Bibliographic Details
| Title: |
Measuring the rate of NADPH consumption by glutathione reductase in the cytosol and mitochondria. |
| Authors: |
Ting, Kenneth K. Y.1,2 (AUTHOR), Floro, Eric2,3 (AUTHOR), Dow, Riley1,2 (AUTHOR), Jongstra-Bilen, Jenny1,2,4 (AUTHOR), Cybulsky, Myron I.1,2,4,5 (AUTHOR) myron.cybulsky@utoronto.ca, Rocheleau, Jonathan V.2,3,6,7 (AUTHOR) jon.rocheleau@utoronto.ca |
| Source: |
PLoS ONE. 12/5/2024, Vol. 19 Issue 12, p1-15. 15p. |
| Subject Terms: |
*GLUCOSE-6-phosphate dehydrogenase, *GLUTATHIONE reductase, *MEMBRANE transport proteins, *MYELOID cells, *NICOTINAMIDE adenine dinucleotide phosphate |
| Abstract: |
Background: NADPH is an essential co-factor supporting the function of enzymes that participate in both inflammatory and anti-inflammatory pathways in myeloid cells, particularly macrophages. Although individual NADPH-dependent pathways are well characterized, how these opposing pathways are co-regulated to orchestrate an optimized inflammatory response is not well understood. To investigate this, techniques to track the consumption of NADPH need to be applied. Deuterium tracing of NADPH remains the gold standard in the field, yet this setup of mass-spectrometry is technically challenging and not readily available to most research groups. Furthermore, NADPH pools are compartmentalized in various organelles with no known membrane transporters, suggesting that NADPH-dependent pathways are regulated in an organelle-specific manner. Conventional methods such as commercial kits are limited to quantifying NADPH in whole cells and not at the resolution of specific organelles. These limitations reflect the need for a novel assay that can readily measure the consumption rate of NADPH in different organelles. Methods: We devised an assay that measures the consumption rate of NADPH by glutathione-disulfide reductase (GSR) in the mitochondria and the cytosol of RAW264.7 macrophage cell lines. RAW264.7 cells were transfected with Apollo-NADP+ sensors targeted to the mitochondria or the cytosol, followed by the treatment of 2-deoxyglucose and diamide. Intravital imaging over time then determined GSR-dependent NADPH consumption in an organelle-specific manner. Discussion: In lipopolysaccharide (LPS)-stimulated RAW264.7 cells, cytosolic and mitochondrial NADPH was consumed by GSR in a time-dependent manner. This finding was cross validated with a commercially available NADPH kit that detects NADPH in whole cells. Loading of RAW264.7 cells with oxidized low-density lipoprotein followed by LPS stimulation elevated GSR expression, and this correlated with a more rapid drop in cytosolic and mitochondrial NADPH in our assay. The current limitation of our assay is applicability to transfectable cell lines, and higher expression of plasmid-encoded sensors relative to endogenous glucose-6-phosphate dehydrogenase. [ABSTRACT FROM AUTHOR] |
|
Copyright of PLoS ONE is the property of Public Library of Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) |
| Database: |
Academic Search Complete |
|
Full text is not displayed to guests. |
Login for full access.
|
