(OHP) in urine have been suggested as disease biomarkers for bone turnover and osteoporosis .
A simple method to determine nanogram levels of 4-hydroxyproline
in biological tissues.
SD principally resulted in the decrease of metabolites of glycolysis, pentose phosphate pathway (PPP), branched chain amino acids (BCAA, including valine, leucine, and isoleucine), tyrosine, and the amino acids related to potential antioxidation (cysteine, threonine, serine, methionine, and 4-hydroxyproline
) and the increase of fat metabolism derivatives (glycerol 3-phosphate and 3-hydroxybutyric acid) and neurotransmitter (glutamic acid and aspartic acid) in the brain.
Hee, "A simple method to determine nanogram levels of 4-hydroxyproline
in biological tissues," Analytical Biochemistry, vol.
was strongly decreased in liver, muscle, and plasma.
Determination of 4-hydroxyproline
was performed according to the procedure suggested by Kindt et al.
Collagen molecules have a triple-helical structure and the presence of 4-hydroxyproline
resulting from a posttranslational modification of peptide-bound prolyl residues provides a distinctive marker of these molecules .
A single peptide chain of collagen ([alpha]-chain) is comprised of 33% glycine (G), 10% proline (P), and 10% hydroxyproline (HyP) in a distinctive repeating pattern of [(glycine-X-Y).sub.n], where X is frequently proline and Y is frequently 4-hydroxyproline
(some 3-hydroxyproline or 5-hydroxylysine).
Collagen chains that do not contain 4-hydroxyproline
cannot fold into triple helical molecules that are stable at body temperature (Pihlajaniemi et al.
(13,14) Collagen contains 12% of the aminoacid proline and 9% of 4-hydroxyproline
. Silica increases synthesis of proline from glutamic acid.
Table I Concentration of amino acids detected in the hydrolyzed less than 1 kDa fraction of an aqueous Laurencia poitei extract Compound Concentration ([[micro]molar]) Glutamine/Glutamate 46 Glycine 33 Alanine 19 Asparagine/Aspartate 18 Serine 14 Threonine 12 Homoserine 8.2 Valine 6.6 4-Hydroxyproline
6.2 Histidine 5.4 Leucine 4.4 Isoleucine 4.2 Hydroxylysine 3.6 Lysine 3.6 Arginine 3.0 Phenylalanine 2.8 Methionine 1.4 Only amino acids detected at concentrations greater than I [[micro]molar] are listed.
One of the overrepresented functional groups in cluster 3 shows enrichment for functions related to biological adhesion, lipid catabolic process, and 4-hydroxyproline