The corticotrophin-releasing factor/urocortin system regulates white fat browning in mice through paracrine mechanisms.

Objectives:\ud The corticotrophin-releasing factor (CRF)/urocortin system is expressed in the adipose tissue of mammals, but its functional role in this tissue remains unknown.\ud \ud Methods:\ud Pharmacological manipulation of the activity of CRF receptors, CRF1 and CRF2, was performed in 3T3L1 white pre-adipocytes and T37i brown pre-adipocytes during in vitro differentiation. The expression of genes of the CRF/urocortin system and of markers of white and brown adipocytes was evaluated along with mitochondrial biogenesis and cellular oxygen consumption. Metabolic evaluation of corticosterone-deficient or supplemented Crhr1-null (Crhr1−/−) mice and their wild-type controls was performed alo…