Sortino M A, Aleppo G, Scapagnini U, Canonico P L
Institute of Pharmacology, University of Catania, School of Medicine, Italy.
Eur J Pharmacol. 1992 Jul 1;226(3):273-7. doi: 10.1016/0922-4106(92)90072-4.
The mechanism of action of ipriflavone, an isoflavone derivative, was studied in the osteoblastic-like UMR-106 cell line. Ipriflavone affected both phosphoinositide hydrolysis and 45Ca2+ uptake. A repeated treatment of UMR-106 cells (once a day, for 3 days) with ipriflavone decreased, in a concentration-dependent manner, [3H]inositol monophosphate accumulation. This effect was also achieved after single addition of high concentrations of ipriflavone or 100 nM [Asu1,7]eel-calcitonin, a semi-synthetic analog of eel calcitonin. When repeatedly added to UMR-106 cells, 17 beta-estradiol produced a marked inhibition of [3H]inositol monophosphate accumulation, an effect which appeared significant only at a concentration of 1 microM and which was accompanied by a reduced incorporation of [3H]inositol into membrane phospholipids. A repeated treatment with ipriflavone reduced 45Ca2+ uptake as well. This effect was observed also after a single addition of [Asu1,7]eel-calcitonin but not following single or repeated treatment with 17 beta-estradiol. The present data indicate the osteoblast as a direct and specific target for ipriflavone and suggest that this compound may share intracellular transducing mechanisms with other antiosteoporotic hormones such as estrogen and calcitonin.
在成骨样UMR-106细胞系中研究了异黄酮衍生物依普黄酮的作用机制。依普黄酮影响磷酸肌醇水解和45Ca2+摄取。用依普黄酮对UMR-106细胞进行重复处理（每天一次，共3天），以浓度依赖的方式降低了[3H]肌醇单磷酸的积累。在单次添加高浓度的依普黄酮或100 nM [Asu1,7]鳗鱼降钙素（鳗鱼降钙素的半合成类似物）后也能达到这种效果。当反复添加到UMR-106细胞中时，17β-雌二醇对[3H]肌醇单磷酸的积累产生了显著抑制，这种效应仅在浓度为1 microM时才显著，并且伴随着[3H]肌醇掺入膜磷脂的减少。用依普黄酮进行重复处理也降低了45Ca2+摄取。在单次添加[Asu1,7]鳗鱼降钙素后也观察到了这种效应，但在单次或重复用17β-雌二醇处理后未观察到。目前的数据表明成骨细胞是依普黄酮的直接和特异性靶点，并表明该化合物可能与其他抗骨质疏松激素如雌激素和降钙素共享细胞内转导机制。
