The Body Fights Back

By MiNDFOOD

FILE PHOTO: Colonies of E. coli bacteria grown on a Hektoen enteric (HE) agar plate are seen in a microscopic image courtesy of the U.S. Centers for Disease Control (CDC).  File Photo - RC12C72AE570
FILE PHOTO: Colonies of E. coli bacteria grown on a Hektoen enteric (HE) agar plate are seen in a microscopic image courtesy of the U.S. Centers for Disease Control (CDC). File Photo - RC12C72AE570
Researchers have identified a molecule that serves as natural protection against one of the most common intestinal pathogens, Salmonella.

Salmonella is a common form of food poisoning caused by contaminated food or water, chicken and eggs pose a very high risk of Salmonella infection. Modern refrigeration and properly cooked food help prevent against the spread of Salmonella, however salmonella is 1 of the 4 key global causes of diarrhoea diseases.

New research has found that some people are better able to fight infection by Salmonella and other intestinal pathogens.  

Researchers at the Stanford University School of Medicine have identified a molecule that serves as natural protection against one of the most common intestinal pathogens which could lead to the development of better treatment strategies.

Propionate, a byproduct of metabolism by a group of bacteria called the Bacteroides, inhibits the growth of Salmonella in the intestinal tract of mice, according to the researchers. The researchers determined that propionate doesn’t trigger the immune response to thwart the pathogen. Instead, the molecule prolongs the time it takes the pathogen to start dividing by increasing its internal acidity.

Salmonella infections often cause diarrhoea, fever and abdominal cramps. Most people recover within four to seven days. However, the illness may be severe enough to require hospitalisation for some patients.

Different responses to exposure

“Humans differ in their response to exposure to bacterial infections. Some people get infected and some don’t, some get sick and others stay healthy, and some spread the infection while others clear it,” said Denise Monack, PhD, professor of microbiology and immunology and the senior author of the paper. “It has been a real mystery to understand why we see these differences among people. Our finding may shed some light on this phenomenon.”

For years, scientists have been using different strains of mice to determine how various genes might influence susceptibility to infection by intestinal pathogens. But this is the first time that researchers have looked at how the variability of gut bacteria in these mice might contribute to their different responses to pathogens.

Reducing the impact of salmonella

In addition, the researchers will work to identify additional molecules made by intestinal microbes that affect the ability of bacterial pathogens like Salmonella to infect and “bloom” in the gut. They are also trying to determine how various diets affect the ability of these bacterial pathogens to infect and grow in the gut and then shed into the environment. “These findings will have a big impact on controlling disease transmission,” Monack said.

The findings could also influence treatment strategies. Treating Salmonella infections sometimes require the use of antibiotics, which may make Salmonella-induced illness or food poisoning worse since they also kill off the “good” bacteria that keep the intestine healthy, according to Monack. Using propionate to treat these infections could overcome this limitation. “Reducing the use of antibiotics is an added benefit because overuse of antibiotics leads to increased incidence of antibiotic-resistant microbes,” Monack said.

Ever wondered how to cook rice properly, and prevent against Salmonella? Find out here

Materials provided by Stanford Medicine. Original written by Kimber Price. 

SHARE THIS ARTICLE

Print Recipe

BECOME A MiNDFOOD SUBSCRIBER TODAY

Let us keep you up to date with our weekly MiNDFOOD e-newsletters which include the weekly menu plan, health and news updates or tempt your taste buds with the MiNDFOOD Daily Recipe. 

Member Login