Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Prenatal Genistein In Soy Reduces Obesity In Offspring

29.03.2006
A single nutrient found in soy products elicits changes in gene behavior that permanently reduce an embryo’s risk of becoming obese later in life, according to an animal study at Duke University Medical Center.

The findings, yet to be confirmed in humans, could explain why Asians have lower rates of obesity and cancer, said the Duke researchers. Asians consume large amounts of soy, which has been linked to lower rates of breast, endometrial and prostate cancer, among other health benefits.

In the Duke study, pregnant Agouti mice that ate a diet rich in genistein, an active ingredient in soy, gave birth to pups that stayed slimmer as adults. Mice that did not receive genistein in utero were much heavier as adults – double the weight of their genistein-fed counterparts. Prenatal genistein also shifted the offspring’s coat color from yellow to brown, demonstrating that a single nutrient can have a widespread systemic impact, said the researchers.

Genistein’s effect occurred early in pregnancy, the equivalent of eight gestational days in humans. The Duke scientists said their results lend support to the "developmental origins of adult disease" hypothesis, in which an individual’s long-term health is influenced by prenatal factors.

Results of the study, funded by the National Institute of Environmental Health Sciences and the National Cancer Institute, are published in the April 1, 2006, issue of the journal Environmental Health Perspectives.

"We are increasingly finding that our parent’s and even our grandparent’s nutritional status and environmental exposures can regulate our future risk of disease," said Randy Jirtle, Ph.D., professor of radiation oncology and senior author of the study. "In other words, it may not only be the hamburgers and fries we are eating, but also what our parents consumed or encountered in the environment that predisposes us to various conditions."

Jirtle said a mechanism called DNA "methylation" is increasingly identified as the trigger for environmentally-caused gene alterations. During this process, a person’s exposure to chemicals, nutrients, or even a behavioral experience such as nurturing can elicit a change in how a specific gene behaves – but without altering the genetic sequence in any way.

Rather, the exposure or event prompts a quartet of atoms or "methyl group" to attach to the regulatory region of a gene, where it acts as a switch to activate or silence the gene. Such an effect is called "epigenetic" because it occurs over and above the gene sequence without altering any of the letters of the gene’s four-unit code, said Jirtle. Micronutrients can change the extent of DNA methylation by directly donating methyl groups or by altering the efficiency by which DNA methylation is modified, said Jirtle.

In the current study, maternal dietary genistein caused a single mouse gene called "agouti" to become methylated at six specific sites near its regulatory region, thereby reducing the gene’s expression. The agouti methylation consistently occurred throughout several germ layers of embryonic tissue, indicating that genistein acted during early embryonic development. Moreover, the methylation changes persisted into adulthood, providing the first evidence that in utero dietary genistein alters epigenetic gene regulation, coat color, and susceptibility to adult obesity in animals.

The agouti gene is not epigentically regulated in humans as it is in the Agouti mouse, said Jirtle. But soy’s potential benefits could exert themselves through other human genes whose expression is altered by DNA methylation, he said.

"Methylation is a common event in the human genome, and it is a highly malleable effect that occurs during rapid periods of development, but it can also occur in childhood and even in adulthood," he said.

Because many infants receive soy milk, the impact of genistein in humans should be carefully assessed, he said. Pregnant women are exposed to hundreds of compounds in foods, prenatal vitamins and the environment that could potentially methylate susceptible genes, he said. The effects of each compound could be beneficial or detrimental, depending upon the timing of exposure, the dose and the tissue exposed, said Jirtle.

"Our study demonstrates there are highly sensitive windows early in development when environmental exposures can permanently alter the offspring’s adult susceptibility to disease," said Jirtle. "Therefore, we need to examine the effect of environmental exposures during pregnancy, not just in adulthood, if we want to accurately assess their risk or benefit to humans."

His earlier research demonstrated that four common nutritional supplements fed to pregnant mice, including folic acid and vitamin B12, lowered their offspring’s susceptibility to obesity, diabetes and cancer by methylating the same agouti gene. Yet how nutrients interact in combination or in extremely high doses remains unclear, he said.

"There could be additive or synergistic effects between folic acid and genistein, or any such compounds, that hypermethylate certain genes," said Dana Dolinoy, MPH, lead author of the study. "What is good in small amounts could be harmful in large amounts. We simply don’t know the effects of literally hundreds of compounds that we intentionally or inadvertently ingest or encounter each day."

Of related concern, soy is a staple of almost all laboratory mouse diets. Soy could inadvertently methylate select genes and thus mask the deleterious effects of various chemicals being tested for their risk in humans, she said.

"In the future, we may be able to potentially select compounds to protect a person from being predisposed to developing a variety of conditions," said Jirtle. "There is a vast, unknown potential for studying how our environment interacts with our epigenome to determine how we developed and who we will become."

Becky Levine | EurekAlert!
Further information:
http://www.mc.duke.edu

More articles from Agricultural and Forestry Science:

nachricht Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli
26.04.2017 | University of the Basque Country

nachricht New data unearths pesticide peril in beehives
21.04.2017 | Cornell University

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

SwRI-led team discovers lull in Mars' giant impact history

26.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>