• BMB Reports
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• v.42 no.3
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• pp.178-183
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• 2009

Tyrosinase (TYR) plays a critical role in cellular melanogenesis and, thus, has been the major target of pharmacological approaches for the control of skin pigmentation. This study examined an alternative molecular approach using TYR-small interfering RNA (siRNA) to control melanogenesis in the human melanocytes. Both the mRNA and protein levels of TYR were significantly lowered by TYR-siRNA treatment, whereas TYR-related protein 1 and TYR-related protein 2 displayed no such changes. TYR-siRNA treatment inhibited the cellular melanin synthesis from the externally supplied TYR substrate L-tyrosine. TYR-siRNA also suppressed melanin synthesis and decreased the viability of cells exposed to ultraviolet radiation, supporting a critical role of melanin in protection against ultraviolet radiation. These results suggest that molecular approaches using siRNA targeted to the enzymes of melanogenic pathway may provide a novel strategy for the control of cell pigmentation.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2121-2132
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• 2018

Abnormal melanin synthesis results in several hyperpigmentary disorders such as freckles, melanoderma, age spots, and other related conditions. In this study, we investigated the anti-melanogenic effects of an extract from the microalgae Chlamydomonas reinhardtii (CE) and potential mechanisms responsible for its inhibitory effect in B16F10, normal human epidermal melanocyte cells, and human skin-equivalent models. The CE extract showed significant dose-dependent inhibitory effects on ${\alpha}$-melanocyte-stimulating, hormone-induced melanin synthesis in cells. Additionally, the CE extract exhibited suppressive effects on the mRNA and protein expression of microphthalmia-associated transcription factor, tyrosinase, tyrosinase-related protein-1, and tyrosinase-related protein-2. The CE extract also inhibited the phosphorylation of protein kinase A and extracellular signal-related kinase, which function as upstream regulators of melanogenesis. Using a three-dimensional, reconstructed pigmented epidermis model, the CE-mediated, anti-pigmentation effects were confirmed by Fontana-Masson staining and melanin content assays. Taken together, CE extract can be used as an anti-pigmentation agent.

• The Korea Journal of Herbology
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• v.28 no.1
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• pp.9-14
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• 2013

Objectives： Bletillae Rhizoma, the roots of Bletilla striata, is used to restrain the leakage of blood and stop bleeding. It can cure the sores, ulcers, and chapped skin. This study was designed to investigate the collagen metabolism, elastase and tyrosinase activity of Bletillae Rhizoma extract (BR). Methods : The effects of BR on type I procollagen production and collagenase activity in human normal fibroblasts Hs68 after UVB (312 nm) irradiation were measured by ELISA method. The elastase activity, tyrosinase activity, and L-DOPA oxidation after treatment of BR were measured as well. Results : In the present study, the collagen production (type I procollagen) was significantly increased to $15.7{\pm}1.8$ ng/ml at a concentration of BR 100 ${\mu}g/ml$ in UVB damaged Hs68 cells. The increased collagenase activity after UVB damage was significantly recovered to $42.7{\pm}0.7%$, $54.5{\pm}3.5%$, and $38.4{\pm}0.9%$ by BR 10, 30, and 100 ${\mu}g/ml$. The activities of BR 10 mg/ml on tyrosinase activity was significantly reduced to $45.1{\pm}8.4%$ as well. However, there were no significant effects on the elastase activity and the L-DOPA oxidation. Conclusion : BR showed the promoting effects of collagen synthesis and inhibitory effects of collagenase activity in Hs68, human normal fibroblast cells. And these could be thought to have the anti-wrinkle effects and whitening effects in vitro. These results suggest that BR may have potential as an anti-aging ingredient in cosmetic treatment.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.22 no.2
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• pp.104-117
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• 2009

Objective : Melanin is one of the most important facor in skin color. Melanin protects human skin from ultraviolet radiation otherwise it causes melanin pigmentation. So this experiment is carried out for test whether Scutellaria baicalensis Georgi(SBG) inhibits melanin synthesis and tyrosinase activity in mouse B16 melanoma cells. Method : The melanin synthesis inhibition effects of SBG were examined by in vitro melanin production assay. We assessed inhibitory effects of SBG on melanin contents from B16F1 melanoma cell, on tyrosinase activity(cell and cell free system), effect of SBG on the expression tyrosinase, Microphthalmia-associated Transcription Factor(MITF), Extracellular signal-regulated Kinase(ERK). Result : SBG inhibited melanin synthesis induced $\alpha$-MSH($\alpha$-Melanin Stimulating Hormone) in B16F1. SBG inhibited tyrosinase activity and expression. And SBG down-regulates MITF and stimulated ERK activation in B16F1. Conclusion : According to above results, SBG was improved its suppression effect to the inhibition of melanin synthesis, tyrosinase activation, and tyrosinase promotor activation. So SBG is considered to be used for an strong source of skin whitening effect.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.27 no.1
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• pp.111-118
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• 2001

A novel melanogenic inhibitory compound, Phytoclear-EL1 (5,10-diacetyl-3-benzoyllathyrol) was isolated from Euphorbiae lathyridis. The effects of EL1 on culture normal human melanocytes (NHM) were assessed. EL1 reduced the melanin synthesis of NHM by 40% at a concentration of 2 $\square$g/ml without any apparent cytotoxicity. We also have found that the treatment of the cells with EL1 decreased the tyrosinase activity by 29% in situ. To elucidate the action mechanism of EL1, we investigated the changes in mRNA levels of tyrosinase, TRP-1 and TRP-2 using RT-PCR technique. AS a result, the mRNA levels of tyrosinase, TRP-1 and TRP-2 were markedly reduced by EL1 treatment. These results suggest that Phytoclear-EL1 is a novel whitening agent that is effective in human melanocytes.

• Korean Journal of Korean Medical Institute of Dermatology and Aesthetics
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• v.1 no.1
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• pp.41-52
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• 2005

The aim of this study was to investigate the effect of Fructus Forsythiae on the melanogenesis. To determine whether Fructus Forsythiae methanol extract suppress melanin synthesis in cellular level, HM3KO human melanoma cells were cultured in the presence of various concentrations of Fructus Forsythiae methanol extract and the effects on cell proliferation, tyrosinase activity and melanin contents were examined. Treatment with Fructus Forsythiae methanol extract inhibited tyrosinase activity, regulate melanin biosynthesis as the key enzyme in melanogenesis, in a dose-dependent manner. And also suppressed melanin contents as a dose dependent manner without cytotoxicity morphological change. It was observed that the color of cell pellets was totally different from the control. These results suggest that the inhibitory effect of Fructus Forsythiae methanol extract on melanogenesis is due to the suppression of tyrosinase in HM3KO cells and Fructus Forsythiae is a candidate for an efficient whitening agent.

• Journal of Ginseng Research
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• v.45 no.5
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• pp.555-564
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• 2021

Background: Ginsenosides of Panax ginseng are used to enhance skin health and beauty. The present study aimed to investigate the potential use of ginsenoside Rf (Rf) from Panax ginseng as a new anti-pigmentation agent. Methods: The anti-melanogenic effects of Rf were explored. The transcriptional activity of the cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) and the expression levels of tyrosinase, microphthalmia-associated transcription factor (MITF), and tyrosinase-related proteins (Tyrps) were evaluated in melanocytes and UV-irradiated ex vivo human skin. Results: Rf significantly inhibited Forskolin (FSK) or UV-stimulated melanogenesis. Consistently, cellular tyrosinase activity and levels of MITF, tyrosinase, and Tyrps were downregulated. Furthermore, Rf suppressed MITF promoter activity, which was stimulated by FSK or CREB-regulated transcription coactivator 3 (CRTC3) overexpression. Increased CREB phosphorylation and protein kinase A (PKA) activity induced by FSK were also mitigated in the presence of Rf. Conclusion: Rf can be used as a reliable anti-pigmentation agent, which has a scientifically confirmed and reproducible action mechanism, via inhibition of CREB/MITF pathway.

• Korean Journal of Medicinal Crop Science
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• v.22 no.5
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• pp.331-338
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• 2014

Dendrobium moniliforme (DM) is a valuable and versatile herbal medicine with the anecdotal claims of antioxidant and anti-inflammation. In the present study, we investigated the whitening and anti-wrinkling effects of DM under various conditions with B16F10 melanoma cells and human dermal fibroblasts. The DM extract inhibited melanin contents and tyrosinase activity in a dose-dependent manner, compared with untreated group. Treatment of the DM extract effectively suppressed the ${\alpha}$-MSH-stimulated melanin formation, tyrosinase activity and dendrite outgrowth. Moreover, the ${\alpha}$-MSH-induced mRNA expressions of tyrosinase-related protein-1 (TRP-1) and tyrosinase-related protein-2 (TRP-2) and protein expression of tyrosinase were significantly attenuated by DM treatment. We also investigated the DM increased the production of type I procollagen and inhibited TNF-${\alpha}$-induced mRNA expressions of MMP-1, -3 in the human dermal fibroblast. These results indicate that DM may be a great cosmeceutical ingredient for its whitening and anti-wrinkle effects.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.135-149
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• 2002

To date, research on the regulation of melanogenesis has focused on factors which affect tyrosinase, the rate-limiting enzyme in the melanogenic pathway, by searching for chemicals which competitively inhibit tyrosinase function. Many types of tyrosinase inhibitors have been developed, but no satisfactory results have been made clinically until now, To find a new whitening agent, which effectively inhibits melanogenesis, we synthesized several compounds and selected compounds by cell-based assay system. Finally, 3, 4, 5-trimethoxy cinnamaie thymol ester(TCTE, Melasolv) was selected and the effects of TCTE on melanogenesis were investigated. Treatment of mouse-derived melanocyte melan-a cells with TCTE results in a marked down-regulation of tyrosinase activity. 80% decrease of tyrosinase activity occurs with 30uM TCTE treatment for 72 hours without affecting cell growth. The inhibition of tyrosinase activity is dose-dependent and melanin content was also decreased to 40%. From the in vitro tyrosinase assay using cell extract, TCTE does not act as a direct inhibitor of the enzyme. Treatment of melan-a cultures with TCTE blocks the increase in tyrosinase activity by either forskolin, 3-isobutyl-1-methtyl-xanthine. TCTE decreased the expression of tyrosinase, TRP-1 without effects on TRP-2 protein expression through the down regulation of tyrosinase and TRP-1 mRNA. From the results of cAMP immunoassays, intracellular levels of the cyclin nucleotide are unaffected in cells treated with TCTE. The inhibitory effects of melanin synthesis were also shown in reconstitute human epidermis model by topical application. These findings suggest that TCTE can be used for studying the regulation of melanogenesis and depigmenting agent.

• Journal of Environmental Health Sciences
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• v.22 no.1
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• pp.1-4
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• 1996

I have conducted two testings to find out which water is better for drinking water. First, I made 20 mM L-DOPA solutions by solving L-DOPA (3,4-Dihydroxyphenylalanine) in tap water, Waters' mineral water and reverse osmotic water. Then I measured activities after adding Tyrosinase (purifide enzyme, step 3), which was extracted from Salanum melongena(mad apple), in each L-DOPA solution. Second, I solved 0.1, 0.5 and 0.9% salt in each 20 mM L-DOPA distilled water to measure activity of each salt solution. The results of the testings are as follows: 1. 10 minutes after adding Salanum melongena(mad apple) tyrosinase in each L-DOPA solution, activity of Waters' mineral water was 0.867 tap water 0.777 and reverse osmotic water 0.742. 2. Activity of Waters' mineral water was higher than that of tap water by 10.4% and higher then reverse osmotic by 14.4%. 3. Activity of Waters' mineral water was much higher than that of 0.9% salt water by 41.8%. 4. The optimum pH of Salanum melongena (mad apple) tyrosinase is 9.0. Most enzymes working in the human metabolism are alkaline and body fluids' pH also alkaline. In conclusion, an alkaline water is believed better than an acidic water for drinking.