DOCSLIB.ORG

Upregulation of Mitf by Phenolic Compounds-Rich Cymbopogon Schoenanthus Treatment Promotes Melanogenesis in B16 Melanoma Cells and Human Epidermal Melanocytes

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Upregulation of Mitf by Phenolic Compounds-Rich Cymbopogon Schoenanthus Treatment Promotes Melanogenesis in B16 Melanoma Cells and Human Epidermal Melanocytes Hindawi BioMed Research International Volume 2017, Article ID 8303671, 11 pages https://doi.org/10.1155/2017/8303671 Research Article Upregulation of Mitf by Phenolic Compounds-Rich Cymbopogon schoenanthus Treatment Promotes Melanogenesis in B16 Melanoma Cells and Human Epidermal Melanocytes Myra O. Villareal,1,2 Sayuri Kume,3 Mohamed Neffati,4 and Hiroko Isoda1,2 1 Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba City 305-8572, Japan 2Alliance for Research on North Africa (ARENA), University of Tsukuba, Tsukuba City 305-8572, Japan 3School of Life and Environmental Sciences, University of Tsukuba, Tsukuba City 305-8572, Japan 4The Institute of Arid Region (IRA), Medenine, Tunisia Correspondence should be addressed to Hiroko Isoda; [email protected] Received 6 September 2017; Accepted 17 October 2017; Published 21 November 2017 Academic Editor: Yunfeng Zhao Copyright © 2017 Myra O. Villareal et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Melanin provides inherent protection against skin cancer by absorbing broad-spectrum radiant energy of UV radiation. Cutaneous malignant melanoma incidence has recently been observed to increase and the frequency is closely associated with the skin color, highlighting the importance of skin pigmentation. Here, we showed how melanin biosynthesis is enhanced by treatment with phenolic compounds-rich Cymbopogon schoenanthus (CYM) in B16 murine melanoma cells and human epidermal melanocytes (HEM). CYM increased the melanin content of the cells by upregulating the expression of tyrosinase (TYR), tyrosinase-related protein 1 (TRP1), and dopachrome tautomerase (DCT) at the protein and mRNA levels, comparable to the effect of -melanocyte- stimulating hormone (MSH), in both B16 cells and HEM. Moreover, global gene expression analysis showed that at least 44 pigmentation-associated genes were modulated, including the microphthalmia-associated transcription factor (Mitf) and its transcriptional regulators (Sox10, Pax3,andLef1). Upregulation of copper transport-associated gene Atp7b indicates that CYM also promotes tyrosinase activity. CYM upregulated Mitf and possibly activates tyrosinase enzyme, providing evidence for its possible use to promote melanogenesis and as a therapeutic agent against hypopigmentation disorders. 1. Introduction against skin cancer by 500–1000-fold [4, 5]. Melanocytes, which contain specialized organelles called melanosomes, Skin pigmentation is our first line of defense against the produce the pigment melanin. Melanins are strong light harmful UV radiation, which is considered as one of the scatterers with a broad UV-visible absorption spectrum, major risk factors for melanoma skin cancer. Annually, providing protection not just to melanocytes but also to 132,000 individuals are diagnosed with melanoma, and it keratinocytes and other cells in the epidermis against UV is believed that as the ozone layers are depleted, more UV radiation-induced damage (photoproducts and oxidative radiation from the sun reaches the earth and will increase stress). Melanin can absorb a portion of the UV energy the incidence of skin cancers [1]. Moreover, the increase in and transform it into heat that is dissipated into the body sunburn and the use of tanning beds have been reported to be [6, 7]. Melanin biosynthesis occurs through an oxidation in an alarming situation now and contribute to the increase process, starting with the amino acid L-tyrosine, with the in the risk of cutaneous melanoma, especially in young rate-limiting enzyme tyrosinase (TYR), catalyzing three dis- individuals and in predominately fair-skinned populations tinct reactions: hydroxylation of L-tyrosine, dehydrogenation [2, 3]. The amount of melanin produced by melanocytes is of L-DOPA, and dehydrogenation of DHI, with L-DOPA considered to be the most useful predictor of risk for skin as the cofactor in the first and third reactions [4, 8, 9]. cancer so that highly pigmented skin provides protection Other reactions are mediated by tyrosinase-related protein 2 BioMed Research International (TRP1) and dopachrome tautomerase (DCT) that catalyze the and identified at the Ecology Laboratory, Institut des Regions tautomerization of indolene-2-carboxylic acid-5, 6-quinone Arides (IRA), Tunisia, while voucher specimens of the leaf or dopachrome and oxidation of 5,6-dihydroxylindole-2- samples (UT-ARENA-00709) were deposited in the Alliance carboxylic acid, respectively [10]. The expression of the forResearchonNorthAfrica,UniversityofTsukuba,Japan. melanogenic enzymes Tyr, Trp1,andDct is regulated by Extract of C. schoenanthus (CYM) was prepared as previously the helix-loop-helix transcription factor microphthalmia- reported[13].Briefly,10gofleavesofair-driedC.schoenan- associated transcription factor (Mitf). thus was macerated in 100 ml 70% ethanol and kept for two Recent researches focus on the regulation of pigmen- weeks at room temperature. The liquid fraction was then tation at the molecular level to promote melanogenesis as collected and, prior to use, was filtered using a 0.22 mfilter ∘ a possible therapeutic strategy against UV-induced DNA (Millipore, USA) and stored at −80 C. As a reference or 4 7 damage and skin cancer. Since individuals with lighter skin positive control, 400 nm -MSH or [Nle ,D-Phe]-D-Phel, color are more likely to develop skin cancer than those with melanocyte-stimulating hormone trifluoroacetate salt≥ ( 95% darker skin color [11], increasing skin pigmentation using purity) purchased from Sigma was used. materials considered to be safe for use can therefore be considered as the best strategy to provide protection against UV or to attain darker skin color without resorting to use of 2.3. Cell Proliferation Assay. The effect of CYM on B16 cells skin cancer-inducing tanning beds. proliferation was assessed using the 3-(4,5-dimethylthiazol- Recently, the acceptance into mainstream medicine of 2-yl)-2,5-diphenyl tetrazolium bromide or MTT assay × 4 mixtures of combination of plant natural products that may (Dojindo, Japan). B16 cells (3 10 cells/well) were seeded affect multiple pharmacological targets beyond the reach onto 96-well plates and cultured as described above. After of single-compound-based drugs has been suggested [12]. 24 h of incubation, the medium was replaced with a fresh We have previously reported that ethanol extract of Cymbo- medium with or without the sample at various concentra- pogon schoenanthus (CYM) provides beneficial effect against tions. MTT (5 mg/ml) was then added; the plates covered stress in ICR mice subjected to forced swimming and tail with aluminum foil and were incubated further for 28 h. Sodium dodecyl sulphate (SDS; 10%) was then added at 100 l suspension tests and the effect was attributed to its major ∘ components quercetin-3-rhamnoside, trans-cinnamic acid, per well and incubated overnight at 37 Ctodissolvethe resorcinol, caffeic acid, 2.5-dihydroxybenzoic acid, ferulic formazan completely. Absorbances were obtained at 570 nm acid, and gallic acid [13]. In pigment cells, oxidative stress using a microplate reader (Powerscan HT; Dainippon Phar- causes a downregulation of the melanogenic enzymes TYR, maceuticals USA Corp., NJ, USA). To correct the absorb- TRP1, and DCT and their transcription factor MITF, leading ances, blanks containing only medium MTT and SDS were to decreased melanin biosynthesis [14, 15]. And although the used. anti-stress effect of CYM has been tested, its effect on melano- genesis has not yet been determined. Therefore it is of major 2.4. Melanin Assay. B16cellswereculturedatadensityof5× 5 interest to characterize how CYM can regulate pigment cell 10 cells per 100-mm Petri dish. After overnight incubation, function and identify the molecular mechanism underlying the culture medium was replaced with DMEM medium its effect. In this study, the effect of CYM on melanogenesis in containing either 400 nM -MSH or different dilutions of B16 cells and human epidermal melanocytes was evaluated. C. schoenanthus ethanol extract. Cells were treated with - MSH served as positive control. After incubation for 48 h, 2. Materials and Methods the medium was then removed and the cells were washed 2.1. Cell Lines and Cell Culture. Murine B16F10 melanoma twice with phosphate-buffered saline (PBS) and harvested by cells or B16 cells (Cell No. RCB2630) used in this study trypsinization (0.25% trypsin/0.02% EDTA in PBS; Sigma). were obtained from the Riken Cell Bank (Tsukuba, Japan) The harvested cells were pelleted and solubilized using 0.1% and maintained in Dulbecco’s modified Eagle’s medium Triton X-100 and then purified by precipitation in 10% trichloroacetic acid. The isolated melanin was then dissolved (Nissui, Tokyo, Japan) supplemented with 10% fetal bovine ∘ serum (Sigma, St. Louis, MO, USA), 4 mM L-glutamine in8mNaOH,followedbyincubationfor2hat80C. (Sigma), 50 units/mL penicillin, and 50 g/mL streptomycin The amount of melanin in the solution was determined ∘ (Cambrex, East Rutherford, NJ, USA) and incubated at 37 C spectrophotometrically at 410 nm. The total melanin content was estimated using the standard curve for synthetic melanin in a humidified atmosphere of 5%2 CO . Human epidermal melanocytes (HEM) were obtained from Cell Applications, and expressed on a per viable cell basis and as percentage Inc. (San Diego, CA, USA) (Cat. No. 104K-05a),
Load more

Recommended publications
  • Genetic Variations in the PSMA6 and PSMC6 Proteasome Genes Are Associated with Multiple Sclerosis and Response to Interferon‑Β Therapy in Latvians
    EXPERIMENTAL AND THERAPEUTIC MEDICINE 21: 478, 2021 Genetic variations in the PSMA6 and PSMC6 proteasome genes are associated with multiple sclerosis and response to interferon‑β therapy in Latvians NATALIA PARAMONOVA1, JOLANTA KALNINA1, KRISTINE DOKANE1, KRISTINE DISLERE1, ILVA TRAPINA1, TATJANA SJAKSTE1 and NIKOLAJS SJAKSTE1,2 1Genomics and Bioinformatics, Institute of Biology of The University of Latvia; 2Department of Medical Biochemistry of The University of Latvia, LV‑1004 Riga, Latvia Received July 8, 2020; Accepted December 8, 2020 DOI: 10.3892/etm.2021.9909 Abstract. Several polymorphisms in genes related to the Introduction ubiquitin‑proteasome system exhibit an association with pathogenesis and prognosis of various human autoimmune Multiple sclerosis (MS) is a lifelong demyelinating disease of diseases. Our previous study reported the association the central nervous system. The clinical onset of MS tends to between multiple sclerosis (MS) and the PSMA3‑rs2348071 be between the second and fourth decade of life. Similarly to polymorphism in the Latvian population. The current study other autoimmune diseases, women are affected 3‑4 times more aimed to evaluate the PSMA6 and PSMC6 genetic variations, frequently than men (1). About 10% of MS patients experience their interaction between each other and with the rs2348071, a primary progressive MS form characterized by the progres‑ on the susceptibility to MS risk and response to therapy in sion of neurological disability from the onset. In about 90% the Latvian population. PSMA6‑rs2277460, ‑rs1048990 and of MS patients, the disease undergoes the relapse‑remitting PSMC6‑rs2295826, ‑rs2295827 were genotyped in the MS MS course (RRMS); in most of these patients, the condition case/control study and analysed in terms of genotype‑protein acquires secondary progressive course (SPMS) (2).
    [Show full text]
  • Microarray Analysis of Novel Genes Involved in HSV- 2 Infection
    Microarray analysis of novel genes involved in HSV- 2 infection Hao Zhang Nanjing University of Chinese Medicine Tao Liu ( [email protected] ) Nanjing University of Chinese Medicine https://orcid.org/0000-0002-7654-2995 Research Article Keywords: HSV-2 infection,Microarray analysis,Histospecic gene expression Posted Date: May 12th, 2021 DOI: https://doi.org/10.21203/rs.3.rs-517057/v1 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Page 1/19 Abstract Background: Herpes simplex virus type 2 infects the body and becomes an incurable and recurring disease. The pathogenesis of HSV-2 infection is not completely clear. Methods: We analyze the GSE18527 dataset in the GEO database in this paper to obtain distinctively displayed genes(DDGs)in the total sequential RNA of the biopsies of normal and lesioned skin groups, healed skin and lesioned skin groups of genital herpes patients, respectively.The related data of 3 cases of normal skin group, 4 cases of lesioned group and 6 cases of healed group were analyzed.The histospecic gene analysis , functional enrichment and protein interaction network analysis of the differential genes were also performed, and the critical components were selected. Results: 40 up-regulated genes and 43 down-regulated genes were isolated by differential performance assay. Histospecic gene analysis of DDGs suggested that the most abundant system for gene expression was the skin, immune system and the nervous system.Through the construction of core gene combinations, protein interaction network analysis and selection of histospecic distribution genes, 17 associated genes were selected CXCL10,MX1,ISG15,IFIT1,IFIT3,IFIT2,OASL,ISG20,RSAD2,GBP1,IFI44L,DDX58,USP18,CXCL11,GBP5,GBP4 and CXCL9.The above genes are mainly located in the skin, immune system, nervous system and reproductive system.
    [Show full text]
  • Interspecies Difference in the Regulation of Melanocyte Development by SOX10 and MITF
    Interspecies difference in the regulation of melanocyte development by SOX10 and MITF Ling Hou*†, Heinz Arnheiter‡, and William J. Pavan*† *Genetic Disease Research Branch, National Human Genome Research Institute, and ‡Mammalian Development Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892-4472 Communicated by Francis S. Collins, National Institutes of Health, Bethesda, MD, April 17, 2006 (received for review March 10, 2006) There is increasing indication that interspecific phenotypic differ- gous for a targeted mutation in Sox10 (12). In humans, SOX10 ences result from variations in gene-regulatory interactions. Here mutations are associated with Waardenburg–Hirschsprung dis- we provide evidence that mice differ from zebrafish in the way ease [Online Mendelian Inheritance in Man (OMIM) accession they use homologous key components to regulate pigment cell no. 277580] (13) and a complex neurocristopathy that combines differentiation. In both zebrafish and mice, one transcription peripheral demyelinating neuropathy, central leukodystrophy, factor, SOX10, controls the expression of another, MITF (microph- Waardenburg syndrome, and Hirschprung disease (PCWH, thalmia-associated transcription factor), which in turn regulates a OMIM accession no. 609136) (14). MITF, on the other hand, is set of genes critical for pigment cell development and pigmenta- a basic helix–loop–helix leucine zipper transcription factor tion. Mutations in either Sox10 or Mitf impair pigment cell devel- whose mutations lead to pigmentary abnormalities and, depend- opment. In Sox10-mutant zebrafish, experimentally induced ex- ing on the species, deafness and eye abnormalities but none of pression of Mitf fully rescues pigmentation. Using lineage-directed the intestinal or demyelinating and dysmyelinating symptoms gene transfer, we show that, in the mouse, Mitf can rescue seen with Sox10 mutations (6, 15).
    [Show full text]
  • The Role of DCT/TYRP2 in Resistance of Melanoma Cells to Drugs and Radiation
    Chapter 32 / DOPAchrome Tautomerase-Mediated Drug and Radiation Resistance 577 32 The Role of DCT/TYRP2 in Resistance of Melanoma Cells to Drugs and Radiation Brian J. Pak and Yaacov Ben-David CONTENTS INTRODUCTION RETROVIRAL INSERTIONAL MUTAGENESIS AS A METHOD OF GENERATING RESISTANT CELL LINES IDENTIFICATION OF DOPACHROME TAUTOMERASE AS A MEDIATOR OF DRUG RESISTANCE MELANOGENESIS AND TYROSINASE-RELATED PROTEINS EXPRESSION OF DCT DCT AND RADIATION RESISTANCE DCT AND IMMUNOTHERAPY OF HUMAN MELANOMA POSSIBLE MECHANISMS OF DCT-MEDIATED RESISTANCE STRESS-DEPENDENT MECHANISMS OF RESISTANCE IN MELANOMAS CONCLUSIONS AND PERSPECTIVES REFERENCES Summary Intrinsic resistance to both chemotherapy and radiotherapy remains a major obstacle in the clinical treatment of malignant melanoma. Recent advances in cancer research have provided new insights into the molecular mechanisms governing their intrinsic resistance. We have recently demonstrated that DOPAchrome tautomerase (DCT), an enzyme that is well characterized for its function in melanin syn- thesis, is highly expressed in human melanoma cells that are resistant to both drug and radiation treat- ments. Conversely, melanoma cells expressing very low levels of DCT are highly susceptible to either type of treatment. Overexpression of DCT in melanoma cells by transfection could confer both radiore- sistance and chemoresistance. This review will summarize our findings, as well as discuss the possible mechanisms by which DCT overexpression contributes to intrinsic resistance of human malignant mela- noma. Key Words: Radioresistance; chemoresistance; malignant melanoma; DOPAchrome tauto- merase (DCT). From: From Melanocytes to Melanoma: The Progression to Malignancy Edited by: V. J. Hearing and S. P. L. Leong © Humana Press Inc., Totowa, NJ 577 578 From Melanocytes to Melanoma INTRODUCTION Conventional cancer therapies involve the selective targeting of actively dividing cells by either the systemic administration of antineoplastic agents or localized treatment with ionizing radiation.
    [Show full text]
  • Review Genetics of Pigment Cells: Lessons from the Tyrosinase Gene
    Histol Histopathol (2006) 21: 567-578 Histology and http://www.hh.um.es Histopathology Cellular and Molecular Biology Review Genetics of pigment cells: lessons from the tyrosinase gene family F. Murisier and F. Beermann ISREC (Swiss Institute for Experimental Cancer Research), National Center of Competence in Research (NCCR) Molecular Oncology, Epalinges, Switzerland Summary. In mammals, the melanin pigment is Introduction produced in two cell types of distinct developmental origins. The melanocytes of the skin originate form the The coat color phenotypes have been studied for neural crest whereas the retinal pigment epithelium more than one century leading to the establishment of (RPE) of the eye originates from the optic cup. The some of the first rodent inbred strains (Morse, 1978). genetic programs governing these two cell types are thus The mouse strain DBA selected for the dilute, brown and quite different but have evolved to allow the expression non-agouti coat color alleles was already established in of pigment cell-specific genes such as the three members 1909 by Little (Beck et al., 2000). An albino strain was of the tyrosinase-related family. Tyrosinase, Tyrp1 and used to first demonstrate Mendelian inheritance of a Dct promoters contain a motif termed E-box which is genetic trait in mammals in 1903 (Castle and Allen, bound by the transcription factor Mitf. These E-boxes 1903; Beermann et al., 2004). Thus, pigment genes were are also found in the promoters of the corresponding fish “pioneers” for the exploration of mouse genetics leading genes, thus highlighting the pivotal role of Mitf in to the discovery of 127 separate loci with 63 genes pigment cell-specific gene regulation.
    [Show full text]
  • Associated Transcription Factor and the BRG1‐Containing SWI/SNF Complex During Melanocyte Differentiation
    Received: 5 February 2018 | Accepted: 7 November 2018 DOI: 10.1002/jcp.27840 ORIGINAL RESEARCH ARTICLE BAF60A mediates interactions between the microphthalmia- associated transcription factor and the BRG1‐containing SWI/SNF complex during melanocyte differentiation Shweta Aras1,2 | Srinivas Vinod Saladi1,3 | Tupa Basuroy1 | Himangi G. Marathe1,4 | Patrick Lorès5 | Ivana L. de la Serna1 1Department of Cancer Biology, University of Toledo College of Medicine and Life Sciences, Abstract Toledo, Ohio SWI/SNF chromatin remodeling enzymes are multisubunit complexes that contain 2Department of Cancer Biology, University of one of two catalytic subunits, BRG1 or BRM and 9–11 additional subunits called Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, BRG1 or BRM‐associated factors (BAFs). BRG1 interacts with the microphthalmia‐ 3Department of Otolaryngology, associated transcription factor (MITF) and is required for melanocyte development in Massachusetts Eye and Ear Infirmary, Massachusetts General Hospital Cancer vitro and in vivo. The subunits of SWI/SNF that mediate interactions between BRG1 Center, Harvard Medical School, Boston, and MITF have not been elucidated. Three mutually exclusive isoforms of a 60‐kDa Massachusetts subunit (BAF60A, B, or C) often facilitate interactions with transcription factors 4Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, during lineage specification. We tested the hypothesis that a BAF60 subunit Buffalo, New York promotes interactions between MITF and the BRG1‐containing SWI/SNF complex. 5INSERM U1016, Institut Cochin/CNRS UMR8104/ Universite Paris Descartes, We found that MITF can physically interact with BAF60A, BAF60B, and BAF60C. The Faculte de Medecine Cochin, Paris, France interaction between MITF and BAF60A required the basic helix‐loop‐helix domain of Correspondence MITF.
    [Show full text]
  • 12.2% 130,000 155M Top 1% 154 5,300
    We are IntechOpen, the world’s leading publisher of Open Access books Built by scientists, for scientists 5,300 130,000 155M Open access books available International authors and editors Downloads Our authors are among the 154 TOP 1% 12.2% Countries delivered to most cited scientists Contributors from top 500 universities Selection of our books indexed in the Book Citation Index in Web of Science™ Core Collection (BKCI) Interested in publishing with us? Contact [email protected] Numbers displayed above are based on latest data collected. For more information visit www.intechopen.com Chapter 3 The Multiple Roles of Tyrosinase-Related Protein-2/L- The Multiple Roles of Tyrosinase-Related Protein-2/L- Dopachrome Tautomerase in Melanoma: Biomarker, Therapeutic Target, and Molecular Driver in Tumor Progression Adina L. Milac and Gabriela Negroiu AdinaAdditional L. information Milac and is availableGabriela at the Negroiu end of the chapter Additional information is available at the end of the chapter http://dx.doi.org/10.5772/intechopen.70513 Abstract Cutaneous malignant melanoma (CMM), which is ranked as the 8th most common can- cers in the US, makes 4–7% of skin cancers but it causes approximately 80% of skin cancer deaths. CMM is characterized by insidious and fast progression, heterogenic evo- lution, and significant resistance to numerous therapeutic strategies. CMM is the result of the uncontrolled proliferation of melanocytes, the cells which reside in the basal layer of the epidermis. The most efficient therapy is the surgical removal if the lesion is in an early stage. For metastatic melanomas, there are different strategies, extremely rarely leading to total cure.
    [Show full text]
  • Identification of Potential Hub Genes Associated with Skin Wound Healing
    Zhu et al. BMC Surg (2021) 21:303 https://doi.org/10.1186/s12893-021-01298-w RESEARCH ARTICLE Open Access Identifcation of potential hub genes associated with skin wound healing based on time course bioinformatic analyses Hai‑jun Zhu, Meng Fan and Wei Gao* Abstract Background: The skin is the largest organ of the body and has multiple functions. Wounds remain a signifcant healthcare problem due to the large number of traumatic and pathophysiological conditions patients sufer. Methods: Gene expression profles of 37 biopsies collected from patients undergoing split‑thickness skin grafts at fve diferent time points were downloaded from two datasets (GSE28914 and GSE50425) in the Gene Expression Omnibus (GEO) database. Principal component analysis (PCA) was applied to classify samples into diferent phases. Subsequently, diferentially expressed genes (DEGs) analysis, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway functional enrichment analyses were performed, and protein–protein interaction (PPI) networks created for each phase. Furthermore, based on the results of the PPI, hub genes in each phase were identi‑ fed by molecular complex detection combined with the ClueGO algorithm. Results: Using principal component analysis, the collected samples were divided into four phases, namely intact phase, acute wound phase, infammatory and proliferation phase, and remodeling phase. Intact samples were used as control group. In the acute wound phase, a total of 1 upregulated and 100 downregulated DEGs were identifed. Tyrosinase (TYR), tyrosinase Related Protein 1 (TYRP1) and dopachrome tautomerase (DCT) were considered as hub genes and enriched in tyrosine metabolism which dominate the process of melanogenesis. In the infammatory and proliferation phase, a total of 85 upregulated and 164 downregulated DEGs were identifed.
    [Show full text]
  • Post-Transcriptional Regulation of Melanin Biosynthetic Enzymes by Camp and Resveratrol in Human Melanocytes Richard A
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector ORIGINAL ARTICLE Post-Transcriptional Regulation of Melanin Biosynthetic Enzymes by cAMP and Resveratrol in Human Melanocytes Richard A. Newton1, Anthony L. Cook1, Donald W. Roberts1,2, J. Helen Leonard2 and Richard A. Sturm1 Upregulation of microphthalmia-associated transcription factor (MITF) expression has been proposed to mediate melanogenesis stimulated by cAMP, whereas downregulation of MITF has been suggested to underlie the depigmentary effects of resveratrol, a promising chemotherapeutic found in red wine. We have assessed the contribution of MITF to pigmentation regulation by treating primary cultures of normal human melanocytes with the adenylate cyclase activator forskolin and/or resveratrol, then quantifying mRNA and protein levels for MITF, tyrosinase, tyrosinase-related protein-1, and dopachrome tautomerase (DCT). The inhibition of tyrosinase activity by resveratrol was not due to alterations in MITF, but instead was explained by both direct tyrosinase inhibition and a post-transcriptional effect that reduced the amount of fully processed tyrosinase. Glycosidase digestion revealed that the basis for the tyrosinase decrease was the retention of an immature form in the ER and subsequent loss of the mature, Golgi-processed enzyme. Elevation of intracellular cAMP by forskolin markedly increased protein levels for MITF, tyrosinase and DCT, however there was no concomitant increase in tyrosinase or DCT mRNA. This indicated that elevated levels of MITF were not sufficient to promote transcription of these melanogenic genes and that the increase in their protein abundance appeared to be predominantly mediated through post-transcriptional processing events.
    [Show full text]
  • Melanocytes and the Transcription Factor Sox10
    Chapter 4 / Melanocytes and Sox10 71 4 Melanocytes and the Transcription Factor Sox10 Michael Wegner CONTENTS INTRODUCTION SOX10 AND MELANOCYTES SOX10 AND MITF EXPRESSION MOLECULAR SOX10 FUNCTION CONCLUSIONS AND PERSPECTIVES REFERENCES Summary The high-mobility group (HMG) domain transcription factor Sox10 influences melanocyte develop- ment on at least two levels. Sox10 is required for survival, proliferation, and the maintenance of pluripo- tent neural crest stem cells, thereby controlling the size of the stem cell pool and indirectly influencing the number of generated melanocytes. Sox10 also directly affects melanocyte specification. Expression of Mitf, the key regulator of melanocyte development, is controlled by Sox10, which binds to and acti- vates the M promoter of the Mitf gene in close cooperation with other signaling pathways. Although its epistatic relationship to Mitf is sufficient to explain the role of Sox10 in melanocyte specification, analy- ses of expression and target genes suggest that Sox10 has additional functions in melanocytes apart from and following Mitf activation. Additionally, Sox10 is highly expressed in melanoma. It may influence melanoma properties and could therefore be of diagnostic and therapeutic value. Key Words: Sry-box; HMG; neural crest; Mitf; synergy; Pax3; Waardenburg disease; dopachrome tautomerase; tyrosinase-related protein 2; E-catenin. INTRODUCTION Transcription factors play vital roles in the development of most cell types, tissues, and organs. Sox proteins are one such group of transcription factors. They are charac- terized by possession of a common DNA-binding domain, the Sry-box (1,2) that was first identified in Sry, a protein encoded on the mammalian Y chromosome and responsible for male sex determination (3,4).
    [Show full text]
  • Microphthalmia-Associated Transcription Factor (MITF) – from Waardenburg Syndrome Genetics to Melanoma Therapy
    Review article Microphthalmia-associated transcription factor (MITF) – from Waardenburg syndrome genetics to melanoma therapy Ivan Šamija, Josip Lukač, Zvonko Kusić Department of Oncology and Nuclear Medicine, Microphthalmia-associated transcription factor (MITF) was University Hospital “Sestre milosrdnice”, first discovered as protein coded by gene whose mutations Zagreb, Croatia are associated with Waardenburg syndrome. Later, MITF was shown to be key transcription factor regulating melanogen- esis. Further studies have shown that in addition to regulat- ing melanogenesis MITF also plays central role in regulation Corresponding author: of melanocyte development and survival. MITF gene is am- Ivan Šamija plified in a proportion of melanomas and ectopic MITF ex- Department of oncology and Nuclear Medicine pression can transform melanocytes so MITF can function University Hospital “Sestre milosrdnice” as melanoma “lineage survival” oncogene. Different studies Vinogradska cesta 29 have further revealed MITF’s important but complex role in 10000 Zagreb tumorigenesis and progression of melanoma. As expected Croatia from its important role in melanocytes and melanoma MITF [email protected] is intricately regulated on all the levels from transcription to Tel.: + 385 1 3787647 post-translational modifications. Although complex mecha- nisms of MITF functioning are still being revealed, MITF already has a valuable role in managing melanoma patients. Immunohistochemical analysis of MITF has shown both di- agnostic and prognostic value in patients with melanoma. MITF is also a valuable specific marker for detection of circu- lating melanoma cells by reverse-transcription – polymerase chain reaction. MITF has recently been investigated as a po- tential target for melanoma therapy. Key words: Microphthalmia-associated transcription fac- Received: 28 September 2010 tor, Melanoma, Melanocytes, Biological tumor markers, Accepted: 31 October 2010 Waardenburg’s syndrome.
    [Show full text]
  • 81928419.Pdf
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE providedORIGINAL by Elsevier - ARTICLE Publisher Connector See related Commentary on pages 1215 and 1218 Modulation of Microphthalmia-associated Transcription Factor Gene Expression Alters Skin Pigmentation C. B. Lin,L. Babiarz,F. Liebel,E. Roydon Price, n M. Kizoulis,G. J. Gendimenico,D. E. Fisher, n and M. Seiberg Johnson & Johnson Skin Research Center,CPWW,Skillman,NJ 08558,U.S.A.; nDepartment of Pediatric Hematology/Oncology,Dana Farber Cancer Research Institute and Harvard Medical School,Boston,MA 02115,U.S.A. The microphthalmia-associated transcription factor is reduced microphthalmia-associated transcription factor implicated in melanocyte development and in the reg- and tyrosinase promoter activities. These agents also in- ulation of melanogenesis. Microphthalmia-associated hibited the forskolin- and ultraviolet B-stimulated pro- transcription factor is thought to bind to the M-box moter activities of these genes and signi¢cantly reduced promoter elements of tyrosinase, tyrosinase-related tyrosinase activity in melanocyte cultures, resulting in protein-1 and dopachrome tautomerase/tyrosinase- depigmentation. Overexpressed microphthalmia-asso- related protein-2 and transactivate these genes, resulting ciated transcription factor was capable of rescuing the in increased pigmentation. Using a luciferase reporter repressive e¡ects of these compounds on the cotrans- construct driven by the microphthalmia-associated fected tyrosinase promoter. Dark-skinned Yucatan transcription factor promoter, we identi¢ed agents that swine treated with these agents showed visible skin modulate microphthalmia-associated transcription fac- lightening, which was con¢rmed histologically, whereas tor promoter activity. Changes in endogenous micro- ultraviolet B-induced tanning of light-skinned swine phthalmia-associated transcription factor expression was inhibited using these agents.
    [Show full text]