Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Uterine Cells Produce Their Own Estrogen During Pregnancy

21.07.2009
For decades, scientists assumed that the ovary alone produced steroid hormones during pregnancy. In a new study in mice, however, researchers demonstrate that once an embryo attaches to the uterine wall, the uterus itself actually synthesizes the estrogen needed to sustain the pregnancy.

This is the first time that the uterus has been identified as an endocrine organ, said University of Illinois veterinary biosciences professor Indrani Bagchi, who led the study with doctoral student Amrita Das. Their findings appear this week in the Proceedings of the National Academy of Science.

“It’s the local estrogen that’s critical in maintaining the growth of blood vessels within the uterus,” Das said. After an embryo implants, the researchers found, this locally produced estrogen acts in concert with progesterone secreted from the ovaries to spur the differentiation of uterine stromal cells, a process called decidualization, and promotes the growth of blood vessels that support the development of the embryo.

The researchers discovered that during decidualization, mouse uterine stromal cells increase their expression of P450 aromatase, a key enzyme that acts with other enzymes to convert androgens to estrogen.

Even in pregnant mice that have had their ovaries removed, the production of uterine estrogen is able to support the growth and differentiation of the tissue and blood vessels needed to sustain the pregnancy.

Progesterone supplementation is required, however, indicating that local estrogen alone is not sufficient to maintain pregnancy.

Blocking the activity of the aromatase with an inhibitor also blocked decidualization, the researchers found, another indication that a successful pregnancy relies on estrogen production in uterine cells.

There are advantages to producing the appropriate amount of estrogen right where it is needed, rather than relying on the ovaries, Bagchi said.

“During pregnancy, the ovaries would need to secrete a high level of estrogen to ensure that the right amount of estrogen is present in the uterus to support decidualization,” she said. “You can imagine that if the estrogen level goes high systemically, it could have a deleterious effect on pregnancy itself by antagonizing the progesterone action.”

The findings may also be helpful to the study of endometriosis, said molecular and integrative physiology professor Milan Bagchi, an author on the study. This disorder involves the growth of endometrial tissue, which is normally shed during menstruation, at sites outside the uterus, such as the peritoneal cavity and ovaries, producing painful lesions. Endometriosis is spurred, in part, by unusually high levels of estrogen secreted from endometrial tissue growing at these extrauterine sites, he said.

Except during pregnancy, “a normal cycling uterus does not make estrogen,” he said. High estrogen levels block the activity of progesterone and can cause the

non-cancerous growth of tissue seen in endometriosis.

This study was supported by the National Institutes of Health (NIH) and by the Eunice Kennedy Shriver National Institute of Child Health and Human Development at the NIH as part of the Specialized Cooperative Centers Program in Reproduction and Infertility Research.

Diana Yates | University of Illinois
Further information:
http://www.illinois.edu

Further reports about: Bagchi Estrogen Health NIH Uterine blood vessel methanol fuel cells pregnancy

More articles from Life Sciences:

nachricht Seeing on the Quick: New Insights into Active Vision in the Brain
15.08.2018 | Eberhard Karls Universität Tübingen

nachricht New Approach to Treating Chronic Itch
15.08.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Unraveling the nature of 'whistlers' from space in the lab

15.08.2018 | Physics and Astronomy

Diving robots find Antarctic winter seas exhale surprising amounts of carbon dioxide

15.08.2018 | Earth Sciences

Early opaque universe linked to galaxy scarcity

15.08.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>