Metabolomic profiling between vitiligo patients and healthy subjects in plateau exhibited significant differences with those in plain

Serum metabolomic characteristics of COVID-19 patients co-infection with echovirus

Currently, the Omicron variant of the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to circulate globally. In our multiplex respiratory pathogen detection, we identified numerous instances of co-infection with Echovirus (ECHO) among Coronavirus Disease 2019 (COVID-19) patients, which exacerbated the clinical symptoms of these patients. Such co-infections are likely to impact the subsequent medical treatment. To date, there are no reports on the pathogenic mechanisms related to COVID-19 co-infected with ECHO. Therefore, this study employed the TM Widely-Targeted metabolomics approach to analyze the serum metabolomes of COVID-19 patients with single SARS-CoV-2 infection (COVID-19), COVID-19 patients co-infected with ECHO (COVID-19  +  ECHO), and healthy individuals (Control) recruited from routine physical examinations during the same period. Concurrent clinical laboratory tests were performed on the patients to reveal the differences in metabolomic characteristics between the COVID-19 patients and the COVID-19  +  ECHO patients, as well as to explore potential metabolic pathways that may exacerbate disease progression. Our findings indicate that both clinical examination indicators and the pathways enriched by differential metabolites confirm that patients with dual infection exhibit higher inflammatory and immune responses compared to those with single COVID-19 infections. This difference is likely reflected through abnormalities in the glycerophospholipid metabolic pathway, with the metabolite Sn-Glycero-3-Phosphocholine playing a crucial role in this process. Finally, we established a diagnostic model based on logistic regression using five differential metabolites, which accurately differentiates between the dual infection population and the single COVID-19 infection population (AUC = 0.828).

Glucose transporter-1 (GLUT-1) upregulation in vitiligo: A possible link to skin depigmentation

BACKGROUND

Vitiligo is a prevalent autoimmune skin disorder characterized by progressive depigmented patches of the skin and/or mucosa. Lately, extensive research has been investigating molecular pathogenesis underlying vitiligo, epidermal-immune cell crosstalk, structural aberrations in cellular skin components and immune cell metabolism derangements. Glucose transporter-1 (GLUT-1) has recently proved to be increased in proinflammatory conditions and autoimmune diseases. GLUT-1 expression is upregulated in rheumatoid arthritis, systemic lupus erythematosus, psoriasis and chronic spongiotic dermatitis.

OBJECTIVE

To investigate GLUT-1 expression in vitiligo.

SUBJECTS AND METHODS

The study included 30 vitiligo patients "vitiligo vulgaris" and 30 healthy individuals. Biopsies of the patients' lesional vitiligo skin and the control group's normal skin were obtained. They were all tested for GLUT-1 mRNA expression using real-time polymerase chain reaction (RT-PCR) and GLUT-1 antibody expression using immunohistochemistry (IHC). Hematoxylin and eosin (H&E) staining for the specimens was additionally done for histopathological assessment.

RESULTS

GLUT-1 expression was upregulated in lesional skin of vitiligo patients compared to normal control skin (P-value < 0.001). Also, lesional specimens from stable disease showed more GLUT-1 expression than active disease but without a significant difference (P-value = 0.283). There was no significant correlation between the proposed vitiligo histological scoring system and vitiligo signs of the disease activity score.

CONCLUSION

GLUT-1 could play a crucial role in vitiligo disease onset, persistence and progression, through keratinocyte-melanocyte-fibroblast-immune cell crosstalk, being the initially deranged metabolic pathway for all these cells giving an insight into vitiligo metabolomics.

The Role of Bile Acid in Immune-Mediated Skin Diseases

Immune-mediated skin disorders arise from dysfunctional immune responses, instigating inflammatory dermatoses and a reduced quality of life. The complex pathogenesis likely involves genetic risks, environmental triggers and aberrant immune activation. An emerging body of evidence suggests that bile acid disturbances may critically promote immune pathology in certain skin conditions. Bile acids synthesised from cholesterol regulate nutrient metabolism and immune cell function via nuclear receptors and G protein-coupled receptors (GPCRs). Altered bile acid profiles and receptor expression have been identified in psoriasis, atopic dermatitis (AD) and autoimmune blistering diseases. Disruptions in bile acid signalling affect the inflammatory and metabolic pathways linked to these disorders. Targeting components of the bile acid axis represents a promising therapeutic strategy. This review elucidates the intricate links between bile acid homeostasis and immune dysfunction in inflammatory skin diseases, synthesising evidence that targeting bile acid pathways may unlock innovative therapeutic avenues. This study compiles clinical and experimental data revealing disrupted bile acid signalling and composition in various immune-mediated dermatoses, highlighting the emerging significance of bile acids in cutaneous immune regulation.

An Overview of the Biological Complexity of Vitiligo

Vitiligo is a skin disease that affects all ethnicities and genders and is characterized by the loss of pigment essentially due to the selective loss of melanocytes. Although it is generally considered a systemic disease associated with polymorphisms in genes involved in the immune response, vitiligo is also considered an oxidative imbalance-associated disease. It represents a multifactorial pathology in which some genetic predisposition and epigenetic factors coupled with some critical biochemical and molecular pathways could play a pivotal role. The aim of this work was thus to review some of the fine cellular mechanisms involved in the etiopathogenesis of vitiligo, mainly focusing on the nonimmunological ones, extensively highlighted elsewhere. We took into consideration, in addition to oxidative stress, both the cause and the hallmark of the pathology, some less investigated aspects such as the role of epigenetic factors, e.g., microRNAs, of receptors of catecholamines, and the more recently recognized role of the mitochondria. Sex differences associated with vitiligo have also been investigated starting from sex hormones and the receptors through which they exert their influence. From literature analysis, a picture seems to emerge in which vitiligo can be considered not just a melanocyte-affecting disease but a systemic pathology that compromises the homeostasis of a complex tissue such as the skin, in which different cell types reside playing multifaceted physiological roles for the entire organism. The exact sequence of cellular and subcellular events associated with vitiligo is still a matter of debate. However, the knowledge of the individual biological factors implicated in vitiligo could help physicians to highlight useful innovative markers of progression and provide, in the long run, new targets for more tailored treatments based on individual manifestations of the disease.

Exploring the roles and potential therapeutic strategies of inflammation and metabolism in the pathogenesis of vitiligo: a mendelian randomization and bioinformatics-based investigation

Introduction

Vitiligo, a common autoimmune acquired pigmentary skin disorder, poses challenges due to its unclear pathogenesis. Evidence suggests inflammation and metabolism's pivotal roles in its onset and progression. This study aims to elucidate the causal relationships between vitiligo and inflammatory proteins, immune cells, and metabolites, exploring bidirectional associations and potential drug targets.

Methods

Mendelian Randomization (MR) analysis encompassed 4,907 plasma proteins, 91 inflammatory proteins, 731 immune cell features, and 1400 metabolites. Bioinformatics analysis included Protein-Protein Interaction (PPI) network construction, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Subnetwork discovery and hub protein identification utilized the Molecular Complex Detection (MCODE) plugin. Colocalization analysis and drug target exploration, including molecular docking validation, were performed.

Results

MR analysis identified 49 proteins, 39 immune cell features, and 59 metabolites causally related to vitiligo. Bioinformatics analysis revealed significant involvement in PPI, GO enrichment, and KEGG pathways. Subnetwork analysis identified six central proteins, with Interferon Regulatory Factor 3 (IRF3) exhibiting strong colocalization evidence. Molecular docking validated Piceatannol's binding to IRF3, indicating a stable interaction.

Conclusion

This study comprehensively elucidates inflammation, immune response, and metabolism's intricate involvement in vitiligo pathogenesis. Identified proteins and pathways offer potential therapeutic targets, with IRF3 emerging as a promising candidate. These findings deepen our understanding of vitiligo's etiology, informing future research and drug development endeavors.