Environmental factor – July 2022: Inhaled nanoparticles during pregnancy can infiltrate fetal tissues

Small particles inhaled during pregnancy can affect fetal growth and development, according to research in animal models funded by the NIEHS Outstanding New Environmental Scientist (ONES) program.

At Rutgers, Stapleton is an assistant professor at the Ernesto Mario College of Pharmacy, the joint graduate program in toxicology. (Photo courtesy of Phoebe Stapleton)

Phoebe Stapleton, Ph.D.Associate Professor at Rutgers Ernest Mario School of Pharmacy and faculty member at Rutgers Institute for Environmental and Occupational Health Sciences has focused her research on understanding the molecular mechanisms that impede blood flow to the developing fetus after exposure to environmental pollutants during pregnancy.

Using a rat model, Stapleton showed that nanoparticles of the metallic titanium dioxide inhaled by a pregnant rat could pass from the rat’s lungs to the placenta. The placenta’s job is to filter out substances that can harm the fetus. Stapleton’s work showed that in the case of nanoparticles, the placenta is not an effective barrier.

Research is rooted in the question of whether such exposures lead to restrictions on the mother’s blood flow, which in turn can lead to low birth weight, premature birth and even miscarriage.

“Maternal exposure impairs overall systemic blood flow,” Stapleton said. There is a clear effect downstream. There may be reduced blood flow in the male liver exposed to the nanoparticles. But in the pregnant female of the animal, you can see weakness in the fetal pups. There is a more pronounced, overall, and more visible and tangible effect on the mother’s impairment of blood flow.”

While Stapleton’s work continues, her ONES grant hypothesis is that increased intake of folic acid during pregnancy can help counteract the worst effects of blood flow restriction.

Nanoparticles spreading everywhere

Metal nanoparticles aren’t Stapleton’s only concern. Her research is also looking at another potential threat to fetal health: plastic nanoparticles. Given the huge amount of microplastics now in the environment, inhaling or ingesting plastic nanoparticles is inevitable.

The fact that nanoparticle contamination is so widespread made Stapleton’s research particularly difficult. While working with pregnant rats that had been exposed to titanium dioxide, her team discovered that their control animals contained very high amounts of titanium likely due to the food the rats were feeding on.

“We ended up with ingestion exposure in the controls and then exposure to ingestion and inhalation in the base group,” she noted. “However, this may provide a more accurate picture of what is really happening in the world outside of controlled conditions in the laboratory.”

Stapleton noted that the same problem arose in experiments involving plastic. Her team noticed that many components in the labs, such as bottles, flasks, and pipettes, are made of plastic. The trick is to use sophisticated techniques such as transmission electron microscopy and dark-field microscopy to look for the specific polymer used for exposure during the experiment as opposed to other polymers that pollute the surrounding environment.

electronically unintentionally

After discovering that nanoparticles can affect blood flow and transit from the mother’s lungs and gastrointestinal tract to fetal tissues and the brain, Stapleton’s next research question is whether these particles remain after birth.

“Could you be born with these substances that are already in you?” asked Stapleton. “Can particle transmission change the physiology of the next generation? We know that these particles now have local cellular interactions with placental tissue – what is the toxic effect?”

Particles have been in our bodies since our ancient ancestors discovered how to make fire, tiny particles fly off when matter burns. But technological advances have now given us the ability to identify the particles we inhale.

“When we think about neurological disorders or diseases that suggest we don’t know where they came from, this begs the question whether particle interaction at the cellular level plays a role for some of them,” she said.

Stapleton said she hopes the end result of her research will have potential implications for policy, although she acknowledges that pollutants we don’t fully understand can be difficult to control or regulate. And while technological advances are needed, especially to sort through simultaneous exposure to such fine particles, the Stapleton model and ongoing research has highlighted the importance of understanding the effects of exposure on maternal and fetal health.

Lingamanaidu (Ravi) Ravichandran, Ph.D., a management health scientist at NIEHS Exposure, Response, Technology Branch who works oversees Stapleton’s work. “The model could provide a way to further understand the biological consequences after acute or chronic exposure to nanoparticles, particularly their impact on maternal health and pregnancy outcomes.”

the quote: D’Errico JN, Doherty C, Reyes George JJ, Buckley B, Stapleton PA. 2022. Distribution of titanium to the mother, placenta, and fetus after repeated inhalation of titanium dioxide nanoparticles during pregnancy. Placenta 121: 99-108.

(Kelly Christensen is a contract writer and editor for the NIEHS Office of Communications and Public Liaison.)

from San Jose News Bulletin https://sjnewsbulletin.com/environmental-factor-july-2022-inhaled-nanoparticles-during-pregnancy-can-infiltrate-fetal-tissues/