Genes encoding the transcription factors controlling the core circadian
oscillator (BMAL, Clock, NPAS, Per) and their regulatory targets
(Rev-erb.alpha., Rev-erb) have been found in adipose tissue. The
circadian pattern of these genes was entrained using restricted feeding.
The circadian gene expression profiles were examined in mice and in
undifferentiated and adipocyte-differentiated human adipose stem cells
following exposure to nuclear hormone receptor ligands (dexamethasone or
thiazolidinedione) or 30% fetal bovine serum. All three agents induced
the initiation of a cyclic expression profile in representative circadian
genes in the human adipose stem cells. The circadian genes studied
displayed an oscillatory expression profile, characterized by both a
zenith and nadir within a 24-28 hr phase. The circadian gene pattern has
been lengthened with use of an inhibitor of glycogen synthase kinase 3
beta. Modulation of the circadian pattern to lengthen or shorten can be
used to affect weight gain or loss, respectively.