The role of eryptosis in the pathogenesis of renal anemia: Insights from basic research and mathematical modeling
- 1Pontifical Catholic University of Parana, Brazil
- 2Renal Research Institute, United States
- 3Fresenius (Germany), Germany
- 4Arbor Research Collaborative for Health, United States
- 5Icahn School of Medicine at Mount Sinai, United States
Red blood cells (RBC) are the most abundant cells in the blood. Despite powerful defense systems against chemical and mechanical stressors, their life span is limited to about 120 days in healthy humans and further shortened in patients with kidney failure. Changes in the cell membrane potential and cation permeability trigger a cascade of events that lead to exposure of phosphatidylserine on the outer leaflet of the RBC membrane. The translocation of phosphatidylserine is an important step in a process that eventually results in eryptosis, the programmed death of an RBC. The regulation of eryptosis is complex and involves several cellular pathways, such as the regulation of non-selective cation channels. Increased cytosolic calcium concentration results in scramblase and floppase activation, exposing phosphatidylserine on the cell surface, leading to early clearance of RBCs from the circulation by phagocytic cells. While in healthy subjects eryptosis is physiologically meaningful to recycle iron and other RBC constituents, it is augmented under pathological conditions, such as kidney failure. In chronic kidney disease (CKD) patients, the number of eryptotic RBC is significantly increased, resulting in a shortened RBC lifespan that further compounds renal anemia. In CKD patients, uremic toxins, oxidative stress, hypoxemia, and inflammation contribute to the increased eryptosis rate. Eryptosis may have an impact on renal anemia and depending on the degree of shortened RBC life span, the administration of erythropoiesis stimulating agents is often insufficient to attain desired hemoglobin target levels. The goal of this review is to indicate the importance of eryptosis as a process closely related to lifespan reduction, aggravating renal anemia.
Keywords: Kidney failure, Anemia, eryptosis, Erythropoietin, Phosphatidylserine (PS), Calcium, hypoxia, Oxidative Stress
Received: 23 Aug 2020;
Accepted: 16 Oct 2020.
Copyright: © 2020 Ferreira Dias, Grobe, Rogg, Joerg, Pecoits-Filho, Moreno-Amaral and Kotanko. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: MD, PhD. Peter Kotanko, Renal Research Institute, New York, New York, United States, Peter.Kotanko@rriny.com