Bugs on the clock

Researchers from University of Texas Southwestern Medical Center have discovered a link between the gut microbiome and the circadian mechanisms that regulate body fat storage. Their findings implicate nuclear factor interleukin-3 regulated (NFIL3) as a new target in obesity and suggest the transcription factor's expression could be reined in with a microbiome-based therapy.

Epithelial cells in the gut absorb fatty acids from food and export them into circulation as lipoproteins for storage in adipose tissue. These lipoproteins circulate in a daily pattern of high levels at night and low levels during the day, and food intake modulates the activity of transcription factors that control both circadian rhythms and fat metabolism. Previous studies had identified two potential target genes for obesity in the network controlling circadian rhythms and lipid homeostasis -- nuclear receptor subfamily 1 group D member 1 (NR1D1; Rev-ErbAα) and NR1D2 (see "Pumping Up the Metabolic REV-ERB." BioCentury Innovations (2012))...