1
|
Peterson BE, Rolfe RA, Kunselman A, Murphy P, Szczesny SE. Mechanical Stimulation via Muscle Activity Is Necessary for the Maturation of Tendon Multiscale Mechanics During Embryonic Development. Front Cell Dev Biol 2021; 9:725563. [PMID: 34540841 PMCID: PMC8446456 DOI: 10.3389/fcell.2021.725563] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/16/2021] [Indexed: 11/17/2022] Open
Abstract
During embryonic development, tendons transform into a hypocellular tissue with robust tensile load-bearing capabilities. Previous work suggests that this mechanical transformation is due to increases in collagen fibril length and is dependent on mechanical stimulation via muscle activity. However, the relationship between changes in the microscale tissue structure and changes in macroscale tendon mechanics is still unclear. Additionally, the specific effect of mechanical stimulation on the multiscale structure-function relationships of developing tendons is also unknown. Therefore, the objective of this study was to measure the changes in tendon mechanics and structure at multiple length scales during embryonic development with and without skeletal muscle paralysis. Tensile testing of tendons from chick embryos was performed to determine the macroscale tensile modulus as well as the magnitude of the fibril strains and interfibrillar sliding with applied tissue strain. Embryos were also treated with either decamethonium bromide or pancuronium bromide to produce rigid or flaccid paralysis. Histology was performed to assess changes in tendon size, spacing between tendon subunits, and collagen fiber diameter. We found that the increase in the macroscale modulus observed with development is accompanied by an increase in the fibril:tissue strain ratio, which is consistent with an increase in collagen fibril length. Additionally, we found that flaccid paralysis reduced the macroscale tendon modulus and the fibril:tissue strain ratio, whereas less pronounced effects that were not statistically significant were observed with rigid paralysis. Finally, skeletal paralysis also reduced the size of collagen fibril bundles (i.e., fibers). Together, these data suggest that more of the applied tissue strain is transmitted to the collagen fibrils at later embryonic ages, which leads to an increase in the tendon macroscale tensile mechanics. Furthermore, our data suggest that mechanical stimulation during development is necessary to induce structural and mechanical changes at multiple physical length scales. This information provides valuable insight into the multiscale structure-function relationships of developing tendons and the importance of mechanical stimulation in producing a robust tensile load-bearing soft tissue.
Collapse
Affiliation(s)
- Benjamin E Peterson
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, United States
| | - Rebecca A Rolfe
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, The University of Dublin, Dublin, Ireland
| | - Allen Kunselman
- Department of Public Health Science, Division of Biostatistics and Bioinformatics, Pennsylvania State University, Hershey, PA, United States
| | - Paula Murphy
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, The University of Dublin, Dublin, Ireland
| | - Spencer E Szczesny
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA, United States.,Department of Orthopaedics and Rehabilitation, Pennsylvania State University, Hershey, PA, United States
| |
Collapse
|
2
|
Rolfe RA, Bezer JH, Kim T, Zaidon AZ, Oyen ML, Iatridis JC, Nowlan NC. Abnormal fetal muscle forces result in defects in spinal curvature and alterations in vertebral segmentation and shape. J Orthop Res 2017; 35:2135-2144. [PMID: 28079273 PMCID: PMC5523455 DOI: 10.1002/jor.23518] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 01/06/2017] [Indexed: 02/04/2023]
Abstract
The incidence of congenital spine deformities, including congenital scoliosis, kyphosis, and lordosis, may be influenced by the in utero mechanical environment, and particularly by fetal movements at critical time-points. There is a limited understanding of the influence of fetal movements on spinal development, despite the fact that mechanical forces have been shown to play an essential role in skeletal development of the limb. This study investigates the effects of muscle forces on spinal curvature, vertebral segmentation, and vertebral shape by inducing rigid or flaccid paralysis in the embryonic chick. The critical time-points for the influence of fetal movements on spinal development were identified by varying the time of onset of paralysis. Prolonged rigid paralysis induced severe defects in the spine, including curvature abnormalities, posterior and anterior vertebral fusions, and altered vertebral shape, while flaccid paralysis did not affect spinal curvature or vertebral segmentation. Early rigid paralysis resulted in more severe abnormalities in the spine than later rigid paralysis. The findings of this study support the hypothesis that the timing and nature of fetal muscle activity are critical influences on the normal development of the spine, with implications for the understanding of congenital spine deformities. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2135-2144, 2017.
Collapse
Affiliation(s)
- Rebecca A. Rolfe
- Department of Bioengineering, Imperial College London, London,
United Kingdom
| | - James H. Bezer
- Department of Bioengineering, Imperial College London, London,
United Kingdom
| | - Tyler Kim
- Department of Bioengineering, Imperial College London, London,
United Kingdom
| | - Ahmed Z. Zaidon
- Department of Bioengineering, Imperial College London, London,
United Kingdom
| | - Michelle L. Oyen
- Engineering Department, University of Cambridge, Cambridge, United
Kingdom
| | - James C. Iatridis
- Department of Orthopaedics, Icahn School of Medicine at Mount Sinai,
New York, NY 10029
| | - Niamh C. Nowlan
- Department of Bioengineering, Imperial College London, London,
United Kingdom,Correspondence: Dr Niamh Nowlan, Phone: +44 (0)
20 759 45189,
| |
Collapse
|
3
|
Nowlan NC, Chandaria V, Sharpe J. Immobilized chicks as a model system for early-onset developmental dysplasia of the hip. J Orthop Res 2014; 32:777-85. [PMID: 24590854 DOI: 10.1002/jor.22606] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 02/03/2014] [Indexed: 02/04/2023]
Abstract
We have almost no understanding of how our joints take on their range of distinctive shapes, despite the clinical relevance of joint morphogenesis to postnatal skeletal malformations such as developmental dysplasia of the hip (DDH). In this study, we investigate the role of spontaneous prenatal movements in joint morphogenesis using pharmacological immobilization of developing chicks, and assess the system as a suitable model for early-onset hip dysplasia. We show that, prior to joint cavitation, the lack of dynamic muscle contractions has little impact on the shape of the hip joint. However, after the timepoint at which cavitation occurs, a dramatic effect on hip joint morphogenesis was observed. Effects in the immobilized chicks included flattening of the proximal femur, abnormal orientation of the pelvis relative to the femur and abnormal placement and coverage of the acetabulum. Although many clinical case studies have identified reduced or restricted movement as a risk factor for DDH, this study provides the first experimental evidence of the role of prenatal movements in early hip joint development. We propose that the immobilized chick embryo serves as a suitable model system for the type of early-onset DDH which arises due to neuromuscular conditions such as spinal muscular atrophy.
Collapse
Affiliation(s)
- Niamh C Nowlan
- EMBL-CRG Systems Biology Program, Centre for Genomic Regulation, UPF, Dr. Aiguader 88, 08003, Barcelona, Spain; Department of Bioengineering, Imperial College London, London, United Kingdom
| | | | | |
Collapse
|
4
|
Abstract
Morphogenesis is the remarkable process by which cells self-assemble into complex tissues and organs that exhibit specialized form and function during embryological development. Many of the genes and chemical cues that mediate tissue and organ formation have been identified; however, these signals alone are not sufficient to explain how tissues and organs are constructed that exhibit their unique material properties and three-dimensional forms. Here, we review work that has revealed the central role that physical forces and extracellular matrix mechanics play in the control of cell fate switching, pattern formation, and tissue development in the embryo and how these same mechanical signals contribute to tissue homeostasis and developmental control throughout adult life.
Collapse
Affiliation(s)
- Tadanori Mammoto
- Vascular Biology Program, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115;
| | | | | |
Collapse
|
5
|
Mechanical influences on morphogenesis of the knee joint revealed through morphological, molecular and computational analysis of immobilised embryos. PLoS One 2011; 6:e17526. [PMID: 21386908 PMCID: PMC3046254 DOI: 10.1371/journal.pone.0017526] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 02/03/2011] [Indexed: 11/19/2022] Open
Abstract
Very little is known about the regulation of morphogenesis in synovial joints. Mechanical forces generated from muscle contractions are required for normal development of several aspects of normal skeletogenesis. Here we show that biophysical stimuli generated by muscle contractions impact multiple events during chick knee joint morphogenesis influencing differential growth of the skeletal rudiment epiphyses and patterning of the emerging tissues in the joint interzone. Immobilisation of chick embryos was achieved through treatment with the neuromuscular blocking agent Decamethonium Bromide. The effects on development of the knee joint were examined using a combination of computational modelling to predict alterations in biophysical stimuli, detailed morphometric analysis of 3D digital representations, cell proliferation assays and in situ hybridisation to examine the expression of a selected panel of genes known to regulate joint development. This work revealed the precise changes to shape, particularly in the distal femur, that occur in an altered mechanical environment, corresponding to predicted changes in the spatial and dynamic patterns of mechanical stimuli and region specific changes in cell proliferation rates. In addition, we show altered patterning of the emerging tissues of the joint interzone with the loss of clearly defined and organised cell territories revealed by loss of characteristic interzone gene expression and abnormal expression of cartilage markers. This work shows that local dynamic patterns of biophysical stimuli generated from muscle contractions in the embryo act as a source of positional information guiding patterning and morphogenesis of the developing knee joint.
Collapse
|
6
|
Nowlan NC, Prendergast PJ, Murphy P. Identification of mechanosensitive genes during embryonic bone formation. PLoS Comput Biol 2008; 4:e1000250. [PMID: 19112485 PMCID: PMC2592698 DOI: 10.1371/journal.pcbi.1000250] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Accepted: 11/11/2008] [Indexed: 11/18/2022] Open
Abstract
Although it is known that mechanical forces are needed for normal bone
development, the current understanding of how biophysical stimuli are
interpreted by and integrated with genetic regulatory mechanisms is limited.
Mechanical forces are thought to be mediated in cells by
“mechanosensitive” genes, but it is a challenge to
demonstrate that the genetic regulation of the biological system is dependant on
particular mechanical forces in vivo. We propose a new means of selecting
candidate mechanosensitive genes by comparing in vivo gene expression patterns
with patterns of biophysical stimuli, computed using finite element analysis. In
this study, finite element analyses of the avian embryonic limb were performed
using anatomically realistic rudiment and muscle morphologies, and patterns of
biophysical stimuli were compared with the expression patterns of four candidate
mechanosensitive genes integral to bone development. The expression patterns of
two genes, Collagen X (ColX) and Indian hedgehog (Ihh), were shown to colocalise
with biophysical stimuli induced by embryonic muscle contractions, identifying
them as potentially being involved in the mechanoregulation of bone formation.
An altered mechanical environment was induced in the embryonic chick, where a
neuromuscular blocking agent was administered in ovo to modify skeletal muscle
contractions. Finite element analyses predicted dramatic changes in levels and
patterns of biophysical stimuli, and a number of immobilised specimens exhibited
differences in ColX and Ihh expression. The results obtained indicate that
computationally derived patterns of biophysical stimuli can be used to inform a
directed search for genes that may play a mechanoregulatory role in particular
in vivo events or processes. Furthermore, the experimental data demonstrate that
ColX and Ihh are involved in mechanoregulatory pathways and may be key mediators
in translating information from the mechanical environment to the molecular
regulation of bone formation in the embryo. While mechanical forces are known to be critical to adult bone maintenance and
repair, the importance of mechanobiology in embryonic bone formation is less
widely accepted. The influence of mechanical forces on cells is thought to be
mediated by “mechanosensitive genes,” genes which respond to
mechanical stimulation. In this research, we examined the situation in the
developing embryo. Using finite element analysis, we simulated the biophysical
stimuli in the developing bone resulting from spontaneous muscle contractions,
incorporating detailed morphology of the developing chick limb. We compared
patterns of stimuli with expression patterns of a number of genes involved in
bone formation and demonstrated a clear colocalisation in the case of two genes
(Ihh and ColX). We then altered the mechanical environment of the growing chick
embryo by blocking muscle contractions and demonstrated changes in the
magnitudes and patterns of biophysical stimuli and in the expression patterns of
both Ihh and ColX. We have demonstrated the value of combining computational
techniques with in vivo gene expression analysis to identify genes that may play
a mechanoregulatory role and have identified genes that respond to mechanical
stimulation during bone formation in vivo.
Collapse
Affiliation(s)
- Niamh C Nowlan
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland.
| | | | | |
Collapse
|
7
|
Abstract
Avian embryos can be completely paralyzed by injection of neuromuscular-blocking agents. We used a single injection of decamethonium iodide to paralyze embryos at 7, 8, or 10 days of incubation and analyzed the growth of individual bones (clavicle, mandible, ulna, femur, tibia, humerus) and of individual muscles that act upon some of those bones (clavicular and sternal heads of m. pectoralis, and mm. biceps brachii, depressor mandibulae, pseudotemporalis, and adductor externus). Growth of the bones is not equally affected by paralysis. Only 27% of clavicular growth (by mass) but 77% of mandibular growth occurred in paralyzed embryos, whereas the four long bones exhibited 52-63% of their normal growth. Analysis of muscle weight, fiber length and physiological cross-sectional area (weight/fiber length) indicate that there was greater reduction of the muscles acting on the limbs than of those acting on the mandible, i.e., diminished growth of the skeleton is correlated with reduced muscular activity. Specific retardation of clavicular growth is due to fusion of sternal rudiments and collapse of the thorax, as well as virtual absence of the musculature that normally attaches to the clavicle. We discuss these results in the light of intrinsic and extrinsic factors governing growth of the embryonic skeleton. Paralysis reduces skeletal growth by reducing both the movements taking place in ovo, and the loads imposed on the bones by muscle contraction, changes that represent alterations in the mechanical environment of the skeleton.
Collapse
Affiliation(s)
- B K Hall
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | | |
Collapse
|
8
|
|
9
|
Khaskiye A, Suignard-Khaskiye G, Renaud D. Acetylcholinesterase in chick embryo latissimus dorsii muscles: effects of curarization and electrical stimulation. Differentiation 1989; 41:110-5. [PMID: 2612761 DOI: 10.1111/j.1432-0436.1989.tb00738.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The accumulation of acetylcholinesterase (AChE), the changes in AChE-specific activity and in AChE molecular form distribution were studied in slow-tonic anterior latissimus dorsi (ALD) and in fast-twitch posterior latissimus dorsi (PLD) muscles of the chick embryo. From stage 36 (day 11) to stage 42 (day 17) of Hamburger and Hamilton, the AChE-specific activity decreased, while the relative proportion of asymmetric A 12 and A 8 forms increased. Repetitive injection of curare resulted at stage 42 (day 17) in a decrease in AChE-specific activity, in the accumulation of the synaptic AChE and in the expression of AChE asymmetric forms. Electrical stimulation at a relatively high frequency (40 Hz) of curarized ALD and PLD muscles resulted in a normal increase in AChE asymmetric forms, whereas a lower frequency (5 Hz) resulted in a dominance of globular forms. Both patterns of stimulation partly prevented the loss in synaptic AChE accumulations. These results suggest that in chick embryo muscles, muscle activity and its rhythms are involved in the normal evolution of AChE.
Collapse
Affiliation(s)
- A Khaskiye
- Centre de Recherche de Biologie et Physico-Chimie Cellulaires, Faculté des Sciences et des Techniques, Nantes, France
| | | | | |
Collapse
|