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Knuever J, Poeggeler B, Gáspár E, Klinger M, Hellwig-Burgel T, Hardenbicker C, Tóth BI, Bíró T, Paus R. Thyrotropin-releasing hormone controls mitochondrial biology in human epidermis. J Clin Endocrinol Metab 2012; 97:978-86. [PMID: 22259067 DOI: 10.1210/jc.2011-1096] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Mitochondrial capacity and metabolic potential are under the control of hormones, such as thyroid hormones. The most proximal regulator of the hypothalamic-pituitary-thyroid (HPT) axis, TRH, is the key hypothalamic integrator of energy metabolism via its impact on thyroid hormone secretion. OBJECTIVE Here, we asked whether TRH directly modulates mitochondrial functions in normal, TRH-receptor-positive human epidermis. METHODS Organ-cultured human skin was treated with TRH (5-100 ng/ml) for 12-48 h. RESULTS TRH significantly increased epidermal immunoreactivity for the mitochondria-selective subunit I of respiratory chain complex IV (MTCO1). This resulted from an increased MTCO1 transcription and protein synthesis and a stimulation of mitochondrial biogenesis as demonstrated by transmission electron microscopy and TRH-enhanced mitochondrial DNA synthesis. TRH also significantly stimulated the transcription of several other mitochondrial key genes (TFAM, HSP60, and BMAL1), including the master regulator of mitochondrial biogenesis (PGC-1α). TRH significantly enhanced mitochondrial complex I and IV enzyme activity and enhanced the oxygen consumption of human skin samples, which shows that the stimulated mitochondria are fully vital because the main source for cellular oxygen consumption is mitochondrial endoxidation. CONCLUSIONS These findings identify TRH as a potent, novel neuroendocrine stimulator of mitochondrial activity and biogenesis in human epidermal keratinocytes in situ. Thus, human epidermis offers an excellent model for dissecting neuroendocrine controls of human mitochondrial biology under physiologically relevant conditions and for exploring corresponding clinical applications.
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Affiliation(s)
- Jana Knuever
- Department of Dermatology, University of Luebeck, Ratzeburger Allee 160, D-23538 Luebeck, Germany
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TSH is a novel neuroendocrine regulator of selected keratins in the human hair follicle. J Dermatol Sci 2011; 64:67-70. [DOI: 10.1016/j.jdermsci.2011.06.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 06/13/2011] [Accepted: 06/15/2011] [Indexed: 11/23/2022]
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53
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Gáspár E, Nguyen-Thi KT, Hardenbicker C, Tiede S, Plate C, Bodó E, Knuever J, Funk W, Bíró T, Paus R. Thyrotropin-releasing hormone selectively stimulates human hair follicle pigmentation. J Invest Dermatol 2011; 131:2368-77. [PMID: 21956127 DOI: 10.1038/jid.2011.221] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In amphibians, thyrotropin-releasing hormone (TRH) stimulates skin melanophores by inducing secretion of α-melanocyte-stimulating hormone in the pituitary gland. However, it is unknown whether this tripeptide neurohormone exerts any direct effects on pigment cells, namely, on human melanocytes, under physiological conditions. Therefore, we have investigated whether TRH stimulates pigment production in organ-cultured human hair follicles (HFs), the epithelium of which expresses both TRH and its receptor, and/or in full-thickness human skin in situ. TRH stimulated melanin synthesis, tyrosinase transcription and activity, melanosome formation, melanocyte dendricity, gp100 immunoreactivity, and microphthalmia-associated transcription factor expression in human HFs in a pituitary gland-independent manner. TRH also stimulated proliferation, gp100 expression, tyrosinase activity, and dendricity of isolated human HF melanocytes. However, intraepidermal melanogenesis was unaffected. As TRH upregulated the intrafollicular production of "pituitary" neurohormones (proopiomelanocortin transcription and ACTH immunoreactivity) and as agouti-signaling protein counteracted TRH-induced HF pigmentation, these pigmentary TRH effects may be mediated in part by locally generated melanocortins and/or by MC-1 signaling. Our study introduces TRH as a novel, potent, selective, and evolutionarily highly conserved neuroendocrine factor controlling human pigmentation in situ. This physiologically relevant and melanocyte sub-population-specific neuroendocrine control of human pigmentation deserves clinical exploration, e.g., for preventing or reversing hair graying.
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Affiliation(s)
- Erzsébet Gáspár
- Department of Dermatology, University of Lübeck, Lübeck, Germany
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54
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García-Serrano L, Gomez-Ferrería MA, Contreras-Jurado C, Segrelles C, Paramio JM, Aranda A. The thyroid hormone receptors modulate the skin response to retinoids. PLoS One 2011; 6:e23825. [PMID: 21858227 PMCID: PMC3157470 DOI: 10.1371/journal.pone.0023825] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 07/27/2011] [Indexed: 12/27/2022] Open
Abstract
Background Retinoids play an important role in skin homeostasis and when administered topically cause skin hyperplasia, abnormal epidermal differentiation and inflammation. Thyroidal status in humans also influences skin morphology and function and we have recently shown that the thyroid hormone receptors (TRs) are required for a normal proliferative response to 12-O-tetradecanolyphorbol-13-acetate (TPA) in mice. Methodology/Principal findings We have compared the epidermal response of mice lacking the thyroid hormone receptor binding isoforms TRα1 and TRβ to retinoids and TPA. Reduced hyperplasia and a decreased number of proliferating cells in the basal layer in response to 9-cis-RA and TPA were found in the epidermis of TR-deficient mice. Nuclear levels of proteins important for cell proliferation were altered, and expression of keratins 5 and 6 was also reduced, concomitantly with the decreased number of epidermal cell layers. In control mice the retinoid (but not TPA) induced parakeratosis and diminished expression of keratin 10 and loricrin, markers of early and terminal epidermal differentiation, respectively. This reduction was more accentuated in the TR deficient animals, whereas they did not present parakeratosis. Therefore, TRs modulate both the proliferative response to retinoids and their inhibitory effects on skin differentiation. Reduced proliferation, which was reversed upon thyroxine treatment, was also found in hypothyroid mice, demonstrating that thyroid hormone binding to TRs is required for the normal response to retinoids. In addition, the mRNA levels of the pro-inflammatory cytokines TNFα and IL-6 and the chemotactic proteins S1008A and S1008B were significantly elevated in the skin of TR knock-out mice after TPA or 9-cis-RA treatment and immune cell infiltration was also enhanced. Conclusions/significance Since retinoids are commonly used for the treatment of skin disorders, these results demonstrating that TRs regulate skin proliferation, differentiation and inflammation in response to these compounds could have not only physiological but also therapeutic implications.
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Affiliation(s)
- Laura García-Serrano
- Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
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55
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Borbíró I, Lisztes E, Tóth BI, Czifra G, Oláh A, Szöllősi AG, Szentandrássy N, Nánási PP, Péter Z, Paus R, Kovács L, Bíró T. Activation of Transient Receptor Potential Vanilloid-3 Inhibits Human Hair Growth. J Invest Dermatol 2011; 131:1605-14. [DOI: 10.1038/jid.2011.122] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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56
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Atkinson S, Arnould JPY, Mashburn KL. Plasma cortisol and thyroid hormone concentrations in pre-weaning Australian fur seal pups. Gen Comp Endocrinol 2011; 172:277-81. [PMID: 21439286 DOI: 10.1016/j.ygcen.2011.03.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 03/15/2011] [Accepted: 03/16/2011] [Indexed: 10/18/2022]
Abstract
The hormonal factors that influence development from birth to weaning in otariid seals is still largely unknown. In the present study, a suite of thyroid hormones and cortisol were measured in Australian fur seal pups in order to determine baseline concentrations as well as to describe their endocrinology over this critical developmental period. A cross-section of newborn pups from a breeding colony located on Kanowna Island, Australia were sampled at six different times over the course of the 10 month lactation period. Sample times were designed to correspond to periods of heightened physiological change during pre-weaning development: post-natal, pre-molt, the initiation of molt, mid-molt, period of peak milk intake and weaning. Results indicate that the greatest hormonal changes were associated with the post-natal stage and molt, with molt showing the greatest changes, as has been reported for several species of pinnipeds. Two forms of thyroid hormones analyzed (Total T(4), and Free T(3)), increased with the initiation of the molt, and Free T(3) exhibited a second increase that was associated with the period of peak milk intake. The T(3):T(4) ratio was significantly lower during the initiation of molt than either pre- or mid-molt. The study was able to describe physiological change during the first year of life in Australian fur seals as well as document basal concentrations of thyroid hormones and cortisol in pups of this species.
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Affiliation(s)
- S Atkinson
- University of Alaska Fairbanks, School of Fisheries and Ocean Sciences, Fisheries Division, Juneau Center, Juneau, Alaska 99801, USA.
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57
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Contreras-Jurado C, García-Serrano L, Gómez-Ferrería M, Costa C, Paramio JM, Aranda A. The thyroid hormone receptors as modulators of skin proliferation and inflammation. J Biol Chem 2011; 286:24079-88. [PMID: 21566120 DOI: 10.1074/jbc.m111.218487] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
We have analyzed the role of the thyroid hormone receptors (TRs) in epidermal homeostasis. Reduced keratinocyte proliferation is found in interfollicular epidermis of mice lacking the thyroid hormone binding isoforms TRα1 and TRβ (KO mice). Similar results were obtained in hypothyroid animals, showing the important role of the liganded TRs in epidermal proliferation. In addition, KO and hypothyroid animals display decreased hyperplasia in response to 12-O-tetradecanolyphorbol-13-acetate. Both receptor isoforms play overlapping functional roles in the skin because mice lacking individually TRα1 or TRβ also present a proliferative defect but not as marked as that found in double KO mice. Defective proliferation in KO mice is associated with reduction of cyclin D1 expression and up-regulation of the cyclin-dependent kinase inhibitors p19 and p27. Paradoxically, ERK and AKT activity and expression of downstream targets, such as AP-1 components, are increased in KO mice. Increased p65/NF-κB and STAT3 phosphorylation and, as a consequence, augmented expression of chemokines and proinflammatory cytokines is also found in these animals. These results show that thyroid hormones and their receptors are important mediators of skin proliferation and demonstrate that TRs act as endogenous inhibitors of skin inflammation, most likely due to interference with AP-1, NF-κB, and STAT3 activation.
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Affiliation(s)
- Constanza Contreras-Jurado
- Instituto de Investigaciones Biomédicas de Madrid, Consejo Superior de Investigaciones Científicas, and Universidad Autónoma de Madrid, 28029 Madrid, Spain
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58
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Abstract
The role of neurohormones and neuropeptides in human hair follicle (HF) pigmentation extends far beyond the control of melanin synthesis by α-MSH and ACTH and includes melanoblast differentiation, reactive oxygen species scavenging, maintenance of HF immune privilege, and remodeling of the HF pigmentary unit (HFPU). It is now clear that human HFs are not only a target of multiple neuromediators, but also are a major non-classical production site for neurohormones such as CRH, proopiomelanocortin, ACTH, α-MSH, ß-endorphin, TRH, and melatonin. Moreover, human HFs have established a functional peripheral equivalent of the hypothalamic-pituitary-adrenal axis. By charting the author's own meanderings through the jungle of hair pigmentation research, the current perspectives essay utilizes four clinical observations - hair repigmentation, canities, poliosis, and 'overnight greying'- as points of entry into the enigmas and challenges of .pigmentary HF neuroendocrinology. After synthesizing key principles and defining major open questions in the field, selected research avenues are delineated that appear clinically most promising. In this context, novel neuroendocrinological strategies to retard or reverse greying and to reduce damage to the HFPU are discussed.
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Affiliation(s)
- Ralf Paus
- Department of Dermatology, University of Lübeck, Lübeck, Germany.
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59
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Abstract
The TSH receptor expressed on the cell surface of thyroid follicular cells plays a pivotal role in the regulation of thyroid status and growth of the thyroid gland. In recent years it has become evident that the TSH receptor is also expressed widely in a variety of extrathyroidal tissues including: anterior pituitary; hypothalamus; ovary; testis; skin; kidney; immune system; bone marrow and peripheral blood cells; white and brown adipose tissue; orbital preadipocyte fibroblasts and bone. A large body of evidence is emerging to describe the functional roles of the TSH receptor at these various sites but their physiological importance in many cases remains a subject of controversy and much interest. Current understanding of the actions of the TSH receptor in extrathyroidal tissues and their possible physiological implications is discussed.
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Affiliation(s)
- G R Williams
- Molecular Endocrinology Group, Hammersmith Hospital, London, UK.
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60
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Abstract
With respect to the relationship between hormones and hair growth, the role of androgens for androgenetic alopecia (AGA) and hirsutism is best acknowledged. Accordingly, therapeutic strategies that intervene in androgen metabolism have been successfully developed for treatment of these conditions. Clinical observations of hair conditions involving hormones beyond the androgen horizon have determined their role in regulation of hair growth: estrogens, prolactin, thyroid hormone, cortisone, growth hormone (GH), and melatonin. Primary GH resistance is characterized by thin hair, while acromegaly may cause hypertrichosis. Hyperprolactinemia may cause hair loss and hirsutism. Partial synchronization of the hair cycle in anagen during late pregnancy points to an estrogen effect, while aromatase inhibitors cause hair loss. Hair loss in a causal relationship to thyroid disorders is well documented. In contrast to AGA, senescent alopecia affects the hair in a diffuse manner. The question arises, whether the hypothesis that a causal relationship exists between the age-related reduction of circulating hormones and organ function also applies to hair and the aging of hair.
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Affiliation(s)
- R M Trüeb
- Dermatologische Klinik, Universitätsspital Zürich, Gloriastr. 31, 8091, Zürich, Switzerland.
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61
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HaCaT keratinocytes express functional receptors for thyroid-stimulating hormone. J Dermatol Sci 2010; 59:52-5. [DOI: 10.1016/j.jdermsci.2010.04.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 03/30/2010] [Accepted: 04/16/2010] [Indexed: 11/18/2022]
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62
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Bodó E, Kany B, Gáspár E, Knüver J, Kromminga A, Ramot Y, Bíró T, Tiede S, van Beek N, Poeggeler B, Meyer KC, Wenzel BE, Paus R. Thyroid-stimulating hormone, a novel, locally produced modulator of human epidermal functions, is regulated by thyrotropin-releasing hormone and thyroid hormones. Endocrinology 2010; 151:1633-42. [PMID: 20176727 DOI: 10.1210/en.2009-0306] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Several elements of the hypothalamic-pituitary-thyroid axis (HPT) reportedly are transcribed by human skin cell populations, and human hair follicles express functional receptors for TSH. Therefore, we asked whether the epidermis of normal human skin is yet another extrathyroidal target of TSH and whether epidermis even produces TSH. If so, we wanted to clarify whether intraepidermal TSH expression is regulated by TRH and/or thyroid hormones and whether TSH alters selected functions of normal human epidermis in situ. TSH and TSH receptor (TSH-R) expression were analyzed in the epidermis of normal human scalp skin by immunohistochemistry and PCR. In addition, full-thickness scalp skin was organ cultured and treated with TSH, TRH, or thyroid hormones, and the effect of TSH treatment on the expression of selected genes was measured by quantitative PCR and/or quantitative immunohistochemistry. Here we show that normal human epidermis expresses TSH at the mRNA and protein levels in situ and transcribes TSH-R. It also contains thyrostimulin transcripts. Intraepidermal TSH immunoreactivity is up-regulated by TRH and down-regulated by thyroid hormones. Although TSH-R immunoreactivity in situ could not be documented within the epidermis, but in the immediately adjacent dermis, TSH treatment of organ-cultured human skin strongly up-regulated epidermal expression of involucrin, loricrin, and keratins 5 and 14. Thus, normal human epidermis in situ is both an extrapituitary source and (possibly an indirect) target of TSH signaling, which regulates defined epidermal parameters. Intraepidermal TSH expression appears to be regulated by the classical endocrine controls that determine the systemic HPT axis.
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Affiliation(s)
- Eniko Bodó
- Department of Dermatology, University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany
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63
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Cianfarani F, Baldini E, Cavalli A, Marchioni E, Lembo L, Teson M, Persechino S, Zambruno G, Ulisse S, Odorisio T, D'Armiento M. TSH receptor and thyroid-specific gene expression in human skin. J Invest Dermatol 2010; 130:93-101. [PMID: 19641516 DOI: 10.1038/jid.2009.180] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Experimental evidence suggests that in autoimmune thyroid diseases (AITDs) the skin is a target of autoantibodies against thyroid-specific antigens; however, the role of these autoantibodies in skin alterations remains unclear. To gain insight into the function of nominally thyroid-specific genes in skin, we analyzed the expression of thyroid-stimulating hormone-receptor (TSH-R), thyroglobulin (Tg), sodium iodide symporter (NIS), and thyroperoxidase (TPO) genes in normal human skin biopsies and cultured primary keratinocytes and dermal fibroblasts. The results revealed the presence of all the transcripts in skin biopsies. However, in keratinocytes and fibroblasts, only TSH-R messenger RNA was always detected. Western blot and immunohistochemical analyses of skin specimens confirmed the presence of TSH-R protein in keratinocytes and fibroblasts. Moreover, TSH treatment induced the proliferation of cultured keratinocytes and fibroblasts and increased keratinocyte intracellular cAMP. Finally, affinity-purified IgGs from serum of patients affected by Graves' disease, but not by chronic lymphocytic thyroiditis, stimulated cAMP accumulation in cultured keratinocytes, as well as their proliferation. In conclusion, the expression of thyroid-specific genes in cultured keratinocytes and fibroblasts and the mitogenic effects of TSH and IgGs on these cells support the concept that autoantibodies against thyroid-specific antigens may contribute to cutaneous symptoms in AITDs.
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Affiliation(s)
- Francesca Cianfarani
- Laboratory of Molecular and Cell Biology, Istituto Dermopatico dell'Immacolata-IRCCS, Rome, Italy
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64
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Ramot Y, Bíró T, Tiede S, Tóth BI, Langan EA, Sugawara K, Foitzik K, Ingber A, Goffin V, Langbein L, Paus R. Prolactin--a novel neuroendocrine regulator of human keratin expression in situ. FASEB J 2010; 24:1768-79. [PMID: 20103718 DOI: 10.1096/fj.09-146415] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The controls of human keratin expression in situ remain to be fully elucidated. Here, we have investigated the effects of the neurohormone prolactin (PRL) on keratin expression in a physiologically and clinically relevant test system: organ-cultured normal human hair follicles (HFs). Not only do HFs express a wide range of keratins, but they are also a source and target of PRL. Microarray analysis revealed that PRL differentially regulated a defined subset of keratins and keratin-associated proteins. Quantitative immunohistomorphometry and quantitative PCR confirmed that PRL up-regulated expression of keratins K5 and K14 and the epithelial stem cell-associated keratins K15 and K19 in organ-cultured HFs and/or isolated HF keratinocytes. PRL also up-regulated K15 promoter activity and K15 protein expression in situ, whereas it inhibited K6 and K31 expression. These regulatory effects were reversed by a pure competitive PRL receptor antagonist. Antagonist alone also modulated keratin expression, suggesting that "tonic stimulation" by endogenous PRL is required for normal expression levels of selected keratins. Therefore, our study identifies PRL as a major, clinically relevant, novel neuroendocrine regulator of both human keratin expression and human epithelial stem cell biology in situ.
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Affiliation(s)
- Yuval Ramot
- Department of Dermatology, University of Lübeck, Lübeck, Germany
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65
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Poeggeler B, Knuever J, Gáspár E, Bíró T, Klinger M, Bodo E, Wiesner RJ, Wenzel BE, Paus R. Thyrotropin powers human mitochondria. FASEB J 2010; 24:1525-31. [DOI: 10.1096/fj.09-147728] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
| | | | | | - Tamás Bíró
- Department of PhysiologyUniversity of DebrecenDebrecenHungary
- Abiol LtdDebrecenHungary
| | | | | | - Rudolf J. Wiesner
- Department of Vegetative PhysiologyUniversity of CologneCologneGermany
- Cologne Excellence Cluster: Cellular Stress Responses in Aging‐Associated Diseases (CECAD)CologneGermany
- Center for Molecular Medicine Cologne (CMMC)CologneGermany
| | | | - Ralf Paus
- Department of DermatologyGermany
- School of Translational MedicineUniversity of ManchesterManchesterUK
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66
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Exploring the “Thyroid–Skin Connection”: Concepts, Questions, and Clinical Relevance. J Invest Dermatol 2010; 130:7-10. [DOI: 10.1038/jid.2009.359] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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67
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Li JJ, Mitchell LH, Dow RL. Thyroid receptor agonists for the treatment of androgenetic alopecia. Bioorg Med Chem Lett 2009; 20:306-8. [PMID: 19900809 DOI: 10.1016/j.bmcl.2009.10.109] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Revised: 10/22/2009] [Accepted: 10/26/2009] [Indexed: 11/25/2022]
Abstract
A thyroid hormone receptor beta subtype-selective thyromimetic 5 was found to be efficacious in both mouse and monkey hair growth models after topical applications. It penetrates the skin according to the test in human cadaver skin mounted onto Franz diffusion chambers. The serum drug level of 5 is below the limit of quantification during tests in the bald stump-tailed macaques (Macaca arctoides). It is tested negative in the 3T3 neutral red uptake (NRU) phototoxicity test, indicating a low risk for causing photo-irritation. It is also rapidly metabolized according to the PK data, thus the systemic exposure is limited.
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Affiliation(s)
- Jie Jack Li
- Department of Chemistry, Michigan Laboratories, Pfizer Global Research & Development, 2800 Plymouth Road, Ann Arbor, MI 48105, United States.
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68
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Poeggeler B, Schulz C, Pappolla MA, Bodó E, Tiede S, Lehnert H, Paus R. Leptin and the skin: a new frontier. Exp Dermatol 2009; 19:12-8. [PMID: 19601981 DOI: 10.1111/j.1600-0625.2009.00930.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Here, we examine the currently available information which supports that the adipokine, leptin, is a major player in the biology and pathology of mammalian skin and its appendages. Specifically, the potent metabolic effects of leptin and its mimetics may be utilized to improve, preserve and restore skin regeneration and hair cycle progression, and may halt or even partially reverse some aspects of skin ageing. Since leptin can enhance mitochondrial activity and biogenesis, this may contribute to the wound healing-promoting and hair growth-modulatory effects of leptin. Leptin dependent intracellular signalling by the Janus kinase 2 dependent signal transducer and activator of transcription 3, adenosine monophosphate kinase, and peroxisome proliferator-activated receptor (PPAR) gamma coactivator/PPAR converges to mediate mitochondrial metabolic activation and enhanced cell proliferation which may orchestrate the potent developmental, trophic and protective effects of leptin. Since leptin and leptin mimetics have already been clinically tested, investigative dermatology is well-advised to place greater emphasis on the systematic exploration of the cutaneous dimensions and dermatological potential of this pleiotropic hormone.
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69
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Ramot Y, Paus R, Tiede S, Zlotogorski A. Endocrine controls of keratin expression. Bioessays 2009; 31:389-99. [DOI: 10.1002/bies.200800121] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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