- A new study from the University of Rhode Island suggests that microplastics accumulating in the brain might raise the risk of Alzheimer’s in people with a genetic predisposition.
- In tests on mice, researchers observed behavioral and memory changes associated with the Alzheimer’s-related APOE4 gene after exposure to micro- and nanoplastics.
- While the study has limitations, it contributes to the growing research on microplastics’ potential health effects, emphasizing actions like reducing plastic use and eating more fruits and vegetables to help mitigate risks.
Nearly seven million Americans are living with Alzheimer’s disease in the United States, according to the Centers for Disease Control and Prevention. That number is expected to double by 2060. The disease currently has no cure. However, a new study sheds light on a small factor that could influence your chances of developing Alzheimer’s in the future: microplastics.
In August, researchers from the University of Rhode Island published their study findings in Environmental Research Communications, suggesting that microplastics, which are found everywhere from the fish we eat to shedding off food containers, coming from tea bags, and even in our water, have migrated to the brain and could trigger “disease-like states” in people with a genetic predisposition to Alzheimer’s.
To come to this conclusion, the team used 64 mice (half male, half female) engineered to have either the APOE3 genetic biomarker that carries a neutral risk of developing the disease, or APOE4, the marker associated with higher Alzheimer’s risk. They then exposed the test mice to water contaminated with both nano- and microplastics at extremely high doses to simulate what a lifetime of exposure might look like for humans.
After the exposure period, the researchers conducted a series of behavioral tests and then examined the animals’ tissues. These tests assessed everything from how the mice explored new environments to whether they noticed when a new object was introduced into their area, aiming to measure changes in their short-term memory. Tissue samples were also analyzed for the presence of plastics and markers of immune activity in the brain.
As for detecting actual plastic particles, the team found many hidden in the mice’s brains. For behavioral assessments, the researchers separated the findings based on sex and genetics. In the open-field test, which measures how a mouse explores a new environment, male mice carrying the Alzheimer’s-linked APOE4 gene and given plastic-laced water spent more time in the center and resting there, indicating a shift from their usual behavior. Female APOE4 mice, however, showed changes on the novel object recognition test, where they were slower to investigate a new object in their space and spent less time with it. The researchers note this as a sign of weaker recognition memory. Mice with the neutral APOE3 gene did not exhibit these same issues.
“I’m still really surprised by it,” Jaime Ross, one of the paper’s authors and a professor of neuroscience at the University of Rhode Island, told the Washington Post. “I just can’t believe that you are exposed to these particles and something like this can happen.”
What Ross also wants to clarify is that if you carry the APOE4 gene, it doesn’t automatically mean you’ll develop Alzheimer’s later. “I don’t want to scare anybody,” she said. “But it is the largest known risk factor.” However, what this study shows is that external risks, potentially including microplastics, could increase their risk. (As The Washington Post noted, other studies have also shown that high-fat diets can cause cognition and memory issues in mice that carry the gene.)
It’s important to note that the study does have limitations, such as using lab-made plastics that are not exactly like those encountered in everyday exposure today. However, the study and its findings contribute to a growing body of concerning research on the effects of microplastics.
In July, Food & Wine reported on a recent study showing that microplastics could be causing liver damage, and in early September, we shared another report indicating that microplastics could be making the blood-brain barrier “leaky,” allowing toxins to enter. While all of this may sound a bit scary, there are steps you can take to limit your exposure, such as replacing key household items like non-stick cookware, plastic cutting boards, and certain sponges. You can also combat these tiny particles by eating your favorite fruits and vegetables, which scientists say can help counteract the negative effects of microplastics in your body.
Source link
