Objective To observe the effect of diabetic retinopathy on endothelial progenitor cells (EPCs)from peripheral blood.Methods Sixty male Wistar rats were divided into control group and diabetes group.The rats in diabetes group were induced with streptozotocin(STZ)injection for diabetic retinopathy model.Flow cytometry was used to identify and count the number of EPCs from peripheral blood at 1 week.1,3 and 6 months after injection.All eyeballs were examined by hematoxylin and eosin (HE)staining,periodic acid-Schiffs(PAS)staining of trypsin-digested retinal vessels flat preparation and transmission electron microscope.EPCs count,and the relationship between DR morphological changes and EPCs count were compared and analyzed.Results The quantity of EPCs from peripheral blood at 1 week,1,3 and 6 months after STZ injection were 25±7,28±8,39±7,43±7 cells per 200 000 monocytes respectively,which decreased compared with the control group 45±4 cells per 200 000 monocytes(F=8.933,P＜0.0 1).The quantity of EPCs was gradually increased at 1 week,1,3 and 6 months after STZ injection,accompanied with responsive pathological changes of retinal structure and vessels.The thickness of retina at 1 week and 1 month after injection were reduced slightly.The number of retinal ganglion cells reduced,with the time passing by.Endothelial cells were edema,mitochondrial was swollen,capillary basement membrane was thicken,lumen was significant stenosis,lumen occlusion and retinal artery aneurysm were observed at 6 months after STZ injection.Conclusion The number of EPCs increases gradually throughout the development of DR.

Background choroidal neovascularization (CNV) is the common reason of visual acuity impairment in high myopia patients,which usually leads to irreversible central visual impairment.Objective This study was to evaluate the clinical efficacy and safety of conbercept intravitreal injection for CNV in high myopia.Methods Fifteen high myopia patients with macular CNV diagnosed by OCT and fluorescein fundus angiography (FFA) from July 2014 to July 2015 were retrospectively analyzed.All patients were performed with intravitreal injection of conbercept 0.5 mg (0.05 ml).The best corrected visual acuity (BCVA) and central macular thickness (CMT) were examined 1 day,l week,4,8 and 12 weeks after injection.The ocular and systemic complications relating to drug were also observed.Results Fifteen eyes of 15 patients totally received 45 times of conbercept intravitreal injection.Among the total,1 eye only received 1 time of treatment,2 eyes received 2 times of treatment,12 eyes received 3 times of treatment and 1 eye received 4 times of treatments.After 12 weeks of treatment,FFA showed that fluorescein leakage disappeared in 10 eyes;fluorescein leakage area decreased in 4 eyes;fluorescein leakage was continued in 1 eye.The BCVA before treatment and at 4,8 and 12 weeks after treatment were 0.61 ±0.46,0.60±0.43,0.41±0.53 and 0.41±0.51,with significant difference among them (F=7.862,P＜0.001).The CMT before treatment and at 4,8 and 12 weeks after treatment were (280.33±14.40),(269.00±10.10),(261.93±7.80) and (259.53±6.30) μm respectively,with significant difference among them (F =32.520,P＜0.001).None of the patients conducted anterior chamber puncture because of elevated intraocular pressure,and no intraocular inflammation,vitreous hemorrhage,retinal detachment and cardiovascular disease or other serious complications occurred.Conclusions Intravitreal injection of conbercept can relieve macular edema and improve the vision.It is an effective method for the treatment of CNV associated with high myopia,but long-term follow-up observation still need to perform.

Idiopathic epiretinal membrane (iERM) is one of common fibroblast proliferative diseases in vitreoretinal interface and is significantly associated with aging.The treatment and management methods of iERM are limited, primarily including clinical following-up and vitrectomy.The time point of irreversible functional and structural damage of retina in macula is difficult to identify.Therefore, we can not predict whether surgery is safe when the symptoms of early iERM are mild, or whether surgical treatment should be postponed until metamorphopsia and vision loss occur.The formation of iERM is a process of retinal surface fibrosis, and fibrosis is a very common process in human body.Many studies on fibrosis have got a growing concern, which is helpful for us to find new treatment approch and also provides more clues of the causes of iERM.The research progress in the treatment of iERM was reviewed.

With the development of intraocular injection of anti-vascular endothelial growth factor (VEGF) drugs, early treatment of polypoidal choroidal vasculopathy (PCV) has more understanding and development.Once PCV combined with vitreous hemorrhage, treatment becomes much more difficult.The causes of vitreous hemorrhage in PCV, treatment of PCV with vitreous hemorrhage by different surgical methods, including simple vitrectomy, vitreous gas injection, intraoperative combined with vitrectomy and PDT, vitrectomy combined with CF 6, retinal pigment epithelium transplantation and other vitrectomy, as well as common operation complications, postoperative recurrence and prognosis are summarized in this article.

Objective To observe the protective effect of polypyrimidine bundle-binding proteinrelated splicing factor (PSF) over-expression on RPE cell injury induced by advanced glycation end products (AGEs).Methods The human RPE cells cultured in vitro were divided into three groups:normal control group (N group),blank control group (N + AGEs group),empty vector control group (Vec + AGEs group),and PSF high expression group (PSF + AGEs).group).RPE cells in N group were routinely cultured;RPE cells in N + AGEs group were only transfected but did not introduce any exogenous genes combined with AGEs induction;Vec +AGEs group and PSF + AGEs group were transfected with pcDNA The empty vector or pcDNA-PSF eukaryotic expression plasmid was introduced into RPE cells and induced by AGEs.Except the N group,the other 3 groups of cells were transfected accordingly,and were stimulated with 150 μg/ml AGEs for 72 h after 24 h.HE staining and Hoechst 33258 staining were used to observe the effect of high PSF expression on the morphological changes of RPE cells;ROS level detection was used to analyze the effect of PSF high expression on the ROS expression of RPE cells induced by AGEs;MTT colorimetric method was used to detect the high PSF expression Effects on the viability of RPE cells;Western blot was used to detect the effects of different time and dose of PSF on the expression of heme oxygenase 1 (HO-1).Results HE staining and Hoechst 33258 staining observation showed that the cells in group N were full in shape,the nucleus was round,the cytoplasm was rich,and the staining was uniform;the cells in N + AGEs group and Vec + AGEs group were reduced in size,the eosinophilic staining was enhanced,and the nucleus was densely densely stained.Pyrolysis and even fragmentation;the morphology of cells in the PSF + AGEs group was still full,the cytoplasm staining was more uniform,and the nucleus staining was uniform.The results of MTT colorimetry showed that high expression of PSF can effectively improve the viability of RPE cells,but this effect can be effectively antagonized by ZnPP,and the difference is statistically significant (F=33.26,P＜0.05).DCFH-DA test results showed that compared with the N + AGEs group and Vec + AGEs group,the ROS production in PSF + AGEs group decreased,the difference was statistically significant (F=1 1.94,P＜0.05).Western blot analysis showed that PSF protein upregulated HO-1 expression in a time-and dose-dependent manner.The relative expression level of HO-1 at 24,48,and 72 h after PSF protein was significantly higher than that at 0 h,and the difference was statistically significant (F=164.91,P＜0.05).The relative expression level of HO-1 under the action of 0.1,0.5,1.0,1.5,and 2.0 μg PSF protein was significantly higher than 0.0 μg,and the difference was statistically significant (F=104.82,P＜0.05).Conclusion PSF may inhibit the production of ROS by up-regulating the expression of HO-1,thus protecting the RPE cells induced by AGEs.

Objective:To observe the effect of pyrimidine bundle-binding protein-associated splicing factors (PSF) on the function of hypoxia-induced human retinal microvascular endothelial cells (hRMECs).Methods:A three-plasmid system was used to construct lentivirus (LV)-PSF. After LV-PSF infected hRMECs in vitro, the infection efficiency was measured by flow cytometry. Real-time quantitative PCR (RT-PCR) was used to detect the expression of PSF mRNA in hRMECs infected with LV-PSF. The experiment was divided into two parts, in vivo and in vitro. In vivo experiments: 20 healthy C57B/L6 mice at the age of postnatal 7 were randomly divided into normal group, oxygen-induced retinopathy (OIR) group, OIR+LV-Vec group, and OIR+LV-PSF group, each group has five mice. Mice in 3 groups were constructed with OIR models except the normal group and the mice in OIR group were not treated. The mice in the OIR + LV-Vec group and the OIR+LV-PSF group were injected with an empty vector (LV-Vec) or LV-PSF in the vitreous cavity, respectively. The effect of LV-PSF on the formation of retinal neovascularization (RNV) was observed then. In vitro experiments: hRMECs were divided into normal group, hypoxia group, vector group, and PSF high expression group. HRMECs in the normal group were cultured in vitro; hRMECs in the hypoxic group were restored to normal culture conditions for 3 h after 3 h of hypoxia stimulation; hRMECs in the vector group and PSF high expression group were infected with LV-Vec and LV-PSF for 48 h, and hRMECs were returned to normal culture conditions for 24 h with hypoxia stimulation for 3 h. The effect of PSF on cell proliferation was observed by MTT colorimetry. Cell scratch test and Transwell migration experiment were used to observe the effect of PSF on cell migration ability under hypoxia stimulation. RT-PCR was used to observe the mRNA expression of HIF-1α, VEGF and PSF in each group of cells.Results:The LV-PSF of stably expressing PSF was successfully constructed. The infection efficiency was 97% determined by flow cytometry. The level of PSF mRNA in hRMECs infected with LV-PSF was significantly increased and detected by RT-PCR. In vivo experiments: The RNV area of the mice in the OIR group and the OIR + LV-Vec group was significantly increased compared to the normal group ( t=18.31, 43.71), and the RNV area of the mice in the OIR + LV-PSF group was smaller than that in the OIR group ( t=11.30) and OIR + The LV-Vec group ( t=15.47), and the differences were statistically significant ( P<0.05). In vitro experiments: MTT colorimetry results showed that the proliferative capacity of hRMECs in the hypoxic group was significantly enhanced compared with the normal group ( t=2.57), and the proliferative capacity of hRMECs in the PSF high expression group was significantly lower than that of the normal, hypoxic, and vector groups ( t=5.26, 5.46, 3.73), the differences were statistically significant ( P<0.05). The results of cell scratch test showed that the hRMECs could be stimulated by the hypoxia stimulation for 3 hours to restore the normal condition for 24 hours or 48 hours ( t=8.35, 13.84; P<0.05). Compared with the vector group, cell migration rate in the PSF-high expression group was not significant ( t=10.99, 18.27, 9.75, 8.93, 26.94, 7.01; P<0.05). Transwell experiments showed that the number of cells stained on the microporous membrane was higher in the normal group and the vector groups, while the number of cells stained in the PSF high expression group was significantly reduced ( t=9.33, 6.15; P<0.05). The results of RT-PCR showed that the mRNA expression of HIF-1α and VEGF in hRMECs in the hypoxic and vector groups increased significantly compared with the normal group ( t=15.23, 21.09; P<0.05), but no change in the mRNA expression of PSF ( t=0.12, 2.15; P>0.05); compared with the hypoxia group and the vector group, the HIF-1α and VEGF mRNA expression in hRMECs in the PSF high expression group were significantly decreased ( t=10.18, 13.10; P<0.05), but the PSF mRNA expression increased ( t=65.00, 85.79; P<0.05). Conclusion:PSF can reduce the RNV area in OIR model mice. PSF may inhibit hypoxia-induced proliferation and migration of hRMECs through the HIF-1α/VEGF signaling pathway.

Objective To investigate the inhibitory effect oflentivirus-mediated polypyrimidine bundle binding protein-associated splicing factor (PSF) on retinal neovascularization (RNV) in mice model of oxygeninduced retinopathy (OIR).Methods One hundred and twelve 5-day-old C57BL/6J mice were randomly divided into normal control group,simple OIR model group,OIR model + lentivirus empty vector treatment group (Vec group) and OIR model + PSF lentivirus treatment group (PSF group),with 16,32,32 and 32 mice,respectively.When the mice were 7 days old,the mice in the normal control group were fed in a routine environment,and the mice in the OIR model group,Vec group and PSF group were established OIR model.The mice in the Vec group and PSF group were given an intravitreal injection of 1 μl of lentiviral vector and PSF lentivirus (titer 1 × 10~ TU/ml) at the age of 12 days.No injection was performed in the normal control group and simple OIR group.RNV was evaluated by counting the number of pre-retinal neovascular cells and analysis of non-perfusion area by immunofluorescent staining of the mouse retina.Real-time quantitative PCR was applied to detect the mRNA expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase1 (HO-1).Western blot analysis was applied to detect the protein expression ofNrf2,HO-1 and PSF.Results Of the normal control group,simple OIR model group,Vec group and PSF group,the number of pre-retinal neovascular cell nuclei were 0.00,14.36 ± 5.50,15.67 ± 4.96,8.13 ± 2.09,the non-perfusion area were 0.00％,(35.71 ± 2.81)％,(36.57 ± 4.53)％,(15.33 ± 4.75)％,respectively.The differences of the number of pre-retinal neovascular cell nuclei and non-perfusion area among 4 groups were significant (F=24.87,165.70;P＜0.05).Compared with the normal control group,there were more pre-retinal neovascular cell nucleis and larger nonperfusion area in the simple OIR model group and Vec group (P＜0.05).Compared with the simple OIR model group and Vec group,there were lower pre-retinal neovascular cell nucleis and smaller non-perfusion area in the PSF group (P＜0.05).Real-time quantitative PCR and Western blot showed that the mRNA expression of Nrf2,HO-1 (F=53.66,83.54) and protein expression ofNrf2,HO-1 and PSF (F=58.38,52.69,24.79) among 4 groups were significant (P＜0.05).The rnRNA expression ofNrf2,HO-1 and protein expression of Nrf2,HO-1 and PSF in the simple OIR model group and Vec group decreased significantly than those in the normal control group (P＜0.05).The mRNA expression ofNrf2,HO-1 and protein expression ofNrf2,HO-1 and PSF in the PSF group were increased significantly than those in the simple OIR model group and Vec group (P＜0.05).model group and Vec group (P＜0.05).Conclusion Intravitreal injection of lentivirus-mediated PSF inhibits RNV in mice model of OIR possibly through up-regulating the expression of Nrf2 and HO-1.

Objective:To observe the effects of p21 activated kinase 4 (PAK4) on the mitochondrial function and biological behavior in retinal vascular endothelial cells.Methods:The experimental study was divided into two parts: in vivo animal experiment and in vitro cell experiment. In vivo animal experiments: 12 healthy C57BL/6J male mice were randomly divided into normal control group and diabetes group, with 6 mice in each group. Diabetes mice were induced by streptozotocin to establish diabetes model. Eight weeks after modeling, quantitative real-time polymerase chain reaction and Western blots were performed to detect the expression of PAK4 in diabetic retinas. In vitro cell experiments: the human retinal microvascular endothelial cells (hRMEC) were divided into three groups: conventional cultured cells group (N group), empty vector transfected (Vector group); pcDNA-PAK4 eukaryotic expression plasmid transfected group (PAK4 group). WB and qPCR were used to detect transfection efficiency, while scratching assay, cell scratch test was used to detect cell migration in hRMEC of each group. In vitro white blood cell adhesion experiment combined with 4 ', 6-diamino-2-phenylindole staining was used to detect the number of white blood cells adhering to hRMEC in each group. The Seahorse XFe96 cell energy metabolism analyzer measures intracellular mitochondrial basal respiration, adenosine triphosphate (ATP) production, maximum respiration, and reserve respiration capacity. The t-test was used for comparison between the two groups. Single factor analysis of variance was used for comparison among the three groups. Results:In vivo animal experiments: compared with normal control group, the relative expression levels of PAK4 mRNA and protein in retina of diabetic mice were significantly increased, with statistical significance ( t=25.372, 22.419, 25.372; P<0.05). In vitro cell experiment: compared with the N group and Vector group, the PAK4 protein, mRNA relative expression and cell mobility in the hRMEC of PAK4 group were significantly increased, with statistical significance ( F=36.821, 38.692, 29.421; P<0.05). Flow cytometry showed that the adhesion number of leukocytes on hRMEC in PAK4 group was significantly increased, and the difference was statistically significant ( F=39.649, P<0.01). Mitochondrial pressure measurement results showed that the capacity of mitochondrial basic respiration, ATP production, maximum respiration and reserve respiration in hRMEC in PAK4 group was significantly decreased, with statistical significance ( F=27.472, 22.315, 31.147, 27.472; P<0.05). Conclusion:Over-expression of PAK4 impairs mitochondrial function and significantly promotes leukocyte adhesion and migration in retinal vascular endothelial cells.

Objective:To observe the effect of metformin (Met) on inflammatory bodies and focal death in human retinal microvascular endothelial cells (hRMEC) in diabetes mellitus (DM) microenvironment.Methods:Experimental research was divided into in vivo animal experiment and in vitro cell experiment. In vivo animal experiments: 9 healthy C57BL/6J male mice were randomly divided into DM group, normal control group, and DM+Met group, with 3 mice in each group. DM group and DM+Met group mice were induced by streptozotocin to establish DM model, and DM+Met group was given Met 400 mg/ (kg · d) intervention. Eight weeks after modeling, the expression of NLRP3, cleaved-membrane perforating protein D (GSDMD) and cleaved-Caspase-1 in the retina of mice in the normal control group, DM group and DM+Met group were observed by immunohistochemical staining. In vitro cell experiments: hRMEC was divided into conventional culture cell group (N group), advanced glycation end products (AGE) group, and AGE+Met group. Joining the AGE, AGE+Met groups cells were induced by 150 μg/ml of glycation end products, and 2.0 mmol/L Met was added to the AGE+Met group. Pyroptosis was detected by flow cytometry; 2' ,7'-dichlorofluorescein diacetate (DCFH-DA) fluorescent probe was used to detect the expression of reactive oxygen species (ROS) in cells of each group. Real-time fluorescence quantitative polymerase chain reaction and Western blot were used to detect the relative mRNA and protein expression levels of NLRP3, cleaved-GSDMD, cleaved-Caspase-1 in each group of cells. Single factor analysis of variance was used for comparison among the three groups.Results:In vivo animal experiments: compared with the DM group, the expression of NLRP3, cleaved-GSDMD, and cleaved-Caspase-1 in the retina of normal control group and DM+Met group mice was significantly reduced, with significant difference among the 3 groups ( F=43.478, 36.643, 24.464; P<0.01). In vitro cell experiment and flow cytometry showed that the pyroptosis rate of AGE group was significantly higher than that of N group and AGE+Met group ( F=32.598, P<0.01). The DCFH-DA detection results showed that the intracellular ROS levels in the N group and AGE+Met group were significantly lower than those in the AGE group, with the significant difference ( F=47.267, P<0.01). The mRNA ( F=51.563, 32.192, 44.473; P<0.01) and protein levels ( F=63.372, 54.463, 48.412; P<0.01) of NLRP3, cleaved-GSDMD, and cleaved-Caspase-1 in hRMEC of the AGE+Met group were significantly reduced compared to the N group. Conclusion:Met can down regulate the expression of NLRP3 inflammatory body related factors in hRMEC and inhibit pyroptosis.

RAS, a member of the small GTPase family, functions as a binary switch by shifting between inactive GDP-loaded and active GTP-loaded state. RAS gain-of-function mutations are one of the leading causes in human oncogenesis, accounting for ∼19% of the global cancer burden. As a well-recognized target in malignancy, RAS has been intensively studied in the past decades. Despite the sustained efforts, many failures occurred in the earlier exploration and resulted in an 'undruggable' feature of RAS proteins. Phosphorylation at several residues has been recently determined as regulators for wild-type and mutated RAS proteins. Therefore, the development of RAS inhibitors directly targeting the RAS mutants or towards upstream regulatory kinases supplies a novel direction for tackling the anti-RAS difficulties. A better understanding of RAS phosphorylation can contribute to future therapeutic strategies. In this review, we comprehensively summarized the current advances in RAS phosphorylation and provided mechanistic insights into the signaling transduction of associated pathways. Importantly, the preclinical and clinical success in developing anti-RAS drugs targeting the upstream kinases and potential directions of harnessing allostery to target RAS phosphorylation sites were also discussed.