EFFECTS OF PHYTOESTROGEN ON BONE LOSS IN OVARIECTOMIZED MICE.

染料木素是一种在大豆中大量存在的异黄酮，其结构与雌激素相似，表明染料木素可能具有植物雌激素的作用。为了研究染料木黄酮在造血和骨代谢中的可能作用，采用假手术或去卵巢（OVX）雌性小鼠，选择OVX小鼠，通过微渗透泵皮下注射染料木黄酮（0.1-0.7 mg/d）或17β-雌二醇（0.01-0.1 μg/d） 2-4周。在OVX小鼠中，子宫重量下降，但E2给药后完全恢复。相反，染料木黄酮对ovx诱导的子宫萎缩没有逆转作用。OVX术后2 ~ 4周骨髓细胞数量明显增加，且以b220弱阳性前b细胞居多。E2和染料木素均可完全恢复增加的b淋巴生成。在OVX小鼠中，通过mCT扫描和双能x线吸收仪测量，股骨远端干骺端小梁体积明显减少，染料木素和E2恢复了这一点。这些结果表明染料木素在骨和骨髓中表现出雌激素作用，调节b淋巴细胞生成和防止骨质流失，而在子宫中没有雌激素作用。植物雌激素可能是子宫内有用的雌激素作用。植物雌激素可能有助于防止因雌性激素缺乏而导致的骨质流失。

Genistein, an isoflavone abundantly present in soybeans, has structural similarity to estrogen, suggesting that genistein may act as a phytoestrogen. To examine the possible role of genistein in hemopoiesis and bone metabolism, female mice were either sham-operated or ovariectomized (OVX), and selected OVX mice were administered genistein for 2-4 weeks (0.1-0.7 mg/day) or 17β-estradiol (E2) (0.01-0.1 μg/day) subcutaneously, using a mini-osmotic pump. In OVX mice, uterine weight declined, but was completely restored by E2 administration. In contrast, genistein did not demonstrate a reversal of the OVX-induced uterine atrophy. The number of bone marrow cells markedly increased 2-4 weeks after OVX, and most of these were B220-weakly positive pre-B cells. The increased B-lymphopoiesis was completely restored not only by E2, but also by genistein administration. In OVX mice, the trabecular one volume of the femoral distal metaphysis, measured by mCT scanning and dual energy X-ray absorptiometry, was markedly reduced, and genistein restored this, as did E2. These results indicate that genistein exhibits estrogenic action in bone and bone marrow to regulate B-lymphopoiesis and prevent bone loss, without exhibiting estrogenic action in the uterus. Phytoestrogens may be useful estrogenic action in the uterus. Phytoestrogens may be useful for preventing bone loss due to estrogen deficiency in females.