The role of systemic treatments for skin lightening

Glutathione as a skin-lightening agent and in melasma: a systematic review

Hyperpigmentary disorders, including melasma, are challenging to treat. Glutathione has anti-melanogenic and antioxidant properties, which led to its use as a skin-lightening agent. Our objective was to review the published evidence and literature on the efficacy and safety of glutathione as a skin-lightening agent and in the treatment of melasma. A literature search was done in the PubMed, Embase, and Cochrane library databases using the search terms "glutathione as a skin-lightening agent" and "glutathione in melasma" for the past 10 years. The level of evidence, strength of recommendation, and risk of bias assessment were evaluated. Among various forms of topical glutathione, glutathione 0.5% was significantly more effective compared to glutathione 0.1% and placebo. For glutathione alone versus glutathione plus microneedling, more improvement was seen. Five randomized controlled trials and a single open-arm clinical study on oral glutathione at doses of 250 mg once a day, 250 mg twice a day, and 500 mg once a day showed a significant reduction in the melanin index compared to placebo. The combination of topical 2% glutathione plus oral glutathione was superior to monotherapy alone. There was only one placebo-controlled study on intravenous (IV) glutathione [6/16 (37.5%) vs. 3 (18.7%), (p0.054)]. The risk of bias assessment showed that almost an equal number of studies have low and high risk of bias. Topical versus oral glutathione both provide moderately efficacious skin-lightening outcomes that are localized versus generalized and have minimal versus substantial adverse effects, but they are unsustainable, with variable costs. IV glutathione is contraindicated due to lack of efficacy and side effects. It may work more as an antioxidant in melasma.

Antioxidant and Skin-Whitening Efficacy of a Novel Decapeptide (DP, KGYSSYICDK) Derived from Fish By-Products

The skin is vulnerable to damage from ultraviolet rays and oxidative stress, which can lead to aging and pigmentation issues. This study investigates the antioxidant and whitening efficacy of a decapeptide (DP, KGYSSYICDK) derived from marine fish by-products and evaluates its potential as a new skin-whitening agent. DP demonstrated high antioxidant activity, showing comparable or superior performance to Vitamin C (Vit. C) in ferric reducing antioxidant power (FRAP) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assays. In hydrogen peroxide (H2O2)-treated HaCaT cells, DP increased cell viability and reduced reactive oxygen species (ROS) generation. Furthermore, DP inhibited tyrosinase activity and decreased melanin production in α-melanocyte stimulating hormone (α-MSH)-induced B16F10 melanoma cells in a dose-dependent manner. Reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that DP reduces the mRNA expression of MITF, tyrosinase, and MC1R, thus suppressing melanin production. DP exhibits strong binding interactions with multiple amino acid residues of tyrosinase, indicating potent inhibitory effects on the enzyme. These results suggest that DP possesses significant antioxidant and whitening properties, highlighting its potential as a skin-whitening agent. Future research should focus on optimizing DP's structure and exploring structure-activity relationships.

Evaluating the Application Potential of a Recombinant Ganoderma Protein as Bioactive Ingredients in Cosmetics

The aim of this study was to evaluate the application potential of a recombinant fungal immunomodulatory protein from Ganoderma lucidum (rFIP-glu). First, a recombinant plasmid pPIC9K::FIP-glu-His was transferred into Pichia pastoris for the production of protein. The protein was then to assess its free radical scavenging abilities and the effect on the viability of both human immortalized keratinocytes (HaCaT cells) and mouse B16-F10 melanoma cells (B16 cells) in vitro, followed by the effect on the melanin synthesis of B16 cells. The results of SDS-PAGE and western blot showed that rFIP-glu was successfully expressed. Furtherly, a bioactivity assay in vitro indicated that the scavenging rate of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals reached 84.5% at 6.0 mg/mL (p ≤ 0.0001) of rFIP-glu, showing strong antioxidant activity. Subsequently, a safety evaluation demonstrated that rFIP-glu promoted the proliferation of HaCaT cells, with the cell viability reaching 124.3% at 48 μg/mL (p ≤ 0.01), regarding the cell viability of B16 cells after exposure to rFIP-glu (48 μg/mL) significantly inhibited, to 80.7% (p ≤ 0.01). Besides, rFIP-glu inhibited the melanin synthesis of B16 cells in a dose-dependent manner from 100–1000 μg/mL, and rFIP-glu at 500 μg/mL (p ≤ 0.01) exhibited the highest intracellular melanin amount reduction of 16.8%. Furthermore, a mechanism analysis showed that rFIP-glu inhibited tyrosinase (TYR) activity by up-regulating the expression of the microphthalmia-associated transcription factor (MITF) and down-regulating the gene expression of TYR and tyrosinase-related protein-1 (TYRP-1), thus inhibiting melanin synthesis. The data implied that rFIP-glu had significant antioxidant activity and whitening potency. It should be used as raw materials for cosmeceutical applications.

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

Key challenges in the management of pigmentary disorders such as melasma and postinflammatory hyperpigmentation are their resistance to treatment, tendency to recur after treatment, and the risk of exacerbating hyperpigmentation with many treatment modalities. The second article in this 2-part continuing medical education series on pigmentary disorders focuses on the evidence behind medical and procedural treatments of dyschromias, including photoprotection, topical lightening agents, oral agents, chemical peels, and laser therapy.

Natural products in cosmetics

The global cosmetics market reached US$500 billion in 2017 and is expected to exceed US$800 billion by 2023, at around a 7% annual growth rate. The cosmetics industry is emerging as one of the fastest-growing industries of the past decade. Data shows that the Chinese cosmetics market was US$60 billion in 2021. It is expected to be the world's number one consumer cosmetics market by 2050, with a size of approximately US$450 billion. The influence of social media and the internet has raised awareness of the risks associated with the usage of many chemicals in cosmetics and the health benefits of natural products derived from plants and other natural resources. As a result, the cosmetic industry is now paying more attention to natural products. The present review focus on the possible applications of natural products from various biological sources in skin care cosmetics, including topical care products, fragrances, moisturizers, UV protective, and anti-wrinkle products. In addition, the mechanisms of targets for evaluation of active ingredients in cosmetics and the possible benefits of these bioactive compounds in rejuvenation and health, and their potential role in cosmetics are also discussed.

Update on Melasma-Part II: Treatment

Melasma is a prevalent chronic relapsing pigmentary disorder that affects photoexposed areas, especially in women of childbearing age. Although there is currently no curative treatment available for melasma, this manuscript critically reviews the knowledge regarding photoprotection, topical and oral therapies, and procedures such as peelings, laser, and microneedling that represent the main strategies for control and prevention of this disease. As the pathogenesis of melasma is not entirely understood, there are prospects for the development of new therapeutic strategies that might act on the pathways that promote sustained pigmentation rather than merely decreasing melanin synthesis and removing melanin from the epidermis.

A study of botulinum toxin type A for the treatment of ultraviolet B-induced hyperpigmentation: a prospective, randomized, controlled trial

BACKGROUND

Botulinum toxin type A (BTX-A) has been used experimentally under various dermatological conditions. Recent studies have revealed a preventive effect of BTX-A against ultraviolet B (UVB)-induced skin hyperpigmentation.

OBJECTIVE

We examined the effect of BTX-A for the treatment of UVB-induced hyperpigmentation in human.

MATERIAL AND METHODS

A prospective, double-blind, randomized controlled trial was conducted. UVB irradiation induced five separate hyperpigmented squares on the abdomen. Seven days after irradiation, all squares were randomly assigned to five intervention groups: control, 0.9% normal saline injection, 12 units (1:2.5), 6 units (1:5), and 4 units (1:7.5) of onabotulinum toxin injections. The lightness index (L*), hyperpigmentation improvement score rated by a blinded physician, and participant satisfaction scores were obtained at 14, 21, and 28 days after injection.

RESULTS

Fifteen participants (mean age 36.9 years, Fitzpatrick skin types III-IV) completed the study. The BTX-A (1:2.5)-treated site had a lower degree of hyperpigmentation at all time points, as measured by mean L* and hyperpigmentation improvement scores. However, there were no statistically significant differences between the groups. Participants were most satisfied with the control site.

CONCLUSION

Intradermal BTX-A injection had no therapeutic effect on UVB-induced hyperpigmentation. However, the role of BTX-A injections in the treatment of other hyperpigmentary conditions requires further elucidation.

Efficacy and safety of 755 nm Q-switched Alexandrite Laser for Hori's nevus: a retrospective analysis of 482 Chinese women

To evaluate the efficacy and safety of 755 nm Q-Switched alexandrite laser for Hori's nevus in a large cohort of Chinese women. We retrospectively analyzed the efficacy and safety of 755 nm Q-Switched alexandrite laser for Hori's nevus. Reduction in pigment was evaluated using a 4-score method. A total of 482 patients, aged 16 to 52 years, were included in this analysis. Patients were treated with 755 nm Q-Switched alexandrite laser at fluence levels of 5-8 J/cm² for 2-4 treatment sessions. Following the treatments, 53% of patients showed over 75% reductions in pigment while 50-75% reductions in pigment were observed in 28% of patients. The rest displayed less than 50% improvements. Efficacy was positively correlated with the number of treatment sessions (p < 0.0001). Adverse reactions were temporary, mild erythema, and edema. A small portion of patients (15%) had hyperpigmentation, which disappeared within 2-6 months. 755 nm Q-Switched alexandrite laser is safe and has moderate benefits for Hori's nevus. Because its efficacy is positively correlated with the number of treatment sessions, increase in treatment sessions possibly could achieve a better outcome.

Whitening effect of novel peptide mixture by regulating melanosome biogenesis, transfer and degradation

Peptides are short chain of amino acids linked by peptide bonds. They are widely used as effective and biocompatible active ingredients in cosmetic industry. In this study, we developed novel peptide mixture and identified its anti-pigmentation effect on melanocytes and keratinocytes. Our results revealed that peptide mixture inhibited melanosome biogenesis through the regulation of microphthalmia-associated transcription factor, a key factor of melanogenesis in melanocytes. And we observed that peptide mixture inhibited melanosome uptake through the reduction of protease-activated receptor 2, a phagocytosis-related receptor in keratinocytes. Furthermore, peptide mixture activated autophagy system resulting in degradation of transferred melanosomes in keratinocytes. The anti-pigmentation effect of multi-targeting peptide mixture was assessed in a human skin equivalent model (MelanoDerm). Melanin contents in epidermal layer were significantly decreased by topical treatment of peptide mixture, suggesting that it can be applied as a novel cosmetics material having a whitening function.

UP256 Inhibits Hyperpigmentation by Tyrosinase Expression/Dendrite Formation via Rho-Dependent Signaling and by Primary Cilium Formation in Melanocytes

Skin hyperpigmentation is generally characterized by increased synthesis and deposition of melanin in the skin. UP256, containing bakuchiol, is a well-known medication for acne vulgaris. Acne sometimes leaves dark spots on the skin, and we hypothesized that UP256 may be effective against hyperpigmentation-associated diseases. UP256 was treated for anti-melanogenesis and melanocyte dendrite formation in cultured normal human epidermal melanocytes as well as in the reconstituted skin and zebrafish models. Western blot analysis and glutathione S-transferase (GST)-pull down assays were used to evaluate the expression and interaction of enzymes related in melanin synthesis and transportation. The cellular tyrosinase activity and melanin content assay revealed that UP256 decreased melanin synthesis by regulating the expression of proteins related on melanogenesis including tyrosinase, TRP-1 and -2, and SOX9. UP256 also decreased dendrite formation in melanocytes via regulating the Rac/Cdc42/α-PAK signaling proteins, without cytotoxic effects. UP256 also inhibited ciliogenesis-dependent melanogenesis in normal human epidermal melanocytes. Furthermore, UP256 suppressed melanin contents in the zebrafish and the 3D human skin tissue model. All things taken together, UP256 inhibits melanin synthesis, dendrite formation, and primary cilium formation leading to the inhibition of melanogenesis.

Efficacy and Safety of an Oral Nutritional (Dietary) Supplement Containing Pinus pinaster Bark Extract and Grape Seed Extract in Combination with a High SPF Sunscreen in the Treatment of Mild-to-Moderate Melasma: A Prospective Clinical Study

Background: Melasma is a common hyperpigmentation disorder, characterized by light-to-dark brown patches, usually distributed on sun-exposed areas of the body. The objective of this study was to evaluate the efficacy and tolerability of an oral nutritional supplement containing Pinus pinaster and Grape seed extract, vitamins and minerals, used concomitantly with a high SPF sunscreen in 30 women with mild-to-moderate facial melasma. Methods: Efficacy was assessed by measurement of the Melasma Area and Severity Index (MASI), instrumental analysis of the lesions (Mexameter®, VISIA®)) and Patient’s and Physician’s Global Assessment (PGA). Results: The MASI score decreased significantly compared with baseline at days 28, 56, and 84. Mexameter® analysis showed a significant decrease of ∆M (difference in the melanin index between melasma and adjacent area). VISIA® results also showed a reduction in the number and areas of UV pigmented spots and in the areas of melasma overtime. Both the Patient’s and Physician’s Global Assessment showed that the product led to an improvement of the lesions in terms of depigmentation and had positive cosmetic features without adverse events. Conclusion: The oral supplement subject of this study in combination with high SPF sunscreen was effective and well-tolerated for treatment of mild to moderate facial melasma.