Scientists hope the same bacteria could help keep people from becoming obese

Jul 23, 2014 07:58 GMT  ·  By

While carrying out a series of experiments on laboratory mice, researchers with Vanderbilt University in the US identified a bacterium that they say can help these rodents maintain a pleasant waistline despite being fed a high-fat diet.

In a recent paper in the Journal of Clinical Investigation, the specialists detail that the bacterium in question is a probiotic, i.e. a microorganism that is beneficial to one's health when consumed.

The bacterial strain that was used to prevent obesity in laboratory mice is a modified version of E. coli, and it works by producing a lipid compound dubbed NAPE. This compound is naturally occurring in the gut, Science Daily reports.

Specifically, it is synthesized in the small intestine in response to feeding, and, shortly after being produced, it gets converted into another compound dubbed NAE, that works by limiting food intake and reducing weight gain.

“The types of bacteria you have in your gut influence your risk for chronic diseases. We wondered if we could manipulate the gut microbiota in a way that would promote health,” explains senior investigator Sean Davies.

Having genetically engineered the NAPE-producing bacterial strain, the scientists exposed mice to it by adding it to the rodents' water. One other group of mice was offered water containing neutral bacteria, and served as a control.

The animals were then kept on a high-fat diet for 8 consecutive weeks. When compared to the control group, the mice that got to feast on the NAPE-producing bacteria ate less, stored less body fat, and had reduced insulin resistance.

Writing in the Journal of Clinical Investigation, the scientists say that the beneficial effects of consuming the modified E. coli bacteria manifested themselves for up to 4 weeks after the mice no longer had the microorganism added to their water.

What's more, the Vanderbilt University researchers say that, even 12 weeks after being exposed to the bacterial strain, the rodents were slimmer and healthier than those in the control group. This brings new hope when it comes to treating obesity in human patients.

“This paper provides a proof of concept. Clearly, we can get enough bacteria to persist in the gut and have a sustained effect. We would like for that effect to last longer,” scientist Sean Davies comments on the outcome of this series of experiments.

“Of course it's hard to speculate from mouse to human. But essentially, we've prevented most of the negative consequences of obesity in mice, even though they're eating a high-fat diet,” the researcher goes on to explain.