Vitiligo, from Pathogenesis to Therapeutic Advances: State of the Art

Autologous skin cell suspension plus phototherapy in stable vitiligo: findings from a US economic model

INTRODUCTION

A cell harvesting device for preparing non-cultured autologous skin cell suspension (ASCS) at the point-of-care is FDA-approved for repigmentation of stable depigmented vitiligo lesions in patients 18 years and older. The pivotal RSVP trial showed ≥80% repigmentation at Week-24 in 36% of lesions treated with laser ablation, ASCS, and narrowband ultraviolet B phototherapy compared to 0% with phototherapy alone (p = 0.012). The objective of this analysis was to evaluate the potential economic impact of laser ablation plus ASCS with phototherapy versus phototherapy alone for repigmentation of stable vitiligo lesions from a US payer perspective.

METHODS

A 5-year decision-tree model was developed reflecting clinical pathways of adults with stable vitiligo lesions who had an inadequate response to prior topicals and phototherapy. Patients entering the model were treated with ASCS plus phototherapy or phototherapy alone and assessed for treatment response at Weeks-24 and 52 based on the RSVP trial's effectiveness endpoints. Durable response for Year-2 onwards was proxied by melanocyte-keratinocyte transplantation data. Model outcomes included per-patient total and incremental healthcare costs, treatment costs and total costs, cost per-patient per-month (PPPM), and cost per-patient per-year (PPPY). One-way sensitivity analyses assessed model result robustness.

RESULTS

The cumulative total per-patient cost for ASCS plus phototherapy increased from $28,177 to $92,779 between Year-1 and Year-5. Phototherapy alone increased from $21,146 to $101,518 over the same period. Compared to phototherapy alone, ASCS plus phototherapy incurred $7,030 more total per-patient cumulative costs in Year-1 and $8,738 less by Year-5 (-$146 PMPM; -$1,748 PPPY). Breakeven occurred between Years 2-3. Results were most sensitive to changes in ASCS response at Weeks-24 and 52 and healthcare costs.

CONCLUSION

Among adults with stable vitiligo with prior inadequate response to topicals or phototherapy, ASCS treatment may lead to lower all-cause direct medical costs over 5 years compared to phototherapy alone.

Combined tofacitinib citrate and 308-nm excimer laser treatment for vitiligo: a pilot study

BACKGROUND

Vitiligo is a clinically prevalent acquired skin disorder characterized by depigmentation. Currently, the therapeutic options for vitiligo are restricted, and numerous issues exist, such as a prolonged treatment course, unsatisfactory therapeutic efficacy, adverse reactions and a high propensity for recurrence after treatment cessation.

OBJECTIVES

To assess the safety and efficacy of combined treatment involving oral tofacitinib citrate (TC) and a 308-nm excimer laser (EL), with the aim of discovering a rapid and effective treatment approach to minimize the side-effects of various drugs.

METHODS

In total, 63 patients with progressive vitiligo and a Vitiligo Disease Activity Score of 4 from January 2022 to January 2024 were enrolled and divided into three groups. The three groups were: the TC combined with 308-nm EL and methylprednisolone treatment group (group 1); the TC and 308-nm EL treatment group (group 2); and the methylprednisolone alone treatment group (group 3). The treatment was continued for 24 weeks, and an assessment of therapy outcomes was performed.

RESULTS

When TC was combined with 308-nm EL and methylprednisolone treatment (group 1), the effect was more rapid than in the other two groups. When TC was combined with 308-nm EL (group 2), it had a more favourable treatment effect than that of methylprednisolone alone (group 3), despite having a slower onset of effect. After 24 weeks of treatment, there was no significant difference between group 1 and group 2 in terms of the total response rate or significant response. However, when only methylprednisolone treatment was applied, the effect was relatively slow and ineffective.

CONCLUSIONS

This study confirmed a rapid and effective treatment of vitiligo was achieved through a combination of TC and 308-nm EL. No serious adverse reactions were reported, and therefore this could potentially offer an optimal treatment plan for patients with vitiligo.

Beyond skin deep: exploring the complex molecular mechanisms and holistic management strategies of vitiligo

Vitiligo is a multifactorial skin disorder characterized by the progressive loss of pigmentation due to the destruction of melanocytes, affecting 0.5-2% of the global population. This condition not only impacts physical appearance but also has profound psychosocial effects on patients. In this review, various aspects of vitiligo are explored, including its clinical forms, epidemiology, and underlying mechanisms. Advances in research have identified key molecular pathways, such as Wnt/β-Catenin, JAK-STAT, and AhR signaling, which are essential for melanocyte survival and immune regulation. These pathways provide valuable insights into the disease's progression and potential treatment targets. Furthermore, the role of microbial imbalances in the gut and skin microbiomes, stress-related factors, and nutritional deficiencies in influencing the onset and progression of vitiligo is investigated. The potential of herbal treatments to stimulate repigmentation is also discussed. By presenting a comprehensive overview, this review aims to deepen the understanding of vitiligo's complex pathology and foster the development of effective therapeutic strategies to enhance patient care.

Identification of disease-specific gut microbial markers in vitiligo

There is a potential correlation between vitiligo and gut microbiota, although research in this area is currently limited. The research employed high-throughput sequencing of 16S rRNA to examine the gut microbiome in the stool samples of 49 individuals with vitiligo and 49 without the condition. The study encompassed four comparison groups: (1) DI (disease) group vs. HC (healthy control) group; (2) DI_m group (disease group of minors) vs. HC_m group (healthy control group of minors); (3) DI_a group (adult disease group) vs. HC_a group (adult healthy control group); (4) DI_m group vs. DI_a group. Research findings have indicated the presence of spatial heterogeneity in the gut microbiota composition between individuals with vitiligo and healthy controls. A significant reduction in gut microbiota diversity has been observed in vitiligo patients across both minors and adult groups. However, variations have been noted in the composition of disease-related differential microbial markers among different age groups. Specifically, Bacteroides and Parabacteroides have been identified as specific markers of the intestinal microbiota of vitiligo patients in both minor and adult groups. Correlative analyses have revealed a positive correlation of these two genera with the Vitiligo Area Scoring Index (VASI) and disease duration. It is noteworthy that there are no significant differences in diversity between the DI_m group and the DI_a group, with similarities in microbiota composition and functional characteristics. Nevertheless, correlative analyses suggest a declining trend in Bacteroides and Parabacteroides with increasing age. Individuals with vitiligo exhibit distinct features in their gut microbiome when contrasted with those in the healthy control group. Additionally, the microbial marker genera that show variances between patients and healthy controls vary among different age groups. Disease-specific microbial marker genera (Bacteroides and Parabacteroides) are associated with VASI, duration of the condition, and age. These findings are essential for improving early diagnosis and developing potential treatment strategies for individuals with vitiligo.

Treatment Advances in Vitiligo: An Updated Review

INTRODUCTION

Vitiligo is a common disorder of depigmentation caused by the progressive destruction of melanocytes that affects the skin, hair, and mucous membranes, clinically presenting as depigmented macules and leukotrichia. This condition, affecting millions of people worldwide, has a significant psychosocial burden on patients' quality of life, particularly in relation to skin colour. The etiopathogenesis of this disorder is obscure, but multiple factors contribute to the loss of melanocytes in the skin, like oxidative stress, inflammation, genetics, and autoimmunity. The treatment of vitiligo has been challenging over the past years, but recent developments in understanding the etiopathogenesis of the disease have paved the way for the development of more effective and promising therapeutic treatment options.

OBJECTIVE

The aim of this review was to provide an overview of the underlying mechanisms and highlight the latest advances in the treatment of vitiligo.

METHODOLOGY

This review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Metanalyses) guidelines. A comprehensive search of the literature was carried out through the PubMed electronic database from inception to 31 December 2023 using the following search terms "vitiligo" AND "JAK inhibitors", "vitiligo" AND "prostaglandin", " vitiligo" AND " afamelanotide", "vitiligo" AND "antioxidants", "vitiligo" AND "vitamin D3", "vitiligo" AND "statins", "vitiligo" AND "TNF-alpha", "vitiligo" AND "interleukin", "vitiligo" AND "light therapy". Two independent reviewers screened titles, abstracts, and full texts to select papers dealing with vitiligo and its treatment.

CONCLUSION

The advent of treatment modalities like Janus kinase inhibitors, prostaglandin analogues, antioxidants, TNF-α inhibitors, targeted phototherapy, and excimer lasers has revolutionized the therapeutic possibilities, offering a ray of hope to the individuals suffering from this devastating condition.

Dietary Interventions, Supplements, and Plant-Derived Compounds for Adjunct Vitiligo Management: A Review of the Literature

Vitiligo is a chronic autoimmune pigmentation disorder shaped by a complex interplay of genetic predispositions and environmental triggers. While conventional therapies-phototherapy, corticosteroids, and immunosuppressants-can be effective, their benefits are often partial and temporary, with recurrence common once treatment stops. As such, there is increasing interest in exploring complementary approaches that may offer a more sustainable impact. Emerging evidence suggests that macronutrient and micronutrient-level changes could be beneficial for managing progression and, in some cases, facilitating repigmentation. Antioxidant-rich foods, such as apples, green tea, Indian gooseberry, onions, and peppers, may help mitigate oxidative stress, while inflammatory foods, such as gluten and high-phenol nuts and berries, may exacerbate the condition. Certain supplements, including high-dose vitamin D, vitamin C, vitamin E, and selenium, may enhance phototherapy outcomes. Omega-3 and other unsaturated fatty acids, in addition to prebiotics and probiotics, are under active investigation for their roles in gut health and immune regulation. Notably, plant-derived compounds, i.e., Ginkgo biloba, have demonstrated promise in promoting repigmentation and managing disease progression. However, it must be emphasized that these nutritional interventions remain exploratory, and more research is needed to establish their efficacy, safety, and optimal usage before they can be recommended as part of a standard treatment regimen.

Short-term efficacy and safety of upadacitinib combined with 308 excimer light versus upadacitinib alone and 308 excimer light alone in patients with progressing facial vitiligo

Patients with progressing facial vitiligo who had been treated with upadacitinib, 308 nm excimer light and upadacitinib combined with 308 nm excimer light were selected for retrospective analysis and comparison of their efficacy and safety. Efficacy was evaluated using the Vitiligo Area Severity Index (VASI) and Dermatology Life Quality Index (DLQI) at baseline, after 8 weeks, and after 20 weeks. The progression of skin lesions was monitored through reflectance confocal microscopy (RCM), while adverse reactions were documented. In the combination treatment group, the average VASI at baseline was 0.875 ± 0.4111, which decreased to 0.56 ± 0.32 at week 8 and 0.23 ± 0.218 at week 20 of follow-up (F = 9.918, p = 0.001). RCM analysis indicated that cases achieving VASI100 showed restoration to normalcy regarding loss of integrity within the pigment ring in lesion areas. Although one patient experienced exacerbation of acne, this condition was manageable with topical medication. In contrast, the average VASI score in the 308 nm excimer light group prior to treatment was recorded at 0.908 ± 0.334; by week twenty, it further declined to an average of 0.495 ± 0.4196. The differences observed were statistically significant (F = 28.644, p < 0.001). For patients in the upadacitinib group, the initial average VASI score was noted as being 0.825 ± 0.34; by twenty weeks it averaged approximately 0.53 ± 0.33; however, these differences did not reach statistical significance (F = 2.87, p = 0.14). The efficacy of the combined treatment group was significantly superior compared to both other groups (F = 3.927, p = 0.026). In conclusion, upadacitinib combined with308nm excimer light represents an effective therapeutic option for progressive facial vitiligo and is associated with fewer adverse reactions as well as improved quality of life for patients.

Screening for Biomarkers Related to Pigmentation and Formation in Vitiligo

BACKGROUND

Vitiligo is an autoimmune skin disorder primarily characterized by the absence of melanocytes, leading to the development of white patches on the patient's skin. Narrowband Ultraviolet B (NB-UVB) therapy is among the most effective approaches for stimulating the reformation of hyperpigmentation. This treatment utilizes a narrow spectrum of NBUVB wavelengths ranging from 311 to 313 nm to irradiate the affected area, thereby preventing the destruction of migrating and proliferating melanocytes. Nevertheless, the molecular alterations occurring in both the hair follicle and the interfollicular epidermis during NB-UVB treatment remain unknown.

METHODS

In this study, we conducted a comprehensive analysis of the consistency of differentially expressed genes (DEGs) within the enrichment pathways both before and after NB-UVB treatment, utilizing a bioinformatics approach. Furthermore, we employed CYTOHUBBA and Random Forest algorithms to identify and sequence hub genes from the pool of DEGs. Following validation of these hub genes through ROC curve analysis, we proceeded to construct an interaction network between these hub genes, miRNA, and drugs. Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR) was used to further verify the difference in the expression of hub genes between the disease group and the control group.

RESULTS

Gene Set Enrichment Analysis of DEGs indicated strong associations with vitiligo in most pathways. Subsequently, we conducted Gene Ontology and Metascape enrichment analyses on the overlapping genes from DEGs. We identified key genes (COL11A1, IGFBP7, LOX, NTRK2, SDC2, SEMA4D, and VEGFA) within the Protein-Protein Interaction (PPI) network. We further explored potential drugs that could be used for the clinical treatment of vitiligo through the drug-hub gene interaction network. Finally, the results of RT-qPCR experiments demonstrated that the expression levels of the identified hub genes in both groups were consistent with the bioinformatics analysis results.

CONCLUSION

The hub genes obtained in this study may be a biomarker related to the development of vitiligo pigmentation. Our research not only contributes to a better understanding of the treatment mechanisms of vitiligo but also provides valuable insights for future personalized medical approaches and targeted therapies for vitiligo.

Low-Dose Baricitinib Plus Narrow-Band Ultraviolet B for the Treatment of Progressive Non-Segmental Vitiligo: A Prospective, Controlled, Open-Label Study

Vitiligo is a chronic autoimmune disease, and current treatments for vitiligo have limited efficacy. Janus kinase (JAK) inhibitors could offer new therapeutic options. To evaluate the efficacy and safety of baricitinib, an oral JAK1/2 inhibitor, combined with narrow-band ultraviolet B (NB-UVB) in vitiligo treatment. This prospective, controlled, open-label study included adults with progressive non-segmental vitiligo (NSV). Patients were assigned to combination therapy with baricitinib 2 mg daily and NB-UVB three times a week or NB-UVB alone three times a week (control). The primary endpoint was the proportion of patients achieving 50% or greater improvement from baseline in the total Vitiligo Area Scoring Index (T-VASI50) at week 16. Of the 33 patients (mean age, 34.1 years; 27.3% women) who completed the study, 12 of 17 (70.6%) patients in the combination group and 2 of 16 (12.5%) in the control group had a T-VASI50 response at week 16 (relative risk [RR] = 5.6; 95% CI = 1.5-21.4; p = 0.001). Adverse events were minor, including erythema, mild blister after phototherapy and acne. Combination therapy with low-dose baricitinib and NB-UVB was effective and well tolerated in adults with progressive NSV.

Sensory Symptoms as an Early Manifestation of Active Vitiligo: A Case-Control Clinical and Molecular Study

Vitiligo pathogenesis is complex. There is some evidence in support of the neurohormonal pathways involved. Although considered a nonpruritic condition, some patients may experience itching, which can occur ahead of the appearance of the patches. We aimed to assess sensory symptoms in active and stable vitiligo patients and to measure 3 neuropeptide expressions in their lesional skin (neuropeptide Y [NPY], calcitonin gene-related peptide [CGRP], and nerve growth factors [NGF]) to correlate neuropeptide levels and sensory symptoms, with vitiligo activity. This case-control study included 85 patients, aged 18 years and older, analyzed into active or stable vitiligo groups. Patients were screened for itching or other abnormal neurological sensations such as paresthesia and numbness. The Vitiligo Disease Activity Score, Vitiligo Signs of Activity Score, and dermoscopic score were performed to assess disease activity. Three neuropeptides were quantified by enzyme-linked immunosorbent assay in skin biopsies from the edge of vitiligo lesions. A normal control group was also included. Results showed that 24.7% of patients had sensory symptoms: itching (18.8%), paresthesia (2.4%), and numbness (3.5%). The NGF, CGRP, and NPY levels were significantly higher in skin of normal controls compared to stable and active vitiligo patients. They were lowest in active vitiligo skin (p = 0.001, 0.016, and 0.01, respectively). NGF was the most relevant neuropeptide to vitiligo activity and sensory manifestations. In conclusion, almost one-third of the patients with active vitiligo reported sensory symptoms, predominantly itching, thus sensory manifestations may suggest a prodroma of activity and could be included in the screening tools for vitiligo activity. Trial Registration: www.clinicaltrials.gov (NCT05390164).

Network pharmacology, molecular docking and experimental study on the mechanism of Curcumin's anti-ferroptosis in melanocytes

Ferroptosis is a form of regulated nonapoptotic cell death associated with iron-dependent lipid peroxidation, closely associated with Vitiligo. Although the impact of Curcumin (Cur), a polyphenolic compound derived from the plant Curcuma longa Linn, on vitiligo has been established, the specific role and potential mechanistic pathways through which Cur modulates ferroptosis in vitiligo remain elusive. In this study, the critical targets and potential mechanisms of Cur in treating vitiligo were predicted by network pharmacology and molecule docking. Then, the effects of Cur on Erastin-induced ferroptosis were investigated in melanocytes induced by Erastin in vitro. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of Cur acting on Vitiligo found that these intersection genes are associated with the vitiligo oxidative stress pathway, including nuclear factor erythroid 2-related factor 2(Nrf2)/Heme Oxygenase 1(HO-1) signaling pathway. Further molecular docking shows that Cur has a good binding effect with Nrf2(the binding energy of Cur and Nrf2 protein is -6 kcal/mol). Through the CCK8 assay, showed that 10 μM Cur treatment 24 h after Erastin significantly improved cell viability In vitro. Then we found that Erastin induced cell death, ROS production, the mitochondrial membrane potential(MMP) decreased, Superoxide dismutase (SOD) and Glutathione (GSH) levels reduced, Malonaldehyde (MDA) and iron ion accumulation in melanocytes. In addition, the expression of glutathione peroxidase 4(GPX4) mRNA and protein was inhibited, while the expression of acyl-CoA synthetase long-chain family member 4(ACSL4), Transferrin Receptor Protein 1(TFR1) mRNA and protein was increased. However, the damage induced by Erastin was significantly relieved by Cur and Fer-1 treatment. Mechanistically, Cur treatment significantly promoted nuclear translocation of transcriptional factor Nrf2 and HO-1 expression. Interestingly, pretreatment with ML385, a selective Nrf2 inhibitor, counteracted anti-ferroptosis effects induced by Cur treatment. Taken together, these results demonstrate that Cur inhibits ferroptosis by regulating the Nrf2/HO-1 pathway to protect melanocytes.

Evaluation of neutrophil activation marker in patients with vitiligo

BACKGROUND

Vitiligo is an inflammatory, autoimmune disorder. Its pathogenesis is unclear. A neutrophil activation marker (calprotectin) is a protein complex present in many different types of cells and may be used as an indicator of inflammation.

AIMS

This study is to assess calprotectin levels in non-segmental vitiligo patients and compare them to the severity of the illness to identify potential associations.

METHODS

The present inquiry was conducted on thirty non-segmental vitiligo patients and thirty healthy volunteers matched in terms of age and gender. The Vitiligo Area Scoring Index was used to assess the vitiligo severity. Calprotectin levels were measured in serum samples obtained from all participants by Enzyme Linked Immunosorbent Assay.

RESULTS

Compared to controls, non-segmental vitiligo patients had considerably elevated serum calprotectin levels. Additionally, calprotectin levels were shown to have a significant positive association with disease severity (r = 0.833, P = 0.000).

CONCLUSIONS

Elevated levels of serum calprotectin in non-segmental vitiligo patients relative to healthy individuals with high sensitivity indicated that it may have a role in the vitiligo pathophysiology and can act as a marker for disease monitoring.

Comparison of various excimer laser (EL) combination therapies for vitiligo: a systematic review and network meta-analysis

AIM

This study aimed to compare the efficacy and safety of excimer laser (EL)-based combination regimens in improving repigmentation.

METHODS

A comprehensive search was conducted in PubMed, Web of Science, Cochrane Library, and Embase on July 1, 2023, to include randomized controlled trials of EL combination treatments for vitiligo that met the criteria. The primary outcome measure was a repigmentation rate ≥ 75%, and the secondary outcome measures were a repigmentation rate of ≤ 25% and adverse events.

RESULTS

Eleven studies involving 348 patients were included. Network Meta-Analysis showed that EL combined with antioxidants (SUCRA = 98.8%), EL combined with calcipotriol (SUCRA = 59.8%) and EL combined with tacalcitol (SUCRA = 59.6%) were the three optimal interventions achieving repigmentation rates ≥ 75%. EL alone (SUCRA = 77.6%), EL combined with tacalcitol (SUCRA = 61.7%) and EL combined with antioxidants (SUCRA = 57.2%) were the three interventions with the highest rates of treatment failure. Adverse events in all groups mainly included erythema, burning sensation and hyperpigmentation. Based on the results of the current study, EL combination therapies were safe with mild adverse events.

CONCLUSION

EL combined with antioxidants was the preferred regimen for vitiligo, whereas EL alone was the regimen with the highest rate of treatment failure in vitiligo.

Vitiligo is associated with an increased risk of cardiovascular diseases: a large-scale, propensity-matched, US-based retrospective study

BACKGROUND

Vitiligo is an autoimmune disease, characterized by specific destruction of melanocytes. While associations with numerous comorbid conditions, which potentially increase the risk of cardiovascular diseases have been described, data on the risk for cardiovascular disease is inconclusive. To address this relevant knowledge gap, this study aims to identify the risk of cardiovascular disease in vitiligo.

METHODS

The US Collaborative Network was accessed using the TriNetX platform, allowing retrospective data retrieval from electronic health records (EHRs) from 57 US based health care organizations (HCOs). Patients with vitiligo and controls were identified by their respective ICD10 codes. Risk of onset of several cardiovascular diseases was determined in patients within 15 years after diagnoses.

FINDINGS

A total of 94 diagnoses with a prevalence of ≥1% in both cohorts, which consisted of 96,581 individuals per group after propensity-score-matching, were identified. Of those, 54 displayed an increased risk in vitiligo. None of the cardiovascular diseases investigated were associated with a decreased risk in patients with vitiligo. Specifically, cerebral infarction occurred in 1.3% of patients with vitiligo, and 1.0% in controls. This difference translated into a hazard ratio (HR) of 1.21 (95% confidence interval [CI] 1.11-1.32, padj < 0.001). Venous thromboembolism was recorded in 1.34% of cases and 1.02% of controls without vitiligo, resulting in an increased HR of 1.27 (95% CI 1.171-1.38, padj < 0.001). Further, major adverse cardiovascular events (MACE) as a composite endpoint was evaluated. The risk for MACE was increased following a vitiligo diagnosis (HR 1.28, 95% CI 1.22-1.35, padj < 0.001), which persisted in both sensitivity analyses.

INTERPRETATION

Patients with vitiligo display an increased risk of onset of cardiovascular diseases as compared to healthy individuals. Thus, vitiligo might require more precise monitoring and systemic treatment.

FUNDING

This research was supported by the Schleswig-Holstein Excellence-Chair Program from the State of Schleswig Holstein, by the Excellence Cluster Precision Medicine in Chronic Inflammation (DFG, EXC 2167), and by DFG Individual Grant LU 877/25-1.

Biomedical applications of tyrosinases and tyrosinase inhibitors

Tyrosinase is involved in several human diseases, among which hypopigmentation and depigmentation conditions (vitiligo, idiopathic guttate hypomelanosis, pityriasis versicolor, pityriasis alba) and hyperpigmentations (melasma, lentigines, post-inflammatory and periorbital hyperpigmentation, cervical idiopathic poikiloderma and acanthosis nigricans). There are increasing evidences that tyrosinase plays a relevant role in the formation and progression of melanoma, a difficult to treat skin tumor. Hydroquinone, azelaic acid and tretinoin (all-trans-retinoic acid) are clinically used in the management of some hyperpigmentations, whereas many novel chemotypes acting as tyrosinase inhibitors with potential antimelanoma action are being investigated. Kojic acid, hydroquinone, its glycosylated derivative arbutin, or the resorcinol derivative rucinol are used in cosmesis in creams as skin whitening agents, whereas no antimelanoma tyrosinase inhibitor reached clinical trials so far, although thiamidol is a recently approved new tyrosinase inhibitor for the treatment of melasma. Kojic acid and vitamin C are used for avoiding vegetable/food oxidative browning due to the tyrosinase-catalyzed reactions, whereas bacterial enzymes show potential in biotechnological applications, for the production of mixed melanins, for protein cross-linking reactions, for producing phenol(s) biosensors, of for the production of L-DOPA, an anti-Parkinson's disease drug.

Identification of Hub Genes in Comorbidity of Psoriasis and Vitiligo Using Bioinformatics Analysis

Background

Psoriasis and vitiligo are two common autoimmune skin diseases with increased risk of comorbidities, but the common molecular mechanism about the occurrence of these two diseases is still unknown.

Objective

This study aimed to identify the combined genetic profiles and evaluate the potential mechanism underlying the occurrence of this complication.

Methods

The Gene Expression Omnibus (GEO) database was used to obtain the gene expression profiles of psoriasis (GSE30999) and vitiligo (GSE75819), and common differentially expressed genes (DEGs) were identified using GEO2R. DEGs were analyzed using functional enrichment analysis, protein-protein interaction (PPI) network and module construction, hub gene identification, and co-expression analysis. And hub genes were identified using Cytoscape software, and the gene expression of hub genes were validated in psoriasis (GSE13355) and vitiligo (GSE65127) datasets and immunohistochemistry at the clinical sample.

Results

A total of 164 common DEGs with the same trend (137 upregulated and 27 downregulated) were selected for subsequent analysis. Functional analysis emphasized the important roles of the cell cycle and mitotic cell division, cytoskeletal reorganization, and chromatin remodeling in the complications of these two diseases. Fourteen important hub genes were identified, including BUB1, CEP55, CDK1, TOP2A, CENPF, PBK, MELK, CCNB2, MAD2L1, NUSAP1, TTK, NEK2, CDKN3, and PTTG1. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) may be an important immune checkpoint in the pathogenesis of the comorbidities.

Conclusion

Our study identified hub genes and potential mechanisms underlying psoriasis and vitiligo complications. And we proposed a new spatio-temporal theory and the probable immune checkpoint for the pathogenesis of the comorbidity which may provide new ideas for the further research.

Ultrasound Patterns of Vitiligo at High Frequency and Ultra-High Frequency

OBJECTIVES

To detect ultrasonographic anatomical alterations in all the skin layers in patients with vitiligo.

METHODS

A prospective observational color Doppler ultrasound study was performed in nonsegmental face and/or neck vitiligo patients without a history of previous treatments. Two sites, a lesional area and a contralateral clinically healthy region, were ultrasonographically studied and compared in the same patient. All cases were studied in high-frequency (24 MHz) and ultra-high-frequency (70 MHz) ultrasound devices with the highest axial spatial resolution available in the market. Demographic data of the sample, ultrasound grayscale, and color Doppler features were recorded and analyzed.

RESULTS

Ten patients met the study criteria (60% females; mean age 49 years). All cases presented ultrasonographic undulation of the epidermis in the affected zones vs 50% in the healthy control regions, being more prominent in the vitiligo areas. Eighty percent demonstrated intense hypoechoic thin plaques in the upper dermis (subepidermal). All vitiligo areas presented thickening and hypoechogenicity of the regional hair follicles and/or pilosebaceous units. Ninety percent showed prominent sebaceous glands, and 20% demonstrated a hypoechoic cap surrounding the sebaceous glands in the lesional areas. Dermal hypervascularity was detected in 100% of the affected regions and 40% of the clinically healthy areas.

CONCLUSION

Ultrasound can identify subclinical inflammatory cutaneous patterns in the epidermis, dermis, hair follicles, pilosebaceous units, and sebaceous glands in vitiligo. This noninvasive information can support early detection, monitoring, and research, including the clinical trials of drugs used to manage this devastating disease.

Role of Cytokines and Chemokines in Vitiligo and Their Therapeutic Implications

Vitiligo is a persistent autoimmune disease characterized by progressive depigmentation of the skin caused by the selective destruction of melanocytes. Although its etiopathogenesis remains unclear, multiple factors are involved in the development of this disease, from genetic and metabolic factors to cellular oxidative stress, melanocyte adhesion defects, and innate and adaptive immunity. This review presents a comprehensive summary of the existing knowledge on the role of different cellular mechanisms, including cytokines and chemokines interactions, in the pathogenesis of vitiligo. Although there is no definitive cure for vitiligo, notable progress has been made, and several treatments have shown favorable results. A thorough understanding of the basis of the disease uncovers promising drug targets for future research, providing clinical researchers with valuable insights for developing improved treatment options.

The role of serum inflammatory factors in predicting treatment response in patients with vitiligo and concomitant Hashimoto's thyroiditis

Introduction

Vitiligo (VL) is associated with several autoimmune diseases, especially Hashimoto's thyroiditis, VL and concomitant Hashimoto's thyroiditis (HT) up to 34% in VL.

Aim

To assess the predictive value of serum inflammatory factors in guiding treatment response among patients with concurrent VL and concomitant HT.

Material and methods

This retrospective study enrolled 67 cases of VL and concomitant HT, and the patients according to treatment outcomes were divided into the unsatisfied group and the satisfied group. The serum thyroid parameters, autoimmune markers, and inflammatory factor levels were analysed and the correlation analysis of serum inflammatory factors was made.

Results

The study analysis of serum thyroid parameters showed elevated levels of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), thyroperoxidase (TPO), and thyroglobulin (Tg) (p < 0.05) in the group with unsatisfactory treatment response. Patients in the unsatisfied group exhibited elevated inflammatory factor levels of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10) (p < 0.05) compared to their counterparts in the satisfied group. Correlation analysis showed that the levels of the above inflammatory factors were significantly negatively correlated with the treatment response.

Conclusions

CRP, TNF-α, IL-6, IL-8, IL-10 showed the strongest correlation with VL and concomitant HT, and serum inflammatory factors levels can predict treatment response in patients with VL and concomitant HT.

A Mendelian randomization study on the causal effects of circulating cytokines on the risk of vitiligo

Background

Accumulating evidence reveals an association between circulating cytokine levels and vitiligo. However, the causal association between circulating cytokine levels and vitiligo remains unrevealed.

Methods

We performed a two-sample Mendelian randomization (MR) analysis using a genome-wide association study of the 41 cytokines dataset, which was conducted with 3 Finnish cohorts (n = 8,293). Vitiligo data were acquired from strictly defined vitiligo data collected by FinnGenbiobank analysis, which included 207,613 European ancestors (131 vitiligo patients, 207,482 controls). The inverse-variance weighted (IVW) method, weighted median (WME), simple model, weighted model, and MR-Egger were used to determine the changes in vitiligo pathogenic cytokine taxa, followed by sensitivity analysis, including horizontal pleiotropy analysis. The MR Steiger test evaluated the strength of a causal association, and the leave-one-out method was used to assess the reliability of the results. The possibility of reverse causality was also investigated using a reverse MR study.

Results

We observed that rising IL-4 levels generated an enhanced probability of vitiligo in IVW (OR 2.72, 95%CI 1.19-6.22, p = 0.018). According to the results of the MR analysis, there were causal links between IL-4 and vitiligo. Results were steady after sensitivity and heterogeneity analyses.

Conclusion

Our research reveals that a genetically determined increased level of circulating IL-4 may be linked to a higher risk of developing vitiligo. The development of innovative treatment approaches (such as tofacitinib or dupilumab) that focus on blocking IL-4 as a novel way of preventing and treating vitiligo is significantly impacted by our findings.

The role of aryl hydrocarbon receptor in vitiligo: a review

Vitiligo is an acquired autoimmune dermatosis characterized by patchy skin depigmentation, causing significant psychological distress to the patients. Genetic susceptibility, environmental triggers, oxidative stress, and autoimmunity contribute to melanocyte destruction in vitiligo. Due to the diversity and complexity of pathogenesis, the combination of inhibiting melanocyte destruction and stimulating melanogenesis gives the best results in treating vitiligo. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that can regulate the expression of various downstream genes and play roles in cell differentiation, immune response, and physiological homeostasis maintenance. Recent studies suggested that AhR signaling pathway was downregulated in vitiligo. Activation of AhR pathway helps to activate antioxidant pathways, inhibit abnormal immunity response, and upregulate the melanogenesis gene, thereby protecting melanocytes from oxidative stress damage, controlling disease progression, and promoting lesion repigmentation. Here, we review the relevant literature and summarize the possible roles of the AhR signaling pathway in vitiligo pathogenesis and treatment, to further understand the links between the AhR and vitiligo, and provide new potential therapeutic strategies.

A case of vitiligo that followed the path of a varicose vein in the lower leg

Vitiligo is an acquired chronic depigmenting disorder of the skin and is characterized by the destruction of melanocytes. One of the clinical features of vitiligo is that damage to normal skin frequently results in the formation of depigmented macules, which is known as Köebner's phenomenon (KP). Here, we presented a case of vitiligo, in which depigmented macules followed the course of a dilated varicose vein. Dilatation of blood vessels was considered to contribute to the development of the vitiliginous lesions as a trigger for KP. Any kind of skin injury can trigger KP, but this is only the second case in which a dilated blood vessel caused KP in vitiligo. J. Med. Invest. 71 : 177-178, February, 2024.

Antioxidant mechanisms of mesenchymal stem cells and their therapeutic potential in vitiligo

Vitiligo is a skin pigmentation disorder caused by melanocyte damage or abnormal function. Reac-tive oxygen species Reactive oxygen species can cause oxidative stress damage to melanocytes, which in turn induces vitiligo. Traditional treatments such as phototherapy, drugs, and other methods of treatment are long and result in frequent recurrences. Currently, mesenchymal stem cells (MSCs) are widely used in the research of various disease treatments due to their excellent paracrine effects, making them a promising immunoregulatory and tissue repair strategy. Furthermore, an increasing body of evi-dence suggests that utilizing the paracrine functions of MSCs can downregulate oxidative stress in the testes, liver, kidneys, and other affected organs in animal models of certain diseases. Addition-ally, MSCs can help create a microenvironment that promotes tissue repair and regeneration in are-as with oxidative stress damage, improving the disordered state of the injured site. In this article, we review the pathogenesis of oxidative stress in vitiligo and promising strategies for its treatment.

Novel Janus Kinase Inhibitors in the Treatment of Dermatologic Conditions

Janus kinase inhibitors, also known as JAK inhibitors, JAKinibs or JAKi, are a new group of disease-modifying drugs. They work by inhibiting enzymes involved in the transmission of information from receptors located in the cell membrane to the cell interior, specifically to the cell nucleus, thus disrupting the JAK-STAT pathway. This pathway plays a role in key cellular processes such as the immune response and cell growth. This feature is used in the treatment of patients with rheumatological, gastroenterological and hematological diseases. Recently, it has been discovered that JAK-STAT pathway inhibitors also show therapeutic potential against dermatological diseases such as atopic dermatitis, psoriasis, alopecia areata and acquired vitiligo. Studies are underway to use them in the treatment of several other dermatoses. Janus kinase inhibitors represent a promising class of drugs for the treatment of skin diseases refractory to conventional therapy. The purpose of this review is to summarize the latest knowledge on the use of JAKi in dermatological treatment.

Biology of Interleukin-17 and Novel Therapies for Hidradenitis Suppurativa

Skin disorders affect ∼40% of the human population. One of the most debilitating cutaneous disorders is Hidradenitis suppurativa (HS), a noncommunicable chronic inflammatory disease with an estimated global prevalence of 0.4% to 2.5%. In January 2011, high levels of IL-17 were discovered in skin lesions of HS patients. In the following years, translational and clinical research led to a better understanding of the pathogenesis of HS. In June 2023, more than 12 years after the initial note, secukinumab, an anti-IL-17A monoclonal antibody, was approved for the treatment of moderate to severe HS. This is the next milestone in improving the treatment of these patients after the approval of the anti-TNF-α monoclonal antibody adalimumab in 2015. In this review article, we present the IL-17 pathway in HS and discuss the use of secukinumab as a therapeutic option for this disease. Our review starts with a description of the epidemiology, clinical features, etiology, and pathogenesis of HS. An overview of the IL-17/IL-17 receptor system in general and a detailed description of the known facts about the expression and action of IL-17 in HS follow. Afterward, we consider the results of clinical trials evaluating the safety and efficacy of IL-17 inhibitors in HS. Finally, a comparison is made between secukinumab and adalimumab and the characteristics of the patients that may be particularly suitable for each of these biologics are described.

Syringetin Promotes Melanogenesis in B16F10 Cells

Syringetin, an active compound present in red grapes, jambolan fruits, Lysimachia congestiflora, and Vaccinium ashei, is a dimethyl myricetin derivative which contains free hydroxyl groups at the C-2' and C-4' positions in ring B. Recent studies have revealed that syringetin possesses multiple pharmacological properties, such as antitumor, hepatoprotective, antidiabetic, antioxidative, and cytoprotective activities. To date, there has been no attempt to test the action of syringetin on melanogenesis. In addition, the molecular mechanism for the melanogenic effects of syringetin remains largely unknown. In this study, we investigated the effect of syringetin on melanogenesis in a murine melanoma cell line from a C57BL/6J mouse, B16F10. Our results showed that syringetin markedly stimulated melanin production and tyrosinase activity in a concentration-dependent manner in B16F10 cells. We also found that syringetin increased MITF, tyrosinase, TRP-1, and TRP-2 protein expression. Moreover, syringetin inhibited ERK and PI3K/Akt phosphorylation by stimulating p38, JNK, PKA phosphorylation levels, subsequently stimulating MITF and TRP upregulation, resulting in the activation of melanin synthesis. Furthermore, we observed that syringetin activated phosphorylation of GSK3β and β-catenin and reduced the protein level of β-catenin, suggesting that syringetin stimulates melanogenesis through the GSK3β/β-catenin signal pathway. Finally, a primary skin irritation test was conducted on the upper backs of 31 healthy volunteers to determine the irritation or sensitization potential of syringetin for topical application. The results of the test indicated that syringetin did not cause any adverse effects on the skin. Taken together, our findings indicated that syringetin may be an effective pigmentation stimulator for use in cosmetics and in the medical treatment of hypopigmentation disorders.

Etiopathogenesis and Emerging Methods for Treatment of Vitiligo

Vitiligo is an acquired chronic depigmenting disorder of skin. It is mostly asymptomatic and characterized by amelanotic macules and patches that affects 0.5% to 2% of the world's population. The etiology of vitiligo has not been clearly elucidated and multiple theories have been proposed regarding the causes of the disorder. Among the most prevalent theories, the genetic predisposition, oxidative stress theory, promotion of cellular stress and pathologic influence of lymphocytes T have been highlighted. As a result of increases in in-depth knowledge concerning the pathogenetic processes in vitiligo, we review the most recent information concerning its etiopathogenesis and treatment methods including topical and oral Janus kinase inhibitors, prostaglandins and their analogues, namely afamelanotide, Wnt/β-catenin-signaling agonists and cell-based therapies. Topical ruxolitinib has been registered for vitiligo treatment, whereas other agents as oral ritlecitinib, afamelanotide and latanoprost have been studied in ongoing clinical trials. New highly effective therapeutic strategies may be developed thanks to molecular and genetic studies.