Association of gut microbiome with fasting triglycerides, fasting insulin and obesity status in Mexican children

Background: The association of gut microbiota with obesity and its cardio-metabolic complications in paediatric populations is still controversial. Objective: We investigated the association of obesity and cardio-metabolic traits with gut microbiota on 167 and 163 children with normal weight and obesity from Mexico City and Oaxaca, Mexico. Methods: Anthropometric and biochemical traits were measured. The microbial communities were determined by high-throughput sequencing of bacterial 16S rRNA gene v3-v4 region. Results: The gut microbial community structure was associated with obesity and fasting plasma insulin (FPI) in Mexico City (P_Obesity = 0.012, P_FPI = 0.0003) and Oaxaca (P_Obesity = 0.034, P_FPI = 0.016), and with triglycerides (TG) in Oaxaca (P =.0002). The Firmicutes/Bacteroidetes ratio was positively associated with TG in Oaxaca (P =.003). Firmicutes and Bacteroidetes phyla were positively and negatively associated with obesity (Mexico City: P_Firmicutes = 0.013, P_{Bacteroidetes} = 0.009) and TG (Oaxaca: P_Firmicutes = 0.002, P_{Bacteroidetes} = 0.004). In Oaxaca, Verrucomicrobia was negatively associated with obesity (P =.004). In Mexico City, the bacterial genus Fusicatenibacter, Romboutsia, Ruminococcaceae, Ruminiclostridium, Blautia, Clostridium, Anaerostipes and Intestinibacter were associated with obesity and FPI, while in Oaxaca, Bacteroides, Alistipes and Clostridium were associated with TG. Conclusion: The gut microbial community structure in children is associated with obesity and FPI in Mexico City, and with obesity, FPI and TG in Oaxaca.