Collagen crosslinks and their relationship to the thermal properties of calf tendons

Horgan, Douglas J.; King, N.; Kurth, Lyndon B.; Kuypers, Ronald

doi:10.1016/0003-9861(90)90407-p

Cited by 67 publications

(21 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thermal denaturation of collagen includes an initial melting of less cross-linked triple-helical monomers at lower temperature, followed by denaturation of cross-linked collagen molecules, whereas any inherently denatured collagen cannot refold at physiological temperatures and so does not contribute to a thermogram (32,34). In addition, the denaturation peak pattern of a DSC thermogram correlates with the degree of intermolecular cross-linking (35), supported by the similar melting points and enthalpies of the pepsin-treated (i.e. non-cross-linked) collagens.…”

Section: Discussionmentioning

confidence: 99%

Increased C-telopeptide Cross-linking of Tendon Type I Collagen in Fibromodulin-deficient Mice

Kalamajski¹,

Liu

Tillgren³

et al. 2014

Journal of Biological Chemistry

View full text Add to dashboard Cite

Background:Collagen cross-linking mechanisms must be regulated to obtain tissue-specific collagen fiber properties. Results: Deficiency in collagen-associated protein fibromodulin leads to excessively cross-linked specific domain of collagen. Conclusion: Fibromodulin modulates site-specific cross-linking of collagen. Significance: This is the first report showing that a collagen-associated protein can modulate cross-linking of specific collagen domains.

show abstract

Section: Discussionmentioning

confidence: 99%

Increased C-telopeptide Cross-linking of Tendon Type I Collagen in Fibromodulin-deficient Mice

Kalamajski¹,

Liu

Tillgren³

et al. 2014

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…46 The measured denaturation temperature and degree and type of crosslinking are also typical for maturing tendon. 24 Crosslinking was dominated by HLNL, as measured by ion-exchange chromatography, and further supported by the BTT behavior during HIT testing. Immature collagens have been reported with 1 mole or more of total intermediate crosslinks per mole of collagen.…”

Section: Bovine Tail Tendon Modelmentioning

confidence: 99%

Increased Proteolysis of Collagen in an In Vitro Tensile Overload Tendon Model

et al. 2007

View full text Add to dashboard Cite

Presently, there is a lack of fundamental understanding regarding changes in collagen's molecular state due to mechanical damage. The bovine tail tendon (BTT; steers approximately 30 months) was characterized and used as an in vitro model for investigating the effect of tensile mechanical overload on collagen susceptibility to proteolysis by acetyltrypsin and alpha-chymotrypsin. Two strain rates with a 1000-fold difference (0.01 and 10 s(-1)) were used, since molecular mechanisms that determine mechanical behavior were presumed to be strain rate dependent. First, it was determined that the BTTs were normal but immature tendons. Water content and collagen content (approx. 60% of wet weight and 80% of dry weight, respectively) and mechanical properties were all within the expected range. The collagen crosslinking was dominated by the intermediate crosslink hydroxylysinonorleucine. Second, tensile overload damage significantly enhanced proteolysis by acetyltrypsin and, to a lesser degree, by alpha-chymotrypsin. Interestingly, proteolysis by acetyltrypsin was greatest for specimens ruptured at 0.01 s(-1) and seemed to occur throughout the specimen. Understanding damage is important for insight into injuries (as in sports and trauma) and for better understanding of collagen fiber stability, durability, and damage mechanisms, aiding in the development of durable tissue-based products for mechanically demanding surgical applications.

show abstract

“…These experiments supported previous preliminary indications that the pyrroles were concentrated at the N-telopeptide site. Estimation of the pyrrole has been made using the color yield of digests with Ehrlich's reagent and correlated to the strength of tendon (12). The content of pyrrole decreases with age in mature animals (13,14) and is also lowered in mineralizing tissue (15) and the osteoporotic femoral head compared with normal (16).…”

mentioning

confidence: 99%

Structural Characterization of Pyrrolic Cross-links in Collagen Using a Biotinylated Ehrlich's Reagent

Brady¹,

Robins²

2001

Journal of Biological Chemistry

View full text Add to dashboard Cite

The structures of pyrrolic forms of cross-links in collagen have been confirmed by reacting collagen peptides with a biotinylated Ehrlich's reagent. This reagent was synthesized by converting the cyano group of N-methyl-N-cyanoethyl-4-aminobenzaldehyde to a carboxylic acid, followed by conjugation with biotin pentylamine. Derivatization of peptides from bone collagen both stabilized the pyrroles and facilitated selective isolation of the pyrrole-containing peptides using a monomeric avidin column. Reactivity of the biotinylated reagent with collagen peptides was similar to that of the standard Ehrlich reagent, but heat denaturation of the tissue before enzyme digestion resulted in the loss of about 50% of the pyrrole cross-links. Identification of a series of peptides by mass spectrometry confirmed the presence of derivatized pyrrole structures combined with between 1 and 16 amino acid residues. Almost all of the pyrrole-containing peptides appeared to be derived from N-terminal telopeptide sequences, and the nonhydroxylated (lysine-derived) form predominated over pyrrole cross-links derived from helical hydroxylysine.The chemistry of the lysine-derived collagen cross-links is relatively complex, with collagen type, tissue location, and age of the protein all influencing the range of cross-links present (1). In bone, cartilage, and tendon, extensive hydroxylation of telopeptide lysine residues leads to the formation of hydroxylysyl aldehydes. These aldehydes interact with the ⑀ amino group of lysine or hydroxylysine residues from the adjacent helix to initially form Schiff bases that can chemically rearrange to form a more stable, keto-imine difunctional cross-link. In skin, the telopeptides are not hydroxylated, and no such rearrangement of the Schiff base cross-link occurs. These two different chemistries, dependent on telopeptide lysine hydroxylation, lead to the formation of different mature cross-links by further reaction of the difunctional cross-links in a tissuespecific manner: hydroxylation of the telopeptide lysine residues appears to be accomplished by tissue-specific enzymes, distinct from those that hydroxylate lysines in the helix (2). For the hydroxylysyl aldehyde pathway (bone, cartilage, and tendon), the difunctional cross-links can combine with another hydroxylysine aldehyde-derived component to form a pyridinium cross-link. These cross-links have been extensively characterized, and mechanisms of formation have been proposed (3, 4). However, many studies of cross-linked collagen peptides have implied the presence of other trifunctional cross-links because of a lack of stoichiometric amounts of the pyridinium compounds (5, 6). The possible presence of pyrrolic components in collagen arose from the observation that reaction of bone with p-dimethylaminobenzaldehyde gave a pink color characteristic of pyrroles (7); these reactive species were named Ehrlich chromogens. Later experiments used diazo-affinity columns (also consistent with a pyrrolic structure) to covalently bind the Ehrlich chromogen-c...

show abstract

Collagen crosslinks and their relationship to the thermal properties of calf tendons

Cited by 67 publications

References 15 publications

Increased C-telopeptide Cross-linking of Tendon Type I Collagen in Fibromodulin-deficient Mice

Increased C-telopeptide Cross-linking of Tendon Type I Collagen in Fibromodulin-deficient Mice

Increased Proteolysis of Collagen in an In Vitro Tensile Overload Tendon Model

Structural Characterization of Pyrrolic Cross-links in Collagen Using a Biotinylated Ehrlich's Reagent

Contact Info

Product

Resources

About