• Archives of Plastic Surgery
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• v.38 no.6
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• pp.725-732
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• 2011

Purpose: Skin grafting is one of the most commonly used methods in reconstructive plastic surgery field, but complications such as color change, contracture or hypertrophy are common problems. However, pathophysiology of the color change after skin graft is not yet determined and no animal model is established. Methods: Full thickness skin grafts were performed on the dorsum of C57BL/6 mice. Serial chronological gross inspection for color change and pigmentation were examined. Melanin pigments were traced by Fontana-Masson staining and semi-quantitative analysis was performed. In addition, immunohistochemical staining of S-100, Micropthalmia related Transcription Factor (MITF) and Melan-A antibodies were also performed to observe melanocytes and their changes. Results: After skin graft, color change and pigment spots were observed in the graft. Fontana-Masson staining showed melanin pigments in the epidermal and dermal layers in all mice. Immunohistochemistry staining to S-100, MITF, Melan-A antibodies showed melanocytes at the basal layer of epidermis and dermis. Conclusion: In conclusion, we have established an animal model for skin pigmentation after skin graft. We believe this study may be useful in understanding of the behavior of melanocytes after skin graft.

• Korean Journal of Veterinary Research
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• v.55 no.2
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• pp.145-148
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• 2015

Four 3-day-old piglets with retarded growth were submitted to the Animal and Plant Quarantine Agency for diagnosis. Necropsy showed that one piglet had black spots ranging from 2 mm to 1 cm in diameter in the cerebellum, lungs, regional lymph nodes, and cecum. Histological findings were consistent with the gross appearance in which melanin pigmentation was observed in the organs mentioned above. Based on Fontana-Masson staining, we diagnosed this animal with systemic melanosis. To the best of our knowledge, this is the first case of systemic melanosis in black breeds of swine in Korea.

• 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.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.375-380
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• 2018

We have previously found that mycelia culture broth of eight kinds of traditional herbal extracts fermented with Phellinus linteus (previously named as 8-HsPLCB) not only inhibited melanin and tyrosinase activity, but also reduced the contents of melanogenesis-related proteins, including tyrosinase and microphthalmia-associated transcription factor, in 3-isobutyl-1-methylxanthine-stimulated B16F0 melanoma cells. For a further study, the effect of 8-HsPLCB against skin pigmentation in brown guinea pigs with ultraviolet B (UVB)-induced hyperpigmentation was investigated. 8-HsPLCB (3%) and arbutin (2%) as positive controls were applied topically twice daily for 4 weeks to the hyperpigmented areas. 8-HsPLCB showed skin-lightening effect as effective as arbutin, one of the most widely used in whitening cosmetics. Melanin index values as the degree of pigmentation showed a significant reduction week by week post 8-HsPLCB treatment and then substantially reduced by 4 weeks. The degree of depigmentation after 4 weeks of topical application with 8-HsPLCB was 32.2% as compared with before treatment (0 week). Moreover, using Fontana-Masson staining and hematoxylin-eosin staining, 8-HsPLCB reduced melanin pigmentation in the basal layer of the epidermis and epidermal thickness changes exposed to the UV-B irradiation as compared with non-treatment and vehicle treatment. The intensity of the skin-lightening effect of 8-HsPLCB was similar to arbutin. These results suggest that the skin-lightening effect of 8-HsPLCB might be resulted from inhibition of melanin synthesis by tyrosinase in melanocytes. To conclude, 8-HsPLCB treatment showed reduction of the melanin pigment and histological changes induced by UV irradiation in brown guinea pigs.

• Journal of Mushroom
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• v.14 no.4
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• pp.225-231
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• 2016

Hot water extracts from 16 domestic edible mushrooms including Pleurotus ferulae (Lanzi) X.L. Mao, Lentinula edodes (Berk.) Pegler, and Hypsizygus marmoreus (Peck) H.E. Bigelow, which are commercially available, were used for determining the cosmetic potential of these mushrooms. In this study, we carried out in vitro functional experiments to determine the inhibitory effects of these extracts on L-DOPA oxidation of tyrosinase and melanin synthesis. Based on the results of these experiments, H. marmoreus (Peck) H.E. Bigelow No. 10 and No. 15 were selected for further analysis. We analyzed the melanin synthesis inhibitory activity, TRP1 and MITF expression via real-time PCR, and Fontana Masson staining in artificial skin $Neoderm^{(R)}-ME$. Taken together, we observed that the hot water extract from H. marmoreus (Peck) H.E. Bigelow (No. 15) had better whitening effect than the extracts of other mushrooms. Thus, it can be a potential source of skin-whitening agent.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.431-437
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• 2014

Synthetic compounds that are used in the clinic to regulate skin hyperpigmentation, such as arbutin, hydroquinone, and kojic acid, are only moderately effective. But, their use is limited by side effects. As part of an effort to overcome the limitations, we developed resveratrol-enriched rice (RR) using genetic engineering technique. Each of resveratrol and rice has been reported to produce anti-melanogenic effects. Therefore, we hypothesized that RR would show more anti-melanogenic effects than those of resveratrol or rice alone. Anti-melanogenic effect of RR was done by using melan-a mouse melanocytes. The depigmenting efficacy was then observed following topical application of the RR to UVB-stimulated hyperpigmented dorsal skin of guinea pigs. Treatment with RR extract resulted a $21.4{\pm}0.7%$ decrease in tyrosinase expression at melan-a cells. Colorimetric analysis showed a significantly lower depigmenting value by day 9 following treatment with RR in UVB-irradiated guinea pigs the dorsal skin (p<0.01), indicating that RR produced a depigmentation effect. By staining with Fontana-Masson stain, we found that the RR-treated group had more effect histopathologically in epidermal melanin production than resveratrol or rice alone-treated group. RR was associated with reduction in the levels of microphthalmia-associated transcription factor (MITF), and downregulation of tyrosinase and tyrosinase-related protein (TRP-2) expression, leading to inhibit epidermal melanin production by western blot analysis. This study suggests that the resveratrol-enriched rice may be a promising candidate in regulating skin pigmentation with UVB exposure.

• Biomolecules & Therapeutics
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• v.24 no.1
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• pp.85-93
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• 2016

We already reported that genetically engineered resveratrol-enriched rice (RR) showed to down-regulate skin melanogenesis. To be developed to increase the bioactivity of RR using calli from plants, RR was adopted for mass production using plant tissue culture technologies. In addition, high-pressure homogenization (HPH) was used to increase the biocompatibility and penetration of the calli from RR into the skin. We aimed to develop anti-melanogenic agents incorporating calli of RR (cRR) and nanoparticles by high-pressure homogenization, examining the synergistic effects on the inhibition of UVB-induced hyperpigmentation. Depigmentation was observed following topical application of micro-cRR, nano-calli of normal rice (cNR), and nano-cRR to ultraviolet B (UVB)-stimulated hyperpigmented guinea pig dorsal skin. Colorimetric analysis, tyrosinase immunostaining, and Fontana-Masson staining for UVB-promoted melanin were performed. Nano-cRR inhibited changes in the melanin color index caused by UVB-promoted hyperpigmentation, and demonstrated stronger anti-melanogenic potential than micro-cRR. In epidermal skin, nano-cRR repressed UVB-promoted melanin granules, thereby suppressing hyperpigmentation. The UVB-enhanced, highly expressed tyrosinase in the basal layer of the epidermis was inhibited by nano-cRR more prominently than by micro-cRR and nano-cNR. The anti-melanogenic potency of nano-cRR also depended on pH and particle size. Nano-cRR shows promising potential to regulate skin pigmentation following UVB exposure.

• Microbiology and Biotechnology Letters
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• v.36 no.1
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• pp.72-81
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• 2008

The effect of genistein on melanin synthesis was studied using in vitro and in vivo model. Genistein inhibited melanin synthesis in cultured melan-a cells dose dependently. Tyrosinase activity was decreased by genistein treatment in melan-a cells, but genistein did not inhibit tyrosinase directly. Genistein did not affect the expression of tyrosinase in melan-a cells. Genistein inhibited the activity of ${\alpha}$-glucosidase in virtro and the glycosylation of tyrosinase in melan-a cells. The resulting unsaturated glycosylation of tyrosinase makes it unstable and disturb correct transportation. To further clarify the effect of genistein on the melanogenesis, we established UVB-induced hyperpigmentation on the shaved backs of brown guinea pigs. The animals were exposed to UVB radiation once a week for three consecutive weeks. Genistein (1 and 2%) or vehicle alone as a control were then topically applied to the hyperpigmented areas daily. Genistein showed significant lightening effect on the UVB-induced hyperpigmentation in five weeks. Depigmenting effect was prominent in 2% genistein treatment with Fontana-Masson staining. In conclusion, genistein may be a useful agent for skin whitening.