Lipid Alterations and Metabolism Disturbances in Selected Inflammatory Skin Diseases

Novel immune cross-talk between inflammatory bowel disease and IgA nephropathy

The mechanisms underlying the complex correlation between immunoglobulin A nephropathy (IgAN) and inflammatory bowel disease (IBD) remain unclear. This study aimed to identify the optimal cross-talk genes, potential pathways, and mutual immune-infiltrating microenvironments between IBD and IgAN to elucidate the linkage between patients with IBD and IgAN. The IgAN and IBD datasets were obtained from the Gene Expression Omnibus (GEO). Three algorithms, CIBERSORTx, ssGSEA, and xCell, were used to evaluate the similarities in the infiltrating microenvironment between the two diseases. Weighted gene co-expression network analysis (WGCNA) was implemented in the IBD dataset to identify the major immune infiltration modules, and the Boruta algorithm, RFE algorithm, and LASSO regression were applied to filter the cross-talk genes. Next, multiple machine learning models were applied to confirm the optimal cross-talk genes. Finally, the relevant findings were validated using histology and immunohistochemistry analysis of IBD mice. Immune infiltration analysis showed no significant differences between IBD and IgAN samples in most immune cells. The three algorithms identified 10 diagnostic genes, MAPK3, NFKB1, FDX1, EPHX2, SYNPO, KDF1, METTL7A, RIDA, HSDL2, and RIPK2; FDX1 and NFKB1 were enhanced in the kidney of IBD mice. Kyoto Encyclopedia of Genes and Genomes analysis showed 15 mutual pathways between the two diseases, with lipid metabolism playing a vital role in the cross-talk. Our findings offer insights into the shared immune mechanisms of IgAN and IBD. These common pathways, diagnostic cross-talk genes, and cell-mediated abnormal immunity may inform further experimental studies.

Atopic Dermatitis and Psoriasis: Similarities and Differences in Metabolism and Microbiome

Atopic dermatitis and psoriasis are common chronic inflammatory diseases of high incidence that share some clinical features, including symptoms of pruritus and pain, scaly lesions, and histologically, acanthosis and hyperkeratosis. Meanwhile, they are both commonly comorbid with metabolic disorders such as obesity and diabetes, indicating that both diseases may exist with significant metabolic disturbances. Metabolomics reveals that both atopic dermatitis and psoriasis have abnormalities in a variety of metabolites, including lipids, amino acids, and glucose. Meanwhile, recent studies have highlighted the importance of the microbiome and its metabolites in the pathogenesis of atopic dermatitis and psoriasis. Metabolic alterations and microbiome dysbiosis can also affect the immune, inflammatory, and epidermal barrier, thereby influencing the development of atopic dermatitis and psoriasis. Focusing on the metabolic and microbiome levels, this review is devoted to elaborating the similarities and differences between atopic dermatitis and psoriasis, thus providing insights into the intricate relationship between both conditions.

Adult and infantile seborrheic dermatitis: update on current state of evidence and potential research frontiers

Seborrheic dermatitis (SD) is a highly prevalent dermatological condition globally. The condition demonstrates bimodal presentation with what is commonly thought to be two subtypes: adult/adolescent seborrheic dermatitis (ASD) and infantile seborrheic dermatitis (ISD). Despite the common prevalence of ASD and ISD, there remains uncertainty around the underlying pathogenetic mechanisms, risk factors, and appropriate classification of the disease(s). This narrative review summarizes the current understanding of the epidemiology, presentation, and pathogenetic factors like epidermal barrier dysfunction, lipid abnormalities, and cutaneous microbiome for ASD and ISD. Elements such as immune responsiveness, neuroendocrine factors, and genetics in these disease states are also investigated. Throughout our review, we highlight shared features and discrepancies between ASD and ISD that are present in the literature and discuss potential avenues for future research that explore these disease states. We aim to contribute to the medical discourse on ASD and ISD and increase awareness of the need for additional research around these conditions, ultimately informing better targeting of therapeutics moving forward.

Repurposing lipid-lowering drugs as potential treatment for acne vulgaris: a Mendelian randomization study

Background

Acne vulgaris, a chronic inflammatory skin condition predominantly seen in teenagers, impacts more than 640 million people worldwide. The potential use of lipid-lowering medications as a treatment for acne vulgaris remains underexplored. This study seeks to investigate the impact of lipid-lowering therapies on the risk of developing acne vulgaris using two-sample Mendelian randomization (MR) analysis.

Method

The two-sample MR method was employed for analysis, and information on lipid-lowering drugs was obtained from the DrugBank and ChEMBL databases. The summary data for blood low-density lipoprotein (LDL) and triglycerides were sourced from the Global Lipids Genetics Consortium, while genome-wide association studies (GWAS) summary data for acne vulgaris were obtained from the FinnGen database. Heterogeneity was examined using the Q-test, horizontal pleiotropy was assessed using MR-Presso, and the robustness of analysis results was evaluated using leave-one-out analysis.

Results

The MR analysis provided robust evidence for an association between lowering LDL cholesterol through two drug targets and acne vulgaris, with PCSK9 showing an odds ratio (OR) of 1.782 (95%CI: 1.129-2.812, p = 0.013) and LDL receptor (LDLR) with an OR of 1.581 (95%CI: 1.071-2.334, p = 0.021). Similarly, targeting the lowering of triglycerides through lipoprotein lipase (LPL) was significantly associated with an increased risk of acne vulgaris, indicated by an OR of 1.607 (95%CI: 1.124-2.299, p = 0.009).

Conclusion

The current MR study presented suggestive evidence of a positive association between drugs targeting three genes (PCSK9, LDLR, and LPL) to lower lipids and a reduced risk of acne vulgaris.

The causal relationship between blood metabolites and rosacea: A Mendelian randomization

BACKGROUND

An increasing amount of research demonstrates that metabolic disorders are related to rosacea. However, the correlations and causal relationships among them remain unknown.

METHODS

We conducted not only forward 2-sample MR (Mendelian randomization) analyses but also reverse MR analyses which showed positive results in the forward MR analysis. In the forward MR analyses, inverse-variance weighted (IVW) and MR-Egger were performed as MR analyses. Cochran's Q test and the MR-Egger Intercept were used for sensitivity analyses. Concerning reverse MR analyses, IVW, MR-Egger, weighted median, simple mode, and weighted mode were applied. Cochran's Q test, MR-Egger Intercept, and MR pleiotropy residual sum and outlier (MR-PRESSO) outlier test were applied as sensitivity analyses.

RESULTS

A total of 24 metabolites and 1 metabolite ratio were shown to have a causal effect on rosacea. N-lactoyl phenylalanine (N-Lac-Phe) was estimated as statistically significant by Bonferroni correction. Interestingly, we found three metabolites that were negatively associated with rosacea, especially caffeine, which are in line with the results of a large cohort study of females. For reverse MR analysis, we revealed that rosacea could potentially decrease the generation of two metabolites: octadecenedioate (C18:1-DC) and methyl vanillate sulfate.

CONCLUSION

This study identified blood metabolites that may be associated with the development of rosacea. However, the exact mechanism by which these positive metabolites influence rosacea remains uncertain due to the paucity of experimental investigations. The combination of genetics and metabolomics offers novel viewpoints on the research of underlying mechanisms of rosacea and has significant value in screening and prevention of rosacea.

Elucidating the Role of Lipid-Metabolism-Related Signal Transduction and Inhibitors in Skin Cancer

Lipids, as multifunctional molecules, play a crucial role in a variety of cellular processes. These include regulating membrane glycoprotein functions, controlling membrane trafficking, influencing apoptotic pathways, and affecting drug transport. In addition, lipid metabolites can alter the surrounding microenvironment in ways that might encourage tumor progression. The reprogramming of lipid metabolism is pivotal in promoting tumorigenesis and cancer progression, with tumors often displaying significant changes in lipid profiles. This review concentrates on the essential factors that drive lipid metabolic reprogramming, which contributes to the advancement and drug resistance in melanoma. Moreover, we discuss recent advances and current therapeutic strategies that employ small-molecule inhibitors to target lipid metabolism in skin cancers, particularly those associated with inflammation and melanoma.

Comparative study of melasma in patients before and after treatment based on lipomics

BACKGROUND

Skin barrier alterations play a crucial function in melasma development. Past researches have demonstrated variations in lipid content between the epidermis of melasma lesions and normal tissues, along with the varied expression of lipid-related genes in melasma. This study aimed to analyze the lipidome profiles of skin surface lipids (SSL) in patients with melasma before and after treatment to understand associated abnormalities.

METHODS

Melasma was treated with tranexamic acid orally and hydroquinone cream topically. Disease was assessed using the Melasma Area and Severity Index (MASI), and the impact to life was evaluated with Melasma Quality of Life (MELASQoL) score. Epidermal melanin particles were observed using reflection confocal microscopy (RCM), whereas epidermal pigment and blood vessel morphology were observed using dermoscopy, and SSL samples were collected. Specific information regarding alterations in lipid composition was obtained through multivariate analysis of the liquid chromatography-mass spectrometry data.

RESULTS

After treatment, patients with melasma exhibited decreased MASI and MELASQoL scores (P < 0.001); RCM revealed reduced melanin content in the lesions, and dermoscopy revealed fewer blood vessels. Fifteen lipid subclasses and 382 lipid molecules were identified using lipidomic assays. The expression levels of total lipids, phosphatidylcholine, and phosphatidylethanolamine in the melasma lesions decreased after treatment (P < 0.05).

CONCLUSION

This study revealed alterations in the SSL composition after effective melasma treatment, suggesting a compensatory role for lipids in melasma barrier function. The mechanism involving SSL and the lipid barrier, which influences melasma's occurrence, needs further elucidation.

Development and trends in metabolomics studies in psoriasis: A bibliometric analysis of related research from 2011 to 2024

Background

Psoriasis is a chronic, inflammatory skin disease with autoimmune characteristics. Recent research has made significant progress in the field of psoriasis metabolomics. However, there is a lack of bibliometric analysis on metabolomics of psoriasis. The objective of this study is to utilize bibliometrics to present a comprehensive understanding of the knowledge structure and research hotspots in psoriasis within the field of metabolomics.

Methods

We conducted a bibliometric analysis by searching the Web of Science Core Collection database for publications on metabolomics in psoriasis from 2011 to 2024. To perform this analysis, we utilized tools such as VOSviewers, CiteSpace, and the R package "bibliometrix".

Results

A total of 307 articles from 47 countries, with the United States and China leading the way, were included in the analysis. The publications focusing on metabolomics in psoriasis have shown a steady year-on-year growth. The Medical University of Bialystok is the main research institution. The International Journal of Molecular Sciences emerges as the prominent journal in the field, while the Journal of Investigative Dermatology stands out as the highly co-cited publication. A total of 2029 authors contributed to these publications, with Skrzydlewska Elzbieta, Baran Anna, Flisiak Iwona, Murakami Makoto being the most prolific contributors. Notably, Armstrong April W. received the highest co-citation. Investigating the mechanisms of metabolomics in the onset and progression of psoriasis, as well as exploring therapeutic strategies, represents the primary focus of this research area. Emerging research hotspots encompass inflammation, lipid metabolism, biomarker, metabolic syndrome, obesity, and arthritis.

Conclusion

The results of this study indicate that metabolism-related research is thriving in psoriasis, with a focus on the investigation of metabolic targets and interventions within the metabolic processes. Metabolism is expected to be a hot topic in future psoriasis research.

Cholesterol and low-density lipoprotein as a cause of psoriasis: Results from bidirectional Mendelian randomization

BACKGROUND

Psoriasis is an inflammatory disease that affects many people. However, the causal effect of lipid metabolism on psoriasis has not yet been verified. This study aimed to identify the genetic relationship between serum lipid levels and psoriasis.

METHODS

Bidirectional two-sample Mendelian randomization (MR) was used to analyse the causal relationship between cholesterol and psoriasis. The outcome of the forward causality test was psoriasis. In the analysis of reverse causality, psoriasis was exposed, and 79 single-nucleotide polymorphisms were detected in the genome-wide association study (GWASs) database from the IEU GWASs Project. MR-Egger regression, inverse variance-weighted, weighted median, weighted mode and simple mode were used for the MR analyses.

RESULTS

The level of triglyceride, lipase member N, chylomicrons, extremely large very low-density lipoprotein (VLDL) particles, high-density lipoprotein (HDL) cholesterol levels, cholesterol esters in large HDL, cholesterol esters in medium HDL and cholesterol esters in medium VLDL have not affected the development of psoriasis. However, total cholesterol, total free cholesterol, low-density lipoprotein (LDL) cholesterol levels, cholesterol esters in large VLDL and cholesterol esters in medium LDL were unidirectional causal effects on psoriasis.

CONCLUSION

Bidirectional two-sample MR analysis indicated that high levels of total cholesterol, total free cholesterol, LDL cholesterol, cholesterol esters in large VLDL and cholesterol esters in medium LDL are genetic risk factors for psoriasis.

A Review of Dupilumab in the Treatment of Atopic Dermatitis in Infants and Children

Atopic dermatitis (AD), a common pruritic and chronic inflammatory skin disease, has a major impact on a patient's quality of life. It is characterized by dry, itchy, and eczema-like rashes. AD is more prevalent in young children and has been linked to a variety of other allergy disorders. Traditional drug therapy has certain limitations for treating young children with AD. However, biologics have good clinical application prospects in the medical treatment of young patients. Dupilumab, a fully human monoclonal antibody, specifically binds to the IL-4 Rα subunit, inhibiting IL-4 and IL-13 signaling and blocking the occurrence of type 2 inflammatory response. It has a good effect on treating infants and children with moderate-to-severe AD. This review explores the safety and efficacy of dupilumab in the treatment of AD in infants and children and the impact of early intervention on AD progression, with the aim of informing clinical practice in the use of dupilumab for the treatment of young patients with AD.

Daturataturin A Ameliorates Psoriasis by Regulating PPAR Pathway

Psoriasis is a kind of severe immune-mediated systemic skin disorder, becoming a worldwide public health concern. Daturataturin A (DTA), a withanolide compound, exerts excellent anti-inflammatory and anti-proliferative properties. The objective of this study is to elucidate the effect of DTA on psoriasis and its potential mechanism. We established psoriasis-like keratinocytes model by stimulating HaCaT cells with M5 cocktail cytokines including Interleukin (IL)-17A, IL-22, oncostatin M, IL-1α, and tumor necrosis factor-α (TNF-α), followed by intervention with DTA. The potential effects and mechanisms of DTA on psoriasis were evaluated in vitro. DTA was found to be able to inhibit hyperproliferation, promote apoptosis, decrease the release of pro-inflammatory cytokines, downregulate keratin expression, and improve lipid metabolism via regulating the peroxisome proliferator-activated receptor (PPAR) signaling pathway by M5 cocktail cytokines stimulation in HaCaT cells. DTA ameliorated lipid metabolism of psoriasis and exerted the potential anti-psoriasis effects by regulating PPAR pathway in vitro, suggesting that DTA may act as a new therapeutic agent for psoriasis.