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Imaging Denatured Collagen Strands In vivo and Ex vivo via Photo-triggered Hybridization of Caged Collagen Mimetic Peptides
Published on: January 31, 2014
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Urinary polypeptides related to collagen synthesis.
The Journal of Clinical Investigation
|April 1, 1970
Summary
Urinary hydroxyproline polypeptides, fragments of collagen, may indicate new bone formation in skeletal disorders. Their ratio to total hydroxyproline can serve as an index of bone collagen synthesis.
Area of Science:
- Biochemistry
- Orthopedics
- Metabolic Bone Disease
Background:
- Urinary hydroxyproline is a marker for collagen turnover.
- A portion of urinary hydroxyproline exists as nondialyzable polypeptides.
- The origin and significance of these urinary collagen fragments were not fully understood.
Purpose of the Study:
- To characterize urinary hydroxyproline polypeptides.
- To investigate their relationship to collagen synthesis and bone metabolism.
- To determine if these peptides can serve as an index for new bone formation.
Main Methods:
- Gel filtration and ion exchange chromatography for polypeptide purification.
- Amino acid analysis and molecular weight determination.
- Administration of proline-(14)C to track hydroxyproline metabolism.
- Collagenase digestion to assess peptide structure.
- Analysis of urinary hydroxyproline fractions before and after parathyroid adenoma removal.
Main Results:
- Urinary hydroxyproline polypeptides resemble gelatin fragments with molecular weights of 4500-10,000.
- Proline-(14)C studies showed higher specific activity in polypeptide fractions, indicating their direct relation to active collagen synthesis.
- Collagenase digestion rendered these polypeptides dialyzable, confirming collagen-derived origin.
- Following parathyroid adenoma removal, total urinary hydroxyproline decreased, while the ratio of polypeptide fraction to total hydroxyproline increased significantly.
Conclusions:
- Urinary hydroxyproline polypeptides are fragments related to bone collagen synthesis.
- The ratio of these peptides to total urinary hydroxyproline may serve as a sensitive index of new bone formation.
- This finding has implications for monitoring skeletal disorders and bone metabolic activity.
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