Intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) drugs, including monoclonal antibodies (such as bevacizumab and ranibizumab) and fusion protein agents (such as aflibercept and conbercept) have been proven to be effective in the treatment of wet age-related macular degeneration (wAMD). However, there are still some patients with poor efficacy, such as no response to initial treatment or poor response, and even relapse during the course of treatment. In view of the different targets and molecular characteristics of anti-VEGF drugs, the switch of anti-VEGF drugs and the adjustment of delivery pattern, dosages and intervals have been the strategies to cope with the poor efficacy in clinic. However, there are some differences in the results of current studies. Overall, the recovery of retinal anatomical outcome achieves more benefits, and it is relatively difficult to improve visual acuity. To determine which regimen would get the biggest benefits, a large number of randomized controlled clinical trials and long study period will be needed.
ObjectiveTo observe RNA-Seq analysis of gene expression profiling in human retinal vascular endothelial cells after anti-vascular endothecial growth factor (VEGF) treatment.MethodsCultured the retinal vascular endothelial cells in vitro and logarithmic growth phase cells were used for experiments. The cells were divided into VEGF group and VEGF combined with anti-VEGF drugs group. The VEGF group cells were treated with 50 ng/ml VEGF for 72 h to simulate the high VEGF survival conditions of vascular endothelial cells in diabetic retinopathy. VEGF combined with anti-VEGF drug group cells was treated with 50 ng/ml VEGF and 2.5 μg/ml anti-VEGF drugs for 72 h to imitate the microenvironment of cells following the anti-VEGF drugs treatment, and 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, 328 DEGs were found, including 194 upregulated and 133 downregulated ones. The functions of DEGs were influenced by regulations over molecular biological process, cellular energy metabolism and protein synthesis, etc. Among these genes, SI,PRX and HPGD were related to protein synthesis, BIRCT to cellular apoptosis, and ABLIM1 and CRB2 to retinal development, and ABCG1, ABCA9 and ABCA12 were associated with the cholesterol of macrophage and the transfer of phospholipid. GO enrichment analysis showed that DEGs mainly act in three ways: regulating biological behavior, organizing cellular component and performing molecular function. Pathway enrichment analysis showed that gene expressions of the two cell groups were differentiated in ECM receptor pathway, and Notch, mitogen-activated protein kinase, transforming growth factor (TGF)-β and Wnt signal pathways. Among them, the gene expression in TGF-β signal pathway attracts most attention, where the DEGs, such as CAMK2B, COL3A1, CYGB, PTGER2 and HS6ST2, among others, were closely related to fibrosis process.ConclusionThe anti-VEGF drugs may enhance the expression of CAMK2B, COL3A1, CYGB, PTGER2 and others genes related to TGF-β signal pathway and aggravate retinal fibrosis disease.
ObjectiveTo construct the connective tissue growth factor (CTGF) recombinant interference vector (shRNA) and observe its inhibitory effect on the expression of endogenous CTGF in retinal vascular endothelial cells. Methods The human CTGF shRNA was constructed and the high-titer CTGF shRNA lentivirus particles was acquired via three-plasmid lentivirus packaging system to infect retinal vascular endothelial cells. The optimal multiplicity and onset time of lentivirus infection were identified by tracing down the red florescent protein in interference vector. The cells were classified into three groups: blank control group, infection control group and CTGF knockdown group. The differences in cells migrating ability was observed through Transwell allay. The mRNA and protein expression of CTGF, fibronectin, α-smooth muscle actin (α-SMA) and collagen Ⅰ (Col Ⅰ) were quantified through real-time PCR testing and Western blot system. Data between the three groups were examined via one-way analysis of variance. ResultsThe result showed that an optimal multiplicity of 20 and onset time of 72 hours were the requirements to optimize lentivirus infection. Transwell allay result showed a contrast in the number of migrated cells in the CTGF knockdown group and that in the blank control group and infection control group (F=20.64, P=0.002). Real-time PCR testing showed a contrast in related gene expression (CTGF, fibronectin, α-SMA and Col Ⅰ) in the CTGF knocked-down group and that in the blank control group and infection control group (F=128.83, 124.44, 144.76, 1 374.44; P=0.000, 0.000, 0.000, 0.000). Western blot system showed the statistical significance of the contrasted number of related protein expression (CTGF, fibronectin, α-SMA and Col Ⅰ) in the knockdown group and that in the blank control group (F=22.55, 41.60, 25.73, 161.68; P=0.002, 0.000, 0.001, 0.000). ConclusionThe success in producing CTGF shRNA lentivirus particle suggests that CTGF shRNA lentivirus can effectively knock down CTGF expression.
ObjectiveTo observe the changes of follistatin-like protein 1 (FSTL1) in serum of patients with proliferative diabetic retinopathy (PDR).MethodsTwenty PDR patients confirmed by clinical examination and 20 normal people were included in the study. Human retinal vascular endothelial cells (HRCEC) were divided into HRCEC blank control group, 3 h hypoxia group, 6 h hypoxia group. Human umbilical vein endothelial cell (HUVEC) were divided into HUVEC blank control group, 3h hypoxia group, 6h hypoxia group. Real-time quantitative PCR (RT-PCR) and ELISA were used to determine the expression of FSTL1, TGF-β, VEGF, connective tissue growth factor (CTGF) mRNA and protein in peripheral blood and cells of all groups from all subjects.ResultsThe expressions of FSTL1, TGF-β1, CTGF, VEGF mRNA in blood samples of patients with PDR were 1.79±0.58, 0.97±0.21, 1.85±0.69 and 1.38±0.44. The expressions of FSTL1, TGF-β1 protein were 1.19±0.50, 0.71±0.24 ng/ml and 734.03±116.45, 649.36±44.23 ng/L. Compared with normal people, the differences were statistically significant (tmRNA=0.90, 0.21, 2.85, 1.77; P=0.00, 0.00, 0.04, 0.02. tprotein=1.88, 7.68; P=0.00, 0.02). The cell viability of HRCEC cells in the 3 h hypoxia group and the 6 h hypoxia group were 0.66±0.05 and 0.64±0.04, respectively. Compared with the blank control group, the difference was statistically significant (F=13.02, P=0.00). The cell viability of HUVEC cells in the 3 h hypoxia group and the 6 h hypoxia group were 0.63±0.06 and 0.68±0.06, respectively. Compared with the blank control group, the difference was statistically significant (F=26.52, P=0.00). Comparison of FSTL1, TGF-β1, CTGF, and VEGF mRNA expression in HRCEC blank control group and 3 h hypoxia group, the differences were statistically significant (F=14.75, 44.93, 85.54, 6.23; P=0.01, 0.00, 0.00, 0.03). Compared with the HRCEC blank control and 3 h hypoxia group, the expressions of FSTL1 and TGF-β1 protein were statistically significant (P＜0.05). There was a statistically significant difference in TGF-β1 protein expression in the hypoxic 6 h group (P=0.03) and no significant difference in FSTL1 protein expression (P=0.68). Comparison of FSTL1, TGF-β1, CTGF, and VEGF mRNA expression in HUVEC blank control group and 3h hypoxia group, the differences were statistically significant (F=19.08, 25.12, 22.89, 13.07; P=0.00, 0.00, 0.00, 0.01). Immunofluorescence staining results showed that FSTL1, TGF-β1, CTGF, and VEGF proteins were positively expressed in cells in the 3h hypoxia and 6h hypoxia groups.ConclusionThe expression of FSTL1 gene and protein in serum of PDR patients was significantly higher than that of normal people.