Psoriasis and serum lipid abnormalities

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.

Identifying Serum Metabolomic Markers Associated with Skin Disease Activity in Patients with Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic, systemic, immune-mediated inflammatory disease causing cutaneous and musculoskeletal inflammation that affects 25% of patients with psoriasis. Current methods for evaluating PsA disease activity are not accurate enough for precision medicine. A metabolomics-based approach can elucidate psoriatic disease pathogenesis, providing potential objective biomarkers. With the hypothesis that serum metabolites are associated with skin disease activity, we aimed to identify serum metabolites associated with skin activity in PsA patients. We obtained serum samples from patients with PsA (n = 150) who were classified into mild, moderate and high disease activity groups based on the Psoriasis Area Severity Index. We used solid-phase microextraction (SPME) for sample preparation, followed by data acquisition via an untargeted liquid chromatography-mass spectrometry (LC-MS) approach. Disease activity levels were predicted using identified metabolites and machine learning algorithms. Some metabolites tentatively identified include eicosanoids with anti- or pro-inflammatory properties, like 12-Hydroxyeicosatetraenoic acid, which was previously implicated in joint disease activity in PsA. Other metabolites of interest were associated with dysregulation of fatty acid metabolism and belonged to classes such as bile acids, oxidized phospholipids, and long-chain fatty acids. We have identified potential metabolites associated with skin disease activity in PsA patients.

Crosstalk between cholesterol metabolism and psoriatic inflammation

Psoriasis is a chronic autoinflammatory skin disease associated with multiple comorbidities, with a prevalence ranging from 2 to 3% in the general population. Decades of preclinical and clinical studies have revealed that alterations in cholesterol and lipid metabolism are strongly associated with psoriasis. Cytokines (tumor necrosis factor-α (TNF-α), interleukin (IL)-17), which are important in the pathogenesis of psoriasis, have been shown to affect cholesterol and lipid metabolism. Cholesterol metabolites and metabolic enzymes, on the other hand, influence not only the biofunction of keratinocytes (a primary type of cell in the epidermis) in psoriasis, but also the immune response and inflammation. However, the relationship between cholesterol metabolism and psoriasis has not been thoroughly reviewed. This review mainly focuses on cholesterol metabolism disturbances in psoriasis and their crosstalk with psoriatic inflammation.

The SELP, CD93, IL2RG, and VAV1 Genes Associated with Atherosclerosis May Be Potential Diagnostic Biomarkers for Psoriasis

Purpose

Psoriasis and atherosclerosis are immunometabolic diseases. This study aimed to integrate bioinformatics and updated public resources to find potential biological markers associated with atherosclerosis that can cause psoriasis.

Patients and Methods

Microarray datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were screened, and functional enrichment analysis was performed. We identified psoriasis and atherosclerosis common immune-related genes (PA-IRGs) by overlapping immune-related genes (IRGs) with genes in the module most associated with psoriasis and atherosclerosis obtained by weighted gene co-expression network analysis (WGCNAs). Receiver operating characteristic (ROC) was conducted to evaluate the predictive ability. The skin expression levels of diagnostic biomarkers were further verified by immunohistochemical staining. CIBERSORT, single-sample gene set enrichment analysis (ssGSEA), and Pearson's correlation analysis were applied to evaluate immune and lipid metabolism relationships in psoriatic tissues. In addition, a lincRNA-miRNA-mRNA network was constructed to find the pathogenesis in which diagnostic markers may be involved.

Results

Four PA-IRGs (SELP, CD93, IL2RG, and VAV1) demonstrated the optimal diagnostic value, with an AUC above 0.8. The immune cell infiltration analysis showed that dendritic resting cells, NK cell activation, neutrophils, macrophages M2, macrophages M0, and B-cell memory were highly abundant in psoriasis. Immune response analysis showed that TNF family members, chemokine receptors, interferons, natural killer cells, and TGF-β family members might be involved in psoriasis. Diagnostic biomarkers are strongly associated with various infiltrating immune cells, immune responses, and lipid metabolism. A lincRNA-miRNA-mRNA regulatory network consisting of 31 lincRNAs and 23 miRNAs was constructed. LINC00662 is involved in modulating four diagnostic biomarkers.

Conclusion

This study identified atherosclerosis-related genes SELP, CD93, VAV1, and IL2RG as potential psoriasis diagnostic markers. Provide novel insights into the possible regulatory mechanisms involved in psoriasis.

Inhibition of phospholipases suppresses progression of psoriasis through modulation of inflammation

Abnormal lipid metabolism is regarded as a crucial cause of psoriasis. The specific mechanism of how phospholipase PLA2G4B mediates local immune dysfunction and skin lesions remains unclear. The aim of this study was to explore the mechanisms of anti-psoriasis and immune suppression effect by inhibiting PLA2G4B in psoriasis progression. We successfully transfected si-PLA2G4B in a murine keratinocyte cell-line PAM212 to verify the effect of progression by PLA2G4B. The Imiquimod psoriasis mouse model was then successfully constructed, followed by emulsion wrapped PLA2G4B-siRNA applied to the skin lesions. The phenotype, pathology, immunofluorescence staining of PLA2G4B, IL17, CD3, and CD1b, and bulk transcriptome analysis were performed to decipher the effect and mechanism of si-PLA2G4B. Interfering with PLA2G4B significantly inhibited the proliferation and migration of PAM212. The interference of PLA2G4B in vivo showed a therapeutic effect on psoriasis, comparable to that of betamethasone. The phenotype and pathology revealed reduced keratinocytes in the si-PLA2G4B group compared to the model mice. Immunofluorescence showed that CD1b, CD3+ T cells, and IL17 were suppressed in the skin lesions. RNA-seq and deconvolution revealed that immune cells such as myeloid dendritic cell and T cell CD8+ naive were inactivated. Th17 reduce the release of inflammatory factors such as IL17 and IL36. Pathway analysis revealed the potential therapeutic mechanism involved in the inhibition of sphingolipid or ceramide secretion. This study verified the anti-psoriatic effect of using si-PLA2G4B. The immune response was alleviated after administration. This phospholipase inhibition-based therapy sheds light on the pharmaceutical potential against psoriasis.

Metabonomics Study on Serum Characteristic Metabolites of Psoriasis Vulgaris Patients With Blood-Stasis Syndrome

Psoriasis is a chronic, refractory, systemic inflammatory skin disease. Traditional Chinese medicine (TCM) shows unique advantage in the treatment of psoriasis based on syndrome differentiation. An untargeted high-throughput metabonomics method based on liquid chromatography coupled to mass spectrometry was applied to study the serum metabolic characteristics in different TCM syndrome types in patients with psoriasis vulgaris (PV), and to discover potential serum biomarkers for its pathogenesis on the endogenous metabolite differentiation basis. The serum metabolic profiles of 45 healthy controls and 124 patients with PV (50 in the blood-stasis group, 30 in the blood-heat group, and 44 in the blood-dryness group) were acquired. The raw spectrometric data were processed using multivariate statistical analysis, and 14 biomarkers related to TCM syndrome differentiation and psoriasis types were screened and identified. The blood-stasis syndrome group showed abnormal lipid metabolism, which was characterized by a low level of phosphatidylcholine (PC) and a high level of lysophosphatidylcholine (LPC). We propose that platelet-activating factor can be applied as a potential biomarker in clinical diagnosis and differentiation of PV with blood-stasis syndrome. The difference in the serum metabolites among PV types with different TCM syndromes and healthy control group illustrated the objective material basis in TCM syndrome differentiation and classification of psoriasis.

Cardiovascular Comorbidities in Psoriatic Disease

Psoriatic disease (PsD) is a multisystem inflammatory disorder with a high prevalence of cardiovascular (CV) risk factors contributing to accelerated atherosclerosis and its sequelae. Imaging studies, notably with ultrasound, computed tomography, and positron emission tomography (PET) scanning have confirmed significant atherosclerotic change with plaque formation and vessel stenosis. Atherosclerosis is likely driven by a combination of traditional risk factors which occur more frequently in PsD and by systemic inflammation with associated pro-inflammatory cytokine production. While the mechanisms driving atherosclerosis in PsD are incompletely understood, it is now best practice to try to minimize the impact of CV risk factors by regular assessment, prevention, and treatment and also by ensuring that inflammatory musculoskeletal and cutaneous disease is adequately suppressed. Future studies need to focus on improving our understanding of the mechanisms driving atherosclerosis and, as a consequence, developing more rationale approaches to prevention and treatment.

Serum lipid metabolism in psoriasis and psoriatic arthritis - an update

INTRODUCTION

Psoriasis and psoriatic arthritis (PSA) are chronic, inflammatory, systemic diseases characterized by metabolic abnormalities, including an increased cardiovascular risk and an oxidative imbalance. This study assessed blood parameters of lipid metabolism and markers of oxidative stress in patients with psoriasis and PSA.

MATERIAL AND METHODS

The study included 93 patients with psoriasis (31 patients with PSA and psoriasis, 62 patients with psoriasis vulgaris), and 60 healthy, age-matched controls. Serum concentrations of the glucose and the following lipid metabolism parameters were measured: triglycerides (TG), total cholesterol (TC), low-density lipoproteins (LDL), very low-density lipoproteins (VLDL), high-density lipoproteins (HDL), and apolipoproteins A and B (ApoA, ApoB). Oxidative status was determined as serum concentrations of ox-LDL/MDA Adduct. The Psoriasis Area and Severity Index (PASI) was used to determine disease severity.

RESULTS

Among the three studied groups, controls had the highest HDL concentration (p < 0.001), patients with PSA had the highest ApoB concentration (p < 0.05), ApoA : ApoB ratio (p < 0.05), ox-LDL/MDA adduct concentration (p < 0.001), and TC: HDL and LDL : HDL ratios (accordingly p < 0.05, p < 0.01). In patients with psoriasis or PSA, oxidative status correlated positively with TC and ApoB concentrations.

CONCLUSIONS

In line with previous research, among patients with psoriasis and PSA, we found lipid metabolism abnormalities and an oxidative imbalance, which might be due to chronic inflammation in these conditions. Effective treatment of patients with psoriasis or PSA could reduce the risk of cardiovascular diseases.

Untargeted serum metabonomics study of psoriasis vulgaris based on ultra-performance liquid chromatography coupled to mass spectrometry

Psoriasis is a common, chronic, systemic inflammatory skin disease, the etiology and pathogenesis is unclear. An untargeted high-throughput metabonomics method based on liquid chromatography coupled to mass spectrometry was applied to study the serum metabolic changes in psoriasis vulgaris patients, and to discover serum potential biomarkers for identification, diagnosis and exploring pathogenesis of psoriasis. The serum metabolic profiles from 150 subjects (75 psoriasis patients and 75 healthy controls) were acquired, the raw spectrometric data were processed by multivariate statistical analysis, and 44 potential biomarkers were screened out and identified. The potential biomarkers were mainly involved in glycerophospholipid metabolism, sphingolipid metabolism, arachidonic acid metabolism, bile acid biosynthesis, indicated the pathogenesis of psoriasis may be related to the disturbed metabolic pathways.

Combined Transcriptomic Analysis Revealed AKR1B10 Played an Important Role in Psoriasis through the Dysregulated Lipid Pathway and Overproliferation of Keratinocyte

RNA-seq has enabled in-depth analysis of the pathogenesis of psoriasis on the transcriptomic level, and many biomarkers have been discovered to be related to the immune response, lipid metabolism, and keratinocyte proliferation. However, few studies have combined analysis from various datasets. In this study, we integrated different psoriasis RNA-seq datasets to reveal the pathogenesis of psoriasis through the analysis of differentially expressed genes (DEGs), pathway analysis, and functional annotation. The revealed biomarkers were further validated through proliferation phenotypes. The results showed that DEGs were functionally related to lipid metabolism and keratinocyte differentiation dysregulation. The results also showed new biomarkers, such as AKR1B10 and PLA2G gene families, as well as pathways that include the PPAR signaling pathway, cytokine-cytokine receptor interaction, alpha-linoleic acid metabolism, and glycosphingolipid biosynthesis. Using siRNA knockdown assays, we further validated the role that the AKR1B10 gene plays in proliferation. Our study demonstrated not only the dysfunction of the AKR1B10 gene in lipid metabolizing but also its important role in the overproliferation and migration of keratinocyte, which provided evidence for further therapeutic uses for psoriasis.

Imiquimod induced ApoE-deficient mice might be a composite animal model for the study of psoriasis and dyslipideamia comorbidity

BACKGROUND

Psoriasis patients are at increased risk of developing lipid metabolism disturbances. Both psoriasis and dyslipideamia not only closely interact in disease development, but occur as mutual side effects in some medicine treatment. The interactive mechanism of the two diseases is complicated and still unclear.

OBJECTIVE

Here, we proposed applying imiquimod on the dorsal skin of ApoE^-/- mice to establish a composite animal model which formed psoriasiform skin lesions under hyperlipidemic condition.

METHOD

By comparison with corresponding wild-type(C57BL/6) mice, the composite mice model was evaluated by skin pathological features, lipid levels, immune inflammatory factors in order to clarify the diseases interplay mechanism. In addition, IL-17 mAb treatment was applied to observe the effect of IL-17 antibody on the composite animal model.

RESULTS

The results verified that imiquimod-induced ApoE^-/- mice model presented keratinocyte hyperplasia, parakeratosis, inflammatory cells infiltration and elevated serum lipid levels, and also reflected the complex interaction between inflammation and lipid metabolism. IL-17 mAb could inhibit psoriasis skin lesions with lipid accumulation via STAT3 pathway, but no influence on elevated serum cholesterol.

CONCLUSIONS

Imiquimod-induced ApoE^-/- mice model presented the pathological features of psoriasis and dyslipideamia, which could be an ideal composite animal model for the study of pathogenesis and pharmacotherapeutics of psoriasis and dyslipideamia comorbidity.

Apolipoprotein E gene polymorphism and serum lipid profile in Saudi patients with psoriasis

Background/Aim. Apolipoprotein E (APOE) gene variants have been reported to influence psoriasis risk. However, data is limited to a few ethnicities and no similar study has been performed in middle eastern populations. We investigated this association in Saudi psoriasis patients. Methods. Saudi subjects (294) were genotyped for APOE gene using APOE StripAssay kit. Results. The frequencies of alleles ε2, ε4, and genotypes ε3/ε4 and ε3/ε2 were significantly higher in psoriasis patients compared with those in controls. The frequency of ε3 allele and ε3/ε3 genotype was significantly lower in patients. Other genotypes, ε2/ε4, ε2/ε2, and ε4/ε4, were absent in both groups. The serum cholesterol, triglycerides, and LDL levels were significantly higher in psoriasis patients contrary to HDL level. Patients with APOE ε4 had significantly higher levels of total cholesterol and LDL cholesterol, whereas those with the ε2 had higher HDL cholesterol, and triglycerides. Conclusion. APOE alleles ε2, ε4, and genotypes ε2/ε3 and ε4/ε3 are associated with psoriasis and can be a risk factor while allele ε3 and genotype ε3/ε3 may be protective for psoriasis in Saudis. Results of lipid profile support that psoriasis is one of the independent risk factors for hyperlipidemia and emphasize the need of screening cardiovascular diseases in psoriatic patients.

Lipid disturbances in psoriasis: an update

Psoriasis is a common disease with the population prevalence ranging from 2% to 3%. Its prevalence in the population is affected by genetic, environmental, viral, infectious, immunological, biochemical, endocrinological, and psychological factors, as well as alcohol and drug abuse. In the recent years, psoriasis has been recognised as a systemic disease associated with numerous multiorgan abnormalities and complications. Dyslipidemia is one of comorbidities in psoriatic patients. Lipid metabolism studies in psoriasis have been started at the beginning of the 20th century and are concentrated on skin surface lipids, stratum corneum lipids and epidermal phospholipids, serum lipids, dermal low-density lipoproteins in the psoriatic skin, lipid metabolism, oxidative stress and correlations between inflammatory parameters, lipid parameters and clinical symptoms of the disease. On the basis of the literature data, psoriasis can be described as an immunometabolic disease.