Control of cell proliferation via transduction of sPLA(2)-I activity and possible PPAR activation at the nuclear level

Pancreatic phospholipase A(2) (PLA(2)-I) stimulates U-III cells proliferati on, a rat uterine cell Line, after binding to membrane receptors, internali zation and translocation. Here, we demonstrate that during these steps of i nternalization, PLA(2)-I retains its hydrolytic activity and thus could exe rt its proliferative effect via nuclear phospholipids hydrolysis. Since fat ty acids and eicosanoids released by such activity are known to be ligands of PPAR, we study the expression of these nuclear receptors and demonstrate that, in the experimental conditions where PLA(2)-I stimulates U-III cells proliferation, PLA(2)-I also regulates PPAR expression indicating a possib le mechanism of its proliferative effect. (C) 2001 Federation of European B iochemical Societies. Published by Elsevier Science B.V. All rights reserve d.