"Portal vein-enriched metabolites as intermediate regulators of the gut microbiome in insulin resistance"
We are all hosts to our microbiome, and thus, we are all subject to their metabolic byproducts which in turn, serve our bacteria and enable them to manipulate their hosts. In this case, microbial metabolites that contribute to insulin resistance were identified:
"Diet and obesity contribute to insulin resistance and type 2 diabetes, in part via the gut microbiome. To explore the role of gut-derived metabolites in this process, we assessed portal/peripheral blood metabolites in mice with different risks of obesity/diabetes, challenged with a high-fat diet (HFD) + antibiotics. In diabetes/obesity-prone C57BL/6J mice, 111 metabolites were portally enriched and 74 were peripherally enriched, many of which differed in metabolic-syndrome-resistant 129S1/129S6 mice."
"The gut microbiome is a major contributor to health and disease through multiple mechanisms, including effects on intestinal integrity, regulation of inflammation, and contributions to circu-lating metabolites through the actions of the bacteria on dietary constituents.34–36 These factors can be modulated by the nature of the diet, composition of the microbiome, and host genetics. The portal vein drains blood from the intestine,27 making the liver the first site of impact of gut microbiota-derived metabolites. Here, we have explored this interaction by assessing portal versus peripheral serum metabolites in strains of mice with different propensities to metabolic syndrome on chow and HFDs, as well as metabolic syndrome-prone B6J mice on HFD without/with antibiotic treatment. We show that the metabolomic profile in portal blood is quantitatively and qualitatively distinct from that in cardiac blood and that this relationship changes differently in different strains of mice and in response to diet/antibiotics. More importantly, these differences can be used to identify metabolites that have potent effects on hepatic insulin action and gene expression."