Gut Microbiome Biomarkers in Adolescent Obesity: a Regional Study

ABSTRACT Purpose This study aimed to characterize the gut microbiota in obese Shenzhen adolescents, and evaluate the influence of gender on BMI-related differences in the gut microbiome. Methods Physical examinations, blood pressure measurement, serological assay, and body composition evaluation were conducted on two-hundred and five adolescents from Shenzhen. Fecal microbiome composition was profiled via 16S rRNA gene sequencing. A Random Forest (RF) classifier model was built to distinguish the BMI categories based on the gut bacterial composition. Results Fifty-six taxa consisting mainly of Firmicutes were identified that having significant associations with BMI; two OTUs belonging to Ruminococcaceae and one belonging to Lachnospiraceae had relatively strong positive correlations with body fate rate, waistline, and most of serum biochemical parameters. Based on the 56 BMI-associated OTUs, the RF model showed a robust classification accuracy (AUC 0.96) for predicting the obese phenotype. Gender-specific differences in the gut microbiome composition was obtained, and a lower relative abundance of Odoribacter was particularly found in obese boys. Functional analysis revealed a deficiency in bacterial gene contents related to PPAR signaling pathway in obese subjects for both genders; significantly lower levels of adipocytokine signaling pathway and ethylbenzene degradation were particularly detected in obese girls. Conclusions This study revealed unique features of gut microbiome in terms of microbial composition and metabolic functions in obese Shenzhen adolescents. The effect of geographical location, age and gender on the gut microbiome should be carefully considered in case–control studies.