• The Korean Journal of Physiology and Pharmacology
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• v.16 no.4
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• pp.287-291
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• 2012

This study investigated the effects of proline-serine (PS) and valine-serine (VS) dipeptides on melanogenesis in Mel-Ab cells. Proline-serine and VS significantly inhibited melanin synthesis in a concentration-dependent manner, though neither dipeptide directly inhibited tyrosinase activity in a cell-free system. Both PS and VS down-regulated the expression of microphthalmia-associated transcription factor (MITF) and tyrosinase. In a follow-up study also described here, the effects of these dipeptides on melanogenesis-related signal transduction were quantified. Specifically, PS and VS induced ERK phosphorylation, though they had no effect on phosphorylation of the cAMP response element binding protein (CREB). These data suggest that PS and VS inhibit melanogenesis through ERK phosphorylation and subsequent down-regulation of MITF and tyrosinase. Properties of these dipeptides are compatible with application as skin-whitening agents.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.1
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• pp.53-61
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• 2018

Ethyl linoleate is an unsaturated fatty acid used in many cosmetics for its various attributes, such as antibacterial and anti-inflammatory properties and clinically proven to be an effective anti-acne agent. In this study, we investigated the effect of ethyl linoleate on the melanogenesis and the mechanism underlying its action on melanogenesis in B16F10 murine melanoma cells. Our results revealed that ethyl linoleate significantly inhibited melanin content and intracellular tyrosinase activity in ${\alpha}$-MSH-induced B16F10 cells, but it did not directly inhibit activity of mushroom tyrosinase. Ethyl linoleate inhibited the expression of microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase related protein 1 (TRP1) in governing melanin pigment synthesis. We observed that ethyl linoleate inhibited phosphorylation of Akt and glycogen synthase kinase $3{\beta}$ ($GSK3{\beta}$) and reduced the level of ${\beta}-catenin$, suggesting that ethyl linoleate inhibits melanogenesis through $Akt/GSK3{\beta}/{\beta}-catenin$ signal pathway. Therefore, we propose that ethyl linoleate may be useful as a safe whitening agent in cosmetic and a potential therapeutic agent for reducing skin hyperpigmentation in clinics.

• Korean Journal of Pharmacognosy
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• v.47 no.1
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• pp.18-23
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• 2016

This study was conducted to investigate the tyrosinase inhibitory and melanin production inhibitory activity of the distilled water extract of Dendropanax morbifera leaf (DMW) and the fermented extract by Lactobacillus plantarum (DMF). DMF was prepared by inoculation of L. plantarum after the extraction procedure with distilled water. Fermentation for 48 hours at $37^{\circ}C$ is the most effective condition in this study. In DPPH radical scavenging ability, $SC_{50}$ values of the fermented DMF was $37.9{\mu}g/ml$ as a result of more effective than DMW extract ($52.6{\mu}g/ml$). Moreover, tyrosinase inhibitory activity of DMF showed higher activity than DMW. In nontoxic concentration range, DMF showed strong melanin production inhibitory effect in ${\alpha}$-melanocyte stimulating hormone-stimulated B16F10 cell. As a result, the fermentation of the distilled water extract of D. morbifera leaf by L. plantarum could be applicable to functional materials production for skin-whitening agents.

• YAKHAK HOEJI
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• v.46 no.2
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• pp.137-142
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• 2002

Caesalpinia sappan L. has long been commonly used as emmenagogue, analgesic, and a cure for contusion and sprain as well as a remedy for thrombosis in the Oriental medicine. The main constituent of C. sappan is brazilein, which is an antioxidative substance that has a flavonoid structure. In this study, we examined the effect of butanol extract of C. sappan on proliferation and melanogenesis in B16/F10 melanoma cells. After 48h treatment of cells with various concentrations of butanol extract, the cells exhibited a dose-dependent inhibition in their proliferation without apotosis. Therefore, the growth retardation by the extract may be due to the cell arrest, not due to the cell death induced by cytotoxicity. We also estimated total melanin contents as a final product and activity of tyrosinase, a key enzyme, in melanogenesis of B16/F10 melanoma cells. Our result showed that the melanin contents and tyrosinase activity were decreased in butanol extract-treated cells in a dose dependent manner compared to control group. In conclusion, it was observed that butanol extract of C. sappan inhibited melanization of these cells and therefore butanol extract could be developed as skin whitening components of cosmetics.

• YAKHAK HOEJI
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• v.42 no.4
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• pp.353-358
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• 1998

The MeOH extract of the bark of Paeonia moutan showed potent inhibitory effect on the mushroom tyrosinase activity in vitro. The activity-guided fractionation of t he MeOH extract resulted in the isolation of three active compounds. The chemical structures of these compounds were elucidated by chemical and spectroscopic evidence as catechin, 1,2,3,6-tetra-O-galloyl-${\beta}$-D-glucose and 1,2,3,4,6-penta-0-galloyl-${\beta}$-D-glucose, respectively. Among them, the inhibitory activity by 1,2,3,6-tetra-galloyl-${\beta}$-D-glucose on mushroom tyrosinase was more potent $(IC_{50}=3.5\;{\mu}M)$ than that of kojic acid $(IC_{50}=8.7\;{\mu}M)$ ,but catechin enhanced the mushroom tyrosinase activity 50% in the concentration of 34.5M.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.277-286
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• 2022

Schizophragma hydrangeoides (S. hydrangeoides) is a vine endogenous to Jeju Island and Ulleungdo, where it grows attached to the foothills and rock surfaces. Previous research has mostly focused on the whitening effect of S. hydrangeoides leaf extract. In this study, we investigated S. hydrangeoides leaf extract further, and detected four phytochemicals in the extract: chlorogenic acid, quercetin-3-O-glucosyl-(1-2)-rhamnoside, quercetin-3-O-xylosyl-(1-2)-rhamnoside, and quercitrin. We pretreated human dermal fibroblast (HDFn) cells with previously established concentrations of the four compounds for 1 h before ultraviolet A (UVA) irradiation. Among the four compounds, quercetin-3-O-glucosyl-(1-2)-rhamnoside (Q-3-GR) best inhibited matrix metalloproteinase-1 (MMP-1) levels. Thus, we investigated the protective effects of Q-3-GR on photoaging and its underlying mechanisms. Q-3-GR significantly reduced MMP-1 production and inhibited MMP-1 protein expression in UVA-irradiated HDFn cells. Furthermore, Q-3-GR increased procollagen type I production and protein expression. Q-3-GR exerted its anti-photoaging effects by downregulating the mitogen-activated protein kinase/ activator protein-1 signaling pathway, and upregulating the transforming growth factor-β/Smad signaling pathway. Thus, S. hydrangeoides leaf-derived Q-3-GR is a potential potent cosmetic ingredient for UV-induced skin aging.

• Biomedical Science Letters
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• v.29 no.4
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• pp.242-248
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• 2023

Platelets are activated at the sites of vascular injury by a number of molecules, including adenosine diphosphate, collagen and thrombin. The full platelet aggregation is absolutely essential for the normal hemostasis. Glycyrrhiza glabra is a well-known medicinal herb that grows in various parts of the world and is known to have various effects such as antioxidant, anti-inflammatory, anti-atherogenic, anti-osteoporotic and skin-whitening. However, the platelet inhibitory effect of Glycyrrhiza glabra extract (GGE) has not been identified. In this study, we investigated if GGE inhibited platelet aggregation. We observed that GGE inhibited collagen-induced platelet aggregation, Ca²⁺ mobilization, and thromboxane A2 generation. In addition, GGE suppressed phosphorylation of phosphatidylinositol-3 kinase (PI3K), Akt and elevated phosphorylation of inositol 1,4,5-trisphosphate receptor (IP3R), vasodilator stimulated phosphoprotein (VASP). Taken together, GGE showed strong antiplatelet effects and may be used to block platelet-mediated cardiovascular diseases.

• Korean Journal of Pharmacognosy
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• v.30 no.4
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• pp.397-403
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• 1999

Tyrosinase plays an important role in the process of melanin polymer biosynthesis. Therefore, the enzyme inhibitors have been of great concern as cosmetics to have skin-whitening effects on the local hyperpigmentation. During the search for new inhibitory compounds on melanin polymer biosynthesis from natural sources, MeOH extracts of 589 higher plants were tested for the inhibitory effect on tyrosinase activity by the muschroom tyrosinase assay in vitro. Among plants tested, the leaves of Cercis chinensis exhibited potent inhibitory effect on mushroom tyrosinase activity. Subsequently seven active compounds were isolated from the ethyl acetate soluble part of acetone extract of the leaves of C. chinensis by the activity guided fractionation monitoring the inhibitory effect on tyrosinase activity. Their chemical structures were identified as $kaempferol-3-0-{\alpha}-L-rhamnoside$, quercitrin, $myricetin-3-0-{\alpha}-L-rhamnoside$, myricetin-3-0-(2'-O-galloyl)- ${\alpha}$ -L-rhamopyranoside (desmanthin), (-)-epicatechin-3-0-gallate, (-)-epigallocatechin-3-0-gallate, and methyl gallate on the basis of the speculation of spectral data and chemical reaction. Among the flavonol rhamnosides, myricetin-3-0-(2'-O-galloyl)- -L-rhamnoside(desmanthin) showed most potent inhibitory effect on tyrosinase activity and the structure of B-ring in flavonol moiety was related to the activity. (-)-Epigallocatechin-3-O-gallate having pyrogallol group in flavan-3-ol moiety exhibited more potent inhibitory effect than (-)-epicatechin-3-0-gallate having catechol group in flavan-3-ol moiety on mushroom tyrosinase activity.

• Fisheries and Aquatic Sciences
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• v.23 no.3
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• pp.6.1-6.9
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• 2020

Background: Halophyte plant (HPs), a salt-resistant flora, has been reported to provide several health benefits, but the knowledge of its cosmeceutical potential is still ambiguous. Here, 70% ethanol extracts of 22 HPs collected from along the coast of South Korea were investigated for their potentials of antioxidant, anti-aging, and whitening properties for use as materials in novel cosmeceuticals. Methods: Antioxidant activities were determined by DPPH (1,1-diphenyl-2-pricrylhydrazyl) free radical and hydrogen peroxide scavenging assays, and skin aging-related enzyme activities (anti-elastase, anti-collagenase, anti-hyaluronidase, and anti-tyrosinase) were evaluated by using the spectrophotometric method. Results: Among the 22 HPs, we found that Ischaemum antephoroides f. coreana and Atriplex gmelinii extracts presented the strongest scavenging effects against DPPH free radical and hydrogen peroxide, respectively. Our finding additionally suggested that Salicornia europaea extract might provide a major source of anti-elastase and anti-hyaluronidase; meanwhile, Rosa rugosa extract showed the highest anti-collagenase effect. Furthermore, the highest tyrosinase inhibitory activity was possessed by Spartina anglica extract. Conclusion: These findings may suggest that halophyte plants showing biological activities may be potent inhibitors of tyrosinase, elastase, collagenase, and hyaluronidase and could be useful for application in cosmeceuticals.

• Korean Journal of Pharmacognosy
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• v.33 no.2 s.129
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• pp.130-136
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• 2002

Melanogenesis is a physiological process resulting in the synthesis of melanin pigments, which play a crucial protective role against skin photocarcinogenesis. The heart wood of Caesalpinia sappan L.(C. sappan) has long been commonly used in Oriental folk medicines to promote blood circulation, and as an emmenagogue, analgesic or anti-inflammatory agent as well as a remedy for thrombosis. From the heartwood, many constituents have been purified and among them, brazilin and hematoxylin are two of the most abundant. This present study was designed to investigate the inhibitory effect of butanol extract from C. sappan on proliferation and melanogenesis in Melan-a cells. After 48 h treatment of these cells with various concentrations of butanol extract, the cells showed a dose-dependent inhibition in their proliferation without apoptotic cell death. Therefore, the growth retardation by the extract may be due to the cell arrest or cell differentiation. We also estimated total melanin content as a final product and activity of tyrosinase, a key enzyme, of melanogenesis in Melan-a cells. The melanin content and tyrosinase activity were deσeased in extract-treated cells in a dose dependent manner compared to control group. The butanol extract also resulted in a decrease of melanin content in ${\alpha}-melanocyte-stimulating$ hormone (MSH)-induced melanogenesis, indicating that butanol extract of C. sappan could be developed as skin whitening components of cosmetics.