A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia.
Biological Faculty, Lomonosov Moscow State University, 119992 Moscow, Russia.
Int J Mol Sci. 2022 Jan 1;23(1):482. doi: 10.3390/ijms23010482.
The mitochondrial membrane potential (∆Ψ) is the driving force providing the electrical component of the total transmembrane potential of hydrogen ions generated by proton pumps, which is utilized by the ATP synthase. The role of ∆Ψ is not limited to its role in bioenergetics since it takes part in other important intracellular processes, which leads to the mandatory requirement of the homeostasis of ∆Ψ. Conventionally, ∆Ψ in living cells is estimated by the fluorescence of probes such as rhodamine 123, tetramethylrodamine, etc. However, when assessing the fluorescence, the possibility of the intracellular/intramitochondrial modification of the rhodamine molecule is not taken into account. Such changes were revealed in this work, in which a comparison of normal (astrocytic) and tumor (glioma) cells was conducted. Fluorescent microscopy, flow cytometry, and mass spectrometry revealed significant modifications of rhodamine molecules developing over time, which were prevented by amiodarone apparently due to blocking the release of xenobiotics from the cell and their transformation with the participation of cytochrome P450. Obviously, an important role in these processes is played by the increased retention of rhodamines in tumor cells. Our data require careful evaluation of mitochondrial ∆Ψ potential based on the assessment of the fluorescence of the mitochondrial probe.
线粒体膜电位 (∆Ψ) 是质子泵产生的氢离子跨膜总氢离子势能的驱动力，该势能被 ATP 合酶利用。∆Ψ 的作用不仅限于其在生物能量学中的作用，因为它参与了其他重要的细胞内过程，这导致了 ∆Ψ 的动态平衡的强制性要求。传统上，活细胞中的 ∆Ψ 通过荧光探针（如罗丹明 123、四甲基罗丹明等）来估计。然而，在评估荧光时，并没有考虑到罗丹明分子的细胞内/线粒体修饰的可能性。在这项工作中揭示了这种变化，其中对正常（星形胶质细胞）和肿瘤（神经胶质瘤）细胞进行了比较。荧光显微镜、流式细胞术和质谱分析显示，罗丹明分子随着时间的推移发生了显著的修饰，而胺碘酮显然通过阻止细胞中外来物质的释放及其与细胞色素 P450 参与的转化来防止这些修饰。显然，在这些过程中，肿瘤细胞中罗丹明的保留增加起着重要作用。我们的数据需要基于线粒体探针荧光评估来仔细评估线粒体 ∆Ψ 潜能。
