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Updated: Jul 20, 2026
06:18
An In Vivo Estrogen Deficiency Mouse Model for Screening Exogenous Estrogen Treatments of Cardiovascular Dysfunction After Menopause
Published on: August 13, 2019
Circulating bioactive androgens in midlife women
Jiangang Chen1, MaryFran R Sowers, Francisco M Moran
1Center for Health and the Environment, University of California, Davis, California 95616, USA.
The Journal of Clinical Endocrinology and Metabolism
|August 31, 2006
Summary
A new bioassay accurately measures bioactive androgens in women, revealing that calculated free testosterone levels differ from actual bioactive levels. This finding is crucial for understanding menopausal transition and women's health.
Area of Science:
- Endocrinology
- Reproductive Biology
- Women's Health
Background:
- Androgenic steroid hormones impact metabolic and cardiovascular health during menopause.
- Characterizing their biological activity is crucial for women's health risk assessment.
Purpose of the Study:
- To develop and validate a cell-based bioassay for measuring androgen receptor-mediated signal transduction in serum.
- To assess bioactive androgen levels in women during the menopausal transition.
Main Methods:
- Developed a luciferase reporter bioassay using HEK 293 cells stably transfected with human androgen receptor and luciferase genes.
- Measured total testosterone and SHBG in serum samples from 49 women (aged 42-52) using immunoassay.
- Calculated free testosterone and compared it with bioassayed bioactive androgen levels.
Main Results:
- Bioactive androgen levels (mean 1.00 nm) were significantly higher than calculated free testosterone levels (mean 0.0156 nm).
- A positive correlation was observed between bioactive androgens and total testosterone in young women and PCOS patients.
- No correlation was found between bioactive androgens and total testosterone in middle-aged women.
Conclusions:
- The developed androgen receptor bioassay provides valuable insights into total bioactive androgens in midlife women.
- Circulating sex hormone-binding globulin (SHBG) levels significantly influence total circulating bioavailable androgen levels.
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