Evidence for a novel regulatory pathway activated by (carba)prostacyclin in preadipose and adipose cells

Prostacyclin, one of the major prostanoids generated in adipose tissue, has been previously described as an autocrine/paracrine adipogenic effector, acting, in preadipose cells, by means of cAMP and free Ca2+ as cell surface receptor-mediated messengers. The present study presents evidence for the first time that its stable analogue, carbaprostacyclin, is unique among prostanoids in regulating the expression of two differentiation-dependent genes in preadipose and adipose cells in a way distinct from that elicited by its cell surface receptor. This regulation is likely mediated by some member(s) of the peroxisome proliferator-activated receptor family and suggests that prostacyclin behaves as an intracrine effector of adipose cell differentiation.