Dysregulated tryptophan metabolism and AhR pathway contributed to CXCL10 upregulation in stable non-segmental vitiligo.

BACKGROUND: Tryptophan metabolism dysregulation has been observed in vitiligo. However, drawing a mechanistic linkage between this metabolic disturbance and vitiligo pathogenesis remains challenging. OBJECTIVE: Aim to reveal the characterization of tryptophan metabolism in vitiligo and investigate the role of tryptophan metabolites in vitiligo pathophysiology. METHODS: LC-MS/MS, dual-luciferase reporter assay, ELISA, qRT-PCR, small interfering RNA, western blotting, and immunohistochemistry were employed. RESULTS: Kynurenine pathway activation and KYAT enzyme-associated deviation to kynurenic acid (KYNA) in the plasma of stable non-segmental vitiligo were determined. Using a public microarray dataset, we next validated the activation of kynurenine pathway was related with inflammatory-related genes expression in skin of vitiligo patients. Furthermore, we found that KYNA induced CXCL10 upregulation in keratinocytes via AhR activation. Moreover, the total activity of AhR agonist was increased while the AhR concentration per se was decreased in the plasma of vitiligo patients. Finally, higher KYAT, CXCL10, CYP1A1 and lower AhR expression in vitiligo lesional skin were observed by immunohistochemistry staining. CONCLUSION: This study depicts the metabolic and genetic characterizations of tryptophan metabolism in vitiligo and proposes that KYNA, a tryptophan-derived AhR ligand, can enhance CXCL10 expression in keratinocytes.

Comparative Analysis of P-selectin Levels in Psoriasis, Vitiligo, and Nonskin Disease in a Tertiary Care Hospital: A Case-Control Study.

INTRODUCTION: The role and function of P-selectin levels in various inflammatory and immune-mediated diseases have been established. Whether they have an association with inflammatory skin diseases such as vitiligo and psoriasis needs to be established. OBJECTIVE: The objective of this study was to assess P-selectin levels in psoriasis and vitiligo and to compare them with matched controls without skin disease. MATERIALS AND METHODS: The study included a total of 90 subjects with age- and sex-matched - 30 each in psoriasis, vitiligo and 30 controls without skin disease. Psoriasis and vitiligo severity was assessed using the Psoriasis Area and Severity Index and the Vitiligo Area Scoring Index scores. P-selectin levels were assessed and compared among the groups. P-selectin levels were also compared with the severity of psoriasis and vitiligo. Chi-square and analysis of variance tests were used to compare the data. RESULTS: The mean age of subjects was 36.28 ± 11.80 years. Majority of the subjects were males (65.6%). The three groups were matched for age, sex, and other demographics. The mean P-selectin levels were 610.43 ± 134.19, 292.52 ± 60.99, and 158.97 ± 34.76 ng/ml, respectively, in the psoriasis, vitiligo, and control groups, respectively (P < 0.001). No significant association of P-selectin levels was observed with psoriasis severity; however, with increasing vitiligo severity, there was a significant increase in P-selectin levels (P < 0.001). CONCLUSION: Patients with skin diseases have raised P-selectin levels. Within skin diseases, inflammatory diseases such as psoriasis have higher P-selectin levels as compared to autoimmune diseases such as vitiligo. A significant association of P-selectin levels was observed with vitiligo severity but not with psoriasis severity.

Résumé Introduction:Le rôle et la fonction des niveaux de P-sélectine dans diverses maladies inflammatoires et à médiation immunitaire ont été établis. Si leur association avec des maladies inflammatoires de la peau telles que le vitiligo et le psoriasis doit être établie.Objectif:L'objectif L'objectif de cette étude était d'évaluer les niveaux de P-sélectine dans le psoriasis et le vitiligo et de comparer l'anthropo avec des témoins appariés sans maladie cutanée.Matériels et méthodes:L'étude a inclus un total de 90 sujets ­ 30 dans chaque groupe, des sujets de même âge et sexe atteints de psoriasis, de vitiligo. et contrôles sans maladie de peau. La gravité du psoriasis et du vitiligo a été évaluée à l'aide du Psoriasis Area and Severity Index et du Vitiligo. Scores de l'indice de notation de zone. Les niveaux de P-sélectine ont été évalués et comparés entre les groupes. Les niveaux de P-sélectine ont également été comparés aux gravité du psoriasis et du vitiligo. Des tests du chi carré et d'analyse de variance ont été utilisés pour comparer les données.Résultats:L'âge moyen des sujets était de 36,28 ± 11,80 ans. La majorité des sujets étaient des hommes (65,6 %). Les trois groupes ont été appariés en fonction de l'âge, du sexe et d'autres données démographiques. Les taux moyens de P-sélectine étaient respectivement de 610,43 ± 134,19, 292,52 ± 60,99 et 158,97 ± 34,76 ng/ml dans les patients atteints de psoriasis, de vitiligo et de contrôle. groupes, respectivement (P <0,001). Aucune association significative entre les taux de P-sélectine et la gravité du psoriasis n'a été observée; cependant, avec l'augmentation En cas de gravité du vitiligo, il y avait une augmentation significative des taux de P-sélectine ( P < 0,001).Conclusion:les patients atteints de maladies de peau ont augmenté la sélectine P les niveaux. Parmi les maladies de la peau, les maladies inflammatoires telles que le psoriasis ont des taux de sélectine P plus élevés que les maladies auto-immunes telles que comme le vitiligo. Une association significative des taux de P-sélectine a été observée avec la gravité du vitiligo mais pas avec la gravité du psoriasis.

Diabetes, glycemic profile and risk of vitiligo: A Mendelian randomization study.

BACKGROUD: Previous observational studies have shown that vitiligo usually co-manifests with a variety of dysglycemic diseases, such as Type 1 diabetes mellitus (T1DM) and Type 2 diabetes mellitus (T2DM). Mendelian randomization (MR) analysis was performed to further evaluate the causal association between fasting plasma glucose, glycosylated hemoglobin (HbA1c), T1DM, T2DM and vitiligo. MATERIALS AND METHODS: We used aggregated genome-wide association data from the Integrative Epidemiology Unit (IEU) online database of European adults vitiligo; HbA1c data were from IEU. Fasting blood glucose data were obtained from the European Bioinformatics Institute (EBI). T1DM and T2DM data were from FinnGen. We used bidirectional two-sample and multivariate MR analyses to test whether dysglycemic measures (fasting blood glucose, HbA1c), diabetes-related measures (T1DM, T2DM) are causatively associated with vitiligo. Inverse variance weighting (IVW) method was used as the main test method, MR-Egger, Weighted mode and Weighted median were used as supplementary methods. RESULTS: We found no statistically significant evidence to support a causal association between dysglycemic traits and vitiligo, but in the correlation analysis of diabetic traits, our data supported a positive causal association between T1DM and vitiligo (p = 0.018). In the follow-up multivariate MR analysis, our results still supported this conclusion (p = 0.016), and suggested that HbA1c was not a mediator of T1DM affecting the pathogenesis of vitiligo. No reverse causality was found in any of the reverse MR Analyses of dysglycemic traits and diabetic traits. CONCLUSIONS: Our findings support that T1DM is a risk factor for the development of vitiligo, and this conclusion may explain why the co-presentation of T1DM and vitiligo is often seen in observational studies. Clinical use of measures related to T1DM may be a new idea for the prevention or treatment of vitiligo.

Circulating immune cells and vitiligo: a bidirectional two-sample Mendelian randomization study.

Background: The pathogenesis of vitiligo remains elusive. Emerging evidence suggests that vitiligo is an immune-mediated disorder, in which a plethora of immune cells play pivotal roles. However, the association between circulating immune cells and vitiligo continues to be enigmatic. Materials and methods: We extracted single nucleotide polymorphisms (SNPs) associated with immune circulating cells at a genome-wide significance level from the BLOOD CELL CONSORTIUM's genome-wide association study (GWAS) dataset. Summary data for 385,801 cases of vitiligo were obtained from a large-scale Finnish genome-wide association study (ncases=292, ncontrols=385,509). The inverse variance weighted (IVW) method was employed as the primary analytical approach for Mendelian randomization (MR) analysis. Additionally, heterogeneity was assessed using Cochran's Q value, and horizontal pleiotropy was evaluated using MR-Egger Mendelian Randomization Pleiotropy RESidual Sum and Outlier and leave-one-out analyses. Results: The risk of vitiligo was found to increase with the elevation of 4 circulating immune cells, as evidenced by the odds ratios (ORs) and 95% confidence intervals (CIs): basophils (OR=1.81; 95% CI: 1.01-3.24, p=0.0450), monocytes (OR=1.67; 95% CI: 1.23-2.26, p=0.0009), eosinophils (OR=1.78; 95% CI: 1.22-2.59, p=0.0028), and neutrophils (OR=1.65; 95% CI: 1.08-2.54, p=0.0208). After removing outliers, the sensitivity analysis of the above indicators did not show heterogeneity and pleiotropy. Conclusion: Our findings illuminate the association between circulating immune cells and vitiligo, offering insights that could guide clinical practices in the treatment of vitiligo.

Assessment of serum granulysin and cathepsin-L levels in vitiligo patients.

OBJECTIVE: Cellular and humoral immunity plays a role in the pathogenesis of vitiligo. T lymphocytes and natural killer cells involved in cellular immunity carry out their cytotoxic activities through perforin/granzyme-dependent granule exocytosis, in which granulysin and cathepsin-L are also involved. The aim of this study was to investigate the possible role of serum granulysin and cathepsin-L in the etiopathogenesis of vitiligo and their association with disease activity and severity. METHODS: This randomized, prospective case-control study was conducted with 46 vitiligo patients admitted to the hospital for vitiligo between January and November 2021 and 46 healthy volunteers of similar age and gender. Serum levels of granulysin and cathepsin-L were measured by the enzyme-linked immunosorbent assay method. RESULTS: The mean serum levels of granulysin and cathepsin-L were statistically significantly higher in vitiligo patients compared with the control group (p=0.048 and p=0.024, respectively). There was no statistically significant correlation between serum granulysin and serum cathepsin-L levels and disease severity in the patient group (r=0.30, p=0.062 and r=0.268, p=0.071, respectively). Disease activity also showed no significant association with serum granulysin and cathepsin-L levels (p=0.986 and p=0.962, respectively). CONCLUSION: Although granulysin and cathepsin-L are molecules involved in the pathogenesis of vitiligo, the use of these molecules may not be helpful in assessing disease activity and severity. It may be helpful to conduct comprehensive and prospective studies to find new molecules to fill the gap in this area.

Roles of blood metabolites in mediating the relationship between vitiligo and autoimmune diseases: Evidence from a Mendelian randomization study.

OBJECTIVE: This study employed Mendelian Randomization (MR) to investigate the causal relationship between genetic susceptibility to vitiligo and the risk of various autoimmune diseases, along with the mediating role of blood metabolites. METHODS: We performed two-sample MR analyses using aggregated genome-wide association studies (GWAS) data on 486 blood metabolites, vitiligo, and nine autoimmune diseases to investigate blood metabolites' causal effects on the susceptibility of vitiligo and the associations of vitiligo with nine autoimmune comorbidities. We also applied multivariable MR to unravel metabolites by which vitiligo influences the pathogenesis of autoimmune diseases. RESULTS: Our findings indicate that vitiligo amplified the risk of several autoimmune diseases, including rheumatoid arthritis (OR 1.17; 95 % CI 1.08-1.27), psoriasis (OR 1.10; 95 % CI 1.04-1.17), type 1 diabetes (OR 1.41; 95 % CI 1.23-1.63), pernicious anemia (OR 1.23; 95 % CI 1.12-1.36), autoimmune hypothyroidism (OR 1.19; 95 % CI 1.11-1.26), alopecia areata (OR 1.22; 95 % CI 1.10-1.35), and autoimmune Addison's disease (OR 1.22; 95 % CI 1.12-1.33). Additionally, our analysis identified correlations with vitiligo for 14 known (nine risk, five protective) and seven uncharacterized serum metabolites. After adjusting for genetically predicted levels of histidine and pyruvate, the associations between vitiligo and these diseases were attenuated. CONCLUSIONS: We substantiated vitiligo's influence on susceptibility to seven autoimmune diseases and conducted a thorough investigation of serum metabolites correlated with vitiligo. Histidine and pyruvate are potential mediators of vitiligo associated with autoimmune diseases.By combining metabolomics with genomics, we provide new perspectives on the etiology of vitiligo and its immune comorbidities.

Expression patterns of long non-coding RNAs in peripheral blood mononuclear cells of non-segmental vitiligo.

OBJECTIVE: We explored the patterns of long non-coding RNA (lncRNA) expression in peripheral blood mononuclear cells (PBMCs) from patients with non-segmental vitiligo. METHODS: We used high-throughput RNA sequencing technology to generate sequence data from five patients with non-segmental vitiligo alongside five normal healthy individuals, and then performed bioinformatics analyses to detect the differential expression of lncRNA in PBMCs. Gene Ontology (GO) and pathway analyses were performed for functional annotation, and quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify gene expression. Target miRNAs and mRNAs of differentially expressed lncRNAs were predicted using bioinformatics analysis. RESULTS: A total of 292 lncRNAs were differentially expressed in non-segmental vitiligo (fold change ≥ 2.0, P < .05), of which 171 were upregulated and 121 were downregulated. Six differentially expressed lncRNAs were selected, namely ENST00000460164.1, ENST00000393264.2, NR-046211.1, NR-135491.1, NR-135320.1, and ENST00000381108.3, for validation by qRT-PCR. The results showed that ENST00000460164.1 and NR-046211.1 were highly expressed in PBMCs of non-segmental vitiligo. An lncRNA-miRNA-mRNA network containing two lncRNAs, 17 miRNAs, and 223 mRNAs was constructed. CONCLUSION: Our results revealed patterns of differentially expressed lncRNAs in the PBMCs of non-segmental vitiligo individuals. ENST00000460164.1, and NR-046211.1 may be potential biomarkers and drug targets for the treatment of non-segmental vitiligo.

Can monocyte to HDL cholesterol ratio and monocyte to lymphocyte ratio be markers for inflammation and oxidative stress in patients with vitiligo? A preliminary study.

Both systemic inflammation and oxidative stress play crucial roles in the pathogenesis of vitiligo. In recent studies, monocyte to high-density lipoprotein cholesterol ratio (MHR), monocyte to lymphocyte ratio (MLR), neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), mean platelet volume (MPV) and plateletcrit (PCT) have been shown to reflect inflammation and oxidative stress in chronic inflammatory and autoimmune diseases. In this study, we aimed to investigate the hematological and inflammatory parameters in patients with vitiligo and to evaluate their possible relationship with disease severity. The parameters including MHR, MLR, NLR, PLR, MPV, and PCT were retrospectively investigated in patients with vitiligo and healthy controls. Disease severity was evaluated using the vitiligo extent tensity index (VETI) score. A total of 180 patients with vitiligo, and age-gender-matched 180 healthy controls were enrolled in the study. MHR, MLR, PLR, PCT values were found to be significantly higher in patients with vitiligo (p < 0.05). MPV and NLR values showed no statistically significant difference between the two groups. A positive correlation was also detected between MHR and MLR values, disease duration, and VETI score (p < 0.05). We suggest that MHR and MLR can be used as markers of inflammation and oxidative stress in patients with vitiligo. Both markers may also reflect disease severity.

Serum levels of miRNA-21-5p in vitiligo patients and effects of miRNA-21-5p on SOX5, beta-catenin, CDK2 and MITF protein expression in normal human melanocytes.

BACKGROUND: Epigenetics of vitiligo was evaluated in few studies. In particular, the role of miR-21, a microRNA involved in various processes, including melanogenesis, was never investigated. OBJECTIVE: Evaluation of serum levels of miR-21-5p in vitiligo patients and miR-21-5p effects on melanogenesis. METHODS: We measured serum levels of miR-21-5p in 40 patients affected by nonsegmental vitiligo and 40 sex- and age-matched healthy controls. Next, normal human melanocytes were transfected with miR-21-5p to study the effects of this microRNA, which targeted some proteins involved in melanogenesis pathway like SOX5, beta-catenin, cyclin-dependent kinase 2 (CDK2), and MITF. RESULTS: The expression of miR-21-5p in vitiligo patients was 3.6-4454.4 fold (mean 990.4 ± 1397.9) higher than in controls. The relative expression of miR-21-5p was directly and significantly correlated with disease severity, defined by VASI (Vitiligo Area and Severity Index) score (Rho = 0.89, p = 10-7), but not other individual or clinical characteristics. In the second part of the study, a significant reduction of SOX5, beta-catenin and CDK2 protein expression and increase of MITF protein expression was observed in cultured melanocytes after 24 h trasfection with miR-21-5p. CONCLUSION: According to literature, miR-21-5p upregulation and consequent SOX5 downregulation should upregulate melanogenesis, while vitiligo is characterized by skin depigmentation. Our results suggest that current knowledge of the pathogenesis of vitiligo is probably incomplete. Clinical manifestations could result from an altered balance between metabolic pathways with contrasting effects. In this view, miR-21-5p upregulation might be a tentative compensation mechanism. Further studies appear necessary to confirm and better understand our results and their importance.

Differentially expressed microRNAs in peripheral blood mononuclear cells of non-segmental vitiligo and their clinical significance.

BACKGROUND: Vitiligo is a frequent acquired depigmentation skin disease due to a loss of melanocytes. This study sought to characterize the expression pattern of microRNA (miRNA) in the peripheral blood mononuclear cells (PBMCs) of non-segmental vitiligo (NSV) patients. We also screened for molecular markers that can be used to evaluate the clinical stages of NSV. METHODS: The miRNA expression profile in the PBMCs of four patients with progressive NSV and four healthy controls was determined using high-throughput RNA sequencing. The divergently expressed miRNA was verified via qRT-PCR in 26 progression, 26 stable NSV, and 26 healthy controls. RESULTS: Our findings posited that 323 miRNAs were differentially expressed in the PBMCs of NSV patients. The top 10 up-regulated miRNAs in patients were hsa-miR-335-5p, hsa-miR-20a-5p, hsa-miR-514a-3p, hsa-miR-144-5p, hsa-miR-450b-5p, hsa-miR-369-3p, hsa-miR-101-3p, hsa-miR-142-5p, hsa-miR-19b-3p, and hsa-miR-340-5p. The top 10 down-regulated miRNAs in patients were hsa-miR-4443, hsa-miR-1248, hsa-miR-6859-3p, hsa-miR-668-3p, hsa-miR-7704, hsa-miR-323a-5p, hsa-miR-1237-3p, hsa-miR-3127-3p, hsa-miR-6735-3p, and hsa-miR-127-3p. The expressions of hsa-miR-20a-5p in PBMCs of progressive and stable NSV were remarkably elevated relative to the healthy controls. In the characteristics curve analysis of hsa-miR-20a-5p for differentiating progressive and stable NSV from normal subjects in PBMCs, the area under curve (AUC) was 0.92 and 0.81. Compared with patients in stable NSV, the hsa-miR-20a-5p was markedly increased in PBMCs of progressive NSV patients, and the AUC was 0.81. CONCLUSION: Our results showed that divergently expressed miRNAs contribute to the pathogenesis of NSV and that hsa-miR-20a-5p can be applied as a biosignature for stage assessment in PBMCs of patients with NSV.

MicroRNA­21­5p protects melanocytes via targeting STAT3 and modulating Treg/Teff balance to alleviate vitiligo.

Vitiligo (VIT) is caused by loss and degradation of functional epidermal melanocytes. Studies have indicated that melanocyte destruction may be associated with an imbalance between regulatory T cells (Treg cells) and effector T cells (Teff cells). The current study aimed to investigate the molecular mechanism through which Treg/Teff balance affects VIT pathogenesis. To explore this, peripheral blood mononuclear cells were isolated from patients with VIT and healthy individuals. The present study revealed that the proportions of CD4+ T cells, Treg cells and T helper 1 (Th1) cells were decreased in patients with VIT, but those of Teff cells (Th17 and Th22 cells) were increased; additionally, Foxp3 expression was decreased, but the expression levels of interferon­Î³, interleukin (IL)­17A and IL­22 were increased. Furthermore, in patients with VIT, microRNA (miR)­21­5p expression was decreased, while that of STAT3 was increased. Further in vitro experiments in CD4+ T cells revealed that STAT3 was targeted by miR­21­5p. Functional analysis further indicated that miR­21­5p overexpression in Th17­polarized CD4+ T cells decreased the proportion of Teff cells and associated cytokines, such as IL­17A and IL­22, but increased the proportion of Treg cells and Foxp3. However, the effects of miR­21­5p overexpression were partly reversed by STAT3 overexpression. Increased apoptosis of melanocytes was detected after co­culture with Th17­polarized CD4+ T cells in the presence of a miR­21­5p mimic. However, this indirect effect of the miR­21­5p mimic on melanocytes was decreased via STAT3 overexpression. Therefore, miR­21­5p may protect melanocytes via targeting STAT3 and regulating Treg/Teff balance. The current findings may provide a possible treatment method for managing VIT.

Serum level of S100B in vitiligo patients: Is it a marker of disease activity?

BACKGROUND: Vitiligo is a chronic depigmentary skin disorder, characterised clinically by the development of white macules and or patches caused by loss of epidermal melanocytes. S100B is a dual function protein released from epidermal melanocytes in response to injury. It considered a possible marker of disease activity in both malignant melanoma and vitiligo. AIM OF THE STUDY: To estimate the serum level of S100B level in vitiligo patients and correlate its level with disease activity and various disease parameters. PATIENTS AND METHODS: Sixty vitiligo patients and 60 healthy volunteers as controls were included in the study. Vitiligo Area Severity Index (VASI) and Vitiligo Disease Activity (VIDA) scores were estimated for each patient. Quantitative assessment of S100B level using ELISA technique was done for all participants. RESULTS: S100B level was significantly correlated with the presence of vitiligo (P = 0.01), while it showed no correlation with the disease activity using VASI or VIDA scores. As regards the receiver operating characteristic (ROC) curve analysis of S100B for diagnosis and discrimination of vitiligo, serum S100B showed area under the curve (AUC) of 0.781 with 73.3% sensitivity and 80% specificity. CONCLUSION: The serum level of S100B was related to the presence of vitiligo, but its level did not show any relation to the disease activity using either VASI and VIDA scores or various disease parameters.

LRP1/CD91 is highly expressed in monocytes from patients with vitiligo - even after repigmentation.

Vitiligo pathophysiology is mediated by antigen-specific cytotoxic T cells. Environmental stressors cause susceptible melanocytes to secrete damage-associated molecular patterns (DAMPs). DAMPs are recognized by receptors such as the endocytic low-density lipoprotein receptor-related protein (LRP1/CD91), expressed in antigen-presenting cells, which activate self-reactive CD8+ T cells, leading to melanocyte destruction. Within this response, interferon gamma triggers production of cytokine CXCL10, recruiting more activated T cells causing further melanocytic damage. We hypothesized that expression of LRP1/CD91 was higher in vitiligo patients compared to non-vitiligo individuals. And further that levels/expression of CXCL10 in plasma were linked to disease severity. We enrolled forty individuals in this study: 18 patients with vitiligo and 22 healthy volunteers. We assessed LRP1/CD91 expression and plasma CXCL10 in patients with vitiligo and healthy volunteers. Additionally, vitiligo patients received combined treatment for 16 weeks following which the said parameters were reassessed. Vitiligo Area Scoring Index was calculated before and after treatment for these patients. Analysis of LRP1/CD91 MFI values in monocytes from vitiligo patients showed high surface levels of LRP1/CD91 than from healthy volunteers (10.50 ± 0.77 vs. 6.55 ± 0.77 MFI units, p < 0.001). This expression did not change after treatment. Plasma levels of CXCL10 were higher in vitiligo patients than healthy volunteers (93.78 ± 7.73 vs. 40.17 ± 6.25 pg/ml). The patients with a good clinical response to treatment had a parallel reduction in plasma CXCL10 levels (105.8 ± 18.44 vs. 66.13 ± 4.87 pg/ml) before and after treatment. LRP1/CD91 expression may reflect susceptibility to vitiligo. Plasma levels of CXCL10 can represent a biomarker for monitoring treatment response. LRP1 and CXCL10 may represent therapeutic targets.

Increased level of cathelicidin (LL-37) in vitiligo: Possible pathway independent from vitamin D receptor gene polymorphism.

Vitiligo is a multifactorial skin disease with established role of genetics and autoimmunity in its pathogenesis. Vitamin D receptor (VDR) polymorphisms have been suggested to correlate with risk of vitiligo in some ethnic populations. On the other hand, cathelicidin, one of the innate immune system components, has a role in development of some chronic skin diseases and VDR regulates the expression of cathelicidin. We aimed to determine the plasma level of cathelicidin and its association with the VDR gene polymorphisms as well as plasma vitamin D level in patients with vitiligo. Ninety vitiligo patients and 90 non-vitiligo controls participated in this study. Blood levels of 25(OH) vitamin D and cathelicidin were determined with ELISA. Genotyping for VDR polymorphisms (ApaI, TaqI, FokI and BsmI) was done with RFLP-PCR method. Mean blood level of cathelicidin was significantly higher in vitiligo patients as compared to controls (P < .0001). Mean blood level of vitamin D was significantly lower in patients than controls (P = .01). Statistically significant differences were not observed for both genotype and allele frequencies of BsmI, ApaI and TaqI polymorphisms. There was a borderline increased risk of vitiligo in over-dominant model of FokI polymorphism with OR = 1.8 and P = .051. Our findings was suggestive of the potential role of cathelicidin in the pathogenesis of vitiligo; however, future evaluations are needed to determine its precise mechanism. Genetic study of VDR gene polymorphism was suggestive of increased risk of vitiligo in association with a FokI polymorphism in Iranian population.

Macrophage inhibitory factor (MIF) gene polymorphisms are associated with disease susceptibility and with circulating MIF levels in active non-segmental vitiligo in patients from western Mexico.

BACKGROUND: The macrophage migration inhibiting factor (MIF) is a protein that promotes the activation of immune cells and the production of other proinflammatory cytokines such as TNF-α, IL-1ß, and IFN-γ, which have proposed to play an essential role in the pathogenesis of vitiligo. The study aimed to assess the association between MIF polymorphisms (-794 CATT5-8 and -173 G>C), MIF in situ expression, and MIF serum concentrations with susceptibility and disease activity in patients with non-segmental vitiligo (NSV) from western Mexico. METHODS: The study included 111 patients with NSV and 201 control subjects. Genotyping was performed by conventional PCR (-794 CATT5-8 ) and PCR-RFLP (-173 G>C) methods. MIF mRNA expression was quantified by real-time PCR and MIF serum concentrations were determined by ELISA kit. Histopathological samples were analyzed by automated immunohistochemistry. RESULTS: The MIF polymorphisms were associated with NSV susceptibility. Serum concentrations of MIF were higher in patients with active NSV and correlated negatively with the years of evolution. The depigmented skin from patients with active vitiligo showed a high expression of MIF. CONCLUSION: MIF polymorphisms increase the risk of NSV in the western Mexican population. The serum concentrations of MIF and in situ expression are associated with active NSV.

Selenium Level in Patients with Vitiligo: A Meta-Analysis.

BACKGROUND: It has been reported that deficiency of selenium can cause autoimmune disease. This meta-analysis was aimed at evaluating whether there exits an association between selenium level and vitiligo. METHODS: A comprehensive search was conducted on PubMed, Embase, China National Knowledge Infrastructure (CNKI), Wanfang Med Online, and China VIP databases from the inception to February 12, 2019. The main outcome was the standardized mean difference (SMD) with 95% confidence interval (CI) in serum selenium level between vitiligo patients and healthy controls. RESULTS: A total of 8 studies with 305 vitiligo patients and 6156 healthy controls were included in this meta-analysis. The results showed that there was no significant difference in selenium level between vitiligo patients and healthy controls (SMD = 0.481, 95%CI = -0.642 to 1.604, Z = 0.840, P > 0.05). Further subgroup analysis stratified by area revealed that Asian vitiligo patients had decreased selenium level, while that finding was not observed in Caucasian patients (Asian: SMD = -0.303, 95%CI = -0.603 to -0.004, P < 0.05; Caucasian: SMD = 0.957, 95%CI = -0.752 to 2.665, P > 0.05). CONCLUSIONS: Although overall selenium level was similar between vitiligo patients and health controls, subgroup analysis showed decreased levels of selenium in Asian vitiligo patients. It may suggest a clinical tailored administration of selenium supplementation in Asian vitiligo patients.

Serum level of antioxidant vitamins and minerals in patients with vitiligo, a systematic review and meta-analysis.

BACKGROUND: Antioxidant status is considered as important factor in the pathogenesis of vitiligo. However, there are controversial findings about serum status of antioxidants in vitiligo patients. The purpose of this study was to systematically review the evidences comparing the serum levels of antioxidant vitamins and minerals between vitiligo patients and controls, and performing meta-analysis of the results. METHODS: A comprehensive search was performed for studies comparing the serum status of antioxidant vitamins and minerals using following databases since inception up to 30 April 2020; PubMed, EMBASE, Scopus, and Web of Science. Data extraction was done by two independent reviewers. The data was pooled for serum level of each antioxidant comparing between vitiligo and control groups. RESULTS: Thirteen studies were included in this systematic review. The serum level of vitamin A, C, E, selenium, zinc and copper were compared between vitiligo patients and controls in these studies. Eleven studies including 570 vitiligo cases and 580 controls were included in the meta-analysis. Serum vitamin A and copper level in vitiligo patients were only evaluated in single studies and not included in meta-analysis. Based on fixed effect model, there were no statistical difference between two groups regarding serum vitamin C (OR = 1.17, 95 % CI, 0.74-1.84, P = 0.495), and vitamin E (OR = 0.61, 95 % CI, 0.30-1.25, P = 0.180). Higher serum zinc can decrease the risk of vitiligo based on sensitivity analysis of the results. (OR = 0.29, 95 % CI 0.15-0.54, P < 0.001). Higher serum selenium level significantly increased the risk of vitiligo (OR = 4.31, 95 % CI, 2.72-6.81, P < 0.001). Vitamin A was not significantly different in two reported groups (6.35 ±â€¯1.53 vs 6.77 ±â€¯1.46 µg/mL, P > 0.05). Copper was significantly higher in vitiligo patients compared to controls (129 ±â€¯33 vs 99 ±â€¯19 µg /100 mL, P = 0.002). CONCLUSION: The current meta-analysis of data on serum level of most studied antioxidants (vitamin C, vitamin E, zinc and selenium) in patients suffering vitiligo showed that higher serum selenium (OR = 4.31) and lower zinc level (OR = 0.29) can increased the risk of vitiligo. Potential mechanism associated with preventive effects of zinc and the depigmentation effect of selenium should be more elucidated in further studies.