Multiple gene-drug prediction tool reveals Rosiglitazone based treatment pathway for non-segmental vitiligo

Vitiligo is a skin disease characterized by selective loss of melanocytes, which seriously affects the appearance and causes great psychological stress to patients. In this study, we performed a comprehensive analysis of two vitiligo microarray datasets from the GEO database using bioinformatics tools to identify 297 up-regulated mRNAs and 186 down-regulated mRNAs, revealing important roles for pathways related to melanin synthesis, tyrosine metabolism, and inflammatory factors, such as "PPAR signaling pathway", "tyrosine metabolism", "nonalcoholic fatty liver disease (NAFLD) pathway", "melanogenesis", and "IL-17 signaling pathway". Combining the Search Tool for Interacting Chemicals (STITCH) database 5.0 and the drug-gene interaction database 3.0 (DGIdb), we identified that the PPAR-γ agonist rosiglitazone may promote melanin synthesis via EDNRB. Next, we investigated the mechanism of rosiglitazone and PPAR-γ pathway in promoting melanin production. Consistent with the results of bioinformatics analysis, the expression levels of PPAR-γ, EDNRB, and TYR were significantly reduced in human non-segmental vitiligo skin along with the reduction of MITF, a key gene for epidermal melanogenesis. Meanwhile, rosiglitazone increased melanin synthesis capacity in melanocytes and zebrafish by activating PPAR-γ and upregulating TYR, TYRP-1, and TYRP-2. Conversely, treatment of melanocytes with the PPAR-γ antagonist GW resulted in inhibition of melanin synthesis and expression of melanin-related factors. At the same time, simultaneous treatment of rosiglitazone with GW reversed the inhibitory effect of GW on melanin synthesis. In this study, we identified that rosiglitazone, an important insulin sensitizer, promotes melanin synthesis in melanocytes by increasing PPAR-γ activity and upregulating the expression levels of EDNRB and TYR. These findings may provide new ideas for exploring the pathogenesis and potential therapeutic targets of non-segmental vitiligo.

Vitamin D and Interleukin-17: Are These Serum Biomarkers Useful in Non-Segmental Vitiligo? A Case Control Study from Central India

Non-segmental vitiligo (NSV) is an autoimmune disorder due to the destruction of melanocytes, where cytokines like interleukin 17 (IL-17) and biomolecules like vitamin D play a theoretical role in pathogenesis. Previous studies in this regard yielded inconsistent results. This study aimed to compare the serum levels of IL-17 and vitamin D between NSV patients and healthy controls and to know the association of these biomarkers with disease activity and extent. This was a case-control study including adult patients with NSV and age and gender-matched healthy controls. Cases and controls with conditions likely to alter the serum levels of IL-17 and vitamin D were excluded. Serum levels of IL-17 were estimated by ELISA and vitamin D levels by chemiluminescence assay. 42 adult patients of NSV and 42 age and sex-matched healthy controls were recruited over a period of eighteen months. The mean value of serum vitamin D levels in the control group was 19.053 ± 5.340 ng/ml, whereas in the case group, it was 17.336 ± 6.931 ng/ml (P > 0.05). The mean value of serum IL-17 levels in the control group was 199.824 ± 51.244 pg/ml and 213.566 ± 69.018 pg/ml in the case group (P > 0.05). These molecules did not show any association with the disease activity and extent. In contrast to the previous studies, we could not establish the role of IL-17 in the pathogenesis of vitiligo. Furthermore, we could not find any association between vitamin D and vitiligo in our study, even though there is an inconsistent association between the two in the available literature.

Whole Exome Sequencing Reveals Clustering of Variants of Known Vitiligo Genes in Multiplex Consanguineous Pakistani Families

Vitiligo is an autoimmune complex pigmentation disease characterized by non-pigmented patches on the surface of the skin that affect approximately 0.5-2% population worldwide. The exact etiology is still unknown; however, vitiligo is hypothesized to be a multifactorial and genetically heterogeneous condition. Therefore, the current study is designed to investigate the anthropometric presentation and genetic spectrum of vitiligo in fifteen consanguineous Pakistani families. The clinical evaluation of participating individuals revealed varying degrees of disease severity, with 23 years as the average age of disease onset. The majority of the affected individuals had non-segmental vitiligo (NSV). Whole exome sequencing analysis revealed clustering of rare variants of known vitiligo-associated genes. For instance, in the affected individuals of family VF-12, we identified three novel rare variants of PTPN22 (c.1108C>A), NRROS (c.197C>T) and HERC2 (c.10969G>A) genes. All three variants replaced evolutionarily conserved amino acid residues in encoded proteins, which are predicted to impact the ionic interactions in the secondary structure. Although various in silico algorithms predicted low effect sizes for these variants individually, the clustering of them in affected individuals increases the polygenic burden of risk alleles. To our knowledge, this is the first study that highlights the complex etiology of vitiligo and genetic heterogeneity in multiplex consanguineous Pakistani families.

A non-inferiority randomized controlled clinical trial comparing Unani formulations and PUVAsol in non-segmental vitiligo

OBJECTIVES

Greco-Arab medicine is an ancient system of medicine with greater treasure on therapeutics of vitiligo. The trial Unani formulations have not been scientifically explored for their safety and efficacy, but have been repeatedly prescribed by the great Unani physicians in the management of Baraṣ (vitiligo). Hence, these interventions were selected for the trial.

METHODS

In this randomized, controlled, open-label clinical trial, 82 participants with non-segmental vitiligo aged 18-40 years were block randomized to either receive Unani interventions or control for 16 weeks. Out of 82 participants, 42 were randomized to the Unani group and 40 were randomized to the control group. The primary outcome measure was change in vitiligo area scoring index (VASI), which was assessed on weeks 4, 8, 12 and 16. The secondary outcome measures included the patient's global assessment on VAS and investigator's global assessment based on photographic evaluation at baseline and after the treatment. Safety parameters included hemogram, LFTs, RFTs, CXR, ECG, urine, and stool examinations, which were evaluated at baseline and after the treatment.

RESULTS

The per-protocol analysis was done on 30 participants in each group and the response in Unani group was not inferior to those receiving control group. The mean ± SD of vitiligo area scoring index (VASI) decreased from 4.09 ± 2.87 and 5.50 ± 5.73 at baseline to 3.13 ± 2.20 and 4.29 ± 4.95 at the end of the trial in both the Unani and control groups respectively.

CONCLUSIONS

The study inferred that both the interventions are equally effective and well-tolerated in patients with non-segmental vitiligo.

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.

Efficacy of NB-UVB in Progressive Versus Non-Progressive Non-Segmental Vitiligo: A Prospective Comparative Study

Introduction:

Narrow-band (NB) ultraviolet B (UVB) phototherapy has been shown to halt disease progression in vitiligo, but whether there is any difference in the response to NB-UVB seen in patients with progressive vitiligo versus non-progressive vitiligo has not been evaluated.

Objectives:

To evaluate the effect of NB-UVB on progressive versus non-progressive non-segmental vitiligo.

Study Design:

Prospective observational comparative study.

Duration:

April 2016-November 2017.

Methods:

Adult patients having non-segmental vitiligo involving 2-50% body surface area were divided into two subsets; patients developing >5 lesions in the last 1 month or >15 lesions in the last 3 months (progressive vitiligo, Group I) and patients with static disease for the last 6 months (non-progressive vitiligo, Group II). Both groups were treated with NB-UVB for 6 months (26 weeks) cumulatively and its efficacy in halting disease progression, re-pigmentation, side effects and psychosocial impact were evaluated.

Results:

Nineteen out of 24 patients with progressive vitiligo had arrest of disease progression. Rest five patients developed lesions at a slower pace. Group II had earlier onset of re-pigmentation, while Group I had more NB-UVB fluence (34.73 J/cm² vs 25.2 J/cm², P value = 0.034), more time for the fluence to be fixed (P value = 0.001) and more pruritus (P value = 0.001).

Conclusions:

NB-UVB has the potential to halt disease progression in some patients with progressive vitiligo; but is associated with more total NB-UVB fluence and time taken for fixing it. Progressive vitiligo patients have more pruritus as compared to patients with non-progressive vitiligo.

Efficacy of topical tacrolimus 0.03% monotherapy in the treatment of non-segmental vitiligo: a randomized, controlled trial

BACKGROUND

Topical tacrolimus is increasingly used nowadays in the treatment of vitiligo.

OBJECTIVE

We evaluated therapeutic outcomes of tacrolimus 0.03% in non-segmental vitiligo (NSV).

PATIENTS AND METHODS

Sixty-three patients with NSV were divided into groups A and B. Group A received 0.03% tacrolimus ointment (n = 31) and group B received 1% hydrocortisone acetate ointment (n = 32) for 24 weeks. Vitiligo area and severity index (VASI) and repigmentation rates were determined at baseline and 4-week intervals.

RESULTS

In group A, 24-week VASI [0.5 (0.3, 1.95)] was significantly lower than baseline VASI [0.75 (0.5, 2.1); p = 0.030]. In group B, 24-week VASI [0.75 (0.4, 2.3)] was not significantly different from baseline VASI [0.73 (0.4, 2.1); p = 0.111]. Repigmentation was observed in 14/31 (45.2%) of patients in group A versus 0/32 (0.0%) in group B (p < 0.001). Repigmentation was graded as poor in 6/31 (19.4%), fair in 4/31 (12.9%), good in 1/31 (3.2%), and excellent in 3/31 (9.7%).

CONCLUSION

Repigmentation was achieved in 45% of patients with NSV following treatment with tacrolimus 0.03% monotherapy for 24 weeks. Tacrolimus-induced repigmentation is more likely in patients with vitiligo vulgaris, head and neck lesions, skin phototype III, and young age.

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.

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‐1β, 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 CATT_5‐8 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 CATT_5‐8) 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.

Immunophenotype of circulatory T-helper cells in patients with non-segmental vitiligo

Introduction

Non-segmental vitiligo (NSV) is an immune-mediated skin depigmentation disease. Cytokine-mediated interaction between T lymphocytes and melanocytes leads to death of melanocytes, causing a defect in melanin synthesis and thereby depigmentation. There is an increased population of T-helper cells in the skin lesions as well as in the peripheral circulation in NSV. However, the relative percentage of each T-cell phenotype in the disease pathogenesis is rarely studied.

Aim

To study the immunophenotype of the different T-helper/Treg cell subsets in patients with NSV, in comparison to healthy controls.

Material and methods

A total of 80 patients with NSV and eighty age- and gender-matched healthy controls were recruited in this cross-sectional study. Disease activity was determined by vitiligo index of disease activity (VIDA) scoring. Peripheral blood mononuclear cells were separated by Ficoll-Paque density centrifugation, and T-cell immunophenotyping was done by flow cytometric analysis.

Results

In patients with NSV, we observed an imbalance in T-cell immunophenotype, characterized by an increase in Th1 (p < 0.0001) and Th17 cells (p = 0.01). There is no difference in relative percentage of Th2/Treg cells, as compared to the healthy controls (p > 0.05).

Conclusions

There is a significant immune-dysregulation with a preponderance of circulatory Th1/Th17 phenotype in NSV patients.

Serum Thyroid Hormone Antibodies Are Frequent in Patients with Polyglandular Autoimmune Syndrome Type 3, Particularly in Those Who Require Thyroxine Treatment

Polyglandular autoimmune syndrome (PAS) type 3 consists of autoimmune thyroid disease (AITD) coexisting with ≥1 non-thyroidal autoimmune disease (NTAID) other than Addison's disease and hypoparathyroidism. We evaluated the prevalence and repertoire of thyroid hormones antibodies (THAb) in PAS-3 patients. Using a radioimmunoprecipation technique, we measured THAb (T3IgM, T3IgG, T4IgM, and T4IgG) in 107 PAS-3 patients and 88 controls (patients with AITD without any NTAID). Based on the selective coexistence of AITD with one NTAID (chronic autoimmune gastritis, non-segmental vitiligo or celiac disease), patients were divided into group 1 (chronic autoimmune gastritis positive, n = 64), group 2 (non-segmental vitiligo positive, n = 24), and group 3 (celiac disease positive, n = 15). At least one of the four THAb was detected in 45 PAS-3 patients (42.1%) and 28 controls (31.8%, P = 0.14), with similar rates in the three PAS-3 groups. The rates of T3Ab, T4Ab, and T3 + T4Ab were similar in groups 1 and 2, while in group 3, T3Ab was undetected (P = 0.02). In PAS-3 patients, the rate of levothyroxine treatment was greater in THAb-positive patients compared to THAb-negative patients (76.7 vs. 56.1%, P = 0.03, RR = 1.4, 95% CI 1.03-1.81). Not unexpectedly, levothyroxine daily dose was significantly higher in group 1 and group 3, namely in patients with gastrointestinal disorders, compared to group 2 (1.9 ± 0.4 and 1.8 ± 0.3 vs. 1.5 ± 0.2 μg/kg body weight, P = 0.0005 and P = 0.004). Almost half of PAS-3 patients have THAb, whose repertoire is similar if chronic autoimmune gastritis or celiac disease is present. A prospective study would confirm whether THAb positivity predicts greater likelihood of requiring levothyroxine treatment.

Differential expression analysis of miRNA in peripheral blood mononuclear cells of patients with non-segmental vitiligo

Vitiligo is a common depigmentary skin disease that may follow a pattern of multifactorial inheritance. The essential factors of its immunopathogenesis is thought to be the selective destruction of melanocytes. As a new class of microregulators of gene expression, miRNA have been reported to play vital roles in autoimmune diseases, metabolic diseases and cancer. This study sought to characterize the different miRNA expression pattern in the peripheral blood mononuclear cells (PBMC) of patients with non-segmental vitiligo (NSV) and healthy individuals and to examine their direct responses to thymosin α1 (Tα1) treatment. The miRNA expression profile in the PBMC of patients with NSV was analyzed using Exiqon's miRCURY LNA microRNA Array. The differentially expressed miRNA were validated by real-time quantitative polymerase chain reaction. We found that the expression levels of miR-224-3p and miR-4712-3p were upregulated, and miR-3940-5p was downregulated in the PBMC. The common clinical immune modulator Tα1 changed the miRNA expression profile. Our analysis showed that differentially expressed miRNA were associated with the mechanism of immune imbalance of vitiligo and that Tα1 could play an important role in changing the expression of these miRNA in the PBMC of patients with NSV. This study provided further evidence that miRNA may serve as novel drug targets for vitiligo therapeutic evaluation.