1
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Ashimori A, Higashijima F, Ogata T, Sakuma A, Hamada W, Sunada J, Aoki R, Mikuni M, Hayashi K, Wakuta M, Yoshimoto T, Minamoto A, Ko JA, Kimura K. HIF-1α-dependent upregulation of angiogenic factors by mechanical stimulation in retinal pigment epithelial cells. Dis Model Mech 2024; 17:dmm050640. [PMID: 38691000 PMCID: PMC11095633 DOI: 10.1242/dmm.050640] [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: 12/04/2023] [Accepted: 03/22/2024] [Indexed: 05/03/2024] Open
Abstract
Mechanical stimulation as a mimic of drusen formation in the eye increases the expression of angiogenic factors in retinal pigment epithelial (RPE) cells, but the underlying molecular mechanisms remain unclear. We investigated and characterized the effects of mechanical stimulation on the expression of angiogenic factors in RPE cells both in vitro and in a mouse model. Mechanical stimulation increased the expression of vascular endothelial growth factor (VEGF, encoded by VEGFA) and other angiogenesis-related genes in cultured RPE1 cells. The presence of hypoxia-inducible factor 1α (HIF-1α, encoded by HIF1A) was also increased, and both knockdown of HIF-1α and treatment with the HIF-1α inhibitor CAY10585 attenuated the effect of mechanical stimulation on angiogenesis factor gene expression. Signaling by the tyrosine kinase SRC and p38 mitogen-activated protein kinase was involved in HIF-1α activation and consequent angiogenesis-related gene expression induced by mechanical stimulation. Our results suggest that SRC-p38 and HIF-1α signaling are involved in the upregulation of angiogenic factors in RPE cells by mechanical stimulation. Such in vivo suppression of upregulated expression of angiogenesis-related genes by pharmacological inhibitors of HIF-1α suggests a new potential approach to the treatment of age-related macular degeneration.
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Affiliation(s)
- Atsushige Ashimori
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Fumiaki Higashijima
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Tadahiko Ogata
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Ayano Sakuma
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Waka Hamada
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Junki Sunada
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Ren Aoki
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Masanori Mikuni
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Ken'ichiro Hayashi
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Makiko Wakuta
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Takuya Yoshimoto
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
| | - Akira Minamoto
- Department of Ophthalmology and Visual Science, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Ji-Ae Ko
- Department of Ophthalmology and Visual Science, Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan
| | - Kazuhiro Kimura
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube City, Yamaguchi 755-8505, Japan
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2
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Maus I, Dreiner M, Zetzsche S, Metzen F, Ross BC, Mählich D, Koch M, Niehoff A, Wirth B. Osteoclast-specific Plastin 3 knockout in mice fail to develop osteoporosis despite dramatic increased osteoclast resorption activity. JBMR Plus 2024; 8:ziad009. [PMID: 38549711 PMCID: PMC10971598 DOI: 10.1093/jbmrpl/ziad009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 11/11/2023] [Accepted: 11/26/2023] [Indexed: 05/07/2024] Open
Abstract
PLS3 loss-of-function mutations in humans and mice cause X-linked primary osteoporosis. However, it remains largely unknown how PLS3 mutations cause osteoporosis and which function PLS3 plays in bone homeostasis. A recent study showed that ubiquitous Pls3 KO in mice results in osteoporosis. Mainly osteoclasts were impacted in their function However, it has not been proven if osteoclasts are the major cell type affected and responsible for osteoporosis development in ubiquitous Pls3 KO mice. Here, we generated osteoclast-specific Pls3 KO mice. Additionally, we developed a novel polyclonal PLS3 antibody that showed specific PLS3 loss in immunofluorescence staining of osteoclasts in contrast to previously available antibodies against PLS3, which failed to show PLS3 specificity in mouse cells. Moreover, we demonstrate that osteoclast-specific Pls3 KO causes dramatic increase in resorptive activity of osteoclasts in vitro. Despite these findings, osteoclast-specific Pls3 KO in vivo failed to cause any osteoporotic phenotype in mice as proven by micro-CT and three-point bending test. This demonstrates that the pathomechanism of PLS3-associated osteoporosis is highly complex and cannot be reproduced in a system singularly focused on one cell type. Thus, the loss of PLS3 in alternative bone cell types might contributes to the osteoporosis phenotype in ubiquitous Pls3 KO mice.
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Affiliation(s)
- Ilka Maus
- Institute of Human Genetics, University of Cologne, University Hospital of Cologne, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
| | - Maren Dreiner
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, 50933 Cologne, Germany
| | - Sebastian Zetzsche
- Institute of Human Genetics, University of Cologne, University Hospital of Cologne, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
| | - Fabian Metzen
- Medical Faculty, Institute for Dental Research and Oral Musculoskeletal Biology, University of Cologne, 50931 Cologne, Germany
- Medical Faculty, Center for Biochemistry, University of Cologne, 50931 Cologne, Germany
| | - Bryony C Ross
- Institute of Human Genetics, University of Cologne, University Hospital of Cologne, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
| | - Daniela Mählich
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, 50933 Cologne, Germany
| | - Manuel Koch
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
- Medical Faculty, Institute for Dental Research and Oral Musculoskeletal Biology, University of Cologne, 50931 Cologne, Germany
- Medical Faculty, Center for Biochemistry, University of Cologne, 50931 Cologne, Germany
| | - Anja Niehoff
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, 50933 Cologne, Germany
- Faculty of Medicine, Cologne Center for Musculoskeletal Biomechanics (CCMB), University of Cologne, 50931 Cologne, Germany
| | - Brunhilde Wirth
- Institute of Human Genetics, University of Cologne, University Hospital of Cologne, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
- Center for Rare Diseases, University of Cologne, University Hospital of Cologne, 50931 Cologne, Germany
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3
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Zhong W, Pathak JL, Liang Y, Zhytnik L, Pals G, Eekhoff EMW, Bravenboer N, Micha D. The intricate mechanism of PLS3 in bone homeostasis and disease. Front Endocrinol (Lausanne) 2023; 14:1168306. [PMID: 37484945 PMCID: PMC10361617 DOI: 10.3389/fendo.2023.1168306] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 06/19/2023] [Indexed: 07/25/2023] Open
Abstract
Since our discovery in 2013 that genetic defects in PLS3 lead to bone fragility, the mechanistic details of this process have remained obscure. It has been established that PLS3 variants cause syndromic and nonsyndromic osteoporosis as well as osteoarthritis. PLS3 codes for an actin-bundling protein with a broad pattern of expression. As such, it is puzzling how PLS3 specifically leads to bone-related disease presentation. Our review aims to summarize the current state of knowledge regarding the function of PLS3 in the predominant cell types in the bone tissue, the osteocytes, osteoblasts and osteoclasts. This is related to the role of PLS3 in regulating mechanotransduction, calcium regulation, vesicle trafficking, cell differentiation and mineralization as part of the complex bone pathology presented by PLS3 defects. Considering the consequences of PLS3 defects on multiple aspects of bone tissue metabolism, our review motivates the study of its mechanism in bone diseases which can potentially help in the design of suitable therapy.
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Affiliation(s)
- Wenchao Zhong
- Department of Human Genetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Department of Clinical Chemistry, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Amsterdam Movement Sciences, Tissue Function And Regeneration, Amsterdam, Netherlands
- Department of Temporomandibular Joint, Guangdong Engineering Research Center of Oral Restoration and Reconstruction, Guangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative Medicine, Affiliated Stomatology Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Janak L. Pathak
- Department of Temporomandibular Joint, Guangdong Engineering Research Center of Oral Restoration and Reconstruction, Guangzhou Key Laboratory of Basic and Applied Research of Oral Regenerative Medicine, Affiliated Stomatology Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yueting Liang
- Department of Radiation Oncology, Peking University Cancer Hospital & Institute, Beijing, China
- The Second Clinical College, Guangzhou Medical University, Guangzhou, China
| | - Lidiia Zhytnik
- Department of Human Genetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Amsterdam Movement Sciences, Tissue Function And Regeneration, Amsterdam, Netherlands
- Department of Traumatology and Orthopaedics, Institute of Clinical Medicine, The University of Tartu, Tartu, Estonia
| | - Gerard Pals
- Department of Human Genetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Amsterdam Movement Sciences, Tissue Function And Regeneration, Amsterdam, Netherlands
| | - Elisabeth M. W. Eekhoff
- Department Internal Medicine Section Endocrinology and Metabolism, Amsterdam UMC Location Vrije Universiteit Amsterdam, Rare Bone Disease Center, AMS, Amsterdam, Netherlands
- Amsterdam Reproduction and Development Research Institute, Amsterdam, Netherlands
| | - Nathalie Bravenboer
- Department of Clinical Chemistry, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Amsterdam Movement Sciences, Tissue Function And Regeneration, Amsterdam, Netherlands
| | - Dimitra Micha
- Department of Human Genetics, Amsterdam UMC Location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Amsterdam Movement Sciences, Tissue Function And Regeneration, Amsterdam, Netherlands
- Amsterdam Reproduction and Development Research Institute, Amsterdam, Netherlands
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4
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Marques FC, Boaretti D, Walle M, Scheuren AC, Schulte FA, Müller R. Mechanostat parameters estimated from time-lapsed in vivo micro-computed tomography data of mechanically driven bone adaptation are logarithmically dependent on loading frequency. Front Bioeng Biotechnol 2023; 11:1140673. [PMID: 37113673 PMCID: PMC10126906 DOI: 10.3389/fbioe.2023.1140673] [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: 01/09/2023] [Accepted: 03/27/2023] [Indexed: 04/29/2023] Open
Abstract
Mechanical loading is a key factor governing bone adaptation. Both preclinical and clinical studies have demonstrated its effects on bone tissue, which were also notably predicted in the mechanostat theory. Indeed, existing methods to quantify bone mechanoregulation have successfully associated the frequency of (re)modeling events with local mechanical signals, combining time-lapsed in vivo micro-computed tomography (micro-CT) imaging and micro-finite element (micro-FE) analysis. However, a correlation between the local surface velocity of (re)modeling events and mechanical signals has not been shown. As many degenerative bone diseases have also been linked to impaired bone (re)modeling, this relationship could provide an advantage in detecting the effects of such conditions and advance our understanding of the underlying mechanisms. Therefore, in this study, we introduce a novel method to estimate (re)modeling velocity curves from time-lapsed in vivo mouse caudal vertebrae data under static and cyclic mechanical loading. These curves can be fitted with piecewise linear functions as proposed in the mechanostat theory. Accordingly, new (re)modeling parameters can be derived from such data, including formation saturation levels, resorption velocity moduli, and (re)modeling thresholds. Our results revealed that the norm of the gradient of strain energy density yielded the highest accuracy in quantifying mechanoregulation data using micro-finite element analysis with homogeneous material properties, while effective strain was the best predictor for micro-finite element analysis with heterogeneous material properties. Furthermore, (re)modeling velocity curves could be accurately described with piecewise linear and hyperbola functions (root mean square error below 0.2 µm/day for weekly analysis), and several (re)modeling parameters determined from these curves followed a logarithmic relationship with loading frequency. Crucially, (re)modeling velocity curves and derived parameters could detect differences in mechanically driven bone adaptation, which complemented previous results showing a logarithmic relationship between loading frequency and net change in bone volume fraction over 4 weeks. Together, we expect this data to support the calibration of in silico models of bone adaptation and the characterization of the effects of mechanical loading and pharmaceutical treatment interventions in vivo.
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5
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Paul GR, Vallaster P, Rüegg M, Scheuren AC, Tourolle DC, Kuhn GA, Wehrle E, Müller R. Tissue-Level Regeneration and Remodeling Dynamics are Driven by Mechanical Stimuli in the Microenvironment in a Post-Bridging Loaded Femur Defect Healing Model in Mice. Front Cell Dev Biol 2022; 10:856204. [PMID: 35686050 PMCID: PMC9171432 DOI: 10.3389/fcell.2022.856204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 04/07/2022] [Indexed: 11/30/2022] Open
Abstract
Bone healing and remodeling are mechanically driven processes. While the generalized response to mechanical stimulation in bone is well-understood, much less is known about the mechanobiology-regulating tissue-scale bone formation and resorption during the reparative and remodeling phases of fracture healing. In this study, we combined computational approaches in the form of finite element analysis and experimental approaches by using a loaded femoral defect model in mice to investigate the role of mechanical stimulation in the microenvironment of bone. Specifically, we used longitudinal micro-computed tomography to observe temporal changes in bone at different densities and micro-finite element analysis to map the mechanics of the microenvironment to tissue-scale formation, quiescence (no change in bone presence between time points), and resorption dynamics in the late reparative and remodeling phases (post bridging). Increasing levels of effective strain led to increasing conditional probability of bone formation, while decreasing levels of effective strain led to increasing probability of bone resorption. In addition, the analysis of mineralization dynamics showed both a temporal and effective strain level-dependent behavior. A logarithmic-like response was displayed, where the conditional probability of bone formation or resorption increased rapidly and plateaued or fell rapidly and plateaued as mechanical strain increased.
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6
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Flow Rate Prediction for a Semi-permeable Membrane at Low Reynolds Number in a Circular Pipe. Transp Porous Media 2021. [DOI: 10.1007/s11242-021-01716-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractA concise and accurate prediction method is required for membrane permeability in chemical engineering and biological fields. As a preliminary study on this topic, we propose the concentration polarization model (CPM) of the permeate flux and flow rate under dominant effects of viscosity and solute diffusion. In this model, concentration polarization is incorporated for the solution flow through a semi-permeable membrane (i.e., permeable for solvent but not for solute) in a circular pipe. The effect of the concentration polarization on the flow field in a circular pipe under a viscous-dominant condition (i.e., at a low Reynolds number) is discussed by comparing the CPM with the numerical simulation results and infinitesimal Péclet number model (IPM) for the membrane permeability, strength of the osmotic pressure, and Péclet number. The CPM and IPM are confirmed to be a reasonable extension of the model for a pure fluid, which was proposed previously. The application range of the IPM is narrow because the advection of the solute concentration is not considered, whereas the CPM demonstrates superior applicability in a wide range of parameters, including the permeability coefficient, strength of the osmotic pressure, and Péclet number. This suggests the necessity for considering concentration polarization. Although the mathematical expression of the CPM is more complex than that of the IPM, the CPM exhibits a potential to accurately predict the permeability parameters for a condition in which a large permeate flux and osmotic pressure occur.
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7
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Ichimura T, Kakizuka T, Horikawa K, Seiriki K, Kasai A, Hashimoto H, Fujita K, Watanabe TM, Nagai T. Exploring rare cellular activity in more than one million cells by a transscale scope. Sci Rep 2021; 11:16539. [PMID: 34400683 PMCID: PMC8368064 DOI: 10.1038/s41598-021-95930-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 08/03/2021] [Indexed: 02/07/2023] Open
Abstract
In many phenomena of biological systems, not a majority, but a minority of cells act on the entire multicellular system causing drastic changes in the system properties. To understand the mechanisms underlying such phenomena, it is essential to observe the spatiotemporal dynamics of a huge population of cells at sub-cellular resolution, which is difficult with conventional tools such as microscopy and flow cytometry. Here, we describe an imaging system named AMATERAS that enables optical imaging with an over-one-centimeter field-of-view and a-few-micrometer spatial resolution. This trans-scale-scope has a simple configuration, composed of a low-power lens for machine vision and a hundred-megapixel image sensor. We demonstrated its high cell-throughput, capable of simultaneously observing more than one million cells. We applied it to dynamic imaging of calcium ions in HeLa cells and cyclic-adenosine-monophosphate in Dictyostelium discoideum, and successfully detected less than 0.01% of rare cells and observed multicellular events induced by these cells.
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Affiliation(s)
- T Ichimura
- Transdimensional Life Imaging Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan.
- PRESTO, Japan Science and Technology Agency, Tokyo, 113-0033, Japan.
| | - T Kakizuka
- Transdimensional Life Imaging Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - K Horikawa
- Department of Optical Imaging, Advanced Research Promotion Center, Tokushima University, Kuramoto-cho 3-18-15, Tokushima, Tokushima, 770-8503, Japan
| | - K Seiriki
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Yamadaoka 1-6, Suita, Osaka, 565-0871, Japan
| | - A Kasai
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Yamadaoka 1-6, Suita, Osaka, 565-0871, Japan
| | - H Hashimoto
- Transdimensional Life Imaging Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
- Laboratory of Molecular Neuropharmacology, Graduate School of Pharmaceutical Sciences, Osaka University, Yamadaoka 1-6, Suita, Osaka, 565-0871, Japan
- Institute for Transdisciplinary Graduate Degree Programs, Osaka University, Yamadaoka 1-1, Suita, Osaka, 565-0871, Japan
| | - K Fujita
- Transdimensional Life Imaging Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
- Department of Applied Physics, Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan
| | - T M Watanabe
- Laboratory for Comprehensive Bioimaging, RIKEN Center for Biosystems Dynamics Research (BDR), Minatomachi-minami 2-2-3, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
- Department of Stem Cell Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima, 734-8553, Japan
| | - T Nagai
- Transdimensional Life Imaging Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565-0871, Japan.
- SANKEN (The Institute of Scientific and Industrial Research), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka, 567-0047, Japan.
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8
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Iskander A, Bilgi C, Naftalovich R, Hacihaliloglu I, Berkman T, Naftalovich D, Pahlevan N. The Rheology of the Carotid Sinus: A Path Toward Bioinspired Intervention. Front Bioeng Biotechnol 2021; 9:678048. [PMID: 34178967 PMCID: PMC8222608 DOI: 10.3389/fbioe.2021.678048] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/05/2021] [Indexed: 11/30/2022] Open
Abstract
The association between blood viscosity and pathological conditions involving a number of organ systems is well known. However, how the body measures and maintains appropriate blood viscosity is not well-described. The literature endorsing the function of the carotid sinus as a site of baroreception can be traced back to some of the earliest descriptions of digital pressure on the neck producing a drop in blood delivery to the brain. For the last 30 years, improved computational fluid dynamic (CFD) simulations of blood flow within the carotid sinus have demonstrated a more nuanced understanding of the changes in the region as it relates to changes in conventional metrics of cardiovascular function, including blood pressure. We suggest that the unique flow patterns within the carotid sinus may make it an ideal site to transduce flow data that can, in turn, enable real-time measurement of blood viscosity. The recent characterization of the PIEZO receptor family in the sinus vessel wall may provide a biological basis for this characterization. When coupled with other biomarkers of cardiovascular performance and descriptions of the blood rheology unique to the sinus region, this represents a novel venue for bioinspired design that may enable end-users to manipulate and optimize blood flow.
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Affiliation(s)
- Andrew Iskander
- Department of Anesthesiology, Westchester Medical Center, New York Medical College, Valhalla, NY, United States
| | - Coskun Bilgi
- Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA, United States
| | - Rotem Naftalovich
- Department of Anesthesiology, New Jersey Medical School, University Hospital, Rutgers University, Newark, NJ, United States.,Medical Corps of the U.S. Army, U.S. Army Medical Department, Fort Sam Houston, San Antonio, TX, United States
| | - Ilker Hacihaliloglu
- Department of Biomedical Engineering, Rutgers School of Engineering, Rutgers University, Piscataway, NJ, United States
| | - Tolga Berkman
- Department of Anesthesiology, New Jersey Medical School, University Hospital, Rutgers University, Newark, NJ, United States
| | - Daniel Naftalovich
- Department of Computational and Mathematical Sciences, California Institute of Technology, Pasadena, CA, United States.,Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Niema Pahlevan
- Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA, United States.,Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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9
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Lang C, Conrad L, Iber D. Organ-Specific Branching Morphogenesis. Front Cell Dev Biol 2021; 9:671402. [PMID: 34150767 PMCID: PMC8212048 DOI: 10.3389/fcell.2021.671402] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 05/06/2021] [Indexed: 01/09/2023] Open
Abstract
A common developmental process, called branching morphogenesis, generates the epithelial trees in a variety of organs, including the lungs, kidneys, and glands. How branching morphogenesis can create epithelial architectures of very different shapes and functions remains elusive. In this review, we compare branching morphogenesis and its regulation in lungs and kidneys and discuss the role of signaling pathways, the mesenchyme, the extracellular matrix, and the cytoskeleton as potential organ-specific determinants of branch position, orientation, and shape. Identifying the determinants of branch and organ shape and their adaptation in different organs may reveal how a highly conserved developmental process can be adapted to different structural and functional frameworks and should provide important insights into epithelial morphogenesis and developmental disorders.
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Affiliation(s)
- Christine Lang
- Department of Biosystems, Science and Engineering, ETH Zürich, Basel, Switzerland.,Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Lisa Conrad
- Department of Biosystems, Science and Engineering, ETH Zürich, Basel, Switzerland.,Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Dagmar Iber
- Department of Biosystems, Science and Engineering, ETH Zürich, Basel, Switzerland.,Swiss Institute of Bioinformatics, Basel, Switzerland
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10
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Plastin 3 in health and disease: a matter of balance. Cell Mol Life Sci 2021; 78:5275-5301. [PMID: 34023917 PMCID: PMC8257523 DOI: 10.1007/s00018-021-03843-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/06/2021] [Accepted: 04/20/2021] [Indexed: 02/06/2023]
Abstract
For a long time, PLS3 (plastin 3, also known as T-plastin or fimbrin) has been considered a rather inconspicuous protein, involved in F-actin-binding and -bundling. However, in recent years, a plethora of discoveries have turned PLS3 into a highly interesting protein involved in many cellular processes, signaling pathways, and diseases. PLS3 is localized on the X-chromosome, but shows sex-specific, inter-individual and tissue-specific expression variability pointing towards skewed X-inactivation. PLS3 is expressed in all solid tissues but usually not in hematopoietic cells. When escaping X-inactivation, PLS3 triggers a plethora of different types of cancers. Elevated PLS3 levels are considered a prognostic biomarker for cancer and refractory response to therapies. When it is knocked out or mutated in humans and mice, it causes osteoporosis with bone fractures; it is the only protein involved in actin dynamics responsible for osteoporosis. Instead, when PLS3 is upregulated, it acts as a highly protective SMN-independent modifier in spinal muscular atrophy (SMA). Here, it seems to counteract reduced F-actin levels by restoring impaired endocytosis and disturbed calcium homeostasis caused by reduced SMN levels. In contrast, an upregulation of PLS3 on wild-type level might cause osteoarthritis. This emphasizes that the amount of PLS3 in our cells must be precisely balanced; both too much and too little can be detrimental. Actin-dynamics, regulated by PLS3 among others, are crucial in a lot of cellular processes including endocytosis, cell migration, axonal growth, neurotransmission, translation, and others. Also, PLS3 levels influence the infection with different bacteria, mycosis, and other pathogens.
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11
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Conrad L, Runser SVM, Fernando Gómez H, Lang CM, Dumond MS, Sapala A, Schaumann L, Michos O, Vetter R, Iber D. The biomechanical basis of biased epithelial tube elongation in lung and kidney development. Development 2021; 148:261770. [PMID: 33946098 PMCID: PMC8126414 DOI: 10.1242/dev.194209] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 03/16/2021] [Indexed: 01/16/2023]
Abstract
During lung development, epithelial branches expand preferentially in a longitudinal direction. This bias in outgrowth has been linked to a bias in cell shape and in the cell division plane. How this bias arises is unknown. Here, we show that biased epithelial outgrowth occurs independent of the surrounding mesenchyme, of preferential turnover of the extracellular matrix at the bud tips and of FGF signalling. There is also no evidence for actin-rich filopodia at the bud tips. Rather, we find epithelial tubes to be collapsed during early lung and kidney development, and we observe fluid flow in the narrow tubes. By simulating the measured fluid flow inside segmented narrow epithelial tubes, we show that the shear stress levels on the apical surface are sufficient to explain the reported bias in cell shape and outgrowth. We use a cell-based vertex model to confirm that apical shear forces, unlike constricting forces, can give rise to both the observed bias in cell shapes and tube elongation. We conclude that shear stress may be a more general driver of biased tube elongation beyond its established role in angiogenesis. This article has an associated 'The people behind the papers' interview.
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Affiliation(s)
- Lisa Conrad
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Steve Vincent Maurice Runser
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Harold Fernando Gómez
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Christine Michaela Lang
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Mathilde Sabine Dumond
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Aleksandra Sapala
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Laura Schaumann
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Odyssé Michos
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Roman Vetter
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
| | - Dagmar Iber
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Mattenstraße 26, 4058 Basel, Switzerland.,Swiss Institute of Bioinformatics (SIB), Mattenstraße 26, 4058 Basel, Switzerland
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12
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Abstract
Branching morphogenesis generates epithelial trees which facilitate gas exchange, filtering, as well as secretion processes with their large surface to volume ratio. In this review, we focus on the developmental mechanisms that control the early stages of lung branching morphogenesis. Lung branching morphogenesis involves the stereotypic, recurrent definition of new branch points, subsequent epithelial budding, and lung tube elongation. We discuss current models and experimental evidence for each of these steps. Finally, we discuss the role of the mesenchyme in determining the organ-specific shape.
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Affiliation(s)
- Dagmar Iber
- Department of Biosystems, Science and Engineering (D-BSSE), ETH Zurich, Basel, Switzerland; Swiss Institute of Bioinformatics (SIB), Basel, Switzerland.
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13
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Maestroni L, Read P, Bishop C, Papadopoulos K, Suchomel TJ, Comfort P, Turner A. The Benefits of Strength Training on Musculoskeletal System Health: Practical Applications for Interdisciplinary Care. Sports Med 2021; 50:1431-1450. [PMID: 32564299 DOI: 10.1007/s40279-020-01309-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Global health organizations have provided recommendations regarding exercise for the general population. Strength training has been included in several position statements due to its multi-systemic benefits. In this narrative review, we examine the available literature, first explaining how specific mechanical loading is converted into positive cellular responses. Secondly, benefits related to specific musculoskeletal tissues are discussed, with practical applications and training programmes clearly outlined for both common musculoskeletal disorders and primary prevention strategies.
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Affiliation(s)
- Luca Maestroni
- Smuoviti, Viale Giulio Cesare, 29, 24121, Bergamo, BG, Italy. .,StudioErre, Via della Badia, 18, 25127, Brescia, BS, Italy. .,London Sport Institute, School of Science and Technology, Middlesex University, Greenlands Lane, London, UK.
| | - Paul Read
- Athlete Health and Performance Research Center, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.,School of Sport and Exercise, University of Gloucestershire, Gloucester, UK
| | - Chris Bishop
- London Sport Institute, School of Science and Technology, Middlesex University, Greenlands Lane, London, UK
| | - Konstantinos Papadopoulos
- London Sport Institute, School of Science and Technology, Middlesex University, Greenlands Lane, London, UK
| | - Timothy J Suchomel
- Department of Human Movement Sciences, Carroll University, Waukesha, WI, USA.,Directorate of Psychology and Sport, University of Salford, Frederick Road, Salford, Greater Manchester, UK
| | - Paul Comfort
- Directorate of Psychology and Sport, University of Salford, Frederick Road, Salford, Greater Manchester, UK.,Institute for Sport, Physical Activity and Leisure, Carnegie School of Sport, Leeds Beckett University, Leeds, UK.,Centre for Exercise and Sport Science Research, Edith Cowan University, Joondalup, Australia
| | - Anthony Turner
- London Sport Institute, School of Science and Technology, Middlesex University, Greenlands Lane, London, UK
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14
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Okawara H, Arai Y, Matsuno H, Marcián P, Borák L, Aoki K, Wakabayashi N. Effect of load-induced local mechanical strain on peri-implant bone cell activity related to bone resorption and formation in mice: An analysis of histology and strain distributions. J Mech Behav Biomed Mater 2021; 116:104370. [PMID: 33545417 DOI: 10.1016/j.jmbbm.2021.104370] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 02/07/2023]
Abstract
The purpose of this study was to investigate the effect of load-induced local mechanical strain on bone cell activity of peri-implant bone in mice. Titanium implants were placed in the maxillae of 13-week-old male C57BL/6J mice and subjected to intermittent 0.15 N, 0.3 N, or 0.6 N loads for 30 min/day for 6 days. The animals were sacrificed 2 days after the final loading. Unloaded mice were used as controls. An animal-specific three-dimensional finite element model was constructed based on morphological data retrieved from in vivo microfocus computed tomography for each mouse to calculate the mechanical strain distribution. Strain distribution images were overlaid on corresponding histological images of the same site in the same animal. The buccal cervical region of the peri-implant bone was predetermined as the region of interest (ROI). Each ROI was divided by four strain intensity levels: 0-20 με, 20-60 με, 60-100 με, and ≥100 με, and the bone histomorphometric parameters were analyzed by the total area of each strain range for all loaded samples. The distance between the calcified front and calcein labeling as a parameter representing the mineral apposition rate was significantly greater in the areas with strain intensity ≥100 με than in the area with strain intensity <100 με, suggesting that the bone formation activity of osteoblasts was locally enhanced by a higher mechanical strain. However, the shrunken osteocytes and the empty osteocyte lacunae were significantly lower in the highest strain area, suggesting that osteoclastogenesis was more retarded in higher strain areas than in lower strain areas. The histomorphometric parameters were not affected geometrically in the unloaded animals, suggesting that the load-induced mechanical strain caused differences in the histomorphometric parameters. Our findings support the hypothesis that bone cell activity related to bone resorption and formation is local strain-dependent on implant loading.
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Affiliation(s)
- Hisami Okawara
- Removable Partial Prosthodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Yuki Arai
- Removable Partial Prosthodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Hitomi Matsuno
- Removable Partial Prosthodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Petr Marcián
- Institute of Solid Mechanics, Mechatronics and Biomechanics, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2896/2, 616 69, Brno, Czech Republic
| | - Libor Borák
- Institute of Solid Mechanics, Mechatronics and Biomechanics, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2896/2, 616 69, Brno, Czech Republic
| | - Kazuhiro Aoki
- Department of Basic Oral Health Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan
| | - Noriyuki Wakabayashi
- Removable Partial Prosthodontics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8549, Japan.
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15
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Scheuren AC, Vallaster P, Kuhn GA, Paul GR, Malhotra A, Kameo Y, Müller R. Mechano-Regulation of Trabecular Bone Adaptation Is Controlled by the Local in vivo Environment and Logarithmically Dependent on Loading Frequency. Front Bioeng Biotechnol 2020; 8:566346. [PMID: 33154964 PMCID: PMC7591723 DOI: 10.3389/fbioe.2020.566346] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 09/23/2020] [Indexed: 12/23/2022] Open
Abstract
It is well-established that cyclic, but not static, mechanical loading has anabolic effects on bone. However, the function describing the relationship between the loading frequency and the amount of bone adaptation remains unclear. Using a combined experimental and computational approach, this study aimed to investigate whether trabecular bone mechano-regulation is controlled by mechanical signals in the local in vivo environment and dependent on loading frequency. Specifically, by combining in vivo micro-computed tomography (micro-CT) imaging with micro-finite element (micro-FE) analysis, we monitored the changes in microstructural as well as the mechanical in vivo environment [strain energy density (SED) and SED gradient] of mouse caudal vertebrae over 4 weeks of either cyclic loading at varying frequencies of 2, 5, or 10 Hz, respectively, or static loading. Higher values of SED and SED gradient on the local tissue level led to an increased probability of trabecular bone formation and a decreased probability of trabecular bone resorption. In all loading groups, the SED gradient was superior in the determination of local bone formation and resorption events as compared to SED. Cyclic loading induced positive net (re)modeling rates when compared to sham and static loading, mainly due to an increase in mineralizing surface and a decrease in eroded surface. Consequently, bone volume fraction increased over time in 2, 5, and 10 Hz (+15%, +21% and +24%, p ≤ 0.0001), while static loading led to a decrease in bone volume fraction (-9%, p ≤ 0.001). Furthermore, regression analysis revealed a logarithmic relationship between loading frequency and the net change in bone volume fraction over the 4 week observation period (R 2 = 0.74). In conclusion, these results suggest that trabecular bone adaptation is regulated by mechanical signals in the local in vivo environment and furthermore, that mechano-regulation is logarithmically dependent on loading frequency with frequencies below a certain threshold having catabolic effects, and those above anabolic effects. This study thereby provides valuable insights toward a better understanding of the mechanical signals influencing trabecular bone formation and resorption in the local in vivo environment.
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Affiliation(s)
| | - Paul Vallaster
- Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Gisela A. Kuhn
- Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Graeme R. Paul
- Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Angad Malhotra
- Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
| | - Yoshitaka Kameo
- Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Ralph Müller
- Institute for Biomechanics, ETH Zurich, Zurich, Switzerland
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16
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Dallas SL, Moore DS. Using confocal imaging approaches to understand the structure and function of osteocytes and the lacunocanalicular network. Bone 2020; 138:115463. [PMID: 32512167 PMCID: PMC7423610 DOI: 10.1016/j.bone.2020.115463] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 05/29/2020] [Indexed: 02/07/2023]
Abstract
Although overlooked in the past, osteocytes have come to the forefront of skeletal biology and are now recognized as a key cell type that integrates hormonal, mechanical and other signals to control bone mass through regulation of both osteoblast and osteoclast activity. With the surge of recent interest in osteocytes as bone regulatory cells and the discovery that they also function as endocrine regulators of phosphate homeostasis, there has been renewed interest in understanding the structure and function of these unique and relatively inaccessible cells. Osteocytes are embedded within the mineralized bone matrix and are housed within a complex lacunocanalicular system which connects them with the circulation and with other organ systems. This has presented unique challenges for imaging these cells. This review summarizes recent advances in confocal imaging approaches for visualizing osteocytes and their lacunocanalicular networks in both living and fixed bone specimens and discusses how computational approaches can be combined with live and fixed cell imaging techniques to generate quantitative outputs and predictive models. The integration of advanced imaging with computational approaches promises to lead to a more in depth understanding of the structure and function of osteocyte networks and the lacunocanalicular system in the healthy and aging state as well as in pathological conditions in bone.
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Affiliation(s)
- Sarah L Dallas
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri Kansas City, Kansas City, MO 64108, United States of America.
| | - David S Moore
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri Kansas City, Kansas City, MO 64108, United States of America
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17
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Sato T, Verma S, Andrade CDC, Omeara M, Campbell N, Wang JS, Cetinbas M, Lang A, Ausk BJ, Brooks DJ, Sadreyev RI, Kronenberg HM, Lagares D, Uda Y, Pajevic PD, Bouxsein ML, Gross TS, Wein MN. A FAK/HDAC5 signaling axis controls osteocyte mechanotransduction. Nat Commun 2020; 11:3282. [PMID: 32612176 PMCID: PMC7329900 DOI: 10.1038/s41467-020-17099-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 06/11/2020] [Indexed: 11/13/2022] Open
Abstract
Osteocytes, cells ensconced within mineralized bone matrix, are the primary skeletal mechanosensors. Osteocytes sense mechanical cues by changes in fluid flow shear stress (FFSS) across their dendritic projections. Loading-induced reductions of osteocytic Sclerostin (encoded by Sost) expression stimulates new bone formation. However, the molecular steps linking mechanotransduction and Sost suppression remain unknown. Here, we report that class IIa histone deacetylases (HDAC4 and HDAC5) are required for loading-induced Sost suppression and bone formation. FFSS signaling drives class IIa HDAC nuclear translocation through a signaling pathway involving direct HDAC5 tyrosine 642 phosphorylation by focal adhesion kinase (FAK), a HDAC5 post-translational modification that controls its subcellular localization. Osteocyte cell adhesion supports FAK tyrosine phosphorylation, and FFSS triggers FAK dephosphorylation. Pharmacologic FAK catalytic inhibition reduces Sost mRNA expression in vitro and in vivo. These studies demonstrate a role for HDAC5 as a transducer of matrix-derived cues to regulate cell type-specific gene expression.
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Affiliation(s)
- Tadatoshi Sato
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Shiv Verma
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | | | - Maureen Omeara
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Nia Campbell
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Jialiang S. Wang
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Murat Cetinbas
- Department of Molecular Biology and Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Audrey Lang
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Brandon J. Ausk
- 0000000122986657grid.34477.33Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, WA USA
| | - Daniel J. Brooks
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA ,Center for Advanced Orthopaedic Studies, Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA USA
| | - Ruslan I. Sadreyev
- Department of Molecular Biology and Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Henry M. Kronenberg
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - David Lagares
- Center for Immunology and Inflammatory Diseases, Fibrosis Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Yuhei Uda
- 0000 0004 1936 7558grid.189504.1Translational Dental Medicine, Henry M. Goldman School of Dental Medicine, Boston University, Boston, MA USA
| | - Paola Divieti Pajevic
- 0000 0004 1936 7558grid.189504.1Translational Dental Medicine, Henry M. Goldman School of Dental Medicine, Boston University, Boston, MA USA
| | - Mary L. Bouxsein
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA ,Center for Advanced Orthopaedic Studies, Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA USA
| | - Ted S. Gross
- 0000000122986657grid.34477.33Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, WA USA
| | - Marc N. Wein
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA ,grid.66859.34Broad Institute of Harvard and MIT, Cambridge, MA USA
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18
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Griffith CM, Huang SA, Cho C, Khare TM, Rich M, Lee GH, Ligler FS, Diekman BO, Polacheck WJ. Microfluidics for the study of mechanotransduction. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2020; 53:224004. [PMID: 33840837 PMCID: PMC8034607 DOI: 10.1088/1361-6463/ab78d4] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Mechanical forces regulate a diverse set of biological processes at cellular, tissue, and organismal length scales. Investigating the cellular and molecular mechanisms that underlie the conversion of mechanical forces to biological responses is challenged by limitations of traditional animal models and in vitro cell culture, including poor control over applied force and highly artificial cell culture environments. Recent advances in fabrication methods and material processing have enabled the development of microfluidic platforms that provide precise control over the mechanical microenvironment of cultured cells. These devices and systems have proven to be powerful for uncovering and defining mechanisms of mechanotransduction. In this review, we first give an overview of the main mechanotransduction pathways that function at sites of cell adhesion, many of which have been investigated with microfluidics. We then discuss how distinct microfluidic fabrication methods can be harnessed to gain biological insight, with description of both monolithic and replica molding approaches. Finally, we present examples of how microfluidics can be used to apply both solid forces (substrate mechanics, strain, and compression) and fluid forces (luminal, interstitial) to cells. Throughout the review, we emphasize the advantages and disadvantages of different fabrication methods and applications of force in order to provide perspective to investigators looking to apply forces to cells in their own research.
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Affiliation(s)
- Christian M Griffith
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC and North Carolina State University, Raleigh, NC
| | - Stephanie A Huang
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC and North Carolina State University, Raleigh, NC
| | - Crescentia Cho
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC and North Carolina State University, Raleigh, NC
| | - Tanmay M Khare
- Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC
| | - Matthew Rich
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC and North Carolina State University, Raleigh, NC
- Thurston Arthritis Research Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC
| | - Gi-Hun Lee
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC and North Carolina State University, Raleigh, NC
| | - Frances S Ligler
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC and North Carolina State University, Raleigh, NC
| | - Brian O Diekman
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC and North Carolina State University, Raleigh, NC
- Thurston Arthritis Research Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC
| | - William J Polacheck
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC and North Carolina State University, Raleigh, NC
- McAllister Heart Institute, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC
- Cancer Cell Biology Program, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC
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19
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Pradhan S, Banda OA, Farino CJ, Sperduto JL, Keller KA, Taitano R, Slater JH. Biofabrication Strategies and Engineered In Vitro Systems for Vascular Mechanobiology. Adv Healthc Mater 2020; 9:e1901255. [PMID: 32100473 PMCID: PMC8579513 DOI: 10.1002/adhm.201901255] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 01/24/2020] [Indexed: 12/17/2022]
Abstract
The vascular system is integral for maintaining organ-specific functions and homeostasis. Dysregulation in vascular architecture and function can lead to various chronic or acute disorders. Investigation of the role of the vascular system in health and disease has been accelerated through the development of tissue-engineered constructs and microphysiological on-chip platforms. These in vitro systems permit studies of biochemical regulation of vascular networks and parenchymal tissue and provide mechanistic insights into the biophysical and hemodynamic forces acting in organ-specific niches. Detailed understanding of these forces and the mechanotransductory pathways involved is necessary to develop preventative and therapeutic strategies targeting the vascular system. This review describes vascular structure and function, the role of hemodynamic forces in maintaining vascular homeostasis, and measurement approaches for cell and tissue level mechanical properties influencing vascular phenomena. State-of-the-art techniques for fabricating in vitro microvascular systems, with varying degrees of biological and engineering complexity, are summarized. Finally, the role of vascular mechanobiology in organ-specific niches and pathophysiological states, and efforts to recapitulate these events using in vitro microphysiological systems, are explored. It is hoped that this review will help readers appreciate the important, but understudied, role of vascular-parenchymal mechanotransduction in health and disease toward developing mechanotherapeutics for treatment strategies.
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Affiliation(s)
- Shantanu Pradhan
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - Omar A. Banda
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - Cindy J. Farino
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - John L. Sperduto
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - Keely A. Keller
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - Ryan Taitano
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - John H. Slater
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
- Department of Materials Science and Engineering, University of Delaware, 201 DuPont Hall, Newark, DE 19716, USA
- Delaware Biotechnology Institute, 15 Innovation Way, Newark, DE 19711, USA
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20
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Verschuren EHJ, Rigalli JP, Castenmiller C, Rohrbach MU, Bindels RJM, Peters DJM, Arjona FJ, Hoenderop JGJ. Pannexin-1 mediates fluid shear stress-sensitive purinergic signaling and cyst growth in polycystic kidney disease. FASEB J 2020; 34:6382-6398. [PMID: 32159259 DOI: 10.1096/fj.201902901r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/07/2020] [Accepted: 03/01/2020] [Indexed: 12/16/2022]
Abstract
Tubular ATP release is regulated by mechanosensation of fluid shear stress (FSS). Polycystin-1/polycystin-2 (PC1/PC2) functions as a mechanosensory complex in the kidney. Extracellular ATP is implicated in polycystic kidney disease (PKD), where PC1/PC2 is dysfunctional. This study aims to provide new insights into the ATP signaling under physiological conditions and PKD. Microfluidics, pharmacologic inhibition, and loss-of-function approaches were combined to assess the ATP release in mouse distal convoluted tubule 15 (mDCT15) cells. Kidney-specific Pkd1 knockout mice (iKsp-Pkd1-/- ) and zebrafish pkd2 morphants (pkd2-MO) were as models for PKD. FSS-exposed mDCT15 cells displayed increased ATP release. Pannexin-1 inhibition and knockout decreased FSS-modulated ATP release. In iKsp-Pkd1-/- mice, elevated renal pannexin-1 mRNA expression and urinary ATP were observed. In Pkd1-/- mDCT15 cells, elevated ATP release was observed upon the FSS mechanosensation. In these cells, increased pannexin-1 mRNA expression was observed. Importantly, pannexin-1 inhibition in pkd2-MO decreased the renal cyst growth. Our results demonstrate that pannexin-1 channels mediate ATP release into the tubular lumen due to pro-urinary flow. We present pannexin-1 as novel therapeutic target to prevent the renal cyst growth in PKD.
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Affiliation(s)
- Eric H J Verschuren
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Juan P Rigalli
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Charlotte Castenmiller
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Meike U Rohrbach
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - René J M Bindels
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Dorien J M Peters
- Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Francisco J Arjona
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Joost G J Hoenderop
- Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
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21
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Besio R, Chow CW, Tonelli F, Marini JC, Forlino A. Bone biology: insights from osteogenesis imperfecta and related rare fragility syndromes. FEBS J 2019; 286:3033-3056. [PMID: 31220415 PMCID: PMC7384889 DOI: 10.1111/febs.14963] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 05/06/2019] [Accepted: 06/14/2019] [Indexed: 12/11/2022]
Abstract
The limited accessibility of bone and its mineralized nature have restricted deep investigation of its biology. Recent breakthroughs in identification of mutant proteins affecting bone tissue homeostasis in rare skeletal diseases have revealed novel pathways involved in skeletal development and maintenance. The characterization of new dominant, recessive and X-linked forms of the rare brittle bone disease osteogenesis imperfecta (OI) and other OI-related bone fragility disorders was a key player in this advance. The development of in vitro models for these diseases along with the generation and characterization of murine and zebrafish models contributed to dissecting previously unknown pathways. Here, we describe the most recent advances in the understanding of processes involved in abnormal bone mineralization, collagen processing and osteoblast function, as illustrated by the characterization of new causative genes for OI and OI-related fragility syndromes. The coordinated role of the integral membrane protein BRIL and of the secreted protein PEDF in modulating bone mineralization as well as the function and cross-talk of the collagen-specific chaperones HSP47 and FKBP65 in collagen processing and secretion are discussed. We address the significance of WNT ligand, the importance of maintaining endoplasmic reticulum membrane potential and of regulating intramembrane proteolysis in osteoblast homeostasis. Moreover, we also examine the relevance of the cytoskeletal protein plastin-3 and of the nucleotidyltransferase FAM46A. Thanks to these advances, new targets for the development of novel therapies for currently incurable rare bone diseases have been and, likely, will be identified, supporting the important role of basic science for translational approaches.
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Affiliation(s)
- Roberta Besio
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Chi-Wing Chow
- Bone and Extracellular Matrix Branch, NICHD, National Institute of Health, Bethesda, MD 20892, USA
| | - Francesca Tonelli
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Joan C Marini
- Bone and Extracellular Matrix Branch, NICHD, National Institute of Health, Bethesda, MD 20892, USA
| | - Antonella Forlino
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
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22
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Tiede-Lewis LM, Dallas SL. Changes in the osteocyte lacunocanalicular network with aging. Bone 2019; 122:101-113. [PMID: 30743014 PMCID: PMC6638547 DOI: 10.1016/j.bone.2019.01.025] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 01/28/2019] [Indexed: 12/22/2022]
Abstract
Osteoporosis is an aging-related disease of reduced bone mass that is particularly prevalent in post-menopausal women, but also affects the aged male population and is associated with increased fracture risk. Osteoporosis is the result of an imbalance whereby bone formation by osteoblasts no longer keeps pace with resorption of bone by osteoclasts. Osteocytes are the most abundant cells in bone and, although previously thought to be quiescent, they are now known to be active, multifunctional cells that play a key role in the maintenance of bone mass by regulating both osteoblast and osteoclast activity. They are also thought to regulate bone mass through their role as mechanoresponsive cells in bone that coordinate adaptive responses to mechanical loading. Osteocytes form an extensive interconnected network throughout the mineralized bone matrix and receive their nutrients as well as hormones and signaling factors through the lacunocanalicular system. Several studies have shown that the extent and connectivity of the lacunocanalicular system and osteocyte networks degenerates in aged humans as well as in animal models of aging. It is also known that the bone anabolic response to loading is decreased with aging. This review summarizes recent research on the degenerative changes that occur in osteocytes and their lacunocanalicular system as a result of aging and discusses the implications for skeletal health and homeostasis as well as potential mechanisms that may underlie these degenerative changes. Since osteocytes are such key regulators of skeletal homeostasis, maintaining the health of the osteocyte network would seem critical for maintenance of bone health. Therefore, a more complete understanding of the structure and function of the osteocyte network, its lacunocanalicular system, and the degenerative changes that occur with aging should lead to advances in our understanding of age related bone loss and potentially lead to improved therapies.
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Affiliation(s)
- LeAnn M Tiede-Lewis
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, Kansas City, MO 64108, United States of America
| | - Sarah L Dallas
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, Kansas City, MO 64108, United States of America.
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23
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Marcotti S, Maki K, Reilly GC, Lacroix D, Adachi T. Hyaluronic acid selective anchoring to the cytoskeleton: An atomic force microscopy study. PLoS One 2018; 13:e0206056. [PMID: 30359403 PMCID: PMC6201909 DOI: 10.1371/journal.pone.0206056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 10/07/2018] [Indexed: 11/19/2022] Open
Abstract
The hyaluronic acid component of the glycocalyx plays a role in cell mechanotransduction by selectively transmitting mechanical signals to the cell cytoskeleton or to the cell membrane. The aim of this study was to evaluate the mechanical link between the hyaluronic acid molecule and the cell cytoskeleton by means of atomic force microscopy single molecule force spectroscopy. Hyaluronic acid molecules on live cells were targeted with probes coated with hyaluronic acid binding protein. Two different types of events were observed when the detachment of the target molecule from the probe occurred, suggesting the presence of cytoskeleton- and membrane-anchored molecules. Membrane-anchored molecules facilitated the formation of tethers when pulled. About 15% of the tested hyaluronic acid molecules were shown to be anchored to the cytoskeleton. When multiple molecules bonded to the probe, specific detachment patterns were observed, suggesting that a cytoskeletal bond needed to be broken to improve the ability to pull tethers from the cell membrane. This likely resulted in the formation of tethering structures maintaining a cytoskeletal core similar to the ones observed for cells over-expressing HA synthases. The different observed rupture events were associated with separate mechanotransductive mechanisms in an analogous manner to that previously proposed for the endothelial glycocalyx. Single cytoskeleton anchored rupture events represent HA molecules linked to the cytoskeleton and therefore transmitting mechanical stimuli into the inner cell compartments. Single membrane tethers would conversely represent the glycocalyx molecules connected to areas of the membrane where an abundance of signalling molecules reside.
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Affiliation(s)
- Stefania Marcotti
- Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Koichiro Maki
- Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
- Department of Mechanical Engineering, University of Tokyo, Tokyo, Japan
| | - Gwendolen C. Reilly
- Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, United Kingdom
| | - Damien Lacroix
- Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom
| | - Taiji Adachi
- Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
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24
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Ben-Shmuel A, Joseph N, Barda-Saad M. Commentary: Integrins Modulate T Cell Receptor Signaling by Constraining Actin Flow at the Immunological Synapse. Front Immunol 2018; 9:2110. [PMID: 30283450 PMCID: PMC6157412 DOI: 10.3389/fimmu.2018.02110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 08/28/2018] [Indexed: 12/13/2022] Open
Affiliation(s)
- Aviad Ben-Shmuel
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Noah Joseph
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Mira Barda-Saad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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25
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Srivastava T, Thiagarajan G, Alon US, Sharma R, El-Meanawy A, McCarthy ET, Savin VJ, Sharma M. Role of biomechanical forces in hyperfiltration-mediated glomerular injury in congenital anomalies of the kidney and urinary tract. Nephrol Dial Transplant 2018; 32:759-765. [PMID: 28339567 DOI: 10.1093/ndt/gfw430] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 11/15/2016] [Indexed: 11/13/2022] Open
Abstract
Congenital anomalies of the kidney and urinary tract (CAKUT) including solitary kidney constitute the main cause of progressive chronic kidney disease (CKD) in children. Children born with CAKUT develop signs of CKD only during adolescence and do not respond to renin-angiotensin-aldosterone system blockers. Early cellular changes underlying CKD progression to end-stage renal disease by early adulthood are not well understood. The mechanism of maladaptive hyperfiltration that occurs from loss of functional nephrons, including solitary kidney, is not clear. We re-examine the phenomenon of hyperfiltration in the context of biomechanical forces with special reference to glomerular podocytes. Capillary stretch exerts tensile stress on podocytes through the glomerular basement membrane. The flow of ultrafiltrate over the cell surface directly causes fluid flow shear stress (FFSS) on podocytes. FFSS on the podocyte surface increases 1.5- to 2-fold in animal models of solitary kidney and its effect on podocytes is a subject of ongoing research. Podocytes (i) are mechanosensitive to tensile and shear forces, (ii) use prostaglandin E2, angiotensin-II or nitric oxide for mechanoperception and (iii) use specific signaling pathways for mechanotransduction. We discuss (i) the nature of and differences in cellular responses to biomechanical forces, (ii) methods to study biomechanical forces and (iii) effects of biomechanical forces on podocytes and glomeruli. Future studies on FFSS will likely identify novel targets for strategies for early intervention to complement and strengthen the current regimen for treating children with CAKUT.
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Affiliation(s)
- Tarak Srivastava
- Section of Nephrology, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO, USA.,Renal Research Laboratory, Research and Development, Kansas City VA Medical Center, Kansas City, MO, USA
| | - Ganesh Thiagarajan
- School of Computing and Engineering, University of Missouri at Kansas City, MO, USA
| | - Uri S Alon
- Section of Nephrology, Children's Mercy Hospital and University of Missouri at Kansas City, Kansas City, MO, USA
| | - Ram Sharma
- Renal Research Laboratory, Research and Development, Kansas City VA Medical Center, Kansas City, MO, USA
| | - Ashraf El-Meanawy
- Division of Nephrology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Ellen T McCarthy
- Kidney Institute, Kansas University Medical Center, Kansas City, KS, USA
| | - Virginia J Savin
- Renal Research Laboratory, Research and Development, Kansas City VA Medical Center, Kansas City, MO, USA
| | - Mukut Sharma
- Renal Research Laboratory, Research and Development, Kansas City VA Medical Center, Kansas City, MO, USA
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26
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Lagendijk AK, Gomez GA, Baek S, Hesselson D, Hughes WE, Paterson S, Conway DE, Belting HG, Affolter M, Smith KA, Schwartz MA, Yap AS, Hogan BM. Live imaging molecular changes in junctional tension upon VE-cadherin in zebrafish. Nat Commun 2017; 8:1402. [PMID: 29123087 PMCID: PMC5680264 DOI: 10.1038/s41467-017-01325-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 09/08/2017] [Indexed: 12/11/2022] Open
Abstract
Forces play diverse roles in vascular development, homeostasis and disease. VE-cadherin at endothelial cell-cell junctions links the contractile acto-myosin cytoskeletons of adjacent cells, serving as a tension-transducer. To explore tensile changes across VE-cadherin in live zebrafish, we tailored an optical biosensor approach, originally established in vitro. We validate localization and function of a VE-cadherin tension sensor (TS) in vivo. Changes in tension across VE-cadherin observed using ratio-metric or lifetime FRET measurements reflect acto-myosin contractility within endothelial cells. Furthermore, we apply the TS to reveal biologically relevant changes in VE-cadherin tension that occur as the dorsal aorta matures and upon genetic and chemical perturbations during embryonic development. Mechanical forces play a crucial role during morphogenesis, but how these are sensed and transduced in vivo is not fully understood. Here the authors apply a FRET tension sensor to live zebrafish and study changes in VE-cadherin tension at endothelial cell-cell junctions during arterial maturation.
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Affiliation(s)
- Anne Karine Lagendijk
- Institute for Molecular Bioscience, Genomics of Development and Disease division, The University of Queensland, 306 Carmody Road, St Lucia, 4072, QLD, Australia.
| | - Guillermo A Gomez
- Institute for Molecular Bioscience, Cell Biology and Molecular Medicine division, The University of Queensland, 306 Carmody Road, St Lucia, 4072, QLD, Australia.,Centre for Cancer Biology, SA Pathology and the University of South Australia, Frome Road, Adelaide, 5000, SA, Australia
| | - Sungmin Baek
- Institute for Molecular Bioscience, Genomics of Development and Disease division, The University of Queensland, 306 Carmody Road, St Lucia, 4072, QLD, Australia
| | - Daniel Hesselson
- Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, 2010, NSW, Australia
| | - William E Hughes
- Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, 2010, NSW, Australia
| | - Scott Paterson
- Institute for Molecular Bioscience, Genomics of Development and Disease division, The University of Queensland, 306 Carmody Road, St Lucia, 4072, QLD, Australia
| | - Daniel E Conway
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, 23284, USA
| | - Heinz-Georg Belting
- Biozentrum der Universität Basel, Klingelbergstrasse 70, 4056, Basel, Switzerland
| | - Markus Affolter
- Biozentrum der Universität Basel, Klingelbergstrasse 70, 4056, Basel, Switzerland
| | - Kelly A Smith
- Institute for Molecular Bioscience, Genomics of Development and Disease division, The University of Queensland, 306 Carmody Road, St Lucia, 4072, QLD, Australia
| | - Martin A Schwartz
- Yale Cardiovascular Research Center and Department of Internal Medicine, Cardiovascular Medicine, Yale University School of Medicine, New Haven, CT, 06510, USA
| | - Alpha S Yap
- Institute for Molecular Bioscience, Cell Biology and Molecular Medicine division, The University of Queensland, 306 Carmody Road, St Lucia, 4072, QLD, Australia
| | - Benjamin M Hogan
- Institute for Molecular Bioscience, Genomics of Development and Disease division, The University of Queensland, 306 Carmody Road, St Lucia, 4072, QLD, Australia
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27
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Abstract
PURPOSE OF REVIEW Over the past decades, osteocytes have emerged as mechano-sensors of bone and master regulators of bone homeostasis. This article summarizes latest research and progress made in understanding osteocyte mechanobiology and critically reviews tools currently available to study these cells. RECENT FINDINGS Whereas increased mechanical forces promote bone formation, decrease loading is always associated with bone loss and skeletal fragility. Recent studies identified cilia, integrins, calcium channels, and G-protein coupled receptors as important sensors of mechanical forces and Ca2+ and cAMP signaling as key effectors. Among transcripts regulated by mechanical forces, sclerostin and RANKL have emerged as potential therapeutic targets for disuse-induced bone loss. In this paper, we review the mechanisms by which osteocytes perceive and transduce mechanical cues and the models available to study mechano-transduction. Future directions of the field are also discussed.
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Affiliation(s)
- Yuhei Uda
- Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, MA, USA
| | - Ehab Azab
- Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, MA, USA
| | - Ningyuan Sun
- Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, MA, USA
| | - Chao Shi
- Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, MA, USA
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, Shaanxi Province, People's Republic of China
| | - Paola Divieti Pajevic
- Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, MA, USA.
- , 700 Albany Street, W201C, Boston, MA, 02118, USA.
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28
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Shen Y, Cheng Y, Uyeda TQP, Plaza GR. Cell Mechanosensors and the Possibilities of Using Magnetic Nanoparticles to Study Them and to Modify Cell Fate. Ann Biomed Eng 2017; 45:2475-2486. [PMID: 28744841 DOI: 10.1007/s10439-017-1884-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 07/07/2017] [Indexed: 12/13/2022]
Abstract
The use of magnetic nanoparticles (MNPs) is a promising technique for future advances in biomedical applications. This idea is supported by the availability of MNPs that can target specific cell components, the variety of shapes of MNPs and the possibility of finely controlling the applied magnetic forces. To examine this opportunity, here we review the current developments in the use of MNPs to mechanically stimulate cells and, specifically, the cell mechanotransduction systems. We analyze the cell components that may act as mechanosensors and their effect on cell fate and we focus on the promising possibilities of controlling stem-cell differentiation, inducing cancer-cell death and treating nervous-system diseases.
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Affiliation(s)
- Yajing Shen
- The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, 200120, China
| | - Yu Cheng
- The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, 200120, China.
| | - Taro Q P Uyeda
- The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, 200120, China.,Department of Physics, Faculty of Science and Engineering, Waseda University, Tokyo, 169-8555, Japan
| | - Gustavo R Plaza
- The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, 200120, China. .,Center for Biomedical Technology, Universidad Politécnica de Madrid, 28223, Pozuelo de Alarcón, Spain.
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29
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Lin W, Izu Y, Smriti A, Kawasaki M, Pawaputanon C, Böttcher RT, Costell M, Moriyama K, Noda M, Ezura Y. Profilin1 is expressed in osteocytes and regulates cell shape and migration. J Cell Physiol 2017; 233:259-268. [PMID: 28233307 DOI: 10.1002/jcp.25872] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 02/22/2017] [Indexed: 02/06/2023]
Abstract
Osteocytes are the most abundant cells in bone and regulate bone metabolism in coordination with osteoblasts and osteoclasts. However, the molecules that control osteocytes are still incompletely understood. Profilin1 is an actin-binding protein that is involved in actin polymerization. Osteocytes possess characteristic dendritic process formed based on actin cytoskeleton. Here, we examined the expression of profilin1 and its function in osteocytes. Profilin1 mRNA was expressed in osteocytic MLO-Y4 cells and its levels were gradually increased along with the time in culture. With regard to functional aspect, knockdown of profilin1 by siRNA enhanced BMP-induced increase in alkaline phosphatase expression levels in MLO-Y4 cells. Profilin1 knockdown suppressed the levels of dendritic processes and migration of MLO-Y4 cells. Since aging causes an increase in ROS in the body, we further examined the effects of hydrogen peroxide on the expression of profilin1. Hydrogen peroxide treatment increased the levels of profilin1 mRNA in MLO-Y4 cells in contrast to the decline in alkaline phosphatase. Profilin1 was expressed not only in MLO-Y4cells but also in the primary cultures of osteocytes. Importantly, profilin1 mRNA levels in primary cultures of osteocytes were higher than those in primary cultures of osteoblasts. To examine in vivo role of profilin1 in osteocytes, profilin1 was conditionally knocked out by using DMP1-cre and profilin1 floxed mice. This conditional deletion of profilin1 specifically in osteocytes resulted in reduction in the levels of bone volume and bone mineral density. These data indicate that profilin1 is expressed in osteocytes and regulates cell shape, migration and bone mass.
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Affiliation(s)
- Wanting Lin
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan.,Department of Maxillofacial Orthognathics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yayoi Izu
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Arayal Smriti
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Makiri Kawasaki
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Chantida Pawaputanon
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ralph T Böttcher
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Mercedes Costell
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Keiji Moriyama
- Department of Maxillofacial Orthognathics, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masaki Noda
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan.,Yokohama City Minato Red Cross Hospital, Yokohama, Kanagawa, Japan.,Department of Orthopedic Surgery, School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoichi Ezura
- Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan
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30
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Li N, Wong CK, Cheng CY. Plastins regulate ectoplasmic specialization via its actin bundling activity on microfilaments in the rat testis. Asian J Androl 2017; 18:716-22. [PMID: 26608945 PMCID: PMC5000794 DOI: 10.4103/1008-682x.166583] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Plastins are a family of actin binding proteins (ABPs) known to cross-link actin microfilaments in mammalian cells, creating actin microfilament bundles necessary to confer cell polarity and cell shape. Plastins also support cell movement in response to changes in environment, involved in cell/tissue growth and development. They also confer plasticity to cells and tissues in response to infection or other pathological conditions (e.g., inflammation). In the testis, the cell-cell anchoring junction unique to the testis that is found at the Sertoli cell-cell interface at the blood-testis barrier (BTB) and at the Sertoli-spermatid (e.g., 8–19 spermatids in the rat testis) is the basal and the apical ectoplasmic specialization (ES), respectively. The ES is an F-actin-rich anchoring junction constituted most notably by actin microfilament bundles. A recent report using RNAi that specifically knocks down plastin 3 has yielded some insightful information regarding the mechanism by which plastin 3 regulates the status of actin microfilament bundles at the ES via its intrinsic actin filament bundling activity. Herein, we provide a brief review on the role of plastins in the testis in light of this report, which together with recent findings in the field, we propose a likely model by which plastins regulate ES function during the epithelial cycle of spermatogenesis via their intrinsic activity on actin microfilament organization in the rat testis.
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Affiliation(s)
- Nan Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York 10065, USA
| | - Chris Kc Wong
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York 10065, USA
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31
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Linan-Rico A, Ochoa-Cortes F, Beyder A, Soghomonyan S, Zuleta-Alarcon A, Coppola V, Christofi FL. Mechanosensory Signaling in Enterochromaffin Cells and 5-HT Release: Potential Implications for Gut Inflammation. Front Neurosci 2016; 10:564. [PMID: 28066160 PMCID: PMC5165017 DOI: 10.3389/fnins.2016.00564] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/22/2016] [Indexed: 12/12/2022] Open
Abstract
Enterochromaffin (EC) cells synthesize 95% of the body 5-HT and release 5-HT in response to mechanical or chemical stimulation. EC cell 5-HT has physiological effects on gut motility, secretion and visceral sensation. Abnormal regulation of 5-HT occurs in gastrointestinal disorders and Inflammatory Bowel Diseases (IBD) where 5-HT may represent a key player in the pathogenesis of intestinal inflammation. The focus of this review is on mechanism(s) involved in EC cell "mechanosensation" and critical gaps in our knowledge for future research. Much of our knowledge and concepts are from a human BON cell model of EC, although more recent work has included other cell lines, native EC cells from mouse and human and intact mucosa. EC cells are "mechanosensors" that respond to physical forces generated during peristaltic activity by translating the mechanical stimulus (MS) into an intracellular biochemical response leading to 5-HT and ATP release. The emerging picture of mechanosensation includes Piezo 2 channels, caveolin-rich microdomains, and tight regulation of 5-HT release by purines. The "purinergic hypothesis" is that MS releases purines to act in an autocrine/paracrine manner to activate excitatory (P2Y1, P2Y4, P2Y6, and A2A/A2B) or inhibitory (P2Y12, A1, and A3) receptors to regulate 5-HT release. MS activates a P2Y1/Gαq/PLC/IP3-IP3R/SERCA Ca2+signaling pathway, an A2A/A2B-Gs/AC/cAMP-PKA signaling pathway, an ATP-gated P2X3 channel, and an inhibitory P2Y12-Gi/o/AC-cAMP pathway. In human IBD, P2X3 is down regulated and A2B is up regulated in EC cells, but the pathophysiological consequences of abnormal mechanosensory or purinergic 5-HT signaling remain unknown. EC cell mechanosensation remains poorly understood.
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Affiliation(s)
- Andromeda Linan-Rico
- Department of Anesthesiology, Wexner Medical Center at Ohio State UniversityColumbus, OH, USA; CONACYT-Centro Universitario de Investigaciones Biomedicas, University of ColimaColima, Mexico
| | - Fernando Ochoa-Cortes
- Department of Anesthesiology, Wexner Medical Center at Ohio State University Columbus, OH, USA
| | - Arthur Beyder
- Enteric Neuroscience Program, Division of Gastroenterology and Hepatology, Department of Physiology and Biomedical Engineering, Mayo Clinic Rochester, MN, USA
| | - Suren Soghomonyan
- Department of Anesthesiology, Wexner Medical Center at Ohio State University Columbus, OH, USA
| | - Alix Zuleta-Alarcon
- Department of Anesthesiology, Wexner Medical Center at Ohio State University Columbus, OH, USA
| | - Vincenzo Coppola
- SBS-Cancer Biology and Genetics, Ohio State University Columbus, OH, USA
| | - Fievos L Christofi
- Department of Anesthesiology, Wexner Medical Center at Ohio State University Columbus, OH, USA
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32
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Seref-Ferlengez Z, Suadicani SO, Thi MM. A new perspective on mechanisms governing skeletal complications in type 1 diabetes. Ann N Y Acad Sci 2016; 1383:67-79. [PMID: 27571221 DOI: 10.1111/nyas.13202] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/11/2016] [Accepted: 07/18/2016] [Indexed: 12/29/2022]
Abstract
This review focuses on bone mechanobiology in type 1 diabetes (T1D), an area of research on diabetes-associated skeletal complications that is still in its infancy. We first provide a brief overview of the deleterious effects of diabetes on the skeleton and of the knowledge gained from studies with rodent models of T1D. Second, we discuss two specific hallmarks of T1D, low insulin and high glucose, and address the extent to which they affect skeletal health. Third, we highlight the mechanosensitive nature of bone tissue and the importance of mechanical loading for bone health. We also summarize recent advances in bone mechanobiology that implicate osteocytes as the mechanosensors and major regulatory cells in the bone. Finally, we discuss recent evidence indicating that the diabetic bone is "deaf" to mechanical loading and that osteocytes are central players in mechanisms that lead to bone loss in T1D.
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Affiliation(s)
- Zeynep Seref-Ferlengez
- Department of Orthopaedic Surgery.,Laboratories of Musculoskeletal Orthopedic Research at Einstein-Montefiore (MORE)
| | - Sylvia O Suadicani
- Laboratories of Musculoskeletal Orthopedic Research at Einstein-Montefiore (MORE).,Department of Neuroscience.,Department of Urology, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York
| | - Mia M Thi
- Department of Orthopaedic Surgery.,Laboratories of Musculoskeletal Orthopedic Research at Einstein-Montefiore (MORE).,Department of Neuroscience
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Abstract
Cells are covered by a surface layer of glycans that is referred to as the 'glycocalyx'. In this review, we focus on the role of the glycocalyx in vascular diseases (atherosclerosis, stroke, hypertension, kidney disease and sepsis) and cancer. The glycocalyx and its principal glycosaminoglycans [heparan sulphate (HS) and hyaluronic acid (HA)] and core proteins (syndecans and glypicans) are degraded in vascular diseases, leading to a breakdown of the vascular permeability barrier, enhanced access of leucocytes to the arterial intima that propagate inflammation and alteration of endothelial mechanotransduction mechanisms that protect against disease. By contrast, the glycocalyx on cancer cells is generally robust, promoting integrin clustering and growth factor signalling, and mechanotransduction of interstitial flow shear stress that is elevated in tumours to upregulate matrix metalloproteinase release which enhances cell motility and metastasis. HS and HA are consistently elevated on cancer cells and are associated with tumour growth and metastasis. Later, we will review the agents that might be used to enhance or protect the glycocalyx to combat vascular disease, as well as a different set of compounds that can degrade the cancer cell glycocalyx to suppress cell growth and metastasis. It is clear that what is beneficial for either vascular disease or cancer will not be so for the other. The overarching conclusions are that (i) the importance of the glycocalyx in human medicine is only beginning to be recognized, and (ii) more detailed studies of glycocalyx involvement in vascular diseases and cancer will lead to novel treatment modalities.
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Affiliation(s)
- J M Tarbell
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
| | - L M Cancel
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
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Carrisoza-Gaytan R, Carattino MD, Kleyman TR, Satlin LM. An unexpected journey: conceptual evolution of mechanoregulated potassium transport in the distal nephron. Am J Physiol Cell Physiol 2015; 310:C243-59. [PMID: 26632600 DOI: 10.1152/ajpcell.00328.2015] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Flow-induced K secretion (FIKS) in the aldosterone-sensitive distal nephron (ASDN) is mediated by large-conductance, Ca(2+)/stretch-activated BK channels composed of pore-forming α-subunits (BKα) and accessory β-subunits. This channel also plays a critical role in the renal adaptation to dietary K loading. Within the ASDN, the cortical collecting duct (CCD) is a major site for the final renal regulation of K homeostasis. Principal cells in the ASDN possess a single apical cilium whereas the surfaces of adjacent intercalated cells, devoid of cilia, are decorated with abundant microvilli and microplicae. Increases in tubular (urinary) flow rate, induced by volume expansion, diuretics, or a high K diet, subject CCD cells to hydrodynamic forces (fluid shear stress, circumferential stretch, and drag/torque on apical cilia and presumably microvilli/microplicae) that are transduced into increases in principal (PC) and intercalated (IC) cell cytoplasmic Ca(2+) concentration that activate apical voltage-, stretch- and Ca(2+)-activated BK channels, which mediate FIKS. This review summarizes studies by ourselves and others that have led to the evolving picture that the BK channel is localized in a macromolecular complex at the apical membrane, composed of mechanosensitive apical Ca(2+) channels and a variety of kinases/phosphatases as well as other signaling molecules anchored to the cytoskeleton, and that an increase in tubular fluid flow rate leads to IC- and PC-specific responses determined, in large part, by the cell-specific composition of the BK channels.
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Affiliation(s)
| | - Marcelo D Carattino
- Renal-Electrolyte Division, Department of Medicine, Pittsburgh, Pennsylvania
| | - Thomas R Kleyman
- Renal-Electrolyte Division, Department of Medicine, Pittsburgh, Pennsylvania
| | - Lisa M Satlin
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York; and
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Maggiorani D, Dissard R, Belloy M, Saulnier-Blache JS, Casemayou A, Ducasse L, Grès S, Bellière J, Caubet C, Bascands JL, Schanstra JP, Buffin-Meyer B. Shear Stress-Induced Alteration of Epithelial Organization in Human Renal Tubular Cells. PLoS One 2015; 10:e0131416. [PMID: 26146837 PMCID: PMC4493045 DOI: 10.1371/journal.pone.0131416] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 06/02/2015] [Indexed: 12/14/2022] Open
Abstract
Tubular epithelial cells in the kidney are continuously exposed to urinary fluid shear stress (FSS) generated by urine movement and recent in vitro studies suggest that changes of FSS could contribute to kidney injury. However it is unclear whether FSS alters the epithelial characteristics of the renal tubule. Here, we evaluated in vitro and in vivo the influence of FSS on epithelial characteristics of renal proximal tubular cells taking the organization of junctional complexes and the presence of the primary cilium as markers of epithelial phenotype. Human tubular cells (HK-2) were subjected to FSS (0.5 Pa) for 48h. Control cells were maintained under static conditions. Markers of tight junctions (Claudin-2, ZO-1), Par polarity complex (Pard6), adherens junctions (E-Cadherin, β-Catenin) and the primary cilium (α-acetylated Tubulin) were analysed by quantitative PCR, Western blot or immunocytochemistry. In response to FSS, Claudin-2 disappeared and ZO-1 displayed punctuated and discontinuous staining in the plasma membrane. Expression of Pard6 was also decreased. Moreover, E-Cadherin abundance was decreased, while its major repressors Snail1 and Snail2 were overexpressed, and β-Catenin staining was disrupted along the cell periphery. Finally, FSS subjected-cells exhibited disappeared primary cilium. Results were confirmed in vivo in a uninephrectomy (8 months) mouse model where increased FSS induced by adaptive hyperfiltration in remnant kidney was accompanied by both decreased epithelial gene expression including ZO-1, E-cadherin and β-Catenin and disappearance of tubular cilia. In conclusion, these results show that proximal tubular cells lose an important number of their epithelial characteristics after long term exposure to FSS both in vitro and in vivo. Thus, the changes in urinary FSS associated with nephropathies should be considered as potential insults for tubular cells leading to disorganization of the tubular epithelium.
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Affiliation(s)
- Damien Maggiorani
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Romain Dissard
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Marcy Belloy
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Jean-Sébastien Saulnier-Blache
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Audrey Casemayou
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Laure Ducasse
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Sandra Grès
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Julie Bellière
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Cécile Caubet
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Jean-Loup Bascands
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Joost P. Schanstra
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
| | - Bénédicte Buffin-Meyer
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1048, Toulouse, France
- Université Toulouse III Paul Sabatier, Institute of Metabolic and Cardiovascular Diseases - I2MC, Toulouse, France
- * E-mail:
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Oshibe T, Hayase T, Funamoto K, Shirai A. Numerical analysis for elucidation of nonlinear frictional characteristics of a deformed erythrocyte moving on a plate in medium subject to inclined centrifugal force. J Biomech Eng 2015; 136:121003. [PMID: 25271707 DOI: 10.1115/1.4028723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 09/28/2014] [Indexed: 11/08/2022]
Abstract
Complex interactions between blood cells, plasma proteins, and glycocalyx in the endothelial surface layer are crucial in microcirculation. To obtain measurement data of such interactions, we have previously performed experiments using an inclined centrifuge microscope, which revealed that the nonlinear velocity-friction characteristics of erythrocytes moving on an endothelia-cultured glass plate in medium under inclined centrifugal force are much larger than those on plain or material-coated glass plates. The purpose of this study was to elucidate the nonlinear frictional characteristics of an erythrocyte on plain or material-coated glass plates as the basis to clarify the interaction between the erythrocyte and the endothelial cells. We propose a model in which steady motion of the cell is realized as an equilibrium state of the force and moment due to inclined centrifugal force and hydrodynamic flow force acting on the cell. Other electrochemical effects on the surfaces of the erythrocyte and the plate are ignored for the sake of simplicity. Numerical analysis was performed for a three-dimensional flow of a mixture of plasma and saline around a rigid erythrocyte model of an undeformed biconcave shape and a deformed shape with a concave top surface and a flat bottom surface. A variety of conditions for the concentration of plasma in a medium, the velocity of the cell, and the minimum gap width and the angle of attack of the cell from the plate, were examined to obtain the equilibrium states. A simple flat plate model based on the lubrication theory was also examined to elucidate the physical meaning of the model. The equilibrium angle of attack was obtained only for the deformed cell model and was represented as a power function of the minimum gap width. A simple flat plate model qualitatively explains the power function relation of the frictional characteristics, but it cannot explain the equilibrium relation, confirming the computational result that the deformation of the cell is necessary for the equilibrium. The frictional characteristics obtained from the present computation qualitatively agree with those of former experiments, showing the validity of the proposed model.
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37
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Li N, Mruk DD, Wong CKC, Lee WM, Han D, Cheng CY. Actin-bundling protein plastin 3 is a regulator of ectoplasmic specialization dynamics during spermatogenesis in the rat testis. FASEB J 2015; 29:3788-805. [PMID: 26048141 DOI: 10.1096/fj.14-267997] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/18/2015] [Indexed: 12/13/2022]
Abstract
Ectoplasmic specialization (ES) is an actin-rich adherens junction in the seminiferous epithelium of adult mammalian testes. ES is restricted to the Sertoli-spermatid (apical ES) interface, as well as the Sertoli cell-cell (basal ES) interface at the blood-testis barrier (BTB). ES is typified by the presence of an array of bundles of actin microfilaments near the Sertoli cell plasma membrane. These actin microfilament bundles require rapid debundling to convert them from a bundled to branched/unbundled configuration and vice versa to confer plasticity to support the transport of 1) spermatids in the adluminal compartment and 2) preleptotene spermatocytes at the BTB while maintaining cell adhesion. Plastin 3 is one of the plastin family members abundantly found in yeast, plant and animal cells that confers actin microfilaments their bundled configuration. Herein, plastin 3 was shown to be a component of the apical and basal ES in the rat testis, displaying spatiotemporal expression during the epithelial cycle. A knockdown (KD) of plastin 3 in Sertoli cells by RNA interference using an in vitro model to study BTB function showed that a transient loss of plastin 3 perturbed the Sertoli cell tight junction-permeability barrier, mediated by changes in the localization of basal ES proteins N-cadherin and β-catenin. More importantly, these changes were the result of an alteration of the actin microfilaments, converting from their bundled to branched configuration when examined microscopically, and validated by biochemical assays that quantified actin-bundling and polymerization activity. Moreover, these changes were confirmed by studies in vivo by plastin 3 KD in the testis in which mis-localization of N-cadherin and β-catenin was also detected at the BTB, concomitant with defects in the transport of spermatids and phagosomes and a disruption of cell adhesion most notably in elongated spermatids due to a loss of actin-bundling capability at the apical ES, which in turn affected localization of adhesion protein complexes at the site. In summary, plastin 3 is a regulator of actin microfilament bundles at the ES in which it dictates the configuration of the filamentous actin network by assuming either a bundled or unbundled/branched configuration via changes in its spatiotemporal expression during the epithelial cycle.
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Affiliation(s)
- Nan Li
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Dolores D Mruk
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Chris K C Wong
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Will M Lee
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Daishu Han
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - C Yan Cheng
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
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Freedman BR, Bade ND, Riggin CN, Zhang S, Haines PG, Ong KL, Janmey PA. The (dys)functional extracellular matrix. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:3153-64. [PMID: 25930943 DOI: 10.1016/j.bbamcr.2015.04.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 04/11/2015] [Accepted: 04/13/2015] [Indexed: 10/23/2022]
Abstract
The extracellular matrix (ECM) is a major component of the biomechanical environment with which cells interact, and it plays important roles in both normal development and disease progression. Mechanical and biochemical factors alter the biomechanical properties of tissues by driving cellular remodeling of the ECM. This review provides an overview of the structural, compositional, and mechanical properties of the ECM that instruct cell behaviors. Case studies are reviewed that highlight mechanotransduction in the context of two distinct tissues: tendons and the heart. Although these two tissues demonstrate differences in relative cell-ECM composition and mechanical environment, they share similar mechanisms underlying ECM dysfunction and cell mechanotransduction. Together, these topics provide a framework for a fundamental understanding of the ECM and how it may vary across normal and diseased tissues in response to mechanical and biochemical cues. This article is part of a Special Issue entitled: Mechanobiology.
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Affiliation(s)
- Benjamin R Freedman
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Nathan D Bade
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Corinne N Riggin
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Sijia Zhang
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Philip G Haines
- Division of Cardiovascular Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Katy L Ong
- Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Paul A Janmey
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA; Department of Physiology, University of Pennsylvania, Philadelphia, PA, USA.
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Cheeniyil A, Evani SJ, Dallo SF, Ramasubramanian AK. Shear stress upregulates IL-1β secretion by Chlamydia pneumoniae- infected monocytes. Biotechnol Bioeng 2015; 112:838-42. [PMID: 25336058 DOI: 10.1002/bit.25486] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 09/19/2014] [Accepted: 10/13/2014] [Indexed: 12/13/2022]
Abstract
Infectious agents are increasingly implicated in the development and progression of chronic inflammatory diseases. Several lines of evidence suggest that the common intracellular respiratory pathogen, Chlamydia pneumoniae contributes to the well-established risk factors of atherosclerosis but the exact mechanism is not well understood. It is believed that C. pneumoniae-infected monocytes travel from the lung to the atherosclerotic foci, during which the cells experience mechanical stimuli due to blood flow. In this work, we characterized the effect of physiological levels of shear stress on C. pneumoniae-infected human monocytes in an in vitro flow model. We found that a shear stress of 5 dyn/cm(2) enhanced the expression of pro-inflammatory cytokine IL-1β only in infected, but not in uninfected, monocytes. We also found that this enhancement is due to the upregulation of IL-1β gene expression due to shear stress. Our results demonstrate that mechanotransduction is an important, heretofore unaddressed, determinant of inflammatory response to an infection.
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Affiliation(s)
- Aswathi Cheeniyil
- Department of Biomedical Engineering, and South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX, 78249.
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40
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Akiyama N, Yamamoto-Fukuda T, Takahashi H. Influence of continuous negative pressure in the rat middle ear. Laryngoscope 2014; 124:2404-10. [PMID: 24916143 DOI: 10.1002/lary.24767] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 04/14/2014] [Accepted: 05/12/2014] [Indexed: 11/10/2022]
Abstract
OBJECTIVES/HYPOTHESIS High negative pressure in the middle ear was thought to be closely related to the etiology of retraction-type cholesteatoma. Recently, it has been detected that mechanical forces are important factors in epithelial turnover and affect cytoskeletal remodeling. Continuous negative pressure in the middle ear may possibly accelerate the proliferation and differentiation of epithelial cells of the tympanic membrane. STUDY DESIGN Animal experimental study. METHODS Eleven adult male Sprague-Dawley rats were used, and continuous negative pressure was loaded by connecting a catheter from the rat's middle ear to the supply route of an implantable microinfusion pump, iPRECIO. At 7 days after implantation of the device, an otoendoscopic examination and micro-computed tomography (CT) analysis of the temporal bone were performed; the temporal bones were then collected for histological and immunohistochemical analysis. The degree of proliferation and differentiation of epithelial cells of the tympanic membrane was investigated immunohistochemically using the anti-cytokeratin-5 and anti-cytokeratin-10 antibodies. RESULTS Otoendoscopic examination revealed retraction of the pars flaccida in all of the ears under negative pressure. In the micro-CT analysis, soft tissue density area in the hypotympanum was observed in all ears under negative pressure. Histological analysis revealed thickened epithelium of the pars flaccida. In this region, the thickness of layers with cytokeratin-5-positive cells and cytokeratin-10-positive cells were increased. CONCLUSIONS Continuous negative pressure in the middle ear can lead to thickening of the epithelium of the pars flaccida, and may accelerate the proliferation and differentiation of epithelial cells.
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Affiliation(s)
- Naotaro Akiyama
- Department of Otolaryngology-Head and Neck Surgery, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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41
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Kaneko K, Ito M, Naoe Y, Lacy-Hulbert A, Ikeda K. Integrin αv in the mechanical response of osteoblast lineage cells. Biochem Biophys Res Commun 2014; 447:352-7. [PMID: 24726648 DOI: 10.1016/j.bbrc.2014.04.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 04/03/2014] [Indexed: 12/21/2022]
Abstract
Although osteoblast lineage cells, especially osteocytes, are thought to be a primary mechanosensory cell in bone, the identity of the mechano-receptor and downstream mechano-signaling pathways remain largely unknown. Here we show using osteoblastic cell model of mechanical stimulation with fluid shear stress that in the absence of integrin αv, phosphorylation of the Src substrate p130Cas and JNK was impaired, culminating in an inhibition of nuclear translocation of YAP/TAZ and subsequent transcriptional activation of target genes. Targeted deletion of the integrin αv in osteoblast lineage cells results in an attenuated response to mechanical loading in terms of Sost gene expression, indicative of a role for integrin αv in mechanoreception in vivo. Thus, integrin αv may be integral to a mechanosensing machinery in osteoblastic cells and involved in activation of a Src-JNK-YAP/TAZ pathway in response to mechanical stimulation.
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Affiliation(s)
- Keiko Kaneko
- Department of Bone and Joint Disease, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8511, Japan
| | - Masako Ito
- Medical Work-Life-Balance Center, Nagasaki University Hospital, Nagasaki 852-8501, Japan
| | - Yoshinori Naoe
- Department of Mechanism of Aging, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8511, Japan
| | - Adam Lacy-Hulbert
- Department of Pediatrics, Massachusetts General Hospital, Boston, MA 02114, United States
| | - Kyoji Ikeda
- Department of Bone and Joint Disease, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8511, Japan.
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van Dijk FS, Zillikens MC, Micha D, Riessland M, Marcelis CLM, de Die-Smulders CE, Milbradt J, Franken AA, Harsevoort AJ, Lichtenbelt KD, Pruijs HE, Rubio-Gozalbo ME, Zwertbroek R, Moutaouakil Y, Egthuijsen J, Hammerschmidt M, Bijman R, Semeins CM, Bakker AD, Everts V, Klein-Nulend J, Campos-Obando N, Hofman A, te Meerman GJ, Verkerk AJMH, Uitterlinden AG, Maugeri A, Sistermans EA, Waisfisz Q, Meijers-Heijboer H, Wirth B, Simon MEH, Pals G. PLS3 mutations in X-linked osteoporosis with fractures. N Engl J Med 2013; 369:1529-36. [PMID: 24088043 DOI: 10.1056/nejmoa1308223] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Plastin 3 (PLS3), a protein involved in the formation of filamentous actin (F-actin) bundles, appears to be important in human bone health, on the basis of pathogenic variants in PLS3 in five families with X-linked osteoporosis and osteoporotic fractures that we report here. The bone-regulatory properties of PLS3 were supported by in vivo analyses in zebrafish. Furthermore, in an additional five families (described in less detail) referred for diagnosis or ruling out of osteogenesis imperfecta type I, a rare variant (rs140121121) in PLS3 was found. This variant was also associated with a risk of fracture among elderly heterozygous women that was two times as high as that among noncarriers, which indicates that genetic variation in PLS3 is a novel etiologic factor involved in common, multi-factorial osteoporosis.
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Affiliation(s)
- Fleur S van Dijk
- Department of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands
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Abstract
Few investigators think of bone as an endocrine gland, even after the discovery that osteocytes produce circulating fibroblast growth factor 23 that targets the kidney and potentially other organs. In fact, until the last few years, osteocytes were perceived by many as passive, metabolically inactive cells. However, exciting recent discoveries have shown that osteocytes encased within mineralized bone matrix are actually multifunctional cells with many key regulatory roles in bone and mineral homeostasis. In addition to serving as endocrine cells and regulators of phosphate homeostasis, these cells control bone remodeling through regulation of both osteoclasts and osteoblasts, are mechanosensory cells that coordinate adaptive responses of the skeleton to mechanical loading, and also serve as a manager of the bone's reservoir of calcium. Osteocytes must survive for decades within the bone matrix, making them one of the longest lived cells in the body. Viability and survival are therefore extremely important to ensure optimal function of the osteocyte network. As we continue to search for new therapeutics, in addition to the osteoclast and the osteoblast, the osteocyte should be considered in new strategies to prevent and treat bone disease.
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Affiliation(s)
- Sarah L Dallas
- PhD, Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri-Kansas City, 650 East 25th Street, Kansas City, Missouri 64108.
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44
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Evani SJ, Dallo SF, Murthy AK, Ramasubramanian AK. Shear Stress Enhances Chemokine Secretion from Chlamydia pneumoniae-infected Monocytes. Cell Mol Bioeng 2013; 6:326-334. [PMID: 24505240 DOI: 10.1007/s12195-013-0291-x] [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: 12/19/2022] Open
Abstract
Chlamydia pneumoniae is a common respiratory pathogen that is considered a highly likely risk factor for atherosclerosis. C. pneumoniae is disseminated from the lung into systemic circulation via infected monocytes and lodges at the atherosclerotic sites. During transit, C. pneumoniae-infected monocytes in circulation are subjected to shear stress due to blood flow. The effect of mechanical stimuli on infected monocytes is largely understudied in the context of C. pneumoniae infection and inflammation. We hypothesized that fluid shear stress alters the inflammatory response of C. pneumoniae-infected monocytes and contributes to immune cell recruitment to the site of tissue damage. Using an in vitro model of blood flow, we determined that a physiological shear stress of 7.5 dyn/cm2 for 1 h on C. pneumoniae-infected monocytes enhances the production of several chemokines, which in turn is correlated with the recruitment of significantly large number of monocytes. Taken together, these results suggest synergistic interaction between mechanical and chemical factors in C. pneumoniae infection and associated inflammation.
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Affiliation(s)
- Shankar J Evani
- Department of Biomedical Engineering, and South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Shatha F Dallo
- Department of Biomedical Engineering, and South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Ashlesh K Murthy
- Departments of Pathology and Dental Medicine, Midwestern University, Downers Grove, IL 60515, USA
| | - Anand K Ramasubramanian
- Department of Biomedical Engineering, and South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX 78249, USA
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Cheng X, Zhang W, Ji Y, Meng J, Guo H, Liu J, Wu X, Xu H. Revealing silver cytotoxicity using Au nanorods/Ag shell nanostructures: disrupting cell membrane and causing apoptosis through oxidative damage. RSC Adv 2013. [DOI: 10.1039/c2ra23131j] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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