• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.4
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• pp.938-944
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• 2005

Down-regulation of melanin synthesis is required for recovery of pigmentary disorders and it is known that direct inhibitors of tyrosinase suppress melanin synthesis. We screened several oriental medicinal plants using B16/Fl0 cells and found that the methanolic extract of Cnidii Rhizoma down-regulated melanin synthesis effectively. Although the proliferation of Bl6/Fl0 cells was decresed by the methanolic extract of Cnidii Rhizoma, it did not appear necrosis. Bl6/F10 cells incubated with the methanolic extract of Cnidii Rhizoma showed reduced pigmentation and tyrosinase activity. Western blotting revealed that the amount of tyrosinase was decreased by the methanolic extract of Cnidii Rhizoma. These results suggest that the inhibitary effect of the methanolic extract of Cnidii Rhizoma on melanogenesis is due to the suppression of tyrosinase in Bl6/F10 cells and Cnidii Rhizoma is a candidate for an efficient whitening agent.

• Journal of Life Science
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• v.33 no.5
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• pp.445-454
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• 2023

Hair graying is the result of a malfunction in the signaling pathways that control melanogenesis, and it is activated by UV light, melanocyte-stimulating hormone (MSH), stem cell factor (SCF), Wnt, and endothelin-1 (ET-1). To prevent hair graying, synthetic and natural compounds can be used to stimulate melanogenesis effectively under the control of tyrosinase, tyrosine hydroxylase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF). This article describes a crucial strategy to resolve the problem of hair graying, as well as recent advances in the signaling pathway related to melanogenesis and hair graying. In particular, the article reviews potentially effective therapeutic agents that promote melanogenesis, such as antioxidants that modulate catalase, methionine sulfoxide reductase, and sirtuin 1 (SIRT1) activators including resveratrol, fisetin, quercetin, and ginsenoside. It also discusses vitiligo inhibitors, such as corticosteroids, calcineurin inhibitors, and palmitic acid methyl ester, as well as activators of telomerase expression and activity, including estrogen, androgen, progesterone, and dihydrotestosterone. Furthermore, it explores compounds that can inhibit hair graying, such as latanoprost, erlotinib, imatinib, tamoxifen, and levodopa. In conclusion, this article focuses on recent research trends on compounds that promote melanin production related to hair graying.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.1
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• pp.29-32
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• 2004

Inhibition of the early N-glycosylation process in the endoplasmic reticulum prevents the activation of tyrosinase, a key enzyme for melanin biosynthesis. This work aims at evaluating the increased activity of N-glycosylation inhibitors in vitro b, employing a nano-sized pH-sensitive liposome as a delivery carrier. Melexsome, a pH-sensitive nano carrier loaded with glycosylation inhibitos, was prepared by the hydration method with phospholipids and cholresterol-based amphiphiles. Inhibitory effects of Melexsome on the N-glycosylation process were evaluated by EndoH ＆ PNGaseF digestion and the western blotting. Melanin synthesis was also monitored after treatment with Melexsome Interestingly, Melexsome effectively increased the efficacy of N-glycosylation inhibitors. Melexsome was also much more efficiently translocated into the cytoplasm as observed in CLSM. These results demonstrated that the amphiphilic lipid-based pH-sensitive nano-carriers could be, used as an efficient delivery system for N-glycosylation inhibitor to enhance the effects of skin whitening cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.2
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• pp.63-70
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• 1997

It has been observed that local increase in melanin synthesis or uneven distribution can cause local hyperpigmintation or spot. Pigmentary disorders are caused by various factors, including inflammation, imbalance of hormones, and genetic disorder. Recently the harmfulness of Ultraviolet radiation is increasing due to destruction of ozone layer. Excessive exposure to UV radiation caused post-inflammatory pigmentation. Most women want to avoid uneven skin pigmentation. To satisfy this desire many cosmetic companies have been developing melanogenesis inhibitors and finding promising active agents for use in cosmetic preparations for skin whitening. In cosmetic preparations, many inhibitors such as kojic acid, arbutin, ascorbic acid, and licorice extracts6 have been used as whitening purpose. Plant extracts having an inhibitory effect on melanin formation may be a good choice for cosmetic purpose because of their relatively lower side effects. Therefore, we screened 285 plant extracts for their inhibitory activity in tyrosinase. Of the plant extracts, ramulus mori extracts showed potent tyrosinase inhibition activity. We also identified the active compound in the extract.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.167-171
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• 2010

The present study aims to evaluate Cordyceps militaris water extract (CMWE) with a view to develop melanogenesis inhibitors. Inhibitory activities of CMWE against tyrosinase, L-DOPA(L-3,4-dihydroxyphenylalanine) oxidation, and melanin biosynthesis in B16 mouse melanoma cells were investigated. CMWE, at $5000\;{\mu}g/ml$, inhibited tyrosinase activity of 71% and DOPA oxidation of 40% as reacting with L-DOPA. Furthermore, B16 mouse melanoma cell survived over 50% from low to high dose on MTT assay, and CMWE markedly inhibited (> 50%) melanin synthesis at $5000\;{\mu}g/ml$. The inhibitory effect of CMWE on melanogenesis was attributed to enhancement of tyrosinase degradation. Key enzyme of melanin biosynthesis is tyrosinase which catalyses a beginning step from tyrosine to DOPA quinine and melanin formation step, respectively. These results indicated that CMWE may be a potential source of novel whitening agents for cosmetic or therapeutic application.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.3
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• pp.115-121
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• 1997

To identify inhibitors of melanogenesis, we compared the effects of 5 compounds on mushroom tyrosinase, human melanocytic tyrosinase activity and melanin content. The cytotoxicyty of the components were also tested on cultured human melanoctes. Kojic acid showed marked inhibitory effect both on mushroom and human tyrosinase activity. This action of kijic acid is stronger than that of ascorbic acid. Arbutin inhibited human tyrosinase activity of cultured melanocytes although it had slightly inhibitory effect on mushroom tyrosinase activity. Azelaic acid had no effect on human tyrosinase activity. Melanin production was inhibited significantly by kojic acid and tranexamic acid. MTT assay showed that all of the compounds were non-cytotoxic to melanocytes at the concentrations tested. These results suggest that the effect of kojic acid on cultured meanocytes involve inhibition of tyrosinase activity and melanogenesis without affection the cell number.

• Journal of Pharmaceutical Investigation
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• v.36 no.2
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• pp.103-107
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• 2006

In order to develop hydroquinone analogues for topical delivery, a structure-activity relationship study has been performed. A series of 2-substituted hydroquinones were tested for their ability to inhibit mushroom tyrosinase, alter melanin release and exert cytotoxicity in B6-F10 melanocytes. The electronic property of the 2-substituents did not affect the tyrosinase inhibition nor melanocyte toxicity. However, lipophilicity did affect to some degree the tyrosinase inhibition. The discrepancy in the structure-activity relationship may be due to the poor aqueous solubility of select analogues. Compounds with steric bulk at the 2-position seems to be less soluble, not enabling the analogue to interact effectively with the tyrosinase enzyme. Among the analogues tested, 2-isopropyl hydroquinone seems to be the most promising candidate for topical delivery, being the least toxic analogue with moderate melanin release inhibition.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.206.3-207
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• 2003

The bioassay-guided fractionation of the methylene chloride soluble portion of a methanol extract of Gastrodia elata tubers led to the isolation of a new furfural, 5-(4-hydroxy-benzyloxymethyl)-furan-2-carbaldehyde (2), together with four known compounds (1, 3-5), which exhibited potent inhibitory activity at the concentration of 25 $\mu\textrm{g}$/ml on melanin biosynthesis in cultured B-16 mouse melanoma cells.

• Journal of Life Science
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• v.19 no.1
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• pp.75-80
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• 2009

Melanogenesis is a physiological process that results in the synthesis of melanin pigments. Tyrosinase is a key enzyme for melanin biosynthesis, and hyperpigmentation disorders are associated with abnormal accumulation of melanin pigments, which can be improved by treatment with depigmenting agents. Among the possible melanin-reducing compounds, tyrosinase inhibitors are most promising for preventing and treating pigmentation disorder and are used as skin-whitening agents in the cosmetic industry. In the present study, the effects of fucoidan on melanogenesis and tyrosinase activity of B16F10 melanoma cells were investigated. Melanin synthesis and tyrosinase activity in B16F10 melanoma cells were decreased in a dose-dependent manner by fucoidan. Melanin production and tyrosinase activity in B16F10 melanoma cells stimulated by a-melanocyte stimulating hormone (a-MSH) were inhibited by fucoidan with a dose-dependent manner compared to control. Fucoidan inhibited tyrosinase activity of B16F10 melanoma cells with a dose-dependent manner as assessed by 3,4-dihydroxyphenylalanine (DOPA) staining. In conclusion, these findings indicate that fucoidan, which inhibit melanin synthesis and tyrosinase activity, is an effective skin-whitening agent.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.649-650
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• 2003