Chung H, Kang Y S, Hwang C S, Moon I K, Yim C H, Choi K H, Han K O, Jang H C, Yoon H K, Han I K
Department of Medicine, Sungkyunkwan University School of Medicine, Samsung Cheil Hospital, Seoul, Korea.
J Korean Med Sci. 2001 Dec;16(6):769-73. doi: 10.3346/jkms.2001.16.6.769.
Information on precise effects of deflazacort on bone cell function, especially osteoclasts, is quite limited. Therefore, the present study was undertaken to test effects of deflazacort on osteoclast-like cell formation in mouse bone marrow cultures and on the regulation of osteoprotegerin (OPG) and its ligand (RANKL) mRNA expressions by RT-PCR in the ST2 marrow stromal cells. TRAP-positive mononuclear cells increased after the treatment of deflazacort at 10(-9) to 10(-7) M alone for 6 days in a dose-dependent manner. Number of TRAP-positive multi-nucleated cells (MNCs) increased significantly with combined treatment of deflazacort at 10(-7) M and 1,25-(OH)2D3 at 10(-9) M compared to that of cultures treated with 1,25-(OH)2D3 alone (p<0.05). Exposure to deflazacort at 10(-7) M in the presence of 1,25-(OH)2D3 at 10(-9) M in the last 3-day culture had greater stimulatory effect on osteoclast-like cell formation than that of the first 3-day culture did. Deflazacort at 10(-10) -10(-6) M downregulated OPG and upregulated RANKL in mRNA levels in a dose-dependent manner. These observations suggest that deflazacort stimulate osteoclast precursor in the absence of 1,25-(OH)2D3 and enhance differentiation of osteoclasts in the presence of 1,25-(OH)2D3. These effects are, in part, thought to be mediated by the regulation of the expression of OPG and RANKL mRNA in marrow stromal cells.
关于地夫可特对骨细胞功能，尤其是破骨细胞的确切影响的信息非常有限。因此，本研究旨在测试地夫可特对小鼠骨髓培养物中破骨细胞样细胞形成的影响，以及通过逆转录聚合酶链反应（RT-PCR）检测地夫可特对ST2骨髓基质细胞中骨保护素（OPG）及其配体（RANKL）mRNA表达的调节作用。单独用10(-9)至10(-7)M的地夫可特处理6天后，抗酒石酸酸性磷酸酶（TRAP）阳性单核细胞呈剂量依赖性增加。与单独用1,25-(OH)2D3处理的培养物相比，10(-7)M的地夫可特与10(-9)M的1,25-(OH)2D3联合处理时，TRAP阳性多核细胞（MNCs）的数量显著增加（p<0.05）。在最后3天的培养中，在10(-9)M的1,25-(OH)2D3存在下用10(-7)M的地夫可特处理，对破骨细胞样细胞形成的刺激作用比前3天的培养更大。10(-10)-10(-6)M的地夫可特以剂量依赖性方式下调OPG并上调RANKL的mRNA水平。这些观察结果表明，地夫可特在没有1,25-(OH)2D3的情况下刺激破骨细胞前体，并在有1,25-(OH)2D3的情况下增强破骨细胞的分化。这些作用部分被认为是通过调节骨髓基质细胞中OPG和RANKL mRNA的表达来介导的。
