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Published on: October 16, 2020

Prepubertal primordial follicle loss in mice is not due to classical apoptotic pathways

Candace M Tingen1, Sarah K Bristol-Gould, Sarah E Kiesewetter

  • 1Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.

Biology of Reproduction
|March 7, 2009
PubMed

Insights

Most primordial follicles in mice are lost before puberty. This study found that this loss is not due to apoptosis (programmed cell death) but rather a nonapoptotic pathway, suggesting a different mechanism for follicle elimination.

Area of Science:

  • Reproductive Biology
  • Developmental Biology
  • Cell Biology

Background:

  • Ovarian follicle development is crucial for female reproduction.
  • A significant loss of primordial follicles occurs during ovarian development in mice.
  • Apoptosis (programmed cell death) is a known mechanism for cell elimination.

Purpose of the Study:

  • To investigate if apoptosis is the primary mechanism responsible for the elimination of primordial follicles during the prepubertal period in mice.
  • To examine follicular atresia and identify the cell death pathway involved in primordial follicle loss.

Main Methods:

  • Analysis of prepubertal mouse ovaries.
  • Measurement of four hallmarks of classical apoptosis in primordial follicles: nuclear condensation, cell shrinkage, caspase 3 activation, poly(ADP-ribose) polymerase 1 (PARP1) cleavage, and DNA fragmentation.

Main Results:

  • The primordial follicle cohort did not exhibit characteristics of classical apoptosis.
  • No significant association was found between primordial follicle loss and nuclear condensation, cell shrinkage, caspase 3 activation, PARP1 cleavage, or DNA fragmentation.

Conclusions:

  • The elimination of primordial follicles during the prepubertal period in mice is not mediated by apoptosis.
  • A nonapoptotic pathway is likely responsible for the significant loss of small follicles in the ovary.
  • Further research is needed to elucidate the specific nonapoptotic mechanisms driving primordial follicle death.

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