scholarly journals Cell accumulation in the junctional region of denervated muscle.

1987 ◽  
Vol 104 (1) ◽  
pp. 109-120 ◽  
Author(s):  
E A Connor ◽  
U J McMahan
Keyword(s):  
Extracellular Matrix ◽  
Interstitial Cell ◽  
Neuromuscular Junctions ◽  
Muscle Fibers ◽  
Interstitial Cells ◽  
Cell Number ◽  
Denervated Muscle ◽  
Direct Role ◽  
Cell Accumulation ◽  
Extracellular Matrix Components

If skeletal muscles are denervated, the number of mononucleated cells in the connective tissue between muscle fibers increases. Since interstitial cells might remodel extracellular matrix, and since extracellular matrix in nerve and muscle plays a direct role in reinnervation of the sites of the original neuromuscular junctions, we sought to determine whether interstitial cell accumulation differs between junctional and extrajunctional regions of denervated muscle. We found in muscles from frog and rat that the increase in interstitial cell number was severalfold (14-fold for frog, sevenfold for rat) greater in the vicinity of junctional sites than in extrajunctional regions. Characteristics of the response at the junctional sites of frog muscles are as follows. During chronic denervation, the accumulation of interstitial cells begins within 1 wk and it is maximal by 3 wk. Reinnervation 1-2 wk after nerve damage prevents the maximal accumulation. Processes of the cells form a multilayered veil around muscle fibers but make little, if any, contact with the muscle cell or its basal lamina sheath. The results of additional experiments indicate that the accumulated cells do not originate from terminal Schwann cells or from muscle satellite cells. Most likely the cells are derived from fibroblasts that normally occupy the space between muscle fibers and are known to make and degrade extracellular matrix components.

Cell-extracellular matrix interactions under in vivo conditions during interstitial cell migration in Hydra vulgaris

Development ◽  
1994 ◽  
Vol 120 (2) ◽  
pp. 425-432 ◽  
Author(s):  
X. Zhang ◽  
M.P. Sarras
Keyword(s):  
Extracellular Matrix ◽  
Cell Migration ◽  
Synthetic Peptide ◽  
Interstitial Cell ◽  
Extracellular Matrix Components ◽  
Matrix Interactions ◽  
Apical Half ◽  
Matrix Components ◽  
Extracellular Matrix Interactions

Interstitial cell (I-cell) migration in hydra is essential for establishment of the regional cell differentiation pattern in the organism. All previous in vivo studies have indicated that cell migration in hydra is a result of cell-cell interactions and chemotaxic gradients. Recently, in vitro cell adhesion studies indicated that isolated nematocytes could bind to substrata coated with isolated hydra mesoglea, fibronectin and type IV collagen. Under these conditions, nematocytes could be observed to migrate on some of these extracellular matrix components. By modifying previously described hydra grafting techniques, two procedures were developed to test specifically the role of extracellular matrix components during in vivo I-cell migration in hydra. In one approach, the extracellular matrix structure of the apical half of the hydra graft was perturbed using beta-aminopropionitrile and beta-xyloside. In the second approach, grafts were treated with fibronectin, RGDS synthetic peptide and antibody to fibronectin after grafting was performed. In both cases, I-cell migration from the basal half to the apical half of the grafts was quantitatively analyzed. Statistical analysis indicated that beta-aminopropionitrile, fibronectin, RGDS synthetic peptide and antibody to fibronectin all were inhibitory to I-cell migration as compared to their respective controls. beta-xyloside treatment had no effect on interstitial cell migration. These results indicate the potential importance of cell-extracellular matrix interactions during in vivo I-cell migration in hydra.

scholarly journals Agrin-induced reorganization of extracellular matrix components on cultured myotubes: relationship to AChR aggregation.

1990 ◽  
Vol 111 (3) ◽  
pp. 1161-1170 ◽  
Author(s):  
R M Nitkin ◽  
T C Rothschild
Keyword(s):  
Extracellular Matrix ◽  
Type Iv Collagen ◽  
Neuromuscular Junctions ◽  
Synaptic Organization ◽  
Type Iv ◽  
Extracellular Matrix Components ◽  
Cultured Myotubes ◽  
Matrix Components ◽  
Induced Aggregation

Agrin, an extracellular matrix-associated protein extracted from synapse-rich tissues, induces the accumulation of acetylcholine receptors (AChRs) and other synaptic components into discrete patches on cultured myotubes. The appearance of agrin-like molecules at neuromuscular junctions suggests that it may direct synaptic organization in vivo. In the present study we examined the role of extracellular matrix components in agrin-induced differentiation. We used immunohistochemical techniques to visualize the spatial and temporal distribution of laminin, a heparan sulfate proteoglycan (HSPG), fibronectin, and type IV collagen on cultured chick myotubes during agrin-induced aggregation of AChRs. Myotubes displayed significant amounts of laminin and HSPG, lesser amounts of type IV collagen, and little, if any, fibronectin. Agrin treatment caused cell surface laminin and HSPG to patch, while collagen and fibronectin distributions were generally unaffected. Many of the agrin-induced laminin and HSPG patches colocalized with AChR patches, raising the possibility of a causal relationship between matrix patching and AChR accumulations. However, patching of AChRs (complete within a few hours) preceded that of laminin or HSPG (not complete until 15-20 h), making it unlikely that matrix accumulations initiate AChR patching at agrin-induced sites. Conversely, when AChR patching was blocked by treatment with anti-AChR antibody mAb 35, agrin was still able to effect patching of laminin and HSPG. Taken together, these findings suggest that agrin-induced accumulations of AChR and laminin/HSPG are not mechanistically linked.

scholarly journals Extracellular Matrix Components as Diagnostic Tools in Inflammatory Bowel Disease

Biology ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1024
Author(s):  
Laura Golusda ◽  
Anja A. Kühl ◽  
Britta Siegmund ◽  
Daniela Paclik
Keyword(s):  
Inflammatory Bowel Disease ◽  
Extracellular Matrix ◽  
Bowel Disease ◽  
Diagnostic Methods ◽  
Regulatory Function ◽  
Diagnostic Tools ◽  
Disease Course ◽  
Direct Role ◽  
Extracellular Matrix Components ◽  
Inflammatory Bowel

Work from the last years indicates that the extracellular matrix (ECM) plays a direct role in various cellular processes, including proliferation, migration and differentiation. Besides homeostatic processes, its regulatory function in inflammation becomes more and more evident. In inflammation, such as inflammatory bowel disease, the ECM composition is constantly remodeled, and this can result in a structuring of fistulizing disease course. Thus, tracking early ECM changes might bear the potential to predict the disease course. In this review, we provide an overview of relevant diagnostic methods, focusing on ECM changes.

Interstitial Cells in the Regeneration of Cordylophora lacustris

1952 ◽  
Vol s3-93 (23) ◽  
pp. 269-288
Author(s):  
JANET MOORE
Keyword(s):  
Histological Examination ◽  
Ribonucleic Acid ◽  
Interstitial Cell ◽  
Interstitial Cells ◽  
Oral Cone ◽  
Cell Accumulation

1. Histological examination of developing reconstitution masses of Cordylophora lacustris has shown that interstitial cells accumulate in the tips of developing outgrowths, and that in contrast to other regions these interstitial cells are situated in the endoderm. 2. These interstitial cells do not differentiate into the ectoderm and endoderm of the regenerant, but persist and increase in the adult oral cone. 3. Interstitial cells do not accumulate in regions of growth (stolon tips) or growth and differentiation (induced outgrowths) that do not contain the rudiment of an oral cone. 4. An invariable association has been established between the presence of an interstitial cell accumulation in the endoderm and hydranth-inducing power of tissue when grafted to a mass. Outgrowth tips and oral cones both have inducing power and interstitial cell accumulations; basal hydranth regions and tentacles have inducing power, and although there is no interstitial cell accumulation in these regions of the intact hydranth, it appears before a graft produces induction. 5. There is evidence that interstitial cells are particularly rich in ribonucleic acid. Whether this property is directly related to the function of induction has yet to be determined.

scholarly journals Effects of Purified Recombinant Neural and Muscle Agrin on Skeletal Muscle Fibers in Vivo

2001 ◽  
Vol 153 (7) ◽  
pp. 1441-1452 ◽  
Author(s):  
Gabriela Bezakova ◽  
Johannes P. Helm ◽  
Maura Francolini ◽  
Terje Lømo
Keyword(s):  
Acetylcholine Receptors ◽  
Neuromuscular Junctions ◽  
Muscle Fibers ◽  
Transgenic Animals ◽  
Denervated Muscle ◽  
Rat Soleus Muscle ◽  
The Stability ◽  
Dose Dependent ◽  
Electrical Muscle

Aggregation of acetylcholine receptors (AChRs) in muscle fibers by nerve-derived agrin plays a key role in the formation of neuromuscular junctions. So far, the effects of agrin on muscle fibers have been studied in culture systems, transgenic animals, and in animals injected with agrin–cDNA constructs. We have applied purified recombinant chick neural and muscle agrin to rat soleus muscle in vivo and obtained the following results. Both neural and muscle agrin bind uniformly to the surface of innervated and denervated muscle fibers along their entire length. Neural agrin causes a dose-dependent appearance of AChR aggregates, which persist ≥7 wk after a single application. Muscle agrin does not cluster AChRs and at 10 times the concentration of neural agrin does not reduce binding or AChR-aggregating activity of neural agrin. Electrical muscle activity affects the stability of agrin binding and the number, size, and spatial distribution of the neural agrin–induced AChR aggregates. Injected agrin is recovered from the muscles together with laminin and both proteins coimmunoprecipitate, indicating that agrin binds to laminin in vivo. Thus, the present approach provides a novel, simple, and efficient method for studying the effects of agrin on muscle under controlled conditions in vivo.

scholarly journals Chick myotendinous antigen. II. A novel extracellular glycoprotein complex consisting of large disulfide-linked subunits.

1984 ◽  
Vol 98 (6) ◽  
pp. 1937-1946 ◽  
Author(s):  
M Chiquet ◽  
D M Fambrough
Keyword(s):  
Extracellular Matrix ◽  
Biochemical Characterization ◽  
Muscle Fibers ◽  
Soluble Form ◽  
Secretory Proteins ◽  
Glycoprotein Complex ◽  
Limb Morphogenesis ◽  
Extracellular Matrix Components ◽  
Muscle Cultures

This report describes the biochemical characterization of a novel extracellular matrix component, " myotendinous antigen," which appears early in chick limb morphogenesis at sites connecting developing muscle fibers, tendons, and bone ( Chiquet , M., and D. Fambrough , 1984; J. Cell Biol., 98:1926-1936). This extracellular matrix antigen is a major component of the secretory proteins released into the medium by fibroblast and muscle cultures; the soluble form is characterized here. This form of myotendinous antigen is a large glycoprotein complex consisting of several disulfide linked subunits (Mr approximately 150,000-240,000). The differently sized antigen subunits are related, since they yielded very similar proteolytic cleavage patterns. M1 antibody can bind to the denatured subunits. The antigen subunits, as well as a Mr approximately 80,000 pepsin-resistant antigenic domain derived from them, are resistant to bacterial collagenase. Despite possessing subunits similar in size to fibronectin, myotendinous antigen appears to be both structurally and antigenically unrelated to fibronectin or to other known extracellular matrix components. About seven times more M1 antigen per cell nucleus was released into the medium in fibroblast as compared to muscle cultures. In muscle conditioned medium, myotendinous antigen is noncovalently complexed to very high molecular weight material that could be heavily labeled by [3H]glucosamine and [35S]sulfate. This material is sensitive to chondroitinase ABC and hence appears to contain sulfated glycosaminoglycans. We speculate that myotendinous antigen might interact with proteoglycans on the surface of muscle fibers, thereby acting as a link to tendons.

scholarly journals Extracellular Matrix Components as Diagnostic Tools in Inflammatory Bowel Disease

2021 ◽  
Author(s):  
Laura Golusda ◽  
Anja A Kühl ◽  
Britta Siegmund ◽  
Daniela Paclik
Keyword(s):  
Inflammatory Bowel Disease ◽  
Extracellular Matrix ◽  
Bowel Disease ◽  
Diagnostic Methods ◽  
Regulatory Function ◽  
Diagnostic Tools ◽  
Disease Course ◽  
Direct Role ◽  
Extracellular Matrix Components ◽  
Inflammatory Bowel

Work from the last years indicate that the extracellular matrix (ECM) plays a direct role in vari-ous cellular processes including proliferation, migration and differentiation. Besides homeostat-ic processes, its regulatory function in inflammation becomes more and more evident. In in-flammation like inflammatory bowel disease, the ECM composition is constantly remodeled which can result in a structuring of fistulizing disease course. Thus, tracking early ECM changes might bear the potential to predict the disease course. In this review, we will provide an over-view of relevant diagnostic methods focusing on ECM changes.

scholarly journals Syndecan-4-/- mice have smaller muscle fibers, increased Akt/mTOR/S6K1 and Notch/HES-1 pathways, and alterations in extracellular matrix components

2020 ◽  
Author(s):  
Sissel Beate Rønning ◽  
Cathrine Rein Carlson ◽  
Jan Magnus Aronsen ◽  
Addolorata Pisconti ◽  
Vibeke Høst ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Protein Level ◽  
Cell Activation ◽  
Molecular Mechanisms ◽  
Muscle Development ◽  
Muscle Fibers ◽  
Mrna Levels ◽  
Ecm Remodeling ◽  
Genetic Ablation ◽  
Extracellular Matrix Components

AbstractBackgroundExtracellular matrix (ECM) remodeling is essential for skeletal muscle development and adaption in response to environmental cues such as exercise and injury. The cell surface proteoglycan syndecan-4 has been reported to be essential for muscle differentiation, but few molecular mechanisms are known. Syndecan-4-/- mice are unable to regenerate damaged muscle, and display deficient satellite cell activation, proliferation, and differentiation. A reduced myofiber basal lamina has also been reported in syndecan-4-/- muscle, indicating possible defects in ECM production. To get a better understanding of the underlying molecular mechanisms, we have here investigated the effects of syndecan-4 genetic ablation on molecules involved in ECM remodeling and muscle growth, both under steady state conditions and in response to exercise.MethodsTibialis anterior (TA) muscles from sedentary and exercised syndecan-4-/- and WT mice were analyzed by immunohistochemistry, real-time PCR and western blotting.ResultsCompared to WT, we found that syndecan-4-/- mice had reduced body weight, reduced muscle weight, muscle fibers with a smaller cross-sectional area, and reduced expression of myogenic regulatory transcription factors. Sedentary syndecan-4-/- had also increased mRNA levels of syndecan-2, decorin, collagens, fibromodulin, biglycan, and LOX. Some of these latter ECM components were reduced at protein level, suggesting them to be more susceptible to degradation or less efficiently translated when syndecan-4 is absent. At the protein level, TRPC7 was reduced, whereas activation of the Akt/mTOR/S6K1 and Notch/HES-1 pathways were increased. Finally, although exercise induced upregulation of several of these components in WT, a further upregulation of these molecules was not observed in exercised syndecan-4-/- mice.ConclusionsAltogether our data suggest an important role of syndecan-4 in muscle development.

scholarly journals Chick myotendinous antigen. I. A monoclonal antibody as a marker for tendon and muscle morphogenesis.

1984 ◽  
Vol 98 (6) ◽  
pp. 1926-1936 ◽  
Author(s):  
M Chiquet ◽  
D M Fambrough
Keyword(s):  
Extracellular Matrix ◽  
Biochemical Characterization ◽  
Muscle Fibers ◽  
Antigenic Site ◽  
Chick Embryos ◽  
Adult Skeletal Muscle ◽  
Limb Morphogenesis ◽  
Extracellular Matrix Components ◽  
Nonmuscle Cells ◽  
Anterior Latissimus Dorsi

Extracellular matrix components are likely to be involved in the interaction of muscle with nonmuscle cells during morphogenesis and in adult skeletal muscle. With the aim of identifying relevant molecules, we generated monoclonal antibodies that react with the endomysium, i.e., the extracellular matrix on the surface of single muscle fibers. Antibody M1, which is described here, specifically labeled the endomysium of chick anterior latissimus dorsi muscle (but neither the perimysium nor, with the exception of blood vessels and perineurium, the epimysium ). Endomysium labeling was restricted to proximal and distal portions of muscle fibers near their insertion points to tendon, but absent from medial regions of the muscle. Myotendinous junctions and tendon fascicles were intensely labeled by M1 antibody. In chick embryos, " myotendinous antigen" (as we tentatively call the epitope recognized by M1 antibody) appeared first in the perichondrium of vertebrae and limb cartilage elements, from where it gradually extended to the premuscle masses. Around day 6, tendon primordia were clearly labeled. The other structures labeled by M1 antibody in chick embryos were developing smooth muscle tissues, especially aorta, gizzard, and lung buds. In general, tissues labeled with M1 antibody appeared to be a subset of the ones accumulating fibronectin. In cell cultures, M1 antibody binds to fuzzy, fibrillar material on the substrate and cell surfaces of living fibroblast and myogenic cells, which confirms an extracellular location of the antigenic site. The appearance of myotendinous antigen during limb morphogenesis and its distribution in adult muscle and tendon are compatible with the idea that it might be involved in attaching muscle fibers to tendon fascicles. Its biochemical characterization is described in the accompanying paper ( Chiquet , M., and D. Fambrough , 1984, J. Cell Biol. 98:1937-1946).

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