Hyperproliferation Of Keratinocytes Research Articles

P38 Experimental evidence of ecto-5′-nucleotidase (CD73) modulation in psoriasis-like inflammation

Abstract Introduction and aims Adenosine is an endogenous purine nucleoside that, by binding to adenosine receptors, modulates inflammation and immune responses. Psoriasis is a chronic immune-mediated inflammatory skin disease characterized by keratinocyte hyperproliferation and abnormal differentiation. A2A and A2B adenosine receptors modulate keratinocyte proliferation and their expression was found to be altered in psoriatic epidermis. Ecto-5′-nucleotidase (CD73) is an enzyme that hydrolyses extracellular adenosine monophosphate and represents a key control point for extracellular adenosine accumulation. CD73 is involved in the regulation of local immune response and tissue barrier function. As changes in CD73 expression and activity have been associated with other autoimmune diseases, the aim of this study was to investigate CD73 involvement in skin inflammation using in vitro and in vivo approaches. Methods In vitro experiments were performed on human keratinocyte (HaCaT) cell lines stimulated with tumour necrosis factor-α, interleukin (IL)-17A, IL-6 and IL-1α (10 ng mL−1 each), and in vivo, on the mouse model of imiquimod-induced psoriasis-like inflammation on the right ear, which was also performed on CD73−/− mice and their wildtype counterpart. CD73 expression in cell lysates and ear homogenates were evaluated using Western blot analysis. Results We found that CD73 expression was significantly increased (N = 3 wells, P < 0.05) in cytokine-treated HaCaTs compared with unstimulated cells. In vivo experiments showed increased CD73 expression on psoriatic lesions (P < 0.001, N = 3). In CD73−/− mice, imiquimod-induced lesions were exacerbated compared with the development of lesions in wildtype mice as shown by ear thickness (0.190 ± 0.02 mm, knockout mice vs. 0.138 ± 0.02 mm, wildtype mice; P < 0.05, N = 5), erythema and scaling. Conclusions Our preliminary Results show involvement of CD73 in the development of psoriasis-like inflammation, suggesting that CD73 may represent a new therapeutic target in the treatment of skin diseases. Further investigations are needed to provide an in-depth study of CD73 localization in inflamed skin.

Adult Female Acne: Recent Advances in Pathophysiology and Therapeutic Approaches

Adult Female Acne: Recent Advances in Pathophysiology and Therapeutic Approaches

Impaired autophagy in myeloid cells aggravates psoriasis-like skin inflammation through the IL-1β/CXCL2/neutrophil axis

BackgroundPsoriasis is an inflammatory skin disease characterized by the hyperproliferative epidermal keratinocytes and significant immune cells infiltration, leading to cytokines production such as IL-1β, TNF-α, IL-23, and IL-17. Recent study highlights the critical role of IL-1β in the induction and activation of pathogenic Th17 and IL-17-producing γδ T cells, contributing to psoriasis. However, the mechanism underlying IL-1β dysregulation in psoriasis pathogenesis is unclear. Autophagy regulates IL-1β production and has a pleiotropic effect on inflammatory disorders. Previous studies showed controversial role of autophagy in psoriasis pathogenesis, either pro-inflammatory in autophagy-deficient keratinocyte or anti-inflammatory in pharmacologically autophagy-promoting macrophages. Thus, the direct role of autophagy and its therapeutic potential in psoriasis remains unclear.MethodsWe used myeloid cell-specific autophagy-related gene 7 (Atg7)-deficient mice and determined the effect of autophagy deficiency in myeloid cells on neutrophilia and disease pathogenesis in an imiquimod-induced psoriasis mouse model. We then assessed the pathogenic mechanism focusing on immune cells producing IL-1β and IL-17 along with gene expression profiles associated with psoriasis in mouse model and public database on patients. Moreover, therapeutic potential of IL-1β blocking in such context was assessed.ResultsWe found that autophagy deficiency in myeloid cells exacerbated neutrophilic inflammation and disease pathogenesis in mice with psoriasis. This autophagy-dependent effect was associated with a significant increase in IL-1β production from myeloid cells, particularly macrophages, Cxcl2 expression, and IL-17 A producing T cells including γδ T cells. Supporting this, treatment with systemic IL-1 receptor blocking antibody or topical saccharin, a disaccharide suppressing pro-IL-1β expression, led to the alleviation of neutrophilia and psoriatic skin inflammation linked to autophagy deficiency. The pathophysiological relevance of this finding was supported by dysregulation of autophagy-related genes and their correlation with Th17 cytokines in psoriatic skin lesion from patients with psoriasis.ConclusionsOur results suggest that autophagy dysfunction in myeloid cells, especially macrophages, along with IL-1β dysregulation has a causal role in neutrophilic inflammation and psoriasis pathogenesis.

Sensory neurons increase keratinocyte proliferation through CGRP release in a tissue engineered in vitro model of innervation in psoriasis

Skin denervation has been shown to cause remission of psoriatic lesions in patients, which can reappear if reinnervation occurs. This effect can be induced by the activation of dendritic cells through sensory innervation. However, a direct effect of nerves on the proliferation of keratinocytes involved in the formation of psoriatic plaques has not been investigated. We developed, by tissue engineering, a model of psoriatic skin made of patient skin cells that showed increased keratinocyte proliferation and epidermal thickness compared to healthy controls. When this model was treated with CGRP, a neuropeptide released by sensory neurons, an increased keratinocyte proliferation was observed in the psoriatic skin model, but not in the control. When a sensory nerve network was incorporated in the psoriatic model and treated with capsaicin to induce neuropeptide release, an increase of keratinocyte proliferation was confirmed, which was blocked by a CGRP antagonist while no difference was noticed in the innervated healthy control. We showed that sensory neurons can participate directly to keratinocyte hyperproliferation in the formation of psoriatic lesions through the release of CGRP, independently of the immune system. Our unique tissue-engineered innervated psoriatic skin model could be a valuable tool to better understand the mechanism by which nerves may modulate psoriatic lesion formation in humans. Statement of significanceThis study shows that keratinocytes extracted from patients’ psoriatic skin retain, at least in part, the disease phenotype. Indeed, when combined in a 3D model of tissue-engineered psoriatic skin, keratinocytes exhibited a higher proliferation rate, and produced a thicker epidermis than a healthy skin control. In addition, their hyperproliferation was aggravated by a treatment with CGRP, a neuropeptide released by sensory nerves. In a innervated model of tissue-engineered psoriatic skin, an increase in keratinocyte hyperproliferation was also observed after inducing neurons to release neuropeptides. This effect was prevented by concomitant treatment with an antagonist to CGRP. Thus, this study shows that sensory nerves can directly participate to affect keratinocyte hyperproliferation in psoriasis through CGRP release.

The Immunology of Psoriasis-Current Concepts in Pathogenesis.

Psoriasis is one of the most common inflammatory skin diseases with a chronic, relapsing-remitting course. The last decades of intense research uncovered a pathological network of interactions between immune cells and other types of cells in the pathogenesis of psoriasis. Emerging evidence indicates that dendritic cells, TH17 cells, and keratinocytes constitute a pathogenic triad in psoriasis. Dendritic cells produce TNF-α and IL-23 to promote T cell differentiation toward TH17 cells that produce key psoriatic cytokines IL-17, IFN-γ, and IL-22. Their activity results in skin inflammation and activation and hyperproliferation of keratinocytes. In addition, other cells and signaling pathways are implicated in the pathogenesis of psoriasis, including TH9 cells, TH22 cells, CD8+ cytotoxic cells, neutrophils, γδ T cells, and cytokines and chemokines secreted by them. New insights from high-throughput analysis of lesional skin identified novel signaling pathways and cell populations involved in the pathogenesis. These studies not only expanded our knowledge about the mechanisms of immune response and the pathogenesis of psoriasis but also resulted in a revolution in the clinical management of patients with psoriasis. Thus, understanding the mechanisms of immune response in psoriatic inflammation is crucial for further studies, the development of novel therapeutic strategies, and the clinical management of psoriasis patients. The aim of the review was to comprehensively present the dysregulation of immune response in psoriasis with an emphasis on recent findings. Here, we described the role of immune cells, including T cells, B cells, dendritic cells, neutrophils, monocytes, mast cells, and innate lymphoid cells (ILCs), as well as non-immune cells, including keratinocytes, fibroblasts, endothelial cells, and platelets in the initiation, development, and progression of psoriasis.

Combined untargeted metabolomics and network pharmacology approaches to reveal the therapeutic role of withanolide B in psoriasis

Psoriasis is a refractory inflammatory skin disorder in which keratinocyte hyperproliferation is a crucial pathogenic factor. Up to now, it is commonly acknowledged that psoriasis has a tight connection with metabolic disorders. Withanolides from Datura metel L. (DML) have been proved to possess anti-inflammatory and anti-proliferative properties in multiple diseases including psoriasis. Withanolide B (WB) is one of the abundant molecular components in DML. However, existing experimental studies regarding the potential effects and mechanisms of WB on psoriasis still remain lacking. Present study aimed to integrate network pharmacology and untargeted metabolomics strategies to investigate the therapeutic effects and mechanisms of WB on metabolic disorders in psoriasis. In our study, we observed that WB might effectively improve the symptoms of psoriasis and alleviate the epidermal hyperplasia in imiquimod (IMQ)-induced psoriasis-like mice. Both network pharmacology and untargeted metabolomics results suggested that arachidonic acid metabolism and arginine and proline metabolism pathways were linked to the treatment of psoriasis with WB. Meanwhile, we also found that WB may affect the expression of regulated enzymes 5-lipoxygenase (5-LOX), 12-LOX, ornithine decarboxylase 1 (ODC1) and arginase 1 (ARG1) in the arachidonic acid metabolism and arginine and proline metabolism pathways. In summary, this paper showed the potential metabolic mechanisms of WB against psoriasis and suggested that WB would have greater potential in psoriasis treatment.

The role of FASL gene polymorphism (rs: 763110), its serum level and IL21 level with incidence of psoriasis in Iraqi patients

Psoriasis is a chronic, immune-mediated skin disease with systemic pro-inflammatory can defined by keratinocyte hyper proliferation. FASL gene cell surface death receptor which is important in apoptosis mediated by cytotoxic T cells and natural killer cells. The goals of current study is design to investigate genotyping of the FASL gene (Fas ligand gene) -844 T>C (rs:763110), evaluate its serum level and to estimate level of IL-21correlated with incidence of psoriasis in Iraqi patients. 100 blood samples collected from December 2022 to February 2023, blood samples split into two groups first 50 psoriasis patients (30 males and 20 females) with age range (17-66years) and second group 50 Apparently healthy as control group (24 males 26 females) with age range (20-60 years) visit the Al-Yarmouk Teaching Hospital’s Department of Dermatology in Iraq/Baghdad. (HRM–PCR) Technique was use for the investigation of gene polymorphism of the FASL gene (rs763110). While EIISA technique used to estimate serum level of each FASL gene and IL-21 in serum. The result of FASL gene polymorphism revealed that there are three genotype (TT),(TC),(CC). There was no significant difference, between (TC) and (CC) genotype In the FASLG -844 and between the psoriasis and control groups. Moreover there was correlation between genotyping and serum level for FASL (rs763110) gene in that (TC) genotype serum level show significant different from (CC) genotype serum level with p-value (P≤0.05) as well as the FASL serum level in patient which represent high significantly different between psoriasis patients when compared to the healthy controls with p-value (P≤0.01). While result of IL21 serum level in psoriasis patients revealed high significant different with p-value (P≤0.01) vs healthy control with high significant different in sever psoriatic patient vs mild and healthy control with p value (P≤0.01).

Salvianolic acid A prevents UV-induced skin damage by inhibiting the cGAS-STING pathway

DNA damage resulting from UV irradiation on the skin has been extensively documented in numerous studies. In our prior investigations, we demonstrated that UVB-induced DNA breakage from keratinocytes can activate the cGAS-STING pathway in macrophages. The cGAS-STING signaling pathway serves as the principal effector for detecting and responding to abnormal double-stranded DNA in the cytoplasm. Expanding on our previous findings, we have further validated that STING knockout significantly diminishes UVB-induced skin damage, emphasizing the critical role of cGAS-STING activation in this context. Salvianolic acid A, a principal active constituent of Salvia miltiorrhiza Burge, has been extensively studied for its therapeutic effects in conditions such as coronary heart disease, angina pectoris, and diabetic peripheral neuropathy. However, its effect on cGAS-STING pathway and its ability to alleviate skin damage have not been previously reported. In a co-culture system, supernatant from UVB-treated keratinocytes induced IRF3 activation in macrophages, and this activation was inhibited by salvianolic acid A. Our investigation, employing photodamage and photoaging models, establishes that salvianolic acid A effectively mitigates UV-induced epidermal thickening and collagen degeneration. Treatment with salvianolic acid A significantly reduced skin damage, epidermal thickness increase, and keratinocyte hyperproliferation compared to the untreated photo-damage and photoaging model groups. In summary, salvianolic acid A emerges as a promising candidate for preventing UV-induced skin damage by inhibiting cGAS-STING activation. This research enhances our understanding of the intricate mechanisms underlying skin photodamage and provides a potential avenue for the development of therapeutic interventions.

Ursolic Acid Formulations Effectively Induce Apoptosis and Limit Inflammation in the Psoriasis Models In Vitro.

Psoriasis, a prevalent inflammatory skin disorder affecting a significant percentage of the global population, poses challenges in its management, necessitating the exploration of novel cost-effective and widely accessible therapeutic options. This study investigates the potential of ursolic acid (UA), a triterpenoid known for its anti-inflammatory and pro-apoptotic properties, in addressing psoriasis-related inflammation and keratinocyte hyperproliferation. The research involved in vitro models employing skin and immune cells to assess the effects of UA on psoriasis-associated inflammation. The presented research demonstrates the limiting effects of UA on IL-6 and IL-8 production in response to the inflammatory stimuli and limiting effects on the expression of psoriatic biomarkers S100A7, S100A8, and S100A9. Further, the study reveals promising outcomes, demonstrating UA's ability to mitigate inflammatory responses and hyperproliferation of keratinocytes by the induction of non-inflammatory apoptosis, as well as a lack of the negative influence on other cell types, including immune cells. Considering the limitations of UA's poor solubility, hybrid systems were designed to enhance its bioavailability and developed as hybrid nano-emulsion and bi-gel topical systems to enhance bioavailability and effectiveness of UA. One of them in particular-bi-gel-demonstrated high effectiveness in limiting the pathological response of keratinocytes to pro-psoriatic stimulation; this was even more prominent than with ursolic acid alone. Our results indicate that topical formulations of ursolic acid exhibit desirable anti-inflammatory activity in vitro and may be further employed for topical psoriasis treatment.

Langerhans cells and gamma delta Т-lymphocytes in the pathogenesis of psoriasis

Psoriasis is a frequently occurring inflammatory skin disease. Fundamental research into the pathogenesis of psoriasis has significantly expanded our understanding of skin immunology, which has enabled the introduction of innovative and highly effective therapies. Psoriasis is a largely T-lymphocyte-mediated disease in which activation of innate immune cells and pathogenic T cells leads to inflammation and hyperproliferation of keratinocytes. Langerhans cells like dendritic cells (DCs), which play an important role in the immune system, are mainly distributed in the epidermis. Since human and mouse skin DC subpopulations share common ontogenetic characteristics, we can further investigate the role of DCs in psoriatic inflammation in mice. γδT cells are an unconventional population of T-lymphocytes that play an indispensable role in host defense, immune surveillance, and immune system homeostasis. Although γδT cells constitute only a small fraction of the total T cell pool, emerging evidence suggests that aberrantly activated γδT cells may play a role in the pathogenesis of psoriasis. Dermal γδT cells are the major IL-17-producing cells in the skin that respond to IL-23 stimulation. In addition, γδT cells have characteristics of memory cells that mediate repeated episodes of psoriatic inflammation. This review discusses the mechanisms by which Langerhans cells and γδT cells participate in the pathogenesis of psoriasis.

Qinzhuliangxue mixture ameliorates psoriasis by restraining apoptosis in psoriasis via downregulating the MDA-5 pathway

Ethnopharmacological relevancePsoriasis is characterized by hyperkeratosis that produces the classic silvery scales, and the pathogenesis of psoriasis involves abnormal proliferation of keratinocytes. Emerging evidence supports that apoptosis regulates keratinocyte proliferation and formation of stratum corneum, which maintains the homeostasis of the skin. Qinzhuliangxue mixture (QZLX) is a representative formula for the treatment of psoriasis, which was earliest recorded in the classic Chinese medicine book Xia's Surgery. In our previous clinical studies, QZLX demonstrated 83.33% efficacy with few side effects in the treatment of psoriasis. Furthermore, our published basic research has also proved that the QZLX mixture effectively inhibits the hyperproliferation of keratinocytes, thus exerting therapeutic effects on psoriasis. However, whether QZLX mixture can regulate keratinocytes apoptosis requires further clarification. Objective of the studyTo investigate the mechanism of QZLX in the treatment of psoriasis from the perspective of keratinocyte apoptosis. Materials and methodsFirst, psoriasis-like mice with imiquimod (IMQ)-induced were given QZLX intragastric administration and Psoriasis Area Severity Index (PASI) scores were recored for 11 consecutive days to appraise the efficacy. Then, tissue samples were collected for transcriptome analysis. The DEseq2 method detected significantly differentially expressed genes (DEGs), Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway databases were used to analyze the functions and pathway enrichment of DEGs. After that, the therapeutic mechanisms of QZLX in intervening with psoriasis were explored using TUNEL, immunohistochemical staining, and western blotting. ResultsQZLX ameliorated the symptoms and pathological characteristics of IMQ-induced psoriasis in mice. The epidermal cell hyperplasia in the skin was inhibited, in accordance with the suppressed expression of PCNA and Ki67 after treatment. Transcriptome sequencing showed that melanoma differentiation associated gene-5 (MDA-5) was downregulated. GO and KEGG enrichment analysis of the signaling pathways indicated that the differentially expressed genes were significantly enriched in apoptosis pathways. Besides, QZLX treatment decreased the apoptosis of keratinocyte as shown by reduced TUNEL-positive cells. As MDA-5 protein levels decreased, so did the expression of the downstream protein Caspase-8, which indicates that the apoptotic pathway was triggered. Furthermore, QZLX therapy might also help to balance the apoptotic Bcl-2 family expression. ConclusionQZLX restrains the apoptosis of keratinocyte in psoriasis-like mice by downregulating the MDA-5 pathway. The restoration of the balance between cell apoptosis and proliferation in the skin may lead to considerable psoriasis relief. Our study reveals the possible molecular processes behind the effects of QZLX therapy on the skin lesions of psoriasis, and lends support to its clinical efficacy.

Radiation Dermatitis: Radiation-Induced Effects on the Structural and Immunological Barrier Function of the Epidermis.

An important hallmark of radiation dermatitis is the impairment of the mitotic ability of the stem/progenitor cells in the basal cell layers due to radiation-induced DNA damage, leading to suppressed cell renewal in the epidermis. However, this mechanism alone does not adequately explain the complex pathogenesis of radiation-induced skin injury. In this review, we summarize the latest findings on the complex pathogenesis of radiation dermatitis and correlate these with the clinical features of radiation-induced skin reactions. The current studies show that skin exposure to ionizing radiation induces cellular senescence in the epidermal keratinocytes. As part of their epithelial stress response, these senescent keratinocytes secrete pro-inflammatory mediators, thereby triggering skin inflammation. Keratinocyte-derived cytokines and chemokines modulate intercellular communication with the immune cells, activating skin-resident and recruiting skin-infiltrating immune cells within the epidermis and dermis, thereby orchestrating the inflammatory response to radiation-induced tissue damage. The increased expression of specific chemoattractant chemokines leads to increased recruitment of neutrophils into the irradiated skin, where they release cytotoxic granules that are responsible for the exacerbation of an inflammatory state. Moreover, the importance of IL-17-expressing γδ-T cells to the radiation-induced hyperproliferation of keratinocytes was demonstrated, leading to reactive hyperplasia of the epidermis. Radiation-induced, reactive hyperproliferation of the keratinocytes disturbs the fine-tuned keratinization and cornification processes, leading to structural dysfunction of the epidermal barrier. In summary, in response to ionizing radiation, epidermal keratinocytes have important structural and immunoregulatory barrier functions in the skin, coordinating interacting immune responses to eliminate radiation-induced damage and to initiate the healing process.

Keratinocyte-derived circulating microRNAs in extracellular vesicles: a novel biomarker of psoriasis severity and potential therapeutic target

BackgroundPsoriasis is a chronic inflammatory disorder characterized by pathogenic hyperproliferation of keratinocytes and immune dysregulation. Currently, objective evaluation tools reflecting the severity of psoriasis are insufficient. MicroRNAs in extracellular vesicles (EV miRNAs) have been shown to be potential biomarkers for various inflammatory diseases. Our objective was to investigate the possibility of plasma-derived EV miRNAs as a marker for the psoriasis disease severity.MethodsEVs were extracted from the plasma of 63 patients with psoriasis and 12 with Behçet’s disease. We performed next-generation sequencing of the plasma-derived EV miRNAs from the psoriasis patients. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to validate the level of EV miRNA expression. In situ hybridization was used to discern the anatomical location of miRNAs. qRT-PCR, western blotting, and cell counting kits (CCKs) were used to investigate IGF-1 signaling in cells transfected with miRNA mimics.ResultsWe identified 19 differentially expressed EV miRNAs and validated the top three up-and down-regulated EV miRNAs. Among these, miR-625-3p was significantly increased in patients with severe psoriasis in both plasma and skin and most accurately distinguished moderate-to-severe psoriasis from mild-to-moderate psoriasis. It was produced and secreted by keratinocytes upon stimulation. We also observed a significant intensification of IGF-1 signalling and increased cell numbers in the miR-625-3p mimic transfected cells.ConclusionsWe propose keratinocyte-derived EV miR-625-3p as a novel and reliable biomarker for estimating the severity of psoriasis. This biomarker could objectively evaluate the severity of psoriasis in the clinical setting and might serve as a potential therapeutic target.Trial registration None.

Dendrobium officinale Polysaccharide (DOP) inhibits cell hyperproliferation, inflammation and oxidative stress to improve keratinocyte psoriasis-like state

PurposePsoriasis is a skin disease characterized by excessive proliferation, inflammation and oxidative stress in keratinocytes. The present study aimed to investigate the therapeutic effects of Dendrobium officinale polysaccharide (DOP) on keratinocyte psoriasis-like models. MethodsThe HaCaT keratinocyte inflammation models were induced by interleukin (IL)-22 or lipopolysaccharide (LPS), respectively, and oxidative stress damage within cells was elicited by H2O2 and treated using DOP. CCK-8 and EdU were carried out to detect cell proliferation. ELISA, qRT-PCR, and Western blot were conducted to measure the expression of pro-inflammatory cytokines IL17A, IL-23, IL1β, tumor necrosis factor alpha (TNF-α), and IL-6. Reactive oxygen species (ROS) level in keratinocytes was detected by flow cytometry. Cell proliferation-associated proteins (PCNA, Ki67, Cyclin D1) and pathway proteins (p-AKT and AKT), and oxidative stress marker proteins (Nrf-2, CAT, SOD1) were detected by Western blot. ResultDOP did not affect the proliferation of normal keratinocytes, but DOP was able to inhibit the proliferative activity of IL-22-induced overproliferating keratinocytes and suppress the expression of proliferation-related factors PCNA, Ki67, and Cyclin D1 as well as the proliferation pathway p-AKT. In addition, DOP treatment was able to inhibit IL-22 and LPS-induced inflammation and H2O2-induced oxidative stress, including the expression of IL17A, IL-23, IL1β, TNF-α, IL-6, and IL1β, as well as the expression levels of intracellular ROS levels and cellular oxidative stress-related indicators SOD, MDA, CAT, Nrf-2 and SOD1. ConclusionDOP inhibits keratinocyte hyperproliferation, inflammation and oxidative stress to improve the keratinocyte psoriasis-like state.

Identifying the genetic associations among the psoriasis patients in eastern India.

Psoriasis is a multifactorial genetic disorder manifested by hyperproliferation and abnormal differentiation of epidermal keratinocytes, along with the infiltration of inflammatory cells into the skin. Although ~80 genetic susceptibility variants were reported in psoriasis, many loci showed population-specific associations, warranting the need for more population-specific association studies in psoriasis. We determined the association of forty single nucleotide polymorphisms (SNPs) among 2136 psoriasis patients and normal individuals from eastern India. We investigated the expression of corresponding genes and evaluated the protein structure stability for the genes with susceptible coding variants. We found fifteen SNPs significantly associated with psoriasis, while additional three SNPs showed significant association when we classified the patients based on the presence of HLA-Cw6 allele. Epistatic interaction between HLA-Cw6 and other associated loci showed significant association with the SNPs at PSORS1 region, along with other five SNPs outside PSORS1. Three genes showed significant differential expression in psoriatic tissues compared to the adjacent normal skin tissues but were not differential when classified the patients based on their genotypes. SNP rs495337 at SPATA2 (Spermatogenesis Associated 2) showed a 1.2-fold increased risk among the HLA-Cw6 patients compared to combined samples. We found significant downregulation of SPATA2 among the patients with risk genotypes and HLA-Cw6 allele compared to the non-risk genotypes. Protein structure stability analysis showed reduced structural stability for all the mutant residues caused by the associated coding variants. Our study evaluated the genetic associations of psoriasis-susceptible variants in India and evaluated the possible functional significance of these associated variants in psoriasis.

Statement of Retraction: Dihydroartemisinin targets fibroblast growth factor receptor 1 (FGFR1) to inhibit interleukin 17A (IL-17A)-induced hyperproliferation and inflammation of keratinocytes

Statement of Retraction: Dihydroartemisinin targets fibroblast growth factor receptor 1 (FGFR1) to inhibit interleukin 17A (IL-17A)-induced hyperproliferation and inflammation of keratinocytes

FOSL1 regulates hyperproliferation and NLRP3-mediated inflammation of psoriatic keratinocytes through the NF-kB signaling via transcriptionally activating TRAF3

Psoriasis is a common and immune-mediated skin disease related to keratinocytes hyperproliferation and inflammation. Fos-like antigen-1 (FOSL1) is an important transcription factor involved in various diseases. FOSL1 has been reported to be differentially expressed in psoriasis. However, the roles and mechanism of FOSL1 in psoriasis progression remain largely unknown. FOSL1 is an upregulated transcription factor in psoriasis and increased in M5-treated HaCaT cells. FOSL1 had a diagnostic value in psoriasis, and positively associated with PASI score, TNF-α and IL-6 levels in psoriasis patients. FOSL1 silencing attenuated M5-induced HaCaT cell hyperproliferation through decreasing cell viability and proliferative ability and increasing cell apoptosis. FOSL1 knockdown mitigated M5-induced NLRP3 inflammasome activation and it-mediated inflammatory cytokine (IL-6, IL-8 and CCL17) expression. TRAF3 expression was increased in psoriasis patients and M5-treated HaCaT cells. FOSL1 transcriptionally activating TRAF3 in HaCaT cells. TRAF3 overexpression reversed the suppressive effects of FOSL1 silencing on M5-induced hyperproliferation and NLRP3-mediated inflammation. FOSL1 knockdown attenuated M5-induced NF-κB signaling activation by reducing TRAF3. Activation of NF-κB signaling reversed the effects of FOSL1 knockdown on hyperproliferation and inflammation in M5-treated cells. FOSL1 silencing prevented M5-induced hyperproliferation and NLRP3-mediated inflammation of keratinocytes by inhibiting TRAF3-mediated NF-κB activity, indicating FOSL1 might act as a therapeutic target of psoriasis.

Neuropeptide substance P alters stem cell fate to aid wound healing and promote epidermal stratification through asymmetric stem cell divisions.

Loss of sensory innervation delays wound healing and administration of the neuropeptide substance P improves re-epithelialization. Keratinocyte hyperproliferation post-wounding may result from symmetric stem cell (SC) self-renewal, asymmetric SC self-renewal, committed progenitor divisions, or a combination of these. However, the effects of sensory denervation and of neuropeptides on SC proliferation are not known. Here we show that early after wounding both asymmetric and symmetric SC self-renewal increase, without significant committed progenitor (CP) activation. Decreased sensory innervation is associated with a decrease in both SC and CP proliferation. Based on previous work showing that substance P is decreased in capsaicin-treated mice and improves wound healing in normal skin, we examined the effects of substance P on SC and CP proliferation during wound healing. Substance P restored asymmetric SC proliferation in skin with decreased sensory innervation, both at baseline and following wounding. Epidermis with decreased sensory innervation was severely thinned. Consistent with this, substance P-induced asymmetric SC proliferation resulted in increased stratification in skin with both normal and decreased innervation. Lapatinib prevented the substance P-induced increase in asymmetric SC divisions in murine epidermis, as well as the increase in epidermal stratification, suggesting that asymmetric SC divisions are required for epidermal stratification.

Tanshinone IIA, a component of the self-made Xiao-Yin decoction, ameliorates psoriasis by inhibiting IL-17/IL-23 and PTGS2/NF-κB/AP-1 pathways.

Psoriasis is a persistent inflammatory dermatological disorder. Tanshinone IIA (tan-IIA) is a biologically active compound in the self-made Xiao-Yin decoction (SMXYD) and exhibits diverse biological properties, such as anti-proliferative and anti-inflammatory effects. The objective of this investigation was to assess the potential of tan-IIA as a therapeutic agent against psoriasis. Network pharmacology was employed to ascertain the active constituents and potential pathways associated with SMXYD and psoriasis. We conducted CCK-8, qRT-PCR, and western blotting to assess the proliferation of HaCaT keratinocytes and the expression of IL-17/IL-23 and PTGS2/NF-κB/AP-1 pathways. Additionally, we used H&E staining, western blotting, and ELISA to evaluate the therapeutic effects and signaling pathways of tan-IIA in psoriasis-like mice induced by imiquimod (IMQ). Network pharmacology analysis identified eight hub compounds. The Th17/IL-17 signaling was found to be a potential therapeutic pathway of SMXYD against psoriasis, with JUN (AP-1) as the core molecule. Next, PTGS2 was selected as the target of tan-IIA against psoriasis using network pharmacology analysis. Molecular docking showed a high affinity between PTGS2 and tan-IIA. Tan-IIA treatment attenuated M-5-induced hyperproliferation and inflammation in HaCaT keratinocytes. Additionally, Tan-IIA downregulated the PTGS2/NF-κB/AP-1 pathway in HaCaT keratinocytes. In the IMQ-induced psoriasis-like mouse, tan-IIA significantly reduced the severity of skin lesions and downregulated the PTGS2/NF-κB/AP-1 pathway. Moreover, the combination of methotrexate (MTX) and tan-IIA further inhibited the IL-17/IL-23 and PTGS2/NF-κB/AP-1 pathways. The administration of tan-IIA has shown a positive effect on psoriasis by inhibiting the IL-17/IL-23 and PTGS2/NF-κB/AP-1 pathways. The findings suggest that it has promising qualities that make it a potential candidate for the development of future anti-psoriatic agents.

Cycloastragenol restrains keratinocyte hyperproliferation by promoting autophagy via the miR-145/STC1/Notch1 axis in psoriasis

Background Psoriasis is characterized by inflammation and hyperproliferation of epidermal keratinocytes. Cycloastragenol (CAG) is an active molecule of Astragalus membranaceus that potentially plays a repressive role in psoriasis. Activated cell autophagy is an effective pathway for alleviating psoriasis progression. Thus, we investigated the role of CAG in the proliferation and autophagy of interleukin (IL)-22-stimulated keratinocytes. Methods A psoriasis model was established by stimulating HaCaT cells with IL-22. Gene or protein expression levels were measured by qRT-PCR or western blot. Autophagy flux was observed with mRFP-GFP-LC3 adenovirus transfection assay under confocal microscopy. Stanniocalcin-1 (STC1) secretion levels were determined using ELISA kits. The apoptosis rate was assessed using flow cytometry. Interactions between miR-145 and STC1 or STC1 and Notch1 were validated by luciferase reporter gene assays, RIP, and Co-IP assays. Results CAG repressed cell proliferation and promoted apoptosis and autophagy in IL-22-stimulated HaCaT cells. Additionally, CAG promoted autophagy by enhancing miR-145. STC1 silencing ameliorated autophagy repression in IL-22-treated HaCaT cells. Moreover, miR-145 negatively regulated STC1, and STC1 was found to activate Notch1. Lastly, STC1 overexpression reversed CAG-promoted autophagy. Conclusion CAG alleviated keratinocyte hyperproliferation through autophagy enhancement via regulating the miR-145/STC1/Notch1 axis in psoriasis.