Objective To investigate the effect of the vascular endothelial growth factor (VEGF) gene therapy, the surgical delay, and the combination of the two therapeutic approaches on the survival of the rat over-area abdominal axial skin flap. Methods In 48 male Wistar rats (weight, 400-450 g), a model of the abdominal axial skin flap supplied by the superficial epigastric blood vessel was created. The rats were randomly divided into 6 groups: Group A (the blank group), Group B (the gene-therapy-during-operation group), Group C (the gene-therapy-before-operation group), Group D (themerely-surgical-delay group), Group E (the gene-therapy-during-surgical-delay group), and Group F (the gene-therapy-aftersurgical-delay group). Seven days after operation, the survival rate of the skin flap was measured; the specimens were harvested from the skin flap for a histological investigation of themicrovessels and for an immunohistochemical staining to observe the expression of VEGF165. Results The average survival rate of the skinflap was significantly greater in each of the treated groups than in Group A (Plt;0.05); the rate was the greater in Group E (Plt;0.05), but with no statistically significant difference between the other treated groups (Pgt;0.05). The average number of the microvessels was significantly greater in Groups B, C, E andF than in Groups A and D (Plt;0.05), but with no statistically significant difference between Groups B, C, E and F and between Groups A and D (Pgt;0.05). The lumen diameter of the microvessels was significantly greater in Group D than in Groups E and F (Plt;0.05), and the diameter was significantly greater in Groups D, E andF than in the other groups (Plt;0.05). More deposition of VEGF DNA detected by the immunohistochemical staining was in Groups B, C, E and F than in Groups A and D. There was no newly-formed blood vessel in the rat cornea in the treated groups.Conclusion Both the administration of pcDNA4-VEGF165 and the surgical delay can improve the survival of the rat abdominal axial skin flap, but the mechanism of the effect is different in explanation. The combination of the two therapeutic approaches can achieve a better effect.
Objective To investigate the inhibitory effects of fms-like typrosine kinase receptor sFlt-1 on retinal neovascularization (RNV).Methods Recombinant lentivirus sFlt-1（2-3）and sFlt-1（2-4）expressing the sFlt-1 (2-3) and (2-4) immunoglobulinlike regions of sFlt-1 were constructed. 96 seven-day-old C57/6J mice were randomly divided into 4 groups with 24 mice in each group. Group 1: normal control; group 2: experimental control; group 3: sFlt-1（2-3）; group 4: sFlt-1（2-4）.The mice in group 2-4 were exposed to hyperoxia with （75plusmn;2）% O2 for 5 days and then returned to normoxia with 21% O2;the mice received an intravitreal injection with 1 mu;l virus of empty vector, sFlt-1（2-3）,or sFlt-1（2-4）,respectively. Five days later, all mice underwent perfusion fluorecein angiography and retinal wholemont was made to observe the changes of retinal vessels; retinal sections were stained by hematoxylin and eosin and RNV endothelium cell nucleus were counted; vascular endothelial growth factor(VEGF) and VEGF receptor-2 (KDR/Flk-1) protein were measured by Western blot.Results Seventeen days after birth, the retinal area of fluorescein leakage and RNV, RNV nucleus which breaking through inner limiting membrane in group 3 and 4 were smaller or less than that in group 2（P＜0.01）; while VEGF protein didnprime;t changed much （P＞0.05）the expression of KDR/Flk-1 decreased significantly (P＜0.01). Conclusion sFlt-1（2-3）and sFlt-1（2-4）can inhibit the formation of oxygen-induced RNV,the former virus has a better effect.
【Abstract】Objective To investigate the change of vascular endothelial growth factor (VEGF) expression in HepG2 cells under hypoxia. Methods HepG2 cells were cultured under hypoxia（hypoxia group） and normal condition (control group). VEGF expression of HepG2 cells was examined by immunohistochemical staining. The growth of HepG2 cells was examined by MTT colorimetry and cell count. VEGF level in the culture medium was measured by ELISA.Results After 48 h and 72 h of culture, the growth rate of HepG2 cells in hypoxia group was lower than that in control group (P＜0.05). The cell count in hypoxia group (2.51×104/μl and 2.69×104/μl, respectively) was much lower than that in control group(3.01×104/μl and 3.52×104/μl) after 48h and 72h of culture (P＜0.05). In hypoxia group, VEGF level in the culture medium after 24 h and 48 h was higher than that in control group (P＜0.05, P＜0.01). Conclusion Hypoxia may enhance the VEGF expression in HepG2 cells and this could be the reason of high expression of VEGF after transcatheterized hepatic arterial chemoembolization.
Objective To observe the degradation of the polyactic glycolate acid (PLGA) microparticles with releasing-slowly vascular endothelial growth factor(VEGF) synthesized by the method of emulsification-diffusion. Methods The method of emulsification-diffusion is to incorporate VEGF into microparticles composed of biodegradable PLGA. The controlled release of microparticles are acquired. The content of the VEGF released slowly from PLGA microparticles in vitro was detected with ELISA at different time. Results We synthesized 100 releasing-slowly VEGF PLGA microparticles with the size of 0.20-0.33 μm by 5 times. The contents were 62±11 ng/L, 89±14 ng/L, and 127±19 ng/L in the 1st, the 2nd and the 3rd months after degradation, respectively. Conclusion The PLGAmicroparticles with releasing-slowly VEGF can be synthesized by the method of emulsification-diffusion.
ObjectiveTo observe the serum vascular endothelial growth factor (VEGF), apelin and heme oxygenase-1 (HO-1) levels in patients with type 2 diabetes mellitus (T2DM) and to explore their their relationship with diabetic retinopathy (DR).MethodsA total of 208 patients with T2DM and 50 healthy subjects (control group) from the Central Hospital of Western Hainan during January 2014 and December 2017 were selected in this study. Vision, slit lamp microscope, indirect ophthalmoscope and FFA examinations were performed on all the subjects. According to the results of the examinations combined with the DR clinical staging criteria, the patients were divided into non-DR (NDR) group, non-proliferative DR (NPDR) group, and proliferative DR (PDR) group, with 72, 76 and 60 patients in each, respectively. The clinical data of each group were recorded, and the levels of fasting blood glucose (FPG), HbA1c, total cholesterol (TC), three acylglycerol (TG), high density lipoprotein (HDL-C), low density lipoprotein (LDL-C), VEGF, apelin and HO-1 were detected in each group. The receiver operating characteristic curve (ROC) were used to analyze the value of VEGF, apelin and HO-1 in predicting the occurrence of PDR. Correlation analysis of serum VEGF, Apelin and HO-1 with clinical parameters in PDR patients by Pearson correlation analysis.ResultsThe level of VEGF (56.82±10.16 vs 91.74±22.83, 140.15±36.40, 195.28±42.26 pg/ml) and apelin (2.95±0.53 vs 4.68±0.74, 7.25±1.13, 10.16±1.35 ng/ml) in PDR group were significantly higher than those in NPDR, NDR and control groups (F=17.306, 21.814; P＜0.05). The level of HO-1 (50.37±10.14 vs 43.58±8.16, 30.25±6.28, 22.60±4.72 mmol/L) in PDR group was significantly lower than those in NPDR, NDR and control groups (F=15.827, P＜0.05). The ROC curve analysis showed that the best cut-off values of serum VEGF, apelin and HO-1 were 162.50 pg/ml, 8.30 ng/ml, 27.13 mmol/L, and the three combined to predict PDR of AUC (95%CI) was 0.906 (0.849−0.962), and their sensitivity (90.3%) and specificity (83%) were better. The correlation analysis showed that the VEGF, apelin and HO-1 of PDR patients were correlated with the course of diabetes (r=0.382, 0.416, −0.36; P＜0.05), FPG (r=0.438, 0.460, −0.397; P＜0.05) and HbAlc (r=0.375, 0.478, −0.405; P＜0.05), and the serum VEGF were correlated with apelin and HO-1 (r=0.793, −0.594; P＜0.01).ConclusionElevated serum VEGF and apelin levels and reduced HO-1 levels are associated with the progression of DR, and the three combination helps predict the occurrence of PDR.
Objective To study the expression and significance of CCR chemokine receptor-7 (CCR7) protein and vascular endothelial growth factor-D (VEGF-D) protein in the progression of breast cancer, including normal breast tissue, slight and moderate atypical hyperplasia, severe atypical hyperplasia and intraductal carcinoma in situ, as well as invasive ductal carcinoma. Methods Immunohistochemistry was used to detect the expression of CCR7 and VEGF-D protein in the nomal breast tissue (n=20), slight and moderate ductal atypical hyperplasia tissue (n=20), severe atypical hyperplasia and intraductal carcinoma in situ tissue, as well as invasive ductal breast carcinoma tissue (n=73). In addition, the D2-40 staining was also used to determine lymphatic microvessel density (LMVD). Meanwhile, the relationship between the expression of the two kinds of protein and clinicopathological factors/LMVD was analyzed by statistical analysis in breast cancer, and the correlation between expression of CCR7 protein and expression of VEGF-D protein was analyzed too. Results ①The positive rates of CCR7 protein (χ 2 =23.905，P<0.050) and VEGF-D protein (χ 2 =22.349，P<0.050) were gradually increased in the normal breast tissue group 〔CCR7 protein: 0 (0/20), VEGF-D protein: 5.0% (1/20)〕, slight and moderate atypical hyperplasia group 〔CCR7 protein: 5.0% (1/20), VEGF-D protein: 20.0% (4/20)〕, severe atypical hyperplasia and intraductal carcinoma in situ group 〔CCR7 protein: 30.0% (6/20), VEGF-D protein: 40.0% (8/20)〕, and invasive ductal carcinoma group 〔CCR7 protein: 47.9% (35/73), VEGF-D protein: 57.5% (42/73)〕. ②The LMVD value gradually increased in normal breast tissue group (2.00±1.02), slight and moderate atypical hyperplasia group (6.70± 3.48), severe atypical hyperplasia and intraductal carcinoma in situ group (9.01±2.13), as well as invasive ductal carcinoma group (16.32±4.07), there was significant difference between any 2 groups (P<0.050). ③The expressions of CCR7 protein and VEGF-D protein were correlated with clinical staging, histological grading, lymph node metastasis, and expression of human epidermal growth factor receptor-2 (HER-2) protein in patients with breast cancer (P<0.050), the higher positive rates of CCR7 and VEGF-D protein occurred in patients with higher histological grading, later clinical staging of Ⅲ+Ⅳ (compared with staging of Ⅰ+Ⅱ), lymph node metastasis (compared with no lymph node metastasis), and positive expression of HER-2 protein (compared with negative expression of HER-2 protein). The result indicated that LMVD value was related with expression of VEGF-D protein (r=0.623, P<0.010) in patients with breast cancer, but there was no correlation with expression of CCR7 protein (r=-0.303, P>0.050). Furthermore, there was weak positive correlation between expression of CCR7 protein and expression of VEGF-D protein in breast cancer (r=0.112, P<0.050). Conclusion The results strongly suggest that the expression levels of the VEGF-D protein and CCR7 protein indicate the potential of translation some extent, and they play an important role in the progression of breast cancer.
Anti-vascular dndothelial growth factor (VEGF) drugs have open up a new treatment channel for ocular neovascular diseases. A lots of clinical data has proved that anti-VEGF drugs are effective and safe. But we should also notice that long-term and excessive usage of anti-VEGF drugs brings some new problems and complications, and even affect the normal ocular physiological process of the angiogenesis and retinal blood flow. So, it is necessary to pay attention to the problems and potential risks of excessive usage of anti-VEGF therapies for ocular neovascular disease.
Objective To investigate the neuroprotective effects of recombinant adeno-associated virus (rAAV) expressing vascular endothel ial growth factor (VEGF) on traumatic spinal cord injury (SCI) of rat and its mechanisms. Methods The 144 male Sprague Dawley rats were randomly divided into 4 groups, and each group contained 36 rats. The rats in sham group (group A) received dorsal laminectomy without SCI and microinjection, the rats in model control group (group B), rAAV-green fluorescent protein (GFP) group (group C), and rAAV-hVEGF165-GFP group (group D) received dorsallaminectomy with SCI and injection of 20 μL sal ine, rAAV-GFP viruses, or rAAV-hVEGF165-GFP viruses, respectively. At 3 and 7 days after operation, Basso-Beattie-Bresnahan (BBB) score was used to evaluate the neurologic function. At 7 days after operation, Nissl’s body staining was used to evaluate the histopathological changes; apoptosis was confirmed by transmission electron microscope examination and TUNEL staining; the expression of aquaporin 4 (AQP-4) was detected by Western blot assay. At 1, 3, 5, and 7 days, ELISA assay was used to detect the VEGF165 protein expression. Results According to BBB scores, the neurologic function in group D was significantly better than those in groups B and C at 3 and 7 days after operation (P lt; 0.05). Nissl’s body staining showed that tissue damage in group D was significantly milder than those in groups B and C at 7 days after operation (P lt; 0.05). ELISA results showed that VEGF165 protein expression was slowly-released in low dose in group D, and the expression in group D was significantly higher than that in groups A, B, and C at 3, 5, and 7 days after operation (P lt; 0.05). The results of transmission electron microscope and TUNEL staining showed that apoptosis rate of spinal cord neurons in group D was significantly lower than that in groups B and C at 7 days after operation (P lt; 0.05). The results of Western blot showed that AQP-4 expression in group D was significantly decreased when compared with that in groups B and C at 7 days after operation (P lt; 0.05). Conclusion TherAAV expressing VEGF has neuroprotective effects by inhibiting apoptosis of spinal cord neurons and relieving spinal cord edema.
Objective To observe the effect of RNA interference (RNAi) on HepG2 hepatic cancer cell by small interfering RNA (siRNA). Methods siRNA targeting vascular endothelial growth factor (VEGF) gene was transfected into HepG2 cells by LipofectimineTM 2000. The VEGF mRNA and protein were respectively detected by real-time quantitive PCR and Western blot, and the concentration of VEGF protein in the cell culture supertant was determined by ELISA at 48 h after culture. Results The average efficiency of siRNA transfection was (90.4±2.9)% after 6 h cell culture. The expressions of VEGF mRNA and protein in HepG2 cells could be effectively suppressed by siRNA, and the concentration of VEGF protein in the cell culture supertant was also decreased. Conclusion siRNA can knock down the expression of VEGF gene and decrease the concentration of VEGF protein in HepG2 cells.
【Abstract】Objective To understand the features of lymphatic vessel, and to summarize the foundation and mechanism of the promotion and inhibition of tumor lymphangiogenesis recorded on the current studies of animal experiments and clinical researches. Methods The related literatures of the structural features of lymphatic vessel, lymphatic endothelial molecular markers, the origin of lymphatic tumors, the molecular mechanisms and regulatory factors were reviewed, and the relationship between tumor lymphangiogenesis and lymphatic metastasis, the treatment targeting at the formation of the anti-tumor lymphatic vessel and its existing problems were also analyzed. Results Hyperplasia of lymphatic vessels occurred during the process of tumor formation and progression. The structural features of the lymphatic vessels in the tumor were conducive to tumor lymphatic metastasis. In recent years, methods of anti-lymphangiogenesis and inhibition of tumor lymphatic metastasis had achieved considerable success in animal experiments. However, there were still a lot of problems need to be solved. Conclusion Tumor lymphangiogenesis has a significantly positive correlation between tumor lymphatic metastasis and patients’ prognosis, which may indicate that treatment against the formation of tumor lymphatic vessel maybe effective.