Severity, heterogeneity and systemic inflammation in psoriasis

Are periodontitis and psoriasis associated? A pre-clinical murine model

AIM

To investigate the bidirectional influence between periodontitis and psoriasis, using the respective experimental models of ligature- and imiquimod-induced diseases on murine models.

MATERIALS AND METHODS

Thirty-two C57/BL6J mice were randomly allocated to four experimental groups: control (P- Pso-), ligature-induced periodontitis (P+ Pso-), imiquimod-induced psoriasis (P- Pso+) and periodontitis and psoriasis (P+ Pso+). Samples (maxilla, dorsal skin and blood) were harvested immediately after death. Measures of periodontitis (distance between the cemento-enamel junction and alveolar bone crest [CEJ-ABC] and the number of osteoclasts) and psoriasis (epidermal thickness and infiltrate cell [/0.03mm2]) severity as well as systemic inflammation (IL-6, IL-17A, TNF-α) were collected.

RESULTS

The P+ Pso+ group exhibited the most severe experimental periodontitis and psoriasis, with the highest values of CEJ-ABC, number of osteoclasts, epidermal thickness and infiltrate cells in the dorsal skin, as well as the highest blood cytokine concentration. The P+ Pso- group presented with higher cell infiltrate (/0.03mm2) compared to the control group (p <.05), while the P- Pso+ group showed substantially higher alveolar bone loss (CEJ-ABC) than the control group (p <.05).

CONCLUSIONS

Experimental periodontitis may initiate and maintain psoriasiform skin inflammation and, vice versa, experimental psoriasis may contribute to the onset of periodontitis. In a combined model of the diseases, we propose a bidirectional association between periodontitis and psoriasis via systemic inflammation.

The Psoriasis Treatment Pipeline: An Overview and Update

Significant research advances in our understanding of psoriatic disease have led to the development of several highly selective, effective, and safe topical and systemic treatments. These treatments have led to unprecedented levels of disease clearance and control for most patients with psoriasis with cutaneous disease. However, there remains a need for improved treatments for those patients with recalcitrant disease, psoriatic arthritis, or nonplaque disease variants. Recently approved therapies and investigational products in ongoing clinical development programs that target IL-17A/F, IL-23, TYK2, PDE4, AhR or IL-36 cytokine signaling are improving the clinician's ability to care for a broader range of patients affected by psoriasis.

Treatment of periodontitis ameliorates the severity and extent of psoriasis-A randomized clinical trial

AIM

To assess the impact of non-surgical periodontitis treatment over conventional dermatological treatment on the severity and extent of psoriasis in patients affected by comorbid psoriasis and periodontitis.

METHODS

Seventy-four patients affected by both psoriasis and Stages I-IV periodontitis were randomized to receive either Steps 1-2 (non-surgical) of periodontal therapy (test group; n = 37) or no treatment (control group; n = 37). The two groups were balanced in terms of psoriasis medications, with the majority of the included patients undergoing biologics (74.0%) as monotherapy, while minor proportions were under systemic medications (13.7%) or none/topical/phototherapy (12.3%). The psoriasis area severity index (PASI) was regarded as the primary outcome. The Body Surface Area (BSA) and the Dermatology Life Quality Index (DLQI) were additionally considered as dermatological outcomes. Probing pocket depth, recession depth, clinical attachment level, periodontal inflamed surface area, and full-mouth plaque and bleeding scores were also measured. [Correction added on July 5, 2024, after first online publication: The preceding sentence has been revised].

RESULTS

Periodontal therapy in the test group led to statistically significant lower PASI scores at 10 weeks (mean = 3.15; standard deviation [SD] = 3.78) compared to the control group (mean = 7.11; SD = 6.09) (mean difference [MD] = -4.0; 95% confidence interval [CI]: -6.3, -1.6; p = .001). The test group also showed improvements in BSA (MD = -4.3) and periodontal parameters compared to the control group. DLQI only showed a non-statistically significant tendency (MD = -2.0).

CONCLUSION

Steps 1-2 of periodontal therapy showed an additional effect over conventional dermatological treatment in reducing the severity and extent of psoriasis (Clinicaltrials.gov: NCT05311501).

TAZ deficiency exacerbates psoriatic pathogenesis by increasing the histamine-releasing factor

BACKGROUND

Transcriptional coactivator with PDZ-biding motif (TAZ) is widely expressed in most tissues and interacts with several transcription factors to regulate cell proliferation, differentiation, and death, thereby influencing organ development and size control. However, very little is known about the function of TAZ in the immune system and its association with inflammatory skin diseases, so we investigated the role of TAZ in the pathogenesis of psoriasis.

RESULTS

Interestingly, TAZ was expressed in mast cells associated, particularly in lysosomes, and co-localized with histamine-releasing factor (HRF). TAZ deficiency promoted mast cell maturation and increased HRF expression and secretion by mast cells. The upregulation of HRF in TAZ deficiency was not due to increased transcription but to protein stabilization, and TAZ restoration into TAZ-deficient cells reduced HRF protein. Interestingly, imiquimod (IMQ)-induced psoriasis, in which HRF serves as a major pro-inflammatory factor, was more severe in TAZ KO mice than in WT control. HRF expression and secretion were increased by IMQ treatment and were more pronounced in TAZ KO mice treated with IMQ.

CONCLUSIONS

Thus, as HRF expression was stabilized in TAZ KO mice, psoriatic pathogenesis progressed more rapidly, indicating that TAZ plays an important role in preventing psoriasis by regulating HRF protein stability.

Association between the severity of hard-to-treat psoriasis and the prevalence of metabolic syndrome: A hospital-based cross-sectional study in Jakarta, Indonesia

Psoriatic lesions on the scalp, face, intertriginous, genitals, palms/soles, and nails are often delay diagnosed, hard-to-treat, and cause disability. Metabolic syndrome (MetS) is one of the most frequent and significant comorbidities in psoriasis. Many studies have discovered a link between psoriasis and MetS, but none have specifically assessed the hard-to-treat psoriasis in Indonesian population. This is a multicenter study involving four dermatology referral hospitals to investigate the association between psoriasis severity that has hard-to-treat lesions with the prevalence of MetS in Jakarta, Indonesia. Data was collected from April to October 2022. The severity of 84 hard-to-treat psoriasis patients was measured by Psoriasis Area Severity Index (PASI) scores. The participants divided into PASI score >10 (severe) and ≤ 10 (mild-moderate) groups. MetS was identified based on the modified National Cholesterol Education Program Adult Treatment Panel III. MetS was found in 64.3% of patients. Patients with a PASI score>10 had a significantly higher risk of metabolic syndrome compared to those with a score ≤ 10 (78.6% vs 50%, OR 3.667; 95% CI 1.413-9.514; p = 0.006). The prevalence of hypertension (p = 0.028), low levels of high-density lipoprotein (HDL) cholesterol (p = 0.01), mean fasting blood sugar (p = 0.018), and triglyceride levels (p = 0.044) between the two groups differed significantly. This study found most frequent components of MetS were abdominal obesity, decreased levels of HDL cholesterol, hypertension, hyperglycemia, and hypertriglyceridemia respectively. Individuals with severe hard-to-treat psoriasis had a 3.67 times more likely to have MetS rather than the mild-moderate group.

Prevalence, outcomes and associated factors of SARS-CoV-2 infection in psoriasis patients of Southwest China: a cross-sectional survey

In this study we aimed to investigate the prevalence of SARS-CoV-2 infection in psoriasis patients, and outcomes of SARS-CoV-2 infection and associated risk factors. A cross-sectional survey was conducted from February 2023 to March 2023. Information was obtained with online questionnaire about psoriasis patients on demographic characteristics, clinical characteristics, SARS-CoV-2 infection and outcomes, vaccination, and routine protection against COVID-19. Logistic regression analysis was used to explore risk factors with SARS-CoV-2 infection and exacerbation of psoriasis. A total of 613 participants were recruited. 516 (84.2%) were infected, and associated factors were sex, working status, routine protection against COVID-19, COVID-19 vaccination, impaired nail, infection exacerbate psoriasis, and severity of psoriasis. Among the patients infected with SARS-CoV-2, 30 (5.8%) required hospitalization, 122 (23.6%) had psoriasis exacerbation due to SARS-CoV-2 infection, and associated factors were subtype of psoriasis, discontinuation of psoriasis treatment during SARS-CoV-2 infection, response following COVID-19 vaccination, and severity of psoriasis. Booster dose vaccination contributed a low probability of COVID-19 sequelae. COVID-19 vaccine's effectiveness was unsatisfactory, while booster dose vaccination reduced the occurrence of COVID-19 sequelae in psoriasis patients of Southwest China. Patients treated with psoriasis shown to be safe, without a higher incidence of SARS-CoV-2 infection or COVID-19hospitalization compared to untreated patients. Stopping treatment during SARS-CoV-2 infection led to psoriasis exacerbation, so psoriasis treatment could be continued except severe adverse reaction.

Elevated serum IL-6 levels predict treatment interruption in patients with moderate to severe psoriasis: a 6-year real-world cohort study

BACKGROUND

Real-world, primary data on the treatment of psoriasis are scarce, especially concerning the role of soluble biomarkers as outcome predictors.

OBJECTIVE

The authors evaluated the utility of Th1/Th17 serum cytokines along with clinical characteristics as predictors of drug survival in the treatment of psoriasis.

METHODS

The authors consecutively included participants with moderate to severe psoriasis who were followed up for 6 years. Baseline interferon-α, tumor necrosis factor-α, and interleukin (IL)-2, IL-4, IL-6, IL-10, and IL-17A were measured using a cytometric bead array; clinical data were assessed. The authors calculated hazard ratios (HRs) for drug survival using a Cox proportional hazards model.

RESULTS

The authors included 262 patients, most of whom used systemic immunosuppressants or biologics. In the multivariate model, poor quality of life measured by the Dermatology Life Quality Index (HR = 1.04; 95% CI 1.01‒1.07; p = 0.012) and elevated baseline IL-6 (HR = 1.99; 95% CI 1.29‒3.08; p = 0.002) were associated with treatment interruption.

STUDY LIMITATIONS

The main limitation of any cohort study is the presence of confounders that could not be detected in clinical evaluation.

CONCLUSIONS

Poor quality of life and elevated baseline serum IL-6 level predicted treatment interruption in patients with moderate to severe psoriasis. Although IL-6 is not the most important mediator of the inflammatory pathway in the skin environment, it is an interesting biomarker candidate for predicting psoriasis treatment response.

Multi-target mechanism of Solanum xanthocarpum for treatment of psoriasis based on network pharmacology and molecular docking

Solanum xanthocarpum (SX) has been used to treat a variety of diseases, including skin disorders like psoriasis (PSO). SX possesses many pharmacological activities of anti-inflammatory, anti-cancer, immunosuppressive, and healing qualities. However, the multi-target mechanism of SX on PSO still needs clarity. Materials and methods: The Indian Medicinal Plants, Phytochemicals and Therapeutics (IMPPAT) database and the Swiss Target Prediction online tool were used to find the active phytochemical components and their associated target proteins. OMIM and GeneCards databases were used to extract PSO-related targets. A Venn diagram analysis determined the common targets of SX against PSO. Subsequently, the protein-protein interaction (PPI) network and core PPI target analysis were carried out using the STRING network and Cytoscape software. Also, utilising the online Metascape and bioinformatics platform tool, a pathway enrichment analysis of common targets using the Kyoto Encyclopaedia of Genes and Genome (KEGG) and Gene Ontology (GO) databases was conducted to verify the role of targets in biological processes, cellular components and molecular functions with respect to KEGG pathways. Lastly, molecular docking simulations were performed to validate the strong affinity between components of SX and key target receptors. Results: According to the IMPPAT Database information, 8 active SX against PSO components were active. According to the PPI network and core targets study, the main targets against PSO were EGFR, SRC, STAT3, ERBB2, PTK2, SYK, EP300, CBL, TP53, and AR. Moreover, molecular docking simulations verified the binding interaction of phytochemical SX components with their PSO targets. Last but not least, enrichment analysis showed that SX is involved in several biological processes, including peptidyl-tyrosine phosphorylation, peptidyl-tyrosine modification, and peptidyl-serine modification. The relevant KEGG signalling pathways are the PI3K-AKT signalling pathway, the EGFR tyrosine kinase inhibitor resistance pathway, and the MAPK signalling pathway. Conclusion: The network pharmacology technique, which is based on data interpretation and molecular docking simulation techniques, has proven the multi-target function of SX phytoconstituents.

Disease modification in inflammatory skin disorders: opportunities and challenges

Progress in understanding of the mechanisms underlying chronic inflammatory skin disorders, such as atopic dermatitis and psoriasis vulgaris, has led to new treatment options with the primary goal of alleviating symptoms. In addition, this knowledge has the potential to inform on new strategies aimed at inducing deep and therapy-free remission, that is, disease modification, potentially impacting on associated comorbidities. However, to reach this goal, key areas require further exploration, including the definitions of disease modification and disease activity index, further understanding of disease mechanisms and systemic spillover effects, potential windows of opportunity, biomarkers for patient stratification and successful intervention, as well as appropriate study design. This Perspective article assesses the opportunities and challenges in the discovery and development of disease-modifying therapies for chronic inflammatory skin disorders.

Inhibitors of dimerized translationally controlled tumor protein, a histamine releasing factor, may serve as anti-allergic drug candidates

It has been established that translationally controlled tumor protein (TCTP), also called histamine releasing factor (HRF), exhibits cytokine-like activities associated with initiation of allergic responses only after forming dimers (dTCTP). Agents that inhibit dTCTP by preventing its dimerization or otherwise block its function, also block development of allergic reactions, thereby serving as potential drugs to treat allergic diseases. Several lines of evidence have proven that peptides and antibodies that specifically inhibit the interactions between dTCTP and either its putative receptor or immunoglobulins exhibit significant in vivo efficacy as potential anti-inflammatory agents in murine models of allergic inflammatory diseases. This review highlights the development of several inhibitors targeting dTCTP and discusses how they affect the pathophysiologic processes of allergic and inflammatory diseases in several animal models and offers new perspectives on anti-allergic drug discovery.

The Role of Inflammation in the Pathogenesis of Psoriasis

"Psoriasis is a chronic inflammatory skin condition with genetic determinism characterized by the presence of welldefined, erythematous plaques, covered by white, pearly, stratified scales, located on the extension areas, the skin of the scalp, intertriginous regions. The origin of psoriasis is multifactorial, involving hereditary and environmental pathogenic mechanisms. It is triggered by various risk factors involving a variety of processes, such as inflammation, antigen presentation, cell signaling, and transcriptional regulation. "

Clinical Characteristics of Psoriasis for Initiation of Biologic Therapy: A Cluster Analysis

BACKGROUND

Psoriasis is a complex and heterogeneous disease that widely affects a patient's life. Biological therapy is usually prescribed in patients with severe psoriasis that do not respond to conventional treatment. However, data on the specific patient characteristics receiving biologics are still unavailable.

OBJECTIVE

To classify patients with psoriasis into subgroups with distinct phenotypes through cluster analysis, and to evaluate the differences between the clusters to predict disease prognosis by examining the response to biological therapy.

METHODS

The clinical characteristics of the patients with psoriasis were investigated and categorized using hierarchical cluster analysis. After clustering, the clinical characteristics of the patients were compared and the initiation of treatment with biologics according to the clusters were evaluated.

RESULTS

A total of 361 patients with psoriasis were classified into two clusters using 16 distinct clinical phenotypes. Group 1 (n=202) consisted of male smokers and alcohol users with higher psoriasis area and severity index (PASI), older age of onset, higher body mass index, and comorbidities including psoriatic arthritis, hypertension, and diabetes when compared to group 2 (n=159). Group 1 had a significantly higher probability of biological treatment initiation than group 2 (p=0.039). The measured risk factors for the initiation of biologics compared were PASI (p<0.001) and nail involvement (p=0.022).

CONCLUSION

Cluster analysis classified patients with psoriasis into two subgroups according to their clinical characteristics. Predicting the disease prognosis using a combination of specific clinical parameters may aid in the management of the disease.

Resolvins Lipid Mediators: Potential Therapeutic Targets in Alzheimer and Parkinson Disease

Inflammation and resolution are highly programmed processes involving a plethora of immune cells. Lipid mediators synthesized from arachidonic acid metabolism play a pivotal role in orchestrating the signaling cascades in the game of inflammation. The majority of the studies carried out so far on inflammation were aimed at inhibiting the generation of inflammatory molecules, whereas recent research has shifted more towards understanding the resolution of inflammation. Owing to chronic inflammation as evident in neuropathophysiology, the resolution of inflammation together with the class of lipid mediators actively involved in its regulation has attracted the attention of the scientific community as therapeutic targets. Both omega-three polyunsaturated fatty acids, eicosapentaenoic acid and docosahexaenoic acid, orchestrate a vital regulatory role in inflammation development. Resolvins derived from these fatty acids comprise the D-and E-series resolvins. A growing body of evidence using in vitro and in vivo models has revealed the pro-resolving and anti-inflammatory potential of resolvins. This systematic review sheds light on the synthesis, specialized receptors, and resolution of inflammation mediated by resolvins in Alzheimer's and Parkinson's disease.

Why targeted therapeutics have provided benefit in psoriasis: looking at IL-17 biology

INTRODUCTION

Psoriasis is an inflammatory, chronic and immune-mediated disease that can affect the skin and joints. Pro-inflammatory cytokines have a dominant role in the pathogenesis of this heterogeneous disease in which the IL-23/IL-17 axis plays a crucial role. The IL-17 family is involved in numerous processes such as immune defense, intestinal disorders and diseases of the central nervous system. In psoriasis, in particular, many cytokines belonging to the IL-17 family are involved in the inflammatory cascade underlying the disease.

AREAS COVERED

The knowledge of the mechanisms and pathways behind psoriasis is crucial for the development of new target therapies. We focused on IL-17 biology in order to understand why biological drugs against this cytokine are an effective treatment for moderate to severe psoriasis. Clinical trials results of ixekizumab, brodalumab, secukinumab and bimekizumab have been presented.

EXPERT OPINION

Il-17 inhibitors are a very fast and effective treatment against psoriasis; however, fungal infections can occur during their use, due to IL-17 biological functions. Therefore, it should be mandatory to choose the right patients to treat with these monoclonal antibodies in order to have a tailored target therapy for each patient.

Dimeric translationally controlled tumor protein-binding peptide 2 attenuates imiquimod-induced psoriatic inflammation through induction of regulatory T cells

Psoriasis is a chronic skin inflammation caused by a dysfunctional immune system, which causes systemic inflammation in various organs and tissues. Due to the risk of systemic inflammation and recurrence of psoriasis, it is important to identify the critical targets in the pathogenesis of psoriasis and develop targeted therapeutics. Dimerized translationally controlled tumor protein (dTCTP) promotes immune cell activation as a pro-inflammatory cytokine and plays a role in developing allergic diseases such as asthma and rhinitis. Here, we sought to explore whether dTCTP and its inhibition contributed to the development and control of imiquimod (IMQ)-induced psoriasis. Topical application of IMQ inflamed the skin of the back and ear, increased inflammatory cytokines, and decreased regulatory T cell markers. Interestingly, TCTP was significantly increased in inflamed skin and immune cells such as T cells, B cells, and macrophages after IMQ treatment and was secreted into the serum to undergo dimerization. Extracellular dTCTP treatment selectively suppressed regulatory T (Treg) cells, not other effector T helper (Th) cells, and increased M1 macrophages. Moreover, dTCTP-binding peptide 2 (dTBP2), a dTCTP inhibitor peptide, effectively attenuated the systemic inflammatory responses, including Th17 cell response, and alleviated psoriatic skin inflammation. dTBP2 blocked dTCTP-mediated Treg suppression and stimulated the expression of Treg cell markers in the spleen and inflammatory skin lesions. These results suggest that dTCTP dysregulated immune balance through Treg suppression in psoriatic inflammation and that functional inhibition of dTCTP by dTBP2 maintained immune homeostasis and attenuated inflammatory skin diseases by expanding Treg cells.

Molecular mechanisms of Biyu decoction as treatment for psoriasis: A network pharmacology and molecular docking study

BACKGROUND

The therapeutic effects of a combination of Chinese medicines called Biyu decoction have been clinically verified, although its molecular targets in psoriasis remain unknown.

AIM

To explore the molecular mechanisms of Biyu decoction for psoriasis treatment.

METHODS

In this network pharmacology and molecular docking study, the Traditional Chinese Medicine Systems Pharmacology database was searched for Biyu decoction active ingredients. GeneCards, Online Mendelian Inheritance in Man, PharmGkb, Therapeutic Target Database, and DrugBank databases were searched for psoriasis-related genes. The genes targeted by the decoction’s active ingredient and disease genes were intersected to obtain predictive targets of the drug during psoriasis treatment. Cytoscape 3.8.0 was used to construct a drug component/ target disease network. The The functional protein association networks database and Cytoscape were used to construct a protein-protein interaction network and streamline the core network. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used for pathway enrichment analysis. Molecular docking technology was used to verify the drug component/target disease network.

RESULTS

We screened 117 major active ingredients, including quercetin, kaempferol, naringenin, and acetyl-shikonin, and identified 213 gene targets, such as MAPK3, JUN, FOS, MYC, MAPK8, STAT3, and NFKBIA. Using a molecular docking analysis, the main active ingredients demonstrated good binding to the core targets. The Gene Ontology analysis showed that these ingredients were significantly associated with biological activities, such as transcription factor DNA binding, RNA polymerase II-specific DNA binding of transcription factors, and cytokine receptor binding; responses to lipopolysaccharides, molecules of bacterial origin, and oxidative stress; and were mainly distributed in membrane rafts, microdomains, and regions. The Kyoto Encyclopedia of Genes and Genomes analysis showed that decoction ingredients act on Th17 cell differentiation, tumor necrosis factor and mitogen-activated protein signaling pathways, the interleukin-17 signaling pathway, and the PI3K-Akt signaling pathway.

CONCLUSION

Biyu decoction may be effective against psoriasis through multi-component, multi-target, and multi-channel synergy.

Unmet Medical Needs in Chronic, Non-communicable Inflammatory Skin Diseases

An estimated 20-25% of the population is affected by chronic, non-communicable inflammatory skin diseases. Chronic skin inflammation has many causes. Among the most frequent chronic inflammatory skin diseases are atopic dermatitis, psoriasis, urticaria, lichen planus, and hidradenitis suppurativa, driven by a complex interplay of genetics and environmental factors. Autoimmunity is another important cause of chronic skin inflammation. The autoimmune response may be mainly T cell driven, such as in alopecia areata or vitiligo, or B cell driven in chronic spontaneous urticaria, pemphigus and pemphigoid diseases. Rare causes of chronic skin inflammation are autoinflammatory diseases, or rheumatic diseases, such as cutaneous lupus erythematosus or dermatomyositis. Whilst we have seen a significant improvement in diagnosis and treatment, several challenges remain. Especially for rarer causes of chronic skin inflammation, early diagnosis is often missed because of low awareness and lack of diagnostics. Systemic immunosuppression is the treatment of choice for almost all of these diseases. Adverse events due to immunosuppression, insufficient therapeutic responses and relapses remain a challenge. For atopic dermatitis and psoriasis, a broad spectrum of innovative treatments has been developed. However, treatment responses cannot be predicted so far. Hence, development of (bio)markers allowing selection of specific medications for individual patients is needed. Given the encouraging developments during the past years, we envision that many of these challenges in the diagnosis and treatment of chronic inflammatory skin diseases will be thoroughly addressed in the future.

Break on through: The role of innate immunity and barrier defence in atopic dermatitis and psoriasis

The human skin can be affected by a multitude of diseases including inflammatory conditions such as atopic dermatitis and psoriasis. Here, we describe how skin barrier integrity and immunity become dysregulated during these two most common inflammatory skin conditions. We summarise recent advances made in the field of the skin innate immune system and its interaction with adaptive immunity. We review gene variants associated with atopic dermatitis and psoriasis that affect innate immune mechanisms and skin barrier integrity. Finally, we discuss how current and future therapies may affect innate immune responses and skin barrier integrity in a generalized or more targeted approach in order to ameliorate disease in patients.

A novel personalised treatment approach for psoriasis: anti-VEGF-A therapy

Chronic plaque psoriasis is an inflammatory skin disease in which genetic predisposition along with environmental factors lead to the development of the disease, which affects 2% of the UK’s population and is associated with extracutaneous morbidities and a reduced quality of life. A complex crosstalk between innate and adaptive immunity, the epithelia and the vasculature maintain the inflammatory milieu in psoriasis. Despite the development of promising treatment strategies, mostly targeting the immune system, treatments fail to fulfil every patient’s goals. Vascular endothelial growth factor‐A (VEGF‐A) mediates angiogenesis and is upregulated in the plaques and plasma of patients with psoriasis. Transgenic expression of VEGF‐A in experimental models led to the development of skin lesions that share many psoriasis features. Targeting VEGF‐A in in vivo models of psoriasis‐like inflammation resulted in disease clearance. Anti‐angiogenesis treatments are widely used for cancer and eye disease and there are clinical reports of patients treated with VEGF‐A inhibitors who have experienced Psoriasis Area and Severity Index improvement. Existing psoriasis treatments downregulate VEGF‐A and angiogenesis as part of their therapeutic effect. Pharmacogenetics studies suggest the existence of different genetic signatures within patients with psoriasis that correspond with different treatment responsiveness and disease severity. There is a subset of patients with psoriasis with an increased predisposition to produce high levels of VEGF‐A, who may be most likely to benefit from anti‐VEGF‐A therapy, offering an opportunity to personalize treatment in psoriasis. Anti‐VEGF‐A therapies may offer an alternative to existing anticytokine strategies or be complementary to standard treatments for the management of psoriasis.

Evaluation of Psoriasis Area and Severity Index Thresholds as Proxies for Systemic Inflammation on an Individual Patient Level

BACKGROUND

Psoriasis is a chronic and systemic inflammatory disease with a loss of up to 5 life years, which is thought to be reduced by biologic treatment. Disease severity and eligibility for systemic treatment are often based on the cutaneous psoriasis area and severity index (PASI) with a cut-off of 10 in several European countries. However, it is unclear how well this cut-off reflects systemic inflammation and, consequently, the risk for the development of comorbidity.

OBJECTIVES

(1) To assess whether specific PASI thresholds, in particular PASI 10, predict elevated biomarkers of systemic inflammation and cardiovascular risk on an individual patient level. (2) To assess the association of PASI and psoriatic arthritis with biomarkers of systemic inflammation and cardiovascular risk.

METHODS

Retrospective cross-sectional study of 72 psoriasis patients without systemic treatment.

RESULTS

Overall, 68, 42, and 50% of patients had cardiovascular risk level neutrophil-to-lymphocyte ratio (NLR), C-reactive protein, and elevated platelet-to-lymphocyte ratio (PLR) values, respectively. The respective positive predictive values of PASI 10 were 70, 45, and 70. The performance of the optimal PASI cut-offs according to the Youden index was similarly weak. Subgrouping of patients with a PASI below 10 did not result in a considerably improved reflection of systemic inflammation. PLR was significantly higher in patients with moderate-to-severe compared to mild psoriasis and significantly correlated with PASI in patients with a PASI above 2 (rs = 0.266, n = 64). NLR was significantly higher in patients with psoriatic arthritis.

CONCLUSION

Specific PASI thresholds were not well suited to predict elevated biomarkers of systemic inflammation and cardiovascular risk on an individual patient level. Therefore, PASI, and possibly other purely cutaneous measures, may not be ideal as stand-alone parameters to define disease severity and eligibility for systemic treatment. Our results are relevant for the ongoing discussion on the definition of psoriasis severity and eligibility for systemic treatment. Further research addressing the added value of a set of biomarkers of systemic inflammation in the assessment of psoriasis severity would be desirable.

Interleukin-1 Links Autoimmune and Autoinflammatory Pathophysiology in Mixed-Pattern Psoriasis

Autoinflammatory and autoimmune diseases are characterized by an oversensitive immune system with loss of the physiological endogenous regulation, involving multifactorial self-reactive pathological mechanisms of mono- or polygenic nature. Failure in regulatory mechanisms triggers a complex network of dynamic relationships between innate and adaptive immunity, leading to coexistent autoinflammatory and autoimmune processes. Sustained exposure to a trigger or a genetic alteration at the level of the receptors of the natural immune system may lead to abnormal activation of the innate immune system, adaptive system activation, loss of self-tolerance, and systemic inflammation. The IL-1 family members critically activate and regulate innate and adaptive immune responses' diversity and plasticity in autoimmune and/or autoinflammatory conditions. The IL-23/IL-17 axis is key in the communication between innate immunity (IL-23-producing myeloid cells) and adaptive immunity (Th17- and IL-17-expressing CD8+ T cells). In psoriasis, these cytokines are decisive to the different clinical presentations, whether as plaque psoriasis (psoriasis vulgaris), generalized pustular psoriasis (pustular psoriasis), or mixed forms. These forms reflect a gradient between autoimmune pathophysiology with predominant adaptive immune response and autoinflammatory pathophysiology with predominant innate immune response.

Perfusion measured by laser speckle contrast imaging as a predictor for expansion of psoriasis lesions

Background

Skin microvasculature changes are crucial in psoriasis development and correlate with perfusion. The noninvasive Handheld Perfusion Imager (HAPI) examines microvascular skin perfusion in large body areas using laser speckle contrast imaging (LSCI).

Objectives

To (i) assess whether increased perilesional perfusion and perfusion inhomogeneity are predictors for expansion of psoriasis lesions and (ii) assess feasibility of the HAPI system in a mounted modality.

Methods

In this interventional pilot study in adults with unstable plaque psoriasis, HAPI measurements and color photographs were performed for lesions present on one body region at week 0, 2, 4, 6 and 8. The presence of increased perilesional perfusion and perfusion inhomogeneity was determined. Clinical outcome was categorized as increased, stable or decreased lesion surface between visits. Patient feedback was collected on a 10‐point scale.

Results

In total, 110 lesions with a median follow‐up of 6 (IQR 6.0) weeks were assessed in 6 patients with unstable plaque psoriasis. Perfusion data was matched to 281 clinical outcomes after two weeks. A mixed multinomial logistic regression model revealed a predictive value of perilesional increased perfusion (OR 9.90; p < 0.001) and perfusion inhomogeneity (OR 2.39; p = 0.027) on lesion expansion after two weeks compared to lesion stability. HAPI measurements were considered fast, patient‐friendly and important by patients.

Conclusion

Visualization of increased perilesional perfusion and perfusion inhomogeneity by noninvasive whole field LSCI holds potential for prediction of psoriatic lesion expansion. Furthermore, the HAPI is a feasible and patient‐friendly tool.

Therapeutic Development Based on the Immunopathogenic Mechanisms of Psoriasis

Psoriasis, a complex inflammatory autoimmune skin disorder that affects 2–3% of the global population, is thought to be genetically predetermined and induced by environmental and immunological factors. In the past decades, basic and clinical studies have significantly expanded knowledge on the molecular, cellular, and immunological mechanisms underlying the pathogenesis of psoriasis. Based on these pathogenic mechanisms, the current disease model emphasizes the role of aberrant Th1 and Th17 responses. Th1 and Th17 immune responses are regulated by a complex network of different cytokines, including TNF-α, IL-17, and IL-23; signal transduction pathways downstream to the cytokine receptors; and various activated transcription factors, including NF-κB, interferon regulatory factors (IRFs), and signal transducer and activator of transcriptions (STATs). The biologics developed to specifically target the cytokines have achieved a better efficacy and safety for the systemic management of psoriasis compared with traditional treatments. Nevertheless, the current therapeutics can only alleviate the symptoms; there is still no cure for psoriasis. Therefore, the development of more effective, safe, and affordable therapeutics for psoriasis is important. In this review, we discussed the current trend of therapeutic development for psoriasis based on the recent discoveries in the immune modulation of the inflammatory response in psoriasis.

Modeling Skin Inflammation Using Human In Vitro Models

Skin is made up of an epidermis and, dermis which serve as a barrier against physical and environmental threats. Keratinocytes make up greater than 95% of the epidermis and form different layers based on their level of differentiation. Millions of individuals suffer from skin diseases, which are characterized by significant barrier disruption and inflammation. Investigators previously relied on animal models to investigate inflammatory skin diseases; however, technological advances have enabled the use of physiologically human skin models to investigate the effects of inflammatory mediators on the structure and function of skin cells. In this article, we describe two protocols using keratinocytes to investigate tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) driven skin inflammation as a surrogate for psoriasis, vitiligo, and other autoimmune skin diseases driven by these cytokines. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Preparing a HaCaT keratinocyte culture Basic Protocol 2: 3-Dimensional organotypic skin cultures to assess TNF-α and IFN-γ driven skin inflammation.

Profiles of Innate Immune Cell Infiltration and Related Core Genes in Psoriasis

Psoriasis is an inflammatory skin disease with substantial morbidity. Numerous patients with psoriasis experience recurrence after therapy. The underlying mechanism about psoriasis is still not fully understood. Some evidences suggest that innate immunity may play an unexpected and important role in active severe psoriasis. In this work, the deconvolution algorithm CIBERSORT was conducted to identify the infiltration of innate immune cells and related core genes in psoriatic plaque. Datasets from the Gene Expression Omnibus, including skin samples from 405 psoriasis patients and 91 healthy donors, were downloaded for analysis. Considerable differences of the innate immune cell composition were uncovered between psoriatic plaque and control skin. Results revealed that γδ T cells, resting NK cells, M0 macrophages, M1 macrophages, activated dendritic cells, and neutrophils were significantly increased in psoriatic skin, while resting mast cells and active NK cells were significantly decreased. Moreover, the proportion of M0 macrophages or resting mast cells was found to be associated with disease severity. Spearman correlation analysis suggests that RORC and S100A12 genes were related to disease severity, while genes including S100A12, CLEC4C, IL-19, AIM2, IL-17F, and PPARGC1A were correlated with biologic treatment response. In conclusion, this work displays innate immune status in psoriatic skin and provides novel clues for clinical decisions and mechanism study.

miR-146b correlates with increased disease activity and psoriatic tissue inflammation and promotes keratinocyte proliferation in psoriasis

The present study aimed to investigate the expression of microRNA (miR)-146b in psoriatic tissue and its correlation with psoriasis activity and inflammation. The effect of miR-146b overexpression on keratinocyte proliferation and apoptosis was also explored. The expression of miR-146b in the psoriasis-affected tissue and non-affected tissue of 110 patients was determined via reverse transcription-quantitative (RT-q)PCR. The psoriasis-affected body surface area and psoriasis area severity index (PASI) score were recorded for evaluating disease activity. The expression of various inflammatory cytokines in psoriasis-affected tissue was also detected via RT-qPCR. miR-146b overexpression and control plasmids were constructed and transfected into HaCaT cells in vitro. Subsequently, cell proliferation, apoptosis and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-induced cell apoptosis were determined. The results revealed that the expression of miR-146b was increased in psoriasis-affected tissue compared with that in unaffected tissue. The results obtained from a receiver operating characteristic curve analysis demonstrated that miR-146b levels were able to discriminate between psoriasis-affected tissue and unaffected tissue, with an area under the curve value of 0.781 (95% CI: 0.720-0.843). In addition, miR-146b expression in psoriatic tissue was correlated with an increased PASI score in patients with psoriasis. miR-146b expression in psoriatic tissue was positively correlated with TNF-α, interleukin (IL)-6 and IL-17 mRNA levels. In vitro, miR-146b overexpression enhanced HaCaT cell proliferation and suppressed apoptosis as well as TRAIL-induced apoptosis when compared with that in control-transfected HaCaT cells. In conclusion, miR-146b was positively correlated with disease activity and psoriatic tissue inflammation. Keratinocyte proliferation was also promoted in psoriasis.

The Mediator Role of Body Image-Related Cognitive Fusion in the Relationship between Disease Severity Perception, Acceptance and Psoriasis Disability

Psoriasis is a long-term skin disorder without a cure, whose patients are particularly susceptible to mental health diseases. Using a sample of patients diagnosed with psoriasis, this study aimed to: (1) identify the clinical and positive psychological variables that contribute the most to psoriasis disability and (2) assess the mediator role of body image-related cognitive fusion in the relation between disease severity perception and acceptance and self-compassion, on one hand, and psoriasis disability on the other. This is an initial cross-sectional exploratory study, with 75 patients diagnosed with psoriasis (males 52%; mean age 54.99 ± 13.72) answering a sociodemographic and a clinical questionnaire, the Psoriasis Disability Index (PDI), the Cognitive Fusion Questionnaire-Body Image (CFQ-BI), the Acceptance and Action Questionnaire-II (AAQ-II), and the Self-Compassion Scale (SCS). Descriptive and inferential statistics were used to characterize and assess the measures and the final model used. Through path analysis and a hierarchical multiple linear regression, it was found that the variables that significantly contributed to psoriasis disability were years of education, impact on social life and body image, explaining 70% of the variance. Body image-related cognitive fusion was a significant mediator in the relationship between disease severity and acceptance, and psoriasis disability. The implications of this study are considered to be extremely relevant, since it will allow additional information to be provided to psoriasis patients, appropriated to their educational level, aiming to reduce distorted perceptions of disease severity and intervene in the ability to accept this specific and important chronic health condition.

Enhanced Inflammasome Activity in Patients with Psoriasis Promotes Systemic Inflammation

Psoriasis is linked to systemic inflammation and cardiovascular comorbidities, but studies of the underlying cellular mechanisms are lacking. The NLRP3 inflammasome is genetically associated with psoriasis, and its activation is increasingly linked with cardiovascular disease. In this study, we show that patients with psoriasis exhibited higher plasma levels of inflammasome-generated IL-1β and IL-18, without any correlation to skin lesion severity. Increased constitutive expression of the inflammasome sensors NLRP3, NLRP1, and AIM2 was found in peripheral blood cells of the patients and also of those with mild disease, and this was accompanied by an increased caspase-1 reactivity in the myeloid blood subsets. TNF-α was found to activate selectively the NLRP3 inflammasome without the requirement for a priming signal. TNF-α was found to signal through the TNFR‒caspase-8‒caspase-1 alternative inflammasome pathway, which proceeds independently of pyroptosis. Patients who received anti-TNF therapy had normalized plasma IL-1β and IL-18 levels as well as normalized caspase-1 reactivity. This was in contrast to the patients treated with methotrexate who exhibited persistent, increased caspase-1 reactivity. Thus, we show that the TNF-α-mediated activation of NLRP3 inflammasomes in patients with psoriasis may contribute to systemic inflammation. Anti-TNF therapy normalized inflammasome function, suggesting a mechanism for the cardiovascular risk‒reducing effect.

CARD14E138A signalling in keratinocytes induces TNF-dependent skin and systemic inflammation

To investigate how the CARD14E138A psoriasis-associated mutation induces skin inflammation, a knock-in mouse strain was generated that allows tamoxifen-induced expression of the homologous Card14E138A mutation from the endogenous mouse Card14 locus. Heterozygous expression of CARD14E138A rapidly induced skin acanthosis, immune cell infiltration and expression of psoriasis-associated pro-inflammatory genes. Homozygous expression of CARD14E138A induced more extensive skin inflammation and a severe systemic disease involving infiltration of myeloid cells in multiple organs, temperature reduction, weight loss and organ failure. This severe phenotype resembled acute exacerbations of generalised pustular psoriasis (GPP), a rare form of psoriasis that can be caused by CARD14 mutations in patients. CARD14E138A-induced skin inflammation and systemic disease were independent of adaptive immune cells, ameliorated by blocking TNF and induced by CARD14E138A signalling only in keratinocytes. These results suggest that anti-inflammatory therapies specifically targeting keratinocytes, rather than systemic biologicals, might be effective for GPP treatment early in disease progression.

Cytokines of the IL-17 family in psoriasis

Various immune cells and their messenger substances influence the development of psoriasis. Cytokines of the IL-17 family are of particular importance. In addition to IL-17A, which plays a central role in the pathogenesis of psoriasis, other subtypes of the IL-17 family also have a proinflammatory effect. This review provides an up-to-date overview of the immunopathogenesis of psoriasis with regard to the six IL-17 subtypes, in particular their physiological and pathogenic properties, as well as their significance for psoriasis therapy.

Cyclic enaminone as new chemotype for selective cyclooxygenase-2 inhibitory, anti-inflammatory, and analgesic activities

The cyclic enaminone moiety has been identified as a new scaffold for selective inhibition of cyclooxygenase-2 with anti-inflammatory and analgesic activities. The designed cyclic enaminones have been synthesized conveniently through the development of a new catalyst-free methodology and evaluated for cyclooxygenase (COX-1 and COX-2) inhibitory activities. Three compounds 7d, 8, and 9 predominantly inhibited COX-2 with selectivity index of 74.09, 19.45 and 108.68, respectively, and were assessed for in vivo anti-inflammatory activity in carrageenan induced rat paw edema assay. The anti-inflammatory activity of 7d was comparable to that of celecoxib at a dose of 12.5 mg/kg. However, the compounds 8 and 9 were more/equally effective as anti-inflammatory agent compared to celecoxib at the doses of 12.5 mg/kg and 25 mg/kg and also exhibited anti-inflammatory activity comparable to that of diclofenac. The therapeutic potential of the most active compound 9 was further assessed by performing in vivo thermal and mechanical hyperalgesia tests using various models that revealed its analgesic activity. The in vivo non-ulcerogenicity of 9 revealed the gastrointestinal safety as compared to the non-selective COX inhibitor indomethacin. The in vitro antioxidant activity and in vivo experiments on heart rate and blood pressure provided the cardiovascular safety profile of 9. The molecular docking studies rationalize the COX-2 selectivity of the newly found anti-inflammatory compounds 7d, 8, and 9.

Adaptive and Innate Immunity in Psoriasis and Other Inflammatory Disorders

Over the past three decades, a considerable body of evidence has highlighted T cells as pivotal culprits in the pathogenesis of psoriasis. This includes the association of psoriasis with certain MHC (HLA) alleles, oligoclonal expansion of T cells in some cases, therapeutic response to T cell-directed immunomodulation, the onset of psoriasis following bone marrow transplantation, or induction of psoriasis-like inflammation by T cells in experimental animals. There is accumulating clinical and experimental evidence suggesting that both autoimmune and autoinflammatory mechanisms lie at the core of the disease. Indeed, some studies suggested antigenic functions of structural proteins, and complexes of self-DNA with cathelicidin (LL37) or melanocytic ADAMTSL5 have been proposed more recently as actual auto-antigens in some cases of psoriasis. These findings are accompanied by various immunoregulatory mechanisms, which we increasingly understand and which connect innate and adaptive immunity. Specific adaptive autoimmune responses, together with our current view of psoriasis as a systemic inflammatory disorder, raise the question of whether psoriasis may have connections to autoimmune or autoinflammatory disorders elsewhere in the body. While such associations have been suspected for many years, compelling mechanistic evidence in support of this notion is still scant. This review sets into context the current knowledge about innate and adaptive immunological processes in psoriasis and other autoimmune or autoinflammatory diseases.