In this in vivo study, subjects had an increased concentration in circulating glycine, proline, hydroxyproline and hydroxylysine
after one hour of collagen supplementation in contrast to placebo.
Collagen markers deoxypyridinoline and hydroxylysine
glycosides: pediatric reference data and use for growth prediction in growth hormone-deficient children.
Reaction of these carbonyls with the N[H.sub.2] side chain containing amino acids (arginine, lysine, and hydroxylysine
) leads to formation of irreversible AGE compounds such as pentosidine and [N.sup.[epsilon]]-carboxymethyllysine (CML) .
residues are glycosylated and the triple helical structure as noted is formed from two alpha-1 chains and one alpha-2 chain.
 reported that ligament proteins contain high contents of glycine and methionine but are devoid of hydroxyproline and hydroxylysine
. Later, Kikuchi et al.
Vitamin C is the cofactor for enzymes like lysyl hydroxylase and prolyl hydroxylase, enzymes that are very important for making hydroxylysine
and hydroxyproline, which play a crucial role in the stability of the structure of collagen triple helix.
"They contain an unusually high proportion of glycine, proline, hydroxyproline and hydroxylysine
, which are essential elements for production of lean muscles, healthy bones and firm, youthful skin.
it has been shown that electromagnetic stimulation alters the hydroxyproline/ hydroxylysine
of healing tendons.
Urinary excretion of glycosaminoglycans, hydroxyproline and hydroxylysine
in rabbits after excessive ingestion of fluoride.
Effluent-fed mussels were found to have decreased in their proportion of asparagine (ASN), glutamine (GLN), and hydroxylysine
(HLY), whereas their proportion of alanine (ALA) increased throughout the experiment.
They reported increased levels of the collagen degradation products hydroxylysine
and hydroxyproline in a small group of SCI subjects, suggesting decreased skin stiffness and strength.
These enzymes synthesize hydroxylproline and hydroxylysine
, which are components found in collagen23.