Type II diabetes, a serious metabolic condition which hampers glucose metabolism and causes a dangerous buildup of sugar in the bloodstream, appears to be affected by certain beneficial strains of bacteria in the gut, according to new research published by Oregon State University in the journal Nature Communications.
 
An in vivo study which used mouse models of type II diabetes substantiated a few probiotic strains which appeared to have a variety of positive outcomes which could be viable adjunctive treatment options for type II diabetes, pending future research.
 
“Type II diabetes is in fact a global pandemic and the number of diagnoses is expected to keep rising over the next decade,” study co-leader Andrey Morgun, associate professor of pharmaceutical sciences in the OSU College of Pharmacy, said. “The so-called ‘western diet’ – high in saturated fats and refined sugars – is one of the primary factors. But gut bacteria have an important role to play in modulating the effects of diet.”
 
While many studies have examined the effects of dysbiosis on diabetes, as well as many other health conditions, the OSU researchers used a data-driven research model called transkingdom network analysis to investigate the effects of individuals strains present in the microbiota to see if they played a part in diet-induced metabolic changes.
 
“The analysis pointed to specific microbes that potentially would affect the way a person metabolizes glucose and lipids,” Morgun said. “Even more importantly, it allowed us to make inferences about whether those effects are harmful or beneficial to the host. And we found links between those microbes and obesity.”
 
They identified four bacterial species: Lactobaccillus johnsonii, Lactobacillus gasseri, Romboutsia ilealis, and Ruminococcus gnavus.
 
“The first to microbes are considered ‘improvers’ to glucose metabolism, the other two potential ‘worseners,’” Natalia Shulzhenko, an associate professor of biomedical sciences in OSU’s Carlson College of Veterinary Medicine, and the study’s other co-leader, said. “The overall indication is that individual types of microbes and/or their interactions, and not community-level dysbiosis, are the key players in type 2 diabetes.”
 
The researchers fed mice the equivalent of a western diet and supplemented the rodents’ intake with all four of the aforementioned microbes – it was shown that the Lactobacilli improved mitochondrial health in the liver, which translated to improvements in how the host metabolized glucose and lipids. Mice receiving those Lactobacilli also had a lower fat mass index than those fed only a western diet.
 
Checking mouse results against human studies revealed that the ‘worsener’ microbes had results which were concordant with previous human studies which found a greater abundance of these bacteria types in people with obesity.
 
“We found R. ilealis to be present in more than 80% of obese patients, suggesting the microbe could be a prevalent pathobiont in overweight people,” Shulzhenko said. A pathobiont is an organism that normally has a symbiotic relationship with its host but can become disease-causing under certain circumstances.
 
“Our study reveals potential probiotic strains for treatment of type 2 diabetes and obesity as well as insights into the mechanisms of their action,” Morgun said. “That means an opportunity to develop targeted therapies rather than attempting to restore ‘healthy’ microbiota in general.”