(Press-News.org) WASHINGTON--Low doses of propylparaben--an estrogen-like chemical used as a preservative in personal care products and foods--can alter pregnancy-related changes in the breast in ways that may reduce the normal protection against breast cancer that pregnancy hormones convey, according to a new study being published in the Endocrine Society's journal Endocrinology.
These results, from an animal study that also will be presented at ENDO 2021, the Endocrine Society's annual meeting, lend evidence that propylparaben is an endocrine-disrupting chemical, the researchers say.
An endocrine-disrupting chemical interferes with the actions of hormones in the body. These chemicals can affect hormone-sensitive organs such as the mammary gland, the milk-producing duct in the breast, said the study's senior author Laura N. Vandenberg of the University of Massachusetts in Amherst, Mass.
"We found that propylparaben disrupts the mammary gland of mice at exposure levels that have previously been considered safe based on results from industry-sponsored studies. We also saw effects of propylparaben after doses many times lower, which are more reflective of human intake," Vandenberg said. "Although our study did not evaluate breast cancer risk, these changes in the mammary tissue are involved in mitigating cancer risk in women."
Hormones produced during pregnancy are not only responsible for reorganizing the breast tissue, allowing it to produce milk for the infant. They also are partly responsible for the reduced risk of breast cancer seen in women who give birth at a younger age.
The researchers tested whether propylparaben exposure during the vulnerable period of pregnancy and breastfeeding adversely alters this mammary gland reorganization. They exposed female mice to environmentally relevant doses of this common preservative during pregnancy and breastfeeding. Five weeks after the chemical exposure ended, they examined the mothers' mammary glands.
Compared with pregnant mice that had not received propylparaben, the exposed mice had mammary gland changes not typical of pregnancy, the researchers reported. These mice had increased rates of cell proliferation, which Vandenberg said is a possible risk factor for breast cancer. Additionally, they had less dense epithelial structures, fewer immune cell types and thinner periductal collagen, the connective tissue in the mammary gland.
"Some of these changes may be consistent with a loss of the protective effects that are typically associated with pregnancy," said co-first author, Joshua Mogus, M.S., a Ph.D. student at the University of Massachusetts.
He said future studies should address whether pregnant females exposed to propylparaben are actually more susceptible to breast cancer.
"Because pregnant women are exposed to propylparaben in many personal care products and foods, it is possible that they are at risk," Mogus said.
Pregnant and breastfeeding women should try to avoid using products containing propylparaben and other parabens, he suggested.
"This chemical is so widely used, it may be impossible to avoid entirely," Mogus added. "It is critical that relevant public health agencies address endocrine-disrupting chemicals as a matter of policy."
This research received funding from the University of Massachusetts Commonwealth Honors College Grant, the Endocrine Society's Summer Research Fellowship, and the National Institutes of Health.
Other authors of the study include: Charlotte D. LaPlante, Ruby Bansal, Klara Matouskova, Shannon J. Silva, Elizabeth Daniele, Mary J. Hagen and Karen A. Dunphy of the University of Massachusetts, Benjamin R. Schneider and Sallie S. Schneider of Baystate Medical Center in Springfield, Mass.; and D. Joseph Jerry of the University of Massachusetts and Pioneer Valley Life Sciences Institute in Springfield, Mass.
The manuscript, "Exposure to Propylparaben During Pregnancy and Lactation Induces Long-term Alterations to the Mammary Gland in Mice," was published online, ahead of print.
The research also will be presented at ENDO 2021, the Endocrine Society's annual meeting, which runs from March 20-23.
INFORMATION:
Endocrinologists are at the core of solving the most pressing health problems of our time, from diabetes and obesity to infertility, bone health, and hormone-related cancers. The Endocrine Society is the world's oldest and largest organization of scientists devoted to hormone research and physicians who care for people with hormone-related conditions.
The Society has more than 18,000 members, including scientists, physicians, educators, nurses and students in 122 countries. To learn more about the Society and the field of endocrinology, visit our site at http://www.endocrine.org. Follow us on Twitter at @TheEndoSociety and @EndoMedia.
Durham, NC - Nuclear power offers an efficient, reliable way to provide energy to large populations - as long as all goes well. Accidents involving nuclear reactors such as those that took place in 1986 at Chernobyl and at Fukushima Daiichi after the March 2011 tsunami raise major concerns about what happens if the worst occurs and large numbers of people are simultaneously exposed to high levels of radiation. Currently, there are no effective, safe therapies for total body irradiation (TBI) - a condition known as acute radiation syndrome (ARS). That could change, ...
16th of March, Tuesday, 2021 -- Longevity medicine is a rapidly evolving branch of preventative precision medicine that is specifically focused on promoting healthspan and lifespan, utilizing aging biomarkers commonly referred to as aging clocks. Over the past decade advances in AI and machine learning enabled the development of deep aging clocks (DACs) and other novel tools to track the rate of aging. In parallel novel preventative and therapeutic interventions have been discovered or progressed into clinical trials. Many medical and public health professionals do not have time to read the thousands of research papers covering this new field and actively engage in cutting-edge innovation ...
Global drylands are experiencing faster-than-average warming and are also among the most vulnerable regions to climate change. Meteorological metrics all point to an emerging trend of increased surface aridity, raising concerns of land desertification and degradation. However, recent satellite observations also show lusher drylands, in apparent contradiction to the image of drylands becoming drier. In a new Review Article published in Nature Reviews Earth & Environment, an international team comprehensively examined global dryland aridity changes with evidence from the literature and various sources of Earth observations and numerical ...
New findings on the diet of Arctic foxes, determined by the condition of their teeth, show how varying climate conditions in the Arctic affect the animals that live there.
In a study published in Polar Biology, Peter Ungar, Distinguished Professor of anthropology at the University of Arkansas, and several co-authors analyzed tooth breakage and wear - both gross and micro - of Arctic foxes from Russia's Yamal Peninsula.
Studying the effect of varying climate conditions within this region helps scientists understand the impact of climate change on ...
When it comes to electric vehicles, particularly for heavy-duty trucks, the limitations of battery technology are often seen as the main barrier to widespread adoption. However, a new analysis concludes that it's the lack of appropriate policies around adoption incentives, charging infrastructure, and electricity pricing that prevents widespread electrification of commercial trucking fleets.
Researchers from the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California, Los Angeles published a new study that makes the case for prioritizing public policy to help move long-haul trucking from diesel to electric. Doing so will mean huge gains in addressing the ...
Kanazawa, Japan -- Any visitor to China will have noticed the spectacular roofs on buildings dating from imperial times. However, the question of how these roof tiles were produced has attracted relatively little attention from archaeologists. Now, a team of researchers has conducted a major study of tile ends unearthed at the Ximing Temple in Xi'an, yielding exciting insights into their production.
In a study published in Archaeological Research in Asia, researchers from Kanazawa University and the Chinese Academy of Social Sciences have revealed the significance of minute variations in the tile ends used in the roof of the famous Ximing Temple in Xi'an, built during the ...
Researchers from Tokyo Medical and Dental University (TMDU) identify a novel mechanism underlying hair thinning and loss during aging
Tokyo, Japan - Hair grows from stem cells residing in hair follicles. During aging, the capability of hair follicles to grow hair is successively lost, leading to hair thinning and ultimately hair loss. In a new study, researchers from Tokyo Medical and Dental University (TMDU) and the University of Tokyo identified a novel mechanism by which hair follicles lose their regenerative capabilities.
Hair follicles are mini-organs from which new hair constantly grows. The basis for new hair growth is the proper function of hair follicle stem cells (HFSCs). HFSCs undergo cyclic symmetric and asymmetric cell divisions ...
A genetic defect could hold the key to preventing or delaying the onset of a debilitating eye disease that can lead to vision loss and blindness.
MacTel (macular telangiectasia type 2) affects one in 1,000 Australians. Symptoms include slow loss of vision, distorted vision and trouble reading. Because early signs of the disorder are subtle, it is difficult to diagnose.
Researchers have identified an additional seven regions in the human genome that increase the risk of developing the condition, including a rare DNA mutation in the PHGDH gene, which will help clinicians to better diagnose and treat ...
Nanograined metals and alloys, whose grain size is less than 100 nm, exhibit extremely high strength and high ductility, possessing excellent mechanical properties. Nanograined materials, however, have a large number of grain boundaries and hence high total grain boundary energy. At a temperature higher than a critical temperature, grains in nanograined materials will grow spontaneously to reduce the grain boundary energy, leading to thermal instability of the materials. A common approach to enhance the thermal stability is via grain boundary energy segregation, which thermodynamically lowers the grain boundary energy and kinetically pins ...
An inter-disciplinary team of researchers led by Prof. Qian Peiyuan, Chair Professor at the Hong Kong University of Science and Technology (HKUST)'s Department of Ocean Science and Division of Life Science has unraveled how a novel microbial small molecule released by Streptococcus mutans (S. mutans) - a bacterium commonly found in the human oral cavity - is connected to dental caries development using a synthetic biology approach, offering new insights to the health impact of the human oral microbiota and facilitating future research on the prevention of tooth decay. The research findings were recently published in the prestigious scientific journal Nature Chemical Biology and reported by Nature as one of the research highlights.
Every wetted surface on our ...
