Physiopathology and genetics of vitiligo

A scoping review of the extent of the clinical research on the vitiligo extent score

Vitiligo is a chronic skin condition with no cure. Clinical assessment and treatment evaluation rely heavily on clinometry tools and expert knowledge. The Vitiligo Extent Score has been proposed as one of the most reliable and easy-to-use clinometry tools for vitiligo. We conducted a scoping review to identify all evidence on clinical research for the Vitiligo Extent Score. Databases searched included: MEDLINE (PubMed), Embase, Open Grey, Lens, and Directory of Open Access Journals (DOAJ). We followed the approach proposed in the Joanna Briggs Institute Reviewer's Manual and reported this review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. The results are presented in sections covering VES reliability, its smallest detectable change, minimally important change, modifications proposed to the instrument, an extension of cross-cultural validation, and comparison to other clinical scoring instruments. The systematic review identified 42 records, and 23 studies were included in the final report. The VES demonstrated good or excellent reliability across different clinical scenarios and when used by experts and non-experts. The VES has a low minimally important change that overlaps with the smallest detectable change. The instrument has been modified for various clinical scenarios, including perifollicular assessment, patient-oriented scoring, and target evaluation. To date, the VES has only been cross-culturally validated outside its developmental population for patients in Thailand. Finally, the VES has been used in clinical research to assess disease severity, its correlation with other variables, evaluate vitiligo response to therapy, and develop disease extent scores. The VES is highly reliable, easy to use, and versatile for clinical research and everyday clinical assessment. However, more cross-cultural validations are needed to extend its applicability.

Impact of Consanguinity and Familial Aggregation on Vitiligo Epidemiology in Saudi Arabia: A Case-Control Study

Background Vitiligo, characterized by depigmented patches due to melanocyte loss, involves genetic, autoimmune, and environmental factors. Recent studies suggest a link between family history, consanguinity, and vitiligo prevalence, particularly in regions with prevalent consanguineous marriages. This study explored the relationship between consanguinity and familial vitiligo prevalence in Saudi Arabia. Methods A case-control study enrolled 792 participants from Saudi dermatology clinics (382 vitiligo cases, 408 controls). Family histories and consanguinity levels were assessed. Logistic regression analysis, adjusting for relevant variables, evaluated associations. Results Significant associations were found between vitiligo and both parental consanguinity and family history. Cases had higher consanguinity rates, with 246 out of 382 (64.4%), compared to controls, with 161 out of 408 (39.5%). A positive family history of vitiligo was more common in cases, with 184 out of 382 (48.2%) than in controls, with 90 out of 408 (22.1%). Logistic regression identified parental consanguinity and positive family history as significant risk factors for vitiligo, with adjusted odds ratios (aOR) of 2.39 and 2.92, respectively. Their synergistic effect notably amplified the risk (aOR = 7.58), indicating a complex genetic and familial influence on vitiligo in Saudi Arabia. Conclusions Consanguinity showed a significant association with vitiligo prevalence, highlighting genetic factors' role. Further genetic research is needed to identify specific mutations in vitiligo among consanguineous populations. Genetic counseling and awareness programs are crucial in regions with high consanguinity rates to mitigate vitiligo and other genetic disorders' risks.

Choroidal vascularity index and choroidal thickness assessment in vitiligo

CLINICAL RELEVANCE

Vitiligo is a skin disease characterised by depigmentation and loss of melanocytes. Melanocyte loss may not be limited to the skin in vitiligo, and various abnormalities may occur in the choroid, which is dense in melanocytes.

BACKGROUND

To evaluate structural changes in the choroid by measuring choroidal thickness and vascularity index using optical coherence tomography in patients with vitiligo and comparing them to healthy subjects.

METHODS

This study included 168 participants: 84 with vitiligo (30 females, 54 males) and 84 controls (36 females, 48 males). Choroidal thickness and vascularity index were measured using the enhanced depth imaging mode in spectral-domain optical coherence tomography. The choroidal thickness was measured at the following five points; subfoveal (SF), 500 μm (NCT1) and 1000 μm (NCT2) nasal to the fovea; and 500 μm (TCT1) and 1000 μm (TCT2) temporal to the fovea. The choroidal vascularity index was calculated using the ImageJ software.

RESULTS

SF (p < 0.001), NCT1 (p < 0.001), NCT2 (p = 0.021), TCT1 (p = 0.001), and TCT2 (p < 0.006) choroidal thicknesses were significantly smaller in the vitiligo group than in the control group. Total choroidal (p < 0.001) and stromal (p < 0.001) areas were significantly smaller in the vitiligo group than in the control group. Choroidal vascularity indices were significantly higher in the vitiligo group than in the control group (p < 0.001). However, luminal areas did not differ significantly between groups (p = 0.935).

CONCLUSION

Patients with vitiligo should be regularly monitored for choroidal alterations and, if necessary, referred to an ophthalmologist.

Gluten Intolerance and Its Association With Skin Disorders: A Narrative Review

Gluten sensitivity is defined as a chronic intolerance to gluten ingestion in genetically predisposed individuals. The etiology is thought to be immune-mediated and has a variable dermatologic presentation. Celiac disease (CD) is one of the most common forms of gluten intolerance and encompasses a wide range of extra-intestinal pathology, including cutaneous, endocrine, nervous, and hematologic systems. Psoriasis, another long-term inflammatory skin condition, has been linked to significant symptomatic improvement with a gluten-free diet (GFD). Palmoplantar pustulosis (PP), a variant of psoriasis, and aphthous stomatitis, which causes recurrent oral ulcers, have also exhibited beneficial results after the dietary elimination of gluten. In addition to this, dermatitis herpetiformis (DH), another immune-mediated skin disorder, is genetically similar to CD and has, therefore, shown tremendous improvement with a GFD. Another highly prevalent long-term skin condition called atopic dermatitis (AD), however, has revealed inconsistent results with gluten elimination and would require further research in the future to yield concrete results. Hereditary angioedema (HA) has shown an association with gluten intolerance in some patients who had symptomatic benefits with a GFD. Similarly, vitiligo and linear IgA bullous dermatosis have also shown some clinical evidence of reversal with a GFD. On the contrary, rosacea enhances the risk of developing CD. This narrative review emphasizes the potential impact of gluten intolerance on different cutaneous conditions and the potential therapeutic effect of a GFD on various symptomatic manifestations. There is a need for additional clinical and observational trials to further expand on the underlying pathophysiology and provide conclusive and comprehensive recommendations for possible dietary interventions.

3D biofabrication of diseased human skin models in vitro

Human skin is an organ located in the outermost part of the body; thus, it frequently exhibits visible signs of physiological health. Ethical concerns and genetic differences in conventional animal studies have increased the need for alternative in vitro platforms that mimic the structural and functional hallmarks of natural skin. Despite significant advances in in vitro skin modeling over the past few decades, different reproducible biofabrication strategies are required to reproduce the pathological features of diseased human skin compared to those used for healthy-skin models. To explain human skin modeling with pathological hallmarks, we first summarize the structural and functional characteristics of healthy human skin. We then provide an extensive overview of how to recreate diseased human skin models in vitro, including models for wounded, diabetic, skin-cancer, atopic, and other pathological skin types. We conclude with an outlook on diseased-skin modeling and its technical perspective for the further development of skin engineering.

Investigating melanogenesis-related microRNAs as disease biomarkers in vitiligo

Vitiligo is considered a disabling disease that affects physical, social, psychological, and occupational aspects of an individual's quality of life. The search for non-invasive and reliable biomarkers for vitiligo's early diagnosis, prognosis, and treatment prediction is under intensive investigation. There is currently an emerging interest in employing miRNAs as biomarkers to predict vitiligo diagnosis and prognosis, inspired by the well-preserved nature of miRNAs in serum or plasma. In the current study, we assessed a panel of 20 melanogenesis pathway-related microRNAs (miRNAs) using quantitative real-time PCR technique in 85 non-segmental vitiligo (NSV) patients compared to 85 normal controls followed by function and pathway enrichment analysis for the miRNAs with significant results. Twelve out of the 20 circulating miRNAs showed significantly higher expression levels in vitiligo patients relative to controls where miR-423 show the highest expression level followed by miR-182, miR-106a, miR-23b, miR-9, miR-124, miR-130a, miR-203a, miR-181, miR-152, and miR-320a. While six miRNAs (miR-224, miR-148a, miR-137, and miR-7, miR-148b, miR-145, miR-374b, and miR-196b) didn’t show significant expression level. The analysis of the receiver operating curve indicated that miR-423, miR-106a, and miR-182 were outstanding biomarkers with the highest areas under the curve in vitiligo. This study is the first Egyptian study to investigate a panel of miRNAs expression profile in the plasma of patients with NSV. Our results suggest that specific circulating miRNAs signature might be implicated in vitiligo pathogenesis and could potentially be used as biomarkers in vitiligo.

The skin redoxome

Redoxome is the network of redox reactions and redox active species (ReAS) that affect the homeostasis of cells and tissues. Due to the intense and constant interaction with external agents, the human skin has a robust redox signalling framework with specific pathways and magnitudes. The establishment of the skin redoxome concept is key to expanding knowledge of skin disorders and establishing better strategies for their prevention and treatment. This review starts with its definition and progress to propose how the master redox regulators are maintained and activated in the different conditions experienced by the skin and how the lack of redox regulation is involved in the accumulation of several oxidation end products that are correlated with various skin disorders.

Influence of Narrow-Band Ultra Violet B Phototherapy on Homocysteine Status: A Prospective Study of Patients with Different Cutaneous Disorders

Background: Artificial ultraviolet (UV) radiation is a mainstay in the treatment of a variety of inflammatory skin disorders. Despite existence from a wealth of studies on the impact of narrow-band UVB (NBUVB) on serum levels of nutrients, clinical data on its effect on serum homocysteine (HC) level, which is thought to be a risk factor for cardiovascular disorders, dementia, and depression, are scarce. Objective: To assess serum HC status before and after treatment with at least 30 sessions of NBUVB exposure in patients with various cutaneous disorders. Methods: A prospective cohort study was conducted on 39 patients with psoriasis, vitiligo, atopic dermatitis, and mycosis fungoides who underwent at least 30 sessions of NBUVB phototherapy. Serum HC was measured and compared before and after phototherapy. This study was approved by relevant ethics committee. Results: Levels of HC decreased by 24.8% after 30 sessions of NBUVB phototherapy (10.53 ± 3.64 μmol/L vs. 7.92 ± 3.26 μmol/L, p-value <0.0001) and this decrease was more prominent in male participants and patients older than 40 years. Conclusions: Based to our findings, NBUVB phototherapy might be a modality of choice especially for older male patients not only as an effective treatment for cutaneous conditions, but also as a modality with potential protective effects against cardio-cerebro-vascular accidents.

Clinical Features, Immunopathogenesis, and Therapeutic Strategies in Vitiligo

Vitiligo is an autoimmune disease of the skin characterized by epidermal melanocyte loss resulting in white patches, with an approximate prevalence of 0.5-2% worldwide. Several precipitating factors by chemical exposure and skin injury present commonly in patients with vitiligo. Although the diagnosis appears to be straightforward for the distinct clinical phenotype and specific histological features, vitiligo provides many challenges including chronicity, treatment resistance, frequent relapse, associated profound psychosocial effect, and negative impact on quality of life. Multiple mechanisms are involved in melanocyte disappearance, including genetics, environmental factors, and immune-mediated inflammation. Compelling evidence supports the melanocyte intrinsic abnormalities with poor adaptation to stressors leading to instability and release of danger signals, which will activate dendritic cells, natural killer cells, and innate lymphoid cells to initiate innate immunity, ultimately resulting in T-cell mediated adaptive immune response and melanocyte destruction. Importantly, the cross- talk between keratinocytes, melanocytes, and immune cells, such as interferon (IFN)-γ signaling pathway, builds inflammatory loops that give rise to the disease deterioration. Improved understanding of the immune pathogenesis of vitiligo has led to the development of new therapeutic options including Janus kinase (JAK) inhibitors targeting IFN-γ signaling pathways, which can effectively reverse depigmentation. Furthermore, definition of treatment goals and integration of comorbid diseases into vitiligo management have revolutionized the way vitiligo is treated. In this review, we highlight recent developments in vitiligo clinical aspects and immune pathogenesis. Our key objective is to raise awareness of the complexity of this disease, the potential of prospective therapy strategies, and the need for early and comprehensive management.

Transcriptome and Differential Methylation Integration Analysis Identified Important Differential Methylation Annotation Genes and Functional Epigenetic Modules Related to Vitiligo

Vitiligo is an pigmentation disorder caused by a variety of pathogenic factors; its main pathophysiological conditions include oxidative stress, immune activation, and genetic background. Additionally, DNA methylation is often associated with the pathogenesis of vitiligo; however, the underlying mechanism remains unknown. In the present study, we used the Human Methylation 850K BeadChip platform to detect DNA methylation changes in the vitiligo melanocytes. We then integrated the results with the transcriptome data of vitiligo melanocytes and lesions to analyse the correlation between differentially methylated levels and differentially expressed genes. The results showed that there was a significant negative correlation between methylation levels and differentially expressed genes. Subsequently, we enriched GO and KEGG based on methylated differentially expressed genes (MDEGs) using R package ClusterProfiler, and the results were closely related to the pathogenesis of vitiligo. In addition, we also constructed a PPI network of MDEGs and excavated three important functional epigenetic modules, involving a total of 12 (BCL2L1, CDK1, ECT2, HELLS, HSP90AA1, KIF23, MC1R, MLANA, PBK, PTGS2, SOX10, and TYRP1) genes. These genes affect melanocyte melanogenesis, cellular oxidative stress and other important biological processes. Our comprehensive analysis results support the significant contribution of the status of DNA methylation modification to vitiligo, which will help us to better understand the molecular mechanism of vitiligo and explore new therapeutic strategies.

308nm excimer lamp monotherapy for lip vitiligo-a short case series

Vitiligo is a common depigmenting condition that carries a high psychosocial morbidity, especially when it occurs over exposed areas like lips. Many of the current topical and systemic therapies are less effective in lip vitiligo, and surgical modality remains the mainstay of treatment of lip vitiligo. The 308-nm excimer laser in combination with topical calcineurin inhibitors and calcipotriene is effective in the treatment of lip vitiligo. This case series provide further evidence to support effectiveness of 308-nm excimer lamp even as monotherapy in darker individuals with lip vitiligo.

Phimosis: A rare complication of immunotherapy with durvalumab

We present a case of a 69 year old man with phimosis associated with immunotherapy with durvalumab for metastatic non-small-cell lung cancer. The patient developed vitiligo like dermatosis after the induction dose of durvalumab, subsequent administration of the immunotherapy the patient developed a fibrous ring of the foreskin. Immune-mediated adverse reactions have been described after the use of durvalumab, but, to our knowledge, there are no reports of phimosis and vitiligo like reactions.

The physiology of melanin deposition in health and disease

Eumelanin is the major pigment responsible for human skin color. This black/brown pigment is localized in membrane-bound organelles (melanosomes) found in specialized cells (melanocytes) in the basal layer of the epidermis. This review highlights the steps involved in melanogenesis in the epidermis and the disorders in skin pigmentation that occur when specific steps critical for this process are defective. Melanosomes, which contain tyrosinase, a major enzyme involved in melanin synthesis, develop through a series of steps in the melanocyte. They are donated from the melanocyte dendrites to the surrounding keratinocytes in the epidermis. In the keratinocytes, the melanosomes are found singly or packaged into groups, and as the keratinocytes move upward in the epidermis, the melanosomes start to degrade. This sequence of events is critical for melanin pigmentation in the skin and can be influenced by genetic, hormonal, and environmental factors, which all play a role in levels of melanization of the epidermis. The effects these factors have on skin pigmentation can be due to different underlying mechanisms involved in the melanization process leading to either hypo- or hyperpigmentary disorders. These disorders highlight the importance of mechanistic studies on the specific steps involved in the melanization process.

Role of Fatty Acids Intake in Generalized Vitiligo

Background

Previous studies indicated the effect of fat on autoimmune diseases. The present study was aimed to investigate the association between fat intake and vitiligo.

Methods

This case-control study was conducted in the Skin and Leishmania Research Center, Isfahan University of Medical Sciences, Isfahan, Iran. Intakes of fatty acids were examined for their relation to risk of vitiligo among 100 cases and 110 controls. We included patients who suffered from generalized or localized vitiligo for <5 years that was approved by a dermatologist via the Vitiligo European Task Force criteria and the vitiligo area scoring index. Fat intake was assessed through individual interviews by a standardized food frequency questionnaire.

Results

Vitiligo group consumed more saturated fatty acid (SFA) and less eicosapentaenoic acid and docosahexaenoic acid than control group, while other fatty acids were not significantly different among two groups (P > 0.05). Crude analysis showed that total fat (odds ratio [OR] = 3.33, 95% confidence interval [CI]: 1.46-7.58) and SFA (OR = 2.22, 95% CI: 1.04-4.90) intakes were associated with an increased risk of vitiligo (for highest quartile vs. lowest quartile). Results demonstrated a decrease in the risk of vitiligo for those within the highest quartile of monounsaturated fatty acids intake (OR = 0.41, 95% CI: 0.18-0.92). However, this relationship disappeared after adjustment for confounders as energy, age, sex, and body mass index, except for total fat (OR = 2.84, 95% CI: 1.63-5.44). Crude and adjusted analyses for polyunsaturated fatty acids and cholesterol intake were not statistically significant.

Conclusions

Total-fat content of the diet had more impressive role than the specific subclasses of fats on the incidence risk of vitiligo. High-fat diet escalated the vitiligo risk. Regarding the role of fats on skin autoimmune diseases especially vitiligo, future studies are crucial.

Study of the relation between two common cyclooxygenase 2 gene polymorphisms with risk of developing and subtypes of vitiligo in Egyptian patients

Background/Purpose

Genetic factors play an important role in the pathogenesis of vitiligo. Cyclooxygenase 2 (COX2) gene induced by ultraviolet radiation controls the synthesis of prostaglandins, which are are found to be beneficial in treating vitiligo. COX2 gene polymorphism has been previously evaluated in Chinese population. We aimed to study the relation between two common COX2 gene polymorphisms with vitiligo and its subtypes amongEgyptian patients.

Patients and Methods

This study included 200 participants (100 vitiligo patients and 100 healthy controls). COX2-765G/C and -1195A/G gene polymorphism was studied by restriction fragment length polymorphism polymerase chain reaction analysis and the results were compared between the two groups and among different subtypes of vitiligo.

Results

Frequency of COX2-1195 AA, AG, GG genotypes showed no significant association among patients with vitiligo (P = 0.626, 0.321, 0.08, respectively); those with generalized vitiligo (P = 0.739, 0.291, 0.101, respectively) and those with segmental vitiligo (P = 0.410, 1.00, 0.676, respectively) compared to the control group. Regarding COX2-765G/C genotypes, GG genotype was more frequent among patients with vitiligo [84 (84%)] compared to controls [63 (63%)] (P = 0.001). GC genotype was significantly less frequent [15 (15%)] among patients compared to controls [32 (32%)] (P = 0.005). Generalized and segmental types of vitiligo also showed no significant difference in the frequency of COX2-765G/C genotypes compared with controls.

Limitations

Being a pilot study, a relatively small number of participants were included.

Conclusion

COX2-1195A/G gene polymorphism is not associated with the risk of developing vitiligo or with vitiligo subtypes. COX2-765 GG genotype is associated with vitiligo, especially of the generalized type.

An update on the cutaneous manifestations of coeliac disease and non-coeliac gluten sensitivity

INTRODUCTION

Coeliac disease is a gluten-induced immune-mediated enteropathy, characterised by the expression of specific genotypes and the production of autoantibodies. The inflammatory process specifically targets the intestinal mucosa, but gastrointestinal and extraintestinal signs and symptoms can also be present. Non-coeliac gluten sensitivity (NCGS) can be diagnosed in individuals who have intestinal and/or extraintestinal symptoms related to the ingestion of gluten, but do not have autoantibodies and do not suffer from lesions in the duodenal mucosa. Among the extraintestinal manifestations, cutaneous manifestations are the most common for both diseases.

PURPOSE

We conducted this review to illustrate the common and uncommon features underlying the association of coeliac disease and NCGS with cutaneous manifestations related to gluten ingestion. Areas covered: The roles of innate and adaptive immunity in the cutaneous appearance of gluten sensitivity will be discussed.

Vitiligo Surgery: Shuffling Melanocytes

Vitiligo is a disorder characterized by the development of depigmented macules and patches secondary to melanocyte destruction. Several treatment options are available, including medical, light-based, and surgical therapies, that are often used in combination to achieve maximal repigmentation. Vitiligo surgery is an effective yet underperformed treatment, mainly because of lack of awareness and availability. The purpose of this article is to review one method of vitiligo surgery, the melanocyte-keratinocyte transplantation procedure, and discuss its utility in treating vitiligo.

Macrophage migration inhibitory factor as an incriminating agent in vitiligo

BACKGROUND

Vitiligo is an autoimmune skin disorder in which the loss of melanocytes is mainly attributed to defective autoimmune mechanisms and, lately, there has been more emphasis on autoinflammatory mediators. Among these is the macrophage migration inhibitory factor, which is involved in many autoimmune skin diseases. However, little is known about the contribution of this factor to vitiligo vulgaris.

OBJECTIVE

To determine the hypothesized role of migration inhibitory factor in vitiligo via estimation of serum migration inhibitory factor levels and migration inhibitory factor mRNA concentrations in patients with vitiligo compared with healthy controls. We also aimed to assess whether there is a relationship between the values of serum migration inhibitory factor and/or migration inhibitory factor mRNA with disease duration, clinical type and severity in vitiligo patients.

METHODS

Evaluation of migration inhibitory factor serum level and migration inhibitory factor mRNA expression by ELISA and real-time PCR, respectively, were performed for 50 patients with different degrees of vitiligo severity and compared to 15 age- and gender-matched healthy volunteers as controls.

RESULTS

There was a highly significant increase in serum migration inhibitory factor and migration inhibitory factor mRNA levels in vitiligo cases when compared to controls (p<0.001). There was a significant positive correlation between both serum migration inhibitory factor and migration inhibitory factor mRNA concentrations in vitiligo patients, and each of them with duration and severity of vitiligo. In addition, patients with generalized vitiligo have significantly elevated serum migration inhibitory factor and mRNA levels than control subjects.

STUDY LIMITATIONS

Small number of investigated subjects.

CONCLUSIONS

Migration inhibitory factor may have an active role in the development of vitiligo, and it may also be a useful index of disease severity. Consequently, migration inhibitory factor may be a new treatment target for vitiligo patients.

Evaluation of serum immunoglobulins concentrations and distributions in vitiligo patients

Vitiligo is a dermatological disorder with an autoimmune mechanism characterized by production of a variety of autoantibodies. Different levels of immunoglobulins can indicate the presence and the stage of some autoimmune diseases. We aimed to investigate serum IgA, IgM and IgG subclass levels and melanocyte-reactive antibodies in 65 vitiligo patients by the immunonephelometric assay (35 healthy people as controls). Compared with normal controls, a significant increase in total IgG, IgG1 and IgG2 (p = .005, p = .003 and p = .043, respectively) was observed in progressive nonsegmental vitiligo patients. Also, we found a significant decrease in IgG3 (p = .000 and p = .023) in progressive nonsegmental vitiligo patients and segmental patients. Moreover, we found the serum levels of IgG4 subclass in stable nonsegmental patients were significantly higher than those in normal controls (p = .018). Compared with controls, the positive rates of melanocyte-reactive antibodies were higher in progressive nonsegmental patients and stable nonsegmental patients (p = .032 and p = .046, respectively). Furthermore, we found higher level of IgG4 and lower level of IgM in male than those in female. Higher IgG1 level was also observed in patients with a family history than in those without a family history. In addition, there was a significant inverse correlation between the concentrations of IgG4 and disease duration. Our evaluation about the level of immunoglobulins might provide a useful insight into the pathological process of vitiligo.

Diabetes mellitus and the skin

Several dermatoses are routinely associated with diabetes mellitus, especially in patients with chronic disease. This relationship can be easily proven in some skin disorders, but it is not so clear in others. Dermatoses such necrobiosis lipoidica, granuloma annulare, acanthosis nigricans and others are discussed in this text, with an emphasis on proven link with the diabetes or not, disease identification and treatment strategy used to control those dermatoses and diabetes.

Topical mycophenolate mofetil in the treatment of vitiligo: a pilot study

BACKGROUND

Vitiligo is a multifactorial disease that is characterized by circumscribed depigmented macules and patches. Autoimmune reactions may play an important role in the pathogenesis of the disease. Mycophenolate mofetil is a drug that inhibits DNA synthesis in lymphocytes and has been used in autoimmune diseases such as immunobullous skin diseases, lupus erythematosus, and autoimmune hepatitis.

OBJECTIVES

The objective of this study was to show the efficacy of topical mycophenolate mofetil in the treatment of vitiligo.

METHODS

Thirty patients with limited vitiligo were enrolled in this study. The patients applied a topical preparation of mycophenolate mofetil 15% twice daily for three months and at the end of every month, repigmentation was assessed using the Vitiligo Area Scoring Index (VASI).

RESULTS

At the end of the third month, 36.6 % (n=11) of the patients showed about 25% repigmentation of the lesions. No side effects were observed throughout the study.

CONCLUSION

This study showed that topical mycophenolate mofetil can be somewhat effective in the treatment of vitiligo; however, it seems to be inferior to potent topical steroids in inducing repigmentation.

Systematic understanding the mechanisms of vitiligo pathogenesis and its treatment by Qubaibabuqi formula

ETHNOPHARMACOLOGICAL RELEVANCE

Vitiligo is a depigmentation disorder, which results in substantial cosmetic disfigurement and poses a detriment to patients' physical as well as mental. Now the molecular pathogenesis of vitiligo still remains unclear, which leads to a daunting challenge for vitiligo therapy in modern medicine. Herbal medicines, characterized by multi-compound and multi-target, have long been shown effective in treating vitiligo, but their molecular mechanisms of action also remain ambiguous.

MATERIALS AND METHODS

Here we proposed a systems pharmacology approach using a clinically effective herb formula as a tool to detect the molecular pathogenesis of vitiligo. This study provided an integrative analysis of active chemicals, drug targets and interacting pathways of the Uygur medicine Qubaibabuqi formula for curing Vitiligo.

RESULTS

The results show that 56 active ingredients of Qubaibabuqi interacting with 83 therapeutic proteins were identified. And Qubaibabuqi probably participate in immunomodulation, neuromodulation and keratinocytes apoptosis inhibition in treatment of vitiligo by a synergistic/cooperative way.

CONCLUSIONS

The drug-target network-based analysis and pathway-based analysis can provide a new approach for understanding the pathogenesis of vitiligo and uncovering the molecular mechanisms of Qubaibabuqi, which will also facilitate the application of traditional Chinese herbs in modern medicine.

Elevated Levels of SOX10 in Serum from Vitiligo and Melanoma Patients, Analyzed by Proximity Ligation Assay

Background

The diagnosis of malignant melanoma currently relies on clinical inspection of the skin surface and on the histopathological status of the excised tumor. The serum marker S100B is used for prognostic estimates at later stages of the disease, but analyses are marred by false positives and inadequate sensitivity in predicting relapsing disorder.

Objectives

To investigate SOX10 as a potential biomarker for melanoma and vitiligo.

Methods

In this study we have applied proximity ligation assay (PLA) to detect the transcription factor SOX10 as a possible serum marker for melanoma. We studied a cohort of 110 melanoma patients. We further investigated a second cohort of 85 patients with vitiligo, which is a disease that also affects melanocytes.

Results

The specificity of the SOX10 assay in serum was high, with only 1% of healthy blood donors being positive. In contrast, elevated serum SOX10 was found with high frequency among vitiligo and melanoma patients. In patients with metastases, lack of SOX10 detection was associated with treatment benefit. In two responding patients, a change from SOX10 positivity to undetectable levels was seen before the response was evident clinically.

Conclusions

We show for the first time that SOX10 represents a promising new serum melanoma marker for detection of early stage disease, complementing the established S100B marker. Our findings imply that SOX10 can be used to monitor responses to treatment and to assess if the treatment is of benefit at stages earlier than what is possible radiologically.

The design, synthesis and biological evaluation of pro-EGCG derivatives as novel anti-vitiligo agents

A series of prodrugs of EGCG derivatives were designed, synthesized, and the protective effect on melanocytes against H₂O₂-induced cell damage were extensively evaluated, demonstrating the potential application value of them in anti-vitiligo treatment.

The association between tumor necrosis factor-α-308 G/A polymorphism and risk for vitiligo: a meta-analysis

BACKGROUND

The contribution of tumor necrosis factor-α (TNF-α)-308 G/A gene polymorphism (rs1800629) to risk for vitiligo is subject to controversy.

OBJECTIVES

The fundamental purpose of the present meta-analysis was to investigate large-scale evidence to determine the overall association between TNF-α-308 G/A polymorphism and susceptibility to vitiligo.

METHODS

A literature search of the PubMed, EMBASE, Web of Science, and China National Knowledge Infrastructure (CNKI) databases was conducted to identify all studies referring to an association between TNF-α-308 G/A polymorphism and vitiligo published to June 1, 2014. The principal outcome measure for evaluating the strength of the association was the crude odds ratio (OR) along with the corresponding 95% confidence interval (CI). Data were extracted, and statistical analyses were implemented using stata Version 12.0.

RESULTS

Data for a total of 1505 vitiligo cases and 2253 controls from five case-control studies concentrating on the association between TNF-α-308 G/A polymorphism and vitiligo were included in this meta-analysis. Combined analysis revealed there to be no association between this polymorphism and susceptibility to vitiligo in five genetic models under random-effects models. A subgroup analysis by clinical type also demonstrated the absence of any association between TNF-α-308 G/A polymorphism and generalized vitiligo. However, a significant association was detected in the miscellaneous subgroup under the dominant model (fixed-effects model: OR 5.69, 95% CI 4.70-6.88; P = 0.000) and overdominant model (random-effects model: OR 5.24, 95% CI 2.26-12.17; P = 0.000).

CONCLUSIONS

This meta-analysis indicates that TNF-α-308 G/A polymorphism is not a genetic risk factor for vitiligo.

Inhibition of melanogenesis by β-caryophyllene from lime mint essential oil in mouse B16 melanoma cells

OBJECTIVE

Volatile essential oils of mint species are used for cosmetics and in skin care products. In this study, we evaluated the main chemical components of the lime mint and the anti-melanogenic properties of its main components.

METHODS

The essential oil was analysed by gas chromatography-mass spectrometry (GC/MS). The anti-melanogenic effects of mint essential oil and β-caryophyllene were investigated in B16F10 murine melanoma cells.

RESULTS

The main components of lime mint essential oil were found to be D-limonene (41.10%), D-carvone (8.58%), δ-selinene (6.73%) and β-caryophyllene (6.24%). The lime mint essential oil reduced melanin production in a dose-dependent manner in murine B16F10 cells. β-Caryophyllene, one of the main compounds in lime mint essential oil, could reduce melanogenesis by down-regulating the expression of MITF, TRP-1, TRP-2 and tyrosinase, resulting in a decrease in melanin content decrease.

CONCLUSION

These results reveal that lime mint essential oil and β-caryophyllene are considered to be valuable as potential skin-whitening agents.

Vitiligo: symptoms, pathogenesis and treatment

Vitiligo is an acquired cutaneous disorder of pigmentation, with an incidence of 0.5&#x0025; to 2&#x0025; worldwide. There are three major hypotheses for the pathogenesis of vitiligo that are not exclusive of each other: biochemical/cytotoxic, neural and autoimmune. Recent data provide strong evidence supporting an autoimmune pathogenesis of vitiligo. As vitiligo can have a major effect on quality of life, treatment can be considered and should preferably begin early when then disease is active. Current treatment modalities are directed towards stopping progression of the disease and achieving repigmentation. Therapies include corticosteroids, topical immunomodulators, photo(chemo)therapy, surgery, combination therapies and depigmentation of normally pigmented skin. It seems that traditional Chinese medicine could be more effective than the current treatment for vitligo.

Current aspects of vitiligo genetics

Vitiligo is a common acquired depigmentation disorder of the skin manifested by the presence of white macules. The disease occurs at a frequency of approximately 1–4% of the world population. Currently, the most popular theory of vitiligo development is a multifactorial hypothesis according to which genetic conditions predispose vitiligo macules to occur as a result of specific environmental factors. According to the genetic hypothesis, vitiligo inheritance is multigenic. Genetic studies conducted so far concern patients with non-segmental vitiligo. There are three basic techniques of genetic studies: candidate gene association studies, genomewide linkage studies and genome-wide association studies (GWAS). The GWAS are the “gold standard” for detecting susceptibility genes. Up to now, approximately 36 convincing non-segmental vitiligo susceptibility loci have been identified. Approximately 90% of them encode immunoregulatory proteins, while approximately 10% encode melanocyte proteins. The existence of various associations between vitiligo and other autoimmune diseases may provide new knowledge on the causes of many disorders. Examples include the inverse relationship between vitiligo and melanoma and association of vitiligo with other autoimmune diseases. The main goal of all researches is to find new, optimal therapeutic strategies for vitiligo and other autoimmune diseases.

Analysis of oxidative stress status, catalase and catechol-O-methyltransferase polymorphisms in Egyptian vitiligo patients

Vitiligo is the most common depigmentation disorder of the skin. Oxidative stress is implicated as one of the probable events involved in vitiligo pathogenesis possibly contributing to melanocyte destruction. Evidence indicates that certain genes including those involved in oxidative stress and melanin synthesis are crucial for development of vitiligo. This study evaluates the oxidative stress status, the role of catalase (CAT) and catechol-O-Methyltransferase (COMT) gene polymorphisms in the etiology of generalized vitiligo in Egyptians. Total antioxidant capacity (TAC) and malondialdehyde (MDA) levels as well as CAT exon 9 T/C and COMT 158 G/A polymorphisms were determined in 89 patients and 90 age and sex-matched controls. Our results showed significantly lower TAC along with higher MDA levels in vitiligo patients compared with controls. Meanwhile, genotype and allele distributions of CAT and COMT polymorphisms in cases were not significantly different from those of controls. Moreover, we found no association between both polymorphisms and vitiligo susceptibility. In conclusion, the enhanced oxidative stress with the lack of association between CAT and COMT polymorphisms and susceptibility to vitiligo in our patients suggest that mutations in other genes related to the oxidative pathway might contribute to the etiology of generalized vitiligo in Egyptian population.

Association of the 389 C/T polymorphism of the catalase gene with susceptibility to vitiligo: a meta-analysis

BACKGROUND

The 389 C/T polymorphism in the catalase gene, CAT, has been reported to be associated with the risk of vitiligo.

AIM

To evaluate the association of the CAT 389 C/T polymorphism with susceptibility to vitiligo.

METHODS

We undertook a literature search and included the relevant studies passing the selection criteria. After the relevant data were extracted from each study, we statistically analysed the strength of association between the CAT gene and vitiligo risk.

RESULTS

In total, 7 relevant studies were identified, comprising 1531 patients with vitiligo and 1608 controls. The genotype distribution in the controls of all studies complied with Hardy-Weinberg equilibrium. After pooling all studies, the results indicated that the 389 C/T polymorphisms in CAT were not associated with the risk of vitiligo in Asians and Turks; however the CT genotype might be a genetic risk factor for susceptibility to vitiligo (OR = 1.77, 95% CI 1.30-2.43, P < 0.001) and the CC genotype might decrease the risk of vitiligo (OR = 0.63, 95% CI 0.47-0.86, P < 0.01) in western Europeans.

CONCLUSIONS

The 389 C/T polymorphisms in the CAT gene may be associated with vitiligo in western Europeans. Further studies with larger sample sizes are warranted to confirm our findings.

Topical retinoids in skin ageing: a focused update with reference to sun-induced epidermal vitamin A deficiency

Vitamin A is an important constituent of the epidermis, where it plays a crucial role in epidermal turnover. A deficiency of epidermal vitamin A may be the consequence of nutritional vitamin A deficiency, exposure to sunlight or any UV source, oxidative stress or chronological ageing. As a consequence, any treatment aiming at increasing epidermal vitamin A would exert a protective effect against these deleterious conditions. Retinoids may counteract some deleterious actions of UV radiation by physical and biological mechanisms. Topical natural retinoic acid precursors such as retinaldehyde or retinol are less irritant than acidic retinoids and may prevent epidermal vitamin A deficiency due to nutritional deficiency, exposure to sunlight or any condition leading to free radical production. Retinoids may be combined with other compounds with complementary actions against ageing, nutritional deficiency and cancer, such as antioxidants, to potentiate their beneficial effects in the skin.

Role of oxidative stress in the pathogenesis of vitiligo with special emphasis on the antioxidant action of narrowband ultraviolet B phototherapy

Objectives

To evaluate the role of oxidative stress in the pathogenesis of vitiligo and the effect of narrowband (NB) ultraviolet (UV) B phototherapy on oxidative stress markers.

Methods

Patients with vitiligo and healthy control subjects were included in the study. Patients in the vitiligo group were treated with an NB-UVB regimen (3 × weekly for 6 months). Erythrocyte superoxide dismutase activity (SOD), erythrocyte malonyldialdehyde (MDA) and erythrocyte glutathione peroxidase activity (GSH-Px) levels were assessed in all participants at baseline, and after NB-UVB phototherapy in patients with vitiligo.

Results

A total of 24 patients with vitiligo and 27 control subjects were included in the study. Before treatment, erythrocyte MDA levels were significantly higher, and SOD and GSH-Px levels were significantly lower, in patients with vitiligo compared with controls. NB-UVB phototherapy was associated with a significant reduction in MDA levels and a significant increase in GSH-Px levels, compared with baseline, in patients with vitiligo.

Conclusion

NB-UVB phototherapy may relieve oxidative stress in patients with vitiligo by reversing the oxidant–antioxidant imbalance that is considered to play a role in the pathogenesis of this disease.

Whole Transcriptome Analysis (RNA Sequencing) of Peripheral Blood Mononuclear Cells of Vitiligo Patients

Vitiligo is an idiopathic disorder characterized by depigmented patches on the skin due to a loss of melanocytes. The cause of melanocyte destruction is not fully understood. The aim of this study was to detect the potential pathways involved in the vitiligo pathogenesis to further understand the causes and entity of vitiligo. For that the transcriptome of peripheral blood mononuclear cells of 4 vitiligo patients and 4 control subjects was analyzed using the SOLiD System platform and whole transcriptome RNA sequencing application. Altogether 2,470 genes were expressed differently and GRID2IP showed the highest deviation in patients compared to controls. Using functional analysis, altogether 993 associations between the gene groups and diseases were found. The analysis revealed associations between vitiligo and diseases such as lichen planus, limb-girdle muscular dystrophy type 2B, and facioscapulohumeral muscular dystrophy. Additionally, the gene groups with an altered expression pattern are participating in processes such as cell death, survival and signaling, inflammation, and oxidative stress. In conclusion, vitiligo is rather a systemic than a local skin disease; the findings from an enormous amount of RNA sequencing data support the previous findings about vitiligo and should be further analyzed.

Concise review of recent studies in vitiligo

Vitiligo is an acquired pigmentry disorder of the skin and mucous membranes which manifests as white macules and patches due to selective loss of melanocytes. Etiological hypotheses of vitiligo include genetic, immunological, neurohormonal, cytotoxic, biochemical, oxidative stress and newer theories of melanocytorrhagy and decreased melanocytes survival. There are several types of vitiligo which are usually diagnosed clinically and by using a Wood's lamp; also vitiligo may be associated with autoimmune diseases, audiological and ophthalmological findings or it can be a part of polyendocrinopathy syndromes. Several interventions are available for the treatment for vitiligo to stop disease progression and/or to attain repigmentation or even depigmentation. In this article, we will present an overall view of current standing of vitiligo research work especially in the etiological factors most notably the genetic components, also, types and associations and various and newer treatment modalities.

The association of FOXO3A gene polymorphisms with serum FOXO3A levels and oxidative stress markers in vitiligo patients

Vitiligo is an acquired epidermal pigment loss of the skin. Oxidative stress is one of the major theories in the pathophysiology of vitiligo. FOXO3A is the forkhead members of the class O (FOXO) transcription factors, and plays an important role in cell cycle regulation, apoptosis, oxidative stress, and DNA repair. The aim of our study was to investigate FOXO3A gene polymorphisms and FOXO3A protein levels, activities of superoxide dismutase (SOD) and catalase antioxidant enzymes in vitiligo patients and healthy controls. Moreover, the level of plasma advanced oxidation protein products (AOPP) in subjects was evaluated to understand the possible role of protein oxidation in disease etiology. Study groups included 82 vitiligo patients and 81 unrelated healthy controls. FOXO3A polymorphisms were determined using polymerase chain reaction-restriction fragment length polymorphism method. FOXO3A levels and catalase activity were measured by ELISA whereas AOPP levels and SOD activity was measured by spectrophotometric analysis. We found a significant relationship between rs4946936 polymorphism of FOXO3A gene and vitiligo/active vitiligo patients (p=0.017; p=0.019 respectively), but not for rs2253310 (p>0.05). SOD activity and AOPP levels of vitiligo patient were increased compared with control group, whereas FOXO3A levels and catalase enzyme activity of vitiligo patient were decreased compared with control group (p<0.05). Our study indicates that rs4946936 of FOXO3A gene may associate susceptibility of vitiligo, especially active vitiligo. Moreover, our results confirm that oxidative stress may play a role in the pathophysiology of vitiligo. Further studies with larger samples are required to elucidate the role of FOXO3A in vitiligo.

The role of tumor necrosis factor-α in the pathogenesis of vitiligo

Vitiligo is an acquired immune disorder of the skin characterized by the presence of white depigmented macules. Its immunopathogenesis is not completely understood, but inflammatory alterations in the skin microenvironment, and particularly increased expression of the cytokine tumor necrosis factor-α (TNFα), are thought to be essential regulators of melanocyte dysfunction and death. In this article we review the evidence that implicates TNFα in the pathogenesis of vitiligo, including studies on serum and tissue levels of TNFα, TNFα gene polymorphisms, in vitro studies, and therapeutic trials using TNFα inhibitors. TNFα emerges as a complex mediator with apparently conflicting roles in vitiligo.

Comparison of the 308-nm excimer laser with the 308-nm excimer lamp in the treatment of vitiligo--a randomized bilateral comparison study

BACKGROUND

Vitiligo is an acquired pigment disorder characterized by areas of depigmented skin resulting from the loss of epidermal melanocytes. Recently, several investigations have documented the benefits of excimer phototherapy (e.g., using the 308-nm excimer laser or the 308-nm excimer lamp) for the treatment of vitiligo.

AIM

To compare the effectiveness of the 308-nm excimer laser with the 308-nm excimer lamp in the treatment of vitiligo patients.

METHODS

This intervention study was designed as a randomized self-control trial. Fourteen subjects with 48 symmetrical vitiligo lesions were enrolled in this study. One lesion was treated with the 308-nm excimer laser, and its counterpart was treated with the 308-nm excimer lamp. Lesions were treated three times a week with the same dose on both sides for a total of 20 sessions.

RESULTS

All of the patients completed the study, and 48 lesions were treated. The two treatments exhibited similar results in terms of repigmentation.

CONCLUSIONS

The 308-nm excimer lamp and the 308-nm excimer laser exhibited similar efficacies in treating vitiligo.

WITHDRAWN: Comparision between 308-nm excimer laser and 308-nm excimer lamp in the treatment of vitiligo - a randomized self control study

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