Does oxidative stress correlate with disease activity and severity in vitiligo? An analytical study

The efficacy of combined phototherapy with topical therapy in vitiligo: a network meta-analysis

BACKGROUND

The comparative effects of phototherapy and topical therapy in patients with vitiligo remain unclear. A network meta-analysis (NMA) was conducted to assess which combination therapy was more beneficial for patients with vitiligo.

METHODS

This study analyzed phototherapy, including narrowband ultraviolet B (NB-UVB) and 308-nm excimer laser/light (EL) combined with topical therapies. Randomized controlled trials were sourced from PubMed, Embase, and Cochrane Library. Data analysis was based on a random-effects model, and surface under the cumulative ranking (SUCRA) curves employed to assess the efficacy of the interventions.

RESULTS

This NMA included 27 trials, with a total of 2417 lesions (patches). According to the results of the SUCRA, for achieving ≥50% repigmentation, the top three combination therapies were phototherapy combined with antioxidants (SUCRA 87.7), corticosteroids (SUCRA 69.6), and calcineurin inhibitors (SUCRA 52.5), while for ≥75% repigmentation, the leading therapies were phototherapy combined with antioxidants (SUCRA 89.0), calcineurin inhibitors (SUCRA 70.3), and fractional CO2 laser (SUCRA 63.6).

CONCLUSIONS

This meta-analysis suggests that combining phototherapy with topical antioxidants, corticosteroids, or calcineurin inhibitors may offer superior outcomes for vitiligo patients. This study provides a reference for clinicians to develop personalized treatment plans for patients with vitiligo.

Galangin ameliorates PTU-induced vitiligo in zebrafish and B16F10 cells by increasing melanogenesis through activation of the p38/JNK MAPK pathway

Objective

Alpinia officinarum Hance is a traditional herb in Xinjiang for the treatment of vitiligo, and galangin (GA) is a flavonoid isolated from its roots. However, its therapeutic mechanism remains unclear.

Methods

In this study, 1-phenyl-2-thiourea (PTU) was used to establish a vitiligo model in zebrafish. After successful modeling, different concentrations of GA (1 and 2 μM) were administered, and the distribution of melanin granules was observed by assaying the melanin content, masson-fontana staining and tyrosinase activity. Transcriptomic analysis and molecular docking were used to identify potential GA-related pathways and targets for improving vitiligo. In addition, we evaluated the proliferation of B16F10 cells by PTU induction and also observed cellular melanin distribution using masson-fontana staining. Finally, Western blot was performed to detect the proteins of the relevant pathways.

Results

The results showed that GA significantly increased melanin production and tyrosinase activity in depigmented zebrafish. In addition, we found that GA decreased ROS and MDA levels and increased the expression of GSH, CAT and T-SOD. In addition, transcriptome analysis indicated that GA likely acts through the mitogen-activated protein kinase (MAPK) signaling pathway. GA has a strong binding affinity for important targets.GA significantly increased the expression of genes such as mapk8b, mapk14a, mapk3, mitf, tyr, tyrp1b, tyrp1a, dct, and oca2, and decreased the expression of genes such as expression of genes such as raf1 and egfr. In addition, GA enhanced the viability of B16F10 cells, increased intracellular melanin content, and increased the expression of proteins such as p38, JNK1/2/3, TYR, MITF, TRP1, TRP2, and so on.

Conclusion

GA increases melanin production and distribution, improves tyrosinase activity, upregulates the expression of related genes and proteins through activation of MAPK and tyrosine metabolic pathways, downregulates oxidative stress, and then regulates changes in melanin synthesis to improve vitiligo.

Markers of Metabolic Abnormalities in Vitiligo Patients

While vitiligo is primarily caused by melanocyte deficiency or dysfunction, recent studies have revealed a notable prevalence of metabolic syndrome (MetS) among patients with vitiligo. This suggests shared pathogenic features between the two conditions. Individuals with vitiligo often exhibit variations in triglyceride levels, cholesterol, and blood pressure, which are also affected in MetS. Given the similarities in their underlying mechanisms, genetic factors, pro-inflammatory signalling pathways, and increased oxidative stress, this study aims to highlight the common traits between vitiligo and metabolic systemic disorders. Serum analyses confirmed increased low-density lipoprotein (LDL) levels in patients with vitiligo, compared to physiological values. In addition, we reported significant decreases in folate and vitamin D (Vit D) levels. Oxidative stress is one of the underlying causes of the development of metabolic syndromes and is related to the advancement of skin diseases. This study found high levels of inflammatory cytokines, such as interleukin-6 (IL-6) and chemokine 10 (CXCL10), which are markers of inflammation and disease progression. The accumulation of insulin growth factor binding proteins 5 (IGFBP5) and advanced glycation end products (AGEs) entailed in atherosclerosis and diabetes onset, respectively, were also disclosed in vitiligo. In addition, the blood-associated activity of the antioxidant enzymes catalase (Cat) and superoxide dismutase (SOD) was impaired. Moreover, the plasma fatty acid (FAs) profile analysis showed an alteration in composition and specific estimated activities of FAs biosynthetic enzymes resembling MetS development, resulting in an imbalance towards pro-inflammatory n6-series FAs. These results revealed a systemic metabolic alteration in vitiligo patients that could be considered a new target for developing a more effective therapeutic approach.

Oxidative Stress and Potential Antioxidant Therapies in Vitiligo: A Narrative Review

Vitiligo is a chronic skin disorder characterised by the loss of melanocytes and subsequent skin depigmentation. Although many theories have been proposed in the literature, none alone explains the pathogenesis of vitiligo. Oxidative stress has been identified as a potential factor in the pathogenesis of vitiligo. A growing body of evidence suggests that antioxidant therapies may offer a promising approach to managing this condition. This review summarises the potential mechanisms of oxidative stress and the types of melanocyte death in vitiligo. We also provide a brief overview of the most commonly studied antioxidants. Melanocytes in vitiligo are thought to be damaged by an accumulation of reactive oxygen species to destroy the structural and functional integrity of their DNA, lipids, and proteins. Various causes, including exogenous and endogenous stress factors, an imbalance between prooxidants and antioxidants, disruption of antioxidant pathways, and gene polymorphisms, lead to the overproduction of reactive oxygen species. Although necroptosis, pyroptosis, ferroptosis, and oxeiptosis are newer types of cell death that may contribute to the pathophysiology of vitiligo, apoptosis remains the most studied cell death mechanism in vitiligo. According to studies, vitamin E helps to treat lipid peroxidation of the skin caused by psoralen ultra-violet A treatment. In addition, Polypodium leucotomos increased the efficacy of psoralen ultra-violet A or narrow-band ultraviolet B therapy. Our review provides valuable insights into the potential role of oxidative stress in pathogenesis and antioxidant-based supporting therapies in treating vitiligo, offering a promising avenue for further research and the development of effective treatment strategies.

Enhanced Natural Strength: Lamiaceae Essential Oils and Nanotechnology in In Vitro and In Vivo Medical Research

The Lamiaceae is one of the most important families in the production of essential oils known to have a wide spectrum of biological activity. Recent research has highlighted the dermatological capabilities of various Lamiaceae essential oils, which appear to offer potential in free radical scavenging and anti-inflammatory activity. Some have also been extensively studied for their tissue remodeling and wound-healing, anti-aging, anti-melanogenic, and anti-cancer properties. Certain Lamiaceae essential oils are promising as novel therapeutic alternatives for skin disorders. This potential has seen substantial efforts dedicated to the development of modern formulations based on nanotechnology, enabling the topical application of various Lamiaceae essential oils. This review provides a comprehensive summary of the utilization of various essential oils from the Lamiaceae family over the past decade. It offers an overview of the current state of knowledge concerning the use of these oils as antioxidants, anti-inflammatory agents, wound-healers, anti-aging agents, anti-melanogenic agents, and anticancer agents, both alone and in combination with nanoparticles. Additionally, the review explores their potential applicability in patents regarding skin diseases.

JAK inhibitors in vitiligo: what they hit and what they miss - an immunopathogenesis based exposition of existing evidence

INTRODUCTION

Vitiligo is an autoimmune disorder which presents as depigmented macules due to selective loss of melanocytes. Heightened expression of Janus Kinase Signal transducers and activators of transcription (JAK STAT) pathway, which mediate cytokines action, suggest that targeting this signaling pathway may be an effective option.

AREAS COVERED

A PubMed search was carried out with the broad key words 'JAK,' 'vitiligo' from 2016 to 2023. We also analyzed papers where tissue-based JAK expression was studied, with or without concomitant treatment with JAK inhibitors. We address the role of JAK inhibitors in vitiligo and their effect on repigmentation of lesions.

EXPERT OPINION

While JAK inhibitors help in cessation of disease progression, they have no in vivo action on melanocyte proliferation and hence cannot result in re-pigmentation as a monotherapy. There is a need for tissue-based JAK and cytokine-based studies with post-treatment expression data to validate the role of this class of drugs in vitiligo. There is as yet no data to suggest that selective JAK inhibitors are superior to pan JAK inhibitors for vitiligo. JAK inhibitors are useful in active disease and effectively modulate the cytokine mediated autoimmune dammage and makes them singularly superior to oral glucocorticosteroids.

Vitiligo: An immune disease and its emerging mesenchymal stem cell therapy paradigm

Melanocyte damage, innate immune response, adaptive immune response, and immune inflammatory microenvironment disorders are involved in the development of the immunological pathogenic mechanism of vitiligo. Mesenchymal stem cells are considered an ideal type of cells for the treatment of vitiligo owing to their low immunogenicity, lower rates of transplant rejection, and ability to secrete numerous growth factors, exosomes, and cytokines in vivo. The regulation of signaling pathways related to oxidative stress and immune imbalance in the immunological pathogenesis of vitiligo can improve the immune microenvironment of tissue injury sites. In addition, co-transplantation with melanocytes can reverse the progression of vitiligo. Therefore, continuous in-depth research on the immunopathogenic mechanism involved in this disease and mesenchymal stem cell-based therapy is warranted for the treatment of vitiligo in the future.

Damage-associated molecular patterns in vitiligo: igniter fuse from oxidative stress to melanocyte loss

OBJECTIVES

The pathogenesis of vitiligo remains unclear. In this review, we comprehensively describe the role of damage associated molecular patterns (DAMPs) during vitiligo pathogenesis.

METHODS

Published papers on vitiligo, oxidative stress and DAMPs were collected and reviewed via database searching on PubMed, MEDLINE and Embase, etc.

RESULTS

Oxidative stress may be an important inducer of vitiligo. At high oxidative stress levels, damage-associated molecular patterns (DAMPs) are released from keratinocytes or melanocytes in the skin and induce downstream immune responses during vitiligo. Treatment regimens targeting DAMPs can effectively improve disease severity.

DISCUSSION

DAMPs play key roles in initiating host defenses against danger signals, deteriorating the condition of vitiligo. DAMP levels in serum and skin may be used as biomarkers to indicate vitiligo activity and prognosis. Targeted therapies, incorporating HMGB1, Hsp70, and IL-15 could significantly improve disease etiology. Thus, novel strategies could be identified for vitiligo treatment by targeting DAMPs.

The Role of Oxidative Stress in Atopic Dermatitis and Chronic Urticaria

Atopic dermatitis (AD) and chronic urticaria (CU) are common skin diseases with an increasing prevalence and pathogenesis that are not fully understood. Emerging evidence suggests that oxidative stress plays a role in AD and CU. The aim of the single-center cross-sectional study was to compare markers of oxidative stress in 21 patients with AD, and 19 CU patients. The products of protein oxidation, total antioxidant capacity (TAC), and markers of lipid peroxidation were estimated in the serum. AD patients had a higher level of advanced protein oxidation products and a lower level of thiol groups than healthy participants. However, CU patients had statistically higher levels of AOPP and 3-nitrotyrosine than healthy subjects. The level of thiol groups and serum TAC decreased significantly in patients with CU. There was no difference in serum concentration of lipid peroxidation products, Amadori products, ratio of reduced to oxidized glutathione, and ability of albumin to binding cobalt between AD or CU patients compared to healthy subjects. We found a moderate positive significant correlation between AOPP and age in patients with AD. In patients with CU, TAC was negatively correlated with age. These results may shed light on the etiopathogenesis of AD or CU, and confirm an oxidative burden in these patients. Furthermore, our study could be useful in developing new therapeutic methods that include using antioxidants in dermatological diseases.

Thiol-Disulfide Homeostasis in Skin Diseases

Oxidative stress represents the imbalance between oxidants and antioxidants and has been associated with a wide range of diseases. Thiols are the most important compounds in antioxidant defense. There is an equilibrium between thiols and their oxidized forms, disulfides, known as dynamic thiol-disulfide homeostasis (TDH). In 2014, Erel and Neselioglu developed a novel automated assay to measure thiol and disulfide levels. Subsequently, many researchers have used this simple, inexpensive and fast method for evaluating TDH in various disorders. We have reviewed the literature on the role of TDH in skin diseases. We identified 26 studies that evaluated TDH in inflammatory diseases (psoriasis, seborrheic dermatitis, atopic dermatitis, vitiligo, acne vulgaris and rosacea), allergic diseases (acute and chronic urticaria) and infectious diseases (warts, pityriasis rosea and tinea versicolor). The results are heterogeneous, but in most cases indicate changes in TDH that shifted toward disulfides or toward thiols, depending on the extent of oxidative damage.

Genetic variants affecting chemical mediated skin immunotoxicity

The skin is an immune-competent organ and this function may be impaired by exposure to chemicals, which may ultimately result in immune-mediated dermal disorders. Interindividual variability to chemical-induced skin immune reactions is associated with intrinsic individual characteristics and their genomes. In the last 30-40 years, several genes influencing susceptibility to skin immune reactions were identified. The aim of this review is to provide information regarding common genetic variations affecting skin immunotoxicity. The polymorphisms selected for this review are related to xenobiotic-metabolizing enzymes (CYPA1 and CYPB1 genes), antioxidant defense (GSTM1, GSTT1, and GSTP1 genes), aryl hydrocarbon receptor signaling pathway (AHR and ARNT genes), skin barrier function transepidermal water loss (FLG, CASP14, and SPINK5 genes), inflammation (TNF, IL10, IL6, IL18, IL31, and TSLP genes), major histocompatibility complex (MHC) and neuroendocrine system peptides (CALCA, TRPV1, ACE genes). These genes present variants associated with skin immune responses and diseases, as well as variants associated with protecting skin immune homeostasis following chemical exposure. The molecular and association studies focusing on these genetic variants may elucidate their functional consequences and contribution in the susceptibility to skin immunotoxicity. Providing information on how genetic variations affect the skin immune system may reduce uncertainties in estimating chemical hazards/risks for human health in the future.

Germacrone alleviates okadaic acid-induced neurotoxicity in PC12 cells via M1 muscarinic receptor-mediated Galphaq (Gq)/phospholipase C beta (PLCβ)/ protein kinase C (PKC) signaling

Alzheimer’s disease (AD) is a neurodegenerative disorder with prominent individual morbidity and mortality among elderly people. Germacrone (Germ) has been reported to exert dominant protective roles in multiple human diseases, and neurological diseases are also included. The intention of this paper is to determine the impacts of Germ on okadaic acid (OA)-treated PC12 cells and confirm the hidden regulatory mechanism. First, PC12 cells were induced by OA in the absence or presence of Germ. Cell counting kit-8 assay was to monitor cell proliferation. Western blot was to test the protein levels of cholinergic muscarinic M1 receptor (CHRM1), Galphaq (Gq), phospholipase C beta (PLCβ) and protein kinase C (PKC). The levels of reactive oxygen species (ROS) and other oxidative stress markers were evaluated using corresponding kits. ELISA was used to estimate the levels of AD markers. RT-qPCR was used to examine the mRNA levels of beta-site amyloid-precursor-protein-cleaving enzyme 1 (BACE-1) and apolipoprotein E (APOE). The results uncovered that Germ enhanced the proliferation of OA-insulted PC12 cells, elevated the protein level of CHRM1 and activated the Gq/PLCβ/PKC signaling. Moreover, after OA-induced PC12 cells were administered with Germ, insufficiency of CHRM1 impeded cell proliferation, enhanced oxidative stress and neuron injury and inactivated the Gq/PLCβ/PKC signaling. Furthermore, the addition of Gq inhibitor UBO-QIC, PLCβ inhibitor U73122 or PKC inhibitor Go6983 reversed the enhanced proliferation, the reduced oxidative stress and neuron injury in OA-treated PC12 cells caused by Germ. Collectively, Germ modulated M1 muscarinic receptor-mediated Gq/PLCβ/PKC signaling, thereby alleviating OA-induced PC12 cell injury.

Role of nutritional supplements in selected dermatological disorders: A review

BACKGROUND

While a plethora of literature continues to be published on the role of nutritional agents both in lay press and indexed journals, the data is not on a firm footing and leaves the dermatologist in a quandry and the patient confused. The various agents include vitamins, minerals, amino acids, antioxidants, diets & gluten. A proper knowledge of the role of nutritional supplements in dermatological diseases can be a useful tool in advising the patients and in certain cases ameliorating the disorder.

PATIENTS/METHODS

Literature review of last 15 years was made using the terms "diet in dermatology," "nutrition and skin," "nutritional supplements in dermatology," "nutritional agents and acne," "nutritional agents and alopecia," and "nutritional agents and psoriasis."

RESULTS

While there are multiple publications on the use of nutritional supplements for amelioration of skin diseases, most of them are based on either associations or in vitro studies, but very few transcend the rigors of a clinical trial or the holey grail of a double-blinded randomized controlled trial. There seem to be some evidence in acne, psoriasis, telogen effluvium, urticaria & vitiligo. Coeliac disease and dermatitis herpetiformis have a strong link with diet. Rosacea has a strong link with certain foods, but the other disorders like melasma, aphthous stomatitis do not have any scientifically validated association with diet.

CONCLUSIONS

Our updated review examines the role of nutritional supplements and antioxidants in various dermatological disorders. We have found that there are varying levels of evidence with notable associations of low glycemic diet & acne, fish oil & weight loss with psoriasis, fish oils & probiotics with atopic dermatitis & vitamins & botanical extracts with vitiligo. The evidence for diet and nutrition in bullous disorders and photoageing is scarce. The role of low histamine diet in urticaria is useful in select cases of episodic urticaria. Rosacea is triggered by hot and spicy food . Apart from gluten and Dermatitis Herpetiformis, no diet can be considered disease modifying in our reveiw. The lack of comparison of nutritional or dietary modiffication with conventional validated agents, makes the data difficult to translate in real world patient management.

Oral gliadin-protected superoxide dismutase in addition to phototherapy for treating non-segmental vitiligo: A 24-week prospective randomized placebo-controlled study

Background

Despite a solid rationale, the usefulness of antioxidants in treating vitiligo has not been clearly demonstrated. Combining superoxide dismutase (SOD) with a wheat gliadin biopolymer protects it during the passage through the gastrointestinal tract.

Objective

To evaluate the efficacy of gliadin‐protected SOD (GP‐SOD), associated with narrowband ultraviolet B(NB‐UVB), for treating vitiligo.

Methods

We conducted a 24‐week monocentric interventional prospective randomized placebo‐controlled trial in the tertiary center for vitiligo care in the department of Dermatology of Nice University hospital, Nice, France.

Subjects with non‐segmental vitiligo affecting more than 5% of the total body surface were included. The subjects received gliadin‐protected SOD (GP‐SOD; 1 g/day for 12 weeks followed by 0.5 g/day for 12 weeks) or placebo in combination with twice‐weekly sessions of NB‐UVB. The primary endpoint was the total repigmentation rate at 24 weeks, compared with baseline, as assessed by investigator‐assessed Vitiligo Extent Score (VES) on standardized pictures.

Results

A total of 50 patients were included. After 24 weeks, a greater improvement in VES was observed in the GP‐SOD group (19.85%; SE 4.63, P < 0.0001) compared with the placebo group (8.83%; SE 4.72, P = 0.0676). Tolerance was good in both groups. No related side‐effect was reported.

Conclusions

The use of GP‐SOD appears to be a useful add‐on to phototherapy in the treatment of vitiligo patients.

Novel immunological and genetic factors associated with vitiligo: A review

Vitiligo is a skin disorder characterized by depigmentation of the skin due to a lack of melanin. This condition affects men and woman of all ages and its incidence is not restricted by ethnicity or region. Vitiligo is a multifactorial disease, in which melanocytes, which serve important functions in skin pigmentation and immune processes, are impaired. There is sufficient evidence that immunological and genetic factors are primarily responsible for the destruction and dysfunction of melanocytes. Therefore, genetic DNA sequence variants that participate in skin homeostasis, pigmentation and immune response regulation, as well as altered expression patterns, may contribute to the risk of developing vitiligo. The current review presented an overview of the mechanism of pigmentation and of currently known factors involved in depigmentation, as well as the classification, epidemiology, associated comorbidities, risk factors, immunopathogenesis and several genetic and molecular changes associated with vitiligo.