Mangiferin alleviates diabetic pulmonary fibrosis in mice via inhibiting endothelial-mesenchymal transition through AMPK/FoxO3/SIRT3 axis

Diabetes mellitus results in numerous complications. Diabetic pulmonary fibrosis (DPF), a late pulmonary complication of diabetes, has not attracted as much attention as diabetic nephropathy and cardiomyopathy. Mangiferin (MF) is a natural small molecular compound that exhibits a variety of pharmacological effects including anti-inflammatory, anti-cancer, anti-diabetes, and anti-fibrosis effects. In this study, we investigated whether long-term diabetes shock induces DPF, and explored whether MF had a protective effect against DPF. We first examined the lung tissues and sections of 20 diabetic patients obtained from discarded lung surgical resection specimens and found that pulmonary fibrosis mainly accumulated around the pulmonary vessels, accompanied by significantly enhanced endothelial-mesenchymal transition (EndMT). We established a mouse model of DPF by STZ injections. Ten days after the final STZ injection, the mice were administered MF (20, 60 mg/kg, i.g.) every 3 days for 4 weeks, and kept feeding until 16 weeks and euthanized. We showed that pulmonary fibrotic lesions were developed in the diabetic mice, which began around the pulmonary vessels, while MF administration did not affect long-term blood glucose levels, but dose-dependently alleviated diabetes-induced pulmonary fibrosis. In human umbilical vein endothelial cells (HUVECs), exposure to high glucose (33.3 mM) induced EndMT, which was dose-dependently inhibited by treatment with MF (10, 50 μM). Furthermore, MF treatment promoted SIRT3 expression in high glucose-exposed HUVECs by directly binding to AMPK to enhance the activity of FoxO3, which finally reversed diabetes-induced EndMT. We conclude that MF attenuates DPF by inhibiting EndMT through the AMPK/FoxO3/SIRT3 axis. MF could be a potential candidate for the early prevention and treatment of DPF.

Polydopamine-Mediated Metal-Organic Frameworks Modification for Improved Biocompatibility

Engineered nanomaterials are promising in biomedical application. However, insufficient understanding of their biocompatibility at the cellular and organic levels prevents their widely biomedical applications. Metal-organic frameworks (MOFs) have attracted increasing attention in recent years. In this work, zeolitic imidazolate framework-8 (ZIF-8) and polydopamine (PDA)-modified ZIF-8 are chosen as model nanomaterials due to its emergent role in nanomedicine. In vitro, the results demonstrate that the PDA coating greatly alleviates the cytotoxicity of ZIF-8 to RAW264.7, LO2, and HST6, which represent three different cell types in liver organs. Mechanistically, ZIF-8 entering into the cells can greatly induce the reactive oxygen species generation, which subsequently induces cell cycle delay and autophagy, ultimately leads to enhanced cytotoxicity. Further, human umbilical vein endothelial cells model and zebrafish embryos assay also confirm that PDA can compromise the ZIF-8 toxicity significantly. This study reveals that PDA-coated MOFs nanomaterials show great potential in nano-based drug delivery systems .

Dapagliflozin alleviates high glucose-induced injury of endothelial cells via inducing autophagy

Hyperglycaemia is a key factor in the progression of diabetes complications. Dapagliflozin (DAPA), a new type of hypoglycaemic agent, has been shown to play an important role in anti-apoptotic, anti-inflammatory and antioxidant activities. Previous studies have demonstrated an endothelial protective effect of DAPA, but the underlying mechanism was still unclear. Autophagy is a homeostatic cellular mechanism that circulates unfolded proteins and damaged organelles through lysosomal dependent degradation. In this study, we aimed to investigate whether DAPA plays a protective role against high glucose (HG)-induced endothelial injury through regulating autophagy. The results showed that DAPA treatment resulted in increased cell viability. Additionally, DAPA treatment decreased interleukin (IL)-1β, IL-6, and tumour necrosis factor-α levels in endothelial cells subjected to HG conditions. We observed that HG inhibited autophagy, and DAPA increased the autophagy level by inhibiting the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signalling pathway. Chloroquine reversed all of these beneficial effects as an autophagy inhibitor. In summary, the endothelial protective effect of DAPA in HG can be attributed in part to its role in activating of autophagy via the AKT/mTOR signalling pathway. Therefore, suggesting that the activation of autophagy by DAPA may be a novel target for the treatment of HG-induced endothelial cell injury.

Piper sarmentosum Roxb. Inhibits Angiotensin-Converting Enzyme Activity in Phorbol 12-Myristate-13-Acetate-Induced Endothelial Cells

Angiotensin-converting enzyme (ACE) plays a crucial role in the pathogenesis of hypertension. Piper sarmentosum Roxb., an herb known for its antihypertensive effect, lacks a comprehensive understanding of the mechanism underlying its antihypertensive action. This study aimed to elucidate the antihypertensive mechanism of aqueous extract of P. sarmentosum leaves (AEPS) via its modulation of the ACE pathway in phorbol 12-myristate-13-acetate (PMA)-induced human umbilical vein endothelial cells (HUVECs). HUVECs were divided into five groups: control, treatment with 200 µg/mL AEPS, induction 200 nM PMA, concomitant treatment with 200 nM PMA and 200 µg/mL AEPS, and treatment with 200 nM PMA and 0.06 μM captopril. Subsequently, ACE mRNA expression, protein level and activity, angiotensin II (Ang II) levels, and angiotensin II type 1 receptor (AT1R) and angiotensin II type 2 receptor (AT2R) mRNA expression in HUVECs were determined. AEPS successfully inhibited ACE mRNA expression, protein and activity, and angiotensin II levels in PMA-induced HUVECs. Additionally, AT1R expression was downregulated, whereas AT2R expression was upregulated. In conclusion, AEPS reduces the levels of ACE mRNA, protein and activity, Ang II, and AT1R expression in PMA-induced HUVECs. Thus, AEPS has the potential to be developed as an ACE inhibitor in the future.

Hydroxysafflor Yellow A Inhibits Pyroptosis and Protecting HUVECs from OGD/R via NLRP3/Caspase-1/GSDMD Pathway

OBJECTIVE

To observe the protective effect and mechanism of hydroxyl safflower yellow A (HSYA) from myocardial ischemia-reperfusion injury on human umbilical vein endothelial cells (HUVECs).

METHODS

HUVECs were treated with oxygen-glucose deprivation reperfusion (OGD/R) to simulate the ischemia reperfusion model, and cell counting kit-8 was used to detect the protective effect of different concentrations (1.25-160 µ mol/L) of HSYA on HUVECs after OGD/R. HSYA 80 µ mol/L was used for follow-up experiments. The contents of inflammatory cytokines interleukin (IL)-18, IL-1 β, monocyte chemotactic protein 1 (MCP-1), tumor necrosis factor α (TNF-α) and IL-6 before and after administration were measured by enzyme-linked immunosorbent assay. The protein expressions of toll-like receptor, NOD-like receptor containing pyrin domain 3 (NLRP3), gasdermin D (GSDMD) and GSDMD-N-terminal domain (GSDMD-N) before and after administration were detected by Western blot. NLRP3 inflammasome inhibitor cytokine release inhibitory drug 3 sodium salt (CRID3 sodium salt, also known as MCC950) and agonist were added, and the changes of NLRP3, cysteine-aspartic acid protease 1 (Caspase-1), GSDMD and GSDMD-N protein expressions were detected by Western blot.

RESULTS

HSYA inhibited OGD/R-induced inflammation and significantly decreased the contents of inflammatory cytokines IL-18, IL-1 β, MCP-1, TNF-α and IL-6 (P<0.01 or P<0.05). At the same time, by inhibiting NLRP3/Caspase-1/GSDMD pathway, HSYA can reduce the occurrence of pyroptosis after OGD/R and reduce the expression of NLRP3, Caspase-1, GSDMD and GSDMD-N proteins (P<0.01).

CONCLUSIONS

The protective effect of HSYA on HUVECs after OGD/R is related to down-regulating the expression of NLRP3 inflammasome and inhibiting pyroptosis.

Apoptotic Extracellular Vesicles Derived from Human Umbilical Vein Endothelial Cells Promote Skin Repair by Enhancing Angiogenesis: From Death to Regeneration

Purpose

The promotion of angiogenesis is an effective strategy for skin wound repair. While the transplantation of endothelial cells has shown promise in vascularization, the underlying mechanism remains unclear. Recent studies have suggested that transplanted cells undergo apoptosis in a short period and release apoptotic extracellular vesicles (ApoEVs) that may have therapeutic potential.

Methods

In this study, we isolated ApoEVs from human umbilical vein endothelial cells (HUVECs) and characterized their properties. In vitro, we assessed the effects of ApoEVs on the proliferation, migration, and differentiation of endothelial cells and fibroblasts. In vivo, we investigated the therapeutic role of ApoEVs-AT in full-thickness skin wounds, evaluating wound closure rate, re-epithelialization, granulation tissue formation, vascularization, scar area, and collagen 3(Col3)/collagen 1(Col 1) ratio.

Results

ApoEVs derived from HUVECs displayed typical characteristics. In vitro, ApoEVs significantly enhanced the proliferation, migration, tube formation, and expression of angiogenic-related genes in endothelial cells and slightly promoted the proliferation and migration of fibroblasts. In vivo, ApoEVs improved the wound closure rate, re-epithelialization, the formation of granulation tissue, and vascularization. Besides, ApoEVs reduced scar formation, accompanied by an increase in the Col 3/ Col 1 ratio.

Conclusion

Given their abundant source and effectiveness, this study provided a novel approach for angiogenesis in tissue regeneration and deepened the understanding of from death to regeneration.

Ang1/Tie2/VE-Cadherin Signaling Regulates DPSCs in Vascular Maturation

Adding dental pulp stem cells (DPSCs) to vascular endothelial cell-formed vessel-like structures can increase the longevity of these vessel networks. DPSCs display pericyte-like cell functions and closely assemble endothelial cells (ECs). However, the mechanisms of DPSC-derived pericyte-like cells in stabilizing the vessel networks are not fully understood. In this study, we investigated the functions of E-DPSCs, which were DPSCs isolated from the direct coculture of human umbilical vein endothelial cells (HUVECs) and DPSCs, and T-DPSCs, which were DPSCs treated by transforming growth factor beta 1 (TGF-β1), in stabilizing blood vessels in vitro and in vivo. A 3-dimensional coculture spheroid sprouting assay was conducted to compare the functions of E-DPSCs and T-DPSCs in vitro. Dental pulp angiogenesis in the severe combined immunodeficiency (SCID) mouse model was used to explore the roles of E-DPSCs and T-DPSCs in vascularization in vivo. The results demonstrated that both E-DPSCs and T-DPSCs possess smooth muscle cell-like cell properties, exhibiting higher expression of the mural cell-specific markers and the suppression of HUVEC sprouting. E-DPSCs and T-DPSCs inhibited HUVEC sprouting by activating TEK tyrosine kinase (Tie2) signaling, upregulating vascular endothelial (VE)-cadherin, and downregulating vascular endothelial growth factor receptor 2 (VEGFR2). In vivo study revealed more perfused and total blood vessels in the HUVEC + E-DPSC group, HUVEC + T-DPSC group, angiopoietin 1 (Ang1) pretreated group, and vascular endothelial protein tyrosine phosphatase (VE-PTP) inhibitor pretreated group, compared to HUVEC + DPSC group. In conclusion, these data indicated that E-DPSCs and T-DPSCs could stabilize the newly formed blood vessels and accelerate their perfusion. The critical regulating pathways are Ang1/Tie2/VE-cadherin and VEGF/VEGFR2 signaling.

Relationship of human cytomegalovirus-infected endothelial cells and circulating leukocytes in the pathogenesis of disseminated human cytomegalovirus infection: A narrative review

Among the leucocyte subpopulations circulating in peripheral blood of immune-compromised patients with disseminated Human cytomegalovirus (HCMV) infection, polymorphonuclear leuckocytes (PMNL) and M/M may carry infectious virus. While only in PMNL early HCMV replicative events do occur, monocytes are susceptible to complete virus replication when they enter human organs, where as macrophages become a site of active complete virus replication. In vivo leucocytes and endothelial cells interact continuously, as suggested by several in vitro experimental findings showing the bidirectional HCMV transmission from leucocytes to and from endothelial cells with the critical aid of adhesion molecules. Recently, the neutralising antibody response in sera from subjects with primary HCMV infection was reported to be much higher and earlier than in human embryonic lung fibroblasts (HELF) cells when measured in endothelial cells and epithelial cells, where virus entry is mediated mostly by the pentamer complex gH/gL/pUL128/pUL130/pUL131, whereas it was much lower and delayed when determined in HELF, where virus entry is mediated mostly by the trimer complex gH/gL/gO. Thus, these results suggested that products of UL128L were the molecules primary responsible for the differential neutralising antibody response. This conclusion was confirmed by a series of polyclonal and monoclonal antibodies directed to the components of pUL128L. Very recently, based on two sets of experiments including inhibition and immunoblotting assays, the pentamer complex/trimer complex ratio has been finally identified as the main factor of the neutralising antibody response. This ratio may change with the virus suspension producer and target cell system as well as number of cell culture passages.

Qiqilian ameliorates vascular endothelial dysfunction by inhibiting NLRP3-ASC inflammasome activation in vivo and in vitro

CONTEXT

Previous studies have highlighted significant therapeutic effects of Qiqilian (QQL) capsule on hypertension in spontaneously hypertensive rats (SHRs); however, its underlying molecular mechanism remains unclear.

OBEJECTIVE

We investigated the potential mechanism by which QQL improves hypertension-induced vascular endothelial dysfunction (VED).

MATERIALS AND METHODS

In vivo, SHRs were divided into four groups (20 per group) and were administered gradient doses of QQL (0, 0.3, 0.6, and 1.2 g/kg) for 8 weeks, while Wistar Kyoto rats were used as normal control. The vascular injury extent, IL-1β and IL-18 levels, NLRP3, ASC and caspase-1 contents were examined. In vitro, the effects of QQL-medicated serum on angiotensin II (AngII)-induced inflammatory and autophagy in human umbilical vein endothelial cells (HUVECs) were assessed.

RESULT

Compared with the SHR group, QQL significantly decreased thickness (125.50 to 105.45 μm) and collagen density (8.61 to 3.20%) of arterial vessels, and reduced serum IL-1β (96.25 to 46.13 pg/mL) and IL-18 (345.01 to 162.63 pg/mL) levels. The NLRP3 and ACS expression in arterial vessels were downregulated (0.21- and 0.16-fold, respectively) in the QQL-HD group compared with the SHR group. In vitro, QQL treatment restored NLRP3 and ASC expression, which was downregulated approximately 2-fold compared with that of AngII-induced HUVECs. Furthermore, QQL decreased LC3II and increased p62 contents (p < 0.05), indicating a reduction in autophagosome accumulation. These effects were inhibited by the autophagy agonist rapamycin and enhanced by the autophagy inhibitor chloroquine.

CONCLUSION

QQL effectively attenuated endothelial injury and inflammation by inhibiting AngII-induced excessive autophagy, which serves as a potential therapeutic strategy for hypertension.

Manufacturing and Functional Characterization of Bioengineered Liver Grafts for Extracorporeal Liver Assistance in Acute Liver Failure

Acute Liver Failure (ALF) is a life-threatening illness characterized by the rapid onset of abnormal liver biochemistries, coagulopathy, and the development of hepatic encephalopathy. Extracorporeal bioengineered liver (BEL) grafts could offer a bridge therapy to transplant or recovery. The present study describes the manufacture of clinical scale BELs created from decellularized porcine-derived liver extracellular matrix seeded entirely with human cells: human umbilical vein endothelial cells (HUVECs) and primary human liver cells (PHLCs). Decellularized scaffolds seeded entirely with human cells were shown to adhere to stringent sterility and safety guidelines and demonstrated increased functionality when compared to grafts seeded with primary porcine liver cells (PPLCs). BELs with PHLCs were able to clear more ammonia than PPLCs and demonstrated lower perfusion pressures during patency testing. Additionally, to determine the full therapeutic potential of BELs seeded with PHLCs, longer culture periods were assessed to address the logistical constraints associated with manufacturing and transporting a product to a patient. The fully humanized BELs were able to retain their function after cold storage simulating a product transport period. Therefore, this study demonstrates the manufacture of bioengineered liver grafts and their potential in the clinical setting as a treatment for ALF.

[Corrigendum] The tetraspanin CD151‑ARSA mutant inhibits angiogenesis via the YRSL sequence

Subsequently to the publication of the above paper, an interested reader drew to the authors' attention that, in Fig. 4A on p. 839, the 'CD151/24 h' and 'CD151‑ARSA/48 h' panels appeared to contain overlapping sections of data, such that they were potentially derived from the same original source, where these panels were intended to show the results from differently performed experiments. The authors have re‑examined their original data, and realize that the 'CD151‑ARSA/48 h' panel was inadvertently placed incorrectly in the figure. The revised version of Fig. 4, now containing the correct data for the 'CD151‑ARSA/48 h' experiment in Fig. 4A, is shown below. Note that this error did not adversely affect either the results or the overall conclusions reported in this study. All the authors agree with the publication of this corrigendum, and are grateful to the Editor of Molecular Medicine Reports for allowing them the opportunity to publish this. They also wish to apologize to the readership of the Journal for any inconvenience caused. [Molecular Medicine Reports 7: 836‑842, 2013; DOI: 10.3892/mmr.2012.1250].

[Matrine inhibits inflammatory response induced by TNF-α in human umbilical vein endothelial cells through miR-25-3p-mediated Klf4 pathway]

This study aimed to analyze the effect of matrine on tumor necrosis factor-α(TNF-α)-induced inflammatory response in human umbilical vein endothelial cells(HUVECs) and explore whether the underlying mechanism was related to the miR-25-3p-mediated Krüppel-like factor 4(Klf4) pathway. The HUVEC cell inflammation model was induced by TNF-α stimulation. After 24 or 48 hours of incubation with different concentrations of matrine(0.625, 1.25, and 2.5 mmol·L~(-1)), CCK-8 assay was used to detect cell proliferation. After treatment with 2.5 mmol·L~(-1) matrine for 48 h, the expression of TNF-α, interleukin-6(IL-6), interleukin-1β(IL-1β), and Klf4 mRNA and miR-25-3p was detected by real-time fluorescence-based quantitative PCR, and the protein expression of TNF-α, IL-6, IL-1β, and Klf4 was detected by Western blot. The anti-miR-25-3p was transfected into HUVECs, and the effect of anti-miR-25-3p on TNF-α-induced cell proliferation and inflammatory factors was detected by the above method. The cells were further transfected with miR-25-3p and incubated with matrine to detect the changes in proliferation and expression of related inflammatory factors, miR-25-3p, and Klf4. The targeting relationship between miR-25-3p and Klf4 was verified by bioinformatics analysis and dual luciferase reporter gene assay. The results displayed that matrine could inhibit TNF-α-induced HUVEC proliferation, decrease the mRNA and protein expression of TNF-α, IL-6, and IL-1β, increase the mRNA and protein expression of Klf4, and reduce the expression of miR-25-3p. Bioinformatics analysis showed that there were specific complementary binding sites between miR-25-3p and Klf4 sequences. Dual luciferase reporter gene assay confirmed that miR-25-3p negatively regulated Klf4 expression in HUVECs by targeting. The inhibition of miR-25-3p expression can reduce TNF-α-induced cell proliferation and mRNA and protein expression of TNF-α, IL-6, and IL-1β. MiR-25-3p overexpression could reverse the effect of matrine on TNF-α-induced cell proliferation and the mRNA and protein expression of TNF-α, IL-6, IL-1β, and Klf4. This study shows that matrine inhibits the inflammatory response induced by TNF-α in HUVECs through miR-25-3p-mediated Klf4 pathway.

Observing Extracellular Vesicles Originating from Endothelial Cells in Vivo Demonstrates Improved Astrocyte Function Following Ischemic Stroke via Aggregation-Induced Emission Luminogens

Extracellular vesicles (EVs) obtained from endothelial cells (ECs) have significant therapeutic potential in the clinical management of individuals with ischemic stroke (IS) because they effectively treat ischemic stroke in animal models. However, because molecular probes with both high labeling efficiency and tracer stability are lacking, monitoring the actions of EC-EVs in the brain remains difficult. The specific intracellular targets in the brain that EC-EVs act on to produce their protective effects are still unknown, greatly impeding their use in clinical settings. For this research, we created a probe that possessed aggregation-induced emission (AIE) traits (namely, TTCP), enabling the effective labeling of EC-EVs while preserving their physiological properties. In vitro, TTCP simultaneously had a higher EC-EV labeling efficiency and better tracer stability than the commercial EV tags PKH-67 and DiI. In vivo, TTCP precisely tracked the actions of EC-EVs in a mouse IS model without influencing their protective effects. Furthermore, through the utilization of TTCP, it was determined that astrocytes were the specific cells affected by EC-EVs and that EC-EVs exhibited a safeguarding impact on astrocytes following cerebral ischemia-reperfusion (I/R) injury. These protective effects encompassed the reduction of the inflammatory reaction and apoptosis as well as the enhancement of cell proliferation. Further analysis showed that miRNA-155-5p carried by EC-EVs is responsible for these protective effects via regulation of the c-Fos/AP-1 pathway; this information provided a strategy for IS therapy. In conclusion, TTCP has a high EC-EV labeling efficiency and favorable in vivo tracer stability during IS therapy. Moreover, EC-EVs are absorbed by astrocytes during cerebral I/R injury and promote the restoration of neurological function through the regulation of the c-Fos/AP-1 signaling pathway.

LncRNA HCG27 Promotes Glucose Uptake Ability of HUVECs by MiR-378a-3p/MAPK1 Pathway

OBJECTIVE

Gestational diabetes mellitus (GDM) is the most common metabolic disorder during pregnancy. LncRNA HLA complex group 27 (HCG27) plays a crucial role in various metabolic diseases. However, the relationship between lncRNA HCG27 and GDM is not clear. This study aimed to verify a competing endogenous RNA (ceRNA) interaction regulation axis of miR-378a-3p/mitogen-activated protein kinase 1 (MAPK1) regulated by HCG27 in GDM.

METHODS

LncRNA HCG27 and miR-378a-3p were detected by RT-qPCR. The expression of MAPK1 in umbilical vein endothelial cells (HUVECs) was detected by RT-qPCR and that in the placenta by Western blotting. To explore the relationship among lncRNA HCG27, miR-378a-3p, MAPK1 and the glucose uptake ability of HUVECs, vector HCG27, si-HCG27, miR-378a-3p mimic and inhibitor were transfected to achieve overexpression and inhibition of HCG27 or miR-378a-3p. The interaction between miR-378a-3p and lncRNA HCG27 or MAPK1 was confirmed by the dual-luciferase reporter assay. Besides, glucose consumption by HUVECs was detected by the glucose assay kit.

RESULTS

HCG27 expression was significantly decreased in both the placenta and primary umbilical vein endothelial cells, while the expression of miR-378a-3p was significantly increased in GDM tissues, and the expression of MAPK1 was decreased in GDM tissues. This ceRNA interaction regulation axis was proved to affect the glucose uptake function of HUVECs. The transfection of si-HCG27 could significantly reduce the expression of the MAPK1 protein. If the MAPK1 overexpression plasmid was transfected simultaneously with si-HCG27 transfection, the reduced glucose uptake in HUVECs resulting from the decrease in lncRNA HCG27 was reversed. MiR-378a-3p mimic can significantly reduce the mRNA expression of MAPK1 in HUVECs, whereas miR-378a-3p inhibitor can significantly increase the mRNA expression of MAPK1. The inhibition of miR-378a-3p could restore the decreased glucose uptake of HUVECs treated with si-HCG27. Besides, overexpression of lncRNA HCG27 could restore the glucose uptake ability of the palmitic acid-induced insulin resistance model of HUVECs to normal.

CONCLUSION

LncRNA HCG27 promotes glucose uptake of HUVECs by miR-378a-3p/MAPK1 pathway, which may provide potential therapeutic targets for GDM. Besides, the fetal umbilical cord blood and umbilical vein endothelial cells collected from pregnant women with GDM after delivery could be used to detect the presence of adverse molecular markers of metabolic memory, so as to provide guidance for predicting the risk of cardiovascular diseases and health screening of offspring.

Downregulation of VEGFR2 signaling by cedrol abrogates VEGF‑driven angiogenesis and proliferation of glioblastoma cells through AKT/P70S6K and MAPK/ERK1/2 pathways

Cedrol is a sesquiterpene alcohol isolated from Cedrus atlantica, which has been traditionally used in aromatherapy and has anticancer, antibacterial and antihyperalgesic effects. One characteristic of glioblastoma (GB) is the overexpression of vascular endothelial growth factor (VEGF), which induces a high degree of angiogenesis. Although previous studies have reported that cedrol inhibits GB growth by inducing DNA damage, cell cycle arrest and apoptosis, its role in angiogenesis remains unclear. The aim of the present study was to investigate the effects of cedrol on VEGF-induced angiogenesis of human umbilical vein endothelial cells (HUVECs). HUVECs were treated with 0-112 µM cedrol and 20 ng/ml VEGF for 0-24 h, and then anti-angiogenic activation of cedrol was determined by MTT assay, wound healing assay, Boyden chamber assay, tube formation assay, semi-quantitative reverse transcription-PCR and western blotting. These results demonstrated that cedrol treatment inhibited VEGF-induced cell proliferation, migration and invasion in HUVECs. Furthermore, cedrol prevented VEGF and DBTRG-05MG GB cells from inducing capillary-like tube formation in HUVECs and decreased the number of branch points formed. Moreover, cedrol downregulated the phosphorylation of VEGF receptor 2 (VEGFR2) and the expression levels of its downstream mediators AKT, ERK, VCAM-1, ICAM-1 and MMP-9 in HUVECs and DBTRG-05MG cells. Taken together, these results demonstrated that cedrol exerts anti-angiogenic effects by blocking VEGFR2 signaling, and thus could be developed into health products or therapeutic agents for the prevention or treatment of cancer and angiogenesis-related diseases in the future.

Anti-Cancer Prodrug Cyclophosphamide Exerts Thrombogenic Effects on Human Venous Endothelial Cells Independent of CYP450 Activation-Relevance to Thrombosis

Cancer patients are at a very high risk of serious thrombotic events, often fatal. The causes discussed include the detachment of thrombogenic particles from tumor cells or the adverse effects of chemotherapeutic agents. Cytostatic agents can either act directly on their targets or, in the case of a prodrug approach, require metabolization for their action. Cyclophosphamide (CPA) is a widely used cytostatic drug that requires prodrug activation by cytochrome P450 enzymes (CYP) in the liver. We hypothesize that CPA could induce thrombosis in one of the following ways: (1) damage to endothelial cells (EC) after intra-endothelial metabolization; or (2) direct damage to EC without prior metabolization. In order to investigate this hypothesis, endothelial cells (HUVEC) were treated with CPA in clinically relevant concentrations for up to 8 days. HUVECs were chosen as a model representing the first place of action after intravenous CPA administration. No expression of CYP2B6, CYP3A4, CYP2C9 and CYP2C19 was found in HUVEC, but a weak expression of CYP2C18 was observed. CPA treatment of HUVEC induced DNA damage and a reduced formation of an EC monolayer and caused an increased release of prostacyclin (PGI2) and thromboxane (TXA) associated with a shift of the PGI2/TXA balance to a prothrombotic state. In an in vivo scenario, such processes would promote the risk of thrombus formation.

An epigenetic clock for gestational age based on human umbilical vein endothelial cells from a diverse population of newborns

Background

Epigenetic clocks are emerging as a useful tool in many areas of research. Many epigenetic clocks have been developed for adults; however, there are fewer clocks focused on newborns and most are trained using blood from European ancestry populations. In this study, we built an epigenetic clock based on primary human umbilical vein endothelial cells from a racially and ethnically diverse population.

Results

Using human umbilical vein endothelial cell [HUVEC]-derived DNA, we calculated epigenetic gestational age using 83 CpG sites selected through elastic net regression. In this study with newborns from different racial/ethnic identities, epigenetic gestational age and clinical gestational age were more highly correlated (r = 0.85), than epigenetic clocks built from adult and other pediatric populations. The correlation was also higher than clocks based on blood samples from newborns with European ancestry. We also found that birth weight was positively associated with epigenetic gestational age acceleration (EGAA), while NICU admission was associated with lower EGAA. Newborns self-identified as Hispanic or non-Hispanic Black had lower EGAA than self-identified as non-Hispanic White.

Conclusions

Epigenetic gestational age can be used to estimate clinical gestational age and may help index neonatal development. Caution should be exercised when using epigenetic clocks built from adults with children, especially newborns. We highlight the importance of cell type-specific epigenetic clocks and general pan tissue epigenetic clocks derived from a large racially and ethnically diverse population.

Human IL-32θA94V mutant attenuates monocyte-endothelial adhesion by suppressing the expression of ICAM-1 and VCAM-1 via binding to cell surface receptor integrin αVβ3 and αVβ6 in TNF-α-stimulated HUVECs

Interleukin-32 (IL-32), first reported in 2005, and its isoforms have been the subject of numerous studies investigating their functions in virus infection, cancer, and inflammation. IL-32θ, one of the IL-32 isoforms, has been shown to modulate cancer development and inflammatory responses. A recent study identified an IL-32θ mutant with a cytosine to thymine replacement at position 281 in breast cancer tissues. It means that alanine was also replaced to valine at position 94 in amino acid sequence (A94V). In this study, we investigated the cell surface receptors of IL-32θA94V and evaluated their effect on human umbilical vein endothelial cells (HUVECs). Recombinant human IL-32θA94V was expressed, isolated, and purified using Ni-NTA and IL-32 mAb (KU32-52)-coupled agarose columns. We observed that IL-32θA94V could bind to the integrins αVβ3 and αVβ6, suggesting that integrins act as cell surface receptors for IL-32θA94V. IL-32θA94V significantly attenuated monocyte-endothelial adhesion by inhibiting the expression of Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor (TNF)-α-stimulated HUVECs. IL-32θA94V also reduced the TNF-α-induced phosphorylation of protein kinase B (AKT) and c-jun N-terminal kinases (JNK) by inhibiting phosphorylation of focal adhesion kinase (FAK). Additionally, IL-32θA94V regulated the nuclear translocation of nuclear factor kappa B (NF-κB) and activator protein 1 (AP-1), which are involved in ICAM-1 and VCAM-1 expression. Monocyte-endothelial adhesion mediated by ICAM-1 and VCAM-1 is an important early step in atherosclerosis, which is a major cause of cardiovascular disease. Our findings suggest that IL-32θA94V binds to the cell surface receptors, integrins αVβ3 and αVβ6, and attenuates monocyte-endothelial adhesion by suppressing the expression of ICAM-1 and VCAM-1 in TNF-α-stimulated HUVECs. These results demonstrate that IL-32θA94V can act as an anti-inflammatory cytokine in a chronic inflammatory disease such as atherosclerosis.

The use of commercial fibrin glue in dermal replacement material reduces angiogenic and lymphangiogenic gene and protein expression in vitro

BACKGROUND

Commercial fibrin glue is increasingly finding its way into clinical practice in surgeries to seal anastomosis, and initiate hemostasis or tissue repair. Human biological glue is also being discussed as a possible cell carrier. To date, there are only a few studies addressing the effects of fibrin glue on the cell-molecular level. This study examines the effects of fibrin glue on angiogenesis and lymphangiogenesis, as well as adipose-derived stem cells (ASCs) with a focus on gene and protein expression in scaffolds regularly used for tissue engineering approaches.

METHODS

Collagen-based dermal regeneration matrices (DRM) were seeded with human umbilical vein endothelial cells (HUVEC), human dermal lymphatic endothelial cells (LECs), or adipose-derived stem cells (ASC) and fixed with or without fibrin glue according to the experimental group. Cultures were maintained for 1 and 7 days. Finally, angiogenic and lymphangiogenic gene and protein expression were measured with special regard to subtypes of vascular endothelial growth factor (VEGF) and corresponding receptors using Multiplex-qPCR and ELISA assays. In addition, the hypoxia-induced factor 1-alpha (HIF1a) mediated intracellular signaling pathways were included in assessments to analyze a hypoxic encapsulating effect of fibrin polymers.

RESULTS

All cell types reacted to fibrin glue application with an alteration of gene and protein expression. In particular, vascular endothelial growth factor A (VEGFA), vascular endothelial growth factor B (VEGFB), vascular endothelial growth factor C (VEGFC), vascular endothelial growth receptor 1 (VEGFR1/FLT1), vascular endothelial growth receptor 2 (VEGFR2/KDR), vascular endothelial growth receptor 3 (VEGFR3/FLT4) and Prospero Homeobox 1 (PROX1) were depressed significantly depending on fibrin glue. Especially short-term fibrin effect led to a continuous downregulation of respective gene and protein expression in HUVECs, LECs, and ASCs.

CONCLUSION

Our findings demonstrate the impact of fibrin glue application in dermal regeneration with special regard to angiogenesis and lymphangiogenesis. In particular, a short fibrin treatment of 24 hours led to a decrease in gene and protein levels of LECS, HUVECs, and ASCs. In contrast, the long-term application showed less effect on gene and protein expressions. Therefore, this work demonstrated the negative effects of fibrin-treated cells in tissue engineering approaches and could affect wound healing during dermal regeneration.

Endothelial KCa3.1 and KCa2.3 Mediate S1P (Sphingosine-1-Phosphate)-Dependent Vasodilation and Blood Pressure Homeostasis

BACKGROUND

S1P (sphingosine-1-phosphate) has been reported to possess vasodilatory properties, but the underlying pathways are largely unknown.

METHODS

Isolated mouse mesenteric artery and endothelial cell models were used to determine S1P-induced vasodilation, intracellular calcium, membrane potentials, and calcium-activated potassium channels (K_Ca2.3 and K_Ca3.1). Effect of deletion of endothelial S1PR1 (type 1 S1P receptor) on vasodilation and blood pressure was evaluated.

RESULTS

Mesenteric arteries subjected to acute S1P stimulation displayed a dose-dependent vasodilation response, which was attenuated by blocking endothelial K_Ca2.3 or K_Ca3.1 channels. In cultured human umbilical vein endothelial cells, S1P stimulated immediate membrane potential hyperpolarization following activation of K_Ca2.3/K_Ca3.1 with elevated cytosolic Ca²⁺. Further, chronic S1P stimulation enhanced expression of K_Ca2.3 and K_Ca3.1 in human umbilical vein endothelial cells in dose- and time-dependent manners, which was abolished by disrupting either S1PR1-Ca²⁺ signaling or downstream Ca²⁺-activated calcineurin/NFAT (nuclear factor of activated T-cells) signaling. By combination of bioinformatics-based binding site prediction and chromatin immunoprecipitation assay, we revealed in human umbilical vein endothelial cells that chronic activation of S1P/S1PR1 promoted NFATc2 nuclear translocation and binding to promoter regions of K_Ca2.3 and K_Ca3.1 genes thus to upregulate transcription of these channels. Deletion of endothelial S1PR1 reduced expression of K_Ca2.3 and K_Ca3.1 in mesenteric arteries and exacerbated hypertension in mice with angiotensin II infusion.

CONCLUSIONS

This study provides evidence for the mechanistic role of K_Ca2.3/K_Ca3.1-activated endothelium-dependent hyperpolarization in vasodilation and blood pressure homeostasis in response to S1P. This mechanistic demonstration would facilitate the development of new therapies for cardiovascular diseases associated with hypertension.

Transcription factor cellular promoter 2 is required for upstream binding protein 1 -mediated angiogenesis

OBJECTIVE

Angiogenesis is a key process of repairing tissue damage, and it is regulated by the delicate balance between anti-angiogenesis factors. In the present study, we investigate whether transcription factor cellular promoter 2 (TFCP2) is required for upstream binding protein 1 (UBP1)-mediated angiogenesis.

METHODS

Levels of UBP1 and TFCP2 in human umbilical vein endothelial cells (HUVECs) are detected by quantitative polymerase chain reaction (q-PCR) and Western blotting (WB). Effects of UBP1 on angiogenesis and migration are detected by tube-like network formation on matrigel assay and scratch assay. The interaction between UBP1 and TFCP2 is predicted and verified by STRING and Co-immunoprecipitation (Co-IP).

RESULTS

Firstly, the UBP1 expression level was up-regulated in the stimuli of vascular endothelial growth factor (VEGF) in HUVECs, and the knockdown of UBP1 inhibited angiogenesis and migration of HUVECs. Then, UBP1 interacted with TFCP2. Besides, the TFCP2 expression level was up-regulated in VEGF-stimulated HUVECs. Furthermore, knockdown of TFCP2 inhibited angiogenesis and migration in VEGF-stimulated HUVECs, and down-regulation of UBP1 enhanced the inhibition.

CONCLUSION

TFCP2 also plays a key role in UBP1 mediated angiogenesis of HUVECs stimulated by VEGF. These findings will provide a new theoretical basis for the treatment of angiogenic diseases.

Activating autophagy and ferroptosis of 3‑Chloropropane‑1,2‑diol induces injury of human umbilical vein endothelial cells via AMPK/mTOR/ULK1

3‑Chloropropane‑1,2‑diol (3‑MCPD) is an internationally recognized food pollutant. 3‑MCPD has reproductive, renal and neurotoxic properties. However, whether 3‑MCPD induces human umbilical vein endothelial cell (HUVEC) injury has not been previously reported. In the present study, HUVECs were treated using 2 µg/ml 3‑MCPD for 24 h at 37˚C. The effects of 3‑MCPD on HUVEC proliferation and cell cycle arrest, death and senescence were then assessed using Cell Counting Kit‑8 (CCK‑8), flow cytometry and β‑galactosidase staining, respectively. Whether 3‑MCPD induced ferroptosis was evaluated using JC‑1 and FerroOrange staining and transmission electron microscopy. A small interfering RNA targeting AMPK was used to assess whether 3‑MCPD promoted ferroptosis via AMPK signaling. The results demonstrated that 3‑MCPD inhibited HUVEC proliferation in a dose‑dependent manner and induced cell cycle arrest. Furthermore, 3‑MCPD promoted senescence in HUVECs with elevated DNA damage and cell death. The CCK‑8 results demonstrated that ferroptosis and autophagy inhibitors significantly reversed cell death caused by 3‑MCPD. Moreover, 3‑MCPD increased mitochondrial membrane potential, which indicated that 3‑MCPD contributed to mitochondrial dysfunction. 3‑MCPD also markedly increased intracellular Fe2+ levels and lipid peroxidation in HUVECs. The present study assessed the underlying mechanism by which 3‑MCPD activated autophagy and ferroptosis in HUVECs. The data demonstrated that 3‑MCPD significantly increased phosphorylation levels of AMPK and unc‑51 like autophagy activating kinase (ULK1) but significantly decreased phosphorylation of mTOR in HUVECs. Furthermore, silencing of AMPK significantly reversed the increase in autophagy, lipid peroxidation and Fe2+ induced by 3‑MCPD. In conclusion, 3‑MCPD demonstrated a significant damaging effect on HUVECs via induction of autophagy and ferroptosis; such effects may be mediated by AMPK/mTOR/ULK1 signaling. To the best of our knowledge, the present study was the first to demonstrate the mechanism of 3‑MCPD‑induced vascular endothelial cell injury and lays a molecular foundation for the prevention of 3‑MCPD‑related vascular diseases.

Fibrin-Enriched Cardiac Extracellular Matrix Hydrogel Promotes In Vitro Angiogenesis

Angiogenesis is essential for cardiac repair after myocardial infarction. Promoting angiogenesis has been demonstrated as an effective approach for myocardial infarction treatment. Several different strategies for inducing myocardial angiogenesis have been explored, including exogenous delivery of angiogenic genes, proteins, microRNAs, cells, and extracellular vesicles. Various types of injectable hydrogels have been investigated for cardiac tissue repair. One of the most promising injectable hydrogels in cardiac regeneration is a cardiac extracellular matrix hydrogel that is derived from decellularized porcine myocardium. It can be delivered minimally invasively via transendocardial delivery. The safety and efficacy of cardiac extracellular matrix hydrogels have been shown in small and large animal myocardial infarction models as well as clinical trials. The main mechanisms underlying the therapeutic benefits of cardiac extracellular matrix hydrogels have been elucidated and involved in the modulation of the immune response, downregulation of pathways related to heart failure progression and fibrosis, upregulation of genes important for cardiac muscle contraction, and enhancing cardiomyocyte differentiation and maturation from stem cells. However, no potent capillary network formation induced by cardiac extracellular matrix hydrogels has been reported. In this study, we tested the feasibility of incorporating a fibrin matrix into cardiac extracellular matrix hydrogels to improve the angiogenic properties of the hydrogel. Our in vitro results demonstrate that fibrin-enriched cardiac extracellular matrix hydrogels can induce robust endothelial cell tube formation from human umbilical vein endothelial cells and promote the sprouting of human mesenchymal stem cell spheroids. The obtained information from this study is very critical toward the future in vivo evaluation of fibrin-enriched cardiac extracellular matrix hydrogels in promoting myocardial angiogenesis.

NEDD4 attenuates oxidized low‑density lipoprotein‑induced inflammation and dysfunction in vascular endothelial cells via regulating APEX1 expression

Atherosclerosis chiefly results from inflammation as well as vascular endothelial cell dysfunction. Methylation levels of neuronally expressed developmentally downregulated 4 (NEDD4) were found to be fortified in atherosclerosis patients and NEDD4 deficiency enhanced vascular calcification. However, the exact function of NEDD4 in inflammation and vascular endothelial dysfunction remains to be elucidated. In the present study, CCK-8 assay was used to estimate cell viability. Reverse transcription-quantitative PCR was adopted to examine the expression of NEDD4, inflammation-associated enzymes and apurinic/apyrimidinic endodeoxyribonuclease 1 (APEX1). Western blotting was used to test NEDD4, endothelial nitric oxide synthase, inducible nitric oxide synthase and APEX1 protein levels. Cytotoxicity was detected by a lactate dehydrogenase (LDH) kit. Reactive oxygen species level was tested by a corresponding kit. Vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 contents were examined with ELISA. Cell adhesion assays evaluated the adhesion of endothelial cells. Co-immunoprecipitation assay was used to test the relationship between NEDD4 and APEX1. The data revealed that NEDD4 expression rapidly declined in oxidized low density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells (HUVECs). Following NEDD4 overexpression, the active damage, inflammatory release and endothelial cell dysfunction in ox-LDL-induced HUVECs were attenuated. After co-transfection of APEX1 interference plasmids and NEDD4 overexpression plasmids, cell damage, inflammatory release and endothelial cell dysfunction in ox-LDL-induced HUVECs were improved again. Taken together, NEDD4 attenuated ox-LDL-induced inflammation and endothelial dysfunction by regulating APEX1 expression.

Enhanced external counterpulsation improves dysfunction of forearm muscle caused by radial artery occlusion

Objective

This study aimed to investigate the therapeutic effect of enhanced external counterpulsation (EECP) on radial artery occlusion (RAO) through the oscillatory shear (OS) and pulsatile shear (PS) models of human umbilical vein endothelial cells (HUVECs) and RAO dog models.

Methods

We used high-throughput sequencing data GSE92506 in GEO database to conduct time-series analysis of functional molecules on OS intervened HUVECs, and then compared the different molecules and their functions between PS and OS. Additionally, we studied the effect of EECP on the radial artery hemodynamics in Labrador dogs through multi-channel physiological monitor. Finally, we studied the therapeutic effect of EECP on RAO at the histological level through Hematoxylin-Eosin staining, Masson staining, ATPase staining and immunofluorescence in nine Labrador dogs.

Results

With the extension of OS intervention, the cell cycle decreased, blood vessel endothelial cell proliferation and angiogenesis responses of HUVECs were down-regulated. By contrast, the inflammation and oxidative stress responses and the related pathways of anaerobic metabolism of HUVECs were up-regulated. Additionally, we found that compared with OS, PS can significantly up-regulate muscle synthesis, angiogenesis, and NO production related molecules. Meanwhile, PS can significantly down-regulate inflammation and oxidative stress related molecules. The invasive arterial pressure monitoring showed that 30Kpa EECP treatment could significantly increase the radial artery peak pressure (p = 0.030, 95%CI, 7.236-82.524). Masson staining showed that RAO significantly increased muscle interstitial fibrosis (p = 0.002, 95%CI, 0.748-2.128), and EECP treatment can reduce this change (p = 0.011, 95%CI, -1.676 to -0.296). ATPase staining showed that RAO significantly increased the area of type II muscle fibers (p = 0.004, 95%CI, 7.181-25.326), and EECP treatment could reduce this change (p = 0.001, 95%CI, -29.213 to -11.069). In addition, immunofluorescence showed that EECP increased angiogenesis in muscle tissue (p = 0.035, 95%CI, 0.024-0.528).

Conclusion

EECP improves interstitial fibrosis and hypoxia, and increases angiogenesis of muscle tissue around radial artery induced by RAO.

Asiaticoside Prevents Oxidative Stress and Apoptosis in Endothelial Cells by Activating ROS-dependent p53/Bcl-2/Caspase-3 Signaling Pathway

BACKGROUND

Asiaticoside (AC) is a triterpenoid saponin found in Centella asiatica (L.) urban extract that has a wide range of pharmacological properties. Our previous study demonstrated that AC could promote angiogenesis in diabetic wounds, but the specific mechanisms remain unknown.

OBJECTIVE

This study aimed to examine the effectiveness and mechanism of AC on human umbilical vein endothelial cells (HUVECs) exposed to tert-butyl hydroperoxide (t-BHP) toxicity.

METHODS

Senescence was confirmed using senescence-associated betagalactosidase (SA-β-gal) activity and expression of the cell cycle phase markers p16 and p21. The levels of SOD, NO, MDA, GSH-Px, and ROS were tested. Furthermore, several cell death-related genes and proteins (p53, Bax, Bcl-2 and Caspase-3) were assessed with RT-qPCR and Western blotting.

RESULTS

AC significantly reduced SA-β-gal activity, with both the suppression of cellcycle inhibitors p16 and p21. We also found that the induced oxidative stress and apoptosis caused by t-BHP treatment resulted in the decrease of antioxidant enzymes activities, the surge of ROS and MDA, the up-regulation of p53, Bax and caspase-3, and the decrease of SOD, NO, GSH-Px and Bcl-2. These biochemical changes were all reversed by treatment with varying doses of AC.

CONCLUSION

AC alleviates t-BHP-induced oxidative injury and apoptosis in HUVECs through the ROS-dependent p53/Bcl-2/Caspase-3 signaling pathway. It may be a potential antioxidant applied in metabolic disorders and pharmaceutical products.

Bioactive polyphenols separated from hemp seed shells ameliorate H2 O2 -induced oxidative stress injury in human umbilical vein endothelial cells

In the present study, we investigated the protection of hemp seed polyphenols on human umbilical vein endothelial cells (HUVEC) from H₂ O₂ -mediated oxidative stress injury. Fractions with different polarities were obtained by separating the hemp seed extract using HPD300 macroporous resin-packed column. The fraction, desorbed by 50% ethanol, is rich in polyphenol (789.51 ± 21.92 mg GAE/g) and has the highest antioxidant activity in vitro. HPLC-QTOF-MS/MS identified the main polyphenol components in hemp seed shells: 4 hydroxycinnamic acid amides and 15 lignanamides. The protective effects of hemp seed polyphenol against oxidative-stress injury in HUVEC cells were evaluated by cell viability, intracellular antioxidant parameters, and cell apoptosis assay. After HUVEC cells were precultured with 50 µg/ml hemp seed polyphenols, the cell viability increased significantly from 53.07 ± 2.46% (model group) to 80.65 ± 1.32% (p < 0.01). In addition, the pretreatment of HUVEC cells with polyphenol could substantially increase their intracellular superoxide dismutase activity and reduce their intracellular reactive oxygen species level, malondialdehyde content, and lactate dehydrogenase leakage index. These findings demonstrate the defensive potential of hemp seed polyphenol in reducing the incidence of cardiovascular disease. PRACTICAL APPLICATION: Hemp seed shell waste is produced while producing hemp seed kernel and has abundant phenolic compounds. This research showed that hemp seed polyphenol has potent antioxidant activity in vitro and protects HUVEC cells against H₂ O₂ -induced oxidative stress injury, suggesting that hemp seed polyphenol has the defensive potential to reduce the incidence of cardiovascular disease. These results indicated that polyphenol separated from hemp seed shells is valuable for further research and development, which will improve the utilization rate of hemp seed.

CCL2 promotes proliferation, migration and angiogenesis through the MAPK/ERK1/2/MMP9, PI3K/AKT, Wnt/β‑catenin signaling pathways in HUVECs

Severe bone trauma can lead to poor or delayed bone healing and nonunion. Bone regeneration is based on the interaction between osteogenesis and angiogenesis. Angiogenesis serves a unique role in the repair and remodeling of bone defects. Monocyte chemoattractant protein-1, also known as CC motif ligand 2 (CCL2), is a member of the CC motif chemokine family and was the first human chemokine to be revealed to be an effective chemokine of monocytes. However, its underlying mechanism in angiogenesis of bone defect repair remains to be elucidated. Therefore, the present study investigated the detailed mechanism by which CCL2 promoted angiogenesis in bone defects based on cell and animal model experiments. In the present study, CCL2 promoted proliferation, migration and tube formation in human umbilical vein endothelial cells (HUVECs) in a concentration-dependent manner. Western blot analysis revealed that treatment of HUVECs with CCL2 upregulated the protein expression levels of rho-associated coiled-coil-containing protein kinase (Rock)1, Rock2, N-cadherin, c-Myc and VEGFR2. Furthermore, CCL2 promoted the expression of MAPK/ERK1/2/MMP9, PI3K/AKT and Wnt/β-catenin signaling pathway-related proteins, which also demonstrated that CCL2 promoted these functions in HUVECs. Immunohistochemical staining of Sprague Dawley rat femurs following bone defects revealed that VEGF expression was positive in the newly formed bone area in each group, while the expression area of VEGF in the CCL2 addition group was markedly increased. Therefore, CCL2 is a potential therapeutic approach for bone defect repair and reconstruction through the mechanism of angiogenesis-osteogenesis coupling.

Tissue Derivation and Biological Sex Uniquely Mediate Endothelial Cell Protein Expression, Redox Status, and Nitric Oxide Synthesis

Human endothelial cells are routinely utilized in cardiovascular research to provide a translational foundation for understanding how the vascular endothelium functions in vivo. However, little attention has been given to whether there are sex specific responses in vitro. Similarly, it is unclear whether endothelial cells derived from distinct tissues behave in a homogenous manner. Herein, we demonstrate that marked sex differences exist within, and between, commonly utilized human primary endothelial cells from healthy donors, with respect to redox status, nitric oxide synthesis, and associated proteins that can mediate their expression. Further, we demonstrate that endothelial cells respond uniquely to inflammatory insult in a sex- and tissue origin-dependent manner. Our findings suggest sex and tissue derivation may need to be considered when studying endothelial cells in vitro as cells derived from distinct tissue and sexes may not behave interchangeably.

HIF1A Knockout by Biallelic and Selection-Free CRISPR Gene Editing in Human Primary Endothelial Cells with Ribonucleoprotein Complexes

Primary endothelial cells (ECs), especially human umbilical vein endothelial cells (HUVECs), are broadly used in vascular biology. Gene editing of primary endothelial cells is known to be challenging, due to the low DNA transfection efficiency and the limited proliferation capacity of ECs. We report the establishment of a highly efficient and selection-free CRISPR gene editing approach for primary endothelial cells (HUVECs) with ribonucleoprotein (RNP) complex. We first optimized an efficient and cost-effective protocol for messenger RNA (mRNA) delivery into primary HUVECs by nucleofection. Nearly 100% transfection efficiency of HUVECs was achieved with EGFP mRNA. Using this optimized DNA-free approach, we tested RNP-mediated CRISPR gene editing of primary HUVECs with three different gRNAs targeting the HIF1A gene. We achieved highly efficient (98%) and biallelic HIF1A knockout in HUVECs without selection. The effects of HIF1A knockout on ECs' angiogenic characteristics and response to hypoxia were validated by functional assays. Our work provides a simple method for highly efficient gene editing of primary endothelial cells (HUVECs) in studies and manipulations of ECs functions.

Protects against Premature Senescence in Human Endothelial Cells

The senescence of vascular endothelial cells (EC) leads to vascular dysfunction. However, the molecular mechanisms of EC senescence and its associated pathophysiological changes have not yet been clearly studied. This study sought to inspect the Chrysanthemum coronarium L. (CC) extract's mechanism in preventing premature senescence of EC. A senescent endothelial cell model was created in human umbilical vein endothelial cells (HUVECs) with 100 µmol/L H₂O₂ treatment for 24 h. The effect of CC on senescent HUVECs was elucidated by measuring the activity of β-galactosidase (SA-β-gal), which exhibits an aging-related phenotype. SA-β-gal activity increased to 13.2 ± 2.85% in H₂O₂-treated HUVECs, whereas this activity was attenuated in the CC group. Immunoblot analyses revealed that p21, p53, and PAI-1 levels increased in the senescent HUVECs; however, the levels decreased in the HUVECs treated with various concentrations of CC (10, 20, and 50 μg/mL). The CC extract reduced the production of reactive oxygen species and reversed the decrease in NO production. Additionally, pretreatment with an Nω-nitro-l-arginine methyl ester (eNOS inhibitor) and nicotinamide (sirtuin 1 inhibitor) inhibited the anti-senescent effect of CC extract in HUVECs. Taken together, this study validated the novel endothelial protective effect of CC extract and its prevention of senescence in HUVECs through the mechanism regulated by eNOS and SIRT1 expression.

Gap Junction-Mediated Transport of Metabolites Between Stem Cells and Vascular Endothelial Cells

We have previously demonstrated that small molecular transfer, such as glucose, between hematopoietic stem cells (HSCs) or mesenchymal stem cells (MSCs) and vascular endothelial cells via gap junctions constitutes an important mechanism of stem cell therapy. Cell metabolites are high-potential small-molecule candidates that can be transferred to small molecules between stem cells and vascular endothelial cells. Here, we investigated the differences in metabolite levels between stem cells (HSCs and MSCs), vascular endothelial cells, and the levels of circulating non-hematopoietic white blood cells (WBCs). The results showed remarkable differences in metabolite concentrations between cells. Significantly higher concentrations of adenosine triphosphate (ATP), guanosine triphosphate (GTP), total adenylate or guanylate levels, glycolytic intermediates, and amino acids were found in HSCs compared with vascular endothelial cells. In contrast, there was no significant difference in the metabolism of MSCs and vascular endothelial cells. From the results of this study, it became clear that HSCs and MSCs differ in their metabolites. That is, metabolites that transfer between stem cells and vascular endothelial cells differ between HSCs and MSCs. HSCs may donate various metabolites, several glycolytic and tricarboxylic acid cycle metabolites, and amino acids to damaged vascular endothelial cells as energy sources and activate the energy metabolism of vascular endothelial cells. In contrast, MSCs and vascular endothelial cells regulate each other under normal conditions. As the existing MSCs cannot ameliorate the dysregulation during insult, exogenous MSCs administered by cell therapy may help restore normal metabolic function in the vascular endothelial cells by taking up excess energy sources from the lumens of blood vessels. Results of this study suggested that the appropriate timing of cell therapy is different between HSCs and MSCs.

The KLF4-p62 axis prevents vascular endothelial cell injury via the mTOR/S6K pathway and autophagy in diabetic kidney disease

INTRODUCTION

Diabetic kidney disease (DKD) is a complication of systemic diabetic microangiopathy, which has a high risk of developing into end-stage renal disease and death. This study explored the mechanism underlying autophagy in DKD vascular endothelial cell injury.

MATERIAL AND METHODS

DKD and vascular endothelial cell injury models were established using Sprague Dawley rats and human umbilical vein endothelial cells (HUVECs). HUVECs overexpressing Kruppel-like factor 4 (KLF4) were constructed by transient transfection of plasmids. Biochemical determination of urinary protein and blood urea nitrogen (BUN), superoxide dismutase (SOD), and creatinine (Scr) levels was performed. Renal pathology was observed by periodic acid-Schiff (PAS) staining. Cell Counting Kit-8 (CCK8), terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL), and immunocytochemistry (ICC) were used to analyse the growth and apoptosis of HUVECs. Microtubule-associated protein light chain 3 (LC3) expression was observed by immunofluorescence (IF). The reactive oxygen species (ROS) levels were measured using flow cytometry. Monocyte chemoattractant protein-1 (MCP-1), KLF4, and tumour necrosis factor alpha (TNF-α) levels were detected using enzyme-linked immunosorbent assay (ELISA). The expression of KLF4, p62 protein, and LC3 was analysed using reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR). S6 kinase (S6K), p70 ribosomal S6 kinase (p-S6K), Beclin1, ATG5, LC3, p62, Caspase-3, mammalian target of rapamycine (mTOR), and phsophorylated mTOR (p-mTOR) expressions were detected by western blotting.

RESULTS

PAS-positive substances (polysaccharide and glycogen) and S6K protein levels increased, and LC3 protein expression decreased in DKD rats. The levels of urinary protein, BUN, and Scr increased, and KLF4 decreased in DKD rats. High glucose (HG) levels decreased the proliferation and increased the apoptosis rate of HUVECs. The expression of ROS, TNF-α, MCP-1, and p62 increased, while the expression of SOD, KLF4, Beclin1, ATG5, and LC3 decreased in HG-induced HUVECs. KLF4 overexpression significantly increased Beclin1, ATG5, and LC3 protein expression and decreased p62 protein expression compared to the oe-NC group in HG-induced HUVECs. KLF4 overexpression inhibits the expression of Caspase-3, p-mTOR, and p-S6K in HG-induced HUVECs.

CONCLUSIONS

KLF4-p62 axis improved vascular endothelial cell injury by regulating inflammation and the mTOR/S6K pathway in DKD.

Triterpenoid saponins of Ilex pubescens against TNF-α induced inflammation and apoptosis in human umbilical vein endothelial cells via autophagy pathway

OBJECTIVES

Triterpenoid saponins of Ilex pubescens (IPTS), the main active components of Ilex pubescens, has a therapeutic effect on atherosclerosis (AS). The ingredients in IPTS that could be intracellularly transported by human umbilical vein endothelial cells (HUVECs) may play an essential role in AS. This study attempted to explore its mechanism from the perspectives of HUVECs' inflammation, apoptosis, and autophagy.

METHODS

By using a tumour necrosis factor-α (TNF-α)-induced HUVECs injury model, cell viability and the expression of intercellular adhesion molecule 1 (ICAM1), matrix metalloproteinase 9 (MMP9), cleave-caspase-3 and cleave-caspase-9, in combination with the results of flow cytometry, JC-1 and Hoechst 33258 staining were investigated to evaluate the anti-inflammatory and anti-apoptotic impact effects of IPTS on HUVECs. Afterwards, the expression of microtubule-associated proteins light chain 3II (LC3II) and sequestosome 1 (p62) was determined to test the effect of IPTS on autophagy. Finally, by adding an autophagy inhibitor 3-methyladenine (3-MA), we investigated whether IPTS exerts anti-inflammatory and anti-apoptotic effects through the autophagy pathway.

KEY FINDINGS

We firstly demonstrated that pretreatment with IPTS could increase the cell viability, maintain the cell morphology and reduce TNF-α-induced inflammation and apoptosis of HUVECs. Moreover, IPTS pretreatment was proved to raise the expression of LC3II /LC3I while decreasing the expression of p62, which indicated that IPTS could activate HUVECs' autophagy. IPTS has been shown for the first time to exert anti-inflammatory and anti-apoptotic effects through autophagy and thereby resisting TNF-α-induced inflammatory injury of HUVECs.

CONCLUSIONS

This study preliminarily confirmed that IPTS ameliorated HUVECs' inflammation and apoptosis by increasing autophagy.

Combining TMZ and SB225002 induces changes of CXCR2 and VEGFR signalling in primary human endothelial cells in vitro

Standard of care therapy for glioblastoma (GBM) consisting of surgical removal, temozolomide (TMZ) and radiotherapy fails to cure the disease and median survival is limited to 15 months. Therapeutic approaches targeting vascular endothelial growth factor (VEGF)-mediated angiogenesis, one of the major drivers of tumour growth, have not prolonged patient survival as reported in clinical studies. Apart from VEGFR signalling, proangiogenic C-X-C motif chemokine receptor 2 (CXCR2) is of special interest as its ligands C-X-C motif chemokine ligand 2 (CXCL2) and interleukin-8 (IL8) are upregulated and associated with reduced survival in GBM patients. As CXCR2 is also expressed by endothelial cells, the aim of the present study was to elucidate the effect of combination therapy on gene and protein expression of primary human endothelial cells (HUVECs). To mimic the GBM specific CXCL2/IL8 oversupply environment [referred to as stimulation (STIM)], HUVECs were treated with a cocktail of CXCL2/IL8 and/or TMZ and/or CXCR2-antagonist SB225002 (SB). In brief, six treatment conditions were utilized: i) Control, ii) STIM (CXCL2/IL8), iii) TMZ + SB, iv) STIM + TMZ, v) STIM + SB, vi) STIM + TMZ + SB followed by either RNA-isolation and RT-qPCR for BAX, BCL2, vascular endothelial growth receptor (VEGFR)1/2, VEGF, CXCR1/2, CXCL2 and IL8 or immunofluorescence staining for VEGFR2 and CXCR2. SB and TMZ led to morphological changes of HUVECs and downregulated antiapoptotic BCL2 in vitro. In addition, gene expression of the alternative proangiogenic CXCL2/IL8/CXCR2 signalling pathway was significantly altered by the combination therapy, while the VEGF/VEGFR1/2 axis was only mildly affected. Furthermore, VEGFR2 and CXCR2 gene and protein expression regulation differed. VEGFR2 was not altered at the gene expression level, while combination therapy with TMZ and SB led to a 74% upregulation of VEGFR2 at the protein level. By contrast, CXCR2 was upregulated 5-fold by the combination therapy at the gene expression level and downregulated by 72.5% at the protein expression level. The present study provided first insights into the molecular changes of two major proangiogenic pathways in primary endothelial cells during treatment with TMZ and SB. Different gene and protein expression levels of the proangiogenic receptors CXCR2 and VEGFR2 in vitro must be taken into consideration in future studies.

[Study on the mechanism of paeonol in improving low-density lipoprotein-induced human vascular endothelial cell injury]

OBJECTIVE

To investigate the effects of paeonol on low-density lipoprotein-induced human vascular endothelial cell injury and its molecular mechanisms.

METHODS

Human umbilical vein endothelial cells (HUVECs) were divided into 9 groups, normal control (NC) group, ox-LDL group (100 ng/L ox-LDL), low, medium, and high-dose paeonol groups (60 μmol/L, 120 μmol/L, 240 μmol/L paeonol+100 ng/L ox-LDL), ox-LDL+small interfering RNA negative control (si-NC) group, ox-LDL+circ_0003204 small interfering RNA (si-circ_0003204) group, middle dose group+ox-LDL+circ_0003204 overexpression negative control (pcDNA-NC) group, middle dose group+ox-LDL+circ_0003204 overexpression (pcDNA-circ_0003204) group, three replicate wells in each group. MTT flow cytometry, and Western blot were used to detect cell proliferation, apoptosis and protein (CDK2, Bcl2, p27, Bax) expressions, respectively. Malondialdehyde (MDA) and superoxide dismutase (SOD) kit were used to detect MDA content and SOD activity; real-time quantitative PCR (RT-qPCR) was used to detect the expression of circ_0003204.

RESULTS

Compared with the NC group, the proliferation activity, protein expressions of CDK2 and Bcl2, and SOD activity of HUVECs in the ox-LDL group were decreased significantly (P＜0.05), and the apoptosis rate, protein expressions of p27 and Bax, MDA content, and circ_0003204 expression were increased significantly (P＜ 0.05). Compared with the ox-LDL group, the proliferation activity, protein (CDK2, Bcl2) expressions and SOD activity of HUVECs in the low, medium and high dose paeonol groups were increased significantly (P＜0.05), and the apoptosis rate, protein (p27, Bax) expressions, MDA content And circ_0003204 expression were decreased significantly (P＜ 0.05). Compared with ox-LDL+si-NC group, the proliferation activity, protein (CDK2, Bcl2) expressions, SOD activity of HUVECs in ox-LDL+si-circ_0003204 group were increased significantly (P＜0.05), the apoptosis rate, protein (p27, Bax) expressions, and the content of MDA were decreased significantly (P＜0.05). Compared with the middle-dose+ox-LDL+pcDNA-NC group, the HUVECs proliferation activity, protein (CDK2, Bcl2) expressions, and SOD activity in the middle-dose+ox-LDL+pcDNA-circ_0003204 group were decreased significantly (P＜0.05), and the levels of circ_0003204, apoptosis rate, protein (p27, Bax) expressions and MDA content were increased significantly (P＜0.05).

CONCLUSION

Paeonol can inhibit ox-LDL-induced apoptosis and oxidative stress of human umbilical vein endothelial cells, and alleviate human umbilical vein endothelial cell injury. The mechanism of action may be related to the down-regulation of circ_0003204 expression.

Transmembrane Water Transport and Intracellular Ice Formation of Human Umbilical Vein Endothelial Cells During Freezing

Long-term cryopreservation of human umbilical vein endothelial cells (HUVECs) is important and beneficial for a variety of biomedical research and applications. In this study, we investigated HUVEC's cryobiological characteristics and parameters that are indispensable for predicting and determining an optimal cooling rate to prevent lethal intracellular ice formation (IIF) and severe cell dehydration during the cryopreservation processes. The parameters include cell membrane hydraulic conductivity (i.e., cell membrane water permeability), L_p, cell membrane water permeability activation energy, E_lp, and osmotically inactive volume of a cell V_b. Cryomicroscopy was used to study the IIF phenomena and cell volume excursion at various cooling rates, 1, 10, and 20°C/min, respectively, based on which the cryobiological parameters were determined using biophysical and mathematical models. Results from this research work laid an important cryobiological foundation for the optimization of HUVEC's cryopreservation conditions.

Fabrication of a Cell-Friendly Poly(dimethylsiloxane) Culture Surface via Polydopamine Coating

In this study, we fabricated a poly(dimethylsiloxane) (PDMS) surface coated with polydopamine (PDA) to enhance cell adhesion. PDA is well known for improving surface adhesion on various surfaces due to the abundant reactions enabled by the phenyl, amine, and catechol groups contained within it. To confirm the successful surface coating with PDA, the water contact angle and X-ray photoelectron spectroscopy were analyzed. Human umbilical vein endothelial cells (HUVECs) and human-bone-marrow-derived mesenchymal stem cells (MSCs) were cultured on the PDA-coated PDMS surface to evaluate potential improvements in cell adhesion and proliferation. HUVECs were also cultured inside a cylindrical PDMS microchannel, which was constructed to mimic a human blood vessel, and their growth and performance were compared to those of cells grown inside a rectangular microchannel. This study provides a helpful perspective for building a platform that mimics in vivo environments in a more realistic manner.

Absorption characteristics of ilexgenin A and ilexsaponin B1 in human umbilical vein endothelial cells after administration of the total triterpenoid saponin from Ilex Pubescens

Ilex pubescens, a famous Chinese herbal medicine, frequently treated with cardiovascular disease in South China. In this study, we aim to explore the absorption properties of ilexgenin A (C1) and ilexsaponin B1 (C3) in vascular endothelial cells after administration of the total triterpenoid saponin from Ilex Pubescens (IPTS) and clarify the possible transport mechanisms. A UPLC-qTOF-MS/MS was used to identify the components in IPTS that could be intracellular transported by HUVECs. Afterwards, a rapid, high selective and sensitive methods was established to simultaneously quantify the concentration of C1 and C3 in HUVECs after administration of IPTS. The results demonstrated that pretreatment with IPTS could promote the survival of HUVECs and reduce the damage of TNF-α to HUVECs. Among the main 11 components in IPTS, 8 components could be absorbed by HUVECs, including 7 triterpenoids and 1 phenolic acid. The uptake of C1 and C3 by HUVECs was in a time-, temperature- and concentration-dependent manner, indicating the participation of passive diffusion and active transportation mechanisms. The two triterpenoid saponins all exhibited rapid absorption and bimodal phenomenon in concentration-time profiles, and equilibrium could be achieved after 6 hours. Furthermore, C1 and C3 intracellular transportation was regulated by serum proteins, sodim-dependent glucose transporter 1 (SGLT1) and P-glycoprotein (P-gp). The current research for the first time demonstrates the in vitro pharmacokinetics characteristics of C1 and C3 in HUVECs lines, which could supply new way of understanding of treatment of cardiovascular diseases.

[Protective effects of estrogen modified hBMSC on HG-induced injury of vascular endothelial cells]

Objective: To investigate the protective effects and potential mechanisms of estrogen modified human bone marrow mesenchymal stem cells (hBMSC) on high glucose (HG)-induced injury of vascular endothelial cells. Methods: hBMSCs were cultured under 30 mmol/l glucose to establish a high glucose model (HG), and then were divided into four groups as following: HG group (HG control, without any treatment), HG+E2 group (cells were treated with 20 μmol/L estrogen), HG+E2+ Triciribine group (cells were pretreated with 5 μmol/L protein kinase B (PKB/Akt) inhibitor for 45 min, and then modified by 20 μmol/L estrogen), and NG group (cells were cultured under normal conditions). After 12 h treatment, the cell viability of hBMSC was detected by CCK8 assay, and the contents of NO, VEGF and IL8 in the supernatant of cultured medium in each group were detected by nitrate reductase and ELISA assay (n=6). After 48 h, the expression levels of endothelial nitric oxide synthase (eNOS) and phosphorylated eNOS (p-eNOS) were detected by Western blot (n=3). In addition, the cell supernatant of each group was further extracted as conditioned medium to culture HUVECs, and the cells were subsequently divided into HG-CM group (HUVECs were treated with HG group's conditioned medium), HG+E2-CM group (HUVECs were treated with HG+E2 group's conditioned medium), HG+E2+Triciribine-CM group (HUVECs were treated with HG+E2+ Triciribine group's conditioned medium) and HG-H group (HUVEC were cultured under HG condition, which were treated with final concentration 30 mmol/l glucose). The cell viability of HUVECs in each group was detected by CCK8 assay after 12 h cultured (n=6). After 24 h treatment, the apoptosis rate of HUVECs in each group was detected by flow cytometry (n=3). Furthermore, the migration rate of HUVECs in each group was observed by wound healing assay after 48 h cultured (n=3). Results: Compared with NG group, the cell viability and eNOS protein phosphorylation level of hBMSC in HG group and the contents of NO, VEGF and IL-8 in the supernatant of cultured medium were decreased (P<0.05). Compared with HG group, the cell viability and eNOS protein phosphorylation level in HG+E2 group and the contents of NO, VEGF and IL-8 in cultured medium supernatant were increased significantly (P<0.05), whereas pre-treatment of hBMSC cells with a Akt inhibitor Triciribine, the above indexes showed reverse changes (P<0.05). Furthermore, compared with HG-CM group, the cell viability and migration ability (P<0.05) of HUVECs in HG+E2-CM group were increased significantly (P<0.05), and the proportion of apoptosis was decreased (P<0.05). While compared with HG+E2-CM group, the cell viability and migration ability of HUVECs in HG+E2+Triciribine-CM group were decreased (P<0.05), and the proportion of apoptosis was increased (P<0.05). Conclusion: Estrogen may promote the secretion of NO, VEGF and IL-8 by activating the Akt/eNOS signaling pathway of hBMSC cells, increase the cell viability and migration ability of HUVECs and inhibit the occurrence of apoptosis, play a protective role against the injury of HUVECs induced by HG condition.

Combination stem cell therapy using dental pulp stem cells and human umbilical vein endothelial cells for critical hindlimb ischemia

Narrowing of arteries supplying blood to the limbs provokes critical hindlimb ischemia (CLI). Although CLI results in irreversible sequelae, such as amputation, few therapeutic options induce the formation of new functional blood vessels. Based on the proangiogenic potentials of stem cells, in this study, it was examined whether a combination of dental pulp stem cells (DPSCs) and human umbilical vein endothelial cells (HUVECs) could result in enhanced therapeutic effects of stem cells for CLI compared with those of DPSCs or HUVECs alone. The DPSCs+ HUVECs combination therapy resulted in significantly higher blood flow and lower ischemia damage than DPSCs or HUVECs alone. The improved therapeutic effects in the DPSCs+ HUVECs group were accompanied by a significantly higher number of microvessels in the ischemic tissue than in the other groups. In vitro proliferation and tube formation assay showed that VEGF in the conditioned media of DPSCs induced proliferation and vessel-like tube formation of HUVECs. Altogether, our results demonstrated that the combination of DPSCs and HUVECs had significantly better therapeutic effects on CLI via VEGF-mediated crosstalk. This combinational strategy could be used to develop novel clinical protocols for CLI proangiogenic regenerative treatments. [BMB Reports 2022; 55(7): 336-341].

Pramlintide: An Amylin Analogue Protects Endothelial Cells against Oxidative Stress through Regulating Oxidative Markers and NF-κb Expression

Background:

Oxidative stress has a prominent role in the pathogenesis of diabetes complications. Pramlintide is an injectional amylin analogue used for the treatment of type 1 and type 2 diabetic patients. The present investigation evaluated the effect of pramlintide against oxidative damage induced by hydrogen peroxide (H₂O₂) in human umbilical vein endothelial cells (HUVECs).

Methods:

Cell viability was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Hydroperoxides level, ferric reducing antioxidant power (FRAP), and expression of transcription factor NF-κB were measured in HUVECs that pretreated with pramlintide and, then exposed to H₂O₂.

Results:

Pramlintide significantly decreased the cytotoxicity caused by H₂O₂ at the concentrations of 5 and 10 μg/mL. Pretreatment of HUVECs with pramlintide reduced hydroperoxides and increased FRAP value in intra- and extra-cellular mediums at different concentration ranges compared with H₂O₂ stimulated cells. Pramlintide (10 μg/mL) remarkably ameliorated the expression of NF-κB gene after 1, 3 and 24 h exposure to H₂O₂.

Conclusions:

Findings of the current investigation displayed that pramlintide may act as a protective against oxidative conditions in endothelial cells through modulation of oxidative markers and transcription factor NF-κB.

An ApoA-I Mimic Peptide of 4F Promotes SDF-1α Expression in Endothelial Cells Through PI3K/Akt/ERK/HIF-1α Signaling Pathway

Atherosclerosis (AS) seriously impairs the health of human beings and is manifested initially as endothelial cells (ECs) impairment and dysfunction in vascular intima, which can be alleviated through mobilization of endothelial progenitor cells (EPCs) induced by stromal-cell-derived factor-1α (SDF-1α). A strong inverse correlation between HDL and AS has been proposed. The aim of the present work is to investigate whether 4F, an apolipoprotein A-I (apoA-I, major component protein of HDL) mimic peptide, can upregulate SDF-1α in mice and human umbilical vein endothelial cells (HUVECs) and the underlying mechanism. The protein levels of SDF-1α were measured by ELISA assay. Protein levels of HIF-1α, phosphorylated Akt (p-Akt), and phosphorylated ERK (p-ERK) were evaluated by Western blotting analysis. The results show that L-4F significantly upregulates protein levels of HIF-1α, Akt, and ERK, which can be inhibited by the PI3K inhibitor, LY294002, or ERK inhibitor, PD98059, respectively. Particularly, LY294002 can downregulate the levels of p-ERK, while PD98059 cannot suppress that of p-Akt. D-4F can upregulate the levels of HIF, p-Akt, and p-ERK in the abdominal aorta and inferior vena cava from mice. These results suggest that 4F promotes SDF-1α expression in ECs through PI3K/Akt/ERK/HIF-1α signaling pathway.

Cyclosporin-A reduced the cytotoxicity of propranolol in HUVECs via p38 MAPK signaling

Propranolol (PROP) is a nonselective β-adrenergic receptor antagonist used to treat hypertension and cardiac arrhythmias. Oral administration of PROP has recently emerged as a new treatment modality for hemangiomas. However, the side effects of PROP at the cellular level have not been adequately described.The present study investigates and highlights the mechanisms of coupling of the drugs cyclosporin-A (CyA) and PROP on cell proliferation and the occurrence of apoptosis. It also relays the antioxidant effect of PROP on human umbilical vein endothelial cells (HUVECs).HUVECs were treated with CyA and PROP. At 24 hours after treatment, the levels of reactive oxygen species (ROS), cell proliferation, and apoptosis were determined using the ROS kit, MTT assay, and Annexin V staining. In addition, the related proteins of phospho-p38 mitogen-activated protein kinase were determined by western blotting. Subsequently, HUVECs pretreated with CyA or PROP were treated with the p38 inhibitor (SB203580). Finally, the ROS level, cell proliferation, and apoptosis were measured again in both active HUVECs and HUVECs, in which the p38 proteins were inhibited.The combination of CyA and PROP reversed the effect of CyA on cell viability, reduced the ROS level and the cell apoptosis induced by PROP. Moreover, inhibition of p38 protein catalase activity immediately stopped the effect of CyA-propranolol in HUVECs.The effect of the CyA-propranolol combination on HUVECs is associated with the p38 pathway changes, which is proven to be a potential chemotherapeutic agent that minimizes the side effects of PROP in hemangioma therapy.

microRNA-10a-5p from gastric cancer cell-derived exosomes enhances viability and migration of human umbilical vein endothelial cells by targeting zinc finger MYND-type containing 11

Tumor-derived exosomes (exo) could modulate the biological behaviors of human umbilical vein endothelial cells (HUVECs). Here, the role of microRNA (miR)-10a-5p-modified gastric cancer (GC) cells-derived exo for HUVECs was studied. GC tissue specimens were collected, and miR-10a-5p and zinc finger MYND-type containing 11 (ZMYND11) levels were determined. HUVECs interfered with ZMYND11 or miR-10a-5p-related oligonucleotides. Exo was extracted from GC cells (HGC-27 exo), and miR-10a-5p mimic-modified HGC-27 exo were co-cultured with HUVECs. HUVECs viability, migration and angiogenesis were evaluated, and miR-10a-5p/ZMYND11 crosstalk was explored. It was observed that GC patients had raised miR-10a-5p and reduced ZMYND11, and miR-10a-5p negatively mediated ZMYND11 expression. Suppression of miR-10a-5p or overexpression of ZMYND11 inhibited viability, migration and tube formation ability of HUVECs. Notably, miR-10a-5p mimic-modified HGC-27 exo enhanced the viability, migration and tube formation ability of HUVECs, but this effect was impaired after up-regulating ZMYND11. In summary, miR-10a-5p from GC cells-derived exo enhances viability and migration of HUVECs by suppressing ZMYND11.

A comparative assessment of e-cigarette aerosol extracts and tobacco cigarette smoke extracts on in vitro endothelial cell inflammation response

With the development of the times, electronic cigarettes (e-cigarettes) are being received by more and more people. We compared the different effects of e-cigarettes and tobacco cigarettes on human umbilical vein endothelial cells (HUVECs) treated with the typical e-cigarette aerosol extracts (ECA) and cigarette smoking extracts (CS) sourced from commercial retail stores. HUVECs were treated with different kinds of ECA or CS with different nicotinic concentrations (0.03125, 0.125, 0.5, 2, 8, or 32 μg/mL). Cell viability was examined by the MTT assay. The cell apoptosis was investigated by acridine orange (AO) and Hoechst 33258 staining. The RT-PCR and western blot assays were used to analyze the adhesion molecules and inflammation cytokines released by HUVECs. Furthermore, the intracellular reactive oxygen species (ROS) was observed by fluorescence microscopy. Our data showed that the CS (nicotine concentration at 0.125 μg/mL could decrease the viability of HUVECs by 71%, but not the four kinds of ECA. The apoptotic ratio was about 32.5% in the CS group. No matter the levels of adhesion molecules, inflammation cytokines or ROS, they were higher in CS groups than in ECA groups. Overall, the four kinds of e-cigarettes induced significantly less cytotoxicity than the commercially available tobacco cigarettes in HUVECs. The CS showed the most severe impact on HUVECs. ECA might provide a harm reduction measure, especially in cardiovascular risk, after people switch from tobacco cigarettes to e-cigarettes.

Disturbance of Vancomycin Infusion Flow during Multidrug Infusion: Influence on Endothelial Cell Toxicity

Background: Phlebitis is a common side effect of vancomycin peripheral intravenous (PIV) infusion. As only one PIV catheter is frequently used to deliver several drugs to hospitalized patients through the same Y-site, perturbation of the infusion flow by hydration or other IV medication may influence vancomycin exposure to endothelial cells and modulate toxicity. Methods: We assessed the toxicity of variations in vancomycin concentration induced by drug mass flow variations in human umbilical vein endothelial cells (HUVECs), simulating a 24 h multi-infusion therapy on the same line. Results were expressed as the percentage of viable cells compared with a 100% control, and the Kruskal–Wallis test was used to assess the toxicity of vancomycin. Results: Our results showed that variations in vancomycin concentration did not significantly influence local toxicity compared to a fixed concentration of vancomycin. Nevertheless, the loss of cell viability induced by mechanical trauma mimicking multidrug infusion could increase the risk of phlebitis. Conclusion: To ensure that vancomycin-induced phlebitis must have other causes than variation in drug mass flow, further in vitro experiments should be performed to limit mechanical stress to frequent culture medium change.

Indoxyl Sulfate Elevated Lnc-SLC15A1-1 Upregulating CXCL10/CXCL8 Expression in High-Glucose Endothelial Cells by Sponging MicroRNAs

Cardiovascular disease (CVD) is the leading cause of mortality in diabetes mellitus (DM). Immunomodulatory dysfunction is a primary feature of DM, and the emergence of chronic kidney disease (CKD) in DM abruptly increases CVD mortality compared with DM alone. Endothelial injury and the accumulation of uremic toxins in the blood of DM/CKD patients are known mechanisms for the pathogenesis of CVD. However, the molecular factors that cause this disproportional increase in CVD in the DM/CKD population are still unknown. Since long non-protein-coding RNAs (lncRNAs) play an important role in regulating multiple cellular functions, we used human endothelial cells treated with high glucose to mimic DM and with the uremic toxin indoxyl sulfate (IS) to mimic the endothelial injury associated with CKD. Differentially expressed lncRNAs in these conditions were analyzed by RNA sequencing. We discovered that lnc-SLC15A1-1 expression was significantly increased upon IS treatment in comparison with high glucose alone, and then cascaded the signal of chemokines CXCL10 and CXCL8 via sponging miR-27b, miR-297, and miR-150b. This novel pathway might be responsible for the endothelial inflammation implicated in augmenting CVD in DM/CKD and could be a therapeutic target with future clinical applications.

Human antigen R promotes angiogenesis of endothelial cells cultured with adipose stem cells derived exosomes via overexpression of vascular endothelial growth factor in vitro

Recent studies showed that exosomes obtained from adipose-derived stem cells (ADSCs) could improve the angiogenesis of fat grafts via overexpression of vascular endothelial growth factor (VEGF). Human antigen R (HuR) promotes the expression of VEGF in many cancers, but the effect of HuR in normal endothelial cells in the presence of ADSC-derived exosomes remains unclear. We aimed to investigate the effect of HuR on the expression of VEGF and angiogenesis of human umbilical vein endothelial cells (HUVECs) cultured with ADSCs-derived exosomes. The HuR-overexpressed HUVECs (HuR-HUVECs) were cocultured with ADSCs-derived exosomes. qRT-PCR and Western blotting were performed to examine the stability and expression of VEGF-A mRNA and protein. The proliferation, migration, and proangiogenic capacity of HuR-HUVECs were evaluated using cell counting kit-8 (CCK-8), scratch wound healing, and Matrigel tube formation assay. qRT-PCR showed that HuR-HUVECs had higher expression and slower attenuation of VEGF-A mRNA. Western blotting confirmed higher expression of VEGF-A in HuR-HUVECs. CCK-8, scratch wound healing, and Matrigel tube formation assay demonstrated an increased proangiogenic effect in HuR-HUVECs. HuR promotes angiogenesis of HUVECs cocultured with ADSCs-derived exosomes via stabilization and overexpression of VEGF in vitro. The HuR/VEGF pathway is an important regulatory mechanism of angiogenesis in endothelial cells.