D. Somjen, S. Katzburg, S. Tamir, O. Sharon, D. Hendel and Y. Vaya
Cultured female- derived human osteoblasts (hObs) responded by different parameters to the phytoestrogens: daidzein (D), glabrene (Gla) and glabridin (Glb), to their synthetic derivatives; carboxy-daidzein (cD) and to estradiol- 17? (E2). Since the skeletal protective effects of estrogens are not discernible in diabetic women, we tested the effects of these compounds on hObs grown in growth medium with high glucose (HG; 9.0g/L; 44 mM) compared to normal glucose (NG; 4.5g/L; 22 mM) using the stimulation of creatine kinase specific activity (CK) and 3[H] thymidine incorporation in to DNA (DNA) as hormonal responsiveness markers. HG slightly increased DNA and CK in hObs. Stimulations by E2 was abolished and by cD and D was slightly decreased in HG, but not by Gla and Glb in both age groups. Growing hObs in HG upregulated the expression of mRNA of both ER? and ER? in cells from pre- but not from post-menopausal women. Cells from both age groups express also mRNA for 25 hydroxy vitamin D3 1-? hydroxylase and showed enzymic activity which were down-regulated by HG in both age groups. Whether Gla and Glb act differentially via ERs and/or 1-? hydroxylase is not yet established.Since these compounds are active even in HG, they might be used for treating hyperglycemic/diabetic women.