Alterations of the gut microbiota in high-fat diet mice is strongly linked to oxidative stress

Alterations of the gut microbiota induced by diet exert a strong influence on the development of metabolic syndrome. In this study, we prove the hypothesis that the long-term high-fat diet (HFD) may influence gut microbiota directly and/or indirectly by changing the redox state. Lipoic acid (LA), as a universal antioxidant, was used to improve the redox state. Reactive oxygen species (ROS), total antioxidant capacity (T-AOC), and malondialdehyde (MDA) were analyzed to profile oxidative stress states. PCR-denaturing gradient gel electrophoresis (DGGE) was used to describe gut flora structures, while plate count was employed for the quantitative analysis of Escherichia coli , lactobacilli, and enterococcus. The influence of redox state on the vitality of gut-derived bacteria was measured in vitro . ROS and MDA, which significantly decreased in LA mice compared with HFD mice, showed a strong positive association with E. coli and enterococcus ( P