Current Concepts of Psoriasis Immunopathogenesis

Decreased HMGCS1 inhibits proliferation and inflammatory response of keratinocytes and ameliorates imiquimod-induced psoriasis via the STAT3/IL-23 axis

Psoriasis is an immuno-inflammatory disease characterized by excessive keratinocyte proliferation, requiring extensive lipids. 3-hydroxy-3-methylglutaryl-coenzyme A synthase 1 (HMGCS1) is an essential enzyme in the mevalonate pathway, involved in cholesterol synthesis and the inflammatory response. However, the role of HMGCS1 in psoriasis has remained elusive. This study aims to elucidate the mechanism by which HMGCS1 controls psoriasiform inflammation. We discovered an increased abundance of HMGCS1 in psoriatic lesions when analyzing two Gene Expression Omnibus (GEO) datasets and confirmed this in psoriatic animal models and psoriatic patients by immunohistochemistry. In a TNF-α stimulated psoriatic HaCaT cell line, HMGCS1 was found to be overexpressed. Knockdown of HMGCS1 using siRNA suppressed the migration and proliferation of HaCaT cells. Mechanistically, HMGCS1 downregulation also reduced the expression of IL-23 and the STAT3 phosphorylation level. In imiquimod-induced psoriatic mice, intradermal injection of HMGCS1 siRNA significantly decreased the expression of HMGCS1 in the epidermis, which in turn led to an improvement in the Psoriasis Area and Severity Index score, epidermal thickening, and pathological Baker score. Additionally, expression levels of inflammatory cytokines IL-23, IL1-β, chemokine CXCL1, and innate immune mediator S100A7-9 were downregulated in the epidermis. In conclusion, HMGCS1 downregulation improved psoriasis in vitro and in vivo through the STAT3/IL-23 axis.

WTAP mediated m6A-modified circ_0056856 contributes to the proliferation, migration, and invasion of IL-22-stimulated human keratinocyte by miR-197-3p/CDK1 axis

BACKGROUND

Psoriasis is a chronic inflammation-associated skin disorder, and interleukin-22 (IL-22) is involved in psoriasis pathogenesis by boosting the proliferation and migration of keratinocytes. Mounting evidence has shown that circRNAs might play an important role in several aspects of psoriasis. This study is designed to explore the role and mechanism of circ_0056856 in regulating the phenotypes of IL-22-induced keratinocytes (HaCaT cells).

METHODS

Circ_0056856, microRNA-197-3p (miR-197-3p), Cyclin-dependent kinase 1 (CDK1), and Wilms tumor 1-associated protein (WTAP) levels were detected using real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability, proliferation, migration, and invasion were analyzed using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), 5-ethynyl-2'-deoxyuridine (EdU), Wound scratch, and Transwell assays. After being predicted by Circinteractome or TargetScan, binding between miR-197-3p and circ_0056856 or CDK1 was verified by a dual-luciferase reporter assay. CDK1 and WTAP protein levels were determined using Western blot. Interaction between WTAP and circ_0056856 was assessed using methylated RNA immunoprecipitation (MeRIP) assay.

RESULTS

Increased circ_0056856, CDK1, and WTAP were observed in psoriasis patients and IL-22-treated HaCaT cells. Moreover, circ_0056856 knockdown might repress IL-22-induced HaCaT cell proliferation, migration, and invasion in vitro. In mechanism, circ_0056856 might function as a sponge of miR-197-3p to modulate CDK1 expression, and WTAP improved circ_0056856 expression via m6A methylation.

CONCLUSION

WTAP-guided m6A modified circ_0056856 facilitates IL-22-stimulated HaCaT cell damage through the miR-197-3p/CDK1 axis, which could provide novel insights into psoriasis treatment.

MicroRNA-146a Signature in Psoriasis: A Systematic Review and Meta-Analysis

BACKGROUND

Psoriasis is a chronic, inflammatory, T-cell-mediated disease with a multifactorial pathogenesis. MicroRNA (miRNA) alteration in psoriasis has been identified within the last few years. In particular, miR-146a levels were altered. However, previous studies have equivocal or even contradictory findings.

OBJECTIVE

The current study aimed to perform a systematic review and meta-analysis to evaluate the miRNA expression profile in different tissues in patients with psoriasis. Further, the correlation between miR-146a levels and psoriasis severity as well as the specific expression patterns of the miR-146a profile in patients with psoriasis after treatment were evaluated.

METHODS

To retrieve studies investigating the correlation between miRNA and psoriasis, a comprehensive search of databases including PubMed, Cochrane Library, and Embase was performed from inception to 30 June 2023. Relevant journals and references of the included studies were also reviewed. A meta-analysis was conducted using the comprehensive meta-analysis version 3.

RESULTS

The correlation between the miR-146a expression levels and psoriasis susceptibility in 14 studies was assessed. Results showed that the miR-146a expression level was upregulated in psoriasis samples [P = 0.001, standardized mean difference (SMD) = 1.489, 95% confidence interval (CI) = 0.618-2.360]. In a subgroup analysis based on sample type, the correlation between the peripheral blood mononuclear cell, blood, and tissue miR-146a expression level and psoriasis was significant (SMD = 1.293, 95% CI 0.310-2.276, P = 0.01; SMD = 2.526, 95% CI 1.710-3.342, P = 0.000; SMD = 3.153, 95% CI 1.432-4.874, P = 0.00, respectively). A positive correlation was observed between the miR-146a expression levels and Psoriasis Area and Severity Index (PASI) score. However, the result was not statistically significant (correlation coefficient = 0.29, 95% CI - 0.038 to 0.575, P = 0.081). Further, the miR-146a levels decreased after treatment (SMD = - 1.592, 95% CI - 2.067 to - 1.117, P = 0.000, I2 = 74.104).

CONCLUSIONS

The miR-146a expression level is positively correlated with and can contribute to the pathobiology of psoriasis.

Metabolic dysfunction associated steatotic liver disease in patients with plaque psoriasis: a case-control study and serological comparison

Background

The relationship between plaque psoriasis and both MASLD and lean MASLD has not been sufficiently explored in the current literature.

Method

This retrospective and observational study was carried out from January 2021 to January 2023 at The First Affiliated Hospital of Zhejiang Chinese Medical University. Patients diagnosed with plaque psoriasis and a control group consisting of individuals undergoing routine physical examinations were enrolled. The incidence of MASLD and lean MASLD among these groups was compared. Additionally, patients with plaque psoriasis were divided into those with MASLD, those with lean MASLD, and a control group with only psoriasis for a serological comparative analysis.

Results

The incidence of MASLD in the observation group and the control group was 43.67% (69/158) and 22.15% (35/158), respectively (p < 0.01). Furthermore, the incidence of lean MASLD within the observation group and the control group was 10.76% (17/158) and 4.43% (7/158), respectively (p < 0.01). After controlling for potential confounding variables, plaque psoriasis was identified as an independent risk factor for MASLD with an odds ratio of 1.88 (95% cl: 1.10-3.21). In terms of serological comparison, compared to the simple psoriasis group, we observed a significant elevation in the tumor marker CYFRA21-1 levels in both groups compared to the control group with simple psoriasis (p < 0.01). Moreover, the MASLD group exhibited elevated levels of inflammatory markers and psoriasis score, whereas these effects were mitigated in the lean MASLD group.

Conclusion

The prevalence of MASLD and lean MASLD is higher among patients with psoriasis. Those suffering from psoriasis along with MASLD show increased psoriasis scores and inflammatory markers compared to those without metabolic disorders. MASLD likely worsens psoriasis conditions, indicating the necessity of targeted health education for affected individuals to reduce the risk of MASLD, this education should include guidelines on exercise and diet. In serological assessments, elevated levels of cytokeratin 19 fragment (CYFRA21-1) were noted in both MASLD and lean MASLD groups, implying a potential synergistic role between psoriasis and MASLD.

Single-cell technologies in psoriasis

Psoriasis is a chronic and recurrent inflammatory skin disorder. The primary manifestation of psoriasis arises from disturbances in the cutaneous immune microenvironment, but the specific functions of the cellular components within this microenvironment remain unknown. Recent advancements in single-cell technologies have enabled the detection of multi-omics at the level of individual cells, including single-cell transcriptome, proteome, and metabolome, which have been successfully applied in studying autoimmune diseases, and other pathologies. These techniques allow the identification of heterogeneous cell clusters and their varying contributions to disease development. Considering the immunological traits of psoriasis, an in-depth exploration of immune cells and their interactions with cutaneous parenchymal cells can markedly advance our comprehension of the mechanisms underlying the onset and recurrence of psoriasis. In this comprehensive review, we present an overview of recent applications of single-cell technologies in psoriasis, aiming to improve our understanding of the underlying mechanisms of this disorder.

Mass Spectrometry-Based Proteomics Analysis Unveils PTPRS Inhibits Proliferation and Inflammatory Response of Keratinocytes in Psoriasis

In this study, we used data-independent acquisition-mass spectrometry (DIA-MS) to analyze the serum proteome in psoriasis vulgaris (PsO). The serum proteomes of seven healthy controls and eight patients with PsO were analyzed using DIA-MS. Weighted gene co-expression network analysis was used to identify differentially expressed proteins (DEPs) that were closely related to PsO. Hub proteins of PsO were also identified. The Proteomics Drug Atlas 2023 was used to predict candidate hub protein drugs. To confirm the expression of the candidate factor, protein tyrosine phosphatase receptor S (PTPRS), in psoriatic lesions and the psoriatic keratinocyte model, immunohistochemical staining, quantitative real-time polymerase chain reaction, and western blotting were performed. A total of 129 DEPs were found to be closely related to PsO. The hub proteins for PsO were PVRL1, FGFR1, PTPRS, CDH2, CDH1, MCAM, and THY1. Five candidate hub protein drugs were identified: encorafenib, leupeptin, fedratinib, UNC 0631, and SCH 530348. PTPRS was identified as a common pharmacological target for these five drugs. PTPRS knockdown in keratinocytes promoted the proliferation and expression of IL-1α, IL-1β, IL-23A, TNF-α, MMP9, CXCL8, and S100A9. PTPRS expression was decreased in PsO, and PTPRS negatively regulated PsO. PTPRS may be involved in PsO pathogenesis through the inhibition of keratinocyte proliferation and inflammatory responses and is a potential treatment target for PsO.

Serum levels of tumour necrosis factor (TNF-α) and interleukin-17 (IL-17) in patients with nail psoriasis: A cross-sectional study

Background Psoriasis is a common chronic inflammatory disorder affecting all aspects of a patient's life. Nail involvement is frequent, but little is known about its associated inflammatory biomarker profile, including similarities or differences from cutaneous disease. Aims We conducted this cross-sectional study to evaluate serum levels of inflammatory cytokines [tumour necrosis factor-alpha (TNF-α) and interleukin -17 (IL-17)] in patients with nail psoriasis and compared these to psoriasis patients without nail involvement, as well as in non-psoriatic healthy controls. Methods Adult psoriasis patients with (Group I, n = 30) and without nail involvement (Group-II, n = 30) were sequentially recruited. In addition, non-psoriatic healthy controls (Group-III, n = 20) were recruited. The nail disease severity by NAPSI score was determined for patients in Group I. Cutaneous disease severity (by PASI score) and presence of psoriatic arthritis (through CASPAR criteria) were evaluated for patients in Groups I and II. Serum levels of TNF-α, IL-17, erythrocyte sedimentation rate (ESR), rheumatoid factor (RA factor), and anti-cyclic citrullinated peptide antibody (Anti-CCP) were evaluated for all three groups. Results The median age was significantly higher for Group I as compared to Group II patients (41 ± 12.6 years vs 30 ± 12.4 years, p = 0.017). Group I patients also had higher median PASI score than Group II patients, although the difference was not statistically significant (10 ± 11.41 vs 6.50 ± 5.46, p = 0.275). The mean serum IL-17 levels were significantly higher for Group-I (113.39 ± 251.30 pg/mL) than Group II (27.91 ± 18.22 pg/mL, p = 0.002) and Group III (25.67 ± 12.08 pg/mL, p = 0.005). A weak positive correlation was found between NAPSI and serum IL-17 levels (Spearman's Rho = 0.355) though not statistically significant (p = 0.054). Correlation between serum IL-17 and PASI was poor for Group-I patients (Spearman's Rho = 0.13, p = 0.944) and strongly negative for Group-II patients (Spearman's Rho = -0.368, statistically significant with p = 0.045). The mean serum levels of TNF-α were below the detection threshold of the assay kit, hence no meaningful comparison could be made. Limitations A small sample size and low sensitivity of TNF-α assay kit. Conclusion Our study showed that nail psoriasis could be independently associated with an elevation of IL-17. This can help choose appropriate drugs and estimate drug response in patients with nail psoriasis.

Functional Genomics and Insights into the Pathogenesis and Treatment of Psoriasis

Psoriasis is a lifelong, systemic, immune mediated inflammatory skin condition, affecting 1-3% of the world's population, with an impact on quality of life similar to diseases like cancer or diabetes. Genetics are the single largest risk factor in psoriasis, with Genome-Wide Association (GWAS) studies showing that many psoriasis risk genes lie along the IL-23/Th17 axis. Potential psoriasis risk genes determined through GWAS can be annotated and characterised using functional genomics, allowing the identification of novel drug targets and the repurposing of existing drugs. This review is focused on the IL-23/Th17 axis, providing an insight into key cell types, cytokines, and intracellular signaling pathways involved. This includes examination of currently available biological treatments, time to relapse post drug withdrawal, and rates of primary/secondary drug failure, showing the need for greater understanding of the underlying genetic mechanisms of psoriasis and how they can impact treatment. This could allow for patient stratification towards the treatment most likely to reduce the burden of disease for the longest period possible.

Effect of stearyl alcohol on imiquimod-induced psoriasis-like skin inflammation in mice

Psoriasis is a chronic inflammatory skin disease. Topical medicines are the preferred treatment for mild to moderate psoriasis, but the effect of excipients used in semi-solid preparations on psoriasis-like skin inflammation is not fully understood. In the present study, we investigated the effect of stearyl alcohol, a commonly used excipient, on imiquimod (IMQ)-induced psoriasis-like skin inflammation in mice. Psoriasis-like skin inflammation was induced by topical IMQ treatment on the back of mice. Skin lesion severity was evaluated by using psoriasis area and severity index (PASI) scores. The skin sections were stained by haematoxylin-eosin and immunohistochemistry. Stearyl alcohol (20% in vaseline) treatment significantly reduced the IMQ-induced increase of PASI scores and epidermal thickness in mice. IMQ treatment increased the number of Ki67- and proliferating cell nuclear antigen (PCNA)-positive cells in the skin, and the increases were inhibited by stearyl alcohol (20% in vaseline) treatment. Stearyl alcohol treatment (1%, 5%, 10% in vaseline) dose-dependently ameliorated IMQ-induced increase of PASI scores and epidermal thickness in mice. Hexadecanol (20% in vaseline), stearic acid (20% in vaseline) and vaseline treatment had no significant effect on IMQ-induced psoriasis-like skin inflammation in mice. In conclusion, stearyl alcohol has the effect of improving IMQ-induced psoriasis-like skin inflammation in mice.

Rutaecarpine ameliorates imiquimod-induced psoriasis-like dermatitis in mice associated with alterations in the gut microbiota

Psoriasis is accepted as a chronic, inflammatory, immune-mediated skin disease triggered by complex environmental and genetic factors. For a long time, disease recurrence, drug rejection, and high treatment costs have remained enormous challenges and burdens to patients and clinicians. Natural products with effective immunomodulatory and anti-inflammatory activities from medicinal plants have the potential to combat psoriasis and complications. Herein, an imiquimod (IMQ)-induced psoriasis-like dermatitis model is established in mice. The model mice are treated with 1% rutaecarpine (RUT) (external use) or the oral administration of RUT at different concentrations. Furthermore, high-throughput 16S rRNA gene sequencing is applied to analyze the changes in the diversity and composition of the gut microbiota. Based on the observation of mouse dorsal skin changes, RUT can protect against inflammation to improve psoriasis-like skin damage in mice. Additionally, RUT could suppress the expression levels of proinflammatory cytokines (IL-23, IL-17A, IL-22, IL-6, and IFN-α) within skin tissue samples. Concerning gut microbiota, we find obvious variations within the composition of gut microflora between IMQ-induced psoriasis mice and RUT-treated psoriasis mice. RUT effectively mediates the recovery of gut microbiota in mice induced by IMQ application. Psoriasis is linked to the production of several inflammatory cytokines and gut microbiome alterations. This research shows that RUT might restore gut microbiota homeostasis, reduce inflammatory cytokine production, and ameliorate psoriasis symptoms. In conclusion, the gut microbiota might be a therapeutic target or biomarker for psoriasis that aids in clinical diagnosis and therapy.

miR-26a-5p inhibits the proliferation of psoriasis-like keratinocytes in vitro and in vivo by dual interference with the CDC6/CCNE1 axis

Psoriasis is a chronic inflammatory proliferative dermatological ailment that currently lacks a definitive cure. Employing data mining techniques, this study identified a collection of substantially downregulated miRNAs (top 10). Notably, 32 targets were implicated in both the activation of the IL-17 signaling pathway and cell cycle dysregulation. In silico analysis revealed that one of these miRNAs, miR-26a-5p, is a highly conserved cross-species miRNA. Strikingly, the miR-26a-5p sequences in humans and mice are identical, and mmu-miR-26a-5p was found to target the same 7 cell cycle targets as its human counterpart, hsa-miR-26a-5p. Among these targets, CDC6 and CCNE1 were the most effective targets of miR-26a-5p, which was further validated in vitro using a dual luciferase reporter system and qPCR assay. The therapeutic assessment of miR-26a-5p revealed its remarkable efficacy in inhibiting the proliferation and G1/S transition of keratinocytes (HaCaT and HEKs) in vitro. In vivo experiments corroborated these findings, demonstrating that miR-26a-5p effectively suppressed imiquimod (IMQ)-induced psoriasis-like skin lesions in mice over an 8-day treatment period. Histological analysis via H&E staining revealed that miR-26a-5p treatment resulted in reduced keratinocyte thickness and immune cell infiltration into the spleens of IMQ-treated mice. Mechanistic investigations revealed that miR-26a-5p induced a cascade of downregulated genes associated with the IL-23/IL-17A axis, which is known to be critical in psoriasis pathogenesis, while concomitantly suppressing CDC6 and CCNE1 expression. These findings were corroborated by qPCR and Western blot analyses. Collectively, our study provides compelling evidence supporting the therapeutic potential of miR-26a-5p as a safe and reliable endogenous small nucleic acid for the treatment of psoriasis.

Therapeutic potential of adipose derived stromal cells for major skin inflammatory diseases

Inflammatory skin diseases like psoriasis and atopic dermatitis are chronic inflammatory skin conditions continuously under investigation due to increased prevalence and lack of cure. Moreover, long-term treatments available are often associated with adverse effects and drug resistance. Consequently, there is a clear unmet need for new therapeutic approaches. One promising and cutting-edge treatment option is the use of adipose-derived mesenchymal stromal cells (AD-MSCs) due to its immunomodulatory and anti-inflammatory properties. Therefore, this mini review aims to highlight why adipose-derived mesenchymal stromal cells are a potential new treatment for these diseases by summarizing the pre-clinical and clinical studies investigated up to date and addressing current limitations and unresolved clinical questions from a dermatological and immunomodulatory point of view.

SPRR1B is Related to the Immune Microenvironment and Can Be Used as a Biomarker for the Diagnosis of Psoriasis

Background

Psoriasis, a chronic inflammatory disorder with an unknown cause, significantly impacts the physical and psychological well-being of patients. However, current biomarkers related to psoriasis lack clinical specificity, sensitivity, and predictive ability.

Methods

In this study, we collected skin lesion tissues from 20 psoriasis patients and 20 normal skin samples. Additionally, we obtained four datasets from the GEO database, which included human psoriasis and healthy specimens. We utilized SVM-RFE analysis and the LASSO regression model to identify potential biomarkers. Furthermore, we examined the composition of immune cell types in psoriasis and their correlation with specific genes.

Results

Our investigation revealed 57 differentially expressed genes (DEGs), and we identified significantly enriched pathways through KEGG pathway analysis. The results of machine learning and WGCNA suggested that LCE3D and SPRR1B could potentially be used as marker genes for diagnosing psoriasis. RT-PCR and immunohistochemical detection confirmed the abnormally high expression of the SPRR1B gene in psoriasis. Analysis of immune cell infiltration revealed a strong positive correlation between SPRR1B and Macrophages M0 and T cells follicular helper, while showing the strongest negative correlation with resting Mast cells. In addition, we found that silencing SPRR1B in IFN-γ-treated HaCat cells could significantly reduce the increase in IL-17, IL-22, KRT6, and KRT16 caused by IFN-γ.

Conclusion

These findings suggest that SPRR1B may have a significant role in the pathogenesis of psoriasis and could be employed as a novel immunomarker for its development.

HMGB1 regulates Th17 cell differentiation and function in patients with psoriasis

BACKGROUND

Psoriasis is an immune-mediated chronic inflammatory skin disease, in which T helper 17 (Th17) cells and its effective cytokine interleukin (IL)-17A play a pivotal pathogenic role. High mobility group box 1 (HMGB1) is an important proinflammatory cytokine, which has been confirmed to be highly expressed in the peripheral circulation and epidermis tissues of psoriasis patients. The regulatory effect of HMGB1 on IL-17A expression and function has been reported in some inflammatory and autoimmune diseases by the HMGB1-Toll-like receptor 4 (TLR4)-interleukin (IL)-23-IL-17A pathway. While, in the pathological environment of psoriasis, whether HMGB1 can exert the regulatory effect on IL-17A is not clear.

OBJECTIVE

We aimed to evaluate the role of HMGB1-TLR4-IL-23-IL-17A pathway in the pathogenesis of psoriasis and explore the possible regulatory mechanism of HMGB1 on Th17 cell differentiation.

METHODS

Serum levels of HMGB1, TLR4, IL-23, and IL-17A were quantified in 50 patients with moderate-to-severe plaque psoriasis and 30 healthy controls. Peripheral blood mononuclear cells  were acquired from 10 severe psoriasis patients and administrated by different concentrations of recombinant-HMGB1 (rHMGB1) to detect the Th17 cell percentage, mRNA and protein levels of TLR4, IL-23, IL-17A and retinoid-related orphan receptor γt (RORγt).

RESULTS

The serum levels of HMGB1, TLR4, IL-23, and IL-17A in psoriasis patients were significantly higher than healthy controls, especially in severe patients, and positively correlated with the severity index. There were also positive correlations between every two detected indicators of HMGB1, TLR4, IL-23, and IL-17A. In vitro study, rHMGB1 can promote the elevated expression of Th17 cell percentage as well as TLR4, IL-23, IL-17A, and RORγt in a dose-dependent manner.

CONCLUSION

HMGB1 can contribute to the pathogenesis of psoriasis by regulating Th17 cell differentiation through HMGB1-TLR4-IL-23-RORγt pathway, then promotes IL-17A production and aggravates inflammation process. Targeting HMGB1 may be a possible potential candidate for the immunotherapy of psoriasis.

Anti-psoriasis molecular targets and active components discovery of Optimized Yinxieling Formula via affinity-purified strategy

Psoriasis, a prevalent inherited skin condition, involves an inflammatory response as a key pathogenic mechanism. The Optimized Yinxieling Formula (OYF), rooted in traditional Chinese medicine, is extensively utilized in clinical settings to treat psoriasis. Although previous studies have demonstrated OYF's significant anti-inflammatory effects in psoriasis, its potential molecular targets and active components remain unexplored. This study aimed to unveil the anti-psoriasis molecular targets and active components of OYF. Our findings indicated that OYF extract markedly reduced the production of several inflammatory mediators, including IL-23, nitric oxide, TNF-α, and IL-1β, in LPS-induced RAW264.7 cells. We synthesized OYF extract-crosslinked beads to isolate pharmacological targets from RAW264.7 lysates using an affinity purification strategy, known as Target Fishing. The enriched target proteins were subsequently identified via LC-MS/MS, followed by bioinformatics analysis to map the psoriasis-associated pathway-gene network. We identified a total of 76 potential target proteins, which were highly associated with mRNA transcription mechanisms. In particular, pathway-gene network analysis revealed that the IL-23 inflammatory pathway was involved in the anti-psoriasis effect of OYF extract. We further utilized a target protein-based affinity capture strategy, combined with LC-MS and SPR analysis, to globally screen OYF's active components, focusing on the mRNA transcription regulator, fused in sarcoma (FUS). This process led to the identification of umbelliferone, vanillic acid, protocatechuic acid, gentisic acid, and echinacoside as key compounds targeting FUS to inhibit IL-23 expression. Additionally, we formulated a compound cocktail (CpdC), which significantly reduced psoriasis area and severity index (PASI) scores and the expressions of IL-23 and Ki67 in an imiquimod (IMQ)-induced psoriasis mouse model. Collectively, our study elucidates the primary molecular targets and active components of OYF, offering novel insights for psoriasis treatment.

Severe Xerostomia Induced by Multiple Systemic Diseases in a Patient with Psoriasis Vulgaris: A Case Report and Literature Review

Introduction

Psoriasis is a complex autoimmune disease associated with chronic systemic keratinization and inflammation, which can affect the skin, joints, and oral cavity. Xerostomia is a subjective feeling of oral dryness that impairs patient comfort and lowers the quality of life. The aim of this case report is to describe the clinical mechanism of xerostomia in a psoriasis patient with multiple systemic diseases.

Case Report

A 51-year-old inpatient man with psoriasis vulgaris was referred to the Oral Medicine Department with complaints of difficulty swallowing due to a sore throat and dry tongue since last week. The patient had psoriasis vulgaris 15 years ago, chronic adrenal insufficiency, psoriatic arthritis, acute circulatory collapse, anemia of inflammation, acute kidney injury, dehydration, gastritis, urinary tract infections, and malnutrition. A complete anamnesis and oral examination were done. The patient was diagnosed with severe xerostomia, a fissured tongue, exfoliative cheilitis, angular cheilitis, and gingivitis by the Oral Medicine Department.

Case Management

The patient was treated with petroleum jelly, chlorine dioxide mouthwash, miconazole cream, and benzydamine HCl lozenges.

Conclusion

Based on case reports and reviews, multiple systemic diseases may not only increase the risk of xerostomia but also aggravate its severity.

Gallic Acid Alleviates Psoriasis Keratinization and Inflammation by Regulating BRD4 Expression

Psoriasis is a chronic non-contagious autoimmune disease. Gallic acid is a natural compound with potential health benefits, including antioxidant, anticancer, antiviral and antibacterial properties. Nevertheless, the influence of gallic acid on psoriasis has not been fully determined. This investigation aimed to discover the effect of gallic acid on psoriasis. Thirty-one pairs of psoriatic skin tissues and healthy adult human skin tissues were collected. Human keratinocytes (HaCaT cells) were transfected with interleukin 17A (IL-17A) to create the psoriatic keratinocyte model. The content of bromodomain-containing protein 4 (BRD4) microRNA was assessed using qRT-PCR testing. The content of BRD4 was detected by Western blotting. Cell migration was evaluated by conducting a wound healing assay. Cell proliferation was determined using an EdU assay. Apoptosis was detected by the TUNEL assay. The contents of interferon gamma (IFN-γ), IL-6, IL-8 and IL-17 were detected by ELISA. BRD4 was up-regulated in psoriatic skin tissues and in the IL-17A group compared to the healthy adult human skin tissues and the control group. Silencing BRD4 inhibited cell migration, proliferation and inflammatory response but induced apoptosis in IL-17A-treated HaCaT cells. Conversely, BRD4 over-expression promoted cell migration, proliferation and inflammatory response but suppressed apoptosis in IL-17A-treated HaCaT cells. Gallic acid repressed cell migration, proliferation and inflammatory response but indu-ced apoptosis in HaCaT cells transfected with IL-17A by down-regulating BRD4. Gallic acid represses cell migration, proliferation and inflammatory response but induces apoptosis in IL-17A-transfected HaCaT cells by down-regulating BRD4.

Signaling pathways and targeted therapies for psoriasis

Psoriasis is a common, chronic, and inflammatory skin disease with a high burden on individuals, health systems, and society worldwide. With the immunological pathologies and pathogenesis of psoriasis becoming gradually revealed, the therapeutic approaches for this disease have gained revolutionary progress. Nevertheless, the mechanisms of less common forms of psoriasis remain elusive. Furthermore, severe adverse effects and the recurrence of disease upon treatment cessation should be noted and addressed during the treatment, which, however, has been rarely explored with the integration of preliminary findings. Therefore, it is crucial to have a comprehensive understanding of the mechanisms behind psoriasis pathogenesis, which might offer new insights for research and lead to more substantive progress in therapeutic approaches and expand clinical options for psoriasis treatment. In this review, we looked to briefly introduce the epidemiology, clinical subtypes, pathophysiology, and comorbidities of psoriasis and systematically discuss the signaling pathways involving extracellular cytokines and intracellular transmission, as well as the cross-talk between them. In the discussion, we also paid more attention to the potential metabolic and epigenetic mechanisms of psoriasis and the molecular mechanistic cascades related to its comorbidities. This review also outlined current treatment for psoriasis, especially targeted therapies and novel therapeutic strategies, as well as the potential mechanism of disease recurrence.

Comprehensive Analysis to Identify Rh Family C Glycoprotein (RHCG) as the Causative Gene for Psoriasis and Search for Alternative Treatment Modalities

Background

Psoriasis is a complex autoimmune disease. Frequent interactions between epidermal and immune cells are likely to be responsible for the strong heterogeneity of psoriasis. Therefore, our work aims to build on current knowledge and further search for new molecular mechanisms related to psoriasis pathogenesis in order to develop new targeted drugs.

Methods

Data from psoriasis samples were obtained from the Gene Expression Omnibus (GEO) database, and batch effects were corrected using the "Combat" algorithm in the "SVA" package. Functional annotation of differential genes in psoriasis was performed by Gene set enrichment analysis (GSEA). Core functional modules were identified using the Multiscale Embedded Gene Co-Expression Network Analysis (MEGENA) algorithm for selection from the differential gene interaction network. The expression and potential function of Rh Family C Glycoprotein (RHCG) was predicted in single cell data by the "Seurat" package and validated in psoriasis samples by multiplex immunofluorescence. In addition, the regulatory function of HOP Homeobox (HOPX) on RHCG in keratinocytes was confirmed using RNA interference. Using immune infiltration analysis, RHCG and DC cells were analyzed for their association. Finally, the molecular mechanisms of treatment of psoriasis using Tripterygii Radix (TR) and Cinnamomi Ramulus (CR) were explored through network pharmacology and experimental validation.

Results

Immune response (represented by C1_2) and collagen matrix formation (represented by C1_3) were identified as two important pathogenic factors in psoriasis and helped to define new biological subtypes of psoriasis. One important psoriasis hub gene, RHCG, was obtained and found to be closely associated with keratinocyte differentiation as well as DC cell maturation. And RHCG was regulated by HOPX in keratinocytes. In addition, the mechanism of action of CR and TR in the treatment of psoriasis was tentatively confirmed to be related to TRPV3, NFKB2, and YAP1.

Conclusions

Our study identifies a new causal disease gene (RHCG) and offers potential alternatives for the treatment of psoriasis.

Meta-analysis and GRADE assessment of randomized controlled trials on the efficacy and safety of bimekizumab in psoriatic arthritis patients

OBJECTIVE

A persistent immune-mediated inflammatory disorder called psoriatic arthritis affects about 25% of persons with psoriasis. Bimekizumab, a humanized monoclonal IgG1 antibody, is a novel therapeutic approach that inhibits homodimers and heterodimers of IL-17A and IL-17F by binding to comparable locations in these molecules. Bimekizumab was the subject of a meta-analysis to assess its efficacy and safety in psoriatic arthritis patients.

METHODS

All randomized clinical trials were looked up on PubMed, Scopus, and Web of Science. The Systematic Review Accelerator tool was used to screen them, and RevMan was used to analyze them. The Mean Difference (MD) and 95% Confidence Interval (CI) were used to examine continuous data, whereas the Risk Ratio (RR) and 95% CI were used to evaluate dichotomous data.

RESULTS

A total of 1364 participants from 4 trials were included in this meta-analysis. The number of participants who met the American College of Rheumatology 50 threshold was significantly higher in the bimekizumab group compared to the placebo group [RR = 4.94, 95% CI (3.73, 6.55), p < .00001]. Psoriasis Area and Severity Index 100 was achieved by significantly more people in the bimekizumab group than in the placebo group [RR = 11.45, 95% CI (6.67, 19.67), p < .00001]. There was no significant difference between the bimekizumab group and the placebo group in terms of treatment-emergent adverse events [RR = 1.08, 95% CI (0.97, 1.21), p = .15].

CONCLUSION

In comparison to a placebo, bimekizumab treatment significantly improved joint and skin efficacy outcomes. Also, its safety results were acceptable.

Statistically Optimized Tacrolimus and Thymoquinone Co-Loaded Nanostructured Lipid Carriers Gel for Improved Topical Treatment of Psoriasis

The aim of this investigation was to develop and analyze a tacrolimus and thymoquinone co-loaded nanostructured lipid carriers (TAC-THQ-NLCs)-based nanogel as a new combinatorial approach for the treatment of psoriasis. The NLCs were formulated by an emulsification-solvent-evaporation technique using glyceryl monostearate, Capryol 90 (oil), and a mixture of Tween 80 and Span 20 as a solid lipid, liquid lipid, and surfactant, respectively. Their combination was optimized using a three-factor and three-level Box-Behnken design (3³-BBD). The optimized TAC-THQ-NLCs were observed to be smooth and spherical with a particle size of 144.95 ± 2.80 nm, a polydispersity index of 0.160 ± 0.021, a zeta potential of -29.47 ± 1.9 mV, and an entrapment efficiency of >70% for both drugs. DSC and PXRD studies demonstrated the amorphous state of TAC and THQ in the lipid matrix of the NLCs. An FTIR analysis demonstrated the excellent compatibility of the drugs with the excipients without interactions. The TAC-THQ-NLC-based nanogel (abbreviated as TAC-THQ-NG) exhibited a good texture profile and good spreadability. The in vitro release study demonstrated a sustained drug release for 24 h from the TAC-THQ-NG that followed the Korsmeyer-Peppas kinetic model with a Fickian diffusion mechanism. Moreover, the TAC-THQ-NG revealed significantly higher dose-dependent toxicity against an HaCaT cell line compared to a TAC-THQ suspension gel (abbreviated as TAC-THQ-SG). Furthermore, the developed formulations demonstrated antioxidant activity comparable to free THQ. Confocal microscopy revealed improved permeation depth of the dye-loaded nanogel in the skin compared to the suspension gel. Based on these findings, it was concluded that TAC-THQ-NG is a promising combinatorial treatment approach for psoriasis.

Association between IL-17F, IL-17RA Gene Polymorphisms and Response to Biological Drugs in Psoriasis and Beyond

Psoriasis is a systemic inflammatory disease that associates with multiple comorbidities. It involves complex interactions between environmental factors and polygenic predisposition. The IL-17 family is one of the main actors in the pathogenesis of psoriasis. Secondary nonresponse is common, especially during the long-term use of TNF-α inhibitors, but it is not uncommon even for newer biologics, such as IL-17 inhibitors. Identification of clinically useful biomarkers of treatment efficacy and safety would enable optimal treatment selection, improve patient quality of life and outcome, and reduce healthcare costs. To our knowledge, this is the first study to evaluate the relationship between genetic polymorphism of IL-17F (rs763780) and IL-17RA (rs4819554) and response to biological treatment and other clinical data in bio-naive and secondary non-responders psoriasis patients in Romania and Southeastern Europe. We performed a prospective, longitudinal, analytical cohort study of 81 patients diagnosed with moderate-to-severe chronic plaque psoriasis who received biological treatments for the first time. Of the 79 patients treated with TNF-α inhibitors, 44 experienced secondary nonresponse. All patients were genotyped for the two SNPs in IL-17F and IL-17RA genes. The rs763780 polymorphism in the IL-17F gene could be an attractive candidate biomarker for predicting which patients will respond to anti-TNF-α therapies. Another emergent association of rs4819554 in IL-17RA with the risk of nail psoriasis and a higher BMI in moderate-to-severe plaque psoriasis patients is described.

Macrophages mediate psoriasis via Mincle-dependent mechanism in mice

Psoriasis is currently considered to be an immune and inflammatory disease characterized by massive immune cells infiltration including macrophages. It has been reported that macrophage-inducible C-type lectin (Mincle) is essential to maintain the pro-inflammatory phenotype of M1 macrophages, however, its role and mechanisms in psoriasis remain largely unknown. A model of psoriasis was induced in mice by a daily topical application of imiquimod for 7 days. Role and mechanisms of Mincle in macrophage-mediated psoriasis were investigated in clodronate liposomes induced macrophage depletion mice followed by adoptively transferring with Mincle-expressing or -knockout (KO) macrophages, and in macrophage specific Mincle knockout mice (Mincle^loxp/loxp/Lyz2-cre^+/+). Finally, a Mincle neutralizing antibody was employed to the psoriasis mice to reveal the therapeutic potential for psoriasis by targeting Mincle. Mincle was highly expressed by M1 macrophages in the skin lesions of patients and mice with psoriasis. Clodronate liposomes-induced macrophage depletion inhibited psoriasis in mice, which was restored by adoptive transfer with Mincle-expressing macrophages but not by Mincle-KO macrophages. This was further confirmed in macrophage-specific Mincle-KO mice. Mechanistically, macrophages mediated psoriasis via the Mincle-Syk-NF-κB pathway as blocking macrophage Mincle inhibited Syk/NF-κB-driven skin lesions and epidermal injury in vivo and in vitro. We also found that LPS induced Mincle expression by M1 macrophages via the PU.1-dependent mechanism. Most importantly, we revealed that targeting Mincle with a neutralizing antibody significantly improved psoriasis in mice. In summary, our findings demonstrated that macrophages mediate psoriasis in mice via the Mincle-dependent mechanism, targeting Mincle may represent as a novel therapy for psoriasis. A simplified pathway model of Mincle in macrophage-mediated psoriasis.

Autoimmune bullous diseases in pregnancy: an overview of pathogenesis, clinical presentations, diagnostics and available therapies

Autoimmune bullous diseases (AIBDs) are rare organ-specific diseases characterized by the appearance of blisters and erosions on the skin and mucous membranes. These dermatoses are marked by the development of autoantibodies targeting the autoantigens located in intercellular junctions, i.e., between keratinocytes or in the basement membrane area. Therefore, the fundamental division of AIBDs into the pemphigus and pemphigoid groups exists. Although AIBDs are uncommon in the general population, their overall incidence is somewhat higher in women of all ages, for which a pregnant women can be likely affected too. While the pemphigoid gestationis is exclusive bullous dermatosis of pregnancy, the other AIBDs can also start or worsen during this period. The appearance of AIBDs in childbearing women is a particularly sensitive situation requiring exceptional clinicians' caution due to the possibility of pregnancy complications with adverse effects and risks to the mother and the child. Also, there are numerous management difficulties in the period of pregnancy and lactation related to the drugs' choice and safety. This paper aimed to outline the pathophysiologic mechanisms, clinical manifestations, diagnostic approach and therapy of the most commonly recognized AIBDs in pregnancy.

Serum LL‐37 and inflammatory cytokines levels in psoriasis

Background

Psoriasis (PsO) is a T‐cell‐associated inflammatory autoimmune dermatitis. Leucine leucine‐37 (LL‐37) is upregulated in PsO patients and correlated with the area and severity of PsO. However, the exact relation between LL‐37 and T cell‐associated inflammation is not well understood. It is very important to clarify the relationship between LL‐37 and inflammatory response for clinical diagnosis and treatment of PsO. This study investigated the serum levels of LL‐37 and inflammatory cytokines, as well as correlations between them in PsO patients, which aimed to provide new ideas for the diagnosis and treatment of PsO.

Methods

PsO patients (n = 50) and healthy volunteers (n = 33) were recruited in this study. Skin specimens were stained with hematoxylin and eosin (H&E). The serum levels of LL‐37, T‐helper type 1 (Th1, IFN‐γ), T‐helper type 17 (Th17, IL‐17), T‐helper type 22 (Th22, IL‐22), and T‐helper type 2 cytokines (Th2, IL‐4) were assessed by enzyme‐linked immunosorbent assay. Some of the patients were re‐recruited after treatment to evaluate LL‐37 and cytokines levels.

Results

Pathological changes were observed in PsO skin lesions. LL‐37, IFN‐γ, IL‐17, and IL‐22 serum levels were much higher in PsO patients than those in healthy volunteers (p < .001), and posttreatment reduction was observed in five patients. However, no remarkable difference in IL‐4 level (p > .05) was found. LL‐37 level was positively correlated with IFN‐γ, IL‐17, and IL‐22 levels (p < .001) in PsO patients.

Conclusion

LL‐37 expression was significantly associated with inflammatory response, which may provide us new ideas for diagnosing and monitoring disease activity of PsO.

Reactive Oxygen Species-Responsive Gel-Based Microneedle Patches for Prolonged and Intelligent Psoriasis Management

Psoriasis is an inflammatory skin disease. Microneedle (MN) patches can improve psoriasis treatment outcomes by increasing local drug content in the skin. As psoriasis frequently relapses, developing intelligent MN-based drug delivery systems with prolonged therapeutic drug levels and improved treatment efficiency is of great significance. Here, we designed detachable H₂O₂-responsive gel-based MN patches containing methotrexate (MTX) and epigallocatechin gallate (EGCG) by using EGCG as both cross-linkers for needle-composited materials and anti-inflammatory drugs. The gel-based MNs had dual-mode drug release kinetics, which quickly released MTX diffusively and sustainably released EGCG in an H₂O₂-responsive way. Compared with dissolving MNs, the gel-based MNs extended skin retention of EGCG, leading to prolonged reactive oxygen species (ROS) scavenging effects. The ROS-responsive MN patches that transdermally delivered antiproliferative and anti-inflammatory drugs improved treatment outcomes in both psoriasis-like and prophylactic psoriasis-like animal models.

Psoriatic Arthritis: Pathogenesis and Targeted Therapies

Psoriatic arthritis (PsA), a heterogeneous chronic inflammatory immune-mediated disease characterized by musculoskeletal inflammation (arthritis, enthesitis, spondylitis, and dactylitis), generally occurs in patients with psoriasis. PsA is also associated with uveitis and inflammatory bowel disease (Crohn's disease and ulcerative colitis). To capture these manifestations as well as the associated comorbidities, and to recognize their underlining common pathogenesis, the name of psoriatic disease was coined. The pathogenesis of PsA is complex and multifaceted, with an interplay of genetic predisposition, triggering environmental factors, and activation of the innate and adaptive immune system, although autoinflammation has also been implicated. Research has identified several immune-inflammatory pathways defined by cytokines (IL-23/IL-17, TNF), leading to the development of efficacious therapeutic targets. However, heterogeneous responses to these drugs occur in different patients and in the different tissues involved, resulting in a challenge to the global management of the disease. Therefore, more translational research is necessary in order to identify new targets and improve current disease outcomes. Hopefully, this may become a reality through the integration of different omics technologies that allow better understanding of the relevant cellular and molecular players of the different tissues and manifestations of the disease. In this narrative review, we aim to provide an updated overview of the pathophysiology, including the latest findings from multiomics studies, and to describe current targeted therapies.

Considerations of the Genetic Background of Obesity among Patients with Psoriasis

Psoriasis comorbidities may emerge from pleiotropic mechanisms, including common proinflammatory pathways, cellular mediators or genetic predisposition. Obesity is considered to be an independent risk factor of psoriasis, which may influence the severity of the disease and its early onset, decrease patients’ quality of life, alter response to psoriasis therapies and affect morbidity by reduced life expectancy due to cardiovascular events. Although novel approaches, including genetic techniques, have provided a wide range of new research, there are still scarce studies elaborating on the common genetic background of psoriasis and obesity. The aim of this study was to present and evaluate a possible common genetic background of psoriasis and concomitant increased body mass based on the review of the available literature.

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.

Natural Plant Extract - Loganin: A Hypothesis for Psoriasis Treatment Through Inhibiting Oxidative Stress and Equilibrating Immunity via Regulation of Macrophage Polarization

Psoriasis, a chronic immune-mediated inflammatory skin disease, influences approximately 2-3% of the world's population. At present, the etiology of psoriasis remains unclear and there is still no causal treatment available. Recent studies indicate that oxidative stress (OS) and T cells dysregulation may participate in the pathogenesis of psoriasis, among which M1-dominant macrophage polarization is a crucial contributor. Macrophages mainly polarize into two different subsets, ie, classically activated macrophage (M1) and alternatively activated macrophage (M2). M1 polarization tends to exacerbate psoriasis via producing substantial reactive oxygen species (ROS) and inflammatory mediators, to encourage OS invasion and T cells dysregulation. Thus, targeting M1 polarization can be a possible therapeutic alternative for psoriasis. Loganin, belonging to iridoid glycosides, is a pharmaceutically active ingredient originated from Cornus officinalis, exerting multiple biological activities, eg, immunomodulation, antioxidation, anti-inflammation, etc. More importantly, it could effectively suppress M1 polarization, thereby arresting OS aggression and T cells' dysregulation. Numerous studies have confirmed that loganin is quite reliable for diseases treatment via suppressing M1 polarization. Nevertheless, reports about loganin treating psoriasis have seldom appeared so far. Accordingly, we hold a hypothesis that loganin would availably manage psoriasis through preventing M1 polarization. Data from previous studies guarantee the potential of loganin in control of psoriasis.

Exploration of the underlying comorbidity mechanism in psoriasis and periodontitis: a bioinformatics analysis

BACKGROUND

Increasing evidence indicates that psoriasis (PSO) and periodontitis (PD) are likely to occur together, however, the underlying mechanism remains unclear.

MATERIALS AND METHODS

The expression profiles of PSO (lesion vs non-lesion, GSE30999, GSE14905) and PD (affected vs unaffected gingival tissue, GSE16134, GSE10334) were downloaded from the GEO database. First, we investigated the common differentially expressed genes (DEGs) of PSO and PD. Then, GO and KEGG enrichment analysis, protein interaction network (PPI) construction, and hub gene identification analysis were carried out. Finally, GO and KEGG enrichment analysis, miRNA interaction analysis, and transcription factors (TFs) interaction analysis for hub genes were performed.

RESULTS

Eighteen DEGs were identified for further analysis, including 15 up-regulated genes and 3 down-regulated genes. 9 hub genes were then identified via Cytohubba, including IL1B, CXCL1, CXCL8, MMP12, CCL18, SELL, CXCL13, FCGR3B, and SELE. Their functions are mainly enriched in two aspects: neutrophil chemotaxis and migration, chemokine activation and interaction. The enriched signaling pathways includes three categories: host defense, inflammation-related signaling pathways, and disease-related pathways. 9 common miRNAs based on experimental evidence and 10 common TFs were further identified in both PSO and PD.

CONCLUSION

Our study revealed possible comorbidity mechanisms in PSO and PD from the perspective of bioinformatics tentatively. The data can present new insight for joint prevention and treatment of in PSO and PD, as well as provide data support for further prospective studies.

Comprehensive Insight into Lichen Planus Immunopathogenesis

Lichen planus is a chronic disease affecting the skin, appendages, and mucous membranes. A cutaneous lichen planus is a rare disease occurring in less than 1% of the general population, while oral illness is up to five times more prevalent; still, both forms equally impair the patient's quality of life. The etiology of lichen planus is not entirely understood. Yet, immune-mediated mechanisms have been recognized since environmental factors such as hepatitis virus infection, mechanical trauma, psychological stress, or microbiome changes can trigger the disease in genetically susceptible individuals. According to current understanding, lichen planus immunopathogenesis is caused by cell-mediated cytotoxicity, particularly cytotoxic T lymphocytes, whose activity is further influenced by Th1 and IL-23/Th-17 axis. However, other immunocytes and inflammatory pathways complement these mechanisms. This paper presents a comprehensive insight into the actual knowledge about lichen planus, with the causal genetic and environmental factors being discussed, the immunopathogenesis described, and the principal effectors of its inflammatory circuits identified.

Benvitimod inhibits MCM6-meditated proliferation of keratinocytes by regulating the JAK/STAT3 pathway

BACKGROUND

Benvitimod (Tapinarof), as a small-molecule topical therapeutical aryl hydrocarbon receptor (AHR)-modulating agent, is in clinical development for treating psoriasis and atopic dermatitis. Benvitimod reduces proinflammatory cytokines in psoriasis by specifically binding and activation of AHR. However, whether benvitimod can inhibit keratinocyte proliferation remains unclear. Minichromosome maintenance protein 6 (MCM6) is a key element of the prereplication complex (pre-RC) assembly which is one of the essential steps in the initiation of DNA replication for cell proliferation.

OBJECTIVES

This study aimed to determine whether benvitimod could reduce the excessive proliferation of psoriatic keratinocytes by inhibiting MCM6.

METHODS

We examined the inhibitory effect of benvitimod on MCM6-mediated proliferation of keratinocytes by HaCaT cells in vitro and an IMQ-induced psoriatic model of mice in vivo.

RESULTS

Epidermal MCM6 expression was enhanced in the skin lesions of psoriatic patients. The experiments further revealed that MCM6 was required for the proliferation of keratinocytes and governed by the IL-22/STAT3 pathway. In addition, the antiproliferation effect of benvitimod is achieved by the inhibition of p-JAK1 and p-JAK2, which further restrained the activation of STAT3 in keratinocytes. Lastly, benvitimod could repressed imiquimod-induced skin lesions and the expression of epidermal MCM6 and p-STAT3 in mice. Moreover, knockdown of AHR in keratinocytes enhanced the activation of JAK1 and JAK2.

CONCLUSION

The findings reveal that benvitimod could decrease MCM6-mediated proliferation of keratinocytes by affecting the JAK/STAT3 pathway, thereby serving as a new treatment modality for psoriasis.

STAT2/Caspase3 in the diagnosis and treatment of psoriasis

BACKGROUND

Psoriasis is a classic chronic recurrent inflammatory skin disease characterized by skin inflammation and abnormal biological behaviour of keratinocytes. Although Signal Transducer And Activator Of Transcription 2 (STAT2) was found to play an important role in the Janus kinase (JAK)-STAT signalling pathway and contribute to the pathogenesis of psoriasis, its exact role in psoriasis remains unclear.

METHODS

Using bioinformatics analysis, we identified the key pathways that significantly impacted psoriatic lesions. After identifying the critical molecule gene differentially expressed in multiple public databases using the Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analysis, clinical samples were collected to validate the gene's significance. Its functions and underlying mechanism were also investigated in vitro. Lastly, we evaluated the diagnostic and therapeutic power of the target gene using the receiver operating characteristic curve (ROC), and gene association was assessed using Spearman correlation.

RESULTS

A significant correlation was found between cysteine-aspartic acid protease3 (Caspase3) and STAT2, and functional enrichment analysis revealed that they were both significantly up-regulated in psoriatic skin lesions compared to non-lesional tissues. Functional analysis revealed that Caspase3 functioned downstream of STAT2 in psoriasis. Lastly, we found that Caspase3 and STAT2 could be potential biomarkers for diagnosing and treating psoriasis.

CONCLUSIONS

In summary, STAT2 overexpression contributes to psoriasis progression by regulating Capase3 phosphorylation to induce excessive apoptosis of keratinocytes. Meanwhile, STAT2 and Capase3 were identified as promising biomarkers for the diagnosis and treatment of psoriasis and could be used for individualized treatments.

Autophagy Inhibits Inflammation via Down-Regulation of p38 MAPK/mTOR Signaling Cascade in Endothelial Cells

Objective

Autophagy, an intracellular process of self-digestion, has been shown to modulate inflammatory responses. In the present study, we determined the effects of autophagy on inflammatory response induced by M5 cytokines.

Methods

Human umbilical vein endothelial cells (HUVECs) were treated with M5 cytokines to induce inflammation. Expression levels of mRNA for inflammatory cytokines and BIRC2 were compared in HUVECs with vs without induction of autophagy with rapamycin (RAPA) by PCR, while cell apoptosis was assessed by flow cytometry and caspase-3 activity assay kit. Expression levels of LC3, p62, p-p38 MAPK (Thr180/Tyr182), p-mTOR (Ser2445) and p-ULK1 (Ser555) proteins were measured by Western blotting. The nitric oxide (NO) content, NO synthase (NOS) activity and cell angiogenesis were also evaluated.

Results

Induction of autophagy with RAPA decreased expression levels of IL6, IL8 and CCL20, in addition to reduction in inflammation-induced apoptosis in HUVECs. Moreover, RAPA increased LC3II, while decreasing p62 expression. Likewise, expression levels of p-p38 MAPK and p-mTOR proteins were markedly decreased by the treatment with RAPA. Finally, RAPA treatment increased the NO content and the NOS activity, and inhibited angiogenesis.

Conclusion

Induced autophagy can improve the function of endothelial cells in psoriasis, suggesting approaches to induce autophagy can be used to ameliorate psoriasis.

TRPV1: A promising therapeutic target for skin aging and inflammatory skin diseases

TRPV1 is a non-selective channel receptor widely expressed in skin tissues, including keratinocytes, peripheral sensory nerve fibers and immune cells. It is activated by a variety of exogenous or endogenous inflammatory mediators, triggering neuropeptide release and neurogenic inflammatory response. Previous studies have shown that TRPV1 is closely related to the occurrence and/or development of skin aging and various chronic inflammatory skin diseases, such as psoriasis, atopic dermatitis, rosacea, herpes zoster, allergic contact dermatitis and prurigo nodularis. This review summarizes the structure of the TRPV1 channel and discusses the expression of TRPV1 in the skin as well as its role of TRPV1 in skin aging and inflammatory skin diseases.

The Presence of Psoriasis, Metabolic Syndrome and Their Combination Increases the Serum Levels of CRP and CD5L but Not sCD200R1 and sTLR2 in Participants

Psoriasis and metabolic syndrome (MetS) are chronic inflammatory conditions associated with the dysregulation of immune system reactivity. The inflammatory processes of both diseases have not yet been fully characterized, and the evaluation of proteins/markers that could be involved in their pathogenesis is of great importance. We selected four markers: CRP, sCD200R1, CD5L, and sTLR2; in particular, sCDR2001 has not yet been measured in the context of psoriasis and metabolic syndrome. Material and methods: In the study, 64 controls and 43 patients with psoriasis with or without a metabolic syndrome were enrolled. The levels of selected markers were measured using ELISA kits. Results: CRP levels were significantly higher in psoriasis patients, especially in the subgroup of patients with MetS compared to nonMetS patients (p < 0.01). sCD200R1 and sTLR2 were not significantly different between groups and subgroups; however, CD200R1 levels were slightly higher in both control groups compared to both groups of patients. CD5L levels were significantly higher in patients with MetS compared to nonMets patients (p < 0.02). We also evaluated the correlations between parameters in controls and patients’ groups, as well as in subgroups. Correlations between BMI and CRP were found in all groups and subgroups. Other correlations were group- and subgroup-specific. For example, in the patients’ group, CD5L correlated with sCD200R1 (p < 0.05) and in MetS controls, with age (p < 0.03). Conclusion: The results show that the presence of systemic inflammation associated with psoriasis and metabolic syndrome and their combination alters the expression of specific molecules, especially CRP and CD5L, which were significantly increased in patients with psoriasis and a metabolic syndrome compared to controls without metabolic syndromes. Correlations between CRP and BMI in all groups suggest that overweight and obesity increase the intensity of inflammation and potentiate CD5L expression. In contrast, levels of molecules that may limit inflammation were not increased in psoriasis and metabolic syndrome subjects (they were non-significantly lower compared with healthy controls), which may reflect the chronic nature of both diseases and the exhaustion of inhibitory mechanisms.

Effect of Azelaic Acid on Psoriasis Progression Investigated Based on Phosphatidylinositol 3-Kinase (PI3K)/Protein Kinase B (AKT) Signaling Pathway

OBJECTIVE

To probe into the effect of azelaic acid on psoriasis based on the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway.

METHODS

Psoriasis gene expression data were downloaded from the GEO database for differential expression analysis to identify differentially expressed genes (DEGs). KEGG and GSEA analyses were performed to identify important signaling pathways that may be involved in psoriasis progression for subsequent validation. Thirty-six C57BL/6 mice aged 8 weeks old were randomly assigned into the blank control group (n = 9), negative control group (n = 9), psoriasis model group (n = 9), and azelaic acid treat group (n = 9). Mice models of psoriasis were prepared with imiquimod (IMQ) in the latter two groups, and azelaic acid ointment was applied in azelaic acid treat group. Then, hematoxylin-eosin (HE) staining was carried out to detect the effect of azelaic acid on the pathological damage of mice models of psoriasis in each group. HaCaT cells cultured in vitro were divided into blank control group, negative control group (addition of azelaic acid), IL-17 group (20 ng/mL) and IL-17+azelaic acid group, with 3 replicates for each group. Immunofluorescence assay and Western blotting were used to detect the protein expression of PI3K/AKT signaling pathway related molecules.

RESULTS

KEGG analysis showed that DEGs were significantly enriched in PI3K-AKT signaling pathway. GSEA analysis showed that PI3K and MTOR signaling pathways were up-regulated in psoriasis, while AUTOPHAGY signaling pathway was down-regulated. HE staining showed that azelaic acid could significantly inhibit the local skin injury in mice caused by IMQ-induced psoriasis. Moreover, azelaic acid can inhibit the expression of PI3K/AKT signaling pathway related proteins phosphorylated (p)-PI3K, p-AKT, p-mammalian target of rapamycin (mTOR), vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2), angiogenin-1 and hypoxia-inducible factor-1α (HIF-1α). These results imply that azelaic acid may inhibit the activation of PI3K/AKT signaling pathway and angiogenesis, thereby improving the symptoms of psoriasis.

CONCLUSION

Azelaic acid may inhibit the activation of PI3K/AKT signaling pathway and angiogenesis, thereby improving the symptoms of psoriasis.

Neutrophils inhibit γδ T cell functions in the imiquimod-induced mouse model of psoriasis

Background

Psoriasis is a chronic skin disease associated with deregulated interplays between immune cells and keratinocytes. Neutrophil accumulation in the skin is a histological feature that characterizes psoriasis. However, the role of neutrophils in psoriasis onset and development remains poorly understood.

Methods

In this study, we utilized the model of psoriasiform dermatitis, caused by the repeated topical application of an imiquimod containing cream, in neutrophil-depleted mice or in mice carrying impairment in neutrophil functions, including p47phox -/- mice (lacking a cytosolic subunit of the phagocyte nicotinamide adenine dinucleotide phosphate - NADPH - oxidase) and Sykfl/fl MRP8-cre+ mice (carrying the specific deletion of the Syk kinase in neutrophils only), to elucidate the specific contribution of neutrophils to psoriasis development.

Results

By analyzing disease development/progression in neutrophil-depleted mice, we now report that neutrophils act as negative modulators of disease propagation and exacerbation by inhibiting gammadelta T cell effector functions via nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-mediated reactive oxygen species (ROS) production. We also report that Syk functions as a crucial molecule in determining the outcome of neutrophil and γδ T cell interactions. Accordingly, we uncover that a selective impairment of Syk-dependent signaling in neutrophils is sufficient to reproduce the enhancement of skin inflammation and γδ T cell infiltration observed in neutrophil-depleted mice.

Conclusions

Overall, our findings add new insights into the specific contribution of neutrophils to disease progression in the IMQ-induced mouse model of psoriasis, namely as negative regulatory cells.

Single-Cell RNA Sequencing Reveals the Immune Cell Profiling in IMQ Induced Psoriasis-Like Model

PURPOSE

Psoriasis is a chronic systemic inflammatory skin disease with a high recurrence rate. The immune response plays an important role in psoriasis. However, the subsets of immune cells involved in inflammation in psoriatic mice have not been fully studied. This study showed the immune environment characteristics of psoriasis in mice.

METHODS

We used single-cell RNA sequencing (10× Genomics) as an unbiased analytical strategy to investigate the heterogeneity of skin immune cells in imiquimod-induced psoriasis mice systematically.

RESULTS

We identified 10 major clusters and their marker genes among 14,439 cells. The proportions of macrophages, NK/T cells, conventional dendritic cells (cDCs) and plasmacytoid dendritic cells (pDCs) were increased in psoriatic mice. Macrophages were the largest group and were further divided into 7 subgroups, and all macrophage clusters were increased in psoriatic mice. Differentially expressed genes in control versus psoriatic mice skin lesions showed that Fcgr4, Saa3 and Acp5 in macrophages, Acp5, Fcgr4 and Ms4a6d in NK/T cells, Saa3 in cDCs, and Ifitm1 in pDCs were upregulated in psoriasis mice. Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway enrichment analysis emphasized the role of oxidative phosphorylation signals and antigen processing and presentation signals in murine psoriasis-like models.

CONCLUSION

Our study reveals the immune environment characteristics of the commonly used IMQ induced psoriasis-like models and provides a systematic insight into the immune response of mice with psoriasis, which is conducive to comparing the similarities and differences between the mouse model and human psoriasis.

Mechanisms and inhibitors of ferroptosis in psoriasis

Psoriasis is a chronic inflammatory skin disease that features localized or widespread erythema, papules, and scaling. It is common worldwide and may be distributed throughout the whole body. The pathogenesis of psoriasis is quite complex and the result of the interplay of genetic, environmental and immune factors. Ferroptosis is an iron-dependent programmed death that is different from cell senescence, apoptosis, pyroptosis and other forms of cell death. Ferroptosis involves three core metabolites, iron, lipids, and reactive oxygen species (ROS), and it is primarily driven by lipid peroxidation. Ferrostatin-1 (Fer-1) is an effective inhibitor of lipid peroxidation that inhibited the changes related to ferroptosis in erastin-treated keratinocytes and blocked inflammatory responses. Therefore, it has a certain effect on the treatment of psoriatic lesions. Although ferroptosis is closely associated with a variety of human diseases, such as inflammatory diseases, no review has focused on ferroptosis in psoriasis. This mini review primarily focused on the pathogenesis of psoriasis, the mechanisms of ferroptosis, the connection between ferroptosis and psoriasis and ferroptosis inhibitors in psoriasis treatment. We discussed recent research advances and perspectives on the relationship between ferroptosis and psoriasis.

The Dopamine Gene Receptors (DRD1-5) Expression Alteration in Psoriasis Patients

BACKGROUND

Psoriasis is a chronic inflammatory autoimmune disease that is considered linked to genetic and environmental factors such as stress. Since the neurotransmitter dopamine has a close association with stress configuration, it can be a candidate for relieving psoriasis representation. In addition to the CNS, immune cells can play a decisive role in regulating immune functions through dopamine synthesis and the expression of its receptors. Altered response of immune cells to dopamine as well as a distorted expression of dopamine receptors (DRs) in immune cells have been reported in some chronic inflammatory conditions.

OBJECTIVE

This study aims the evaluation of dopamine receptor (DR1-DR5) gene expression in mononuclear blood cells of psoriatic patients in comparison with normal individuals.

METHODS

We isolated peripheral mononuclear cells (PBMCs) from blood samples followed by total RNA extraction, cDNA synthesis, and real-time PCR using specific primer pairs.

RESULTS

We found that all types of DRs are expressed in the PBMCs of normal and psoriatic individuals. We also concluded that compared to controls, DR2 and DR4 were overexpressed in psoriasis patients while DR3 was low-expressed.

CONCLUSION

Increased expression of DR2 and DR4 along with decreased expression of DR3 in PBMCs of psoriasis patients not only provide new insight into the pathogenesis of psoriasis but may also be effective in designing future therapeutic strategies attributable to psoriasis.

Vitamin D Signaling in Psoriasis: Pathogenesis and Therapy

Psoriasis is a systemic, chronic, immune-mediated disease that affects approximately 2–3% of the world’s population. The etiology and pathophysiology of psoriasis are still unknown, but the activation of the adaptive immune system with the main role of T-cells is key in psoriasis pathogenesis. The modulation of the local neuroendocrine system with the downregulation of pro-inflammatory and the upregulation of anti-inflammatory messengers represent a promising adjuvant treatment in psoriasis therapies. Vitamin D receptors and vitamin D-mediated signaling pathways function in the skin and are essential in maintaining the skin homeostasis. The active forms of vitamin D act as powerful immunomodulators of clinical response in psoriatic patients and represent the effective and safe adjuvant treatments for psoriasis, even when high doses of vitamin D are administered. The phototherapy of psoriasis, especially UVB-based, changes the serum level of 25(OH)D, but the correlation of 25(OH)D changes and psoriasis improvement need more clinical trials, since contradictory data have been published. Vitamin D derivatives can improve the efficacy of psoriasis phototherapy without inducing adverse side effects. The anti-psoriatic treatment could include non-calcemic CYP11A1-derived vitamin D hydroxyderivatives that would act on the VDR or as inverse agonists on RORs or activate alternative nuclear receptors including AhR and LXRs. In conclusion, vitamin D signaling can play an important role in the natural history of psoriasis. Selective targeting of proper nuclear receptors could represent potential treatment options in psoriasis.

Chromosomal Aberrations and Oxidative Stress in Psoriatic Patients with and without Metabolic Syndrome

Psoriasis and metabolic syndrome (MetS), a common comorbidity of psoriasis, are associated with mild chronic systemic inflammation that increases oxidative stress and causes cell and tissue damage. At the cellular level, chromosomal and DNA damage has been documented, thus confirming their genotoxic effect. The main objective of our study was to show the genotoxic potential of chronic inflammation and determine whether the presence of both pathologies increases chromosomal damage compared to psoriasis alone and to evaluate whether there are correlations between selected parameters and chromosomal aberrations in patients with psoriasis and MetS psoriasis. Clinical examination (PASI score and MetS diagnostics according to National Cholesterol Education Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults; NCE/ATPIII criteria), biochemical analysis of blood samples (fasting glucose, total cholesterol, low density and high density lipoproteins; LDL, HDL, non-HDL, and triglycerides;TAG), DNA/RNA oxidative damage, and chromosomal aberration test were performed in 41 participants (20 patients with psoriasis without MetS and 21 with MetS and psoriasis). Our results showed that patients with psoriasis without metabolic syndrome (nonMetS) and psoriasis and MetS had a higher rate of chromosomal aberrations than the healthy population for which the limit of spontaneous, natural aberration was <2%. No significant differences in the aberration rate were found between the groups. However, a higher aberration rate (higher than 10%) and four numerical aberrations were documented only in the MetS group. We found no correlations between the number of chromosomal aberrations and the parameters tested except for the correlation between aberrations and HDL levels in nonMetS patients (rho 0.44; p < 0.02). Interestingly, in the MetS group, a higher number of chromosomal aberrations was documented in non-smokers compared to smokers. Data from our current study revealed an increased number of chromosomal aberrations in patients with psoriasis and MetS compared to the healthy population, especially in psoriasis with MetS, which could increase the genotoxic effect of inflammation and the risk of genomic instability, thus increasing the risk of carcinogenesis.

Dendritic Cells and Macrophages in the Pathogenesis of Psoriasis

Psoriasis is a chronic inflammatory skin disease characterized by scaly indurated erythema. This disease impairs patients’ quality of life enormously. Pathological findings demonstrate proliferation and abnormal differentiation of keratinocytes and massive infiltration of inflammatory immune cells. The pathogenesis of psoriasis is complicated. Among immune cells, dendritic cells play a pivotal role in the development of psoriasis in both the initiation and the maintenance phases. In addition, it has been indicated that macrophages contribute to the pathogenesis of psoriasis especially in the initiation phase, although studies on macrophages are limited. In this article, we review the roles of dendritic cells and macrophages in the pathogenesis of psoriasis.

Rosmarinic acid ameliorated psoriatic skin inflammation in mice through the novel inhibition of the interleukin-17A/interleukin-17A receptor interaction

The interaction between interleukin-17A (IL-17A) and IL-17A receptor (IL-17RA) is a crucial target of psoriasis. Several natural compounds from foods or herbs have displayed efficacies on the amelioration of psoriasis. However, the anti-psoriatic mechanisms are mostly through the common anti-inflammatory effects and rarely via the blockage of the IL-17A/IL-17RA interaction. In this study, the IL-17A/IL-17RA-targeting effects of phenylpropanoids, a large class of secondary metabolites in plants, were analyzed. By screening 17 phenylpropanoids, we found that top four compounds with IL-17A/IL-17RA-blocking abilities were rosmarinic acid, eugenol, syringic acid, and gallic acid, with inhibitory concentrations at 50% of 2.14 ± 0.35 mM, 6.35 ± 0.1 mM, 4.79 ± 0.2 mM, and >10 mM, respectively. The oral administration of rosmarinic acid ameliorated redness and scaling on the dorsal skin of imiquimod-induced psoriatic mice in a dose-dependent manner. Rosmarinic acid suppressed the production of IL-23 and IL-17A and the infiltration of granulocyte subsets in skin tissues. Docking analysis showed that rosmarinic acid docked into IL-17A/IL-17RA interaction regions and exhibited hydrogen bonding with Arg-61, Glu-68, Arg-100, and Ser-118 of IL-17A, which are located in the epitope regions recognized by IL-17A neutralizing antibodies Fab6785 and Fab6468. In conclusion, this is the first study reporting that rosmarinic acid is an IL-17A-targeting agent that ameliorates psoriatic skin inflammation in mice via blocking the IL-17A/IL-17RA interaction.

A Modified Hyaluronic Acid–Based Dissolving Microneedle Loaded With Daphnetin Improved the Treatment of Psoriasis

Psoriasis is a common chronic immune-inflammatory disease. Challenges exist in the present treatment of psoriasis, such as difficulties in transdermal drug administration and severe side effects. We hope to achieve a better therapeutic outcome for psoriasis treatment. By using modified soluble microneedles (MNs) loaded with daphnetin, the psoriasis symptoms of mice, the abnormal proliferation of keratinocytes, and the secretion of inflammatory factors were significantly reduced. In vitro, daphnetin is proven to inhibit the NF-κB signaling pathway and to inhibit the proliferation of HaCaT cells and the release of inflammatory factors, especially CCL20. This research showed that the modified microneedle loaded with daphnetin optimized transdermal drug delivery and relieved the symptoms of psoriasis more effectively. The novel route of Daph administration provides a future research direction for the treatment of psoriasis.

Laser-assisted nanocarrier delivery to achieve cutaneous siRNA targeting for attenuating psoriasiform dermatitis

Psoriasis is an autoimmune skin disorder presenting the excessive expression of interleukin (IL)-6. The topical use of small interfering RNA (siRNA) has been increasingly discovered for treating skin diseases. A delivery system capable of protecting siRNA while facilitating both skin targeting and cellular entrance is critical for the successful medication of topically-applied siRNA. Herein, we developed a delivery system for siRNA based on poly(lactic-co-glycolic acid) (PLGA) nanoparticles and combined this system with an ablative laser to promote skin absorption for topical psoriasis therapy. The siRNA absorption enhancement was compared by two laser modalities: a fractional CO₂ laser and a fully-ablative Er:YAG laser. We characterized the effect of the delivery system by the cellular uptake, IL-6 silencing, in vitro skin absorption, cutaneous biodistribution, and in vivo psoriasiform dermatitis in mice. The nanocarriers showed minimal cytotoxicity and facile cellular uptake to knock down the IL-6 expression. The nanoformulation containing a cationic surfactant (Forestall) for ion pairing with siRNA achieved a 66% and 77% IL-6 knockdown efficiency toward keratinocytes and macrophages, respectively. In the Franz cell absorption, the lasers increased the naked siRNA penetration to the receptor compartment by 3.7-5.0-fold but remarkably reduced skin deposition using imiquimod (IMQ)-treated psoriasiform skin as the barrier. The fractional laser facilitated nanoparticle-associated siRNA skin deposition up to 3.3-fold, whereas the transport of the nanocarriers to the receptor was negligible. Qualitatively, the lasers increased nanoparticle delivery in the epidermis with limited effect to elevate the penetration depth. The fractional-mediated nanocarrier delivery dramatically attenuated the erythema and scaly lesions of psoriasiform dermatitis. The histological examination displayed a reduction of epidermal hyperplasia and macrophage infiltration by the combination of laser and nanosystem. The passive and laser-assisted naked siRNA delivery was less effective in mitigating dermatitis. The topical delivery of fractional laser-assisted nanoparticles on mice resulted in a 56% IL-6 knockdown. Our results manifested the benefit of cutaneous siRNA targeting using ablative lasers to deliver nanocarriers for treating psoriatic inflammation.

Updated Perspectives on Keratinocytes and Psoriasis: Keratinocytes are More Than Innocent Bystanders

Psoriasis is a complex disease triggered by genetic, immunologic, and environmental stimuli. Many genes have been linked to psoriasis, like the psoriasis susceptibility genes, some of which are critical in keratinocyte biology and epidermal barrier function. Still, the exact pathogenesis of psoriasis is unknown. In the disease, the balance between the proliferative and differentiative processes of keratinocytes becomes altered. Multiple studies have highlighted the role of dysregulated immune cells in provoking the inflammatory responses seen in psoriasis. In addition to immune cells, accumulating evidence shows that keratinocytes are involved in psoriasis pathogenesis, as discussed in this review. Although certain immune cell-derived factors stimulate keratinocyte hyperproliferation, activated keratinocytes can also produce anti-microbial peptides, cytokines, and chemokines that can promote their proliferation, as well as recruit immune cells to help initiate and reinforce inflammatory feedback loops. Psoriatic keratinocytes also show intrinsic differences from normal keratinocytes even after removal from the in vivo inflammatory environment; thus, psoriatic keratinocytes have been found to exhibit abnormal calcium metabolism and possible epigenetic changes that contribute to psoriasis. The Koebner phenomenon, in which injury promotes the development of psoriatic lesions, also provides evidence for keratinocytes' contributions to disease pathogenesis. Furthermore, transgenic mouse studies have confirmed the importance of keratinocytes in the etiology of psoriasis. Finally, in addition to immune cells and keratinocytes, data in the literature support roles for other cell types, tissues, and systems in psoriasis development. These other contributors are all potential targets for therapies, suggesting the importance of a holistic approach when treating psoriasis.

Chromatin accessibility and transcriptome integrative analysis revealed AP-1-mediated genes potentially modulate histopathology features in psoriasis

Background

Psoriasis is a chronic and hyperproliferative skin disease featured by hyperkeratosis with parakeratosis, Munro micro-abscess, elongation of rete pegs, granulosa thinning, and lymphocyte infiltration. We previously profiled gene expression and chromatin accessibility of psoriatic skins by transcriptome sequencing and ATAC-seq. However, integrating both of these datasets to unravel gene expression regulation is lacking. Here, we integrated transcriptome and ATAC-seq of the same psoriatic and normal skin tissues, trying to leverage the potential role of chromatin accessibility and their function in histopathology features.

Results

By inducing binding and expression target analysis (BETA) algorithms, we explored the target prediction of transcription factors binding in 15 psoriatic and 19 control skins. BETA identified 408 upregulated genes (rank product < 0.01) and 133 downregulated genes linked with chromatin accessibility. We noticed that cumulative fraction of genes in upregulation group was statistically higher than background, while that of genes in downregulation group was not significant. KEGG pathway analysis showed that the upregulated 408 genes were enriched in TNF, NOD, and IL-17 signaling pathways. In addition, the motif module in BETA suggested the 57 upregulated genes are targeted by transcription factor AP-1, indicating that increased chromatin accessibility facilitated the binding of AP-1 to the target regions and further induced expression of relevant genes. Among these genes, SQLE, STRN, EIF4, and MYO1B expression was increased in patients with hyperkeratosis, parakeratosis, and acanthosis thickening.

Conclusions

In summary, with the advantage of BETA, we identified a series of genes that contribute to the disease pathogenesis, especially in modulating histopathology features, providing us with new clues in treating psoriasis.