Objective:To observe the effect of Nodal on the biological behavior of retinal vascular endothelial cells (RF/6A cells) in monkeys with high glucose.Methods:RF/6A cells were divided into normal group, mannitol group, high glucose group, high glucose combined with non-specific small interfering RNA treatment group (HG+NC group), high glucose combined with small interfering Nodal treatment group (HG+siNodal group). The transfection efficiency of siNodal was observed by real-time fluorescence quantitative PCR and western blot protein immunoblotting. The effect of Nodal on the proliferation of RF/6A cells was detected by thiazole blue colorimetry. The effect of Nodal on migration ability of RF/6A cells was detected by cell scratch assay. The effect of Nodal on the formation of RF/6A cell lumen was measured by Matrigel three-dimensional in vitro. The expression of extracellular signal phosphorylated regulated kinase 1/2 (pERK1/2) in RF/6A cells was detected by western blot protein immunoblotting. One-way analysis of variance was used to compare groups.Results:Compared with HG+NC group, Nodal protein ( F=33.469) and mRNA relative expression levels ( F=38.191) in HG+siNodal group were significantly decreased, cell proliferation was significantly decreased ( F=28.548), and cell migration ability was significantly decreased ( F=24.182). The number of cell lumen formation was significantly decreased ( F=52.643), and the differences were statistically significant ( P<0.05). Compared with HG+NC group, the relative expression of pERK1/2 protein in HG+siNodal group was significantly decreased, and the difference was statistically significant ( F=44.462, P<0.01). Conclusions:Silencing Nodal expression can inhibit proliferation, migration and tube formation of RF/6A cells induced by high glucose. It may act by inhibiting pERK1/2 expression.

Objective:To observe the effect of bone forming protein 4 (BMP4) on the proliferation and migration of human retinal pigment epithelium (RPE) cells under oxidative stress, and to preliminarily explore its effect on epithelial-mesenchymal transition (EMT) of RPE cells.Methods:Human RPE cells cultured in vitro were divided into normal group, pure 4-hydroxynonenal (HNE) group (4-HNE group), 4-HNE+NC group and 4-HNE+ small interfering BMP (siBMP4) group. The effect of 4-HNE on the proliferation of RPE cells was detected by thiazole blue colorimetry. The effects of 4-HNE and BMP4 on cell migration were determined by cell scratch test. The expression of BMP4 was detected by immunofluorescence staining, Western blot and real-time quantitative polymerase chain reaction. The transfection efficiency of siBMP4 was observed by fluorescence microscopy. Mitochondrial reactive oxygen species (MitoSOX) were detected by flow cytometry. The expression of EMT markers E-cadherin and Fibronection were detected by immunofluorescence assay. t-test was used for comparison between the two groups, and one-way analysis of variance was used for comparison between the three groups. Results:Compared with normal group, cell proliferation and migration ability of 4-HNE group were significantly enhanced, with statistical significance ( t=21.619, 24.469; P<0.05). The expression of BMP4 in cells was significantly increased, and the difference was statistically significant ( t=19.441, P<0.05). The relative expression levels of BMP4 mRNA and protein were also significantly increased, with statistical significance ( t=26.163, 37.163; P<0.05). After transfection with siBMP4 for 24 h, the transfection efficiency of BMP4 in RPE cells was>90%. Compared with 4-HNE group and 4-HNE+NC group, the relative expression levels of BMP4 protein ( F=27.241), mRNA ( F=36.943), cell mobility ( F=46.723) and MitoSOX expression levels ( F=39.721) in normal group and 4-HNE+siBMP4 group were significantly decreased. The differences were statistically significant ( P<0.05). The epithelial marker E-cadherin increased significantly, while the mesenchymal marker Fibronection decreased significantly, with statistical significance ( F= 51.722, 45.153; P<0.05). Conclusions:BMP4 inhibits RPE proliferation and migration under oxidative stress. BMP4 is involved in inducing EMT in RPE cells.