Appetite Suppressing Bacteria Could Become the New Diet Drink
Would you be willing to swill down a diet drink that contains appetite suppressing bacteria? Here is what one research team found when mice fed a high fat diet also drank just such a beverage.
In a recent study presented at the 249th National Meeting & Exposition of the American Chemical Society, scientists demonstrated that treating obesity is possible, simply by orally incorporating specific bacteria in the digestive tract of animals.
The foundation of their research is based on a growing number of related studies that are discovering that human health may be dependent upon the type of microbial biome that resides in the digestive tract.
For example, fecal transplant has been done as a way to fight bad bacterial infections―such as Clostridium difficile infections contracted in hospitals and nursing homes―with good bacteria from a healthy donor. Furthermore, fecal transplant for treating metabolic disease and obesity is an ongoing investigation in several labs.
The bonus to investigating the potential and efficacy of a bacteria-spiked beverage is that the application of bacteria by this route is significantly less invasive and more appealing to patients than the idea of undergoing a fecal transplant. Moreover, the bacteria used to treat a condition can be genetically designed and controlled more exactly.
In the study presented at the meeting, the researchers explained that special chemical compounds called “NAPEs” (N-acyl-phosphatidylethanolamines) are naturally produced in the small intestine after a meal during which the compounds are then metabolically converted by a special enzyme into a new form called “NAEs” (N-acyl-ethanolamines). NAEs are potent appetite suppressing lipid compounds that signal the brain that the body has taken in food and is full.
To determine whether extra doses of brain-signaling NAEs in the digestive tract could help prevent obesity, the researchers genetically engineered a strain of probiotic bacteria that could express additional NAES into the digestive tract of its host. To test the efficacy of the engineered bacteria, the researchers turned to a strain of mice that, when fed a high-fat diet, develop obesity, signs of diabetes and fatty livers. These high fat diet mice were divided into two groups: one group was fed normal drinking water, whereas the second group was fed water spiked with the engineered bacteria.
After 8 weeks of treatment, the researchers found that the mice drinking the engineered bacteria gained 15 percent less weight over the eight week test period compared to the group of mice fed regular water. In addition, the livers and glucose metabolism of the bacteria-fed mice were improved compared to the plain water fed control mice and remained lighter and leaner up to 12 weeks after the treatment ended.
Additional studies were performed to further demonstrate that using engineered bacteria to treat obesity is possible by doing similar studies on a special type of mouse that lacked the enzyme to make NAEs from NAPEs. When this strain of mouse was given a bacterium that expresses NAEs, they too fared better than the control mice while on a high fat diet.
“This suggests that it might be best to use NAE-making bacteria in eventual clinical trials,” stated lead researcher Sean Davies, an assistant professor at Vanderbilt University School of Medicine, especially if it turns out that some people don’t make very much of the enzyme that converts NAPEs to NAEs. “We think that this would work very well in humans.”
However, the road to clinical human trials and eventual obesity prevention or treatment may be a long one due to the concern that a treated patient could inadvertently transmit these genetically engineered bacteria to another person by fecal exposure.
“We don’t want individuals to be unintentionally treated without their knowledge,” says Davies. “Especially because you could imagine that there might be some individuals, say the very young or old or those with specific diseases, who could be harmed by being exposed to an appetite-suppressing bacteria. So, we are working on genetically modifying the bacteria to significantly reduce its ability to be transmitted.”
For more about the connection between bacteria and obesity, here is an article on how thin people poop may become an obesity cure.
Reference: American Chemical Society news release― “Special microbes make anti-obesity molecule in the gut”