Abstract：Forkhead box transcription factor O1(FoxO1) plays a critical role in cell proliferation and differentiation in mammals. To interpret effects of the phosphorylation of FoxO1(p-FoxO1) on pig preadipocytes adipogenesis and it's underlying molecular mechanism, pig preadipocytes were cultured. After treated with wortmannin(WM), differentiation state of pig preadipocyte was detected by Oil Red O staining and the expression level of FoxO1 and adipocyte differentiation marker gene were analysed by qRT-PCR and Western blot. The results findings showed that as differentiation proceeded, FoxO1 mRNA, protein and p-FoxO1 protein were all increased. After the pig preadipocytes were treated with WM for 5 days, FoxO1 protein was notably increased(P<0.05), but p-FoxO1 protein was decreased significantly, meanwhile FoxO1 mRNA was not much changed. Oil red O staining showed that adipocytes differentiation was attenuated and adipocyte markers, such as PPARγ and C/EBPα, were remarkably lowered(P<0.05). Taken together, our data demonstrate WM decreases FoxO1 phosphorylation level and suppresses adipogenesis by reducing PPARγ and C/EBPα mRNA. Differentiation of pig preadipocytes is inhibited by dephosphorylation of FoxO1.
