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. MethodsHuman 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. ResultsCompared 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). ConclusionsBMP4 inhibits RPE proliferation and migration under oxidative stress. BMP4 is involved in inducing EMT in RPE cells.
Objective To observe the effect of Nodal on the biological behavior of retinal vascular endothelial cells (RF/6A cells) in monkeys with high glucose. MethodsRF/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. ResultsCompared 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). ConclusionsSilencing 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.