Inflammation modulates intercellular adhesion and mechanotransduction in human epidermis via ROCK2
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ABSTRACT: The cytoskeletal mechanisms regulating inflammatory responses in the epidermis are not well described. Here we addressed this question by inducing a psoriatic phenotype in human keratinocytes and reconstructed human epidermis using a cytokine stimulation model.We report the results from RNA-seq in N/TERT keratinocytes treated with M5 or both M5 and ROCK2 inhibitor KD025.
Project description:Aberrant mechanotransduction and compromised epithelial barrier function are associated with numerous human pathologies including inflammatory skin disorders. However, the cytoskeletal mechanisms regulating inflammatory responses in the epidermis are not well understood. Here we addressed this question by inducing a psoriatic phenotype in human keratinocytes and reconstructed human epidermis using a cytokine stimulation model. We show that the inflammation upregulates the Rho-myosin II pathway and destabilizes adherens junctions (AJs) promoting YAP nuclear entry. The integrity of cell-cell adhesion but not the myosin II contractility per se is the determinative factor for the YAP regulation in epidermal keratinocytes. The inflammation-induced disruption of AJs, increased paracellular permeability, and YAP nuclear translocation are regulated by ROCK2, independently from myosin II activation. Using a specific inhibitor KD025, we show that ROCK2 executes its effects via cytoskeletal and transcription-dependent mechanisms to shape the inflammatory response in the epidermis.
Project description:We performed microarray analysis on laser-microdissected epidermis from healthy volunteers and psoriatic patients to identify genes dysregulated in lesional psoriatic epidermis
Project description:We performed microarray analysis on laser-microdissected epidermis from healthy volunteers and psoriatic patients to identify genes dysregulated in lesional psoriatic epidermis
Project description:Background: Cholesterol is de novo synthesized in the upper epidermis and plays an important role in maintaining the normality of skin. Studying the impact of the inhibition of cholesterol de novo synthesis in the epidermis may help understand how skin homeostasis is regulated. Objective: In this study, we created a gene expression profile to investigate the effect of hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors on epidermal homeostasis. Methods: A microarray analysis was performed using normal keratinocytes with or without HMG-CoA reductase inhibitor (pitavastatin) treatment. Real-time PCR confirmed the reproducibility of genes with altered expression in keratinocytes treated with HMG-CoA reductase inhibitors. Among these genes, we focused on reduced expression of claudin 7 histologically confirmed by immunohistochemical staining, in situ hybridization, and immunoelectron microscopy. Results: Claudin-7 was highly expressed in the stratum granulosum of psoriatic lesions but was not expressed in the normal epidermis. Immunoelectron microscopy revealed that claudin-7 was localized in the keratohyalin granules of psoriatic lesions. Conclusion: These results indicate that claudin-7 expression was regulated by HMG-CoA reductase in the epidermis and might play a pathogenic role in the keratohyalin granules found in the epidermal granular layer of psoriasis.
Project description:The study focuses on the cellular composition of the psoriasis epidermis, using single-cell transcriptomics to identify cell subsets and their interactions in both healthy and psoriatic skin. The research uncovers three keratinocyte populations and seven immune cell subsets exclusive to psoriatic lesions. A significant finding is the identification of a previously undetected population of plasmacytoid dendritic cells (pDCs) in the psoriatic epidermis, suggesting their role in the disease's pathogenesis. The study also highlights enhanced keratinocyte-immune cell interactions in psoriatic lesions, contributing to our understanding of psoriasis at the cellular level.
Project description:The aim of the study was to investigate the differential methylation in psoriatic lesional epidermis compared to non-lesional or healthy epidermis.
Project description:Atopic Dermatitis (AD) is the most common inflammatory skin disease and characterized by a deficient epidermal barrier and cutaneous inflammation. Genetic studies suggest a key role of keratinocytes in AD pathogenesis, but the alterations in the proteome that occur in the entire epidermis have not been defined. Employing a pressure-cycling technology-data-independent acquisition (PCT-DIA) approach, we performed quantitative proteomics of epidermis from healthy volunteers and lesional and non-lesional skin of AD patients. Results were validated by targeted proteomics using parallel reaction monitoring mass spectrometry or by immunofluorescence staining. The identified proteins reflect the strong inflammation in lesional skin and the defect in keratinocyte differentiation and epidermal stratification. Most importantly, they reveal impaired activation of the NRF2-antioxidant pathway and reduced abundance of mitochondrial proteins involved in key metabolic pathways in the epidermis. These results provide insight into the molecular alterations in the epidermis of AD patients and identify novel targets for pharmaceutical intervention.
Project description:SAGE libraries from cultured, differentiated keratinocytes and human epidermis, both normal and affected by actinic keratosis Keywords = Keratinocyte, Epidermis, Homo sapiens, Actinic Keratosis, TNF alpha