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Houari S, Loiodice S, Jedeon K, Berdal A, Babajko S. Expression of Steroid Receptors in Ameloblasts during Amelogenesis in Rat Incisors. Front Physiol 2016; 7:503. [PMID: 27853434 PMCID: PMC5090168 DOI: 10.3389/fphys.2016.00503] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 10/13/2016] [Indexed: 12/02/2022] Open
Abstract
Endocrine disrupting chemicals (EDCs) play a part in the modern burst of diseases and interfere with the steroid hormone axis. Bisphenol A (BPA), one of the most active and widely used EDCs, affects ameloblast functions, leading to an enamel hypomineralization pattern similar to that of Molar Incisor Hypomineralization (MIH). In order to explore the molecular pathways stimulated by BPA during amelogenesis, we thoroughly investigated the receptors known to directly or indirectly mediate the effects of BPA. The expression patterns of high affinity BPA receptors (ERRγ, GPR30), of ketosteroid receptors (ERs, AR, PGR, GR, MR), of the retinoid receptor RXRα, and PPARγ were established using RT-qPCR analysis of RNAs extracted from microdissected enamel organ of adult rats. Their expression was dependent on the stage of ameloblast differentiation, except that of ERβ and PPARγ which remained undetectable. An additional large scale microarray analysis revealed three main groups of receptors according to their level of expression in maturation-stage ameloblasts. The expression level of RXRα was the highest, similar to the vitamin D receptor (VDR), whereas the others were 13 to 612-fold lower, with AR and GR being intermediate. Immunofluorescent analysis of VDR, ERα and AR confirmed their presence mainly in maturation- stage ameloblasts. These data provide further evidence that ameloblasts express a specific combination of hormonal receptors depending on their developmental stage. This study represents the first step toward understanding dental endocrinology as well as some of the effects of EDCs on the pathophysiology of amelogenesis.
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Affiliation(s)
- Sophia Houari
- Paris Laboratory of Molecular Oral Pathophysiology, Centre de Recherche des Cordeliers, Institut National de la Santé et de la Recherche Médicale UMRS 1138, Université Paris-Descartes, Université Pierre et Marie Curie-ParisParis, France; Université Paris-Diderot, Unité de Formation et de Recherche d'OdontologieParis, France
| | - Sophia Loiodice
- Paris Laboratory of Molecular Oral Pathophysiology, Centre de Recherche des Cordeliers, Institut National de la Santé et de la Recherche Médicale UMRS 1138, Université Paris-Descartes, Université Pierre et Marie Curie-ParisParis, France; Université Paris-Diderot, Unité de Formation et de Recherche d'OdontologieParis, France
| | - Katia Jedeon
- Paris Laboratory of Molecular Oral Pathophysiology, Centre de Recherche des Cordeliers, Institut National de la Santé et de la Recherche Médicale UMRS 1138, Université Paris-Descartes, Université Pierre et Marie Curie-ParisParis, France; Université Paris-Diderot, Unité de Formation et de Recherche d'OdontologieParis, France
| | - Ariane Berdal
- Paris Laboratory of Molecular Oral Pathophysiology, Centre de Recherche des Cordeliers, Institut National de la Santé et de la Recherche Médicale UMRS 1138, Université Paris-Descartes, Université Pierre et Marie Curie-ParisParis, France; Université Paris-Diderot, Unité de Formation et de Recherche d'OdontologieParis, France; Centre de Référence des maladies rares de la face et de la cavité buccale MAFACE hôpital Rothschild, AP-HPParis, France
| | - Sylvie Babajko
- Paris Laboratory of Molecular Oral Pathophysiology, Centre de Recherche des Cordeliers, Institut National de la Santé et de la Recherche Médicale UMRS 1138, Université Paris-Descartes, Université Pierre et Marie Curie-ParisParis, France; Université Paris-Diderot, Unité de Formation et de Recherche d'OdontologieParis, France
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Laugel-Haushalter V, Paschaki M, Marangoni P, Pilgram C, Langer A, Kuntz T, Demassue J, Morkmued S, Choquet P, Constantinesco A, Bornert F, Schmittbuhl M, Pannetier S, Viriot L, Hanauer A, Dollé P, Bloch-Zupan A. RSK2 is a modulator of craniofacial development. PLoS One 2014; 9:e84343. [PMID: 24416220 PMCID: PMC3885557 DOI: 10.1371/journal.pone.0084343] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 11/21/2013] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND The RSK2 gene is responsible for Coffin-Lowry syndrome, an X-linked dominant genetic disorder causing mental retardation, skeletal growth delays, with craniofacial and digital abnormalities typically associated with this syndrome. Craniofacial and dental anomalies encountered in this rare disease have been poorly characterized. METHODOLOGY/PRINCIPAL FINDINGS We examined, using X-Ray microtomographic analysis, the variable craniofacial dysmorphism and dental anomalies present in Rsk2 knockout mice, a model of Coffin-Lowry syndrome, as well as in triple Rsk1,2,3 knockout mutants. We report Rsk mutation produces surpernumerary teeth midline/mesial to the first molar. This highly penetrant phenotype recapitulates more ancestral tooth structures lost with evolution. Most likely this leads to a reduction of the maxillary diastema. Abnormalities of molar shape were generally restricted to the mesial part of both upper and lower first molars (M1). Expression analysis of the four Rsk genes (Rsk1, 2, 3 and 4) was performed at various stages of odontogenesis in wild-type (WT) mice. Rsk2 is expressed in the mesenchymal, neural crest-derived compartment, correlating with proliferative areas of the developing teeth. This is consistent with RSK2 functioning in cell cycle control and growth regulation, functions potentially responsible for severe dental phenotypes. To uncover molecular pathways involved in the etiology of these defects, we performed a comparative transcriptomic (DNA microarray) analysis of mandibular wild-type versus Rsk2-/Y molars. We further demonstrated a misregulation of several critical genes, using a Rsk2 shRNA knock-down strategy in molar tooth germs cultured in vitro. CONCLUSIONS This study reveals RSK2 regulates craniofacial development including tooth development and patterning via novel transcriptional targets.
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Affiliation(s)
- Virginie Laugel-Haushalter
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Centre National de la Recherche Scientifique (UMR 7104), Institut National de la Santé et de la Recherche Médicale (U 964), University of Strasbourg, Illkirch, France
| | - Marie Paschaki
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Centre National de la Recherche Scientifique (UMR 7104), Institut National de la Santé et de la Recherche Médicale (U 964), University of Strasbourg, Illkirch, France
| | - Pauline Marangoni
- Team «Evo-Devo of Vertebrate Dentition», Institut de Génomique Fonctionnelle de Lyon, Unité Mixte de Recherche 5242 Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon, Claude Bernard Lyon 1 University, Lyon, France
| | - Coralie Pilgram
- Faculty of Dentistry, University of Strasbourg, Strasbourg France
| | - Arnaud Langer
- Faculty of Dentistry, University of Strasbourg, Strasbourg France
| | - Thibaut Kuntz
- Faculty of Dentistry, University of Strasbourg, Strasbourg France
| | - Julie Demassue
- Faculty of Dentistry, University of Strasbourg, Strasbourg France
| | - Supawich Morkmued
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Centre National de la Recherche Scientifique (UMR 7104), Institut National de la Santé et de la Recherche Médicale (U 964), University of Strasbourg, Illkirch, France
- Faculty of Dentistry, University of Strasbourg, Strasbourg France
- Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand
| | - Philippe Choquet
- UF6237 Preclinical Imaging Lab, Biophysics and Nuclear Medicine, Hôpitaux Universitaires de Strasbourg (HUS), Strasbourg, France; ICube, CNRS, University of Strasbourg, Strasbourg, France
| | - André Constantinesco
- UF6237 Preclinical Imaging Lab, Biophysics and Nuclear Medicine, Hôpitaux Universitaires de Strasbourg (HUS), Strasbourg, France; ICube, CNRS, University of Strasbourg, Strasbourg, France
| | - Fabien Bornert
- Faculty of Dentistry, University of Strasbourg, Strasbourg France
- INSERM U1121, "Biomaterials and Bioengineering", University of Strasbourg, Strasbourg, France
| | - Matthieu Schmittbuhl
- Faculty of Dentistry, University of Strasbourg, Strasbourg France
- Reference Centre for Orodental Manifestations of Rare Diseases, Pôle de Médecine et Chirurgie Bucco-dentaires, Hôpitaux Universitaires de Strasbourg (HUS), Strasbourg, France
- INSERM U1121, "Biomaterials and Bioengineering", University of Strasbourg, Strasbourg, France
| | - Solange Pannetier
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Centre National de la Recherche Scientifique (UMR 7104), Institut National de la Santé et de la Recherche Médicale (U 964), University of Strasbourg, Illkirch, France
| | - Laurent Viriot
- Team «Evo-Devo of Vertebrate Dentition», Institut de Génomique Fonctionnelle de Lyon, Unité Mixte de Recherche 5242 Centre National de la Recherche Scientifique, Ecole Normale Supérieure de Lyon, Claude Bernard Lyon 1 University, Lyon, France
| | - André Hanauer
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Centre National de la Recherche Scientifique (UMR 7104), Institut National de la Santé et de la Recherche Médicale (U 964), University of Strasbourg, Illkirch, France
| | - Pascal Dollé
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Centre National de la Recherche Scientifique (UMR 7104), Institut National de la Santé et de la Recherche Médicale (U 964), University of Strasbourg, Illkirch, France
| | - Agnès Bloch-Zupan
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Centre National de la Recherche Scientifique (UMR 7104), Institut National de la Santé et de la Recherche Médicale (U 964), University of Strasbourg, Illkirch, France
- Faculty of Dentistry, University of Strasbourg, Strasbourg France
- Reference Centre for Orodental Manifestations of Rare Diseases, Pôle de Médecine et Chirurgie Bucco-dentaires, Hôpitaux Universitaires de Strasbourg (HUS), Strasbourg, France
- * E-mail:
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Laugel-Haushalter V, Paschaki M, Thibault-Carpentier C, Dembelé D, Dollé P, Bloch-Zupan A. Molars and incisors: show your microarray IDs. BMC Res Notes 2013; 6:113. [PMID: 23531410 PMCID: PMC3658942 DOI: 10.1186/1756-0500-6-113] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 03/08/2013] [Indexed: 01/31/2023] Open
Abstract
Background One of the key questions in developmental biology is how, from a relatively small number of conserved signaling pathways, is it possible to generate organs displaying a wide range of shapes, tissue organization, and function. The dentition and its distinct specific tooth types represent a valuable system to address the issues of differential molecular signatures. To identify such signatures, we performed a comparative transcriptomic analysis of developing murine lower incisors, mandibular molars and maxillary molars at the developmental cap stage (E14.5). Results 231 genes were identified as being differentially expressed between mandibular incisors and molars, with a fold change higher than 2 and a false discovery rate lower than 0.1, whereas only 96 genes were discovered as being differentially expressed between mandibular and maxillary molars. Numerous genes belonging to specific signaling pathways (the Hedgehog, Notch, Wnt, FGF, TGFβ/BMP, and retinoic acid pathways), and/or to the homeobox gene superfamily, were also uncovered when a less stringent fold change threshold was used. Differential expressions for 10 out of 12 (mandibular incisors versus molars) and 9 out of 10 selected genes were confirmed by quantitative reverse transcription-PCR (qRT-PCR). A bioinformatics tool (Ingenuity Pathway Analysis) used to analyze biological functions and pathways on the group of incisor versus molar differentially expressed genes revealed that 143 genes belonged to 9 networks with intermolecular connections. Networks with the highest significance scores were centered on the TNF/NFκB complex and the ERK1/2 kinases. Two networks ERK1/2 kinases and tretinoin were involved in differential molar morphogenesis. Conclusion These data allowed us to build several regulatory networks that may distinguish incisor versus molar identity, and may be useful for further investigations of these tooth-specific ontogenetic programs. These programs may be dysregulated in transgenic animal models and related human diseases leading to dental anomalies.
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Affiliation(s)
- Virginie Laugel-Haushalter
- Developmental Biology and Stem Cells Department, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, BP 10142, 1 rue Laurent Fries, Illkirch Cedex, 67404, France
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Cammas L, Romand R, Fraulob V, Mura C, Dollé P. Expression of the murine retinol dehydrogenase 10 (Rdh10) gene correlates with many sites of retinoid signalling during embryogenesis and organ differentiation. Dev Dyn 2008; 236:2899-908. [PMID: 17849458 DOI: 10.1002/dvdy.21312] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Retinoic acid acts as a signalling molecule regulating many developmental events in vertebrates. As this molecule directly influences gene expression by activating nuclear receptors, its patterns of synthesis have to be tightly regulated, and it is well established that at least three retinaldehyde dehydrogenases (RALDHs) are involved in such tissue-specific synthesis. Whereas embryos from oviparous species can obtain retinaldehyde by metabolizing carotenoids stored in the yolk, placental embryos rely on retinol transferred from the maternal circulation. Here, we show that the gene encoding one of the murine retinol dehydrogenases, Rdh10, is expressed according to complex profiles both during early embryogenesis and organ differentiation. Many of its expression sites correlate with regions of active retinoid signalling and Raldh gene expression, especially with Raldh2 in the early presomitic and somitic mesoderm, retrocardiac and posterior branchial arch region, or later in the pleural mesothelium and kidney cortical region. Rdh10 also shows cell-type and/or regional specificity during development of the palate, teeth, and olfactory system. During limb bud development, it may participate in retinoic acid production in proximal/posterior cells, and eventually in interdigital mesenchyme. These data implicate the retinol to retinaldehyde conversion as the first step in the tissue-specific regulation of retinoic acid synthesis, at least in mammalian embryos.
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Affiliation(s)
- Laura Cammas
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Inserm, U596, CNRS, UMR 7104, Illkirch, France
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Dieplinger B, Schiefermeier N, Juchum-Pasquazzo M, Gstir R, Huber LA, Klimaschewski L, Vietor I. The transcriptional corepressor TPA-inducible sequence 7 regulates adult axon growth through cellular retinoic acid binding protein II expression. Eur J Neurosci 2007; 26:3358-67. [PMID: 18052984 DOI: 10.1111/j.1460-9568.2007.05951.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
TPA-inducible sequence 7 (TIS7) expression is regulated in epithelial cells and acts as a transcriptional corepressor. Using a TIS7 knock-out mouse we demonstrated that TIS7 is involved in the process of muscle regeneration. In this study, we analysed the role of TIS7 in axon regeneration, applying primary neurone cultures derived from adult dorsal root ganglia (DRGs) of TIS7+/+ and TIS7-/- mice. TIS7-/- DRG neurones exhibited a significant decrease in axon initiation and maximal axon extension. In contrast, nerve growth factor-induced axon initiation and branching were significantly enhanced in cultures obtained from TIS7-/- DRGs when compared with wildtype ganglia, suggesting an inhibitory effect of TIS7 on nerve growth factor-stimulated axon growth. TIS7 overexpression in TIS7-/- DRG neurones caused their morphological appearance to revert back to the wildtype phenotype. Furthermore, the expression of cellular retinoic acid binding protein II (CRABP II), previously identified by us as a TIS7 target gene, was up-regulated in adult DRG sensory neurones from TIS7-/- mice. Overexpression of CRABP II in TIS7+/+ neurones strongly increased the number of branch points, making them morphologically similar to TIS7-/- neurones. Based on these results we propose that TIS7 inhibits CRABP II expression during axonal regeneration, thereby modulating retinoic acid signalling. Hence, neurite initiation and branching are regulated by a negative feedback mechanism involving TIS7 and CRABP II.
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Affiliation(s)
- Benjamin Dieplinger
- Biocenter, Division of Cell Biology, Innsbruck Medical University, Fritz-Pregl-Strasse 3, A-6020 Innsbruck, Austria
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Bloch-Zupan A. Genetische Störungen der Zahnentwicklung und Dentition. MED GENET-BERLIN 2007. [DOI: 10.1007/s11825-007-0050-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Zusammenfassung
Die Zähne sind Organe, die aus ektodermalen epithelialen Aussackungen im Bereich des 1. Kiemenbogens entstehen, gesteuert von epitheliomesenchymalen Interaktionen. Dabei spielen zahlreiche Signalmoleküle speziell der 4 großen Familien TGF-β, FGF, Hedgehog und WNT sowie diverse Transkriptionsfaktoren eine Rolle. Eine Beteiligung der Retinoide an der Odontogenese ist durch umfangreiche Befunde belegt, auch wenn die Inaktivierung relevanter Gene in Mausmodellen meist keine Zahnanomalien verursacht. Die Zahnentwicklung wird klassischerweise in verschiedene Stadien eingeteilt: Entstehung der Zahnleiste, der Zahnknospe, der Schmelzkappe, der Schmelzglocke, die Wurzelbildung und der Zahndurchbruch. Anomalien der Zahnentwicklung können isoliert oder gemeinsam mit anderen Symptomen im Zusammenhang mit Syndromen auftreten. Sie können genetisch bedingt sein oder unter Einwirkung teratogener Stoffe während der Bildung und Mineralisierung der Zahnkeime zustande kommen. Dentibukkale Entwicklungsanomalien treten im Kontext seltener Erkrankungen auf und finden zunehmend Beachtung, da sie bei bestimmten Erkrankungen in der Diagnostik und als prädikative Faktoren wichtige Anhaltspunkte geben können. Allerdings ist hierfür eine interdisziplinäre und internationale Kooperation notwendig, die bislang erst in Ansätzen verwirklicht wurde.
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Affiliation(s)
- A. Bloch-Zupan
- Aff1_50 Faculté de Chirurgie Dentaire, Université Louis Pasteur, Centre de référence des manifestations odontologiques des maladies rares, Service de Soins Bucco-Dentaires Centre Hospitalier Universitaire, Hopital Civil 1 Place de l’Hopital 67000 Strasbourg Cedex France
- Aff2_50 grid.420255.4 0000000406382716 Département Génétique et Physiologie IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), Inserm, U596 CNRS, UMR7104 67400 Illkirch France
- Aff3_50 grid.83440.3b 0000000121901201 Eastman Dental Institute Institute of Child Health, University College London UK
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Mesgouez C, Oboeuf M, Mauro N, Colon P, MacDougall M, Machtou P, Sautier JM, Berdal A. Ultrastructural and immunocytochemical characterization of immortalized odontoblast MO6-G3. Int Endod J 2006; 39:453-63. [PMID: 16674740 DOI: 10.1111/j.1365-2591.2006.01089.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
AIM To investigate an immortalized murine odontoblast cell line as a potential alternative for experimental studies on dentinogenesis. METHODOLOGY The MO6-G3 cell line was investigated morphologically over 3, 7, 11 and 42 days of culture, using histochemical localization of dentine sialoprotein (DSP), alkaline phosphatase (AP), type I collagen and actin filaments, histoenzymatic staining and biochemical investigation of AP and finally, transmission and scanning electron microscopy. RESULTS Scanning electron micrographs showed elongated cells. Accordingly, a polarized organization of odontoblasts was observed by transmission electron microscopy, identifying distinct subcellular compartments as described in vivo. The secretion apparatus, which includes cisternae of rough endoplasmic reticulum, Golgi apparatus saccules and secretion vesicles and granules, was longitudinally organized in the supranuclear compartment ending distally in the secretory pole. A cellular process was observed. The investigation of the cytoskeleton network revealed that actin microfilaments were organized in parallel stress fibre oriented depending on the longitudinal axis of the cytoplasm. Immunofluorescent labelling showed a continuous expression of type I collagen, DSP and AP. A unipolar distribution characterized intracellular DSP immunoreactivity. Histoenzymology revealed AP active sites increasing from 3 to 11 days albeit with a moderate level of activity comparatively to the in vivo situation in dental cells. CONCLUSION This cell line MO6-G3 not only showed the criteria of odontoblast phenotype as previously reported but also the characteristic morphodifferentiation pattern of polarized odontoblasts at the cellular level but with an apparent random distribution.
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Affiliation(s)
- C Mesgouez
- Département d'Odontologie Conservatrice-Endodontie, UFR d'Odontologie, Université Paris 7-Denis Diderot, Paris, France.
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Ritchie HH, Park H, Liu J, Bervoets TJM, Bronckers ALJJ. Effects of dexamethasone, vitamin A and vitamin D3 on DSP-PP mRNA expression in rat tooth organ culture. ACTA ACUST UNITED AC 2004; 1679:263-71. [PMID: 15358518 DOI: 10.1016/j.bbaexp.2004.07.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2004] [Revised: 06/28/2004] [Accepted: 07/21/2004] [Indexed: 10/26/2022]
Abstract
Vitamin A, 1,25-dihydroxyvitamin D3 and dexamethasone are well-characterized hydrophobic molecules whose biological actions are mediated via different members of the nuclear hormone receptor family. We report here their actions on tooth formation at the molecular level. We have tested the effects of these compounds on osteopontin (OPN), dentin sialoprotein (DSP-PP), and collagen type I expression in pre-mineralization and mineralization stage rat tooth organ cultures which mirror in vivo developmental patterns. These proteins are all believed to participate in the mineralization of dentin. 1,25-Dihydroxyvitamin D3 up-regulated OPN, but had no effect on DSP-PP mRNA expression. Vitamin A up-regulated DSP-PP expression as did dexamethasone. Dexamethasone also up-regulated collagen type I expression. Our results suggest that 1,25-dihydroxyvitamin D3 does not modulate dentin mineralization by directly affecting DSP-PP expression. Vitamin A likely contributes to dentin mineralization by up-regulating DSP-PP expression. Finally, the up-regulation of DSP-PP expression in tooth germ cultures treated with dexamethasone suggests that its application to patient's dental pulp might promote increased extracellular matrix synthesis and mineralization in the pulp and may explain the narrowing of the dental pulp cavity in patients undergoing long-term dexamethasone administration.
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Affiliation(s)
- H H Ritchie
- Department of Cariology, Restorative Sciences and Endodontics, University of Michigan, Ann Arbor, Michigan 48109-1078, USA.
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Berkovitz BK, Maden M, McCaffery P, Barrett AW. The distribution of retinaldehyde dehydrogenase-2 in rat and human orodental tissues. Arch Oral Biol 2001; 46:1099-104. [PMID: 11684028 DOI: 10.1016/s0003-9969(01)00081-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Retinoic acid is an important signalling molecule in embryological development and continues to be important in the adult animal because it modulates growth and differentiation in many epithelial tissues. The distribution of the enzyme retinaldehyde dehydrogenase-2 (RALDH 2), which is involved in the synthesis of retinoic acid, was studied using immunocytochemical techniques in: (1) the developing orodental region of rats aged between 15 days in utero and 6 months; and (2) in archival human autopsy material consisting of abdominal skin and mucosa from various regions of the mouth. In developing tooth germs, RALDH 2 was absent in the enamel organ and dental papilla, its presence only being noted at the periphery of the dental follicle adjacent to parts of the developing alveolar crypt. In adult teeth, the presence of RALDH 2 was limited to blood vessels in the periodontal ligament. In embryos, the connective tissue beneath the nasal epithelium and the meninges stained strongly positively for RALDH 2, as did the connective tissue beneath nasal epithelium in an adult rat. Both keratinized and non-keratinized human oral epithelia and abdominal skin stained positively for RALDH 2. Staining was present throughout the stratified epithelium, except in the keratinized layer and in the basal layer associated with the dorsal surface of the tongue. In addition, the adnexia as well as the ductal lining of mucous glands stained positively for RALDH 2.
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Affiliation(s)
- B K Berkovitz
- Department of Anatomy, Cell and Human Biology, GKT School of Biomedical Sciences, Henriette Raphael House, Guy's Campus, London Bridge, SE1 1UL, London, UK.
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Ohishi M, Horibe M, Ikedo D, Miyazaki M, Ohishi K, Kataoka M, Kido J, Nagata T. Effect of retinoic acid on osteopontin expression in rat clonal dental pulp cells. J Endod 1999; 25:683-5. [PMID: 10687528 DOI: 10.1016/s0099-2399(99)80355-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We studied the effect of retinoic acid on osteopontin synthesis and the mRNA expression in rat clonal dental pulp cells, RPC-C2A. An immunoprecipitation assay clarified that retinoic acid caused an increase in phosphorylated osteopontin synthesis that was dose-dependent, and marked increases were observed at retinoic acid concentrations of 10(-6) to 10(-5) M (1.7-fold). A Northern blotting analysis revealed a similar pattern of increase in osteopontin mRNA expression of up to 6.2-fold of control levels. Because osteopontin has an important role in the mineralization process, these results suggest that retinoic acid regulates mineralization, which takes place in the pulp cavity, including reparative dentin formation.
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Affiliation(s)
- M Ohishi
- Department of Periodontology and Endodontology, Tokushima University School of Dentistry, Japan
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Kronmiller JE, Nguyen T. Spatial and temporal distribution of Indian hedgehog mRNA in the embryonic mouse mandible. Arch Oral Biol 1996; 41:577-83. [PMID: 8937649 DOI: 10.1016/0003-9969(96)00013-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Hedgehog genes are involved in pattern formation during embryonic development. A recent report showed that Sonic hedgehog is expressed in the mouse mandible in the presumptive incisor region. In the present study, Indian hedgehog (Ihh) transcripts were present from gestational day 9 to 14 in the mouse mandible (reverse transcription/polymerase chain reaction analysis). Ihh mRNA was present in the dental lamina in both incisor and molar regions and in the developing whiskers (in-situ hybridization). Ihh may be involved in the site-specific proliferation of mandibular epithelium during the formation of the dental lamina. This is consistent with the observation that endogenous synthesis of retinoic acid is necessary for the initiation of odontogenesis and that retinoic acid induces hedgehog expression.
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Affiliation(s)
- J E Kronmiller
- Department of Orthodontics, School of Dentistry, Oregon Health Sciences University, Portland 97201, USA
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Kronmiller JE, Nguyen T, Berndt W, Wickson A. Spatial and temporal distribution of sonic hedgehog mRNA in the embryonic mouse mandible by reverse transcription/polymerase chain reaction and in situ hybridization analysis. Arch Oral Biol 1995; 40:831-8. [PMID: 8651887 DOI: 10.1016/0003-9969(95)00053-r] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Hedgehog genes have recently been implicated in the control of pattern formation in many developing organ system. Vertebrate homologues of the Drosophila hedgehog have been identified in mouse and rate embryos. The temporal regulation of sonic hedgehog (mouse homologue) has previously been studied by Northern analysis of whole embryos with varying results. Sonic hedgehog transcript expression in the mouse mandibular process was now characterized using polymerase chain reaction (PCR) an in situ hybridization techniques. PCR analysis revealed transcripts at gestational days 10 and 11, before the formation of the dental lamina, but not at days 12-14, after tooth buds have formed. Transcripts were localized to, primarily, the epithelium in the presumptive incisor region of the mandibular midline at gestational day 10. No mRNA was detected by in situ hybridization techniques in the presumptive molar regions of odontogenic epithelium. Sonic hedgehog expression may be involved in the regulation of pattern formation through establishment of an incisor-molar axis of polarity.
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Affiliation(s)
- J E Kronmiller
- Department of Orthodontics, School of Dentistry, Oregon Health Sciences University, Portland 97201, USA
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Kronmiller JE, Beeman CS, Nguyen T, Berndt W. Blockade of the initiation of murine odontogenesis in vitro by citral, an inhibitor of endogenous retinoic acid synthesis. Arch Oral Biol 1995; 40:645-52. [PMID: 7575237 DOI: 10.1016/0003-9969(95)00015-h] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Endogenous retinoids are present in the embryonic mouse mandible and reach a concentration peak immediately before the formation of the dental lamina. Because exogenous retinoids alter the pattern of the dental lamina and the expression of epidermal growth factor mRNA (a transcript necessary for initiation of odontogenesis), the role of retinoic acid in the initiation of odontogenesis was studied here. Citral (3,7-dimethyl-2,6-octadienal), a known inhibitor of retinoic acid synthesis, was used to block the endogenous synthesis of retinoic acid in the mouse embryonic mandible before the formation of the dental lamina (gestational day 9). A 24-h exposure to citral totally blocked tooth formation in 7/10 mandibles. Reductions of endogenous retinoic acid concentrations were confirmed by high-performance liquid chromatography. Tooth formation was restored by simultaneous treatment with all-trans retinoic acid or 9-cis retinoic acid during the citral exposures (first 24 h of culture). Endogenous retinoic acid is necessary for the initiation of odontogenesis.
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Affiliation(s)
- J E Kronmiller
- Department of Orthodontics, School of Dentistry, Oregon Health Sciences University, Portland 97201, USA
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Kronmiller JE, Nguyen T, Berndt W. Instruction by retinoic acid of incisor morphology in the mouse embryonic mandible. Arch Oral Biol 1995; 40:589-95. [PMID: 7575229 DOI: 10.1016/0003-9969(95)00014-g] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Endogenous retinoids are present in the embryonic mouse mandible and reach a peak in concentration at the time of the formation of the dental lamina. All-trans retinoic acid is present in a 10-fold higher concentration in the future incisor region of the mouse embryonic mandible at day 11.5. It was found here that exogenous all-trans retinoic acid has pleiotropic effects on the pattern of odontogenesis when applied before the formation of the dental lamina. These effects include a change in the pattern of the dental lamina, supernumerary buds and incisors in the diastema region, and replacement of molars with incisors in the molar region. Thus retinoic acid appears to instruct incisor morphology in the mouse embryonic mandible.
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Affiliation(s)
- J E Kronmiller
- Department of Orthodontics, School of Dentistry, Oregon Health Sciences University Portland 97201, USA
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