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Takács R, Kovács P, Ebeid RA, Almássy J, Fodor J, Ducza L, Barrett-Jolley R, Lewis R, Matta C. Ca2+-Activated K+ Channels in Progenitor Cells of Musculoskeletal Tissues: A Narrative Review. Int J Mol Sci 2023; 24:ijms24076796. [PMID: 37047767 PMCID: PMC10095002 DOI: 10.3390/ijms24076796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/01/2023] [Accepted: 04/04/2023] [Indexed: 04/08/2023] Open
Abstract
Musculoskeletal disorders represent one of the main causes of disability worldwide, and their prevalence is predicted to increase in the coming decades. Stem cell therapy may be a promising option for the treatment of some of the musculoskeletal diseases. Although significant progress has been made in musculoskeletal stem cell research, osteoarthritis, the most-common musculoskeletal disorder, still lacks curative treatment. To fine-tune stem-cell-based therapy, it is necessary to focus on the underlying biological mechanisms. Ion channels and the bioelectric signals they generate control the proliferation, differentiation, and migration of musculoskeletal progenitor cells. Calcium- and voltage-activated potassium (KCa) channels are key players in cell physiology in cells of the musculoskeletal system. This review article focused on the big conductance (BK) KCa channels. The regulatory function of BK channels requires interactions with diverse sets of proteins that have different functions in tissue-resident stem cells. In this narrative review article, we discuss the main ion channels of musculoskeletal stem cells, with a focus on calcium-dependent potassium channels, especially on the large conductance BK channel. We review their expression and function in progenitor cell proliferation, differentiation, and migration and highlight gaps in current knowledge on their involvement in musculoskeletal diseases.
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Affiliation(s)
- Roland Takács
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Patrik Kovács
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Rana Abdelsattar Ebeid
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, Semmelweis University, H-1428 Budapest, Hungary
| | - János Fodor
- Department of Physiology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - László Ducza
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
| | - Richard Barrett-Jolley
- Department of Musculoskeletal Biology, Faculty of Health and Life Sciences, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool L69 3GA, UK
| | - Rebecca Lewis
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK
| | - Csaba Matta
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
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Garneau AP, Slimani S, Haydock L, Nsimba-Batomene TR, Préfontaine FCM, Lavoie MM, Tremblay LE, Fiola MJ, Mac-Way F, Isenring P. Molecular mechanisms, physiological roles, and therapeutic implications of ion fluxes in bone cells: Emphasis on the cation-Cl - cotransporters. J Cell Physiol 2022; 237:4356-4368. [PMID: 36125923 PMCID: PMC10087713 DOI: 10.1002/jcp.30879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/25/2022] [Accepted: 09/01/2022] [Indexed: 11/11/2022]
Abstract
Bone turnover diseases are exceptionally prevalent in human and come with a high burden on physical health. While these diseases are associated with a variety of risk factors and causes, they are all characterized by common denominators, that is, abnormalities in the function or number of osteoblasts, osteoclasts, and/or osteocytes. As such, much effort has been deployed in the recent years to understand the signaling mechanisms of bone cell proliferation and differentiation with the objectives of exploiting the intermediates involved as therapeutic preys. Ion transport systems at the external and in the intracellular membranes of osteoblasts and osteoclasts also play an important role in bone turnover by coordinating the movement of Ca2+ , PO4 2- , and H+ ions in and out of the osseous matrix. Even if they sustain the terminal steps of osteoformation and osteoresorption, they have been the object of very little attention in the last several years. Members of the cation-Cl- cotransporter (CCC) family are among the systems at work as they are expressed in bone cells, are known to affect the activity of Ca2+ -, PO4 2- -, and H+ -dependent transport systems and have been linked to bone mass density variation in human. In this review, the roles played by the CCCs in bone remodeling will be discussed in light of recent developments and their potential relevance in the treatment of skeletal disorders.
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Affiliation(s)
- Alexandre P Garneau
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Québec, Canada.,Service de Néphrologie-Transplantation Rénale Adultes, Hôpital Necker-Enfants Malades, AP-HP, Inserm U1151, Université Paris Cité, rue de Sèvres, Paris, France
| | - Samira Slimani
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Québec, Canada
| | - Ludwig Haydock
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Québec, Canada
| | | | | | - Mathilde M Lavoie
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Québec, Canada
| | - Laurence E Tremblay
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Québec, Canada
| | - Marie-Jeanne Fiola
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Québec, Canada
| | - Fabrice Mac-Way
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Québec, Canada
| | - Paul Isenring
- Department of Medicine, Nephrology Research Group, Laval University, Québec, Québec, Canada
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3
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Lewis KJ. Osteocyte calcium signaling - A potential translator of mechanical load to mechanobiology. Bone 2021; 153:116136. [PMID: 34339908 DOI: 10.1016/j.bone.2021.116136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 06/25/2021] [Accepted: 07/27/2021] [Indexed: 10/20/2022]
Abstract
Osteocytes are embedded dendritic bone cells; by virtue of their position in bone tissue, ability to coordinate bone building osteoblasts and resorbing osteoclasts, and sensitivity to tissue level mechanical loading, they serve as the resident bone mechanosensor. The mechanisms osteocytes use to change mechanical loading into biological signals that drive tissue level changes has been well studied over the last 30 years, however the ways loading parameters are encoded at the cellular level are still not fully understood. Calcium signaling is a first messenger signal exhibited by osteocytes in response to mechanical forces. A body of work interrogating the mechanisms of osteocyte calcium signaling exists and is presently expanding, presenting the opportunity to better understand the relationship between calcium signaling characteristics and tuned osteocyte responses to tissue level strain features (e.g. magnitude, duration, frequency). This review covers the history of osteocyte load induced calcium signaling and highlights potential cellular mechanisms used by osteocytes to turn details about loading parameters into biological events.
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Affiliation(s)
- Karl J Lewis
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, United States of America.
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Zhao G, Kaplan A, Greiser M, Lederer WJ. The surprising complexity of KATP channel biology and of genetic diseases. J Clin Invest 2020; 130:1112-1115. [PMID: 32065592 DOI: 10.1172/jci135759] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The ATP-sensitive K+ channel (KATP) is formed by the association of four inwardly rectifying K+ channel (Kir6.x) pore subunits with four sulphonylurea receptor (SUR) regulatory subunits. Kir6.x or SUR mutations result in KATP channelopathies, which reflect the physiological roles of these channels, including but not limited to insulin secretion, cardiac protection, and blood flow regulation. In this issue of the JCI, McClenaghan et al. explored one of the channelopathies, namely Cantu syndrome (CS), which is a result of one kind of KATP channel mutation. Using a knockin mouse model, the authors demonstrated that gain-of-function KATP mutations in vascular smooth muscle resulted in cardiac remodeling. Moreover, they were able to reverse the cardiovascular phenotypes by administering the KATP channel blocker glibenclamide. These results exemplify how genetic mutations can have an impact on developmental trajectories, and provide a therapeutic approach to mitigate cardiac hypertrophy in cases of CS.
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Affiliation(s)
- Guiling Zhao
- Center for Biomedical Engineering and Technology and Department of Physiology
| | - Aaron Kaplan
- Center for Biomedical Engineering and Technology and Department of Physiology.,Department of Medicine and Division of Cardiology, University of Maryland Baltimore, School of Medicine, Baltimore, Maryland, USA
| | - Maura Greiser
- Center for Biomedical Engineering and Technology and Department of Physiology
| | - W Jonathan Lederer
- Center for Biomedical Engineering and Technology and Department of Physiology
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Hardy E, Fernandez-Patron C. Destroy to Rebuild: The Connection Between Bone Tissue Remodeling and Matrix Metalloproteinases. Front Physiol 2020; 11:47. [PMID: 32116759 PMCID: PMC7013034 DOI: 10.3389/fphys.2020.00047] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 01/21/2020] [Indexed: 12/11/2022] Open
Abstract
Bone is a dynamic organ that undergoes constant remodeling, an energetically costly process by which old bone is replaced and localized bone defects are repaired to renew the skeleton over time, thereby maintaining skeletal health. This review provides a general overview of bone’s main players (bone lining cells, osteocytes, osteoclasts, reversal cells, and osteoblasts) that participate in bone remodeling. Placing emphasis on the family of extracellular matrix metalloproteinases (MMPs), we describe how: (i) Convergence of multiple protease families (including MMPs and cysteine proteinases) ensures complexity and robustness of the bone remodeling process, (ii) Enzymatic activity of MMPs affects bone physiology at the molecular and cellular levels and (iii) Either overexpression or deficiency/insufficiency of individual MMPs impairs healthy bone remodeling and systemic metabolism. Today, it is generally accepted that proteolytic activity is required for the degradation of bone tissue in osteoarthritis and osteoporosis. However, it is increasingly evident that inactivating mutations in MMP genes can also lead to bone pathology including osteolysis and metabolic abnormalities such as delayed growth. We argue that there remains a need to rethink the role played by proteases in bone physiology and pathology.
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Affiliation(s)
| | - Carlos Fernandez-Patron
- Department of Biochemistry, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, AB, Canada
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Scala R, Maqoud F, Angelelli M, Latorre R, Perrone MG, Scilimati A, Tricarico D. Zoledronic Acid Modulation of TRPV1 Channel Currents in Osteoblast Cell Line and Native Rat and Mouse Bone Marrow-Derived Osteoblasts: Cell Proliferation and Mineralization Effect. Cancers (Basel) 2019; 11:cancers11020206. [PMID: 30754651 PMCID: PMC6406412 DOI: 10.3390/cancers11020206] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/05/2019] [Accepted: 02/06/2019] [Indexed: 12/28/2022] Open
Abstract
Bisphosphonates (BPs) reduce bone pain and fractures by balancing the osteoblast/osteoclast ratio. The behavior of ion channels in the presence of BPs is not known. To investigate this, the effect of zoledronic acid BP (ZOL) (3 × 10−8 to 5 × 10−4 M) treatment, on ion channels, cell proliferation, and mineralization, has been investigated on preosteoclast-like cells, RAW264.7, preosteoblast-like cells MC3T3-E1, and rat/mouse native bone marrow-derived osteoblasts. In whole-cell patch clamp on cell line- and bone marrow-derived osteoblasts, ZOL potentiated outward currents. On RAW264.7, ZOL (10−4 M)-evoked current was reduced by the Kv channel blocker tetraethylammonium hydrochloride (TEA), but not by the selective TRPV1-channel antagonist capsazepine. On MC3T3-E1 cells and bone marrow-derived osteoblasts, ZOL-evoked current (5 × 10−8 to 10−4 M) was reduced by capsazepine, whereas the selective TRPV1-channel agonist capsaicin potentiated the control current. In the cell proliferation assay, 72 h incubation of RAW264.7 and MC3T3-E1 cells with ZOL reduced proliferation, with IC50 values of 2.62 × 10−7 M and 2.02 × 10−5 M, respectively. Mineralization of MC3T3-E1 cells and bone marrow-derived osteoblasts was observed in the presence of capsaicin and ZOL (5 × 10−8–10−7 M); ZOL effects were antagonized by capsazepine. In summary, the ZOL-induced activation of TRPV1 channel mediates the mineralization of osteoblasts and counterbalances the antiproliferative effects, increasing the IC50. This mechanism is not operative in osteoclasts lacking the TRPV1 channel.
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Affiliation(s)
- Rosa Scala
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari, Via Orabona 4, I-70125 Bari, Italy.
| | - Fatima Maqoud
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari, Via Orabona 4, I-70125 Bari, Italy.
| | - Mariacristina Angelelli
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari, Via Orabona 4, I-70125 Bari, Italy.
| | - Ramon Latorre
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso 2366103, Chile.
| | - Maria Grazia Perrone
- Medicinal Chemistry Section, Department of Pharmacy-Pharmaceutical Sciences, University of Bari, Via Orabona 4, I-70125 Bari, Italy.
| | - Antonio Scilimati
- Medicinal Chemistry Section, Department of Pharmacy-Pharmaceutical Sciences, University of Bari, Via Orabona 4, I-70125 Bari, Italy.
| | - Domenico Tricarico
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari, Via Orabona 4, I-70125 Bari, Italy.
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Wang D, Wang H, Gao F, Wang K, Dong F. ClC-3 Promotes Osteogenic Differentiation in MC3T3-E1 Cell After Dynamic Compression. J Cell Biochem 2016; 118:1606-1613. [PMID: 27922190 DOI: 10.1002/jcb.25823] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 12/02/2016] [Indexed: 11/11/2022]
Abstract
ClC-3 chloride channel has been proved to have a relationship with the expression of osteogenic markers during osteogenesis, persistent static compression can upregulate the expression of ClC-3 and regulate osteodifferentiation in osteoblasts. However, there was no study about the relationship between the expression of ClC-3 and osteodifferentiation after dynamic compression. In this study, we applied dynamic compression on MC3T3-E1 cells to detect the expression of ClC-3, runt-related transcription factor 2 (Runx2), bone morphogenic protein-2 (BMP-2), osteopontin (OPN), nuclear-associated antigen Ki67 (Ki67), and proliferating cell nuclear antigen (PCNA) in biopress system, then we investigated the expression of these genes after dynamic compression with Chlorotoxin (specific ClC-3 chloride channel inhibitor) added. Under transmission electron microscopy, there were more cell surface protrusions, rough surfaced endoplasmic reticulum, mitochondria, Golgi apparatus, abundant glycogen, and lysosomes scattered in the cytoplasm in MC3T3-E1 cells after dynamic compression. The nucleolus was more obvious. We found that ClC-3 was significantly up-regulated after dynamic compression. The compressive force also up-regulated Runx2, BMP-2, and OPN after dynamic compression for 2, 4 and 8 h. The proliferation gene Ki67 and PCNA did not show significantly change after dynamic compression for 8 h. Chlorotoxin did not change the expression of ClC-3 but reduced the expression of Runx2, BMP-2, and OPN after dynamic compression compared with the group without Cltx added. The data from the current study suggested that ClC-3 may promotes osteogenic differentiation in MC3T3-E1 cell after dynamic compression. J. Cell. Biochem. 118: 1606-1613, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Dawei Wang
- Department of Stomatology, Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
| | - Hao Wang
- Department of Stomatology, Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
| | - Feng Gao
- Department of Pathology, Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
| | - Kun Wang
- Department of Stomatology, Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, China
| | - Fusheng Dong
- Department of Oral and Maxillofacial Surgery, Stomatology Hospital of Hebei Medical University, Shijiazhuang 050017, Hebei, China.,Hebei Key Laboratory of Oral Medicine, Shijiazhuang 050017, Hebei, China
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8
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9
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Wang H, Wang R, Wang Z, Liu Q, Mao Y, Duan X. ClC-3 chloride channel functions as a mechanically sensitive channel in osteoblasts. Biochem Cell Biol 2015; 93:558-65. [PMID: 26436462 DOI: 10.1139/bcb-2015-0018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mechanical stimulation usually causes the volume changes of osteoblasts. Whether these volume changes could be sensed by the ClC-3 chloride channel, a volume-sensitive ion channel, and further promote the osteodifferentiation in osteoblasts has not been determined. In this study, we applied persistent static compression on MC3T3-E1 cells to detect the expression changes of ClC-3, osteogenic markers, as well as some molecules related with signaling transduction pathway. We tested the key role of ClC-3 in transferring the mechanical signal to osteoinduction by ClC-3 overexpressing and siRNA technique. We found that ClC-3 level was up-regulated by mechanical stimulation in MC3T3-E1 cells. Mechanical force also up-regulated the mRNA level of osteogenic markers such as alkaline phosphatase (Alp), bone sialoprotein (Bsp), and osteocalcin (Oc), which could be blocked or strengthened by Clcn3 siRNA or overexpressing, and Alp expression was more sensitive to the changes of ClC-3 level. We also found that runt-related transcription factor 2 (Runx2), transforming growth factor beta 1 (TGF-β1), and Wnt pathway might be involved in ClC-3 mediated mechanical transduction in osteoblasts. The data from the current study suggest that the ClC-3 chloride channel acts as a mechanically sensitive channel to regulate osteodifferentiation in osteoblasts.
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Affiliation(s)
- Huan Wang
- a State Key Laboratory of Military Stomatology, Department of Oral Biology, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China.,b State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China
| | - Rong Wang
- a State Key Laboratory of Military Stomatology, Department of Oral Biology, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China
| | - Zhe Wang
- a State Key Laboratory of Military Stomatology, Department of Oral Biology, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China
| | - Qian Liu
- a State Key Laboratory of Military Stomatology, Department of Oral Biology, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China
| | - Yong Mao
- c State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China
| | - Xiaohong Duan
- a State Key Laboratory of Military Stomatology, Department of Oral Biology, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China
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Abstract
Few investigators think of bone as an endocrine gland, even after the discovery that osteocytes produce circulating fibroblast growth factor 23 that targets the kidney and potentially other organs. In fact, until the last few years, osteocytes were perceived by many as passive, metabolically inactive cells. However, exciting recent discoveries have shown that osteocytes encased within mineralized bone matrix are actually multifunctional cells with many key regulatory roles in bone and mineral homeostasis. In addition to serving as endocrine cells and regulators of phosphate homeostasis, these cells control bone remodeling through regulation of both osteoclasts and osteoblasts, are mechanosensory cells that coordinate adaptive responses of the skeleton to mechanical loading, and also serve as a manager of the bone's reservoir of calcium. Osteocytes must survive for decades within the bone matrix, making them one of the longest lived cells in the body. Viability and survival are therefore extremely important to ensure optimal function of the osteocyte network. As we continue to search for new therapeutics, in addition to the osteoclast and the osteoblast, the osteocyte should be considered in new strategies to prevent and treat bone disease.
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Affiliation(s)
- Sarah L Dallas
- PhD, Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th Street, Kansas City, Missouri 64108.
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11
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Matrix-dependent adhesion mediates network responses to physiological stimulation of the osteocyte cell process. Proc Natl Acad Sci U S A 2013; 110:12096-101. [PMID: 23818616 DOI: 10.1073/pnas.1310003110] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Osteocytes are bone cells that form cellular networks that sense mechanical loads distributed throughout the bone tissue. Interstitial fluid flow in the lacunar canalicular system produces focal strains at localized attachment sites around the osteocyte cell process. These regions of periodic attachment between the osteocyte cell membrane and its canalicular wall are sites where pN-level fluid-flow induced forces are generated in vivo. In this study, we show that focally applied forces of this magnitude using a newly developed Stokesian fluid stimulus probe initiate rapid and transient intercellular electrical signals in vitro. Our experiments demonstrate both direct gap junction coupling and extracellular purinergic P2 receptor signaling between MLO-Y4 cells in a connected bone cell network. Intercellular signaling was initiated by pN-level forces applied at integrin attachment sites along both appositional and distal unapposed cell processes, but not initiated at their cell bodies with equivalent forces. Electrical coupling was evident in 58% of all cell pairs tested with appositional connections; coupling strength increased with the increasing number of junctional connections. Apyrase, a nucleotide-degrading enzyme, suppressed and abolished force-induced effector responses, indicating a contribution from ATP released by the stimulated cell. This work extends the understanding of how osteocytes modulate their microenvironment in response to mechanical signals and highlights mechanisms of intercellular relay of mechanoresponsive signals in the bone network.
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Abstract
Osteocytes were the forgotten bone cell until the bone community could become convinced that these cells do serve an important role in bone function and maintenance. In this review we trace the history of osteocyte characterization and present some of the major observations that are leading to the conclusion that these cells are not passive placeholders residing in the bone matrix, but are indeed, major orchestrators of bone remodeling.
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Affiliation(s)
- Dayong Guo
- University of Missouri, Kansas City, MO, USA
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13
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Choi EM, Kim GH, Lee YS. Diazoxide protects against hydrogen peroxide-induced toxicity in the osteoblastic MC3T3-E1 cells. Eur J Pharmacol 2009; 624:45-50. [DOI: 10.1016/j.ejphar.2009.09.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 09/02/2009] [Accepted: 09/14/2009] [Indexed: 11/24/2022]
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14
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Chen JH, Liu C, You L, Simmons CA. Boning up on Wolff's Law: mechanical regulation of the cells that make and maintain bone. J Biomech 2009; 43:108-18. [PMID: 19818443 DOI: 10.1016/j.jbiomech.2009.09.016] [Citation(s) in RCA: 204] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2009] [Indexed: 12/31/2022]
Abstract
Bone tissue forms and is remodeled in response to the mechanical forces that it experiences, a phenomenon described by Wolff's Law. Mechanically induced formation and adaptation of bone tissue is mediated by bone cells that sense and respond to local mechanical cues. In this review, the forces experienced by bone cells, the mechanotransduction pathways involved, and the responses elicited are considered. Particular attention is given to two cell types that have emerged as key players in bone mechanobiology: osteocytes, the putative primary mechanosensors in intact bone; and osteoprogenitors, the cells responsible for bone formation and recently implicated in ectopic calcification of cardiovascular tissues. Mechanoregulation of bone involves a complex interplay between these cells, their microenvironments, and other cell types. Thus, dissection of the role of mechanics in regulating bone cell fate and function, and translation of that knowledge to improved therapies, requires identification of relevant cues, multifactorial experimental approaches, and advanced model systems that mimic the mechanobiological environment.
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Affiliation(s)
- Jan-Hung Chen
- Department of Mechanical & Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, ON, Canada M5S 3G8
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15
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Nin V, Hernández JA, Chifflet S. Hyperpolarization of the plasma membrane potential provokes reorganization of the actin cytoskeleton and increases the stability of adherens junctions in bovine corneal endothelial cells in culture. ACTA ACUST UNITED AC 2009; 66:1087-99. [DOI: 10.1002/cm.20416] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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16
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Three Types of Single Voltage-Dependent Potassium Channels in the Sarcolemma of Frog Skeletal Muscle. J Membr Biol 2009; 228:51-62. [DOI: 10.1007/s00232-009-9158-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Accepted: 01/31/2009] [Indexed: 10/21/2022]
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17
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Hirukawa K, Muraki K, Ohya S, Imaizumi Y, Togari A. Electrophysiological properties of a novel Ca(2+)-activated K(+) channel expressed in human osteoblasts. Calcif Tissue Int 2008; 83:222-9. [PMID: 18787886 DOI: 10.1007/s00223-008-9167-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Accepted: 08/04/2008] [Indexed: 11/28/2022]
Abstract
Intracellular Ca(2+) mobilization plays important roles in cell survival, proliferation, and differentiation of osteoblasts. In this study, we identified a novel type of Ca(2+)-activated K(+) channel in human osteoblasts and investigated its physiological roles. Using RT-PCR methods and single-channel analysis in the patch-clamp technique, we found that BK and IK channels were genetically expressed in human osteoblasts and had electrophysiological properties similar to those reported previously for the channels in other organs (conductance, voltage dependence, and sensitivity to intracellular Ca(2+)). Taking advantage of the fact that ATP induces elevation of the intracellular Ca(2+) concentration in human osteoblasts, we successfully demonstrated that ATP-induced hyperpolarization was effectively inhibited by the IK channel blockers charybdotoxin and clotrimazole and by a P2 purinergic receptor antagonist, suramin, but not by the BK channel blockers tetraethylammonium chloride and iberiotoxin under the current-clamp mode of whole-cell clamp. The present study is the first to demonstrate the electrophysiological properties and functional expression of IK channels in human osteoblasts, findings which suggest that IK channels are regulators of membrane potential that give rise to intracellular Ca(2+) mobilization by physiological stimulation.
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Affiliation(s)
- Koji Hirukawa
- Department of Pharmacology, School of Dentistry, Aichi-Gakuin University, Nagoya, Japan
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18
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Magra M, Hughes S, El Haj AJ, Maffulli N. VOCCs and TREK-1 ion channel expression in human tenocytes. Am J Physiol Cell Physiol 2006; 292:C1053-60. [PMID: 17035301 DOI: 10.1152/ajpcell.00053.2006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Mechanosensitive and voltage-gated ion channels are known to perform important roles in mechanotransduction in a number of connective tissues, including bone and muscle. It is hypothesized that voltage-gated and mechanosensitive ion channels also may play a key role in some or all initial responses of human tenocytes to mechanical stimulation. However, to date there has been no direct investigation of ion channel expression by human tenocytes. Human tenocytes were cultured from patellar tendon samples harvested from five patients undergoing routine total knee replacement surgery (mean age: 66 yr; range: 63-73 yr). RT-PCR, Western blotting, and whole cell electrophysiological studies were performed to investigate the expression of different classes of ion channels within tenocytes. Human tenocytes expressed mRNA and protein encoding voltage-operated calcium channel (VOCC) subunits (Ca alpha(1A), Ca alpha(1C), Ca alpha(1D), Ca alpha(2)delta(1)) and the mechanosensitive tandem pore domain potassium channel (2PK(+)) TREK-1. They exhibit whole cell currents consistent with the functional expression of these channels. In addition, other ionic currents were detected within tenocytes consistent with the expression of a diverse array of other ion channels. VOCCs and TREK channels have been implicated in mechanotransduction signaling pathways in numerous connective tissue cell types. These mechanisms may be present in human tenocytes. In addition, human tenocytes may express other channel currents. Ion channels may represent potential targets for the pharmacological management of chronic tendinopathies.
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Affiliation(s)
- Merzesh Magra
- Institute for Science and Technology in Medicine, Keele University School of Medicine, Hartshill, Stoke-on-Trent, ST4 7QB, UK
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Gu Y, Preston MR, Magnay J, El Haj AJ, Publicover SJ. Hormonally-regulated expression of voltage-operated Ca(2+) channels in osteocytic (MLO-Y4) cells. Biochem Biophys Res Commun 2001; 282:536-42. [PMID: 11401493 DOI: 10.1006/bbrc.2001.4615] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Voltage operated calcium channels (VOCCs) are important in stimulus-response coupling in osteoblasts. We have investigated the expression of VOCCs in the mouse osteocyte cell line, MLO-Y4. Using the whole-cell patch clamp technique we were unable to detect any VOCC currents (n = 436) even in the presence of the L-type VOCC agonist Bay K 8644 (n = 350). Reverse transcription polymerase chain reaction (RT-PCR), using primers to detect alpha(1C), alpha(1D), and alpha(1G) VOCC subunits (all of which are expressed in primary osteoblasts), did not generate detectable products with mRNA from MLO-Y4 cells. However, after treatment with physiological levels of hormones, VOCC alpha(1) subunit mRNAs were detected in MLO-Y4 cells. PTH, 17beta-estradiol, and dexamethasone-treatment induced expression of L-type (alpha(1C), alpha(1D)) subunit transcripts. ATP-treatment induced expression of T-type (alpha(1G)) transcripts. Using whole-cell patch clamp we detected VOCC currents in 5-10% of cells after treatment. Current characteristics (L- or T-type) were consistent with the transcript expressed.
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Affiliation(s)
- Y Gu
- School of Bioscience, University of Birmingham, Birmingham, Edgbaston, B15 2TT, United Kingdom
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