Gut Microbiota Alterations Associated with Obesity in Adolescents with Type 1 Diabetes
Overview
This pilot study identified distinct gut microbiome and microbial metabolite profiles in obese versus lean adolescents with type 1 diabetes (T1D). Key differences included altered bacterial community composition, increased Prevotella to Bacteroides ratio, and elevated stool short-chain fatty acids (SCFAs) in the obese group.
Background
Obesity is increasingly prevalent among youth with T1D and is linked to worsened insulin sensitivity, increased insulin requirements, and higher risk of complications. The gut microbiome influences both T1D development and obesity, but the combined microbiome profile in obese youth with T1D remains unclear. Prior studies have shown gut dysbiosis in T1D and distinct microbiome changes in obesity without diabetes. Understanding microbiome alterations in obese T1D youth may reveal therapeutic targets.
Data Highlights
Parameter
Lean T1D (n=27)
Obese T1D (n=21)
Significance
Age (years)
15.3 ± 2.2
15.3 ± 2.2
NS
HbA1c (%)
7.8 ± 1.3
7.8 ± 1.3
NS
Diabetes duration (years)
5.1 ± 4.4
5.1 ± 4.4
NS
Female (%)
42.0%
42.0%
NS
β-diversity (microbial community)
Significant difference by BMI group
P = .013
Prevotella to Bacteroides ratio
Lower
Higher
P = .0058
Stool SCFA levels
Lower
Higher
P < .05
Key Findings
Significant differences in gut bacterial community composition (β-diversity) were observed between lean and obese T1D youth (P = .013).
Obese T1D adolescents had a higher Prevotella to Bacteroides ratio compared to lean counterparts (P = .0058).
Prevotella copri and other taxa were more abundant in the obese group.
Functional microbial profiling revealed upregulated branched-chain amino acid (BCAA) biosynthesis pathways in obese youth, while lean youth showed upregulation of BCAA degradation, tyrosine metabolism, and secondary bile acid biosynthesis.
Stool short-chain fatty acids (SCFAs) were elevated in obese versus lean T1D adolescents (P < .05 for all SCFAs measured).
Clinical Implications
These findings suggest that obesity in youth with T1D is associated with distinct gut microbiome signatures and metabolite profiles, including increased SCFAs and altered amino acid and bile acid metabolism. Targeting the gut microbiome may represent a novel therapeutic approach to manage obesity and potentially reduce diabetes-related complications in this population.
Conclusion
The study identifies a unique gut microbiome and metabolite signature linked to obesity in adolescents with T1D, highlighting the potential for microbiome-targeted interventions to improve metabolic outcomes in this high-risk group.
References
Alterations in Gut Microbiota Linked to Obesity in Adolescents with Type 1 Diabetes, 2024
by Heba M Ismail, Dimuthu Perera, Rabindra Mandal, Linda A DiMeglio, Carmella Evans-Molina, Tamara Hannon, Joseph Petrosino, Sara Javornik Cregeen, Nathan W Schmidt
