Diabetes is a well-known disease since ancient times, described 1,500 years before the birth of Christ in the Egyptian medical text, the Ebers Papyrus. Modern doctors thought they knew how it manifested itself: when the pancreas has trouble processing insulin and your blood glucose (or blood sugar) becomes too high.
But in recent years, scientists have begun to look at the gut microbiome – the menagerie of bacteria, fungi, viruses and other microbes that live in our guts and impact our health – looking for clues about how diabetes develops. A recent study in the journal Nature Medicine reports that diabetes may be caused by changes in the microbiome and that the changes a body experiences when it develops the disease may even start there.
As the rate of diabetes continues to rise in the United States, the medical world continues to search for effective treatments for this debilitating disease. Patients with type 2 diabetes, for example, experience symptoms such as fatigue, thirst, frequent urination, tingling sensations, and regular infections. If left untreated, patients with type 2 diabetes can suffer kidney damage, eye damage, heart attacks and strokes.
“We are convinced that the changes observed in the gut microbiome occur first and that diabetes develops later, not the other way around.”
For decades, doctors have treated diseases like type 2 diabetes with drugs like metformin and SGLT2 inhibitors or with insulin injections.
What this surprising new research suggests is that diabetes treatment could extend beyond the blood or pancreas, focusing instead on the microorganisms that reside in our intestines.
“Although our study is primarily hypothesis generating and cannot be considered direct evidence of causal inference, our detailed analysis (including numerous sensitivity analyses) confirms that our findings on microbial features of diabetes are unlikely due to reverse causality, that is, the pathological aspect of diabetes changes causes microbial changes,” Dr. Daniel (Dong) Wang told Salon.
The study he co-authored includes the largest and most diverse analysis of gut microbiomes ever conducted for people with type 2 diabetes (T2D), prediabetes, and healthy glycemic status. In the process, researchers at Brigham and Women’s Hospital, the Broad Institute of MIT and Harvard, and the Harvard TH Chan School of Public Health discovered both specific viruses and genetic variants in specific bacteria that correspond to the risk of T2DM.
“Therefore, we are confident that the observed changes in the gut microbiome occur first and diabetes develops later, not the other way around,” Wang said. “However, future prospective or interventional studies are needed to firmly prove the causal link.”
That said, there are some things that researchers have determined for certain. First, there are 19 phylogenetically diverse species of microorganisms living in the human intestines and associated with T2D, including enriched microorganisms. Clostridium bolteae and exhausted Butyrivibrio crossotus. Furthermore, “our study identifies phylogenetic diversity within species for strains of 27 species that explain interindividual differences in T2D risk, such as Eubacterium rectale“, explain the authors.
Perhaps the most important contribution of this article to the understanding of T2DM is that it firmly establishes that different species of microbes are linked to different levels of diabetes risk. Although scientists have not yet established exactly Why These microbes are associated with diabetes. Just knowing for sure that this is the case is an important first step. Think of it as a sort of police rally: it will be easier to determine the causes of diabetes in the future if we know what potential “criminals” look like.
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“These results lay the foundation for future mechanistic studies.”
“Different microbial strains, even within the same microbial species, are associated with different risks of diabetes,” Wang said. “Differences in this association may be explained by different genetic compositions and, therefore, different functions of the strains. »
When medical researchers apply the results of the latest study, Wang believes they will be able to use microbial characteristics as biomarkers to help patients predict their risk of developing diabetes. And that’s just the beginning.
“If future mechanistic studies can confirm that specific microbial strains are linked to diabetes risk, we could develop intervention measures, such as dietary supplements or pharmacological approaches targeting specific microbial strains to prevent and treat diabetes,” Wang said.
In recent years, research into the human gut microbiome has exploded. Scientists have discovered the gut-brain axis, in which the gut microbiome helps control our cravings and may also be linked to neurological diseases. Technologies like fecal transplants are being considered to treat diseases like ulcerative colitis and, of course, diabetes. In addition to helping us fight disease and decide what to eat, the gut microbiome is also thought to play a critical role in helping humans digest foods that their digestive tracts can’t process on their own.
“Evidence suggests that gut microbes and their human host share much of the same metabolic machinery, with the bacteria influencing food components and the amount of energy their human host is able to extract from its diet,” said the Institute of Medicine (United States) Food Forum. in 2013. “What we eat and drink, in turn, influences the microbiome, with significant implications for disease risk. This growing understanding of the role of diet in microbiome-human interactions is driving interest and investment in probiotic and prebiotic food products. means helping to build and maintain health.
In this regard, Wang suggests that the new Nature Medicine study could truly pave the way for new ways of understanding the human gut microbiota.
“These results provide the most comprehensive evidence to date for the involvement of the gut microbiome in the pathogenesis of type 2 diabetes from a population-based perspective,” Wang said. “These findings lay the foundation for future mechanistic studies. In addition, we provide a more nuanced understanding of the biology and pathogenicity of microorganisms by studying the genetic composition and characteristics of microbial strains, which brings us one step closer to causality. Our results provide evidence for the potential functional role of the gut microbiome in the pathogenesis of type 2 diabetes, and highlight the identification of taxonomic and functional biomarkers for future diagnostic applications.”
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