Microplastics could obstruct blood vessels from the brain and indirectly disturb cognitive functions, according to a team of researchers.
- A study reveals that microplastics can obstruct brain blood vessels by trapping immune cells, thus disturbing blood circulation and brain functions.
- The largest particles (5 micrometers) cause more prolonged blockages than smaller particles (80 nanometers), which are eliminated more quickly.
- The mice exposed to microplastics presented a decrease in their locomotion, a spatial memory loss and a reduction in their motor capacities. Most of its neurocomportal effects were reversible.
We find them everywhere in our environment. Microplastics, these invisible particles from the degradation of plastics, can penetrate into the human body by ingestion, inhalation or even through medical devices. Today they are suspected of being at the origin of many health problems, such as cancers or urinary disorders.
A new study, published in the journal Science Advancestoday highlights the impact of these microplastics on the blood vessels of the brain in mice. This discovery reveals a mechanism by which microplastics indirectly disrupt cognitive functions, without crossing the blood-brain barrier.
The impact of microplastics on the blood infusion of the brain
Previous work had already shown that microplastics can induce immune responses and alter the cellular functions of humans, but the underlying mechanisms were so far vague. In this study, 8 -week mice received an intravenous injection of fluorescent microplastics of different sizes – 5 micrometers (µm), 2 µm and 80 nanometers (nm) – at concentrations simulating human exposure. The researchers used advanced technology to follow these particles in the brain blood vessels in real time.
Analyzes have revealed that immune cells, such as neutrophils and macrophages, phagocyte microplastics, which changes their morphology and their ability to circulate. These trapped cells obstruct the capillaries, reducing brain blood infusion in less than 30 minutes. Unsurprisingly, the largest particles (5 µm) cause more prolonged blockages than smaller particles (80 nm), which are eliminated more quickly, according to a press release.
Effects on mouse behavior
Behavioral tests, including memory, coordination and endurance exercises, have shown that mice exposed to microplastics have a decrease in their locomotion, a spatial memory loss and a reduction in their motor capacities. Although these neurocomptal alterations were reversible in four weeks, certain vascular obstructions persisted.
If this study highlights the potential risks of microplastics for the health of animal models, researchers insist on the importance of continuing research to understand the long -term consequences in humans.
