Objective To observe the effect of polypyramidine tract binding protein-associated splicing factor (PSF) on hydrogen peroxide (H2O2) induced apoptosis of retinal pigment epithelial (RPE) cells in vitro. Methods RPE cells were cultured and divided into a normal group, normal+H2O2 group, Vec+H2O2group, PSF+H2O2 group according to the experimental design. Overexpression of PSF in RPE cells were achieved by pEGFP-PSF plasmid transient transfection into RPE cells, then RPE cells were exposed to H2O2. The morphological changes were observed by hematoxylin-eosin (HE) staining and Live/Dead staining while the survival rate of cells was detected by MTT assay. The effect of PSF on H2O2-induced RPE apoptosis was analyzed by Cell Death Detection ELISA kit. Meanwhile, intracellular reactive oxygen species (ROS) level was detected by using DCFH-DA method. Results Overexpression of PSF could effectively alleviate the morphological changes induced by H2O2 stimulation shown by HE staining, and effectively reduce dead cells number shown by Live/Dead staining. After H2O2 stimulation, the survival rate, apoptosis rate and ROS production level in PSF overexpression group were 0.68±0.12, 0.44±0.08 and 18 616±3 382.54 respectively, showing significant difference in comparison with the vector plasmid group and normal group (P＜0.05). Conclusion PSF overexpression plays a protective role in H2O2-induced apoptosis by inhibiting the production of ROS in RPE cells.
ObjectiveTo observe RNA-Seq analysis of gene expression profiling in retinal vascular endothelial cells after anti-vascular endothecial growth factor (VEGF) treatment.MethodsRetinal vascular endothelial cells were cultured in vitro, and the logarithmic growth phase cells were used for experiments. The cells were divided into the control group and high glucose group. The cells of two groups were cultured for 5 hours with 5, 25 mmol/L glucose, respectively. And then, whole transcriptome sequencing approach was applied to the above two groups of cells through RNA-Seq. Now with biological big data obtained as a basis, to analyze the differentially expressed genes (DEGs). And through enrichment analysis to explain the differential functions of DEGs and their signal pathways.ResultsThe gene expression profiles of the two groups of cells were obtained. Through analysis, 449 DEGs were found, including 297 upregulated and 152 downregulated ones. The functions of DEGs were influenced by regulations over molecular biological process, cellular energy metabolism and protein synthesis, etc. Among these genes, ITGB1BP2, NCF1 and UNC5C were related to production of inflammation; AKR1C4, ATP1A3, CHST5, LCTL were related to energy metabolism of cells; DAB1 and PRSS55 were related to protein synthesis; SMAD9 and BMP4 were related to the metabolism of extracellular matrix. GO enrichment analysis showed that DEGs mainly act in three ways: regulating biological behavior, organizing cellular component and performing molecular function, which were mainly concentrated in the system generation of biological process part and regulation of multicellular organisms. Pathway enrichment analysis showed that gene expressions of the two cell groups were differentiated in transforming growth factor-β (TGF-β) signaling pathway, complement pathway and amino acid metabolism-related pathways have also been affected, such as tryptophan, serine and cyanide. Among them, leukocyte inhibitory factor 9 and bone morphogenetic protein 4 play a role through the TGF-β signaling pathway.ConclusionsHigh glucose affects the function of retinal vascular endothelial cells by destroying transmembrane conduction of retinal vascular endothelial cells, metabolism of extracellular matrix, and transcription and translation of proteins.
ObjectiveTo observe the protective effect of dl-3-n-Butylphthalide (NBP) on apoptosis of retinal Müller cells induced by hydrogen peroxide (H2O2).MethodsHuman retinal Müller cells cultured in vitro were divided into normal control group, model group (H2O2 group) and experimental group (H2O2+NBP group). The cells in the H2O2 group and H2O2+NBP group were cultured with 200 μmol/L H2O2 for 2 h. Then the culture solution of the H2O2 group replace with complete medium and the H2O2+NBP group replace with complete medium containing 1 μmol/L NBP. The normal control group was a conventional cultured cells. Müller cells were identified by immunofluorescence staining. Hematoxylin-eosin (HE) staining was used to observe the apoptosis morphological changes. MTT assay was used to detect the activity of of retinal Müller cells after after 24 h and 48 h of NBP intervention. Hoechst33258 staining was used to observe the apoptosis. LIVE/DEAD ® cell activity/cytotoxicity kit was used to detect cell viability. Dichlorofluorescein diacetate (DCFH-DA) + endoplasmic reticulum (ER) red fluorescent probe (ER-Tracker Red) double staining was used to observe the expression level of reactive oxygen species (ROS) in ER of cells. One-way ANOVA combined with Dunnett statistical method were used for data analysis.ResultsHE staining showed that the number of cells in H2O2+NBP group was higher than that in H2O2 group. MTT assay showed that after 24 h and 48 h of NBP intervention, the differences in cell viability between the normal control group and the H2O2 group, the H2O2 group and the H2O2+NBP group were statistically significant (t=28.96, 3.658, 47.58, 20.33; P＜0.001, 0.022). The results of Hoechst33258 showed that the nuclear nucleus of a few cells in the H2O2+NBP group was crescent-shaped and the nuclear fragmentation was reduced, and the blue fluorescence of the remaining cells was uniform. The LIVE/DEAD ® cell activity/cytotoxicity kit showed that the number of dead cells with red fluorescence in the H2O2 group increased significantly, and the number of viable cells with green fluorescence decreased significantly. In the H2O2+NBP group, the number of viable cells with green fluorescence increased, and the number of dead cells with red fluorescence decreased. The double staining results of DCFH-DA+ER-Tracker Red showed that the green fluorescence intensity of H2O2 group was significantly enhanced; the green fluorescence intensity of H2O2+NBP group was lower than that of H2O2 group.ConclusionNBP alleviates H2O2-induced apoptosis of human retinal Müller cells by inhibiting ROS production.
Objective To observe the synergistic effect of metformin and anti-vascular endothelial growth factor (VEGF) in the treatment of diabetic retinopathy. Methods This study was composed of clinical data review and in vitro cell experiment. Ten patients (12 eyes) with diabetic macular edema treated with anti-VEGF drugs were included in the study. Patients were randomly divided into the VEGF group (anti-VEGF drug therapy) and the combined treatment group (anti-VEGF drug combined with metformin). The changes of visual acuity and central retinal thickness (CRT) were compared between the two groups. As far as the in vitro experiment was concerned, vascular endothelial cells were divided into the control group (normal cells), the VEGF group (50 ng/ml VEGF), the anti-VEGF group (50 ng/ml VEGF+2.5 μg/ml of conbercept), and the combined group (50 ng/ml VEGF +2.5 μg/ml of conbercept +2.0 mmol/L of metformin). And then MTT cell viability assay, scratch assay and real-time quantitative polymerase chain reaction assay were performed to analyze the cell viability, cell migration and mRNA level of VEGFR2, protein kinase C (PKC)-α and PKC-β successively. ResultsReview of clinical trial shows that the CRT recovery rates in the combined treatment group were much higher than that in the VEGF group at 3 month after the operation, while the difference was statistically significant (t=−2.462, P＜0.05). In vitro cell experiment results showed that VEGF induction upregulated the viability and mobility of vascular endothelial cells obviously compared with control group, at the same time, the use of anti VEGF drugs can effectively reverse the trend, in contrast, combination of metformin and anti-VEGF showed a more superior effect to some extent (P＜0.05). In the VEGF group, the mRNA expression of VEGFR2, PKC-αand PKC-β were significantly increased compared with the control group (P＜0.01); while the mRNA expression of VEGFR2, PKC-αand PKC-β in the combination group decreased significantly compared with the VEGF group and the control group (P＜0.05). However, in the anti-VEGF group, the mRNA expression of VEGFR2, PKC-αand PKC-β were decreased, but has failed to reach the level of statistical learn the difference. ConclusionsThe combination of metformin and anti-VEGF drugs can reduce the CRT of diabetic retinopathy patients and inhibit the proliferation and migration of retinal vascular endothelial cells which induced by VEGF. The synergistic mechanism may be related to the inhibitory effect of metformin on the expression of VEGFR and PKC.