Inhibition of melanogenesis by Aster yomena callus pellet extract in melanoma cells and patients with skin pigmentation

Molecular understanding of the therapeutic potential of melanin inhibiting natural products

With the development of society and the improvement of people's living standards, there is an increasing demand for melanin-inhibiting products that prioritize health, safety, and efficacy. Therefore, the development of natural products that can safely and efficiently inhibit melanin synthesis is of great social significance and has significant market potential. In this paper, by reviewing the literature reported in recent years, we summarized the natural products with inhibition of melanin synthesis effects that have been put into or not yet put into the market, and classified them according to the chemical groups of their compounds or the extraction methods of the natural products. Through the summary analysis, we found that these compounds mainly include terpenoids, phenylpropanoids, flavonoids and so on, while the natural product extracts mainly include methanol extracts, ethanol extracts, and aqueous extracts. Their main inhibition of melanin synthesis mechanisms include: (1) direct inhibition of tyrosinase activity; (2) down-regulation of the α-MSH-MC1R, Wnt, NO, PI3K/Akt and MAPK pathways through the expression of MITF and its downstream genes TYR, TRP-1, and TRP-2; (3) antioxidant; (4) inhibition of melanocyte growth through cytotoxicity; (5) inhibition of melanosome production and transport. This paper provides an in-depth discussion on the research progress of whitening natural products and their market value. The aim is to offer guidance for future research and development of natural skin whitening products.

Ginsenoside Re inhibits melanogenesis and melanoma growth by downregulating microphthalmia-associated transcription factor

Panax ginseng, also known as Korean ginseng, is a traditional remedy widely used in Asian countries. Its major active compounds are ginsenosides, specifically triterpenoid saponins. Among them, one notable ginsenoside called Re has shown various biological effects, including anti-cancer and anti-inflammatory properties. However, the potential beneficial effects of Re on melanogenesis and skin cancer remain poorly understood. To investigate this, we conducted a comprehensive study using biochemical assays, cell-based models, a zebrafish pigment formation model, and a tumor xenograft model. Our results revealed that Re effectively inhibited melanin biosynthesis in a dose-dependent manner by competitively inhibiting the activity of tyrosinase, an enzyme involved in melanin production. Moreover, Re significantly reduced the mRNA expression levels of microphthalmia-associated transcription factor (MITF), a key regulator of melanin biosynthesis and melanoma growth. Furthermore, Re decreased the protein expression of MITF and its target genes, including tyrosinase, TRP-1, and TRP-2, through a partially ubiquitin-dependent proteasomal degradation mechanism, mediated by the AKT and ERK signaling pathways. These findings indicate that Re exerts its hypopigmentary effects by directly inhibiting tyrosinase activity and suppressing its expression via MITF. Additionally, Re demonstrated inhibitory effects on skin melanoma growth and induced tumor vascular normalization in our in vivo experiments. This study represents the first evidence of Re-mediated inhibition of melanogenesis and skin melanoma, shedding light on the underlying mechanisms. These promising preclinical findings warrant further investigation to determine the suitability of Re as a natural agent for treating hyperpigmentation disorders and skin cancer.

Discovery of amphotericin B, an antifungal drug as tyrosinase inhibitor with potent anti-melanogenic activity

Tyrosinase, a rate-limiting enzyme for melanin production, has been the most efficient target for the development of depigmenting agents. Although hydroquinone, kojic acid, and arbutin are the most well-known tyrosinase inhibitors, their adverse effects are inevitable. In the present study, an in silico drug repositioning combined with experimental validation was performed to search for novel potent tyrosinase inhibitors. Docking-based virtual screening results revealed that, among the 3210 FDA-approved drugs available in the ZINC database, amphotericin B, an antifungal drug exhibited the highest binding efficiency against human tyrosinase. Results from tyrosinase inhibition assay demonstrated that amphotericin B could inhibit the activity of mushroom and cellular tyrosinases, especially from MNT-1 human melanoma cells. Molecular modeling results revealed that amphotericin B/human tyrosinase complex exhibited high stability in an aqueous environment. Melanin assay results demonstrated that amphotericin B significantly suppressed melanin production in α-MSH-induced B16F10 murine melanoma and MNT-1 human melanoma cell lines better than the known inhibitor, kojic acid. Mechanistically, amphotericin B treatment significantly activated ERK and Akt signaling pathways, resulting in the decreased expression of MITF and tyrosinase. The obtained results may pursue pre-clinical and clinical studies to examine the possibility of using amphotericin B as an alternative treatment for hyperpigmentation disorders.

Plants as Modulators of Melanogenesis: Role of Extracts, Pure Compounds and Patented Compositions in Therapy of Pigmentation Disorders

The kingdom of plants as a "green biofabric" of valuable bioactive molecules has long been used in many ailments. Currently, extracts and pure compounds of plant origin are used to aid in pigmentation skin problems by influencing the process of melanogenesis. Melanin is a very important pigment that protects human skin against ultraviolet radiation and oxidative stress. It is produced by a complex process called melanogenesis. However, disturbances in the melanogenesis mechanism may increase or decrease the level of melanin and generate essential skin problems, such as hyperpigmentation and hypopigmentation. Accordingly, inhibitors or activators of pigment formation are desirable for medical and cosmetic industry. Such properties may be exhibited by molecules of plant origin. Therefore, that literature review presents reports on plant extracts, pure compounds and compositions that may modulate melanin production in living organisms. The potential of plants in the therapy of pigmentation disorders has been highlighted.

Immunological Effects of Aster yomena Callus-Derived Extracellular Vesicles as Potential Therapeutic Agents against Allergic Asthma

Plant-derived extracellular vesicles, (EVs), have recently gained attention as potential therapeutic candidates. However, the varying properties of plants that are dependent on their growth conditions, and the unsustainable production of plant-derived EVs hinder drug development. Herein, we analyzed the secondary metabolites of Aster yomena callus-derived EVs (AYC-EVs) obtained via plant tissue cultures and performed an immune functional assay to assess the potential therapeutic effects of AYC-EVs against inflammatory diseases. AYC-EVs, approximately 225 nm in size, were isolated using tangential flow filtration (TFF) and cushioned ultracentrifugation. Metabolomic analysis, using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS), revealed that AYC-EVs contained 17 major metabolites. AYC-EVs inhibited the phenotypic and functional maturation of LPS-treated dendritic cells (DCs). Furthermore, LPS-treated DCs exposed to AYC-EVs showed decreased immunostimulatory capacity during induction of CD4+ and CD8+ T-cell proliferation and activation. AYC-EVs inhibited T-cell reactions associated with the etiology of asthma in asthmatic mouse models and improved various symptoms of asthma. This regulatory effect of AYC-EVs resembled that of dexamethasone, which is currently used to treat inflammatory diseases. These results provide a foundation for the development of plant-derived therapeutic agents for the treatment of various inflammatory diseases, as well as providing an insight into the possible mechanisms of action of AYC-EVs.

Inhibitory activity of soybean (Glycine max L. Merr.) Cell Culture Extract on tyrosinase activity and melanin formation in alpha-melanocyte stimulating Hormone-Induced B16-F10 melanoma cells

BACKGROUND

Hyperpigmentation, which causes excessive melanin synthesis and accumulation, is an important issue in the cosmetic industry. Since compounds developed against hyperpigmentation often come with side effects such as skin irritation and contact dermatitis, new studies focus on the use of natural agents that have no side effects.

METHODS AND RESULTS

In this study, it was found that the effects of soybean cell culture extract (SCE) on alpha-melanocyte-stimulating hormone (α-MSH) induced melanogenesis in B16-F10 murine melanoma cells. The cells were incubated with SCE for 48 h after treatment with α‑MSH for 24 h to analysis the melanin content, cellular tyrosinase activity, and gene and protein expression. SCE at 1 mg/mL decreased melanin content and tyrosinase activity by 34% and 24%, respectively, compared to the α-MSH-treated group, which did not decrease cell viability. In addition, SCE (1 mg/mL) downregulated the expression of tyrosinase (TYR), tyrosinase-related protein (TRP)-1, tyrosinase-related protein (TRP)-2, and microphthalmia-associated transcription factor (MITF) genes 1.5-, 1.5-, 2-, and 2-fold, respectively. Furthermore, SCE inhibited the expression of TYR, TRP1, and TRP2 by decreasing the expression of MITF, as shown in a western blot assay.

CONCLUSIONS

This study suggests that SCE reveals dose-dependent inhibition of melanin synthesis through the suppression of tyrosinase activity as well as molecular levels of TYR, TRP1, TRP2, and MITF in B16-F10 murine melanoma cells. Therefore, SCE has the potential to be an effective and natural skin-whitening agent for application in the cosmetic industry.

The Modulation of Melanogenesis in B16 Cells Upon Treatment with Plant Extracts and Isolated Plant Compounds

Plants are a rich source of secondary metabolites that exhibit numerous desired properties. The compounds may influence the biology of melanocytes, pigment cells that produce melanin, by modulating numerous signaling pathways, including cAMP/PKA, MAPKs and PI3K/AKT. Its downstream target is microphthalmia-associated transcription factor, responsible for the expression of the tyrosinase enzyme, which plays a major role in melanogenesis. Therefore, this literature review aims to provide insights related to melanogenesis modulation mechanisms of plant extracts and isolated plant compounds in B16 cells. Database searches were conducted using online-based library search instruments from 2012 to 2022, such as NCBI-PubMed and Google Scholar. Upregulation or downregulation of signaling pathways by phytochemicals can influence skin hypo- and hyperpigmentation by changing the level of melanin production, which may pose a significant cosmetic issue. Therefore, plant extracts or isolated plant compounds may be used in the therapy of pigmentation disorders.

Chrysoeriol Enhances Melanogenesis in B16F10 Cells Through the Modulation of the MAPK, AKT, PKA, and Wnt/β-Catenin Signaling Pathways

Chrysoeriol is a 3′-O-methoxy flavone, chemically a derivative of luteolin, which is commonly found across the plant kingdom. Chrysoeriol is of great scientific interest because of its promising anti-inflammatory, anti-cancer, antioxidative, anti-lipase, anti-xanthin oxidase, and antimicrobial activities against multidrug-resistant (MDR) bacterial pathogens; however, its effects on melanogenesis have not yet been elucidated. Here, we report a novel effect of chrysoeriol on melanogenesis in B16F10 cells. Chrysoeriol treatment significantly increased the expression of the melanogenic enzymes tyrosinase (TRY), tyrosinase-related protein-1 (TRP-1), and TRP-2 and upregulated the expression of microphthalmia-associated transcription factor (MITF) in a concentration-dependent manner. Furthermore, chrysoeriol suppressed the phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) in a concentration-dependent manner. In addition, chrysoeriol treatment increased the phosphorylation of p38 mitogen-activated protein kinase (MAPK), glycogen synthase kinase (GSK)-3β, β-catenin, and protein kinase A (PKA) and decreased the production of β-catenin, which is involved in the transcriptional activation of MITF in melanogenesis. Finally, the structure–activity relationship (SAR) of chrysoeriol and its derivatives, including luteolin and apigenin, with regard to their melanin inhibitory activity was also investigated; we identified the significance of the 4′-OH group and C-3′ methoxylation in melanogenesis. Together, these findings indicate that chrysoeriol promotes melanogenesis in B16F10 cells by upregulating the expression of melanogenic enzymes through the MAPK, phosphatidylinositol 3-kinase (PI3K)/AKT, PKA, and Wnt/β-catenin signaling pathways; thus, chrysoeriol may be used as a cosmetic ingredient to promote melanogenesis or as a therapeutic agent against hypopigmentation disorders.