Objective To investigate the role and relative mechanism of stromal cell derived factorl (SDF-1) secreted by nucleus pulposus cells (NPCs) on the proliferation of vascular endothelial cells (VECs). Methods The NPCs were isolated from the degenerated disc specimens after discectomy. NPCs at passage 1 were transfected with lentivirus-mediated SDF-1 over-expression; transfected and untransfected NPCs at passage 2 were cultured in the three-dimensional alvetex® scaffold, then they were co-cultured with HMEC-1 cells. The morphology of NPCs was observed by scanning electron microscope (SEM), and the apoptosis of HMEC-1 cells was detected by Annexin V/propidiumiodide staining after 72 hours co-culutre. The proliferation of HMEC-1 cells was detected by cell counting kit 8 at 12, 24, 48, and 72 hours in transfected group and untransfected group, respectively. ELISA was used to measure the vascular endothelial growth factor (VEGF) expression level. The virus transfection efficiency and relative Akt pathway were determined by Western blot. Results The NPCs maintained cell phenotype and secreted much extracellular matrix in three-dimensional-culture by SEM observation. In the co-culutre system, after NPCs were transfected with SDF-1 over-expression lentivirus, the proliferation of HMEC-1 cells was significantly increased, while the apoptosis was decreased obviously. The ELISA results demonstrated that the amount of VEGF was remarkably increased in the culture medium. Furthermore, SDF-1 promoted the up-regulation of phosphorylate Akt expression; after inhibition of Akt expression by GSK690693, the proliferation rate of VECs decreased significantly. Conclusion Over-expression of SDF-1 by NPCs is beneficial for VECs proliferation, which is involved in SDF-1-Akt signalling pathway.
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.
Coronary atherosclerotic heart disease is a serious threat to human life and health. In recent years, the main treatment for it is to implant the intravascular stent into the lesion to support blood vessels and reconstruct blood supply. However, a large number of experimental results showed that mechanical injury and anti-proliferative drugs caused great damage after stent implantation, and increased in-stent restenosis and late thrombosis risk. Thus, maintaining the integrity and normal function of the endothelium can significantly reduce the rate of thrombosis and restenosis. Stem cell mobilization, homing, differentiation and proliferation are the main mechanisms of endothelial repair after vascular stent implantation. Vascular factor and mechanical microenvironmental changes in implanted sites have a certain effect on re-endothelialization. In this paper, the process of injury caused by stent implantation, the repair mechanism after injury and its influencing factors are expounded in detail. And repairing strategies are analyzed and summarized. This review provides a reference for overcoming the in-stent restenosis, endothelialization delay and late thrombosis during the interventional treatment, as well as for designing drug-eluting and biodegradation stents.
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.
Objective To observe the effect of high expression of polypyrimidine tract-binding protein-associated splicing factor (PSF) on low concentration of 4-hydroxynonenal (4-HNE) induced human retinal microvascular endothelial cells (HRMECs), and explore the possible mechanism. MethodsThe HRMECs cultured in vitro were divided into 4-HNE treated group, PSF overexpression group combined with 4-HNE group (PSF+4-HNE group), PSF overexpression+ML385 treatment combined with 4-HNE group (PSF+ML385+4-HNE group), and 4-HNE induced PSF overexpression group with LY294002 pretreatment (LY294002+4-HNE+PSF group). Cell culture medium containing 10 μmmol/L 4-HNE was added into 4-HNE treatment group, PSF+4-HNE group, PSF+ML385+4-HNE group for 12 hours to stimulate oxidative stress. 1.0 μg of pcDNA-PSF eukaryotic expression plasmid were transfected into PSF+4-HNE group and PSF+ML385+4-HNE group to achieve the overexpression of PSF. Also cells were pretreated with ML385 (5 μmol/L) for 48 hours in the PSF+ML385+4-HNE group, meanwhile within the LY294002+4-HNE+PSF group, after pretreatment with LY294002, cells were treated with plasmid transfection and 4-HNE induction. Transwell detects the migration ability of PSF to HRMECs. The effect of PSF on the lumen formation of HRMECs was detected by using Matrigel in vitro three-dimensional molding method. Flow cytometer was used to detect the effect of PSF overexpression on reactive oxygen (ROS) level in HRMECs. Protein immunoblotting was used to detect the relative expression of PSF, nuclear factor E2 related factor 2 (Nrf2), heme oxygenase-1 (HO-1) protein, and phosphoserine threonine protein kinase (pAkt) protein. The comparison between the two groups was performed using a t-test. ResultsThe number of live cells, migrating cells, and intact lumen formation in the 4-HNE treatment group and the PSF+4-HNE group were 1.70±0.06, 0.80±0.13, 24.00±0.58, 10.00±0.67, and 725.00±5.77, 318.7±12.13, respectively. There were significant differences in the number of live cells, migrating cells, and intact lumen formation between the two groups (t=12.311, 15.643, 17.346; P＜0.001). The results of flow cytometry showed that the ROS levels in the 4-HNE treatment group, PSF+4-HNE group, and PSF+ML385+4-HNE group were 816.70±16.67, 416.70±15.44, and 783.30±17.41, respectively. There were statistically significant differences between the two groups (t=16.311, 14.833, 18.442; P＜0.001). Western blot analysis showed that the relative expression levels of pAkt, Nrf2, and HO-1 proteins in HRMECs in the 4-HNE treatment group, PSF+4-HNE group and LY294002+4-HNE+PSF group were 0.08±0.01, 0.57±0.04, 0.35±0.09, 0.17±0.03, 1.10±0.06, 0.08±0.11 and 0.80±0.14, 2.50±0.07, 0.50±0.05, respectively. Compared with the PSF+4-HNE group, the relative expression of pAkt, Nrf2, and HO-1proteins in the LY294002+4-HNE+PSF group decreased significantly, with significant differences (t=17.342, 16.813, 18.794; P＜0.001). ConclusionPSF upregulates the expression of HO-1 by activating the phosphatidylinositol 3 kinase/Akt pathway and inhibits cell proliferation, migration, and lumen formation induced by low concentrations of 4-HNE.
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.
ObjectiveTo observe the effect of interleukin-8 (IL-8) on the adhesion and migration of retinal vascular endothelial cells (RCEC). MethodsA cell experiment. Human RCEC (hRCEC) was divided into normal control group (N group), advanced glycation end product (AGE) treatment group (AGE group), and AGE-induced combined IL-8 antagonist SB225002 treatment group (AGE+SB group). The effect of AGE on IL-8 expression in hRCEC was observed by Western blot. The effect of SB225002 on hRCEC migration was observed by cell scratch assay. The effects of SB225002 on leukocyte adhesion and reactive oxygen species (ROS) on hRCEC were detected by flow cytometry. Student-t test was performed between the two groups. One-way analysis of variance was performed among the three groups. ResultsCompared with group N, the expression level of IL-8 in cells of AGE group was significantly increased, with statistical significance (t=25.661, P＜0.001). Compared with N group and AGE+SB group, cell mobility in AGE group was significantly increased (F=29.776), leukocyte adhesion number was significantly increased (F=38.159, 38.556), ROS expression level was significantly increased (F=22.336), and the differences were statistically significant (P＜0.05). ConclusionIL-8 antagonist SB225002 may down-regulate hRCEC adhesion and migration by inhibiting ROS expression.
ObjectiveTo explore the effect of Kaempferol on bone microvascular endothelial cells (BMECs) in glucocorticoid induced osteonecrosis of the femoral head (GIONFH) in vitro. MethodsBMECs were isolated from cancellous bone of femoral head or femoral neck donated voluntarily by patients with femoral neck fracture. BMECs were identified by von Willebrand factor and CD31 immunofluorescence staining and tube formation assay. The cell counting kit 8 (CCK-8) assay was used to screen the optimal concentration and the time point of dexamethasone (Dex) to inhibit the cell activity and the optimal concentration of Kaempferol to improve the inhibition of Dex. Then the BMECs were divided into 4 groups, namely, the cell group (group A), the cells treated with optimal concentration of Dex group (group B), the cells treated with optimal concentration of Dex+1 μmol/L Kaempferol group (group C), and the cells treated with optimal concentration of Dex+5 μmol/L Kaempferol group (group D). EdU assay, in vitro tube formation assay, TUNEL staining assay, Annexin Ⅴ/propidium iodide (PI) staining assay, Transwell migration assay, scratch healing assay, and Western blot assay were used to detect the effect of Kaempferol on the proliferation, tube formation, apoptosis, migration, and protein expression of BMECs treated with Dex. ResultsThe cultured cells were identified as BMECs. CCK-8 assay showed that the optimal concentration and the time point of Dex to inhibit cell activity was 300 μmol/L for 24 hours, and the optimal concentration of Kaempferol to improve the inhibitory activity of Dex was 1 μmol/L. EdU and tube formation assays showed that the cell proliferation rate, tube length, and number of branch points were significantly lower in groups B-D than in group A, and in groups B and D than in group C (P<0.05). TUNEL and Annexin V/PI staining assays showed that the rates of TUNEL positive cells and apoptotic cells were significantly higher in groups B-D than in group A, and in groups B and D than in group C (P<0.05). Scratch healing assay and Transwell migration assay showed that the scratch healing rate and the number of migration cells were significantly lower in groups B-D than in group A, and in groups B and D than in group C (P<0.05). Western blot assay demonstrated that the relative expressions of Cleaved Caspase-3 and Bax proteins were significantly higher in groups B-D than in group A, and in groups B and D than in group C (P<0.05); the relative expressions of matrix metalloproteinase 2, Cyclin D1, Cyclin E1, VEGFA, and Bcl2 proteins were significantly lower in groups B-D than in group A, and in groups B and D than in group C (P<0.05). Conclusion Kaempferol can alleviate the damage and dysfunction of BMECs in GIONFH.
ObjectiveTo observe the effects of four prostaglandin E2 (PGE2) receptors (EP1-4R) on the activation of inflammasomes and cell damage in human retinal microvascular endothelial cells (hRMEC) in a high glucose environment.MethodsThe hRMEC were divided into normal group and high glucose group, and they were cultured in Dulbecco modified Eagle medium containing 5.5 and 30.0 mmol/L glucose, respectively. Flow cytometry was used to observe the apoptosis rate of the high glucose group and the normal group; enzyme chain immunosorbent assay (ELISA) was used to detect the level of PGE2 in the culture supernatant of hRMEC cells. Western blot was used to detect the protein expression of cyclooxyganese (COX2) and EP1-4R in hRMEC. Real-time fluorescent quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression of EP1-4R mRNA in hRMEC. After 72 h of culture, the cells in the high glucose group were divided into control group, PGE2 group, EP1-4R agonist group, PGE2+EP1-4R inhibitor group, and dimethylsulfoxide group. According to the group, each group was given the corresponding agonist or inhibitor to continue the culture for 24 h. QRT-PCR was used to detect the expression of nucleotide-binding oligomerization structure-like receptor protein (NLRP3) and pro-interleukin (IL)-1β mRNA in each group of cells. ELISA was used to detect the content of IL-1β and lactic dehydrogenase (LDH) in the cell culture supernatant. Western blot was used to detect the expression of cleaved Caspase-1 in each group of cells. At the same time, hRMEC in a high glucose environment was given IL-1β stimulation for 24 h, and the activity of LDH in the supernatant of the cell culture medium was detected.ResultsThe apoptotic rate, COX2 protein expression, and PGE2 protein content in hRMEC in the high glucose group were significantly higher than those in the normal group, and they were time-dependent. Compared with the normal group, the expression levels of EP1R, EP2R, EP4R protein and mRNA in hRMEC in the high glucose group were higher than those in the normal group (P＜0.05). Compared with the control group, PGE2 group (t=4.627, P＜0.01), EP1-4R agonist group (t=3.889, 3.583, 2.445, 3.216; P＜0.05) hRMEC NLRP3 mRNA expression level was significantly increased; the expression level of pro-IL-1β mRNA increased, however the difference was not statistically significant (PGE2 group: t=1.807, P＞0.05; EP1-4R agonist group: t=1.807, 1.477, 0.302, 1.926, P＞0.05). Compared with the PGE2 group, the expression of NLRP3 mRNA in hRMEC in the PGE2+EP2R inhibitor group was significantly reduced (t=2.812, P＜0.05); the expression of pro-IL-1β mRNA in hRMEC in the PGE2+EP3R inhibitor group was significantly increased (t=4.113, P＜0.01). The protein content of IL-1β in the cell culture supernatant of the PGE2 group, EP1R agonist group and EP2R agonist group was significantly higher than that of the control group (t=5.155, 4.136, 4.817; P＜0.01). Compared with PGE2 group, the protein content of IL-1β in the cell culture supernatant of the PGE2+EP2R inhibitor group and the PGE2+EP4R inhibitor group were significantly lower than that of the PGE2 group (t=1.964, 4.765; P＜0.05). The expression of cleaved Caspase-1 in hRMEC in the PGE2 group and EP2R agonist group was significantly higher than that in the control group (t=5.332, 4.889; P＜0.05). The expression of cleaved Caspase-1 in hRMEC in the PGE2+EP2R inhibitor group was significantly lower than that of the PGE2 group (t=6.699, P＜0.01). The LDH activity in the cell culture supernatant of the PGE2 group and the EP2R agonist group was significantly higher than that of the control group (t=4.908, 4.225; P＜0.05). The activity of LDH in the cell culture supernatant of the PGE2+EP2R inhibitor group was significantly lower than that of the PGE2 group (t=5.301, P＜0.01). Compared with the control group, the LDH activity in the culture supernatant of hRMEC cells in the high glucose environment was significantly increased (t=3.499, P＜0.05).ConclusionsThe four receptors of PGE2 can activate NLRP3 and its effector molecules to varying degrees. EP2R mainly mediates hRMEC damage under high glucose environment.
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.