Project description:Psoriasis is a chronic inflammatory skin disorder that is predominantly characterized by sharply demarcated chronic erythematous plaques. Although its etiological mechanisms are largely unknown, recent evidence suggests that the topical application of imiquimod (IMQ) cream causes psoriasis-like skin inflammation in humans and mice. Skin examined 4 hours after IMQ cream treatment. Results provide insight into the role of each knockout mice phenotype in the response to IMQ-induced psoriasis model.
Project description:The mechanisms underlying pruritus of imiquimod (IMQ)-induced psoriasis remain poorly understood. In this study, we investigated whether there are certain key signaling molecules downstream of the recently identified peptides mediating itch in the spinal cord. We investigated the changes in the trascriptome by performing RNAseq of cervical spinal cords in control and IMQ-induced psoriasis. Our study represents the detailed analysis of transcriptomes of spinal cord in chronic itch model with biologic replicates, generated by RNA-seq technology.
Project description:We provide a new psoriasis mouse model which is induced by p38 activation in skin. We compared the individual transcriptomic profiles of anisomycin and imiquimod-induced dermatitis. We used microarrays to compare the gene expression pattern between anisomycin- and imiquimod- induced dermatitis.
Project description:The polyphenol resveratrol has anti-inflammatory effects in various cells, tissues, animals and human settings of low-grade inflammation. Psoriasis is a disease of both localized and systemic low-grade inflammation. The Sirtuin1 enzyme thought to mediate the effects of resveratrol is present in skin and resveratrol is known to downregulate NF-κB; a major contributor in the development of psoriasis. Consequently we investigated whether resveratrol has an effect on an Imiquimod induced psoriasis-like skin inflammation in mice and sought to identify candidate genes, pathways and interleukins mediating the observed effects. The study consisted of three treatment groups: A control group, an Imiquimod group and an Imiquimod+resveratrol group. Psoriasis severity was assessed using elements of the Psoriasis Area Severity Index, actual skin thickness measurements, and histological examination. We performed an RNA microarray from lesional skin and afterwards Ingenuity pathway analysis to identify affected signalling pathways. Our microarray was compared to a previously deposited microarray to determine if gene changes were psoriasis-like, and to a human microarray to determine if findings could be relevant in a human setting. Imiquimod treatment induced a psoriasis-like skin inflammation. Resveratrol significantly diminished the severity of the psoriasis-like skin inflammation. The RNA microarray revealed a psoriasis-like gene expression-profile in the Imiquimod treated group, and highlighted several resveratrol dependent changes in relevant genes, such as increased expression of genes associated with retinoic acid stimulation and reduced expression of genes involved in IL-17 dependent pathways (e.g.IL-17A, IL-17F,IL-23p19 ). Quantitative PCR confirmed a resveratrol dependent decrease in mRNA levels of IL-17A and IL-19; both central in developing psoriasis. In conclusion, resveratrol ameliorates psoriasis, and changes in expression of retinoic acid stimulated genes, IL-17 signalling pathways, IL-17A and IL-19 mRNA levels in a beneficial manner suggests it might have a role in the treatment of psoriasis and should be explored further in a human setting.
Project description:Psoriasis is a common inflammatory skin disease in clinic. In order to clarify the mechanism of Longkui Yinxiao soup in treating psoriasis, we used imiquimod-induced psoriasis-like mouse model for sequencing analysis. The results showed that its mechanism of action was mainly related to lipid metabolism.
Project description:Psoriasis is one of the most common dermatological disorders, characterized by increased epidermal hyperplasia and immune cell infiltration. Psychological stress has been reported to contribute to the severity, aggravation, and relapse of psoriasis. We developed a chronic restrain stress (CRS)-imiquimod (IMQ)-induced psoriasis-like mouse model and performed a comprehensive comparative transcriptomic and metabolic analysis with control mice, CRS-treated mice, and IMQ-treated mice to investigate how psychological stress affects psoriasis. We found that CRS-IMQ-induced psoriasis-like mice showed significant exacerbation of psoriasis-like skin inflammation compared with mice treated with IMQ only. Mice of the CRS+IMQ group showed increased expression of keratinocyte proliferation and differentiation genes, differential regulation of cytokines, and promotion of the linoleic acid metabolism. Our study provides new insights into the effects of psychological stress on psoriasis pathogenesis and the mechanisms involved, which provides clues for development of therapeutics or biomarkers.
Project description:In the psoriasis mouse model, depletion of the RNA N6-methylase, Mettl3, from CD4+ T cells inhibits psoriasis-like phenotype and inflammation.
Project description:Patients with psoriasis are at a higher risk of developing nonalcoholic fatty liver disease. We previously identified an oxidized derivative of cholesterol, 7-ketocholesterol (7KC), in diet-induced steatohepatitic mice. Here, we investigated whether 7KC exacerbates psoriasis-like dermatitis by accelerating steatohepatitis in mice. A high fat/high cholesterol/high sucrose/bile salt diet (NASH diet) with or without 0.0125% 7KC was fed to C57BL/6 mice (7KC or control group) for three weeks to induce steatohepatitis. 5% imiquimod cream was then applied to the ears and dorsal skin for four days to induce psoriasis-like dermatitis. Hepatic lipid accumulation and inflammatory cell infiltration were exacerbated in the 7KC group compared with the control group after three weeks. Serum tumor necrosis factor-α (TNF-α) levels were also elevated in the 7KC group (108.5±9.8 vs. 83.1±13.1 pg/ml, p<0.005). Imiquimod cream increased the psoriasis area severity index (PASI) score in mice in the 7KC group (9.14±0.75 vs. 5.17±1.17, p<0.0001). Additionally, Tnfa, Il23a, Il17a, and Il22 mRNA levels in the dorsal lesion were significantly upregulated. Finally, Th17 cell differentiation and the TNF signaling pathway were enhanced in the dorsal lesions and liver of mice in the 7KC group. These data suggest that steatohepatitis and psoriasis are linked by a potent, diet-related factor.