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Martín‐Guerrero E, Tirado‐Cabrera I, Buendía I, Alonso V, Gortázar AR, Ardura JA. Primary cilia mediate parathyroid hormone receptor type 1 osteogenic actions in osteocytes and osteoblasts via Gli activation. J Cell Physiol 2020; 235:7356-7369. [DOI: 10.1002/jcp.29636] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 01/30/2020] [Indexed: 01/04/2023]
Affiliation(s)
- Eduardo Martín‐Guerrero
- Department of Basic Medical Sciences, Bone Physiopathology LaboratoryUniversidad San Pablo‐CEUAlcorcón Madrid Spain
| | - Irene Tirado‐Cabrera
- Department of Basic Medical Sciences, Bone Physiopathology LaboratoryUniversidad San Pablo‐CEUAlcorcón Madrid Spain
| | - Irene Buendía
- Department of Basic Medical Sciences, Bone Physiopathology LaboratoryUniversidad San Pablo‐CEUAlcorcón Madrid Spain
| | - Verónica Alonso
- Department of Basic Medical Sciences, Bone Physiopathology LaboratoryUniversidad San Pablo‐CEUAlcorcón Madrid Spain
- Departamento de Ciencias Médicas Básicas, Facultad de MedicinaUniversidad San Pablo‐CEU, CEU Universities, Campus MonteprincipeAlcorcón Madrid Spain
| | - Arancha R. Gortázar
- Department of Basic Medical Sciences, Bone Physiopathology LaboratoryUniversidad San Pablo‐CEUAlcorcón Madrid Spain
- Departamento de Ciencias Médicas Básicas, Facultad de MedicinaUniversidad San Pablo‐CEU, CEU Universities, Campus MonteprincipeAlcorcón Madrid Spain
| | - Juan A. Ardura
- Department of Basic Medical Sciences, Bone Physiopathology LaboratoryUniversidad San Pablo‐CEUAlcorcón Madrid Spain
- Departamento de Ciencias Médicas Básicas, Facultad de MedicinaUniversidad San Pablo‐CEU, CEU Universities, Campus MonteprincipeAlcorcón Madrid Spain
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Green JD, Tollemar V, Dougherty M, Yan Z, Yin L, Ye J, Collier Z, Mohammed MK, Haydon RC, Luu HH, Kang R, Lee MJ, Ho SH, He TC, Shi LL, Athiviraham A. Multifaceted signaling regulators of chondrogenesis: Implications in cartilage regeneration and tissue engineering. Genes Dis 2015; 2:307-327. [PMID: 26835506 PMCID: PMC4730920 DOI: 10.1016/j.gendis.2015.09.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 09/16/2015] [Indexed: 01/08/2023] Open
Abstract
Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular nature. Current surgical treatment options do not ensure consistent regeneration of hyaline cartilage in favor of fibrous tissue. Here, we review the current understanding of the most important biological regulators of chondrogenesis and their interactions, to provide insight into potential applications for cartilage tissue engineering. These include various signaling pathways, including: fibroblast growth factors (FGFs), transforming growth factor β (TGF-β)/bone morphogenic proteins (BMPs), Wnt/β-catenin, Hedgehog, Notch, hypoxia, and angiogenic signaling pathways. Transcriptional and epigenetic regulation of chondrogenesis will also be discussed. Advances in our understanding of these signaling pathways have led to promising advances in cartilage regeneration and tissue engineering.
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Affiliation(s)
- Jordan D. Green
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Viktor Tollemar
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Mark Dougherty
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Zhengjian Yan
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Liangjun Yin
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Jixing Ye
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
- School of Bioengineering, Chongqing University, Chongqing, China
| | - Zachary Collier
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Maryam K. Mohammed
- The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Rex C. Haydon
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Hue H. Luu
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Richard Kang
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Michael J. Lee
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Sherwin H. Ho
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Tong-Chuan He
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Lewis L. Shi
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
| | - Aravind Athiviraham
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, IL 60637, USA
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Antoniou J, Wang HT, Hadjab I, Aldebeyan S, Alaqeel MA, Meij BP, Tryfonidou MA, Mwale F. The Effects of Naproxen on Chondrogenesis of Human Mesenchymal Stem Cells. Tissue Eng Part A 2015; 21:2136-46. [PMID: 25873236 DOI: 10.1089/ten.tea.2014.0668] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Currently, there are no established treatments to prevent, stop, or even retard the degeneration of articular cartilage in osteoarthritis (OA). Biological repair of the degenerating articular cartilage would be preferable to surgery. There is no benign site where autologous chondrocytes can be harvested and used as a cell source for cartilage repair, leaving mesenchymal stem cells (MSCs) as an attractive option. However, MSCs from OA patients have been shown to constitutively express collagen type X (COL-X), a marker of late-stage chondrocyte hypertrophy. We recently found that naproxen (Npx), but not other nonsteroidal anti-inflammatory drugs, can induce collagen type X alpha 1 (COL10A1) gene expression in bone marrow-derived MSCs from healthy and OA donors. In this study, we determined the effect of Npx on COL10A1 expression and investigated the intracellular signaling pathways that mediate such effect in normal human MSCs during chondrogenesis. MSCs were cultured in standard chondrogenic differentiation media supplemented with or without Npx. Our results show that Npx can regulate chondrogenic differentiation by affecting the gene expression of both Indian hedgehog and parathyroid hormone/parathyroid hormone-related protein signaling pathways in a time-dependent manner, suggesting a complex interaction of different signaling pathways during the process.
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Affiliation(s)
- John Antoniou
- 1 Lady Davis Institute for Medical Research, Jewish General Hospital, McGill University , Montreal, Quebec, Canada .,2 Division of Orthopedic Surgery, McGill University , Montreal, Quebec, Canada
| | - Hong Tian Wang
- 1 Lady Davis Institute for Medical Research, Jewish General Hospital, McGill University , Montreal, Quebec, Canada
| | - Insaf Hadjab
- 1 Lady Davis Institute for Medical Research, Jewish General Hospital, McGill University , Montreal, Quebec, Canada .,3 École Polytechnique , Montreal, Quebec, Canada
| | - Sultan Aldebeyan
- 1 Lady Davis Institute for Medical Research, Jewish General Hospital, McGill University , Montreal, Quebec, Canada .,4 Department of Orthopaedic Surgery, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Motaz A Alaqeel
- 1 Lady Davis Institute for Medical Research, Jewish General Hospital, McGill University , Montreal, Quebec, Canada .,5 Department of Orthopedics, College of Medicine, King Saud University , Riyadh, Saudi Arabia
| | - Björn P Meij
- 6 Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University , Utrecht, The Netherlands
| | - Marianna A Tryfonidou
- 6 Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University , Utrecht, The Netherlands
| | - Fackson Mwale
- 1 Lady Davis Institute for Medical Research, Jewish General Hospital, McGill University , Montreal, Quebec, Canada .,2 Division of Orthopedic Surgery, McGill University , Montreal, Quebec, Canada
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4
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Sirt6 regulates postnatal growth plate differentiation and proliferation via Ihh signaling. Sci Rep 2013; 3:3022. [PMID: 24149372 PMCID: PMC6505680 DOI: 10.1038/srep03022] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 10/02/2013] [Indexed: 01/12/2023] Open
Abstract
Sirtuin 6 (Sirt6) is a mammalian homologue of NAD+-dependent histone deacetylase Sir2. Although Sirt6−/− mice exhibit growth retardation, the role of Sirt6 in cartilage metabolism is unclear. The aim of this study was to investigate the Sirt6 signaling pathway in cartilage metabolism. Immunohistological evaluation of the tibial growth plate in Sirt6−/− mice exhibited impaired proliferation and differentiation of chondrocytes, reduced expression of Indian hedgehog (Ihh), and a senescent phenotype. When Sirt6 was knocked down in chondrocytes in vitro, expression of Ihh and its downstream genes were reduced. Impaired differentiation by Sirt6 silencing was completely rescued by administration of a Hh signal agonist. When sirtuins were activated, chondrocyte differentiation was enhanced together with activation of Ihh signal, and these effects were abrogated by Sirt6 silencing. ChIP assay revealed the affinity of ATF4 to the Ihh promoter was markedly decreased by Sirt6 knockdown. These data indicate Sirt6 directly controls proliferation and differentiation of chondrocytes.
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Takarada T, Kodama A, Hotta S, Mieda M, Shimba S, Hinoi E, Yoneda Y. Clock genes influence gene expression in growth plate and endochondral ossification in mice. J Biol Chem 2012; 287:36081-95. [PMID: 22936800 PMCID: PMC3476276 DOI: 10.1074/jbc.m112.408963] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 08/27/2012] [Indexed: 11/06/2022] Open
Abstract
We have previously shown transient promotion by parathyroid hormone of Period-1 (Per1) expression in cultured chondrocytes. Here we show the modulation by clock genes of chondrogenic differentiation through gene transactivation of the master regulator of chondrogenesis Indian hedgehog (IHH) in chondrocytes of the growth plate. Several clock genes were expressed with oscillatory rhythmicity in cultured chondrocytes and rib growth plate in mice, whereas chondrogenesis was markedly inhibited in stable transfectants of Per1 in chondrocytic ATDC5 cells and in rib growth plate chondrocytes from mice deficient of brain and muscle aryl hydrocarbon receptor nuclear translocator-like (BMAL1). Ihh promoter activity was regulated by different clock gene products, with clear circadian rhythmicity in expression profiles of Ihh in the growth plate. In BMAL1-null mice, a predominant decrease was seen in Ihh expression in the growth plate with a smaller body size than in wild-type mice. BMAL1 deficit led to disruption of the rhythmic expression profiles of both Per1 and Ihh in the growth plate. A clear rhythmicity was seen with Ihh expression in ATDC5 cells exposed to dexamethasone. In young mice defective of BMAL1 exclusively in chondrocytes, similar abnormalities were found in bone growth and Ihh expression. These results suggest that endochondral ossification is under the regulation of particular clock gene products expressed in chondrocytes during postnatal skeletogenesis through a mechanism relevant to the rhythmic Ihh expression.
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Affiliation(s)
- Takeshi Takarada
- From the Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa 920-1192
| | - Ayumi Kodama
- From the Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa 920-1192
| | - Shogo Hotta
- From the Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa 920-1192
| | - Michihiro Mieda
- the Department of Molecular Neuroscience and Integrative Physiology, Faculty of Medicine, Kanazawa University, Kanazawa, Ishikawa 920-8640, and
| | - Shigeki Shimba
- the Department of Health Science, College of Pharmacy, Nihon University, Chiba 274-8555, Japan
| | - Eiichi Hinoi
- From the Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa 920-1192
| | - Yukio Yoneda
- From the Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa 920-1192
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Aad PY, Echternkamp SE, Sypherd DD, Schreiber NB, Spicer LJ. The hedgehog system in ovarian follicles of cattle selected for twin ovulations and births: evidence of a link between the IGF and hedgehog systems. Biol Reprod 2012; 87:79. [PMID: 22811575 DOI: 10.1095/biolreprod.111.096735] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Hedgehog signaling is involved in regulation of ovarian function in Drosophila, but its role in regulating mammalian ovarian folliculogenesis is less clear. Therefore, gene expression of Indian hedgehog (IHH) and its type 1 receptor, patched 1 (PTCH1), were quantified in bovine granulosa (GC) or theca (TC) cells of small (1-5 mm) antral follicles by in situ hybridization and of larger (5-17 mm) antral follicles by real-time RT-PCR from ovaries of cyclic cows genetically selected (Twinner) or not selected (control) for twin ovulations. Expression of IHH mRNA was localized to GC and cumulus cells, whereas PTCH1 mRNA was greater in TC than in GC. Estrogen-active (E-A; follicular fluid concentration of estradiol > progesterone) versus estrogen-inactive follicles had a greater abundance of mRNA for IHH in GC and PTCH1 in TC. Abundance of IHH mRNA in GC was not affected by cow genotype, whereas TC PTCH1 mRNA was less in large E-A follicles of Twinners than in controls. In vitro, estradiol and wingless-type (WNT) 3A increased IHH mRNA in IGF1-treated GC. IGF1 and BMP4 treatments decreased PTCH1 mRNA in small TC. Estradiol and LH increased PTCH1 mRNA in IGF1-treated TC from large and small follicles, respectively. In summary, functional status of ovarian follicles was associated with differences in hedgehog signaling in GC and TC. We hypothesize that as follicles grow and develop, increased free IGF1 may suppress expression of IHH mRNA by GC and PTCH1 mRNA by TC, and these effects are regulated in a paracrine way by estradiol and other intra- and extragonadal factors.
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Affiliation(s)
- Pauline Y Aad
- Department of Animal Science, Oklahoma State University, Stillwater, USA
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7
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Stünkel W, Pan H, Chew SB, Tng E, Tan JH, Chen L, Joseph R, Cheong CY, Ong ML, Lee YS, Chong YS, Saw SM, Meaney MJ, Kwek K, Sheppard AM, Gluckman PD, Holbrook JD. Transcriptome changes affecting Hedgehog and cytokine signalling in the umbilical cord: implications for disease risk. PLoS One 2012; 7:e39744. [PMID: 22808055 PMCID: PMC3393728 DOI: 10.1371/journal.pone.0039744] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 05/25/2012] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Babies born at lower gestational ages or smaller birthweights have a greater risk of poorer health in later life. Both the causes of these sub-optimal birth outcomes and the mechanism by which the effects are transmitted over decades are the subject of extensive study. We investigated whether a transcriptomic signature of either birthweight or gestational age could be detected in umbilical cord RNA. METHODS The gene expression patterns of 32 umbilical cords from Singaporean babies of Chinese ethnicity across a range of birthweights (1698-4151 g) and gestational ages (35-41 weeks) were determined. We confirmed the differential expression pattern by gestational age for 12 genes in a series of 127 umbilical cords of Chinese, Malay and Indian ethnicity. RESULTS We found that the transcriptome is substantially influenced by gestational age; but less so by birthweight. We show that some of the expression changes dependent on gestational age are enriched in signal transduction pathways, such as Hedgehog and in genes with roles in cytokine signalling and angiogenesis. We show that some of the gene expression changes we report are reflected in the epigenome. CONCLUSIONS We studied the umbilical cord which is peripheral to disease susceptible tissues. The results suggest that soma-wide transcriptome changes, preserved at the epigenetic level, may be a mechanism whereby birth outcomes are linked to the risk of adult metabolic and arthritic disease and suggest that greater attention be given to the association between premature birth and later disease risk.
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Affiliation(s)
- Walter Stünkel
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Hong Pan
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Siew Boom Chew
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Emilia Tng
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Jun Hao Tan
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Li Chen
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Roy Joseph
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Clara Y. Cheong
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Mei-Lyn Ong
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Yung Seng Lee
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore
| | - Yap-Seng Chong
- Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore
| | - Seang Mei Saw
- Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, National University Health System, Singapore, Singapore
| | - Michael J. Meaney
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
| | - Kenneth Kwek
- Department of Maternal Fetal Medicine, KK Women’s and Children’s Hospital, Singapore, Singapore
| | | | - Peter D. Gluckman
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | | | - Joanna D. Holbrook
- Singapore Institute for Clinical Sciences, Agency for Science Technology and Research, Singapore, Singapore
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Wu SM, Choo ABH, Yap MGS, Chan KKK. Role of Sonic hedgehog signaling and the expression of its components in human embryonic stem cells. Stem Cell Res 2009; 4:38-49. [PMID: 19836325 DOI: 10.1016/j.scr.2009.09.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Revised: 09/07/2009] [Accepted: 09/08/2009] [Indexed: 02/08/2023] Open
Abstract
Human embryonic stem cells (hESC) are characterized by their ability to self-renew and differentiate into all cell types of the body, making them a valuable resource for regenerative medicine. Yet, the molecular mechanisms by which hESC retain their capacity for self-renewal and differentiation remain unclear. The Hedgehog signaling pathway plays a pivotal role in organogenesis and differentiation during development, and is also involved in the proliferation and cell-fate specification of neural stem cells and neural crest stem cells. As there has been no detailed study of the Sonic hedgehog (SHH) signaling pathway in hESC, this study examines the expression and functional role of SHH during hESC self-renewal and differentiation. Here, we show the gene and protein expression of key components of the SHH signaling pathway in hESC and differentiated embryoid bodies. Despite the presence of functioning pathway components, SHH plays a minimal role in maintaining pluripotency and regulating proliferation of undifferentiated hESC. However, during differentiation with retinoic acid, a GLI-responsive luciferase assay and target genes PTCH1 and GLI1 expression reveal that the SHH signaling pathway is highly activated. Besides, addition of exogenous SHH to hESC differentiated as embryoid bodies increases the expression of neuroectodermal markers Nestin, SOX1, MAP2, MSI1, and MSX1, suggesting that SHH signaling is important during hESC differentiation toward the neuroectodermal lineage. Our findings provide a new insight in understanding the SHH signaling in hESC and the further development of hESC differentiation for regenerative medicine.
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Affiliation(s)
- Selena Meiyun Wu
- Stem Cell Group, Bioprocessing Technology Institute, ASTAR (Agency for Science, Technology and Research), 20 Biopolis Way, No. 06-01 Centros, Singapore 138668, Singapore
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9
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Takarada T, Hojo H, Iemata M, Sahara K, Kodama A, Nakamura N, Hinoi E, Yoneda Y. Interference by adrenaline with chondrogenic differentiation through suppression of gene transactivation mediated by Sox9 family members. Bone 2009; 45:568-78. [PMID: 19446054 DOI: 10.1016/j.bone.2009.05.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 04/02/2009] [Accepted: 05/04/2009] [Indexed: 11/25/2022]
Abstract
In contrast to osteoblasts, little attention has been paid to the functional expression of adrenergic signaling machineries in chondrocytes. Expression of mRNA was for the first time demonstrated for different adrenergic receptor (AdR) subtypes in chondrogenic ATDC5 cells and mouse metatarsals isolated before vascularization in culture, but not for other molecules related to adrenergic signaling. In neonatal mouse tibial sections, beta(2)AdR and alpha(2a)AdR mRNA expression was found in chondrocytes at different developmental stages by in situ hybridization. Exposure to adrenaline significantly suppressed expression of several maturation markers through the cAMP/protein kinase A pathway activated by beta(2)AdR without affecting cellular proliferation in both cultured ATDC5 cells and metatarsals. Adrenaline also significantly inhibited gene transactivation by sry-type HMG box 9 (Sox9) family members essential for chondrogenic differentiation in a manner prevented by the general betaAdR antagonist propranolol, with a concomitant significant decrease in the levels of Sox6 mRNA and corresponding protein, in ATDC5 cells and primary cultured mouse costal chondrocytes. Systemic administration of propranolol significantly promoted the increased expression of mRNA for collagen I and collagen X, but not for collagen II, in callus of fractured femur in mice. These results suggest that adrenaline may interfere with chondrogenic differentiation through downregulation of Sox6 expression for subsequent suppression of gene transactivation mediated by Sox9 family members after activation of beta(2)AdR expressed by chondrocytes.
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MESH Headings
- Adrenergic beta-2 Receptor Antagonists
- Animals
- Animals, Newborn
- Cell Differentiation
- Cells, Cultured
- Chondrocytes/cytology
- Chondrocytes/metabolism
- Cyclic AMP/metabolism
- Embryo, Mammalian
- Epinephrine/pharmacology
- Fractures, Bone/metabolism
- Fractures, Bone/pathology
- Metatarsal Bones/cytology
- Metatarsal Bones/physiology
- Mice
- RNA, Messenger/biosynthesis
- Receptors, Adrenergic, alpha-2/biosynthesis
- Receptors, Adrenergic, alpha-2/genetics
- Receptors, Adrenergic, beta-2/biosynthesis
- Receptors, Adrenergic, beta-2/genetics
- SOX9 Transcription Factor/physiology
- SOXD Transcription Factors/metabolism
- Signal Transduction
- Tibia/metabolism
- Transcriptional Activation
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Affiliation(s)
- Takeshi Takarada
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School of Natural Science and Technology, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
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10
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Spicer LJ, Sudo S, Aad PY, Wang LS, Chun SY, Ben-Shlomo I, Klein C, Hsueh AJW. The hedgehog-patched signaling pathway and function in the mammalian ovary: a novel role for hedgehog proteins in stimulating proliferation and steroidogenesis of theca cells. Reproduction 2009; 138:329-39. [PMID: 19433502 DOI: 10.1530/rep-08-0317] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The expression of hedgehog (Hh) genes, their receptor, and the co-receptor in mice, rat, and bovine ovaries were investigated. RT-PCR of ovarian transcripts in mice showed amplification of transcripts for Indian (Ihh) and desert (Dhh) Hh, patched 1 (Ptch1), and smoothened (Smo) genes. Semi-quantitative RT-PCR and northern blot analyses showed that whole ovarian Ihh and Dhh transcripts decreased 4-24 h after hCG versus 0-48 h after pregnant mares serum gonadotrophin treatment in mice, whereas mouse Ptch1 and Smo transcripts were expressed throughout the gonadotropin treatments. Quantitative real-time RT-PCR (qRT-PCR) revealed that the expression of the Hh-patched signaling system with Ihh mRNA abundance in granulosa cells was greater, whereas Smo and Ptch1 mRNA abundance was less in theca cells of small versus large follicles of cattle. In cultured rat and bovine theca-interstitial cells, qRT-PCR analyses revealed that the abundance of Gli1 and Ptch1 mRNAs were increased (P<0.05) with sonic hedgehog (SHH) treatment. Additional studies using cultured bovine theca cells indicated that SHH induces proliferation and androstenedione production. IGF1 decreased Ihh mRNA abundance in bovine granulosa cells. The expression and regulation of Ihh transcripts in granulosa cells and Ptch1 mRNA in theca cells suggest a potential paracrine role of this system in bovine follicular development. This study illustrates for the first time Hh activation of Gli1 transcriptional factor in theca cells and its stimulation of theca cell proliferation and androgen biosynthesis.
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Affiliation(s)
- Leon J Spicer
- Department of Animal Science, Oklahoma State University, Stillwater, OK 74078, USA.
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11
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Takahata Y, Takarada T, Iemata M, Yamamoto T, Nakamura Y, Kodama A, Yoneda Y. Functional expression of beta2 adrenergic receptors responsible for protection against oxidative stress through promotion of glutathione synthesis after Nrf2 upregulation in undifferentiated mesenchymal C3H10T1/2 stem cells. J Cell Physiol 2008; 218:268-75. [PMID: 18814142 DOI: 10.1002/jcp.21594] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Adrenaline is believed to play a dual role as a neurotransmitter in the central nervous system and an adrenomedullary hormone in the peripheral tissues. In contrast to accumulating evidence for the involvement in endochondral ossification, osteoblastogenesis, and osteoclastogenesis, little attention has been paid to the role of adrenergic signals in the mechanisms underlying proliferation and differentiation of mesenchymal stem cells with self-renewal capacity and multi-potentiality to differentiate into osteoblast, chondrocyte, adipocyte, and myocyte lineages. Expression of mRNA was seen for different adrenergic receptor (AdR) subtypes, including beta(2)AdR, in the mesenchymal stem cell line C3H10T1/2 cells and mouse bone marrow mesenchymal stem cells before differentiation. Exposure to adrenaline not only increased cAMP formation, phosphorylation of cAMP responsive element (CRE) binding protein (CREB) on serine133 and CRE reporter activity in a manner sensitive to propranolol, but also rendered C3H10T1/2 cells resistant to the cytotoxicity of hydrogen peroxide, but not of either 2,4-dinitirophenol or tunicamycin. Adrenaline induced a rapid but transient increase in mRNA expression of the antioxidative gene nuclear factor E2 p45-related factor-2 (Nrf2) along with an increase in the cystine/glutamate antiporter subunit xCT mRNA expression. Hydrogen peroxide was less cytotoxic in cells overexpressing Nrf2, moreover, while adrenaline significantly increased xCT promoter activity with an increase in endogenous glutathione levels. These results suggest that adrenaline may selectively protect mesenchymal C3H10T1/2 cells from oxidative stress through a mechanism related to the promoted biosynthesis of glutathione in association with transient Nrf2 expression after activation of beta(2)AdR.
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Affiliation(s)
- Yoshifumi Takahata
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School of Natural Science and Technology, Kanazawa, Ishikawa, Japan
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Mau E, Whetstone H, Yu C, Hopyan S, Wunder JS, Alman BA. PTHrP regulates growth plate chondrocyte differentiation and proliferation in a Gli3 dependent manner utilizing hedgehog ligand dependent and independent mechanisms. Dev Biol 2007; 305:28-39. [PMID: 17328886 DOI: 10.1016/j.ydbio.2007.01.031] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2006] [Revised: 01/11/2007] [Accepted: 01/23/2007] [Indexed: 11/30/2022]
Abstract
Growth plate chondrocytes undergo a tightly regulated process of differentiation, allowing for the longitudinal growth of bones. Although it is known that parathyroid hormone related protein (PTHrP) and Indian hedgehog regulate the differentiation of growth plate chondrocytes, how these pathways interact to regulate chondrocyte development is not fully elucidated. We examined how the interaction between PTHrP and the hedgehog activated transcription factors, Gli2 and Gli3, regulates growth plate chondrocyte differentiation and proliferation. Analysis of fetal limbs showed that Gli2 is a negative regulator and Gli3 a positive regulator of type X collagen expression. Limb explant cultures showed that PTHrP treatment inhibited type X collagen expression and increased chondrocyte proliferation. This effect was substantially enhanced in Gli2-/- limbs, was blocked in Gli3-/- limbs, and was only partially inhibited by hedgehog ligand blockade. PTHrP negatively regulated Gli mediated transcription in cell cultures, and regulated the level of the repressor form of Gli3 in a PKA dependent manner. These results show that PTHrP regulates growth plate chondrocyte proliferation and differentiation in part through the activity of Gli3, suggesting a crucial role for Gli3 in growth plate chondrocyte development.
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Affiliation(s)
- Elaine Mau
- The Program in Developmental Biology of the Hospital for Sick Children, Toronto, Ontario, Canada
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Sirchia R, Priulla M, Sciandrello G, Caradonna F, Barbata G, Luparello C. Mid-region parathyroid hormone-related protein (PTHrP) binds chromatin of MDA-MB231 breast cancer cells and isolated oligonucleotides "in vitro". Breast Cancer Res Treat 2006; 105:105-16. [PMID: 17124555 DOI: 10.1007/s10549-006-9437-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2006] [Accepted: 10/24/2006] [Indexed: 10/23/2022]
Abstract
We have previously shown that PTHrP(38-94)-amide restrains growth and invasion "in vitro", causes striking toxicity and accelerates death of some breast cancer cell lines, the most responsive being MDA-MB231 whose tumorigenesis was also attenuated "in vivo". PTHrP(38-94)-amide contains the domain implicated in the nuclear import of PTHrP. Although the nucleus was identified as a destination for mid-region PTHrP, evidence for direct DNA-binding capability is lacking to date. Here, we examined the localization of PTHrP(38-94)-amide within MDA-MB231 cells and within metaphase spread preparations and characterized its DNA-binding properties, employing a combination of immunocytochemical, cytogenetic, "whole genome"/conventional PCR, EMSA and DNase footprinting techniques. The results obtained: (i) show that PTHrP(38-94)-amide gains access to the nuclear compartment of MDA-MB231 cell; (ii) demonstrate that PTHrP(38-94)-amide is a DNA-binding peptide; and, (iii) represent the first data to date on the potential molecular targets in both cellular chromatin and isolated oligonucleotides "in vitro".
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Affiliation(s)
- Rosalia Sirchia
- Dipartimento di Biologia Cellulare e dello Sviluppo, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy
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Tiet TD, Hopyan S, Nadesan P, Gokgoz N, Poon R, Lin AC, Yan T, Andrulis IL, Alman BA, Wunder JS. Constitutive hedgehog signaling in chondrosarcoma up-regulates tumor cell proliferation. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:321-30. [PMID: 16400033 PMCID: PMC1592680 DOI: 10.2353/ajpath.2006.050001] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/21/2005] [Indexed: 12/21/2022]
Abstract
Chondrosarcoma is a malignant cartilage tumor that may arise from benign precursor lesions, such as enchondromas. Some cases of multiple enchondromas are caused by a mutation that results in constitutive activation of Hedgehog-mediated signaling. We found that chondrosarcomas expressed high levels of the Hedgehog target genes PTCH1 and GLI1. Treatment with parathyroid hormone-related protein down-regulated Indian Hedgehog (IHH) expression in normal growth plates but not in chondrosarcoma or enchondroma organ cultures. Treatment of the chondrosarcoma organ cultures with Hedgehog protein increased cell proliferation rate, whereas addition of chemical inhibitors of Hedgehog signaling decreased the proliferation rate. Chondrosarcoma xenografts from 12 different human tumors were established in NOD-SCID mice. Treatment with triparanol, an inhibitor of Hedgehog signaling, resulted in a 60% decrease in tumor volume, a 30% decrease in cellularity, and a 20% reduction in proliferation rate. These results show that Hedgehog signaling is active in chondrosarcoma and benign cartilage tumors and regulates tumor cell proliferation. Our data raise the intriguing possibility that Hedgehog blockade could serve as an effective treatment for chondrosarcoma, a tumor for which there are currently no universally effective nonsurgical management options.
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Affiliation(s)
- Tri Dung Tiet
- The Hospital for Sick Children, 555 University Ave., Suite S107, Toronto, Ontario, Canada, M5G 1X8
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15
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Deckelbaum RA, Majithia A, Booker T, Henderson JE, Loomis CA. The homeoprotein engrailed 1 has pleiotropic functions in calvarial intramembranous bone formation and remodeling. Development 2006; 133:63-74. [PMID: 16319118 DOI: 10.1242/dev.02171] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The membranous bones of the mammalian skull vault arise from discrete condensations of neural crest- and mesodermally-derived cells. Recently, a number of homeodomain transcription factors have been identified as critical regulators of this process. Here, we show that the homeoprotein engrailed 1(EN1) is expressed during embryonic and perinatal craniofacial bone development, where it localizes to the skeletogenic mesenchyme, and,subsequently, to calvarial osteoblasts and osteoprogenitors. Mice lacking En1 exhibit generalized calvarial bone hypoplasia and persistent widening of the sutural joints. A reduction in calvarial membranous bone deposition and mineralization (osteopenia) is coupled to enhanced osteolytic resorption in En1 mutants. Consistent with these observations,expression of established osteoblast differentiation markers reveals that En1 function is required for both early and late phases of calvarial osteogenesis. Further analysis shows that EN1 regulates FGF signaling in calvarial osteoblasts. Moreover, EN1 indirectly influences calvarial osteoclast recruitment and bone resorption by regulating the expression of receptor activator of NFκB ligand (RANKL) in osteoblasts. Thus, during intramembranous bone formation, EN1 acts both cell autonomously and non-cell autonomously. In summary, this study identifies EN1 as a novel modulator of calvarial osteoblast differentiation and proliferation, processes that must be exquisitely balanced to ensure proper skull vault formation.
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Affiliation(s)
- Ron A Deckelbaum
- Department of Cell Biology, New York University School of Medicine, MSB room 614, 550 1st Avenue, New York, NY 10016, USA
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van der Horst G, Farih-Sips H, Löwik CWGM, Karperien M. Multiple mechanisms are involved in inhibition of osteoblast differentiation by PTHrP and PTH in KS483 Cells. J Bone Miner Res 2005; 20:2233-44. [PMID: 16294276 DOI: 10.1359/jbmr.050821] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Revised: 07/28/2005] [Accepted: 08/23/2005] [Indexed: 11/18/2022]
Abstract
UNLABELLED We examined the mechanism by which PTHrP and PTH inhibit KS483 osteoblastic differentiation. We show that PTHrP and PTH inhibit differentiation downstream of early BMP signaling and downregulated components of the hedgehog (Hh) signaling cascade. In addition, PTHrP and PTH repressed RunX2 and osx expression. Overexpression of either gene, however, could not relieve PTHrP and PTH's inhibitory actions. Our data suggest that multiple parallel mechanisms are involved in the inhibition of osteoblast differentiation and matrix mineralization by PTHrP and PTH. INTRODUCTION PTH-related peptide (PTHrP) and PTH are potent inhibitors of osteoblast differentiation in vitro by as yet unexplained mechanisms. MATERIALS AND METHODS We treated murine bone marrow stromal cells and the mesenchymal progenitor cell line KS483 with PTHrP and PTH in combination with either BMPs or hedgehog (Hh) and measured early and late markers of osteoblast differentiation and studied the expression of RunX2 and Osterix (osx). In addition, we examined the PTHrP and PTH response in stable KS483 cells overexpressing either RunX2 or osx. RESULTS PTHrP and PTH inhibited BMP- and Hh-induced osteogenesis downstream of early BMP signaling and by downregulation of components of the Hh signaling cascade. PTHrP and PTH prevented the upregulation of RunX2 expression associated with osteoblast differentiation in an indirect response. However, PTHrP and PTH could still inhibit differentiation, and particularly matrix mineralization, of cells expressing RunX2. In addition, PTHrP and PTH potently downregulated osx expression only in mature osteoblasts in an intermediate early response, but osx overexpression could not relieve the inhibitory effects of PTHrP and PTH on matrix mineralization. CONCLUSIONS Our data suggest that, besides transcriptional repression of RunX2 and osx, other mechanisms in parallel with or downstream of RunX2 and osx are involved in the inhibition of osteoblast differentiation and matrix mineralization by PTHrP and PTH in vitro.
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Affiliation(s)
- Geertje van der Horst
- Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, The Netherlands
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Klüppel M, Wight TN, Chan C, Hinek A, Wrana JL. Maintenance of chondroitin sulfation balance by chondroitin-4-sulfotransferase 1 is required for chondrocyte development and growth factor signaling during cartilage morphogenesis. Development 2005; 132:3989-4003. [PMID: 16079159 DOI: 10.1242/dev.01948] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Glycosaminoglycans (GAGs) such as heparan sulfate and chondroitin sulfate are polysaccharide chains that are attached to core proteins to form proteoglycans. The biosynthesis of GAGs is a multistep process that includes the attachment of sulfate groups to specific positions of the polysaccharide chains by sulfotransferases. Heparan-sulfate and heparan sulfate-sulfotransferases play important roles in growth factor signaling and animal development. However, the biological importance of chondroitin sulfation during mammalian development and growth factor signaling is poorly understood. We show that a gene trap mutation in the BMP-induced chondroitin-4-sulfotransferase 1 (C4st1) gene (also called carbohydrate sulfotransferase 11 - Chst11), which encodes an enzyme specific for the transfer of sulfate groups to the 4-O-position in chondroitin, causes severe chondrodysplasia characterized by a disorganized cartilage growth plate as well as specific alterations in the orientation of chondrocyte columns. This phenotype is associated with a chondroitin sulfation imbalance, mislocalization of chondroitin sulfate in the growth plate and an imbalance of apoptotic signals. Analysis of several growth factor signaling pathways that are important in cartilage growth plate development showed that the C4st1(gt/gt) mutation led to strong upregulation of TGFbeta signaling with concomitant downregulation of BMP signaling, while Indian hedgehog (Ihh) signaling was unaffected. These results show that chondroitin 4-O-sulfation by C4st1 is required for proper chondroitin sulfate localization, modulation of distinct signaling pathways and cartilage growth plate morphogenesis. Our study demonstrates an important biological role of differential chondroitin sulfation in mammalian development.
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Affiliation(s)
- Michael Klüppel
- Programme in Molecular Biology and Cancer, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada
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Lai LP, DaSilva KA, Mitchell J. Regulation of Indian hedgehog mRNA levels in chondrocytic cells by ERK1/2 and p38 mitogen-activated protein kinases. J Cell Physiol 2005; 203:177-85. [PMID: 15389630 DOI: 10.1002/jcp.20208] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Indian hedgehog (Ihh) is produced by growth plate pre-hypertrophic chondrocytes, and is an important regulator of endochondral ossification. However, little is known about the regulation of Ihh in chondrocytes. We have examined the role of integrins and mitogen-activated protein (MAP) kinases in Ihh mRNA regulation in CFK-2 chondrocytic cells. Cells incubated with the beta1-integrin blocking antibody had decreased Ihh mRNA levels, which was accompanied by decreases of activated extracellular signal-regulated kinases (ERK1/2) and activated p38 MAPK. Ihh mRNA levels were also inhibited by U0126, a specific MEK1/2 inhibitor, or SB203580, a specific p38 MAPK inhibitor. Cells transfected with constitutively active MEK1 or MKK3 had increased Ihh mRNA levels, which were diminished by dominant-negative MEK1, p38alpha or p38beta. Stimulation of the PTH1R with 10(-8) M rPTH (1-34) resulted in dephosphorylation of ERK1/2 that was evident within 15 min and sustained for 1 h, as well as transient dephosphorylation of p38 MAPK that was maximal after 25 min. PTH stimulation decreased Ihh mRNA levels, and this effect was blocked by transfecting the cells with constitutively active MEK1 but not by MKK3. These studies demonstrated that activation of ERK1/2 or p38 MAPK increased Ihh mRNA levels. Stimulation of the PTH1R or blocking of beta1-integrin resulted in inhibition of ERK1/2 and p38 MAPK and decreased levels of Ihh mRNA. Our data demonstrate the central role of MAPK in the regulation of Ihh in CFK-2 cells.
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Affiliation(s)
- Lick Pui Lai
- Department of Pharmacology, University of Toronto, Ontario, Canada
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Kartsogiannis V, Ng KW. Cell lines and primary cell cultures in the study of bone cell biology. Mol Cell Endocrinol 2004; 228:79-102. [PMID: 15541574 DOI: 10.1016/j.mce.2003.06.002] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2003] [Accepted: 06/12/2003] [Indexed: 12/13/2022]
Abstract
Bone is a metabolically active and highly organized tissue consisting of a mineral phase of hydroxyapatite and amorphous calcium phosphate crystals deposited in an organic matrix. Bone has two main functions. It forms a rigid skeleton and has a central role in calcium and phosphate homeostasis. The major cell types of bone are osteoblasts, osteoclasts and chondrocytes. In the laboratory, primary cultures or cell lines established from each of these different cell types provide valuable information about the processes of skeletal development, bone formation and bone resorption, leading ultimately, to the formulation of new forms of treatment for common bone diseases such as osteoporosis.
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Abstract
A mixed population of lymphocytes from a healthy donor co-existed with an established culture of allogeneic chondrosarcoma cells, during which time the tumor cells changed from malignantly transformed to benign fibroblast-like morphology; from multilayered to a monolayered growth pattern; lost their potency to grow in colonies in soft agar; and showed signs of senescence. A discussion of possible molecular mechanisms for this event is offered. If there are as yet undiscovered lymphokines that can induce reversal of the malignant geno/phenotype, the cognate gene(s) should be cloned for genetic engineering and for the mass production of the corresponding molecular mediators for clinical trials.
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Affiliation(s)
- Joseph G Sinkovics
- Cancer Institue, St. Joseph's Hospital, Department of Medicine, The University of South Florida College of Medicine, 3001 W Dr Martinr Luther King Jr Blvd, Tampa, USA
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