Bacteria in the gut can accurately reveal a person's true age

billions of bacteria are home in our guts, and they may help regulate everything from our ability to digest food to how our immune system functions. But scientists know little about how the system, called the gut microbiome, changes over time, or what a "normal" gut microbiome looks like. Now, by studying gut bacteria in thousands of people around the world, a team of researchers has come to the conclusion that the gut microbiome is a very accurate biological clock that predicts the age of most people, with an error of less than a few years.
To find out how the gut microbiome changes over time, Alex Zhavoronkov, a longevity researcher at InSilico Medicine, an artificial intelligence startup based in Rockville, Md., and colleagues studied more than 3,600 samples of gut bacteria from 1,165 healthy people worldwide. About a third of these samples came from people aged 20 to 39, a third from people aged 40 to 59 and the last third from people aged 60 to 90.
the researchers then used machine learning to analyze the data. First, they trained their computer programs using the ages of 95 different types of bacteria from 90 percent of the samples and the people who provided them--- a deep learning algorithm that approximates how neurons work in the brain. They then asked the algorithm to predict the age of the person who provided the remaining 10 percent of the sample. Their program accurately predicts the age of these people, with an error of less than 4 years. They published their findings on the preprinted server bioRxiv. Of the 95 different types of gut bacteria, they found that 39 of them were the most important in predicting age.
Zhavoronkov and his colleagues found that as people get older, some bacteria become richer, such as Eubacterium hallii. Hollyobacteria is thought to play an important role in intestinal metabolism. At the same time, there has been a decrease in other bacteria, such as Bacteroids vulgatus, which is associated with ulcerative colitis, an inflammation of the digestive tract. Changes in diet, sleep habits and physical activity may lead to these changes in gut bacteria, said co-author Vadim Gladyshev, a biologist who studies aging at Harvard University in the United States.
Zhavoronkov said the microbiome aging clock could be used as a baseline to test how fast or slowly the human gut ages, and whether things like alcohol, antibiotics, probiotics or diet all have an impact on longevity. It may also be used to compare healthy people with certain diseases, such as Alzheimer's disease, to see if their gut microbiome is out of order.
If the idea is validated, it will be used in connection with other biomarkers that scientists use to predict biological age--- including telomere length associated with aging and changes in DNA expression --- over a person's lifetime. Combining this new aging clock with other biomarkers may provide a more accurate picture of a person's true biological age and health. It may also help researchers better test whether certain interventions, including drugs and other treatments, have any effect on the aging process. "You don't have to wait until people die to experiment with longevity, " says Zhavoronkov.
Robin Knight, a computer scientist and microbiome researcher who is director of the Center for Microbiome Innovation at the University of California, San Diego, says the idea that you can predict a person's age based on a person's gut microbiome is "very reasonable" and "very interesting" to scientists studying aging. His team is analyzing 15,000 samples from the American Gut Project he founded to develop a similar age predictor.
but adds that one of the challenges in developing such a clock is that there are huge differences in bacteria in people's guts around the world. "It's important to repeat these studies in significantly different populations to determine if there are significant signs of aging in different populations," Knight said. He
it's still unclear whether changes in the gut microbiome cause people to age faster, or whether these changes are just side effects of aging. InSilico Medicine is building several machine learning-based aging clocks for use with microbiome aging clocks. "Age is an important parameter in all diseases," Zhavoronkov said. We change every second. " (Bio Valley)