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Orthotopic Ovarian Transplantation Procedures to Investigate the Life- and Health-span Influence of Ovarian Senescence in Female Mice
Published on: February 12, 2018
Ovarian aging in squirrel monkeys (Saimiri sciureus)
Margaret L Walker1, Daniel C Anderson, James G Herndon
1Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329, USA. mlwalke@emory.edu
Reproduction (Cambridge, England)
|August 7, 2009
Summary
Female squirrel monkeys experience ovarian follicle depletion with age. Unusual granulosa cell clusters appear in older monkeys, potentially influencing reproductive lifespan and offering insights into human granulosa cell tumors.
Area of Science:
- Reproductive biology
- Comparative anatomy
- Gerontology
Background:
- Female squirrel monkeys (Saimiri sciureus) have a reproductive period from 2.5 years to mid-teens.
- Ovarian aging involves complex cytological changes impacting fertility.
- Understanding primate ovarian senescence is crucial for reproductive health research.
Purpose of the Study:
- To investigate age-associated ovarian cytological changes in female squirrel monkeys.
- To characterize the prevalence and nature of ovarian structures in aging monkeys.
- To explore potential links between ovarian aging and reproductive potential.
Main Methods:
- Histological examination of ovaries from 24 squirrel monkeys aged from newborn to 20 years.
- Quantification of primordial follicles and assessment of granulosa cell clusters (GCCs).
- Immunohistochemical analysis for anti-Müllerian hormone expression in GCCs.
Main Results:
- A significant age-related decline in primordial follicle numbers was observed, most pronounced between birth and 5 years.
- Few primordial follicles remained after 8 years of age.
- Abundant, encapsulated granulosa cell clusters (GCCs), expressing anti-Müllerian hormone, emerged in older monkeys (post-8 years) and were histologically similar to human granulosa cell tumors but lacked malignancy.
Conclusions:
- Reproductive senescence in female squirrel monkeys is characterized by progressive ovarian follicle depletion.
- The consistent presence of differentiated GCCs in older, reproductively active monkeys suggests a role in modulating later reproductive potential.
- Studying GCCs in squirrel monkeys may provide valuable insights into the pathophysiology of human granulosa cell tumors.
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