Keratin 17 in psoriasis: Current understanding and future perspectives

IL-17C-Mediated Upregulation of SMURF2 Induces Psoriatic Changes in Keratinocytes by Facilitating PPP6C Ubiquitination

Psoriasis, a persistent inflammatory skin condition, affects approximately 2%-3% of the world's population. Increased IL-17C levels are noted in psoriatic lesions, alongside IL-17's ability to diminish protein phosphatase 6 catalytic subunit (PPP6C) expression in keratinocytes. Additionally, SMAD-specific E3 ubiquitin protein ligase 2 (SMURF2) facilitates the degradation of specific substrates through ubiquitination. However, the precise mechanisms of action involving IL-17C, SMURF2, and PPP6C in psoriasis remain unclear. Therefore, this study aims to delve into how IL-17C, SMURF2, and PPP6C contribute to psoriasis development. A psoriasis mice model was established using 5% imiquimod cream. And the expression of IL-17C, SMURF2, and PPP6C was tested. Further, an investigation was conducted using experimental techniques such as CCK-8, flow cytometry, colony formation assay, ELISA, qRT-PCR, western blot assay, co-immunoprecipitation, and ubiquitination assays. Employing both lentiviral transfection and plasmid transfection methods, an in-depth investigation was conducted into the contributions of IL-17C, SMURF2, and PPP6C to psoriasis. The results showed that the IL-17C, Keratin 17 and SMURF2 were increased, and PPP6C was decreased in psoriasis mice model. Further, IL-17C enhanced the cell viability of human epidermal keratinocytes (HaCaT), induced inflammatory responses, and upregulated SMURF2 and Keratin 17 expression. When SMURF2 was silenced, the effects of IL-17C on HaCaT cells were significantly inhibited. Moreover, SMURF2 interacted with PPP6C, promoting its ubiquitination and degradation. Overexpression of SMURF2 further enhanced the effects of IL-17C on HaCaT cells by targeting PPP6C. In conclusion, our study uncovered the upregulation of SMURF2 mediated by IL-17C, leading to psoriasis-like alterations in keratinocytes through the promotion of PPP6C ubiquitination. This novel finding not only provides crucial insights into the molecular mechanisms of psoriasis but also offers potential avenues for innovative therapeutic strategies targeting this mechanism.

The Impacts of Seasonal Factors on Psoriasis

Psoriasis is a chronic inflammatory skin condition driven by immune system dysfunction, genetic predisposition and environmental factors. Patients with psoriasis experience a well-known clinical phenomenon of 'winter severity and summer relief', in which seasonal environmental factors play critical roles in the onset and progression of psoriasis. These factors include temperature, humidity, infection, light exposure and psychological stress. Seasonal changes in temperature and humidity can compromise skin barrier function and exacerbate inflammatory responses, thereby worsening psoriasis symptoms. Notably, during the winter, decreased light exposure leads to reduced vitamin D (VD) levels, reaching their lowest levels from late winter to early spring. This decline in VD levels is associated with increased disease activity, greater disease severity and more frequent flare-ups in patients with psoriasis. During the winter, influenza and Streptococcus pneumoniae infections are more prevalent, which can further exacerbate psoriasis symptoms. Moreover, the environmental conditions in winter can trigger or intensify feelings of depression, which may adversely affect psoriasis through the brain-skin axis. In this comprehensive review, we thoroughly examined the influence of seasonal environmental factors on the incidence, recurrence and severity of psoriasis. By clarifying these complex relationships, we aimed to support the future development of more personalised and effective treatment and management strategies for patients with psoriasis.

The Intersection of Psoriasis and Neoplasia: Risk Factors, Therapeutic Approaches, and Management Strategies

The association between psoriasis and increased cancer risk is gaining recognition as studies reveal shared inflammatory and immune pathways. This review examines the relationship between psoriasis and neoplasia, focusing on cancer risk factors in psoriasis patients, the biological pathways underlying this connection, and the impact of various psoriasis treatments on cancer development. Psoriasis patients have a heightened incidence of certain cancers, such as lymphomas, skin cancers, and urological malignancies, potentially linked to immune dysregulation and chronic inflammation. Immunomodulatory treatments for psoriasis, including conventional systemic therapies and biologics, present varied cancer risks, with others, such as phototherapy, associated with an elevated risk of skin cancers. For oncologic patients with psoriasis, management necessitates a tailored approach, balancing effective psoriasis control with minimizing cancer progression risks. The emergence of IL-17 inhibitors, IL-23 inhibitors, and small-molecule therapies offers promising therapeutic alternatives with favorable safety profiles for these patients. This review underscores the need for interdisciplinary collaboration to optimize care for patients managing both psoriasis and malignancy.

RNAi in psoriasis: A melodic exploration of miRNA, shRNA, and amiRNA with a spotlight on siRNA

Psoriasis (Pso) is an autoimmune inflammatory skin disease characterised by well-demarcated, red plaques covered in silver scales. It affects people of all ages and can be passed down through generations. Genetics play an important role in determining vulnerability to develop Pso. Several large-scale genome-wide association studies have identified over 80 genetic loci associated with Pso susceptibility. Gene expression can be regulated via RNA interference (RNAi). RNAi suppresses gene expression by degrading mRNA molecules. Since its discovery, RNAi has generated considerable excitement over its potential therapeutic benefits. RNAi is mediated by endogenous small RNA molecules like microRNA (miRNA) or exogenous small RNA molecules like small interfering RNA (siRNA), short hairpin RNA (shRNA), and artificial micro RNA (amiRNA). These small RNA molecules can silence a disease-related gene in a sequence-specific manner. Targeting RNAi pathways can help modify disease-related biological processes in various medical conditions, including autoimmune disorders. In Pso, RNAi can downregulate the expression of molecules involved in the pathophysiology of the disease. Significant progress has been made in the field of RNAi therapeutics. However, further research is needed to fine-tune the design and delivery of RNAi therapeutics in humans. In this review, we discuss various effectors of RNAi, some challenges related to RNAi therapeutics (emphasizing siRNA) and strategies to overcome these challenges. Furthermore, we have discussed some studies that employ RNAi therapeutics for Pso.

Tetrastigma hemsleyanum polysaccharides alleviate imiquimod-induced psoriasis-like skin lesions in mice by modulating the JAK/STAT3 signaling pathway

BACKGROUND

The pathogenesis of psoriasis involves the interaction between keratinocytes and immune cells, leading to immune imbalance. While most current clinical treatment regimens offer rapid symptom relief, they often come with significant side effects. Tetrastigma hemsleyanum polysaccharides (THP), which are naturally nontoxic, possess remarkable immunomodulatory and anti-inflammatory properties.

METHODS

In this study, we utilized an imiquimod (IMQ)-induced psoriasis mouse model and a LPS/IL-6-stimulated HaCaT model. The potential and mechanism of action of THP in psoriasis treatment were assessed through methods including Psoriasis Area Severity Index (PASI) scoring, histopathology, flow cytometry, immunoblotting, and reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Percutaneous administration of THP significantly alleviated symptoms and manifestations in IMQ-induced psoriatic mice, including improvements in psoriatic skin appearance (erythema, folds, scales), histopathological changes, decreased PASI scores, and spleen index. Additionally, THP suppressed abnormal proliferation of Th17 cells and excessive proliferation and inflammation of keratinocytes. Furthermore, THP exhibited the ability to regulate the JAK/STAT3 signaling pathway.

CONCLUSION

Findings from in vivo and in vitro studies suggest that THP can inhibit abnormal cell proliferation and excessive inflammation in lesional skin, balance Th17 immune cells, and disrupt the interaction between keratinocytes and Th17 cells. This mechanism of action may involve the modulation of the JAK/STAT3 signaling pathway, offering potential implications for psoriasis treatment.

Keratins 6, 16, and 17 in Health and Disease: A Summary of Recent Findings

Keratins 6, 16, and 17 occupy unique positions within the keratin family. These proteins are not commonly found in the healthy, intact epidermis, but their expression increases in response to damage, inflammation, and hereditary skin conditions, as well as cancerous cell transformations and tumor growth. As a result, there is an active investigation into the potential use of these proteins as biomarkers for different pathologies. Recent studies have revealed the role of these keratins in regulating keratinocyte migration, proliferation, and growth, and more recently, their nuclear functions, including their role in maintaining nuclear structure and responding to DNA damage, have also been identified. This review aims to summarize the latest research on keratins 6, 16, and 17, their regulation in the epidermis, and their potential use as biomarkers in various skin conditions.

Uridine phosphorylase-1 promotes cell viability and cell-cycle progression in human epidermal keratinocytes via the glycolytic pathway

Glycolysis is vital for the excessive proliferation of keratinocytes in psoriasis, and uridine phosphorylase-1 (UPP1) functions as an enhancer of cancer cell proliferation. However, little is known about whether UPP1 promotes keratinocyte proliferation and accelerates psoriasis development. This study revealed that UPP1 facilitates cell viability and cell-cycle progression in human epidermal keratinocytes (HEKs) by modulating the glycolytic pathway. Bioinformatics analysis of UPP1 gene expression and its correlation with the Reactome revealed that UPP1 mRNA expression, cell-cycle progression, the interleukin-6 (IL-6)/Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway and glycolysis were positively associated with psoriasis. Cell proliferation, the cell cycle and glycolysis were evaluated after UPP1 was silenced or overexpressed. The results showed that UPP1 overexpression increased cell proliferation, cell-cycle progression and glycolysis, which was contrary to the effects of UPP1 silencing. However, the STAT3 inhibitor diminished UPP1 expression because STAT3 can bind to the UPP1 promoter. In conclusion, UPP1 was significantly activated by the IL-6/STAT3 pathway and could modulate glycolysis to regulate cell proliferation and cell-cycle progression in keratinocytes during the development of psoriasis.

Reactive oxygen species-responsive supramolecular deucravacitinib self-assembly polymer micelles alleviate psoriatic skin inflammation by reducing mitochondrial oxidative stress

Introduction

The new topical formula is urgent needed to meet clinical needs for majority mild patients with psoriasis. Deucravacitinib exerts outstanding anti-psoriatic capacity as an oral TYK2 inhibitor; however, single therapy is insufficient to target the complicated psoriatic skin, including excessive reactive oxygen species (ROS) and persistent inflammation. To address this need, engineered smart nano-therapeutics hold potential for the topical delivery of deucravacitinib.

Methods

hydrophobic Deucravacitinib was loaded into polyethylene glycol block-polypropylene sulphide (PEG-b-PPS) for transdermal delivery in the treatment of psoriasis. The oxidative stress model of HaCaT psoriasis was established by TNF-α and IL-17A in vitro. JC-1 assay, DCFH-DA staining and mtDNA copy number were utilized to assess mitochondrial function. 0.75% Carbopol®934 was incorporated into SPMs to produce hydrogels and Rhb was labeled to monitor penetration by Immunofluorescence. In vivo, we established IMQ-induced psoriatic model to evaluate therapeutic effect of Car@Deu@PEPS.

Results

Deu@PEPS exerted anti-psoriatic effects by restoring mitochondrial DNA copy number and mitochondrial membrane potential in HaCaT. In vivo, Car@Deu@PEPS supramolecular micelle hydrogels had longer retention time in the dermis in the IMQ-induced ROS microenvironment. Topical application of Car@Deu@PEPS significantly restored the normal epidermal architecture of psoriatic skin with abrogation of splenomegaly in the IMQ-induced psoriatic dermatitis model. Car@Deu@PEPS inhibited STAT3 signaling cascade with a corresponding decrease in the levels of the differentiation and proliferative markers Keratin 17 and Cyclin D1, respectively. Meanwhile, Car@Deu@PEPS alleviated IMQ-induced ROS generation and subsequent NLRP3 inflammasome-mediated pyroptosis.

Conclusion

Deu@PEPS exerts prominent anti-inflammatory and anti-oxidative effects, which may offers a more patient-acceptable therapy with fewer adverse effects compared with oral deucravacitinib.

Rh family C glycoprotein contributes to psoriatic inflammation through regulating the dysdifferentiation and cytokine secretion of keratinocytes

BACKGROUND

Keratinocyte dysdifferentiation and proinflammatory cytokine production play a central role in psoriatic inflammation. According to recent studies, the Rh family C glycoprotein (RHCG) enhances cell proliferation and disrupts cell differentiation. However, the specific role of RHCG psoriasis development remains unclear.

OBJECTIVE

We here explored the effect of RHCG on keratinocytes under psoriatic inflammation.

METHODS

The cell counting kit‑8 assay was conducted to assess proliferation. RHCG protein expression was assessed through western blotting and enzyme-linked immunosorbent assays. The expression of proinflammatory cytokines and differentiation markers was analyzed through a quantitative reverse-transcription polymerase chain reaction.

RESULTS

Both RHCG mRNA and protein levels increased in psoriatic skin. Notably, cultured keratinocytes treated with an M5 cocktail, which mimics psoriatic inflammation, exhibited higher RHCG expression. Furthermore, RHCG overexpression promoted keratinocyte proliferation, accompanied by an increase in the production of interleukin (IL)-1β, IL-6, and IL-8, and tumor necrosis factor-α. RHCG overexpression also resulted in higher expression of keratin 17, a differentiation marker. Conversely, RHCG gene knockdown reduced keratinocyte proliferation and cytokine secretion. RHCG inhibition in cells recovered both keratin 1 and loricrin expression. Additionally, RHCG overexpression facilitated the phosphorylation of nuclear factor-kappa B and extracellular signal-regulated protein kinase signaling pathways. Importantly, when these signaling pathways were inhibited, the effect of RHCG on keratinocytes was attenuated.

CONCLUSION

These findings support the substantial role of RHCG in psoriatic inflammation development and suggest that RHCG serves as a potential target for psoriasis treatment.

Etiopathogenesis of Psoriasis: Integration of Proposed Theories

Psoriasis is a chronic inflammatory disease characterized by squamous and erythematous plaques on the skin and the involvement of the immune system. Global prevalence for psoriasis has been reported around 1-3% with a higher incidence in adults and similar proportions between men and women. The risk factors associated with psoriasis are both extrinsic and intrinsic, out of which a polygenic predisposition is a highlight out of the latter. Psoriasis etiology is not yet fully described, but several hypothesis have been proposed: 1) the autoimmunity hypothesis is based on the over-expression of antimicrobial peptides such as LL-37, the proteins ADAMTSL5, K17, and hsp27, or lipids synthesized by the PLA2G4D enzyme, all of which may serve as autoantigens to promote the differentiation of autoreactive lymphocytes T and unleash a chronic inflammatory response; 2) dysbiosis of skin microbiota hypothesis in psoriasis has gained relevance due to the observations of a loss of diversity and the participation of pathogenic bacteria such as Streptococcus spp. or Staphylococcus spp. the fungi Malassezia spp. or Candida spp. and the virus HPV, HCV, or HIV in psoriatic plaques; 3) the oxidative stress hypothesis, the most recent one, describes that the cell injury and the release of proinflammatory mediators and antimicrobial peptides that leads to activate of the Th1/Th17 axis observed in psoriasis is caused by a higher release of reactive oxygen species and the imbalance between oxidant and antioxidant mechanisms. This review aims to describe the mechanisms involved in the three hypotheses on the etiopathogeneses of psoriasis.

Skin barrier-inflammatory pathway is a driver of the psoriasis-atopic dermatitis transition

As chronic inflammatory conditions driven by immune dysregulation are influenced by genetics and environment factors, psoriasis and atopic dermatitis (AD) have traditionally been considered to be distinct diseases characterized by different T cell responses. Psoriasis, associated with type 17 helper T (Th17)-mediated inflammation, presents as well-defined scaly plaques with minimal pruritus. AD, primarily linked to Th2-mediated inflammation, presents with poorly defined erythema, dry skin, and intense itching. However, psoriasis and AD may overlap or transition into one another spontaneously, independent of biological agent usage. Emerging evidence suggests that defects in skin barrier-related molecules interact with the polarization of T cells, which forms a skin barrier-inflammatory loop with them. This loop contributes to the chronicity of the primary disease or the transition between psoriasis and AD. This review aimed to elucidate the mechanisms underlying skin barrier defects in driving the overlap between psoriasis and AD. In this review, the importance of repairing the skin barrier was underscored, and the significance of tailoring biologic treatments based on individual immune status instead of solely adhering to the treatment guidelines for AD or psoriasis was emphasized.

Fast and slow muscle fiber transcriptome dynamics with lifelong endurance exercise

We investigated fast and slow muscle fiber transcriptome exercise dynamics among three groups of men: lifelong exercisers (LLE, n = 8, 74 ± 1 yr), old healthy nonexercisers (OH, n = 9, 75 ± 1 yr), and young exercisers (YE, n = 8, 25 ± 1 yr). On average, LLE had exercised ∼4 day·wk-1 for ∼8 h·wk-1 over 53 ± 2 years. Muscle biopsies were obtained pre- and 4 h postresistance exercise (3 × 10 knee extensions at 70% 1-RM). Fast and slow fiber size and function were assessed preexercise with fast and slow RNA-seq profiles examined pre- and postexercise. LLE fast fiber size was similar to OH, which was ∼30% smaller than YE (P < 0.05) with contractile function variables among groups, resulting in lower power in LLE (P < 0.05). LLE slow fibers were ∼30% larger and more powerful compared with YE and OH (P < 0.05). At the transcriptome level, fast fibers were more responsive to resistance exercise compared with slow fibers among all three cohorts (P < 0.05). Exercise induced a comprehensive biological response in fast fibers (P < 0.05) including transcription, signaling, skeletal muscle cell differentiation, and metabolism with vast differences among the groups. Fast fibers from YE exhibited a growth and metabolic signature, with LLE being primarily metabolic, and OH showing a strong stress-related response. In slow fibers, only LLE exhibited a biological response to exercise (P < 0.05), which was related to ketone and lipid metabolism. The divergent exercise transcriptome signatures provide novel insight into the molecular regulation in fast and slow fibers with age and exercise and suggest that the ∼5% weekly exercise time commitment of the lifelong exercisers provided a powerful investment for fast and slow muscle fiber metabolic health at the molecular level.NEW & NOTEWORTHY This study provides the first insights into fast and slow muscle fiber transcriptome dynamics with lifelong endurance exercise. The fast fibers were more responsive to exercise with divergent transcriptome signatures among young exercisers (growth and metabolic), lifelong exercisers (metabolic), and old healthy nonexercisers (stress). Only lifelong exercisers had a biological response in slow fibers (metabolic). These data provide novel insights into fast and slow muscle fiber health at the molecular level with age and exercise.

Immune cells in the epithelial immune microenvironment of psoriasis: emerging therapeutic targets

Psoriasis is a chronic autoimmune inflammatory disease characterized by erroneous metabolism of keratinocytes. The development of psoriasis is closely related to abnormal activation and disorders of the immune system. Dysregulated skin protective mechanisms can activate inflammatory pathways within the epithelial immune microenvironment (EIME), leading to the development of autoimmune-related and inflammatory skin diseases. In this review, we initially emphasized the pathogenesis of psoriasis, paying particular attention to the interactions between the abnormal activation of immune cells and the production of cytokines in psoriasis. Subsequently, we delved into the significance of the interactions between EIME and immune cells in the emergence of psoriasis. A thorough understanding of these immune processes is crucial to the development of targeted therapies for psoriasis. Finally, we discussed the potential novel targeted therapies aimed at modulating the EIME in psoriasis. This comprehensive examination sheds light on the intricate underlying immune mechanisms and provides insights into potential therapeutic avenues of immune-mediated inflammatory diseases.

A Route for Investigating Psoriasis: From the Perspective of the Pathological Mechanisms and Therapeutic Strategies of Cancer

Psoriasis is an incurable skin disease that develops in about two-thirds of patients before the age of 40 and requires lifelong treatment; its pathological mechanisms have not been fully elucidated. The core pathological process of psoriasis is epidermal thickening caused by the excessive proliferation of epidermal keratinocytes, which is similar to the key feature of cancer; the malignant proliferation of cancer cells causes tumor enlargement, suggesting that there is a certain degree of commonality between psoriasis and cancer. This article reviews the pathological mechanisms that are common to psoriasis and cancer, including the interaction between cell proliferation and an abnormal immune microenvironment, metabolic reprogramming, and epigenetic reprogramming. In addition, there are common therapeutic agents and drug targets between psoriasis and cancer. Thus, psoriasis and cancer share a common pathological mechanisms-drug targets-therapeutic agents framework. On this basis, it is proposed that investigating psoriasis from a cancer perspective is beneficial to enriching the research strategies related to psoriasis.

Gentiopicroside-Loaded Chitosan Nanoparticles Inhibit TNF-α-Induced Proliferation and Inflammatory Response in HaCaT Keratinocytes and Ameliorate Imiquimod-Induced Dermatitis Lesions in Mice

Purpose

In this study, we aimed to report the biological characteristics of the first successful synthesis of gentiopicroside-loaded chitosan nanoparticles and to evaluate the therapeutic effects and preliminary mechanisms of gentiopicrin-loaded chitosan on psoriasis-like cell and mouse models.

Methods

Gentiopicroside-loaded chitosan nanoparticles (CHI-GEN) were prepared, and their biological characteristics were evaluated. HaCaT keratinocytes were stimulated with TNF-α to establish a psoriatic keratinocyte model. MTT assay and flow cytometry were used to measure cell viability and apoptosis, respectively. mRNA levels of K17, VEGF A, and IL-6 and IL-23A were detected using qRT-PCR. These tests were used to preliminarily assess the effects of CHI-GEN on keratinocyte proliferation and inflammation. Imiquimod was used to construct a psoriasis-like mice model. The severity of psoriasis was scored based on the psoriasis area severity index (PASI), H&E staining was used to observe the histological changes and the level of inflammation and cell proliferation of skin lesions was evaluated by measuring the mRNA levels of K17, IL-23A, and IL-17A using qRT-PCR.

Results

The average particle size of CHI-GEN nanoparticles was approximately 100 nm, and the zeta potential was 2.69 ± 0.87 mV. The cumulative release was 67.2% in solutions of pH 5.5 at 24 h. GEN reduced TNF-α-induced excessive proliferation of HaCaT keratinocytes and downregulated mRNA levels of K17, VEGF A, and inflammatory cytokines IL-6 and IL-23A, which was more obvious in the CHI-GEN treatment group. Additionally, CHI-GEN significantly improved the severity of skin lesions in psoriasis-like mice and downregulated the mRNA expressions of IL-6, IL-23A, and IL-17A in mice skin lesions.

Conclusion

In conclusion, we successfully prepared gentiopicrin-chitosan nanoparticles. Our results show that these nanoparticles have anti-psoriasis activity, inhibits keratinocyte proliferation and improves symptoms in psoriasis model mice and can be used to develop an effective strategy for the treatment of psoriasis.

Current and emerging prospects in the psoriatic treatment

Psoriasis is an autoimmune chronic disorder that causes inflammation and a scaly epidermis. The exact pathogenesis of the disease is not known yet. According to the studies, psoriasis is considered an immune-mediated disease. Until now it is believed that genetic and environmental factors are responsible for the disease. There are many comorbidities associated with psoriasis which increases difficulties as patients in some cases get addicted to drugs, alcohol, and smoking which reduces their quality of life. The patient may face social ignorance or suicidal thoughts which may arise in the patient's mind. Due to the undefined trigger of the disease, the treatment is not fully established but by considering the severe impact of the disease researchers are focusing on novel approaches for successful treatment. which has succeeded to a large extent. Here we review pathogenesis, problems faced by psoriatic patients, the need for the development of new treatments over conventional therapies, and the history of psoriatic treatments. We thoroughly focus on emerging treatments like biologics, biosimilars, and small molecules which are now showing more efficacy and safety than conventional treatments. Also, this review article discusses novel approaches which are now in research such as drug repurposing, treatment by stimulation of the vagus nerve, regulation of microbiota, and autophagy for improving disease conditions.

The mRNA Expression Profile of Psoriatic Lesion Distinct from Non-Lesion

Purpose

Psoriasis is a chronic recurring autoimmune skin disease with a complex etiology and chronic progression; however, its molecular mechanisms remain unclear.

Patients and Methods

We performed transcriptomic analysis to profile the mRNA expression of psoriatic lesions (PL) and non-lesion (NL) tissues from psoriasis patients along with normal skin from healthy donors. RT-qPCR was used to validate the mRNA expression profiles.

Results

A total of 237 differentially expressed genes were screened and identified by RNA sequencing. GO and KEGG analysis indicated that these DEGs were enriched in the PPAR signaling pathway and intermediate filament cytoskeleton. For PPAR signaling pathway, the expression of five genes, including ADIPOQ, AQP7, PLIN1, FABP4 and LPL, were all significantly decreased in psoriatic lesions compared to normal skin by RT-qPCR. There is a clear difference between psoriatic lesions and non-lesion in the expression of ADIPOQ, AQP7 and LPL. For intermediate filament cytoskeleton, including KRT27, KRT25, KRT71, KRT86 and KRT85 were significantly decreased in the psoriasis lesions, showing agreement with the RNA-seq data.

Conclusion

This study revealed a significant difference between the mRNA expression profiles of PL, NL tissue and normal skin.

E3 ubiquitin ligase Trim33 ubiquitylates Annexin A2 to promote NF-κB induced skin inflammation in psoriasis

BACKGROUND

Tripartite motif-containing protein 33, a member of the TRIM E3 ligase family, is shown to be involved in tumorigenesis, cell proliferation and inflammation. Alteration of several TRIM family proteins in psoriatic epidermis has been shown to participate in psoriasis pathogenesis. However, little is known about Trim33 expression and its role in psoriasis.

OBJECTIVES

To examine the expression and biological roles of Trim33 in psoriatic process, with a focus on identifying its novel substrates in psoriatic keratinocytes.

METHODS

Gene expression of Trim33 in biopsies from psoriasis patients compared with healthy volunteers was analysed by quantitative real-time polymerase chain reaction (qPCR) and immunofluorescence (IF). Identification of Trim33 substrates were performed using immunoprecipitation combined with mass spectrometry. Protein expression and localization were assessed by immunoblotting and immunofluorescence. Expression of cytokines was analysed with qPCR.

RESULTS

qPCR and IF analysis revealed increased expression of Trim33 in psoriatic epidermis. Overexpression of Trim33 promoted the expression of psoriasis-related proinflammatory cytokines IL-6, IL-1β and NLRP3 inflammasome. Intriguingly, Trim33 induced lysine 63 (K63)-linked ubiquitination of Annexin A2 (Anxa2), which promoted its interaction with p50/p65 subunits of NF-κB, favoured the retention of p50/p65 in the nucleus and promoted the expression of inflammation-related NF-κB downstream genes.

CONCLUSIONS

Our study highlights the upregulation of Trim33 in psoriatic epidermis and its pivotal role in promoting the inflammation of keratinocytes by Anxa2/NF-κB pathway. Our findings imply that Trim33 might be further explored as potential target for psoriasis treatment.

Meta-Analysis of the Efficacy and Safety of Interleukin-23-Targeted Drugs in the Treatment of Moderate-to-Severe Psoriasis

In this study, our purpose was to systematically evaluate the efficacy and safety of interleukin-23 (IL-23)-targeted drugs in the treatment of moderate-to-severe psoriasis and provide an evidence-based reference for clinical treatment. A computer search of PubMed, EMBASE, Web of Science, Cochrane Library, Chinese Journal Full Text Database, Chinese Science and Technology Journal Database, and Wanfang Database was conducted from the establishment of the database to 2021-09-30. The efficacy of IL-23-targeted drugs (trial group) was compared with placebo (control group) in the treatment of psoriasis; i.e., PASI score improvement of 75% or more (PASI 75, PASI 90, and PASI 100) and the safety of randomized controlled trials (RCTs) were collected. Meta-analysis was performed using Rev Man 5.4.3 statistical software after data extraction for clinical studies that met the inclusion criteria. A total of 9 studies were included, all included studies were large multicenter, randomized, double-blind, placebo-controlled studies, and all used correct randomization methods and were of good quality. Meta-analysis showed that the improvement rates of PASI 75, PASI 90, and PASI 100 in the test group were superior to those in the control group (OR = 70.21 (42.25, 166.66), P < 0.00001), (OR = 78.41 (53.09, 115.79), P < 0.00001), and (OR = 77.10 (38.61, 153.99), P < 0.00001), P < 0.05. However, more adverse effects occurred, and the differences were statistically significant. IL-23-targeted drugs have significantly higher response rates compared to placebo in the treatment of psoriasis, and the safety was acceptable.

Alpha-Linolenic Acid Modulates T Cell Incorporation in a 3D Tissue-Engineered Psoriatic Skin Model

Psoriasis is an autoimmune skin disease with an increased number of leukocytes infiltrating the dermal and epidermal compartments compared with normal skin. N-3 polyunsaturated fatty acids (n-3 PUFAs) are frequently used in the clinic in order to attenuate the symptoms of psoriasis. For psoriatic patients, a supplementation of the diet with alpha-linolenic acid (ALA) reduces the activation of T cell signaling pathways, leading to a significant reduction in inflammatory cytokine secretion. However, the precise mechanism of action of n-3 PUFAs in psoriasis is still not understood. In the present study, we elucidated the bioaction of ALA on the adaptive immune component of psoriasis by using a psoriatic skin model produced with the addition of activated T cells. Healthy and psoriatic skin substitutes were produced according to the self-assembly method, using culture media supplemented with 10 μM of ALA. T cells were isolated from blood samples using a negative selection isolation method. ALA supplementation regulated the hyperproliferation and abnormal cell differentiation of psoriatic keratinocytes stimulated by T cells. Additionally, the exogenous ALA was correctly incorporated into the phospholipids of keratinocytes, which resulted in increased levels of ALA, eicosapentaenoic acid (EPA) and n-3 docosapentaenoic acid (n-3 DPA). The infiltration of T cells into the epidermis was reduced when ALA was added to the culture medium, and significant decreases in the levels of inflammatory cytokines and chemokines such as CXCL1, interleukin-6 (IL-6) and interleukin-8 (IL-8) were consequently measured in psoriatic substitutes supplemented with this n-3 PUFA. Altogether, our results showed that in this psoriatic skin model enriched with T cells, ALA exerted its beneficial effect by decreasing the quantities of inflammatory mediators released by T cells.