Pfeilschifter J, Diel I, Pilz U, Brunotte K, Naumann A, Ziegler R
Department of Internal Medicine I, University Hospital, Heidelberg, Germany.
J Bone Miner Res. 1993 Jun;8(6):707-17. doi: 10.1002/jbmr.5650080609.
Bone loss with aging may at least in part be due to inadequate bone formation. In this study, we examined whether the proliferation of osteoblast-like cells in vitro in response to local and systemic factors might be attenuated with age. A total of 36 cultures of osteoblast-like cells were obtained from outgrowths of human trabecular bone. Parathyroid hormone, growth hormone, calcitonin, transforming growth factor beta, insulin-like growth factor I, and platelet-derived growth factor BB dose dependently increased DNA synthesis in all cultures. Increases in DNA synthesis with each of these factors were significantly negatively correlated with donor age in cultures obtained from the iliac crest bone of 50- to 70-year-old women. Cells from 61- to 70-year-old donors required approximately 10-fold higher concentrations of growth factors and hormones to yield comparable increases in DNA synthesis than cells from 51- to 60-year-old donors. A significant negative correlation between age and mitogenic responsiveness to platelet-derived growth factor and growth hormone, but not toward the other factors, was also observed in cultures from the femoral head trabecular bone of 60- to 90-year-old women. Our findings suggest that bone loss with aging may be partially due to a decreased capacity of osteoblasts to proliferate in response to systemic or locally released osteotropic factors.
随着年龄增长出现的骨质流失至少部分可能是由于骨形成不足。在本研究中，我们检测了体外成骨样细胞对局部和全身因素的增殖反应是否会随年龄增长而减弱。总共从人小梁骨的生长物中获得了36个成骨样细胞培养物。甲状旁腺激素、生长激素、降钙素、转化生长因子β、胰岛素样生长因子I和血小板衍生生长因子BB在所有培养物中均剂量依赖性地增加DNA合成。在从50至70岁女性的髂嵴骨获得的培养物中，这些因素各自引起的DNA合成增加与供体年龄显著负相关。与51至60岁供体的细胞相比，61至70岁供体的细胞需要大约高10倍浓度的生长因子和激素才能产生相当的DNA合成增加。在60至90岁女性股骨头小梁骨的培养物中，也观察到年龄与对血小板衍生生长因子和生长激素的促有丝分裂反应之间存在显著负相关，但与其他因素无关。我们的研究结果表明，随着年龄增长出现的骨质流失可能部分是由于成骨细胞对全身或局部释放的促骨生长因子的增殖能力下降。
