The formation of electronically excited species in the human multiple myeloma cell suspension.
In this study, evidence is provided on the formation of electronically excited species in human multiple myeloma cells U266 in the growth medium exposed to hydrogen peroxide (H2O2). Two-dimensional imaging of ultra-weak photon emission using highly sensitive charge coupled device camera revealed that the addition of H2O2 to cell suspension caused the formation of triplet excited carbonyls (3)(R = O)*. The kinetics of (3)(R = O)* formation in the real time, as measured by one-dimensional ultra-weak photon emission using low-noise photomultiplier, showed immediate enhancement followed by a slow decay. In parallel to the formation of (3)(R = O)*, the formation of singlet oxygen ((1)O2) in U266 cells caused by the addition of H2O2 was visualized by the imaging of (1)O2 using the green fluorescence of singlet oxygen sensor green detected by confocal laser scanning microscopy. Additionally, the formation of (1)O2 after the addition of H2O2 to cell suspension was detected by electron paramagnetic resonance spin-trapping spectroscopy using 2,2,6,6-tetramethyl-4-piperidone. Presented results indicate that the addition of H2O2 to cell suspension results in the formation of (3)(R = O)* and (1)O2 in U266 cell suspension. The contribution of the cell-free medium to the formation of electronically excited species was discussed.
Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 11, 783 71 Olomouc, Czech Republic.
Marek
M
Rác
Department of Botany, Faculty of Science, Palacký University, Šlechtitelů 11, 783 71 Olomouc, Czech Republic.
Michaela
M
Sedlářová
Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 11, 783 71 Olomouc, Czech Republic.
Pavel
P
Pospíšil
D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004578:Electron Spin Resonance Spectroscopy; D055724:Electrophysiological Phenomena / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism* / Q000494:pharmacology; D018613:Microscopy, Confocal; D009101:Multiple Myeloma / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014407:Tumor Cells, Cultured
D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide