Objective To investigate the effect of surface propertyof different polyether-ester block copolymers［poly(ethylene glycol-terephthalate)/poly(butylene terephthalate), PEGT/PBT］ on the growth of smooth muscle cells (SMCs) and endothelial cells(ECs). Methods Three kinds of copolymers were synthesized, which were 1000-T20 (group A), 1000PEGT70/PBT30 (group B) and 600PEGT70/PBT30 (group C). The water-uptake and contact angle of three polyether-ester membranes were determined. The canine aorta smooth muscle cells and external jugular vein endothelial cells were primarily harvested, subcultured, and then identified. The proliferation of SMCs and ECs on the different polyether-ester membranes were investigated. Results The water-uptake of three copolymers arranged as the sequence of group C＜group A＜group B, and contact angle as the sequence of group C＞group A＞group B, indicating group B being more hydrophilic. However, smooth musclecells andendothelial cells grew poorly on the membrane of group B after low density seeding, but proliferated well on the membranes of group A and group C. Conclusion In contrast with more hydrophilic 1000PEGT70/PBT30, moderately hydrophilic 1000-T20 and 600PEGT70/PBT30 has better compatibility with vascular cells. The above results indicate that the vascular cells can grow well on moderately hydrophilic PEGT/PBT and that PEGT/PBT can be used in vascular tissue engineering.
ObjectiveTo investigate the effects of thrombospondin-1 active fragment (TSP-1) synthetical peptide VR-10 on proliferation and migration of rhesus choroidal-retinal endothelial (RF/6A) cell and the expressions of apoptosis relative genes in RF/6A cell. MethodsThe survival rate of RF/6A cell were detected by methyl thiazolyl tetrazolium, and migration ability was measured by transwell chamber after exposure to 1.0 μg/ml TSP-1 and synthetic peptide VR-10 (0.1, 1.0, 10.0 μg/ml) for different times (6, 12, 24, 48 hours). Caspase-3 and factor associated suicide (FAS) protein levels were measured by Western blot. The mRNA level of bcl-2 and FAS ligand (FASL) were measured by reverse transcription-polymerase chain reaction (RT-PCR). ResultsThe survival rate of RF/6A cells was determined by the treatment time and concentration of TSP-1(1.0 μg/ml) and the synthetic peptide VR-10 (0.1, 1.0, 10.0 μg/ml). The lowest survival ratio of RF/6A was 78% (P < 0.001) when cells were treated by 10 μg/ml synthetic peptide VR-10 after 48 hours. TSP-1 and synthetic peptide VR-10 could inhibit migration of RF/6A cells in transwell chamber (P < 0.001). 10.0 μg/ml synthetic peptide VR-10 had the strongest effect, 1.0 μg/ml TSP-1 was the next. Migration inhibition rate was increase with the increase of the concentration of VR-10 (P < 0.001). There was no significant differences between 0.1 μg/ml and 1.0 μg/ml VR-10 (P=0.114). Western bolt showed that RF/6A cell in control group mainly expressed the 32×103 procaspase-3 forms. To 10.0 μg/ml VR-10 treated group, it showed decreased expression of procaspase-3 (32×103) and concomitant increased expression of its shorter proapoptotic forms (20×103). Compared with control group, expression of FAS peptides were significantly increased in 10.0 μg/ml VR-10 treated group. Compared with control group, expression of FasL mRNA was significantly increased in 10.0 μg/ml VR-10 treated group(t=39.365, P=0.001), but the expression of bcl-2 mRNA was decreased(t=-67.419, P=0.000). ConclusionTSP-1 and synthetic peptide VR-10 had the ability to inhibit proliferation and migration of endothelial cell, and also induce apoptosis by increasing FAS/FASL expression and repressing bcl-2 expression.
ObjectiveTo explore repressive effects of transthyretitin (TTR) on the growth of human retinal endothelial cells (hREC) under high glucose and hypoxia environment.MethodshRECs were divided into 8 groups, including normal glucose group (5.5 mmol/L glucose), hypoxia group, high glucose group (25.0 mmol/L glucose), high glucose and hypoxia group, normal glucose group+TTR, normal glucose and hypoxia group+TTR, high glucose group+TTR, high glucose and hypoxia group+TTR. Flow cytometry was used to analyze cellular apoptosis. The expression level of Akt, p-Akt, eNOS, Bcl-2 and Bax protein were measured by Western blot.ResultsHypoxia could induce apoptosis as the apoptosis rate of normal and hypoxia group was higher than normal group (χ2=25.360, P＜0.05), high glucose and hypoxia group was higher that high glucose group (χ2=17.400, P＜0.05). The cell apoptosis rate of high glucose and hypoxia group+TTR were increased significantly as compared with high glucose and hypoxia group (χ2=9.900, P＜0.05). There was no statistically significant difference on the cell apoptosis rate between normal group and high glucose group, normal group+TTR and normal group, high glucose group+TTR and high glucose group, normal and hypoxia group+TTR and normal and hypoxia group (P＞0.05). Western blot showed that the expression of Akt did not change significantly in all eight groups（F=2.450, P＞0.05). Compared to normal group, the expression of p-Akt, eNOS, Bcl-2 in normal and hypoxia group were decreased (t=9.406, 5.306, 4.819), and the expression of Bax (t=−4.503) was increased (P＜0.05). Compared to high glucose group, same trend was found in high glucose and hypoxia group (t=8.877, 7.723, 6.500, −14.646; P＜0.05). The expression of p-Akt in normal and hypoxia group+TTR was higher than normal and hypoxia group (t=−5.024, P＜0.05) , but there was no difference on the expression of eNOS, Bcl-2, Bax between these two groups (t=−2.235, −2.656, −0.272; P＞0.05). Compared to high glucose and hypoxia group, the expression of p-Akt and Bcl-2 in high glucose and hypoxia group+TTR were decreased (t=4.355, 4.308; P＜0.05), the expression of Bax was increased (t=−4.311, P＜0.05), and there was no difference on the expression of eNOS between these two groups (t=−1.590, P＞0.05). There was no statistically significant difference in the expression of p-Akt, eNOS, Bcl-2, Bax between high glucose group and normal group (t=−3.407, −4.228, −4.302, −2.076; P＞0.05), normal group+TTR and normal group (t=−4.245, −4.298, −2.816, −1.326; P＞0.05), high glucose group+TTR and high glucose group (t=4.016, −0.784, 0.707, −0.328; P＞0.05).ConclusionUnder high glucose and hypoxia, transthyretitin suppress the growth of hREC through Akt/Bcl-2/Bax, but not Akt/eNOS signaling pathway.
Objective To verify the effect of Evans blue dye on determining the retina blood vessel leakage． Methods Male Sprague-Dawley rats were used in this study． The VEGF induced retinal blood vessel leakage was checked with Evans blue dye． Then the bloodretina barrier breakdown of 1 week diabetic animals was quantified with Evans blue．The dye was extracted from retina by formamide and the extraction was checked with spect rophotometer． Evans blue leakage was normalized against wet or dry retina weight． Results The retinal Evans blue content of eyes treated with VEGF was remarkably higher than that of the controls (n=17 ,Plt;0．0001)． And the eyes of 1 week diabetic duration animals had more Evans blue dye than that of the normal controls (Plt;0．05)． Conclusion Evans blue dye is a sensitive tracer in quantitatively diagnosing the blood retina barrier breakdown． (Chin J Ocul Fundus Dis, 2001,17:221-223)
Objective To investigate the spatial and temporal regulation effect of VEGF on human fetal retinal vascularization and angiogenesis. Methods The posterior segmental retinas from 54 human fetuses of the 9th week to the 40th week were studied by immunohistodhemistry standing for the expressions of VEGF and PCNA. Results 1. The distribution of VEGF espression was spiking and the peaks were during the 9th-13th and around the 26th week. 2. PCNA immunoreactivity was localized in spindle cells and vascular endothelial cells. The expression level was fluctuated during the developmental process. The peaks were during the 9th-13th and around the 21st week. In these periods, the spindle cells kept proliferating and differentiating, and remodelled subsequently to form the inner side retinal vessels. From the 26th or 34th week, the PCNA immununoreactivity is fully expressed in the vascular endothelial cells of the inner and outer margin of inner nuclear layer(INL) and kept to full terms. 3. Significant positive correlation were shown between the content of VEGF in the retina and that of PCNA in spindle cells and vascular endothelial cells(r=0.736,p＜0.01). Conclusion VEGF was positively involved in modulating human fetal retinal vascularization and angiogenesis. (Chin J Ocul Fundus Dis,1999,15:12-15)
Objective To evaluate the effect of vascular endothelial cell growth factor (VEGF) antisense oligodeoxynucleotides (ASODNs) on the expression of VEGF in rats with oxygen-induced retinopathy. Methods Thirty newborn Sprague-Dawley (SD) rats were randomly divided into 3 groups:normal control group, disposal group and non-disposed group, The animal models with oxygen-induced proliferative retinopathy were established by raising the rats in hyperoxic environment. Retrobulbar injection was performed with VEGF ASODNs or normal saline on the rats in 3 groups respectively. The intraocular tissues (all the tissues except the cornea, sclera, and lens) and serum were collected, and the expressions of VEGF were determined by using competitive enzyme immunoassay.Results The expressions of VEGF in intraocular tissues of rats in disposal group were significantly lower than those in non-disposed group (P＜0.05), and there was no statistical difference between the disposal and normal control group (P＞0.05). There was no significant difference of the expressions of VEGF in serum of rats between the disposal and non-disposed group (P＞0.05), which were both lower than those in the normal control group (P＜0.05). Conclusion VEGF ASODNs could significantly inhibit the expression of VEGF in intraocular tissues. (Chin J Ocul Fundus Dis，2003，19：172-174)
Objective To evaluate which is better method zymogen or low temperature frozen in removing vascular endothelial cell so as to lay a foundation for creating a kind of brace which is not to be rejected and the same as own blood vessel. Methods Fresh and not damaged umbilical blood vessel was collected from natural labour women, human umbilical blood vessel was remove carefully from normal foetus, then was put into disinfectant at 37℃ for 24 hours. They were divided into 3 groups:normal group(NG),zymogen group(ZG) and low temperature frozen group(LG). ZG: 0.1% collagenⅡ enzyme was addedin umbilical blood vessel and closed the both sides and the vascular endothelialcell was removed in 37℃ water. LG:Umbilical blood vessel was put into liquidnitrogen for 24 hours after frozened step by step, and then it was put into 37℃ water for 30-60 s and the vascular endothelial cells were washed away by normal saline. NG:Umbilical blood vessel was kept into 4℃ Kerb’s liquid. The bacteria were culturedin each group. The samples were stained by HE,elastic fiber and collagen fiberwere observed by light and scanning electron microscope. The difference of compliance was compared. Human leukocyte antigen ABC(HLA-ABC) and HLA-DR were observed by immunohistochemical method and the expression of antigen of umbilical blood vessel was analysed. Results In LG, umbilical vascular endothelial cells were removed completely; artery showed vertical smooth muscle and vein showed elastic membrane. InZG, umbilical vascular endothelial cells were removed completely after 20 minutes;artery showed vertical smooth muscle cells and vein showed lower endothelial layer. The vascular compliance in LG was higher than that in NG, and the latter was also higher than that in ZG,but showing no significant differences (Pgt;0.05). The compliance of umbilical vein was 2-3 times as much asthat of umbilical artery.The expression of HLA-ABC and HLA-DR in LG andZG were lower than that in NG, showing significant differences (Plt;0.01). Conclusion Low temperature frozen methodand zymogen method(0.1% collagen Ⅱ enzyme for 20 min) can remove vascular endothelial cells of human umbilical blood vessel completely.Low temperature frozenmethod was better than zymogen method.
Objective To discuss the endothelial cell which was modified by exogenous anticoagulant genes contribute to the increase of antithrombosis activity of lined vascular prosthesis and the influence to other physiological functions of endothelial cells. Methods This summarized paper was made on literature review of recent years. Results The transfection of genes, including plasminogen activator (tPA, uPA, Urokinase), thrombomoduline (TM) and hirudin, etc, to endothelial cells resulted in not only the increase of antithrombosis activity of local vascular, but also the decrease of endothelial cell function in adherence and proliferation. Conclusion The increase of antithrombosis activity of lined vascular prosthesis has been done by exogenous genes. However, this technique ought to be studied, intensively.
Objective To investigate the effect of arginase (Arg) inhibitor N-ω-Hydroxy-L nor-Arginine (nor-NOHA) on high glucose cultured rhesus macaque retinal vascular endothelial cell line (RF/6A) in vitro. Methods The RF/6A cells were divided into the following 4 groups: normal control group (5.0 mmol/L of glucose, group A), high glucose group (25.0 mmol/L, group B), high glucose with 125 mg/L nor-NOHA group (group C), and high glucose with 1% DMSO group (group D). The proliferation, migration ability and angiogenic ability of RF/6A cells were measured by Methyl thiazolyl tetrazolium (MTT), transwell chamber and tube assay respectively. The express of Arg I, eNOS, iNOS mRNA of RF/6A cells were measured by real-time polymerase chain reaction (RT-PCR), Enzyme-linked immuno sorbent assay (ELISA) was used to detect the expression of NO and interleukine (IL)-1b of RF/6A cells. Results The proliferation, migration, and tube formation ability of group A (t=2.367, 5.633, 7.045;P＜0.05) and group C (t=5.260, 6.952, 8.875;P＜0.05) were significantly higher than group B. RT-PCR results showed the Arg I and iNOS expression in group B was higher than that in group A (t=6.836, 3.342;P＜0.05) and group C (t=4.904, 7.192;P＜0.05). The eNOS expression in group B was lower than that in group A and group C (t=4.165, 6.594;P＜0.05). ELISA results showed NO expression in group B was lower than that in group A and group C (t=4.925, 5.368;P＜0.05). IL-1b expression in group B was higher than that in group A and group C (t=5.032, 7.792;P＜0.05). Conclusions Nor-NOHA has a protective effect on cultured RF/6A cells in vitro and can enhance its proliferation, migration and tube formation. The mechanism may be inhibiting the oxidative stress by balancing the expression of Arg/NOS.
Objective To establish a rapid in vitro culture method of human choroidal endothelial cells (HCEC) and the cellular Characteristics to provide an in vitro model for researches of choroiretinal diseases which involved the HCEC. Methods The human choroidal tissues were digested in two steps by trypsin and collagenase, and the HCEC were obtained and cultured after the digested cell suspension was sorted and purified with magnetic beads of CD31 Dynabeads. The characteristics of HCMEC were observed by the morphologic observation method, transmission electron microscopy, and immunohistochemical staining with FⅧ factor, CD31, and CD34. Results The cultured HCEC were polygonal and oval, and after amalgamation, the cells had slabstone-like appearance. After the subculture, the configuration of HCEC remained the same, and represented cobblestone appearance with less magnetic beads attached on the cellular surface after HCEC converged into a single layer. The Weibel-Palade body which is the characteristic marker of endothelial cells was found. The staining of FⅧ fatcor, CD31, CD34 were positive. Conclusion HCEC can be cultured in vitro successfully with our method, which is easy to get sufficient number of highly purified HCEC. (Chin J Ocul Fundus Dis, 2007, 23: 126-129)