Wang Ting, Zhang Jin-Chao, Chen Yao, Xiao Pei-Gen, Yang Meng-Su
Institute of Medicinal Plant, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100094, China.
J Trace Elem Med Biol. 2007;21(2):84-91. doi: 10.1016/j.jtemb.2007.01.002. Epub 2007 Mar 13.
A series of experimental methods including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test, alkaline phosphatase (ALP) activity measurement and Oil Red O stain and measurement were employed to assess the effect of zinc ion on the osteogenic and adipogenic differentiation of mouse primary bone marrow stromal cells (MSCs) and the adipogenic trans-differentiation of mouse primary osteoblasts. The results showed that except for individual concentrations of zinc ion there was no effect on the proliferation of MSCs and osteoblasts. Zinc ion inhibited the osteogenic differentiation of MSCs at all the concentrations tested. It also inhibited adipogenic differentiation at all concentrations tested except 10(-9)mol/L. Both of the inhibition effects were attenuated with time increasing. Zinc ion depressed adipocytic trans-differentiation of osteoblasts at concentrations of 10(-11) and 10(-10)mol/L, but the effect could be reversed to promote or even be removed when concentration was increased. It suggests that the influence of zinc ion on osteogenic, adipogenic differentiation of MSCs and adipocytic trans-differentiation of osteoblasts depends on zinc ion concentrations and incubation time. The protective effects of zinc ion on bone may be mediated by modulating differentiation of MSCs away from the adipocytes and inhibiting adipocytic trans-differentiation of osteoblasts. This may in turn promote osteoblast formation and reduce secretion of cytokines which may inhibit osteoclast formation and activation. These findings may be valuable for better understanding the mechanism of the effect of zinc ion on bone.
采用一系列实验方法，包括3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)试验、碱性磷酸酶(ALP)活性测定以及油红O染色和测定，以评估锌离子对小鼠原代骨髓基质细胞(MSCs)成骨和成脂分化以及小鼠原代成骨细胞成脂转分化的影响。结果表明，除个别锌离子浓度外，对MSCs和成骨细胞的增殖无影响。在所有测试浓度下，锌离子均抑制MSCs的成骨分化。除10(-9)mol/L外，在所有测试浓度下它也抑制成脂分化。两种抑制作用均随时间增加而减弱。在10(-11)和10(-10)mol/L浓度下，锌离子抑制成骨细胞的脂肪细胞转分化，但当浓度增加时，这种作用可逆转以促进甚至消除。这表明锌离子对MSCs成骨、成脂分化以及成骨细胞脂肪细胞转分化的影响取决于锌离子浓度和孵育时间。锌离子对骨骼的保护作用可能是通过调节MSCs向远离脂肪细胞的方向分化并抑制成骨细胞的脂肪细胞转分化来介导的。这反过来可能促进成骨细胞形成并减少可能抑制破骨细胞形成和激活的细胞因子的分泌。这些发现可能有助于更好地理解锌离子对骨骼作用的机制。
