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.

Assessing the Oxidative State of the Skin by Combining Classical Tape Stripping with ORAC Assay

The antioxidant barrier system of the skin acts as the main defence against environmental pro-oxidants. Impaired skin oxidative state is linked to unhealthy conditions such as skin autoimmune diseases and cancer. Thus, the evaluation of the overall oxidative state of the skin plays a key role in further understanding and prevention of these disorders. This study aims to present a novel ex vivo model to evaluate the skin oxidative state by the measurement of its antioxidant capacity (AOC). For this the ORAC assay was combined with classical tape stripping and infrared densitometry to evaluate the oxidative state of the stratum corneum (SC). Outcomes implied the suitability of the used model to determine the intrinsic antioxidant capacity (iAOC) of the skin. The average iAOC of untreated skin was determined as 140 ± 7.4 µM TE. Skin exposure to UV light for 1 h reduced the iAOC by about 17%, and exposure for 2 h decreased the iAOC by about 30%. Treatment with ascorbic acid (AA) increased the iAOC in a dose-dependent manner and reached an almost two-fold iAOC when 20% AA solution was applied on the skin. The application of coenzyme Q10 resulted in an increase in the iAOC at low doses but decreased the iAOC when doses > 1% were applied on the skin. The results show that the combination of classical tape stripping and ORAC assay is a cost-effective and versatile method to evaluate the skin oxidative state and the pro-oxidate and antioxidative effects of topical skin treatments on the iAOC of the skin. Therefore, the model can be considered to be a valuable tool in skin research.

A Practical Approach to the Diagnosis and Treatment of Vitiligo in Children

Vitiligo is a common inflammatory skin disease with a worldwide prevalence of 0.5% to 2.0% of the population. In the pediatric population, the exact prevalence of vitiligo is unknown, although many studies state that most cases of vitiligo are acquired early in life. The disease is disfiguring, with a major psychological impact on children and their parents. Half of vitiligo cases have a childhood onset, needing thus a treatment approach that will minimize treatment side effects while avoiding psychological impacts. Management of vitiligo should take into account several factors, including extension, psychological impact, and possible associations with other autoimmune diseases. This review discusses the epidemiology of vitiligo and outlines the various clinical presentations associated with the disorder and their differential diagnosis. In addition, the pathophysiology and genetic determinants, the psychological impact of vitiligo, and management strategies are reviewed.

[Treatment of vitiligo]

The range of treatment options for vitiligo has significantly expanded in the last 10 years and we can offer our patients more effective treatment strategies supported by European guidelines and consensus findings. Topical and UV therapy are-often in combination-the main components of vitiligo treatment. The main outcome parameters include extent and maintenance of gained repigmentation, cessation of spreading, avoidance of side effects and the influence of the treatment on the quality of life. The efficacy of the currently available treatments is often limited. New options include antioxidative or melanocyte-stimulating adjuvant therapies in combination with UV or laser light as well as a topical maintenance treatment to reduce the risk of recurrences. In many cases, psychological support is indicated.