Monitoring the path of microplastics through the intestines of a living organism

The UAB research team was able to track the movement of microplastics during their journey through the intestinal tract of a living organism and illustrate what is happening along the way. The study, conducted on Drosophila melanogaster using electron microscopy equipment developed by the researchers themselves, represents a significant step towards a more accurate health risk analysis from exposure to these contaminants.

The behavior of micro- and nanoplastics (MNPLs) in the body is a question that is currently impossible to answer in humans, and in vitro models are of no use. So, you need to look for models that can answer this question. In addition, there are limitations in current methodologies for detecting and quantifying their presence in various human biological samples, which prevents an accurate assessment of health risk.

In this context, researchers from the Mutagenesis Research Group of the Autonomous University of Barcelona (UAB) were able to follow the tracking of MNPLs in their “journey” from the environment to the interior of a living organism. They did this by developing tools based on it electron microscopy and in the larvae of Drosophila melanogastral – a model organism that is widely used to study biological phenomena and processes.

The research team studied the behavior of MNPL on their way with commercial nanometer-sized polystyrene. The resulting “photographic report” allowed them to see the interaction of MNPLs with the microbiota and cell membranes that repair inside the gut, their ability to cross the intestinal barrier and their presence in hemolymph, which is equivalent to human blood, and in blood cells corresponding to our lymphocytes.

“In addition to creating a new methodological approach, our study confirms the great benefits of the Drosophila melanogasteras model for identifying potential adverse effects associated with the uptake of these contaminants,” explains Ricardo Marcos, a researcher at the Department of Genetics and Microbiology. UAB and Research Coordinator.

Nanometric effects

Evaluation of the biological effects at different stages of larval life showed that, although no significant toxicity was observed, the exposure elicited a broad molecular response by altering the expression of genes involved in the overall stress response. oxidative damage and genotoxicity, as well as in genes associated with the response to physical damage to the intestinal barrier.

“Our work adds information about what happens in terms of effects when exposure occurs to nanoplastics that are due to them small sizeare of particular importance to us because of their greater ability to break down biological barriers and produce toxicological effects that can affect the health of organisms, including humans, ”says Alba Hernandez Bonilla, UAB researcher and co-author of the study.

So far, most MNPL impacts have been carried out in micro- and even millimeter ranges and in aquatic models, mostly marine. In vivo studies using nanoplastics are virtually non-existent. It is in this context that the study, which used methodologies that have never been used for these purposes before, is clearly relevant, the researchers note.

The study was published recently in the Journal Environmental Sciences: Nana and is part of the European PLASTICHEAL project, coordinated by UAB, which aims to provide regulators with new methodologies and solid scientific evidence to create knowledge base for adequate MNPL risk assessment.