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Inhibitory Effect of Avenanthramides (Avn) on Tyrosinase Activity and Melanogenesis in α-MSH-Activated SK-MEL-2 Cells: In Vitro and In Silico Analysis. Int J Mol Sci 2021; 22:ijms22157814. [PMID: 34360580 PMCID: PMC8345984 DOI: 10.3390/ijms22157814] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 07/12/2021] [Accepted: 07/16/2021] [Indexed: 11/22/2022] Open
Abstract
Melanin causes melasma, freckles, age spots, and chloasma. Anti-melanogenic agents can prevent disease-related hyperpigmentation. In the present study, the dose-dependent tyrosinase inhibitory activity of Avenanthramide (Avn)-A-B-C was demonstrated, and 100 µM Avn-A-B-C produced the strongest competitive inhibition against inter-cellular tyrosinase and melanin synthesis. Avn-A-B-C inhibits the expression of melanogenesis-related proteins, such as TRP1 and 2. Molecular docking simulation revealed that AvnC (−7.6 kcal/mol) had a higher binding affinity for tyrosinase than AvnA (−7.3 kcal/mol) and AvnB (−6.8 kcal/mol). AvnC was predicted to interact with tyrosinase through two hydrogen bonds at Ser360 (distance: 2.7 Å) and Asn364 (distance: 2.6 Å). In addition, AvnB and AvnC were predicted to be skin non-sensitizers in mammals by the Derek Nexus Quantitative Structure–Activity Relationship system.
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Xiao L, Zhang X, Chen Z, Li Y, Li B, Li L. ERK1/2 Pathway Is Involved in the Enhancement of Fatty Acids from Phaeodactylum tricornutum Extract (PTE) on Hair Follicle Cell Proliferation. BIOMED RESEARCH INTERNATIONAL 2020; 2020:2916104. [PMID: 33178821 PMCID: PMC7648671 DOI: 10.1155/2020/2916104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/21/2020] [Accepted: 09/27/2020] [Indexed: 11/17/2022]
Abstract
Extractions from Phaeodactylum tricornutum have been widely studied and evaluated to various biological effects. The aim of this study was to investigate the promotional effect of P. tricornutum extract (PTE) on the ERK1/2 signaling pathway involved in hair follicle cell proliferation. In order to illuminate the enhancement of PTE on hair growth by promoting proliferation of hair follicle cells, the activities of human hair follicle outer root sheath cell (HFORSC), human hair follicle germinal matrix cells (HFGMC), and hair epithelial melanocytes (HEM) were observed under PET treatment. Levels of keratins, PKCζ, ERK1/2, and p38 MAPK in hair follicle cells were determined by Western blotting to illustrate the mechanisms of PTE effects on hair growth. Analyzed by GC-MS, the main polyunsaturated fatty acids which were 9.43% of total fatty acids in PTE were linolenic acid, linoleic acid, eicosapentaenoic acid, and docosahexaenoic acid. Melanin content and tyrosinase activity in HEM were measured. The results showed that PTE exhibited remarkable enhancement on cell proliferation. Melanin production was inhibited by PTE treatment, while keratin-14, keratin-15, and keratin-17 levels on hair follicle cells were elevated at different concentrations. The promotions of ERK1/2 and p38 MAPK levels indicated that the ERK1/2 signaling pathway is involved in the proliferation of hair follicle cells. These results are the evidence that PTE potentially deserves further study as a new natural candidate for hair care applications.
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Affiliation(s)
- Lei Xiao
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510640, China
- Infinitus (China) Co., China
| | - Xia Zhang
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510640, China
| | - Zhiyi Chen
- Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangdong Key Laboratory of Agricultural Products Processing, Guangzhou 510610, China
| | - Yuting Li
- School of Chemical Engineering and Energy Technology, Dongguan University of Technology, College Road 1, Dongguan 523808, China
| | - Bing Li
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510640, China
| | - Lin Li
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, South China University of Technology, Guangzhou 510640, China
- School of Chemical Engineering and Energy Technology, Dongguan University of Technology, College Road 1, Dongguan 523808, China
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Lajis AFB, Ariff AB. Discovery of new depigmenting compounds and their efficacy to treat hyperpigmentation: Evidence from in vitro study. J Cosmet Dermatol 2019; 18:703-727. [PMID: 30866156 DOI: 10.1111/jocd.12900] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 01/22/2019] [Indexed: 12/19/2022]
Abstract
Human skin pigmentation is a result of constitutive and facultative pigmentation. Facultative pigmentation is frequently stimulated by UV radiation, pharmacologic drugs, and hormones whereby leads to the development of abnormal skin hyperpigmentation. To date, many state-of-art depigmenting compounds have been studied using in vitro model to treat hyperpigmentation problems for cosmetic dermatological applications; little attention has been made to compare the effectiveness of these depigmenting compounds and their mode of actions. In this present article, new and recent depigmenting compounds, their melanogenic pathway targets, and modes of action are reviewed. This article compares the effectiveness of these new depigmenting compounds to modulate several melanogenesis-regulatory enzymes and proteins such as tyrosinase (TYR), TYR-related protein-1 (TRP1), TYR-related protein-2 (TRP2), microphthalmia-associated transcription factor (MITF), extracellular signal-regulated kinase (ERK) and N-terminal kinases (JNK) and mitogen-activated protein kinase p38 (p38 MAPK). Other evidences from in vitro assays such as inhibition on melanosomal transfer, proteasomes, nitric oxide, and inflammation-induced melanogenesis are also highlighted. This article also reviews analytical techniques in different assays performed using in vitro model as well as their advantages and limitations. This article also provides an insight on recent finding and re-examination of some protocols as well as their effectiveness and reliability in the evaluation of depigmenting compounds. Evidence and support from related patents are also incorporated in this present article to give an overview on current patented technology, latest trends, and intellectual values of some depigmenting compounds and protocols, which are rarely highlighted in the literatures.
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Affiliation(s)
- Ahmad Firdaus B Lajis
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Malaysia.,Bioprocessing and Biomanufacturing Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Malaysia.,Institute of Bioscience, Universiti Putra Malaysia, Serdang, Malaysia
| | - Arbakariya B Ariff
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Malaysia.,Bioprocessing and Biomanufacturing Research Center, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Malaysia
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An inhibitory mechanism of action of a novel syringic-acid derivative on α-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis. Life Sci 2017; 191:52-58. [PMID: 28993145 DOI: 10.1016/j.lfs.2017.10.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 01/06/2023]
Abstract
AIMS To report the effects of a novel syringic-acid derivative, (R)-ethyl-2-acetamido-3-(4-hydroxy-3,5-dimethoxybenzoylthio)propanoate (EABTO), on melanin synthesis and to identify its mechanism of action in B16F1 melanoma cells. METHODS The effects of EABTO on melanin synthesis in B16F1 cells and human epidermal melanocytes and the influence on cell-free tyrosinase activity were evaluated. EABTO-induced cellular signaling cascades were studied by western blotting. KEY FINDINGS EABTO effectively decreased melanin synthesis in a dose-dependent manner but had no effect on cell-free tyrosinase activity. EABTO significantly decreased the expression of melanogenic enzymes such as tyrosinase, tyrosinase-related protein 1 (TRP-1), and TRP-2. EABTO decreased the amounts of phosphorylated cAMP response element-binding protein (CREB) and cyclic adenosine monophosphate (cAMP), thereby inhibiting expression of microphthalmia-associated transcription factor (MITF). Moreover, EABTO upregulated phosphorylated ERK. A specific ERK pathway inhibitor, PD98059, reduced EABTO-induced ERK phosphorylation and restored the expression of MITF and melanin content. SIGNIFICANCE EABTO inhibits melanogenesis in B16F1 melanoma cells via suppression of the cAMP-CREB pathway and activation of ERK, thus decreasing expression of MITF and of melanogenic enzymes.
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Pillaiyar T, Manickam M, Jung SH. Recent development of signaling pathways inhibitors of melanogenesis. Cell Signal 2017; 40:99-115. [PMID: 28911859 DOI: 10.1016/j.cellsig.2017.09.004] [Citation(s) in RCA: 129] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 09/10/2017] [Accepted: 09/10/2017] [Indexed: 02/08/2023]
Abstract
Human skin, eye and hair color rely on the production of melanin, depending on its quantity, quality, and distribution, Melanin plays a monumental role in protecting the skin against the harmful effect of ultraviolet radiation and oxidative stress from various environmental pollutants. However, an excessive production of melanin causes serious dermatological problems such as freckles, solar lentigo (age spots), melasma, as well as cancer. Hence, the regulation of melanin production is important for controlling the hyper-pigmentation. Melanogenesis, a biosynthetic pathway to produce melanin pigment in melanocyte, involves a series of intricate enzymatic and chemical catalyzed reactions. Several extrinsic factors include ultraviolet radiation and chemical drugs, and intrinsic factors include molecules secreted by surrounding keratinocytes or melanocytes, and fibroblasts, all of which regulate melanogenesis. This article reviews recent advances in the development of melanogenesis inhibitors that directly/indirectly target melanogenesis-related signaling pathways. Efforts have been made to provide a description of the mechanism of action of inhibitors on various melanogenesis signaling pathways.
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Affiliation(s)
- Thanigaimalai Pillaiyar
- PharmaCenter Bonn, Pharmaceutical Institute, Pharmaceutical Chemistry I, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany.
| | - Manoj Manickam
- College of Pharmacy and Institute of Drug Research and Development, Chungnam National, University, Daejeon 34134, Republic of Korea
| | - Sang-Hun Jung
- College of Pharmacy and Institute of Drug Research and Development, Chungnam National, University, Daejeon 34134, Republic of Korea
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From bench (laboratory) to bed (hospital/home): How to explore effective natural and synthetic PAK1-blockers/longevity-promoters for cancer therapy. Eur J Med Chem 2017; 142:229-243. [PMID: 28814374 DOI: 10.1016/j.ejmech.2017.07.043] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 07/19/2017] [Accepted: 07/21/2017] [Indexed: 12/19/2022]
Abstract
PAK family kinases are RAC/CDC42-activated kinases that were first found in a soil amoeba 4 decades ago, and 2 decades later, were discovered in mammals as well. Since then at least 6 members of this family have been identified in mammals. One of them called PAK1 has been best studied so far, mainly because it is essential not only for malignant cell growth and metastasis, but also for many other diseases/disorders such as diabetes (type 2), AD (Alzheimer's disease), hypertension, and a variety of inflammatory or infectious diseases, which definitely shorten our lifespan. Moreover, PAK1-deficient mutant of C. elegans lives longer than the wild-type by 60%, clearly indicating that PAK1 is not only an oncogenic but also ageing kinase. Thus, in theory, both anti-oncogenic and longevity-promoting activities are among the "intrinsic" properties or criteria of "clinically useful" PAK1-blockers. There are a variety of PAK1-blocking natural products such as propolis and curcumin which indeed extend the healthy lifespan of small animals such as C. elegans by inducing the autophagy. Recently, we managed to synthesize a series of potent water-soluble and highly cell-permeable triazolyl esters of COOH-bearing PAK1-blockers such as Ketorolac, ARC (artepillin C) and CA (caffeic acid) via "Click Chemistry" that boosts their anti-cancer activity over 500-fold, mainly by increasing their cell-permeability, and one of them called 15K indeed extends the lifespan of C. elegans. In this mini-review we shall discuss both synthetic and natural PAK1-blockers, some of which would be potentially useful for cancer therapy with least side effect (rather promoting the longevity as well).
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Kim YM, Cho SE, Seo YK. The activation of melanogenesis by p-CREB and MITF signaling with extremely low-frequency electromagnetic fields on B16F10 melanoma. Life Sci 2016; 162:25-32. [PMID: 27543340 DOI: 10.1016/j.lfs.2016.08.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 07/28/2016] [Accepted: 08/14/2016] [Indexed: 10/21/2022]
Abstract
Melanin in the skin determines the skin color, and decreased melanin causes many hypopigmentation disorders and increased damage to skin by ultraviolet B (UVB) light irradiation. Here, we stimulate melanogenesis in B16F10 melanoma cells by using specific frequencies of ELF-EMFs. In this study, we focus on the melanogenesis of EMF-ELFs and find that 60-75Hz ELF-EMFs upregulate melanin synthesis by stimulated expression of tyrosinase and TRP-1 through inhibition of phosphorylation ERK, activation of CREB, and MITF up-regulation in B16F10 melanoma cells. The results show that 60-75Hz ELF-EMFs significantly increase secreted melanin, cellular melanin content, and tyrosinase activity, and the cell mitochondria activity, cell viability, and cell membrane condition are unchanged. Furthermore, the protein expression level of MITF and p-CREB signaling pathway are significantly increased. Moreover, 60Hz ELF-EMFs reduce the phosphorylate of ERK in B16F10 melanoma cells. These findings indicate that stimulation of melanogenesis by using ELF-EMFs has therapeutic potential for treating hypopigmentation disorders such as vitiligo.
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Affiliation(s)
- Yu-Mi Kim
- Department of Medical Biotechnology (BK21 Plus team), Dongguk University, Seoul 100-715, Republic of Korea
| | - Sang-Eun Cho
- Department of Medical Biotechnology (BK21 Plus team), Dongguk University, Seoul 100-715, Republic of Korea
| | - Young-Kwon Seo
- Department of Medical Biotechnology (BK21 Plus team), Dongguk University, Seoul 100-715, Republic of Korea.
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Geranylgeranylacetone induces apoptosis via the intrinsic pathway in human melanoma cells. Biomed Pharmacother 2016; 82:15-9. [PMID: 27470333 DOI: 10.1016/j.biopha.2016.04.051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/25/2016] [Accepted: 04/25/2016] [Indexed: 11/23/2022] Open
Abstract
The aim of this study was to test the anti-cancer effects of geranylgeranylacetone (GGA), an isoprenoid compound, on human melanoma cells. Human melanoma cell lines G361, SK-MEL-2, and SK-MEL-5 were treated with GGA at various doses (1-100μM). Cell viability was measured by crystal violet assay. Western blot analysis was adopted to detect marker proteins of apoptosis. GGA significantly reduced the viability of G361, SK-MEL-2, and SK-MEL-5 human melanoma cells at concentrations above 10μM. Western blot analysis showed the phosphorylation of p38 MAPK and c-Jun N-terminal kinase (JNK) after GGA treatment, as well as activation of caspase-9, caspase-3, and poly(ADP-ribose) polymerase (PARP) cleavage. GGA also induced p53 and Bax expression, but did not affect expression of Bcl-2 and MITF. These findings suggest that GGA induces apoptosis through the intrinsic pathway. Accordingly, GGA should be considered for further development as a potential agent for melanoma.
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A novel peptide purified from the fermented microalga Pavlova lutheri attenuates oxidative stress and melanogenesis in B16F10 melanoma cells. Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.05.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Song YS, Balcos MC, Yun HY, Baek KJ, Kwon NS, Kim MK, Kim DS. ERK Activation by Fucoidan Leads to Inhibition of Melanogenesis in Mel-Ab Cells. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2014; 19:29-34. [PMID: 25605994 PMCID: PMC4297759 DOI: 10.4196/kjpp.2015.19.1.29] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 11/17/2014] [Accepted: 12/01/2014] [Indexed: 11/15/2022]
Abstract
Fucoidan, a fucose-rich sulfated polysaccharide derived from brown seaweed in the class Phaeophyceae, has been widely studied for its possible health benefits. However, the potential of fucoidan as a possible treatment for hyperpigmentation is not fully understood. This study investigated the effects of fucoidan on melanogenesis and related signaling pathways using Mel-Ab cells. Fucoidan significantly decreased melanin content. While fucoidan treatment decreased tyrosinase activity, it did not do so directly. Western blot analysis indicated that fucoidan downregulated microphthalmia-associated transcription factor and reduced tyrosinase protein expression. Further investigation showed that fucoidan activated the extracellular signal-regulated kinase (ERK) pathway, suggesting a possible mechanism for the inhibition of melanin synthesis. Treatment with PD98059, a specific ERK inhibitor, resulted in the recovery of melanin production. Taken together, these findings suggest that fucoidan inhibits melanogenesis via ERK phosphorylation.
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Affiliation(s)
- Yu Seok Song
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea. ; Department of Convergence Medicine and Pharmaceutical Biosciences, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Marie Carmel Balcos
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Hye-Young Yun
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Kwang Jin Baek
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Nyoun Soo Kwon
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Myo-Kyoung Kim
- Thomas J. Long School of Pharmacy, University of the Pacific, Stockton, CA 95211, USA
| | - Dong-Seok Kim
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
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Li H, Kim J, Hahn HG, Yun J, Jeong HS, Yun HY, Baek KJ, Kwon NS, Min YS, Park KC, Kim DS. KHG26792 Inhibits Melanin Synthesis in Mel-Ab Cells and a Skin Equivalent Model. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2014; 18:249-54. [PMID: 24976765 PMCID: PMC4071178 DOI: 10.4196/kjpp.2014.18.3.249] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 03/12/2014] [Accepted: 03/14/2014] [Indexed: 01/05/2023]
Abstract
The purpose of this study is to characterize the effects of KHG26792 (3-(naphthalen-2-yl(propoxy) methyl)azetidine hydrochloride), a potential skin whitening agent, on melanin synthesis and identify the underlying mechanism of action. Our data showed that KHG26792 significantly reduced melanin synthesis in a dose-dependent manner. Additionally, KHG26792 downregulated microphthalmia-associated transcription factor (MITF) and tyrosinase, the rate-limiting enzyme in melanogenesis, although tyrosinase was not inhibited directly. KHG26792 activated extracellular signal-regulated kinase (ERK), whereas an ERK pathway inhibitor, PD98059, rescued KHG26792-induced hypopigmentation. These results suggest that KHG26792 decreases melanin production via ERK activation. Moreover, the hypopigmentary effects of KHG26792 were confirmed in a pigmented skin equivalent model using Cervi cornus Colla (deer antler glue), in which the color of the pigmented artificial skin became lighter after treatment with KHG26792. In summary, our findings suggest that KHG26792 is a novel skin whitening agent.
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Affiliation(s)
- Hailan Li
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Jandi Kim
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Hoh-Gyu Hahn
- Organic Chemistry Laboratory, Korea Institute of Science & Technology, Seoul 136-791, Korea
| | - Jun Yun
- Organic Chemistry Laboratory, Korea Institute of Science & Technology, Seoul 136-791, Korea
| | - Hyo-Soon Jeong
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Hye-Young Yun
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Kwang Jin Baek
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Nyoun Soo Kwon
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
| | - Young Sil Min
- Department of Herb Industry, Jungwon University, Goesan 367-805, Korea
| | - Kyoung-Chan Park
- Department of Dermatology, Seoul National University Bundang Hospital, Seongnam 463-707, Korea
| | - Dong-Seok Kim
- Department of Biochemistry, Chung-Ang University College of Medicine, Seoul 156-756, Korea
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