Age and Dietary Fat Result in Larger Inflammatory Populations of Gut Microbes

This study investigated the short-term responses of the gut microbiota composition to diets with different fat contents. Experimental animals were fed either a a normal diet (ND) or a high-fat diet (HFD) for 20 weeks and the microbial composition was evaluated at 10 and 20 weeks. In agreement with previous studies, body weight and the expression of colonic cytokines increased with higher dietary fat content. The diversity of the gut microbiota was significantly influenced by both age and diet, and two variable showed significant interactions. At the phylum level, the proportion of Actinobacteria was significantly associated with dietary fat content, while the proportions of Firmicutes and Bacteroidetes were strongly associated with age. In the present study, a HFD significantly elevated the proportions of the phylum Actinobacteria and the class Actinobacteria_c in a positive association with body weight, which have also been shown to be increased in obese subjects and patients with type 2 diabetes. A growing body of evidence suggests that a HFD increases gut permeability and endotoxemia, resulting in low-grade inflammation and impairment of the gut barrier. Given that bacteria in the phylum Actinobacteria are known as mucin-degrading bacteria, abundant Actinobacteria might be associated with gut barrier impairment induced by a HFD. Indeed, we observed that Actinobacteria was inversely related with tight junction proteins such as E-cadherin and positively ass...
Source: Fight Aging! - Category: Research Authors: Tags: Daily News Source Type: blogs