Cell Physiology Research Group, Department of Physiology, University of Extremadura, Caceres, Spain.
DNA Cell Biol. 2013 Apr;32(4):147-55. doi: 10.1089/dna.2012.1939. Epub 2013 Mar 15.
The seleno-organic compound and radical scavenger ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one) have been extensively employed as an anti-inflammatory and neuroprotective compound. However, its glutathione peroxidase activity at the expense of cellular thiols groups could underlie certain deleterious actions of the compound on cell physiology. In this study, we have analyzed the effect of ebselen on rat hippocampal astrocytes in culture. Cellular viability, the intracellular free-Ca(2+) concentration ([Ca(2+)]c), the mitochondrial free-Ca(2+) concentration ([Ca(2+)]m), and mitochondrial membrane potential (ψm) were analyzed. The caspase-3 activity was also assayed. Our results show that cell viability was reduced by treatment of cells with ebselen, depending on the concentration employed. In the presence of ebselen, we observed an initial transient increase in [Ca(2+)]c that was then followed by a progressive increase to an elevated plateau. We also observed a transient increase in [Ca(2+)]m in the presence of ebselen that returned toward a value over the prestimulation level. The compound induced depolarization of ψm and altered the permeability of the mitochondrial membrane. Additionally, a disruption of the mitochondrial network was observed. Finally, we did not detect changes in caspase-3 activation in response to ebselen treatment. Collectively, these data support the likelihood of ebselen, depending on the concentration employed, reduces viability of rat hippocampal astrocytes via its action on the mitochondrial activity. These may be early effects that do not involve caspase-3 activation. We conclude that, depending on the concentration used, ebselen might exert deleterious actions on astrocyte physiology that could compromise cell function.
硒有机化合物和自由基清除剂依布硒啉（2-苯-1,2-苯并异硒唑-3（2H）-酮）已被广泛用作抗炎和神经保护化合物。然而，其谷胱甘肽过氧化物酶活性以细胞硫醇基团为代价，可能是该化合物对细胞生理学产生某些有害作用的基础。在这项研究中，我们分析了依布硒啉对培养的大鼠海马星形胶质细胞的影响。分析了细胞活力、细胞内游离钙浓度([Ca2+]c)、线粒体游离钙浓度([Ca2+]m)和线粒体膜电位(ψm)。还测定了半胱天冬酶-3 的活性。我们的结果表明，细胞活力随依布硒啉浓度的增加而降低。在依布硒啉存在的情况下，我们观察到[Ca2+]c 的初始短暂增加，随后逐渐增加到升高的平台。我们还观察到依布硒啉存在时[Ca2+]m 的短暂增加，随后恢复到刺激前水平。该化合物诱导ψm 的去极化并改变线粒体膜的通透性。此外，还观察到线粒体网络的破坏。最后，我们没有检测到依布硒啉处理后 caspase-3 激活的变化。总的来说，这些数据支持了依布硒啉的可能性，取决于所使用的浓度，通过其对线粒体活性的作用降低大鼠海马星形胶质细胞的活力。这些可能是不涉及半胱天冬酶-3 激活的早期效应。我们得出结论，依布硒啉可能根据所用浓度对星形胶质细胞生理学产生有害作用，从而损害细胞功能。
