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Esser L, Springer R, Dreissen G, Lövenich L, Konrad J, Hampe N, Merkel R, Hoffmann B, Noetzel E. Elastomeric Pillar Cages Modulate Actomyosin Contractility of Epithelial Microtissues by Substrate Stiffness and Topography. Cells 2023; 12:cells12091256. [PMID: 37174659 PMCID: PMC10177551 DOI: 10.3390/cells12091256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/19/2023] [Accepted: 04/21/2023] [Indexed: 05/15/2023] Open
Abstract
Cell contractility regulates epithelial tissue geometry development and homeostasis. The underlying mechanobiological regulation circuits are poorly understood and experimentally challenging. We developed an elastomeric pillar cage (EPC) array to quantify cell contractility as a mechanoresponse of epithelial microtissues to substrate stiffness and topography. The spatially confined EPC geometry consisted of 24 circularly arranged slender pillars (1.2 MPa, height: 50 µm; diameter: 10 µm, distance: 5 µm). These high-aspect-ratio pillars were confined at both ends by planar substrates with different stiffness (0.15-1.2 MPa). Analytical modeling and finite elements simulation retrieved cell forces from pillar displacements. For evaluation, highly contractile myofibroblasts and cardiomyocytes were assessed to demonstrate that the EPC device can resolve static and dynamic cellular force modes. Human breast (MCF10A) and skin (HaCaT) cells grew as adherence junction-stabilized 3D microtissues within the EPC geometry. Planar substrate areas triggered the spread of monolayered clusters with substrate stiffness-dependent actin stress fiber (SF)-formation and substantial single-cell actomyosin contractility (150-200 nN). Within the same continuous microtissues, the pillar-ring topography induced the growth of bilayered cell tubes. The low effective pillar stiffness overwrote cellular sensing of the high substrate stiffness and induced SF-lacking roundish cell shapes with extremely low cortical actin tension (11-15 nN). This work introduced a versatile biophysical tool to explore mechanobiological regulation circuits driving low- and high-tensional states during microtissue development and homeostasis. EPC arrays facilitate simultaneously analyzing the impact of planar substrate stiffness and topography on microtissue contractility, hence microtissue geometry and function.
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Affiliation(s)
- Lisann Esser
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Ronald Springer
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Georg Dreissen
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Lukas Lövenich
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Jens Konrad
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Nico Hampe
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Rudolf Merkel
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Bernd Hoffmann
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Erik Noetzel
- Institute of Biological Information Processing 2 (IBI-2): Mechanobiology, Forschungszentrum Jülich, 52428 Jülich, Germany
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Hoffmann M, Gerlach S, Takamiya M, Tarazi S, Hersch N, Csiszár A, Springer R, Dreissen G, Scharr H, Rastegar S, Beil T, Strähle U, Merkel R, Hoffmann B. Smuggling on the Nanoscale-Fusogenic Liposomes Enable Efficient RNA-Transfer with Negligible Immune Response In Vitro and In Vivo. Pharmaceutics 2023; 15:pharmaceutics15041210. [PMID: 37111695 PMCID: PMC10146161 DOI: 10.3390/pharmaceutics15041210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/04/2023] [Accepted: 04/05/2023] [Indexed: 04/29/2023] Open
Abstract
The efficient and biocompatible transfer of nucleic acids into mammalian cells for research applications or medical purposes is a long-standing, challenging task. Viral transduction is the most efficient transfer system, but often entails high safety levels for research and potential health impairments for patients in medical applications. Lipo- or polyplexes are commonly used transfer systems but result in comparably low transfer efficiencies. Moreover, inflammatory responses caused by cytotoxic side effects were reported for these transfer methods. Often accountable for these effects are various recognition mechanisms for transferred nucleic acids. Using commercially available fusogenic liposomes (Fuse-It-mRNA), we established highly efficient and fully biocompatible transfer of RNA molecules for in vitro as well as in vivo applications. We demonstrated bypassing of endosomal uptake routes and, therefore, of pattern recognition receptors that recognize nucleic acids with high efficiency. This may underlie the observed almost complete abolishment of inflammatory cytokine responses. RNA transfer experiments into zebrafish embryos and adult animals fully confirmed the functional mechanism and the wide range of applications from single cells to organisms.
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Affiliation(s)
- Marco Hoffmann
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Sven Gerlach
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Masanari Takamiya
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Postfach 3640, 76021 Karlsruhe, Germany
| | - Samar Tarazi
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Nils Hersch
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Agnes Csiszár
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Ronald Springer
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Georg Dreissen
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Hanno Scharr
- IAS-8: Data Analytics and Machine Learning, Institute for Advanced Simulation, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Sepand Rastegar
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Postfach 3640, 76021 Karlsruhe, Germany
| | - Tanja Beil
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Postfach 3640, 76021 Karlsruhe, Germany
| | - Uwe Strähle
- Institute of Biological and Chemical Systems-Biological Information Processing (IBCS-BIP), Karlsruhe Institute of Technology (KIT), Postfach 3640, 76021 Karlsruhe, Germany
| | - Rudolf Merkel
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
| | - Bernd Hoffmann
- IBI-2: Mechanobiology, Institute of Biological Information Processing, Forschungszentrum Jülich, 52428 Jülich, Germany
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Schmitt LM, Dreissen G, Kolasinac R, Csiszár A, Merkel R. Membrane tension controls the phase equilibrium in fusogenic liposomes. RSC Adv 2022; 12:24114-24129. [PMID: 36093247 PMCID: PMC9400399 DOI: 10.1039/d2ra04019k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/15/2022] [Indexed: 11/21/2022] Open
Abstract
Fusogenic liposomes have been widely used for molecule delivery to cell membranes and cell interior. However, their physicochemical state is still little understood. We tested mechanical material behavior by micropipette aspiration of giant vesicles from fusogenic lipid mixtures and found that the membranes of these vesicles are fluid and under high mechanical tension even before aspiration. Based on this result, we developed a theoretical framework to determine the area expansion modulus and membrane tension of such pre-tensed vesicles from aspiration experiments. Surprisingly high membrane tension of 2.1 mN m-1 and very low area expansion modulus of 63 mN m-1 were found. We interpret these peculiar material properties as the result of a mechanically driven phase transition between the usual lamellar phase and an, as of now, not finally determined three dimensional phase of the lipid mixture. The free enthalpy of transition between these phases is very low, i.e. on the order of the thermal energy.
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Affiliation(s)
- Laura Maria Schmitt
- Forschungszentrum Julich, Institute of Biological Information Processing 2: MechanobiologyJulichGermany
| | - Georg Dreissen
- Forschungszentrum Julich, Institute of Biological Information Processing 2: MechanobiologyJulichGermany
| | - Rejhana Kolasinac
- Forschungszentrum Julich, Institute of Biological Information Processing 2: MechanobiologyJulichGermany
| | - Agnes Csiszár
- Forschungszentrum Julich, Institute of Biological Information Processing 2: MechanobiologyJulichGermany
| | - Rudolf Merkel
- Forschungszentrum Julich, Institute of Biological Information Processing 2: MechanobiologyJulichGermany+49 2461 613907+49 2461 613080
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Abraham JA, Blaschke S, Tarazi S, Dreissen G, Vay SU, Schroeter M, Fink GR, Merkel R, Rueger MA, Hoffmann B. NSCs Under Strain-Unraveling the Mechanoprotective Role of Differentiating Astrocytes in a Cyclically Stretched Coculture With Differentiating Neurons. Front Cell Neurosci 2021; 15:706585. [PMID: 34630042 PMCID: PMC8497758 DOI: 10.3389/fncel.2021.706585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 08/31/2021] [Indexed: 11/19/2022] Open
Abstract
The neural stem cell (NSC) niche is a highly vascularized microenvironment that supplies stem cells with relevant biological and chemical cues. However, the NSCs’ proximity to the vasculature also means that the NSCs are subjected to permanent tissue deformation effected by the vessels’ heartbeat-induced pulsatile movements. Cultivating NSCs under common culture conditions neglects the—yet unknown—influence of this cyclic mechanical strain on neural stem cells. Under the hypothesis that pulsatile strain should affect essential NSC functions, a cyclic uniaxial strain was applied under biomimetic conditions using an in-house developed stretching system based on cross-linked polydimethylsiloxane (PDMS) elastomer. While lineage commitment remained unaffected by cyclic deformation, strain affected NSC quiescence and cytoskeletal organization. Unexpectedly, cyclically stretched stem cells aligned in stretch direction, a phenomenon unknown for other types of cells in the mammalian organism. The same effect was observed for young astrocytes differentiating from NSCs. In contrast, young neurons differentiating from NSCs did not show mechanoresponsiveness. The exceptional orientation of NSCs and young astrocytes in the stretch direction was blocked upon RhoA activation and went along with a lack of stress fibers. Compared to postnatal astrocytes and mature neurons, NSCs and their young progeny displayed characteristic and distinct mechanoresponsiveness. Data suggest a protective role of young astrocytes in mixed cultures of differentiating neurons and astrocytes by mitigating the mechanical stress of pulsatile strain on developing neurons.
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Affiliation(s)
- Jella-Andrea Abraham
- Mechanobiology, Institute of Biological Information Processing (IBI-2), Research Centre Juelich, Juelich, Germany
| | - Stefan Blaschke
- Department of Neurology, Faculty of Medicine and University Hospital, University of Cologne, Cologne, Germany.,Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, Juelich, Germany
| | - Samar Tarazi
- Mechanobiology, Institute of Biological Information Processing (IBI-2), Research Centre Juelich, Juelich, Germany
| | - Georg Dreissen
- Mechanobiology, Institute of Biological Information Processing (IBI-2), Research Centre Juelich, Juelich, Germany
| | - Sabine U Vay
- Department of Neurology, Faculty of Medicine and University Hospital, University of Cologne, Cologne, Germany
| | - Michael Schroeter
- Department of Neurology, Faculty of Medicine and University Hospital, University of Cologne, Cologne, Germany.,Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, Juelich, Germany
| | - Gereon R Fink
- Department of Neurology, Faculty of Medicine and University Hospital, University of Cologne, Cologne, Germany.,Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, Juelich, Germany
| | - Rudolf Merkel
- Mechanobiology, Institute of Biological Information Processing (IBI-2), Research Centre Juelich, Juelich, Germany
| | - Maria A Rueger
- Department of Neurology, Faculty of Medicine and University Hospital, University of Cologne, Cologne, Germany.,Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, Juelich, Germany
| | - Bernd Hoffmann
- Mechanobiology, Institute of Biological Information Processing (IBI-2), Research Centre Juelich, Juelich, Germany
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Lövenich L, Dreissen G, Hoffmann C, Konrad J, Springer R, Höhfeld J, Merkel R, Hoffmann B. Strain induced mechanoresponse depends on cell contractility and BAG3-mediated autophagy. Mol Biol Cell 2021; 32:ar9. [PMID: 34379447 PMCID: PMC8684750 DOI: 10.1091/mbc.e21-05-0254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Basically all mammalian tissues are constantly exposed to a variety of environmental mechanical signals. Depending on the signal strength, mechanics intervenes in a multitude of cellular processes and is thus capable to induce simple cellular adaptations but also complex differentiation processes and even apoptosis. The underlying recognition typically depends on mechanosensitive proteins, which most often sense the mechanical signal for the induction of a cellular signaling cascade by changing their protein conformation. However, the fate of mechanosensors after mechanical stress application is still poorly understood and it remains unclear whether protein degradation pathways affect the mechanosensitivity of cells. Here, we show that cyclic stretch induces autophagosome formation in a time-dependent manner. Formation depends on the cochaperone BAG3 and thus likely involves BAG3-mediated chaperone-assisted selective autophagy. Furthermore, we demonstrate that strain-induced cell reorientation is clearly delayed upon inhibition of autophagy, suggesting a bidirectional crosstalk between mechanotransduction and autophagic degradation. The strength of the observed delay depends on stable adhesion structures and stress fiber formation in a RhoA-dependent manner.
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Affiliation(s)
- Lukas Lövenich
- Forschungszentrum Jülich, Institute of Biological Information Processing, IBI-2: Mechanobiology, 52428 Jülich, Germany
| | - Georg Dreissen
- Forschungszentrum Jülich, Institute of Biological Information Processing, IBI-2: Mechanobiology, 52428 Jülich, Germany
| | - Christina Hoffmann
- Forschungszentrum Jülich, Institute of Biological Information Processing, IBI-2: Mechanobiology, 52428 Jülich, Germany
| | - Jens Konrad
- Forschungszentrum Jülich, Institute of Biological Information Processing, IBI-2: Mechanobiology, 52428 Jülich, Germany
| | - Ronald Springer
- Forschungszentrum Jülich, Institute of Biological Information Processing, IBI-2: Mechanobiology, 52428 Jülich, Germany
| | - Jörg Höhfeld
- Institute for Cell Biology, University of Bonn, 53121 Bonn, Germany
| | - Rudolf Merkel
- Forschungszentrum Jülich, Institute of Biological Information Processing, IBI-2: Mechanobiology, 52428 Jülich, Germany
| | - Bernd Hoffmann
- Forschungszentrum Jülich, Institute of Biological Information Processing, IBI-2: Mechanobiology, 52428 Jülich, Germany
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Eschenbruch J, Dreissen G, Springer R, Konrad J, Merkel R, Hoffmann B, Noetzel E. From Microspikes to Stress Fibers: Actin Remodeling in Breast Acini Drives Myosin II-Mediated Basement Membrane Invasion. Cells 2021; 10:cells10081979. [PMID: 34440749 PMCID: PMC8394122 DOI: 10.3390/cells10081979] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/22/2021] [Accepted: 07/27/2021] [Indexed: 12/12/2022] Open
Abstract
The cellular mechanisms of basement membrane (BM) invasion remain poorly understood. We investigated the invasion-promoting mechanisms of actin cytoskeleton reorganization in BM-covered MCF10A breast acini. High-resolution confocal microscopy has characterized actin cell protrusion formation and function in response to tumor-resembling ECM stiffness and soluble EGF stimulation. Traction force microscopy quantified the mechanical BM stresses that invasion-triggered acini exerted on the BM-ECM interface. We demonstrate that acini use non-proteolytic actin microspikes as functional precursors of elongated protrusions to initiate BM penetration and ECM probing. Further, these microspikes mechanically widened the collagen IV pores to anchor within the BM scaffold via force-transmitting focal adhesions. Pre-invasive basal cells located at the BM-ECM interface exhibited predominantly cortical actin networks and actin microspikes. In response to pro-invasive conditions, these microspikes accumulated and converted subsequently into highly contractile stress fibers. The phenotypical switch to stress fiber cells matched spatiotemporally with emerging high BM stresses that were driven by actomyosin II contractility. The activation of proteolytic invadopodia with MT1-MMP occurred at later BM invasion stages and only in cells already disseminating into the ECM. Our study demonstrates that BM pore-widening filopodia bridge mechanical ECM probing function and contractility-driven BM weakening. Finally, these EMT-related cytoskeletal adaptations are critical mechanisms inducing the invasive transition of benign breast acini.
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Sridhar KC, Hersch N, Dreissen G, Merkel R, Hoffmann B. Calcium mediated functional interplay between myocardial cells upon laser-induced single-cell injury: an in vitro study of cardiac cell death signaling mechanisms. Cell Commun Signal 2020; 18:191. [PMID: 33371897 PMCID: PMC7771078 DOI: 10.1186/s12964-020-00689-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 11/23/2020] [Indexed: 01/09/2023] Open
Abstract
Background The electromechanical function of myocardial tissue depends on the intercellular communication between cardiomyocytes (CMs) as well as their crosstalk with other cell types. Cell injury, and subsequent death trigger inflammation as in myocardial infarction (MI) resulting in myocardial remodeling. Although mechanisms underlying myocardial cell death have been studied so far, the signaling events following single cell death and spontaneous response of connected cells in the myocardial tissue is still barely understood. Methods Here, we investigated the effect of laser-induced single cell death on Calcium (Ca2+) concentrations and transport in myocardial cell clusters in vitro. Spatial and temporal changes in intracellular Ca2+ concentrations [Ca2+]i were studied using a fluorescent calcium indicator, Fluo-4AM. Spontaneous signaling events following cell death were studied in rat embryonic cardiomyocytes and non-myocytes using separate cell culture systems. Results Cell death triggered spontaneous increase in intracellular Ca2+ levels ([Ca2+]i) of surrounding cells. The spread of the observed propagating Ca2+ signal was slow and sustained in myocytes while it was rapid and transient in fibroblasts (Fbs). Further, sustained high Ca2+ levels temporarily impaired the contractility in CMs. The cell-type specific effect of ablation was confirmed using separate cultures of CMs and Fbs. Comparing Ca2+ propagation speed in myocytes and fibroblasts, we argue for a diffusion-driven Ca2+ propagation in myocytes, but not in fibroblasts. Radial and sequential Ca2+ diffusion across the CMs through cell–cell contacts and presence of Cx43-based intercellular junctions indicated a gap junction flow of Ca2+. Conclusions These findings illustrate the spontaneous Ca2+-mediated functional interplay in myocardial cell clusters upon mechanical injury and, further, the difference in Ca2+ signaling in cardiomyocytes and fibroblasts. Video Abstract
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Affiliation(s)
- Krishna Chander Sridhar
- Institute of Biological Information Processing, IBI-2: Mechanobiology, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Nils Hersch
- Institute of Biological Information Processing, IBI-2: Mechanobiology, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Georg Dreissen
- Institute of Biological Information Processing, IBI-2: Mechanobiology, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Rudolf Merkel
- Institute of Biological Information Processing, IBI-2: Mechanobiology, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Bernd Hoffmann
- Institute of Biological Information Processing, IBI-2: Mechanobiology, Forschungszentrum Jülich, 52425, Jülich, Germany.
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Pora A, Yoon S, Dreissen G, Hoffmann B, Merkel R, Windoffer R, Leube RE. Regulation of keratin network dynamics by the mechanical properties of the environment in migrating cells. Sci Rep 2020; 10:4574. [PMID: 32165652 PMCID: PMC7067805 DOI: 10.1038/s41598-020-61242-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 02/24/2020] [Indexed: 01/19/2023] Open
Abstract
Keratin intermediate filaments provide mechanical resilience for epithelia. They are nevertheless highly dynamic and turn over continuously, even in sessile keratinocytes. The aim of this study was to characterize and understand how the dynamic behavior of the keratin cytoskeleton is integrated in migrating cells. By imaging human primary keratinocytes producing fluorescent reporters and by using standardized image analysis we detect inward-directed keratin flow with highest rates in the cell periphery. The keratin flow correlates with speed and trajectory of migration. Changes in fibronectin-coating density and substrate stiffness induces concordant changes in migration speed and keratin flow. When keratinocytes are pseudo-confined on stripes, migration speed and keratin flow are reduced affecting the latter disproportionately. The regulation of keratin flow is linked to the regulation of actin flow. Local speed and direction of keratin and actin flow are very similar in migrating keratinocytes with keratin flow lagging behind actin flow. Conversely, reduced actin flow in areas of high keratin density indicates an inhibitory function of keratins on actin dynamics. Together, we propose that keratins enhance persistence of migration by directing actin dynamics and that the interplay of keratin and actin dynamics is modulated by matrix adhesions.
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Affiliation(s)
- Anne Pora
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, 52074, Aachen, Germany
| | - Sungjun Yoon
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, 52074, Aachen, Germany
| | - Georg Dreissen
- Institute of Biological Information Processing 2, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Bernd Hoffmann
- Institute of Biological Information Processing 2, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Rudolf Merkel
- Institute of Biological Information Processing 2, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Reinhard Windoffer
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, 52074, Aachen, Germany
| | - Rudolf E Leube
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, 52074, Aachen, Germany.
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Kolašinac R, Jaksch S, Dreissen G, Braeutigam A, Merkel R, Csiszár A. Influence of Environmental Conditions on the Fusion of Cationic Liposomes with Living Mammalian Cells. Nanomaterials (Basel) 2019; 9:nano9071025. [PMID: 31319557 PMCID: PMC6669649 DOI: 10.3390/nano9071025] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/12/2019] [Accepted: 07/12/2019] [Indexed: 12/12/2022]
Abstract
Lipid-based nanoparticles, also called vesicles or liposomes, can be used as carriers for drugs or many types of biological macromolecules, including DNA and proteins. Efficiency and speed of cargo delivery are especially high for carrier vesicles that fuse with the cellular plasma membrane. This occurs for lipid mixture containing equal amounts of the cationic lipid DOTAP and a neutral lipid with an additional few percents of an aromatic substance. The fusion ability of such particles depends on lipid composition with phosphoethanolamine (PE) lipids favoring fusion and phosphatidyl-choline (PC) lipids endocytosis. Here, we examined the effects of temperature, ionic strength, osmolality, and pH on fusion efficiency of cationic liposomes with Chinese hamster ovary (CHO) cells. The phase state of liposomes was analyzed by small angle neutron scattering (SANS). Our results showed that PC containing lipid membranes were organized in the lamellar phase. Here, fusion efficiency depended on buffer conditions and remained vanishingly small at physiological conditions. In contrast, SANS indicated the coexistence of very small (~50 nm) objects with larger, most likely lamellar structures for PE containing lipid particles. The fusion of such particles to cell membranes occurred with very high efficiency at all buffer conditions. We hypothesize that the altered phase state resulted in a highly reduced energetic barrier against fusion.
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Affiliation(s)
- Rejhana Kolašinac
- Forschungszentrum Jülich GmbH, Institute of Complex Systems: ICS-7 Biomechanics, 52428 Jülich, Germany
| | - Sebastian Jaksch
- Forschungszentrum Jülich GmbH, Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), 85748 Garching, Germany
| | - Georg Dreissen
- Forschungszentrum Jülich GmbH, Institute of Complex Systems: ICS-7 Biomechanics, 52428 Jülich, Germany
| | - Andrea Braeutigam
- Forschungszentrum Jülich GmbH, Institute of Complex Systems: ICS-2 Theoretical Soft Matter and Biophysics, 52428 Jülich, Germany
| | - Rudolf Merkel
- Forschungszentrum Jülich GmbH, Institute of Complex Systems: ICS-7 Biomechanics, 52428 Jülich, Germany
| | - Agnes Csiszár
- Forschungszentrum Jülich GmbH, Institute of Complex Systems: ICS-7 Biomechanics, 52428 Jülich, Germany.
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Abraham JA, Linnartz C, Dreissen G, Springer R, Blaschke S, Rueger MA, Fink GR, Hoffmann B, Merkel R. Directing Neuronal Outgrowth and Network Formation of Rat Cortical Neurons by Cyclic Substrate Stretch. Langmuir 2019; 35:7423-7431. [PMID: 30110535 DOI: 10.1021/acs.langmuir.8b02003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Neuronal mechanobiology plays a vital function in brain development and homeostasis with an essential role in neuronal maturation, pathfinding, and differentiation but is also crucial for understanding brain pathology. In this study, we constructed an in vitro system to assess neuronal responses to cyclic strain as a mechanical signal. The selected strain amplitudes mimicked physiological as well as pathological conditions. By subjecting embryonic neuronal cells to cyclic uniaxial strain we could steer the direction of neuronal outgrowth perpendicular to strain direction for all applied amplitudes. A long-term analysis proved maintained growth direction. Moreover, stretched neurons showed an enhanced length, growth, and formation of nascent side branches with most elevated growth rates subsequent to physiological straining. Application of cyclic strain to already formed neurites identified retraction bulbs with destabilized microtubule structures as spontaneous responses. Importantly, neurons were able to adapt to the mechanical signals without induction of cell death and showed a triggered growth behavior when compared to unstretched neurons. The data suggest that cyclic strain plays a critical role in neuronal development.
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Affiliation(s)
- Jella-Andrea Abraham
- Institute of Complex Systems (ICS-7): Biomechanics , Research Centre Jülich , Jülich 52425 , Germany
| | - Christina Linnartz
- Institute of Complex Systems (ICS-7): Biomechanics , Research Centre Jülich , Jülich 52425 , Germany
| | - Georg Dreissen
- Institute of Complex Systems (ICS-7): Biomechanics , Research Centre Jülich , Jülich 52425 , Germany
| | - Ronald Springer
- Institute of Complex Systems (ICS-7): Biomechanics , Research Centre Jülich , Jülich 52425 , Germany
| | - Stefan Blaschke
- Department of Neurology , University Hospital of Cologne , Cologne 50937 , Germany
- Institute of Neuroscience and Medicine (INM-3): Cognitive Neuroscience , Research Centre Jülich , Jülich 52425 , Germany
| | - Maria A Rueger
- Department of Neurology , University Hospital of Cologne , Cologne 50937 , Germany
- Institute of Neuroscience and Medicine (INM-3): Cognitive Neuroscience , Research Centre Jülich , Jülich 52425 , Germany
| | - Gereon R Fink
- Department of Neurology , University Hospital of Cologne , Cologne 50937 , Germany
- Institute of Neuroscience and Medicine (INM-3): Cognitive Neuroscience , Research Centre Jülich , Jülich 52425 , Germany
| | - Bernd Hoffmann
- Institute of Complex Systems (ICS-7): Biomechanics , Research Centre Jülich , Jülich 52425 , Germany
| | - Rudolf Merkel
- Institute of Complex Systems (ICS-7): Biomechanics , Research Centre Jülich , Jülich 52425 , Germany
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Zielinski A, Linnartz C, Pleschka C, Dreissen G, Springer R, Merkel R, Hoffmann B. Reorientation dynamics and structural interdependencies of actin, microtubules and intermediate filaments upon cyclic stretch application. Cytoskeleton (Hoboken) 2018; 75:385-394. [DOI: 10.1002/cm.21470] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 05/18/2018] [Accepted: 06/01/2018] [Indexed: 12/17/2022]
Affiliation(s)
- Alexander Zielinski
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics; Jülich Germany
| | - Christina Linnartz
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics; Jülich Germany
| | - Catharina Pleschka
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics; Jülich Germany
| | - Georg Dreissen
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics; Jülich Germany
| | - Ronald Springer
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics; Jülich Germany
| | - Rudolf Merkel
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics; Jülich Germany
| | - Bernd Hoffmann
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics; Jülich Germany
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12
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Noethel B, Ramms L, Dreissen G, Hoffmann M, Springer R, Rübsam M, Ziegler WH, Niessen CM, Merkel R, Hoffmann B. Transition of responsive mechanosensitive elements from focal adhesions to adherens junctions on epithelial differentiation. Mol Biol Cell 2018; 29:2317-2325. [PMID: 30044710 PMCID: PMC6249805 DOI: 10.1091/mbc.e17-06-0387] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The skin’s epidermis is a multilayered epithelial tissue and the first line of defense against mechanical stress. Its barrier function depends on an integrated assembly and reorganization of cell–matrix and cell–cell junctions in the basal layer and on different intercellular junctions in suprabasal layers. However, how mechanical stress is recognized and which adhesive and cytoskeletal components are involved are poorly understood. Here, we subjected keratinocytes to cyclic stress in the presence or absence of intercellular junctions. Both states not only recognized but also responded to strain by reorienting actin filaments perpendicular to the applied force. Using different keratinocyte mutant strains that altered the mechanical link of the actin cytoskeleton to either cell–matrix or cell–cell junctions, we show that not only focal adhesions but also adherens junctions function as mechanosensitive elements in response to cyclic strain. Loss of paxillin or talin impaired focal adhesion formation and only affected mechanosensitivity in the absence but not presence of intercellular junctions. Further analysis revealed the adherens junction protein α-catenin as a main mechanosensor, with greatest sensitivity conferred on binding to vinculin. Our data reveal a mechanosensitive transition from cell–matrix to cell–cell adhesions on formation of keratinocyte monolayers with vinculin and α-catenin as vital players.
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Affiliation(s)
- Barbara Noethel
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics, 52428 Jülich, Germany
| | - Lena Ramms
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics, 52428 Jülich, Germany
| | - Georg Dreissen
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics, 52428 Jülich, Germany
| | - Marco Hoffmann
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics, 52428 Jülich, Germany
| | - Ronald Springer
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics, 52428 Jülich, Germany
| | - Matthias Rübsam
- Department of Dermatology, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
| | - Wolfgang H Ziegler
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, 30625 Hannover, Germany
| | - Carien M Niessen
- Department of Dermatology, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Center for Molecular Medicine Cologne, University of Cologne, 50931 Cologne, Germany
| | - Rudolf Merkel
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics, 52428 Jülich, Germany
| | - Bernd Hoffmann
- Forschungszentrum Jülich, Institute of Complex Systems, ICS-7: Biomechanics, 52428 Jülich, Germany
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Kugler EM, Michel K, Kirchenbüchler D, Dreissen G, Csiszár A, Merkel R, Schemann M, Mazzuoli-Weber G. Sensitivity to Strain and Shear Stress of Isolated Mechanosensitive Enteric Neurons. Neuroscience 2018; 372:213-224. [PMID: 29317262 DOI: 10.1016/j.neuroscience.2017.12.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 12/20/2017] [Accepted: 12/27/2017] [Indexed: 10/18/2022]
Abstract
Within the enteric nervous system, the neurons in charge to control motility of the gastrointestinal tract reside in a particular location nestled between two perpendicular muscle layers which contract and relax. We used primary cultured myenteric neurons of male guinea pigs to study mechanosensitivity of enteric neurons in isolation. Ultrafast Neuroimaging with a voltage-sensitive dye technique was used to record neuronal activity in response to shear stress and strain. Strain was induced by locally deforming the elastic cell culture substrate next to a neuron. Measurements showed that substrate strain was mostly elongating cells. Shear stress was exerted by hydrodynamic forces in a microchannel. Both stimuli induced excitatory responses. Strain activated 14% of the stimulated myenteric neurons that responded with a spike frequency of 1.9 (0.7/3.2) Hz, whereas shear stress excited only a few neurons (5.6%) with a very low spike frequency of 0 (0/0.6) Hz. Thus, shear stress does not seem to be an adequate stimulus for mechanosensitive enteric neurons (MEN) while strain activates enteric neurons in a relevant manner. Analyzing the adaptation behavior of MEN showed that shear stress activated rapidly/slowly/ultraslowly adapting MEN (2/62/36%) whereas strain only slowly (46%) and ultraslowly (54%) MEN. Paired experiments with strain and normal stress revealed three mechanosensitive enteric neuronal populations: one strain-sensitive (37%), one normal stress-sensitive (17%) and one strain- and stress-sensitive (46%). These results indicate that shear stress does not play a role in the neuronal control of motility but normal stress and strain.
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Affiliation(s)
- Eva Maria Kugler
- Human Biology, Technische Universität München, Freising-Weihenstephan, 85354, Germany.
| | - Klaus Michel
- Human Biology, Technische Universität München, Freising-Weihenstephan, 85354, Germany.
| | - David Kirchenbüchler
- Institute of Complex Systems - Biomechanics, Research Center Jülich, 52425 Jülich, Germany.
| | - Georg Dreissen
- Institute of Complex Systems - Biomechanics, Research Center Jülich, 52425 Jülich, Germany.
| | - Agnes Csiszár
- Institute of Complex Systems - Biomechanics, Research Center Jülich, 52425 Jülich, Germany.
| | - Rudolf Merkel
- Institute of Complex Systems - Biomechanics, Research Center Jülich, 52425 Jülich, Germany.
| | - Michael Schemann
- Human Biology, Technische Universität München, Freising-Weihenstephan, 85354, Germany.
| | - Gemma Mazzuoli-Weber
- Human Biology, Technische Universität München, Freising-Weihenstephan, 85354, Germany.
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14
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Abstract
Animal cells use traction forces to sense the mechanics and geometry of their environment. Measuring these traction forces requires a workflow combining cell experiments, image processing and force reconstruction based on elasticity theory. Such procedures have already been established mainly for planar substrates, in which case one can use the Green's function formalism. Here we introduce a workflow to measure traction forces of cardiac myofibroblasts on non-planar elastic substrates. Soft elastic substrates with a wave-like topology were micromoulded from polydimethylsiloxane and fluorescent marker beads were distributed homogeneously in the substrate. Using feature vector-based tracking of these marker beads, we first constructed a hexahedral mesh for the substrate. We then solved the direct elastic boundary volume problem on this mesh using the finite-element method. Using data simulations, we show that the traction forces can be reconstructed from the substrate deformations by solving the corresponding inverse problem with an L1-norm for the residue and an L2-norm for a zeroth-order Tikhonov regularization. Applying this procedure to the experimental data, we find that cardiac myofibroblast cells tend to align both their shapes and their forces with the long axis of the deformable wavy substrate.
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Affiliation(s)
- Jérôme R. D. Soiné
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany
- BioQuant, Heidelberg University, Heidelberg, Germany
| | - Nils Hersch
- Institute of Complex Systems 7: Biomechanics, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Georg Dreissen
- Institute of Complex Systems 7: Biomechanics, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Nico Hampe
- Institute of Complex Systems 7: Biomechanics, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Bernd Hoffmann
- Institute of Complex Systems 7: Biomechanics, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Rudolf Merkel
- Institute of Complex Systems 7: Biomechanics, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Ulrich S. Schwarz
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany
- BioQuant, Heidelberg University, Heidelberg, Germany
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15
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Gaiko-Shcherbak A, Fabris G, Dreissen G, Merkel R, Hoffmann B, Noetzel E. The Acinar Cage: Basement Membranes Determine Molecule Exchange and Mechanical Stability of Human Breast Cell Acini. PLoS One 2015; 10:e0145174. [PMID: 26674091 PMCID: PMC4684506 DOI: 10.1371/journal.pone.0145174] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/30/2015] [Indexed: 11/19/2022] Open
Abstract
The biophysical properties of the basement membrane that surrounds human breast glands are poorly understood, but are thought to be decisive for normal organ function and malignancy. Here, we characterize the breast gland basement membrane with a focus on molecule permeation and mechanical stability, both crucial for organ function. We used well-established and nature-mimicking MCF10A acini as 3D cell model for human breast glands, with ether low- or highly-developed basement membrane scaffolds. Semi-quantitative dextran tracer (3 to 40 kDa) experiments allowed us to investigate the basement membrane scaffold as a molecule diffusion barrier in human breast acini in vitro. We demonstrated that molecule permeation correlated positively with macromolecule size and intriguingly also with basement membrane development state, revealing a pore size of at least 9 nm. Notably, an intact collagen IV mesh proved to be essential for this permeation function. Furthermore, we performed ultra-sensitive atomic force microscopy to quantify the response of native breast acini and of decellularized basement membrane shells against mechanical indentation. We found a clear correlation between increasing acinar force resistance and basement membrane formation stage. Most important native acini with highly-developed basement membranes as well as cell-free basement membrane shells could both withstand physiologically relevant loads (≤ 20 nN) without loss of structural integrity. In contrast, low-developed basement membranes were significantly softer and more fragile. In conclusion, our study emphasizes the key role of the basement membrane as conductor of acinar molecule influx and mechanical stability of human breast glands, which are fundamental for normal organ function.
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Affiliation(s)
- Aljona Gaiko-Shcherbak
- Institute of Complex Systems ICS7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
| | - Gloria Fabris
- Institute of Complex Systems ICS7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
| | - Georg Dreissen
- Institute of Complex Systems ICS7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
| | - Rudolf Merkel
- Institute of Complex Systems ICS7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
| | - Bernd Hoffmann
- Institute of Complex Systems ICS7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
| | - Erik Noetzel
- Institute of Complex Systems ICS7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
- * E-mail:
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16
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Homberg M, Ramms L, Schwarz N, Dreissen G, Leube RE, Merkel R, Hoffmann B, Magin TM. Distinct Impact of Two Keratin Mutations Causing Epidermolysis Bullosa Simplex on Keratinocyte Adhesion and Stiffness. J Invest Dermatol 2015; 135:2437-2445. [DOI: 10.1038/jid.2015.184] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 04/10/2015] [Accepted: 04/25/2015] [Indexed: 12/20/2022]
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17
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Kugler E, Michel K, Kirchenbüchler D, Dreissen G, Merkel R, Schemann M, Mazzuoli G. Physiological mechanical stimulation activates isolated myenteric neurons. Auton Neurosci 2013. [DOI: 10.1016/j.autneu.2013.05.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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18
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Hersch N, Wolters B, Dreissen G, Springer R, Kirchgeßner N, Merkel R, Hoffmann B. The constant beat: cardiomyocytes adapt their forces by equal contraction upon environmental stiffening. Biol Open 2013; 2:351-61. [PMID: 23519595 PMCID: PMC3603417 DOI: 10.1242/bio.20133830] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 12/23/2012] [Indexed: 12/25/2022] Open
Abstract
Cardiomyocytes are responsible for the permanent blood flow by coordinated heart contractions. This vital function is accomplished over a long period of time with almost the same performance, although heart properties, as its elasticity, change drastically upon aging or as a result of diseases like myocardial infarction. In this paper we have analyzed late rat embryonic heart muscle cells' morphology, sarcomere/costamere formation and force generation patterns on substrates of various elasticities ranging from ∼1 to 500 kPa, which covers physiological and pathological heart stiffnesses. Furthermore, adhesion behaviour, as well as single myofibril/sarcomere contraction patterns, was characterized with high spatial resolution in the range of physiological stiffnesses (15 kPa to 90 kPa). Here, sarcomere units generate an almost stable contraction of ∼4%. On stiffened substrates the contraction amplitude remains stable, which in turn leads to increased force levels allowing cells to adapt almost instantaneously to changing environmental stiffness. Furthermore, our data strongly indicate specific adhesion to flat substrates via both costameric and focal adhesions. The general appearance of the contractile and adhesion apparatus remains almost unaffected by substrate stiffness.
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Affiliation(s)
- Nils Hersch
- Institute of Complex Systems, ICS-7: Biomechanics, Forschungszentrum Jülich GmbH , 52425 Jülich , Germany
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Zielinski A, Hoffmann B, Springer R, Dreissen G, Merkel R. Stressed Stress Fibers. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.1760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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20
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Hersch N, Dreissen G, Springer R, Kirchgessner N, Hoffmann B, Merkel R. Dependence of Forces and Ahdesion Structures of Primary Myocytes on Substrate Elasticity. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.1903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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21
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Jansen M, Gilmer F, Biskup B, Nagel KA, Rascher U, Fischbach A, Briem S, Dreissen G, Tittmann S, Braun S, De Jaeger I, Metzlaff M, Schurr U, Scharr H, Walter A. Simultaneous phenotyping of leaf growth and chlorophyll fluorescence via GROWSCREEN FLUORO allows detection of stress tolerance in Arabidopsis thaliana and other rosette plants. Funct Plant Biol 2009; 36:902-914. [PMID: 32688701 DOI: 10.1071/fp09095] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 08/03/2009] [Indexed: 05/27/2023]
Abstract
Stress caused by environmental factors evokes dynamic changes in plant phenotypes. In this study, we deciphered simultaneously the reaction of plant growth and chlorophyll fluorescence related parameters using a novel approach which combines existing imaging technologies (GROWSCREEN FLUORO). Three different abiotic stress situations were investigated demonstrating the benefit of this approach to distinguish between effects related to (1) growth, (2) chlorophyll-fluorescence, or (3) both of these aspects of the phenotype. In a drought stress experiment with more than 500 plants, poly(ADP-ribose) polymerase (PARP) deficient lines of Arabidopsis thaliana (L.) Heynh showed increased relative growth rates (RGR) compared with C24 wild-type plants. In chilling stress, growth of PARP and C24 lines decreased rapidly, followed by a decrease in Fv/Fm. Here, PARP-plants showed a more pronounced decrease of Fv/Fm than C24, which can be interpreted as a more efficient strategy for survival in mild chilling stress. Finally, the reaction of Nicotiana tabacum L. to altered spectral composition of the intercepted light was monitored as an example of a moderate stress situation that affects chlorophyll-fluorescence related, but not growth-related parameters. The examples investigated in this study show the capacity for improved plant phenotyping based on an automated and simultaneous evaluation of growth and photosynthesis at high throughput.
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Affiliation(s)
- Marcus Jansen
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Frank Gilmer
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Bernhard Biskup
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Kerstin A Nagel
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Uwe Rascher
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Andreas Fischbach
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Sabine Briem
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Georg Dreissen
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Susanne Tittmann
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Silvia Braun
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Iris De Jaeger
- Bayer BioScience N.V., Technologiepark 38, 9052 Gent, Belgium
| | | | - Ulrich Schurr
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Hanno Scharr
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Achim Walter
- Institute of Chemistry and Dynamics of the Geosphere ICG-3 (Phytosphere), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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