TGF-β1 Signaling In Fibroblasts Play An Important Role In Promoting Angiogenesis

Objective: To investigate the effect of transforming growth factor β1(TGF-β1) signaling pathways on angiogenesis promoted by fibroblasts in vitro.Methods: TGF-β1 released from Hepa1-6 cells was determined by ELISA. Fetal rat fibroblasts were devided into three groups, in which cells in DMEM/F12 group were cultured by ordinary culture medium, while those in Hepa1-6 group were cultured by conditional medium containing Hepa1-6 cell supernatant, and those in GWHepa1-6 group were cultured by conditional medium containing Hepa1-6 cell supernatant and GW788388(1u M), a TGF-β1 receptor inhibitor. The m RNA and protein levels of α-smooth muscle actin(α-SMA) and vascular endothelial growth factor A(VEGFA) in cultured fetal rat fibroblasts were determined by q PCR and immunofluorescence double staining, respectively. The angiogenesis of EA.hy 926 cells was detected by matrigel angiogenesis assay under the fibroblasts supernatant condition.Results: The levels of TGF-β1 released from Hepa1-6 cells was significantly increased as compared with DMEM/F12(P<0.01).The relative m RNA and protein levels of α-SMA and VEGFA in Hepa1-6 group fibroblasts were significantly increased as compared with DMEM/F12 group and GWHepa1-6 group(P<0.01),and the highest levels was on the 5 day. The fibroblasts supernatant conditional medium in Hepa1-6 group enhanced the angiogenesis ability of EA.hy 926 cells(P<0.01).Conclusion: TGF-β1 signaling pathways can promote the angiogenesis of EA.hy 926 cells via the levels of α-SMA and VEGFA in fibroblasts.