Are probiotics an unmitigated good? Could intestinal probiotics evolve in the gut and cause harm?
For many, probiotics are full of treasures, which play a key role in intestinal function. But a new study in Cell Host＆Microbiome offers a critical look at the benefits of probiotics. Things are rarely so straightforward! The new study indicates that under certain conditions, the bacterium was likely to evolve and harmed the host.
Probiotics play a useful role by helping create a healthful bacterial balance within the host's gut. Our bodies already contain around 1.5 kilograms of probiotic bacteria. These microorganisms also occur in fermented foods such as yogurt, kimchi, miso, and some types of cheese.
In the public's eyes, probiotic is a promising field for the development of functional foods in the future lies in its important function on the host for its health benefit(e.g. help digestion, Lower blood pressure, improve cognitive functioning) and prophylaxis disease(slow irritable bowel syndrome).
However, as more and more people begin to consume Probiotics’ benefit, emerging research cautions that probiotics may not work in the same way for everyone and that some strains of probiotics may not even be safe.
A new study offers a critical look at the therapeutic benefits of probiotics. Scientists from the Washington University School of Medicine in St. Louis, MO, have investigated the behavior of a strain of Escherichia coli in the intestines of mice.
Gautam Dantas, Ph.D. — a professor of pathology and immunology — led the new research. Prof. Dantas and colleagues chose the probiotic E. coli Nissle 1917, because researchers believe it has anti-diarrheal properties. They wanted to see how the bacterium behaves in mice's digestive tracts, so they used rodents that had four different kinds of the gut microbiome.
After 5 weeks, the researchers analyzed the rodents' microbiomes. They found that the bacterium had changed to develop new characteristics. Under certain conditions, the bacterium harmed the host, eating the protective layer that lines the intestine. Previous research has linked damage in this protective layer with irritable bowel syndrome.
"In a healthy, high-diversity background we didn't capture a lot of adaptation, maybe because this is the background that Nissle is used to," reports first study author Aura Ferreiro.
"But you have to remember that quite often we wouldn't be using probiotics in people with a healthy microbiome. We'd be using them in sick people who have a low-diversity, unhealthy microbiome. And that seems to be the condition when the probiotic is most likely to evolve."
Reference：Medical News Today：https://www.medicalnewstoday.com/articles/324834.php