MicroRNA profiling of psoriatic skin identifies 11 miRNAs associated with disease severity

The causal effects of inflammatory and autoimmune skin diseases on thyroid diseases: evidence from Mendelian randomization study

Background

To clarify the controversy between inflammatory or autoimmune skin diseases and thyroid diseases, we performed two-sample Mendelian randomization (MR) analyses.

Participants

Genetic data on factors associated with atopic dermatitis (AD, n=40,835), seborrheic dermatitis (SD, n=339,277), acne (n=363,927), rosacea (n=299,421), urticaria (n=374,758), psoriasis (n=373,338), psoriasis vulgaris (n=369,830), systemic lupus erythematosus (SLE, n=14,267), vitiligo (n=353,348), alopecia areata (AA, n=361,822), pemphigus (n=375,929), bullous pemphigoid (BP, n=376,274), systemic sclerosis (SSc, n=376,864), localized scleroderma (LS, n=353,449), hypothyroidism (n=314,995 or n=337,159), and hyperthyroidism (n=281,683 or n=337,159) were derived from genome-wide association summary statistics of European ancestry.

Main measures

The inverse variance weighted method was employed to obtain the causal estimates of inflammatory or autoimmune skin diseases on the risk of thyroid diseases, complemented by MR-Egger, weighted median, and MR-pleiotropy residual sum and outlier (MR-PRESSO).

Key results

AD, SLE, SD, and psoriasis vulgaris were associated with an increased risk of hypothyroidism, whereas BP was associated with a lower risk of hypothyroidism (all with p < 0.05). The multivariable MR analyses showed that AD (OR = 1.053; 95%CI: 1.015-1.092; p = 0.006), SLE (OR = 1.093; 95%CI: 1.059-1.127; p < 0.001), and SD (OR = 1.006; 95%CI: 1.002-1.010; p = 0.006) independently and predominately contributed to the genetic causal effect on hypothyroidism after adjusting for smoking. The results showed no causal effects of inflammatory or autoimmune skin diseases on hyperthyroidism.

Conclusion

The findings showed a causal effect of AD, SLE, SD on hypothyroidism, but further investigations should be conducted to explore the pathogenic mechanisms underlying these relationships.

Genome-wide RNA-seq, DNA methylation and small RNA-seq analysis unraveled complex gene regulatory networks in psoriasis pathogenesis

Psoriasis is a complex inflammatory skin disease characterized by reversible albeit relapsing red scaly plaques in the skin of a patient. In addition to the genetic predisposition, involvement of epigenetic and non-coding RNAs have also been liked with the disease. Nevertheless, any comprehensive study involving transcriptomic, small-RNA and DNA methylation at the genomic level from same patients is lacking. To investigate the complex regulation of molecular pathways in psoriasis, we carried out multi-omics integrative analysis of RNA-sequencing, small RNA-sequencing and DNA methylation profiling from the psoriatic and adjacent normal skin tissues. Our multi-omics analysis identified the genes and biological processes regulated either independently or in combination by DNA methylation and microRNAs. We identified miRNAs that specifically regulated keratinocyte hyper-proliferation, and cell cycle progression and checkpoint signaling in psoriasis. On contrary, DNA methylation was found to be more predominant in regulating immune and inflammatory responses, another causative factor in psoriasis pathogenesis. Many characteristic pathways in psoriasis e.g., Th17 cell differentiation and JAK-STAT signaling, were found to be regulated by both miRNAs and DNA methylation. We carried out functional characterization of a downregulated miRNA hsa-let-7c-5p, predicted to target upregulated genes in psoriasis involved in cell cycle processes, Th17 cell differentiation and JAK-STAT signaling pathways. Overexpression of hsa-let-7c-5p in keratinocytes caused the downregulation of its target genes, resulting in reduced cell proliferation and migration rates, demonstrating potential of miRNAs in regulating psoriasis pathogenesis. In conclusion, our findings identified distinct and shared gene-networks regulated by DNA methylation and miRNAs of a complex disease with reversible phenotype.

Upregulated miR-374a-5p drives psoriasis pathogenesis through WIF1 downregulation and Wnt5a/NF-κB activation

BACKGROUND

Psoriasis is a chronic, inflammatory skin disease. MicroRNAs (miRNAs) are an abundant class of non-coding RNA molecules. Recent studies have shown that multiple miRNAs are abnormally expressed in patients with psoriasis. The upregulation of miR-374a-5p has been associated with psoriasis severity. However, the specific role of miR-374a-5p in the pathogenesis of psoriasis remain unclear.

METHODS

qRT-PCR was employed to validate the expression of miR-374a-5p in psoriatic lesions and in a psoriasis-like cell model constructed using a mixture of M5 (IL-17A, IL-22, OSM, IL-1α, and TNF-α). HaCaT cells were transfected with miR-374a-5p mimic/inhibitor, and assays including EdU, CCK-8, and flow cytometry were conducted to evaluate the effect of miR-374a-5p on cell proliferation. The expression of inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α was verified by qRT-PCR. Bioinformatics analysis and dual-luciferase reporter gene assay were performed to detect the downstream target genes and upstream transcription factors of miR-374a-5p, followed by validation of their expression through qRT-PCR and Western blotting. A psoriasis-like mouse model was established using imiquimod cream topical application. The psoriasis area and severity index scoring, hematoxylin-eosin histology staining, and Ki67 immunohistochemistry were employed to validate the effect of miR-374a-5p on the psoriatic inflammation phenotype after intradermal injection of miR-374a-5p agomir/NC. Additionally, the expression of pathway-related molecules and inflammatory factors such as IL-1β, IL-17a, and TNF-α was verified by immunohistochemistry.

RESULTS

Upregulation of miR-374a-5p was observed in psoriatic lesions and the psoriasis-like cell model. In vitro experiments demonstrated that miR-374a-5p not only promoted the proliferation of HaCaT cells but also upregulated the expression of inflammatory cytokines, including IL-1β, IL-6, IL-8, and TNF-α. Furthermore, miR-374a-5p promoted skin inflammation and epidermal thickening in the Imiquimod-induced psoriasis-like mouse model. Mechanistic studies revealed that miR-374a-5p led to downregulation of WIF1, thereby activating the Wnt5a/NF-κB signaling pathway. The transcription factor p65 encoded by RELA, as a subunit of NF-κB, further upregulated the expression of miR-374a-5p upon activation. This positive feedback loop promoted keratinocyte proliferation and abnormal inflammation, thereby facilitating the development of psoriasis.

CONCLUSION

Our findings elucidate the role of miR-374a-5p upregulation in the pathogenesis of psoriasis through inhibition of WIF1 and activation of the Wnt5a/NF-κB pathway, providing new potential therapeutic targets for psoriasis.

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

BACKGROUND

Psoriasis 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.

METHODS

EVs 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.

RESULTS

We 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.

CONCLUSIONS

We 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.

Serum miRNA profiling identified miRNAs associated with disease severity in psoriasis

Psoriasis vulgaris is a chronic, autoimmune skin disease involving a complex interplay of epidermal keratinocytes, dermal fibroblast and infiltrating immune cells. Differential expressions of miRNAs are observed in psoriasis and the deregulated miRNAs are sometimes associated with disease severity. This study aims to identify miRNAs altered in the serum of psoriasis patients that are associated with the Psoriasis Area and Severity Index (PASI). In order to assess miRNA levels in the serum of psoriasis patients, we selected 24 differentially expressed miRNAs in the psoriatic skin are possibly derived from the skin and immune cells, as well as five miRNAs that are enriched in other tissues. We identified 16 miRNAs that exhibited significantly (p < 0.05) altered levels in the serum of psoriasis patients compared to healthy individuals. Among these, 13 miRNAs showed similar expression pattern in the serum of psoriasis patients as also observed in the psoriatic skin tissues. Ten miRNAs showed an accuracy of greater than 75% in classifying the psoriasis patients from healthy individuals. Further analysis of differential miRNA levels between the low PASI group and the high PASI group identified three miRNAs (miR-147b, miR-3614-5p, and miR-125a-5p) with significantly altered levels between the low severity and the high severity psoriasis patients. Our systematic investigation of skin and immune cell-derived miRNAs in the serum of psoriasis patients revealed alteration in miRNA levels to be associated with disease severity, which may help in monitoring the disease progression and therapeutic response.

Mesoporous silica-based nanocarriers with dual response to pH and ROS for enhanced anti-inflammation therapy of 5-demethylnobiletin against psoriasis-like lesions

Psoriasis is an inflammatory skin disease accompanied with chronic papulosquamous lesions and multiple comorbidities that considerably affect patients' quality of life. In order to develop an enhanced therapeutic strategy for psoriasis, 5-demethylnobiletin (5-DN), a kind of polymethoxyflavones (PMFs) with high anti-inflammatory activity, was delivered in vitro and in vivo by the nanocarrier of mesoporous silica nanoparticles (MSNs) both in the human keratinocytes HaCaT cell line and the mouse model with psoriasis-like lesions. The drug-loaded nanocarrier system (MSNs@5-DN) significantly improved the biocompatibility and bioavailability of 5-DN. Investigations at cell biological, histopathological, and molecular levels revealed the pharmacological mechanism of the drug delivery system, including the inhibition of inflammatory responses by downregulating the proinflammatory cytokine levels of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6). The upregulation of anti‑inflammatory cytokine of transforming growth factor-β1 (TGF-β1) and microRNA-17-5p, a critical regulator of the PTEN/AKT pathway, was also observed. The psoriasis-like lesions were markedly ameliorated in the mouse models treated with MSNs@5-DN. The designed drug-loading system shows an enhanced therapeutic outcome for psoriasis-like lesion compared with free 5-DN. This study revealed the synergistic effect of functionalized MSNs loaded with PMFs on the clinical treatment of human psoriasis.

The PI3K-Akt-mTOR and Associated Signaling Pathways as Molecular Drivers of Immune-Mediated Inflammatory Skin Diseases: Update on Therapeutic Strategy Using Natural and Synthetic Compounds

The dysregulated phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway has been implicated in various immune-mediated inflammatory and hyperproliferative dermatoses such as acne, atopic dermatitis, alopecia, psoriasis, wounds, and vitiligo, and is associated with poor treatment outcomes. Improved comprehension of the consequences of the dysregulated PI3K/Akt/mTOR pathway in patients with inflammatory dermatoses has resulted in the development of novel therapeutic approaches. Nonetheless, more studies are necessary to validate the regulatory role of this pathway and to create more effective preventive and treatment methods for a wide range of inflammatory skin diseases. Several studies have revealed that certain natural products and synthetic compounds can obstruct the expression/activity of PI3K/Akt/mTOR, underscoring their potential in managing common and persistent skin inflammatory disorders. This review summarizes recent advances in understanding the role of the activated PI3K/Akt/mTOR pathway and associated components in immune-mediated inflammatory dermatoses and discusses the potential of bioactive natural products, synthetic scaffolds, and biologic agents in their prevention and treatment. However, further research is necessary to validate the regulatory role of this pathway and develop more effective therapies for inflammatory skin disorders.

Conundrum for Psoriasis and Thyroid Involvement

Strategies concerning thyroid anomalies in patients confirmed with psoriasis, either on clinical level or molecular levels, and their genetic findings remain an open issue. Identification of the exact subgroup of individuals that are candidates to endocrine assessments is also controversial. Our purpose in this work was to overview clinical and pathogenic data concerning psoriasis and thyroid comorbidities from a dual perspective (dermatologic and endocrine). This was a narrative review of English literature between January 2016 and January 2023. We included clinically relevant, original articles with different levels of statistical evidence published on PubMed. We followed four clusters of conditions: thyroid dysfunction, autoimmunity, thyroid cancer, and subacute thyroiditis. A new piece of information in this field was the fact that psoriasis and autoimmune thyroid diseases (ATD) have been shown to be related to the immune-based side effects of modern anticancer drugs-namely, immune checkpoint inhibitors (ICP). Overall, we identified 16 confirmatory studies, but with heterogeneous data. Psoriatic arthritis had a higher risk of positive antithyroperoxidase antibodies (TPOAb) (25%) compared to cutaneous psoriasis or control. There was an increased risk of thyroid dysfunction versus control, and hypothyroidism was the most frequent type of dysfunction (subclinical rather than clinical), among thyroid anomalies correlated with >2-year disease duration, peripheral > axial and polyarticular involvement. With a few exceptions, there was a female predominance. Hormonal imbalance included, most frequently, low thyroxine (T4) and/or triiodothyronine (T3) with normal thyroid stimulating hormone (TSH), followed by high TSH (only one study had higher total T3). The highest ratio of thyroid involvement concerning dermatologic subtypes was 59% for erythrodermic psoriasis. Most studies found no correlation between thyroid anomalies and psoriasis severity. Statistically significant odds ratios were as follows: hypothyroidism: 1.34-1.38; hyperthyroidism: 1.17-1.32 (fewer studies than hypo); ATD: 1.42-2.05; Hashimoto's thyroiditis (HT): 1.47-2.09; Graves' disease: 1.26-1.38 (fewer studies than HT). A total of 8 studies had inconsistent or no correlations, while the lowest rate of thyroid involvement was 8% (uncontrolled studies). Other data included 3 studies on patients with ATD looking for psoriasis, as well as 1 study on psoriasis and thyroid cancer. ICP was shown to potentially exacerbate prior ATD and psoriasis or to induce them both de novo (5 studies). At the case report level, data showed subacute thyroiditis due to biological medication (ustekinumab, adalimumab, infliximab). Thyroid involvement in patients with psoriasis thus remained puzzling. We observed significant data that confirmed a higher risk of identifying positive antibodies and/or thyroid dysfunction, especially hypothyroidism, in these subjects. Awareness will be necessary to improve overall outcomes. The exact profile of individuals diagnosed with psoriasis who should be screened by the endocrinology team is still a matter of debate, in terms of dermatological subtype, disease duration, activity, and other synchronous (especially autoimmune) conditions.

The miR-20a/miR-92b Profile Is Associated with Circulating γδ T-Cell Perturbations in Mild Psoriasis

Psoriasis vulgaris (PV) is an autoinflammatory dermatosis of unknown etiology. Current evidence suggests a pathogenic role of γδT cells, but the growing complexity of this population has made the offending subset difficult to pinpoint. The work on γδTCRint and γδTCRhi subsets, which express intermediate and high levels of γδTCR at their surface, respectively, is particularly scarce, leaving their inner workings in PV essentially unresolved. We have shown here that the γδTCRint/γδTCRhi cell composition and their transcriptom are related to the differential miRNA expression by performing a targeted miRNA and mRNA quantification (RT-qPCR) in multiplexed, flow-sorted γδ blood T cells from healthy controls (n = 14) and patients with PV (n = 13). A significant loss of miR-20a in bulk γδT cells (~fourfold decrease, PV vs. controls) largely mirrored increasing Vδ1-Vδ2- and γδintVδ1-Vδ2- cell densities in the bloodstream, culminating in a relative excess of γδintVδ1-Vδ2- cells for PV. Transcripts encoding DNA-binding factors (ZBTB16), cytokine receptors (IL18R1), and cell adhesion molecules (SELPLG) were depleted in the process, closely tracking miR-20a availability in bulk γδ T-cell RNA. Compared to controls, PV was also associated with enhanced miR-92b expression (~13-fold) in bulk γδT cells that lacked association with the γδT cell composition. The miR-29a and let-7c expressions remained unaltered in case-control comparisons. Overall, our data expand the current landscape of the peripheral γδT cell composition, underlining changes in its mRNA/miRNA transcriptional circuits that may inform PV pathogenesis.

Differential microRNA profiles in elderly males with seborrheic dermatitis

Seborrheic dermatitis (SD) is one of the most common skin diseases characterized by inflammatory symptoms and cell proliferation, which has increased incidence in patients older than 50 years. Although the roles of microRNAs (miRNAs) have been investigated in several diseases, miRNA profiles of patients with SD remain unknown. This study aimed to identify differentially expressed miRNAs (DEMs) in lesions of elderly male patients with SD. We used a microarray-based approach to identify DEMs in lesions compared to those in non-lesions of patients with SD. Furthermore, Gene Ontology and pathway enrichment analysis were performed using bioinformatics tools to elucidate the functional significance of the target mRNAs of DEMs in lesions of patients with SD. Expression levels of two miRNAs-hsa-miR-6831-5p and hsa-miR-7107-5p-were downregulated, whereas those of six miRNAs-hsa-miR-20a-5p, hsa-miR-191-5p, hsa-miR-127-3p, hsa-miR-106b-5p, hsa-miR-342-3p, and hsa-miR-6824-5p-were upregulated. Functions of the SD-related miRNAs were predicted to be significantly associated with typical dermatological pathogenesis, such as cell proliferation, cell cycle, apoptosis, and immune regulation. In summary, SD alters the miRNA profile, and target mRNAs of the DEMs are related to immune responses and cell proliferation, which are the two main processes in SD pathogenesis.

miR-124-3p Delivered Using Exosomes Attenuates the Keratinocyte Response to IL-17A Stimulation in Psoriasis

Methods

NHEKs, HaCaT cells, and HEK 293T cells were treated with IL-17A. CCK-8 assays were performed to detect cell activity, and immunofluorescence staining and Western blotting were performed to detect the protein expression of STAT3. After isolation of exosomes via ultracentrifugation, the contents of miR-124-3p and oxidative stress markers such as superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) in keratinocytes were measured. Subsequently, transcriptomic analysis was performed using RNA-seq. Data were analysed by using the “edgeR” package within R. After verifying the abnormally expressed genes stimulated by IL-17A, a dual luciferase reporter assay was used to determine the interaction between miR-124-3p and STAT3. Finally, BALB/c mice were used to establish a psoriasis model for analysis. The effect of elevated miR-124-3p on the psoriasis mouse model was determined by exosomal delivery of miR-124-3p.

Results

IL-17 intervention enhanced the cell activity of keratinocytes (P < 0.05). miR-124-3p was identified by RNA-seq as one of the differentially expressed miRNAs stimulated by IL-17A. miR-124-3p overexpression induced decreased STAT3 and MDA levels, increased SOD and GSH-Px levels in keratinocytes, and alleviated emergency responses of sclerosis damage (P < 0.05). The dual luciferase reporter assay results confirmed that STAT3 was regulated by miR-124-3p in a targeted manner (P < 0.05). Finally, miR-124-3p delivered by exosomes effectively alleviated the pathological manifestations and oxidative stress responses of psoriatic mice.

Conclusions

miR-124-3p regulates keratinocyte activity via STAT3 in response to IL-17A stimulation. The ectopic expression of miR-124-3p in psoriatic skin reduces IL-17A-induced inflammation and inhibits the STAT3 pathway, thus alleviating the symptoms of psoriasis. The findings of this study suggest that exosomes can be used to therapeutically deliver miR-124-3p to keratinocytes and psoriatic lesions, which may provide novel insight for psoriasis treatment.