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. 1969 Apr;48(4):607–612. doi: 10.1172/JCI106019

Bone matrix turnover and balance in vitro

II. The effects of ageing

Barry Flanagan 1,2,3, George Nichols Jr 1,2,3
PMCID: PMC322266  PMID: 5774103

Abstract

The rates of both formation and resorption of bone collagen may be accurately quantitated by kinetic analysis of hydroxyproline metabolism in vitro. Using this approach we have studied the changes in bone collagen turnover with age in the rat. The rates of synthesis and resorption of collagen decline with age although the resorptive activity per cell increases up to 6 months of age. The solubility of collagen declines with age. The fraction of the newly synthesized collagen which is deposited as matrix declines dramatically with age revealing a new and hitherto unsuspected aspect of the osteoporotic process. The collagen balance becomes progressively more negative over the 1st 6 months of life. These results indicate that even in an animal who is not subject to clinical osteoporosis, biochemical measurement reveals that such a trend exists. The application of this approach to human subjects is feasible and has important implications.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. BORLE A. B., NICHOLS N., NICHOLS G., Jr Metabolic studies of bone in vitro. I. Normal bone. J Biol Chem. 1960 Apr;235:1206–1210. [PubMed] [Google Scholar]
  2. CHINARD F. P. Photometric estimation of proline and ornithine. J Biol Chem. 1952 Nov;199(1):91–95. [PubMed] [Google Scholar]
  3. FLANAGAN B., NICHOLS G., Jr Metabolic studies of bone in vitro. IV. Collagen biosynthesis by surviving bone fragments in vitro. J Biol Chem. 1962 Dec;237:3686–3692. [PubMed] [Google Scholar]
  4. Flanagan B., Nichols G., Jr Bone matrix turnover and balance in vitro. I. The effects of parathyroid hormone and thyrocalcitonin. J Clin Invest. 1969 Apr;48(4):595–606. doi: 10.1172/JCI106018. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Flanagan B., Nichols G., Jr Metabolic studies of human bone in vitro. I. Normal bone. J Clin Invest. 1965 Nov;44(11):1788–1794. doi: 10.1172/JCI105286. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Flanagan B., Nichols G., Jr Metabolic studies of human bone in vitro. II. Changes in hyperparathyroidism. J Clin Invest. 1965 Nov;44(11):1795–1804. doi: 10.1172/JCI105287. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. GERBER G., GERBER G., ALTMAN K. I. Studies on the metabolism of tissue proteins. I. Turnover of collagen labeled with proline-U-C14 in young rats. J Biol Chem. 1960 Sep;235:2653–2656. [PubMed] [Google Scholar]
  8. HOWES E. L., MANDL I., ZAFFUTO S., ACKERMANN W. The use of Clostridium histolyticum enzymes in the treatment of experimental third degree burns. Surg Gynecol Obstet. 1959 Aug;109(2):177–188. [PubMed] [Google Scholar]
  9. Juva K., Prockop D. J. Modified procedure for the assay of H-3-or C-14-labeled hydroxyproline. Anal Biochem. 1966 Apr;15(1):77–83. doi: 10.1016/0003-2697(66)90249-1. [DOI] [PubMed] [Google Scholar]
  10. Nichols G., Jr, Flanagan B. Osteoporosis--a disorder of bone cell metabolism. Fed Proc. 1966 May-Jun;25(3):922–927. [PubMed] [Google Scholar]
  11. PROCKOP D. J., UDENFRIEND S. A specific method for the analysis of hydroxyproline in tissues and urine. Anal Biochem. 1960 Nov;1:228–239. doi: 10.1016/0003-2697(60)90050-6. [DOI] [PubMed] [Google Scholar]
  12. SPRAY C. M., WIDDOWSON E. M. The effect of growth and development on the composition of mammals. Br J Nutr. 1950;4(4):332–353. doi: 10.1079/bjn19500058. [DOI] [PubMed] [Google Scholar]

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