Department of Biomedical and Chemical Engineering, Syracuse University, 303C Bowne Hall, Syracuse, NY 13244, USA; Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA.
Acta Biomater. 2013 Nov;9(11):9220-8. doi: 10.1016/j.actbio.2013.06.040. Epub 2013 Jul 4.
The physico-chemical processes and phenomena occurring at the interface of metallic biomedical implants and the body dictate their successful integration in vivo. Changes in the surface potential and the associated redox reactions at metallic implants can significantly influence several aspects of biomaterial/cell interactions such as cell adhesion and survival in vitro. Accordingly, there is a voltage viability range (voltages which do not compromise cellular viability of the cells cultured on the polarized metal) for metallic implants. We report on cellular dynamics (size, polarity, movement) and temporal changes in the number and total area of focal adhesion complexes in transiently transfected MC3T3-E1 pre-osteoblasts cultured on CoCrMo alloy surfaces polarized at the cathodic and anodic edges of its voltage viability range (-400 and +500 mV (Ag/AgCl), respectively). Nucleus dynamics (size, circularity, movement) and the release of reactive oxygen species (ROS) were also studied on the polarized metal at -1000, -400 and +500 mV (Ag/AgCl). Our results show that at -400 mV, where reduction reactions dominate, a gradual loss of adhesion occurs over 24 h while cells shrink in size during this time. At +500 mV, where oxidation reactions dominate (i.e. metal ions form, including Cr6+), cells become non-viable after 5h without showing any significant changes in adhesion behavior right before cell death. Nucleus size of cells at -1000 mV decreased sharply within 15 min after polarization, which rendered the cells completely non-viable. No significant amount of ROS release by cells was detected on the polarized CoCrMo at any of these voltages.
金属生物医学植入物与人体界面处发生的物理化学过程和现象决定了它们在体内的成功整合。金属植入物表面电位的变化和相关的氧化还原反应会显著影响生物材料/细胞相互作用的几个方面，如体外细胞黏附和存活。因此，金属植入物存在一个电压存活范围（不会损害在极化金属上培养的细胞活力的电压）。我们报告了瞬时转染的 MC3T3-E1 前成骨细胞在 CoCrMo 合金表面上培养时的细胞动力学（大小、极性、运动）和焦点黏附复合物数量和总面积的时间变化，该合金表面在其电压存活范围内的阴极和阳极边缘（分别为-400 和+500 mV（Ag/AgCl））进行极化。还在-1000、-400 和+500 mV（Ag/AgCl）的极化金属上研究了细胞核动力学（大小、圆度、运动）和活性氧物质（ROS）的释放。我们的结果表明，在还原反应占主导地位的-400 mV 下，随着时间的推移，黏附逐渐丧失，而细胞在此期间体积缩小。在+500 mV 下，氧化反应占主导地位（即金属离子形成，包括 Cr6+），细胞在 5 小时后变得不可存活，而在细胞死亡之前，黏附行为没有显示出任何明显变化。极化后 15 分钟内，-1000 mV 下细胞的细胞核大小急剧减小，使细胞完全失去活力。在任何这些电压下，极化 CoCrMo 上的细胞都没有检测到大量 ROS 释放。
