Oxidation of Hydrogen Sulfide by Quinones: How Polyphenols Initiate Their Cytoprotective Effects
Abstract
:1. Introduction
2. Results
2.1. H2S Oxidation by Quinones and Hydroquinones
2.1.1. Polysulfide Production
Mechanism of Quinone-Catalyzed Polysulfide Production
O2 Dependency of H2S Oxidation
Effects of Superoxide Dismutase
Effects of ROS/Redox Scavengers on H2S Oxidation by 1,4-DB and Pyrogallol
2.1.2. Thiosulfate Production
2.1.3. Absorbance Spectra of Hydroxybenzene/Benzoquinone Redox Reactions
2.1.4. Hydroxybenzene and Benzoquinone Comproportionation, Semiquinone Formation and Polysulfide Production
2.1.5. Hydroxybenzenes and Benzoquinone as Polysulfide Reductants
2.1.6. Effects of Dihydroxybenzene and p-Benzoquinone on Cellular Sulfur Metabolism
2.2. H2S Oxidation by Catecholamines
2.3. H2S Oxidation by Hydroxybenzophenones
3. Discussion
3.1. Specificity of Hydroxyl Groups and Their Positioning
3.1.1. Dihydroxybenzenes
3.1.2. Trihydroxybenzenes
3.1.3. Catecholamines
3.1.4. Hydroxybenzophenones
3.2. Mechanism of Polysulfide Formation
3.2.1. Polysulfide Production by 1,4-Dihydroxybenzene
3.2.2. Polysulfide Production by 1,4-Benzoquinone
3.3. Mechanism of Thiosulfate Formation
3.4. Extent of H2S Oxidation by 1,4-Dihydroxybenzene, 1,4-Benzoquinone, Pyrogallol and Epinephrine
3.5. Other Possible Cytoprotective Effects
4. Methods
4.1. H2S and Polysulfide Measurements in Buffer
4.2. Polyphenol Absorbance Spectrum
4.3. Thiosulfate Measurement in Buffer
4.4. Cells
4.5. Oxygen Dependency of Quinone Reactions with H2S in Buffer
4.6. Chemicals
4.7. Statistical Analysis
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Olson, K.R.; Gao, Y.; Straub, K.D. Oxidation of Hydrogen Sulfide by Quinones: How Polyphenols Initiate Their Cytoprotective Effects. Int. J. Mol. Sci. 2021, 22, 961. https://doi.org/10.3390/ijms22020961
Olson KR, Gao Y, Straub KD. Oxidation of Hydrogen Sulfide by Quinones: How Polyphenols Initiate Their Cytoprotective Effects. International Journal of Molecular Sciences. 2021; 22(2):961. https://doi.org/10.3390/ijms22020961
Chicago/Turabian StyleOlson, Kenneth R., Yan Gao, and Karl D. Straub. 2021. "Oxidation of Hydrogen Sulfide by Quinones: How Polyphenols Initiate Their Cytoprotective Effects" International Journal of Molecular Sciences 22, no. 2: 961. https://doi.org/10.3390/ijms22020961
APA StyleOlson, K. R., Gao, Y., & Straub, K. D. (2021). Oxidation of Hydrogen Sulfide by Quinones: How Polyphenols Initiate Their Cytoprotective Effects. International Journal of Molecular Sciences, 22(2), 961. https://doi.org/10.3390/ijms22020961