Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Substance in urine predicts development of preeclampsia

05.01.2005


A substance found in the urine of pregnant women can be measured to predict the later development of preeclampsia, according to research from the National Institute of Child Health and Human Development of the National Institutes of Health.

"We may have reached a turning point in the extensive federal research investigation of this frequent, life-threatening complication of pregnancy," said Duane Alexander, M.D., Director of the NICHD. "This finding sets the stage for the development of a test to screen women for high risk of preeclampsia. Once these women are identified through such a test, we can target studies to find effective ways to prevent its progression or to keep the most dangerous complications from occurring."

The researchers found women were highly likely to develop preeclampsia if they had low levels of a substance known as placental growth factor (PlGF) in their urine. PlGF works in combination with a substance called vascular endothelial growth factor (VEGF). Together, the two substances foster the growth of new blood vessels, and maintain the health of cells that line the inside of blood vessels, including those in the placenta that support the developing fetus. The researchers believe that the high blood pressure and other symptoms characteristic of preeclampsia result from low levels of PlGF and VEGF.



Researchers are making plans to refine the finding into an accurate clinical test.

The study appears in the January 5 Journal of the American Medical Association. It was conducted by researchers at the NICHD, Harvard University Medical School, the Harvard School of Public Health, Beth Israel Deaconess Medical Center, Allied Technology Group, and the University of Cincinnati College of Medicine. Much of the funding for the study was provided by the NICHD and another of the NIH Institutes, the National Institute of Diabetes and Digestive and Kidney Diseases.

A few women--such as those pregnant with more than one baby or with long-term high blood pressure--are known to be at high risk for preeclampsia, explained the study’s first author, Richard Levine, M.D., M.P.H., of NICHD’s Division of Epidemiology, Statistics, and Prevention Research. However, the vast majority of cases strike without warning, in first-time mothers. Usually, a pregnant woman with preeclampsia develops dangerously high blood pressure and begins excreting protein in the urine. In some cases, the condition may progress to eclampsia, a series of potentially fatal seizures. Although the high blood pressure and seizures can be treated, the only cure for preeclampsia is delivery of the baby. Combined estimates of preeclampsia and other hypertension disorders during pregnancy range from 5.9 to 8 percent of all pregnancies in the United States.

In cases where the condition does not progress to eclampsia, infants born to mothers with preeclampsia may be extremely small for their gestational age or may be born prematurely. These conditions, in turn, place the infants at risk for a variety of other birth complications, among them blindness, cerebral palsy, or mental retardation.

To conduct the study, the researchers analyzed stored urine samples of 120 women who developed preeclampsia and compared them to samples from 118 women who did not develop preeclampsia. The analysis was performed on stored samples collected at three intervals during the women’s pregnancies. The urine samples were collected as part of a separate NICHD study published in 1997, which found that pregnant women could not lower their chances of getting preeclampsia by taking calcium supplements.

In the current study, urinary levels of PlGF were significantly lower for the women who subsequently developed preeclampsia than they were for the 118 women who did not develop the condition. For the women who developed preeclampsia, low levels of PlGF were apparent beginning at the 25th through the 28th week of pregnancy. The differences in P1GF levels grew more pronounced by the 29th through the 36th week of pregnancy.

This study builds upon earlier findings by the last author, S. Ananth Karumanchi, M.D., of the Renal Division at the Beth Israel Deaconess Medical Center and Harvard Medical School in Boston. Dr. Karumanchi and his coworkers had previously discovered that a substance called soluble fms-like tyrosine kinase 1 (sFlt-1) circulates in large quantities in the bloodstreams of women with preeclampsia and that sFlt-1 injected into the bloodstream of pregnant rats caused a preeclampsia-like illness.

Last year, Drs. Levine, Karumanchi and their coworkers reported that high levels of sFlt-1 likely influenced the development of preeclampsia, by binding to PlGF and VEGF. Because they were bound to sFlt-1, the two substances could not be used by the blood vessel cells that required them. A release describing that study is available at http://www.nichd.nih.gov/new/releases/preeclampsia.cfm.

Dr. Levine noted that a screening test for PlGF would probably need to be used in conjunction with other measures. He explained that a few of the 118 women who did not develop preeclampsia also had low levels of PlGF. To confirm that preeclampsia is present, women with low levels of PlGF could be referred for a blood test to measure their blood levels of sFlt-1.

A urinary test for PlGF could probably be performed less expensively than could a blood test for sFlt-1, because it wouldn’t require the services of a medical professional to draw blood. Moreover, a urine sample could conceivably be collected at home, and then brought into a medical lab for testing. This would be an advantage over a blood test, especially in countries lacking trained medical staff to draw blood.

Currently, Dr. Levine is planning an additional study to more accurately predict the development of preeclampsia by measuring urinary levels of PlGF. The current study obtained urine samples from pregnant women only on 3 occasions during their pregnancies. In the planned study, researchers would measure urinary PlGF levels throughout pregnancy, in an effort to pinpoint precisely when levels of PlGF begin to drop. Similarly, another study is measuring urinary PlGF levels in a much larger number of women, to gain a better understanding of individual variations in PlGF levels.

Dr. Levine estimates that, pending the results of these studies, a urine test to screen for preeclampsia could be available in 4 to 5 years.

He added that it also might be possible to develop a treatment for preeclampsia, by supplying at risk women with additional PlGF and VEGF. Theoretically, these substances would bind to sFlt-1, allowing the PlGF and VEGF made by the body to be used by the blood vessel cells that require them.

Bob Bock | EurekAlert!
Further information:
http://www.nih.gov

More articles from Health and Medicine:

nachricht Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University

nachricht Direct conversion of non-neuronal cells into nerve cells
03.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Microscopic trampoline may help create networks of quantum computers

17.07.2018 | Information Technology

In borophene, boundaries are no barrier

17.07.2018 | Materials Sciences

The role of Sodium for the Enhancement of Solar Cells

17.07.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>