scholarly journals Proteoglycan-collagen arrangements in developing rat tail tendon. An electron microscopical and biochemical investigation

1981 ◽  
Vol 195 (3) ◽  
pp. 573-581 ◽  
Author(s):  
J E Scott ◽  
C R Orford ◽  
E W Hughes
Keyword(s):  
Rapid Growth ◽  
Collagen Fibril ◽  
Chondroitin Sulphate ◽  
Post Partum ◽  
Dermatan Sulphate ◽  
Concentration Method ◽  
Sigmoid Curve ◽  
Tail Tendon ◽  
Electron Microscopical ◽  
Fibril Diameter

1. Developing tail tendons from rats (19-day foetal to 126 days post partum) were examined by electron microscopy after staining for proteoglycan with a cationic copper phthalocyanin dye. Cuprolinic Blue, in a “critical electrolyte concentration” method. Hydroxyproline was measured on papain digests of tendons, from which glycosaminoglycuronans were isolated, characterized and quantified. 2. Mean collagen fibril diameters increased more than 10-fold with age according to a sigmoid curve, the rapid growth phase 2 being during 30-90 days after conception. Fibril periodicities were considerably smaller (50-55 nm) in phases 1 and 2 than in phase 3 (greater than 62 nm). 3. Dermatan sulphate is the main glycosaminoglycuronan in mature tendon. Chondroitin sulphate and hyaluronate preponderate in foetal tissue. 4. Proteoglycan was seen around but not inside collagen fibrils. Proteoglycan and collagen were quantified from electron micrographs. Their ratios behaved similarly to uronic acid/hydroxyproline and hyaluronate/hydroxyproline ratios, which decreased rapidly around birth, and then levelled off to a low plateau coincident with the onset of rapid growth in collagen fibril diameter. 5. Dermatan sulphate/hydroxyproline ratios suggest that the proteoglycan orthogonal array around the fibril is largely dermatan sulphate. In the foetus hyaluronate and chondroitin sulphate exceed that expected to be bound to collagen. 6. An inhibiting action of chondroitin sulphate-rich proteoglycan on fibril diameter growth is suggested. 7. The distributions of hyaluronate, chondroitin sulphate and dermatan sulphate are discussed in the light of secondary structures suggested to be present in hyaluronate and chondroitin sulphate, but not in dermatan sulphate.

scholarly journals Bimodal collagen fibril diameter distributions direct age-related variations in tendon resilience and resistance to rupture

2012 ◽  
Vol 113 (6) ◽  
pp. 878-888 ◽  
Author(s):  
K. L. Goh ◽  
D. F. Holmes ◽  
Y. Lu ◽  
P. P. Purslow ◽  
K. E. Kadler ◽  
...  
Keyword(s):  
Collagen Fibril ◽  
Strain Energy ◽  
Age Groups ◽  
Bimodal Distribution ◽  
Tensile Tests ◽  
Age Related ◽  
Transmission Electron ◽  
Rupture Energy ◽  
Tail Tendon ◽  
Fibril Diameter

Scaling relationships have been formulated to investigate the influence of collagen fibril diameter ( D) on age-related variations in the strain energy density of tendon. Transmission electron microscopy was used to quantify D in tail tendon from 1.7- to 35.3-mo-old (C57BL/6) male mice. Frequency histograms of D for all age groups were modeled as two normally distributed subpopulations with smaller ( DD1) and larger ( DD2) mean Ds, respectively. Both DD1 and DD2 increase from 1.6 to 4.0 mo but decrease thereafter. From tensile tests to rupture, two strain energy densities were calculated: 1) uE [from initial loading until the yield stress (σ Y)], which contributes primarily to tendon resilience, and 2) uF [from σ Y through the maximum stress (σ U) until rupture], which relates primarily to resistance of the tendons to rupture. As measured by the normalized strain energy densities uE/σ Y and uF/σ U, both the resilience and resistance to rupture increase with increasing age and peak at 23.0 and 4.0 mo, respectively, before decreasing thereafter. Multiple regression analysis reveals that increases in uE/σ Y (resilience energy) are associated with decreases in DD1 and increases in DD2, whereas uF/σ U (rupture energy) is associated with increases in DD1 alone. These findings support a model where age-related variations in tendon resilience and resistance to rupture can be directed by subtle changes in the bimodal distribution of Ds.

scholarly journals Dermatan sulphate-rich proteoglycan associates with rat tail-tendon collagen at the d band in the gap region

1981 ◽  
Vol 197 (1) ◽  
pp. 213-216 ◽  
Author(s):  
J E Scott ◽  
C R Orford
Keyword(s):  
Phosphotungstic Acid ◽  
Electrolyte Concentration ◽  
Proteinase Inhibitors ◽  
Uranyl Acetate ◽  
Dermatan Sulphate ◽  
Concentration Method ◽  
Collagen Molecules ◽  
Tail Tendon ◽  
Rat Tail ◽  
Tendon Collagen

Rat tail tendon was stained with a cationic phthalocyanin dye, Cupromeronic Blue, in a ‘critical-electrolyte-concentration’ method [Scott (1980) Biochem. J. 187, 887-891] specifically to demonstrate proteoglycan by electron microscopy. Hyaluronidase digestion in the presence of proteinase inhibitors corroborated the results. Collagen was stained with uranyl acetate and/or phosphotungstic acid to demonstrate the banding pattern a-e in the D period. Proteoglycan was distributed about the collagen fibrils in an orthogonal array, the transverse elements of which were located almost exclusively at the d band, in the gap zone. The proteoglycan may inhibit (1) fibril radial growth by accretion of collagen molecules or fibril fusion, through interference with cross-linking, and (2) calcification by occupying the holes in the gap region later to be filled with hydroxyapatite.

scholarly journals Pilot study on the effects of preservatives on corneal collagen parameters measured by small angle X-ray scattering analysis

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Susyn Joan Kelly ◽  
Lizette duPlessis ◽  
John Soley ◽  
Frazer Noble ◽  
Hannah Carolyn Wells ◽  
...  
Keyword(s):  
Small Angle ◽  
Collagen Fibril ◽  
Diameter Distribution ◽  
X Ray ◽  
X Ray Scattering ◽  
Saxs Analysis ◽  
Triton X ◽  
Fibril Diameter ◽  
Corneal Collagen ◽  
Ray Scattering

Abstract Objective Small angle X-ray scattering (SAXS) analysis is a sensitive way of determining the ultrastructure of collagen in tissues. Little is known about how parameters measured by SAXS are affected by preservatives commonly used to prevent autolysis. We determined the effects of formalin, glutaraldehyde, Triton X and saline on measurements of fibril diameter, fibril diameter distribution, and D-spacing of corneal collagen using SAXS analysis. Results Compared to sections of sheep and cats’ corneas stored frozen as controls, those preserved in 5% glutaraldehyde and 10% formalin had significantly larger mean collagen fibril diameters, increased fibril diameter distribution and decreased D-spacing. Sections of corneas preserved in Triton X had significantly increased collagen fibril diameters and decreased fibril diameter distribution. Those preserved in 0.9% saline had significantly increased mean collagen fibril diameters and decreased diameter distributions. Subjectively, the corneas preserved in 5% glutaraldehyde and 10% formalin maintained their transparency but those in Triton X and 0.9% saline became opaque. Subjective morphological assessment of transmission electron microscope images of corneas supported the SAXS data. Workers using SAXS analysis to characterize collagen should be alerted to changes that can be introduced by common preservatives in which their samples may have been stored.

Ageing Changes in the Tensile Properties of Tendons: Influence of Collagen Fibril Volume Fraction

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
K. L. Goh ◽  
D. F. Holmes ◽  
H.-Y. Lu ◽  
S. Richardson ◽  
K. E. Kadler ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Collagen Fibril ◽  
Volume Fraction ◽  
Area Fraction ◽  
Sectional Area ◽  
Cross Sectional ◽  
P Values ◽  
Age Related ◽  
Fibril Diameter ◽  
Age Related Changes

Connective tissues are biological composites comprising of collagen fibrils embedded in (and reinforcing) the hydrated proteoglycan-rich (PG) gel within the extracellular matrices (ECMs). Age-related changes to the mechanical properties of tissues are often associated with changes to the structure of the ECM, namely, fibril diameter. However, quantitative attempts to correlate fibril diameter to mechanical properties have yielded inconclusive evidence. Here, we described a novel approach that was based on the rule of mixtures for fiber composites to evaluate the dependence of age-related changes in tendon tensile strength (σ) and stiffness (E) on the collagen fibril cross-sectional area fraction (ρ), which is related to the fibril volume fraction. Tail tendons from C57BL6 mice from age groups 1.6–35.3months old were stretched to failure to determine σ and E. Parallel measurements of ρ as a function of age were made using transmission electron microscopy. Mathematical models (rule of mixtures) of fibrils reinforcing a PG gel in tendons were used to investigate the influence of ρ on ageing changes in σ and E. The magnitudes of σ, E, and ρ increased rapidly from 1.6monthsto4.0months (P-values <0.05) before reaching a constant (age independent) from 4.0monthsto29.0months (P-values >0.05); this trend continued for E and ρ (P-values >0.05) from 29.0monthsto35.3months, but not for σ, which decreased gradually (P-values <0.05). Linear regression analysis revealed that age-related changes in σ and E correlated positively to ρ (P-values <0.05). Collagen fibril cross-sectional area fraction ρ is a significant predictor of ageing changes in σ and E in the tail tendons of C57BL6 mice.

Growth and development of collagen fibrils in immature tissues from rat and sheep

1981 ◽  
Vol 212 (1186) ◽  
pp. 85-92 ◽  
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Collagen Fibril ◽  
Growth And Development ◽  
Collagen Fibrils ◽  
Diameter Distribution ◽  
Rat Tissues ◽  
Transmission Electron ◽  
The Mean ◽  
Fibril Diameter

The collagen fibril diameter distribution of four immature tissues from both rat and sheep have been determined from transverse sections observed in the transmission electron microscope. In many instances before birth, the form of the distribution for the tissues is both unimodal and sharp and the mean diameters of the distributions lie close to a multiple of 80 Å. For some tissues, the collagen fibril diameter distributions may be resolved into a number of components, each of which represents a population of fibrils with a diameter close to a multiple of 80 Å (8 nm). These data confirm and extend previous observations by the authors that small collagen fibrils all have diameters that are multiples of about 80 Å and that the fibril growth occurs by the accretion of 80 Å units. The form of the collagen fibril diameter distribution at birth is broad for the sheep tissues but narrow for the rat tissues, thus confirming that the range of fibril diameters at this stage of life reflects the differing degree of development of precocious and altricious animals.

scholarly journals Attempted isolation of a heparin proteoglycan from bovine liver capsule

1970 ◽  
Vol 116 (1) ◽  
pp. 27-34 ◽  
Author(s):  
U. Lindahl
Keyword(s):  
Potassium Chloride ◽  
Chondroitin Sulphate ◽  
Cetylpyridinium Chloride ◽  
Bovine Liver ◽  
Gel Chromatography ◽  
Dermatan Sulphate ◽  
Liver Capsule ◽  
Neutral Sugars ◽  
Degraded Material ◽  
Heparin Preparation

(1) Polysaccharides were isolated from bovine liver capsule by extraction with 2m-potassium chloride followed by precipitation from 0.8m-potassium chloride with cetylpyridinium chloride. Chondroitin sulphate was eliminated by digestion with hyaluronidase. The yield of heparin was approx. 40% of that obtained after extraction of the papain-digested tissue. (2) The macromolecular properties of the hyaluronidase-digested polysaccharide were studied by gel chromatography on Sephadex G-200 of the intact, as well as of the alkali-degraded, material. The results suggested the presence of single heparin chains in addition to a dermatan sulphate proteoglycan. (3) A purified heparin preparation was analysed for amino acids and neutral sugars. Xylose, galactose and serine were found in amounts corresponding to 0.1, 0.2, and 0.4 residue/polysaccharide chain (mol.wt. 7400), respectively. It is suggested that the isolated material had been degraded by a polysaccharidase with endo-enzyme properties.

Stress Dependent Collagen Fibril Diameter Distribution in Human Aortic Valves

2007 ◽  
Author(s):  
Angelique Balguid ◽  
Anita Mol ◽  
Niels Driessen ◽  
Carlijn Bouten ◽  
Frank Baaijens
Keyword(s):  
Mechanical Properties ◽  
Collagen Fibril ◽  
Diameter Distribution ◽  
Connective Tissues ◽  
Aortic Valves ◽  
Cross Links ◽  
Fibril Morphology ◽  
Stress Dependent ◽  
Collagenous Tissues ◽  
Fibril Diameter

The mechanical properties of collagenous tissues are known to depend on a wide variety of factors, such as the type of tissue and the composition of its extracellular matrix. Relating mechanical roles to individual matrix components in such a complex system is difficult, if not impossible. However, as collagen is the main load bearing component in connective tissues, the relation between collagen and tissue biomechanics has been studied extensively in various types of tissues. The type of collagen, the amount and type of inter- and intramolecular covalent cross-links and collagen fibril morphology are involved in the tissues mechanical behavior (Beekman et al., 1997; Parry et al., 1978; Avery and Bailey, 2005). From literature it is known that the the collagen fibril diameter distribution can be directly related to the mechanical properties of the tissue. In particular, the diameter distribution of collagen fibrils is largely determined by the tissues requirement for tensile strength and elasticity (Parry et al., 1978).

A Morphometric analysis of osteoid collagen fibril diameter in osteogenesis imperfecta

Bone ◽  
1994 ◽  
Vol 15 (3) ◽  
pp. 329-334 ◽  
Author(s):  
J.P. Cassella ◽  
P. Barber ◽  
A.C. Catterall ◽  
S.Yousuf Ali
Keyword(s):  
Osteogenesis Imperfecta ◽  
Morphometric Analysis ◽  
Collagen Fibril ◽  
Fibril Diameter

Dermatan sulphate promotes neuronal differentiation in mouse and human stem cells

2020 ◽  
Author(s):  
Chika Ogura ◽  
Kazumi Hirano ◽  
Shuji Mizumoto ◽  
Shuhei Yamada ◽  
Shoko Nishihara
Keyword(s):  
Stem Cells ◽  
Neurite Outgrowth ◽  
Neuronal Differentiation ◽  
Neural Progenitor Cells ◽  
Chondroitin Sulphate ◽  
Heparan Sulphate ◽  
Embryonic Stem ◽  
Hydroxyl Group ◽  
Human Stem Cells ◽  
Dermatan Sulphate

Abstract Dermatan sulphate (DS), a glycosaminoglycan, is present in the extracellular matrix and on the cell surface. Previously, we showed that heparan sulphate plays a key role in the maintenance of the undifferentiated state in mouse embryonic stem cells (mESCs) and in the regulation of their differentiation. Chondroitin sulphate has also been to be important for pluripotency and differentiation of mESCs. Keratan sulphate is a marker of human pluripotent stem cells. To date, however, the function of DS in mESCs has not been clarified. Dermatan 4 sulfotransferase 1, which transfers sulphate to the C-4 hydroxyl group of N-acetylgalactosamine of DS, contributes to neuronal differentiation of mouse neural progenitor cells. Therefore, we anticipated that neuronal differentiation would be induced in mESCs in culture by the addition of DS. To test this expectation, we investigated neuronal differentiation in mESCs and human neural stem cells (hNSCs) cultures containing DS. In mESCs, DS promoted neuronal differentiation by activation of extracellular signal-regulated kinase 1/2 and also accelerated neurite outgrowth. In hNSCs, DS promoted neuronal differentiation and neuronal migration, but not neurite outgrowth. Thus, DS promotes neuronal differentiation in both mouse and human stem cells, suggesting that it offers a novel method for efficiently inducing neuronal differentiation.

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