Morphology Of Human Umbilical Vein Endothelial Cells Research Articles

A preliminary in vivo and in vitro study of endothelial cell pyroptosis in the periodontal inflammatory environment

Objective: To observe whether endothelial cells undergo pyroptosis in the inflammatory periodontal environment by using a model in vivo and in vitro, providing an experimental basis for indepth understanding of the underlying pathogenesis of periodontitis. Methods: According to the classification of periodontal diseases of 2018, gingival tissues were collected from periodontally healthy subjects and patients with stage Ⅲ-Ⅳ, grade C periodontitis, who presented Department of Oral and Maxillofacial Surgery and Department of Periodontology, School of Stomatology, The Fourth Military Medical University from April to May 2022. Immunohistochemical staining was performed to detect the expression level and distribution of gasdermin D (GSDMD), a hallmark protein of cell pyroptosis, in gingival tissues. Periodontitis models were established in each group by ligating the maxillary second molar teeth of three mice for 2 weeks (ligation group). The alveolar bone resorption was determined by micro-CT (mice without ligation treatment were used as the control group), and the colocalization of GSDMD and CD31 were quantitatively analyzed by immunofluorescence staining in gingival tissues of healthy and inflammatory mice. Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and treated with lipopolysaccharide (LPS) of Porphyromonas gingivalis (Pg) combined with adenosine triphosphate (ATP) at various concentrations of 0.5, 1.0, 2.5, 5.0, and 10.0 mg/L, respectively, and the 0 mg/L group was set as the control group at the same time. Scanning electron microscopy was used to observe the morphology of HUVECs. Western blotting was used to detect the expression of gasdermin D-N terminal domains (GSDMD-N) protein and immunofluorescence cell staining was used to detect the expression and distribution of GSDMD. Cell counting kit-8 (CCK-8) was used to detect the proliferative ability of HUVECs, and propidium iodide (PI) staining was used to detect the integrity of cell membrane of HUVECs. Results: Immunohistochemistry showed that GSDMD in gingival tissues of periodontitis was mainly distributed around blood vessels and its expression level was higher than that in healthy tissues. Micro-CT showed that alveolar bone resorption around the maxillary second molar significantly increased in ligation group mice compared with control subjects (t=8.88, P<0.001). Immunofluorescence staining showed significant colocalization of GSDMD with CD31 in the gingival vascular endothelial cells in mice of ligation group. The results of scanning electron microscopy showed that there were pores of different sizes, the typical morphology of pyroptosis, on HUVECs cell membranes in the inflammatory environment simulated by ATP combined with different concentrations of LPS, and 2.5 mg/L group showed the most dilated and fused pores on cell membranes, with the cells tended to lyse and die. Western blotting showed that the expression of GSDMD-N, the hallmark protein of cell pyroptosis, was significantly higher in 2.5 and 5.0 mg/L groups than that in the control group (F=3.86, P<0.01). Immunofluorescence cell staining showed that the average fluorescence intensity of GSDMD in 2.5 mg/L group elevated the most significantly in comparison with that in the control group (F=35.25, P<0.001). The CCK-8 proliferation assay showed that compared to the control group (1.00±0.02), 0.5 mg/L (0.52±0.07), 1.0 mg/L (0.57±0.10), 2.5 mg/L (0.58±0.04), 5.0 mg/L (0.55±0.04), 10.0 mg/L (0.61±0.03) groups inhibited cell proliferation (F=39.95, P<0.001). PI staining showed that the proportion of positive stained cells was highest [(56.07±3.22)%] in 2.5 mg/L group (F=88.24, P<0.001). Conclusions: Endothelial cells undergo significant pyroptosis in both in vivo and in vitro periodontal inflammatory environments, suggesting that endothelial cell pyroptosis may be an important pathogenic factor contributing to the pathogenesis of periodontitis.

Estrogen receptor alpha mediates 17β-estradiol, up-regulates autophagy and alleviates hydrogen peroxide-induced vascular senescence.

Atherosclerosis threatens human health by developing cardiovascular diseases, the deadliest disease world widely. The major mechanism contributing to the formation of atherosclerosis is mainly due to vascular endothelial cell (VECs) senescence. We have shown that 17β-estradiol (17β-E2) may protect VECs from senescence by upregulating autophagy. However, little is known about how 17β-E2 activates the autophagy pathway to alleviate cellular senescence. Therefore, the aim of this study is to determine the role of estrogen receptor (ER) α and β in the effects of 17β-E2 on vascular autophagy and aging through in vitro and in vivo models. Hydrogen peroxide (H2O2) was used to establish Human Umbilical Vein Endothelial Cells (HUVECs) senescence. Autophagy activity was measured through immunofluorescence and immunohistochemistry staining of light chain 3 (LC3) expression. Inhibition of ER activity was established using shRNA gene silencing and ER antagonist. Compared with ER-β knockdown, we found that knockdown of ER-α resulted in a significant increase in the extent of HUVEC senescence and senescence-associated secretory phenotype (SASP) secretion. ER-α-specific shRNA was found to reduce 17β-E2-induced autophagy, promote HUVEC senescence, disrupt the morphology of HUVECs, and increase the expression of Rb dephosphorylation and SASP. These in vitro findings were found consistent with the in vivo results. In conclusion, our data suggest that 17β-E2 activates the activity of ER-α and then increases the formation of autophagosomes (LC3 high expression) and decreases the fusion of lysosomes with autophagic vesicles (P62 low expression), which in turn serves to decrease the secretion of SASP caused by H2O2 and consequently inhibit H2O2-induced senescence in HUVEC cells.

Effects of hydrogen peroxide on endothelial function in three-dimensional hydrogel vascular model and regulation mechanism of polar protein Par3

Three-dimensional (3D) cell cultures better reflect the function of endothelial cells (ECs) than two-dimensional (2D) cultures. In recent years, studies have found that ECs cultured in a 3D luminal structure can mimic the biological characteristics and phenotypes of vascular ECs, thus making it more suitable for endothelial dysfunction research. In this study, we used a 3D model and 2D tissue culture polystyrene (TCP) to investigate the effects of cell polarity on hydrogen peroxide (H2O2)-induced endothelial dysfunction and its related mechanisms. We observed the cell morphology, oxidative stress, and barrier and endothelial function of human umbilical vein ECs (HUVECs) in 3D and 2D cultures. We then used Illumina to detect the differentially expressed genes (DEGs) in the 3D-cultured HUVEC with and without H2O2 stimulation, using clusterProfiler for Gene Ontology function enrichment analysis and Kyoto Encyclopaedia of Genes and Genomes pathway enrichment analysis of DEGs. Finally, we explored the role and mechanism of polar protein partitioning defective protein 3 (Par3) in the regulation of ECs. ECs were inoculated into the 3D hydrogel channel; after stimulation with H2O2, the morphology of HUVECs changed, the boundary was blurred, the expression of intercellular junction proteins decreased, and the barrier function of the EC layer was damaged. 3D culture increased the oxidative stress response of cells stimulated by H2O2 compared to 2D TCPs. The polarity-related protein Par3 and cell division control protein 42 were screened using bioinformatics analysis, and western blotting was used to verify the results. Par3 knockdown significantly suppressed claudin1 (CLDN1) and vascular endothelial cadherin. These results suggest that the polar protein Par3 can protect H2O2-induced vascular ECs from damage by regulating CLDN1 and VE-cadherin.

Surface Creasing-Induced Micropatterned GelMA Using Heating-Hydration Fabrication for Effective Vascularization.

Surface modification is used to modify the biomaterials for the regulation of cell culture using different approaches, such as chemical graft and mechanical treatment. However, those conventional methodologies often require precise fabrication in a high resolution involving either high cost or laborious steps to remove chemical residues that are toxic to the cells. A novel and simple method was proposed and evaluated to rapidly generate surface ceases on the gelatin methacrylate (gelMA) surface using the heating-hydration process. Human umbilical vein endothelial cells (HUVECs) were cultured on the gelMA surface. The surface binding was characterized using the RGD (Arg-Gly-Asp) antibodies and cell adhesion pattern captured by scanning electron microscopy. The effect of the heating-hydration parameters on the creasing formation was investigated. The morphology of HUVECs cultured on such micropatterned gelMA was characterized and compared. It is found that the hydration solution, gelMA mixture, and hydration rate are the major factors that influence the cracking sizes in the range from 20 to 120µm which resulted in capillary-like patterns on the gelMA surface. Low concentration of gelMA, high water concentration of cooling agent, and slow hydration rate result in the long creases, and heating of at least 60min is required for complete dehydration. Strong fluorescence was around the creases with RGD-staining. Consequently, micropatterned gelMA demonstrated good biocompatibility with endothelial cells with more than 95% cell viability and continuous cell proliferation throughout 2weeks as well as a good trace of neovascular formation. In comparison, normal gelMA surface did not exhibit RGD-fluorescent signals, and the cultured HUVECs on it were rounded with no spreading for network formation. The heating-hydration approach can successfully and easily produce the micropatterned gelMA that allows rapid and effective vascularization to potentially improve the functionalities of the tissue-engineered construct.

In vitro investigation on microstructure, bio-corrosion properties and cytotoxicity of as-extruded Mg–5Sn–xIn alloys

The microstructure, bio-corrosion properties and cytotoxicity of as-extruded Mg–5Sn–xIn (x = 0, 1, 2, 3, 4, all in wt%) alloys were investigated in vitro for biomedical applications. The results show that the microstructure of all alloys exhibits a partially recrystallized structure, and the area fraction of dynamically recrystallized (DRXed) grains increases with In addition. Mg2Sn particles are mostly precipitated at DRXed grains. Weight loss and potentiodynamic polarization measurements show that the bio-corrosion resistance of as-extruded Mg–5Sn–xIn alloys is enhanced with increasing In content as a result of cathodic reaction being hindered by indium oxide deposition on the alloy surfaces. The Mg–5Sn–4In alloy exhibits the minimum corrosion rate of 0.36 mm/y after immersion in Hank’s solution for 15 days. The cytotoxicity tests reveal that the as-extruded Mg–5Sn–xIn alloys do not induce toxicity to murine fibroblast cells (NIH3T3) and Human Umbilical Vein Endothelial Cells (HUVECs). The HUVECs morphology is ameliorated in the alloys with In addition, which is greatly associated with decreasing corrosion rate. Thus, this study uses In as an effective alloying element to tune the corrosion property of Mg–Sn based alloys with low degradation and excellent cytocompatibility.

Fabrication of PDMS microfluidic devices using nanoclay-reinforced Pluronic F-127 as a sacrificial ink

Additive manufacturing or three-dimensional (3D) printing technology is increasingly being employed in biochemical as well as clinical applications and more importantly in fabrication of microfluidic devices. However, the microfluidic community mainly relies on photolithography for fabrication of a defined mask, which is both tedious and expensive requiring clean room settings as well as limited to the generation of two-dimensional features. In this work, we 3D printed nanoclay-reinforced Pluronic ink as a sacrificial material, which exhibited shear thinning behavior and superior printability allowing the fabrication of unsupported or overhanging templates of channels with uniform diameter and circular cross-sections. To highlight the potential and effectiveness of the presented approach, we fabricated a human blood vessel-on-a-chip model with curved as well as straight channels. These channels were then lined up with human umbilical vein endothelial cells (HUVECs) and subjected to a dynamic culture for 10 d to explore the effect of shear stress on HUVEC morphology based on the location of HUVECs in the devices. Overall, we presented a highly affordable, practical and useful approach in manufacturing of polydimethylsiloxane-based devices with closed microfluidic channels, which holds great potential for a numerous applications, such as but not limited to organ-on-a-chip, microfluidics, point-of-care devices and drug screening platforms.

Tectorigenin protect HUVECs from H2O2-induced oxidative stress injury by regulating PI3K/Akt pathway

Oxidative stress injury (OSI) occurs in many cardiovascular diseases, and the OSI of endothelial cells is the main pathological basis of these diseases. Tectorigenin has an effect on oxidative stress in fibroblasts, keratinocytes, and neuroblastoma. This study attempted to reveal the effect of Tectorigenin on OSI in endothelial cells.An OSI cell model was firstly established by treating human umbilical vein endothelial cells (HUVECs) with H2O2. The H2O2-induced HUVECs were further pre-treated with Tectorigenin or PI3K inhibitor. Then the viability and apoptosis of HUVECs were evaluated using MTT, Hochest 33258 staining and TUNEL staining. Lactate dehydrogenase (LDH) leakage, enzyme activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) level were measured through colorimetric assays. The expressions of apoptosis-related factors and the activation of the PI3K/Akt pathway in HUVECs were detected by RT-qPCR or Western blot.Tectorigenin had no inhibiting effect on the viability of HUVECs at the concentrations of 0.1, 0.5, 0.5, 1, and 10 μmol/L. Tectorigenin reversed the H2O2 induced-destruction of HUVECs morphology. Tectorigenin increased the viability and decreased the apoptosis of H2O2-induced HUVECs. Tectorigenin increased Bcl-2 expression and the enzyme activities of SOD and GSH-Px, but decreased LDH leakage, MDA level, and the expressions of Bax and Cleaved Caspase-3 in H2O2-induced HUVECs. Furthermore, Tectorigenin increased the ratios of p-PI3K to PI3K and p-Akt to Akt in H2O2-induced HUVECs. PI3K inhibitor had an opposite effect of Tectorigenin on the OSI in H2O2-induced HUVECs and its effect was further reversed by Tectorigenin.Tectorigenin protected HUVECs against H2O2-induced OSI via PI3K/Akt pathway.

Co-culture of mesenchymal stem cells and human umbilical vein endothelial cells on heparinized polycaprolactone/gelatin co-spun nanofibers for improved endothelium remodeling

Endothelization of a tissue-engineered substrate is important for its application as an artificial vascular graft. Despite recent advancements in artificial graft fabrication, a graft of <5 mm is difficult to fabricate owing to insufficient endothelization that results in thrombosis after transplantation. We aimed to perform a co-culture of adipose-derived mesenchymal stem cells (MSCs) with human umbilical vein endothelial cells (HUVECs) on antithrombogenic polycaprolactone (PCL)/heparin-gelatin co-spun nanofibers to evaluate the role of co-culturing in promoting quick endothelization of vascular substrates without surface modification by growth factors or other ECM proteins that trigger the endothelization process. Using a co-axial electrospinning technique, we attempted to fabricate our scaffold balancing between mechanical properties and biocompatibility. Antithrombogenic characteristics were then imparted to the fabricated nanofiber substrate by grafting of heparin. Finally, we performed a co-culture of MSCs and HUVECs on the fabricated co-spun nanofiber substrate to obtain proper endothelization of our material under the in-vitro culture. Staining for CD-31 at seven days of culture revealed enhanced CD-31 expression under the co-culture condition; actin staining revealed healthy cobblestone HUVEC morphology, suggesting that MSCs can aid in proper endothelization. Hence, we conclude that co-culture is effective for quick endothelization of vascular substrates.

21: Mesenchymal Stem Cells Alleviated Palmitic Acid Induced Endothelial to Mesenchymal Transition in HUVEC by Secreting STC1

Background: Endothelial dysfunction (ED) is an early indicator of vascular complications in type 2 diabetes. Hyperlipidemia is believed to be a key causal factor promoting ED. Our previous study showed that mesenchymal stem cells (MSCs) were able to ameliorate palmitic acid (PA) induced ED, but the mechanisms involved are unclear. Endothelial-to-mesenchymal transition (EndMT) is demonstrated mechanistically related to ED in a variety of vascular diseases. Here we explored the effects of MSCs on PA induced EndMT and disclosed the mechanism in human umbilical vein endothelial cells (HUVECs). Methods: The primary HUVECs were treated by PA (50 μM) with or without human umbilical cord derived MSCs (UC-MSCs) for 24 h in Transwell system at a ratio of 5:1. EndMT related proteins expression were evaluated by western blot and immunofluorescence. The secretion of stanniocalcin 1 (STC1) was quantified using an ELISA kit. Recombinant STC1 (rSTC1) and siRNA targeting STC1 were used to evaluate the role of STC1 in MSCs mediated protective effects. Result: After PA treatment, the cell morphology of HUVECs changed from an endothelial-typical cobblestone-like appearance to a mesenchymal-typical spindle-shaped pattern, suggesting the occurrence of EndMT. However, coculture with MSCs alleviated the morphological change of HUVECs (Fig.1A). Western blot analysis revealed that PA significantly decreased endothelial marker CD31 and CD144 expression and increased fibroblast markers vimentin and α-SMA expression, which could be partly reversed by coculture with MSCs (Fig.B). Consistently, immunofluorescent staining for CD31 and α-SMA revealed a significant loss of CD31 and enhancement of α-SMA in PA group in comparison of control. However, MSCs effectively antagonized PA induced toxicity by increasing CD31 and decreasing α-SMA expression in HUVECs (Fig.1C). Next, we explored the underlying mechanisms focusing on the secretome of MSCs. We found that resting MSCs secreted more STC1 than HUVECs did, while, PA (50 μM) strongly stimulated MSCs to synthesize and release much more STC1 (Fig.2A). Furthermore, the cell viability of HUVECs declined to 49% of control after PA stimulation. However, the addition of rSTC1 showed similar protective effect of MSCs, and restored the cell viability to 89% (Fig.2B). rSTC1 also reversed the expression switch of EndMT- related proteins (Fig.2C). Additionally, silencing of STC1 gene by siRNA in MSCs abrogated above protective effects suggesting the critical role of STC1 in MSCs (Fig.2D-E). Conclusion: MSCs ameliorated PA-induced EndMT in HUVECs, in which the STC1 secreted by MSCs has played a critical role. National Natural Science Foundation of China (grant number 31571474 and 81370824).

Adipose tissue–derived stromal cells’ conditioned medium modulates endothelial‐mesenchymal transition induced by IL‐1β/TGF‐β2 but does not restore endothelial function

ObjectivesEndothelial cells undergo TGF‐β–driven endothelial‐mesenchymal transition (EndMT), representing up to 25% of cardiac myofibroblasts in ischaemic hearts. Previous research showed that conditioned medium of adipose tissue–derived stromal cells (ASC‐CMed) blocks the activation of fibroblasts into fibrotic myofibroblasts. We tested the hypothesis that ASC‐CMed abrogates EndMT and prevents the formation of adverse myofibroblasts.Materials and methodsHuman umbilical vein endothelial cells (HUVEC) were treated with IL‐1β and TGF‐β2 to induce EndMT, and the influence of ASC‐CMed was assessed. As controls, non‐treated HUVEC or HUVEC treated only with IL‐1β in the absence or presence of ASC‐CMed were used. Gene expression of inflammatory, endothelial, mesenchymal and extracellular matrix markers, transcription factors and cell receptors was analysed by RT‐qPCR. The protein expression of endothelial and mesenchymal markers was evaluated by immunofluorescence microscopy and immunoblotting. Endothelial cell function was measured by sprouting assay.ResultsIL‐1β/TGF‐β2 treatment induced EndMT, as evidenced by the change in HUVEC morphology and an increase in mesenchymal markers. ASC‐CMed blocked the EndMT‐related fibrotic processes, as observed by reduced expression of mesenchymal markers TAGLN (P = 0.0008) and CNN1 (P = 0.0573), as well as SM22α (P = 0.0501). The angiogenesis potential was impaired in HUVEC undergoing EndMT and could not be restored by ASC‐CMed.ConclusionsWe demonstrated that ASC‐CMed reduces IL‐1β/TGF‐β2‐induced EndMT as observed by the loss of mesenchymal markers. The present study supports the anti‐fibrotic effects of ASC‐CMed through the modulation of the EndMT process.

Effects of various doses of atorvastatin on vascular endothelial cell apoptosis and autophagy invitro.

Atorvastatin (Lipitor™) is a lipid‑lowering agent that is widely used in the treatment of cardiovascular diseases. Previous research has largely focused on its cholesterol‑lowering effects; however, a limited number of studies have investigated the actions of atorvastatin on vascular endothelial cells. In the present study, the effects of various doses of atorvastatin were investigated on human umbilical vein endothelial cells (HUVECs). HUVECs were treated with various concentrations of atorvastatin in serum‑free or serum‑containing medium, and alterations in HUVEC morphology were observed. Cell survival and necrosis rates were evaluated using sulforhodamine B and lactate dehydrogenase assays, respectively. In addition, the protein expression levels of cellular apoptosis and autophagy markers were detected using western blot analysis. The results revealed that HUVEC morphology was altered following treatment with various concentrations of atorvastatin. In addition, autophagy was demonstrated to be induced by atorvastatin treatment at all concentrations, whereas high concentrations appeared to induce apoptosis and suppress the survival of HUVECs. In conclusion, the results of the present study suggested that various doses of atorvastatin may exert differential effects on HUVECs, and high doses may suppress angiogenesis. Therefore, atorvastatin may present a novel potential anti‑tumor therapeutic strategy. However, further studies are required to fully elucidate the association between the dose of atorvastatin and its clinical outcome.

Protective effects of Schisandrin on high glucose-induced changes of RhoA and eNOS activity in human umbilical vein endothelial cells

Schisandrin, derived from the Chinese medicinal herb Schisandra chinensis, has been found to confer protective effects on circulation systems. But the underlying molecular mechanisms remain unclear. The aim of this study was to investigate the effects of a high level of glucose on RhoA and eNOS activity in human umbilical vein endothelial cells(HUVECs) and how Schisandrin plays a role in mediating these effects. To find the optimal treatment time, HUVECs were cultured at a high glucose concentration (30 mM) for different lengths of time (0, 12, 24, and 48 h). Subsequently, the cells were randomized into five groups: a normal group, a high glucose group, and three high glucose groups that were given different doses (5, 10, and 20 μM) of Schisandrin. The cells were pretreated with Schisandrin for 24 h before stimulation with high glucose. The morphology of HUVECs in the various groups was assessed under a light microscope. Immunocytochemical staining was used to detect the level of p-MYPT1 expression. The levels of RhoA activity were determined using the RhoA Activation Assay Biochem Kit. The levels of eNOS activity were examined using a nitrate reduction test. The results showed that in the high glucose group, the activity of RhoA was increased and the activity of eNOS was reduced, thus decreasing the secretion of NO. However, after pretreatment with Schisandrin (10, 20 μM), the activity of RhoA was inhibited and the activity of eNOS increased, which led to an increase in NO production compared with the high glucose group. There was no evident difference between the 5 μM Schisandrin group and the high glucose group. Taken together, these findings indicate that Schisandrin can improve the function of endothelial cells by lowering the activity of RhoA/Rho kinase and raising both the activity of eNOS and the production of NO.

The role of vascular endothelial growth factor and mesenchymal stem cells during angiogenesis

Objective: Angiogenesis is essential for bone remodeling and regeneration. We previously showed that 3 months after transplantation of mesenchymal stem cells (MSCs) into a bone defect area, significantly more regenerated bone was present on the MSC side than on the control side. On the side transplanted with MSCs, the number of blood vessels was significantly higher. Therefore, during the remodeling process, MSCs, which are necessary for regenerating bone, were involved in bone regeneration through angiogenesis in the transplanted area. In addition, MSCs produce Vascular Endothelial Growth Factor (VEGF). Therefore, we investigated the influence of differentiation of MSCs on the expression of VEGF. Methods: We investigated how changes in osteogenic differentiation of MSCs affect VEGF gene and protein expression and how co-culture with Human Umbilical Vein Endothelial Cells (HUVECs) affects gene expression in MSCs. We also determined the role MSCs play in the transplanted area, and the effects on HUVEC morphology when co-cultured with MSCs. Results: VEGF gene and protein expression in undifferentiated MSCs was higher than in differentiated MSCs. VEGF gene expression in MSCs co-cultured with HUVECs was higher than when MSCs were cultured alone. In co-cultures of MSCs and HUVECs, a lumen-like structure was observed on the 3rd day of culture, and then several luminal structures were observed later. Conclusion: MSC transplantation may contribute to angiogenesis via production of VEGF.

Enhancing the biocompatibility of the polyurethane methacrylate and off-stoichiometry thiol-ene polymers by argon and nitrogen plasma treatment

Our studies focused on improving the biocompatibility properties of two microfluidic prototyping substrates i.e. polyurethane methacrylate (PUMA) and off-stoichiometry thiol-ene (OSTE-80) polymer by Ar and N2 plasma treatment. The contact angle (CA) measurement showed that both plasma treatments inserted oxygen and nitrogen moieties increased the surface energy and hydrophilicity of PUMA and OSTE-80 polymer which corresponded to an increase of nitrogen to carbon ratios (N/C), as measured by XPS, to provide a conducive environment for cell attachments and proliferation. Under the SEM observation, the surface topography of PUMA and OSTE-80 polymer showed minimal changes after the plasma treatments. Furthermore, ageing studies showed that plasma-treated PUMA and OSTE-80 polymer had stable hydrophilicity and nitrogen composition during storage in ambient air for 15days. After in vitro cell culture of human umbilical vein endothelial cells (HUVECs) on these surfaces for 24h and 72h, both trypan blue and alamar blue assays indicated that PUMA and OSTE-80 polymer treated with N2 plasma had the highest viability and proliferation. The polar nitrogen moieties, specifically amide groups, encouraged the HUVECs adhesion on the plasma-treated PUMA and OSTE-80 surfaces. Interestingly, PUMA polymer treated with Ar and N2 plasma showed different HUVECs morphology which was spindle and cobblestone-shaped respectively after 72h of incubation. On the contrary, a monolayer of well-spread HUVECs formed on the Ar and N2 plasma-treated OSTE-80 polymers. These variable morphologies observed can be ascribed to the adherence HUVECs on the different elastic moduli of these surfaces whereby further investigation might be needed. Overall, Ar and N2 plasma treatment had successfully altered the surface properties of PUMA and OSTE-80 polymer by increasing its surface energy, hydrophilicity and chemical functionalities to create a biocompatible surface for HUVECs adhesion and proliferation.

Cytotoxic effects of docetaxel as a candidate drug of drug-eluting stent on human umbilical vein endothelial cells and the signaling pathway of cell migration inhibition, adhesion delay and shape change.

Docetaxel (DTX), a paclitaxel analogue, can efficiently inhibit proliferation of vascular smooth muscle cells and has broadly been used as an antiangiogenesis drug. However, as a candidate drug of drug-eluting stent, the effects of DTX on human umbilical vein endothelial cells (HUVECs) are still not well understood. Herein, we investigated the effects of DTX on proliferation, apoptosis, adhesion, migration and morphology of HUVECs in vitro. We found that DTX had the cytostatic and cytotoxic effects at low and high concentrations, respectively. DTX could inhibit the proliferation and migration of HUVECs, induce HUVECs apoptosis, delay HUVECs adhesion and decrease spreading area and aspect ratio of individual cells. The signaling pathway that DTX led to the migration inhibition, adhesion delay and shape change of HUVECs is the VE-cadherin mediated integrin β1/FAK/ROCK signaling pathway. The study will provide a theoretical basis for the clinical application of DTX.

Cancer cells increase endothelial cell tube formation and survival by activating the PI3K/Akt signalling pathway

BackgroundAngiogenesis is a hallmark of cancer and plays a critical role in lung cancer progression, which involves interactions between cancer cells, endothelial cells and the surrounding microenvironment. However, the gene expression profiles and the changes in the biological phenotype of vascular endothelial cells after interactions with lung cancer cells remain unclear.MethodsAn indirect transwell co-culture system was used to survey the interaction between human umbilical vein endothelial cells (HUVECs) and human lung adenocarcinoma CL1-5 cells, as well as to investigate the morphological and molecular changes of HUVECs. The differentially expressed genes (DEGs) in HUVECs after co-culture with cancer cells were identified by microarray. Moreover, a publicly available microarray dataset of 293 non-small-cell lung cancer (NSCLC) patients was employed to evaluate the prognostic power of the gene signatures derived from HUVECs.ResultsThe interaction between HUVECs and lung cancer cells changes the morphology of HUVECs, causing them to have a mesenchymal-like morphology and alter their cytoskeleton organization. Furthermore, after co-culture with lung cancer cells, HUVECs showed increased cell motility and microvessel tube formation ability and a decreased apoptotic percentage. Transcriptomic profiling of HUVECs revealed that many survival-, apoptosis- and angiogenesis-related genes were differentially expressed after interactions with lung cancer cells. Further investigations showed that the PI3K/Akt signalling pathway and COX-2 are involved in endothelial tube formation under the stimulation of lung cancer cells. Moreover, Rac-1 activation might promote endothelial cell motility through the increased formation of lamellipodia and filopodia. The inhibitors of PI3K and COX-2 could reverse the increased tube formation and induce the apoptosis of HUVECs. In addition, the gene signatures derived from the DEGs in HUVECs could predict overall survival and disease-free survival in NSCLC patients and serve as an independent prognostic factor.ConclusionsIn this study, we found that cancer cells can promote endothelial cell tube formation and survival, at least in part, through the PI3K/Akt signalling pathway and thus change the microenvironment to benefit tumour growth. The gene signatures from HUVECs are associated with the clinical outcome of NSCLC patients.

Biomaterial Surface Can Modify HUVEC Morphology and Inflammatory Response by Regulating MicroRNA Expression

Vascular inflammation is an important process which contributes to the pathogenesis of many cardiovascular diseases, such as atherosclerosis. MicroRNAs (miRNAs) have been revealed as novel regulators of vascular inflammation. Prior researches had shown that alterations in gene expression of human umbilical vein endothelial cells (HUVECs) associated with topo-graphic cues. Here, we showed that poly (dimethyl siloxane) (PDMS) substrate of 10 μm width and 3 μm depth parallel microgrooves on the surface could significantly upregulate the expression of anti-inflammatory microRNAs, miR-146a and miR-181b. In addition, the results also showed that TRAF6 and importin-α3, target of miR-146a and miR-181b, respectively, were both down-regulated (P < 0.05 and P < 0.001, respectively). The expression levels of the inflammation related proteins were all significantly decreased, including VCAM-1 (P < 0.05), ICAM-1 (P < 0.001), E-selectin (P < 0.001), and MCP-1 (P < 0.05). The adhesion of the mononuclear cell line, THP-1, was significantly decreased (P < 0.05). The results revealed that morphology modified HUVEC can modulate miR-146a and miR-181b and their downstream biological functions such as decreasing inflammation, suggesting that surface microtopology may affect vascular inflammation in the setting of cardiovascular disease. These interesting findings will facilitate the optimal design of microstructured materials in tissue engineering.

Identification of peptides derived from the C-terminal domain of fibulin-7 active for endothelial cell adhesion and tube formation disruption.

Despite the research done on pathological angiogenesis, there is still a need for the development of new therapies against angiogenesis-related diseases. Fibulin-7 (Fbln7) is a member of the extracellular matrix fibulin protein family. The Fbln7 C-terminal fragment, Fbln7-C, binds to endothelial cells and inhibits their tube formation in culture. In this study, we screened 12 synthetic peptides, covering the fibulin-globular domain of Fbln7-C, to identify active sites for endothelial cell adhesion and in vitro antiangiogenic activity. Three peptides, fc10, fc11, and fc12, promoted Human Umbilical Vein Endothelial Cells (HUVECs) adhesion, and the morphology of HUVECs on fc10 was similar to that on Fbln7-C. EDTA and the anti-integrin β1 function-blocking antibody inhibited HUVECs adhesion to both fc10 and fc12, and heparin inhibited HUVECs adhesion to both fc11 and fc12. fc10 and fc11 inhibited HUVECs tube formation. Our results suggest that three peptides from Fbln7-C are biologically active for endothelial cell adhesion and disrupt the tube formation, suggesting a potential therapeutic use of these peptides for angiogenesis-related diseases. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 184-195, 2016.

Cell Morphology Modified by Biomaterial Induces miR-21 Expression and Apoptosis

Biochemical factors can play an important role in regulating gene expression in human umbilical vein endothelial cells (HUVECs), yet the role of biophysical factors during this process is unknown. Here, we show that physical cues, in the form of parallel microgrooves on the surface of cell adhesive substrates, can change the morphology of HUVECs as well as specific microRNA expression. Cells cultured on microgrooved poly (dimethyl siloxane) (PDMS) surface exhibited a more elongated morphology relative to those cultured on flat surfaces, and favored outgrowth along the axis of groove alignment. The level of microRNAs in the cell was screened by miRNA microchip and verified by qRT-PCR. The result showed that around 26 microRNAs have been modified significantly, among which miR-21 level was dramatically elevated. Western-blotting analysis demonstrated that PTEN, a target of miR- 21, was up-regulated in HUVECs with elongated morphology. Cell apoptosis level was significantly decreased, with was associated with the increasing of miR-21 level. These results suggested that biophysical factors can directly modify HUVECs morphology, thus induce miR-21 expression in HUVECs and its downstream biological functions such as decreasing apoptosis. This study provided evidence that surface microtopology should also be considered in designing biomaterials in tissue engineering application.

The inhibitory effect of simvastatin and aspirin on histamine responsiveness in human vascular endothelial cells

Statins and aspirin deliver well-established cardiovascular benefits resulting in their increased use as combined polypills to decrease risk of stroke and heart disease. However, the direct endothelial effect of combined statin/aspirin cotreatment remains unclear. Histamine is an inflammatory mediator that increases vascular permeability, and so we examined the effect of treating human umbilical vein endothelial cells (HUVECs) for 24 h with 1 μM simvastatin and 100 μM aspirin on histamine responsiveness. Subsequent histamine (1 μM) challenge increased intracellular calcium (Ca(2+)i) concentration, an effect that was significantly inhibited by combined simvastatin/aspirin pretreatment but not when then the compounds were given separately, even at 10-fold higher concentrations. In contrast, the Ca(2+)i mobilization response to ATP challenge (10 μM) was not inhibited by combined simvastatin/aspirin pretreatment. The H1 receptor antagonist pyrilamine significantly inhibited both histamine-induced Ca(2+)i mobilization and extracellular signal-regulated kinase (ERK) activation, whereas ranitidine (H2 receptor antagonist) was without effect. However, combined simvastatin/aspirin pretreatment failed to decrease H1 receptor protein expression ruling out receptor downregulation as the mechanism of action. Histamine-induced ERK activation was also inhibited by atorvastatin pretreatment, while simvastatin further inhibited histamine-induced vascular endothelial cadherin phosphorylation as well as altered HUVEC morphology and inhibited actin polymerization. Therefore, in addition to the known therapeutic benefits of statins and aspirin, here we provide initial cellular evidence that combined statin/aspirin treatment inhibits histamine responsiveness in HUVECs.