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.
ObjectiveTo evaluate the effects of icariin on autophagy induced by low-concentration of glucocorticoid and exosome production in bone microvascular endothelial cells (BMECs).MethodsBMECs were isolated from femoral heads resected in total hip arthroplasty and then intervened with hydrocortisone of low concentration (0, 0.03, 0.06, 0.10 mg/mL), which were set as groups A, B, C, and D, respectively. On the basis of hydrocortisone intervention, 5×10?5 mol/L of icariin was added to each group (set as groups A1, B1, C1 and D1, respectively). Western blot was used to detect the expressions of microtubule-associated protein 1 light chain 3B (LC3B) and dead bone slice 1 (p62) after 24 hours. Exosomes were extracted from BMECs treated with icariin (intervention group) and without icariin (non-intervention group), and the diameter and concentration of exosomes were evaluated by nanoparticle tracking analysis technique. The total protein content of exosomes was detected by BCA method, and the expressions of proteins carried by exosomes including CD9, CD81, transforming growth factor β1 (TGF-β1), and vascular endothelial growth factor A (VEGFA) were assessed by Western blot. The BMECs were further divided into three groups: BMECs in the experimental group and the control group were co-cultured with exosomes secreted by BMECs treated with or without icariin, respectively; the blank control group was BMECs without exosome intervention. The three groups were treated with hydrocortisone and Western blot was used to detect the expressions of LC3B and p62. The scratching assay was used to detect cell migration ability; angiogenic ability of BMECs was also assessed.ResultsWith the increase of hydrocortisone concentration, the protein expression of LC3B-Ⅱ increased gradually, and the protein expression of p62 decreased gradually (P<0.01). Compared with group with same concentration of hydrocortisone, the protein expression of LC3B-Ⅱ decreased and the protein expression of p62 increased after the administration of icariin (P<0.01). The concentration of exosomes in the intervention group was significantly higher than that in the non-intervention group (t=?10.191, P=0.001); and there was no significant difference in exosome diameter and total protein content between the two groups (P>0.05). CD9 and CD81 proteins were highly expressed in the non-intervention group and the intervention group, and the relative expression ratios of VEGFA/CD9 and TGF-β1/CD9 proteins in the intervention group were significantly higher than those in the non-intervention group (P<0.01). After co-culture of exosomes, the protein expression of p62 increased in blank control group, control group, and experimental group, while the protein expression of LC3B-Ⅱ decreased. There were significant differences among groups (P<0.05). When treated with hydrocortisone for 12 and 24 hours, the scratch closure rate of the control group and experimental group was significantly higher than that of the blank control group (P<0.05), and the scratch closure rate of the experimental group was significantly higher than that of the control group (P<0.05). When treated with hydrocortisone for 4 and 8 hours, the number of lumens, number of sprouting vessels, and length of tubule branches in the experimental group and the control group were significantly greater than those in the blank control group (P<0.05); the length of tubule branches and the number of lumens in the experimental group were significantly greater than those in the control group (P<0.05).ConclusionIcariin and BMECs-derived exosomes can improve the autophagy of BMECs induced by low concentration of glucocorticoid.
ObjectiveTo prepare polyurethane (PU) microspheres and evaluate its physicochemical properties and biocompatibility for biomedical applications in vitro.
MethodsThe PU microspheres were prepared by self-emulsification procedure at the emulsification rates of 1 000, 2 000, 3 000, and 4 000 r/min. The molecular structure was tested by Fourier transform infrared spectrometer and the surface and interior morphology of PU microspheres were observed by scanning electron microscopy (SEM). PU microspheres prepared at best emulsification rate were selected for the subsequent experiment. The human umbilical vein endothelial cells (HUVECs) were cultured and seeded on the materials, then cell morphology and adhesion status were observed by calcein-acetoxymethylester/pyridine iodide (Calcein-AM/PI) staining. The cells were cultured in the H-DMEM containing 10%FBS with additional 1% phenol (group A), in the extracts of PU prepared according to GB/T 16886.12 standard (group B), and in H-DMEM containing 10%FBS (group C), respectively. Cell counting kit 8 (CCK-8) assay was used to detect the cell viability. The blood compatibility experiments were used to evaluate the blood compatibility, the PU extracts as experimental group, stroke-physiological saline solution as negative control group, and distilled water as positive control group. The hemolytic rate was calculated.
ResultsThe SEM results of PU microspheres at the emulsification rate of 2 000 r/min showed better morphology and size. The microstructure of the PU was rough on the surface and porous inside. The Calcein-AM/PI staining showed that the HUVECs attached to the PU tightly and nearly all cells were stained by green. CCK-8 assays demonstrated that group B and group C presented a significantly higher cell proliferative activity than group A (P<0.05), indicating low cytotoxicity of the PU. The absorbance value was 0.864±0.002 in positive control group and was 0.015±0.001 in negative control group. The hemolysis rate of the PU extracts was 0.39%±0.07% (<5%), indicating no hemolysis.
ConclusionThe PU microspheres are successfully prepared by self-emulsification. The scaffold can obviously promote cell attachments and proliferation and shows low cytotoxicity and favorable blood compatibility, so it might be an ideal filler for soft tissue.
ObjectiveTo observe the effects of p21 activated kinase 4 (PAK4) on the mitochondrial function and biological behavior in retinal vascular endothelial cells. MethodsThe experimental study was divided into two parts: in vivo animal experiment and in vitro cell experiment. In vivo animal experiments: 12 healthy C57BL/6J male mice were randomly divided into normal control group and diabetes group, with 6 mice in each group. Diabetes mice were induced by streptozotocin to establish diabetes model. Eight weeks after modeling, quantitative real-time polymerase chain reaction and Western blots were performed to detect the expression of PAK4 in diabetic retinas. In vitro cell experiments: the human retinal microvascular endothelial cells (hRMEC) were divided into three groups: conventional cultured cells group (N group), empty vector transfected (Vector group); pcDNA-PAK4 eukaryotic expression plasmid transfected group (PAK4 group). WB and qPCR were used to detect transfection efficiency, while scratching assay, cell scratch test was used to detect cell migration in hRMEC of each group. In vitro white blood cell adhesion experiment combined with 4 ', 6-diamino-2-phenylindole staining was used to detect the number of white blood cells adhering to hRMEC in each group. The Seahorse XFe96 cell energy metabolism analyzer measures intracellular mitochondrial basal respiration, adenosine triphosphate (ATP) production, maximum respiration, and reserve respiration capacity. The t-test was used for comparison between the two groups. Single factor analysis of variance was used for comparison among the three groups. ResultsIn vivo animal experiments: compared with normal control group, the relative expression levels of PAK4 mRNA and protein in retina of diabetic mice were significantly increased, with statistical significance (t=25.372, 22.419, 25.372; P＜0.05). In vitro cell experiment: compared with the N group and Vector group, the PAK4 protein, mRNA relative expression and cell mobility in the hRMEC of PAK4 group were significantly increased, with statistical significance (F=36.821, 38.692, 29.421; P＜0.05). Flow cytometry showed that the adhesion number of leukocytes on hRMEC in PAK4 group was significantly increased, and the difference was statistically significant (F=39.649, P＜0.01). Mitochondrial pressure measurement results showed that the capacity of mitochondrial basic respiration, ATP production, maximum respiration and reserve respiration in hRMEC in PAK4 group was significantly decreased, with statistical significance (F=27.472, 22.315, 31.147, 27.472; P＜0.05). ConclusionOver-expression of PAK4 impairs mitochondrial function and significantly promotes leukocyte adhesion and migration in retinal vascular endothelial cells.
Objective To explore the effect of natural hirudin on proliferation of human microvascular endothelial cells (HMVECs) and its preliminary mechanism of promoting angiogenesis. Methods Three-dimensional culture models of HMVECs were established in vitro and observed by inverted phase contrast microscopy after 24 hours of culturing. Then, the three-dimensional culture models of HMVECs were treated with different concentrations (1, 4, and 7 ATU/mL) of the natural hirudin, respectively, and Dulbecco’s modified Eagle’s medium containing 10% fetal bovine serum as control. The cell proliferations of 4 groups were detected by cell counting kit 8 (CCK-8) method at 24, 48, and 72 hours; the angiogenesis of 4 groups were observed by tube formation assay at 24 hours; the expressions of vascular endothelial growth factor (VEGF) and Notch1 of HMVECs in 4 groups were observed by immunofluorescence staining at 24 hours. Results The observation of cells in three-dimensional culture models showed that HMVECs attached to Matrigel well, and the cells formed tube structure completely after 24 hours. The results of CCK-8 test showed that the absorbance (A) value of 1 and 4 ATU/mL groups were higher than that of control group at each time point (P<0.05), andA value of 4 ATU/mL group was the highest. The A value of 7 ATU/mL group was significantly lower than those of 1 and 4 ATU/mL groups and control group (P<0.05). The tube formation assay showed that the tube structure was more in 1 and 4 ATU/mL groups than in 7 ATU/mL group and control group, and in 4 ATU/mL group than in 1 ATU/mL group, showing significant differences (P<0.05). There was no significant difference between 7 ATU/mL group and control group (P>0.05). The results of immunofluorescence staining showed that compared with control group, the Notch1 expression was higher in 1 and 4 ATU/mL groups and lower in 7 ATU/mL group; and there was significant difference between 4 and 7 ATU/mL groups and control group (P<0.05). The VEGF expression was higher in 1, 4, and 7 ATU/mL groups than in control group, in 4 ATU/mL group than in 1 and 7 ATU/mL groups, showing significant differences (P<0.05). Conclusion Natural hirudin can promote angiogenesis at low and medium concentrations, but suppress angiogenesis at high concentrations. Its mechanism may be related to the VEGF-Notch signal pathway.
Objective To observe the effects of overexpression of polypyrimidine tract binding protein-associated splicing factor (PSF) on the endoplasmic reticulum (ER) oxidative stress damage of human retinal microvascular endothelial cells (hRMEC) under high concentration of 4-hydroxynonenal (4-HNE). MethodsThe logarithmic growth phase hRMEC cultured in vitro was divided into normal group, simple 4-HNE treatment group (simple 4-HNE group), empty plasmid combined with 4-HNE treatment group (Vec+4-HNE group), and PSF high expression combined with 4-HNE treatment group (PSF+4-HNE group). In 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group cell culture medium, 10 μmol/L 4-HNE was added and stimulated for 12 hours. Subsequently, the Vec+4-HNE group and PSF+4-HNE group were transfected with transfection reagent liposome 2000 into pcDNA empty bodies and pcDNA-PSF eukaryotic expression plasmids, respectively, for 24 hours. Flow cytometry was used to detect the effects of 4-HNE and PSF on cell apoptosis. The effect of PSF overexpression on the expression of reactive oxygen species (ROS) in hRMEC was detected by 2', 7'-dichlorodihydrofluorescein double Acetate probe. Western blot was used to detect ER oxide protein 1 (Ero-1), protein disulfide isomerase (PDI), C/EBP homologous transcription factor (CHOP), glucose regulatory protein (GRP) 78, protein kinase R-like ER kinase (PERK)/phosphorylated PERK (p-PERK), and Eukaryotic initiation factor (eIF) 2α/the relative expression levels of phosphorylated eIF (peIF) and activated transcription factor 4 (ATF4) proteins in hRMEC of normal group, 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group. Single factor analysis of variance was performed for inter group comparison. ResultsThe apoptosis rates of the simple 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group were (22.50±0.58)%, (26.93±0.55)%, and (11.70±0.17)%, respectively. The intracellular ROS expression levels were 0.23±0.03, 1.60±0.06, and 0.50±0.06, respectively. The difference in cell apoptosis rate among the three groups was statistically significant (F=24.531, P＜0.05). The expression level of ROS in the Vec+4-HNE group was significantly higher than that in the simple 4-HNE group and the PSF+4-HNE group, with a statistically significant difference (F=37.274, P＜0.05). The relative expression levels of ER Ero-1 and PDI proteins in the normal group, simple 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group were 1.25±0.03, 0.45±0.03, 0.63±0.03, 1.13±0.09, and 1.00±0.10, 0.27±0.10, 0.31±0.05, and 0.80±0.06, respectively. The relative expression levels of CHOP and GRP78 proteins were 0.55±0.06, 1.13±0.09, 0.90±0.06, 0.48±0.04 and 0.48±0.04, 1.25±0.03, 1.03±0.09, 0.50±0.06, respectively. The relative expression levels of Ero-1 (F=43.164), PDI (F=36.643), CHOP (F=42.855), and GRP78 (F=45.275) proteins in four groups were compared, and the differences were statistically significant (P＜0.05). Four groups of cells ER p-pERK/pERK (F=35.755), peIF2 α/ The relative expression levels of eIF (F=38.643) and ATF4 (F=31.275) proteins were compared, and the differences were statistically significant (P＜0.05). ConclusionPSF can inhibit cell apoptosis and ROS production induced by high concentration of 4-HNE, and its mechanism is closely related to restoring the homeostasis of ER and down-regulating the activation level of PERK/eIF2α/ATF4 pathway.
ObjectiveTo compare the different effects of ubiquitin(UB) on human umbilical vein endothelial cells (HUVECs) and macrophages under normal circumstances,and analyze whether UB could protect HUVECs from lipopolysaccharide(LPS) induced injury.
MethodsThe morphologic changes of HUVECs in vitro with up-rising concentrations of UB interventions were observed. HUVECs and human macrophages in vitro were divided into 4 groups according to UB concentration (0.01 μg/mL,0.1 μg/mL, 1 μg/mL, and 10 μg/mL). Supernatant and cells of each group were collected in 24 h after UB intervention. The levels of TNF-α and VCAM-1 in supernatant were measured by ELISA while NF-κB protein level in cells was detected by Western blot. HUVECs were divided into a LPS group(LPS 10 μg/mL) and an UB+LPS group(UB 0.1 μg/mL,LPS 10 μg/mL). The supernatant of the two groups were collected in 8,16 and 24 h after LPS and UB intervention. The levels of TNF-α and VCAM-1 in supernatant were measured by ELISA.
ResultsThe injury of HUVECs got worse with the ascending concentrations of UB.At the concentration of 50 μg/mL,UB induced HUVECs got ballooned and died massively. With the increase of UB concentration,the levels of TNF-α and VCAM-1 in HUVECs' supernatant ascended firstly and then descended,while those in human macrophages' supernatant ascended gradually. zHowever,the tendency of the NF-κB protein level in the two kinds of cells was similar when the concentration of UB increased.At the consentration of 0.1 μg/mL or 1 μg/mL,ubiquitin induced NF-κB protein level obviously increased.At the concentration of 0.01 μg/mL or 10 μg/mL,UB induced the protein level was similar with those of the control group and even decreased slightly. There was no significant difference in TNF-α or VCAM-1 levels at each time point between the LPS group and the UB+LPS group.
ConclusionsUB injuries HUVECs obviously at a low concentration but injuires human macrophages at much higher concentraton. UB can not protect HUVECs from LPS-induced injury in vitro.
ObjectiveTo explore the significance of continuous surveillance of anti-endothelial cell antibody (AECA) in patients with chronic obstructive pulmonary disease (COPD) in one year.MethodsThirty-six patients with acute exacerbation of COPD and 93 patients with stable COPD were selected from Guizhou Provincial People's Hospital from October 2019 to February 2020, thirty healthy people in the same period were selected as normal control group. In the stable phase group, >386.17 pg/mL was included in the higher group, and <386.17 pg/mL was included in the lower group according to the AECA median (386.17 pg/mL). According to the grouping criteria, the patient with the AECA median was omitted, the sample size of AECA higher group and lower group accounted for 46 cases, respectively. AECA test, lung function examination, the number of acute exacerbations in the past 1 year and MMRC score were performed for each group; At the same time, all the above contents were followed up dynamically.Results1. Comparison of AECA levels among the three groups: the acute exacerbation COPD group was higher than the stable phase group and the normal control group, and the stable phase group was higher than the normal control group, with statistical significance (all P<0.05). 2. Overall comparison of related indicators before and after follow-up in COPD stable period group: AECA level was higher than baseline after follow-up, and the follow-up after 12 months was higher than that after 6 months; After 12 months, forced expiratory volume in one second (FEV1), the ratio of FEV1 to forced vital capacity (FVC), and FEV1%pred were all lower than baseline, and the first two indexes were lower than those after 6 months follow-up. The number of acute exacerbations and mMRC score after 12 months were higher than that after 6 months follow-up, with statistical significance (all P<0.05). 3. Comparison of related indicators after follow-up between the higher and lower AECA groups: Follow-up after 12 months showed that AECA, the number of acute exacerbations and mMRC score in the higher AECA group were all higher than those in the lower AECA group at the same period, and the number of acute exacerbations and MMRC score in the higher AECA group were higher than those in the lower AECA group at 6-month follow-up. The FEV1, FEV1%pred and FEV1/FVC of the higher AECA group followed up after 12 months were lower than those of the lower AECA group at the same period, and the FEV1 and FEV1%pred of the higher AECA group followed up after 6 months were lower than those of the lower AECA group at the same period, and all the differences were statistically significant (all P<0.05).ConclusionAbnormality of AECA expression in COPD may be associated with continued decline in lung function, number of acute exacerbations in the previous 1 year, and increased mMRC score, and therefore may be associated with continued progression.
Objective To develop a new method for a tissue engineered vascular graft by combining endothelial cells and an acelluarized allogenic matrix. Methods Acellularized matrix tubes were obtained by a 0.1% trypsin and 0 02% EDTA solution for 24 hours and 1% Triton X 100 for 176 hours, respectively. Endothelial cells were isolated from alloaorta and expanded in vitro. Finally, the inner surface of acellularized matrix was reseeded with endothelial cells. Acellularity and reseeding were analysed by light microscopy and scanning electron microscopy. Results The acellularization procedure resulted in an almost complete removal of the original cells and the loose three-dimensional (3D) matrix. The acellular matrix could be reseeded with expanded endothelial cells in vitro, and endothelial cells had the potential of spread and proliferation. Conclusion Acellular matrix produces by Tritoon X-100 and trypsin possesses satisfactory biocompatibility for allogenic endothelial cell. Vascular grafts can be generated in vitro by a combination of endothelial cells and allogenic acelluarized matrix.
Objective To analyze the expressions of galectin-3， human bone marrow endothelial cell-1 （HBME-1），cytokeratin （CK）19， and RET in benign and malignant thyroid tumor and to discuss their clinical significances. Methods The clinicopathologic and immunohistochemical staining data of 131 patients with benign and malignant thyroid tumor were analyzed retrospectively， including 45 patients with malignant thyroid tumor， 86 patients with benign thyroidtumor. The expressions of galectin-3， HBME-1， CK19， and RET in the benign and malignant thyroid tumor were detectedby immunohistochemical staining. Results The positive expression rates of the galectin-3， HBME-1， CK19， and RET in the malignant thyroid tumor were 97.8% （44/45）， 88.9% （40/45）， 100% （45/45）， and 71.1% （32/45）， respectively，which in the benign thyroid tumor were 9.3% （8/86）， 12.8% （11/86）， 37.2% （32/86）， and 8.1% （7/86）， respectively， the differences were statistically significant （P＜0.05）. The diagnostic sensitivity， specificity， and accordance rates were 97.8 %， 90.7%， and 93.1% for the galectin-3， respectively；88.9%， 87.2%， and 87.8% for the HBME-1， respec-tively；100%， 62.8%， and 75.6% for the CK19， respectively；71.1%， 91.9%， and 84.7% for the RET， respectively. Conclusions The expression levels of galectin-3， HBME-1， CK19， and RET in malignant thyroid tumor are significantly higher than those in benign thyroid tumor. Galectin-3， HBME-1， CK19， and RET can be important factors for identifying the benign and malignant tumor and their biological behaviors. Galectin-3 has a high reference value in the diagnosis of thyroid carcinoma.
