Collagen-derived markers of bone metabolism in osteogenesis imperfecta.
Markers of bone formation [C-terminal and N-terminal propeptides of procollagen I (PICP, PINP), osteocalcin and alkaline phosphatase] and bone resorption [C-terminal cross-linked telopeptide of collagen I (ICTP) and hydroxypyridinium cross-links, pyridinoline (Pyr) and deoxypyridinoline (Dpyr)] were measured in 78 osteogenesis imperfecta (OI) patients to investigate bone metabolism in vivo and relate marker concentrations to phenotype and in vitro collagen I defects, as shown by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). PICP and PINP were generally low, and the serum levels were lower in all children and adults with mild OI and a quantitative collagen defect than in patients with severe OI and a qualitative collagen I defect. ICTP, Pyr and Dpyr were generally normal or reduced, but elevated in severely affected adults with a qualitative collagen I defect. The in vivo findings correlated with in vitro results of collagen I SDS-PAGE. Bone turnover is reduced in OI children and mildly affected OI adults, whereas bone resorption is elevated in severely affected adults. These findings may prove helpful for diagnosis and decision-making regarding therapy in OI.
Lund
A M
AM
Department of Clinical Genetics, Rigshospitalet, Copenhagen, Denmark.
Hansen
M
M
Kollerup
G
G
Juul
A
A
Teisner
B
B
Skovby
F
F
D000293:Adolescent; D015415:Biomarkers; D001862:Bone Resorption; D001842:Bone and Bones / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D003094:Collagen / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D010013:Osteogenesis Imperfecta / Q000378:metabolism*; D011347:Procollagen / Q000378:metabolism
D015415:Biomarkers; D011347:Procollagen; D003094:Collagen