Inaba M, Okuno S, Nishizawa Y, Yukioka K, Otani S, Matsui-Yuasa I, Morisawa S, DeLuca H F, Morii H
Second Department of Internal Medicine, Osaka City University Medical School, Japan.
Arch Biochem Biophys. 1987 Nov 1;258(2):421-5. doi: 10.1016/0003-9861(87)90363-8.
Vitamin D compounds added to the culture medium induce HL-60 cells to differentiate into macrophage/monocytes via a receptor mechanism. This system provides a biologically relevant assay for the study of biopotency of vitamin D analogs. Using this system, the biological activity of various fluorinated derivatives of vitamin D3 was compared with that of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3). As assessed by cell morphology, nitroblue tetrazolium reduction and nonspecific esterase activity, 26,26,26,27,27,27-hexafluoro-1,25-dihydroxyvitamin D3 (26,27-F6-1,25-(OH)2D3) and 26,26,26,27,27,27-hexafluoro-1,24-dihydroxyvitamin D3 (26,27-F6-1,24-(OH)2D3) were about 10 times as potent as 1,25-(OH)2D3 in suppressing HL-60 cell proliferation and inducing cell differentiation. The biological activity of 26,26,26,27,27,27-hexafluoro-1-hydroxyvitamin D3 (26,27-F6-1-OH-D3) was equal to that of 1,25-(OH)2D3 in this system. 1,25-(OH)2D3 and its fluorinated analogs exerted their effects on HL-60 cells in a dose-dependent manner. HL-60 cells have a specific receptor for 1,25-(OH)2D3 with an apparent Kd of 0.25 nM, identical with that of chick intestinal receptor. While the binding affinities of 26,27-F6-1,25-(OH)2D3 and 26,27-F6-1,24-(OH)2D3 for chick intestinal receptor were lower than that of 1,25-(OH)2D3 by factors of 3 and 1.5, respectively, they were as competent as 1,25-(OH)2D3 in binding to HL-60 cell receptor. The ability of 26,27-F6-1-OH-D3 to compete for receptor protein from HL-60 cells and chick intestine was about 1/70 that of 1,25-(OH)2D3. These results indicate that trifluorination of carbons 26 and 27 of vitamin D3 can markedly enhance the effect on HL-60 cells.
添加到培养基中的维生素D化合物通过受体机制诱导HL-60细胞分化为巨噬细胞/单核细胞。该系统为研究维生素D类似物的生物活性提供了一种生物学相关的检测方法。利用该系统，将维生素D3的各种氟化衍生物的生物活性与1,25-二羟基维生素D3（1,25-(OH)2D3）进行了比较。通过细胞形态学、硝基蓝四氮唑还原和非特异性酯酶活性评估，26,26,26,27,27,27-六氟-1,25-二羟基维生素D3（26,27-F6-1,25-(OH)2D3）和26,26,26,27,27,27-六氟-1,24-二羟基维生素D3（26,27-F6-1,24-(OH)2D3）在抑制HL-60细胞增殖和诱导细胞分化方面的效力约为1,25-(OH)2D3的10倍。26,26,26,27,27,27-六氟-1-羟基维生素D3（26,27-F6-1-OH-D3）在该系统中的生物活性与1,25-(OH)2D3相当。1,25-(OH)2D3及其氟化类似物对HL-60细胞的作用呈剂量依赖性。HL-60细胞具有1,25-(OH)2D3的特异性受体，其表观解离常数（Kd）为0.25 nM，与鸡肠道受体的相同。虽然26,27-F6-1,25-(OH)2D3和26,27-F6-1,24-(OH)2D3对鸡肠道受体的结合亲和力分别比1,25-(OH)2D3低3倍和1.5倍，但它们与HL-60细胞受体结合的能力与1,25-(OH)2D3相当。26,27-F6-1-OH-D3从HL-60细胞和鸡肠道竞争受体蛋白的能力约为1,25-(OH)2D3的1/70。这些结果表明，维生素D3的26和27位碳的三氟化可显著增强对HL-60细胞的作用。
