Positive pleiotropic effects of HMG-CoA reductase inhibitor on vitiligo

Metabolic anomalies in vitiligo: a new frontier for drug repurposing strategies

Vitiligo is a chronic autoimmune condition characterized by the destruction of melanocytes, leading to patchy loss of skin depigmentation. Although its precise cause remains unclear, recent evidence suggests that metabolic disturbances, particularly oxidative stress and mitochondrial dysfunction, may play a significant role in the pathogenesis of the disease. Oxidative stress is thought to damage melanocytes and trigger inflammatory responses, culminating in melanocyte immune-mediate destruction. Additionally, patients with vitiligo often exhibit extra-cutaneous metabolic abnormalities such as abnormal glucose metabolism, dyslipidemia, high fasting plasma glucose levels, high blood pressure, out of range C-peptide and low biological antioxidant capacity, suggesting a potential link between metabolic impairment and vitiligo development. This implies that the loss of functional melanocytes mirrors a more general systemic targetable dysfunction. Notably, therapies targeting metabolic pathways, particularly those involving mitochondrial metabolism, such as the peroxisome proliferator-activated nuclear receptor γ (PPARγ) agonists, are currently being investigated as potential treatments for vitiligo. PPARγ activation restores mitochondrial membrane potential, mitochondrial DNA copy number and, consequently, ATP production. Moreover, PPARγ agonists counteract oxidative stress, reduce inflammation, inhibit apoptosis, and maintain fatty acid metabolism, in addition to the well-known capability to enhance insulin sensitivity. Additionally, increasing evidence of a strong relationship between metabolic alterations and vitiligo pathogenesis suggests a role for other approved anti-diabetic treatments, like metformin and fibrates, in vitiligo treatment. Taken together, these data support the use of approaches alternative to traditional immune-suppressive treatments for the treatment of vitiligo.

PCSK9 Inhibitors and the Risk of Vitiligo: A Mendelian Randomization Study

Lipid-lowering agents have been suggested as a therapeutic option for vitiligo on the basis of the potential pathogenic role of lipid metabolism abnormalities. We aimed to explore the impact of genetically proxied lipid-lowering agents on the risk of vitiligo and potentially associated mediators. GWAS summary statistics for European ancestry were extracted from the largest available meta-analysis for vitiligo: the Global Lipids Genetics Consortium for 7 lipid profiles and 2 large biobanks, UK Biobank and deCODE, for 4719 proteins. After identifying lipid-lowering agents with genetically proxied protective effects against vitiligo using lipid-lowering and protein-inhibition Mendelian randomization (MR) analyses, multivariable and 2-step MR analyses were conducted to identify potential mediators between lipid-lowering agents and vitiligo. Lipid-lowering MR indicated a potential role of PCSK9 in reducing the vitiligo risk (OR [95% confidence interval] = 0.71 [0.52-0.95]), which was replicated in PCSK9-inhibition MR analyses across 2 separate biobanks (UK Biobank: OR [95% confidence interval] = 0.82 [0.71-0.96]; deCODE: OR [95% confidence interval] = 0.78 [0.67-0.91]). Multivariable MR suggested that well-known lipid profiles do not mediate the relationship between PCSK9 and vitiligo, whereas 2-step MR analyses identified 5 potential protein mediators (CCN5, CXCL12, FCRL1, legumain, and FGF2). Hence, PCSK9 inhibitor may attenuate the vitiligo risk; PCSK9 and the potential protein mediators can serve as promising novel therapeutic targets for its effective treatment.

Emerging Therapeutic Innovations for Vitiligo Treatment

Vitiligo is a chronic autoimmune disorder with a multifactorial etiology, typically manifesting as localized or generalized hypopigmentation or depigmentation of the skin and mucous membranes. The pathogenesis of vitiligo is complex and significantly impacts patients' quality of life. Although traditional treatments such as hormone therapy, topical medications, and laser therapy can help control the disease to some extent, their outcomes remain unsatisfactory. Therefore, ongoing research is crucial to explore and develop novel treatment strategies while assessing their efficacy and safety. This review aims to classify and summarize various new candidate drugs for vitiligo currently undergoing clinical trials, providing a reference for clinical practice. Recent advancements in the understanding of the pathogenesis of vitiligo have facilitated the development of potential treatment strategies, such as Janus kinase inhibitors, cytokine blockers, and agents targeting tissue-resident memory or regulatory T cells. These emerging therapies offer hope to patients with vitiligo, though further investigation is needed to confirm their safety, efficacy, and optimal treatment regimens.

Identifying the Genetic Associations Between Diabetes Mellitus and the Risk of Vitiligo

Purpose

While increasing observational studies have suggested an association between diabetes mellitus (DM) and vitiligo, the causal relationship and possible mechanism remain unclear.

Methods

Publicly accessible genome-wide association study (GWAS) was utilized to conduct a bidirectional two-sample Mendelian randomization (MR) analysis. GWAS data for diabetes and vitiligo were obtained from the UK Biobank Consortium (20203 cases and 388756 controls) and the current GWAS data with largest cases (GCST004785, 4680 cases and 39586 controls) for preliminary analysis, respectively. Inverse variance weighting (IVW) was used as the main analysis method. Several sensitivity analyses were utilized to test the pleiotropy or heterogeneity. To explore the possible mechanism of gene-generating effects represented by the final instrumental variables in the analysis, enrichment analysis was conducted using the DAVID and STRING database.

Results

IVW method showed a significant genetic causal association between DM and vitiligo (OR = 1.20, 95% CI: 1.08-1.33, PIVW = 0.0009). Diabetes subtype analysis showed that T2D (type 2 diabetes) were associated with an increased risk of vitiligo (OR = 1.13, 95% CI: 1.00-1.27, PIVW = 0.0432). Sensitivity analysis further confirmed the robustness of the results. The enrichment analysis revealed that the genetic inducing effects of diabetes mellitus on vitiligo were primarily about pancreatic secretion and protein digestion and absorption pathway.

Conclusion

Our findings provide genetic evidence that there is a notable association between T2D and an elevated risk of vitiligo in European populations. This result may explain why the co-presentation of T2D and vitiligo is often seen in observational studies, and emphasize the significance of vigilant monitoring and clinical evaluations for vitiligo in individuals diagnosed with T2D. The aberrant glucose and lipid metabolism and the primary nutrient absorption disorder of vitiligo brought on by diabetes may be the potential mechanisms behind this association.

Involvement of interferon γ-producing mast cells in immune responses against melanocytes in vitiligo requires MrgX2 activation

BACKGROUND

Increasing evidence indicates that oxidative stress and interferon γ (IFNγ)-driven cellular immune responses are responsible for the pathogenesis of vitiligo. However, the connection between oxidative stress and the local production of IFNγ in early vitiligo remains unexplored. The aim of this study was to identify the mechanism underlying the production of IFNγ by mast cells and its impact on vitiligo pathogenesis.

METHODS

Skin specimens from the central, marginal, and perilesional skin areas of active vitiligo lesions were collected to characterize changes of mast cells, CD8+ T cells, and IFNγ-producing cells. Cell supernatants from hydrogen peroxide (H2O2)-treated keratinocytes (KCs) were harvested to measure levels of soluble stem cell factor (sSCF) and matrix metalloproteinase (MMP)-9. A murine vitiligo model was established using Mas-related G protein-coupled receptor-B2 (MrgB2, mouse ortholog of human MrgX2) conditional knockout (MrgB2-/-) mice to investigate IFNγ production and inflammatory cell infiltrations in tail skin following the challenge with tyrosinase-related protein (Tyrp)-2 180 peptide. Potential interactions between the Tyrp-2 180 peptide and MrgX2 were predicted using molecular docking. The siRNAs targeting MrgX2 and the calcineurin inhibitor FK506 were also used to examine the signaling pathways involved in mast cell activation.

RESULTS

IFNγ-producing mast cells were closely aligned with the recruitment of CD8+ T cells in the early phase of vitiligo skin. sSCF released by KCs through stress-enhanced MMP9-dependent proteolytic cleavage recruited mast cells into sites of inflamed skin (Perilesion vs. lesion, 13.00 ± 4.00/HPF vs. 26.60 ± 5.72/HPF, P <0.05). Moreover, IFNγ-producing mast cells were also observed in mouse tail skin following challenge with Tyrp-2 180 (0 h vs. 48 h post-recall, 0.00 ± 0.00/HPF vs. 3.80 ± 1.92/HPF, P <0.05). The IFNγ+ mast cell and CD8+ T cell counts were lower in the skin of MrgB2-/-mice than in those of wild-type mice (WT vs. KO 48 h post-recall, 4.20 ± 0.84/HPF vs. 0.80 ± 0.84/HPF, P <0.05).

CONCLUSION

Mast cells activated by MrgX2 serve as a local IFNγ producer that bridges between innate and adaptive immune responses against MCs in early vitiligo. Targeting MrgX2-mediated mast cell activation may represent a new strategy for treating vitiligo.

Topical application of simvastatin acid sodium salt and atorvastatin calcium salt in vitiligo patients. Results of the randomized, double-blind EVRAAS pilot study

Contemporary treatment of vitiligo remains a great challenge to practitioners. The vast majority of currently conducted clinical trials of modern therapeutic methods are focused on systemic medications, while there is only a very limited number of reports on new topical treatment in vitiligo. With their pleiotropic activities statins turned out to be efficient in the treatment of various autoimmune/autoinflammatory disorders. The randomized, double-blind placebo-controlled study of topical administration of the active forms of simvastatin and atorvastatin has been designed to evaluate their efficacy in patients with vitiligo. The study was registered in clinicaltrials.gov (registration number NCT03247400, date of registration: 11th August 2017). A total of 24 patients with the active form of non-segmental vitiligo were enrolled in the study. The change of absolute area of skin lesions, body surface area and vitiligo area scoring index were evaluated throughout the 12 week application of ointments containing simvastatin and atorvastatin. Measurements were performed with planimetry and processed using digital software. Use of active forms of simvastatin and atorvastatin did not result in a significant repigmentation of the skin lesions throughout the study period. Within the limbs treated with topical simvastatin, inhibition of disease progression was significantly more frequent than in the case of placebo (p = 0.004), while the difference was not statistically significant for atorvastatin (p = 0.082). Further studies of topical simvastatin in vitiligo patients should be considered.

Assessing effectiveness of adding niosomal atorvastatin 1% ointment to topical calcineurin inhibitor treatment in non-segmental vitiligo

BACKGROUND

Treatment of vitiligo is still a big challenge for dermatologists. The efficacy of statins in the treatment of vitiligo is controversial.

AIM AND OBJECTIVE

We studied possible therapeutic effect of topical 1% niosomal atorvastatin ointment combined with topical 0.1% tacrolimus in treatment of non-segmental vitiligo.

METHODS

This is a triple blind, pilot, randomized placebo-controlled trial (RCT) that was performed in dermatology clinic. All the patients used topical 0.1% tacrolimus cream twice daily (BD). Moreover, the intervention group participants used topical 1% niosomal atorvastatin ointment, and control group participants were prescribed placebo ointment, BD. Patients were evaluated using vitiligo area surface index (VASI) score and patients' satisfaction at baseline and after 3 months treatment.

RESULTS

The mean patient satisfaction in the intervention and control groups were 5 ± 1.4 and 3.5 ± 1.9; the difference between groups was not statistically significant (p = 0.9). We found statistically significant difference in VASI score before and after treatment in both intervention and control groups (p = 0.01 and p = 0.03, respectively). However, comparison of the VASI score between groups was not statistically significant (p = 0.62). We also found no significant correlation between VASI score and other variables.

CONCLUSION

The result of this study indicates that adding of niosomal atorvastatin 1% ointment to topical calcineurin inhibitor has no additional effect on non-segmental type of vitiligo. Further large studies with different combinations are recommended before any conclusive result can be concluded on efficacy of statins in vitiligo.

Research Progress of Small Molecules as Anti-vitiligo Agents

Vitiligo is a disease characterized by skin discoloration, and no safe and effective drugs have been developed until now. New drug research and development are imminent. This article reviews the research on small-molecule drugs for vitiligo from 1990 to 2021 at home and abroad. They are classified according to their structures and mechanisms of action, including natural products and derivatives, anti-oxidative stress drugs, immunosuppressants, prostaglandins, etc. The research on their anti-vitiligo activity, structural modification, new dosage forms, clinical trials, and the development trend in new anti-vitiligo drugs are reviewed, which provides important references for the development of new drugs.

Biologic and targeted therapeutics in vitiligo

BACKGROUND

Vitiligo is a long-standing progressive autoimmune disease with depigmented macules/patches with significant psychological morbidity to the patients. From being one of the most poorly understood diseases in the past, there has been a rampant advance in determining the molecular and genetic factors influencing the disease process. More light has been shed on the complex intracellular environment and interplay between innate and adaptive immunity. Numerous cytokines and signaling pathways have been associated with disease pathogenesis in the recent past.

OBJECTIVE

The aim of this review the efficacy of biologic and targeted therapeutics in vitiligo.

METHODS

A detailed literature search was conducted on databases like PubMed, COCHRANE Central, EMBASE and Google Scholar using keywords-"biologics," "vitiligo," "treatment," "repigmentation," "JAK inhibitors,", "TNF-ꭤ inhibitors," and "IL17/23 inhibitors," Relevant studies and review articles in English were analyzed in detail and report was written. This article aimed at a comprehensive review of all the biologicals and newer targeted therapeutics tried in vitiligo and their efficacy with an insight into the potential complications arising as a result of the therapy.

RESULTS

Most conventional vitiligo treatment modalities are restricted to generalized nonspecific immunosuppressants like topical and oral corticosteroids, calcineurin inhibitors, phototherapy, and surgical modalities. There have been reports and studies on the usage of biologicals in treating vitiligo. JAK inhibitors have shown good efficacy in vitiligo; however, it lacks substantial evidence in the form of randomized control trials. Similarly, the use of targeted therapeutics in treating vitiligo is substantiated by limited evidence and requires more randomized trials for further evidence.

CONCLUSION

JAK inhibitors have shown promising results and good tolerability; Adjuvant phototherapy can achieve a superior response compared to monotherapy. Though TNF-ꭤ has been tried in a few cases, it is best used if vitiligo is present in association with other chronic autoimmune diseases for which it is indicated. More in vitro studies and clinical research are required to understand the pathogenesis clearly, and therapy has to be targeted at specific pathways for a better approach toward vitiligo. Treatment aimed at induction and differentiation of melanocytes may be added to achieve faster repigmentation.

Immunometabolism in the pathogenesis of vitiligo

Vitiligo is a common depigmenting skin disorder characterized by the selective loss of melanocytes. Autoimmunity, genetic, environmental, and biochemical etiology have been proposed in vitiligo pathogenesis. However, the exact molecular mechanisms of vitiligo development and progression are unclear, particularly for immunometabolism. Sporadic studies have suggested mitochondrial dysfunction, enhanced oxidative stress, and specific defects in other metabolic pathways can promote dysregulation of innate and adaptive immune responses in vitiligo. These abnormalities appear to be driven by genetic and epigenetic factors modulated by stochastic events. In addition, glucose and lipid abnormalities in metabolism have been associated with vitiligo. Specific skin cell populations are also involved in the critical role of dysregulation of metabolic pathways, including melanocytes, keratinocytes, and tissue-resident memory T cells in vitiligo pathogenesis. Novel therapeutic treatments are also raised based on the abnormalities of immunometabolism. This review summarizes the current knowledge on immunometabolism reprogramming in the pathogenesis of vitiligo and novel treatment options.

Updates and new medical treatments for vitiligo (Review)

Vitiligo is a multifactorial disease characterized by the loss of skin pigment, which results in achromic macules and patches. There are currently several medical treatments available, which aim to arrest progression and induce skin repigmentation. These treatments alone or combined have exhibited varying degrees of pigmentation, and the majority are safe and effective. All therapies for vitiligo are limited, and no known treatment can consistently produce repigmentation in all patients. Individualized treatment is appropriate according to the location, clinical presentation and the presence of disease activity. The present review summarizes the medical treatments available for vitiligo: Systemic and topic pharmacological therapies, physical and depigmentation treatments. Several treatments are still underway and have not yet been approved. However, due to the promising preliminary results, these are also mentioned in the present review.

Vitiligo: The Association With Metabolic Syndrome and the Role of Simvastatin as an Immunomodulator

Vitiligo is an autoimmune condition primarily affecting the skin where there is destruction of melanocytes characterized by pinkish-white patches on the skin. It is associated with other autoimmune diseases such as thyroid disease, rheumatoid arthritis, diabetes mellitus, and metabolic syndrome. Metabolic syndrome is a constellation of disorders including insulin resistance, hypertension, dyslipidemia, and obesity, and is considered a leading cause of cardiovascular morbidity. Simvastatin is a potent hypolipidemic drug that also possesses immunomodulating properties and is a common drug used in dyslipidemia and cardiovascular diseases. This study aimed to assess the association between vitiligo and metabolic syndrome and explore the immunomodulating properties of simvastatin for use in vitiligo. We reviewed various articles from PubMed, ResearchGate, and Google Scholar using different keywords and Medical Subject Headings and finalized 33 studies to be used in our review. The articles selected showed a positive association between vitiligo and metabolic syndrome or one of the component diseases of metabolic syndrome. The benefits of using simvastatin were also addressed by few articles attributing to its antioxidant and immunomodulating effect. However, there was no concrete explanation justifying the association between vitiligo and metabolic syndrome due to a limited number of studies and smaller sample size. Large-scale clinical trials should be conducted to evaluate the use of simvastatin as an immunomodulator in vitiligo to prevent possible metabolic complications.

Simvastatin in vitiligo: an update with recent review of the literature

Patients with vitiligo often seek medical attention, as it diminishes their quality of life resulting in significant morbidity. Several topical and systemic therapies are in vogue targeting the immunological aspect of this disease, but results are often unsatisfactory, and complete cure remains elusive. Recently, simvastatin, a 3-hydroxy-3-methylyglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, is being evaluated for vitiligo management because of its multimodal action, easy availability, and low cost. The proposed multimodal actions range from anti-inflammatory, antioxidant, to immunomodulatory properties which may be of therapeutic benefit in vitiligo patients. The authors intend to evaluate the role of simvastatin as a novel therapeutic agent for vitiligo along with relevant review of literature.

Nuclear factor erythroid 2-related factor 2 (Nrf2) as a potential therapeutic target for vitiligo

Vitiligo is an autoimmune disease of the skin which causes loss of melanocytes from the epidermis. Recently, it is demonstrated that oxidative stress (OS) plays a significant role in the immuno-pathogenesis of vitiligo. A major mechanism in the cellular defense against OS is activation of the nuclear factor erythroid2-related factor (Nrf2)-Kelch-like ECH-associated protein 1(Keap1)-antioxidant responsive element (ARE) signaling pathway. Recently it has been shown that vitiligo melanocytes have impaired Nrf2-ARE signaling. A number of drugs including those known as Nrf2 activators and those known to possess effects to activate Nrf2, have been used in treating vitiligo with certain therapeutic effects. Also, studies have shown that a number of compounds can protect melanocytes against OS via activating Nrf2. These compounds may be considered as candidates for developing new drugs for vitiligo in the future. Nrf2 can be considered as a potential therapeutic target for vitiligo.

Efficacy and safety of oral simvastatin in the treatment of patients with vitiligo

Vitiligo, an autoimmune disease, is a depigmentation skin disorder characterized by hypopigmentation spots and patches that are difficult to treat. The purpose of this study is to analyze the clinical efficacy of simvastatin in the treatment of vitiligo. From December 2016 to October 2019, five vitiligo patients from Peking Union Medical College Hospital were treated with simvastatin and tacrolimus. For simvastatin, the first three patients (patient 1, patient 2, and patient 3) began to take 40 mg/day, and the latter two patients began to take 20 mg/day. From week 5, patients 1 and 2 received 20 mg simvastatin once a day. And the 0.1% tacrolimus ointment was used topically. The response was measured using the Vitiligo European Task Force (VETF) scoring system at baseline and at the fourth and eighth weeks of treatment. The results of the VETF score showed that three of the patients achieved significant clinical efficacy. There was no significant improvement in the other two cases. No serious acute or chronic side effects were observed. In conclusion, our results suggest that conventional oral simvastatin is safe, although it may not be effective in the treatment of vitiligo.

Higher incidence of metabolic syndrome components in vitiligo patients: a prospective cross-sectional study

BACKGROUND/OBJECTIVES

To investigate the association between vitiligo and metabolic syndrome.

METHODS

A prospective cross-sectional study was conducted between 2014 and 2016. Study (n=155) and control groups (n=155) were evaluated for metabolic syndrome according to National Cholesterol Education Program Adult Treatment Panel III and the International Diabetes Federation criteria. Study group was divided into three groups according to their vitiligo area severity index and vitiligo disease activity score values (Group 1: 6.89 for VASI score, Group A: -1-0, Group B: 1-2 and Group C: 3-4 for vitiligo disease activity score respectively). MetS rates according to both criteria were compared between the vitiligo disease activity score and vitiligo area severity index groups.

RESULTS

Metabolic syndrome rates were 37.4% and 40% in the study group and 19.4% and 26.5% in the control group according to National CholesterolEducation Program Adult Treatment Panel III and International Diabetes Federation criteria, respectively (p<001 and p=0.011). Metabolic syndrome was more frequent in vitiligo area severity index Groups 2 and 3 compared to vitiligo area severity index Group 1, and in vitiligo disease activity score Group C compared to vitiligo disease activity score Groups A and B.

STUDY LIMITATIONS

Single center experience, absence of more specific oxidative-stress markers and lack of long-term follow-up of the patients.

CONCLUSIONS

Frequency of metabolic syndrome was higher in patients with non-segmental vitiligo and the rate was higher in active/severe form of the disease.

Emerging drugs for the treatment of vitiligo

Introduction: Vitiligo is a relatively common autoimmune depigmenting disorder of the skin. There has been a great advance in understanding the pathological basis, which has led to the development and utilization of various new molecules in treating vitiligo. This review aims at a comprehensively describing the treatments available and the emerging treatment aspects and the scope for future developments.Areas covered: This study comprehensively summarizes the current concepts in the pathogenesis of vitiligo with special focus on the cytokine and signaling pathways, which are the targets for newer drugs. JAK kinase signaling pathways and the cytokines involved are the focus of vitiligo treatment in current research, followed by antioxidant mechanisms and repigmenting mechanisms. Topical immunosuppressants may be an alternative to steroids in localized vitiligo. Newer repigmenting agents like basic fibroblast growth factors, afamelanotide have been included and a special emphasis is laid on the upcoming targeted immunotherapy.Expert opinion: The treatment of vitiligo needs to be multimodal with emphasis on targeting different limbs of the pathogenesis. Topical and oral JAK inhibitors are the most promising new class of drugs currently available for treating vitiligo and acts best in conjunction with NB-UVB.

Sodium tanshinone IIA silate increases melanin synthesis by activating the MAPK and PKA pathways and protects melanocytes from H2O2-induced oxidative stress

Vitiligo is an intriguing depigmentation disorder that affects about 0.5–2% of the world population. In the past decade, first-line treatments of vitiligo have involved the use of calcineurin inhibitors and corticosteroids. Sodium tanshinone IIA sulfonate (STS) has been widely applied in the treatment of cardiovascular and cerebrovascular diseases in China. In the present study, the effect of STS on melanogenesis was confirmed in the B16F10 cells and zebrafish by direct observation. The prevention of hydrogen peroxide (H₂O₂)-induced oxidative stress has been proven to be beneficial to vitiligo patients, and STS that can protect the B16F10 cells against oxidative stress has been investigated in the present reversed study. Moreover, we found that pre-treatment with STS led to a concentration-dependent mitochondrial impairment and decreased cell apoptosis of the B16F10 cells in response to H₂O₂. In addition, we demonstrated that STS increased melanin synthesis in the B16F10 cells by activating the mitogen-activated protein kinase (MAPK) and protein kinase A (PKA) pathways. STS also increased the Cdc42 and KIF5b expression to stimulate the translocation of melanin. These results suggest that STS protects the B16F10 cells against H₂O₂-induced oxidative stress and exerts melanin synthesis activity in the B16F10 cells by activating the MAPK and PKA pathways; thus, it shows therapeutic potential for vitiligo.

Vitiligo is an intriguing depigmentation disorder that affects about 0.5–2% of the world population.

Metabolic syndrome in vitiligo patients among a semi-urban Maharashtrian population: A case control study

AIM

To assess the prevalence of metabolic syndrome and its correlation with the severity and duration of vitiligo.

METHODS

One hundred vitiligo patients and 100 age-and-sex matched controls were included, whose waist circumference and blood pressure were measured; fasting serum cholesterol, triglycerides and glucose levels quantified; disease severity assessed and metabolic syndrome defined by National Cholesterol Education Program (NCEP) criteria.

RESULTS

Metabolic syndrome (24%:12%), hypertriglyceridemia (41%:24%), impaired glucose tolerance (25%:16%) [P<0.05] and low HDL (P=0.044) were significantly more prevalent in cases as compared to controls as were the mean values of triglycerides and fasting blood sugar. Increased mean age of vitiligo patients correlated with the presence of metabolic syndrome.

CONCLUSION

Metabolic syndrome had significant presence in but remained unaffected by the severity of vitiligo in our study patients.

Increased Risk of Metabolic Syndrome in Patients with Vitiligo

Background:

Inflammatory and immune processes can be triggered in vitiligo due to a decreased number of melanocytes and their anti-inflammatory effects. Because of the systemic nature of vitiligo, metabolic abnormalities such as insulin resistance and lipid profile disturbances as well as skin involvement may be observed in vitiligo.

Aims:

To investigate the association between metabolic syndrome and vitiligo.

Study Design:

Case-control study.

Methods:

The demographic, clinical and laboratory features in the subjects were compared according to presence of vitiligo and metabolic syndrome [patients (n=63) vs. gender-age matched controls (n=65) and metabolic syndrome positive (n=38) vs. negative (n=90)]. A logistic regression analysis was also used.

Results:

We identified metabolic syndrome in 24 (38.1%) subjects with vitiligo and 14 (21.5%) subjects without vitiligo (p=0.04). Active vitiligo, segmental vitiligo, an increased duration of vitiligo and an increased percentage in the affected body surface area were determined to be independent predictors of metabolic syndrome [activity of vitiligo: p=0.012, OR (95% CI)=64.4 (2.5-1672); type of vitiligo: p=0.007, OR (95% CI)=215.1 (4.3-10725.8); duration of vitiligo: p=0.03, OR (95% CI)=1.4 (1.1-2.0); percentage of affected body surface area: p=0.07, OR (95% CI)=1.2 (0.98-1.5)].

Conclusion:

The risk of developing metabolic syndrome is increased in patients with vitiligo. The poor clinical features of vitiligo, such as active, extended and segmental vitiligo with an increased duration of time, are independent predictors for developing metabolic syndrome.

Vitiligo Pathogenesis and Emerging Treatments

The pathogenesis of vitiligo involves interplay between intrinsic and extrinsic melanocyte defects, innate immune inflammation, and T-cell-mediated melanocyte destruction. The goal of treatment is to not only halt disease progression but also promote repigmentation through melanocyte regeneration, proliferation, and migration. Treatment strategies that address all aspects of disease pathogenesis and repigmentation are likely to have greatest efficacy, a strategy that may require combination therapies. Current treatments generally involve nontargeted suppression of autoimmunity, whereas emerging treatments are likely to use a more targeted approach based on in-depth understanding of disease pathogenesis, which may provide higher efficacy with a good safety profile.

A Comparison of Betamethasone Valerate 0.1% Cream Twice Daily Plus Oral Simvastatin Versus Betamethasone Valerate 0.1% Cream Alone in the Treatment of Vitiligo Patients

BACKGROUND

Vitiligo, a common disorder of depigmentation, is often difficult to treat. Corticosteroids are known to be effective, but with modest results. Although simvastatin has been reported to be effective for immunorelated dermatologic disorders including vitiligo, controlled trials are lacking. This study was conducted to compare the efficacy of topical betamethasone valerate 0.1% cream (as a standard method of treatment for vitiligo) versus a combination of betamethasone valerate plus oral simvastatin in the treatment of vitiligo.

MATERIALS AND METHODS

Eighty-eight subjects with symmetric vitiligo who had body surface involvement up to 20% were divided randomly into two groups. Group A were treated with betamethasone valerate 01% cream twice daily and Group B with betamethasone valerate 01% cream twice daily and oral simvastatin 80 mg daily for 12 weeks. Finally, 46 patients completed treatment after 12 weeks in both groups. The results were evaluated by a blind dermatologist using Vitiligo Area Scoring Index (VASI) score at baseline, 4th, 8th, and 12th week of treatment. In a similar way, subjective assessment performed by patients based on photo evaluation at the end of the study.

RESULTS

Despite a continuous reduction in VASI score in both groups, according to both physician (P = 0.13) and patient (P = 0.374) assessment oral simvastatin was not statistically more effective than conventional treatment of vitiligo.

CONCLUSION

This study indicates that oral simvastatin is not associated with significant impacts in the treatment of vitiligo as compared to other inflammatory dermatologic conditions such as psoriasis. Indeed, other studies should be initiated regarding exact molecular and cellular effects of statins in the treatment of vitiligo.

Simvastatin Protects Human Melanocytes from H2O2-Induced Oxidative Stress by Activating Nrf2

The prevention of hydrogen peroxide (H₂O₂)-induced oxidative stress has proved to be beneficial to vitiligo patients. Simvastatin possesses antioxidative capacity and has shown protective effect in various oxidative stress-related diseases. However, whether simvastatin can protect human melanocytes against oxidative stress has not been investigated. In this study, we initially found that pretreatment with 0.1 μmol/L to 1.0 μmol/L simvastatin led to increased cell viability and decreased cell apoptosis of melanocytes in response to H₂O₂. In addition, simvastatin was able to potentiate the activity of antioxidant enzymes and lessen intracellular reactive oxygen species accumulation. Furthermore, we found that simvastatin promoted the activation of nuclear erythroid 2-related factor (Nrf2) and that knockdown of Nrf2 abolished the protective effect of simvastatin against H₂O₂-induced oxidative damage. More importantly, the mutual enhancement between mitogen-activated protein kinase pathways and p62 contributed to simvastatin-induced Nrf2 activation in melanocytes. Finally, simvastatin showed more antioxidative capacity and better protective effect than aspirin in H₂O₂-treated melanocytes. Taken together, our results show that simvastatin protects human melanocytes from H₂O₂-induced oxidative stress by activating Nrf2, thus supporting simvastatin as a potential therapeutic agent for vitiligo.

Advances in Vitiligo: An Update on Medical and Surgical Treatments

Vitiligo is one of the most common cutaneous disorders of depigmentation. Although its underlying causes are still being studied and no definitive cure currently exists, recent research has provided insight into pathogenic mechanisms and new treatment options. Objective: The aim of this paper is to provide a comprehensive overview of the medical and surgical therapies for vitiligo with emphasis on the most recent treatment modalities. Design: This review was conducted through a literature search using PubMed and the National institutes of Health's clinicalTrials.gov databases from January 2010 to July 2015. This yielded 86 studies, 12 of which were excluded, and 74 of which were reviewed. Results: Recent studies and ongoing clinical trials indicate that there are many promising new medical and surgical treatment modalities for this chronic condition. Conclusion: A combination of traditional and newer treatments may work synergistically to provide additional improvement in patients' disease state and quality of life.

Understanding mechanisms of autoimmunity through translational research in vitiligo

Vitiligo is an autoimmune disease of the skin that leads to life-altering depigmentation and remains difficult to treat. However, clinical observations and translational studies over 30-40 years have led to the development of an insightful working model of disease pathogenesis: Genetic risk spanning both immune and melanocyte functions is pushed over a threshold by known and suspected environmental factors to initiate autoimmune T cell-mediated killing of melanocytes. While under cellular stress, melanocytes appear to signal innate immunity to activate T cells. Once the autoimmune T cell response is established, the IFN-γ-STAT1-CXCL10 signaling axis becomes the primary inflammatory pathway driving both progression and maintenance of vitiligo. This pathway is a tempting target for both existing and developing pharmaceuticals, but further detailing how melanocytes signal their own demise may also lead to new therapeutic targets. Research in vitiligo may be the future key to understand the pathogenesis of organ-specific autoimmunity, as vitiligo is common, reversible, progresses over the life of the individual, has been relatively well-defined, and is quite easy to study using translational and clinical approaches. What is revealed in these studies can lead to innovative treatments and also help elucidate the principles that underlie similar organ-specific autoimmune diseases, especially in cases where the target organ is less accessible.

Recent advances in understanding vitiligo

Vitiligo, an acquired depigmentation disorder, manifests as white macules on the skin and can cause significant psychological stress and stigmatization. Recent advances have shed light on key components that drive disease onset and progression as well as therapeutic approaches. Vitiligo can be triggered by stress to the melanin pigment-producing cells of the skin, the melanocytes. The triggers, which range from sunburn to mechanical trauma and chemical exposures, ultimately cause an autoimmune response that targets melanocytes, driving progressive skin depigmentation. The most significant progress in our understanding of disease etiology has been made on three fronts: (1) identifying cellular responses to stress, including antioxidant pathways and the unfolded protein response (UPR), as key players in disease onset, (2) characterizing immune responses that target melanocytes and drive disease progression, and (3) identifying major susceptibility genes. The current model for vitiligo pathogenesis postulates that oxidative stress causes cellular disruptions, including interruption of protein maturation in the endoplasmic reticulum (ER), leading to the activation of the UPR and expression of UPR-regulated chemokines such as interleukin 6 (IL-6) and IL-8. These chemokines recruit immune components to the skin, causing melanocytes to be targeted for destruction. Oxidative stress can further increase melanocyte targeting by promoting antigen presentation. Two key components of the autoimmune response that promote disease progression are the interferon (IFN)-γ/CXCL10 axis and IL-17-mediated responses. Several genome-wide association studies support a role for these pathways, with the antioxidant gene NRF2, UPR gene XBP1, and numerous immune-related genes including class I and class II major histocompatibility genes associated with a risk for developing vitiligo. Novel approaches to promote repigmentation in vitiligo are being investigated and may yield effective, long-lasting therapies.

Understanding autoimmunity of vitiligo and alopecia areata

PURPOSE OF REVIEW

Vitiligo and alopecia areata are common, disfiguring skin diseases. Treatment options are limited and include nontargeted approaches, such as corticosteroids, topical calcineurin inhibitors, narrow band ultraviolet B phototherapy, and other immune-modifying agents. The purpose of this article is to review shared, novel mechanisms between vitiligo and alopecia areata, as well as discuss how they inform the development of future targeted treatments.

RECENT FINDINGS

Vitiligo and alopecia areata are both autoimmune diseases, and striking similarities in pathogenesis have been identified at the level of both the innate and adaptive immune system. Increased reactive oxygen species and high cellular stress level have been suggested as the initiating trigger of the innate immune system in both diseases, and genome-wide association studies have implicated risk alleles that influence both innate and adaptive immunity. Most importantly, mechanistic studies in mouse models of vitiligo and alopecia areata have specifically implicated an interferon (IFN)γ-driven immune response, including IFNγ, IFNγ-induced chemokines, and cytotoxic CD8 T cells as the main drivers of disease pathogenesis. These recent discoveries may reveal an effective strategy to develop new treatments, and several proof-of-concept clinical studies support this hypothesis.

SUMMARY

The identification of IFNγ-driven immune signaling pathways has enabled discoveries of potential new treatments for vitiligo and alopecia areata, and supports initiation of larger clinical trials.

Simvastatin prevents and reverses depigmentation in a mouse model of vitiligo

Vitiligo is a common autoimmune disease of the skin that results in disfiguring white spots. There are no FDA-approved treatments, and current treatments are time-consuming, expensive, and have low efficacy. We sought to identify new treatments for vitiligo, and first considered repurposed medications because of the availability of safety data and expedited regulatory approval. We previously reported that the IFN-γ-induced chemokine CXCL10 is expressed in lesional skin from vitiligo patients, and that it is critical for the progression and maintenance of depigmentation in our mouse model of vitiligo. We hypothesized that targeting IFN-γ signaling might be an effective new treatment strategy. STAT1 activation is required for IFN-γ signaling and recent studies revealed that simvastatin, an FDA-approved cholesterol-lowering medication, inhibited STAT1 activation in vitro. Therefore, we hypothesized that simvastatin may be an effective treatment for vitiligo. We found that simvastatin both prevented and reversed depigmentation in our mouse model of vitiligo, and reduced the number of infiltrating autoreactive CD8⁺ T cells in the skin. Treatment of melanocyte-specific, CD8⁺ T cells in vitro decreased proliferation and IFN-γ production, suggesting additional effects of simvastatin directly on T cells. Based on these data, simvastatin may be a safe, targeted treatment option for patients with vitiligo.

Statins in dermatology

Statins are competitive inhibitors of 3-hydroxy-3-methylyglutaryl-coenzyme A reductase and reduce low-density lipoprotein-C levels. Statins are well-tolerated drugs used for prevention of atherosclerosis and cardiovascular events. Statins possess anti-inflammatory, immunomodulatory, antioxidant, metabolic, and possible anticancer effects. Statins are reported to be effective against psoriasis, dermatitis, graft-versus-host disease, uremic pruritus, vitiligo, and hirsutism. Topical forms of statins are employed in the treatment of acne, seborrhea, rosacea, and rhinophyma. Animal studies show the beneficial effect of statins against contact dermatitis and wound healing. They have promising anti-HIV effects as well. This article succinctly reviews the various cellular and molecular effects of statins, their applications in cutaneous medicine and their side effects.

Statin adverse effects : a review of the literature and evidence for a mitochondrial mechanism

HMG-CoA reductase inhibitors (statins) are a widely used class of drug, and like all medications, have potential for adverse effects (AEs). Here we review the statin AE literature, first focusing on muscle AEs as the most reported problem both in the literature and by patients. Evidence regarding the statin muscle AE mechanism, dose effect, drug interactions, and genetic predisposition is examined. We hypothesize, and provide evidence, that the demonstrated mitochondrial mechanisms for muscle AEs have implications to other nonmuscle AEs in patients treated with statins. In meta-analyses of randomized controlled trials (RCTs), muscle AEs are more frequent with statins than with placebo. A number of manifestations of muscle AEs have been reported, with rhabdomyolysis the most feared. AEs are dose dependent, and risk is amplified by drug interactions that functionally increase statin potency, often through inhibition of the cytochrome P450 3A4 system. An array of additional risk factors for statin AEs are those that amplify (or reflect) mitochondrial or metabolic vulnerability, such as metabolic syndrome factors, thyroid disease, and genetic mutations linked to mitochondrial dysfunction. Converging evidence supports a mitochondrial foundation for muscle AEs associated with statins, and both theoretical and empirical considerations suggest that mitochondrial dysfunction may also underlie many nonmuscle statin AEs. Evidence from RCTs and studies of other designs indicates existence of additional statin-associated AEs, such as cognitive loss, neuropathy, pancreatic and hepatic dysfunction, and sexual dysfunction. Physician awareness of statin AEs is reportedly low even for the AEs most widely reported by patients. Awareness and vigilance for AEs should be maintained to enable informed treatment decisions, treatment modification if appropriate, improved quality of patient care, and reduced patient morbidity.