“This is the first study that demonstrates how chronic exposure to e-cigarettes increases the gut’s susceptibility to bacterial infections, leading to chronic inflammation and other health concerns,” said the researcher, Soumita Das, Associate Professor, University of California, San Diego.
“Given the importance of the gut barrier in the maintenance of the body’s immune homeostasis, the findings offer valuable insight into the potential long-term harmful effects chronic use of e-cigarettes on our health,” Das added.
For the study, published in the journal iScience, the team used 3D models of human intestinal tracts generated from patient cells and simulated what happens when e-cigarette vapors enter the gut lining.
To produce the 3D gut organoids, the researchers collected stem cells from patients’ biopsies during colonoscopies and grew them in vitro.
The stem cells differentiated into the four different cell types that make up the gut lining. The team then exposed the organoids to e-cigarette liquid vapor, mimicking the frequency of a chronic vaper.
They noted that epithelial tight conjunction markers, which are zipper-like proteins that form the gut’s first physical barrier, began to break or loosen, causing pathogens from the vapor to seep into the surrounding immune system, wreaking havoc on protective epithelial cells that lie just beneath.
Such cells act as a defence against infection by clearing pathogenic microbes and initiating certain immune responses in the body. When exposed to the e-cigarette liquid, the cells were quickly overwhelmed, unable to effectively clear pathogens, resulting in gut inflammation.
“Anything we eat or drink, our lifestyle choices in other words, has the ability to impact our gut microbes, the gut barrier and overall health. Now we know that what we smoke, such as e-cigarettes, negatively impacts it as well,” a researcher said.