Effect of some phytoestrogens on metabolism of rat adipocytes

The aim of this experiment was to evaluate the direct effect of genistein, daidzein and zearalenone on basal and hormone-induced lipogenesis and lipolysis in isolated rat adipocytes. In lipogenesis, daidzein and zearalenone were used at concentrations of 0.01, 0.1 and 1 mmol-L-1 and genistein at concentrations of 0.01, 0.3, 0.6 and 1 mmol-L-1 . In lipolysis, concentrations of tested com- pounds were 0.01, 0.1 and I mmol-L-1 . All tested compounds clearly inhibited basal and insulin (1 nmol-L-1 ) stimulated lipogenesis. Basal lipolysis was particularly enhanced by genistein and daidzein at its higher concentrations. The ability of zearalenone to potentiate of basal lipolysis was less marked. Epinephrine ( 1 Itmol!L-')-stimulated lipolysis was inhibited by genistein at 1 mmol-L-1 . At a concentration of 0.1 1 mmol-L-1 daidzein also augmented epinephrine-stimulated lipolysis and at its highest concentration exhibited an inhibitory effect, similar to genistein. Zearalenone reduced stimulated lipolysis, particularly at the highest concentration. © Inra/Elsevier, Paris. phytoestrogen / adipocyte metabolism Rsum ― Effet de quelques phytoestrognes sur le mtabolisme des adipocytes du rat. Le but de ce travail tait d'examiner les effets directs de la gnistine, de la daidzine et de la zaral- none sur la lipolyse et la lipogense basale et aprs stimulation par l'insuline ou l'adrnaline sur des adipocytes isols de rat. Dans le cas de la lipogense, la daidzine et la zaralnone ont t ajoutes aux concentrations de 0,01, 0,1 et 1 mmol.L-' et la gnistine aux concentrations de 0,01, 0,3, 0,6 et 1 mmol-L-'. Dans le cas de la lipogense, les concentrations testes taient les mmes pour chaque compos : 0,01, 0,1 et 1 mmol.L-1 . Tous les composs xamins rduisaient nettement la lipogense basale ou aprs stimulation par l'insuline (1 nmol!L-'). La lipolyse basale tait particulirement augmente par la gnistine et la daidzine leur plus forte concentration. L'efficacit de la za- ralnone sur la lipolyse basale tait plus faible. La lipolyse aprs stimulation par l'adrnaline (1 ltmol!L-') a t diminue par la gnistine sa plus forte concentration. La daidzine (0,1 pmol.L-1 ) augmentait aussi la lipolyse. sa plus forte concentration, la daidzine a exerc un effet contraire simi- laire celui de la gnistine. La zaralnone diminuait la lipolyse, en particulier forte concentration.