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Wang YG, Yuan VL, Liao XH. Genetic lineage tracing in skin reveals predominant expression of HEY2 in dermal papilla during telogen and that HEY2 + cells contribute to the regeneration of dermal cells during wound healing. Exp Dermatol 2023; 32:2176-2179. [PMID: 37649203 DOI: 10.1111/exd.14917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/20/2023] [Accepted: 08/16/2023] [Indexed: 09/01/2023]
Abstract
Dermal papilla (DP) cells are specialized mesenchymal cells that play a crucial role in regulating hair morphology, colour and growth through the secretion of specific factors. It is still unclear what the source of progenitor cells is for dermal cell regeneration during wound healing, and whether DP cells are involved in this process. We analyzed the gene expression profile of various skin cell populations using existing datasets and found that the Hey2 gene was predominantly expressed in DP cells. We introduced Hey2-CreERT2 knockin mice and crossed them with Rosa26-ZsGreen reporter mice. After induction in the double transgenic mice by administration of tamoxifen, the reporter ZsGreen was found to be predominantly expressed in DP cells both at anagen and telogen phases, and broadly expressed in some other dermal cells at anagen. We also created a wound after tamoxifen induction, and found there were abundant ZsGreen+ cells in the regenerated dermis. We conclude that the HEY2+ DP cells and dermal cells exhibit some stemness properties and can contribute to the dermal cell regeneration during wound healing.
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Affiliation(s)
- Yan-Ge Wang
- School of Medicine, Shanghai University, Shanghai, China
| | - Vicky Lan Yuan
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Xin-Hua Liao
- School of Life Sciences, Shanghai University, Shanghai, China
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2
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Sibony-Benyamini H, Aamar E, Enshell-Seijffers D. Hdac1 and Hdac2 regulate the quiescent state and survival of hair-follicle mesenchymal niche. Nat Commun 2023; 14:4820. [PMID: 37563109 PMCID: PMC10415406 DOI: 10.1038/s41467-023-40573-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 08/02/2023] [Indexed: 08/12/2023] Open
Abstract
While cell division is essential for self-renewal and differentiation of stem cells and progenitors, dormancy is required to maintain the structure and function of the stem-cell niche. Here we use the hair follicle to show that during growth, the mesenchymal niche of the hair follicle, the dermal papilla (DP), is maintained quiescent by the activity of Hdac1 and Hdac2 in the DP that suppresses the expression of cell-cycle genes. Furthermore, Hdac1 and Hdac2 in the DP promote the survival of DP cells throughout the hair cycle. While during growth and regression this includes downregulation of p53 activity and the control of p53-independent programs, during quiescence, this predominantly involves p53-independent mechanisms. Remarkably, Hdac1 and Hdac2 in the DP during the growth phase also participate in orchestrating the hair cycle clock by maintaining physiological levels of Wnt signaling in the vicinity of the DP. Our findings not only provide insight into the molecular mechanism that sustains the function of the stem-cell niche in a persistently changing microenvironment, but also unveil that the same mechanism provides a molecular toolbox allowing the DP to affect and fine tune the microenvironment.
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Affiliation(s)
- Hadas Sibony-Benyamini
- The Laboratory of Developmental Biology, The Azrieli Faculty of Medicine, Bar Ilan University, 8 Henrietta Szold, Safed, Israel
| | - Emil Aamar
- The Laboratory of Developmental Biology, The Azrieli Faculty of Medicine, Bar Ilan University, 8 Henrietta Szold, Safed, Israel
| | - David Enshell-Seijffers
- The Laboratory of Developmental Biology, The Azrieli Faculty of Medicine, Bar Ilan University, 8 Henrietta Szold, Safed, Israel.
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3
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Wei H, Du S, Parksong J, Pasolli HA, Matte-Martone C, Regot S, Gonzalez LE, Xin T, Greco V. Organ function is preserved despite reorganization of niche architecture in the hair follicle. Cell Stem Cell 2023; 30:962-972.e6. [PMID: 37419106 PMCID: PMC10362479 DOI: 10.1016/j.stem.2023.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 05/01/2023] [Accepted: 06/07/2023] [Indexed: 07/09/2023]
Abstract
The ability of stem cells to build and replenish tissues depends on support from their niche. Although niche architecture varies across organs, its functional importance is unclear. During hair follicle growth, multipotent epithelial progenitors build hair via crosstalk with their remodeling fibroblast niche, the dermal papilla, providing a powerful model to functionally interrogate niche architecture. Through mouse intravital imaging, we show that dermal papilla fibroblasts remodel individually and collectively to form a morphologically polarized, structurally robust niche. Asymmetric TGF-β signaling precedes morphological niche polarity, and loss of TGF-β signaling in dermal papilla fibroblasts leads them to progressively lose their stereotypic architecture, instead surrounding the epithelium. The reorganized niche induces the redistribution of multipotent progenitors but nevertheless supports their proliferation and differentiation. However, the differentiated lineages and hairs produced by progenitors are shorter. Overall, our results reveal that niche architecture optimizes organ efficiency but is not absolutely essential for organ function.
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Affiliation(s)
- Haoyang Wei
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Shuangshuang Du
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Jeeun Parksong
- Departments of Cell Biology and Pathology, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - H Amalia Pasolli
- Electron Microscopy Resource Center, The Rockefeller University, New York, NY 10065, USA
| | | | - Sergi Regot
- Department of Molecular Biology and Genetics, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA
| | - Lauren E Gonzalez
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Tianchi Xin
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA.
| | - Valentina Greco
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Departments of Cell Biology and Dermatology, Yale Stem Cell Center, Yale Cancer Center, Yale School of Medicine, New Haven, CT 06510, USA.
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4
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Zheng Q, Ye N, Bao P, Zhang X, Wang F, Ma L, Chu M, Guo X, Liang C, Pan H, Yan P. Construction of transcriptome atlas of white yak hair follicle during anagen and catagen using single-cell RNA sequencing. BMC Genomics 2022; 23:813. [PMID: 36482306 PMCID: PMC9730603 DOI: 10.1186/s12864-022-09003-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 11/10/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND As the direct organ of villus, hair follicles have obvious seasonal cycles. The hair follicle cycle is orchestrated by multiple cell types that together direct cell renewal and differentiation. But the regulation property of hair follicle cells from anagen to catagen in yak is still unknown. RESULTS In this study, single-cell RNA sequencing was performed on 24,124 single cells of the scapular skin from white yak. Based on tSNE cluster analysis, the cell types of IFE-DC, epidermal cell lines, fibroblasts, keratinocytes, IRS, DS, INFU, and other cells in yak hair follicles during anagen and catagen were successfully identified, and the gene expression profiles were described. The GO enrichment analysis indicated the different cells characteristic genes to be mainly enriched in the epidermal development, epithelial cell differentiation and wound healing pathways. The pseudotime trajectory analysis described the differentiation trajectory of the epidermal lineage and dermal lineage of the hair follicle during anagen and catagen. Moreover, the dynamic changes of the genes like LHX2, KRT25, and KRT71 were found to be highly expressed in HS and IRS, but not in the IFE-DC, INFU, and keratinocyte during differentiation. CONCLUSIONS Our results analyzed the time-varying process of gene expression in the dermal cell lineage and epidermal cell lineage of hair follicles during anagen and catagen during fate differentiation was expounded at the single cell level, revealing the law of fate specialization of different types of cells. In addition, based on the enrichment analysis, the transcriptional regulatory factors involved in the different cell fates were also revealed. These results will help to enhance our understanding of yak hair follicle cycle and promote the development and utilization of yak villus.
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Affiliation(s)
- Qingbo Zheng
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Life Science and Engineering College, Northwest Minzu University, Lanzhou, 730030, China
| | - Na Ye
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Life Science and Engineering College, Northwest Minzu University, Lanzhou, 730030, China
| | - Pengjia Bao
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
| | - Xiaolan Zhang
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
| | - Fubin Wang
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Life Science and Engineering College, Northwest Minzu University, Lanzhou, 730030, China
| | - Lanhua Ma
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Life Science and Engineering College, Northwest Minzu University, Lanzhou, 730030, China
| | - Min Chu
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
| | - Xian Guo
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
| | - Chunnian Liang
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China
| | - Heping Pan
- Life Science and Engineering College, Northwest Minzu University, Lanzhou, 730030, China.
| | - Ping Yan
- Key Laboratory of Yak Breeding Engineering of Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China.
- Key Laboratory of Animal Genetics and Breeding On Tibetan Plateau, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, 730050, China.
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5
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Sox2 in the dermal papilla regulates hair follicle pigmentation. Cell Rep 2022; 40:111100. [PMID: 35858560 DOI: 10.1016/j.celrep.2022.111100] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 04/15/2022] [Accepted: 06/23/2022] [Indexed: 12/18/2022] Open
Abstract
Within the hair follicle (HF) niche, dermal papilla (DP) cells are well known for the hair induction capacity; however, DP cell signaling also regulates HF pigmentation. Here we describe how Sox2 in the DP is a key regulator of melanocyte signaling. To study the largely unknown regulatory role the DP has on hair pigmentation, we characterize leptin receptor (Lepr) expression in the skin and as a genetic tool to target the DP. Sox2 ablation in the DP results in a phenotypic switch from eumelanin to pheomelanin. Mechanistically, we describe a temporal upregulation of Agouti and downregulation of Corin, directly by Sox2 in the DP. We also show that bone morphogenic protein (BMP) signaling regulation by Sox2 is responsible for downregulating MC1R, Dct, and Tyr in melanocytes of Sox2 cKO mice. Thus, we demonstrate that Sox2 in the DP regulates not only the choice of hair pigment but also the overall HF pigment production.
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6
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Abreu CM, Marques AP. Recreation of a hair follicle regenerative microenvironment: Successes and pitfalls. Bioeng Transl Med 2022; 7:e10235. [PMID: 35079623 PMCID: PMC8780054 DOI: 10.1002/btm2.10235] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 05/15/2021] [Accepted: 05/18/2021] [Indexed: 12/19/2022] Open
Abstract
The hair follicle (HF) is an exquisite skin appendage endowed with cyclical regenerative capacity; however, de novo follicle formation does not naturally occur. Consequently, patients suffering from extensive skin damage or hair loss are deprived of the HF critical physiological and/or aesthetic functions, severally compromising skin function and the individual's psychosocial well-being. Translation of regenerative strategies has been prevented by the loss of trichogenic capacity that relevant cell populations undergo in culture and by the lack of suitable human-based in vitro testing platforms. Here, we provide a comprehensive overview of the major difficulties associated with HF regeneration and the approaches used to overcome these drawbacks. We describe key cellular requirements and discuss the importance of the HF extracellular matrix and associated signaling for HF regeneration. Finally, we summarize the strategies proposed so far to bioengineer human HF or hair-bearing skin models and disclose future trends for the field.
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Affiliation(s)
- Carla M. Abreu
- 3B's Research Group, I3Bs ‐ Research Institute on Biomaterials, Biodegradables and Biomimetics, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAvePark–Parque de Ciência e Tecnologia, University of MinhoGuimarãesPortugal
- ICVS/3B's–PT Government Associate LaboratoryGuimarãesPortugal
| | - Alexandra P. Marques
- 3B's Research Group, I3Bs ‐ Research Institute on Biomaterials, Biodegradables and Biomimetics, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAvePark–Parque de Ciência e Tecnologia, University of MinhoGuimarãesPortugal
- ICVS/3B's–PT Government Associate LaboratoryGuimarãesPortugal
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7
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Aamar E, Laron EA, Asaad W, Harshuk-Shabso S, Enshell-Seijffers D. Hair-follicle mesenchymal stem-cell activity during homeostasis and wound healing. J Invest Dermatol 2021; 141:2797-2807.e6. [PMID: 34166673 DOI: 10.1016/j.jid.2021.05.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 10/21/2022]
Abstract
The mesenchymal components of the hair follicle, the dermal papilla (DP) and dermal sheath (DS), are maintained by hair-follicle dermal stem cells (hfDSCs), but the position of this stem cell population throughout the hair cycle, its contribution to the maintenance of the dermis and the existence of a migratory axis from the DP to the dermis remain unclear. Here we show that during homeostasis DP and DS cells are confined to their compartments, and during the regression phase of the hair cycle, some undergo apoptosis and subsequently are internalized by nearby adipocytes. In contrast, during wound healing, DP/DS cells move towards the wound, but do not directly participate in follicle neogenesis. Furthermore, hfDSCs, driving the cyclic renewal of the DS during the hair cycle, are heterogeneous and housed during the growth phase within the most proximal part of the DS. Our analysis provides insight into the mechanisms of tissue maintenance and unravels a previously-unknown potential function of adipocytes in phagocytosis.
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Affiliation(s)
- Emil Aamar
- The Laboratory of Developmental Biology, The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Efrat Avigad Laron
- The Laboratory of Developmental Biology, The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Wisal Asaad
- The Laboratory of Developmental Biology, The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Sarina Harshuk-Shabso
- The Laboratory of Developmental Biology, The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - David Enshell-Seijffers
- The Laboratory of Developmental Biology, The Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel.
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8
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Hawkshaw NJ, Hardman JA, Haslam IS, Shahmalak A, Gilhar A, Lim X, Paus R. Identifying novel strategies for treating human hair loss disorders: Cyclosporine A suppresses the Wnt inhibitor, SFRP1, in the dermal papilla of human scalp hair follicles. PLoS Biol 2018; 16:e2003705. [PMID: 29738529 PMCID: PMC5940179 DOI: 10.1371/journal.pbio.2003705] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 04/04/2018] [Indexed: 12/20/2022] Open
Abstract
Hair growth disorders often carry a major psychological burden. Therefore, more effective human hair growth–modulatory agents urgently need to be developed. Here, we used the hypertrichosis-inducing immunosuppressant, Cyclosporine A (CsA), as a lead compound to identify new hair growth–promoting molecular targets. Through microarray analysis we identified the Wnt inhibitor, secreted frizzled related protein 1 (SFRP1), as being down-regulated in the dermal papilla (DP) of CsA-treated human scalp hair follicles (HFs) ex vivo. Therefore, we further investigated the function of SFRP1 using a pharmacological approach and found that SFRP1 regulates intrafollicular canonical Wnt/β-catenin activity through inhibition of Wnt ligands in the human hair bulb. Conversely, inhibiting SFRP1 activity through the SFRP1 antagonist, WAY-316606, enhanced hair shaft production, hair shaft keratin expression, and inhibited spontaneous HF regression (catagen) ex vivo. Collectively, these data (a) identify Wnt signalling as a novel, non–immune-inhibitory CsA target; (b) introduce SFRP1 as a physiologically important regulator of canonical β-catenin activity in a human (mini-)organ; and (c) demonstrate WAY-316606 to be a promising new promoter of human hair growth. Since inhibiting SFRP1 only facilitates Wnt signalling through ligands that are already present, this ‘ligand-limited’ therapeutic strategy for promoting human hair growth may circumvent potential oncological risks associated with chronic Wnt over-activation. Hair loss is a common disorder and can lead to psychological distress. Cyclosporine A, a fungal metabolite commonly used as an immunosuppressant, can potently induce hair growth in humans. However, it cannot be effectively used to restore hair growth because of its toxic profile. In this study, we used Cyclosporine A as a lead compound to identify novel therapeutic targets that can aid the development of new hair growth–promoting agents. Through microarray analysis, we found that the level of the secreted Wnt inhibitor, SFRP1, was significantly reduced by Cyclosporine A. This inspired us to design a new pharmacological approach that uses WAY-316606, a reportedly well-tolerated and specific antagonist of SFRP1, to prolong the growth phase of the hair cycle. We show that WAY-316606 enhances human hair growth ex vivo, suggesting that it is a more targeted hair growth promoter with the potential to treat human hair loss disorders.
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Affiliation(s)
- Nathan J. Hawkshaw
- Centre for Dermatology Research, University of Manchester, Manchester Academic Health Science Centre and NIHR Manchester Biomedical Research Centre, Manchester, United Kingdom
| | - Jonathan A. Hardman
- Centre for Dermatology Research, University of Manchester, Manchester Academic Health Science Centre and NIHR Manchester Biomedical Research Centre, Manchester, United Kingdom
| | - Iain S. Haslam
- Department of Biological Sciences, School of Applied Sciences, University of Huddersfield, Huddersfield, United Kingdom
| | | | - Amos Gilhar
- Skin Research Laboratory, Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Xinhong Lim
- Institute of Medical Biology, Agency for Science, Technology, and Research, Singapore
- Skin Research Institute of Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
- Duke-NUS Medical School, Singapore
| | - Ralf Paus
- Centre for Dermatology Research, University of Manchester, Manchester Academic Health Science Centre and NIHR Manchester Biomedical Research Centre, Manchester, United Kingdom
- Department of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, United States of America
- * E-mail:
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9
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Abstract
The growth of hairs occurs during the anagen phase of the follicle cycle. Hair growth begins with basement membrane-bound stem cells (mother cells) around the dermal papilla neck which continuously bud off daughter cells which further divide as a transient amplifying population. Division ceases as cell line differentiation begins, which entails changes in cell junctions, cell shape and position, and cell-line specific cytoplasmic expression of keratin and trichohyalin. As the differentiating cells migrate up the bulb, nuclear function ceases in cortex, cuticle and inner root sheath (IRS) layers. Past the top of the bulb, cell shape/position changes cease, and there is a period of keratin and keratin-associated protein (KAP) synthesis in fibre cell lines, with increases, in particular of KAP species. A gradual keratinization process begins in the cortex at this point and then non-keratin cell components are increasingly broken down. Terminal cornification, or hardening, is associated with water loss and precipitation of keratin. In the upper follicle, the hair, now in its mature form, detaches from the IRS, which is then extracted of material and becomes fragmented to release the fibre. Finally, the sebaceous and sudoriferous (if present) glands coat the fibre in lipid-rich material and the fibre emerges from the skin. This chapter follows the origin of the hair growth in the lower bulb and traces the development of the various cell lines.
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10
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Wang X, Chen H, Tian R, Zhang Y, Drutskaya MS, Wang C, Ge J, Fan Z, Kong D, Wang X, Cai T, Zhou Y, Wang J, Wang J, Wang S, Qin Z, Jia H, Wu Y, Liu J, Nedospasov SA, Tredget EE, Lin M, Liu J, Jiang Y, Wu Y. Macrophages induce AKT/β-catenin-dependent Lgr5 + stem cell activation and hair follicle regeneration through TNF. Nat Commun 2017; 8:14091. [PMID: 28345588 PMCID: PMC5378973 DOI: 10.1038/ncomms14091] [Citation(s) in RCA: 141] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 11/29/2016] [Indexed: 12/11/2022] Open
Abstract
Skin stem cells can regenerate epidermal appendages; however, hair follicles (HF) lost as a result of injury are barely regenerated. Here we show that macrophages in wounds activate HF stem cells, leading to telogen-anagen transition (TAT) around the wound and de novo HF regeneration, mostly through TNF signalling. Both TNF knockout and overexpression attenuate HF neogenesis in wounds, suggesting dose-dependent induction of HF neogenesis by TNF, which is consistent with TNF-induced AKT signalling in epidermal stem cells in vitro. TNF-induced β-catenin accumulation is dependent on AKT but not Wnt signalling. Inhibition of PI3K/AKT blocks depilation-induced HF TAT. Notably, Pten loss in Lgr5+ HF stem cells results in HF TAT independent of injury and promotes HF neogenesis after wounding. Thus, our results suggest that macrophage-TNF-induced AKT/β-catenin signalling in Lgr5+ HF stem cells has a crucial role in promoting HF cycling and neogenesis after wounding.
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Affiliation(s)
- Xusheng Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Haiyan Chen
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
- Tsinghua-Berkeley Shenzhen Institute (TBSI), Tsinghua University, Shenzhen 518055, China
- State Key Laboratory Breeding Base-Shenzhen Key Laboratory of Chemical Biology, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen, China
| | - Ruiyun Tian
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
- Shenzhen Peiyuan Biotechnology Company, Shenzhen 518055, China
| | - Yiling Zhang
- Department of Orthopedics, The General Hospital of Chinese People's Liberation Army, Beijing 100039, China
| | - Marina S. Drutskaya
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Chengmei Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Jianfeng Ge
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Zhimeng Fan
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Deqiang Kong
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Xiaoxiao Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Ting Cai
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Ying Zhou
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Jingwen Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Jinmei Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Shan Wang
- School of Life Sciences, Tsinghua University, Beijing 100084, China
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Zhihai Qin
- Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Huanhuan Jia
- Guangdong Laboratory Animals Monitoring Institute, Guangdong Provincial Key Laboratory of Laboratory Animals, Guangzhou 510260, China
| | - Yue Wu
- Guangdong Laboratory Animals Monitoring Institute, Guangdong Provincial Key Laboratory of Laboratory Animals, Guangzhou 510260, China
| | - Jia Liu
- College of Life Sciences, Northeast Forestry University, Harbin 100040, China
| | - Sergei A. Nedospasov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Edward E. Tredget
- Wound Healing Research Group, Department of Surgery, University of Alberta, Edmonton, Alberta, Canada ABT6G2E1
| | - Mei Lin
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Jianjun Liu
- Medical Key Laboratory of Health Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen 518054, China
| | - Yuyang Jiang
- State Key Laboratory Breeding Base-Shenzhen Key Laboratory of Chemical Biology, Graduate School at Shenzhen, Tsinghua University, 518055 Shenzhen, China
| | - Yaojiong Wu
- The Shenzhen Key Laboratory of Health Sciences and Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
- Tsinghua-Berkeley Shenzhen Institute (TBSI), Tsinghua University, Shenzhen 518055, China
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11
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陈 若, 苗 勇, 胡 志. [Research progress of skin-derived precursor cells]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2017; 37:420-422. [PMID: 28377365 PMCID: PMC6780441 DOI: 10.3969/j.issn.1673-4254.2017.03.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Indexed: 06/07/2023]
Abstract
As a novel population of neural crest-origin precursor cells, skin-derived precursor cells (SKPs) can be isolated from both embryonic and adult dermis. These cells have important values for research and potential clinical application in wound healing, organ regeneration and disease treatment for advantages in the abundance of cell sources, accessibility, potential of multipotent differentiation, and absence of ethical concerns. Here we review the developmental and anatomical origins of SKPs and their potential application in regenerative medicine. SKPs originate from the embryonic neural crest, and their sources may vary in different areas of the body. SKPs are widely found in the dermis, especially in the dermal papilla (DP), which was known as a niche of SKPs. The multipotent SKPs can used for autologous transplantation and are of vital importance in tissue repair.
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Affiliation(s)
- 若思 陈
- 南方医科大学南方医院,广东 广州 510515Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
- 约翰·霍普金斯大学医学院,马里兰州 巴尔的摩市Medical College,The Johns Hopkins University, Baltimore, United States of America
| | - 勇 苗
- 南方医科大学南方医院,广东 广州 510515Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - 志奇 胡
- 南方医科大学南方医院,广东 广州 510515Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
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12
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Zhang H, Nan W, Wang S, Zhang T, Si H, Wang D, Yang F, Li G. Epidermal growth factor promotes proliferation of dermal papilla cells via Notch signaling pathway. Biochimie 2016; 127:10-8. [DOI: 10.1016/j.biochi.2016.04.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 04/18/2016] [Indexed: 01/06/2023]
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13
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Kaushal GS, Rognoni E, Lichtenberger BM, Driskell RR, Kretzschmar K, Hoste E, Watt FM. Fate of Prominin-1 Expressing Dermal Papilla Cells during Homeostasis, Wound Healing and Wnt Activation. J Invest Dermatol 2015; 135:2926-2934. [PMID: 26288357 PMCID: PMC4650270 DOI: 10.1038/jid.2015.319] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 07/05/2015] [Accepted: 07/22/2015] [Indexed: 12/23/2022]
Abstract
Prominin-1/CD133 (Prom1) is expressed by fibroblasts in the dermal papilla (DP) of the hair follicle (HF). By examining endogenous Prom1 expression and expression of LacZ in the skin of Prom1CreERLacZ (Prom1C-L) mice, in which a CreERT2-IRES-nuclear LacZ cassette is knocked into the first ATG codon of Prom1, we confirmed that Prom1 is expressed in the DP of all developing HFs and also by postnatal anagen follicles. To analyze the fate of Prom1+ DP cells, we crossed Prom1C-L mice with Rosa26-CAG flox/stop/flox tdTomato reporter mice and applied 4-hydroxytamoxifen (4OHT) to back skin at postnatal day (P) 1 and P2. We detected tdTomato+ cells in ~50% of DPs. The proportion of labeled cells per DP increased between P5 and P63, while the total number of cells per DP declined. Following full thickness wounding, there was no migration of tdTomato-labeled cells out of the DP. When β-catenin was activated in Prom1+ DP cells there was an increase in the size of anagen and telogen DP, but the proportion of tdTomato-labeled cells did not increase. We conclude that Prom1+ DP cells do not contribute to dermal repair but are nevertheless capable of regulating DP size via β-catenin-mediated intercellular communication.
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Affiliation(s)
- Grace S Kaushal
- King's College London, Centre for Stem Cells and Regenerative Medicine, Guy's Hospital Campus, London, UK
| | - Emanuel Rognoni
- King's College London, Centre for Stem Cells and Regenerative Medicine, Guy's Hospital Campus, London, UK
| | - Beate M Lichtenberger
- King's College London, Centre for Stem Cells and Regenerative Medicine, Guy's Hospital Campus, London, UK
| | - Ryan R Driskell
- King's College London, Centre for Stem Cells and Regenerative Medicine, Guy's Hospital Campus, London, UK
| | - Kai Kretzschmar
- King's College London, Centre for Stem Cells and Regenerative Medicine, Guy's Hospital Campus, London, UK
| | - Esther Hoste
- King's College London, Centre for Stem Cells and Regenerative Medicine, Guy's Hospital Campus, London, UK
| | - Fiona M Watt
- King's College London, Centre for Stem Cells and Regenerative Medicine, Guy's Hospital Campus, London, UK.
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14
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Sheen YS, Fan SMY, Chan CC, Wu YF, Jee SH, Lin SJ. Visible red light enhances physiological anagen entry in vivo and has direct and indirect stimulative effects in vitro. Lasers Surg Med 2014; 47:50-9. [DOI: 10.1002/lsm.22316] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2014] [Indexed: 01/08/2023]
Affiliation(s)
- Yi-Shuan Sheen
- Department of Dermatology; National Taiwan University Hospital and National Taiwan University College of Medicine; 7 Chung-Shan South Road Taipei 100 Taiwan
| | - Sabrina Mai-Yi Fan
- Institute of Biomedical Engineering; College of Medicine and College of Engineering; National Taiwan University; No. 1, Sec. 1, Jen-Ai Road Taipei 100 Taiwan
| | - Chih-Chieh Chan
- Department of Dermatology; National Taiwan University Hospital and National Taiwan University College of Medicine; 7 Chung-Shan South Road Taipei 100 Taiwan
- Institute of Biomedical Engineering; College of Medicine and College of Engineering; National Taiwan University; No. 1, Sec. 1, Jen-Ai Road Taipei 100 Taiwan
| | - Yueh-Feng Wu
- Institute of Biomedical Engineering; College of Medicine and College of Engineering; National Taiwan University; No. 1, Sec. 1, Jen-Ai Road Taipei 100 Taiwan
| | - Shiou-Hwa Jee
- Department of Dermatology; National Taiwan University Hospital and National Taiwan University College of Medicine; 7 Chung-Shan South Road Taipei 100 Taiwan
| | - Sung-Jan Lin
- Department of Dermatology; National Taiwan University Hospital and National Taiwan University College of Medicine; 7 Chung-Shan South Road Taipei 100 Taiwan
- Institute of Biomedical Engineering; College of Medicine and College of Engineering; National Taiwan University; No. 1, Sec. 1, Jen-Ai Road Taipei 100 Taiwan
- Research Center for Developmental Biology and Regenerative Medicine; National Taiwan University; No. 1, Sec. 4, Roosevelt Road Taipei 106 Taiwan
- Center for Molecular Imaging; National Taiwan University; No. 1, Sec. 4, Roosevelt Road Taipei 106 Taiwan
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15
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Mouse hair cycle expression dynamics modeled as coupled mesenchymal and epithelial oscillators. PLoS Comput Biol 2014; 10:e1003914. [PMID: 25375120 PMCID: PMC4222602 DOI: 10.1371/journal.pcbi.1003914] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 09/08/2014] [Indexed: 02/07/2023] Open
Abstract
The hair cycle is a dynamic process where follicles repeatedly move through phases of growth, retraction, and relative quiescence. This process is an example of temporal and spatial biological complexity. Understanding of the hair cycle and its regulation would shed light on many other complex systems relevant to biological and medical research. Currently, a systematic characterization of gene expression and summarization within the context of a mathematical model is not yet available. Given the cyclic nature of the hair cycle, we felt it was important to consider a subset of genes with periodic expression. To this end, we combined several mathematical approaches with high-throughput, whole mouse skin, mRNA expression data to characterize aspects of the dynamics and the possible cell populations corresponding to potentially periodic patterns. In particular two gene clusters, demonstrating properties of out-of-phase synchronized expression, were identified. A mean field, phase coupled oscillator model was shown to quantitatively recapitulate the synchronization observed in the data. Furthermore, we found only one configuration of positive-negative coupling to be dynamically stable, which provided insight on general features of the regulation. Subsequent bifurcation analysis was able to identify and describe alternate states based on perturbation of system parameters. A 2-population mixture model and cell type enrichment was used to associate the two gene clusters to features of background mesenchymal populations and rapidly expanding follicular epithelial cells. Distinct timing and localization of expression was also shown by RNA and protein imaging for representative genes. Taken together, the evidence suggests that synchronization between expanding epithelial and background mesenchymal cells may be maintained, in part, by inhibitory regulation, and potential mediators of this regulation were identified. Furthermore, the model suggests that impairing this negative regulation will drive a bifurcation which may represent transition into a pathological state such as hair miniaturization. The hair cycle represents a complex process of particular interest in the study of regulated proliferation, apoptosis and differentiation. While various modeling strategies are presented in the literature, none attempt to link extensive molecular details, provided by high-throughput experiments, with high-level, system properties. Thus, we re-analyzed a previously published mRNA expression time course study and found that we could readily identify a sizeable subset of genes that was expressed in synchrony with the hair cycle itself. The data is summarized in a dynamic, mathematical model of coupled oscillators. We demonstrate that a particular coupling scheme is sufficient to explain the observed synchronization. Further analysis associated specific expression patterns to general yet distinct cell populations, background mesenchymal and rapidly expanding follicular epithelial cells. Experimental imaging results are presented to show the localization of candidate genes from each population. Taken together, the results describe a possible mechanism for regulation between epithelial and mesenchymal populations. We also described an alternate state similar to hair miniaturization, which is predicted by the oscillator model. This study exemplifies the strengths of combining systems-level analysis with high-throughput experimental data to obtain a novel view of a complex system such as the hair cycle.
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16
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Nissimov JN, Das Chaudhuri AB. Hair curvature: a natural dialectic and review. Biol Rev Camb Philos Soc 2014; 89:723-66. [PMID: 24617997 DOI: 10.1111/brv.12081] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 12/18/2013] [Accepted: 01/01/2014] [Indexed: 12/19/2022]
Abstract
Although hair forms (straight, curly, wavy, etc.) are present in apparently infinite variations, each fibre can be reduced to a finite sequence of tandem segments of just three types: straight, bent/curly, or twisted. Hair forms can thus be regarded as resulting from genetic pathways that induce, reverse or modulate these basic curvature modes. However, physical interconversions between twists and curls demonstrate that strict one-to-one correspondences between them and their genetic causes do not exist. Current hair-curvature theories do not distinguish between bending and twisting mechanisms. We here introduce a multiple papillary centres (MPC) model which is particularly suitable to explain twisting. The model combines previously known features of hair cross-sectional morphology with partially/completely separated dermal papillae within single follicles, and requires such papillae to induce differential growth rates of hair cortical material in their immediate neighbourhoods. The MPC model can further help to explain other, poorly understood, aspects of hair growth and morphology. Separate bending and twisting mechanisms would be preferentially affected at the major or minor ellipsoidal sides of fibres, respectively, and together they exhaust the possibilities for influencing hair-form phenotypes. As such they suggest dialectic for hair-curvature development. We define a natural-dialectic (ND) which could take advantage of speculative aspects of dialectic, but would verify its input data and results by experimental methods. We use this as a top-down approach to first define routes by which hair bending or twisting may be brought about and then review evidence in support of such routes. In particular we consider the wingless (Wnt) and mammalian target of rapamycin (mTOR) pathways as paradigm pathways for molecular hair bending and twisting mechanisms, respectively. In addition to the Wnt canonical pathway, the Wnt/Ca(2+) and planar cell polarity (PCP) pathways, and others, can explain many alternatives and specific variations of hair bending phenotypes. Mechanisms for hair papilla budding or its division by bisection or fission can explain MPC formation. Epithelial-to-mesenchymal (EMT) and mesenchymal-to-epithelial (MET) transitions, acting in collaboration with epithelial-mesenchymal communications are also considered as mechanisms affecting hair growth and its bending and twisting. These may be treated as sub-mechanisms of an overall development from neural-crest stem cell (NCSC) lineages to differentiated hair follicle (HF) cell types, thus providing a unified framework for hair growth and development.
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17
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Ohyama M, Veraitch O. Strategies to enhance epithelial-mesenchymal interactions for human hair follicle bioengineering. J Dermatol Sci 2013; 70:78-87. [PMID: 23557720 DOI: 10.1016/j.jdermsci.2013.02.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Revised: 02/11/2013] [Accepted: 02/13/2013] [Indexed: 12/17/2022]
Abstract
Hair follicle morphogenesis and regeneration depend on intensive but well-orchestrated interactions between epithelial and mesenchymal components. Accordingly, the enhancement of this crosstalk represents a promising approach to achieve successful bioengineering of human hair follicles. The present article summarizes the techniques, both currently available and potentially feasible, to promote epithelial-mesenchymal interactions (EMIs) necessary for human hair follicle regeneration. The strategies include the preparation of epithelial components with high receptivity to trichogenic dermal signals and/or mesenchymal cell populations with potent hair inductive capacity. In this regard, bulge epithelial stem cells, keratinocytes predisposed to hair follicle fate or keratinocyte precursor cells with plasticity may provide favorable epithelial cell populations. Dermal papilla cells sustaining intrinsic hair inductive capacity, putative dermal papilla precursor cells in the dermal sheath/neonatal dermis or trichogenic dermal cells derived from undifferentiated stem/progenitor cells are promising candidates as hair inductive dermal cells. The most established protocol for in vivo hair follicle reconstitution is co-grafting of epithelial and mesenchymal components into immunodeficient mice. In theory, combination of individually optimized cellular components of respective lineages should elicit most intensive EMIs to form hair follicles. Still, EMIs can be further ameliorated by the modulation of non-cell autonomous conditions, including cell compartmentalization to replicate the positional relationship in vivo and humanization of host environment by preparing human stromal bed. These approaches may not always synergistically intensify EMIs, however, step-by-step investigation probing optimal combinations should maximally enhance EMIs to achieve successful human hair follicle bioengineering.
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Affiliation(s)
- Manabu Ohyama
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan.
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18
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Breitkopf T, Leung G, Yu M, Wang E, McElwee KJ. The basic science of hair biology: what are the causal mechanisms for the disordered hair follicle? Dermatol Clin 2012; 31:1-19. [PMID: 23159172 DOI: 10.1016/j.det.2012.08.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A hair disorder can be difficult to define, but patients are typically motivated to seek treatment when their hair growth patterns are significantly different from their cultural group or when growth patterns change significantly. The causes of hair disorders are many and varied, but fundamentally the disorder is a consequence of aberrant alterations of normal hair biology. The potential trigger factors for hair disorders can be attributed to inflammation, genetics, the environment, or hormones, of which the relative contributions vary for different diagnoses, between individuals, and over time. This article discusses the causal mechanisms for the disordered hair follicle.
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Affiliation(s)
- Trisia Breitkopf
- Department of Dermatology and Skin Science, The University of British Columbia, 835 West Tenth Avenue, Vancouver, BC, Canada
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19
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Driskell RR, Clavel C, Rendl M, Watt FM. Hair follicle dermal papilla cells at a glance. J Cell Sci 2011; 124:1179-82. [PMID: 21444748 DOI: 10.1242/jcs.082446] [Citation(s) in RCA: 282] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Ryan R Driskell
- Laboratory for Epidermal Stem Cell Biology, Wellcome Trust Centre for Stem Cell Research, University of Cambridge, Cambridge CB2 1QR, UK
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20
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Leung MC, Sutton CW, Fenton DA, Tobin DJ. Trichohyalin is a Potential Major Autoantigen in Human Alopecia Areata. J Proteome Res 2010; 9:5153-63. [PMID: 20722389 DOI: 10.1021/pr100422u] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Man Ching Leung
- Centre for Skin Sciences, School of Life Sciences, University of Bradford, Bradford, West Yorkshire, United Kingdom BD7 1DP, Institute of Cancer Therapeutics, University of Bradford, Bradford, West Yorkshire, United Kingdom, and St. Thomas’s Hospital, St. John’s Institute of Dermatology, London, United Kingdom
| | - Chris W. Sutton
- Centre for Skin Sciences, School of Life Sciences, University of Bradford, Bradford, West Yorkshire, United Kingdom BD7 1DP, Institute of Cancer Therapeutics, University of Bradford, Bradford, West Yorkshire, United Kingdom, and St. Thomas’s Hospital, St. John’s Institute of Dermatology, London, United Kingdom
| | - David A. Fenton
- Centre for Skin Sciences, School of Life Sciences, University of Bradford, Bradford, West Yorkshire, United Kingdom BD7 1DP, Institute of Cancer Therapeutics, University of Bradford, Bradford, West Yorkshire, United Kingdom, and St. Thomas’s Hospital, St. John’s Institute of Dermatology, London, United Kingdom
| | - Desmond J. Tobin
- Centre for Skin Sciences, School of Life Sciences, University of Bradford, Bradford, West Yorkshire, United Kingdom BD7 1DP, Institute of Cancer Therapeutics, University of Bradford, Bradford, West Yorkshire, United Kingdom, and St. Thomas’s Hospital, St. John’s Institute of Dermatology, London, United Kingdom
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21
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De novo production of dermal papilla cells during the anagen phase of the hair cycle. J Invest Dermatol 2010; 130:2664-6. [PMID: 20574444 DOI: 10.1038/jid.2010.176] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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22
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Qiao J, Zawadzka A, Philips E, Turetsky A, Batchelor S, Peacock J, Durrant S, Garlick D, Kemp P, Teumer J. Hair follicle neogenesis induced by cultured human scalp dermal papilla cells. Regen Med 2009; 4:667-76. [PMID: 19761392 DOI: 10.2217/rme.09.50] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
AIM To develop a method by which human hair follicle dermal papilla (DP) cells can be expanded in vitro while preserving their hair-inductive potential for use in follicular cell implantation, a cellular therapy for the treatment of hair loss. MATERIALS & METHODS DP cells were isolated from scalp hair follicles in biopsies from human donors. DP cell cultures were established under conditions that preserved their hair-inductive potential and allowed for significant expansion. The hair-inductive potential of cells cultured for approximately 36 doublings was tested in an in vivo flap-graft model. In some experiments, DiI was used to label cells prior to grafting. RESULTS Under the culture conditions developed, cultures established from numerous donors reproducibly resulted in an expansion that averaged approximately five population doublings per passage. Furthermore, the cells consistently induced hair formation in an in vivo graft assay. Grafted DP cells appeared in DP structures of newly formed hairs, as well as in the dermal sheath and in the dermis surrounding follicles. Induced hair follicles persisted and regrew after being plucked 11 months after grafting. CONCLUSION A process for the propagation of human DP cells has been developed that provides significant expansion of cells and maintenance of their hair-inductive capability, overcoming a major technical obstacle in the development of follicular cell implantation as a treatment for hair loss.
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Affiliation(s)
- Jizeng Qiao
- Intercytex Ltd, 175E New Boston Street, Woburn, MA 01801, USA
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23
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Lau K, Paus R, Tiede S, Day P, Bayat A. Exploring the role of stem cells in cutaneous wound healing. Exp Dermatol 2009; 18:921-33. [PMID: 19719838 DOI: 10.1111/j.1600-0625.2009.00942.x] [Citation(s) in RCA: 186] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The skin offers a perfect model system for studying the wound healing cascade, which involves a finely tuned interplay between several cell types, pathways and processes. The dysregulation of these factors may lead to wound healing disorders resulting in chronic wounds, as well as abnormal scars such as hypertrophic and keloid scars. As the contribution of stem cells towards tissue regeneration and wound healing is increasingly appreciated, a rising number of stem cell therapies for cutaneous wounds are currently under development, encouraged by emerging preliminary findings in both animal models and human studies. However, we still lack an in-depth understanding of the underlying mechanisms through which stem cells contribute to cutaneous wound healing. The aim of this review is, therefore, to present a critical synthesis of our current understanding of the role of stem cells in normal cutaneous wound healing. In addition to summarizing wound healing principles and related key molecular and cellular players, we discuss the potential participation of different cutaneous stem cell populations in wound healing, and list corresponding stem cells markers. In summary, this review delineates current strategies, future applications, and limitations of stem cell-based or stem cell-targeted therapy in the management of acute and chronic skin wounds.
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Affiliation(s)
- Katherine Lau
- Proteomics Department, Institute of Analytical Sciences, Dortmund, Germany
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24
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Shin M, Larsson LI, Hougaard DM, Fujiwara K. Daunomycin accumulation and induction of programmed cell death in rat hair follicles. Cell Tissue Res 2009; 337:429-38. [DOI: 10.1007/s00441-009-0840-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 06/30/2009] [Indexed: 02/05/2023]
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25
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Zouboulis CC, Adjaye J, Akamatsu H, Moe-Behrens G, Niemann C. Human skin stem cells and the ageing process. Exp Gerontol 2008; 43:986-97. [PMID: 18809487 DOI: 10.1016/j.exger.2008.09.001] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Revised: 08/31/2008] [Accepted: 09/01/2008] [Indexed: 01/09/2023]
Abstract
In healthy individuals, skin integrity is maintained by epidermal stem cells which self-renew and generate daughter cells that undergo terminal differentiation. Despite accumulation of senescence markers in aged skin, epidermal stem cells are maintained at normal levels throughout life. Therefore, skin ageing is induced by impaired stem cell mobilisation or reduced number of stem cells able to respond to proliferative signals. In the skin, existence of several distinct stem cell populations has been reported. Genetic labelling studies detected multipotent stem cells of the hair follicle bulge to support regeneration of hair follicles but not been responsible for maintaining interfollicular epidermis, which exhibits a distinct stem cell population. Hair follicle epithelial stem cells have at least a dual function: hair follicle remodelling in daily life and epidermal regeneration whenever skin integrity is severely compromised, e.g. after burns. Bulge cells, the first adult stem cells of the hair follicle been identified, are capable of forming hair follicles, interfollicular epidermis and sebaceous glands. In addition, -- at least in murine hair follicles -- they can also give rise to non-epithelial cells, indicating a lineage-independent pluripotent character. Multipotent cells (skin-derived precursor cells) are present in human dermis; dermal stem cells represent 0.3% among human dermal foreskin fibroblasts. A resident pool of progenitor cells exists within the sebaceous gland, which is able to differentiate into both sebocytes and interfollicular epidermis. The self-renewal and multi-lineage differentiation of skin stem cells make these cells attractive for ageing process studies but also for regenerative medicine, tissue repair, gene therapy and cell-based therapy with autologous adult stem cells not only in dermatology. In addition, they provide in vitro models to study epidermal lineage selection and its role in the ageing process.
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Affiliation(s)
- Christos C Zouboulis
- Department of Dermatology, Venereology, Allergology and Immunology, Dessau Medical Center, Dessau, Germany.
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26
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Fernandes KJ, Toma JG, Miller FD. Multipotent skin-derived precursors: adult neural crest-related precursors with therapeutic potential. Philos Trans R Soc Lond B Biol Sci 2008; 363:185-98. [PMID: 17282990 PMCID: PMC2605494 DOI: 10.1098/rstb.2006.2020] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We previously made the surprising finding that cultures of multipotent precursors can be grown from the dermis of neonatal and adult mammalian skin. These skin-derived precursors (SKPs) display multi-lineage differentiation potential, producing both neural and mesodermal progeny in vitro, and are an apparently novel precursor cell type that is distinct from other known precursors within the skin. In this review, we begin by placing these findings within the context of the rapidly evolving stem cell field. We then describe our recent efforts focused on understanding the developmental biology of SKPs, discussing the idea that SKPs are neural crest-related precursors that (i) migrate into the skin during embryogenesis, (ii) persist within a specific dermal niche, and (iii) play a key role in the normal physiology, and potentially pathology, of the skin. We conclude by highlighting some of the therapeutic implications and unresolved questions raised by these studies.
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Affiliation(s)
- Karl J.L Fernandes
- Programs in Developmental Biology, University of TorontoToronto, Ontario, Canada M5G 1X8
- Programs in Cancer Research, University of TorontoToronto, Canada M5G 1X8
| | - Jean G Toma
- Programs in Developmental Biology, University of TorontoToronto, Ontario, Canada M5G 1X8
| | - Freda D Miller
- Programs in Developmental Biology, University of TorontoToronto, Ontario, Canada M5G 1X8
- Programs in Brain and Behaviour, University of TorontoToronto, Canada M5G 1X8
- Department of Molecular and Medical Genetics, University of TorontoToronto, Canada M5G 1X8
- Department of Physiology, University of TorontoToronto, Canada M5G 1X8
- Author for correspondence ()
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27
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Tiede S, Kloepper JE, Bodò E, Tiwari S, Kruse C, Paus R. Hair follicle stem cells: walking the maze. Eur J Cell Biol 2007; 86:355-76. [PMID: 17576022 DOI: 10.1016/j.ejcb.2007.03.006] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Revised: 03/20/2007] [Accepted: 03/21/2007] [Indexed: 12/17/2022] Open
Abstract
The discovery of epithelial stem cells (eSCs) in the bulge region of the outer root sheath of hair follicles in mice and man has encouraged research into utilizing the hair follicle as a therapeutic source of stem cells (SCs) for regenerative medicine, and has called attention to the hair follicle as a highly instructive model system for SC biology. Under physiological circumstances, bulge eSCs serve as cell pool for the cyclic regeneration of the anagen hair bulb, while they can also regenerate the sebaceous gland and the epidermis after injury. More recently, melanocyte SCs, nestin+, mesenchymal and additional, as yet ill-defined "stem cell" populations, have also been identified in or immediately adjacent to the hair follicle epithelium, including in the specialized hair follicle mesenchyme (connective tissue sheath), which is crucial to wound healing. Thus the hair follicle and its adjacent tissue environment contain unipotent, multipotent, and possibly even pluripotent SC populations of different developmental origin. It provides an ideal model system for the study of central issues in SC biology such as plasticity and SC niches, and for the identification of reliable, specific SC markers, which distinguish them from their immediate progeny (e.g. transient amplifying cells). The current review attempts to provide some guidance in this growing maze of hair follicle-associated SCs and their progeny, critically reviews potential or claimed hair follicle SC markers, highlights related differences between murine and human hair follicles, and defines major unanswered questions in this rapidly advancing field.
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Affiliation(s)
- Stephan Tiede
- Department of Dermatology, University Hospital Schleswig-Holstein, University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany
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Boivin WA, Jiang H, Utting OB, Hunt DWC. Influence of interleukin-1α on androgen receptor expression and cytokine secretion by cultured human dermal papilla cells. Exp Dermatol 2006; 15:784-93. [PMID: 16984260 DOI: 10.1111/j.1600-0625.2006.00462.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Dermal papilla cells (DPC) control the growth character of the hair follicle through their elaboration of mitogenic factors and extracellular matrix components. Further, the dermal papilla is a primary site of androgen action in the hair follicle. Interleukin-1alpha (IL-1alpha) is prominent in skin wounding and inflammatory responses although regarded as a negative hair growth regulator. We studied the effect of IL-1alpha and the potent androgen 5alpha-dihydrotestosterone (DHT) on the expression of the androgen receptor (AR) and various factors secreted by cultured human temporal scalp DPC. IL-1alpha triggered cellular changes consistent with nuclear factor-kappaB pathway activation as well as reduced AR mRNA and protein expression levels for DHT-stimulated DPC. This cytokine also increased DPC supernatant keratinocyte growth factor (KGF), vascular endothelial growth factor (VEGF), IL-8 and granulocyte-macrophage colony-stimulating factor (GM-CSF) concentrations. IL-1alpha did not influence DPC supernatant levels of transforming growth factor-beta1, a negative hair growth regulator. The stimulatory effect of IL-1alpha on DPC VEGF, GM-CSF, KGF, and IL-8 expression was also evident at the mRNA level for these cytokines. IL-1alpha also increased mRNA transcript levels of protease-nexin-1, a secreted serine protease inhibitor expressed in the dermal papilla of anagen-stage hair follicles. Although DHT did not affect supernatant cytokine concentrations, the androgen altered mRNA transcript levels of several factors for DPC co-stimulated with IL-1alpha. In consideration of its in vitro activity profile, IL-1alpha may be an important modifier of dermal papilla activity as well as potentially influence androgen-regulated gene expression in DPC.
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Affiliation(s)
- Wendy A Boivin
- Scientific Affairs: Dermatology, QLT Inc., 887 Great Northern Way, Vancouver, British Columbia, Canada
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Abstract
For many decades, androgens have dominated endocrine research in hair growth control. Androgen metabolism and the androgen receptor currently are the key targets for systemic, pharmacological hair growth control in clinical medicine. However, it has long been known that estrogens also profoundly alter hair follicle growth and cycling by binding to locally expressed high-affinity estrogen receptors (ERs). Besides altering the transcription of genes with estrogen-responsive elements, 17beta-estradiol (E2) also modifies androgen metabolism within distinct subunits of the pilosebaceous unit (i.e., hair follicle and sebaceous gland). The latter displays prominent aromatase activity, the key enzyme for androgen conversion to E2, and is both an estrogen source and target. Here, we chart the recent renaissance of estrogen research in hair research; explain why the hair follicle offers an ideal, clinically relevant test system for studying the role of sex steroids, their receptors, and interactions in neuroectodermal-mesodermal interaction systems in general; and illustrate how it can be exploited to identify novel functions and signaling cross talks of ER-mediated signaling. Emphasizing the long-underestimated complexity and species-, gender-, and site-dependence of E2-induced biological effects on the hair follicle, we explore targets for pharmacological intervention in clinically relevant hair cycle manipulation, ranging from androgenetic alopecia and hirsutism via telogen effluvium to chemotherapy-induced alopecia. While defining major open questions, unsolved clinical challenges, and particularly promising research avenues in this area, we argue that the time has come to pay estrogen-mediated signaling the full attention it deserves in future endocrinological therapy of common hair growth disorders.
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Affiliation(s)
- Ulrich Ohnemus
- Department of Dermatology, University Hospital Schleswig-Holstein, Campus Lübeck, University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany
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Wu JJ, Zhu TY, Lu YG, Liu RQ, Mai Y, Cheng B, Lu ZF, Zhong BY, Tang SQ. Hair follicle reformation induced by dermal papilla cells from human scalp skin. Arch Dermatol Res 2006; 298:183-90. [PMID: 16897077 DOI: 10.1007/s00403-006-0686-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Revised: 05/01/2006] [Accepted: 06/30/2006] [Indexed: 12/16/2022]
Abstract
To investigate the possibility of hair follicle reformation induced by dermal papilla cells in vivo and in vitro. Dermal papilla cells, dermal sheath cells obtained from human scalp skin by enzyme digestion were mixed with collagen to form mesenchymal cell-populated collagen gels. Superior and inferior epithelial cells and bulb matrical cells were then cultured on these gels by organotypic culture to recombine bilayer artificial skins. Dermal papilla cells and outer root sheath keratinocytes were mingled together and transplanted under subcutaneous tissue of the dorsal skin of nude mice. The results of histologic examination was observed with HE stain. These recombinants by organotypic culture all reformed bilayer structure like nature skin. Hair follicle-like structure reformation was found in dermal sheath cell-populated collagen gel when combined with superior or inferior epithelial cells. Dermal papilla cells also induced superior and inferior epithelial cells to form hair follicle on nude mice. Low passage dermal papilla cells mixed with hair follicle epithelial cells reformed many typical hair follicle structures and produced hair fibres after transplantation on nude mice. The dermal part of hair follicle, such as dermal papilla cells and dermal sheath cells, has the ability to induce hair follicle formation by interaction with the epithelial cells of hair follicle.
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Affiliation(s)
- Jin-Jin Wu
- Department of Dermatology, Institute of Battle Surgery, Daping Hospital, The Third Military Medical University, Chongqing 400042, People's Republic of China.
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Kauser S, Slominski† A, Wei ET, Tobin DJ. Modulation of the human hair follicle pigmentary unit by corticotropin-releasing hormone and urocortin peptides. FASEB J 2006; 20:882-95. [PMID: 16675846 PMCID: PMC1472637 DOI: 10.1096/fj.05-5257com] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Human skin is a local source of corticotropin-releasing hormone (CRH) and expresses CRH and CRH receptors (CRH-R) at mRNA and protein levels. Epidermal melanocytes respond to CRH by induction of cAMP with up-regulation of pro-opiomelanocortin gene expression and subsequent production of adrenocorticotropin hormone. However, the role of CRH/CRH-R in melanocyte biology is complicated by the significant heterogeneity of cutaneous melanocyte subpopulations, from continuously active and UV-responsive melanocytes in epidermis to UV nonresponsive, hair growth cycle-coupled melanogenesis in hair follicles. In the present study we report that normal human scalp hair follicle melanocytes express CRH at the mRNA level. Furthermore, CRH, urocortin and CRH-R 1 and 2 were differentially expressed in follicular melanocytes, fibroblasts, and keratinocytes depending on anatomic location and differentiation status in situ and in vitro. Stimulation of follicular melanocytes with CRH and CRH peptides, modified for selectivity for CRH-R1 and/or CRH-R2, variably induced cell melanogenesis, dendricity, and proliferation. CRH-peptides also stimulated the expression and activity of Tyrosinase, and expression of Tyrosinase-related protein-1 and-2. However, a modified urocortin peptide highly selective for CRH-R2 down-regulated melanocyte differentiation phenotype. This study indicates that CRH peptides can differentially influence hair follicle melanocyte behavior not only via CRH-R1 signaling but also by complex cross-talk between CRH-R1 and CRH-R2.
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Affiliation(s)
- Sobia Kauser
- Department of Biomedical Sciences, University of Bradford, West Yorkshire, UK; Department of Pathology and Laboratory Medicine, University of Tennessee HSC, Memphis, Tennessee, USA; and
| | | | - Edward T. Wei
- School of Public Health, University of California, Berkeley, California, USA
| | - Desmond J. Tobin
- Department of Biomedical Sciences, University of Bradford, West Yorkshire, UK; Department of Pathology and Laboratory Medicine, University of Tennessee HSC, Memphis, Tennessee, USA; and
- Correspondence: Department of Biomedical Sciences, University of Bradford, Bradford, West Yorkshire, BD7 1DP, UK. E-mail:
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Selleri S, Arnaboldi F, Vizzotto L, Balsari A, Rumio C. Epithelium-mesenchyme compartment interaction and oncosis on chemotherapy-induced hair damage. J Transl Med 2004; 84:1404-17. [PMID: 15378070 DOI: 10.1038/labinvest.3700170] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
It is known that chemotherapy induces alopecia in humans, with important psychological and social implications in spite of its reversibility. Among chemotherapeutic drugs, anthracyclines are widely used, yet cause severe alopecia. One of the causes for the elevated sensibility of hair follicles to anthracyclines, and to drugs in general, is the high proliferation rate of follicular epithelium and the long duration of the growth phase (up to 7 years in humans). To clarify the mechanism of anthracycline toxicity, we used a rat model and focused our attention on the morphological alterations in hair follicles induced by doxorubicin. We observed the progression of hair follicle degeneration in the epithelial and mesenchymal compartments until alopecia arose, by both light and electron microscopy. As a first sign of damage, significant apoptosis was detected in the proximal perifollicular connective tissue sheath and sporadically in the matrix, near the interface between matrix and follicular papilla. We propose the apoptotic remodeling of the mesenchymal compartment as a process that is fundamental to the progression of events leading to alopecia. Regarding the epithelial compartment, it is important to note that oncosis was observed in a large number of follicular cells in the outer root sheath during the last stages of hair follicle regression. This indicates that oncosis is involved in a major way in the damage of epithelial cells.
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Affiliation(s)
- Silvia Selleri
- Department of Human Morphology, Università degli Studi di Milano, Milan, Italy
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