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Archive - Apr 13, 2012

Epigenetic Changes May Underlie Preeclampsia

Virginia Commonwealth University (VCU) School of Medicine researchers have discovered that epigenetic-based changes in the gene expression of a key enzyme may contribute to high blood pressure and increase susceptibility to forming blood clots in pregnant women with preeclampsia. These findings could provide clues to the best treatment approaches for high blood pressure and the formation of blood clots that can block blood flow to a pregnant woman’s internal organs and lead to organ failure. Researchers have been working to determine the root cause of preeclampsia on the molecular level and have now determined that epigenetic mechanisms may be at play. Epigenetics refers to changes in gene expression that are mediated through mechanisms other than changes in the DNA sequence. In a study published online on April 9, 2012 in Hypertension, a journal of the American Heart Association, the VCU team reported that thromboxane synthase – an important inflammatory enzyme – is increased in the blood vessels of expectant mothers with preeclampsia. The thromboxane synthase gene codes for this enzyme, which is involved in several processes, including cardiovascular disease and stroke. This enzyme results in the synthesis of thromboxane, which increases blood pressure and causes blood clots. “The present work is unique because it opens up a new concept as to the cause and subsequent consequences of preeclampsia relating to epigenetics,” said corresponding author Scott W. Walsh, Ph.D., professor in the VCU Department of Obstetrics and Gynecology. “It is the first study to show that epigenetic alterations in the blood vessels of the mother are related to preeclampsia.” According to Dr. Walsh, one of the main epigenetic mechanisms is methylation of the DNA, which controls the expression of genes.

How Worms “Speak” to Each Other

All animals seem to have ways of exchanging information—monkeys vocalize complex messages, ants create scent trails to food, and fireflies light up their bellies to attract mates. Yet, despite the fact that nematodes, or roundworms, are among the most abundant animals on the planet, little is known about the way they network. Now, research led by California Institute of Technology (Caltech) biologists has shown that a wide range of nematodes communicate using a recently discovered class of chemical cues. A paper outlining their studies—which were a collaborative effort with the laboratory of Dr. Frank C. Schroeder, assistant scientist at the Boyce Thompson Institute for Plant Research (BTI) of Cornell University—was published online on April 12, 2012 in the journal Current Biology. Previous research by several members of this team had recently shown that a much-studied nematode, Caenorhabditis elegans, uses certain chemical signals to trade data. What was unknown was whether other worms of the same phylum "talk" to one another in similar ways. But when the researchers looked at a variety of nematodes, they found the very same types of chemicals being combined and used for communication, says Dr. Paul Sternberg, the Thomas Hunt Morgan Professor of Biology at Caltech and senior author on the study. "It really does look like we've stumbled upon the letters or words of a universal nematode language, the syntax of which we don't yet fully understand," he says. Nematodes are wide-ranging creatures; they have been found in hot springs, arctic ice, and deep-sea sediments. Many types of nematodes are harmless, or even beneficial, but others cause damage to plants and harm to humans and animals.