ObjectiveTo observe the expression of vascular endothelial growth factor (VEGF) and aquaporin 4 (AQP4) in the inner limiting membrane (ILM) of diabetic retinopathy (DR) with macular edema, and analyze the correlation between VEGF and AQP4 expression. Methods A cross-sectional study. From September 2019 to September 2020, 38 eyes of 38 patients with DR and idiopathic macular hole (iMH) who underwent vitrectomy (PPV) combined with ILM stripping at the Hangzhou campus of The Affiliated Eye Hospital of Wenzhou Medical University at Hangzhou were included in the study. Among them, there were 25 males and 13 females who aged 37-76 years old, average age was 59±10 years old; All eye included 15 right eyes and 23 left eyes. iMH and DR included 9 eyes in 9 cases and 29 eyes in 29 cases, respectively, and they were divided into iMH group and DR group. The DR group was divided into DME group and no DME group according to whether it was accompanied by diabetic macular edema (DME), with 14 eyes and 15 eyes respectively. After the stripped ILM tissue was fixed, immunofluorescence analysis was performed to obtain a picture of the fluorescence mode of AQP4 and VEGF, and the fluorescence intensity value of VEGF and AQP4 was measured by Image J software. The differences of VEGF and AQP4 immunofluorescence values in the specimens between groups were compared by one-way analysis of variance. The correlation between the fluorescence intensity of AQP4 and the fluorescence intensity of VEGF was analyzed by Pearson correlation analysis. Results The average fluorescence intensity values?of VEGF and AQP4 in ILM specimens of DME group, no DME group and iMH group were 38.96±7.53, 28.25±3.12, 30.07±4.84 and 49.07±8.73, 37.96±6.45, 38.08±5.04, respectively. The average fluorescence intensity of VEGF and AQP4 in the ILM specimens of the DME group was significantly higher than that of the no DME group and iMH group, and the difference was statistically significant (F=13.977, 9.454; P＜0.05). The average fluorescence intensity values of VEGF and AQP4 on IML specimens in the DR group were 33.80±7.91, 43.76±9.44, respectively. The results of Pearson correlation analysis showed that the fluorescence intensity of VEGF and AQP4 in the ILM specimens of the DR group was significantly positively correlated (r=0.597, P=0.003). ConclusionsThe expressions of VEGF and AQP4 in ILM of eyes with DR and DME are significantly increased compared with those without DME. The expression of VEGF and AQP4 in ILM of eyes with DR is positively correlated.
ObjectiveTo observe the effect of conditional knocking out (KO) vascular endothelial growth factor (VEGF) gene on the mouse model of oxygen induced retinopathy (OIR).MethodsThe conditional VEGF KO mice were generated using Cre-Loxp technology, resulting in the deletion of VEGF in a portion of Müller cells permanently in mouse retina. Cre positive was CKO mice, Cre negative was NKO mice. OIR was induced by keeping mice in 75% oxygen at postnatal 7 days (P7) to P12 and in room air from P12 to P17 (each 20 mice for CKO and NKO, respectively). The mice mortality was analyzed. At day P17, the percentage of retinal avascular area was calculated using retinal flat-mounting with fluorescence angiography, the number of vascular endothelial cell nucleus breaking through retinal inner limiting membrane was counted with hematoxylin eosin (HE) staining of retinal sections, and the expression of hypoxia-inducible factor-1α (HIF-1α) was detected by immunofluorescence analysis. ResultsDuring the development of OIR, the mortality rate of CKO mice (65.00%) was higher than that of NKO mice (30.00%) with the significant difference (x2=4.912, P=0.027). At day P17, all the mice retinas were harvested. The retinal fluorescence angiography displayed that the normal retinal vascularization of CKO mice was delayed, and large avascular areas were observed. Meanwhile, rare new vascular plexus was found in CKO mice and the thickness of whole retina decreased dramatically. In contrast, NKO mice developed larger area of normal retinal vascular network structure with higher blood vessel density and more new vascular plexus with obvious fluorescein leakage. The percentage of avascular area in CKO mice [(28.31±11.15)%] was higher than NKO mice [(16.82±7.23)%] with the significant difference (t=2.734, P=0.014). The HE staining of retinal sections indicated smaller counts of vascular endothelial cell nucleus breaking through retinal inner limiting membrane in CKO mice (26.10±6.37) when compared to NKO mice (28.80±7.59) , the difference was significant (t=2.437, P=0.016). The immunofluorescence analysis showed stronger expression of HIF-1α in CKO mice than NKO mice, which was mainly located in the retinal ganglion cell layer.ConclusionsThe local VEGF gene knockout partially inhibits retinal neovascularization in OIR mice. However, it also suppresses the normal retinal blood vascular development with a decrease of OIR mice survival ability.
Proliferative vitreoretinopathy (PVR) is a common complication and major cause of blindness of ocular trauma. Many cytokines, including vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), participate in the process of the pathogenesis of traumatic PVR. VEGF competitively inhibits binding of PDGF to its receptor (PDGFRα), enables indirect activation of PDGFRα by non-PDGF ligands, resulting in reduced p53 expression, cell proliferation and migration, which is a key point in the pathogenesis of traumatic PVR.
ObjectiveTo compare the function and action pathways of VEGFA, VEGFB and VEGFC in VEGF family of mouse eye.MethodsUsing the BXD mouse gene data in Genenetwork database as template to compare and study the similarities and differences of VEGFA, VEGFB and VEGFC molecular pathways or potential functions in the whole genome expression spectrum of BXD recombinant mouse inbred line population, with multiple analytical methods and statistical strategies were used, such as gene expression level, target genes comparison, top genes comparison associated to target genes, expression Quantitative Trait Loci (eQTL).ResultsMatrix comparison showed strong positive correlation between two probes of VEGFC (r=0.732, P＜0.01), weak correlation between VEGFA 1420909 and VEGFC 1440739, VEGFA 1451959 and VEGFC 1451803, VEGFC 1419417959 and VEGFC 1439766, VEGFC 1451803 and VEGFC 1439766 (P＜0.05); there was no correlation between VEGFA 1420909 and four other genes except VEGFC 1440739, VEGFA 1451959 and VEGFC 1440739, VEGFB 1451803 and VEGFA 1420909/VEGFC 1419417/VEGFC 1440739 (P ＞0.05). In the comparative analysis of the relevant Top50 genes of each VEGF gene, most of the genes in BXD mouse were not significantly correlated with VEGFA, VEGFB and VEGFC except for the weak association of individual related genes. The results of eQTL analysis showed that each probe of VEGF gene was located on different chromosomes.ConclusionsThe expression levels and positive and negative correlations of VEGFA, VEGFB and VEGFC were different in the VEGF family of mouse eye, suggesting that these genes may play their role through different pathways.
Objective To observe the effect of tetramethypyrazine (TMP) on the expression of hypoxia-related factors in human umbilical vein endothelial cells (HUVECs). Methods The second to fifth passage cultured HUVECs were divided into five groups: control group, CoCl2induced hypoxic group and 50, 100, 200 mu;mol/L TMP treatment groups. HUVECs in control group were not treated. HUVECs inCoCl2induced hypoxic group were treated with 150 mu;mol/LCoCl2for four hours. HUVECs in 50, 100, 200 mu;mol/L TMP treated groups were pretreated with 150 mu;mol/LCoCl2 for four hours, followed by treatment with 50, 100, 200 mu;mol/L TMP for eight hours. Real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA levels of prolyl hydroxylase 2 (PHD2), hypoxia-induced factor-1alpha;(HIF-1alpha;) and vascular endothelial growth factor (VEGF). Protein levels of PHD2, HIF-1alpha;, and VEGF were detected using Western blot. Results Compared with the control group, theCoCl2 induced hypoxic group showed decreased mRNA and protein levels of PHD2 (t=3.734, 3.122;P＜0.05), while those of HIF-1alpha; and VEGF increased (HIF-1alpha; mRNA:t=4.589,P＜0.05; HIF-1alpha; protein:t=3.778,P＜0.05. VEGF mRNA:t=3.926,P＜0.05; VEGF protein:t=3.257,P＜0.05). Compared with theCoCl2 induced hypoxic group, 50, 100, 200 mu;mol/L TMP treated groups showed increased mRNA and protein levels of PHD2 (PHD2 mRNA: t=3.286, 3.617, 3.886;P＜0.05. PHD2 protein: t=2.813, 3.026, 3.078; P＜0.05); while those of VEGF decreased (VEGF mRNA: 50 mu;mol/L TMP: t=1.696,P＞0.05; 100 mu;mol/L TMP:t=2.974,P＜0.05; 200 mu;mol/L TMP: t=3.492,P＜0.05; VEGF protein: 50 mu;mol/L TMP: t=1.986,P＞0.05; 100 mu;mol/L TMP: t=2.976,P＜0.05; 200 mu;mol/L TMP:t=3.136,P＜0.05); although changes in HIF-1alpha;mRNA levels were not statistically significant (t=1.025, 0.726, -1.386;P＞0.05), showed a decrease in HIF-1alpha;protein levels (50 mu;mol/L TMP: t=2.056,P＞0.05; 100 mu;mol/L TMP:t=3.058,P＜0.05; 200 mu;mol/L TMP:t=3.828,P＜0.05). ConclusionIn HUVECs, TMP can upregulate the mRNA and protein expression of PHD2, while down regulating HIF-1alpha; protein expression and VEGF mRNA and protein expression under acute hypoxic conditions.
ObjectiveTo investigate the role of sonic hedgehog (Shh) signal transduction pathway in the expression of vascular endothelial growth factor (VEGF) under hypoxia in cultured human retinal pigment epithelial (hRPE) cells.
MethodsARPE-19 were cultured and divided into normal ARPE-19 (Cont) and hypoxia group (100 μmol/L CoCl2 Cobalt Chloride +ARPE-19); hypoxia group was further divided into CoCl2 group, cyclopamine group (CYA) and dimethyl sulfoxide (DMSO) group. 20μmol/L cyclopamine was added to the CYA group 1 hour before hypoxia, 1‰DMSO was added into DMSO group at the same time. The hRPE cells were cultured under hypoxia for 4, 8, 12, 24 hours. The expression of Shh and VEGF were determined by Real-time fluorescent quantitate PCR (RT-PCR). The amount of VEGF in the hRPE-conditioned supernatant was measured using enzyme linked immunosorbent assay (ELISA) at 4, 8, 12, 24 hours, respectively.
ResultsRT-PCR tests showed that the level of Shh and VEGF of hRPE was time dependently increased (Shh: F=45.260, P=0.001; VEGF: F=264.938, P=0.001). The level of Shh and VEGF of hRPE in the group treated with cyclopamine was decreased (P < 0.01). ELISA tests showed that the amount of VEGF in hRPE supernatant was significantly increased in time-dependent manner (F=3 156.676, P=0.001), and it was down-regulated by cyclopamine under hypoxia (P < 0.01).
ConclusionShh signal transduction pathway could play a role in the VEGF expression induced by hypoxia in hRPE cells.
Objective To investigate the influence of vascular endothelial growth factor (VEGF) antagonist bevacizumab on the growth of human choroidal melanoma (CM) OCM-1 cell xenografts in nude mice, and to explore the probable mechanism.Methods OCM-1 cells were subcutaneously implanted on 18 nude mice to establish ectopic model of human CM. The nude mice with the tumor of 5 mm in diameter were randomly divided into three groups: untreated group (group A), normal saline （NS） group (group B), drug treated group (group C). Bevacizumab was intraperitoneally injected for 14 consecutive days in group C, and the same volume of NS was used at a same way in group B. The volume and weight of implanted tumor as well as inhibitory rates of drug on tumor were calculated, ki67 and survivin proteins were measured with immunohistochemistry, and the mRNA expression of VEGF and survivin were assessed by RT-PCR.Results The volume and weight of tumor was (598.86plusmn;321.81) mm3, (0.66plusmn;0.15) g; (1 715.15plusmn;278.16) mm3, (1.54plusmn;0.39) g and (1 750.23plusmn;206.36) mm3, (1.54plusmn;0.31) g in groups C, A and B, respectively. There were significant differences between group C and A (F=34.53, P=0.00) and group C and group B (F=8.69, P=0.01). The inhibitory rate of these three groups were 57.14%, 5.31%, 6.25%, respectively, and the proliferation index (PI) of ki67 in these three groups were (51.85plusmn;1.32)%, (46.30plusmn;1.39)%, (27.90plusmn;0.90)%, respectively, there were significant differences in ki67 PI between C group and A or B group (H=15.17, P=0.00). The expression of survivin mRNA was (0.49plusmn;0.02), (0.82plusmn;0.05) and (0.61plusmn;0.05) in groupss C, A and B, respectively, there were significant differences between C group and A or B group (F=15.17, P＜0.05) . The expression of VEGF mRNA was (0.32plusmn;0.08), (0.73plusmn;0.07), (0.80plusmn;0.04) in groups C, A and B, significant difference was found between group C and A or B group (F=12.05，P＜0.05). Conclusion Bevacizumab can inhibit the growth of human CM in nude mice probably by inhibiting the activity of VEGF and downregulating survivin expression of the tumor as well as inhibiting the growth of the tumor.
Objective To observe the microvessel density（MVD）and expression of vascular endothelial growth factor (VEGF) in retinoblastoma（RB）before and after comprehensive treatment and explore its clinical correlations with tumor infiltration and recurrence. Methods Sixty-one paraffin specimens of RB were divided into enucleation without comprehensive treatment group (untreated group，52 cases), planned enucleation before comprehensive treatment group (planned enucleation group，six cases) and tumor recurrence after comprehensive treatment group（recurrence group，three cases）. There were optic nerve invasion in 19 cases，no optic nerve infiltration in 33 cases. The MVD and VEGF expressions of 61 paraffin specimens were detected by streptavidin biotin-peroxidase (SP) immunohistochemistry with monoclonal antibody of CD34 and VEGF. Real time PCR was performed for the VEGF expression of planned enucleation group and recurrence group.Results In the untreated group，the MVD and VEGF expression of optic nerve infiltration cases were significantly higher than those of cases without optic nerve infiltration（t=-2.4685, P=0.017; chi;2=8.416 6，P=0.032 8）.Tumor microvessel regression, decreased MVD, occlusion and hyaline changes of blood vessels were observed in the planned enucleation group in the course of systemic chemotherapy. Many neovascularized capillaries and increased MVD were observed in tumor tissues of the recurrence group. The VEGF expression of planned enucleation group was lower than that in the recurrence group.Conclusions There was no significant difference on VEGF expression in RB between with and without comprehensive treatment. The increasing MVD and VEGF expression of cases without comprehensive treatment were related to the optic nerve infiltration. And the increasing MVD may also play an important role in RB recurrence after comprehensive treatment.
Objective To observe the influence of prolyl hydroxylase 2 (PHD2) expression on endothelial barrier dysfunction induced by high glucose in human retinal vascular endothelial cells (HRECs). Methods The HRECs were treated by different culture medium with various glucose concentrations (5 mmol/L glucose, 5 mmol/L glucose +25 mmol/L mannitol, 30 mmol/L glucose) as normal control group, mannitol control group and high glucose group, respectively. After the cells cultured for 24 and 48 hours, the protein levels of PHD2, hypoxia-inducible factor-1alpha; (HIF-1alpha;) and occludin was detected by Western blot; the expression of vascular endothelial growth factor (VEGF) in the supernatant was determined by enzymelinked immuno sorbent assay (ELISA); the transcription levels of PHD2, HIF-1alpha;, VEGF and occludin were determined by the reversetranscription polymerase chain reaction (RT-PCR); the paracellular permeability between endotheliums was detected by 7times;104 molecular weight FITCdextran. Results Compared with normal control group, the protein level of PHD2 in mannitol control group and high glucose group firstly decreased and then increased, the protein level of HIF-1alpha; increased while that of occludin decreased; the secretion of VEGF increased in high glucose group but not in mannitol control group (PHD2：F=7.618, 8.627;P＜0.05. HIF-1alpha;：chi;2=7.692, 7.652;P＜0.05. occludin：F=23.23, 7.317;P＜0.05. VEGF：F=10.768, 4.562; P＜0.05). Compared with normal control group, the mRNA levels of PHD2, HIF-1alpha;, VEGF and occludin in mannitol control group and high glucose group increased (PHD2：F=5.69, 14.27;P＜0.05. HIF-1alpha;：F=6.07, 10.47;P＜0.05. VEGF：F=12.31, 9.14;P＜0.05. occludin：F=8.77, 8.00;P＜0.05). Compared with normal control group, the paracellular permeability of mannitol control group and high glucose group increased (chi;2=20.57,F=56.09;P＜0.05). Conclusions High glucose induced altered expression of PHD2 which might play an important role in endothelial barrier dysfunction. The mechanism might be associated with HIF-1alpha; and VEGF.
Objective
To observe the influence of rAAV-mediated antisense vascular endothelial growth factor (rAAV-aVEGF165) on the expression of retinal VEGF in diabetic rats.
Methods
40 Sprague-Dawley rats induced diabetic rat model by intraperitoneal injection with streptozotocin (STZ). 32 rats were involved in study besides death and blood sugar recovery in experimental process, 16 spragud-Dawleg (SD) rats were received intravitreal injection with rAAV-aVEGF165 (1010 pfu) as experimental group, another group of Sprague-Dawleg (SD) rats were injected with phosphate buffered saline (PBS) as control group. One and five month after model establishment, the expression of retinal VEGF was evaluate by immunhistochemistry and Western blot; the retinal vasular was examined by transmission electron microscopy.
Results
On 1 month,the expression of retinal VEGF was lowest in each group. On 5 month, the expression of retinal VEGF was decreased in experimental group which compared to control, the difference are statistically significant （t=23.87,Plt;0.01）. The transmission electron microscopy results showed that retina has no obvious chages in experimental group, however,contral group showed fragmental thickening and splitting of basement membrane, swelling and deformation of endothelia cells,fingerlike prcess into the capillary cavity,and uneven distibution of heterochromatin in pericytes.
Conclusion
rAAV-aVEGF165 can reduce the expression of retinal VEGF thereby preventing occurrence and development of diabetic retinopathy. rAAV is an effective vectors of eye antisense gene.
（Chin J Ocul Fundus Dis，2008，24：255-258）
