization analyses confirmed the causal roles of candidate proteins. Moreover, Phenome-Wide Association Studies (PheWAS), protein-protein interaction (PPI), enrichment analysis, and single cell-type expression analysis provided additional insights. Additionally, drug prediction, druggability prediction, and molecular docking informed the discovery of novel drug targets. SMR analysis showed that eight plasma proteins were causally associated with AD: PVALB and TST were associated with a reduced risk of AD, while CA14, ECM1, IL22, IL6R, IL18R1, and MMP12 were associated with an increased risk of AD. Colocalization analysis confirmed significant associations for TST, IL22, and CA14. PheWAS further revealed that candidate drug targets were mainly linked to other allergic diseases. The corresponding protein-coding genes are predominantly expressed in melanocytes, T cells, and macrophages in skin tissue. Importantly, these proteins were identified to be involved in cytokine-cytokine receptor interaction, Th17 cell differentiation, and the JAK-STAT signaling pathway. All of these proteins are druggable, and six of them show great potential as drug targets. In conclusion, this study identified eight plasma proteins causally associated with AD and provided new insights into the etiology and potential drug targets for AD.

Metabolomic and lipidomic fingerprints in inflammatory skin diseases - Systemic illumination of atopic dermatitis, hidradenitis suppurativa and plaque psoriasis

Auto-inflammatory skin diseases place considerable symptomatic and emotional burden on the affected and put pressure on healthcare expenditures. Although most apparent symptoms manifest on the skin, the systemic inflammation merits a deeper analysis beyond the surface. We set out to identify systemic commonalities, as well as differences in the metabolome and lipidome when comparing between diseases and healthy controls. Lipidomic and metabolomic LC-MS profiling was applied, using plasma samples collected from patients suffering from atopic dermatitis, plaque-type psoriasis or hidradenitis suppurativa or healthy controls. Plasma profiles revealed a notable shift in the non-enzymatic anti-oxidant defense in all three inflammatory disorders, placing cysteine metabolism at the center of potential dysregulation. Lipid network enrichment additionally indicated the disease-specific provision of lipid mediators associated with key roles in inflammation signaling. These findings will help to disentangle the systemic components of autoimmune dermatological diseases, paving the way to individualized therapy and improved prognosis.

Genetic support for the causal association between 91 circulating inflammatory proteins and atopic dermatitis: A two-sample Mendelian randomization trial

BACKGROUND

Atopic dermatitis (AD) is a refractory disease that occurs in clinical practice. One of the most common inflammatory skin diseases, its occurrence and development are related to inflammation. Nevertheless, the precise nature of the relationship between circulating inflammatory proteins and AD remains uncertain.

METHODS

A two-sample MR analysis was performed to determine the causal relationship between the expression of 91 circulating inflammatory proteins and AD by using genome-wide association study (GWAS) summary statistics data from the FinnGen consortia. The robustness of the MR results was assessed by means of sensitivity analysis.

RESULTS

The causal relationship between the expression of nine specific circulating inflammatory proteins and AD was corroborated by the inverse variance weighted (IVW) method. The findings indicated that three circulating inflammatory proteins, namely, interleukin-18 receptor 1 [OR (CI) = 1.08 (1.05-1.11); p = 0.000001)], interleukin-8 [OR (CI) = 1.07 (1.00-1.14); p = 0.036244)], and tumor necrosis factor ligand superfamily member 14 [OR (CI) = 1.05 (1.00-1.10); p = 0.036842)], were positively correlated with AD. Additionally, six circulating inflammatory proteins were negatively correlated with AD: the T-cell surface glycoprotein CD5 [OR (CI) = 0.89 (0.84-0.95); p = 0.000191)], macrophage colony-stimulating factor 1 [OR (CI) = 0.93 (0.88-0.99); p = 0.031422)], fractalkine [OR (CI) = 0.91 (0.85-0.97); p = 0.003067)], interleukin-24 [OR (CI) = 0.91 (0.83-0.99); p = 0.031673)], signaling lymphocytic activation molecule [OR(CI) = 0.94 (0.89-1.00); p = 0.039818)], and urokinase-type plasminogen activator [OR(CI) = 0.95 (0.90-1.00); p = 0.037037)].

CONCLUSION

This study confirms the potential causal relationship between circulating inflammatory proteins and AD and provides guidance for the clinical diagnosis and treatment of AD.