【摘要】 目的 通过比较两种原代人脐静脉内皮细胞的分离培养方法并对细胞特异性抗原进行鉴定,探索提高原代内皮细胞体外培养存活率及纯化率的方法。 方法 采用一次性无菌注射器向人脐静脉灌注消化液,消化液的浓度和消化时间分别025%(质量体积比)胰蛋白酶,10 min和01%(质量体积比)胶原酶Ⅱ,15 min。通过在倒置显微镜下观察细胞的形态特点和用免疫荧光染色的方法对细胞进行鉴定,比较两种消化方法的优劣。 结果 01%胶原酶Ⅱ,15 min的消化方法较025%胰蛋白酶,10 min对原代人脐静脉内皮细胞有更好的分离效果,活细胞数量多且细胞纯度较高。免疫荧光染色结果表明细胞内有Ⅷ因子相关抗原表达。结论 胶原酶Ⅱ可以有效分离脐静脉内皮细胞,最佳消化条件是01%胶原酶Ⅱ,37℃,15 min。【Abstract】 Objective To explore the optimal method for primary culture of human umbilical vein endothelial cells (HUVECs). Methods HUVECs were prepared from human umbilical cords by 01% collagenase Ⅱ digestion for 15 minutes and 025 trypsinase digestion for 10 minutes,respectively. HUVECs were observed under inverted microscope and identified by immunofluorescence.The two methods of digestion were compared. Results More HUVECs were harvested through the method of 01% collagenase Ⅱ for 15 minutes,which expressed Ⅷ related antigen. Conclusion The method of 0.1% collagenase Ⅱ digestion for 15 minutes is a better choice to isolate HUVECs.
Objective To investigate the effect of Nodal protein on retinal neovascularization under hypoxia. MethodsIn vivo animal experiment: 48 healthy C57BL/6J mice were randomly divided into normal group, oxygen-induced retinopathy (OIR) group, OIR+dimethyl sulfoxide (DMSO) group and OIR+SB431542 group, with 12 mice in each group. Retinal neovascularization was observed in mice at 17 days of age by retina flat mount. Counts exceeded the number of vascular endothelial nuclei in the retinal inner boundary membrane (ILM) by hematoxylin eosin staining. In vivo cell experiment: human retinal microvascular endothelial cells (hRMEC) were divided into normal group, hypoxia group, hypoxia+DMSO group and hypoxia +SB431542 group. The cell proliferation was detected by thiazolyl blue colorimetry (MTT). The effect of SB431542 on hRMEC lumen formation was detected by Matrigel three-dimensional in vitro molding method. Cell migration in hRMEC was detected by cell scratch assay. The Seahorse XFe96 Cell Energy Metabolism analyzer measured extracellular acidification rate (ECAR) of intracellular glycolysis, glycolysis reserve, and glycolysis capacity. One-way analysis of variance was used to compare groups. ResultsIn vivo animal experiment: compared with normal group, the neovascularization increased in OIR group (t=41.621, P＜0.001). Compared with OIR group, the number of vascular endothelial nuclei breaking through ILM in OIR+SB431542 group was significantly reduced, and the difference was statistically significant (F=36.183, P＜0.001). MTT test results showed that compared with normal group and hypoxia+SB431542 group, the cell proliferation of hypoxia group and hypoxia+DMSO group was significantly increased, and the difference was statistically significant (F=39.316, P＜0.01). The cell proliferation of hypoxia+SB431542 group was significantly lower than that of hypoxia+DMSO group, and the difference was statistically significant (t=26.182, P＜0.001). The number of intact lumen formation and migration cells in normal group, hypoxia group, hypoxia+DMSO group and hypoxia+SB431542 group were statistically significant (F=34.513, 41.862; P＜0.001, ＜0.01). Compared with the hypoxia+DMSO group, the number of intact lumen formation and migrating cells in the hypoxia+SB431542 group decreased significantly, and the differences were statistically significant (t=44.723, 31.178; P＜0.001, ＜0.01). The results of cell energy metabolism showed that compared with the hypoxia +DMSO group, the ECAR of intracellular glycolysis and glycolysis reserve in the hypoxia +SB431542 group was decreased, and the ECAR of glycolysis capacity was increased, with statistical significance (t=26.175, 33.623, 37.276; P＜0.05). ConclusionSB431542 can inhibit the proliferation, migration and the ability to form lumens, reduce the level of glycolysis of hRMECs cells induced by hypoxia.
Vascular endothelial cell(VEC) is a kind of simple squamous epithelium lined on the inner surface of blood vessels. VEC is an important barrier between the blood and tissue and it also plays a key role in regulating inflammation, thrombosis, endothelial cells mediated vasodilatation and endothelial regeneration. These processes should be controlled by a variety of complex mechanism which requires us to find out. With results of the researches in vascular endothelial cell function, the important roles that microRNA in vascular endothelial cell function draws more and more researchers' attention. MicroRNAs control gene expression in post-transcriptional level and affect the function of endothelial cells. This review focuses on the research progress on regulatory mechanism of microRNA to endothelial cell inflammation, thrombosis, vasodilation and endothelium regeneration.
OBJECTIVE: To determine an optimal co-culture ratio of the rabbit periosteal osteoblasts (RPOB) and rabbit renal vascular endothelial cells(RRVEC) without direct contact for future study of bone tissue engineering. METHODS: RPOB and RRVEC in the ratios of 1:0(control group), 2:1(group 1), 1:1(group 2) and 1:2(group 3) were co-cultured by six well plates and cell inserts. Four days later, the proliferation of RPOB and RRVEC were examined through cell count. Differentiated cell function was assessed by alkaline phosphatase (ALP) activity assay and 3H proline incorporation assay. RESULTS: When RPOB and RRVEC were indirectly co-cultured, the proliferation of RPOB and 3H proline incorporation was higher in group 1 than in the other experimental groups and control group (P lt; 0.05). ALP activity of RPOB was higher in group 1 than in control group and group 3 (P lt; 0.05), but there was no significant difference between group 1 and group 2 (P gt; 0.05). CONCLUSION: These results suggest that RPOB and RRVEC co-cultured in a ratio of 2:1 is optimal for future study of bone tissue engineering.
Objective To investigate the relationship of cluster of differentiation 40L (CD40L) between inflammatory response mediated by vascular endothelial injury and Stanford A type aortic dissection (STAAD). Methods In this study from August 2016 to February 2017, a total of 215 blood samples from 95 STAAD patients (67 males and 28 females aged 48.33±12.19 years) and 120 healthy volunteers (94 males and 26 females aged 48.64±10.13 years) were collected. The patients with aortic dissection were taken blood 1 hour before the operation and the healthy volunteers were taken blood from the elbow vein. All STAAD patients were diagnozed by computed tomography angiography (CTA) and patients with Marfan syndrome were excluded. Blood samples were tested by enzyme-linked immunosorbent assay (ELISA) for CD40L, vascular cell adhesion molecule (VCAM-1), E-selectin, interleukin-1 (IL-1) beta, IL-6, tumor necrosis factor-alpha (TNF-α) and so on. ResultsCompared with the healthy population, the level of SCD40L(26.87±5.50 ng/ml vs. 13.39±4.03 ng/ml, P<0.001) in the STAAD patients was significantly higher. E-Selectin (116.62±25.24 ng/ml vs. 77.05±14.30 ng/ml, P<0.001), VCAM-1 (P<0.001), TNF-α (55.35±9.12 ng/ml vs. 37.33±5.61 pg/ml, P<0.001), IL-1β (62.12±13.37 ng/ml vs. 48.68±9.86 pg/ml, P<0.001), IL-6 (499.54±90.45 ng/ml vs. 422.44±34.00 pg/ml, P<0.001) significantly increased. Conclusion The increased expression of SCD40L in STAAD patients and the inflammatory reaction induced by endothelial injury in aortic dissection patients are obvious.
Objective To examine the effects of hypoxia on endothelial-to-mesenchymal transition of porcine pulmonary arterial endothelial cells ( PAECs) .Methods The porcine PAECs were divided into a normoxia group and a hypoxia group. The cells in two groups were exposed to normoxic or hypoxic condition for 1,4, and 7 days respectively. The immunofluorescence,Western blot and RT-PCR were used to detect the protein and mRNA expressions of VE-cadherin and α-SMA. Results The porcine primary PAECs formed typical monolayer of cobblestone appearance on normoxia condition, and had a spindle-shaped appearance on hypoxia condition. Immunofluorescence results showed that these PAECs expressed mesenchymal cells specific marker of α-SMA. With the hypoxic time prolongation, the ratio of transdifferentiated smooth musclelike cells from PAECs was gradually increased ( P lt; 0. 01) . Western blot assay demonstrated that the expression level of VE-cadherin protein and mRNA was reduced gradually, but the expression level of α-SMA protein and mRNA was increased. Conclusion Hypoxia can induce endothelial-to-mesenchymal transition, which may be involved in the development of a variety of diseases.
ObjectiveTo review the research progress on the role and mechanism of matrix stiffness in regulating endothelial cell sprouting. MethodsThe related literature at home and abroad in recent years was extensively reviewed, and the behaviors of matrix stiffness related endothelial cell sprouting in different cell cultivation conditions were analyzed, and the specific molecular mechanism of matrix stiffness regulating related signal pathways in endothelial cell sprouting was elaborated. Results In two-dimensional cell cultivation condition, increase of matrix stiffness stimulates endothelial cell sprouting within a certain range. However, in three-dimensional cell cultivation condition, the detailed function of matrix stiffness in regulating endothelial cell sprouting and angiogenesis are still unclear. At present, the research of the related molecular mechanism mainly focuses on YAP/TAZ, and roles of its upstream and downstream signal molecules. Matrix stiffness can regulate endothelial cell sprouting by activating or inhibiting signal pathways to participate in vascularization. ConclusionMatrix stiffness plays a vital role in regulating endothelial cell sprouting, but its specific role and molecular mechanism in different environments remain ambiguous and need further study.
ObjectiveTo investigate the mechanism of G protein coupled receptor kinase interacting protein 1 (GIT1) affecting angiogenesis by comparing the differentiation of bone marrow mesenchymal stem cells (BMSCs) differentiated into endothelial cells between GIT1 wild type mice and GIT1 gene knockout mice.MethodsMale and female GIT1 heterozygous mice were paired breeding, and the genotypic identification of newborn mice were detected by PCR. The 2nd generation BMSCs isolated from GIT1 wild type mice or GIT1 gene knockout mice were divided into 4 groups, including wild type control group (group A), wild type experimental group (group A1), GIT1 knockout control group (group B), and GIT1 knockout experimental group (group B1). The cells of groups A1 and B1 were cultured with the endothelial induction medium and the cells of groups A and B with normal cluture medium. The expressions of vascular endothelial growth factor receptor 2 (VEGFR-2), VEGFR-3, and phospho-VEGFR-2 (pVEGFR-2), and pVEGFR-3 proteins were detected by Western blot. The endothelial cell markers [von Willebrand factor (vWF), platelet-endothelial cell adhesion molecule 1 (PECAM-1), and vascular endothelial cadherin (VE-Cadherin)] were detected by flow cytometry. The 2nd generation BMSCs of GIT1 wild type mice were divided into 4 groups according to the different culture media: group Ⅰ, primary cell culture medium; group Ⅱ, cell culture medium containing SAR131675 (VEGFR-3 blocker); group Ⅲ, endothelial induction medium; group Ⅳ, endothelial induction medium containing SAR131675. The endothelial cell markers (vWF, PECAM-1, and VE-Cadherin) in 4 groups were also detected by flow cytometry.ResultsWestern blot results showed that there was no obviously difference in protein expressions of VEGFR-2 and pVEGFR-2 between groups; and the expressions of VEGFR-3 and pVEGFR-3 proteins in group A1 were obviously higher than those in groups A, B, and B1. The flow cytometry results showed that the expressions of vWF, PECAM-1, and VE-Cadherin were significantly higher in group A1 than in groups A, B, and B1 (P<0.05), and in group B1 than in groups A and B (P<0.05); but no significant difference was found between groups A and B (P>0.05). In the VEGFR-3 blocked experiment, the flow cytometry results showed that the expressions of vWF, PECAM-1, and VE-Cadherin were significantly higher in group Ⅲ than in groupsⅠ, Ⅱ, and Ⅳ, and in group Ⅳ than in groups Ⅰ and Ⅱ (P<0.05); but no significant difference was found between groups Ⅰ and Ⅱ (P>0.05).ConclusionGIT1 mediates BMSCs of mice differentiation into endothelial cells via VEGFR-3, thereby affecting the angiogenesis.
Objective To investigate the effects of vascular endothelial growth factor C (VEGF-C) gene modified lymph nodes on promoting proliferation of lymphatic endothelial cells in the surrounding tissues. Methods Thirty-six Sprague Dawley rats, weighing 200.1-271.5 g, were randomly divided into 2 groups (n=18). After the in situ axillary lymph nodes transplantation models were established in both groups, 1.5 × 108 PFU Ad-VEGF-C-Flag and Ad-Flag were injected into the transplanted lymph nodes in experimental group and control group, respectively. At 3 days after injection, the axillary lymph nodes were harvested to observe the expression of Flag; at 1, 2, and 4 weeks after injection, the axillary lymph nodes and the surrounding tissues were harvested to observe the expression of Prxo-1 protein and to calculate the fluorescence density; at 2 and 4 weeks after injection, the absorbance (A) value of treated blood at 620 nm was calculated to observe lymphatic back-flow function improvement; the rats without treatment served as normal control group, and the rats with in situ axillary lymph nodes transplantation model served as blank control group. Results At 3 days after injection, the expression of Flag could be detected in experimental group and control group. The fluorescence density of Prox-1 protein in experimental group increased at 1, 2, and 4 weeks, and it was significantly higher than that in control group (P lt; 0.05). The A values of normal control group and blank control group were 0.539 ± 0.020 and 0.151 ± 0.007, respectively. The A values of experimental group and control group were 0.170 ± 0.011 and 0.168 ± 0.010 at 2 weeks, and 0.212 ± 0.016 and 0.197 ± 0.006 at 4 weeks, which were significantly lower than those of normal control group (P lt; 0.05), but no significant difference was found when compared with blank control group, and between the experimental group and control group (P gt; 0.05). Conclusion The VEGF-C gene modified lymph nodes can stimulate the proliferation of lymphatic endothelial cells in the surrounding tissues. However, it has no improved effect on lymphatic back-flow function in the affected limb.
Objective To explore the effects of adipose-derived stem cell released exosomes (ADSC-Exos) on the proliferation, migration, and tube-like differentiation of human umbilical vein endothelial cells (HUVECs). Methods Adipose tissue voluntarily donated by liposuction patients was obtained. The ADSCs were harvested by enzyme digestion and identified by flow cytometry and adipogenic induction. The ADSC-Exos were extracted from the supernatant of the 3rd generation ADSCs and the morphology was observed by transmission electron microscopy. The surface proteins (Alix and CD63) were detected by Western blot. The nanoparticle tracking analyzer NanoSight was used to analyze the size distribution of ADSC-Exos. After co-culture of PKH26 fluorescently labeled ADSC-Exos with HUVECs, confocal microscopy had been used to observe whether ADSC-Exos could absorbed by HUVECs. ADSC-Exos and HUVECs were co-cultured for 1, 2, 3, 4, and 5 days. The effect of ADSC-Exos on the proliferation of HUVECs was detected by cell counting kit 8 (CCK-8) assay. The expression of VEGF protein in the supernatant of HUVECs with or without ADSC-Exos had been detected by ELISA after 12 hours. Transwell migration assay was used to detect the effect of ADSC-Exos on the migration ability of HUVECs. The effect of ADSC-Exos on the tubular structure formation of HUVECs was observed by Matrigel experiments in vitro. The formation of subcutaneous tubular structure in vivo was observed in BALB/c male nude mice via the injection of HUVECs and Matrigel with or without ADSC-Exos. After 2 weeks, the neovascularization in Matrigel was measured and mean blood vessel density (MVD) was calculated. The above experiments were all controlled by the same amount of PBS. Results After identification, the cultured cells were consistent with the characteristics of ADSCs. ADSC-Exos were circular or elliptical membranous vesicle with uniform morphology under transmission electron microscopy, and expresses the signature proteins Alix and CD63 with particle size ranging from 30 to 200 nm. Confocal microscopy results showed that ADSC-Exos could be absorbed by HUVECs. The CCK-8 analysis showed that the cell proliferation of the experimental group was better than that of the control group at each time point (P<0.05). The result of Transwell showed that the trans-membrane migration cells in the experimental group were significantly more than that in the control group (t=9.534, P=0.000). In vitro, Matrigel tube-forming experiment showed that the number of tube-like structures in the experimental group was significantly higher than that of the control group (t=15.910, P=0.000). In vivo, the MVD of the experimental group was significantly higher than that of the control group (t=16.710, P=0.000). The ELISA assay showed that the expression of VEGF protein in the supernatant of the experimental group was significantly higher than that of the control group (t=21.470, P=0.000). Conclusion ADSC-Exos can promote proliferation, migration, and tube-like structure formation of HUVECs, suggesting that ADSC-Exos can promote angiogenesisin vitro and in vivo.