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Updated: Jul 9, 2026
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Use of LysoTracker to Detect Programmed Cell Death in Embryos and Differentiating Embryonic Stem Cells
Published on: October 11, 2012
Cell death in fetal oocytes: many players for multiple pathways.
Massimo De Felici1, Anna Maria Lobascio, Francesca Gioia Klinger
1Department of Public Health and Cell Biology, Section of Histology and Embryology, University of Rome Tor Vergata, Rome, Italy. defelici@uniroma2.it
Autophagy
|December 21, 2007
Summary
Fetal oocytes undergo programmed cell death (PCD) through various pathways, including apoptosis, autophagy, and necrosis. Caspase inhibitors only partially block oocyte death, indicating complex cell death mechanisms.
Area of Science:
- Reproductive Biology
- Cell Biology
- Developmental Biology
Background:
- Programmed cell death (PCD) is crucial for development.
- Fetal oocyte development involves complex cellular processes.
- Understanding oocyte PCD is vital for reproductive health.
Purpose of the Study:
- To investigate novel characteristics of fetal oocyte programmed cell death (PCD).
- To identify new aspects of oocyte PCD using a short-term culture system.
- To explore the interplay of different cell death pathways in fetal oocytes.
Main Methods:
- Short-term culture of mouse fetal oocytes.
- TUNEL staining, DNA laddering, Annexin V binding, PARP cleavage assays.
- Transmission electron microscopy (TEM) and fluorescence microscopy.
- Inhibition studies using caspase, calpain, and mTOR inhibitors.
Main Results:
- Fetal oocytes undergo apoptotic degeneration, but also display atypical apoptotic, autophagic, and necrotic morphologies.
- A subpopulation of TUNEL-positive oocytes showed no detectable caspase activity.
- Caspase inhibitors slowed but did not abolish oocyte death.
- Calpain inhibition reduced oocyte death, while mTOR inhibition increased it.
- Expression of apoptosis-inducing factor and Beclin 1 was observed.
Conclusions:
- Fetal oocytes possess and can activate multiple cell death pathways, including caspase-dependent and independent apoptosis, autophagy, and necrosis.
- Oocyte cell death involves complex interactions between various pathways.
- Further research is needed to clarify causal correlations and in vivo/in vitro stimuli for these pathways.
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