Calcium supplements increase the serum levels of crosslinked N-telopeptides of bone collagen and parathyroid hormone in rachitic Nigerian children.
OBJECTIVE
Biochemical markers of bone turnover were measured in the sera of 16 controls and 10 children with calcium-deficiency rickets, during a 12-week course of calcium supplementation (1 g CaCO3/d) that was effective in healing the bone lesions of the rachitic children.


METHODS
Serum levels of crosslinked N-telopeptides of bone collagen (NTx), parathyroid hormone (PTH), alkaline phosphatase (ALP), and urinary deoxypyridinoline (LP) were assayed at baseline and during the course of calcium therapy and compared with data of the 16 non-rachitic controls.


RESULTS
Calcium therapy suppressed serum NTx and PTH levels in the rachitic children within 24 h; however, after the first week, PTH and NTx levels increased to the extent that at 12 weeks both were elevated when compared with controls or to baseline levels. Serum levels of NTx and PTH were correlated in the controls and experimental subjects (r = 0.63, p < 0.001).


CONCLUSIONS
The rate of bone resorption, as estimated by serum NTx concentration, is increased during the healing of rachitic lesions.
Department of Biochemistry and Molecular Biology, University of New Mexico School of Medicine, Albuquerque 87131, USA.
J K
JK
Scariano
D J
DJ
Vanderjagt
T
T
Thacher
C O
CO
Isichei
B W
BW
Hollis
R H
RH
Glew
D000469:Alkaline Phosphatase / Q000097:blood; D000596:Amino Acids / Q000652:urine; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001842:Bone and Bones / Q000378:metabolism; D002118:Calcium / Q000097:blood / Q000172:deficiency* / Q000627:therapeutic use*; D002122:Calcium Chloride / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003094:Collagen / Q000097:blood*; D024042:Collagen Type I; D003404:Creatinine / Q000652:urine; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005527:Food, Fortified; D006801:Humans; D008297:Male; D009549:Nigeria; D010281:Parathyroid Hormone / Q000097:blood*; D010455:Peptides / Q000097:blood*; D010758:Phosphorus / Q000097:blood; D011863:Radioimmunoassay / Q000379:methods; D012016:Reference Values; D012044:Regression Analysis; D012279:Rickets / Q000097:blood / Q000188:drug therapy* / Q000652:urine; D013997:Time Factors
D000596:Amino Acids; D015415:Biomarkers; D024042:Collagen Type I; D010281:Parathyroid Hormone; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D010758:Phosphorus; C036020:deoxypyridinoline; D003094:Collagen; D003404:Creatinine; D000469:Alkaline Phosphatase; D002122:Calcium Chloride; D002118:Calcium