G. Khastgir et al., Anabolic effect of long-term estrogen replacement on bone collagen in elderly postmenopausal women with osteoporosis, OSTEOPOR IN, 12(6), 2001, pp. 465-470
Estrogen has been shown to stimulate osteoblasts in cell culture and increa
se bone formation in animal models. Such an anabolic effect of estrogen rep
lacement therapy (ERT) would be beneficial to postmenopausal women with ost
eoporosis. Hence, we assessed the total collagen content and collagen cross
link maturity in iliac crest bone biopsy from 18 such women before and afte
r 6 years of higher-dose ERT. These results were compared with the serum es
tradiol level and bone mineral density (BMD). Total collagen content of bot
h cortical and cancellous bone increased, showing a median (95% CI) percent
change of 6.7 (0.3-14.2) and 25.6 (13.5-33.8), respectively. Increase in c
ollagen synthesis was supported by a rise in intermediate crosslinks in bot
h cortical and cancellous bone, and mature crosslinks in cortical bone only
. At the same time, BMD showed a substantial rise both at the lumbar spine
and proximal femur with a median (95% CI) percent change of 28.6 (19.8-37.3
) and 14.5 (8.4-20.7), respectively. Serum estradiol and BMD results correl
ated with cortical bone collagen levels. Our results suggest that long-term
higher-dose ERT has a therapeutic role due to its anabolic effect on bone
in postmenopausal women with osteoporosis.