Inflammatory loop involving Staphylococcus aureus, IL-36γ, and cathepsin S drives immunity disorders in familial acne inversa keratinocytes.

Acne inversa (AI) is an inflammatory skin disease associated with nicastrin (NCSTN) mutations. Despite the dysregulated bacterial-host immune interactions being an essential event in AI, the interaction between bacteria and keratinocytes in AI pathophysiology remains unclear. In this study, the NCSTN gene was suppressed using short hairpin RNA in HaCaT cells. Using RNA sequencing, real-time polymerase chain reaction, and western blotting, the expression of IL-36 cytokines was analyzed. The impact of Staphylococcus aureus on AI keratinocyte inflammation and underlying regulatory molecules was investigated by exposing the HaCaT cells to S. aureus. By stimulating NCSTN knockdown HaCaT cells with IFN-γ, the expression and regulatory mechanism of Cathepsin S (Cat S), an IL-36γ cleavage and activating protease, were investigated. After NCSTN knockdown, the IL-36α expression increased, and the IL-36Ra expression was downregulated. NCSTN/MEK/ERK impairment-induced Krüppel-like factor 4 (KLF4) up-regulation in concert with S. aureus-induced nuclear factor kappa B elevation acts synergistically to promote IL-36γ production with the subsequent IL-8 activation in HaCaT cells. NCSTN/MEK/ERK impairment was also observed in familial AI lesions. IFN-γ-induced Cat S in keratinocytes was enhanced after NCSTN knockdown. The expression of IFN-II pathway molecules was significantly upregulated in both NCSTN knockdown HaCaT cells and familial AI lesions. The Cat S expression was significantly elevated in the patient's AI lesions. Our findings suggested a synergistic relationship between S. aureus and NCSTN/MAPK/KLF4 axis in IL-36γ-induced familial AI keratinocytes.

Advance in Multi-omics Research Strategies on Cholesterol Metabolism in Psoriasis.

The skin is a complex and dynamic organ where homeostasis is maintained through the intricate interplay between the immune system and metabolism, particularly cholesterol metabolism. Various factors such as cytokines, inflammatory mediators, cholesterol metabolites, and metabolic enzymes play crucial roles in facilitating these interactions. Dysregulation of this delicate balance contributes to the pathogenic pathways of inflammatory skin conditions, notably psoriasis. In this article, we provide an overview of omics biomarkers associated with psoriasis in relation to cholesterol metabolism. We explore multi-omics approaches that reveal the communication between immunometabolism and psoriatic inflammation. Additionally, we summarize the use of multi-omics strategies to uncover the complexities of multifactorial and heterogeneous inflammatory diseases. Finally, we highlight potential future perspectives related to targeted drug therapies and research areas that can advance precise medicine. This review aims to serve as a valuable resource for those investigating the role of cholesterol metabolism in psoriasis.

An atypical case of incontinentia pigmenti with a hypomorphic variant.

Incontinentia pigmenti (IP) is a rare X-linked dominant genodermatosis that affects skin, hair, teeth, eyes and central nervous system. We present the case of a female patient with mild IP caused by a hypomorphic pathogenic variant of the inhibitor of the kappa light polypeptide gene enhancer in B cells, kinase gamma (IKBKG) gene. This is the first report of a female IP patient with the hypomorphic variant, NM_001099856.6: c.1423dup, which is causative of anhidrotic ectodermal dysplasia with immune deficiency in males.

Mitophagy and immune infiltration in vitiligo: evidence from bioinformatics analysis.

Background: Vitiligo is an acquired, autoimmune, depigmented skin disease with unclear pathogenesis. Mitochondrial dysfunction contributes significantly to vitiligo, and mitophagy is vital for removing damaged mitochondria. Herein, using bioinformatic analysis, we sought to determine the possible role of mitophagy-associated genes in vitiligo and immune infiltration. Methods: Microarrays GSE53146 and GSE75819 were used to identify differentially expressed genes (DEGs) in vitiligo. By crossing vitiligo DEGs with mitophagy-related genes, the mitophagy-related DEGs were identified. Functional enrichment and protein-protein intersection (PPI) analyses were conducted. Then, the hub genes were identified using two machine algorithms, and receiver operating characteristic (ROC) curves were generated. Next, the immune infiltration and its connection with hub genes in vitiligo were investigated. Finally, the Regnetwork database and NetworkAnalyst were used to predict the upstream transcriptional factors (TFs), microRNAs (miRNAs), and the protein-compound network. Results: A total of 24 mitophagy-related genes were screened. Then, five mitophagy hub genes (GABARAPL2, SP1, USP8, RELA, and TBC1D17) were identified using two machine learning algorithms, and these genes showed high diagnostic specificity for vitiligo. The PPI network showed that hub genes interacted with each other. The mRNA expression levels of five hub genes were validated in vitiligo lesions by qRT-PCR and were compatible with the bioinformatic results. Compared with controls, the abundance of activated CD4+ T cells, CD8+ T cells, immature dendritic cells and B cells, myeloid-derived suppressor cells (MDSCs), gamma delta T cells, mast cells, regulatory T cells (Tregs), and T helper 2 (Th2) cells was higher. However, the abundance of CD56 bright natural killer (NK) cells, monocytes, and NK cells was lower. Correlation analysis revealed a link between hub genes and immune infiltration. Meanwhile, we predicted the upstream TFs and miRNAs and the target compounds of hub genes. Conclusion: Five hub mitophagy-related genes were identified and correlated with immune infiltration in vitiligo. These findings suggested that mitophagy may promote the development of vitiligo by activating immune infiltration. Our study might enhance our comprehension of the pathogenic mechanism of vitiligo and offer a treatment option for vitiligo.

Multi-Omics Research Strategies for Psoriasis and Atopic Dermatitis.

Psoriasis and atopic dermatitis (AD) are multifactorial and heterogeneous inflammatory skin diseases, while years of research have yielded no cure, and the costs associated with caring for people suffering from psoriasis and AD are a huge burden on society. Integrating several omics datasets will enable coordinate-based simultaneous analysis of hundreds of genes, RNAs, chromatins, proteins, and metabolites in particular cells, revealing networks of links between various molecular levels. In this review, we discuss the latest developments in the fields of genomes, transcriptomics, proteomics, and metabolomics and discuss how they were used to identify biomarkers and understand the main pathogenic mechanisms underlying these diseases. Finally, we outline strategies for achieving multi-omics integration and how integrative omics and systems biology can advance our knowledge of, and ability to treat, psoriasis and AD.

Crosstalk between cholesterol metabolism and psoriatic inflammation.

Psoriasis is a chronic autoinflammatory skin disease associated with multiple comorbidities, with a prevalence ranging from 2 to 3% in the general population. Decades of preclinical and clinical studies have revealed that alterations in cholesterol and lipid metabolism are strongly associated with psoriasis. Cytokines (tumor necrosis factor-α (TNF-α), interleukin (IL)-17), which are important in the pathogenesis of psoriasis, have been shown to affect cholesterol and lipid metabolism. Cholesterol metabolites and metabolic enzymes, on the other hand, influence not only the biofunction of keratinocytes (a primary type of cell in the epidermis) in psoriasis, but also the immune response and inflammation. However, the relationship between cholesterol metabolism and psoriasis has not been thoroughly reviewed. This review mainly focuses on cholesterol metabolism disturbances in psoriasis and their crosstalk with psoriatic inflammation.

Proprotein Convertase Furin Regulates Melanogenesis via the Notch Signaling Pathway.

BACKGROUND: Furin is a calcium-dependent serine protease found in almost all mammals. It plays an important role in embryogenesis, tissue homeostasis, tumors pathogenesis, viral infectious diseases, and neurodegenerative diseases. However, whether furin directly regulates melanin synthesis and transport has rarely been evaluated yet. The present study aimed to investigate furin potential function and mechanisms in melanogenesis. METHODS: Short hairpin RNAs targeting furin gene (sh-furin RNAs) were used to inhibit furin gene expression in human melanoma cell line MNT-1 cells. Then, intracellular melanin content was measured using a sodium hydroxide method. Extracellular melanin content was measured determining cell culture medium absorbance at 450 nm. Levodopa (L-DOPA) oxidation rate was measured to assess the tyrosinase activity. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting (WB) were performed to measure melanogenesis-related genes and Notch pathway-related genes expression levels. Human primary melanocytes (MCs) were extracted from foreskin tissues and were stimulated with a furin inhibitor. Then, the extracellular and intracellular melanin content, tyrosinase activity and molecules related to melanogenesis and the Notch pathway expression were measured in MCs with or without a furin inhibitor. Additionally, morpholino technology was used to inhibit furin in zebrafish. Zebrafish pigmentary phenotypes in the control group and furin inhibition group were observed with a stereo microscope. Then, MCs number in the tail and head of the zebrafish were counted using Image J software (version 1.53t, National Institute of Health, Bethesda, MD, USA). Meanwhile, melanin content, tyrosinase activity, and molecules related to melanogenesis and the Notch pathway expression levels were measured. Subsequently, valproic acid (VPA), a Notch pathway agonist, was used in MNT-1 melanoma cells treated with or without sh-furin lentiviral vectors for rescue experiments. RESULTS: Furin inhibition enhanced intracellular and extracellular melanin content, and cellular tyrosinase activity in MNT-1 cells and MCs. Additionally, furin inhibition increased melanin synthesis-associated and transport-associated proteins expression levels while inhibiting Notch pathway-relevant proteins. After using VPA to activate the Notch pathway in MNT-1 cells transfected with a sh-furin RNA, the biological effects resulting from furin knockdown were reversed. In addition, the results of in vivo experiments using morpholino to knock down furin gene in zebrafish further confirmed that furin knockdown regulated melanogenesis and impaired the Notch pathway. CONCLUSIONS: This study clarified that furin affected the synthesis and transport of melanin via Notch pathway. Notch pathway may be a potential therapeutic target for pigmented skin diseases.

KRT5 mutation regulate melanin metabolism through notch signalling pathway between keratinocytes and melanocytes.

Dowling-Degos disease (DDD) is an autosomal dominant hereditary skin disease characterized by acquired reticular hyperpigmentation in flexural sites, and one of its causative genes is KRT5 gene. But the effect of KRT5, expressed only in keratinocytes, on melanocytes is unclear. Other pathogenic genes of DDD include POFUT1, POGLUT1 and PSENEN genes, which is involved in posttranslational modification of Notch receptor. In this study, we aim to determine the ablation of keratinocyte KRT5 affect melanogenesis in melanocyte through Notch signalling pathway. Here we found that KRT5 downregulation decreased the expression of the Notch ligand in keratinocytes and Notch1 intracellular domain in melanocytes, by establishing two cell models of ablation of KRT5 in keratinocytes based on CRISPR/Cas9 site-directed mutation and lentivirus-mediated shRNA. Treatment of melanocytes with Notch inhibitors had same effects with ablation of KRT5 on increase of TYR and decrease of Fascin1. Activation of Notch signalling reverses the effect of ablation of KRT5 on melanogenesis. Immunohistochemistry of DDD lesions with KRT5 gene mutation confirmed changes in the expression of relevant molecules in Notch signalling. Our research elucidates molecular mechanism of KRT5-Notch signalling pathway in the regulation of melanocytes by keratinocytes, and preliminary reveal the mechanism of DDD pigment abnormality caused by KRT5 mutation. These findings identify potential therapeutic targets of the Notch signalling pathway for the treatment of skin pigment disorders.

Associations between vitamin D receptor gene polymorphisms and chronic spontaneous urticaria in Chinese Han population.

INTRODUCTION: Previous studies found that vitamin D receptor (VDR) TaqI, BsmI, FokI and ApaI gene polymorphisms are associated with several inflammatory diseases. However, the relationship between VDR gene polymorphisms and chronic spontaneous urticaria (CSU) is not clear. AIM: The purpose of our study was to explore the relationship between the polymorphism of VDR and the incidence of chronic spontaneous urticaria in the Chinese Han population. Meanwhile, the vitamin D levels in patients with chronic spontaneous urticaria were also detected and the effects of VDR gene polymorphism on vitamin D levels were detected. MATERIAL AND METHODS: The genotypes of four VDR polymorphisms (TaqI, BsmI, ApaI, and FokI) were studied using allele-specific PCR analysis in 90 CSU patients and 90 healthy controls. RESULTS: Compared to the control group, the mutant allele (C) of FokI were more common in patients with CSU (57.2% vs. 45%, p = 0.020, odds ratio (OR) = 0.612, 95% confidence interval (CI): 0.403-0.928). We found that serum vitamin D levels were significantly lower in CSU patients than in healthy controls (p = 0.023). However, the effect of VDR gene polymorphism on vitamin D levels was not found in patients of CSU. CONCLUSIONS: We first reported the effect of VDR gene FokI (rs2228570) polymorphism on the incidence of chronic spontaneous urticaria in the Chinese Han population.

Successful Treatment of Eczema-Like Mucormycosis in a Child by Combination of Intravenous Drip and Percutaneous Injection Amphotericin B.

We report a case of eczema-like cutaneous mucormycosis caused by Rhizopus arrhizus. A 4-year-old child was presented to our hospital with a history of gradually enlarging papule and plaque in the periumbilical area for nearly 4 years since 2 weeks after his birth, and it has been misdiagnosed as eczema for nearly 3 years. Based on histopathology examination, the fungus culture test and DNA sequencing, it was revealed that R. arrhizus should be the responsible fungus for skin infection. The patient was successfully cured by combination of intravenous drip and percutaneous injection amphotericin B for nearly 3 months, and no recrudescence was seen during a follow-up of 6-month observation.