Prenatal BPA exposure associated with sleep changes in mice


Sleep Health | Sleep Review

With thousands of chemicals swirling around our environment, exposure to any number is virtually inevitable. Through the work of researchers such as Deborah Kurrasch, PhD, the effects of many of these chemicals are thoroughly researched.

“Manufacturers follow regulatory standards; it’s not up to manufacturers to demonstrate the safety of chemicals in consumer products,” says Kurrasch, a researcher at the University of Calgary’s Hotchkiss Brain Institute (HBI) and the Cumming School of Alberta Children’s Research Institute Medicine, in a press release. “Scientists play a crucial role and meticulously determine where the risks lie.”

Kurrasch’s research for the past decade has focused on a chemical that is well known: bisphenol A, also known as BPA. This chemical is often found in plastics, canned food and even in thermal receipts. Studies from Kurrasch’s laboratory add to the collective research showing the harms of exposure to this industrial compound.

The latest study from Kurrasch’s lab, published in Science Advances, suggests that continued vigilance is required. A postdoctoral fellow in her laboratory, Dinu Nesan, PhD, studied the effects of low BPA exposure on pregnant mice and the brain development of their offspring.

“Our goal was to model BPA levels that correspond to those that pregnant women and developing babies are normally exposed to,” says Kurrasch. “We deliberately did not use a high dose. In fact, our doses were 11 times and nearly 25 times lower than those rated as safe by Health Canada and the FDA, respectively. Even with these low values, we saw effects on prenatal brain development in the mice. “

Using this BPA exposure model, Nesan found noticeable changes in the region of the brain that is responsible for circadian rhythms, the suprachiasmatic nucleus, which is located in the hypothalamus. With prenatal exposure to these low levels of BPA, the suprachiasmatic nucleus was unable to develop properly. This change can affect sleep, activity levels, and other behaviors.

“We previously showed that embryonic exposure to low-dose BPA can affect the timing of neurons development in zebrafish, but it was unclear whether a similar effect would be seen in a mammalian model with more similarities to humans,” says Nesan , Lead author of the study, in a press release. As neurons develop, they rely on the right signals to guide them. When neurons develop too early, the signals they experience are different, which can lead to developmental errors such as migrating to the wrong place, developing to the wrong type of neuron, or forming inappropriate connections. These mistakes can lead to behavior changes later in life.

“Our study shows that prenatal exposure to BPA in pregnant mice influences the timing of neuronal development in the fetal brain, which has a lasting effect on behavior. Offspring exposed to BPA during pregnancy are awake longer and show hyperactivity. Prenatal BPA exposure appears to alter the brain’s circadian signals, resulting in animals having increased energy levels and spending less time resting, ”says Nesan.

The researchers hope their findings will put pressure on regulators to continually review their regulations on safe levels of BPA.

[RELATED: Endocrine-Disrupting Chemicals Linked to Sleep Troubles in Menopausal Women]

“We believe there is an incredible wealth of data to show that the BPA exposure guidelines are not yet at the appropriate level, including the EU (European Union) leading the way in this regard, but their ‘safe’ levels are still twice the dose we used in our study, “says Kurrasch.” We hope that our research will remind you that low-dose BPA can still cause measurable and significant changes. “

Their message on how to interpret this research is simple:

  • Limit your BPA exposure as best you can.
  • Maintain smart plastic practices in your kitchen, such as: B. not to heat and if possible to use glass or stainless steel.

This research was carried out in collaboration with Michael Antle, PhD, Professor of Psychology and a member of the HBI.

Photo 120374340 © Andy0man |

Source Link

Leave a Reply