Targeted Loss of Androgen Receptor Signaling in Murine Granulosa Cells of Preantral and Antral Follicles Causes Female Subfertility1
| Autor: | Kirsty A Walters, Linda J. Middleton, David J. Handelsman, Shai R. Joseph, Charles M. Allan, Rasmani Hazra, Ulla Simanainen, Mark Jimenez |
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| Rok vydání: | 2012 |
| Předmět: | |
| Zdroj: | Biology of Reproduction. 87 |
| ISSN: | 1529-7268 0006-3363 |
| DOI: | 10.1095/biolreprod.112.102012 |
| Popis: | Ovarian granulosa cells display strong androgen receptor (AR) expression, suggesting a functional role for direct AR-mediated actions within developing mammalian follicles. By crossing AR-floxed and anti-Mullerian hormone (AMH)-Cre recombinase mice, we generated granulosa cell-specific androgen receptor knockout mice (GCARKO). Cre expression, assessed by lacZ activity, localized to 70%-100% of granulosa cells in most preantral to antral follicles, allowing for selected evaluation of granulosa cell AR-dependent actions during follicle development. Relative to wild-type (WT) females, GCARKO females were subfertile, producing a 24% reduction in the number of litters (P < 0.05) over 6 mo and an age-dependent decrease in total number of pups born, evident from 6 mo of age (P < 0.05). Follicle dynamics were altered in GCARKO ovaries at 3 mo of age, with a significant reduction in large preantral and small antral follicle numbers compared to WT ovaries (P < 0.05). Global premature follicle depletion was not observed, but increased follicular atresia was evident in GCARKO ovaries at 6 mo of age, with an 81% increase in unhealthy follicles and zona pellucida remnants (P < 0.01). Cumulus cell expansion was decreased (P < 0.01) and oocyte viability was diminished in GCARKO females, with a significant reduction in the percentage of oocytes fertilized after natural mating and, thus, in the rate of progression to the two-cell embryo stage (P < 0.05). In addition, compared with age-matched WT females, 6-mo-old GCARKO females exhibited significantly prolonged estrous cycles (P ≤ 0.05), suggesting altered hypothalamic-pituitary-gonadal feedback signaling. In conclusion, our findings revealed that selective loss of granulosa cell AR actions during preantral and antral stages of development leads to a premature reduction in female fecundity through reduced follicle health and oocyte viability. |
| Databáze: | OpenAIRE |
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