Association between blood microbiome and type 2 diabetes mellitus: A nested case-control study

Area of Science:

• Microbiome research
• Metabolic disease research
• Genomics and sequencing technologies

Background:

• Gut microbiome dysbiosis is linked to type 2 diabetes mellitus (T2DM).
• The role of the blood microbiome in T2DM development remains largely unexplored.
• This study investigates the association between blood microbial composition and T2DM incidence.

Purpose of the Study:

• To characterize the blood microbiome composition in T2DM cases versus controls.
• To identify specific microbial taxa associated with T2DM risk.
• To explore the etiological role of the blood microbiome in T2DM pathogenesis.

Main Methods:

• Prospective cohort study including 50 incident T2DM cases and 100 controls.
• Blood samples collected pre-diagnosis were analyzed for microbial composition.
• Bacterial 16S ribosomal RNA (16S rRNA) gene sequencing was performed on an Illumina MiSeq platform.

Main Results:

• No significant differences in overall blood microbiome diversity (Simpson, Chao1, Shannon indices) were observed between T2DM cases and controls.
• Increased abundance of Actinotalea, Alishewanella, Sediminibacterium, and Pseudoclavibacter genera was noted in T2DM cases.
• Lower abundance of Aquabacterium, Xanthomonas, and Pseudonocardia genera was found in T2DM cases.
• Presence of Bacteroides genus in blood was associated with a significantly decreased risk of T2DM (adjusted OR: 0.367).
• Presence of Sediminibacterium genus in blood was associated with a significantly increased risk of T2DM (adjusted OR: 14.098).

Conclusions:

• The blood microbiome may play a role in the etiology of type 2 diabetes mellitus.
• Specific bacterial genera in the blood are associated with altered T2DM risk.
• These findings support the development of microbiota-based strategies for T2DM prevention and management.