The Impact of Antioxidants on Vitiligo and Melasma: A Scoping Review and Meta-Analysis

Abstract

Reactive oxygen species (ROS) generated during melanogenesis make melanocytes particularly vulnerable to oxidative stress, influencing their survival and melanin synthesis. Oxidative stress, significantly present in vitiligo and recently also detected in melasma, triggers inflammatory cascades and melanogenesis, making antioxidants a promising therapeutic avenue. A systematic search was conducted on Embase and Pubmed to study the efficacy of antioxidants for treating vitiligo and/or melasma. Meta-analysis was performed to assess the difference in Melasma Severity Index (MASI) scores between baseline and follow-up. Various antioxidants like polypodium leucotomos, ginkgo biloba, catalase/superoxide dismutase, and vitamin E have potential in vitiligo. For melasma, vitamin C, silymarin, and niacinamide were among those showing promise in reducing pigmentation, with vitamin C displaying significant effects in meta-analysis. Different antioxidants improve both vitiligo and melasma, with an increased minimal erythema dose (MED) following UV exposure being significant for vitiligo and tyrosinase inhibition being crucial for melasma. However, the efficacy of individual antioxidants varies, and their exact mechanisms, especially in stimulating melanocyte proliferation and anti-inflammatory pathways, require further investigation to understand better and optimize their use.

Recent Advances in Microneedling-Assisted Cosmetic Applications

“…Microneedling shows promise in treating melasma (hyperpigmentation) and vitiligo (hypopigmentation) to varying degrees with different mechanisms [25,87]. The skin's reaction to microneedling differs between melasma and vitiligo due to their distinct pathophysiology [90]. In melasma, microneedling may help by stimulating collagen production and facilitating the penetration of topical medications, potentially leading to improvement in hyperpigmented spots [86,87].…”

Silymarin Supplementation in Active Rheumatoid Arthritis: Outcomes of a Pilot Randomized Controlled Clinical Study

“…Fatigue was evaluated as mild, moderate, or severe depending on VAS scores (< 20, 20-50, and >50, respectively) [31,32]. Depression was assessed depending on BDI-II score as follows: no depression (0-13), mild to moderate depression (14)(15)(16)(17)(18)(19), moderate to severe depression (20)(21)(22)(23)(24)(25)(26)(27)(28), and severe depression (29-63) [28]. Anxiety level was indicated by GAD-7 score: minimal, mild, moderate, and severe anxiety for GAD-7 scores of 0-4, 5-9, 10-14, and 15-21, respectively [29].…”

“…Its main indications are viral- and toxin-induced hepatitis, alcoholic and non-alcoholic fatty liver disease, cirrhosis, Amanita mushroom poisoning, and hypercholesterolemia [ 10 , 11 , 12 ]. In addition, recent clinical studies have reported the efficacy of silymarin and/or silibinin in diabetes [ 13 ], cardiometabolic syndrome [ 14 ], Alzheimer’s disease [ 15 ], melasma [ 16 , 17 ], and as radioprotective agents [ 18 ]. Silymarin has a good safety profile, and no significant toxicity has been reported in human studies [ 11 ].…”