Al Mamun Bhuyan Abdulla, Sahu Itishri, Cao Hang, Lang Florian
Departments of Cardiology, Cardiovascular Medicine, Düsseldorf, Germany.
Vegetative and Clinical Physiology, Eberhard-Karls-University Tuebingen, Düsseldorf, Germany.
Cell Physiol Biochem. 2018;47(4):1352-1364. doi: 10.1159/000490820. Epub 2018 Jun 19.
BACKGROUND/AIMS: The Hedgehog pathway disrupting drug sonidegib is used in the treatment of basal cell carcinoma. Side effects of sonidegib include anemia, which could result either from impaired erythropoiesis or from loss of erythrocytes e.g. due to suicidal erythrocyte death or eryptosis, which is characterized by cell membrane scrambling with phosphatidylserine translocation to the cell surface and by cell shrinkage. Eryptosis is stimulated by cell stress, including energy depletion, hyperosmotic shock, oxidative stress and excessive increase of cytosolic Ca2+ activity ([Ca2+]i). The present study explored, whether sonidegib exerts an effect on eryptosis.
Human erythrocytes have been treated with energy depletion (glucose withdrawal for 48 hours), hyperosmotic shock (addition of 550 mM sucrose for 6 hours), oxidative stress (addition of 0.3 mM tert-butylhydroperoxide [tBOOH] for 50 min) or Ca2+ ionophore ionomycin (1 µM for 60 min) in absence and presence of sonidegib (2-6 µg/ ml). After treatment flow cytometry was employed to quantify phosphatidylserine exposure at the cell surface from annexin-V-binding, and cell volume from forward scatter. Hemolysis was estimated from the hemoglobin concentration in the supernatant.
In the absence of cell stress exposure to sonidegib did not significantly modify annexin-V-binding or forward scatter, but triggered hemolysis. Energy depletion, hyperosmotic shock, oxidative stress and ionomycin, all markedly and significantly increased the percentage of annexin-V-binding erythrocytes, and decreased the forward scatter. Sonidegib significantly blunted the effect of energy depletion, hyperosmotic shock, and oxidative stress, but not of ionomycin on annexin-V-binding. Sonidegib further significantly blunted the effect of energy depletion, but not of hyperosmotic shock, oxidative stress, and ionomycin on forward scatter.
Sonidegib is a novel inhibitor of erythrocyte cell membrane scrambling following energy depletion, hyperosmotic shock and oxidative stress.
背景/目的：刺猬信号通路干扰药物索尼吉布用于治疗基底细胞癌。索尼吉布的副作用包括贫血，这可能是由于红细胞生成受损或红细胞丢失所致，例如由于自杀性红细胞死亡或红细胞凋亡，其特征是细胞膜磷脂酰丝氨酸易位至细胞表面并伴有细胞皱缩。细胞应激，包括能量耗竭、高渗休克、氧化应激和胞质Ca2+活性（[Ca2+]i）过度升高，可刺激红细胞凋亡。本研究探讨了索尼吉布是否对红细胞凋亡有影响。
在有无索尼吉布（2 - 6μg/ml）的情况下，用人红细胞进行能量耗竭（48小时无糖培养）、高渗休克（添加550 mM蔗糖6小时）、氧化应激（添加0.3 mM叔丁基过氧化氢[tBOOH]50分钟）或Ca2+离子载体离子霉素（1μM 60分钟）处理。处理后，采用流式细胞术通过膜联蛋白V结合来定量细胞表面磷脂酰丝氨酸的暴露情况，并通过前向散射来定量细胞体积。根据上清液中的血红蛋白浓度估算溶血情况。
在无细胞应激的情况下，暴露于索尼吉布不会显著改变膜联蛋白V结合或前向散射，但会引发溶血。能量耗竭、高渗休克、氧化应激和离子霉素均显著增加了膜联蛋白V结合红细胞的百分比，并降低了前向散射。索尼吉布显著减弱了能量耗竭、高渗休克和氧化应激对膜联蛋白V结合的影响，但未减弱离子霉素的影响。索尼吉布还显著减弱了能量耗竭对前向散射的影响，但未减弱高渗休克、氧化应激和离子霉素的影响。
索尼吉布是一种新型的能量耗竭、高渗休克和氧化应激后红细胞细胞膜磷脂酰丝氨酸易位的抑制剂。
