The aim of the study is to identify the effects and underlying mechanisms of visfatin on inflammation and necroptosis in vascular endothelial cells. Human umbilical vein endothelial cells (HUVECs) were stimulated with visfatin or pretreated with Polyinosinic acid (LOX-1 inhibitor). By using the Western blot, RT-PCR, immunocytochemistry, enzyme-linked immunosorbent assay (ELISA), MTT and flow cytometry technique, the occurrence of inflammation and necroptosis in HUVECs were evaluated. Our results showed that 100 ng/mL visfatin significantly increased the mRNA and protein expression of monocyte chemotactic protein 1 (MCP-1) and LOX-1 after 24 hours’ treatment in HUVECs. However, pretreatment with Polyinosinic acid could significantly reduce the expression of MCP-1 compared with visfatin group. Additionally, 100 ng/mL visfatin could induce the production of necrotic features and increase the mRNA expression of BMF (one of the markers of necroptosis), while pretreating with Polyinosinic acid markedly downregulated the mRNA expression of BMF gene and promoted the cell proliferation. These results indicate that visfatin might induce inflammation and necroptosis via LOX-1 in HUVECs, suggesting that visfatin plays a central role in the development of atherosclerosis.
OBJECTIVE: To elongate the proliferation life-span of human umbilicus vein endothelial cell (HUVEC). METHODS: We synthesized the human telomerase reverse transcriptase mRNA (hTERT mRNA) by in vitro transcription, then transferred the hTERT mRNA into HUVEC in quicent stage by lipofect introduction. RESULTS: Telomerase expressed transiently in HUVEC, and the cell life-span was elongated for 7 population doublings. CONCLUSION: Telomerase can be reconstructed controllably and transiently in HUVEC by hTERT mRNA introduction, this method has the potential to be used to elongate the lifespan of cells cultured in vitro.
ObjectiveTo investigate whether exosomes derived from miR-27a-overexpressing human umbilical vein endothelial cells (HUVECs)—exo (miR-27a) can promote bone regeneration and improve glucocorticoids (GC) induced osteonecrosis of femoral head (ONFH) (GC-ONFH).MethodsThe exo (miR-27a) were intended to be constructed and identified by transmission electron microscopy, nanoparticle tracking analysis, Western blot, and real-time fluorescent quantitative PCR (qRT-PCR). qRT-PCR was used to evaluate the effect of exo (miR-27a) in delivering miR-27a to osteoblasts (MC3T3-E1 cells). Alkaline phosphatase staining, alizarin red staining, and qRT-PCR were used to evaluate its effect on MC3T3-E1 cells osteogenesis. Dual-luciferase reporter (DLRTM) assay was used to verify whether miR-27a targeting Dickkopf WNT signaling pathway inhibitor 2 (DKK2) was a potential mechanism, and the mechanism was further verified by qRT-PCR, Western blot, and alizarin red staining in MC3T3-E1 cells. Finally, the protective effect of exo (miR-27a) on ONFH was verified by the GC-ONFH model in Sprague Dawley (SD) rats.ResultsTransmission electron microscopy, nanoparticle tracking analysis, Western blot, and qRT-PCR detection showed that exo (miR-27a) was successfully constructed. exo (miR-27a) could effectively deliver miR-27a to MC3T3-E1 cells and enhance their osteogenic capacity. The detection of DLRTM showed that miR-27a promoted bone formation by directly targeting DDK2. Micro-CT and HE staining results of animal experiments showed that tail vein injection of exo (miR-27a) improved the osteonecrosis of SD rat GC-ONFH model.Conclusionexo (miR-27a) can promote bone regeneration and protect against GC-ONFH to some extent.
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.
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.
Objective To investigate the biological response and chemotaxis of endothel ial cells on template materials with different protein concentrations on the same surface, to provide the evidence for deep understanding of chemical induced cell motil ity. Methods Microcontact printing technique was employed to fabricate template materials with four different concentrations of collagen (50, 100, 200, 300 μg/mL) on the same substrate. Scanning electron microscopy was employed to characterize the qual ity of polydimethylsiloxane (PDMS) stamp. Confocal laser scanning microscopy (CLSM) was util ized to characterize the absorption of different concentrations of FITC conjugated collagen (50, 100, 200, 300 μg/mL) on the substrates surfaces. Software was used to analyze the fluorescence intensity of adsorbed protein on the substrates. Albumin was then used to block the substrates for cell culture of human umbil ical vein endothel ial cells (hUVEC). Substrates with no collagen adsorption were used as control samples. The influence of different concentrations of collagen on the prol iferation of hUVEC was investigated via MTT assay at 6, 24, 48 and 72 hours of culture. The cytoskeletal structures of cells were characterized by CLSM. The cell’ s migration speed and absolute displacement were measured by path measurement of single cell after 24 hours of culture. Results Fabricated PDMS stamps with complete pattern were flat. Template substrates were fully covered with evenly distributed collagen protein. The fluorescence intensities were 38.51 ± 1.63, 55.21 ± 3.88, 73.17 ± 3.59, and 80.95 ± 1.12 in adsorbed FTIC conjugated collagen with 50, 100, 200 and 300 μg/mL, respectively. Endothel ial cells spread better on various substrates coated with collagen than those of control samples. The prol iferation of endothel ial cells on collagen coated substrateswas significantly higher than that of control group (P lt; 0.05). With collagen concentration increasing from 50 µg/mL to 300µg/mL, the prol iferation abil ities and absolute displacements of endothel ial cells significantly increased (P lt; 0.05). Except for the group with 300 μg/mL, the migration speed of endothel ial cells on collagen coated substrates was significantly lower (P lt; 0.05) than that of control group. However, the migration speed of endothel ial cells on collagen coated substrates significantly increased (P lt; 0.05) along with collagen concentration increasing from 50 µg/mL to 300 µg/mL. Conclusion It is feasible to acquire domains with different protein concentrations on the same substrate using microcontact printing technique for investigating cell’s chemotaxis.
Objective To investigate the effects of the MKN-45 gastric cancer cell exosomes carrying microRNA-552 (miR-552) on the proliferation, migration, and angiogenesis of human umbilical vein endothelial cells (HUVEC). Methods ① The MKN-45 cells were divided into MKN-45 blank control group (no transfection), MKN-45 miR-552 inhibitor group [transfection of plasmid inhibiting mir-552 expression (mir-552 inhibitor plasmid)], and MKN-45 negative control group [transfection of negative control plasmid (empty plasmid)], the exosomes were extracted, purified, and identified. Western blotting was used to detect the protein expression of exosomal markers [CD63, CD9, and tumor susceptibility gene 101 (TSG101)]. ② The HUVEC cells were divided into HUVEC control group (added PBS), HUVEC-exosome group (co-cultured with exosomes of MKN-45 cell), HUVEC-negative control exosome group (co-cultured with exosomes of MKN-45 cell transfected with negative control plasmid), and HUVEC-miR-552 inhibitor exosome group (co-cultured with exosomes of MKN-45 cell transfected with miR-552 inhibitor plasmid), exosomes tracing experiment was used to detect whether exosomes entered HUVEC cells. Real-time fluorescent quantitative PCR method was used to detect the expression of miR-552, the MTT method was used to detect the proliferation of HUVEC cells, the Transwell chamber method was used to detect the migration of HUVEC cells, the angiogenesis test was used to detect the angiogenesis ability. Results This study successfully extracted exosomes from MKN-45 gastric cancer cells. Observed by transmission electron microscope, the exosomes were all round or elliptical, with a diameter of 100–150 nm, and the exosomal vesicle structure could be seen. Western blotting detection showed that the surface markers of exosomes (CD63, CD9, and TSG101 protein) were expressed in exosomes. The results of the tracing experiment showed that exosomes derived from MKN-45 cells were successfully internalized by HUVEC cells. After MKN-45 cells were transfected with miR-552 inhibitor plasmid, compared with the MKN-45 blank control group and MKN-45 negative control group, the relative expression level of miR-552 in the exosomes decreased (P<0.05). Compared with the HUVEC control group, the cell proliferation rate at 24, 48 and 74 h increased, as well as number of migration, tubule formation nodes, and relative expression level of miR-552 in the HUVEC-exosomes group increased (P<0.05). Compared with the HUVEC-negative control exosome group, the cell proliferation rate at 24, 48 and 74 h decreased, as well as the number of migration, tubule formation nodes, and relative expression level of miR-552 in the HUVEC-miR-552 inhibitor exosome group decreased (P<0.05). Conclusion The exosomes of gastric cancer cells carrying miR-552 can significantly promote the proliferation, migration, and angiogenesis of HUVEC cells.
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 construct a lentiviral vector-mediated gene-targeted small interfering RNA (siRNA) vector to vascular endothelial growth factor (VEGF), and choose the RNAi with the highest silence efficiency to VEGFA gene. MethodsThree kinds of VEGFA gene-targeted hairpin siRNA was designed (KD1, KD2, KD3), then two complementary oligo nucleotide strand were synthesized and inserted into pGCSIL-GFP vector. After annealing, the recombined vector pGCSIL-GFP-siVEGFA was gotten, which was digested by restrictive enzyme and sequenced, and was co-transfected with the pHelper 1.0 and pHelper 2.0 into 293T cells by Lipofectamine 2000. After that, the new vector was transfected into human umbilical vein endothelial cells (HUVECs), and the mRNA expression level of VEGFA gene in cells was detected by RT-PCR. Then we compared the mRNA expression level of VEGFA gene of the 3 groups. ResultspGCSIL-GFP-siVEGFA was built successfully, and all the siRNA could silence the expression of VEGFA mRNA in the HUVECs, and the relative expressions of VEGFA mRNA to the control group were 0.614±0.043 (KD1), 0.334±0.030 (KD2), and 0.201±0.015 (KD3) respectively. ConclusionWe've successfully constructed the siRNA vector for VEGFA mRNA, which can obviously suppress the expression of VEGFA mRNA.
Objective To investigate the effect of keratin 17 (K-17) on the migration, prol iferation and tube formation of human umbil ical vein endothel ial cell (HUVEC), and to real ize the role of K-17 in angiogenesis. Methods After HUVEC were cultured in DMEM medium supplemented with 10%FBS overnight, K-17-siRNA-mixture (experimental group) and Ncontrol-siRNA-mixture (negative control group) were added into HUVEC, respectively, by Lipofectamine 2000 transfection assay, and the final concentration of the siRNA was 50 nmol/L. Lipofectamine 2000 alone was used as the control. After the cells were cultured for 36 hours, the cell prol iferation abil ity was detected by cell counting. After 30-hour culture, the cell’s abil ities of migration and differentiation to tube were detected by 24-well Mill icell units and the collagen gel assay, respectively. In addition, non-siRNA-treated HUVEC were cultured for 24 hours in DMEM medium supplemented with 10%FBS (group A), 2%FBS (group B) and 2%FBS+10 ng/mL bFGF (group C), respectively, and then the expression of K-17 in HUVEC was detected by RT-PCR and Western blot. Results After the treatment with K-17-siRNA for 36 hours, HUVEC exhibited no significant difference in the prol iferation, compared with both control and negative control groups (P gt; 0.05). After transfected with K-17-siRNA for 30 hours, the number of HUVEC in the experimental group which migrated from the upper chamber to the lower chamber of Mill icell wells within 24 hours (3719.0 ± 319.0) was smaller than both control (7 437.5 ± 212.0) and negative control (7 356.3 ± 795.7) groups, with significant difference (P lt; 0.01). However, there was no significant difference between the control group and the negative control group (P gt; 0.05). After HUVEC were transfected with K-17- siRNA for 30 hours, the number of tubes in the experimental group, the negative control group and the control group in 24 hours was (1.1 ± 0.5), (3.6 ± 0.5) and (3.2 ± 0.6) per field, respectively. The experimental group was significantly different from both control and negative control groups (P lt; 0.01), and there was no significant difference between the negative control group and the control group (P gt; 0.05). The expression of K-17 protein in HUVEC in groups A, B and C was 0.25 ± 0.02, 0.08 ± 0.01 and 0.72 ± 0.03, respectively. There was significant difference among these three groups (P lt; 0.01). Conclusion K-17 has no impact on cell prol iferation, but may augment endothel ial cell migration, which may facil itate angiogenesis.