Sara Soares Tozoni1, Gabriela Ferreira Dias1, Gabriela Bohnen1, Nadja Grobe2, Roberto Pecoits-Filho1, Peter Kotanko2,3, Andréa Novais Moreno-Amaral4.
Abstract
BACKGROUND/AIMS: Red blood cell (RBC) death could contribute to anemia in chronic kidney disease (CKD) patients. Recent observational research has suggested a relationship between RBC death (eryptosis) and hypoxemia in hemodialysis patients. Thus, we studied the isolated and joint effects of a uremic toxin (indoxyl sulfate; IS) and hypoxia on RBC biology.
METHODS: We incubated RBC from healthy donors with IS at concentrations of 0.01mM, 0.09mM and 0.17mM under both normoxic (21% O2) and hypoxic (5% O2) conditions for 24 hours. Eryptosis was evaluated by RBC phosphatidylserine (PS) exposure, cell volume, and cytosolic calcium which were quantified by Annexin-V+, forward scatter, and Fluo-3AM+ binding, respectively. RBC redox balance was reported by reactive oxygen species (ROS) production and intracellular reduced glutathione (GSH). Analyses were performed by flow cytometry.
RESULTS: Hypoxia induced a 2-fold ROS production compared to normoxia. PS exposure and cytosolic calcium increased, while cell volume decreased by hypoxia and likewise by IS. IS increased ROS production in a dose-dependent manner under conditions of both normoxia and hypoxia. The same conditions promoted a GSH decrease with IS intensifying the hypoxia-induced effects.
CONCLUSION: In summary, our results indicate that the concurrent presence of hypoxia and uremia augments RBC death and may therefore, contribute to the genesis of anemia in CKD. © Copyright by the Author(s). Published by Cell Physiol Biochem Press.
BACKGROUND/AIMS: Red blood cell (RBC) death could contribute to anemia in chronic kidney disease (CKD) patients. Recent observational research has suggested a relationship between RBC death (eryptosis) and hypoxemia in hemodialysis patients. Thus, we studied the isolated and joint effects of a uremic toxin (indoxyl sulfate; IS) and hypoxia on RBC biology.
METHODS: We incubated RBC from healthy donors with IS at concentrations of 0.01mM, 0.09mM and 0.17mM under both normoxic (21% O2) and hypoxic (5% O2) conditions for 24 hours. Eryptosis was evaluated by RBC phosphatidylserine (PS) exposure, cell volume, and cytosolic calcium which were quantified by Annexin-V+, forward scatter, and Fluo-3AM+ binding, respectively. RBC redox balance was reported by reactive oxygen species (ROS) production and intracellular reduced glutathione (GSH). Analyses were performed by flow cytometry.
RESULTS: Hypoxia induced a 2-fold ROS production compared to normoxia. PS exposure and cytosolic calcium increased, while cell volume decreased by hypoxia and likewise by IS. IS increased ROS production in a dose-dependent manner under conditions of both normoxia and hypoxia. The same conditions promoted a GSH decrease with IS intensifying the hypoxia-induced effects.
CONCLUSION: In summary, our results indicate that the concurrent presence of hypoxia and uremia augments RBC death and may therefore, contribute to the genesis of anemia in CKD. © Copyright by the Author(s). Published by Cell Physiol Biochem Press.
Entities:
Keywords:
Indoxyl sulfate; Eryptosis; Hypoxia; ROS; Glutathione; Uremia
Mesh：
Substances：
Year: 2019
PMID： 31661199 DOI： 10.33594/000000173
Source DB: PubMed Journal: Cell Physiol Biochem ISSN： 1015-8987