TOPLINE:
Researchers identified diverse gut microbial features linked to type 2 diabetes (T2D), suggesting the gut microbiome's significant role in its pathogenesis and potential for diagnostic biomarkers.
METHODOLOGY:
- Researchers conducted a meta-analysis of 8117 metagenomes from 10 cohorts across the United States, Europe, Israel, and China.
- Participants (mean age, 57.9 years; 54.4% women) included 1851 patients with T2D, 2770 individuals with prediabetes, and 2277 individuals with normal blood sugar levels (normoglycemic controls).
- The diagnosis criteria for T2D and prediabetes were standardized across the cohorts.
- Researchers identified specific gut microbial species and functions that were differentially abundant between participants with T2D and prediabetes and normoglycemic controls (false discovery rate < 0.10).
TAKEAWAY:
- This study identified 19 phylogenetically diverse species associated with T2D. Two Streptococcus species, indicative of a proinflammatory condition, and Bacteroides fragilis, an immunogenic fragilysin-producing species, were notably enriched in patients with T2D.
- Prevotella copri, a common gastrointestinal microbe that can produce large amounts of branched-chain amino acids, was more abundant in the gut flora of patients with T2D.
- Within-species phylogenetic diversity observed for 27 different species was associated with interindividual differences in the risk for T2D.
- The diverse microbial signature in patients with T2D contributed to perturbations in glycolysis and butyrate fermentation pathways along with an upregulation in biosynthesis of bacterial structural components.
IN PRACTICE:
"We believe that changes in the gut microbiome cause type 2 diabetes," Fenglei Wang, PhD, of the Broad Institute of MIT and Harvard, Cambridge, and the Harvard T.H. Chan School of Public Health, Boston, said in a press release. "The changes to the microbiome may happen first, and diabetes develops later, not the other way around — although future prospective or interventional studies are needed to prove this relation firmly."
"If these microbial features are causal, we can find a way to change the microbiome and reduce type 2 diabetes risk," he added.
SOURCE:
The study, led by Zhendong Mei, PhD, of the Broad Institute and the Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, was published online in Nature Medicine.
LIMITATIONS:
The study's observational nature limits the establishment of causal relationships. The researchers were unable to control for covariates, such as diet and physical activity, that may influence the findings. The authors also acknowledge the need for additional replication cohorts to establish the generalizability of these findings.
DISCLOSURES:
This work was funded by the National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Nursing Research, National Institute on Aging, and other sources. One author declared serving on the scientific advisory boards of Zoe Nutrition, Empress Therapeutics, and Seres Therapeutics. The others declared no competing interests.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.