1
|
Logesh R, Prasad SR, Chipurupalli S, Robinson N, Mohankumar SK. Natural tyrosinase enzyme inhibitors: A path from melanin to melanoma and its reported pharmacological activities. Biochim Biophys Acta Rev Cancer 2023; 1878:188968. [PMID: 37657683 DOI: 10.1016/j.bbcan.2023.188968] [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: 01/18/2023] [Revised: 08/15/2023] [Accepted: 08/15/2023] [Indexed: 09/03/2023]
Abstract
The skin containing melanin pigment acts as a protective barrier and counteracts the UVR and other environmental stressors to maintain or restore disrupted cutaneous homeostasis. The production of melanin pigment is dependent on tyrosine levels. L-tyrosine and L-dihydroxyphenylalanine (L-DOPA) can serve both as a substrates and intermediates of melanin synthetic pathway and as inducers and positive regulators of melanogenesis. The biosynthesis of melanin is stimulated upon exposure to UVR, which can also stimulate local production of hormonal factors, which can stimulate melanoma development by altering the chemical properties of eu- and pheomelanin. The process of melanogenesis can be altered by several pathways. One involves activation of POMC, with the production of POMC peptides including MSH and ACTH, which increase intracellular cAMP levels, which activates the MITF, and helps to stimulate tyrosinase (TYR) expression and activity. Defects in OCA1 to 4 affects melanogenic activity via posttranslational modifications resulting in proteasomal degradation and reducing pigmentation. Further, altering, the MITF factor, helps to regulate the expression of MRGE in melanoma, and helps to increase the TYR glycosylation in ER. CRH stimulates POMC peptides that regulate melanogenesis and also by itself can stimulate melanogenesis. The POMC, P53, ACTH, MSH, MC1R, MITF, and 6-BH4 are found to be important regulators for pigmentation. Melanogenesis can affect melanoma behaviour and inhibit immune responses. Therefore, we reviewed natural products that would alter melanin production. Our special focus was on targeting melanin synthesis and TYR enzyme activity to inhibit melanogenesis as an adjuvant therapy of melanotic melanoma. Furthermore, this review also outlines the current updated pharmacological studies targeting the TYR enzyme from natural sources and its consequential effects on melanin production.
Collapse
Affiliation(s)
- Rajan Logesh
- Department of Pharmacognosy, JSS College of Pharmacy, JSS Academy of Higher Education and Research, Mysuru 570015, Karnataka, India.
| | - Sagar Rajendra Prasad
- Department of Pharmacognosy, Varadaraja Institute of Pharmaceutical Education and Research, Tumkur 572102, Karnataka, India
| | - Sandhya Chipurupalli
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education and Research, Ooty, India
| | - Nirmal Robinson
- Cellular Stress and Immune Response Laboratory, Centre for Cancer Biology, University of South Australia, Adelaide, Australia
| | - Suresh Kumar Mohankumar
- Pharmacy, Swansea University Medical School, Singleton Park, Swansea University, Wales SA2 8PP, United Kingdom
| |
Collapse
|
2
|
Slominski AT, Slominski RM, Raman C, Chen JY, Athar M, Elmets C. Neuroendocrine signaling in the skin with a special focus on the epidermal neuropeptides. Am J Physiol Cell Physiol 2022; 323:C1757-C1776. [PMID: 36317800 PMCID: PMC9744652 DOI: 10.1152/ajpcell.00147.2022] [Citation(s) in RCA: 63] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 10/21/2022] [Accepted: 10/21/2022] [Indexed: 11/07/2022]
Abstract
The skin, which is comprised of the epidermis, dermis, and subcutaneous tissue, is the largest organ in the human body and it plays a crucial role in the regulation of the body's homeostasis. These functions are regulated by local neuroendocrine and immune systems with a plethora of signaling molecules produced by resident and immune cells. In addition, neurotransmitters, endocrine factors, neuropeptides, and cytokines released from nerve endings play a central role in the skin's responses to stress. These molecules act on the corresponding receptors in an intra-, juxta-, para-, or autocrine fashion. The epidermis as the outer most component of skin forms a barrier directly protecting against environmental stressors. This protection is assured by an intrinsic keratinocyte differentiation program, pigmentary system, and local nervous, immune, endocrine, and microbiome elements. These constituents communicate cross-functionally among themselves and with corresponding systems in the dermis and hypodermis to secure the basic epidermal functions to maintain local (skin) and global (systemic) homeostasis. The neurohormonal mediators and cytokines used in these communications regulate physiological skin functions separately or in concert. Disturbances in the functions in these systems lead to cutaneous pathology that includes inflammatory (i.e., psoriasis, allergic, or atopic dermatitis, etc.) and keratinocytic hyperproliferative disorders (i.e., seborrheic and solar keratoses), dysfunction of adnexal structure (i.e., hair follicles, eccrine, and sebaceous glands), hypersensitivity reactions, pigmentary disorders (vitiligo, melasma, and hypo- or hyperpigmentary responses), premature aging, and malignancies (melanoma and nonmelanoma skin cancers). These cellular, molecular, and neural components preserve skin integrity and protect against skin pathologies and can act as "messengers of the skin" to the central organs, all to preserve organismal survival.
Collapse
Affiliation(s)
- Andrzej T Slominski
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama
- Comprehensive Cancer Center, Cancer Chemoprevention Program, University of Alabama at Birmingham, Birmingham, Alabama
- VA Medical Center, Birmingham, Alabama
| | - Radomir M Slominski
- Graduate Biomedical Sciences Program, University of Alabama at Birmingham, Birmingham, Alabama
| | - Chander Raman
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Jake Y Chen
- Informatics Institute, University of Alabama at Birmingham, Birmingham, Alabama
| | - Mohammad Athar
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama
- VA Medical Center, Birmingham, Alabama
| | - Craig Elmets
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, Alabama
- Comprehensive Cancer Center, Cancer Chemoprevention Program, University of Alabama at Birmingham, Birmingham, Alabama
- VA Medical Center, Birmingham, Alabama
| |
Collapse
|
3
|
Romero-Leguizamón CR, Kohlmeier KA. Stress-related endogenous neuropeptides induce neuronal excitation in the Laterodorsal Tegmentum. Eur Neuropsychopharmacol 2020; 38:86-97. [PMID: 32768153 DOI: 10.1016/j.euroneuro.2020.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 05/29/2020] [Accepted: 07/16/2020] [Indexed: 01/07/2023]
Abstract
Stress is a physiological response that promotes maintenance of balance against harmful stimuli. Unfortunately, chronic activation of stress systems facilitates the development of psychiatric disorders. A stress-mediated hypercholinergic state could underlie this facilitation, as cholinergic mechanisms have been suggested to play a role in anxiety, depression, and substance use disorder (SUD). Stimulation by stress hormones, urocortin (Ucn1) or corticotropin-releasing factor (CRF), of the CRF receptor type 1 (CRFR1) of acetylcholine-containing neurons of the laterodorsal tegmental nucleus (LDT) could be involved in modulation of cholinergic transmission during periods of stress hormone activation, which could play a role in psychiatric disorders as cholinergic LDT neurons project to, and control activity in, mood-, arousal- and SUD-controlling regions. The present study investigated for the first time the membrane effects and intracellular outcomes of CRFR1 activation by endogenous stress hormones on LDT neurons. Patch clamp recordings of immunohistochemically-identified cholinergic and non-cholinergic LDT neurons with concurrent calcium imaging were used to monitor cellular responses to CRFR1 stimulation with Ucn1 and CRF. Postsynaptically-mediated excitatory currents were elicited in LDT cholinergic neurons, accompanied by an enhancement in synaptic events. In addition, CRFR1 activation resulted in rises in intracellular calcium levels. CRFR1 stimulation recruited MAPK/ERK and SERCA-ATPase involved pathways. The data presented here provide the first evidence that Ucn1 and CRF exert pre and postsynaptic excitatory membrane actions on LDT cholinergic neurons that could underlie the hypercholinergic state associated with stress which could play a role in the heightened risk of psychiatric disorders associated with a chronic stress state.
Collapse
Affiliation(s)
- Cesar R Romero-Leguizamón
- Department of Drug Design and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Kristi A Kohlmeier
- Department of Drug Design and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, 2100, Denmark.
| |
Collapse
|
4
|
Clayton RW, Langan EA, Ansell DM, de Vos IJHM, Göbel K, Schneider MR, Picardo M, Lim X, van Steensel MAM, Paus R. Neuroendocrinology and neurobiology of sebaceous glands. Biol Rev Camb Philos Soc 2020; 95:592-624. [PMID: 31970855 DOI: 10.1111/brv.12579] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 12/17/2019] [Accepted: 12/19/2019] [Indexed: 12/11/2022]
Abstract
The nervous system communicates with peripheral tissues through nerve fibres and the systemic release of hypothalamic and pituitary neurohormones. Communication between the nervous system and the largest human organ, skin, has traditionally received little attention. In particular, the neuro-regulation of sebaceous glands (SGs), a major skin appendage, is rarely considered. Yet, it is clear that the SG is under stringent pituitary control, and forms a fascinating, clinically relevant peripheral target organ in which to study the neuroendocrine and neural regulation of epithelia. Sebum, the major secretory product of the SG, is composed of a complex mixture of lipids resulting from the holocrine secretion of specialised epithelial cells (sebocytes). It is indicative of a role of the neuroendocrine system in SG function that excess circulating levels of growth hormone, thyroxine or prolactin result in increased sebum production (seborrhoea). Conversely, growth hormone deficiency, hypothyroidism, and adrenal insufficiency result in reduced sebum production and dry skin. Furthermore, the androgen sensitivity of SGs appears to be under neuroendocrine control, as hypophysectomy (removal of the pituitary) renders SGs largely insensitive to stimulation by testosterone, which is crucial for maintaining SG homeostasis. However, several neurohormones, such as adrenocorticotropic hormone and α-melanocyte-stimulating hormone, can stimulate sebum production independently of either the testes or the adrenal glands, further underscoring the importance of neuroendocrine control in SG biology. Moreover, sebocytes synthesise several neurohormones and express their receptors, suggestive of the presence of neuro-autocrine mechanisms of sebocyte modulation. Aside from the neuroendocrine system, it is conceivable that secretion of neuropeptides and neurotransmitters from cutaneous nerve endings may also act on sebocytes or their progenitors, given that the skin is richly innervated. However, to date, the neural controls of SG development and function remain poorly investigated and incompletely understood. Botulinum toxin-mediated or facial paresis-associated reduction of human sebum secretion suggests that cutaneous nerve-derived substances modulate lipid and inflammatory cytokine synthesis by sebocytes, possibly implicating the nervous system in acne pathogenesis. Additionally, evidence suggests that cutaneous denervation in mice alters the expression of key regulators of SG homeostasis. In this review, we examine the current evidence regarding neuroendocrine and neurobiological regulation of human SG function in physiology and pathology. We further call attention to this line of research as an instructive model for probing and therapeutically manipulating the mechanistic links between the nervous system and mammalian skin.
Collapse
Affiliation(s)
- Richard W Clayton
- Centre for Dermatology, School of Biological Sciences, University of Manchester, and NIHR Manchester Biomedical Research Centre, Stopford Building, Oxford Road, Manchester, M13 9PT, U.K.,Skin Research Institute of Singapore, Agency for Science, Technology and Research, 11 Mandalay Road, #17-01 Clinical Sciences Building, 308232, Singapore
| | - Ewan A Langan
- Centre for Dermatology, School of Biological Sciences, University of Manchester, and NIHR Manchester Biomedical Research Centre, Stopford Building, Oxford Road, Manchester, M13 9PT, U.K.,Department of Dermatology, Allergology und Venereology, University of Lübeck, Ratzeburger Allee 160, Lübeck, 23538, Germany
| | - David M Ansell
- Centre for Dermatology, School of Biological Sciences, University of Manchester, and NIHR Manchester Biomedical Research Centre, Stopford Building, Oxford Road, Manchester, M13 9PT, U.K.,Division of Cell Matrix Biology and Regenerative Medicine, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, U.K
| | - Ivo J H M de Vos
- Skin Research Institute of Singapore, Agency for Science, Technology and Research, 11 Mandalay Road, #17-01 Clinical Sciences Building, 308232, Singapore
| | - Klaus Göbel
- Skin Research Institute of Singapore, Agency for Science, Technology and Research, 11 Mandalay Road, #17-01 Clinical Sciences Building, 308232, Singapore.,Department of Dermatology, Cologne Excellence Cluster on Stress Responses in Aging Associated Diseases (CECAD), and Centre for Molecular Medicine Cologne, The University of Cologne, Joseph-Stelzmann-Straße 26, Cologne, 50931, Germany
| | - Marlon R Schneider
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Max-Dohrn-Straße 8-10, Berlin, 10589, Germany
| | - Mauro Picardo
- Cutaneous Physiopathology and Integrated Centre of Metabolomics Research, San Gallicano Dermatological Institute IRCCS, Via Elio Chianesi 53, Rome, 00144, Italy
| | - Xinhong Lim
- Lee Kong Chian School of Medicine, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Maurice A M van Steensel
- Skin Research Institute of Singapore, Agency for Science, Technology and Research, 11 Mandalay Road, #17-01 Clinical Sciences Building, 308232, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Ralf Paus
- Centre for Dermatology, School of Biological Sciences, University of Manchester, and NIHR Manchester Biomedical Research Centre, Stopford Building, Oxford Road, Manchester, M13 9PT, U.K.,Dr. Phllip Frost Department of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, 1600 NW 10th Avenue, RMSB 2023A, Miami, FL, 33136, U.S.A.,Monasterium Laboratory, Mendelstraße 17, Münster, 48149, Germany
| |
Collapse
|
5
|
Chang YJ, Lee DU, Nam JH, Kim WK. Inhibitory Effect of A
grimonia Pilosa
Leaf Extract on the UV-Induced Photoaging-Related Ion Channel, ORAI1, and the Enzymes Tyrosinase and Elastase. J Food Biochem 2015. [DOI: 10.1111/jfbc.12171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- You-Jin Chang
- Department of Korean Medical Ophthalmology & Otolaryngology & Dermatology; Dongguk University College of Korean Medicine; Ilsan Dong-gu Goyang Gyeonggi-do Korea
| | - Dong-Ung Lee
- Division of Bioscience; Dongguk University; Gyeongju Gyeongsangbuk-do Korea
| | - Joo Hyun Nam
- Department of Physiology; Dongguk University College of Medicine; Gyeongju Gyeongsangbuk-do Korea
- Channelopathy Research Center (CRC); Dongguk University College of Medicine; 32 Dongguk-ro Ilsan Dong-gu Goyang Gyeonggi-do 410-773 Korea
| | - Woo Kyung Kim
- Channelopathy Research Center (CRC); Dongguk University College of Medicine; 32 Dongguk-ro Ilsan Dong-gu Goyang Gyeonggi-do 410-773 Korea
- Department of Internal Medicine Graduate School of Medicine; Dongguk University; 27 Dongguk-ro Ilsan Dong-gu Goyang Gyeonggi-do 410-773 Korea
| |
Collapse
|
6
|
García-Carmona JA, Camejo DM, Almela P, Jiménez A, Milanés MV, Sevilla F, Laorden ML. CP-154,526 Modifies CREB Phosphorylation and Thioredoxin-1 Expression in the Dentate Gyrus following Morphine-Induced Conditioned Place Preference. PLoS One 2015; 10:e0136164. [PMID: 26313266 PMCID: PMC4551807 DOI: 10.1371/journal.pone.0136164] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 07/31/2015] [Indexed: 12/31/2022] Open
Abstract
Corticotropin-releasing factor (CRF) acts as neuro-regulator of the behavioral and emotional integration of environmental and endogenous stimuli associated with drug dependence. Thioredoxin-1 (Trx-1) is a functional protein controlling the redox status of several proteins, which is involved in addictive processes. In the present study, we have evaluated the role of CRF1 receptor (CRF1R) in the rewarding properties of morphine by using the conditioned place preference (CPP) paradigm. We also investigate the effects of the CRF1R antagonist, CP-154,526, on the morphine CPP-induced activation of CRF neurons, CREB phosphorylation and Trx expression in paraventricular nucleus (PVN) and dentate gyrus (DG) of the mice brain. CP-154,526 abolished the acquisition of morphine CPP and the increase of CRF/pCREB positive neurons in PVN. Moreover, this CRF1R antagonist prevented morphine-induced CRF-immunoreactive fibers in DG, as well as the increase in pCREB expression in both the PVN and DG. In addition, morphine exposure induced an increase in Trx-1 expression in DG without any alterations in PVN. We also observed that the majority of pCREB positive neurons in DG co-expressed Trx-1, suggesting that Trx-1 could activate CREB in the DG, a brain region involved in memory consolidation. Altogether, these results support the idea that CRF1R antagonist blocked Trx-1 expression and pCREB/Trx-1 co-localization, indicating a critical role of CRF, through CRF1R, in molecular changes involved in morphine associated behaviors.
Collapse
Affiliation(s)
| | - Daymi M. Camejo
- Department of Stress Biology and Plant Pathology, CEBAS-CSIC, Murcia, Spain
| | - Pilar Almela
- Department of Pharmacology, Faculty of Medicine, University of Murcia, Murcia, Spain
- * E-mail:
| | - Ana Jiménez
- Department of Stress Biology and Plant Pathology, CEBAS-CSIC, Murcia, Spain
| | | | - Francisca Sevilla
- Department of Stress Biology and Plant Pathology, CEBAS-CSIC, Murcia, Spain
| | - María-Luisa Laorden
- Department of Pharmacology, Faculty of Medicine, University of Murcia, Murcia, Spain
| |
Collapse
|
7
|
Barui A, Khare R, Dhara S, Banerjee P, Chatterjee J. Ex vivo bio-compatibility of honey-alginate fibrous matrix for HaCaT and 3T3 with prime molecular expressions. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2014; 25:2659-2667. [PMID: 22042457 DOI: 10.1007/s10856-011-4456-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Accepted: 10/02/2011] [Indexed: 05/31/2023]
Abstract
Honey's inherent compositional diversity, bio-compatibility and time tested therapeutic efficacy, especially in tissue repair as a topical agent, attract researchers towards harnessing its biomaterial potential particularly in developing matrix for tissue engineering applications. Hence, this study fabricates fibrous mat from optimum honey-alginate formulation and alginate solution using wet spinning technology. The physical and morphological properties of the scaffolds are assessed and finally their comparative biological performances are evaluated through in vitro studies on adherence, viability and prime molecular expression of HaCaT and 3T3 cells. The honey-alginate scaffold demonstrates better performance than that of alginate in terms of cellular adherence, viability and proper expression of cell-cell adhesion molecule (E-cadherin) and prime molecules of extra cellular matrix (Collagen I and III) by HaCaT and 3T3 respectively.
Collapse
Affiliation(s)
- Ananya Barui
- School of Medical Science & Technology, IIT Kharagpur, Kharagpur, 721302, India
| | | | | | | | | |
Collapse
|
8
|
Slominski AT, Zmijewski MA, Zbytek B, Tobin DJ, Theoharides TC, Rivier J. Key role of CRF in the skin stress response system. Endocr Rev 2013; 34:827-84. [PMID: 23939821 PMCID: PMC3857130 DOI: 10.1210/er.2012-1092] [Citation(s) in RCA: 282] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 08/02/2013] [Indexed: 02/08/2023]
Abstract
The discovery of corticotropin-releasing factor (CRF) or CRH defining the upper regulatory arm of the hypothalamic-pituitary-adrenal (HPA) axis, along with the identification of the corresponding receptors (CRFRs 1 and 2), represents a milestone in our understanding of central mechanisms regulating body and local homeostasis. We focused on the CRF-led signaling systems in the skin and offer a model for regulation of peripheral homeostasis based on the interaction of CRF and the structurally related urocortins with corresponding receptors and the resulting direct or indirect phenotypic effects that include regulation of epidermal barrier function, skin immune, pigmentary, adnexal, and dermal functions necessary to maintain local and systemic homeostasis. The regulatory modes of action include the classical CRF-led cutaneous equivalent of the central HPA axis, the expression and function of CRF and related peptides, and the stimulation of pro-opiomelanocortin peptides or cytokines. The key regulatory role is assigned to the CRFR-1α receptor, with other isoforms having modulatory effects. CRF can be released from sensory nerves and immune cells in response to emotional and environmental stressors. The expression sequence of peptides includes urocortin/CRF→pro-opiomelanocortin→ACTH, MSH, and β-endorphin. Expression of these peptides and of CRFR-1α is environmentally regulated, and their dysfunction can lead to skin and systemic diseases. Environmentally stressed skin can activate both the central and local HPA axis through either sensory nerves or humoral factors to turn on homeostatic responses counteracting cutaneous and systemic environmental damage. CRF and CRFR-1 may constitute novel targets through the use of specific agonists or antagonists, especially for therapy of skin diseases that worsen with stress, such as atopic dermatitis and psoriasis.
Collapse
Affiliation(s)
- Andrzej T Slominski
- MD, PhD, Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center; 930 Madison Avenue, Suite 500, Memphis, Tennessee 38163.
| | | | | | | | | | | |
Collapse
|
9
|
Stanisz H, Stark A, Kilch T, Schwarz EC, Müller CSL, Peinelt C, Hoth M, Niemeyer BA, Vogt T, Bogeski I. ORAI1 Ca(2+) channels control endothelin-1-induced mitogenesis and melanogenesis in primary human melanocytes. J Invest Dermatol 2012; 132:1443-51. [PMID: 22318387 DOI: 10.1038/jid.2011.478] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
UV radiation of the skin triggers keratinocytes to secrete endothelin-1 (ET-1) that binds to endothelin receptors on neighboring melanocytes. Melanocytes respond with a prolonged increase in intracellular Ca(2+) concentration ([Ca(2+)](i)), which is necessary for proliferation and melanogenesis. A major fraction of the Ca(2+) signal is caused by entry through Ca(2+)-permeable channels of unknown identity in the plasma membrane. ORAI Ca(2+) channels are molecular determinants of Ca(2+) release-activated Ca(2+) (CRAC) channels and are expressed in many tissues. Here, we show that ORAI1-3 and their activating partners stromal interaction molecules 1 and 2 (STIM1 and STIM2) are expressed in human melanocytes. Although ORAI1 is the predominant ORAI isoform, STIM2 mRNA expression exceeds STIM1. Inhibition of ORAI1 by 2-aminoethoxydiphenyl borate (2-APB) or downregulation of ORAI1 by small interfering RNA (siRNA) reduced Ca(2+) entry and CRAC current amplitudes in activated melanocytes. In addition, suppression of ORAI1 caused reduction in the ET-1-induced cellular viability, melanin synthesis, and tyrosinase activity. Our results imply a role for ORAI1 channels in skin pigmentation and their potential involvement in UV-induced stress responses of the human skin.
Collapse
Affiliation(s)
- Hedwig Stanisz
- Department of Dermatology, Venerology and Allergology, University Hospital of the Saarland, Homburg, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Ronan PJ, Summers CH. Molecular Signaling and Translational Significance of the Corticotropin Releasing Factor System. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 98:235-92. [DOI: 10.1016/b978-0-12-385506-0.00006-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
11
|
Kuperman Y, Issler O, Vaughan J, Bilezikjian L, Vale W, Chen A. Expression and regulation of corticotropin-releasing factor receptor type 2β in developing and mature mouse skeletal muscle. Mol Endocrinol 2010; 25:157-69. [PMID: 21084379 DOI: 10.1210/me.2010-0308] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Corticotropin-releasing factor receptor type 2 (CRFR2) is highly expressed in skeletal muscle (SM) tissue where it is suggested to inhibit interactions between insulin signaling pathway components affecting whole-body glucose homeostasis. However, little is known about factors regulating SM CRFR2 expression. Here, we demonstrate the exclusive expression of CRFR2, and not CRFR1, in mature SM tissue using RT-PCR and ribonuclease protection assays and report a differential expression of CRF receptors during C2C12 myogenic differentiation. Whereas C2C12 myoblasts exclusively express CRFR1, the C2C12 myotubes solely express CRFR2. Using cAMP luciferase assays and calcium mobilization measurements, we further demonstrate the functionality of these differentially expressed receptors. Using luciferase reporter assays we show a differential activation of CRFR promoters during myogenic differentiation. Transfections with different fragments of the 5'-flanking region of the mCRFR2β gene fused to a luciferase reporter gene show a promoter-dependent expression of the reporter gene and reveal the importance of the myocyte enhancer factor 2 consensus sequence located at the 3'-proximal region of CRFR2β promoter. Furthermore, we demonstrate that CRFR2 gene transcription in the mature mouse is stimulated by both high-fat diet and chronic variable stress conditions. Performing a whole-genome expression microarray analysis of SM tissues obtained from CRFR2-null mice or wild-type littermates revealed a robust reduction in retinol-binding protein 4 expression levels, an adipokine whose serum levels are elevated in insulin-resistant states. In correlation with the SM CRFR2β levels, the SM retinol-binding protein 4 levels were also elevated in mice subjected to high-fat diet and chronic variable stress conditions. The current findings further position the SM CRFR2 pathways as a relevant physiological system that may affect the known reciprocal relationship between psychological and physiological challenges and the metabolic syndrome.
Collapse
Affiliation(s)
- Yael Kuperman
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | | | | | | | | | | |
Collapse
|
12
|
Kaprara A, Pazaitou-Panayiotou K, Kortsaris A, Chatzaki E. The corticotropin releasing factor system in cancer: expression and pathophysiological implications. Cell Mol Life Sci 2010; 67:1293-306. [PMID: 20143250 PMCID: PMC11115652 DOI: 10.1007/s00018-010-0265-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 12/30/2009] [Accepted: 01/08/2010] [Indexed: 12/15/2022]
Abstract
Malignant tumors express multiple factors that have some role in the regulating networks supporting their ectopic growth. Recently, increased interest has been developing in the expression and biological role of the neuropeptides and receptors of the corticotropin releasing factor (CRF) system, the principal neuroendocrine mediator of the stress response, especially in the light of several R&D programs for small molecule antagonists that could present some anticancer therapeutic benefit. In the present article, we review the literature suggesting that the CRF system could be involved in the regulation of human cancer development. Potential implication in growth, metastasis, angiogenesis, or immune parameters via activation of locally expressed receptors could be clinically exploited by presenting targets of new therapeutic approaches.
Collapse
Affiliation(s)
| | | | - Alexandros Kortsaris
- Laboratory of Biochemistry, Democritus University of Thrace, Alexandroupolis, Thrace Greece
| | - Ekaterini Chatzaki
- Department of Pharmacology, Faculty of Medicine, Democritus University of Thrace, Dragana, 681 00 Alexandroupolis, Greece
| |
Collapse
|
13
|
Kim BJ, Jones HP. Implications of corticotropin releasing factor in targeted anticancer therapy. J Pharm Pract 2010; 23:86-90. [PMID: 21507800 DOI: 10.1177/0897190009360023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
There is a need to develop novel anticancer therapies that eliminate adverse side effects produced by current treatments. Corticotropin releasing factor (CRF), an endogenous neuroedocrine factor, which typically regulates biological and psychological indicators of stress, has recently been found to be expressed by tumor malignancies. Here, we discuss the implications of CRF as a target for antitumor therapy through regulation of tumor immune escape mechanisms.
Collapse
Affiliation(s)
- Byung-Jin Kim
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | | |
Collapse
|
14
|
Gutknecht E, Van der Linden I, Van Kolen K, Verhoeven KFC, Vauquelin G, Dautzenberg FM. Molecular mechanisms of corticotropin-releasing factor receptor-induced calcium signaling. Mol Pharmacol 2008; 75:648-57. [PMID: 19098121 DOI: 10.1124/mol.108.050427] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The molecular mechanisms governing calcium signal transduction of corticotropin-releasing factor (CRF) receptors CRF(1) and CRF(2(a)) stably expressed in human embryonic kidney (HEK) 293 cells were investigated. Calcium signaling strictly depended on intracellular calcium sources, and this is the first study to establish a prominent contribution of the three major G-protein families to CRF receptor-mediated calcium signaling. Overexpression of Galpha(q/11) and Galpha(16) led to leftward shifts of the agonist concentration-response curves. Blockade of Galpha(q/11) proteins by the small interfering RNA (siRNA) technology partially reduced agonist-mediated calcium responses in CRF(1)- and CRF(2(a))-expressing HEK293 cells, thereby proving a contribution of the G(q) protein family. A small but significant inhibition of calcium signaling was recorded by pharmacological inhibition of G(i/o) proteins with pertussis toxin treatment. This effect was mediated by direct binding of Gbetagamma subunits to phospholipase C. G(i/o) inhibition also elevated cAMP responses in CRF receptor-overexpressing HEK293 cells and in Y79 retinoblastoma cells endogenously expressing human CRF(1) and CRF(2(a)) receptors, thereby demonstrating natural coupling of G(i) proteins to both CRF receptors. The strongest reduction of CRF receptor-mediated calcium mobilization was noted when blocking the G(s) signaling protein either by cholera toxin or by siRNA. It is noteworthy that simultaneous inhibition of two G-proteins shed light on the additive effects of G(s) and G(q) on the calcium signaling and, hence, that they act in parallel. On the other hand, G(i) coupling required prior G(s) activation.
Collapse
Affiliation(s)
- Eric Gutknecht
- Johnson and Johnson Research and Development, CNS Research, Beerse, Belgium.
| | | | | | | | | | | |
Collapse
|
15
|
CRF facilitates calcium release from intracellular stores in midbrain dopamine neurons. Neuron 2008; 57:559-70. [PMID: 18304485 DOI: 10.1016/j.neuron.2007.12.029] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 11/20/2007] [Accepted: 12/21/2007] [Indexed: 11/22/2022]
Abstract
Changes in cytosolic calcium are crucial for numerous processes including neuronal plasticity. This study investigates the regulation of cytosolic calcium by corticotropin-releasing factor (CRF) in midbrain dopamine neurons. The results demonstrate that CRF stimulates the release of intracellular calcium from stores through activation of adenylyl cyclase and PKA. Imaging and photolysis experiments showed that the calcium originated from dendrites and required both functional IP3 and ryanodine receptor channels. The elevation in cytosolic calcium potentiated calcium-sensitive potassium channels (sK) activated by action potentials and metabotropic Gq-coupled receptors for glutamate and acetylcholine. This increase in cytosolic calcium activated by postsynaptic Gs-coupled CRF receptors may represent a fundamental mechanism by which stress peptides and hormones can shape Gq-coupled receptor-mediated regulation of neuronal excitability and synaptic plasticity in dopamine neurons.
Collapse
|
16
|
Wang J, Li S. Corticotropin-releasing factor family and its receptors: tumor therapeutic targets? Biochem Biophys Res Commun 2007; 362:785-8. [PMID: 17822675 DOI: 10.1016/j.bbrc.2007.08.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Accepted: 08/03/2007] [Indexed: 12/19/2022]
Abstract
Urocortin (UCN) and corticotropin-releasing factor (CRF) are members of CRF family. Though CRF is mainly distributed in central nervous system (CNS), UCN has been reported to play biologically diverse roles in several systems such as cardiovascular, respiratory, digestive, reproductive, stress, immunologic system, etc. UCN and CRF bind to two known receptors, CRFR1 and CRFR2, to function. Both CRF receptors are distributed in CNS and periphery tissues, and their expression in cancer tissues has been reported. Now there are many documents indicating UCN/CRF play an important role in the regulation of carcinogenesis. There is also evidence indicating UCN/CRF have anticancer effects via CRFRs. This paper will review the effects of CRF family in cancers.
Collapse
Affiliation(s)
- Juejin Wang
- Department of Pharmacology, Nanjing Medical University, Nanjing 210029, PR China
| | | |
Collapse
|
17
|
Fekete ÉM, Zorrilla EP. Physiology, pharmacology, and therapeutic relevance of urocortins in mammals: ancient CRF paralogs. Front Neuroendocrinol 2007; 28:1-27. [PMID: 17083971 PMCID: PMC2730896 DOI: 10.1016/j.yfrne.2006.09.002] [Citation(s) in RCA: 199] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2006] [Revised: 09/05/2006] [Accepted: 09/06/2006] [Indexed: 12/13/2022]
Abstract
Urocortins, three paralogs of the stress-related peptide corticotropin-releasing factor (CRF) found in bony fish, amphibians, birds, and mammals, have unique phylogenies, pharmacologies, and tissue distributions. As a result and despite a structural family resemblance, the natural functions of urocortins and CRF in mammalian homeostatic responses differ substantially. Endogenous urocortins are neither simply counterpoints nor mimics of endogenous CRF action. In their own right, urocortins may be clinically relevant molecules in the pathogenesis or management of many conditions, including congestive heart failure, hypertension, gastrointestinal and inflammatory disorders (irritable bowel syndrome, active gastritis, gastroparesis, and rheumatoid arthritis), atopic/allergic disorders (dermatitis, urticaria, and asthma), pregnancy and parturition (preeclampsia, spontaneous abortion, onset, and maintenance of effective labor), major depression and obesity. Safety trials for intravenous urocortin treatment have already begun for the treatment of congestive heart failure. Further understanding the unique functions of urocortin 1, urocortin 2, and urocortin 3 action may uncover other therapeutic opportunities.
Collapse
Affiliation(s)
- Éva M. Fekete
- Molecular and Integrative Neurosciences Department, The Scripps
Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
- Pécs University Medical School, 7602 Pécs,
Hungary
| | - Eric P. Zorrilla
- Molecular and Integrative Neurosciences Department, The Scripps
Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
- Harold L. Dorris Neurological Research Institute, The Scripps
Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
| |
Collapse
|
18
|
Abstract
Human skin expresses elements of the hypothalamo-pituitary-adrenal (HPA) axis including pro-opiomelanocortin (POMC), corticotropin releasing hormone (CRH), the CRH receptor-1 (CRH-R1), key enzymes of corticosteroid synthesis and synthesizes glucocorticoids. Expression of these elements is organized in functional, cell type-specific regulatory loops, which imitate the signaling hierarchy of the HPA axis. In melanocytes and fibroblasts CRH-induced CRH-R1 stimulation upregulates POMC expression and production of ACTH through activation of cAMP dependent pathway(s). Melanocytes respond with enhanced production of cortisol and corticosterone, which is dependent on POMC activity. Fibroblasts respond to CRH and ACTH with enhanced production of corticosterone, but not cortisol, which is produced constitutively. Organ-cultured human scalp hair follicles also show a fully functional HPA axis equivalent, including cortisol synthesis and secretion and negative feedback regulation by cortisol on CRH expression. Thus, differential, CRH-driven responses of defined cutaneous cell populations reproduce key features of the central HPA axis at the tissue/single cell levels.
Collapse
Affiliation(s)
- Andrzej Slominski
- Department of Pathology and Laboratory Medicine, University of Tennessee, HSC, Memphis, TN 38163, USA.
| | | | | | | |
Collapse
|
19
|
Slominski A, Zbytek B, Zmijewski M, Slominski RM, Kauser S, Wortsman J, Tobin DJ. Corticotropin releasing hormone and the skin. FRONTIERS IN BIOSCIENCE : A JOURNAL AND VIRTUAL LIBRARY 2006; 11:2230-48. [PMID: 16720310 PMCID: PMC1847336 DOI: 10.2741/1966] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cotricotropin-releasing hormone (CRH) and related peptides are produced in skin that is dependent on species and anatomical location. Local peptide production is regulated by ultraviolet radiation (UVR), glucocorticoids and phase of the hair cycle. The skin also expresses the corresponding receptors (CRH-R1 and CRH-R2), with CRH-R1 being the major receptor in humans. CRH-R1 is expressed in epidermal and dermal compartments, and CRH-R2 predominantly in dermal structures. The gene coding for CRH-R1 generates multiple isoforms through a process modulated by UVR, cyclic adenosine monophosphate (cAMP) and phorbol 12-myristate 13-acetate. The phenotypic effects of CRH in human skin cells are largely mediated by CRH-R1alpha through increases in concentrations of cAMP, inositol triphosphate (IP3), or Ca2+ with subsequent activation of protein kinases A (PKA) and C (PKC) dependent pathways. CRH also modulates the activity of nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF-kappaB), activator protein 1 (AP-1) and cAMP responsive element binding protein (CREB). The cellular functions affected by CRH depend on cell type and nutritional status and include modulation of differentiation program(s), proliferation, viability and immune activity. The accumulated evidence indicates that cutaneous CRH is also a component of a local structure organized similarly to the hypothalamo-pituitary-adrenal axis.
Collapse
Affiliation(s)
- Andrzej Slominski
- Department of Pathology, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| | | | | | | | | | | | | |
Collapse
|
20
|
Hauger RL, Risbrough V, Brauns O, Dautzenberg FM. Corticotropin releasing factor (CRF) receptor signaling in the central nervous system: new molecular targets. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2006; 5:453-79. [PMID: 16918397 PMCID: PMC1925123 DOI: 10.2174/187152706777950684] [Citation(s) in RCA: 246] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Corticotropin-releasing factor (CRF) and the related urocortin peptides mediate behavioral, cognitive, autonomic, neuroendocrine and immunologic responses to aversive stimuli by activating CRF(1) or CRF(2) receptors in the central nervous system and anterior pituitary. Markers of hyperactive central CRF systems, including CRF hypersecretion and abnormal hypothalamic-pituitary-adrenal axis functioning, have been identified in subpopulations of patients with anxiety, stress and depressive disorders. Because CRF receptors are rapidly desensitized in the presence of high agonist concentrations, CRF hypersecretion alone may be insufficient to account for the enhanced CRF neurotransmission observed in these patients. Concomitant dysregulation of mechanisms stringently controlling magnitude and duration of CRF receptor signaling also may contribute to this phenomenon. While it is well established that the CRF(1) receptor mediates many anxiety- and depression-like behaviors as well as HPA axis stress responses, CRF(2) receptor functions are not well understood at present. One hypothesis holds that CRF(1) receptor activation initiates fear and anxiety-like responses, while CRF(2) receptor activation re-establishes homeostasis by counteracting the aversive effects of CRF(1) receptor signaling. An alternative hypothesis posits that CRF(1) and CRF(2) receptors contribute to opposite defensive modes, with CRF(1) receptors mediating active defensive responses triggered by escapable stressors, and CRF(2) receptors mediating anxiety- and depression-like responses induced by inescapable, uncontrollable stressors. CRF(1) receptor antagonists are being developed as novel treatments for affective and stress disorders. If it is confirmed that the CRF(2) receptor contributes importantly to anxiety and depression, the development of small molecule CRF(2) receptor antagonists would be therapeutically useful.
Collapse
Affiliation(s)
- Richard L Hauger
- San Diego VA Healthcare System, University of California San Diego, La Jolla, 929093-0603, USA.
| | | | | | | |
Collapse
|
21
|
O'Kane M, Murphy EP, Kirby B. The role of corticotropin-releasing hormone in immune-mediated cutaneous inflammatory disease. Exp Dermatol 2006; 15:143-53. [PMID: 16480421 DOI: 10.1111/j.1600-0625.2006.00382.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Corticotropin-releasing hormone (CRH) coordinates the systemic stress response via hypothalamic-pituitary-adrenal (HPA) axis activation with subsequent modulation of the inflammatory response. Stress is known to affect expression of immune-mediated inflammatory diseases, many of which are associated with HPA axis abnormalities. HPA axis components including CRH and its receptors (CRH-R) exist in the skin and exhibit differential expression according to cell type, physiological fluctuations and disease states. This confirms a local functioning cutaneous HPA-like system. Peripheral CRH may exhibit proinflammatory effects. Animal studies confirm that peripheral CRH is required for induction of the inflammatory response in vivo. CRH and CRH-R are upregulated in inflammatory arthritis synovium and psoriatic skin. CRH may influence mast cell activation, direct modulation of immune cells, angiogenesis and induction of the novel orphan nuclear receptor NURR1. This transcription factor is part of the steroid/thyroid superfamily of related nuclear receptors that includes receptors for steroids, retinoids and vitamin D; ligands of these receptors are effective in treating psoriasis. The roles of CRH and NURR1 in psoriasis and inflammatory skin diseases, especially those associated with stress, remain to be elucidated. This stress may be psychological or physical. CRH, produced locally or delivered by peripheral nerves, may mediate interactions between a cutaneous HPA axis-like system and the central HPA axis--the "brain-skin axis".
Collapse
Affiliation(s)
- Marina O'Kane
- Department of Dermatology, Adelaide and Meath Hospital, Dublin 24, Ireland.
| | | | | |
Collapse
|
22
|
Kauser S, Slominski† A, Wei ET, Tobin DJ. Modulation of the human hair follicle pigmentary unit by corticotropin-releasing hormone and urocortin peptides. FASEB J 2006; 20:882-95. [PMID: 16675846 PMCID: PMC1472637 DOI: 10.1096/fj.05-5257com] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Human skin is a local source of corticotropin-releasing hormone (CRH) and expresses CRH and CRH receptors (CRH-R) at mRNA and protein levels. Epidermal melanocytes respond to CRH by induction of cAMP with up-regulation of pro-opiomelanocortin gene expression and subsequent production of adrenocorticotropin hormone. However, the role of CRH/CRH-R in melanocyte biology is complicated by the significant heterogeneity of cutaneous melanocyte subpopulations, from continuously active and UV-responsive melanocytes in epidermis to UV nonresponsive, hair growth cycle-coupled melanogenesis in hair follicles. In the present study we report that normal human scalp hair follicle melanocytes express CRH at the mRNA level. Furthermore, CRH, urocortin and CRH-R 1 and 2 were differentially expressed in follicular melanocytes, fibroblasts, and keratinocytes depending on anatomic location and differentiation status in situ and in vitro. Stimulation of follicular melanocytes with CRH and CRH peptides, modified for selectivity for CRH-R1 and/or CRH-R2, variably induced cell melanogenesis, dendricity, and proliferation. CRH-peptides also stimulated the expression and activity of Tyrosinase, and expression of Tyrosinase-related protein-1 and-2. However, a modified urocortin peptide highly selective for CRH-R2 down-regulated melanocyte differentiation phenotype. This study indicates that CRH peptides can differentially influence hair follicle melanocyte behavior not only via CRH-R1 signaling but also by complex cross-talk between CRH-R1 and CRH-R2.
Collapse
Affiliation(s)
- Sobia Kauser
- Department of Biomedical Sciences, University of Bradford, West Yorkshire, UK; Department of Pathology and Laboratory Medicine, University of Tennessee HSC, Memphis, Tennessee, USA; and
| | | | - Edward T. Wei
- School of Public Health, University of California, Berkeley, California, USA
| | - Desmond J. Tobin
- Department of Biomedical Sciences, University of Bradford, West Yorkshire, UK; Department of Pathology and Laboratory Medicine, University of Tennessee HSC, Memphis, Tennessee, USA; and
- Correspondence: Department of Biomedical Sciences, University of Bradford, Bradford, West Yorkshire, BD7 1DP, UK. E-mail:
| |
Collapse
|
23
|
Slominski A, Zbytek B, Pisarchik A, Slominski RM, Zmijewski MA, Wortsman J. CRH functions as a growth factor/cytokine in the skin. J Cell Physiol 2006; 206:780-91. [PMID: 16245303 PMCID: PMC1351367 DOI: 10.1002/jcp.20530] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We tested the effect of CRH and related peptides in a large panel of human skin cells for growth factor/cytokine activities. In skin cells CRH action is mediated by CRH-R1, a subject to posttranslational modification with expression of alternatively spliced isoforms. Activation of CRH-R1 induced generation of both cAMP and IP3 in the majority of epidermal and dermal cells (except for normal keratinocytes and one melanoma line), indicating cell type-dependent coupling to signal transduction pathways. Phenotypic effects on cell proliferation were however dependent on both cell type and nutrition conditions. Specifically, CRH stimulated dermal fibroblasts proliferation, by increasing transition from G1/0 to the S phase, while in keratinocytes CRH inhibited cell proliferation. In normal and immortalized melanocytes CRH effect showed dichotomy and thus, it inhibited melanocyte proliferation in serum-containing medium CRH through G2 arrest, while serum free media led instead to CRH enhanced DNA synthesis (through increased transition from G1/G0 to S phase and decreased subG1 signal, indicating DNA degradation). CRH also induced inhibition of early and late apoptosis in the same cells, demonstrated by analysis with the annexin V stains. Thus, CRH acts on epidermal melanocytes as a survival factor under the stress of starvation (anti-apoptotic) as well as inhibitor of growth factors induced cell proliferation. In conclusion, CRH and related peptides can couple CRH-R1 to any of diverse signal transduction pathways; they also regulate cell viability and proliferation in cell type and growth condition-dependent manners.
Collapse
Affiliation(s)
- A Slominski
- Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA.
| | | | | | | | | | | |
Collapse
|
24
|
Cao J, Cetrulo CL, Theoharides TC. Corticotropin-releasing hormone induces vascular endothelial growth factor release from human mast cells via the cAMP/protein kinase A/p38 mitogen-activated protein kinase pathway. Mol Pharmacol 2005; 69:998-1006. [PMID: 16332989 DOI: 10.1124/mol.105.019539] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mast cells are involved in allergic reactions but also in innate immunity and inflammation. Corticotropin-releasing hormone (CRH), the key regulator of the hypothalamic-pituitary-adrenal axis, also has proinflammatory effects, apparently through mast cells. We showed recently that CRH selectively stimulates human leukemic mast cells and human umbilical cord blood-derived mast cells to release newly synthesized vascular endothelial growth factor (VEGF) without release of either preformed mediators or cytokines. This effect was mediated through the activation of CRH receptor-1 and adenylate cyclase with increased intracellular cAMP. However, the precise mechanism by which CRH induces VEGF secretion has not yet been defined. Here, we show that CRH-induced VEGF release was dose-dependently inhibited by the specific protein kinase A inhibitor N-[2-(4-bromocinnamylamino)ethyl]-5-isoquinoline (H89) or the p38 mitogen-activated protein kinase (MAPK) inhibitor 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580) but not by the specific inhibitor 2'-amino-3'-methoxyflavone (PD98059) of mitogen-activated protein kinase kinase, the upstream kinase of the extracellular signal-regulated protein kinase (ERK) or the c-Jun N-terminal kinase (JNK) inhibitor 1,9-pyrazoloanthrone anthra-(1,9-cd)pyrazol-6(2H)-one (SP600125). Furthermore, CRH significantly increased protein kinase A activity, which could be mimicked by the cell-permeable cAMP analog 8-bromo-cAMP, and was blocked by H89 or the adenylate cyclase inhibitor 9-(tetrahydro-2-furanyl)-9H-purine-6-amine (SQ22536). CRH also induced rapid phosphorylation of p38 MAPK, which was mimicked by 8-bromo-cAMP and was inhibited by H89 or SB203580. CRH did not stimulate ERK or JNK phosphorylation and did not increase intracellular calcium levels. These results indicate that CRH induces VEGF release in human mast cells via selective activation of the cAMP/protein kinase A/p38 MAPK signaling pathway, thereby providing further insight into the molecular mechanism of how CRH affects the release of a key proinflammatory mediator.
Collapse
Affiliation(s)
- Jing Cao
- Department of Biochemistry, Tufts University School of Medicine, Boston, MA 02111, USA
| | | | | |
Collapse
|
25
|
Zbytek B, Pikula M, Slominski R, Mysliwski A, Wei E, Wortsman J, Slominski A. Corticotropin-releasing hormone triggers differentiation in HaCaT keratinocytes. Br J Dermatol 2005; 152:474-80. [PMID: 15787816 PMCID: PMC1462964 DOI: 10.1111/j.1365-2133.2005.06217.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Corticotropin-releasing hormone (CRH) is proposed to be involved in the regulation of the proliferative capacity of keratinocytes, based on its significant actions in the skin. These are mediated by CRH-R1alpha and represented by adenylate cyclase activation, Ca2+ influx, inhibition of cell proliferation and modifications in intracellular signal transduction by NF-kappaB. OBJECTIVES To define CRH action in the cell cycle we investigated its effects on the differentiation programme using the HaCaT keratinocytes model. METHODS HaCaT keratinocytes were incubated with CRH in Dulbecco's modified Eagles's medium (containing 1.8 mmol L(-1) calcium) or EpiLife (containing 0.06 mmol L(-1) calcium) medium. Cell proliferation was assessed with the MTT assay. Flow cytometry was used for the measurement of DNA content, cell size and granularity and the expression of cytokeratin 14, cytokeratin 1 and involucrin. The electrophoretic mobility shift assay was used to determine DNA binding activity by AP-1 transcription factor. Expression of cytokeratin 1 was also assessed with immunofluorescence microscopy. RESULTS CRH did produce inhibition of proliferation, which was dose-dependent; the shape of the inhibition curve was determined by the media calcium concentration. CRH action was pinpointed at inhibition of the G0/1 to the S phase transition of the cell cycle. CRH also increased AP-1 binding activity, cell granularity, cytokeratin 1 and involucrin expression, and inhibited cytokeratin 14 expression. CONCLUSIONS These results are consistent with CRH induction of the keratinocyte differentiation programme. Thus, the overall CRH cutaneous actions connote protective functions for the epidermis, that appear to include the triggering or acceleration of the differentiation programme.
Collapse
Affiliation(s)
- B. Zbytek
- Department of Histology and Immunology, Medical University of Gdansk, Gdansk, Poland
- Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, 930 Madison Avenue, RM519, Memphis, TN 38163, U.S.A
| | - M. Pikula
- Department of Histology and Immunology, Medical University of Gdansk, Gdansk, Poland
| | - R.M. Slominski
- Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, 930 Madison Avenue, RM519, Memphis, TN 38163, U.S.A
| | - A. Mysliwski
- Department of Histology and Immunology, Medical University of Gdansk, Gdansk, Poland
| | - E. Wei
- School of Public Health, University of California, Berkeley, CA, U.S.A
| | - J. Wortsman
- Department of Medicine, Southern Illinois University, Springfield, IL, U.S.A
| | - A.T. Slominski
- Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, 930 Madison Avenue, RM519, Memphis, TN 38163, U.S.A
- CorrespondenceAndrzej Slominski. E-mail:
| |
Collapse
|
26
|
Zbytek B, Slominski AT. Corticotropin-releasing hormone induces keratinocyte differentiation in the adult human epidermis. J Cell Physiol 2005; 203:118-26. [PMID: 15468147 DOI: 10.1002/jcp.20209] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Previously we documented that human epidermis exclusively expresses corticotropin releasing hormone receptor 1 (CRH-R1). To define the role of CRH in the epidermis, we investigated its effects on differentiation of normal human adult epidermal keratinocytes. Thus, CRH inhibited proliferation in a dose dependent fashion and significantly decreased Ki-67 antigen expression. This effect was independent of either the presence or the absence of growth factors in the medium. Flow cytometry analysis demonstrated that CRH inhibited the transition from G0/1 to S phase of the cell cycle, which was accompanied by an increased expression of cdk inhibitor p16 (Ink4a) protein. The antiproliferative effect was attenuated by protein kinase C inhibitor (GF109203X) but not by H89 (protein kinase A inhibitor), PD98059, or SB203580 (MAP kinase inhibitors). The cell cycle withdrawal was associated with the induction of keratinocyte differentiation. Thus, CRH stimulated the expression of cytokeratin 1 and involucrin, and inhibited cytokeratin 14 on both mRNA and protein levels. It also increased cell granularity and cell size. Furthermore, CRH induced signal transduction cascade that included stimulation of inositol 1,4,5-triphosphate, which was time and dose dependent. CRH also increased activator protein-1 DNA binding activity with JunD identified as the most important element. Thus, activation of CRH-R1 induces a non-random and sequential signal transduction cascade governing both keratinocyte differentiation and the inhibition of cell proliferation through G0/1 arrest. We propose that this program, triggered by CRH interaction with CRH-R1, includes induction of a transduction pathway involving the sequential activation of phospholipase C, protein kinase C, activator protein-1 (including Jun D), and p16.
Collapse
Affiliation(s)
- Blazej Zbytek
- Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | | |
Collapse
|
27
|
Pisarchik A, Slominski A. Molecular and functional characterization of novel CRFR1 isoforms from the skin. ACTA ACUST UNITED AC 2004; 271:2821-30. [PMID: 15206947 PMCID: PMC1201492 DOI: 10.1111/j.1432-1033.2004.04216.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
In our continued studies on corticotropin releasing factor receptor (CRFR1) signaling in the skin, we tested functional activity of CRFR1alpha, e, f, g and h isoforms after transfection to COS cells. Both membrane-bound and soluble variants are translated in vivo into final protein products that undergo further post-translational modifications. CRFR1alpha was the only isoform coupled directly to adenylate cyclase with the exception of an artificial isoform (CRFR1h2) with the insertion of 37 amino acids between the ligand binding domain and the first extracellular loop that was capable of producing detectable levels of cyclic AMP (cAMP). Soluble isoforms could modulate cell response with CRFR1e attenuating and CRFR1h amplifying CRFR1alpha-coupled cAMP production stimulated by urocortin. Testing with plasmids containing the luciferase reporter gene, and inducible cis-elements (CRE, CaRE, SRE, AP1 or NF-kappaB) demonstrated that only CRFR1alpha was involved directly in the transcriptional regulation, while CRFR1g inhibited CRE activity. Significantly higher reporter gene expression by CRF was observed than that mediated by 4beta-phorbol 12-myristate 13-acetate and forskolin alone, being compatible with the concomitant treatment by phorbol 12-myristate 13-acetate and forskolin. This suggests that both protein kinase A and C can be involved in CRF-dependent signal transduction.
Collapse
Affiliation(s)
| | - Andrzej Slominski
- Correspondence to A.T. Slominski, Department of Pathology and Laboratory Medicine, 930 Madison Avenue, Room 519, Memphis, TN 38163, USA. Fax: +1 901 4486979, Tel.: +1 901 4483741, E-mail:
| |
Collapse
|
28
|
Wiesner B, Roloff B, Fechner K, Slominski A. Intracellular calcium measurements of single human skin cells after stimulation with corticotropin-releasing factor and urocortin using confocal laser scanning microscopy. J Cell Sci 2003; 116:1261-8. [PMID: 12615968 DOI: 10.1242/jcs.00301] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Using confocal laser scanning microscopy we investigated the Ca(2+) distribution in single corticotropin releasing factor- and urocortin-stimulated human skin cells. The models tested included melanoma cells, neonatal melanocytes and keratinocytes, and immortalized HaCaT keratinocytes. The changes in intracellular Ca(2+) signal intensities observed after stimulation of different cell types with corticotropin releasing factor and urocortin showed that: (1) the increase of intracellular Ca(2+) concentration was caused by a Ca(2+) influx (inhibition by EGTA); (2) this Ca(2+) influx took place through voltage-activated Ca(2+) ion channels (inhibition by d-cis-diltiazem, verapamil) and (3) cyclic nucleotide-gated ion channels were not involved in this process (no effect of Mg(2+)). The effects were also observed at very low peptide concentrations (10(-13) M) with no apparent linear correlation between peptide dosage and increase of fluorescence intensity, which implied co-expression of different corticotropin releasing factor receptor forms in the same cell. Immortalized (HaCaT) keratinocytes exhibited the strongest differential increases of a Ca(2+) fluorescence after peptide-stimulation. Corticotropin releasing factor induced Ca(2+) flux into the cytoplasm, while urocortin Ca(2+) flux into the nucleus with a remarkable oscillatory effect. The latter indicated the presence of an intracellular urocortin-induced signal transduction pathway that is unique to keratinocytes.
Collapse
|
29
|
Kozicz T, Arimura A, Maderdrut JL, Lázár G. Distribution of urocortin-like immunoreactivity in the central nervous system of the frog Rana esculenta. J Comp Neurol 2002; 453:185-98. [PMID: 12373783 DOI: 10.1002/cne.10403] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Corticotropin-releasing factor (CRF), sauvagine, and urotensin I are all members of the so-called CRF neuropeptide family. Urocortin (Ucn), a 40-amino-acid neuropeptide recently isolated from the rat brain, is the newest member of this family. Until now, the distribution of Ucn in the central nervous system (CNS) has been studied only in placental mammals. We used a polyclonal antiserum against rat Ucn to determine the distribution of Ucn-like immunoreactivity in the CNS of the green frog, Rana esculenta. The great majority of Ucn-immunoreactive perikarya was seen in the anterior preoptic area, ventromedial thalamic nucleus, posterior tuberculum, nucleus of the medial longitudinal fasciculus, and Edinger-Westphal nucleus. Urocortin-immunoreactive nerve cells were also observed in the motor nuclei of the trigeminal and facial nerves and in the hypoglossal nucleus. Immunoreactive fibers were found in the medial and lateral septal nuclei, bed nucleus of the stria terminalis, many of the thalamic and hypothalamic nuclei, mesencephalic tectum, tegmental nuclei, torus semicircularis, and dorsal horn and central field of the spinal cord. Only scattered Ucn-immunoreactive axon terminals were observed in the external zone of the medial eminence. The densest accumulations of Ucn-immunoreactive nerve terminals were seen in the granular layer of the cerebellum and cochlear nuclei. Our results suggest that an ortholog of mammalian Ucn occurs in the CNS of the green frog. The distribution of Ucn-like immunoreactivity in Rana esculenta showed many similarities to the distribution in placental mammals. The distribution of Ucn-like immunoreactivity in the anuran CNS was different from that of CRF and sauvagine, so our results suggest that at least three different lineages of the CRF neuropeptide family occur in the anuran CNS.
Collapse
Affiliation(s)
- Tamás Kozicz
- Department of Human Anatomy, University of Pécs Medical Faculty, Pécs, H-7624 Hungary.
| | | | | | | |
Collapse
|
30
|
Abstract
Abnormal signaling at corticotropin-releasing factor CRF1 and CRF2 receptors might contribute to the pathophysiology of stress-related disorders such as anxiety, depression and eating disorders, in addition to cardiac and inflammatory disorders. Recently, molecular characterization of CRF1 and CRF2 receptors and the cloning of novel ligands--urocortin, stresscopin-related peptide/urocortin II, and stresscopin/urocortin III--have revealed a far-reaching physiological importance for the family of CRF peptides. Although the physiological roles of the CRF2 receptor remain to be defined, the preclinical and clinical development of specific small-molecule antagonists of the CRF1 receptor opens new avenues for the treatment of psychiatric and neurological disorders.
Collapse
Affiliation(s)
- Frank M Dautzenberg
- Therapeutic Applications, Axovan, Innovation Center, Gewerbestrasse 16, 4123, Allschwil, Switzerland.
| | | |
Collapse
|
31
|
Slominski A, Wortsman J, Pisarchik A, Zbytek B, Linton EA, Mazurkiewicz JE, Wei ET. Cutaneous expression of corticotropin-releasing hormone (CRH), urocortin, and CRH receptors. FASEB J 2001; 15:1678-93. [PMID: 11481215 DOI: 10.1096/fj.00-0850rev] [Citation(s) in RCA: 234] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Studies in mammalian skin have shown expression of the genes for corticotropin-releasing hormone (CRH) and the related urocortin peptide, with subsequent production of the respective peptides. Recent molecular and biochemical analyses have further revealed the presence of CRH receptors (CRH-Rs). These CRH-Rs are functional, responding to CRH and urocortin peptides (exogenous or produced locally) through activation of receptor(s)-mediated pathways to modify skin cell phenotype. Thus, when taken together with the previous findings of cutaneous expression of POMC and its receptors, these observations extend the range of regulatory elements of the hypothalamic-pituitary-adrenal axis expressed in mammalian skin. Overall, the cutaneous CRH/POMC expression is highly reactive to common stressors such as immune cytokines, ultraviolet radiation, cutaneous pathology, or even the physiological changes associated with the hair cycle phase. Therefore, similar to its central analog, the local expression and action of CRH/POMC elements appear to be highly organized and entrained, representing general mechanism of cutaneous response to stressful stimuli. In such a CRH/POMC system, the CRH-Rs may be a central element.
Collapse
Affiliation(s)
- A Slominski
- Department of Pathology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA.
| | | | | | | | | | | | | |
Collapse
|
32
|
Quevedo ME, Slominski A, Pinto W, Wei E, Wortsman J. Pleiotropic effects of corticotropin releasing hormone on normal human skin keratinocytes. In Vitro Cell Dev Biol Anim 2001; 37:50-4. [PMID: 11249206 DOI: 10.1290/1071-2690(2001)037<0050:peocrh>2.0.co;2] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis is the major stress response system. Several components of the HPA axis, such as corticotropin-releasing hormone (CRH) and POMC peptides and their receptors are also present in the skin. In earlier studies, we showed that CRH inhibits cellular proliferation of immortalized human keratinocytes. We now examine further the functional activity of the HPA axis in the skin, by characterizing the actions of CRH on normal foreskin keratinocytes. The CRH receptor was detected as CRH-R1 antigen at 47 kDa in the cultured keratinocytes by Western blotting, and immunohistochemistry demonstrated its presence in the epidermal and follicular keratinocytes. CRH is also biologically active in cultured keratinocytes, where it inhibits proliferation and enhances the interferon-gamma-stimulated expression of the hCAM and ICAM-1 adhesion molecules and of the HLA-DR antigen. These effects were concentration-dependent, with maximal activity at CRH 10(-7) M. Thus, in the keratinocyte, the most important cellular component of the epidermis, CRH appears to induce a shift in energy metabolism away from proliferation activity, and toward the enhancement of immunoactivity. Therefore, similar to its central actions, cutaneous CRH may also he involved in the stress response, but at a highly localized level.
Collapse
Affiliation(s)
- M E Quevedo
- Department of Pathology, Loyola University Medical Center, Maywood, Illinois 60153, USA
| | | | | | | | | |
Collapse
|
33
|
Abstract
The classical observations of the skin as a target for melanotropins have been complemented by the discovery of their actual production at the local level. In fact, all of the elements controlling the activity of the hypothalamus-pituitary-adrenal axis are expressed in the skin including CRH, urocortin, and POMC, with its products ACTH, alpha-MSH, and beta-endorphin. Demonstration of the corresponding receptors in the same cells suggests para- or autocrine mechanisms of action. These findings, together with the demonstration of cutaneous production of numerous other hormones including vitamin D3, PTH-related protein (PTHrP), catecholamines, and acetylcholine that share regulation by environmental stressors such as UV light, underlie a role for these agents in the skin response to stress. The endocrine mediators with their receptors are organized into dermal and epidermal units that allow precise control of their activity in a field-restricted manner. The skin neuroendocrine system communicates with itself and with the systemic level through humoral and neural pathways to induce vascular, immune, or pigmentary changes, to directly buffer noxious agents or neutralize the elicited local reactions. Therefore, we suggest that the skin neuroendocrine system acts by preserving and maintaining the skin structural and functional integrity and, by inference, systemic homeostasis.
Collapse
Affiliation(s)
- A Slominski
- Department of Pathology ,University of Tennessee, Memphis 38163, USA.
| | | |
Collapse
|
34
|
Slominski A, Wortsman J, Luger T, Paus R, Solomon S. Corticotropin releasing hormone and proopiomelanocortin involvement in the cutaneous response to stress. Physiol Rev 2000; 80:979-1020. [PMID: 10893429 DOI: 10.1152/physrev.2000.80.3.979] [Citation(s) in RCA: 559] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The skin is a known target organ for the proopiomelanocortin (POMC)-derived neuropeptides alpha-melanocyte stimulating hormone (alpha-MSH), beta-endorphin, and ACTH and also a source of these peptides. Skin expression levels of the POMC gene and POMC/corticotropin releasing hormone (CRH) peptides are not static but are determined by such factors as the physiological changes associated with hair cycle (highest in anagen phase), ultraviolet radiation (UVR) exposure, immune cytokine release, or the presence of cutaneous pathology. Among the cytokines, the proinflammatory interleukin-1 produces important upregulation of cutaneous levels of POMC mRNA, POMC peptides, and MSH receptors; UVR also stimulates expression of all the components of the CRH/POMC system including expression of the corresponding receptors. Molecular characterization of the cutaneous POMC gene shows mRNA forms similar to those found in the pituitary, which are expressed together with shorter variants. The receptors for POMC peptides expressed in the skin are functional and include MC1, MC5 and mu-opiate, although most predominant are those of the MC1 class recognizing MSH and ACTH. Receptors for CRH are also present in the skin. Because expression of, for example, the MC1 receptor is stimulated in a similar dose-dependent manner by UVR, cytokines, MSH peptides or melanin precursors, actions of the ligand peptides represent a stochastic (predictable) nonspecific response to environmental/endogenous stresses. The powerful effects of POMC peptides and probably CRH on the skin pigmentary, immune, and adnexal systems are consistent with stress-neutralizing activity addressed at maintaining skin integrity to restrict disruptions of internal homeostasis. Hence, cutaneous expression of the CRH/POMC system is highly organized, encoding mediators and receptors similar to the hypothalamic-pituitary-adrenal (HPA) axis. This CRH/POMC skin system appears to generate a function analogous to the HPA axis, that in the skin is expressed as a highly localized response which neutralizes noxious stimuli and attendant immune reactions.
Collapse
Affiliation(s)
- A Slominski
- Department of Pathology, Loyola University Medical Center, Maywood, Illinois, USA
| | | | | | | | | |
Collapse
|
35
|
Veraksits A, Bileviciute-Ljungar I, Maaroos J, Vasar E, Lundeberg T. Neuronal mechanisms contribute to corticotropin-releasing factor-induced anti-oedema effect in the rat hind paw. Neuropeptides 2000; 34:129-34. [PMID: 10985930 DOI: 10.1054/npep.2000.0800] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The present study is designed to elucidate the involvement of neuronal mechanisms in corticotropin-releasing factor (CRF)-induced anti-oedema effects. Oedema was induced in the rat hind paw by subcutaneous injection of 3 nmol of serotonin (5-HT). A single dose of CRF (9.4, 37.5 or 75 pmol) was given either ipsilaterally or contralaterally 30 min before 5-HT injection and oedema formation was subsequently measured every 30 min for 5.5 h. Compared to saline pre-treatment CRF (37.5 pmol) reduced oedema formation for 3.5 h when given ipsilaterally, and at 1.5 h (9.33, 37.5 and 75 pmol) when injected contralaterally. Administration of CRF along with CRF receptor antagonist, alpha-helical CRF, abolished the anti-oedema effects of CRF. Sciatic nerve ligation on the injected side attenuated the ipsilateral CRF-induced anti-oedema effect when compared with saline pre-treatment and sham-operated rats. Ipsilateral pre-treatment with 37.5 pmol of CRF caused a reduction in hind paw temperature compared to treatment with saline. Results of the present study indicate that the nervous system contributes to CRF effects in 5-HT-induced oedema formation.
Collapse
Affiliation(s)
- A Veraksits
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
| | | | | | | | | |
Collapse
|
36
|
Abstract
The neuropeptide corticotropin-releasing factor (CRE) and related neuropeptides not only mediate hormonal responses to stressors but also have a neurotropic role in the central nervous system to mediate behavioral responses to stressors. CRF antagonists effectively block CRF responses and have effects opposite those of CRF in many stress-related situations. Recent advances suggest that in addition to CRF itself there is another CRF-related neuropeptide, urocortin, that may be involved in stress-related responses, particularly those involving appetite. At least two CRF receptors have been discovered to date, CRF-1 and CRF-2. CRF may be involved in various aspects of the addiction cycle associated with drugs of abuse. CRF appears to be activated during stress-induced reinstatement of drug taking as well as acute withdrawal from all major drugs of abuse. CRF is hypothesized to be part of an allostatic change leading to vulnerability to relapse during prolonged abstinence from drugs of abuse.
Collapse
Affiliation(s)
- G F Koob
- Department of Neuropharmacology, Scripps Research Institute, La Jolla, California 92037, USA.
| |
Collapse
|
37
|
Slominski AT, Roloff B, Zbytek B, Wei ET, Fechner K, Curry J, Wortsman J. Corticotropin releasing hormone and related peptides can act as bioregulatory factors in human keratinocytes. In Vitro Cell Dev Biol Anim 2000; 36:211-6. [PMID: 10777063 DOI: 10.1290/1071-2690(2000)036<0211:crharp>2.0.co;2] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Following previous findings in human skin of the functional expression of genes for the corticotropin releasing hormone (CRH) receptor type 1 (CRH-R1) and CRH itself, we searched for local phenotypic effects for peptides related to CRH. We now report that CRH, sauvagine, and urocortin inhibit proliferation of human HaCaT keratinocytes in a dose-dependent manner. The peptides produced variable cyclic adenosine 3':5'-monophosphate stimulation, with CRH having the highest potency. Binding of iodine 125 CRH to intact keratinocytes was inhibited by increasing doses of CRH, sauvagine, or urocortin, all showing equal inhibitory potency. Immunocytochemistry identified CRH-R1 immunoreactivity in HaCaT keratinocytes. In conclusion, CRH (exogenous or produced locally) and the related urocortin and sauvagine peptides can modify human keratinocyte phenotype through a receptor-mediated pathway.
Collapse
Affiliation(s)
- A T Slominski
- Department of Pathology, Medical Center, Loyola University, Maywood, Illinois 60153, USA.
| | | | | | | | | | | | | |
Collapse
|
38
|
Koob GF, Heinrichs SC. A role for corticotropin releasing factor and urocortin in behavioral responses to stressors. Brain Res 1999; 848:141-52. [PMID: 10612706 DOI: 10.1016/s0006-8993(99)01991-5] [Citation(s) in RCA: 409] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Corticotropin-releasing factor (CRF) and CRF-related neuropeptides have an important role in the central nervous system to mediate behavioral responses to stressors. CRF receptor antagonists are very effective in reversing stress-induced suppression and activation in behavior. An additional CRF-like neuropeptide, urocortin, has been identified in the brain and has a high affinity for the CRF-2 receptor in addition to the CRF-1 receptor. Urocortin has many of the effects of CRF but also is significantly more potent than CRF in decreasing feeding in both meal-deprived and free-feeding rats. In mouse genetic models, mice over-expressing CRF show anxiogenic-like responses compared to wild-type mice, and mice lacking the CRF-1 receptor showed an anxiolytic-like behavioral profile compared to wild-type mice. Results to date have led to the hypothesis that CRF-1 receptors may mediate CRF-like neuropeptide effects on behavioral responses to stressors, but CRF-2 receptors may mediate the suppression of feeding produced by CRF-like neuropeptides. Brain sites for the behavioral effects of CRF include the locus coeruleus (LC), paraventricular nucleus (PVN) of the hypothalamus, the bed nucleus of the stria terminalis (BNST), and the central nucleus of the amygdala. CRF may also be activated during acute withdrawal from all major drugs of abuse, and recent data suggest that CRF may contribute to the dependence and vulnerability to relapse associated with chronic administration of drugs of abuse. These data suggest that CRF systems in the brain have a unique role in mediating behavioral responses to diverse stressors. These systems may be particularly important in situations were an organism must mobilize not only the pituitary adrenal system, but also the central nervous system in response to environmental challenge. Clearly, dysfunction in such a fundamental brain-activating system may be the key to a variety of pathophysiological conditions involving abnormal responses to stressors such as anxiety disorders, affective disorders, and anorexia nervosa.
Collapse
Affiliation(s)
- G F Koob
- Department of Neuropharmacology, CVN-7, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | | |
Collapse
|
39
|
Arbiser JL, Karalis K, Viswanathan A, Koike C, Anand-Apte B, Flynn E, Zetter B, Majzoub JA. Corticotropin-releasing hormone stimulates angiogenesis and epithelial tumor growth in the skin. J Invest Dermatol 1999; 113:838-42. [PMID: 10571742 DOI: 10.1046/j.1523-1747.1999.00760.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The hypothalamic neuropeptide corticotropin-releasing hormone is the major hypothalamic regulator of the endocrine pituitary-adrenal axis. Corticotropin-releasing hormone is also expressed in many peripheral sites, where its functions are unclear. It is also secreted by diverse neoplasms, where it may be associated with malignant behavior. To provide information regarding the function of corticotropin-releasing hormone in peripheral sites and in tumors, we asked whether corticotropin-releasing hormone has angiogenic properties. In vitro, we found that human corticotropin-releasing hormone specifically stimulates endothelial chemotaxis via a corticotropin-releasing hormone receptor-dependent mechanism. In vivo, subcutaneous inoculation of nude mice with human epithelial tumor cells engineered to secrete corticotropin-releasing hormone was associated with significantly enhanced angiogenesis (2.3-fold over control) and tumor growth (5-fold over control). Peripheral corticotropin-releasing hormone may thus enhance local angiogenesis, which may provide clues to its function outside of the nervous system.
Collapse
Affiliation(s)
- J L Arbiser
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Abstract
Corticotropin-releasing factor (CRF) and related peptides in the central nervous system appears to have activating properties on behavior and to enhance behavioral responses to stressors. CRF and urocortin injected into the brain produces increases in arousal as measured by locomotor activation and increased responsiveness to stressful stimuli. These effects of CRF appear to be independent of the pituitary adrenal axis and can be reversed by specific and selective CRF antagonists alpha-helical CRF9-41 and D-Phe CRF12-41. Perhaps more importantly, CRF antagonists can reverse behavioral responses to many stressors. These results suggest that endogenous CRF systems in the brain may have a role in mediating behavioral responses to stressors. Norepinephrine systems emanating from the nucleus locus coeruleus also long have been hypothesized to be involved in mediating behavioral constructs associated with alertness, arousal, and stress. Pharmacologic, physiologic, and neuroanatomic evidence supports an important role for a CRF-norepinephrine interaction in the region of the locus coeruleus in response to stressors that may be modality-specific where CRF neurons activate the locus coeruleus. One may hypothesize that another norepinephrine-CRF interaction may occur in the terminal projections of the forebrain norepinephrine systems in the paraventricular nucleus of the hypothalamus, the bed nucleus of the stria terminalis, and the central nucleus of the amygdala where norepinephrine stimulates CRF release. Such a feed-forward system may be particularly important in situations where an organism must mobilize not only the pituitary adrenal system but also the central nervous system, in response to environmental challenge. However, such a feed-forward mechanism in a fundamental brain-activating system may be particularly vulnerable to dysfunction and thus, may be the key to a variety of pathophysiologic conditions involving abnormal responses to stressors such as anorexia nervosa, anxiety, and affective disorders.
Collapse
Affiliation(s)
- G F Koob
- Department of Neuropharmacology, Scripps Research Institute, La Jolla, CA 92037, USA
| |
Collapse
|
41
|
Slominski AT, Botchkarev V, Choudhry M, Fazal N, Fechner K, Furkert J, Krause E, Roloff B, Sayeed M, Wei E, Zbytek B, Zipper J, Wortsman J, Paus R. Cutaneous expression of CRH and CRH-R. Is there a "skin stress response system?". Ann N Y Acad Sci 1999; 885:287-311. [PMID: 10816662 DOI: 10.1111/j.1749-6632.1999.tb08686.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The classical neuroendocrine pathway for response to systemic stress is by hypothalamic release of corticotropin releasing hormone (CRH), subsequent activation of pituitary CRH receptors (CRH-R), and production and release of proopiomelanocortin (POMC) derived peptides. It has been proposed that an equivalent to the hypothalamic-pituitary-adrenal axis functions in mammalian skin, in response to local stress (see Reference 1). To further define such system we used immunocytochemistry, RP-HPLC separation, and RIA techniques, in rodent and human skin, and in cultured normal and malignant melanocytes and keratinocytes. Production of mRNA for CRH-R1 was documented in mouse and human skin using RT-PCR and Northern blot techniques; CRH binding sites and CRH-R1 protein were also identified. Addition of CRH to immortalized human keratinocytes, and to rodent and human melanoma cells induced rapid, specific, and dose-dependent increases in intracellular Ca2+. The latter were inhibited by the CRH antagonist alpha-helical-CRH(9-41) and by the depletion of extracellular calcium with EGTA. CRH production was enhanced by ultraviolet light radiation and forskolin (a stimulator for intracellular cAMP production), and inhibited by dexamethasone. Thus, evidence that skin cells, both produce CRH and express functional CRH-R1, supports the existence of a local CRH/CRH-R neuroendocrine pathway that may be activated within the context of a skin stress response system.
Collapse
Affiliation(s)
- A T Slominski
- Department of Pathology, Loyola University, Maywood, Illinois, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|