Objective To probe a selective cultural method for bovine retinal endothelial cells (BREC) and pericytes (BRP) in vitro. Methods With the isolation of active retinal blood vessels, BREC were cultured in a fibronectin coated substrate and Dulbecco′s Modified Eagle′s Medium (DMEM) supplemented with 10% human serum and 100 ?g/ml heparin, while homogeneous cultures of retinal pericytes were obtained when isolated microvessels were seeded to uncoated dishes and grown in DMEM supplemented with 20% fetal bovine serum. BREC were identified by acetylated-low density lipoprotein (Dil-Ac-LDL) incorporation and immunohistochemical method of Von Willebrand factor, while BRP were identified by immunohistochemical method of ?-isoform of smooth-muscle actin. Results The purity of selectively cultured BREC and BRP was more than 98%, being reproducible. BREC got together around the microvessel fragments with the small-cyprinoid-like configuration at first,and could phagocytize Dil-Ac-LDL with the expression of fluorescence in cytoplasm. The expressions of Von Wllebrand factor and ?-isoform of smooth-muscle actin were positive and negative respectively in BREC, while were negative and positive respectively in BRP. Conclusion BREC and BRP with high purity can be obtained by using selective culture and coated-dishes respectively which are simple and repeatable methods.

Objective To explore a three-dimensional examination method for retinal vessels. Design Experimental study. Participants Retinal vascular digest preparations of rat. Methods After deep anaesthesia, rats were sacrificed and perfused till eyeballs pale. Then 4% paraformaldehyde was perfused for vascular internal fixation. Eyeballs were fixed in 4% paraformaldehyde for 24hr, and the retinal vessels were isolated with collagenase digest technique. After immunofluorescence staining, the retinal vessels were observed with laser scanning confocal microscope. Main Outcome Measures The digest state of retinal vascular digest preparations and three-dimensional observation of the preparations. Results Ideal complete retinal vascular digest preparations were obtained after collagenase digestion. Three-dimensional characteristics of retinal vessels can be observed with laser scanning confocal microscope. Conclusions Modified retinal vascular digest preparations combined with laser scanning confocal microscope provided us a method for retinal vascular three-dimensional structure observation.(phthalmol CHN,2006,15:138-141)

Objective To study the effects of advanced glycation end (AGEs) products induced by bovine serum albumin (BSA) on the survival and the morphology of bovine retinal endothelial cells (BREC) and pericytes (BRP). Methods BSA with the final concentration of 50 mg/ml was incubated in PBS, containing 500 mmol/L D-glucose, for 12 weeks under 37℃. AGEs-BSA was purified by Sephacryl S-300 column chromatography and was confirmed by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The concentration of AGEs-BSA was determined by the method of commassie protein assay. In order to detect the toxic effects of AGEs-BSA on cultured BREC and BRP, groups of AGEs-BSA and BSA with different concentration and untreated control were set up. Phase contrast microscope was used to observe the effect of AGEs-BSA and BSA (with the concentration of 500 ?g/ml and actuation duration of 48 hours) on morphology of BREC and BRP. Results[WTBZ] As the dosage of AGEs-BSA increased, the number of inhibited cells increased. When the concentration of AGEs-BSA was 500 ?g/ml, the inhibited BREC in AGEs-BSA group was (72.8?15.9)% of which in untreated control group, and the inhibited BRP was (64.8?9) % of which in untreated control group. AGEs-BSA with low concentration promoted the proliferation of endothelial cells, but there was no significant difference between AGEs-BSA and the control group (P=0.231). Inhibited proliferation and abnormal morphology were seen under the phase contrast microscope while the normal morphology of cells was found in BSA and control group. Conclusion AGEs-BSA with the high concentration may inhibit the growth of both BREC and BRP, which leads the loss of BRP and damage of vascular function. These results suggest that nonenzymatic glycosylation plays a major role in diabetic complications.

BackgroundHypoxia and hyperglycemia are the common causes of retinal neovascularization.In these states,H+ accumulates because of the elevated glycolysis and failure of retinal circulation,thus the retinas readily acidified. ObjectiveThe present study was to explore whether retinal acidosis independently regulates the production of vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) and whether the regulation is related to oxidative stress.Methods The retinas from 2-week-old male SD rats were cultured with explant method in DMEM modulated by NaHCO3,and culture retinas were randomly divided into pH 7.2,6.8 and 6.5 groups for 24 hours.In addition,after 24 hours of culture as above described,retinas were washed using PBS two times and then followed by again culture in DMEM with pH 7.2 for another 24 hours.Also,antioxidant was added in different pH values of DMEM for culture as above described.The retinal samples were prepared for histopathological examination.The expressions of VEGF and PEDF proteins and their mRNA in retina tissue were detected by Western blot and fluorescence quantitative polymerase chain reaction (PCR) respectively.Results The retina showed the clear structure and morphology in pH 7.2 group and pH 6.8 group,but retinal vacuoles change was seen in pH 6.5 group after culture for 24 hours.No significant difference was seen in the expressing level of VEGF mRNA in retina between normal group and pH 7.2 group( 112％ ±11％ vs 100％ ±7％ ) (P=0.55),but those in pH 6.8 group and pH 6.5 group were significant increased in comparison with pH 7.2 group( 196％ ±43％ vs 100％ ±7％ ;251％ ±29％vs 100％ ±7％ )( P＜0.05 ).The expressing level of PEDF mRNA in retina in normal group was similar to that of pH7.2 group(86％ ±19％ vs 100％ ±33％) (P=0.64),but that in pH 6.5 group was significantly higher than pH 7.2 group( 230％ ±66％ vs 100％ ±33％ ) ( P＜0.05 ).The resemble results were found in the expressions of VEGF and PEDF protein.After pH reversion,the expressing levels of VEGF mRNA were 100％ ±13％,111％ ±9％,113％ ±9％ in pH 7.2 group,pH 6.8 group and pH 6.5 group respectively without significant difference among them (F=2.51,P=0.16).The expressing levels of PEDF mRNA were 100％ ±13％,110％ ±9％,108％ ±11％in different groups ( F =0.98,P =0.43 ).Under the presence of antioxidant,the expressing level of VEGF mRNA in pH 6.5 group increased in comparison with pH 7.2 group and pH 6.8 group ( P ＜ 0.05 ).The expressing levels of PEDF mRNA were significant different among pH 7.2 group( 100±31 )％,pH 6.8 group( 282±45 )％ and pH 6.5 group(480±117)％ (F=20.73,P=0.00). Conclusions VEGF can be induced by retinal acidification alone,which may be regulated by oxidative stress.Under the retinal acidification,antioxidants promote the expression of PEDF,suggesting that oxidative stress inhibits the production of PEDF.

Objective To investigate if insulin can affect the expression of vascular endothelial growth factor (VEGF) in the retina of streptozotocin-induced diabetic rats. Methods A total of 60 male Sprague-Dawley rats were randomly divided into sodium citrate buffer control group (CIT-CON, n= 30) and STZ-induced diabetic group (STZ-DM, n=30). At the 16th week, 24 rats from CIT-CON group at random were randomly divided to group A (sodium citrate buffer control group, n = 12) and group B (sodium citrate buffer plus insulin group, n= 12). The remaining 6 rats from as CIT-CON group served as negative control. At the same time, 24 rats from STZ-DM group at random were randomly divided to group C (STZ-induced diabetic group, n= 12) and group D (STZ-induced diabetic plus insulin group, n= 12). The remaining 6 rats from STZ-DM group also served as negative control. 4 IU of insulin was injected subcutaneously to rats of group B and D. Immunohistochemistry, Western blot and Real-time polymerase chain reaction (RT-PCR) were used to measure the expression level of VEGF protein and mRNA respectively. RESULTS Insulin significantly increased the VEGF mRNA (7.71 ± 0.25 vs 5.36 ±0. 37, t test P< 0. 05) and protein expression (0. 4925 ± 0. 0122 vs 0. 4272 ± 0. 0110, t test P< 0. 05) in the retina of CIT-CON rats.However, in retina of STZ-DM rats, insulin had no effect on VEGF mRNA (8. 92±0. 27 vs 9. 05±0. 28, t test, P>0. 05) and protein expression (0. 5152±0. 0109 vs 0. 5099±0. 0100, t test P>0.05). Conclusions Insulin had no effect on VEGF expression in the retina of STZ-DM rats.

Objective To induce the experimental corneal neovascularization(CRNV) by alkali burn,and explore the methods for quantitative analysis of CRNV and observation of permeability of CRNV. Methods Thirty-six C57BL/6 mice were selected and divided into experiment group(n=30) and control group(n=6).For the experiment group,alkali burn was induced by application of filter paper with 1mol/L sodium hydroxide to the cornea for 5 s.For the control group,no intervention was conducted.Areas of CRNV were measured on day 4,7,10 and 14 after alkali burn.Histological examinations of cornea were performed with HE staining on day 3, 7,10,16 and 28 after alkali burn.On day 10,endothelial cell marker CD31 was used with immunohistochemical staining for CRNV counting,and fluorescence angiography(FA) was employed to reveal the permeability of CRNV.Corneal ulceration and hyphema were observed everyday.Results CRNV developed after alkali burn,and extincted afterwards.Axenic coneal ulceration and hyphema were frequently observed,with the incidences of 6.7% and 10.0%,respectively.Histologic changes of corneal tissues at different time points could be observed with HE staining.On day 10, CRNV could be labeled and counted with immunohistochemical staining for CD31 antibody,and the permeability of CRNV could be detected by FA. ConclusionCRNV counting with immunohistochemical staining for CD31 antibody and measurement of area of CRNV are appropriate methods for quantitative analysis of CRNV.FA is an effective method in the detection of permeability of CRNV.

Objective To observe the effects of human retinal pigment epithelium conditioned medium(HRPE-CM) on the biological characteristics of human retinal stem cells(HRSCs). Methods HRSCs were exposed to HRPE-CM and cultivated in three different cultures,including the control,epidermal growth factor(EGF) + basic fibroblast growth factor(bFGF) and HRPE-CM.Cell counting was performed to explore the effects of different culture media on the proliferation of HRSCs,and their properties as neural stem cells were further identified. Results Compared with control group,HRPE-CM significantly promoted the proliferation of HRSCs(P

AIM:To report the safty and efficiency of intravitreal injection of bevacizumab (Avastin) in patients with macular edema (ME) due to branch retinal vein occlusion (BRVO).METHODS: A consecutive series of patients with ME due to BRVO who were treated with intravitreal bevacizumab injection (2.5g/0.1L) were retrospectively studied. Patients underwent complete ophthalmoscopic examination, including Snellen visual acuity testing, optical coherence tomography (OCT) imaging, and/or flurescence angiographic testing at baseline and follow-up visits.RESULTS: There were 32 eyes of 32 consecutive patients who received at least one intravitreal bevacizumab injections (range from 1 to 3). The mean length of follow-up was 4.7 (range from 3 to 8) months. The mean visual acuity improved from 20/200- at baseline to 20/100- at 1 month and 20/100+ at 3 months and last follow-up (P＜0.01). The mean central 1mm macular thickness was 483μm at baseline and decreased to 275, 314,and 301μm at 1 month,3 months, and last follow-up (P＜0.01)respectively.No adverse side effects were observed following injections in any eyes.CONCLUSION: Intravitreal bevacizumab (Avastin) showed a marked decrease in ME secondary to BRVO, improvement in visual acuity and lack of adverse side effects.

Background Antagonists against vascular endothelial growth factor (VECF) play key roles in treating and preventing neovascular ophthalmopathy. As a novel anti-angiogenic factor, insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) might be an antagonist against VEGF in eye. Objective This study was to explore the inhibitory effect of IGFBP-rP1, a novel anti-angiogenic factor, on VEGF-induced retinal angiogenesis in vitro. Methods The retina-choroid endothelial cell line ( RF/6A ) was cultured in DMEM containing 10% fetal bovine serum. Culture cells were divided into control group(free-serum culture group) ,10mg/L VEGF culture group and different concentrations of IGFBP-rP1 (50,100,200 mg/L) +10 mg/L VEGF group. The expression of IGFBP-rP1 in the cells was detected by immunofluorescence assay. The proliferation and migration of RF/6A cells were evaluated using MTS colorimetric assay and the chemotactic motility assay, respectively. Flow cytometry was used to detect the apoptosis of RF/6A cells. Results The immunofluorescence assay RF/6A cells showed the green fluorescence in cytoplasm and red fluorescence in nuclei after cells were exposed to any concentration of IGFBP-rP1 ,but only red fluorescence was seen in nuclei in control cells. After stimulation of 10 mg/L VEGF,the proliferation value (A490) was elevated and the numbers of cell migration were increased in comparison with control group (t = -15. 191, P = 0. 000; t = -21. 274, P = 0. 000 ) , but the cellular apoptosis rate was lower than the control group (t - 10. 228, P = 0. 000 ) . After treated with various concentrations of IGFBP-rP +10% VEGF, the proliferation and migration of RF/6A cells were significantly decreased in comparison with only 10% VEGF group (F = 534. 158,P = 0. 000;F = 2742. 323,P = 0.000,respectively) ,and the inhibitory effects were gradually enhanced with the increase of IGFBP-rP1 levels (P<0. 05). The apoptosis rate of RF/6A cells in 50,100 and 200 mg/L + 10 mg/L VEGF groups increased by ( 1. 26±0. 04)% ,( 1. 50±0. 07)% and ( 1. 93±0. 27)% respectively,showing significant differences among different groups ( F = 274. 273, P = 0. 000). Conclusion IGFBP-rP1 inhibits the proliferation and activity of retina and choroid endothelial cells induced by VEGF at a concentration-independent manner. It appears to be as a novel endogenous inhibitory factor in retinal angiogenesis.

Objective To observe the influences of uncoupling protein 2 (UCP-2) rs660339 variants transfection on cell proliferation and apoptosis of human umbilical vein endothelial cell (HUVEC). Methods Two UCP-2 green fluorescent protein (GFP) lentivirus constructs were created with the rs660339 locus carried C or T (UCP-2C or UCP-2T), respectively. HUVEC were cultured after lentiviral infection of UCP-2C or UCP-2T. The expression of UCP-2C or UCP-2T was detected with real time polymerase chain reaction. Cell proliferation and cell apoptosis were compared among negative control (NC) group, UCP-2T group and UCP-2C group using CCK-8 cell viability and flow cytometry. Western blot and immunostaining were employed to examine the expression of Bcl-2 gene. Results The lentivirus constructs were successfully created.>80%of the transfected cells were found to express GFP under fluorescent microscope. The mRNA levels of UCP-2 gene were significantly increased (F=29.183, P=0.001) in the UCP-2T group and UCP-2C group. The CCK-8 assay revealed that on day two (F=15.970, P=0.004), day three (F=16.738, P=0.004), day four (F=5.414, P=0.045) post-infection, UCP-2T and UCP-2C group showed significantly greater proliferation than the NC cells. The apoptotic rate in the UCP-2T and UCP-2C group was significantly lower than NC group (F=277.138, P=0.000), and the apoptotic rate of UCP-2T was significantly lower than that of UCP-2C (P=0.003). The protein levels of Bcl-2 in the UCP-2T and UCP-2C group were significantly greater than that in the NC group (F=425.679, P=0.000), and the Bcl-2 expression of UCP-2T was greater than that of UCP-2C (P=0.002). The Bcl-2 density in the UCP-2T and UCP-2C group were greater than that in the NC group (F=11.827, P=0.008), while there was no difference between UCP-2T and UCP-2C group (P=0.404). Conclusion The variants of UCP-2 rs660339 may influence HUVEC proliferation and apoptosis, and UCP-2T showed a stronger effect of inhibiting apoptosis than UCP-2C.