Endoplasmic Reticulum Dysfunction: An Emerging Mechanism of Vitiligo Pathogenesis.

The endoplasmic reticulum (ER) is the main site of protein synthesis, transport, and modification. Its abnormal status has now emerged as an established cause of many pathological processes, such as tumors and autoimmune diseases. Recent studies also demonstrated that the defective functions of ER may lead to pigmentary diseases. Vitiligo is a depigmenting ailment skin disorder whose pathogenesis is now found to be associated with ER. However, the detailed mechanism is still unclear. In this review, we try to link the association between ER with its inter- and intra-organellar interactions in vitiligo pathogenesis and focus on the function, mechanism, and clinical potential of ER with vitiligo. Expand ER is found in melanocytes of vitiligo and ER stress (ERS) might be a bridge between oxidative stress and innate and adaptive immunity. Meanwhile, the tight association between ER and mitochondria or melanosomes in organelles levels, as well as genes and cytokines, is the new paradigm in the pathogenesis of vitiligo. This undoubtedly adds a new aspect to the understanding of vitiligo, facilitating the design of targeted therapies for vitiligo.

Discovering Novel Biomarkers Associated with the Pathogenesis of Psoriasis: Evidence from Bioinformatic Analysis.

Objective: This study aimed to investigate key biomarkers and their molecular pathogenesis in psoriasis. Methods: Differentially expressed genes (DEGs) of datasets (GSE13355, GSE30999, and GSE106992) obtained from Gene Expression Omnibus (GEO) were identified using Venn diagram. Function and pathway enrichment analyses were performed. Protein-protein interaction (PPI) network and the hub genes were constructed. The correlation between normal tissue and infiltrating immune cells was analyzed by CIBERSORT. ROC analysis was performed to distinguish between skin lesion samples and skin non-lesion samples. Analyze the highest expression of single gene in the whole body within the Human Protein Atlas (HPA) database. Effect of CXCL8 expression level on proliferation, invasion, migration and apoptosis of HaCat cells was detected by qPCR. Results: A total of 239 pairs of normal and lesional skin samples were downloaded. PPI network revealed a tight interaction among 197 DEGs. The GO enrichment analysis showed that these genes were markedly enriched in the "defense response to virus", "type I interferon signaling pathway", and "cell response to type I interferon" categories. The KEGG pathway analysis showed that the DEGs were mainly in the NOD-like receptor axis, interaction between cytokine and cytokine receptor and the IL-17 axis. PPI analysis showed that CXCL8 was the novel hub gene of psoriasis and correlated to 22 types of infiltrating immune cells. 6 miRNAs were predicted to be related to CXCL8. CXCL8 was most widely distributed in lymphoid tissues and plays a role in psoriatic inflammatory lesions by promoting cell proliferation, migration, and anti-apoptosis. Conclusion: CXCL8 plays a key role in psoriasis development. This study provided new insights into the exploration of molecular mechanisms and therapeutic targets of psoriasis.

Integrated bioinformatic analysis of key biomarkers and signalling pathways in psoriasis.

BACKGROUND AND AIMS: Psoriasis is a relatively common autoimmune inflammatory skin disease with a chronic etiology. Since psoriasis is still incurable, it is necessary to identify the molecular mechanisms of psoriasis. The present study was designed to detect novel biomarkers and pathways associated with psoriasis incidence, and provide new insights into treatment of psoriasis. METHODS AND RESULTS: Differentially expressed genes (DEGs) associated with psoriasis in the Gene Expression Omnibus (GEO) database were identified, and their functional roles and interactions were then annotated and evaluated through GO, KEGG, and gene set variation (GSVA) analyses. In total 197 psoriasis-related DEGs were identified and found to primarily be associated with the NOD-like receptor, IL-17, and cytokine-cytokine receptor interaction signalling pathways. GSVA revealed significant differences between normal and lesional groups (P < 0.05), while PPI network analyses identified CXCL10 as the hub gene with the highest degree value, whereas IRF7, IFIT3, OAS1, GBP1, and ISG15 were promising candidate genes for the therapeutic treatment of psoriasis. CONCLUSION: The findings of the present integrated bioinformatics may enhance our understanding of the molecular events occurring in psoriasis, and these candidate genes and pathways together may prove to be therapeutic targets for psoriasis.

Herb Sanqi-Derived Compound K Alleviates Oxidative Stress in Cultured Human Melanocytes and Improves Oxidative-Stress-Related Leukoderma in Guinea Pigs.

Sanqi, a traditional Chinese herb, is widely used for cardiovascular diseases, and its neuroprotective effects against oxidative stress were recently discovered. The purpose of this study was to investigate whether Sanqi-derived compound K (Sanqi-CK), an active metabolite of Sanqi, could protect melanocytes from oxidative stress. Cultured human primary skin epidermal melanocytes (HEMn-MPs) were treated with hydrogen peroxide (H2O2) in the presence or absence of Sanqi-CK. Sanqi-CK exhibited protective effects against H2O2-induced cell death by reducing oxidative stress. In addition, treatment with Sanqi-CK reversed the decreased glutathione reductase activity and decreased ratio of reduced glutathione (GSH)/oxidized glutathione (GSSG) seen in H2O2-treated melanocytes. Furthermore, topical application of Sanqi-CK alleviated leukoderma in guinea pigs, a disorder characterized by melanocyte cell death resulting from rhododendrol-induced oxidative stress. Taken together, these data suggest that Sanqi-CK protects melanocytes against oxidative stress, and its protective effects are associated with modulating the redox balance between GSH and GSSG and activating glutathione reductase. Thus, Sanqi-CK may be a good candidate for preventing melanocyte loss in oxidative-stress-associated pigmentary disorders.

Successful secukinumab treatment of erythrodermic psoriasis and psoriatic arthritis concomitant with severe noninfectious uveitis: a case report.

Uveitis is considered a relatively rare but serious ocular complication of psoriasis. We report the first successful treatment of severe noninfectious uveitis with secukinumab in a 70-year-old woman with erythrodermic psoriasis and psoriatic arthritis. Anti-tumor necrosis factor (TNF) agents were administered for 5 years for the treatment of erythrodermic psoriasis and psoriatic arthritis. Although the symptoms improved, she later developed noninfectious uveitis, resulting in a sharp decline in vision. After switching to secukinumab, her vision slightly improved, her skin lesions subsided, and her joint symptoms were relieved. Given the rarity of psoriasis combined with uveitis, it is unclear whether uveitis is related to anti-TNF therapy. In addition, the selection of effective biological agents for the treatment of uveitis remains a challenge and requires extensive clinical experience.