Quantitative kinetics of intracellular singlet oxygen generation using a fluorescence probe

Area of Science:

• Biochemistry
• Cell Biology
• Chemical Biology

Background:

• Singlet oxygen (¹O₂) is a reactive oxygen species implicated in physiological processes.
• Increased ¹O₂ oxidation products are observed in prediabetes, highlighting its potential as a biomarker.
• The rapid generation and quenching of ¹O₂ in biological systems limit understanding of its dynamic changes in living cells.

Purpose of the Study:

• To investigate the quantification of ¹O₂ generation kinetics in mammalian cells.
• To explore the utility of the far-red fluorescent probe Si-DMA for monitoring mitochondrial ¹O₂.
• To assess the impact of ¹O₂ generators and quenchers on cellular fluorescence.

Main Methods:

• Utilized a far-red fluorescent probe, Si-DMA, for mitochondrial ¹O₂ detection.
• Applied time-lapse imaging to monitor dynamic changes in Si-DMA fluorescence intensity.
• Administered the ¹O₂ generator endoperoxide and ¹O₂ quenchers to mammalian cells.

Main Results:

• Si-DMA fluorescence intensity increased dose-dependently following endoperoxide treatment in living cells.
• Treatment with ¹O₂ quenchers reduced fluorescence intensity after endoperoxide administration.
• Demonstrated the feasibility of quantifying intracellular ¹O₂ kinetics using Si-DMA and time-lapse imaging.

Conclusions:

• The Si-DMA probe enables real-time quantification of intracellular ¹O₂ generation kinetics.
• This approach provides novel insights into the mechanisms of ¹O₂ production in mammalian cells.
• Facilitates the study of ¹O₂ generators and quenchers in biological contexts.