Fermentation of
dietary fibers by colonic microbiota generates
short-chain fatty acids (SCFAs), e.g.,
propionic acid and
butyric acid, which have been described to have "anti-
obesity properties" by ameliorating fasting glycaemia,
body weight and
insulin tolerance in animal models. In the present study, we therefore investigate if
propionic acid and
butyric acid have effects on lipolysis, de novo lipogenesis and
glucose uptake in primary rat adipocytes. We show that both
propionic acid and
butyric acid inhibit
isoproterenol- and
adenosine deaminase-stimulated lipolysis as well as
isoproterenol-stimulated lipolysis in the presence of a
phosphodiesterase (
PDE3) inhibitor. In addition, we show that
propionic acid and
butyric acid inhibit basal and
insulin-stimulated de novo lipogenesis, which is associated with increased phosphorylation and thus inhibition of
acetyl CoA carboxylase, a rate-limiting
enzyme in
fatty acid synthesis. Furthermore, we show that
propionic acid and
butyric acid increase
insulin-stimulated
glucose uptake. To conclude, our study shows that SCFAs have effects on fat storage and mobilization as well as
glucose uptake in rat primary adipocytes. Thus, the SCFAs might contribute to healthier adipocytes and subsequently also to improved energy metabolism with for example less circulating
free fatty acids, which is beneficial in the context of
obesity and
type 2 diabetes.