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Ma J, Qin C, Wu J, Zhuang H, Du L, Xu J, Wu C. 3D multicellular micropatterning biomaterials for hair regeneration and vascularization. MATERIALS HORIZONS 2023; 10:3773-3784. [PMID: 37409407 DOI: 10.1039/d3mh00528c] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
Hair loss caused by the abnormal functions of hair follicles in skin can seriously impact the quality of an individual's life. The development of sophisticated skin tissue-engineered constructs is required to enable the function recovery of hair follicles. However, effective hair regrowth in skin substitutes still remains a great challenge. In this study, a 3D multicellular micropattern was successfully fabricated by arranging the hair follicle-related cells orderly distributed in the interval of vascular-cell networks via bioprinting technology. By combining the stable biomimetic micropattern structure and the bio-inducing substrate incorporated with magnesium silicate (MS) nanomaterials, the 3D multicellular micropattern possessed significant follicular potential and angiogenic capacity in vitro. Furthermore, the 3D multicellular micropattern with MS incorporation contributed to efficient hair regrowth during skin tissue regeneration in both immunodeficient mice and androgenetic alopecia (AGA) mice models. Thus, this study proposes a novel 3D micropatterned multicellular system assembling a biomimetic micro-structure and modulating the cell-cell interaction for hair regeneration during skin reconstruction.
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Affiliation(s)
- Jingge Ma
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China.
- Institute of Respiratory Medicine, Tongji University School of Medicine, Shanghai 200433, P. R. China
| | - Chen Qin
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jinfu Wu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hui Zhuang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Lin Du
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jinfu Xu
- Institute of Respiratory Medicine, Tongji University School of Medicine, Shanghai 200433, P. R. China
| | - Chengtie Wu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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2
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Choi HI, Kang BM, Jang J, Hwang ST, Kwon O. Novel effect of sildenafil on hair growth. Biochem Biophys Res Commun 2018; 505:685-691. [PMID: 30292404 DOI: 10.1016/j.bbrc.2018.09.164] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 09/25/2018] [Indexed: 11/25/2022]
Abstract
BACKGROUND Sildenafil, a phosphodiesterase 5 (PDE5) inhibitor, is known to increase the intracellular level of cyclic guanosine monophosphate (cGMP), which causes vasodilation. However, the effect of sildenafil on human hair follicles (hHFs) is unknown. OBJECTIVE The purpose of this study was to determine the role of sildenafil in hair growth. METHODS We investigated the expression of PDE5 in human dermal papilla cells (hDPCs) and hHFs. The effects of sildenafil on hDPC proliferation were evaluated using BrdU assays. The mRNA expression of growth factors and extracellular signal-regulated kinase (ERK) phosphorylation were investigated using real-time PCR and western blotting, respectively. Additionally, anagen induction and perifollicular vessel formation were evaluated using an in vivo mice model. RESULTS We confirmed high expression of PDE5 in hDPCs and hHFs. Sildenafil enhances proliferation of hDPCs and up-regulates the mRNA expression of vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), which are responsible for hair growth. Additionally, sildenafil up-regulates the levels of phosphorylated ERK and accelerates anagen induction by stimulating perifollicular vessel formation after topical application in mice. CONCLUSION Our study demonstrates for the first time, the significant therapeutic potential of sildenafil on hair growth and its potential use in treatment of alopecia.
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Affiliation(s)
- Hye-In Choi
- Laboratory of Cutaneous Aging and Hair Research, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Institute of Human Environment Interface Biology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Bo-Mi Kang
- Laboratory of Cutaneous Aging and Hair Research, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Institute of Human Environment Interface Biology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jeehee Jang
- Laboratory of Cutaneous Aging and Hair Research, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Institute of Human Environment Interface Biology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | | | - Ohsang Kwon
- Laboratory of Cutaneous Aging and Hair Research, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea; Institute of Human Environment Interface Biology, Seoul National University College of Medicine, Seoul, Republic of Korea; Department of Dermatology, Seoul National University College of Medicine, Seoul, Republic of Korea.
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3
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Kim B, Jang C, Dharaneeswaran H, Li J, Bhide M, Yang S, Li K, Arany Z. Endothelial pyruvate kinase M2 maintains vascular integrity. J Clin Invest 2018; 128:4543-4556. [PMID: 30222136 PMCID: PMC6159968 DOI: 10.1172/jci120912] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 07/26/2018] [Indexed: 12/25/2022] Open
Abstract
The M2 isoform of pyruvate kinase (PKM2) is highly expressed in most cancer cells, and has been studied extensively as a driver of oncogenic metabolism. In contrast, the role of PKM2 in nontransformed cells is little studied, and nearly nothing is known of its role, if any, in quiescent cells. We show here that endothelial cells express PKM2 almost exclusively over PKM1. In proliferating endothelial cells, PKM2 is required to suppress p53 and maintain cell cycle progression. In sharp contrast, PKM2 has a strikingly different role in quiescent endothelial cells, where inhibition of PKM2 leads to degeneration of tight junctions and barrier function. Mechanistically, PKM2 regulates barrier function independently of its canonical activity as a pyruvate kinase. Instead, PKM2 suppresses NF-kB and its downstream target, the vascular permeability factor angiopoietin 2. As a consequence, loss of endothelial cell PKM2 in vivo predisposes mice to VEGF-induced vascular leak, and to severe bacteremia and death in response to sepsis. Together, these data demonstrate new roles of PKM2 in quiescent cells, and highlight the need for caution in developing cancer therapies that target PKM2.
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Affiliation(s)
- Boa Kim
- Cardiovascular Institute and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Cholsoon Jang
- Department of Chemistry and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA
| | - Harita Dharaneeswaran
- Cardiovascular Institute and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jian Li
- Cardiovascular Institute and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Mohit Bhide
- Cardiovascular Institute and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Steven Yang
- Cardiovascular Institute and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kristina Li
- Cardiovascular Institute and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Zolt Arany
- Cardiovascular Institute and Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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4
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Yu M, Finner A, Shapiro J, Lo B, Barekatain A, McElwee KJ. Hair follicles and their role in skin health. ACTA ACUST UNITED AC 2014. [DOI: 10.1586/17469872.1.6.855] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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5
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Abstract
The hair follicle, a unique characteristic of mammals, represents a stem cell-rich, prototypic neuroectodermal-mesodermal interaction system. This factory for pigmented epithelial fibers is unique in that it is the only organ in the mammalian body which, for its entire lifetime, undergoes cyclic transformations from stages of rapid growth (anagen) to apoptosis-driven regression (catagen) and back to anagen, via an interspersed period of relative quiescence (telogen). While it is undisputed that the biological "clock" that drives hair follicle cycling resides in the hair follicle itself, the molecular nature of the underlying oscillator system remains to be clarified. To meet this challenge is of profound general interest, since numerous key problems of modern biology can be studied exemplarily in this versatile model system. It is also clinically important, since the vast majority of patients with hair growth disorders suffers from an undesired alteration of hair follicle cycling. Here, we sketch basic background information and key concepts that one needs to keep in mind when exploring the enigmatic "hair cycle clock"(HCC), and summarize competing models of the HCC. We invite the reader on a very subjective guided tour, which focuses on our own trials, errors, and findings toward the distant goal of unravelling one of the most fascinating mysteries of biology: Why does the hair follicle cycle at all? How does it do it? What are the key players in the underlying molecular controls? Attempting to offer at least some meaningful answers, we share our prejudices and perspectives, and define crucial open questions.
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Affiliation(s)
- Ralf Paus
- Department of Dermatology, University Hospital Hamburg-Eppendorf, University of Hamburg, Martinistr. 52, D-20426 Hamburg, Germany.
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6
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Yano K, Brown LF, Detmar M. Control of hair growth and follicle size by VEGF-mediated angiogenesis. J Clin Invest 2001; 107:409-17. [PMID: 11181640 PMCID: PMC199257 DOI: 10.1172/jci11317] [Citation(s) in RCA: 434] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The murine hair follicle undergoes pronounced cyclic expansion and regression, leading to rapidly changing demands for its vascular support. Our study aimed to quantify the cyclic changes of perifollicular vascularization and to characterize the biological role of VEGF for hair growth, angiogenesis, and follicle cycling. We found a significant increase in perifollicular vascularization during the growth phase (anagen) of the hair cycle, followed by regression of angiogenic blood vessels during the involution (catagen) and the resting (telogen) phase. Perifollicular angiogenesis was temporally and spatially correlated with upregulation of VEGF mRNA expression by follicular keratinocytes of the outer root sheath, but not by dermal papilla cells. Transgenic overexpression of VEGF in outer root sheath keratinocytes of hair follicles strongly induced perifollicular vascularization, resulting in accelerated hair regrowth after depilation and in increased size of hair follicles and hair shafts. Conversely, systemic treatment with a neutralizing anti-VEGF antibody led to hair growth retardation and reduced hair follicle size. No effects of VEGF treatment or VEGF blockade were observed in mouse vibrissa organ cultures, which lack a functional vascular system. These results identify VEGF as a major mediator of hair follicle growth and cycling and provide the first direct evidence that improved follicle vascularization promotes hair growth and increases hair follicle and hair size.
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Affiliation(s)
- K Yano
- Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital, Building 149, 13th Street, Charlestown, MA 02129, USA
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7
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Vasile E, Tomita Y, Brown LF, Kocher O, Dvorak HF. Differential expression of thymosin beta-10 by early passage and senescent vascular endothelium is modulated by VPF/VEGF: evidence for senescent endothelial cells in vivo at sites of atherosclerosis. FASEB J 2001; 15:458-66. [PMID: 11156961 DOI: 10.1096/fj.00-0051com] [Citation(s) in RCA: 178] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
VPF/VEGF acts selectively on the vascular endothelium to enhance permeability, induce cell migration and division, and delay replicative senescence. To understand the changes in gene expression during endothelial senescence, we investigated genes that were differentially expressed in early vs. late passage (senescent) human dermal endothelial cells (HDMEC) using cDNA array hybridization. Early passage HDMEC cultured with or without VPF/VEGF overexpressed 9 and underexpressed 6 genes in comparison with their senescent counterparts. Thymosin beta-10 expression was modulated by VPF/VEGF and was strikingly down-regulated in senescent EC. The beta-thymosins are actin G-sequestering peptides that regulate actin dynamics and are overexpressed in neoplastic transformation. We have also identified senescent EC in the human aorta at sites overlying atherosclerotic plaques. These EC expressed senescence-associated neutral beta-galactosidase and, in contrast to adventitial microvessel endothelium, exhibited weak staining for thymosin beta-10. ISH performed on human malignant tumors revealed strong thymosin beta-10 expression in tumor blood vessels. This is the first report that Tbeta-10 expression is significantly reduced in senescent EC, that VPF/VEGF modulates thymosin beta-10 expression, and that EC can become senescent in vivo. The reduced expression of thymosin beta-10 may contribute to the senescent phenotype by reducing EC plasticity and thus impairing their response to migratory stimuli.
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MESH Headings
- Actins/genetics
- Adenocarcinoma/pathology
- Aorta, Thoracic/pathology
- Arteriosclerosis/pathology
- Arteriosclerosis/physiopathology
- Cells, Cultured
- Cellular Senescence/drug effects
- Cellular Senescence/physiology
- Colonic Neoplasms/blood supply
- DNA, Complementary
- Endothelial Growth Factors/pharmacology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/pathology
- Endothelium, Vascular/physiology
- Gene Expression Regulation
- Humans
- Infant, Newborn
- Lymphokines/pharmacology
- Male
- Microcirculation/pathology
- RNA, Messenger/genetics
- Skin/blood supply
- Thymosin/genetics
- Transcription, Genetic
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
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Affiliation(s)
- E Vasile
- Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA.
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8
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Abstract
Nearly 50 years ago, Chase published a review of hair cycling in which he detailed hair growth in the mouse and integrated hair biology with the biology of his day. In this review we have used Chase as our model and tried to put the adult hair follicle growth cycle in perspective. We have tried to sketch the adult hair follicle cycle, as we know it today and what needs to be known. Above all, we hope that this work will serve as an introduction to basic biologists who are looking for a defined biological system that illustrates many of the challenges of modern biology: cell differentiation, epithelial-mesenchymal interactions, stem cell biology, pattern formation, apoptosis, cell and organ growth cycles, and pigmentation. The most important theme in studying the cycling hair follicle is that the follicle is a regenerating system. By traversing the phases of the cycle (growth, regression, resting, shedding, then growth again), the follicle demonstrates the unusual ability to completely regenerate itself. The basis for this regeneration rests in the unique follicular epithelial and mesenchymal components and their interactions. Recently, some of the molecular signals making up these interactions have been defined. They involve gene families also found in other regenerating systems such as fibroblast growth factor, transforming growth factor-beta, Wnt pathway, Sonic hedgehog, neurotrophins, and homeobox. For the immediate future, our challenge is to define the molecular basis for hair follicle growth control, to regenerate a mature hair follicle in vitro from defined populations, and to offer real solutions to our patients' problems.
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Affiliation(s)
- K S Stenn
- Beauty Genome Sciences Inc., Skillman, New Jersey, USA.
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9
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Mecklenburg L, Tobin DJ, Müller-Röver S, Handjiski B, Wendt G, Peters EM, Pohl S, Moll I, Paus R. Active hair growth (anagen) is associated with angiogenesis. J Invest Dermatol 2000; 114:909-16. [PMID: 10771470 DOI: 10.1046/j.1523-1747.2000.00954.x] [Citation(s) in RCA: 179] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
After the completion of skin development, angiogenesis, i.e., the growth of new capillaries from pre-existing blood vessels, is held to occur in the skin only under pathologic conditions. It has long been noted, however, that hair follicle cycling is associated with prominent changes in skin perfusion, that the epithelial hair bulbs of anagen follicles display angiogenic properties, and that the follicular dermal papilla can produce angiogenic factors. Despite these suggestive observations, no formal proof is as yet available for the concept that angiogenesis is a physiologic event that occurs all over the mature mammalian integument whenever hair follicles switch from resting (telogen) to active growth (anagen). This study uses quantitative histomorphometry and double-immunohistologic detection techniques for the demarcation of proliferating endothelial cells, to show that synchronized hair follicle cycling in adolescent C57BL/6 mice is associated with substantial angiogenesis, and that inhibiting angiogenesis in vivo by the intraperitoneal application of a fumagillin derivative retards experimentally induced anagen development in these mice. Thus, angiogenesis is a physiologic event in normal postnatal murine skin, apparently is dictated by the hair follicle, and appears to be required for normal anagen development. Anagen-associated angiogenesis offers an attractive model for identifying the physiologic controls of cutaneous angiogenesis, and an interesting system for screening the effects of potential antiangiogenic drugs in vivo.
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Affiliation(s)
- L Mecklenburg
- Department of Dermatology, University Hospital Eppendorf, University of Hamburg, Germany
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10
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Yang J, Chang E, Cherry AM, Bangs CD, Oei Y, Bodnar A, Bronstein A, Chiu CP, Herron GS. Human endothelial cell life extension by telomerase expression. J Biol Chem 1999; 274:26141-8. [PMID: 10473565 DOI: 10.1074/jbc.274.37.26141] [Citation(s) in RCA: 339] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Normal human endothelial cells, like other somatic cells in culture, divide a limited number of times before entering a nondividing state called replicative senescence. Expression of the catalytic component of human telomerase, human telomerase reverse transcriptase (hTERT), extends the life span of human fibroblasts and retinal pigment epithelial cells beyond senescence without causing neoplastic transformation (Bodnar, A. G., Ouellette, M., Frolkis, M., Holt, S. E., Chiu, C. P., Morin, G. B., Harley, C. B., Shay, J. W., Lichtsteiner, S., and Wright, W. E. (1998) Science 279, 349-352; Jiang, X., Jimenez, G., Chang, E., Frolkis, M., Kusler, B., Sage, M., Beeche, M., Bodnar, A., Wahl, G., Tlsty, T., and Chiu, C.-P. (1999) Nat. Genet. 21, 111-114). Here, we show that both human large vessel and microvascular endothelial cells also bypass replicative senescence after introduction of hTERT. For the first time, we report that hTERT expression in these life-extended vascular cells does not affect their differentiated and functional phenotype and that these cells maintain their angiogenic potential in vitro. Furthermore, hTERT(+) microvascular endothelial cells have normal karyotype, and hTERT(+) endothelial cell strains do not exhibit a transformed phenotype. Relative to parental cells at senescence, hTERT-expressing endothelial cells exhibit resistance to induction of apoptosis by a variety of different conditions. Such characteristics are highly desirable for designing vascular transplantation and gene therapy delivery systems in vivo.
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Affiliation(s)
- J Yang
- Department of Dermatology, Stanford University School of Medicine, Stanford, California 94305-5486, USA
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11
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Bonakdar MP, Barber PM, Newman HN. The vasculature in chronic adult periodontitis: a qualitative and quantitative study. J Periodontol 1997; 68:50-8. [PMID: 9029452 DOI: 10.1902/jop.1997.68.1.50] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Blood vessel features in periodontal pocket soft tissues may be significant in the pathogenesis and progression of chronic periodontitis. The aim of this study was to make a quantitative histological assessment of the vasculature in soft tissue biopsies from patients with chronic adult periodontitis and patients with healthy periodontal tissues. We have also investigated changes in tissue morphology at both the histological and ultrastructural level. Twelve interdental biopsies were obtained, 6 from chronic adult periodontitis patients and 6 from healthy volunteers. The specimens were sliced, fixed in 3% glutaraldehyde, postfixed in 1% buffered osmium tetroxide, dehydrated, and embeded in araldite. One micron semithin sections were differentially stained with a dichromatic technique. The number of blood vessels (BV) for sub-epithelial, superficial and deep connective tissue layers were then assessed. Only in the sub-epithelial connective tissue layer was there a significant increase in the number of blood vessels (95% Confidence interval [CI]) in the chronic adult periodontitis specimens when compared to healthy specimens. The results of this study seem to indicate that a dichromatic staining technique facilitates the identification and quantification of blood vessels in epoxy resin embedded specimens at light microscope level, and that there is an increase in the number of blood vessels in the chronic adult periodontitis lesions.
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Affiliation(s)
- M P Bonakdar
- Periodontology Department, Eastman Dental Institute and Hospital for Oral Health Care Sciences, University College London, UK
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12
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Bonakdar MP, Barber PM, Newman HN. Can capillaries increase in length without any increase in the number of endothelial cells? Med Hypotheses 1996; 47:383-8. [PMID: 8951802 DOI: 10.1016/s0306-9877(96)90218-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Generally it is believed that one of the causes of vascular expansion is the increase in length of small capillaries, which in turn is attributed to an increase in the number of endothelial cells. In this report we suggest a new hypothesis for a different mechanism for the increased length of small capillaries, which excludes an increase in the number of endothelial cells. This hypothesis is based upon the possibility of a longitudinal expansion of blood vessels, and has been explained and justified through a series of mathematical examples.
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Affiliation(s)
- M P Bonakdar
- Periodontology Department, Eastman Dental Institute, London, UK
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13
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Stenn KS, Combates NJ, Eilertsen KJ, Gordon JS, Pardinas JR, Parimoo S, Prouty SM. Hair follicle growth controls. Dermatol Clin 1996; 14:543-58. [PMID: 9238315 DOI: 10.1016/s0733-8635(05)70383-1] [Citation(s) in RCA: 110] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Research in hair biology has embarked in the pursuit for molecules that control hair growth. Many molecules already have been associated with the controls of hair patterning, hair maturation, and hair cycling and differentiation. Knowing how these molecules work gives us the tools for understanding and treating patients with hair disorders.
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Affiliation(s)
- K S Stenn
- Skin Biology Research Center, Johnson & Johnson, Skillman, New Jersey, USA
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14
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Lavker RM, Miller SJ, Sun TT. Epithelial stem cells, hair follicles, and tumor formation. Recent Results Cancer Res 1993; 128:31-43. [PMID: 8356329 DOI: 10.1007/978-3-642-84881-0_3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- R M Lavker
- Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia 19014
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15
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Skoutelis A, Freinkel RK, Kaufman DS, Leibovich SJ. Angiogenic activity is defective in monocytes from patients with alopecia universalis. J Invest Dermatol 1990; 95:139-43. [PMID: 1696299 DOI: 10.1111/1523-1747.ep12477885] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Monocyte/macrophages are important components of cell-mediated immune responses in presentation of antigen, as regulators of lymphocyte function, and as sources of cytokines that modulate functions of cells other than those of the immune system. Their role in the pathogenesis of alopecia areata (AA) and universalis (AU) has not been explored. This study is an investigation of the function of peripheral blood monocytes from normal subjects and patients with AA, AU, and alopecia totalis (AT), with respect to the principal macrophage-derived angiogenic factor, tumor necrosis factor alpha (TNF alpha). Because neovascularization is a necessary component in the anagen phase of hair growth and may play a role in the pathology of these disorders, we asked whether monocyte/macrophage angiogenic activity was compromised in these alopecias. Purified preparations of monocytes were activated in culture. Conditioned media were assessed for angiogenic activity on the chick chorioallantoic membrane and for concentration of TNF alpha by enzyme-linked immunosorbent assay (ELISA). Both angiogenic and the TNF concentration were significantly diminished in conditioned media from AU monocytes when compared to those from normal subjects and patients with AA. These results show that the function of AU monocytes may be abnormal and that the abnormality may distinguish AU from AA. Defective monocyte/macrophage function could also play a pathogenic role via effects on neovascularization and/or modulation of the immune response.
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Affiliation(s)
- A Skoutelis
- Department of Dermatology, Northwestern University Medical School, Chicago, IL 60611
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16
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Cotsarelis G, Sun TT, Lavker RM. Label-retaining cells reside in the bulge area of pilosebaceous unit: implications for follicular stem cells, hair cycle, and skin carcinogenesis. Cell 1990; 61:1329-37. [PMID: 2364430 DOI: 10.1016/0092-8674(90)90696-c] [Citation(s) in RCA: 1649] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Inconsistent with the view that hair follicle stem cells reside in the matrix area of the hair bulb, we found that label-retaining cells exist exclusively in the bulge area of the mouse hair follicle. The bulge consists of a subpopulation of outer root sheath cells located in the midportion of the follicle at the arrector pili muscle attachment site. Keratinocytes in the bulge area are relatively undifferentiated ultrastructurally. They are normally slow cycling, but can be stimulated to proliferate transiently by TPA. Located in a well-protected and nourished environment, these cells mark the lower end of the "permanent" portion of the follicle. Our findings, plus a reevaluation of the literature, suggest that follicular stem cells reside in the bulge region, instead of the lower bulb. This new view provides insights into hair cycle control and the possible involvement of hair follicle stem cells in skin carcinogenesis.
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Affiliation(s)
- G Cotsarelis
- Department of Dermatology, University of Pennsylvania School of Medicine, Philadelphia 19104
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17
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Stenn KS, Fernandez LA, Tirrell SJ. The angiogenic properties of the rat vibrissa hair follicle associate with the bulb. J Invest Dermatol 1988; 90:409-11. [PMID: 2450148 DOI: 10.1111/1523-1747.ep12456517] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
As the hair follicle is one of the most rapidly growing tissues in the body, it must be nourished by a rich blood supply. Histological studies have indicated that the number of vessels about a growing follicle exceeds that about a resting follicle, so we postulated that the hair follicle might provide its own angiogenic stimulus during certain phases of its growth. Reported here are experiments testing the angiogenic properties of the growing (anagen) hair follicle. Using the rabbit corneal pocket angiogenesis assay and cycled anagen rat vibrissae hair follicles, we found that the mesenchymal dermal papilla had no angiogenic properties, but the anagen bulb was angiogenic. These findings suggest a mechanism for the cycling of hair follicles and an example of normal epithelium to mesenchyme interactions.
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Affiliation(s)
- K S Stenn
- Clinipad Research Laboratories, Guilford, Connecticut 06437
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18
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Abstract
Controversy exists whether the initiating events in psoriasis are primarily epidermal or dermal (vascular). To study this point, serial biopsies from 6 patients were taken from the periphery of individual plaques before, and at 1 to 3 day intervals during, Goeckerman and PUVA treatments. Part of the biopsy was studied by electron microscopy to determine the fine structure of the capillary loops and part was incubated with tritiated thymidine to determine the labeling index (LI) of the basal cells. Normal appearing buttock skin of the 11 other psoriatic patients not under treatment was studied by identical methods. In 4 of the 6 treated patients, the capillary loops began to return toward normal 3 to 8 days before the LI began to decrease. Two patients did not show a return toward normal of either capillaries or LI during the period of the experiment. The LI was elevated in the normal appearing buttock skin of 6 of 11 untreated psoriatics. In 4 of the 6, the loops were normal arterial capillaries. We did not observe abnormal (venous) capillaries associated with a normal LI in the other 5 untreated patients. These data support the concept that the initiating factors in psoriasis are in the epidermis, but epidermal hyperplasia cannot occur without vascular proliferation. Understanding the factors responsible for shortening the capillary loops during epidermal normalization and for inhibition of capillary growth in the presence of an increased LI could lead to other ways of controlling psoriasis.
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Moe H, Thorball N, Nielsen HW. Structural alterations in proliferating, remodeling, and regressing tooth pulp arterioles. Cell Tissue Res 1979; 203:339-54. [PMID: 519725 DOI: 10.1007/bf00233263] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In the continuously growing upper incisor of 100 g rats about 25 arterioles arise from an artery outside the tooth and pass through the apical foramen to run parallel to one another in the central part of the pulp, each supplying a well-defined sector of the migrating odontoblast layer. The arterioles pass through a cycle of proliferation, growth, remodeling, regression and decay, phase displaced in relation to each other. Proliferative and degenerative processes occur in the arteriole wall throughout the cycle, but vary considerably in intensity at different phases. Proliferation takes place by mitosis in the endothelium and the innermost smooth muscle cells. The degenerative process consists of reduction in size of smooth muscle cells by partial autodigestion and by cell death. When the odontoblasts reach the incisal extremity of the tooth, they die, and the associated regressed arteriole disappears. The system of pulpal arterioles has remarkable spatio-temporal features and each of its vessels appears to be in a state of sensitive structural equilibrium.
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Abstract
Continuously replicating organs are generally composed of several cell population types. These may be divided according to their function into two classes: 1. parenchyma: cells destined to perform a certain metabolic function peculiar to the organ under study, 2. supporting cell populations, consisting of fibroblasts and vascular supply always accompanied by nerve fibers. The kinetics of all the cells are highly coordinated. They all share one progenitor region. It is postulated that in this common progenitor region the two cell population classes are assembled into complex units denominated as proliferons. The proliferon starts its existence as a whole, matures as a whole and disintegrates at the organ periphery. It consists of four basic elements: parenchyma, connective tissue, blood vessels and nerve fibers. This model has been previously called upon to describe the kinetics of the rodent incisor tooth and the intestinal mucosa. It is assumed to be the elementary functional unit of all rapidly proliferating organs such as: skin, hair, endometrium, bone marrow, intestinal mucosa and rodent incisor.
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Orwin DF. The cytology and cytochemistry of the wool follicle. INTERNATIONAL REVIEW OF CYTOLOGY 1979; 60:331-74. [PMID: 574130 DOI: 10.1016/s0074-7696(08)61266-8] [Citation(s) in RCA: 79] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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