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Della Morte E, Giannasi C, Valenza A, Cadelano F, Aldegheri A, Zagra L, Niada S, Brini AT. Connexin 43 Modulation in Human Chondrocytes, Osteoblasts and Cartilage Explants: Implications for Inflammatory Joint Disorders. Int J Mol Sci 2024; 25:8547. [PMID: 39126115 PMCID: PMC11313680 DOI: 10.3390/ijms25158547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Revised: 07/31/2024] [Accepted: 08/02/2024] [Indexed: 08/12/2024] Open
Abstract
Connexin 43 (Cx43) is crucial for the development and homeostasis of the musculoskeletal system, where it plays multifaceted roles, including intercellular communication, transcriptional regulation and influencing osteogenesis and chondrogenesis. Here, we investigated Cx43 modulation mediated by inflammatory stimuli involved in osteoarthritis, i.e., 10 ng/mL Tumor Necrosis Factor alpha (TNFα) and/or 1 ng/mL Interleukin-1 beta (IL-1β), in primary chondrocytes (CH) and osteoblasts (OB). Additionally, we explored the impact of synovial fluids from osteoarthritis patients in CH and cartilage explants, providing a more physio-pathological context. The effect of TNFα on Cx43 expression in cartilage explants was also assessed. TNFα downregulated Cx43 levels both in CH and OB (-73% and -32%, respectively), while IL-1β showed inconclusive effects. The reduction in Cx43 levels was associated with a significant downregulation of the coding gene GJA1 expression in OB only (-65%). The engagement of proteasome in TNFα-induced effects, already known in CH, was also observed in OB. TNFα treatment significantly decreased Cx43 expression also in cartilage explants. Of note, Cx43 expression was halved by synovial fluid in both CH and cartilage explants. This study unveils the regulation of Cx43 in diverse musculoskeletal cell types under various stimuli and in different contexts, providing insights into its modulation in inflammatory joint disorders.
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Affiliation(s)
- Elena Della Morte
- Laboratory of Biotechnological Applications, IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy; (E.D.M.); (C.G.); (A.V.); (F.C.); (A.T.B.)
| | - Chiara Giannasi
- Laboratory of Biotechnological Applications, IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy; (E.D.M.); (C.G.); (A.V.); (F.C.); (A.T.B.)
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20129 Milan, Italy
| | - Alice Valenza
- Laboratory of Biotechnological Applications, IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy; (E.D.M.); (C.G.); (A.V.); (F.C.); (A.T.B.)
| | - Francesca Cadelano
- Laboratory of Biotechnological Applications, IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy; (E.D.M.); (C.G.); (A.V.); (F.C.); (A.T.B.)
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20129 Milan, Italy
| | - Alessandro Aldegheri
- Hip Department, IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy; (A.A.); (L.Z.)
| | - Luigi Zagra
- Hip Department, IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy; (A.A.); (L.Z.)
| | - Stefania Niada
- Laboratory of Biotechnological Applications, IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy; (E.D.M.); (C.G.); (A.V.); (F.C.); (A.T.B.)
| | - Anna Teresa Brini
- Laboratory of Biotechnological Applications, IRCCS Istituto Ortopedico Galeazzi, 20157 Milan, Italy; (E.D.M.); (C.G.); (A.V.); (F.C.); (A.T.B.)
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20129 Milan, Italy
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Liu J, Wang X, Jiang W, Azoitei A, Eiseler T, Eckstein M, Hartmann A, Stilgenbauer S, Elati M, Hohwieler M, Kleger A, John A, Wezel F, Zengerling F, Bolenz C, Günes C. Impairment of α-tubulin and F-actin interactions of GJB3 induces aneuploidy in urothelial cells and promotes bladder cancer cell invasion. Cell Mol Biol Lett 2024; 29:94. [PMID: 38956497 PMCID: PMC11218312 DOI: 10.1186/s11658-024-00609-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 06/14/2024] [Indexed: 07/04/2024] Open
Abstract
BACKGROUND We have previously identified an unsuspected role for GJB3 showing that the deficiency of this connexin protein induces aneuploidy in human and murine cells and accelerates cell transformation as well as tumor formation in xenograft models. The molecular mechanisms by which loss of GJB3 leads to aneuploidy and cancer initiation and progression remain unsolved. METHODS GJB3 expression levels were determined by RT-qPCR and Western blot. The consequences of GJB3 knockdown on genome instability were assessed by metaphase chromosome counting, multinucleation of cells, by micronuclei formation and by the determination of spindle orientation. Interactions of GJB3 with α-tubulin and F-actin was analyzed by immunoprecipitation and immunocytochemistry. Consequences of GJB3 deficiency on microtubule and actin dynamics were measured by live cell imaging and fluorescence recovery after photobleaching experiments, respectively. Immunohistochemistry was used to determine GJB3 levels on human and murine bladder cancer tissue sections. Bladder cancer in mice was chemically induced by BBN-treatment. RESULTS We find that GJB3 is highly expressed in the ureter and bladder epithelium, but it is downregulated in invasive bladder cancer cell lines and during tumor progression in both human and mouse bladder cancer. Downregulation of GJB3 expression leads to aneuploidy and genomic instability in karyotypically stable urothelial cells and experimental modulation of GJB3 levels alters the migration and invasive capacity of bladder cancer cell lines. Importantly, GJB3 interacts both with α-tubulin and F-actin. The impairment of these interactions alters the dynamics of these cytoskeletal components and leads to defective spindle orientation. CONCLUSION We conclude that deregulated microtubule and actin dynamics have an impact on proper chromosome separation and tumor cell invasion and migration. Consequently, these observations indicate a possible role for GJB3 in the onset and spreading of bladder cancer and demonstrate a molecular link between enhanced aneuploidy and invasive capacity cancer cells during tumor cell dissemination.
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Affiliation(s)
- Junnan Liu
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany
- Department of Urology, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
| | - Xue Wang
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany
- Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine and Science, Rochester, MN, USA
| | - Wencheng Jiang
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany
| | - Anca Azoitei
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany
| | - Tim Eiseler
- Department of Internal Medicine I, Ulm University Hospital, Ulm, Germany
| | - Markus Eckstein
- Institute of Pathology, Friedrich-Alexander University, Erlangen, Germany
| | - Arndt Hartmann
- Institute of Pathology, Friedrich-Alexander University, Erlangen, Germany
| | | | - Mohamed Elati
- CANTHER, ONCOLille Institute, University of Lille, CNRS, UMR 1277, Inserm U9020, 59045, Lille Cedex, France
| | - Meike Hohwieler
- Institute of Molecular Oncology and Stem Cell Biology, Ulm University Hospital, Ulm, Germany
| | - Alexander Kleger
- Institute of Molecular Oncology and Stem Cell Biology, Ulm University Hospital, Ulm, Germany
| | - Axel John
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany
| | - Felix Wezel
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany
| | - Friedemann Zengerling
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany
| | - Christian Bolenz
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany
| | - Cagatay Günes
- Department of Urology, Ulm University Hospital, Helmholtzstr. 10, 89081, Ulm, Germany.
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Zhao D, Wu J, Acosta FM, Xu H, Jiang JX. Connexin 43 hemichannels and prostaglandin E 2 release in anabolic function of the skeletal tissue to mechanical stimulation. Front Cell Dev Biol 2023; 11:1151838. [PMID: 37123401 PMCID: PMC10133519 DOI: 10.3389/fcell.2023.1151838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/05/2023] [Indexed: 05/02/2023] Open
Abstract
Bone adapts to changes in the physical environment by modulating remodeling through bone resorption and formation to maintain optimal bone mass. As the most abundant connexin subtype in bone tissue, connexin 43 (Cx43)-forming hemichannels are highly responsive to mechanical stimulation by permitting the exchange of small molecules (<1.2 kDa) between bone cells and the extracellular environment. Upon mechanical stimulation, Cx43 hemichannels facilitate the release of prostaglandins E2 (PGE2), a vital bone anabolic factor from osteocytes. Although most bone cells are involved in mechanosensing, osteocytes are the principal mechanosensitive cells, and PGE2 biosynthesis is greatly enhanced by mechanical stimulation. Mechanical stimulation-induced PGE2 released from osteocytic Cx43 hemichannels acts as autocrine effects that promote β-catenin nuclear accumulation, Cx43 expression, gap junction function, and protects osteocytes against glucocorticoid-induced osteoporosis in cultured osteocytes. In vivo, Cx43 hemichannels with PGE2 release promote bone formation and anabolism in response to mechanical loading. This review summarizes current in vitro and in vivo understanding of Cx43 hemichannels and extracellular PGE2 release, and their roles in bone function and mechanical responses. Cx43 hemichannels could be a significant potential new therapeutic target for treating bone loss and osteoporosis.
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Affiliation(s)
- Dezhi Zhao
- School of Medicine, Northwest University, Xi’an, China
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
- School of Life Sciences, Northwestern Polytechnical University, Xi’an, China
| | - Jiawei Wu
- School of Medicine, Northwest University, Xi’an, China
| | - Francisca M. Acosta
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
| | - Huiyun Xu
- School of Life Sciences, Northwestern Polytechnical University, Xi’an, China
| | - Jean X. Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX, United States
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Hua R, Gu S, Jiang JX. Connexin 43 Hemichannels Regulate Osteoblast to Osteocyte Differentiation. Front Cell Dev Biol 2022; 10:892229. [PMID: 35693933 PMCID: PMC9184820 DOI: 10.3389/fcell.2022.892229] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/18/2022] [Indexed: 11/13/2022] Open
Abstract
Connexin 43 (Cx43) is the predominant connexin subtype expressed in osteocytes. Osteocytes, accounting for 90%–95% of total bone cells, function as orchestrators coordinating balanced activity between bone-resorbing osteoclasts and bone-forming osteoblasts. In this study, two newly developed osteocytic cell lines, OCY454 and IDG-SW3, were used to determine the role of Cx43 gap junctions and hemichannels (HCs) in the regulation of osteoblast to osteocyte differentiation. We found that the Cx43 level was substantially increased during the differentiation of IDG-SW3 cells and is also much higher than that of OCY454 cells. We knocked down Cx43 expression using the lentiviral CRISPR/Cas9 approach and inhibition of Cx43 HCs using Cx43 (E2) antibody in IDG-SW3 cells. Cx43 knockdown (KD) or Cx43 HC inhibition decreased gene expression for osteoblast and osteocyte markers, including alkaline phosphatase, type I collagen, dentin matrix protein 1, sclerostin, and fibroblast growth factor 23, whereas increasing the osteoclastogenesis indicator and the receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) ratio at early and late differentiation stages. Moreover, mineralization was remarkably attenuated in differentiated Cx43-deficient IDG-SW3 cells compared to ROSA26 control. The conditioned medium collected from fully differentiated IDG-SW3 cells with Cx43 KD promoted osteoclastogenesis of RAW264.7 osteoclast precursors. Our results demonstrated that Cx43 HCs play critical roles in osteoblast to osteocyte differentiation process and regulate osteoclast differentiation via secreted factors.
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Shi Y, Yu Y, Zhou Y, Zhao J, Zhang W, Zou D, Song W, Wang S. A single-cell interactome of human tooth germ from growing third molar elucidates signaling networks regulating dental development. Cell Biosci 2021; 11:178. [PMID: 34600587 PMCID: PMC8487529 DOI: 10.1186/s13578-021-00691-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 09/16/2021] [Indexed: 01/17/2023] Open
Abstract
Background Development of dental tissue is regulated by extensive cell crosstalk based on various signaling molecules, such as bone morphogenetic protein (BMP) and fibroblast growth factor (FGF) pathways. However, an intact network of the intercellular regulation is still lacking. Result To gain an unbiased and comprehensive view of this dental cell interactome, we applied single-cell RNA-seq on immature human tooth germ of the growing third molar, discovered refined cell subtypes, and applied multiple network analysis to identify the central signaling pathways. We found that immune cells made up over 80% of all tooth germ cells, which exhibited profound regulation on dental cells via Transforming growth factor-β, Tumor necrosis factor (TNF) and Interleukin-1. During osteoblast differentiation, expression of genes related to extracellular matrix and mineralization was continuously elevated by signals from BMP and FGF family. As for the self-renewal of apical papilla stem cell, BMP-FGFR1-MSX1 pathway directly regulated the G0-to-S cell cycle transition. We also confirmed that Colony Stimulating Factor 1 secreted from pericyte and TNF Superfamily Member 11 secreted from osteoblast regulated a large proportion of genes related to osteoclast transformation from macrophage and monocyte. Conclusions We constructed the intercellular signaling networks that regulated the essential developmental process of human tooth, which served as a foundation for future dental regeneration engineering and the understanding of oral pathology. Supplementary Information The online version contains supplementary material available at 10.1186/s13578-021-00691-5.
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Affiliation(s)
- Yueqi Shi
- Department of Oral Surgery, Shanghai Key Laboratory of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, College of Stomatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Department of Stomatology, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200336, China
| | - Yejia Yu
- Department of Oral Surgery, Shanghai Key Laboratory of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, College of Stomatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yuqiong Zhou
- Department of Oral Surgery, Shanghai Key Laboratory of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, College of Stomatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jun Zhao
- Department of Orthodontics, Shanghai Key Laboratory of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, College of Stomatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Wenjie Zhang
- Department of Prosthodontics, Shanghai Key Laboratory of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, College of Stomatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Duohong Zou
- Department of Oral Surgery, Shanghai Key Laboratory of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, College of Stomatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Weichen Song
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Shaoyi Wang
- Department of Oral Surgery, Shanghai Key Laboratory of Stomatology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, College of Stomatology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
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Seifi Moroudi R, Ansari Mahyari S, Vaez Torshizi R, Lanjanian H, Masoudi-Nejad A. Identification of new genes and quantitative trait locis associated with growth curve parameters in F2 chicken population using genome-wide association study. Anim Genet 2021; 52:171-184. [PMID: 33428266 DOI: 10.1111/age.13038] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/26/2020] [Indexed: 11/30/2022]
Abstract
The markers which are correlated with the growth curve parameters help in understanding the characteristics of individual growth during the rearing of livestock. This study aimed to identify a set of biomarkers through a GWAS for growth curve parameters in crossbred chickens using the Illumnia 60K chicken SNP Beadchip. Growth data were collected from a total of 301 birds from cross of a broiler line and native chickens. Using the Gompertz-Laird model, two growth curve parameters, the instantaneous growth rate per day (L) and the coefficient of relative growth or maturing index (k), were estimated. The L and k were used to estimate five derived parameters, namely asymptotic (mature) body weight, body weight at inflection point, age at the inflection point, average growth rate and maximum growth rate. These parameters were considered as phenotypic values in the GWAS based on generalized linear models. The results of the GWAS indicated 21 significant markers, which were located near or within 46 genes. A number of these genes, such as GH, RET, GRB14, FTSJ3 and CCK, are important for growth and meat quality in chickens, and some of them are growth related in other species such as sheep and cattle (GPI, XIRP2, GALNTL6, BMS1, THSD4, TRHDE, SHISA9, ACSL6 and DYNC1LI2). The other genes are associated with developmental biological pathways. These genes are particuarly related to body weight, average daily gain and growth QTL. The results of this study can shed light on the genetic mechanism of biological functions of growth factors in broiler chickens, which is useful for developing management practices and accelerating genetic progress in breeding programs.
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Affiliation(s)
- R Seifi Moroudi
- Department of Animal Science, College of Agriculture, Isfahan University of Technology, PO Box 841583111, Isfahan, Iran
| | - S Ansari Mahyari
- Department of Animal Science, College of Agriculture, Isfahan University of Technology, PO Box 841583111, Isfahan, Iran
| | - R Vaez Torshizi
- Department of Animal Science, Faculty of Agriculture, Tarbiat Modares University, Tehran, 14115-336, Iran
| | - H Lanjanian
- Laboratory of Systems Biology and Bioinformatics, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, 1417614411, Iran
| | - A Masoudi-Nejad
- Laboratory of Systems Biology and Bioinformatics, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, 1417614411, Iran
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Moore AC, Wu J, Jewlal E, Barr K, Laird DW, Willmore KE. Effects of Reduced Connexin43 Function on Mandibular Morphology and Osteogenesis in Mutant Mouse Models of Oculodentodigital Dysplasia. Calcif Tissue Int 2020; 107:611-624. [PMID: 32902679 DOI: 10.1007/s00223-020-00753-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 08/29/2020] [Indexed: 10/23/2022]
Abstract
Mutations in the gene encoding the gap-junctional protein connexin43 (Cx43) are the cause of the human disease oculodentodigital dysplasia (ODDD). The mandible is often affected in this disease, with clinical reports describing both mandibular overgrowth and conversely, retrognathia. These seemingly opposing observations underscore our relative lack of understanding of how ODDD affects mandibular morphology. Using two mutant mouse models that mimic the ODDD phenotype (I130T/+ and G60S/+), we sought to uncover how altered Cx43 function may affect mandibular development. Specifically, mandibles of newborn mice were imaged using micro-CT, to enable statistical comparisons of shape. Tissue-level comparisons of key regions of the mandible were conducted using histomorphology, and we quantified the mRNA expression of several cartilage and bone cell differentiation markers. Both G60S/+ and I130T/+ mutant mice had altered mandibular morphology compared to their wildtype counterparts, and the morphological effects were similarly localized for both mutants. Specifically, the biggest phenotypic differences in mutant mice were focused in regions exposed to mechanical forces, such as alveolar bone, muscular attachment sites, and articular surfaces. Histological analyses revealed differences in ossification of the intramembranous bone of the mandibles of both mutant mice compared to their wildtype littermates. However, chondrocyte organization within the secondary cartilages of the mandible was unaffected in the mutant mice. Overall, our results suggest that the morphological differences seen in G60S/+ and I130T/+ mouse mandibles are due to delayed ossification and suggest that mechanical forces may exacerbate the effects of ODDD on the skeleton.
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Affiliation(s)
- Alyssa C Moore
- Department of Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
| | - Jessica Wu
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
| | - Elizabeth Jewlal
- Department of Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
| | - Kevin Barr
- Department of Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
| | - Dale W Laird
- Department of Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
- Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada
| | - Katherine E Willmore
- Department of Anatomy & Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Canada.
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Kobayashi F, Uehara O, Ito C, Furusawa M, Abiko Y, Muramatsu T. DNA methylation of GJA1, BMP2 and BMP4 in a human cementoblast cell line induced by lipopolysaccharide. Int Endod J 2020; 53:804-811. [PMID: 32011747 DOI: 10.1111/iej.13275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 01/30/2020] [Accepted: 01/30/2020] [Indexed: 11/26/2022]
Abstract
AIM To examine DNA methylation of GJA1, BMP2 and BMP4 in human cementoblasts (HCEM) induced by lipopolysaccharide (LPS). METHODOLOGY HCEM were cultured in osteoinduction medium. After 24 h, Escherichia coli LPS (1 μg/mL) was added to the medium, which was changed every 2-3 days. Untreated samples were used as controls. Messenger RNA was extracted after 4 weeks, and quantitative real-time polymerase chain reaction (qRT-PCR) for GJA1, BMP2, BMP4 and DNMT1 was performed. Genomic DNA was extracted after 4 weeks, and quantitative methylation-specific polymerase chain reaction was carried out for GJA1, BMP2 and BMP4. To detect mineralization, alizarin red and alkaline phosphatase staining were performed. The cells were also treated with the DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine (5Aza) and examined. The significance of differences amongst groups was assessed using a two-way analysis of variance (ANOVA) followed by Bonferroni's multiple comparison test with P < 0.05 being significant. RESULTS Decreased expression of mRNA was seen in GJA1, BMP2 and BMP4 after 4 weeks (P < 0.05). DNA hypermethylation was detected in GJA1, BMP2 and BMP4 (P < 0.05). Alizarin red staining and alkaline phosphatase staining revealed decreased mineralization levels in HCEM stimulated with LPS. 5Aza abolished the effects of DNA methylation in HCEM stimulated with LPS. CONCLUSIONS These results suggest that long-term LPS stimulation induces DNA methylation of GJA1, BMP2 and BMP4 in HCEM.
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Affiliation(s)
- F Kobayashi
- Department of Endodontics, Tokyo Dental College, Tokyo, Japan
| | - O Uehara
- Division of Disease Control and Molecular Epidemiology, Department of Oral Growth and Development, Health Sciences University of Hokkaido, Tobetsu, Japan
| | - C Ito
- Oral Health Science Center, Tokyo Dental College, Tokyo, Japan
| | - M Furusawa
- Department of Endodontics, Tokyo Dental College, Tokyo, Japan
| | - Y Abiko
- Division of Oral Medicine and Pathology, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Tobetsu, Japan
| | - T Muramatsu
- Department of Operative Dentistry, Cariology and Pulp Biology, Tokyo Dental College, Tokyo, Japan
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Novel Techniques to Study the Bone-Tumor Microenvironment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1225:1-18. [PMID: 32030644 DOI: 10.1007/978-3-030-35727-6_1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Many cancers commonly metastasize to bone. After entering the bone, cancer cells can interact with surrounding stromal cells, which ultimately influences metastasis progression. Extracellular vesicles, direct cell contact and gap junctions, and cytokines are all mechanisms of intercellular communication that have been observed to occur in the bone microenvironment. These methods of cellular crosstalk can occur between cancer cells and a variety of stromal cells, with each interaction having a different impact on cancer progression. Communication between cancer cells and bone-resident cells has previously been implicated in processes such as cancer cell trafficking and arrest in bone, cancer cell dormancy, cancer cell reactivation, and proliferation. In this chapter we review innovative techniques and model systems that can be used to study bidirectional crosstalk between cancer cells and stromal cells in the bone, with an emphasis specifically on bone-metastatic breast cancer. Investigating how metastatic cancer cells interact with, and are influenced by, the bone microenvironment is crucial to better understanding of the progression of bone metastasis.
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Schlesinger PH, Blair HC, Beer Stolz D, Riazanski V, Ray EC, Tourkova IL, Nelson DJ. Cellular and extracellular matrix of bone, with principles of synthesis and dependency of mineral deposition on cell membrane transport. Am J Physiol Cell Physiol 2019; 318:C111-C124. [PMID: 31532718 DOI: 10.1152/ajpcell.00120.2019] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bone differs from other connective tissues; it is isolated by a layer of osteoblasts that are connected by tight and gap junctions. This allows bone to create dense lamellar type I collagen, control pH, mineral deposition, and regulate water content forming a compact and strong structure. New woven bone formed after degradation of mineralized cartilage is rapidly degraded and resynthesized to impart structural order for local bone strength. Ossification is regulated by thickness of bone units and by patterning via bone morphogenetic receptors including activin, other bone morphogenetic protein receptors, transforming growth factor-β receptors, all part of a receptor superfamily. This superfamily interacts with receptors for additional signals in bone differentiation. Important features of the osteoblast environment were established using recent tools including osteoblast differentiation in vitro. Osteoblasts deposit matrix protein, over 90% type I collagen, in lamellae with orientation alternating parallel or orthogonal to the main stress axis of the bone. Into this organic matrix, mineral is deposited as hydroxyapatite. Mineral matrix matures from amorphous to crystalline hydroxyapatite. This process includes at least two-phase changes of the calcium-phosphate mineral as well as intermediates involving tropocollagen fibrils to form the bone composite. Beginning with initiation of mineral deposition, there is uncertainty regarding cardinal processes, but the driving force is not merely exceeding the calcium-phosphate solubility product. It occurs behind a epithelial-like layer of osteoblasts, which generate phosphate and remove protons liberated during calcium-phosphate salt deposition. The forming bone matrix is discontinuous from the general extracellular fluid. Required adjustment of ionic concentrations and water removal from bone matrix are important details remaining to be addressed.
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Affiliation(s)
| | - Harry C Blair
- Veterans Affairs Medical Center, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Donna Beer Stolz
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Vladimir Riazanski
- Department of Neurobiology, Pharmacology, and Physiology, University of Chicago, Chicago, Illinois
| | - Evan C Ray
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Irina L Tourkova
- Veterans Affairs Medical Center, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Deborah J Nelson
- Department of Neurobiology, Pharmacology, and Physiology, University of Chicago, Chicago, Illinois
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Gago-Fuentes R, Bechberger JF, Varela-Eirin M, Varela-Vazquez A, Acea B, Fonseca E, Naus CC, Mayan MD. The C-terminal domain of connexin43 modulates cartilage structure via chondrocyte phenotypic changes. Oncotarget 2018; 7:73055-73067. [PMID: 27682878 PMCID: PMC5341963 DOI: 10.18632/oncotarget.12197] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 09/16/2016] [Indexed: 12/13/2022] Open
Abstract
Chondrocytes in cartilage and bone cells population express connexin43 (Cx43) and gap junction intercellular communication (GJIC) is essential to synchronize cells for coordinated electrical, mechanical, metabolic and chemical communication in both tissues. Reduced Cx43 connectivity decreases chondrocyte differentiation and defective Cx43 causes skeletal defects. The carboxy terminal domain (CTD) of Cx43 is located in the cytoplasmic side and is key for protein functions. Here we demonstrated that chondrocytes from the CTD-deficient mice, K258stop/Cx43KO and K258stop/K258stop, have reduced GJIC, increased rates of proliferation and reduced expression of collagen type II and proteoglycans. We observed that CTD-truncated mice were significantly smaller in size. Together these results demonstrated that the deletion of the CTD negatively impacts cartilage structure and normal chondrocyte phenotype. These findings suggest that the proteolytic cleavage of the CTD under pathological conditions, such as under the activation of metalloproteinases during tissue injury or inflammation, may account for the deleterious effects of Cx43 in cartilage and bone disorders such as osteoarthritis.
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Affiliation(s)
- Raquel Gago-Fuentes
- CellCOM-SB Research Group, Instituto de Investigación Biomédica de A Coruña (INIBIC), CH-Universitario A Coruña (XXIAC), University of A Coruña, Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84 15006 A Coruña, Spain
| | - John F Bechberger
- Department of Cellular and Physiological Sciences, The Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z3
| | - Marta Varela-Eirin
- CellCOM-SB Research Group, Instituto de Investigación Biomédica de A Coruña (INIBIC), CH-Universitario A Coruña (XXIAC), University of A Coruña, Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84 15006 A Coruña, Spain
| | - Adrian Varela-Vazquez
- CellCOM-SB Research Group, Instituto de Investigación Biomédica de A Coruña (INIBIC), CH-Universitario A Coruña (XXIAC), University of A Coruña, Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84 15006 A Coruña, Spain
| | - Benigno Acea
- CellCOM-SB Research Group, Instituto de Investigación Biomédica de A Coruña (INIBIC), CH-Universitario A Coruña (XXIAC), University of A Coruña, Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84 15006 A Coruña, Spain
| | - Eduardo Fonseca
- CellCOM-SB Research Group, Instituto de Investigación Biomédica de A Coruña (INIBIC), CH-Universitario A Coruña (XXIAC), University of A Coruña, Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84 15006 A Coruña, Spain
| | - Christian C Naus
- Department of Cellular and Physiological Sciences, The Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z3
| | - Maria D Mayan
- CellCOM-SB Research Group, Instituto de Investigación Biomédica de A Coruña (INIBIC), CH-Universitario A Coruña (XXIAC), University of A Coruña, Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84 15006 A Coruña, Spain
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12
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Guerrero J, Oliveira H, Aid R, Bareille R, Siadous R, Letourneur D, Mao Y, Kohn J, Amédée J. Influence of the three‐dimensional culture of human bone marrow mesenchymal stromal cells within a macroporous polysaccharides scaffold on Pannexin 1 and Pannexin 3. J Tissue Eng Regen Med 2018; 12:e1936-e1949. [DOI: 10.1002/term.2625] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 10/30/2017] [Accepted: 11/29/2017] [Indexed: 12/11/2022]
Affiliation(s)
- Julien Guerrero
- Inserm, U1026, Tissue BioengineeringUniversity of Bordeaux Bordeaux Cedex France
- Department of BiomedicineUniversity Hospital Basel, University of Basel Basel Switzerland
| | - Hugo Oliveira
- Inserm, U1026, Tissue BioengineeringUniversity of Bordeaux Bordeaux Cedex France
| | - Rachida Aid
- Inserm U1148, LVTS, X. Bichat HospitalUniversity Paris Diderot F‐75018 Paris, Institut Galilée, University Paris 13, 93430 Villetaneuse Paris Cedex 18; University Paris Diderot, CHUX, Bichat Paris France
| | - Reine Bareille
- Inserm, U1026, Tissue BioengineeringUniversity of Bordeaux Bordeaux Cedex France
| | - Robin Siadous
- Inserm, U1026, Tissue BioengineeringUniversity of Bordeaux Bordeaux Cedex France
| | - Didier Letourneur
- Inserm U1148, LVTS, X. Bichat HospitalUniversity Paris Diderot F‐75018 Paris, Institut Galilée, University Paris 13, 93430 Villetaneuse Paris Cedex 18; University Paris Diderot, CHUX, Bichat Paris France
| | - Yong Mao
- The New Jersey Center for Biomaterials, Department of Chemistry and Chemical BiologyRutgers The State University of New Jersey Piscataway NJ USA
| | - Joachim Kohn
- The New Jersey Center for Biomaterials, Department of Chemistry and Chemical BiologyRutgers The State University of New Jersey Piscataway NJ USA
| | - Joëlle Amédée
- Inserm, U1026, Tissue BioengineeringUniversity of Bordeaux Bordeaux Cedex France
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13
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Abstract
Connexons form the basis of hemichannels and gap junctions. They are composed of six tetraspan proteins called connexins. Connexons can function as individual hemichannels, releasing cytosolic factors (such as ATP) into the pericellular environment. Alternatively, two hemichannel connexons from neighbouring cells can come together to form gap junctions, membrane-spanning channels that facilitate cell-cell communication by enabling signalling molecules of approximately 1 kDa to pass from one cell to an adjacent cell. Connexins are expressed in joint tissues including bone, cartilage, skeletal muscle and the synovium. Indicative of their importance as gap junction components, connexins are also known as gap junction proteins, but individual connexin proteins are gaining recognition for their channel-independent roles, which include scaffolding and signalling functions. Considerable evidence indicates that connexons contribute to the function of bone and muscle, but less is known about the function of connexons in other joint tissues. However, the implication that connexins and gap junctional channels might be involved in joint disease, including age-related bone loss, osteoarthritis and rheumatoid arthritis, emphasizes the need for further research into these areas and highlights the therapeutic potential of connexins.
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Affiliation(s)
- Henry J Donahue
- Department of Biomedical Engineering, Virginia Commonwealth University, 601 West Main Street, Richmond, Virginia 23284, USA
| | - Roy W Qu
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California at Davis, One Shields Avenue, Davis, California 95616, USA
| | - Damian C Genetos
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California at Davis, One Shields Avenue, Davis, California 95616, USA
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14
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Willebrords J, Maes M, Crespo Yanguas S, Vinken M. Inhibitors of connexin and pannexin channels as potential therapeutics. Pharmacol Ther 2017; 180:144-160. [PMID: 28720428 PMCID: PMC5802387 DOI: 10.1016/j.pharmthera.2017.07.001] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
While gap junctions support the exchange of a number of molecules between neighboring cells, connexin hemichannels provide communication between the cytosol and the extracellular environment of an individual cell. The latter equally holds true for channels composed of pannexin proteins, which display an architecture reminiscent of connexin hemichannels. In physiological conditions, gap junctions are usually open, while connexin hemichannels and, to a lesser extent, pannexin channels are typically closed, yet they can be activated by a number of pathological triggers. Several agents are available to inhibit channels built up by connexin and pannexin proteins, including alcoholic substances, glycyrrhetinic acid, anesthetics and fatty acids. These compounds not always strictly distinguish between gap junctions, connexin hemichannels and pannexin channels, and may have effects on other targets as well. An exception lies with mimetic peptides, which reproduce specific amino acid sequences in connexin or pannexin primary protein structure. In this paper, a state-of-the-art overview is provided on inhibitors of cellular channels consisting of connexins and pannexins with specific focus on their mode-of-action and therapeutic potential.
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Affiliation(s)
- Joost Willebrords
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Michaël Maes
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, Belgium.
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15
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Sun YX, Zhang JF, Xu J, Xu LL, Wu TY, Wang B, Pan XH, Li G. MicroRNA-144-3p inhibits bone formation in distraction osteogenesis through targeting Connexin 43. Oncotarget 2017; 8:89913-89922. [PMID: 29163798 PMCID: PMC5685719 DOI: 10.18632/oncotarget.20984] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 08/17/2017] [Indexed: 11/25/2022] Open
Abstract
Distraction osteogenesis (DO), one of effective therapies for bone regeneration, has been received more attention in recent years. However, the underlying mechanism remains elusive. Recently, microRNAs (miRNAs) have been reported to play important roles in regulating osteogenesis and bone formation. We therefore provided the hypothesis that miRNAs could involve in the DO-mediated bone regeneration. After successfully established the DO model of rats, a miRNA microarray was performed to find the differently expressed miRNAs in DO and control groups in this study. As one of the most downregulated miRNAs, miR-144-3p was found to be decreased during osteogenic differentiation in mesenchymal stem cells of rats (rBMSCs) and DO model. And miR-144-3p overexpression suppressed the osteogenesis while its inhibitor promoted osteogenesis. Furthermore, Connexin-43, an essential regulator for osteogenesis, was validated to be a novel target for miR-144-3p. Finally, miR-144-3p inhibitor modified MSCs promoted mineralization of distracted bone in rat DO model. In conclusion, miR-144-3p was found to regulate osteogenesis and inhibition of miR-144-3p resulted in acceleration of mineralization of DO, which not only give clues to understanding the mechanism of DO but also provide a potential therapeutic target in clinical practice.
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Affiliation(s)
- Yu-Xin Sun
- Department of Orthopaedics and Traumatology, Bao-An District People's Hospital, Shenzhen, PR China.,Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, PR China.,The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, PR China
| | - Jin-Fang Zhang
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, PR China.,The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, PR China
| | - Jia Xu
- Department of Orthopaedics Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, PR China
| | - Liang-Liang Xu
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, PR China
| | - Tian-Yi Wu
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, PR China
| | - Bin Wang
- Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, PR China
| | - Xiao-Hua Pan
- Department of Orthopaedics and Traumatology, Bao-An District People's Hospital, Shenzhen, PR China
| | - Gang Li
- Department of Orthopaedics and Traumatology, Bao-An District People's Hospital, Shenzhen, PR China.,Department of Orthopaedics & Traumatology, Li Ka Shing Institute of Health Sciences and Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, PR China.,The CUHK-ACC Space Medicine Centre on Health Maintenance of Musculoskeletal System, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, PR China.,Key Laboratory for Regenerative Medicine, Ministry of Education, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, PR China
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16
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Abstract
PURPOSE OF REVIEW To discuss current knowledge on the role of connexins and pannexins in the musculoskeletal system. RECENT FINDINGS Connexins and pannexins are crucial for the development and maintenance of both bone and skeletal muscle. In bone, the presence of connexin and more recently of pannexin channels in osteoblasts, osteoclasts, and osteocytes has been described and shown to be essential for normal skeletal development and bone adaptation. In skeletal muscles, connexins and pannexins play important roles during development and regeneration through coordinated regulation of metabolic functions via cell-to-cell communication. Further, under pathological conditions, altered expression of these proteins can promote muscle atrophy and degeneration by stimulating inflammasome activity. In this review, we highlight the important roles of connexins and pannexins in the development, maintenance, and regeneration of musculoskeletal tissues, with emphasis on the mechanisms by which these molecules mediate chemical (e.g., ATP and prostaglandin E2) and physical (e.g., mechanical stimulation) stimuli that target the musculoskeletal system and their involvement in the pathophysiological changes in both genetic and acquired diseases.
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Affiliation(s)
- Lilian I Plotkin
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, 635 Barnhill Drive, MS5045, Indianapolis, IN, 46202, USA.
- Roudebush Veterans Administration Medical Center, Indianapolis, Indiana, USA.
- Indiana Center for Musculoskeletal Health, Indianapolis, Indiana, USA.
| | - Hannah M Davis
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, 635 Barnhill Drive, MS5045, Indianapolis, IN, 46202, USA
| | - Bruno A Cisterna
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Av. Alameda 340, Santiago, Chile
| | - Juan C Sáez
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Av. Alameda 340, Santiago, Chile.
- Centro Interdisciplinario de Neurociencias de Valparaíso, Valparaíso, Chile.
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17
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Boucher J, Monvoisin A, Vix J, Mesnil M, Thuringer D, Debiais F, Cronier L. Connexins, important players in the dissemination of prostate cancer cells. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:202-215. [PMID: 28693897 DOI: 10.1016/j.bbamem.2017.06.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/22/2017] [Accepted: 06/29/2017] [Indexed: 12/25/2022]
Abstract
Over the past 50years, increasing experimental evidences have established that connexins (Cxs) and gap junctional intercellular communication (GJIC) ensure an important role in both the onset and development of cancerous processes. In the present review, we focus on the impact of Cxs and GJIC during the development of prostate cancer (PCa), from the primary growth mainly localized in acinar glands and ducts to the distant metastasis mainly concentrated in bone. As observed in several other types of solid tumours, Cxs and especially Cx43 exhibit an ambivalent role with a tumour suppressor effect in the early stages and, conversely, a rather pro-tumoural profile for most of invasion and dissemination steps to secondary sites. We report here the current knowledge on the function of Cxs during PCa cells migration, cytoskeletal dynamics, proteinases activities and the cross talk with the surrounding stromal cells in the microenvironment of the tumour and the bones. In addition, we discuss the role of Cxs in the bone tropism even if the prostate model is rarely used to study the complete sequence of cancer dissemination compared to breast cancer or melanoma. Even if not yet fully understood, these recent findings on Cxs provide new insights into their molecular mechanisms associated with progression and bone targeted behaviour of PCa. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Jonathan Boucher
- Laboratory Signalisation et Transports Ioniques Membranaires (STIM), ERL7368 - CNRS, University of Poitiers, Poitiers, France
| | - Arnaud Monvoisin
- Laboratory Signalisation et Transports Ioniques Membranaires (STIM), ERL7368 - CNRS, University of Poitiers, Poitiers, France
| | - Justine Vix
- Laboratory Signalisation et Transports Ioniques Membranaires (STIM), ERL7368 - CNRS, University of Poitiers, Poitiers, France; Department of Rheumatology, C.H.U. la Milétrie, Poitiers, France
| | - Marc Mesnil
- Laboratory Signalisation et Transports Ioniques Membranaires (STIM), ERL7368 - CNRS, University of Poitiers, Poitiers, France
| | | | - Françoise Debiais
- Laboratory Signalisation et Transports Ioniques Membranaires (STIM), ERL7368 - CNRS, University of Poitiers, Poitiers, France; Department of Rheumatology, C.H.U. la Milétrie, Poitiers, France
| | - Laurent Cronier
- Laboratory Signalisation et Transports Ioniques Membranaires (STIM), ERL7368 - CNRS, University of Poitiers, Poitiers, France.
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18
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Ben Sassi N, González-Recio Ó, de Paz-del Río R, Rodríguez-Ramilo ST, Fernández AI. Associated effects of copy number variants on economically important traits in Spanish Holstein dairy cattle. J Dairy Sci 2016; 99:6371-6380. [DOI: 10.3168/jds.2015-10487] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 04/15/2016] [Indexed: 11/19/2022]
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19
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Willebrords J, Crespo Yanguas S, Maes M, Decrock E, Wang N, Leybaert L, Kwak BR, Green CR, Cogliati B, Vinken M. Connexins and their channels in inflammation. Crit Rev Biochem Mol Biol 2016; 51:413-439. [PMID: 27387655 PMCID: PMC5584657 DOI: 10.1080/10409238.2016.1204980] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Inflammation may be caused by a variety of factors and is a hallmark of a plethora of acute and chronic diseases. The purpose of inflammation is to eliminate the initial cell injury trigger, to clear out dead cells from damaged tissue and to initiate tissue regeneration. Despite the wealth of knowledge regarding the involvement of cellular communication in inflammation, studies on the role of connexin-based channels in this process have only begun to emerge in the last few years. In this paper, a state-of-the-art overview of the effects of inflammation on connexin signaling is provided. Vice versa, the involvement of connexins and their channels in inflammation will be discussed by relying on studies that use a variety of experimental tools, such as genetically modified animals, small interfering RNA and connexin-based channel blockers. A better understanding of the importance of connexin signaling in inflammation may open up towards clinical perspectives.
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Affiliation(s)
- Joost Willebrords
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Michaël Maes
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
| | - Elke Decrock
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Nan Wang
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Ghent
University, De Pintelaan 185, 9000 Ghent, Belgium; Elke Decrock: Tel: +32 9 332 39
73, Nan Wang: Tel: +32 9 332 39 38, Luc Leybaert: Tel: +32 9 332 33 66
| | - Brenda R. Kwak
- Department of Pathology and Immunology and Division of Cardiology,
University of Geneva, Rue Michel-Servet 1, CH-1211 Geneva, Switzerland; Brenda R.
Kwak: Tel: +41 22 379 57 37
| | - Colin R. Green
- Department of Ophthalmology and New Zealand National Eye Centre,
University of Auckland, New Zealand; Colin R. Green: Tel: +64 9 923 61 35
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal
Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87,
05508-270 São Paulo, Brazil; Bruno Cogliati: Tel: +55 11 30 91 12 00
| | - Mathieu Vinken
- Department of In Vitro Toxicology and
Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels,
Belgium; Joost Willebrords: + Tel: 32 2 477 45 87, Michaël Maes: Tel: +32 2
477 45 87, Sara Crespo Yanguas: Tel: +32 2 477 45 87
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20
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Plotkin LI, Laird DW, Amedee J. Role of connexins and pannexins during ontogeny, regeneration, and pathologies of bone. BMC Cell Biol 2016; 17 Suppl 1:19. [PMID: 27230612 PMCID: PMC4896274 DOI: 10.1186/s12860-016-0088-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Electron micrographs revealed the presence of gap junctions in osteoblastic cells over 40 years ago. These intercellular channels formed from connexins are present in bone forming osteoblasts, bone resorbing osteoclasts, and osteocytes (mature osteoblasts embedded in the mineralized bone matrix). More recently, genetic and pharmacologic studies revealed the role of connexins, and in particular Cx43, in the differentiation and function of all bone types. Furthermore, mutations in the gene encoding Cx43 were found to be causally linked to oculodentodigital dysplasia, a condition that results in an abnormal skeleton. Pannexins, molecules with similar structure and single-membrane channel forming potential as connexins when organized as hemichannels, are also expressed in osteoblastic cells. The function of pannexins in bone and cartilage is beginning to be uncovered, but more research is needed to determine the role of pannexins in bone development, adult bone mass and skeletal homeostasis. We describe here the current knowledge on the role of connexins and pannexins on skeletal health and disease.
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Affiliation(s)
- Lilian I Plotkin
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. .,Roudebush Veterans Administration Medical Center Indiana, Indianapolis, IN, 46202, USA.
| | - Dale W Laird
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, N6A-5C1, Canada
| | - Joelle Amedee
- INSERM U1026, Tissue Bioengineering, Université Bordeaux, Bordeaux, F-33076, France
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21
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Abstract
Shaping of the skeleton (modeling) and its maintenance throughout life (remodeling) require coordinated activity among bone forming (osteoblasts) and resorbing cells (osteoclasts) and osteocytes (bone embedded cells). The gap junction protein connexin43 (Cx43) has emerged as a key modulator of skeletal growth and homeostasis. The skeletal developmental abnormalities present in oculodentodigital and craniometaphyseal dysplasias, both linked to Cx43 gene (GJA1) mutations, demonstrate that the skeleton is a major site of Cx43 action. Via direct action on osteolineage cells, including altering production of pro-osteoclastogenic factors, Cx43 contributes to peak bone mass acquisition, cortical modeling of long bones, and maintenance of bone quality. Cx43 also contributes in diverse ways to bone responsiveness to hormonal and mechanical signals. Skeletal biology research has revealed the complexity of Cx43 function; in addition to forming gap junctions and "hemichannels", Cx43 provides a scaffold for signaling molecules. Hence, Cx43 actively participates in generation and modulation of cellular signals driving skeletal development and homeostasis. Pharmacological interference with Cx43 may in the future help remedy deterioration of bone quality occurring with aging, disuse and hormonal imbalances.
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Affiliation(s)
- Joseph P Stains
- Department of Orthopaedics, University of Maryland, School of Medicine, Baltimore, MD, United States
| | - Roberto Civitelli
- Division of Bone and Mineral Diseases, Department of Internal Medicine, Washington University in St. Louis, Campus Box 8301, 425 South Euclid, St. Louis, MO 63110, United States.
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22
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Izu Y, Ezura Y, Koch M, Birk DE, Noda M. Collagens VI and XII form complexes mediating osteoblast interactions during osteogenesis. Cell Tissue Res 2016; 364:623-635. [PMID: 26753503 PMCID: PMC4875952 DOI: 10.1007/s00441-015-2345-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 12/10/2015] [Indexed: 12/17/2022]
Abstract
Bone formation is precisely regulated by cell-cell communication in osteoblasts. We have previously demonstrated that genetic deletion of Col6a1 or Col12a1 impairs osteoblast connections and/or communication in mice, resulting in bone mass reduction and bone fragility. Mutations of the genes encoding collagen VI cause Ullrich congenital muscular dystrophy (UCMD) and Bethlem myopathy (BM), which have overlapping phenotypes involving connective tissue and muscle. Recent studies have identified COL12A1 gene mutations in patients with UCMD- and BM-like disorders harboring no COL6 mutations, indicating the shared functions of these collagens in connective tissue homeostasis. The purpose of this investigation has been to test the hypothesis that collagens VI and XII have coordinate regulatory role(s) during bone formation. We analyzed the localization of collagens VI and XII relative to primary osteoblasts during osteogenesis. Immunofluorescence analysis demonstrated that collagens VI and XII colocalized in matrix bridges between adjacent cells during periods when osteoblasts were establishing cell-cell connections. Quantification of cells harboring collagen bridges demonstrated that matrix bridges were composed of collagens VI and XII but not collagen I. Interestingly, matrix bridge formation was impaired in osteoblasts deficient in either Col6a1 or Col12a1, suggesting that both collagens were indispensable for matrix bridge formation. These data demonstrate, for the first time, a functional relationship between collagens VI and XII during osteogenesis and indicate that a complex containing collagens VI and XII is essential for the formation of a communicating cellular network during bone formation.
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Affiliation(s)
- Yayoi Izu
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, M&D Tower 24th, 5-45 1-Chome Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
| | - Yoichi Ezura
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, M&D Tower 24th, 5-45 1-Chome Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Manuel Koch
- Institute for Dental Research and Musculoskeletal Biology, Center for Biochemistry, University of Cologne, Cologne, Germany
| | - David E Birk
- Department of Molecular Pharmacology & Physiology, University of South Florida, Morsani College of Medicine, Tampa, Florida, USA
| | - Masaki Noda
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, M&D Tower 24th, 5-45 1-Chome Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
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23
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Plotkin LI, Stains JP. Connexins and pannexins in the skeleton: gap junctions, hemichannels and more. Cell Mol Life Sci 2015; 72:2853-67. [PMID: 26091748 PMCID: PMC4503509 DOI: 10.1007/s00018-015-1963-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Accepted: 06/11/2015] [Indexed: 10/23/2022]
Abstract
Regulation of bone homeostasis depends on the concerted actions of bone-forming osteoblasts and bone-resorbing osteoclasts, controlled by osteocytes, cells derived from osteoblasts surrounded by bone matrix. The control of differentiation, viability and function of bone cells relies on the presence of connexins. Connexin43 regulates the expression of genes required for osteoblast and osteoclast differentiation directly or by changing the levels of osteocytic genes, and connexin45 may oppose connexin43 actions in osteoblastic cells. Connexin37 is required for osteoclast differentiation and its deletion results in increased bone mass. Less is known on the role of connexins in cartilage, ligaments and tendons. Connexin43, connexin45, connexin32, connexin46 and connexin29 are expressed in chondrocytes, while connexin43 and connexin32 are expressed in ligaments and tendons. Similarly, although the expression of pannexin1, pannexin2 and pannexin3 has been demonstrated in bone and cartilage cells, their function in these tissues is not fully understood.
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Affiliation(s)
- Lilian I Plotkin
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, 635 Barnhill Dr., MS 5035, Indianapolis, IN, 46202, USA,
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24
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Oh SK, Shin JO, Baek JI, Lee J, Bae JW, Ankamerddy H, Kim MJ, Huh TL, Ryoo ZY, Kim UK, Bok J, Lee KY. Pannexin 3 is required for normal progression of skeletal development in vertebrates. FASEB J 2015; 29:4473-84. [PMID: 26183770 DOI: 10.1096/fj.15-273722] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 06/30/2015] [Indexed: 12/25/2022]
Abstract
The vertebrate skeletal system has various functions, including support, movement, protection, and the production of blood cells. The development of cartilage and bones, the core components of the skeletal system, is mediated by systematic inter- and intracellular communication among multiple signaling pathways in differentiating progenitors and the surrounding tissues. Recently, Pannexin (Panx) 3 has been shown to play important roles in bone development in vitro by mediating multiple signaling pathways, although its roles in vivo have not been explored. In this study, we generated and analyzed Panx3 knockout mice and examined the skeletal phenotypes of panx3 morphant zebrafish. Panx3(-/-) embryos exhibited delays in hypertrophic chondrocyte differentiation and osteoblast differentiation as well as the initiation of mineralization, resulting in shortened long bones in adulthood. The abnormal progression of hypertrophic chondrogenesis appeared to be associated with the sustained proliferation of chondrocytes, which resulted from increased intracellular cAMP levels. Similarly, osteoblast differentiation and mineralization were delayed in panx3 morphant zebrafish. Taken together, our results provide evidence of the crucial roles of Panx3 in vertebrate skeletal development in vivo.
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Affiliation(s)
- Se-Kyung Oh
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jeong-Oh Shin
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jeong-In Baek
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jinwook Lee
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jae Woong Bae
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Harinarayana Ankamerddy
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Myoung-Jin Kim
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Tae-Lin Huh
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Zae-Young Ryoo
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Un-Kyung Kim
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jinwoong Bok
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kyu-Yup Lee
- *Department of Biology, College of Natural Sciences, School of Life Sciences, BrainKorea21 PLUS Project for Kyungpook National University Creative BioResearch Group, School of Life Science and Biotechnology, and Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Kyungpook National University, Daegu, South Korea; Department of Anatomy, BrainKorea21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea; and Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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25
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Osteocytes up-regulate the terminal differentiation of pre-osteoblasts via gap junctions. Biochem Biophys Res Commun 2015; 456:1-6. [DOI: 10.1016/j.bbrc.2014.10.128] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 10/26/2014] [Indexed: 11/21/2022]
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Sadr-Eshkevari P, Ashnagar S, Rashad A, Dietz M, Jackowski J, Abdulazim A, Prochnow N. Bisphosphonates and connexin 43: a critical review of evidence. ACTA ACUST UNITED AC 2014; 21:241-7. [PMID: 24946183 DOI: 10.3109/15419061.2014.927869] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Bisphosphonates (BPs) are drugs commonly used in the treatment of various disease arising or affecting bone tissue. There is a standard use in bone neoplasia and metastasis, hormonal and developmental disorders as well as for compensation of adverse effects in several medical therapies. Many in-vivo and in-vitro studies have assessed the efficacy of this drug and its function in cellular scale. In this concern, BPs are described to inhibit the resorptive function of osteoclasts and to prevent apoptosis of osteoblasts and osteocytes. They can preserve the osteocytic network, reduce fracture rate, and increase the bone mineral content, which is therapeutically used. Connexin 43 (Cx43) is a crucial molecule for basal regulation of bone homeostasis, development, and differentiation. It is described for signal transduction in many physiological and pathological stimuli and recently to be involved in BP action.
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27
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Prashar P, Yadav PS, Samarjeet F, Bandyopadhyay A. Microarray meta-analysis identifies evolutionarily conserved BMP signaling targets in developing long bones. Dev Biol 2014; 389:192-207. [PMID: 24583261 DOI: 10.1016/j.ydbio.2014.02.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 02/07/2014] [Accepted: 02/12/2014] [Indexed: 11/26/2022]
Abstract
In vertebrates, BMP signaling has been demonstrated to be sufficient for bone formation in several tissue contexts. This suggests that genes necessary for bone formation are expressed in a BMP signaling dependent manner. However, till date no gene has been reported to be expressed in a BMP signaling dependent manner in bone. Our aim was to identify such genes. On searching the literature we found that several microarray experiments have been conducted where the transcriptome of osteogenic cells in absence and presence of BMP signaling activation have been compared. However, till date, there is no evidence to suggest that any of the genes found to be upregulated in presence of BMP signaling in these microarray analyses is indeed a target of BMP signaling in bone. We wanted to utilize this publicly available information to identify candidate BMP signaling target genes in vivo. We performed a meta-analysis of six such comparable microarray datasets. This analysis and subsequent experiments led to the identification of five targets of BMP signaling in bone that are conserved both in mouse and chick. Of these Lox, Klf10 and Gpr97 are likely to be direct transcriptional targets of BMP signaling pathway. Dpysl3, is a novel BMP signaling target identified in our study. Our data demonstrate that Dpysl3 is important for osteogenic differentiation of mesenchymal cells and is involved in cell secretion. We have demonstrated that the expression of Dpysl3 is co-operatively regulated by BMP signaling and Runx2. Based on our experimental data, in silico analysis of the putative promoter-enhancer regions of Bmp target genes and existing literature, we hypothesize that BMP signaling collaborates with multiple signaling pathways to regulate the expression of a unique set of genes involved in endochondral ossification.
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Affiliation(s)
- Paritosh Prashar
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Prem Swaroop Yadav
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Fnu Samarjeet
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India
| | - Amitabha Bandyopadhyay
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur 208016, Uttar Pradesh, India.
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28
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Dyce PW, Li D, Barr KJ, Kidder GM. Connexin43 is required for the maintenance of multipotency in skin-derived stem cells. Stem Cells Dev 2014; 23:1636-46. [PMID: 24694074 DOI: 10.1089/scd.2013.0459] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Expression of the gap junction protein, connexin43 (Cx43), begins early during embryogenesis and is maintained in many different cell types. Several stem cell populations have been shown to express Cx43 and to form functional gap junctions. While it is clear that Cx43 is critical to the function of many organs, whether the same is true for stem cells has not been clearly demonstrated. Recently, stem cells isolated from newborn mouse skin were shown to form oocyte-like cells (OLCs) in vitro, hence the present study focussed on the role Cx43 plays in the proliferation and differentiation of these cells. The stem cells express Cx43 and those from knockout mice (Cx43 KO) exhibited significantly reduced cell-cell coupling. Loss of Cx43 reduced the rate of cellular migration [Cx43 KO, 1.57±0.65 radial cell units (RCU); wildtype (WT), 5.57±0.37 RCU] but increased the proliferation rate of the stem cells (Cx43 KO, 29.40%±2.02%; WT, 12.76%±1.50%). The expression of the pluripotency markers OCT4 and Nanog were found to be reduced in the Cx43 KO population, suggesting an inhibition of differentiation potential. To test the differentiation ability, the stem cells were induced to form neuronal cell types in vitro. While both the WT and KO cells were able to form GFAP-positive astrocytic cells, only WT stem cells were able to form βIII tubulin-positive neurons. Similarly, the ability of the stem cells to form OLCs was ablated by the loss of Cx43. These data reveal a role for Cx43 in maintaining multipotency within the skin-derived stem cell population.
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Affiliation(s)
- Paul W Dyce
- 1 Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, The University of Western Ontario , London, Ontario, Canada
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29
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Plotkin LI. Connexin 43 hemichannels and intracellular signaling in bone cells. Front Physiol 2014; 5:131. [PMID: 24772090 PMCID: PMC3983496 DOI: 10.3389/fphys.2014.00131] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 03/15/2014] [Indexed: 12/13/2022] Open
Abstract
Cell function and survival are controlled by intracellular signals, and modulated by surrounding cells and the extracellular environment. Connexin channels participate in these processes by mediating cell-to-cell communication. In bone cells, gap junction channels were detected in the early 1970s, and are present among bone resorbing osteoclasts, bone forming osteoblasts, and osteocytes - mature osteoblasts embedded in the mineralized matrix. These channels are composed mainly by Cx43, although the expression of other connexins (45, 46, and 37) has also been reported. It is now believed that undocked Cx43 hemichannels (connexons) formed in unopposed cell membranes facing the extracellular environment participate in the interaction of bone cells with the extracellular environment, and in their communication with neighboring cells. Thus, we and others demonstrated the presence of active hemichannels in osteoblastic and osteocytic cells. These hemichannels open in response to pharmacological and mechanical stimulation. In particular, preservation of the viability of osteoblasts and osteocytes by the anti-osteoporotic drugs bisphosphonates depends on Cx43 expression in vitro and in vivo, and is mediated by undocked hemichannels. Cx43 hemichannels are also required for the release of prostaglandins and ATP by osteocytes, and for cell survival induced by mechanical stimulation in vitro. Moreover, they are required for the anti-apoptotic effect of parathyroid hormone in osteoblastic cells. This review summarizes the current knowledge on the presence and function of undocked connexons, and the role of hemichannel regulation for the maintenance of bone cell viability and, potentially, bone health.
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Affiliation(s)
- Lilian I. Plotkin
- Department Anatomy and Cell Biology, Indiana University School of MedicineIndianapolis, IN, USA
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30
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Inhibition of GSK-3β rescues the impairments in bone formation and mechanical properties associated with fracture healing in osteoblast selective connexin 43 deficient mice. PLoS One 2013; 8:e81399. [PMID: 24260576 PMCID: PMC3832658 DOI: 10.1371/journal.pone.0081399] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/22/2013] [Indexed: 12/12/2022] Open
Abstract
Connexin 43 (Cx43) is the most abundant gap junction protein in bone and is required for osteoblastic differentiation and bone homeostasis. During fracture healing, Cx43 is abundantly expressed in osteoblasts and osteocytes, while Cx43 deficiency impairs bone formation and healing. In the present study we selectively deleted Cx43 in the osteoblastic lineage from immature osteoblasts through osteocytes and tested the hypothesis that Cx43 deficiency results in delayed osteoblastic differentiation and impaired restoration of biomechanical properties due to attenuated β-catenin expression relative to wild type littermates. Here we show that Cx43 deficiency results in alterations in the mineralization and remodeling phases of healing. In Cx43 deficient fractures the mineralization phase is marked by delayed expression of osteogenic genes. Additionally, the decrease in the RankL/ Opg ratio, osteoclast number and osteoclast size suggest decreased osteoclast bone resorption and remodeling. These changes in healing result in functional deficits as shown by a decrease in ultimate torque at failure. Consistent with these impairments in healing, β-catenin expression is attenuated in Cx43 deficient fractures at 14 and 21 days, while Sclerostin (Sost) expression, a negative regulator of bone formation is increased in Cx43cKO fractures at 21 days, as is GSK-3β, a key component of the β-catenin proteasomal degradation complex. Furthermore, we show that alterations in healing in Cx43 deficient fractures can be rescued by inhibiting GSK-3β activity using Lithium Chloride (LiCl). Treatment of Cx43 deficient mice with LiCl restores both normal bone formation and mechanical properties relative to LiCl treated WT fractures. This study suggests that Cx43 is a potential therapeutic target to enhance fracture healing and identifies a previously unknown role for Cx43 in regulating β-catenin expression and thus bone formation during fracture repair.
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Guerrero J, Catros S, Derkaoui SM, Lalande C, Siadous R, Bareille R, Thébaud N, Bordenave L, Chassande O, Le Visage C, Letourneur D, Amédée J. Cell interactions between human progenitor-derived endothelial cells and human mesenchymal stem cells in a three-dimensional macroporous polysaccharide-based scaffold promote osteogenesis. Acta Biomater 2013; 9:8200-13. [PMID: 23743130 DOI: 10.1016/j.actbio.2013.05.025] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 05/03/2013] [Accepted: 05/22/2013] [Indexed: 12/12/2022]
Abstract
Several studies have reported the benefits of mesenchymal stem cells (MSCs) for bone tissue engineering. However, vascularization remains one of the main obstacles that must be overcome to reconstruct large bone defects. In vitro prevascularization of the three-dimensional (3-D) constructs using co-cultures of human progenitor-derived endothelial cells (PDECs) with human bone marrow mesenchymal stem cells (HBMSCs) appeared as a potential strategy. However, the crosstalk between the two lineages has been studied in two-dimensional (2-D), but remains unknown in 3-D. The aim of this study is to investigate the cell interactions between PDECs and HBMSCs in a porous matrix composed of polysaccharides. This biodegradable scaffold promotes cell interactions by inducing multicellular aggregates composed of HBMSCs surrounded by PDECs. Cell aggregation contributes to the formation of junctional proteins composed of Connexin43 (Cx43) and VE-cadherin, and an activation of osteoblastic differentiation of HBMSCs stimulated by the presence of PDECs. Inhibition of Cx43 by mimetic peptide 43GAP27 induced a decrease in mRNA levels of Cx43 and all the bone-specific markers. Finally, subcutaneous implantations for 3 and 8 weeks in NOG mice revealed an increase in osteoid formation with the tissue-engineered constructs seeded with HBMSCs/PDECs compared with those loaded with HBMSCs alone. Taking together, these results demonstrate that this 3-D microenvironment favored cell communication, osteogenesis and bone formation.
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Affiliation(s)
- J Guerrero
- Inserm, U1026, Tissue Bioengineering, University Bordeaux Segalen, Bordeaux Cedex 33076, France.
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Hu Y, Chen IP, de Almeida S, Tiziani V, Do Amaral CMR, Gowrishankar K, Passos-Bueno MR, Reichenberger EJ. A novel autosomal recessive GJA1 missense mutation linked to Craniometaphyseal dysplasia. PLoS One 2013; 8:e73576. [PMID: 23951358 PMCID: PMC3741164 DOI: 10.1371/journal.pone.0073576] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 07/04/2013] [Indexed: 11/19/2022] Open
Abstract
Craniometaphyseal dysplasia (CMD) is a rare sclerosing skeletal disorder with progressive hyperostosis of craniofacial bones. CMD can be inherited in an autosomal dominant (AD) trait or occur after de novo mutations in the pyrophosphate transporter ANKH. Although the autosomal recessive (AR) form of CMD had been mapped to 6q21-22 the mutation has been elusive. In this study, we performed whole-exome sequencing for one subject with AR CMD and identified a novel missense mutation (c.716G>A, p.Arg239Gln) in the C-terminus of the gap junction protein alpha-1 (GJA1) coding for connexin 43 (Cx43). We confirmed this mutation in 6 individuals from 3 additional families. The homozygous mutation cosegregated only with affected family members. Connexin 43 is a major component of gap junctions in osteoblasts, osteocytes, osteoclasts and chondrocytes. Gap junctions are responsible for the diffusion of low molecular weight molecules between cells. Mutations in Cx43 cause several dominant and recessive disorders involving developmental abnormalities of bone such as dominant and recessive oculodentodigital dysplasia (ODDD; MIM #164200, 257850) and isolated syndactyly type III (MIM #186100), the characteristic digital anomaly in ODDD. However, characteristic ocular and dental features of ODDD as well as syndactyly are absent in patients with the recessive Arg239Gln Cx43 mutation. Bone remodeling mechanisms disrupted by this novel Cx43 mutation remain to be elucidated.
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Affiliation(s)
- Ying Hu
- Department of Reconstructive Sciences, Center for Regenerative Medicine and Developmental Biology, University of Connecticut Health Center, Farmington, Connecticut, United States of America
| | - I-Ping Chen
- Department of Oral Health and Diagnostic Sciences, University of Connecticut Health Center, Farmington, Connecticut, United States of America
| | - Salome de Almeida
- Medical Genetics Service, Centro Hospitalar de Lisboa, Central, Portugal
| | | | | | - Kalpana Gowrishankar
- Department of Medical Genetics, Kanchi Kamakoti Childs Trust Hospital, Chennai, Tamil Nadu, India
| | | | - Ernst J. Reichenberger
- Department of Reconstructive Sciences, Center for Regenerative Medicine and Developmental Biology, University of Connecticut Health Center, Farmington, Connecticut, United States of America
- * E-mail:
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33
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Ronis MJJ, Sharma N, Vantrease J, Borengasser SJ, Ferguson M, Mercer KE, Cleves MA, Gomez-Acevedo H, Badger TM. Female mice lacking p47phox have altered adipose tissue gene expression and are protected against high fat-induced obesity. Physiol Genomics 2013; 45:351-66. [DOI: 10.1152/physiolgenomics.00148.2012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The current study was designed to determine if the NADPH-oxidase NOX2 plays a role in development of obesity after high fat feeding. Wild-type (WT) mice and mice lacking the essential cytosolic NOX2 system component p47phox (P47KO mice) were fed AIN-93G diets or high-fat diets (HFD) containing 45% fat and 0.5% cholesterol for 13 wk from weaning. Fat mass was increased to a similar degree by HFD in males of both genotypes ( P < 0.05). However, female P47KO-HFD mice had no increase in adiposity or adipocyte size relative to female WT-HFD mice. Resistance to HFD-driven obesity in P47KO females was associated with increased expression of hepatic TFAM and UCP-2 mRNA, markers of mitochondrial number and uncoupling, and increased expression of hepatic mitochondrial respiratory complexes and whole body energy expenditure in response to HFD. Microarray analysis revealed significantly lower expression of mRNA encoding genes linked to energy metabolism, adipocyte differentiation (PPARγ), and fatty acid uptake (CD36, lipoprotein lipase), in fat pads from female P47KO-HFD mice compared with WT-HFD females. Moreover, differentiation of preadipocytes ex vivo was suppressed more by 17β-estradiol in cells from P47KO compared with cells from WT females in conjunction with overexpression of mRNA for Pref-1 ( P < 0.05). HFD mice of both sexes were resistant to the development of hyperglycemia and hepatic steatosis ( P < 0.05) and had reduced serum triglycerides, leptin, and adiponectin relative to WT-HFD mice ( P < 0.05). These data suggest that NOX2 is an important regulator of metabolic homeostasis and diet-induced obesity.
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Affiliation(s)
- Martin J. J. Ronis
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Department of Pharmacology & Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas; and
| | - Neha Sharma
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Jamie Vantrease
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Sarah J. Borengasser
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Department of Pharmacology & Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas; and
| | - Matthew Ferguson
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Kelly E. Mercer
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Mario A. Cleves
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Horacio Gomez-Acevedo
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Department of Pharmacology & Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas; and
| | - Thomas M. Badger
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Department of Physiology & Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
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34
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Plotkin LI, Bellido T. Beyond gap junctions: Connexin43 and bone cell signaling. Bone 2013; 52:157-66. [PMID: 23041511 PMCID: PMC3513515 DOI: 10.1016/j.bone.2012.09.030] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 09/20/2012] [Accepted: 09/25/2012] [Indexed: 12/31/2022]
Abstract
Connexin43 (Cx43) is the most abundant gap junction protein expressed in bone cells and plays a central role in cell-to-cell communication in the skeleton. Findings of the last decade uncovered functions of Cx43 hemichannels expressed on unopposed plasma cell membranes as mediators of the communication between bone cells and their extracellular milieu. Additionally, through its cytoplasmic C-terminus domain, Cx43 serves as a scaffolding protein that associates with structural and signaling molecules leading to regulation of intracellular signaling, independent of channel activity. This perspective discusses the evidence demonstrating that via these diverse mechanisms Cx43 is a key component of the intracellular machinery responsible for signal transduction in bone in response to pharmacologic, hormonal and mechanical stimuli. This advance in the knowledge of the role of connexins increases our understanding of the pathophysiological mechanisms that regulate bone cell function and provides new opportunities to treat bone diseases.
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Affiliation(s)
- Lilian I. Plotkin
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN
| | - Teresita Bellido
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN
- Department of Medicine, Division of Endocrinology, Indiana University School of Medicine, Indianapolis, IN
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35
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Thompson WR, Rubin CT, Rubin J. Mechanical regulation of signaling pathways in bone. Gene 2012; 503:179-93. [PMID: 22575727 DOI: 10.1016/j.gene.2012.04.076] [Citation(s) in RCA: 268] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 03/20/2012] [Accepted: 04/22/2012] [Indexed: 12/21/2022]
Abstract
A wide range of cell types depend on mechanically induced signals to enable appropriate physiological responses. The skeleton is particularly dependent on mechanical information to guide the resident cell population towards adaptation, maintenance and repair. Research at the organ, tissue, cell and molecular levels has improved our understanding of how the skeleton can recognize the functional environment, and how these challenges are translated into cellular information that can site-specifically alter phenotype. This review first considers those cells within the skeleton that are responsive to mechanical signals, including osteoblasts, osteoclasts, osteocytes and osteoprogenitors. This is discussed in light of a range of experimental approaches that can vary parameters such as strain, fluid shear stress, and pressure. The identity of mechanoreceptor candidates is approached, with consideration of integrins, pericellular tethers, focal adhesions, ion channels, cadherins, connexins, and the plasma membrane including caveolar and non-caveolar lipid rafts and their influence on integral signaling protein interactions. Several mechanically regulated intracellular signaling cascades are detailed including activation of kinases (Akt, MAPK, FAK), β-catenin, GTPases, and calcium signaling events. While the interaction of bone cells with their mechanical environment is complex, an understanding of mechanical regulation of bone signaling is crucial to understanding bone physiology, the etiology of diseases such as osteoporosis, and to the development of interventions to improve bone strength.
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Affiliation(s)
- William R Thompson
- Department of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA.
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