Disorders of hyperpigmentation. Part II. Review of management and treatment options for hyperpigmentation

Australian Sunscreens: The Price of Protection for Skin of Colour With Pigmentary Disorders

Australia experiences some of the highest ultraviolet radiation (UVR) levels globally, known for causing sunburn, skin cancers, photoageing and immunosuppression. While effects of UVA and UVB are well-studied, visible light (VL; 400-700 nm) is the driving force behind pigmentary disorders, especially in skin of colour (SOC) patients. Nearly 50% of Australians are affected, with significant impacts on appearance and psychological well-being. Tinted sunscreens containing iron oxides and pigmentary-grade titanium dioxide are the only effective options for blocking VL. However, Australia's stringent Therapeutic Goods Administration (TGA) regulations limit the availability of colour-matched tinted sunscreens, significantly impacting SOC patients. SOC patients may also underestimate their need for photoprotection, believing their skin provides sufficient natural protection. In dermatological practice, tailored sunscreen recommendations for darker skin tones may sometimes be overlooked. This review explores the barriers to effective treatment and the cost implications for SOC individuals suffering from pigmentary disorders in Australia. The goal is to guide both patients and dermatologists in making informed decisions on VL protection and skin tone matching.

Botulinum neurotoxin type DC (BoNT/DC) cleavage of VAMP3 reduces melanin production in melanocytes

Melanin in skin and hair protects cells from UV damage; however, uneven skin color or hyperpigmentation is a common aesthetic concern. Melanin is synthesized in melanosomes, organelles within melanocytes, where tyrosinase converts tyrosine to melanin. Trafficking of tyrosinase or other cargo (eg, premelanosome protein [PMEL]) may depend on vesicle-associated membrane proteins (VAMPs); interfering with VAMPs has been reported to impact melanogenesis. Botulinum neurotoxin type DC (BoNT/DC) is a naturally occurring mosaic serotype that cleaves the SNARE proteins VAMP1-3. This study evaluated BoNT/DC as a potential treatment for hyperpigmentation by testing if it affects melanogenesis. In melanocytes, BoNT/DC cleaved VAMP2 and VAMP3, and knockdown of VAMP3, but not VAMP2, reduced melanin content, which suggests that BoNT/DC may affect melanogenesis via VAMP3 cleavage. Indeed, BoNT/DC (5 nM) produced a ∼50 % reduction in melanin content in melanocytes, and in 2 human melanocyte models, BoNT/DC, but not BoNT/A, significantly reduced melanin content (∼40-50 %) without cytotoxicity. Electron microscopy showed that BoNT/DC-treated melanocytes contained more early-stage (II) and fewer late-stage (IV) melanosomes than vehicle- or BoNT/A-treated melanocytes. Overall, BoNT/DC reduced melanin content in multiple melanocyte models, and its lightening effects are likely due to VAMP3 cleavage interfering with trafficking of cargo (eg, tyrosinase, PMEL) required for melanogenesis.

Acne-induced Post-inflammatory Hyperpigmentation: From Grading to Treatment

Acne-induced post-inflammatory hyperpigmentation (AI-PIH) can occur without any visible clinical evidence of significant inflammation, even in patients with mild to moderate acne. Currently, visual assessment is the main criterion for evaluating the severity of PIH, including that of AI-PIH in daily clinical practice. Treatment indications are lacking. This work provides an easy-to-use AI-PIH severity grading tool for daily clinical practice as well as indications on how to prevent and treat AI-PIH using currently available treatment options. Five experts in acne provided a short overview concerning the epidemiology and physiopathology of AI-PIH, developed an AI-PIH severity grading tool, and proposed preventive measures as well as an AI-PIH treatment algorithm. Only a small number of epidemiological data on AI-PIH are available, confirming that the condition is mainly observed in patients with Phototypes IV to VI. The physiopathology of AI-PIH is still not completely understood. Innate immunity, Cutibacterium acnes, and external factors such as UV radiation, visible light, and air pollution play a role in its development. An easy-to-use AI-PIH severity grading tool (Acne PIgmentation Grading) allows quick assessment of acne severity during the consultation, and, in addition to proposed preventive measures, a treatment algorithm is proposed according to AI-PH severity. Patient education remains key. Providing an AI-PIH severity assessment tool as well as preventive and treatment recommendations may help to manage AI-PIH more efficiently.

The Therapeutic and Preventive Effects of Light-Emitting Diode (LED) for Post-Inflammatory Erythema and Hyperpigmentation: A Pilot Study

Background/Purpose Photobiomodulation (PBM) using light-emitting diodes (LEDs) benefits tissue regeneration and wound healing. However, evidence regarding the efficacy of LED for post-inflammatory erythema (PIE) and post-inflammatory hyperpigmentation (PIH) is limited. The aim of this study was to explore the effect of medical LED (830 nm and 590 nm) in the prevention and treatment of PIE and PIH. Methods The in vivo PIE/PIH model was simplified to erythema and pigmentation reaction after acute UVB exposure. 308 nm LED light (225 or 270 mJ/cm2) was induced in vivo in the PIE/PIH model on the thigh of ten healthy subjects. Every subject received therapeutic and preventive irradiation (n = 10 in each group). 830 nm (60 J/cm2) and 590 nm LEDs (20 J/cm2) were irradiated, respectively. For therapeutic irradiation, the PIE/PIH model was induced on D1, and LEDs were irradiated on D0, 1, 3, 6 and 8. For preventive irradiation, LEDs were irradiated on D0, 1, 3, 6, and 8 and the PIE/PIH model was induced on D9. Erythema index (EI), melanin index (MI), transdermal water loss (TEWL), and C-Cube photography were measured during 10-day follow-up visits. Results For therapeutic irradiation, ΔEI and ΔMI in the 830 nm treatment group were significantly lower than in the control group (ΔEI: 9.30 vs. 11.52, p = 0.027; ΔMI: 7.79 vs. 9.25, p = 0.026). No significant difference was found between the 590 nm treatment group and the control group in ΔEI or ∆MI (p > 0.05). For preventive irradiation, ΔEI in the 830 nm prevention group and the 590 nm prevention group were both significantly lower than the control group (830 nm: 9.85 vs. 19.90, p = 0.001; 590 nm: 12.50 vs. 19.90, p = 0.008). No significant difference was found between the two prevention LED groups (p > 0.05). Conclusions Both 830 nm and 590 nm LEDs showed preventive effects for PIE, and 830 nm LEDs could effectively improve PIE and PIH.

Concurrent management of vitiligo and acquired disorders of hyperpigmentation: a comprehensive literature review and current practice gaps

Few studies discuss the co-management of vitiligo and acquired hyperpigmentation disorders (AHD) such as melasma, erythema dyschromicum perstans, post-inflammatory hyperpigmentation, drug-induced hyperpigmentation, and lichen planus pigmentosus. This review discusses clinical studies examining co-management strategies and identifies current practice gaps. Dermatology Life Quality Index scores are higher in individuals with vitiligo or melasma. It is plausible that populations experiencing both conditions may exhibit worsened psychological outcomes because of stigmas and perceived social beauty standards. Standard treatments for vitiligo aim to increase pigmentation, while AHD treatments target decreasing pigmentation, causing potential worsening of contrast between multiple skin tones for patients experiencing both disorders. Tretinoin may prevent narrowband ultraviolet B (NBUVB)-induced hyperpigmentation in patients with vitiligo without altering treatment response and is also beneficial for managing AHD. In addition, the use of oral tranexamic acid to treat melasma does not diminish the response to NBUVB phototherapy. Platelet-rich plasma (PRP) injections and oral Polypodium leucotomos extract may also be beneficial for comanaging vitiligo and AHD. However, practice guidelines are needed to optimize care for this patient population.

Evaluation of the Efficacy of a Serum Containing Niacinamide, Tranexamic Acid, Vitamin C, and Hydroxy Acid Compared to 4% Hydroquinone in the Management of Melasma

INTRODUCTION

Melasma is a common skin condition that remains challenging to treat. Hydroquinone at 4% (HQ4%) is a frequently prescribed depigmenting compound that has been associated with potential side effects.

OBJECTIVE

This study assessed the benefit in melasma of an anti-hyperpigmentation serum (Serum B3 containing 5% niacinamide, 1% tranexamic acid, 0.2% of a stabilized form of vitamin C, and different hydroxy acids) compared to HQ4%.

MATERIALS AND METHODS

In a single-site, investigator-blind, randomized study, 60 females aged between 20 and 50 years with facial melasma received Serum B3 for 5 months (Group 1) or HQ4% for 3 months followed by Serum B3 for an additional2 months (Group 2). Endpoints were Melasma Area and Severity Index (MASI), modified MASI (mMASI), Investigational Global Assessment, erythema, clinical cutaneous parameters, and safety. Subjects assessed quality of life (QoL) and cosmetic acceptability. Confocal reflecting microscopy was performed.

RESULTS

A significant (p < 0.001) reduction in pigmentation was seen in both groups after 3 months. A higher erythema score was noted in Group 2. Hydration and skin barrier function performed better in Group 1. QoL significantly (p < 0.001) improved in both groups after 84 days. Serum B3 was tolerated better than HQ, and subjects appreciated Serum B3. Melanin density reduction was similar for both groups after 3 and 5 months.

CONCLUSION

Serum B3 used for 5 months and HQ4% applied for 3 months, followed by a 2-month use of Serum B3, had a similar efficacy profile, with Serum B3 having a better local tolerance and patient acceptability.

Small-Molecule Tyrosinase Inhibitors for Treatment of Hyperpigmentation

Increasing attention is being focused on skin health currently, especially the excessive deposition of melanin in the skin. Tyrosinase, the rate-limiting enzyme in melanin biosynthesis, is a crucial enzyme in melanin synthesis. However, existing tyrosinase inhibitors pose some degree of toxicity to humans. Therefore, the development of more efficient and low-toxicity tyrosinase inhibitors is urgently needed. This review briefly depicts the melanin biosynthesis process and the crystal structure and catalytic mechanism of tyrosinase. The latest research progress regarding small-molecule tyrosinase inhibitors is also reviewed. Moreover, the structure-function relationships are analyzed and summarized. This is expected to provide new and more scientific insights to enable researchers to explore safer and more potent tyrosinase inhibitors.

Lotus Sprout Extract Induces Selective Melanosomal Autophagy and Reduces Pigmentation

BACKGROUND

Hyperpigmentation disorders are caused by the excess production and irregular accumulation of melanin. Existing treatments often have limited efficacy and adverse effects, necessitating the development of new skin-brightening agents. Lotus sprout extract (LSE) was identified as a potential pigment-correcting agent. However, the active compounds responsible for driving mechanisms related to this activity remain unknown.

AIMS

This study aimed to investigate the effects of LSE and its active components, neferine and liensinine, on melanin accumulation and to understand how LSE reduces skin pigmentation.

METHODS

Melanin accumulation was analyzed in MNT-1 human melanoma cells and MelanoDerm human skin equivalents following neferine, liensinine, or LSE treatment. The effects of the compounds on different pathways regulating melanin levels were evaluated by gene expression, biochemical assays, and western blotting. Melanosome ultrastructure was monitored using transmission electron microscopy (TEM).

RESULTS

Neferine and liensinine reduced melanin accumulation in MNT-1 cells without downregulating melanogenesis-related genes or inhibiting tyrosinase activity. Instead, these compounds increased autophagic flux, suggesting that the reduction in pigmentation was due to increased melanin degradation. LSE also reduced melanin accumulation and activated autophagy in normal human melanocytes and MelanoDerm tissue. Autophagosomes induced by LSE treatment contained only melanosomes, and structural changes in melanosomes suggested that LSE may disrupt melanosome maturation.

CONCLUSION

This study revealed a novel mechanism for LSE, neferine, and liensinine in reducing pigmentation, potentially through the induction of autophagy and subsequent melanosome degradation. These findings suggest that LSE and its enriched bioactive compounds could be promising agents for treating hyperpigmentation.

Innovations in Hyperpigmentation

Photoprotection remains the foundation of treatment for all dyschromias and cosmetic camouflage as it provides concealment of pigmentation until therapeutic agents are effective. Innovations in the treatment of dyschromias encompass topical, systemic, and procedural modalities.

Research situation, hot spots, and global trends of melasma therapy: Bibliometric insights and visual analysis from 2000 to 2023

BACKGROUND

Melasma is a prevalent pigmented disease, yet its pathogenesis remains unclear, posing challenges for effective treatment. Bibliometric analysis, a novel approach to literature research, offers the opportunity to evaluate research trends through qualitative and quantitative methods. This study utilizes bibliometric methods to analyze the existing literature on melasma treatment, examining influential publications, institutions, countries, and authors through statistical analysis.

METHODS

In order to retrieve manuscripts related to the topic of melasma treatment, we conducted a search using the search formula: (TS = (melasma or Chloasma or "mask of pregnancy")) AND TS = (treatment or therapy). We searched through the Web of Science Core Collection database, covering publications from 2000 to 2023. VOSviewer, CiteSpace and the Bibliometric online site (https://bibliometric.com/app) were used to conduct this bibliometric analysis. Our analysis focused on various factors including publications, authors co-authorship, institutions, countries, citation analysis, keywords co-occurrence, references co-citation and journal co-citation.

RESULTS

A total of 943 articles and 200 reviews were published between 2000 and 2023, accumulating a total of 8628 citations. The average number of citations per item was 18.85, and the average number of citations per year was 292.69. The most prolific author, Sungeun Chang, contributed a total of 9 articles. Cario University emerged as the top research institution. The United States led in terms of article publications with a count of 276. In the past 5 years, the research trends in this field have primarily focused on tranexamic acid and epidermal melasma, as indicated by the burst analysis of publications and keywords.

CONCLUSIONS

The United States continues to lead in terms of institutions and research output. The current emphasis is on the meticulous implementation of tranexamic acid and laser therapy. It is crucial to foster enhanced collaboration among countries, institutions, and authors to facilitate improved research.

A review of therapies for hyperpigmentation modulating the synthesis of eumelanin to pheomelanin

There are significant psychosocial burdens in patients with hyperpigmentation, which emphasizes the importance of treatment. Current gold standard for treatment is hydroquinone; however, alternatives have been developed given the concern for side effects of hydroquinone. Melanogenesis is responsible for the production of eumelanin and pheomelanin; there are many factors that will determine whether eumelanin or pheomelanin will be produced. Eumelanin is known for its photoprotective qualities, while pheomelanin is implicated in photocarcinogenesis and photoaging. Multiple treatment modalities for hyperpigmentation that shift eumelanin to pheomelanin synthesis exist. Cysteamine, glutathione, kojic acid, and methyl sulfonyl methane are four agents used to treat hyperpigmentation by shifting the production of eumelanin to pheomelanin. It is critical to discuss photoprotection with patients to help reduce the potential impact of increased pheomelanin production and to expand research in this area.

Mechanism of the wine pomace tannin in hyperpigmentation inhibition: Impact on signaling pathways, cell proliferation, and tyrosinase activity

After winemaking, tannins with high polymerization remain in the pomace. Utilizing these tannin fractions is a concern for the wine industry. While tannins show potential in treating hyperpigmentation, their mechanisms in vivo and at the cellular level are unclear. Herein, pomace tannin fractions (PTFs) were isolated post-winemaking. Nuclear magnetic resonance spectroscopy and mass spectrometry analysis showed PTFs were composed of (epi)catechin gallate and (epi)catechin as terminal and extensional units, with polymerization degrees of 10, 16, and 35. In vivo studies demonstrated that PTFs removed ∼76 % of skin melanin, comparable to hydroquinone. The inhibition by PTFs is due to: (1) Inhibition of the Wnt and melanogenesis pathways, downregulating key melanin synthesis proteins (TYR, TYRP1, TYRP2); (2) Inducing cell cycle arrest at the G1/S checkpoint, disrupting DNA, decreasing mitochondrial membrane potential and integrity, and slowing melanocyte proliferation; (3) Superior tyrosinase inhibitory activity by binding to tyrosinase, chelating copper ions, and demonstrating antioxidant properties. These findings suggest that PTFs inhibit melanin synthesis by the combination of the above mentioned ways, supporting the medical use of winemaking tannins.

Photobiomodulation Using 830 nm Lighting-Emitting Diode Inhibits Melanogenesis via FOXO3a in Human Melanocyte

Photobiomodulation (PBM) using 830 nm light-emitting diode (LED) benefits tissue regeneration, wound healing and neural stimulation. However, there is not much exploration of its effect on melanocytes and ex vivo skin model. This study aims to investigate the mechanism behind the anti-melanogenic activity of 830 nm LED and provides evidence for its activity in human ex vivo skin model. Our results showed that 830 nm LED at fluences ranging from 5 to 20 J/cm2 inhibited melanosome maturation and reduced melanin content, tyrosinase activity and melanogenesis-related proteins. 830 nm LED inhibited the phosphorylation of AKT and its downstream FOXO3a, leading to nuclear translocation of FOXO3a. Furthermore, FOXO3a knockdown and AKT activator like SC79 could reverse the melanogenesis inhibition phenotype induced by 830 nm LED. In human ex vivo skin model, Fontana-Masson staining revealed a decrease in epidermal basal pigmentation after 830 nm LED irradiation. Taken together, 830 nm LED demonstrated the anti-melanogenic activity via FOXO3a.

The amino acid transporter SLC16A10 promotes melanogenesis by facilitating the transportation of phenylalanine

Phenylalanine is a crucial amino acid in the process of melanogenesis. However, the exact mechanism by which it is transported into melanocytes has not been disclosed. The aim of this study was to identify and examine the key transporters that are responsible for phenylalanine transportation and evaluate their significance in melanogenesis. The amino acid transporter SLC16A10 was found to be up-regulated in both melasma (GSE72140) and sun-exposed skin (GSE67098). The protein levels of SLC16A10 were proportional to the melanin content in melanocytic nevi, indicating that SLC16A10 was related to melanogenesis. After SLC16A10 overexpression, melanin increased significantly in MNT1 cells. Meanwhile, the expression of melanogenesis-related proteins such as TYR and TYRP1 increased, while their RNA levels did not change. Transcriptomics data indicated that SLC16A10 can enhance the function of ribosome. Furthermore, targeted metabolomics data and ELISA results demonstrated SLC16A10 mainly affected the transport of phenylalanine into the cells. Then, phenylalanine was added to the cell culture medium after SLC16A10 overexpression, melanin synthesis in cells furtherly increased, which verified that SLC16A10 enhances melanogenesis by promoting the uptake of phenylalanine. Finally, we found that SLC16A10 expression increased after UVB irradiation. Knockdown SLC16A10 reduced UVB-induced melanin production and phenylalanine uptake by cells. In summary, SLC16A10 enhances melanogenesis by promoting the uptake of phenylalanine, and upregulation SLC16A10 is likely responsible for the UVB-induced hyperpigmentation as well.

The whitening efficacy of a compound formula examined using an ultraviolet-induced skin melanization model

BACKGROUND

In Eastern culture, a fair complexion is the standard of beauty, leading to appearance-related distress among women with darker skin or facial pigmentation. Women seek whitening cosmetics to enhance their skin tone or correct their pigmentation, but their safety and effectiveness are paramount factors to consider. In this study, we evaluated the safety and whitening effects of a compound formula denoted as TEST comprising astaxanthin, nicotinamide, arbutin, and tranexamic acid.

METHODS

Primary skin irritation and skin-whitening efficacy were examined. Three qualified melanization areas were treated with TEST, 7% ascorbic acid, or a blank. Skin color, the individual type angle (ITA°), and the melanin index (MI) were compared among treatment areas.

RESULTS

TEST did not induce a skin response and exhibited a significantly higher ITA° than the blank, while no significant difference was observed with that of 7% ascorbic acid. Furthermore, the MI of TEST was significantly reduced posttreatment.

CONCLUSIONS

TEST could be integrated into spot-fading and skin-whitening cosmeceuticals or functional cosmetics.

An update on the safety of hydroquinone

Hydroquinone has been used for years for multiple conditions, including melasma, post-inflammatory hyperpigmentation, dyschromia from photoaging, and solar lentigines. It is known to be a very effective lightening agent, but several concerns have been raised about this widely used agent. The recent U.S. ban on over-the-counter skin lightening products containing hydroquinone has prompted further questioning of the safety of this widely used agent. While there have been prior informative, large-scale reviews on the safety of hydroquinone, new findings have since been reported. Here, we provide an updated review of studies published in the past 15 years on hydroquinone safety.

Artificial Intelligence-Assisted Optimization of Antipigmentation Tyrosinase Inhibitors: De Novo Molecular Generation Based on a Low Activity Lead Compound

Artificial intelligence (AI) de novo molecular generation is a highly promising strategy in the drug discovery, with deep reinforcement learning (RL) models emerging as powerful tools. This study introduces a fragment-by-fragment growth RL forward molecular generation and optimization strategy based on a low activity lead compound. This process integrates fragment growth-based reaction templates, while target docking and drug-likeness prediction were simultaneously performed. This comprehensive approach considers molecular similarity, internal diversity, synthesizability, and effectiveness, thereby enhancing the quality and efficiency of molecular generation. Finally, a series of tyrosinase inhibitors were generated and synthesized. Most compounds exhibited more improved activity than lead, with an optimal candidate compound surpassing the effects of kojic acid and demonstrating significant antipigmentation activity in a zebrafish model. Furthermore, metabolic stability studies indicated susceptibility to hepatic metabolism. The proposed AI structural optimization strategies will play a promising role in accelerating the drug discovery and improving traditional efficiency.

Tricholoma matsutake polysaccharides suppress excessive melanogenesis via JNK-mediated pathway: Investigation in 8- methoxypsoralen induced B16-F10 melanoma cells and clinical study

Skin hyperpigmentation is a worldwide condition associated with augmented melanogenesis. However, conventional therapies often entail various adverse effects. Here, we explore the safety range and depigmentary effects of polysaccharides extract of Tricholoma matsutake (PETM) in an in vitro model and further evaluated its efficacy at the clinical level. An induced-melanogenesis model was established by treating B16-F10 melanoma cells with 8-methoxypsoralen (8-MOP). Effects of PETM on cell viability and melanin content were examined and compared to a commonly used depigmentary agent, α-arbutin. Expressions of key melanogenic factors and upstream signaling pathway were analysed by quantitative PCR and western blot. Moreover, a placebo-controlled clinical study involving Chinese females with skin hyperpigmentation was conducted to measure the efficacy of PETM on improving facial pigmented spots, melanin index, and individual typology angle (ITA°). Results demonstrated that PETM (up to 0.5 mg/mL) had little effect on the viability and motility of B16-F10 cells. Notably, it significantly suppressed the melanin content and expressions of key melanogenic factors induced by 8-MOP in B16-F10 melanoma cells. Western blotting results revealed that PETM inhibited melanogenesis by inactivating c-Jun N-terminal kinase (JNK), and this inhibitory role could be rescued by JNK agonist treatment. Clinical findings showed that PETM treatment resulted in a significant reduction of facial hyperpigmented spot, decreased melanin index, and improved ITA° value compared to the placebo-control group. In conclusion, these in vitro and clinical evidence demonstrated the safety and depigmentary efficacy of PETM, a novel polysaccharide agent. The distinct mechanism of action of PETM on melanogenic signaling pathway positions it as a promising agent for developing alternative therapies.

Melanin Biopolymers in Pharmacology and Medicine-Skin Pigmentation Disorders, Implications for Drug Action, Adverse Effects and Therapy

Melanins are biopolymeric pigments formed by a multi-step oxidation process of tyrosine in highly specialized cells called melanocytes. Melanin pigments are mainly found in the skin, iris, hair follicles, and inner ear. The photoprotective properties of melanin biopolymers have been linked to their perinuclear localization to protect DNA, but their ability to scavenge metal ions and antioxidant properties has also been noted. Interactions between drugs and melanins are of clinical relevance. The formation of drug-melanin complexes can affect both the efficacy of pharmacotherapy and the occurrence of adverse effects such as phototoxic reactions and discoloration. Because the amount and type of melanin synthesized in the body is subject to multifactorial regulation-determined by both internal factors such as genetic predisposition, inflammation, and hormonal balance and external factors such as contact with allergens or exposure to UV radiation-different effects on the melanogenesis process can be observed. These factors can directly influence skin pigmentation disorders, resulting in hypopigmentation or hyperpigmentation of a genetic or acquired nature. In this review, we will present information on melanocyte biology, melanogenesis, and the multifactorial influence of melanin on pharmacological parameters during pharmacotherapy. In addition, the types of skin color disorders, with special emphasis on the process of their development, symptoms, and methods of treatment, are presented in this article.

The Emerging Role of Visible Light in Melanocyte Biology and Skin Pigmentary Disorders: Friend or Foe?

Electromagnetic radiation, notably visible light (VL), has complicated effects on human skin, particularly pigmentation, which have been largely overlooked. In this review, we discuss the photobiological mechanisms, pathological effects, clinical applications and therapeutic strategies of VL at varying wavelengths on melanocyte biology and skin pigmentary disorders. Different VL wavelengths may impose positive or negative effects, depending on their interactions with specific chromophores, photoaging, ROS production, circadian rhythm and other photon-mediated reactions. Further in vivo and in vitro studies are required to establish the pathologic mechanisms and application principles of VL in pigmentary disorders, as well as optimal photoprotection with coverage against VL wavelengths.

Exploring the Potential and Limitations of Chat Generative Pre-trained Transformer (ChatGPT) in Generating Board-Style Dermatology Questions: A Qualitative Analysis

This article investigates the limitations of Chat Generative Pre-trained Transformer (ChatGPT), a language model developed by OpenAI, as a study tool in dermatology. The study utilized ChatPDF, an application that integrates PDF files with ChatGPT, to generate American Board of Dermatology Applied Exam (ABD-AE)-style questions from continuing medical education articles from the Journal of the American Board of Dermatology. A qualitative analysis of the questions was conducted by two board-certified dermatologists, assessing accuracy, complexity, and clarity. Out of 40 questions generated, only 16 (40%) were deemed accurate and appropriate for ABD-AE study preparation. The remaining questions exhibited limitations, including low complexity, lack of clarity, and inaccuracies. The findings highlight the challenges faced by ChatGPT in understanding the domain-specific knowledge required in dermatology. Moreover, the model's inability to comprehend the context and generate high-quality distractor options, as well as the absence of image generation capabilities, further hinders its usefulness. The study emphasizes that while ChatGPT may aid in generating simple questions, it cannot replace the expertise of dermatologists and medical educators in developing high-quality, board-style questions that effectively evaluate candidates' knowledge and reasoning abilities.

Clinical Applications of Polypodium leucotomos (Fernblock®): An Update

Exposure to sun radiation leads to higher risk of sunburn, pigmentation, immunosuppression, photoaging and skin cancer. In addition to ultraviolet radiation (UVR), recent research indicates that infrared radiation (IR) and visible light (VIS) can play an important role in the pathogenesis of some of these processes. Detrimental effects associated with sun exposure are well known, but new studies have shown that DNA damage continues to occur long after exposure to solar radiation has ended. Regarding photoprotection strategies, natural substances are emerging for topical and oral photoprotection. In this sense, Fernblock^®, a standardized aqueous extract of the fern Polypodium Leucotomos (PLE), has been widely administered both topically and orally with a strong safety profile. Thus, this extract has been used extensively in clinical practice, including as a complement to photodynamic therapy (PDT) for treating actinic keratoses (AKs) and field cancerization. It has also been used to treat skin diseases such as photodermatoses, photoaggravated inflammatory conditions and pigmentary disorders. This review examines the most recent developments in the clinical application of Fernblock^® and assesses how newly investigated action mechanisms may influence its clinical use.

Comparison of the efficacy and safety of picosecond Nd:YAG laser (1,064 nm), picosecond alexandrite laser (755 nm) and 2% hydroquinone cream in the treatment of melasma: A randomized, controlled, assessor-blinded trial

Background

Increasing numbers of studies demonstrated that picosecond lasers (Picos) were effective and safe for melasma. However, A limited number of randomized controlled trials (RCTs) regarding Picos contribute to a modest level of evidence. Topical hydroquinone (HQ) remains to be the first-line therapy.

Objective

To compare the efficacy and safety of non-fractional picosecond Nd:YAG laser (PSNYL), non-fractional picosecond alexandrite laser (PSAL), and 2% HQ cream in the treatment of melasma.

Method

Sixty melasma patients with Fitzpatrick skin types (FST) III-IV were randomly assigned to the PSNY, PSAL, and HQ groups at a 1:1:1 ratio. Patients in PSNYL and PSAL groups received 3 laser sessions at 4-week intervals. The 2% HQ cream was applied twice daily for 12 weeks in patients of the HQ group. The primary outcome, the melasma area and severity index (MASI) score, was evaluated at weeks 0, 4, 8, 12, 16, 20, and 24. The patient assessment score by quartile rating scale was rated at weeks 12, 16, 20, and 24.

Results

Fifty-nine (98.3%) subjects were included in the analysis. Each group showed significant change from baseline in MASI scores from week 4 to week 24. The MASI score in the PSNYL group showed the greatest reduction compared to the PSAL group (p = 0.016) and HQ group (p = 0.018). The PSAL group demonstrated comparable MASI improvement as the HQ group (p = 0.998). The PSNYL group had the highest patient assessment score, followed by the PSAL group and then the HQ group, although only the differences between PSNYL and HQ groups at weeks 12 and 16 were significant. Four patients (6.8%) experienced recurrence. Other unanticipated events were transient and subsided after 1 week to 6 months.

Conclusion

The efficacy of non-fractional PSNYL was superior to that of non-fractional PSAL, which was not inferior to 2% HQ, thus non-fractional Picos providing an alternative for melasma patients with FSTs III-IV. The safety profiles of PSNYL, PSAL, and 2% HQ cream were similar.

Clinical Trial Registration

https://www.chictr.org.cn/showprojen.aspx?proj=130994, ChiCTR2100050089.

Expert recommendations on supportive skin care for non-surgical and surgical procedures

A thorough knowledge of non-surgical procedures (laser, peelings, injections, threads) and surgical procedures (combined surgeries and skin grafts), including contraindications and potential risks and side effects, (e.g. infection, hypopigmentation, hyperpigmentation, and scarring) is essential to be able to reduce their incidence and ensure the patient receives the most benefit from the procedure. Individuals with darker skin and of high Fitzpatrick phototype are at higher risk of dyschromias, notably melasma and post-inflammatory hyperpigmentation, which may be treated using aesthetic procedures but may also arise as a complication of some procedures. A group of experts in cosmetic surgery and dermatology reviewed the published literature and discussed recommendations for optimizing outcomes with practical advice on supportive skincare before, during and after non-surgical or surgical procedures. A broad-spectrum sunscreen with a high sun protection factor against UVB and high protection against UVA, especially long UVA, is essential for all treatment modalities for the prevention and potential improvement of pigmentation disorders. Supportive skin care management to prepare, cleanse and protect the skin and post-procedure skin care with healing and anti-inflammatory ingredients are recommended to speed up regeneration and wound healing whilst minimizing scarring and downtime. Additionally, adjunctive skin care to procedures with antioxidant, anti-ageing and lightening properties may enhance skin benefits.

The Low-Fluence Q-Switched Nd:YAG Laser Treatment for Melasma: A Systematic Review

Melasma is a common pigmentary disorder with a complex pathogenesis, of which the treatment is challenging. Conventional treatment often leads to inconsistent results with unexpected pigmentary side effects and high recurrence rates. Recently, the low-fluence Q-switched Nd:YAG laser (LFQSNY) has been widely used for treating melasma, especially in Asia. We reviewed literatures on the LFQSNY treatment of melasma published between 2009 and May 2022 to evaluate the efficacy and adverse events, including its combination therapy. A systematic PubMed search was conducted and a total of 42 articles were included in this study. It was hard to summarize the heterogenous studies, but LFQSNY appeared to be a generally effective and safe treatment for melasma considering the results of previous conventional therapies. However, mottled hypopigmentation has been occasionally reported to develop and persist as an adverse event of LFQSNY, which may be associated with the high accumulated laser energy. When used aggressively, even LFQSNY can induce hyperpigmentation via unwanted inflammation, especially in darker skin. Although few studies have reported considerable recurrence rates three months after treatment, unfortunately, there is a lack of the long-term follow-up results of LFQSNY in melasma. To enhance the effectiveness and reduce the adverse events, LFQSNY has been used in combination with other treatment modalities in melasma, including topical bleaching agents, oral tranexamic acid, chemical peeling, or diverse energy-based devices, which generally reduced side effects with or without significant superior efficacy compared to LFQSNY alone.