The key role played by gut bacteria in mediating a wide range of effects on host physiology is now starting to be understood. In this study, Johnson et al. examined whether the enzyme 11β-hydroxysteroid dehydrogenase (11β-HSD) can influence the gut bacteria and, if so, whether these effects are diet-dependent.

Using 11β-HSD1-deficient mice, they found that a lack of 11β-HSD1 had a significant effect on the abundance of certain families of gut bacteria compared with controls, and that these results were dependent on diet. Alterations were observed in the relative abundance of Prevotellaceae when mice were fed a standard chow diet, with the relative abundance of Bacteroidaceae increasing when they were fed a Western diet (high fat, cholesterol-enriched).

Although the mechanisms that underlie these findings are currently unclear, they imply that genetic effects on host–microbiome interactions can depend on diet, and that diet may be influential in some of the metabolic and inflammatory phenotypes observed in 11β-HSD1 deficiency.

Read the full article in Journal of Endocrinology 232 273–282