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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Serum Inflammatory and Oxidative Stress Markers in Patients with Vitiligo

BACKGROUND

Vitiligo is a common chronic hypomelanotic skin disorder. An intricate pool of markers associated with a complex combination of biological and environmental factors is thought to be implicated in etiology. This study aims to investigate the most important markers associated with vitiligo pathogenesis, including redox status, inflammation, and immune profile, in patients with vitiligo.

MATERIALS AND METHODS

The study included a total of 96 subjects: 30 patients with active non-segmental vitiligo, 30 patients with stable non-segmental vitiligo, and 36 controls. The vitiligo area severity index (VASI) and vitiligo disease activity score (VIDA) were determined. The following serum parameters were assessed: antioxidant status (TAS), superoxide dismutase activity (SOD), catalase activity (CAT), glutathione peroxidase activity (GPx), glutathione-S-transferase activity (GST), malondialdehyde (MDA), advanced oxidation protein products (AOPP), C reactive protein (CRP), interleukin-15 (IL-15), and chemokines (CXCL9, CXCL10).

RESULTS

The VASI score was not significantly different between active and stable vitiligo patients, as it was approximately 0.1. TAS, CAT, GPx, and GST were significantly lower in vitiligo patients compared to controls (p < 0.05). They were also significantly lower in active vitiligo when compared to stable vitiligo (p < 0.05). However, SOD levels were significantly higher in vitiligo patients than in controls and in the active vitiligo group than in the stable vitiligo group (p < 0.05). MDA and AOPP levels were significantly higher in patients with active and stable vitiligo compared to controls (p < 0.05). However, they did not significantly differ between active and stable vitiligo patients (p < 0.05). In both active and stable vitiligo, CRP and IL-15 were significantly higher than controls (p < 0.05). Whereas CRP was significantly higher in active (range = 2.0-7.2, mean = 4.46 ± 1.09) than in stable vitiligo (range = 1.6-6.7, mean = 3.75 ± 1.08) (p < 0.05). There was no significant difference in IL-15 levels between active and stable vitiligo. In both active and stable vitiligo, CXCL9 and CXCL10 were significantly higher than controls (p < 0.05), and they were significantly higher in active than stable vitiligo (p < 0.05).

CONCLUSIONS

In vitiligo, oxidative damage induces an increase in pro-inflammatory IL-15, which in turn promotes IFN-γ-inducible chemokines such as CXCL9 and CXCL10. Further, there seems to be a link between the VASI score and IL-15 levels. These data imply that inhibiting IL-15 could be a promising method for developing a potentially targeted treatment that suppresses the early interplay between oxidant stress and IL-15 keratinocyte production, as well as between resident and recirculating memory T cells.

The analyse of the antioxidant effect of natural peloidotherapy in aging process

Medical research has developed remarkably in recent years, including the involvement of the glutathione peroxidase (GPx) family of enzymes in the course of human aging, with numerous clinical studies published in the literature reporting this particular fact. Thus, mud therapy and its effect on biological aging have been represented in papers that have been published to date. Papers published in the literature analyzing GPx vari-ation during sapropelic mud therapy suggest the beneficial effect of this family of en-zymes in diseases with an important inflammatory component, mainly monitored in patients with osteoarthritis. This study investigated the effects of sapropelic mud treat-ment on GPx values in patients receiving treatment with sapropelic mud at the Balneal and Rehabilitation Sanatorium of Techirghiol, Romania. We included 52 patients, split into two groups, who received treatment with cold mud baths and warm mud baths. Values close to statistical significance were found in patients who received treatment with cold mud baths in terms of mean GPx values at the four-time points studied. Fur-ther studies evaluating GPx in patients receiving sapropelic mud treatment are needed.

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

Vitiligo is an acquired hypopigmentation of the skin due to a progressive selective loss of melanocytes; it has a prevalence of 1-2% and appears as rounded, well-demarcated white macules. The etiopathology of the disease has not been well defined, but multiple factors contribute to melanocyte loss: metabolic abnormalities, oxidative stress, inflammation, and autoimmunity. Therefore, a convergence theory was proposed that combines all existing theories into a comprehensive one in which several mechanisms contribute to the reduction of melanocyte viability. In addition, increasingly in-depth knowledge about the disease's pathogenetic processes has enabled the development of increasingly targeted therapeutic strategies with high efficacy and fewer side effects. The aim of this paper is, by conducting a narrative review of the literature, to analyze the pathogenesis of vitiligo and the most recent treatments available for this condition.

Natural polyphenols: a promising bioactive compounds for skin care and cosmetics

The physiological and morphological aspects of skin suffer from frequent change. Numerous internal and external factors have direct impact on inducing various skin problems like inflammation, aging, cancer, oxidative stress, hyperpigmentation etc. The use of plant polyphenols as a photo-ecting agent is gaining popularity nowadays. Polyphenols are known to enhance endogenic antioxidant system of skin thereby preventing various skin diseases. The biological activity of plant polyphenols is dependent on their physicochemical properties for overcoming the epidermal barriers to reach the specific receptor. Several evidences have reported the vital role polyphenols in mitigating adverse skin problems and reverting back the healthy skin condition. The interest in plant derived skin care products is emerging due to the changing notion of people to shift their focus towards use of plant-based products. The present review draws an attention to uncover the protective role of polyphenols in prevention of various skin problems. Several in vitro and in vivo studies have been summarized that claims the efficacious nature of plant extract having dermatological significance.

Update on the pathogenesis of vitiligo

Vitiligo is a complex disease whose pathogenesis results from the interaction of genetic components, metabolic factors linked to cellular oxidative stress, melanocyte adhesion to the epithelium, and immunity (innate and adaptive), which culminate in aggression against melanocytes. In vitiligo, melanocytes are more sensitive to oxidative damage, leading to the increased expression of proinflammatory proteins such as HSP70. The lower expression of epithelial adhesion molecules, such as DDR1 and E-cadherin, facilitates damage to melanocytes and exposure of antigens that favor autoimmunity. Activation of the type 1-IFN pathway perpetuates the direct action of CD8+ cells against melanocytes, facilitated by regulatory T-cell dysfunction. The identification of several genes involved in these processes sets the stage for disease development and maintenance. However, the relationship of vitiligo with environmental factors, psychological stress, comorbidities, and the elements that define individual susceptibility to the disease are a challenge to the integration of theories related to its pathogenesis.

Herb Sanqi-Derived Compound K Alleviates Oxidative Stress in Cultured Human Melanocytes and Improves Oxidative-Stress-Related Leukoderma in Guinea Pigs

Sanqi, a traditional Chinese herb, is widely used for cardiovascular diseases, and its neuroprotective effects against oxidative stress were recently discovered. The purpose of this study was to investigate whether Sanqi-derived compound K (Sanqi-CK), an active metabolite of Sanqi, could protect melanocytes from oxidative stress. Cultured human primary skin epidermal melanocytes (HEMn-MPs) were treated with hydrogen peroxide (H₂O₂) in the presence or absence of Sanqi-CK. Sanqi-CK exhibited protective effects against H₂O₂-induced cell death by reducing oxidative stress. In addition, treatment with Sanqi-CK reversed the decreased glutathione reductase activity and decreased ratio of reduced glutathione (GSH)/oxidized glutathione (GSSG) seen in H₂O₂-treated melanocytes. Furthermore, topical application of Sanqi-CK alleviated leukoderma in guinea pigs, a disorder characterized by melanocyte cell death resulting from rhododendrol-induced oxidative stress. Taken together, these data suggest that Sanqi-CK protects melanocytes against oxidative stress, and its protective effects are associated with modulating the redox balance between GSH and GSSG and activating glutathione reductase. Thus, Sanqi-CK may be a good candidate for preventing melanocyte loss in oxidative-stress-associated pigmentary disorders.

Paeonol protects melanocytes against hydrogen peroxide-induced oxidative stress through activation of Nrf2 signaling pathway

Oxidative stress plays a pivotal role in the pathogenesis of vitiligo. Paeonol, a phenolic compound found in the root bark of Cortex Moutan, has been suggested to have therapeutic effects on various diseases through nuclear factor Nrf2 mediated antioxidant pathways. However, the therapeutic effects of paeonol on vitiligo have not been investigated. In this study, we investigated whether paeonol could protect melanocytes against oxidative stress through Nrf2 activation. Hydrogen peroxide (H₂ O₂ ) was used to mimic the oxidative stress. PIG1 cells were pretreated with paeonol for 24 h, and then were treated with H₂ O₂ for 24 h. To detect the role of Nrf2, siRNA method was used to knockdown the Nrf2 expression. After that, cell viability, melanin content, tyrosinase activity, intracellular reactive oxygen species, antioxidant enzymes activities, nuclear translocation of Nrf2, and mRNA expression of Nrf2 downstream antioxidant genes were detected. Paeonol improved cell viability and melanogenesis in PIG1 cells treated with H₂ O₂ . Paeonol also alleviated oxidative stress by restoring the activities of superoxide dismutase, catalase, and glutathione peroxidase. Paeonol promoted Nrf2 nuclear translocation and the expression of its downstream-regulated antioxidative genes under oxidative stress. Furthermore, Nrf2 knockdown by siRNA abolished the protective effects of paeonol on PIG1 cells against oxidative damage. Paeonol protected melanocytes against H₂ O₂ -induced oxidative stress by Nrf2 mediated antioxidant pathways. Paeonol is a potential therapeutic drug for vitiligo.

Use of a Spinal Thermal Massage Device for Anti-oxidative Function and Pain Alleviation

Background: Elderly people are vulnerable to a variety of diseases, including chronic pain, which reduces their levels of physical fitness. Thermal massage has been shown to relieve pain and activate antioxidant enzymes. The objective of this study was to determine whether thermal massaging of the spinal column can reduce muscle pain and induce antioxidant function.

Methods: This study included participants aged ≥60 years with lower back pain. The participants were assigned to either an experimental group who received spinal column thermal massage and standard rehabilitative treatment or a control group who received standard rehabilitative treatment only. Data from a total of 116 participants (61 and 55 in the control and experimental groups, respectively) were used for analysis. Participants were assessed before treatment and at 4 (POST1) and 8 weeks (POST2) post-treatment, using a pain numeric rating scale (PNRS) and the Roland and Morris Disability Questionnaire (RMDQ), and by measuring the serum levels of superoxide dismutase (SOD), serum glutathione-peroxidase (GPx), and serum catalase (CAT).

Results: The extent of pain reduction, as measured by the PNRS, was greater in the experimental group. The RMDQ score in the control group decreased at POST1, but the decrease was not maintained at POST2, whereas the decrease in POST1 in the experimental group continued until POST2. SOD concentrations were significantly higher in the experimental group at POST1 and POST2, and GPx levels were significantly higher in the experimental group at POST2; however, there were no changes in CAT concentrations. Incidentally, there was a significant correlation between antioxidant activity and pain perception in the experimental group.

Conclusions: The study findings suggest that spinal column thermal massage reduces pain more effectively, improves self-reported levels of disability, and increases the antioxidant enzyme levels. Thermal massage may, therefore, be useful in the prevention and treatment of diseases associated with oxidation.

Vitiligo and Rise in Blood Pressure - a Case-Control Study in a Referral Dermatology Clinic in Southern Iran

Purpose

Vitiligo is an acquired hypopigmentation condition in which well-defined macules can develop virtually everywhere on the patients’ skin. This analytic case–control study was conducted in Faghihi Hospital outpatient dermatology clinic, affiliated to Shiraz University of Medical Sciences, southern Iran from June to September 2019. Furthermore, we studied the relationship of hypertension with activity, age of onset, duration, affected body surface area and type of vitiligo.

Patients and Methods

In the current case–control study, 166 individuals were enrolled in total (the case group was comprised of 83 vitiligo patients and 83 individuals actedas control group). The case group was made up of vitiligo patients (both segmental and non-segmental) between 20 and 50 years of age, no prior history of systemic disease and other hypopigmentation disorders, while individuals with any form of dermatologic findings were excluded from the control group. Individuals aged younger than 20 years old or older than 50, having a dermatologic disease other than vitiligo, being afflicted with the diseases which may lead to secondary hypertension, pregnancy, taking substances, and medication which can lead to hypertension were chosen as the exclusion criteria in this study.

Results

Data obtained from our study revealed that vitiligo patients had a higher prevalence of essential hypertension diagnosis than the control group (P=0.040). Also, no significant relationship was found between patients’ age at the first lesion appearance (P=0.856), duration of vitiligo involvement (P=0.497), and percentage of vitiligo involvement (P=0.681) with hypertension.

Conclusion

According to our results, vitiligo patients were more susceptible to hypertension while no association could be found between characteristics of the disease and rise in blood pressure.

Association between vitiligo and smoking: A nationwide population-based study in Korea

No study has examined the associations between vitiligo and smoking. The purpose of this study was to investigate the incidence of vitiligo according to smoking status. We used clinical data from individuals aged over 20 years who received a health examination in the National Insurance Program between 2009 and 2012 (n = 23,503,807). We excluded individuals with pre-existing vitiligo who had ever been diagnosed with vitiligo before the index year (n = 35,710) or who were diagnosed with vitiligo within a year of the index year (n = 46,476). Newly diagnosed vitiligo was identified using claims data from baseline to date of diagnosis or December 31, 2016 (n = 22,811). The development of vitiligo was compared according to self-reported smoking status by a health examination survey. The hazard ratio of vitiligo in current smokers was 0.69 (95% confidence interval; 0.65-0.72) with a reference of never-smokers after adjustment for age, sex, regular exercise, drinking status, body mass index, diabetes mellitus, hypertension, dyslipidemia, history of stroke, and history of ischemic heart diseases. The decreased risk of vitiligo in current smokers persisted after subgroup analysis of sex and age groups. The results suggested there are suppressive effects of smoking on the development of vitiligo. Further studies are needed to evaluate the mechanism of smoking on the development of vitiligo.

Ginkgo biloba extract protects human melanocytes from H2 O2 -induced oxidative stress by activating Nrf2

Vitiligo is a common skin depigmenting disorder characterized by the loss of functional melanocytes. Its pathogenesis is complicated and oxidative stress plays a critical role in the development of vitiligo. Thus, antioxidant therapy is a promising therapeutic strategy to prevent or even reverse the progression of depigmentation. Ginkgo biloba extract EGb761 has been confirmed to have protective effects on neurons against oxidative stress. Notably, several clinical trials have shown that patients with stable vitiligo achieved repigmentation after taking EGb761. However, the exact mechanism underlying the protective effects of EGb761 on melanocytes against oxidative stress has not been fully elucidated. In the present study, we found that EGb761 effectively protected melanocytes against oxidative stress‐induced apoptosis and alleviated the excessive accumulation of reactive oxygen species (ROS) and lipid peroxidation by enhancing the activity of antioxidative enzymes. Furthermore, the antioxidative effect of EGb761 was achieved by activating Nrf2 and its downstream antioxidative genes. In addition, interfering Nrf2 with siRNA abolished the protective effects of EGb761 on melanocytes against oxidative damage. In conclusion, our study proves that EGb761 could protect melanocytes from H₂O₂‐induced oxidative stress by activating Nrf2. Therefore, EGb761 is supposed to be a potential therapeutic agent for vitiligo.

Dynamic thiol/disulphide homeostasis in vitiligo patients

Introduction

Vitiligo is an acquired depigmentation disorder with melanocyte destruction.

Aim

To examine the thiol/disulphide balance in vitiligo patients and to compare the results with a healthy control group.

Material and methods

Thirty-two patients with vitiligo and 35 healthy individuals were included in the study. Native thiol, disulfide and total thiol levels in plasma were evaluated using a new and automated spectrophotometric method. Disulphide/total thiol, disulphide/native thiol and native thiol/total thiol levels were measured.

Results

There was no statistically significant difference between the two groups when the patient and control groups were compared in terms of thiol/disulphide balance (p > 0.05). There was no statistically significant difference in native thiol, disulphide and total thiol levels for vitiligo when compared with the control group (p > 0.005).

Conclusions

In recent years, there have been numerous studies on the role of oxidative stress in the etiopathogenesis of vitiligo. In this study, we investigated in vitiligo patients whether thiol/disulphide balance is a new oxidative stress marker. The results were compared with a healthy control group. We measured the thiol/disulphide balance by a new method developed by Erel and Neselioglu. The serum thiol/disulphide levels were similar in the vitiligo patients and the control subjects, which indicated that the thiol/disulphide balance was not affected by vitiligo. We are of the opinion that new investigations to determine serum levels of thiol/disulphide may shed light on the possible roles of these molecules in vitiligo.

Pigmentation Traits, Sun Exposure, and Risk of Incident Vitiligo in Women

Vitiligo is the most common cutaneous depigmentation disorder worldwide, yet little is known about specific risk factors for disease development. Using data from the Nurses' Health Study, a prospective cohort study of 51,337 white women, we examined the associations between (i) pigmentary traits and (ii) reactions to sun exposure and risk of incident vitiligo. Nurses' Health Study participants responded to a question about clinician-diagnosed vitiligo and year of diagnosis (2001 or before, 2002-2005, 2006-2009, 2010-2011, or 2012+). We used Cox proportional hazards regression models to estimate the multivariate-adjusted hazard ratios and 95% confidence intervals of incident vitiligo associated with exposures variables, adjusting for potential confounders. We documented 271 cases of incident vitiligo over 835,594 person-years. Vitiligo risk was higher in women who had at least one mole larger than 3 mm in diameter on their left arms (hazard ratio = 1.37, 95% confidence interval = 1.02-1.83). Additionally, vitiligo risk was higher among women with better tanning ability (hazard ratio = 2.59, 95% confidence interval = 1.21-5.54) and in women who experienced at least one blistering sunburn (hazard ratio = 2.17, 95% confidence interval = 1.15-4.10). In this study, upper extremity moles, a higher ability to achieve a tan, and history of a blistering sunburn were associated with a higher risk of developing vitiligo in a population of white women.

Glutathione Peroxidase Level in Patients with Vitiligo: A Meta-Analysis

Abnormality of glutathione peroxidase (GPx) is involved in the etiology and pathogenesis of vitiligo. However, the results were controversial. Aim. The purpose of this meta-analysis is to compare the levels of GPx between vitiligo patients and healthy controls. Methods. Relevant published articles were searched according to eligibility criteria. A meta-analysis was conducted to pool estimates of the standardized mean difference (SMD) with 95% confidence interval (CI). Results. Twenty-three studies with a total of 1076 vitiligo patients and 770 healthy controls were included. The pooled meta-analysis showed that patients with vitiligo had equivalent levels of GPx with the healthy controls (SMD = −0.47, 95% CI: −1.03 to 0.08, and p = 0.095). Further subgroup analysis showed that the GPx levels of Asian patients or segmental vitiligo patients were, respectively, lower than those of healthy controls (Asian: SMD = −0.47, 95% CI: −1.08 to 0.14, and p = 0.001; segmental: SMD = −3.59, 95% CI: −6.38 to −0.80, and p = 0.012). Furthermore, the GPx levels in serum/plasma were significantly decreased in either stable or active vitiligo patients, comparing to healthy controls (stable: SMD = −2.01, 95% CI: −3.52 to −0.49, and p = 0.009; active: SMD = −2.34, 95% CI: −4.07 to −0.61, and p = 0.008). Conclusion. This meta-analysis showed a significant association between low GPx level and vitiligo.

Serum Homocysteine and Total Antioxidant Status in Vitiligo: A Case Control Study in Indian Population

BACKGROUND

Oxidative stress is considered as an initial pathogenic event in melanocyte destruction. These free radicals are scavenged by antioxidants, whose sum of activity in serum is measured by total antioxidant status (TAS). In addition, homocysteine (Hcy) may mediate melanocyte destruction via increased oxidative damage. However, previous studies investigating these parameters in vitiligo provide equivocal results.

AIMS

To study and compare serum Hcy and TAS levels in vitiligo patients with controls and also to correlate these parameters with the various disease characteristics. The present study further looked into any correlation between serum Hcy and TAS in vitiligo.

MATERIALS AND METHODS

A case control study was conducted on 82 vitiligo patients and 83 controls aged 18-45 years after excluding factors which could potentially alter serum Hcy or TAS levels. Disease characteristics were studied and blood samples were obtained for measuring serum Hcy and TAS levels.

RESULTS

TAS levels were lower in vitiligo patients than controls (1.79 ± 0.51 vs. 2.16 ± 0.63 mmol/L; P < 0.001) and had a negative correlation with disease activity (r = -0.410, P < 0.001). However, serum Hcy levels were comparable between vitiligo patients (18.68 ± 9.90 μmol/L) and controls (20.21 ± 13.39 μmol/L) (P = 0.406). No significant correlation was found between serum Hcy and serum TAS levels.

CONCLUSIONS

Serum TAS may be further investigated to establish its role as biomarker for vitiligo since its levels also correlate with disease activity. However, serum Hcy may not be a reliable marker in Indian population probably because of differences in dietary habits.

Efficacy and Safety of 308-nm Monochromatic Excimer Lamp Versus Other Phototherapy Devices for Vitiligo: A Systematic Review with Meta-Analysis

BACKGROUND

Various phototherapy methods are used to treat vitiligo; however, the recent emergence of new devices has heightened debate concerning the best treatment method.

OBJECTIVE

We aimed to systematically review and meta-analyze published data comparing the efficacy and adverse effects of monochromatic excimer lamps versus excimer laser and narrowband ultraviolet B (NB-UVB) in treating vitiligo.

METHODS

A systematic search of PubMed, EMBASE, LILACS, Cochrane Central Register of Controlled Trials (CENTRAL), and clinical trials registries identified randomized controlled trials that included vitiligo patients, regardless of age, sex, or study language. We evaluated studies comparing excimer lamps with excimer laser or NB-UVB phototherapy.

RESULTS

The review included six studies (411 patients, 764 lesions). No study found significantly different efficacy between excimer lamps and excimer laser using the outcomes of ≥50% repigmentation [risk ratio (RR) = 0.97, 95% confidence interval (CI) 0.84-1.11] and ≥75% repigmentation (RR = 0.96, 95% CI 0.71-1.30). Likewise, no study found significant differences between excimer lamps and NB-UVB (RR = 1.14, 95% CI 0.88-1.48 for ≥50% repigmentation; RR = 1.81, 95% CI 0.11-29.52 for ≥75% repigmentation). Adverse effects were mild, including pruritus, burning sensation, and dryness, none of which interrupted treatment.

CONCLUSIONS

To our knowledge, this is the first systematic review of the efficacy and safety of excimer lamp treatment for vitiligo. Excimer lamps, excimer laser, and NB-UVB are all safe and effective in repigmentation of vitiligo lesions. Safety, effectiveness, and cost are considerations when choosing treatment.

PROSPERO REGISTRATION NUMBER

CRD42014015237.