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Kamishima T, Hirabe C, Myint KZY, Taguchi J. Divergent progression pathways in male androgenetic alopecia and female pattern hair loss: Trichoscopic perspectives. J Cosmet Dermatol 2024; 23:1828-1839. [PMID: 38189587 DOI: 10.1111/jocd.16177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/22/2023] [Accepted: 12/28/2023] [Indexed: 01/09/2024]
Abstract
BACKGROUND Despite similarities in progressive miniaturization of hair follicles and transition of terminal hairs to vellus hairs, insufficient trichoscopic comparisons between male androgenetic alopecia (MAGA) and female pattern hair loss (FPHL) hinder our ability to select effective treatments. AIM Our study aimed to explore gender-specific trichoscopic characteristics of MAGA and FPHL, while formulating hypotheses regarding the progression of these conditions across clinical stages. METHODS We classified 126 male MAGA subjects using Hamilton-Norwood Classification and 57 FPHL subjects using adopted Sinclair Scale. Subsequently, we analyzed nine trichoscopic factors divided into three categories: hair-diameter related, hair-number per follicular unit related, and hair density related factors. RESULTS Of the nine quantitative trichoscopic factors, hair-diameter and hair-number per follicular unit showed strong correlations with clinical stages in both genders. Hair density, a common trichoscopic factor for hair loss evaluation, weakly correlated with clinical stages in FPHL, but not at all in MAGA. In addition, MAGA was characterized by a progressive reduction in hair-diameter, followed by a reduction in hair-number per follicular unit. FPHL, on the contrary, showed the opposite progression. CONCLUSIONS Trichoscopic factors vary with disease severity in a gender-specific manner. Our research highlights that MAGA and FPHL involve two distinct streams: hair-diameter decreasing by hair follicle miniaturization (Stream 1), and hair-number per follicular unit decreasing by hair follicle tri-lineage niche dysfunction (Stream 2). MAGA typically starts from Stream 1 to Stream 2, while FPHL starts from Stream 2. These diverse progression pathways underscore the importance of personalized treatment approaches.
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Affiliation(s)
- Tomoko Kamishima
- Department of Dermatology, Tokyo Midtown Skin/Aesthetic Clinic Noage, Tokyo, Japan
| | - Chie Hirabe
- Department of Dermatology, Tokyo Midtown Skin/Aesthetic Clinic Noage, Tokyo, Japan
| | - Khin Zay Yar Myint
- Tokyo Midtown Center for Advanced Medical Science and Technology, Tokyo, Japan
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Lee JH, Choi S. Deciphering the molecular mechanisms of stem cell dynamics in hair follicle regeneration. Exp Mol Med 2024; 56:110-117. [PMID: 38182654 PMCID: PMC10834421 DOI: 10.1038/s12276-023-01151-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 10/24/2023] [Accepted: 11/01/2023] [Indexed: 01/07/2024] Open
Abstract
Hair follicles, which are connected to sebaceous glands in the skin, undergo cyclic periods of regeneration, degeneration, and rest throughout adult life in mammals. The crucial function of hair follicle stem cells is to maintain these hair growth cycles. Another vital aspect is the activity of melanocyte stem cells, which differentiate into melanin-producing melanocytes, contributing to skin and hair pigmentation. Sebaceous gland stem cells also have a pivotal role in maintaining the skin barrier by regenerating mature sebocytes. These stem cells are maintained in a specialized microenvironment or niche and are regulated by internal and external signals, determining their dynamic behaviors in homeostasis and hair follicle regeneration. The activity of these stem cells is tightly controlled by various factors secreted by the niche components around the hair follicles, as well as immune-mediated damage signals, aging, metabolic status, and stress. In this study, we review these diverse stem cell regulatory and related molecular mechanisms of hair regeneration and disease conditions. Molecular insights would provide new perspectives on the disease mechanisms as well as hair and skin disorder treatment.
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Affiliation(s)
- Jung Hyun Lee
- Department of Dermatology, School of Medicine, University of Washington, Seattle, WA, 98109, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, 98109, USA
| | - Sekyu Choi
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
- Medical Science and Engineering, School of Convergence Science and Technology, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
- Institute for Convergence Research and Education in Advanced Technology (I_CREATE), Yonsei University, Incheon, 21983, Republic of Korea.
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Redmond LC, Limbu S, Farjo B, Messenger AG, Higgins CA. Male pattern hair loss: Can developmental origins explain the pattern? Exp Dermatol 2023; 32:1174-1181. [PMID: 37237288 PMCID: PMC10946844 DOI: 10.1111/exd.14839] [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: 12/02/2022] [Revised: 05/04/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023]
Abstract
Male pattern hair loss (MPHL), also referred to as male androgenetic alopecia (AGA) is the most common type of non-scarring progressive hair loss, with 80% of men suffering from this condition in their lifetime. In MPHL, the hair line recedes to a specific part of the scalp which cannot be accurately predicted. Hair is lost from the front, vertex, and the crown, yet temporal and occipital follicles remain. The visual effect of hair loss is due to hair follicle miniaturisation, where terminal hair follicles become dimensionally smaller. Miniaturisation is also characterised by a shortening of the growth phase of the hair cycle (anagen), and a prolongation of the dormant phase (kenogen). Together, these changes result in the production of thinner and shorter hair fibres, referred to as miniaturised or vellus hairs. It remains unclear why miniaturisation occurs in this specific pattern, with frontal follicles being susceptible while occipital follicles remain in a terminal state. One main factor we believe to be at play, which will be discussed in this viewpoint, is the developmental origin of the skin and hair follicle dermis on different regions of the scalp.
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Affiliation(s)
| | - Summik Limbu
- Department of BioengineeringImperial College LondonLondonUK
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Mysore V, Kumaresan M, Dashore S, Venkatram A. Combination and Rotational Therapy in Androgenetic Alopecia. J Cutan Aesthet Surg 2023; 16:71-80. [PMID: 37554681 PMCID: PMC10405544 DOI: 10.4103/jcas.jcas_212_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023] Open
Abstract
Management of androgenetic alopecia is a challenge because of its long course, need for continuous treatment, and potential adverse effects of the therapies. In order to enhance efficacy, minimize side effects, and ensure patient compliance, the authors propose a scheme for using combination treatments with a rotational scheme, based on current evidence for efficacy, pharmacokinetic properties, convenience of administration over long term, side effect profile, and patient acceptance.
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Affiliation(s)
- Venkatram Mysore
- Venkat Center for Advanced Skin ENT and Plastic Surgery and Postgraduate Training, Bengaluru, Karnataka, India
| | - Muthuvel Kumaresan
- Cutis Skin Clinic & Hair Transplant Center, Coimbatore, Tamil Nadu, India
| | - Shuken Dashore
- Hair Transplant & Laser Center, Indore, Madhya Pradesh, India
| | - Aniketh Venkatram
- Venkat Center for Advanced Skin ENT and Plastic Surgery and Postgraduate Training, Bengaluru, Karnataka, India
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5
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Ezure T, Amano S, Matsuzaki K. Quantitative characterization of 3D structure of vellus hair arrector pili muscles by micro CT. Skin Res Technol 2022; 28:689-694. [PMID: 35726958 PMCID: PMC9907649 DOI: 10.1111/srt.13168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 05/03/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Vellus hair is the fine, wispy hair found over most of the body surface, and the arrector pili muscles (hair muscle) serve to raise these hairs. Hair muscles are also critical for skin regeneration, contributing to the maintenance of stem cells in epidermis and hair follicles. However, little is known about their fundamental properties, especially their structure, because of the limitations of conventional two-dimensional histological analysis. OBJECTIVES We aimed to quantitatively characterize the structure of vellus hair muscles by establishing a method to visualize the 3D structure of hair muscle. METHODS We observed young female abdominal skin specimens by means of X-ray micro CT and identified hair muscles in each cross-sectional CT image. We then digitally reconstructed the 3D structure of the hair muscles on computer (digital-3D skin), and numerically evaluated their structural parameters. RESULTS Vellus hair muscles were clearly distinguished from the surrounding dermal layer in X-ray micro CT images and were digitally reconstructed in 3D from those images for quantification of the structural parameters. The mean value of number of divisions of vellus hair muscles was 1.6, mean depth was 943.6 μm from the skin surface, mean angle to the skin surface was 28.8 degrees, and mean length was 1657.9 μm. These values showed relatively little variation among subjects. The mean muscle volume was approximately 20 million μm3 but showed greater variability than the other parameters. CONCLUSION Digital-3D skin technology is a powerful approach to understand the tiny but complex 3D structure of vellus hair muscles. The fundamental nature of vellus hair muscles was characterized in terms of their 3D structural parameters, including number of divisions, angle to the skin surface, depth, and volume.
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Affiliation(s)
- Tomonobu Ezure
- MIRAI Technology Institute, Shiseido Co., Ltd., Yokohama, Japan
| | - Satoshi Amano
- MIRAI Technology Institute, Shiseido Co., Ltd., Yokohama, Japan
| | - Kyoichi Matsuzaki
- Department of Plastic and Reconstructive Surgery, School of Medicine, International University of Health and Welfare, Narita, Japan
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Watson VE, Faniel ML, Kamili NA, Krueger LD, Zhu C. Immune-mediated alopecias and their mechanobiological aspects. Cells Dev 2022; 170:203793. [PMID: 35649504 PMCID: PMC10681075 DOI: 10.1016/j.cdev.2022.203793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/24/2022] [Indexed: 02/06/2023]
Abstract
Alopecia is a non-specific term for hair loss clinically diagnosed by the hair loss pattern and histological analysis of patient scalp biopsies. The immune-mediated alopecia subtypes, including alopecia areata, lichen planopilaris, frontal fibrosing alopecia, and central centrifugal cicatricial alopecia, are common, significant forms of alopecia subtypes. For example, alopecia areata is the most common autoimmune disease with a lifetime incidence of approximately 2% of the world's population. In this perspective, we discuss major results from studies of immune-mediated alopecia subtypes. These studies suggest the key event in disease onset as the collapse in immune privilege, which alters the hair follicle microenvironment, e.g., upregulation of major histocompatibility complex molecules and increase of cytokine production, and results in immune cell infiltration, inflammatory responses, and damage of hair follicles. We note that previous studies have established that the hair follicle has a complex mechanical microenvironment, which may regulate the function of not only tissue cells but also immune cell infiltrates. This suggests a potential for mechanobiology to contribute to alopecia research by adding new methods, new approaches, and new ways of thinking, which is missing in the existing literature. To fill this a gap in the alopecia research space, we develop a mechanobiological hypothesis that alterations in the hair follicle microenvironment, specifically in the mechanically responsive tissues and cells, partially due to loss of immune privilege, may be contributors to disease pathology. We further focus our discussion on the potential for applying mechanoimmunology to the study of T cell infiltrates in the hair follicle, as they are considered primary contributors to alopecia pathology. To establish the connection between the mechanoimmunological hypothesis and immune-mediated alopecia subtypes, we discuss what is known about the role of T cells in immune-mediated alopecia subtypes, using the most extensively studied AA as our model.
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Affiliation(s)
- Valencia E Watson
- Wallace H. Coulter Department of Biomedical Engineering, USA; Bioengineering PhD Program, USA; Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Makala L Faniel
- Wallace H. Coulter Department of Biomedical Engineering, USA; Bioengineering PhD Program, USA; Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, USA
| | | | - Loren D Krueger
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA.
| | - Cheng Zhu
- Wallace H. Coulter Department of Biomedical Engineering, USA; Bioengineering PhD Program, USA; Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, USA.
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7
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Comment on scalp neuropathy in androgenetic alopecia. J Am Acad Dermatol 2022; 87:e81. [DOI: 10.1016/j.jaad.2022.03.065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/04/2022] [Accepted: 03/08/2022] [Indexed: 11/22/2022]
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8
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Sadgrove NJ. The ‘bald’ phenotype (androgenetic alopecia) is caused by the high glycaemic, high cholesterol and low mineral ‘western diet’. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.06.056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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9
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Ten B, Kaya Tİ, Balcı Y, Esen K, Temel G, Türsen Ü, Yılmaz MA. The place of B-mode ultrasonography, shear-wave elastography, and superb microvascular imaging in the pre-diagnosis of androgenetic alopecia. J Cosmet Dermatol 2021; 21:2962-2970. [PMID: 34587657 DOI: 10.1111/jocd.14488] [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: 08/26/2021] [Accepted: 09/14/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE Androgenetic alopecia (AGA) is the most common cause of hair loss in males. Physical examination and history are the most important examinations in diagnosis of the disease. As yet, there is no diagnostic method to be able to determine which individuals will develop AGA. Shear-wave elastography (SWE) is a novel diagnostic tool, which can evaluate tissue stiffness. Superb microvascular imaging (SMI) can determine low flow in microvessels. The aim of the current study was to determine whether or not AGA would develop in individuals with normal hair and a family history of AGA using B-mode US, SMI, and SWE. METHODS The study included 26 patients clinically diagnosed with AGA and a control group of 26 volunteers. RESULTS Thickness with the distance from the epidermis to the calvarium (ECD) on the hairline and cranial subcutaneous tissue thickness (CSTD) were determined to be statistically significantly thinner in the AGA group than in the control group (p < 0.0001). For the differentiation of the AGA patients, the cutoff value was determined to be 5.5 mm for ECD and 4.05 mm for CSTD. The cranial epidermis-dermis (CED) stiffness values both as meter/second (m/s) and kilopascals (kPa) were statistically significantly lower in the AGA patients than in the control group (p < 0.0001). The cutoff values were 6.075 as m/s and 104.4 as kPa. CONCLUSIONS The results of this study demonstrated that differentiation could be made of individuals before the development of AGA from normal healthy individuals with CSTD measurement on B-mode US and CED stiffness measurement on SWE.
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Affiliation(s)
- Barış Ten
- Department of Radiology, Mersin University Faculty of Medicine, Mersin, Turkey
| | - Tamer İrfan Kaya
- Department of Dermatology, Mersin University Faculty of Medicine, Mersin, Turkey
| | - Yüksel Balcı
- Department of Radiology, Mersin University Faculty of Medicine, Mersin, Turkey
| | - Kaan Esen
- Department of Radiology, Mersin University Faculty of Medicine, Mersin, Turkey
| | - Gülhan Temel
- Department of Biostatistics, Mersin University Faculty of Medicine, Mersin, Turkey
| | - Ümit Türsen
- Department of Dermatology, Mersin University Faculty of Medicine, Mersin, Turkey
| | - Mustafa Anıl Yılmaz
- Department of Dermatology, Mersin University Faculty of Medicine, Mersin, Turkey
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Willems A, Sinclair R. Alopecias in humans: biology, pathomechanisms and emerging therapies. Vet Dermatol 2021; 32:596-e159. [PMID: 34431565 DOI: 10.1111/vde.13014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/19/2021] [Accepted: 06/23/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND The hair follicle is a complete mini-organ with a complex biology. Recent discoveries have shed light on the pathogenesis and genetic basis of a number of hair loss conditions, offering novel treatment alternatives. OBJECTIVE To explore the biology and physiology of hair growth, the pathomechanism behind alopecias and emerging therapies. CONCLUSION AND CLINICAL IMPORTANCE Hair growth is influenced by numerous physiological moderators. Greater understanding of the biology and physiology of the hair follicle and the pathomechanisms of hair disease facilitates development of targeted treatments. Sublingual minoxidil is a promising therapy in humans where optimised drug delivery enhances efficacy and reduces systemic adverse effects. Janice kinase inhibitors, which disrupt the inflammatory cascade, help maintain the hair follicle, preserve immune privilege, and regrow hair in alopecia areata. As the pathomechanisms of other forms of alopecia become better understood, new targeted therapies with greater efficacy will emerge.
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Affiliation(s)
- Anneliese Willems
- Sinclair Dermatology, 2 Wellington Parade, East Melbourne, VIC, 3002, Australia
| | - Rodney Sinclair
- Sinclair Dermatology, 2 Wellington Parade, East Melbourne, VIC, 3002, Australia.,Department of Medicine, Alan Gilbert Building University of Melbourne, 161 Barry St, Melbourne, VIC, 3010, Australia
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Kutlu Ö, Metin A. Systemic dexpanthenol as a novel treatment for female pattern hair loss. J Cosmet Dermatol 2020; 20:1325-1330. [PMID: 32960484 DOI: 10.1111/jocd.13729] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 09/08/2020] [Indexed: 01/21/2023]
Abstract
BACKGROUND There are only a few drugs that have been used for the treatment of female pattern hair loss (FPHL). AIMS Through use of the Dermatologic Life Quality Index (DLQI) and a modified hair growth questionnaire, we aimed to evaluate the effect of dexpanthenol (DXP) as a new option for FPHL. METHODS Women who received 500 mg intramuscular DXP weekly for FPHL were included in this study. They were evaluated in terms of DLQI and laboratory characteristics, before and after DXP treatment, and were examined with a modified hair growth questionnaire. RESULTS Overall satisfaction with the appearance of the hair was described by the patients as 57.1% " I am satisfied," 28.6% "I am very satisfied," and 14.3% "I am neutral (neither satisfied nor dissatisfied)." There was a statistical difference between the mean DLQI scores before and after DXP treatment (P < .001). No statistical difference was found in the laboratory characteristics of the patients before and after DXP treatment (P > 0.05). No side effect was reported during DXP treatment. CONCLUSION Dexpanthenol is a safe and novel drug that may increase the quality of life in patients with FPHL.
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Affiliation(s)
- Ömer Kutlu
- Department of Dermatology and Venereology, School of Medicine, Uşak University, Uşak, Turkey
| | - Ahmet Metin
- Department of Dermatology and Venereology I School of Medicine, Yildirim Beyazit University, Ankara, Turkey
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Shwartz Y, Gonzalez-Celeiro M, Chen CL, Pasolli HA, Sheu SH, Fan SMY, Shamsi F, Assaad S, Lin ETY, Zhang B, Tsai PC, He M, Tseng YH, Lin SJ, Hsu YC. Cell Types Promoting Goosebumps Form a Niche to Regulate Hair Follicle Stem Cells. Cell 2020; 182:578-593.e19. [PMID: 32679029 DOI: 10.1016/j.cell.2020.06.031] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 04/06/2020] [Accepted: 06/18/2020] [Indexed: 02/08/2023]
Abstract
Piloerection (goosebumps) requires concerted actions of the hair follicle, the arrector pili muscle (APM), and the sympathetic nerve, providing a model to study interactions across epithelium, mesenchyme, and nerves. Here, we show that APMs and sympathetic nerves form a dual-component niche to modulate hair follicle stem cell (HFSC) activity. Sympathetic nerves form synapse-like structures with HFSCs and regulate HFSCs through norepinephrine, whereas APMs maintain sympathetic innervation to HFSCs. Without norepinephrine signaling, HFSCs enter deep quiescence by down-regulating the cell cycle and metabolism while up-regulating quiescence regulators Foxp1 and Fgf18. During development, HFSC progeny secretes Sonic Hedgehog (SHH) to direct the formation of this APM-sympathetic nerve niche, which in turn controls hair follicle regeneration in adults. Our results reveal a reciprocal interdependence between a regenerative tissue and its niche at different stages and demonstrate sympathetic nerves can modulate stem cells through synapse-like connections and neurotransmitters to couple tissue production with demands.
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Affiliation(s)
- Yulia Shwartz
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Meryem Gonzalez-Celeiro
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA; Institute of Molecular Health Sciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Chih-Lung Chen
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei 100, Taiwan
| | - H Amalia Pasolli
- Electron Microscopy Resource Center, The Rockefeller University, New York, NY 10065, USA
| | - Shu-Hsien Sheu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Sabrina Mai-Yi Fan
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei 100, Taiwan
| | - Farnaz Shamsi
- Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - Steven Assaad
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Edrick Tai-Yu Lin
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei 100, Taiwan
| | - Bing Zhang
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Pai-Chi Tsai
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Megan He
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Yu-Hua Tseng
- Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA; Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
| | - Sung-Jan Lin
- Department of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei 100, Taiwan; Department of Dermatology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 100, Taiwan; Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei 100, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei 100, Taiwan.
| | - Ya-Chieh Hsu
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA.
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Qu Q, Shi P, Yi Y, Fan Z, Liu X, Zhu D, Chen J, Ye K, Miao Y, Hu Z. Efficacy of Platelet-rich Plasma for Treating Androgenic Alopecia of Varying Grades. Clin Drug Investig 2020; 39:865-872. [PMID: 31228018 DOI: 10.1007/s40261-019-00806-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND OBJECTIVES Platelet-rich plasma (PRP) has received growing attention as a valuable therapeutic tool in androgenetic alopecia (AGA). However, knowledge regarding specific effectiveness and satisfaction of PRP for different grades of AGA in male pattern hair loss (MPHL) and female pattern hair loss (FPHL) is missing. This study aims to ascertain and compare the efficacy and safety of PRP treatment for different grades of AGA in males and females over 6 months. METHODS In this study, 51 MPHL patients with Norwood-Hamilton stage II-V and 42 FPHL patients with Ludwig stage I to III were enrolled for 6 monthly sessions of PRP injections. A longitudinal analysis was used to compare the hair density, thickness, and hair pull test over 6 months for MPHL and FPHL through generalized estimating equation (GEE) models. Phototrichograms of scalp inflammation and oil secretion, global photographs and overall patient satisfaction were also assessed. RESULTS Consequently, improvement of hair density, hair thickness, hair pull test, the level of scalp inflammation and oil secretion were observed with statistical significance in all stages for both MPHL and FPHL at 6 months. Noteworthy, lower level of alopecia (Grade II, III in MPHL and Grade I in FPHL) had better response to PRP, and also had a better tendency of increment of hair growth than that of high-grade patients with prolonged treatment. CONCLUSIONS PRP injections, as an efficacious and reliable therapy, can be recommended for Grade II and Grade III in MPHL and Grade I in FPHL.
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Affiliation(s)
- Qian Qu
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China
| | - Panli Shi
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China
| | - Yanhua Yi
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China
| | - Zhexiang Fan
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China
| | - Xiaomin Liu
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China
| | - Decong Zhu
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China
| | - Jian Chen
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China
| | - Ke Ye
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China
| | - Yong Miao
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China.
| | - Zhiqi Hu
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, 1838 North Guangzhou AV, Guangzhou, 510515, Guangdong Province, China.
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Adipose Infiltration of the Dermis, Involving the Arrector Pili Muscle, and Dermal Displacement of Eccrine Sweat Coils: New Histologic Observations in Frontal Fibrosing Alopecia. Am J Dermatopathol 2019; 41:492-497. [PMID: 30624243 DOI: 10.1097/dad.0000000000001349] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Frontal fibrosing alopecia (FFA) is an irreversible scarring alopecia, and its incidence has reached epidemic size. Immune privilege collapse of the bulge and epithelial mesenchymal transition play a role in the pathogenesis. We have noted adipose tissue in the dermis in several specimens from FFA. OBJECTIVE Our primary objective was to verify the presence of adipose tissue at the isthmus level in biopsies from FFA. Additional objectives included the presence of deep inflammation and position of the sweat coils. METHODS Eighty-three histologic specimens of FFA diagnosed at the Dermatopathology Laboratory at the Department of Dermatology, University of Miami, within 3 years were evaluated retrospectively. All biopsies were bisected horizontally and assessed at several levels. Sixty biopsies from androgenetic alopecia served as controls. Statistical analysis was performed using the χ test. A P value of 0.05 or less was considered significant. RESULTS Sixty specimens met the inclusion criteria for optimal quality and classic diagnostic features. Seventy percent demonstrated fat tissue infiltration at the isthmus level as clusters of cells or small globules versus 23% of the controls. The fat infiltration in the arrector pili muscle (APM) was present in 55% versus 15% of the controls, and the sweat coils were positioned in the reticular dermis in 43% versus 1.7% of the controls. All results were statistically significant (P < 0.0001). When accounting for the simultaneous presence of any of these 3 variables, 30% of the FFA cases had triple positivity, 61.7% had double positivity, and 75% had at least 1 positive variable versus 0%, 15%, and 10%, respectively, of the controls. CONCLUSION New histologic findings in FFA involve the presence of adipose tissue in the dermis. We believe that the close interaction of the hair follicles and the APM with the adipose tissue may play a role in APM degeneration and in epithelial mesenchymal transition.
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15
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Ho BSY, Ho EXP, Chu CW, Ramasamy S, Bigliardi-Qi M, de Sessions PF, Bigliardi PL. Microbiome in the hair follicle of androgenetic alopecia patients. PLoS One 2019; 14:e0216330. [PMID: 31050675 PMCID: PMC6499469 DOI: 10.1371/journal.pone.0216330] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 04/19/2019] [Indexed: 12/02/2022] Open
Abstract
Androgenetic alopecia is the most common form of hair loss in males. It is a multifactorial condition involving genetic predisposition and hormonal changes. The role of microflora during hair loss remains to be understood. We therefore analyzed the microbiome of hair follicles from hair loss patients and the healthy. Hair follicles were extracted from occipital and vertex region of hair loss patients and healthy volunteers and further dissected into middle and lower compartments. The microbiome was then characterized by 16S rRNA sequencing. Distinct microbial population were found in the middle and lower compartment of hair follicles. Middle hair compartment was predominated by Burkholderia spp. and less diverse; while higher bacterial diversity was observed in the lower hair portion. Occipital and vertex hair follicles did not show significant differences. In hair loss patients, miniaturized vertex hair houses elevated Propionibacterium acnes in the middle and lower compartments while non-miniaturized hair of other regions were comparable to the healthy. Increased abundance of P. acnes in miniaturized hair follicles could be associated to elevated immune response gene expression in the hair follicle.
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Affiliation(s)
- Bryan Siu-Yin Ho
- Experimental Dermatology Group, Institute of Medical Biology, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Eliza Xin Pei Ho
- GERMS Platform for microbial genomics, Genome Institute of Singapore, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Collins Wenhan Chu
- GERMS Platform for microbial genomics, Genome Institute of Singapore, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Srinivas Ramasamy
- Experimental Dermatology Group, Institute of Medical Biology, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Mei Bigliardi-Qi
- Experimental Dermatology Group, Institute of Medical Biology, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Paola Florez de Sessions
- GERMS Platform for microbial genomics, Genome Institute of Singapore, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
| | - Paul Lorenz Bigliardi
- Experimental Dermatology Group, Institute of Medical Biology, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
- YLL School of Medicine, National University of Singapore and National University Hospital System NUHS, Singapore, Singapore
- * E-mail:
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16
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Chu SY, Chou CH, Huang HD, Yen MH, Hong HC, Chao PH, Wang YH, Chen PY, Nian SX, Chen YR, Liou LY, Liu YC, Chen HM, Lin FM, Chang YT, Chen CC, Lee OK. Mechanical stretch induces hair regeneration through the alternative activation of macrophages. Nat Commun 2019; 10:1524. [PMID: 30944305 PMCID: PMC6447615 DOI: 10.1038/s41467-019-09402-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 03/04/2019] [Indexed: 12/28/2022] Open
Abstract
Tissues and cells in organism are continuously exposed to complex mechanical cues from the environment. Mechanical stimulations affect cell proliferation, differentiation, and migration, as well as determining tissue homeostasis and repair. By using a specially designed skin-stretching device, we discover that hair stem cells proliferate in response to stretch and hair regeneration occurs only when applying proper strain for an appropriate duration. A counterbalance between WNT and BMP-2 and the subsequent two-step mechanism are identified through molecular and genetic analyses. Macrophages are first recruited by chemokines produced by stretch and polarized to M2 phenotype. Growth factors such as HGF and IGF-1, released by M2 macrophages, then activate stem cells and facilitate hair regeneration. A hierarchical control system is revealed, from mechanical and chemical signals to cell behaviors and tissue responses, elucidating avenues of regenerative medicine and disease control by demonstrating the potential to manipulate cellular processes through simple mechanical stimulation.
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Affiliation(s)
- Szu-Ying Chu
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, 112, Taiwan
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, 112, Taiwan
- Department of Dermatology, National Yang-Ming University, Taipei, 112, Taiwan
| | - Chih-Hung Chou
- Department of Biological Science and Technology, Center for Intelligent Drug Systems and Smart Bio-devices (IDS2B), National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Hsien-Da Huang
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Sciences and Engineering, The Chinese University of Hong Kong, Shenzhen, 518172, China
| | - Meng-Hua Yen
- Department of Electronic Engineering, National Chin-Yi University of Technology, Taichung, 411, Taiwan
| | - Hsiao-Chin Hong
- Department of Biological Science and Technology, Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Po-Han Chao
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, 112, Taiwan
| | - Yu-Hsuan Wang
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, 999077, China
- Institute for Tissue Engineering and Regenerative Medicine, The Chinese University of Hong Kong, Hong Kong, 999077, China
| | - Po-Yu Chen
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, 112, Taiwan
- Department of Dermatology, National Yang-Ming University, Taipei, 112, Taiwan
| | - Shi-Xin Nian
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, 112, Taiwan
- Department of Dermatology, National Yang-Ming University, Taipei, 112, Taiwan
| | - Yu-Ru Chen
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, 112, Taiwan
| | - Li-Ying Liou
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, 112, Taiwan
- Department of Dermatology, National Yang-Ming University, Taipei, 112, Taiwan
| | - Yu-Chen Liu
- Department of Biological Science and Technology, Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Hui-Mei Chen
- Department of Biological Science and Technology, Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Feng-Mao Lin
- Department of Biological Science and Technology, Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, 300, Taiwan
| | - Yun-Ting Chang
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, 112, Taiwan
- Department of Dermatology, National Yang-Ming University, Taipei, 112, Taiwan
| | - Chih-Chiang Chen
- Department of Dermatology, Taipei Veterans General Hospital, Taipei, 112, Taiwan.
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, 112, Taiwan.
- Department of Dermatology, National Yang-Ming University, Taipei, 112, Taiwan.
| | - Oscar K Lee
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, 112, Taiwan.
- Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong, 999077, China.
- Institute for Tissue Engineering and Regenerative Medicine, The Chinese University of Hong Kong, Hong Kong, 999077, China.
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17
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Kosykh A, Beilin A, Sukhinich K, Vorotelyak E. Postnatal neural crest stem cells from hair follicle interact with nerve tissue in vitro and in vivo. Tissue Cell 2018; 54:94-104. [PMID: 30309515 DOI: 10.1016/j.tice.2018.08.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 08/16/2018] [Accepted: 08/17/2018] [Indexed: 01/05/2023]
Abstract
Neural crest stem cells that located in the postnatal hair follicle (HF-NCSC) are considered a promising tool for treatment of nervous system diseases and injuries. It is well known that HF-NCSC can be used in the spinal cord and sciatic nerve reparation but their ability to restore brain structures is poorly studied. In this article we are investigating the interaction between HF-NCSC and a nerve tissue (embryonic and adult). We have found out that HF-NCSC isolated from adult mice grow and differentiate in accordance with the mouse embryo developmental stage when co-cultured with the embryonic nerve tissue. The HF-NCSC migration is slower in the late embryonic tissue co-culture system compared to the early one. This phenomenon is related to the motor function of the cells but not to their proliferation level. We have demonstrated that the embryonic nerve tissue maintains HF-NCSC an undifferentiated status, while an adult brain tissue inhibits the cell proliferation and activates the differentiation processes. Besides, HF-NCSC pre-differentiated into the neuronal direction shows a higher survival and migration rate after the transplantation into the adult brain tissue compared to the undifferentiated HF-NCSC. Thus, we have investigated the postnatal HF-NCSC response to the nerve tissue microenvironment to analyze their possible application to the brain repair processes.
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Affiliation(s)
- Anastasiia Kosykh
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Vavilova 26, 119334, Moscow, Russian Federation; Pirogov Russian National Research Medical University, Ostrovitianova 1, 117997, Moscow, Russian Federation.
| | - Arkadii Beilin
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Vavilova 26, 119334, Moscow, Russian Federation
| | - Kirill Sukhinich
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Vavilova 26, 119334, Moscow, Russian Federation
| | - Ekaterina Vorotelyak
- Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Vavilova 26, 119334, Moscow, Russian Federation; Pirogov Russian National Research Medical University, Ostrovitianova 1, 117997, Moscow, Russian Federation; Lomonosov Moscow State University, Leninskie Gory 1, Moscow, Russian Federation
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18
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Pantelireis N, Higgins CA. A bald statement - Current approaches to manipulate miniaturisation focus only on promoting hair growth. Exp Dermatol 2018; 27:959-965. [PMID: 29787625 DOI: 10.1111/exd.13690] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/15/2018] [Indexed: 12/17/2022]
Abstract
Hair plays a large part in communication and society with its role changing through time and across cultures. Most people do not leave the house before combing their hair or shaving their beard and for many hair loss or irregular hair growth can have a significant impact on their psychological health. Somewhat unsurprisingly, according to GMR Data, today's global hair care industry is worth an estimated $87 Billion, with hair loss estimated at $2.8 Billion. Considering that no current hair loss-related products can completely reverse hair loss, it is reasonable to believe this market could expand significantly with the discovery of a comprehensive therapy. As such, a great deal of research focuses on overcoming hair loss, and in particular, a common form of hair loss known as androgenetic alopecia (AGA) or male pattern baldness. In AGA, hair follicles miniaturise in a large step change from a terminal to a vellus state. Within this viewpoint article, we discuss how influx and efflux of cells into and out from the dermal papilla (DP) can modulate DP size during the hair cycle. As DP size is positively correlated with the size of the hair fibre produced by a follicle, we argue here that therapies for treating AGA should be developed which can alter DP size, rather than just promote hair growth. We also discuss current therapeutics for AGA and emphasise the importance of using the right model systems to analyse miniaturisation.
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Affiliation(s)
| | - Claire A Higgins
- Department of Bioengineering, Imperial College London, London, UK
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19
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Kiani MT, Higgins CA, Almquist BD. The Hair Follicle: An Underutilized Source of Cells and Materials for Regenerative Medicine. ACS Biomater Sci Eng 2018; 4:1193-1207. [PMID: 29682604 PMCID: PMC5905671 DOI: 10.1021/acsbiomaterials.7b00072] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The hair follicle is one of only two structures within the adult body that selectively degenerates and regenerates, making it an intriguing organ to study and use for regenerative medicine. Hair follicles have been shown to influence wound healing, angiogenesis, neurogenesis, and harbor distinct populations of stem cells; this has led to cells from the follicle being used in clinical trials for tendinosis and chronic ulcers. In addition, keratin produced by the follicle in the form of a hair fiber provides an abundant source of biomaterials for regenerative medicine. In this review, we provide an overview of the structure of a hair follicle, explain the role of the follicle in regulating the microenvironment of skin and the impact on wound healing, explore individual cell types of interest for regenerative medicine, and cover several applications of keratin-based biomaterials.
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Affiliation(s)
- Mehrdad T Kiani
- Department of Bioengineering, Royal School of Mines, Imperial College London, London SW7 2AZ UK
- Department of Materials Science, 496 Lomita Mall, Stanford University, Stanford CA 94305 USA
| | - Claire A Higgins
- Department of Bioengineering, Royal School of Mines, Imperial College London, London SW7 2AZ UK
| | - Benjamin D Almquist
- Department of Bioengineering, Royal School of Mines, Imperial College London, London SW7 2AZ UK
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20
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Harland DP. Environment of the Anagen Follicle. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1054:97-108. [DOI: 10.1007/978-981-10-8195-8_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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21
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Rojas-Martínez A, Martinez-Jacobo L, Villarreal-Villarreal C, Ortiz-López R, Ocampo-Candiani J. Genetic and molecular aspects of androgenetic alopecia. Indian J Dermatol Venereol Leprol 2018; 84:263-268. [DOI: 10.4103/ijdvl.ijdvl_262_17] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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22
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English RS. A hypothetical pathogenesis model for androgenic alopecia: clarifying the dihydrotestosterone paradox and rate-limiting recovery factors. Med Hypotheses 2017; 111:73-81. [PMID: 29407002 DOI: 10.1016/j.mehy.2017.12.027] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 11/25/2017] [Accepted: 12/28/2017] [Indexed: 12/30/2022]
Abstract
Androgenic alopecia, also known as pattern hair loss, is a chronic progressive condition that affects 80% of men and 50% of women throughout a lifetime. But despite its prevalence and extensive study, a coherent pathology model describing androgenic alopecia's precursors, biological step-processes, and physiological responses does not yet exist. While consensus is that androgenic alopecia is genetic and androgen-mediated by dihydrotestosterone, questions remain regarding dihydrotestosterone's exact role in androgenic alopecia onset. What causes dihydrotestosterone to increase in androgenic alopecia-prone tissues? By which mechanisms does dihydrotestosterone miniaturize androgenic alopecia-prone hair follicles? Why is dihydrotestosterone also associated with hair growth in secondary body and facial hair? Why does castration (which decreases androgen production by 95%) stop pattern hair loss, but not fully reverse it? Is there a relationship between dihydrotestosterone and tissue remodeling observed alongside androgenic alopecia onset? We review evidence supporting and challenging dihydrotestosterone's causal relationship with androgenic alopecia, then propose an evidence-based pathogenesis model that attempts to answer the above questions, account for additionally-suspected androgenic alopecia mediators, identify rate-limiting recovery factors, and elucidate better treatment targets. The hypothesis argues that: (1) chronic scalp tension transmitted from the galea aponeurotica induces an inflammatory response in androgenic alopecia-prone tissues; (2) dihydrotestosterone increases in androgenic alopecia-prone tissues as part of this inflammatory response; and (3) dihydrotestosterone does not directly miniaturize hair follicles. Rather, dihydrotestosterone is a co-mediator of tissue dermal sheath thickening, perifollicular fibrosis, and calcification - three chronic, progressive conditions concomitant with androgenic alopecia progression. These conditions remodel androgenic alopecia-prone tissues - restricting follicle growth space, oxygen, and nutrient supply - leading to the slow, persistent hair follicle miniaturization characterized in androgenic alopecia. If true, this hypothetical model explains the mechanisms by which dihydrotestosterone miniaturizes androgenic alopecia-prone hair follicles, describes a rationale for androgenic alopecia progression and patterning, makes sense of dihydrotestosterone's paradoxical role in hair loss and hair growth, and identifies targets to further improve androgenic alopecia recovery rates: fibrosis, calcification, and chronic scalp tension.
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23
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Sinclair RD. Female pattern hair loss: a pilot study investigating combination therapy with low-dose oral minoxidil and spironolactone. Int J Dermatol 2017; 57:104-109. [PMID: 29231239 DOI: 10.1111/ijd.13838] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 09/08/2017] [Accepted: 10/18/2017] [Indexed: 01/26/2023]
Abstract
BACKGROUND Minoxidil and spironolactone are oral antihypertensives known to stimulate hair growth. OBJECTIVE To report on a case series of women with pattern hair loss (PHL) treated with once daily minoxidil 0.25 mg and spironolactone 25 mg. METHODS Women newly diagnosed with a Sinclair stage 2-5 PHL were scored for hair shedding and hair density before and after 12 months of treatment with oral minoxidil 0.25 mg and spironolactone 25 mg. RESULTS A total of 100 women were included in this observational pilot study. Mean age was 48.44 years (range 18-80). Mean hair loss severity at baseline was Sinclair 2.79 (range 2-5). Mean hair shedding score at baseline was 4.82. Mean duration of diagnosis was 6.5 years (range 0.5-30). Mean reduction in hair loss severity score was 0.85 at 6 months and 1.3 at 12 months. Mean reduction in hair shedding score was 2.3 at 6 months and 2.6 at 12 months. Mean change in blood pressure was -4.52 mmHg systolic and -6.48 mmHg diastolic. Side effects were seen in eight women but were generally mild. No patients developed hyperkalemia or any other blood test abnormality. Six of these women continued treatment, and two women who developed urticaria discontinued treatment. LIMITATIONS Prospective, uncontrolled, open-label observational study. DISCUSSION Once daily capsules containing minoxidil 0.25 mg and spironolactone 25 mg appear to be safe and effective in the treatment of FPHL. Placebo-controlled studies to investigate this further are warranted.
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Affiliation(s)
- Rodney D Sinclair
- Epworth Hospital, East Melbourne, Vic., Australia.,Sinclair Dermatology Clinical Trial Centre, East Melbourne, Vic., Australia
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24
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Garg S, Manchanda S. Platelet-rich plasma-an 'Elixir' for treatment of alopecia: personal experience on 117 patients with review of literature. Stem Cell Investig 2017; 4:64. [PMID: 28815175 DOI: 10.21037/sci.2017.06.07] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 05/26/2017] [Indexed: 11/06/2022]
Abstract
Platelet-rich plasma (PRP) has emerged as a new treatment modality in regenerative plastic surgery and dermatology. PRP is a simple, cost-effective and feasible treatment option with high patient satisfaction for hair loss and can be regarded as a valuable adjuvant treatment modality for androgenic alopecia and other types of non-scarring alopecias. Authors have proposed a hair model termed "Golden anchorage with 'molecular locking' of ectodermal and mesenchymal components for survival and integrity of hair follicle (HF)" in this article. Golden anchorage comprises of bulge stem cells, ectodermal basement membrane and bulge portion of APM. PRP with its autologous supply of millions of growth factors works on 'Golden anchorage' along with keratinocytes (PDGF), dermal papilla (IGF and fibroblast growth factor), vasculature (VEGF and PDGF) and neural cells (Nerve Growth Factor) in a multipronged manner serving as an 'elixir' for hair growth and improving overall environment.
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Affiliation(s)
- Suruchi Garg
- Department of Dermatology and Aesthetic Surgery, Aura Skin Institute, Chandigarh, India
| | - Shweta Manchanda
- Department of Dermatology and Aesthetic Surgery, Aura Skin Institute, Chandigarh, India
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25
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Redler S, Messenger AG, Betz RC. Genetics and other factors in the aetiology of female pattern hair loss. Exp Dermatol 2017; 26:510-517. [DOI: 10.1111/exd.13373] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/24/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Silke Redler
- Institute of Human Genetics; University Clinic Düsseldorf; Heinrich-Heine-University; Düsseldorf Germany
| | | | - Regina C. Betz
- Institute of Human Genetics; University of Bonn; Bonn Germany
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26
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Ji J, Ho BSY, Qian G, Xie XM, Bigliardi PL, Bigliardi-Qi M. Aging in hair follicle stem cells and niche microenvironment. J Dermatol 2017; 44:1097-1104. [PMID: 28593683 DOI: 10.1111/1346-8138.13897] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/23/2017] [Indexed: 01/25/2023]
Abstract
Hair graying and hair loss are prominent and common characteristics of the elderly population. In some individuals these processes can significantly impact their quality of life, leading to depression, anxiety and other serious mental health problems. Accordingly, there has been much interest in understanding the complex physiological changes within the hair follicle in the aging individual. It is now known that hair follicles represent a prototypical stem cell niche, where both micro- and macroenvironmental influences are integrated alongside stem cell-stem cell and stem cell-stem niche interactions to determine hair growth or hair follicle senescence. Recent studies have identified imbalanced stem cell differentiation and altered stem cell activity as important factors during hair loss, indicating new avenues for the development of therapeutic agents to stimulate hair growth. Here, we pull together the latest findings on the hair follicle stem cell niche and the multifactorial interactions underlying the various forms of hair loss.
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Affiliation(s)
- Jiang Ji
- Department of Dermatology, The Second Affiliated Hospital of Soochow University, Su Zhou, China
| | - Bryan Siu-Yin Ho
- Institute of Medical Biology, Agency for Science, Technology and Research, Singapore
| | - Ge Qian
- Department of Dermatology, Zhengzhou Children's Hospital, Zhengzhou, China
| | - Xiao-Ming Xie
- Department of Dermatology, The Second Affiliated Hospital of Soochow University, Su Zhou, China
| | - Paul Lorenz Bigliardi
- Institute of Medical Biology, Agency for Science, Technology and Research, Singapore
| | - Mei Bigliardi-Qi
- Institute of Medical Biology, Agency for Science, Technology and Research, Singapore
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27
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The arrector pili muscle, the bridge between the follicular stem cell niche and the interfollicular epidermis. Anat Sci Int 2016; 92:151-158. [PMID: 27473595 DOI: 10.1007/s12565-016-0359-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 07/16/2016] [Indexed: 10/21/2022]
Abstract
Proximally, the arrector pili muscle (APM) attaches to the follicular stem cell niche in the bulge, but its distal properties are comparatively unclear. In this work, a novel method employing an F-actin probe, phalloidin, was employed to visualize the APM anatomy. Phalloidin staining of the APM was validated by comparison with conventional antibodies/stains and by generating three-dimensional reconstructions. The proximal attachment of the APM to the bulge in 8 patients with androgenic alopecia was studied using Masson's trichrome stain. Phalloidin visualized extensive branching of the APM. The distal end of the human APM exhibits a unique "C"-shaped structure connecting to the dermal-epidermal junction. The proximal APM attachment was observed to be lost or extremely miniaturized in androgenic alopecia. The unique shape, location, and attachment sites of the APM suggest a significant role for this muscle in maintaining follicular integrity. Proximally, the APM encircles the follicular unit and only attaches to the primary hair follicle in the bulge; this attachment is lost in irreversible hair loss. The APM exhibits an arborized morphology as it ascends toward the epidermis, and anchors to the basement membrane.
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28
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Epidermal Cells Expressing Putative Cell Markers in Nonglabrous Skin Existing in Direct Proximity with the Distal End of the Arrector Pili Muscle. Stem Cells Int 2016; 2016:1286315. [PMID: 27375744 PMCID: PMC4916308 DOI: 10.1155/2016/1286315] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 05/17/2016] [Indexed: 11/17/2022] Open
Abstract
Inconsistent with the view that epidermal stem cells reside randomly spread along the basal layer of the epidermal rete ridges, we found that epidermal cells expressing stem cell markers in nonglabrous skin exist in direct connection with the distal end of the arrector pili muscle. The epidermal cells that express stem cell markers consist of a subpopulation of basal keratinocytes located in a niche at the lowermost portion of the rete ridges at the distal arrector pili muscle attachment site. Keratinocytes in the epidermal stem cell niche express K15, MCSP, and α6 integrin. α5 integrin marks the distal end of the APM colocalized with basal keratinocytes expressing stem cell markers located in a well-protected and nourished environment at the lowermost point of the epidermis; these cells are hypothesized to participate directly in epidermal renewal and homeostasis and also indirectly in wound healing through communication with the hair follicle bulge epithelial stem cell population through the APM. Our findings, plus a reevaluation of the literature, support the hierarchical model of interfollicular epidermal stem cell units of Fitzpatrick. This new view provides insights into epidermal control and the possible involvement of epidermal stem cells in nonmelanoma skin carcinogenesis.
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29
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Sinclair R. Androgenetic alopecia. Modelling progression and regrowth. Exp Dermatol 2016; 25:424-5. [DOI: 10.1111/exd.13029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2016] [Indexed: 11/27/2022]
Affiliation(s)
- Rodney Sinclair
- Department of Dermatology; University of Melbourne; Epworth Hospital; Melbourne Vic. Australia
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30
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Sinclair R, Torkamani N, Jones L. Androgenetic alopecia: new insights into the pathogenesis and mechanism of hair loss. F1000Res 2015; 4:585. [PMID: 26339482 PMCID: PMC4544386 DOI: 10.12688/f1000research.6401.1] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/18/2015] [Indexed: 12/21/2022] Open
Abstract
The hair follicle is a complete mini-organ that lends itself as a model for investigation of a variety of complex biological phenomena, including stem cell biology, organ regeneration and cloning. The arrector pili muscle inserts into the hair follicle at the level of the bulge- the epithelial stem cell niche. The arrector pili muscle has been previously thought to be merely a bystander and not to have an active role in hair disease. Computer generated 3D reconstructions of the arrector pili muscle have helped explain why women with androgenetic alopecia (AGA) experience diffuse hair loss rather than the patterned baldness seen in men. Loss of attachment between the bulge stem cell population and the arrector pili muscle also explains why miniaturization is irreversible in AGA but not alopecia areata. A new model for the progression of AGA is presented.
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Affiliation(s)
- Rodney Sinclair
- Department of Medicine, University of Melbourne, Victoria, Australia ; Epworth Dermatology, Victoria, Australia ; Sinclair Dermatology, Victoria, Australia
| | - Niloufar Torkamani
- Department of Medicine, University of Melbourne, Victoria, Australia ; Epworth Dermatology, Victoria, Australia ; Sinclair Dermatology, Victoria, Australia
| | - Leslie Jones
- Department of Medicine, University of Melbourne, Victoria, Australia ; Epworth Dermatology, Victoria, Australia ; Sinclair Dermatology, Victoria, Australia
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Torkamani N, Rufaut NW, Jones L, Sinclair RD. Beyond goosebumps: does the arrector pili muscle have a role in hair loss? Int J Trichology 2014; 6:88-94. [PMID: 25210331 PMCID: PMC4158628 DOI: 10.4103/0974-7753.139077] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The arrector pili muscle (APM) consists of a small band of smooth muscle that connects the hair follicle to the connective tissue of the basement membrane. The APM mediates thermoregulation by contracting to increase air-trapping, but was thought to be vestigial in humans. The APM attaches proximally to the hair follicle at the bulge, a known stem cell niche. Recent studies have been directed toward this muscle's possible role in maintaining the follicular integrity and stability. This review summarizes APM anatomy and physiology and then discusses the relationship between the follicular unit and the APM. The potential role of the APM in hair loss disorders is also described, and a model explaining APM changes in hair loss is proposed.
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Affiliation(s)
- Niloufar Torkamani
- University of Melbourne, Melbourne, Victoria, Australia ; Epworth Hospital, Melbourne, Victoria, Australia
| | - Nicholas W Rufaut
- University of Melbourne, Melbourne, Victoria, Australia ; Epworth Hospital, Melbourne, Victoria, Australia
| | - Leslie Jones
- University of Melbourne, Melbourne, Victoria, Australia ; Epworth Hospital, Melbourne, Victoria, Australia
| | - Rodney D Sinclair
- University of Melbourne, Melbourne, Victoria, Australia ; Epworth Hospital, Melbourne, Victoria, Australia
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