By Jonathan Springston, Editor, AHC Media
Researchers who were trying to determine if microbiota encroachment might correlate with metabolic syndrome in humans found a correlation between the development of metabolic diseases, especially type 2 diabetes, and the penetration of bacteria into the mucus lining of the colon, according to a new study published this week.
“Mucoid structures that coat the epithelium play an essential role in keeping the intestinal microbiota at a safe distance from host cells,” the authors wrote. “Encroachment of bacteria into the normally almost-sterile inner mucus layer has been observed in inflammatory bowel disease and in mouse models of colitis. Moreover, such microbiota encroachment has also been observed in mouse models of metabolic syndrome, which are associated low-grade intestinal inflammation.”
Researchers examined a group of patients at the Veteran’s Administration Hospital in Atlanta, each of whom were at least 21 years of age and whom exhibited no health problems other than diabetes and were presenting for a colonoscopy. Investigators interviewed each subject about their diabetes history and inquired about gastrointestinal complaints. During colonoscopy procedures, the researchers gathered and analyzed two mucosal biopsies from the left colon.
The authors hypothesized that gut microbiota invading host cells of the mucus-lined covering of the intestinal tract can create chronic inflammation that upsets the normal insulin operation, which can promote type 2 diabetes. After their investigation, the authors concluded that “microbiota encroachment is a feature of insulin resistance-associated dysglycemia in humans.”
“Alterations in bacteria have been associated with metabolic diseases, including obesity and type 2 diabetes, but mechanisms remain elusive,” Andrew Gewirtz, professor in the Institute for Biomedical Sciences at Georgia State University and a study co-author, said in a statement. “Previous studies in mice have indicated that bacteria that are able to encroach upon the epithelium might be able to promote inflammation that drives metabolic diseases, and now we’ve shown that this is also a feature of metabolic disease in humans, specifically type 2 diabetics who are exhibiting microbiota encroachment.”
Researchers noted they are conducting follow-up studies to better determine this correlation and to discover ways to prevent this bacteria invasion. Still, outside observers see promise in these results.
“The data are impressive and may have opened a new field of investigation in metabolic function and type 2 diabetes,” Samuel Klein, MD, chief of the Division of Geriatrics and Nutritional Science at the Washington University School of Medicine Diabetes Research Center, said in a statement.
In the June 30 issue of Internal Medicine Alert, Joseph Scherger, MD, writes about a study that posits a very low carbohydrate ketogenic diet is superior to the plate method diet recommended by the American Diabetes Association for controlling and reversing type 2 diabetes. Scherger concurs with the growing consensus that diet plays a crucial role in the prevention of many diseases, including diabetes.
“When blood sugar is derived from fat and protein, the blood sugar level is steady throughout the day and night, and serum insulin is very low,” Scherger writes. “It is becoming clear that insulin resistance, prediabetes, and type 2 diabetes are a stress response from eating excessive carbohydrates.”
For more evidence-based summaries of the latest research in internal medicine, be sure to check out other issues of Internal Medicine Alert.