Objective To observe and preliminarily explore the effects of Deferasirox (DFX) on lipid peroxidation and ferroptosis in human retinal endothelial cells (HREC). MethodsA cell experimental study. Divided the in vitro cultured HREC into normal glucose (NG) group, high glucose (HG) group, NG+DFX group, HG+DFX group, NG+DFX+ferric ammonium citrate (FAC) group, and HG+DFX+FAC group. Light microscope was used to observe the morphology of the cells; cell proliferation was detected by Cell Counting Kit-8 assay, and Calcein-AM staining was used to detect the unstable iron pool (LIP) content; enzyme-linked immunosorbent assay reader was used to detect the reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and oxidized glutathione (GSSG); Western blot was used to detect the relative protein expression of Glutathione Peroxidase 4 (GPX4) and Solute Carrier Family 7 Member 11 (SLC7A11). Two-tailed Student t test was used for comparison between the two groups; one-way ANOVA was used for comparison between multiple groups. ResultsCompared with the HG group and the HG+DFX+FAC group, the cell proliferation rate and the contents of GSH and the relative protein expression of GPX4, and SLC7A11 in the HG+DFX group were significantly increased, and the differences were statistically significant (F=150.70, 21.02, 26.09, 52.62; P＜0.001). The contents of LIP, ROS, MDA, and GSSG were significantly decreased, and the differences were statistically significant (F=807.20, 16.94, 31.62, 19.21; P＜0.001). ConclusionsHigh glucose significantly induces an increase in LIP, lipid peroxidation, and ferroptosis in HREC. Deferasirox inhibits lipid peroxidation and ferroptosis in HREC by downregulating LIP levels.
Objective To observe the proliferation and migration of endothelial cells after 30% total burn surface area (TBSA) of deep partial thickness scald, and the effect of basic fibroblast growth factor (bFGF) on angiogenesis during wound healing.Methods A total of 133 male Wistar ratswere divided randomly into normal control (n=7), injured control group (n=42), bFGF group (n=42) andanti-c-fos group (n=42). The apoptosis expression of fibroblasts was determinedwith in situ hybridization and the changes of proliferation cell nuclear antigen(PCNA), focal adhesion rinase(FAK), c-fos and extracellular signalregulated kinase(ERK) proteins expression were detected with immunohistochemistry staining technique after 3 hours, 6 hours, 1 day, 3 days, 7 days, 14 days and 21 days of scald.Results In injured control group and bFGF group, theproliferation rate of the vascular endothelial had evident changes 7 days and14 days after scald； the expression of FAK was increased 14 days after scald. ERK proteins expression was different between injury control group and bFGF group at initial stage after scald. Stimulation of ERKs by bFGF led to up-regulation of c-fos and b expression of FAK. Conclusion Exogenous bFGF extended the influence on wound healing process by ERK signaling pathway, affecting migration cascade of vascular endothelial cell. The oncogene proteins play an important role on accelerating angiogenesis duringwound healing.
Immuno-fluorescence technique can qualitatively determine certain nuclear translocation, of which NF-κB/p65 implicates the activation of NF-κB signal pathways. Immuno-fluorescence analysis software with independent property rights is able to quantitatively analyze dynamic location of NF-κB/p65 by computing relative fluorescence units in nuclei and cytoplasm. We verified the quantitative analysis by Western Blot. When we applied the software to analysis of nuclear translocation in lipopolysaccharide (LPS) induced (0.5 h, 1 h, 2 h, 4 h) primary human umbilical vein endothelial cells (HUVECs), we found that nuclear translocation peak showed up at 2h as with calculated Western blot verification results, indicating that the inventive immuno-fluorescence analysis software can be applied to the quantitative analysis of immuno-fluorescence.
Objective To study the biological behavior of osteoblast and vascular endothelial cell culture. Methods The osteoblasts and vascular endothelial cells were obtained from calvarial bone and renal cortox of 2-week rabbits respectively. The experiment were divided into group A (osteoblasts), group B (vascular endothelial cells) and group C(co-cultured osteoblasts and vascular endothelial cells). The cells were identified with cytoimmunochemical staining. The cellular biological behavior and compatibilitywere observed under inverted phase contrast microscope and with histological staining. The cells viability and alkaline phosphatase(ALP) activity were measured. Results The cytoimmunochemical staining showed that the cultured cells were osteoblasts and vascular endothelial cells .The cellular compatibility of osteoblasts and vascular endothelial cells was good. The ALP activity was higher in group C than in group A and group B(P＜0.01), and it was higher in group A than in group B(P＜0.05). In group C, the cellproliferation were increased slowly early, but fast later. Conclusion Thecellular compatibility of osteoblasts and vascular endothelial cells were good. The vascular endothelial cells can significantly increased the osteoblast viability and ALP activity,and the combined cultured cells have greater proliferation ability.
Objective To study the differenation of adult marrow mesenchymal stem cells(MSCs) into vascular endothelial cells in vitro and to explore inducing conditions. Methods MSCs were isolated from adult marrow mononuclear cells by attaching growth. MSCs were divided into 4 groups to induce: the cells seeded at a density of 5×103/cm2 in 2% and 15% FCS LDMEM respectively (group1 and group 2)， at a density of 5×104/cm2 in 2% and 15% FCS LDMEM respectively (group 3 and group 4); vascular endothelial growth factor(VEGF) supplemented with Bovine pituitary extract was used to induce the cell differentiation. The differentiated cells were identified by measuring surfacemarks (CD34, VEGFR2, CD31 and vWF ) on the 14th day and 21st day and performed angiogenesis in vitroon the 21st day.The cell proliferation index（PI）of different inducing conditions were measured. Results After induced in VEGF supplemented with Bovine pituitary extract, the cells of group 3 expressed the surface marks CD34, VEGFR-2, CD31 and vWF on the 14th day, the positive rates were 8.5%, 12.0%, 40.0% and 30.0% respectively, and on the 21st day the positive ratesof CD34 and VEGFR2 increased to 15.5％ and 20.0％, while the other groups did not express these marks; the induced cells of group 3 showed low proliferating state(PI was 10.4%) and formed capillary-like structure in semisolid medium. Conclusion Adult MSCs can differentiate into vascular endothelial cellsafter induced by VEGF and Bovine pituitary extract at high cell densities and low proliferatingconditions，suggesting that adult MSCs will be ideal seed cells forthe therapeutic neovascularization and tissue engineering.
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 relationships between circulating tumor cells (CTCs), circulating tumor endothelial cells (CTECs) and treatment methods in patients with nasopharyngeal carcinoma (NPC) at different stages of treatment. Methods The data of NPC patients at different treatment periods in West China Hospital of Sichuan University from March 2016 to November 2019 were retrospectively collected. The patients received CTCs test and part of those patients received CTECs test, by subtraction enrichment-immunostaining-fluorescence in situ hybridization. The relationships of CTCs and CTECs with radiotherapy and chemotherapy, and the correlations between CTCs and CTECs in NPC patients were analyzed. Results A total of 191 patients were included. Among them, there were 66 cases before initial treatment, 38 cases after induction chemotherapy, and 87 cases after concurrent chemoradiotherapy. A total of 127 patients received CTECs test, including 41 cases before initial treatment, 29 cases after induction chemotherapy, and 57 cases after concurrent chemoradiotherapy. The positive rates of CTCs were 89.4%, 81.6% and 69.0% respectively in the three stages of treatment, and the difference was statistically significant only between the pre-treatment group and the post-concurrent chemoradiotherapy group (P=0.003). The number of CTCs in the post-concurrent chemoradiotherapy group was lower than that in the pre-treatment group and the post-induction chemotherapy group (P<0.001, P=0.002). The number of triploid CTCs in the post-concurrent chemoradiotherapy group was significantly different from that in the pre-treatment group and the post-induction chemotherapy group (P=0.009, P=0.013). The number of tetraploid CTCs in the post-concurrent chemoradiotherapy group was significantly different from that in the post-induction chemotherapy group (P=0.007). The number of polyploidy (pentaploid or > 5 copies of chromosome 8) CTCs in the post-concurrent chemoradiotherapy group was significantly different from that in the pre-treatment group (P<0.001). The positive rates of CTECs were 70.7%, 82.8% and 64.9% respectively in the three stages of treatment, and the difference was not statistically significant (P>0.05). The number of CTECs in the post-concurrent chemoradiotherapy group was only lower than that in the post-induction chemotherapy group (P=0.009). There was no significant difference in the number of triploid or tetraploid CTECs among the three groups (P=0.265, P=0.088). The number of polyploid CTECs was statistically different only between the post-concurrent chemoradiotherapy group and the post-induction chemotherapy group (P=0.007). Spearman correlation analysis showed that there was a significant positive correlation between CTCs and CTECs (rs=0.437, P<0.001). Conclusions Concurrent chemoradiotherapy plays a decisive role in reducing the number of CTCs in the blood of NPC patients, while induction chemotherapy does not appear to directly cause changes in the number of CTCs. In NPC patients, different types of CTCs have different responses to different treatments. There is a significant positive correlation between CTECs level and CTCs level in NPC.
Objective To study the effect of vascular endothelial cell growth factor (VEGF) on repair of bone defect with cortical bone allograft. Methods Forty five New Zealand white rabbits, weighted 2.5-3.0 kg, were made bone defect model of 1.5 cm in length in the bilateral radii and then were randomly divided into 3groups. The defect was repaired with only cortical bone allograft in the control group, with the cortical bone allograft and local injection of human recombinantVEGF in the experimental group, and with the cortical bone allograft and abdominal injection of VEGF PAb3 in the antagonist group. Roentgenography, immunohistochemical staining and tetracycline labelling were carried out to evaluate the reparative results 1, 3, 5, 8 and 16 weeks after operation. Results Immunohistochemical staining results showed that a great deal of blood vessels formed in the experimental group, and the number of blood vessels increased gradually with the time and reached the highest value at the 8th week. Tetracyclinelabelling showed the same result.The best results in callus formation, ossification rate and count of microvascular density were shown in the experimental group, while those in the control group were significantly better than those in the antagonist group (Plt;0.05),but there was no significant difference between the experimental group and the control group at the 8th week and the 16th week (Pgt;0.05). Conclusion VEGF can accelerates the bone formation and angiogenesis in the bone allografts, thus it can promote the repair of bone defects.
Bone tissue regeneration and blood vessel formation are inseparable. How to realize the vascularization of bone repair scaffolds is an urgent problem in bone tissue engineering. The growth and development, mineralization maturity, reconstruction and remodeling, and tissue regeneration of bone are all based on forming an excellent vascularization network. In recent years, more and more researchers have used hydrogels to carry different cells, cytokines, metal ions and small molecules for in vitro vascularization and application in bone regeneration. Based on this background, this article reviews the hydrogel-based vascularization strategies in bone tissue engineering.
Objective To investigate the protocols of combined culture of human placenta-derived mesenchymal stem cells (HPMSCs) and human umbilical vein endothelial cells (HUVECs) from the same and different individuals on collagen material, to provide the. Methods Under voluntary contributions, HPMSCs were isolated and purified from human full-term placenta using collagenase IV digestion and lymphocyte separation medium, and confirmed by morphology methods and flow cytometry, and then passage 2 cells were cultured under condition of osteogenic induction. HUVECs were isolated from fresh human umbilical vein by collagenase I digestion and subcultured to purification, and cells were confirmed by immunocytochemical staining of von Willebrand factor (vWF). There were 2 groups for experiment. Passage 3 osteoblastic induced HPMSCs were co-cultured with HUVECs (1 ∶ 1) from different individuals in group A and with HUVECs from the same individual in group B on collagen hydrogel. Confocal laser scanning microscope was used to observe the cellular behavior of the cell-collagen composites at 1, 3, 5, and 7 days after culturing. Results Flow cytometry showed that HPMSCs were bly positive for CD90 and CD29, but negative for CD31, CD45, and CD34. After induction, alizarin red, alkaline phosphatase, and collagenase I staining were positive. HUVECs displayed cobble-stone morphology and stained positively for endothelial cell marker vWF. The immunofluorescent staining of CD31 showed that HUVECs in the cell-collagen composite of group B had richer layers, adhered and extended faster and better in three-dimension space than that of group A. At 7 days, the class-like microvessel lengths and the network point numbers were (6.68 ± 0.35) mm/mm2 and (17.10 ± 1.10)/mm2 in group A, and were (8.11 ± 0.62) mm/mm2 and (21.30 ± 1.41)/mm2 in group B, showing significant differences between the 2 groups (t=0.894, P=0.000; t=0.732, P=0.000). Conclusion Composite implant HPMSCs and HUVECs from the same individual on collagen hydrogel is better than HPMSCs and HUVECs from different individuals in integrity and continuity of the network and angiogenesis.