A selective and sensitive method for quantification of endogenous polysulfide production in biological samples

Area of Science:

• Biochemistry
• Analytical Chemistry
• Cellular Biology

Background:

• Hydrogen sulfide (H2S) acts as a gasotransmitter regulating cellular functions.
• H2S exerts biological effects indirectly through H2S-derived sulfane sulfur species/polysulfides.
• Detecting these reactive polysulfides in biological systems is analytically challenging due to their reactivity and limitations of current methods.

Purpose of the Study:

• To develop a sensitive, selective, and quantitative method for detecting endogenous polysulfides.
• To investigate the activity of H2S-generating enzymes in different murine organs.
• To identify the primary intracellular source of sulfane sulfur species/polysulfides.

Main Methods:

• Development of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) based assay.
• Utilized a novel reagent, Sulfane Sulfur Probe 4, for selective detection.
• Application of the method to various biological samples, including murine organs and cells.

Main Results:

• The developed LC-MS/MS method enables sensitive and quantitative detection of polysulfides in biological samples.
• Significant variability in H2S-generating enzyme activity was observed across different murine organs.
• Cystathionine γ-lyase was identified as the major intracellular source of polysulfides in murine endothelial cells and hearts.
• Intracellular polysulfide levels were detected in the nanomolar range.

Conclusions:

• The described LC-MS/MS method provides a robust tool for quantifying H2S-derived polysulfides.
• The findings highlight the organ-specific regulation of H2S-derived signaling.
• This method has the potential to significantly advance the understanding of H2S gasotransmission and its physiological roles.