This is the first study to detail the mechanism by which the steroid hormone estrogen spurs cell differentiation and blood-vessel growth in the uterus during pregnancy, the researchers report.
The findings, from researchers at the University of Illinois, Emory University, Baylor College of Medicine and New York University, appear in the journal Development.
Connexin 43 (Cx43) belongs to a family of proteins that form junctions between cells that regulate the flow of ions and small signaling molecules from cell to cell. At the time of embryo implantation, this gap junction protein is essential to the rapid growth of new blood vessels needed to support the development of the embryo and allow it to implant in the uterine wall, the researchers discovered.
The researchers chose to study Cx43 after analyzing genes that are activated in the presence of estrogen in uterine cells. They found that Cx43 was prominent among the genes whose expression was increased in cells after exposure to estrogen.
University of Illinois veterinary biosciences doctoral student Mary Laws studied the role of Cx43 in pregnant mice and in human endometrial cells. By deleting the Cx43 gene in the uterus immediately after pregnancy in mice, a technique developed by researchers at Baylor, Laws was able to reliably prevent implantation of the embryo in the uterus.
In human endometrial cells (provided by co-author Robert Taylor of Emory University), Cx43 enhanced the differentiation of cells that make up the stromal tissue of the uterus. These cells produce factors that promote the growth of new blood vessels.
One of the factors secreted by the endometrial cells, vascular endothelial growth factor (VEGF), is essential to angiogenesis. In the absence of Cx43, Laws found, the cells failed to differentiate or to produce enough VEGF to spur blood vessel growth.
“The formation of these new blood vessels is extremely critical for embryonic growth at this stage of pregnancy, when the embryo has begun to invade into the uterine tissue, but has yet to make a connection to the placenta where it ultimately gets its nutrients,” said Illinois veterinary biosciences professor Indrani Bagchi, corresponding author on the study. “I think this is the first animal model that shows that disruption of one particular molecule or gene leads to a defect in uterine angiogenesis.”
The findings have important implications for early pregnancy loss and female infertility, she said.
“A fundamental aspect of female reproductive biology is how these hormones signal in uterine tissue in order to support the pregnancy,” said molecular and integrative physiology professor Milan Bagchi, an author on the study. “One of our major goals is to identify the genes that are regulated by estrogen and progesterone precisely at the time when the embryo implants in the uterine wall.”
“Connexin 43 has been shown to be in the uterus in many animal systems – cows and pigs and rodents and humans,” Laws said. “But this is the first time that it’s been shown to be critical for pregnancy.”
This research was sponsored by the recently established Center for Research in Reproduction and Infertility, which is funded by the National Institute of Child Health and Human Development.
Based at the U. of I., the center also draws expertise from Emory University Medical School and Baylor College of Medicine.Editor’s note: To reach Indrani Bagchi, call 217-333-7986; e-mail: firstname.lastname@example.org.
Diana Yates | University of Illinois
Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München
Second research flight into zero gravity
21.10.2016 | Universität Zürich
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences