Topline
Researchers have discovered gut microbes that could one day be harnessed to help diagnose, prevent and treat conditions like obesity, prediabetes and type 2 diabetes, according to research published Wednesday in Nature, the latest breakthrough in our understanding of the human microbiome that promises to unlock a new era of medical innovation.
Gut bacteria signal promise for new treatments for obesity and diabetes, research suggests.
Key Facts
Certain bacteria were found to be more common in the poop of people with higher insulin resistance, according to an analysis of fecal samples provided by more than 300 adults at their regular health checkups, which give an insight into the gut microbiome, the trillions of bacteria living inside of us that are thought to have a profound impact on our health.
Resistance to insulin—a hormone that helps regulate blood sugar levels—means more sugar remains in the blood and can lead to weight gain, prediabetes (a serious condition of elevated blood sugar that doesn’t warrant a diabetes diagnosis) and type 2 diabetes.
The researchers, led by Hiroshi Ohno at the RIKEN Center for Integrative Medical Sciences in Japan, noted that the microbiome of people with higher levels of carbohydrates (sugars) in their feces and higher insulin resistance were dominated by Lachnospiraceae bacteria.
Conversely, the microbiome of people with lower insulin resistance and lower fecal carbohydrates contained more Bacteroidales bacteria than other types.
By growing the bacteria in a lab, the researchers sought to identify species common in people with low insulin resistance that could be used to bring down blood sugar levels in people resistant to insulin, which they then tested in obese mice.
The approach—particularly with a Bacteroidales species called Alistipes indistinctus—was promising, the researchers said, lowering blood sugar, leading to “significantly improved” insulin resistance and lowering the amount of carbohydrates available to the mice.
Crucial Quote
The study signposts a number of potential avenues that could be explored for future therapies and diagnostic tools in humans, said Ohno. As Lachnospiraceae bacteria are associated with insulin resistance, Ohno said they could be a good thing to test for to indicate prediabetes. “Likewise, treatment with probiotics containing A. indistinctus might improve glucose intolerance in those with pre-diabetes,” Ohno said. Though the study suggests promising avenues for future work, Ohno stressed they “need to be verified in human clinical trials before” any probiotic can be recommended as a treatment for insulin resistance.
What To Watch For
Tadashi Takeuchi, a researcher at Stanford University and first author of the study, told Forbes the group is analyzing other associations between the gut microbiome and metabolism. Takeuchi stressed there are also a number of challenges that must be overcome in order to bring Lachnospiraceae bacteria to clinics. For example, Takeuchi said the group contains a “wide array of gut bacterial species” and more research is needed to outline what they do and to identify how they can be used to indicate dysfunctions like prediabetes. This work could be challenging, Takeuchi warned, explaining that the characteristics of Lachnospiraceae bacteria are “largely unknown” because their “extreme sensitivity to oxygen” makes them difficult to culture in labs. This sensitivity would also hinder efforts to develop A. indistinctus as a commercial probiotic, Takeuchi said, adding that to his knowledge no commercial products contain the strain.
Key Background
A variety of treatments have emerged as our understanding of the gut microbiome and its role in health has developed. Fecal transplants, which involve placing stool and bacteria from healthy donors into a sick individual, have been used to treat potentially lethal infections like C. difficile for years now. Researchers are looking into applying the insights to a variety of issues like obesity, Crohn’s disease and allergies, as well as making treatment easier through the use of fecal pills. The Food and Drug Administration approved the first fecal pill—made of healthy gut bacteria found in feces to combat C. diff—targeting the microbiome in April, a step towards boosting access to fecal transplants.
Tangent
The possibility of applying what we know about gut microbes to build new ways of treating obesity comes amid an explosion of drugs doing the very same. Drugs like semaglutide—marketed as Ozempic and Wegovy—and Mounjaro are at the leading edge of a wave of new pharmaceutical weight loss options that experts say will be a game changer for tackling obesity. Demand for the drugs, fueled by the promise of tackling one of the biggest public health threats of our time, is so strong that the companies producing them are struggling to keep up. Novo Nordisk, which produces Ozempic and Wegovy, has admitted supplies are likely to be limited for years to come as it struggles to ramp up production to meet stellar demand. The drugs are slated to become some of the best selling drugs of all time.
Further Reading
I Contain Multitudes (Book by Ed Yong)
Does the microbiome hold the key to chronic fatigue syndrome? (Observer)
Unlocking the ‘gut microbiome’ – and its massive significance to our health (Guardian)