Gut microbiota and its possible relationship with metabolic syndrome and type-2 diabetes mellitus in Mexican pediatric subjects

Abstract

Nearly a decade ago, transfer of gut microbiota in mice models revealed the possibility that gut microbial dysbiosis may be involved in the onset of cardiometabolic abnormalities characteristic of metabolic syndrome (MetS), a medical condition that has been correlated with the progression of relevant and irreversible maladies such as cardiovascular diseases and type-2 diabetes mellitus (T2DM), which have shown to be major public health concerns in a worldwide level. Conventional techniques have demonstrated to be insufficient to study the taxonomical composition and completely understand the functional potential of these microscopic communities, which may help to elucidate gut microbiome – host interactions possibly related with human’s health. Moreover, the advent of next-generation sequencing (NGS) technologies has opened up the opportunity to know more about these interactions. Nowadays, gut microbiota in adults has been widely studied compared to that in children. Due to this, shotgun metagenomics was used in the present work to study the taxonomy and functional potential of gut microbiota in Mexican pediatric subjects with MetS and T2DM. As relevant findings, taxonomic studies showed a significant increase in facultative anaerobes (mainly belonging to the Enterobacteriaceae family and lactic acid bacteria) and a decreased abundance of strict obligate anaerobes (nitrite-producers belonging to the Actinobacteria phylum and butyrate-producers belonging to the Erysipelatoclostridium genera) within the MetS and T2DM study groups compared with the healthy individuals. Interestingly, some viral communities also showed to be strongly correlated positively (Jiaodavirus genus and Inoviridae family) and negatively (Retroviridae and Rudiviridae families) with proinflammatory activity, being one of the first studies revealing possible significance of gut virome in school-age children with these metabolic conditions. Moreover, functional potential analysis showed a significant increase in gut microbial nitrogen metabolism within the MetS and T2DM study groups compared with the healthy individuals and specific genes related with aerobic respiration, denitrification pathway, and production of pathogen-associated molecular patterns were also overrepresented in these studied groups, opening up the possibility to be one step ahead in revealing possible associations between gut microbiome and metabolic disparities related with MetS. As future perspectives, studying children will improve our understanding regarding gut microbial – host interactions, helping to develop effective microbiome-based interventions that may complement existing medical treatments to delay or impede the onset of metabolic disorders since early stages of life.