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Updated: Jun 24, 2026
09:15
Induction of Eryptosis in Red Blood Cells Using a Calcium Ionophore
Published on: January 21, 2020
Thymoquinone-induced suicidal erythrocyte death
Syed M Qadri1, Hasan Mahmud, Michael Föller
1Department of Physiology, University of Tübingen, Germany.
Summary
Thymoquinone, a nutrient with anticancer properties, induces suicidal erythrocyte death (eryptosis). This process involves phosphatidylserine exposure and cell shrinkage, similar to apoptosis in nucleated cells.
Area of Science:
- Biochemistry
- Cell Biology
- Hematology
Background:
- Thymoquinone exhibits anticarcinogenic properties by inducing apoptosis in tumor cells.
- Eryptosis, or suicidal erythrocyte death, is characterized by phosphatidylserine exposure and cell shrinkage.
- Eryptosis can be triggered by increased intracellular calcium, ceramide, and protein kinase C.
Purpose of the Study:
- To investigate the effect of thymoquinone on eryptosis.
- To determine if thymoquinone induces suicidal death in erythrocytes.
Main Methods:
- Flow cytometry (FACS) was used to analyze phosphatidylserine exposure (annexin V-binding) and cell shrinkage (forward scatter).
- Immunofluorescence was employed to detect ceramide formation.
- Hemoglobin release was measured to assess hemolysis.
Main Results:
- Thymoquinone significantly increased phosphatidylserine exposure on erythrocytes.
- Thymoquinone induced cell shrinkage in erythrocytes.
- No significant ceramide formation or hemolysis was observed.
- The effect was independent of extracellular calcium but was inhibited by staurosporine.
Conclusions:
- Thymoquinone triggers eryptosis, a form of suicidal erythrocyte death.
- This finding suggests a parallel between thymoquinone's apoptotic effect on tumor cells and its eryptotic effect on erythrocytes.
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