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Reverse Yeast Two-hybrid System to Identify Mammalian Nuclear Receptor Residues that Interact with Ligands and/or Antagonists
Published on: November 15, 2013
Mechanisms of sex steroids. Future developments
1Center of Obstetrics and Gynecology, University Hospital of Frankfurt, Theodor-Stern-Kai 7, D-60590 Frankfurt am Main, Germany.
Maturitas
|April 6, 2004
Summary
Selective estrogen receptor modulators (SERMs) and selective progesterone receptor modulators (SPRMs) offer alternatives in hormone therapy. Progestogens in hormone replacement therapy (HRT) require careful selection to minimize risks like breast cancer and cardiovascular disease.
Area of Science:
- Endocrinology
- Pharmacology
- Oncology
Background:
- Hormone replacement therapy (HRT) with estrogens is standard for estrogen deficiency symptoms.
- Progestogens, used for endometrial protection during HRT, significantly influence breast cancer and cardiovascular disease risks.
- Current risk assessment tools are insufficient for selecting safer progestogens.
Purpose of the Study:
- To explore alternative therapies like selective estrogen receptor modulators (SERMs) and selective progesterone receptor modulators (SPRMs).
- To highlight the critical role of progestogen selection in HRT to mitigate adverse effects.
- To emphasize the need for standardized tests to evaluate the safety of estrogen-progestogen preparations.
Main Methods:
- Review of experimental, clinical, and epidemiological data on hormone therapy risks.
- Discussion of the proliferative effects of estrogens and progestogens on breast tissue.
- Consideration of glucocorticoid activity of progestogens in cardiovascular disease development.
Main Results:
- Estrogen-progestogen combinations may increase breast cancer risk due to enhanced proliferation.
- Glucocorticoid activity, not androgenic activity, of progestogens is linked to cardiovascular disease.
- Progestogens with glucocorticoid effects might promote atherosclerosis via thrombin receptor upregulation.
Conclusions:
- SERMs and SPRMs show promise but cannot fully replace estrogens for deficiency.
- Development of in vivo tests is crucial for assessing proliferative and atherogenic potentials of HRT preparations.
- Careful selection of progestogens with minimal glucocorticoid activity is essential for safer HRT.
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