Quantifying the Fast Dynamics of HClO in Living Cells
by a Fluorescence Probe Capable of Responding to Oxidation and Reduction
Events within the Time Scale of Milliseconds
posted on 2020-09-07, 17:35authored byPeng Li, Yan Jia, Ningjiu Zhao, Yanan Zhang, Panwang Zhou, Zhangrong Lou, Yan Qiao, Peiyu Zhang, Shuhao Wen, Keli Han
The biological roles
of reactive oxygen species (ROS) depend highly on their dynamics.
However, it has been challenging for measuring the dynamics of ROS
in cells. In this study, we address a core challenge in developing
fluorescence probes for monitoring ROS dynamics by designing a redox
couple that can respond rapidly to both oxidation and reduction events.
We show that such molecules can be designed by taking advantage of
the steric effects of electron-donating groups at the ortho position
relative to the selenium center. We demonstrate this design in a new
fluorescence probe named Fl-Se. Results reveal that Fl-Se and its
oxidized product Fl-SeO rapidly respond to HClO, an important member
of the ROS family, and glutathione (GSH), with t1/2 = 2.7 ms at [HClO] = 1 μM; t1/2 = 61 ms at [GSH] = 1 mM. When applied in cells, Fl-Se satisfactorily
tracks the dynamics of intracellular HClO in H2O2-stimulated HL-60 cells, as well as the different dynamic behaviors
of HClO fluctuations involved in the phorbol 12-myristate-13-acetate-activated
immune response of RAW264.7 cells and the 3-deazaneplanocin A-induced
apoptosis of HL 60 cells.