Effect of 1,25(OH)2 vitamin D3 on circulating insulin-like growth factor-I and beta 2 microglobulin in patients with osteoporosis.
To test the hypothesis that growth factors mediate the stimulatory effect of 1,25(OH)2 vitamin D3 [1,25(OH)2D3] on bone remodeling in osteoporosis, the authors studied the effect of the secosteroid administration in two doses (1 microgram/day and 2 micrograms/day) for 14 days on circulating insulin-like growth factor-I (IGF-I), beta 2 microglobulin, and osteocalcin in 18 osteoporotic women. The biological effectiveness of the treatment was controlled by a decline of serum intact parathyroid hormone. Compared with the values before treatment, 1,25(OH)2D3 increased means of plasma IGF-I, beta 2 microglobulin, and serum osteocalcin significantly; however, the effects were only apparent after the higher dose of the drug (169 +/- 26 versus 134 +/- 28 ng/ml, P < 0.01; 2.08 +/- 0.1 versus 1.92 +/- 0.1 micrograms/ml, P < 0.05; and 8.5 +/- 1.3 versus 5.4 +/- 1.1 ng/ml, P < 0.01, respectively). The authors conclude that exogenous 1,25(OH)2D3 promotes the production of IGF-I and beta 2 microglobulin in osteoporotic patients in parallel to the marker of osteoblastic function, osteocalcin, which supports the tested hypothesis.
Zofková
I
I
Institute of Endocrinology, Prague I, Czech Republic.
Kancheva
R L
RL
Bendlová
B
B
D002117:Calcitriol / Q000097:blood / Q000494:pharmacology*; D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000096:biosynthesis / Q000187:drug effects*; D008875:Middle Aged; D015675:Osteocalcin / Q000096:biosynthesis / Q000187:drug effects*; D010024:Osteoporosis / Q000097:blood / Q000188:drug therapy*; D010281:Parathyroid Hormone / Q000097:blood; D001613:beta 2-Microglobulin / Q000096:biosynthesis / Q000187:drug effects*
D010281:Parathyroid Hormone; D001613:beta 2-Microglobulin; D015675:Osteocalcin; D007334:Insulin-Like Growth Factor I; D002117:Calcitriol; D002118:Calcium