Obesity Could Be Prevented By Genetically Modified Bacteria
by Lisa Winter
Photo credit: E. coli. Credit: Eric Erbe/Christopher Pooley/USDA
Despite what Dr. Oz may have told you, there aren’t any miraculous supplements that will give any long-term weight loss benefits. At this point, there aren’t even very many FDA-approved medications that effectively treat obesity and related metabolic diseases. However, a group of researchers led by Sean Davies of Vanderbilt University have genetically altered bacteria that reside in the gut, and have been shown to prevent weight gain, even over a month after the treatment ended. The results of the study have been published in The Journal of Clinical Investigation.
The researchers genetically modified a harmless strain of E. coli (Nissle 1917) to produce the compound N-acylphosphatidylethanolamine (NAPE), which acts as an appetite suppressant. The bacteria was added into the drinking water of mice who were fed high-fat diets over the course of eight weeks. The mice with the modified bacteria gained less weight, consumed less food, and had fewer markers for diabetes than mice that drank regular water or water with unmodified bacteria. What’s more, the mice that consumed the NAPE-producing bacteria continued to exhibit these effects for 4-6 weeks after the treatment was stopped.
The human gut contains about 100 trillion microorganisms, the majority of which come from around 40 species. Many of these provide many beneficial services in terms of digestion and eliminating disease-causing microbes, so it isn’t much of a stretch that this particular strain of E. coli, a known probiotic, could be manipulated for use in weight loss. Unfortunately, there are some key changes that will have to be made prior to clinical trials in humans.
The modified bacteria, as it currently stands, is resistant to antibiotics. This was done to make it easier to grow in the lab for experimentation purposes. While the bacteria hasn’t shown any signs of being harmful, the researchers will need to find an alternative before it can be used in humans. The alternative will also need to go rigorous testing to ensure it does not pose any health risks.
Obesity has become a world-wide epidemic that kills 2.8 million people each year. Type 2 diabetes affects 347 million people globally, and over 80 percent of people diagnosed are also considered obese. The disease was the seventh leading cause of death in the US in 2006, though it can also lead to nerve damage, renal failure, stroke, and the need for limb amputation.
Though obesity is not as cut and dry as it sometimes seems, future testing of this modified bacteria may also pit mice on a high fat diet consuming the bacteria versus mice on leaner diets, with and without exercise in order to maximize the benefit and really combat obesity.