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Updated: May 23, 2026

An In Vivo Estrogen Deficiency Mouse Model for Screening Exogenous Estrogen Treatments of Cardiovascular Dysfunction After Menopause
Published on: August 13, 2019
Estrogens need insulin-like growth factor I cooperation to exert their neuroprotective effects in post-menopausal
M Giunta1, A E Rigamonti, S M Bonomo
1Department of Medical Biotechnology and Translational Medicine, University of Milan, via Vanvitelli 32, 20129 Milan, Italy. marialuisa.giunta@guest.unimi.it
Background:
The abrupt fall in estrogens levels during the menopausal transition may connote an hormonal state predisposing to neurodegenerative disorders, e.g. Alzheimer's disease (AD). Reportedly, the neurotrophic activity of estrogen involves an interaction with IGF-I.
Aim:
To evaluate the leukocyte gene expression of progesterone receptor (PR-A/B) and interleukin 6 (IL-6), two parameters under the control of estrogens and involved in the pathogenesis of AD.
Subjects:
The study was conducted in non-demented women divided into two groups according to their pre- or post-menopausal state; each group being further divided into two subgroups based on their circulating levels of IGF-I (normal or low). An additional sample of AD-affected women served as a comparison group.
Results:
Estrogens maintained their full activity only when IGF-I levels were in the range of normalcy. On the contrary, if the concentrations of one or both hormones were reduced, estrogens were not anymore capable to control the gene expression of PR-A/B or IL-6.
Conclusions:
Before administering hormone-based replacement therapy, characterization of the somatotropic function should be performed in the early phase of the menopause.
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