Objective
To determine the effect of thiazolidinediones (TZDs) on early retinopathy in rats with experimental diabetes.
Methods
In 40 rats, diabetic models were set up in 36 by one-off intraperitoneal injection with streptozotocin (STZ), and other 4 were in the normal control group. Twenty-four diabetic rats with the disease-duration of more than 6 months underwent intravitreous injection (with rosiglitazone or pioglitazone in 10 rats, respectively), and the rest 4 rats werenprime;t injected with drugs as the diabetic positive control group. Immunohistochemical treptomycin-avidin-biotin-complex (SABC) method, in situ hybridization of retinal vascular endothelial growth factor (VEGF) mRNA, and TdT-dUTP terminal nick-end labelling (TUNEL) were performed on the ocular paraffin section to detect the cellular apoptosis. The difference of VEGF expression and cellular apoptosis between TZDs and control group was observed and analyzed.
Results
The results of immunohistochemical staining and hybridization in situ were negative in the normal control group. The positive expression rate of VEGF was lower in rosiglitazone and pioglitazone group than which in the diabetic positive control group, and there was no obvious differences of positive expression of VEGF mRNA and cellular apoptosis between the 2 groups.
Conclusion
TZDs (rosiglitazone and pioglitazone) may inhibit the positive expression of VEGF protein in retina of STZ-induced diabetic rats to some extent, but not affect the growth of VEGF in retina.
(Chin J Ocul Fundus Dis, 2006, 22: 7-10)
Objective To study the feasibility of transplanting human saphanous vein endothelial cells to luminal surface of blood vessel prosthesis and to play a theoretical foundation for the clinical application of autologous endothelial cell transplantation. Methods Human saphanous vein endothelial cells were harvested with 0.1% collagenase and cultivated in vitro for 13.08±1.24 days. The cultures were confirmed as endothelial cells with the fourescent linked anti-Ⅷ antigen antibodies. The content of both 6-keto-PGF1α and Von Willebrand factor (vWF) in the supernatant were detected with ELISA and radioimmunoassay. The multiplied cells were lined in vitro onto the luminal surface of expanded polytetraflouroethylene (ePTFE) grafts precoated with fibrin glue and fibronectin, then cultivated again for 9 days. Results 11.46±2.69×106 of available endothelial cells could be regularly obtained, the number of endothelial cells increased 147.93±88.68 times when culture were terminated. All the cells diploid cells with a purity of 99%. The content of both 6-keto-PGF1α and vWF in the media showed no significant difference between the primary and subculture passages. The luminal surface of grafts was covered completely by a spindlelike endothelial monolayer and an even fibrin glue matrix could be seen underneath. Conclusion Endothelial cells derived from human saphanous veins might be feasible to be transplanted onto the luminal surface of ePTFE and present a potential clinical application.
Obiective
lt;brgt;To investigate the change of the activity of proliferation in cultivated Muuml;ller cells treated by advanced glycation endoproducts (AGEs), and the effect of these changes on expression of occludin in bovine retinal vascular endothelial cells (BREC).
lt;brgt;Methods
lt;brgt;The cultivated Muuml;ller cells were devided into normal growth group and cultured with AGEs group. The cultured BREC were devided into 4 groups:group 1, without any medium; group 2, with normal growth Muuml;ller cell medium (MCM); group 3,MCM treated by AGEs; group 4, without cell as the control. Enzyme-linked immuno sorbent assay was used to detect the content of occludin in the medium in the 4 groups.
lt;brgt;Results
lt;brgt;The content of expression of occludin was the most in group 2, less in group 1, and the least in group 3.
lt;brgt;Conclusion
lt;brgt;AGEs may promote the abnormal proliferation of Muuml;ller cells and inhibit the expression of occludin in BREC.
lt;brgt;(Chin J Ocul Fundus Dis, 2006, 22: 28-30)
Objective
To investigate the impact of photodynamic therapy (PDT) with verteporfin on the expression of pigment epithelial derivative factor (PEDF) mRNA and vascular endothelial growth factor (VEGF) mRNA in adult retinal pigment epithelial (RPE) cells in vitro.
Methods
The changes of cellular viability before and after PDT were assessed by methyl thiazolyl tetrazolum (MTT) colorimetric assay. Semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) was conducted to detect the expression of PEDF and VEGF mRNA in RPE cells before and after PDT.
Results
PDT caused the death of RPE cells. The cellular mortality was positively correlated with the power of photocoagulation and the concentration of verteporfin.
Conclusion
PDT could downregulate the expression of PEDF and VEGF mRNA in adult RPE cells in vitro, which may relate to the cure or relapse of subfoveal choroidal neovascular membrane after PDT.
(Chin J Ocul Fundus Dis, 2006, 22: 256-260)
Purpose
To estabalish a quantifying model of retinal neovascularization suitable for the study of pathogenesis and therapeutic intervention for the retinal neovascularization.
Methods
Sixteen one-week-old C57BL/6 mice were exposed to 75% oxygen for 5 days and then to room air and 16 mice of the same age kept in room air as controls.Ink-perfused retinal flatmount was examined to assess the oxygen-induced changes of retinal vessels.The proliferated neovascular response was quantitated by counting the nuclei of endothelial cells of new vessels extending from the retina into the vitreous in 6 mu;m sagittal cross sections. VEGF and bFGF were determined on the cross-sections after immunohistochemcal stain.
Results
Constriction and closure of the blood vessels were found under the hyperoxia condition,and dilation and proliferation were found under the relatively hypoxia status.There was a mean of 24 neovascular nuclei per cross-section in the oxygen-treated retina and less than 1 nucleus in the control group (P<0.001).VEGF stain was found ber in the inner retinal layer of oxygen-treated mouse than in that of the controls.
Conclusion
The quantifying model of retinal neovascularization may fascilitate the further researches of medical intervention and pathogenesis of retinal neovacularization.
(Chin J Ocul Fundus Dis,2000,16:213-284)
Objective To investigate the current situation and developing trend of antithrombotic function study of endothelium in vasculartissue engineering. Methods The effect of several elements onthe antithrombotic ability of endothelium, including the source of endothelium,the characteristic of the matrix materials, the cell culture methods, and the endothelium’s gene modification were analyzed. Results The normal antithrombotic function of tissue engineered vascular relied on the source ofendothelium, gene modification of seeding cells, the cell culture methods in vitro, and the characteristic of the scaffolds. Conclusion The establishment of an ideal antithrombotic functional tissue engineering vascular still requires further studies in various aspects including seeding cells, matrix materials, and cell culture methods. Gene modification of vascular endothelium, which improves the antithrombotic ability, deserves more attention.
Objective
To investigate the effect of the damage and functional change of vascular endothelial cells (VEC) on diabetic retinopathy(DR).
Methods
Circulating endothelial cell (CEC) number and plasma endothelin(ET) level were measured in 18 normal control subjects and 55 patients with diabetes mellitus (DM) consisting of 20 cases of DM with out retinopathy,20 cases of DM with-background diabetic retinopathy and 15 cases of DM with proliferative diabetic retinopathy.
Results
CEC number and plasma ET level in DM were significantly higher than those in normal subjects(Plt;0.001)respectively.With the progression of DR,CEC number was significantly elevated and plasma ET level was gradually elevated.There was significant positive correlation between CEC number and plasma ET level (r=0.738,Plt;0.001,n=55).
Conclusion
VEC damage and elevated plasma ET level induced by VEC damage may play an important role in the development and progression of DR.
(Chin J Ocul Fundus Dis,2000,16:166-168)
Objective
To investigate the effect on proliferation and apoptosis of vascular endothelial cells exposed to high glucose.
Methods
The cultured human umbilical vein endothelial cells (HUVEC) were treated with high glucose at concentrations of 10,20,30,40,50 mmol/L for 2,4,6,8,10,12,14 days,cpm value was studied by using tritium-labelled thymidine deoxyribose(3H-TdR)incorporation assay.Flow cytometry was used to detect apoptosis index,proliferation index and cell cycle.
Results
Treated with high glucose,the proliferation index and cpm were significantly reduced in a dose and time dependent manner than the control groups(Plt;0.05).The apoptosis index of HUVEC were higher compared with the control groups(Plt;0.05).The percent of the cultured cells in G1 phase in all high glucose groups were increased,the percent in S phase were largely decreased(Plt;0.05).
Conclusion
Exposed to high glucose,the apoptosis of HUVEC was accelerated and the suppressive effect of high glucose on the proliferation of HUVEC was observed.Endothelial cells were possibly arrested in G1/S checkpoint.
(Chin J Ocul Fundus Dis,2000,16:177-180)
Objective
To cultivate human retinal capillary endothelial cells (HRECs) and establish two-dimensional model of human retinal vessels in vitro.
Methods
In a fibronectincoated raising pound, HRECs were cultured by non-serum human-endothelial-cells substrate and two-dimensional model of human retinal vessels was established. Horseradish peroxidase was used to detect the permeability. Some of the vascular models were cultivated with 5 ng/ml vascular endothelial growth factor (VEGF), whose changes of permeability was compared with which of the models without cultivation with VEGF. The effect of VEGF on vascular permeability was observed.
Results
Meshy vascular structure came into being due to the confluent HRECs after 2 to 4 days. Comparatively complete two-dimensional vascular model after about 6 days. VEGF increased vascular permeability and promoted the formation of blood vessels.
Conclusion
HRECs can be cultivated successfully with human-endothelial-cells substrate; standard retinal two-dimensional vascular model in vitro can be established by using cellular raising pound and non-serum human-endothelial-cells substrate.
(Chin J Ocul Fundus Dis, 2006, 22: 110-112)
Objective
To construct specifically expressed vascular endothelial growth factor (VEGF)165 gene in retina.
Methods
Rho promoter, specifically expressed in retina, was amplified by polymerase chain reaction (PCR) from the genomic DNA of a BLAB/C rat, then it was cut with restriction enzymes and cloned into the plasmid pcDNA3.1+-VEGF165 to form recombinant plasmid pcDNA3.1+-rho-VEGF165. The correct recombinant plasmid pcDNA3.1+-rho-VEGF165 was identified by restriction enzymes and PCR, and was transferred by jetPEI into cultured human navel vein endothelial cells and human retinal pigment epithelial (RPE) cells. The expression of VEGF protein in human navel vein endothelial and RPE cells was detected by immunocytochemical staining and protraction of the growth curve of the cells.
Results
In human RPE cells, the expression of VEGF protein was more in recombinant plasmidpcDNA3.1+-rho-VEGF165 than that in plasmidpcDNA3.1+-rho-VEGF165 ; in human navel vein endothelial cells, no obvious difference of the expression of VEGF protein between recombinant plasmid pcDNA3.1+-rho-VEGF165 and plasmid pcDNA3.1+-rho-VEGF165 was found.
Conclusions
The construction of pcDNA3.1+-rho-VEGF165 carrier may provide the basic material for the study of the nosogenesis of VEGF in retinal neovascularization, and establish the foundation to set up the model of transgenic mice with VEGF specific expressing in retina.
(Chin J Ocul Fundus Dis, 2005,21:106-108)