Navigation Links
Study finds how BPA affects gene expression, anxiety; Soy mitigates effects

New research led by researchers at North Carolina State University shows that exposure to the chemical bisphenol A (BPA) early in life results in high levels of anxiety by causing significant gene expression changes in a specific region of the brain called the amygdala. The researchers also found that a soy-rich diet can mitigate these effects.

"We knew that BPA could cause anxiety in a variety of species, and wanted to begin to understand why and how that happens," says Dr. Heather Patisaul, an associate professor of biology at NC State and lead author of a paper describing the work. BPA is a chemical used in a wide variety of polycarbonate plastics and epoxy resins, and is used in consumer products such as some food containers.

In the study, rats were exposed to low doses of BPA during gestation, lactation (nursing) and through puberty. One group of animals was fed only soy; one group was fed a soy-free diet; one group was fed only soy and exposed to BPA; and one group was fed no soy and exposed to BPA. Blood tests showed that the animals exposed to BPA had BPA levels well within the range found in humans. Similarly, blood tests of animals fed soy showed levels of genistein, an estrogen-like chemical found in soy, were at levels within the human range for vegetarians and others who regularly consume soy foods.

Among adolescent rats on the soy-free diet, both males and females that had been exposed to BPA exhibited significantly higher levels of anxiety. The researchers also found, for the first time, gene changes within the brain associated with this elevated anxiety.

Specifically, the study reveals that gene expression changes in the amygdala, a brain region known to play a role in mediating responses to fear and stress, are associated with the behavioral changes. Two of the affected genes were estrogen receptor beta and the melanocortin receptor 4. Both are required for oxytocin release, thus changes in oxytocin/vasopressin signaling pathways may underpin the behavioral changes. Oxytocin is a hormone and neurotransmitter that has been linked to social behavior.

However, the researchers also found that adolescent rats on the soy-rich diet did not exhibit anxiety suggesting that the soy-rich diet may mitigate the effects of BPA. But a soy-rich diet raises questions of its own.

"Soy contains phytoestrogens that can also affect the endocrine system, which regulates hormones," Patisaul says. "It is not clear whether these phytoestrogens are what mitigate the effect of BPA, or if it is something else entirely. That's a question we're hoping to address in future research."


Contact: Matt Shipman
North Carolina State University

Related biology news :

1. Study by UC Santa Barbara researchers suggests that bacteria communicate by touch
2. Law that regulates shark fishery is too liberal: UBC study
3. New study will help protect vulnerable birds from impacts of climate change
4. Study jointly led by UCSB researcher supports theory of extraterrestrial impact
5. BYU study: Using a gun in bear encounters doesnt make you safer
6. 15-year study: When it comes to creating wetlands, Mother Nature is in charge
7. Pycnogenol (French maritime pine bark extract) shown to improve menopause symptoms in new study
8. Crystal structure of archael chromatin clarified in new study
9. EU-funded study underlines importance of Congo Basin for global climate and biodiversity
10. University of Houston study shows BP oil spill hurt marshes, but recovery possible
11. Study demonstrates cells can acquire new functions through transcriptional regulatory network
Post Your Comments:
(Date:10/29/2015)... 2015 NXTD ) ("NXT-ID" ... on the growing mobile commerce market and creator ... a leading marketplace to discover and buy innovative ... wallet on StackSocial for this holiday season.   ... "Company"), a biometric authentication company focused on the ...
(Date:10/26/2015)... , October 26, 2015 ... --> adds Biometrics Market ... 2021 as well as Emerging Biometrics ... reports to its collection of IT ... . --> ...
(Date:10/22/2015)... (NASDAQ: AWRE ), a leading supplier of biometrics software and ... 30, 2015.  --> --> ... decrease of 33% compared to $6.0 million in the same quarter ... $2.2 million, or $0.10 per diluted share, which compared to $2.6 ... year ago.  --> --> ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... and NEW YORK , November 24, 2015 ... by Bristol-Myers Squibb in a European ... Squibb Company in which the companies will work closely ... and other areas of unmet medical need. The collaboration is ... 5, the latest LSP fund. This is the first investment ...
(Date:11/24/2015)... NEW YORK , Nov. 24, 2015 According ... today than in 2005. This is something that many doctors, ... long time. One questions remains: with fewer PSA tests being ... cancer ? Dr. David Samadi, "Despite ... cancer, the disease remains the second leading cancer cause of ...
(Date:11/23/2015)...   Ceres, Inc . (Nasdaq: CERE ), ... the fiscal year ended August 31, 2015 and provided ... --> During fiscal year 2015, Ceres ... with a better balance of yield, energy and nutrition. ... several leading crop input providers and made significant progress ...
(Date:11/23/2015)... ... 2015 , ... Shimadzu Corporation announces that it has won ... system. The award from R&D magazine recognizes Shimadzu’s Nexera UC system as one ... analytical and testing category. R&D Magazine chose the Nexera UC system because its ...
Breaking Biology Technology: