Original ArticleInhibition of Suicidal Erythrocyte Death by ProbucolShaik, Nazneen PhD; Lupescu, Adrian MD; Lang, Florian MDAuthor Information Department of Physiology, University of Tuebingen, Tuebingen, Germany. Reprints: Florian Lang, MD, Physiologisches Institut, der Universität Tübingen, Gmelinstraße 5, D-72076 Tübingen, Germany (e-mail: firstname.lastname@example.org). Support by the Deutsche Forschungsgemeinschaft. The authors declare that they have no conflicts to disclose. N. Shaik and A. Lupescu have contributed equally. Received July 03, 2012 Accepted October 16, 2012 Journal of Cardiovascular Pharmacology: February 2013 - Volume 61 - Issue 2 - p 120-126 doi: 10.1097/FJC.0b013e3182798abc Buy Metrics Abstract Abstract: Probucol, an antioxidant and anti-inflammatory agent counteracting atherosclerosis and restenosis, is partially effective by influencing suicidal cell death or apoptosis. In analogy to apoptosis of nucleated cells, suicidal death of erythrocytes or eryptosis is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine exposure at the erythrocyte surface. Eryptosis is stimulated by increase in cytosolic Ca2+ activity, for example, after energy depletion or oxidative stress. The present study explored whether probucol influences eryptosis. Phosphatidylserine exposure was estimated from annexin-V-binding, cell volume from forward scatter (FSC), and cytosolic Ca2+ concentration from fluo-3 fluorescence in flow cytometry. As a result, energy depletion (48-hour glucose removal) increased annexin-V-binding, decreased FSC, and increased fluo-3 fluorescence. Probucol (≤30 μM) did not significantly modify annexin-V-binding, FSC, or fluo-3 fluorescence in the presence of glucose but (at ≥5 μM) blunted the effect of glucose depletion on annexin-V-binding. Probucol (≥20 μM) only slightly blunted the effects of glucose depletion on FSC and fluo-3 fluorescence. Ca2+ ionophore ionomycin (1 μM) and oxidative stress (30-minute exposure to 0.3 mM of tert-butylhydroperoxide) increased annexin-V-binding, effects again blunted by 30 μM of probucol. In conclusion, probucol blunts cell membrane scrambling after energy depletion and oxidative stress, effects primarily because of interference with the scrambling effects of increased cytosolic Ca2+ concentration. © 2013 Lippincott Williams & Wilkins, Inc.