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Yang S, Wang Z, Hu Y, Zong K, Zhang X, Ke H, Wang P, Go Y, Chan XHF, Wu J, Huang Q. Hydrolyzed Conchiolin Protein (HCP) Extracted from Pearls Antagonizes both ET-1 and α-MSH for Skin Whitening. Int J Mol Sci 2023; 24:ijms24087471. [PMID: 37108635 PMCID: PMC10138581 DOI: 10.3390/ijms24087471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/11/2023] [Accepted: 04/13/2023] [Indexed: 04/29/2023] Open
Abstract
Pearl powder is a famous traditional Chinese medicine that has a long history in treating palpitations, insomnia, convulsions, epilepsy, ulcers, and skin lightining. Recently, several studies have demonstrated the effects of pearl extracts on protection of ultraviolet A (UVA) induced irritation on human skin fibroblasts and inhibition of melanin genesis on B16F10 mouse melanoma cells. To further explore the effect we focused on the whitening efficacy of pearl hydrolyzed conchiolin protein (HCP) on human melanoma MNT-1 cells under the irritation of alpha-melanocyte-stimulating hormone (α-MSH) or endothelin 1 (ET-1) to evaluate the intracellular tyrosinase and melanin contents, as well as the expression levels of tyrosinase (TYR), tyrosinase related protein 1 (TRP-1), and dopachrome tautomerase (DCT) genes and related proteins. We found that HCP could decrease the intracellular melanin content by reducing the activity of intracellular tyrosinase and inhibiting the expression of TYR, TRP-1, DCT genes and proteins. At the same time, the effect of HCP on melanosome transfer effect was also investigated in the co-culture system of immortalized human keratinocyte HaCaT cells with MNT-1. The result indicated that HCP could promote the transfer of melanosomes in MNT-1 melanocytes to HaCaT cells, which might accelerate the skin whitening process by quickly transferring and metabolizing melanosomes during keratinocyte differentiation. Further study is needed to explore the mechanism of melanosome transfer with depigmentation.
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Affiliation(s)
- Shan Yang
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
| | - Zhekun Wang
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
| | - Yunwei Hu
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
| | - Kaile Zong
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
| | - Xingjiang Zhang
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
| | - Hui Ke
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
| | - Pan Wang
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
| | - Yuyo Go
- Royal Victoria Hospital, 274 Grosvenor Rd, Belfast BT12 6BA, UK
| | | | - Jianxin Wu
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
| | - Qing Huang
- Skin Health and Cosmetic Development & Evaluation Laboratory, China Pharmaceutical University, Nanjing 211198, China
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2
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Goyer B, Pereira U, Magne B, Larouche D, Kearns-Turcotte S, Rochette PJ, Martin L, Germain L. Impact of ultraviolet radiation on dermal and epidermal DNA damage in a human pigmented bilayered skin substitute. J Tissue Eng Regen Med 2019; 13:2300-2311. [PMID: 31502756 DOI: 10.1002/term.2959] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 08/08/2019] [Accepted: 09/04/2019] [Indexed: 12/18/2022]
Abstract
Our laboratory has developed a scaffold-free cell-based method of tissue engineering to produce bilayered tissue-engineered skin substitutes (TESs) from epidermal and dermal cells. However, TES pigmentation is absent or heterogeneous after grafting, due to a suboptimal number of melanocytes in culture. Our objectives were to produce TESs with a sufficient quantity of melanocytes from different pigmentation phototypes (light and dark) to achieve a homogeneous color and to evaluate whether the resulting pigmentation was photoprotective against ultraviolet radiation (UVR)-induced DNA damage in the dermis and the epidermis. TESs were cultured using different concentrations of melanocytes (100, 200, and 1,500 melanocytes/mm2 ), and pigmentation was evaluated in vitro and after grafting onto an athymic mouse excisional model. Dermal and epidermal DNA damage was next studied, exposing pigmented TESs to 13 and 32.5 J/cm2 UVR in vitro. We observed that melanocyte cell density increased with culture time until reaching a plateau corresponding to the cell distribution of native skin. Pigmentation of melanocyte-containing TESs was similar to donor skin, with visible melanin transfer from melanocytes to keratinocytes. The amount of melanin in TESs was inversely correlated to the UVR-induced formation of cyclobutane pyrimidine dimer in dermal fibroblasts and keratinocytes. Our results indicate that the pigmentation conferred by the addition of melanocytes in TESs protects against UVR-induced DNA damage. Therefore, autologous pigmented TESs could ensure photoprotection after grafting.
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Affiliation(s)
- Benjamin Goyer
- Centre de recherche du CHU de Québec, Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Québec, QC, Canada
- Département de chirurgie, Faculté de médecine, Université Laval, Québec, QC, Canada
| | - Ulysse Pereira
- Centre de recherche du CHU de Québec, Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Québec, QC, Canada
- Département de chirurgie, Faculté de médecine, Université Laval, Québec, QC, Canada
| | - Brice Magne
- Centre de recherche du CHU de Québec, Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Québec, QC, Canada
- Département de chirurgie, Faculté de médecine, Université Laval, Québec, QC, Canada
| | - Danielle Larouche
- Centre de recherche du CHU de Québec, Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Québec, QC, Canada
- Département de chirurgie, Faculté de médecine, Université Laval, Québec, QC, Canada
| | - Sélia Kearns-Turcotte
- Centre de recherche du CHU de Québec, Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Québec, QC, Canada
- Département de chirurgie, Faculté de médecine, Université Laval, Québec, QC, Canada
| | - Patrick J Rochette
- Centre de recherche du CHU de Québec, Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Québec, QC, Canada
- Département d'ophtalmologie et d'oto-rhino-laryngologie - chirurgie cervico-faciale, Faculté de médecine, Université Laval, Québec, QC, Canada
| | - Ludovic Martin
- Service de Dermatologie, CHU d'Angers, et Institut MitoVasc (UMR INSERM 1083, UMR CNRS 6015), Université d'Angers, Angers, France
| | - Lucie Germain
- Centre de recherche du CHU de Québec, Université Laval and Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Québec, QC, Canada
- Département de chirurgie, Faculté de médecine, Université Laval, Québec, QC, Canada
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3
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Yuan XH, Jin ZH. Paracrine regulation of melanogenesis. Br J Dermatol 2018; 178:632-639. [PMID: 28494100 DOI: 10.1111/bjd.15651] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/05/2017] [Indexed: 01/10/2023]
Abstract
Melanocytes are generally characterized by the basic ability of melanin synthesis and transfer to adjacent keratinocytes. This constitutes an individual skin phenotype and provides epidermal protection from various stimuli, such as ultraviolet irradiation, through a complex process called melanogenesis, which can be regulated by autocrine or paracrine factors. Recent evidence has revealed the paracrine effects of keratinocytes on melanogenesis by secreting cytokines, including α-melanocyte stimulating hormone and endothelin-1. In addition to keratinocytes, there are other types of cells in the skin, such as fibroblasts and immune cells, which are also actively involved in the regulation of melanocyte behaviour through the production of paracrine factors. In addition, extracellular matrix proteins, which are secreted mainly by skin-resident cells, not only play direct roles in regulating melanocyte morphology and functions but also provide structural support between the epidermis and dermis to control the distribution of various secreted cytokines from keratinocytes and/or fibroblasts, which are potentially involved in the regulation of melanogenesis. Moreover, understanding the origin of melanocytes (neural crest cells) and the presence of nerve endings in the epidermis can reveal the intimate contact between melanocytes and cutaneous specific nervous system proteins. Melanocytes are associated with all these networks with corresponding receptors expressed on the cell surface. In this review, we provide an overview of recent advances in determining the intimate relationships between melanocytes and their surrounding elements, which provide insights into the complex nature of the regulation of melanogenesis.
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Affiliation(s)
- X H Yuan
- Department of Dermatology, Yanbian University Hospital, 1327 Juzi Street, Yanji City, Jilin Province, 133000, China
| | - Z H Jin
- Department of Dermatology, Yanbian University Hospital, 1327 Juzi Street, Yanji City, Jilin Province, 133000, China
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Ren H, Wang G, Jiang J, Li J, Fu L, Liu L, Li N, Zhao J, Sun X, Zhang L, Zhang H, Zhou P. Comparative transcriptome and histological analyses provide insights into the prenatal skin pigmentation in goat ( Capra hircus). Physiol Genomics 2017; 49:703-711. [PMID: 28972038 DOI: 10.1152/physiolgenomics.00072.2017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 08/31/2017] [Accepted: 09/29/2017] [Indexed: 11/22/2022] Open
Abstract
The Youzhou dark goat is a natural mutant with dark skin over the whole body including the visible mucous membranes. In the present study, we characterized 100-day-old fetal skin at the histomorphological and transcriptomic levels in dark-skinned (Youzhou dark goat) and white-skinned (Yudong white goat) goats with deep RNA sequencing, quantitative PCR, and histological methods. Histological analysis indicated that there were marked differences in both melanin distribution and epidermal ultrastructure between the hyperpigmented and normal skin in two breeds of goat. Subsequent analyses suggested that a presumed structure variation (duplication or insertion) in ASIP might be responsible for its lower expression in the hyperpigmented skin (Youzhou dark goat) by determining the distribution of melanocytes across the body at early development stage. Analyses for genes with differential expression between the dark-skinned and white-skinned goats indicated the network composed of ASIP-MC1R, ECM-receptor interaction, and MAPK signaling might play crucial roles in the determination of skin pigmentation in fetal goats. Moreover, we also identified 1,616 novel transcripts in goat skin by RNA sequencing, which may represent two distinct groups of transcript based on their characteristics. Our findings contribute to the understanding of the characteristics of global gene expression in early-stage skin pigmentation and development and describe an animal model for human diseases associated with pigmentation.
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Affiliation(s)
- Hangxing Ren
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
| | - Gaofu Wang
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
| | - Jing Jiang
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
| | - Jie Li
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
| | - Lin Fu
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
| | - Liangjia Liu
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
| | - Nianfu Li
- Youyang Animal Husbandry Bureau, Youyang, Chongqing, China
| | - Jinhong Zhao
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
| | - Xiaoyan Sun
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
| | - Li Zhang
- Youyang Animal Husbandry Bureau, Youyang, Chongqing, China
| | - Haiyan Zhang
- Youyang Animal Husbandry Bureau, Youyang, Chongqing, China
| | - Peng Zhou
- Chongqing Academy of Animal Sciences, Rongchang, Chongqing, China; and
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5
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Abdel-Naser MB, Seltmann H, Zouboulis CC. SZ95 sebocytes induce epidermal melanocyte dendricity and proliferation in vitro. Exp Dermatol 2012; 21:393-5. [DOI: 10.1111/j.1600-0625.2012.01468.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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6
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Shin YH, Seo YK, Yoon HH, Song KY, Park JK. Effect of keratinocytes on regulation of melanogenesis in culture of melanocytes. BIOTECHNOL BIOPROC E 2012. [DOI: 10.1007/s12257-011-0299-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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7
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Wang Z, Li X, Yang Z, He X, Tu J, Zhang T. Effects of aloesin on melanogenesis in pigmented skin equivalents. Int J Cosmet Sci 2008; 30:121-30. [DOI: 10.1111/j.1468-2494.2008.00432.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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8
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Roberts DW, Newton RA, Leonard JH, Sturm RA. Melanocytes expressing MC1R polymorphisms associated with red hair color have altered MSH-ligand activated pigmentary responses in coculture with keratinocytes. J Cell Physiol 2008; 215:344-55. [PMID: 17960564 DOI: 10.1002/jcp.21318] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The occurrence of red hair and pale skin in individuals, which is associated with UV-radiation sensitivity and increased skin cancer risk, is mainly due to polymorphisms in the melanocortin-1 receptor (MC1R) expressed in melanocytes. We have established a serum free human melanocyte-keratinocyte coculture system to study the behavior and functional abilities of melanocytes expressing MC1R red hair color (RHC) variants in order to identify differences from their wild type (WT) counterparts. This model revealed the importance of elevated calcium levels in promoting strong melanocyte interaction with the surrounding keratinocytes and resulted in a dendritic melanocyte morphology similar to that in skin. However, the dendricity response following agonist activation of the MC1R receptor by NDP-MSH peptide, was markedly enhanced in WT melanocytes in comparison to RHC strains. Analysis of mRNA expression and protein levels of the major pigmentation markers following NDP-MSH treatment distinguished the enzyme dopachrome tautomerase as preferentially upregulated in cocultures of WT strains, with negligible or a much reduced response in melanocytes with RHC variant alleles. These results highlight the use of the coculture system in determining fundamental differences in the physiology of melanocytes expressing RHC MC1R receptors and those of WT genotype, which are likely to contribute to the increased skin cancer risk for individuals that carry these variants.
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Affiliation(s)
- Donald W Roberts
- Melanogenix Group, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
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9
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Joshi PG, Nair N, Begum G, Joshi NB, Sinkar VP, Vora S. Melanocyte-keratinocyte interaction induces calcium signalling and melanin transfer to keratinocytes. ACTA ACUST UNITED AC 2007; 20:380-4. [PMID: 17850511 DOI: 10.1111/j.1600-0749.2007.00397.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Physical contact between melanocytes and keratinocytes is a prerequisite for melanosome transfer to occur, but cellular signals induced during or after contact are not fully understood. Herein, it is shown that interactions between melanocyte and keratinocyte plasma membranes induced a transient intracellular calcium signal in keratinocytes that was required for pigment transfer. This intracellular calcium signal occurred due to release of calcium from intracellular stores. Pigment transfer observed in melanocyte-keratinocyte co-cultures was inhibited when intracellular calcium in keratinocytes was chelated. We propose that a 'ligand-receptor' type interaction exists between melanocytes and keratinocytes that triggers intracellular calcium signalling in keratinocytes and mediates melanin transfer.
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Affiliation(s)
- Preeti G Joshi
- National Institute of Mental Health and Neurosciences, Department of Biophysics, Bangalore, India
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10
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Yoon TJ, Lei TC, Yamaguchi Y, Batzer J, Wolber R, Hearing VJ. Reconstituted 3-dimensional human skin of various ethnic origins as an in vitro model for studies of pigmentation. Anal Biochem 2003; 318:260-9. [PMID: 12814630 DOI: 10.1016/s0003-2697(03)00172-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Reconstituted 3-dimensional human skin equivalents containing melanocytes and keratinocytes on an artificial dermal substitute are gaining popularity for studies of skin metabolism because they exhibit morphological and growth characteristics similar to human epidermis. In this study, we show that such a pigmented epidermis model can be used to assess the regulation of pigmentation by known melanogenic compounds. In monolayers or in melanocyte-keratinocyte co-cultures, melanocyte-keratinocyte interactions are missing or are spatially limited. The commercial skin equivalents used in this study were derived from epidermal cells obtained from donors of three different ethnic origins (African- American, Asian, and Caucasian), and they reflect those distinct skin phenotypes. We used these pigmented human epidermis models to test compounds for potential effects on pigmentation in a more physiologically relevant context, which allows further characterization and validation of interesting melanogenic factors. We used known melanogenic stimulators (alpha-melanocyte-stimulating hormone and 3,4-dihydroxyphenylalanine) and inhibitors (hydroquinone, arbutin, kojic acid, and niacinamide) and examined their effects on the production of melanin and its distribution in upper layers of the skin. Our studies indicate that commercial skin equivalents provide a convenient and cost-effective alternative to animal testing for evaluating the regulation of mammalian pigmentation by melanogenic factors and for elucidating their mechanisms of action.
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Affiliation(s)
- Tae-Jin Yoon
- Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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11
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Yoon TJ, Hearing VJ. Co-culture of mouse epidermal cells for studies of pigmentation. PIGMENT CELL RESEARCH 2003; 16:159-63. [PMID: 12622793 DOI: 10.1034/j.1600-0749.2003.00028.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Interactions between melanocytes and keratinocytes in the skin suggest bi-directional interchanges between these two cell types. Thus, melanocytes cultured alone may not accurately reflect the physiology of the skin and the effects of physiological regulators in vivo, because they do not consider possible interactions with keratinocytes. As more and more pigment genes are identified and cloned, the characterization of their functions becomes more of a challenge, particularly with respect to their roles in the processing and transport of melanosomes and their transfer to keratinocytes. Immortalized melanocytes mutant at these loci are now being routinely generated from mice, but interestingly, successful co-culture of murine melanocytes and keratinocytes is very difficult compared with their human counterparts. Thus, we have now optimized co-culture conditions for murine melanocytes and keratinocytes so that pigmentation and the effects of specific mutations can be studied in a more physiologically relevant context.
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Affiliation(s)
- Tae-Jin Yoon
- Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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12
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Duval C, Smit NPM, Kolb AM, Régnier M, Pavel S, Schmidt R. Keratinocytes control the pheo/eumelanin ratio in cultured normal human melanocytes. PIGMENT CELL RESEARCH 2002; 15:440-6. [PMID: 12453186 DOI: 10.1034/j.1600-0749.2002.02055.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The pheo/eumelanin ratio of cultured normal human melanocytes is distinct from the ratio observed for the same cells in vivo where they are in close contact with keratinocytes. To study the possible involvement of keratinocytes in the control of melanogenesis, we compared quantitatively and qualitatively the melanin production in melanocyte mono-cultures, in melanocyte-keratinocyte co-cultures and in pigmented reconstructed epidermis. Pheomelanin and eumelanin contents were assessed by high-performance liquid chromatography with electrochemical and fluorometric detection of their specific degradation products and revealed striking differences in the presence of keratinocytes. In the absence of keratinocytes (melanocyte mono-cultures), we observed a very limited eumelanin production and a very high pheomelanin synthesis. The pheo/eumelanin ratio in mono-cultures could be slightly influenced by changing the composition of the culture medium, however, the very strong imbalance in favor of pheomelanin remained unchanged. An induction of eumelanin synthesis accompanied by an important reduction of pheomelanin formation was only observed in the presence of keratinocytes. The pheo/eumelanin ratio in melanocyte mono-culture dropped from 1043 down to about 25 in the presence of keratinocytes (co-cultures). The same observations were made when the melanocytes were integrated into a reconstructed human epidermis. Interestingly, under co-culture conditions resulting in only a partial contact between melanocytes and keratinocytes, the reduction of the pheo/eumelanin ratio were less pronounced. From these results we conclude that keratinocytes play an important role in the melanin production, affecting the melanogenic pathways.
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Hirobe T, Furuya R, Akiu S, Ifuku O, Fukuda M. Keratinocytes control the proliferation and differentiation of cultured epidermal melanocytes from ultraviolet radiation B-induced pigmented spots in the dorsal skin of hairless mice. PIGMENT CELL RESEARCH 2002; 15:391-9. [PMID: 12213097 DOI: 10.1034/j.1600-0749.2002.02052.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Long-term exposure of ultraviolet radiation B (UVB)-induced pigmented spots in the dorsal skin of hairless mice of Hos:(HR-1 X HR//De) F1. Previous study showed that the proliferative and differentiative activities of cultured epidermal melanoblasts/melanocytes from UVB-induced pigmented spots increased with the development of the pigmented spots. To determine whether the increase in the proliferative and differentiative activities of epidermal melanoblasts/melanocytes was brought about by direct changes in melanocytes, or by indirect changes in surrounding keratinocytes, pure cultured melanoblasts/melanocytes and keratinocytes were prepared and co-cultured in combination with control and irradiated mice in a serum-free culture medium. Keratinocytes from irradiated mice stimulated the proliferation and differentiation of both neonatal and adult non-irradiated melanoblasts/melanocytes more greatly than those from non-irradiated mice. In contrast, both non-irradiated and irradiated adult melanocytes proliferated and differentiated similarly when they were co-cultured with irradiated adult keratinocytes. These results suggest that the increased proliferative and differentiative activities of mouse epidermal melanocytes from UVB-induced pigmented spots are regulated by keratinocytes, rather than melanocytes.
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Affiliation(s)
- Tomohisa Hirobe
- Radiation Hazards Research Group, National Institute of Radiological Sciences, Anagawa, Inage-ku, Chiba, Japan.
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14
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Furuya R, Akiu S, Ideta R, Naganuma M, Fukuda M, Hirobe T. Changes in the proliferative activity of epidermal melanocytes in serum-free primary culture during the development of ultraviolet radiation B-induced pigmented spots in hairless mice. PIGMENT CELL RESEARCH 2002; 15:348-56. [PMID: 12213091 DOI: 10.1034/j.1600-0749.2002.02035.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Long-term exposure to ultraviolet radiation B (UVB) induced pigmented spots in the dorsal skin of hairless mice of strain (HR-1 X HR/De)F1. To clarify the cellular mechanism for the development of these UVB-induced pigmented spots, we investigated changes in the proliferative activity of epidermal melanoblasts and melanocytes in the dorsal skin at various weeks after UVB irradiation. Epidermal cell suspensions from the dorsal skin of hairless mice were cultured in a serum-free medium supplemented with dibutyryl adenosine 3':5'-cyclic monophosphate (DBcAMP) and basic fibroblast growth factor (bFGF). The suspensions were prepared from dorsal skins of mice exposed to UVB for 4 weeks (the stage of hyperpigmentation). Suspensions were also prepared from mice at 3 (the stage of depigmentation), 8 (the stage of appearance of pigmented spots), 20 (the stage of development of small-sized pigmented spots) and 37 (the stage of development of medium-sized pigmented spots) weeks after the cessation of 8-week UVB exposure. At the stage of hyperpigmentation the proliferative activity of melanoblasts and melanocytes was suppressed. With the development of pigmented spots, the proliferative activity of undifferentiated melanoblasts gradually increased, and then followed the increase in the proliferative activity of differentiated melanocytes. These results suggest that the proliferative activity of epidermal melanoblasts and melanocytes in UVB-irradiated skin increases with the development of pigmented spots.
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Affiliation(s)
- Rikako Furuya
- Shiseido Research Center, Hayabuchi, Kouhoku-ku, Yokohama, Japan
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15
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Melanocyte destruction and repigmentation in vitiligo: A model for nerve cell damage and regrowth. J Biomed Sci 2002. [DOI: 10.1007/bf02254984] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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16
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Lei TC, Virador VM, Vieira WD, Hearing VJ. A melanocyte-keratinocyte coculture model to assess regulators of pigmentation in vitro. Anal Biochem 2002; 305:260-8. [PMID: 12054455 DOI: 10.1006/abio.2002.5665] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Many melanocyte or skin equivalent models have been used to evaluate the potential efficacy of melanogenic compounds to regulate pigmentation, but there has been great variation in results, partially stemming from the use of different cell lines and diverse conditions for the melanogenic assays. In an earlier report, we optimized a microtiter format assay system to screen potential bioactive compounds using immortalized melan-a melanocytes. That assay system, termed the STOPR protocol, allowed effects on melanocyte proliferation and differentiation to be assessed in a highly sensitive, reproducible, and cost-effective manner. However, in the skin and hair, melanocytes interact with keratinocytes, fibroblasts, and other cell types, and testing of putative bioactive compounds on melanocytes alone in culture does not allow one to observe the interactions with those other cell types, such as would occur in vivo. Therefore, we developed a melanocyte-keratinocyte coculture protocol that allows testing of compounds for potential effects on pigmentation in a more physiologically relevant context. It is a sensitive, reproducible, and reliable model for testing melanogenic regulators, and we have standardized it with known melanogenic inhibitors (hydroquinone, arbutin, kojic acid, and niacinamide) and stimulators (alpha-melanocyte-stimulating hormone, 8-methoxypsoralen, and 3,4-dihydroxyphenylalanine). This coculture system allows for large-scale screening of candidate compounds in conjunction with the STOPR protocol and provides a more physiologically relevant system to study melanocyte-keratinocyte interactions and to elucidate the regulatory mechanisms of melanogenic compounds.
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Affiliation(s)
- Tie Chi Lei
- Pigment Cell Biology Section, Laboratory of Cell Biology, Bethesda, Maryland 20892, USA
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17
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Hedley SJ, Layton C, Heaton M, Chakrabarty KH, Dawson RA, Gawkrodger DJ, MacNeil S. Fibroblasts play a regulatory role in the control of pigmentation in reconstructed human skin from skin types I and II. PIGMENT CELL RESEARCH 2002; 15:49-56. [PMID: 11837456 DOI: 10.1034/j.1600-0749.2002.00067.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Human melanocytes in monolayer culture are extremely dependent on a wide range of soluble signals for their proliferation and melanogenesis. The advent of three-dimensional models of reconstructed skin allows one to ask questions of how these cells are regulated within a setting which more closely approximates normal skin. The purpose of this study was to investigate to what extent melanocytes within a reconstructed skin model are sensitive to regulation by dermal fibroblasts, basement membrane (BM) proteins and the addition of alpha-melanocyte-stimulating hormone (alpha-MSH). Sterilized acellular de-epidermized dermis (prepared to retain BM proteins or deliberately denuded of BM by enzymatic treatment) from skin type I or II was reconstituted with fibroblasts, melanocytes and keratinocytes. In all but one case (9/10), cell donors were skin type I or II. The presence of BM antigens was found to be necessary for positional orientation of the melanocytes; in the absence of BM, melanocytes moved into the upper keratinocyte layer pigmenting spontaneously. Addition of fibroblasts suppressed the extent of spontaneous pigmentation of melanocytes within this model. Neither alpha-MSH nor cholera toxin induced pigmentation in this model despite the fact that melanocytes clearly had the ability to synthesize pigment.
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Affiliation(s)
- Susan J Hedley
- University Section of Medicine, Division of Clinical Sciences, Northern General Hospital, Sheffield, UK
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18
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Leszczyniecka M, Roberts T, Dent P, Grant S, Fisher PB. Differentiation therapy of human cancer: basic science and clinical applications. Pharmacol Ther 2001; 90:105-56. [PMID: 11578655 DOI: 10.1016/s0163-7258(01)00132-2] [Citation(s) in RCA: 228] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Current cancer therapies are highly toxic and often nonspecific. A potentially less toxic approach to treating this prevalent disease employs agents that modify cancer cell differentiation, termed 'differentiation therapy.' This approach is based on the tacit assumption that many neoplastic cell types exhibit reversible defects in differentiation, which upon appropriate treatment, results in tumor reprogramming and a concomitant loss in proliferative capacity and induction of terminal differentiation or apoptosis (programmed cell death). Laboratory studies that focus on elucidating mechanisms of action are demonstrating the effectiveness of 'differentiation therapy,' which is now beginning to show translational promise in the clinical setting.
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Affiliation(s)
- M Leszczyniecka
- Department of Urology, Herbert Irving Comprehensive Cancer Center, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA
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19
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Abdel-Naser MB. Differential effects on melanocyte growth and melanization of low vs. high calcium keratinocyte-conditioned medium. Br J Dermatol 1999; 140:50-5. [PMID: 10215767 DOI: 10.1046/j.1365-2133.1999.02606.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Epidermal keratinocytes secrete several growth factors that stimulate melanocyte proliferation and melanin pigment synthesis in vitro. As the epidermis is formed of two distinct layers, i.e. basal cell layer and suprabasal cell layers, and both are functionally and biologically different compartments, it was interesting to investigate which type of epidermal keratinocytes modulate melanocyte proliferation and function most. Normal human epidermal melanocytes (HMel) were incubated with melanocyte-conditioned medium (M-CM) and low Ca2+ and high Ca2+ keratinocyte-conditioned medium (K-CM) obtained from the same skin source of melanocytes. The morphology, proliferation rate and melanin synthesis were evaluated at days 3, 6 and 12 of incubation. The results showed no evidence of major morphological changes in the epidermal melanocytes with any of the conditioned media, although marked dendrite formation was observed in coculture of melanocytes and differentiated keratinocytes. On the other hand, low Ca2+ K-CM induced a mild but statistically significant stimulation of melanocyte growth in a time-dependent manner. The significant percentage increase was evident on day 6 (124.6%, P < 0.05) and on day 12 (138.1%, P < 0.01) of incubation. In contrast, high Ca2+ K-CM showed no significant effect on melanocyte proliferation (P > 0.05). Both low Ca2+ and high Ca2+ K-CM stimulated melanin synthesis, although synthesis induced by low Ca2+ K-CM was higher than that of high Ca2+ K-CM. The significant percentage increase induced by low Ca2+ K-CM was evident on day 6 (117.9%, P < 0.05) and on day 12 (127.8%, P < 0.05) of incubation, whereas it was evident with high Ca2+ K-CM only on day 12 (119.7%, P < 0.05) of incubation. It is concluded from the above data that keratinocytes grown at a low Ca2+ level release factors that stimulate melanocyte proliferation as well as melanin synthesis, whereas keratinocytes grown at a high Ca2+ level release factors that only stimulate melanin synthesis. This may provide an explanation of the anatomical position of melanocytes and may play a part in the pigmentary changes following injury to epidermal cells.
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Affiliation(s)
- M B Abdel-Naser
- Department of Dermatology and Venereology, Ain Shams University, Cairo, Egypt
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20
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Nakazawa K, Kalassy M, Sahuc F, Collombel C, Damour O. Pigmented human skin equivalent--as a model of the mechanisms of control of cell-cell and cell-matrix interactions. Med Biol Eng Comput 1998; 36:813-20. [PMID: 10367475 DOI: 10.1007/bf02518888] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The melanin pigment system in human skin is extraordinarly well developed and assures the photoprotection of the skin against harmful solar radiation. Specific cell-cell interactions between one melanocytes and keratinocytes play a fundamental role in the regulation of melanogenesis and melanin pigementation, the two key elements of this system, giving rise to the concept of a structural, functional collaborative 'epidermal melanin unit,' Early experiments strongly suggested that melanocyte growth and differentiation are regulated by paracrine factors from keratinocytes and other skin cells. In addition, co-culture studies with keratinocytes has shown that the extracellular matrix acts as a local environmental signal for dendrite formation and melanogenesis. Attempts to reconstruct pigmented human skin in vitro have made great progress over the last decade. The behavior of cells in these pigmented human skin equivalents closely resembles that in vivo, and the cells can still respond to appropriate extrinsic regulatory stimuli such as ultraviolet radiation. Keratinocytes and fibroblasts have been shown to be active partners in the regulation of melanocyte distribution, viability and other differentiation functions, presumably by direct contact and the effects of various soluble paracrine factors. By reproducing cell-cell and cell-matrix interactions, these culture systems provide a promising experimental model for investigating regulation of the skin pigmentary system and the role of photoprotection against harmful solar radiation.
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Affiliation(s)
- K Nakazawa
- Laboratory of Skin Substitutes, Edouard Herriot Hospital, Lyon, France
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21
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Furuya R, Akiu S, Naganuma M, Fukuda M, Hirobe T. The proliferation and differentiation of neonatal epidermal melanocytes in F1 hairless mice of HR-1 x HR/De in serum-free culture. J Dermatol 1998; 25:211-21. [PMID: 9609977 DOI: 10.1111/j.1346-8138.1998.tb02384.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To investigate the characteristics of the proliferation and differentiation of epidermal melanocytes in F1 hairless mice of HR-1 x HR/De parents in vitro, cell suspensions of the neonatal epidermis were cultured in a serum-free medium supplemented with dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP) and/or basic fibroblast growth factor (bFGF). The differentiation of melanocytes was induced by treatment with DBcAMP. In contrast, the sustained proliferation of melanoblasts was induced by combined treatment with DBcAMP and bFGF. The melanoblasts could be subcultured in serum-free medium supplemented with the two factors in the presence of keratinocytes, but not in their absence. This is the first report of successful culture of melanoblasts and melanocytes from hairless mice; it is expected to be useful in understanding the mechanism of the development of pigmented spots in the epidermis of (HR-1 x HR/De)F1 mice, which are reported to be induced by repeated exposure to ultraviolet light B.
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Affiliation(s)
- R Furuya
- Shiseido Research Center, Yokohama, Japan
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22
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Hedley SJ, Gawkrodger DJ, Weetman AP, Macneil S. alpha-MSH and melanogenesis in normal human adult melanocytes. PIGMENT CELL RESEARCH 1998; 11:45-56. [PMID: 9523335 DOI: 10.1111/j.1600-0749.1998.tb00710.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Normal human skin melanocytes do not pigment consistently to alpha-melanocyte stimulating hormone (alpha-MSH) in culture. The aim of this study was to establish media conditions in which to obtain a reproducible melanogenic response to alpha-MSH in these cells. Twenty-five media of varying mitogen composition were examined. As previously noted by other workers, melanocyte morphology and proliferation are greatly affected by media composition. However, under the majority of media conditions that supported melanocyte survival and proliferation, cells did not respond to alpha-MSH with any consistent increase in dopa oxidase activity or melanin content. In only one medium condition, where basic fibroblast growth factor (bFGF) was the sole mitogen present, alpha-MSH induced both an increase in dopa oxidase activity (at 48%) and in melanin content (of 283%).
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Affiliation(s)
- S J Hedley
- University Department of Medicine, Northern General Hospital, Sheffield, United Kingdom
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23
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Kippenberger S, Bernd A, Bereiter-Hahn J, Ramirez-Bosca A, Kaufmann R. The mechanism of melanocyte dendrite formation: the impact of differentiating keratinocytes. PIGMENT CELL RESEARCH 1998; 11:34-7. [PMID: 9523333 DOI: 10.1111/j.1600-0749.1998.tb00708.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In human epidermis one dendritic melanocyte interacts with about 36 keratinocytes and supplies them with melanin. In contrast to the vivo situation melanocytes in culture are far less dendritic. In the present study different culture systems were tested in order to observe the mechanism of melanocyte dendrite formation. In particular, we focused on the role of keratinocytes in this process. Time lapse studies revealed that only differentiated keratinocytes enhance melanocyte dendricity. Differentiated keratinocytes form connected cell sheets, which attach to part of the melanocyte plasma membrane. By contraction and retraction of keratinocyte units, new dendrites were drawn out from the melanocytes. Melanocytes remain passive during this process, which is indicated by the observation that sometimes extended dendrites could not withstand the tension and shear.
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Affiliation(s)
- S Kippenberger
- Zentrum der Dermatologie und Venerologie, Klinikum der Johann Wolfgang Goethe Universität, Frankfurt/Main, Germany
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24
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Hedley SJ, Wagner M, Bielby S, Smith-Thomas L, Gawkrodger DJ, MacNeil S. The influence of extracellular matrix proteins on cutaneous and uveal melanocytes. PIGMENT CELL RESEARCH 1997; 10:54-9. [PMID: 9170163 DOI: 10.1111/j.1600-0749.1997.tb00466.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Cutaneous and ocular melanocytes are routinely cultured in complex mitogen-rich media. The physiological regulation of melanocyte proliferation and differentiation is not yet fully defined and this study summarises several separate lines of evidence which suggest that, in vivo, some of the signals required for melanocyte proliferation and differentiation may derive from extracellular matrix (ECM) proteins adjacent to these cells. Culture of cutaneous and uveal melanocytes on cell-derived and individual ECM proteins was found to influence cell morphology with such effects being most noticeable in mitogen-deficient media. Similarly, cell-derived and individual ECM proteins increased tyrosinase activity in normal cutaneous melanocytes and effects of these ECM proteins were seen most consistently in mitogen-deficient media. Uveal melanocytes (as has been reported for cutaneous melanocytes) showed preferential attachment to fibronectin over other ECM substrates. This attachment was particularly sensitive to drugs which affected intracellular calcium or calmodulin activity. Acute addition of fibronectin to coverslips of uveal melanocytes loaded with Fura-2 produced an acute and transient increase in intracellular calcium which was more prevalent in low density than higher density cells. We conclude that ECM proteins in vitro are capable of influencing melanocyte morphology, tyrosinase activity, and proliferation and that an ECM-induced elevation in intracellular calcium may be part of the signalling system that transmits ECM information into the cell.
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Affiliation(s)
- S J Hedley
- University Department of Medicine, Northern General Hospital, Sheffield, United Kingdom
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25
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Hedley S, Gawkrodger DJ, Weetman AP, MacNeil S. Investigation of the influence of extracellular matrix proteins on normal human melanocyte morphology and melanogenic activity. Br J Dermatol 1996; 135:888-97. [PMID: 8977708 DOI: 10.1046/j.1365-2133.1996.d01-1091.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Several studies have indicated that extracellular matrix (ECM) proteins can influence melanocyte behaviour in vitro. However, the choice of medium is known to have a profound effect on melanocyte behaviour and it is currently difficult to ascribe which reported effects are due to ECM proteins and those which are attributable to the medium used in these different studies. The purpose of this study was to learn more about the influence of ECM proteins on melanocyte function by examining a range of cell-derived and individual ECM proteins for their impact on melanocyte tyrosinase activity in cells cultured under conditions of varying mitogenic drive. We found that ECM derived from human dermal fibroblasts, bovine endothelial cells and a human endothelial cell line as well as collagen I, collagen IV, fibronectin, and to a lesser extent laminin, were all capable of increasing tyrosinase activity in cultures of normal melanocytes. Effects of these ECM were seen most consistently in media with relatively few mitogens, for example ECM proteins influenced melanocyte morphology and this was seen most readily in cells cultured in medium without any mitogens (which ordinarily fails to support melanocyte survival). This study illustrates that ECM proteins can influence melanocyte morphology, proliferation, and tyrosinase activity in vitro and supports a possible role of ECM proteins in the regulation of melanocyte function in vivo.
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Affiliation(s)
- S Hedley
- University Department of Medicine, Northern General Hospital, Sheffield, U.K
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26
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Le Poole IC, Van den Wijngaard RM, Verkruisen RP, Lamers WH, Troost D, Westerhof W, Das PK. Foetal human melanocytes: in situ detection, in vitro culture and differentiation characteristics at 6-11 weeks EGA. PIGMENT CELL RESEARCH 1996; 9:126-33. [PMID: 8888311 DOI: 10.1111/j.1600-0749.1996.tb00100.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In vivo, melanocytes were detected in epidermis from human tissue of 6.5 weeks estimated gestinational age (EGA) and older. We have successfully established melanocyte monocultures from tissue of 9 to 10 weeks EGA. To our knowledge, this is the first report on physiology of human foetal melanocytes in monoculture. In culture, such melanocytes retained foetal characteristics. Proliferation rates noted were markedly higher (approximately 2.7-fold) when compared to those in cultures of neonatal melanocytes. Moreover, when analyzing cellular phenotypes by markers for cells of the melanocytic lineage, foetal cells isolated from tissue of 9 weeks EGA reproducibly showed expression of the high molecular weight (HMW) antigen and c-kit to an extent intermediate to that found in neonatal melanocytes and M14 melanoma cells. Such differential expression was not observed if cells were isolated from tissue of 10 weeks EGA, indicating that the foetal environment provides essential differentiation stimuli during the 10th week of gestation. Moreover, these results are supportive of the theory that malignant transformation involves a process of dedifferentiation. In all, human foetal melanocyte culture provides a useful model to investigate pigment cell differentiation.
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Affiliation(s)
- I C Le Poole
- Department of Dermatology, Amsterdam University, The Netherlands
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27
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Nakazawa K, Nakazawa H, Bonnard M, Damour O, Collombel C. Ca2+ and UVB radiation have no effect on E-cadherin-mediated melanocyte-keratinocyte adhesion. PIGMENT CELL RESEARCH 1995; 8:255-62. [PMID: 8789200 DOI: 10.1111/j.1600-0749.1995.tb00672.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Direct cell-cell contact between melanocytes and keratinocytes has been shown to play an important role in the regulation of human melanocyte function and skin pigmentation. An important role for the calcium-dependent epithelium-specific cell adhesion molecule, E-cadherin, in melanocyte-keratinocyte adhesion was suggested previously. To further clarify regulation of E-cadherin-mediated melanocyte-keratinocyte interactions, we investigated the effects of physiological (Ca2+) and environmental (ultraviolet B [UVB] radiation) stimuli on the expression and functional activity of E-cadherin in melanocyte-keratinocyte adhesion. Expression of E-cadherin mRNA was detected by Northern blot analysis in cultured normal human melanocytes at levels similar to those in keratinocytes. Flow cytometry analysis with anti-human and anti-mouse-E-cadherin antibodies (anti-uvomorulin and ECCD-2) showed that cultured normal human keratinocytes, melanocytes, and two metastatic melanoma cell lines express E-cadherin strongly on the cell surfaces. Melanocyte adhesion, particularly to differentiating keratinocytes (cultured in 1.2 mM calcium) but not to proliferating keratinocytes or to fibroblasts, was decreased by 41.7 +/- 4.5% in the absence of 1 mM Ca2+ during the binding assay. Addition of anti-mouse-E-cadherin antibody (ECCD-1) to the binding assay inhibited the adhesion of melanocytes to differentiating keratinocytes by 88.2 +/- 1.1%, while addition of anti-P-cadherin antibody (PCD-1) had no effect. The levels of E-cadherin expression in melanocytes were not changed by the presence of calcium (1 mM) in the medium or by UVB irradiation (20 mJ/cm2) for one day before flow cytometry analysis. Moreover, these treatments had no effect on melanocyte-keratinocyte adhesion. These results demonstrate that E-cadherin is strongly involved in melanocyte adhesion to keratinocytes and suggest the implication of E-cadherin in the overall regulation of the skin pigmentary system.
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Affiliation(s)
- K Nakazawa
- Skin Substitute Laboratory, CNRS-URA 1341, Lyon, France
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