Simulated Microgravity Increases the Permeability of HUVEC Monolayer through Up-Regulation of Rap1GAP and Decreased Rap2 Activation

Space microgravity condition has great physiological influence on astronauts’ health. The interaction of endothelial cells, which control vascular permeability and immune responses, is sensitive to mechanical stress. However, whether microgravity has significant effects on the physiological function of the endothelium has not been investigated. In order to address such a question, a clinostat-based culture model with a HUVEC monolayer being inside the culture vessel under the simulated microgravity (SMG) was established. The transmittance of FITC-tagged dextran was used to estimate the change of integrity of the adherens junction of the HUVEC monolayer. Firstly, we found that the permeability of the HUVEC monolayer was largely increased after SMG treatment. To elucidate the mechanism of the increased permeability of the HUVEC monolayer under SMG, the levels of total expression and activated protein levels of Rap1 and Rap2 in HUVEC cells, which regulate the adherens junction of endothelial cells, were detected by WB and GST pull-down after SMG. As the activation of both Rap1 and Rap2 was significantly decreased under SMG, the expression of Rap1GEF1 (C3G) and Rap1GAP in HUVECs, which regulate the activation of them, was further determined. The results indicate that both C3G and Rap1GAP showed a time-dependent increase with the expression of Rap1GAP being dominant at 48 h after SMG. The down-regulation of the expression of junctional proteins, VE-cadherin and β-catenin, in HUVEC cells was also confirmed by WB and immunofluorescence after SMG. To clarify whether up-regulation of Rap1GAP is necessary for the increased permeability of the HUVEC monolayer after SMG, the expression of Rap1GAP was knocked down by Rap1GAP-shRNA, and the change of permeability of the HUVEC monolayer was detected. The results indicate that knock-down of Rap1GAP reduced SMG-induced leaking of the HUVEC monolayer in a time-dependent manner. In total, our results indicate that the Rap1GAP-Rap signal axis was necessary for the increased permeability of the HUVEC monolayer along with the down-regulation of junctional molecules including VE-cadherin and β-catenin.

Interaction between Flavonoids and Carotenoids on Ameliorating Oxidative Stress and Cellular Uptake in Different Cells

Flavonoids (quercetin, luteolin) and carotenoids (lycopene, lutein) were combined at different molecular ratios in a total concentration of 8 μM to investigate their antioxidant interactions. Cellular uptake of carotenoids, the expression of carotenoid transporters, the ROS scavenging ability, and antioxidant enzymes activities were compared in HUVEC, Caco-2, and L-02 cells. Combinations with flavonoids in the majority showed stronger antioxidant activity. Lycopene combined with quercetin at ratio 1:5 showed stronger ROS scavenging activities, increased 18, 12, and 12 Cellular antioxidant activity (CAA) units in HUVEC, Caco-2, and L-02 cells, respectively, and promoted SOD and CAT activities than individual component. The cell uptake of carotenoids was enhanced by flavonoids in antioxidant synergistic groups, while dampened by flavonoids in antagonistic groups in HUVEC cells. The synergistic group (lycopene:quercetin = 1:5) increased lycopene uptake by 271%, while antagonistic group (lutein:quercetin = 5:1) decreased lutein uptake by 17%. Flavonoids modulated the effects of carotenoids on the expression of active transporters scavenger receptor class B type I (SR-BI) or Niemann-Pick C1-like 1 (NPC1L1). The synergistic group (lycopene:quercetin = 1:5) increased the expression of SR-BI compared to individual lycopene treatment in HUVEC and Caco-2 cells. Thus, a diet rich in both flavonoids and lycopene possesses a great antioxidant activity, especially if a higher amount of flavonoids is included.

Identification of Pathways and Key Genes in Carotid Atherosclerosis by Bioinformatics Analysis

Purpose: Carotid atherosclerosis is a serious vascular disease, leading to various cerebrovascular diseases. Methods: Gene expression profile of GSE100927 was selected to conduct differentially expressed genes. Then we performed protein-protein interactions, Gene ontology, and Kyoto Encyclopedia of Genes and Genomes analysis. Then we used HUVEC, HAVSMC, and THP-1 induced macrophages cells to conduct experimental verification. The experimental groups were as follows: Control group, Solvent control group, and Palmitic acid group. We measured the levels of reactive oxygen species in three cells via flow cytometer or fluorescence microscope. Then we detected apoptosis of HUVEC cells and HAVSMC cells or observed nucleus of THP-1 induced macrophages cells. Results: We selected male carotid atherosclerosis, with 10 control samples and 21 atherosclerosis samples. The results of pathway enrichment showed that “Toll-like receptor signaling pathway” ranked first. We chose IL1β, CCL4, SPP1, CCL3, IRF5. MMP7 and MMP9 for experimental verification. Palmitic acid increased the reactive oxygen species levels and the apoptosis rates of HUVEC cells and HAVSMC cells while increasing the activity of THP-1 induced macrophages cells, and it cannot increase the level of reactive oxygen species, and shrink the nucleus. Palmitic acid increased mRNA levels of IL1β, CCL4, SPP1, CCL3, IRF5. MMP7 and MMP9 in HUVEC cells and THP-1 induced macrophages, and increased the mRNA levels of CCL4 and MMP9 in HAVSMC cells，not changed the mRNA level of IRF5. Conclusion: IL1β，CCL3, CCL4, SPP1, IRF5, MMP7, and MMP9 are significant markers of carotid atherosclerosis.

Bioinformatics and Network Pharmacology Identify the Therapeutic Role and Potential Mechanism of Melatonin in AD and Rosacea

Rosacea is significantly associated with dementia, particularly Alzheimer’s disease (AD). However, the common underlying molecular mechanism connecting these two diseases remains limited. This study aimed to reveal the common molecular regulatory networks and identify the potential therapeutic drugs for rosacea and AD. There were 747 overlapped DEGs (ol-DEGs) that were detected in AD and rosacea, enriched in inflammation-, metabolism-, and apoptosis-related pathways. Using the TF regulatory network analysis, 37 common TFs and target genes were identified as hub genes. They were used to predict the therapeutic drugs for rosacea and AD using the DGIdb/CMap database. Among the 113 predicted drugs, melatonin (MLT) was co-associated with both RORA and IFN-γ in AD and rosacea. Subsequently, network pharmacology analysis identified 19 pharmacological targets of MLT and demonstrated that MLT could help in treating AD/rosacea partly by modulating inflammatory and vascular signaling pathways. Finally, we verified the therapeutic role and mechanism of MLT on rosacea in vivo and in vitro. We found that MLT treatment significantly improved rosacea-like skin lesion by reducing keratinocyte-mediated inflammatory cytokine secretion and repressing the migration of HUVEC cells. In conclusion, this study contributes to common pathologies shared by rosacea and AD and identified MLT as an effective treatment strategy for rosacea and AD via regulating inflammation and angiogenesis.

Clinical significance of microRNA-126 in Coronary artery disease patients

Background Coronary artery disease (CAD) is major public health problem and the leading cause of premature death all over the world. Early diagnosis with adequate management of CAD patients can significantly reduce morbidity and mortality rate. Purpose The purpose of this study was to explore the clinical significance of plasma miR-126 as a biomarker of stable angina pectoris patients and investigated the protective effects of hypoxic exposed HUVEC cell injury. Methods Angiographically confirmed 127 stable coronary artery (CAD) patients, 55 healthy subjects and 18hours hypoxic (1% O2) HUVEC cells were included in this study. Results The expression of miR-126 levels were remarkably down-regulated in stable CAD patients and hypoxic exposed HUVEC cells as compared with controls (p<0.001). Circulating plasma miR-126 was able to accurately differentiated stable CAD patients from healthy subjects with high sensitivity and specificity (AUC 0.928). The caspase-3 activity, apoptosis rate, LDH levels and intracellular ROS generation were significantly increased in 24hours hypoxic exposed HUVEC cells than normal control cells (p<0.001). On the contrary, over expressions of miR-126 were evidently reduced caspase-3 activity, apoptosis rate, LDH levels, intracellular ROS production and significantly improved HUVEC cellular viability (p<0.001). Moreover, TNF receptor-associated factor 6 (TRAF6) expressions were markedly increased in Hypoxic induced HUVEC cells, whereas mimic expression of miR-126 significantly decreased TRAF6 expression. Conclusion Down-regulated miR-126 may consider as a potential risk factor for stable CAD patients and it may used as a possible biomarker for early evaluation of CAD patients. Mimic expression of miR-126 remarkably decreased caspase-3 activity, LDH secretions, ROS levels and markedly improved HUVEC cellular viability by down-regulating TRAF6 expression, suggesting a newer therapeutic target for CAD patients. FUNDunding Acknowledgement Type of funding sources: None.

SARS-CoV-2 Coronavirus Spike Protein-Induced Apoptosis, Inflammatory, and Oxidative Stress Responses in THP-1-Like-Macrophages: Potential Role of Angiotensin-Converting Enzyme Inhibitor (Perindopril)

A purified spike (S) glycoprotein of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) coronavirus was used to study its effects on THP-1 macrophages, peripheral blood mononuclear cells (PBMCs), and HUVEC cells. The S protein mediates the entry of SARS-CoV-2 into cells through binding to the angiotensin-converting enzyme 2 (ACE2) receptors. We measured the viability, intracellular cytokine release, oxidative stress, proinflammatory markers, and THP-1-like macrophage polarization. We observed an increase in apoptosis, ROS generation, MCP-1, and intracellular calcium expression in the THP-1 macrophages. Stimulation with the S protein polarizes the THP-1 macrophages towards proinflammatory futures with an increase in the TNFα and MHC-II M1-like phenotype markers. Treating the cells with an ACE inhibitor, perindopril, at 100 µM reduced apoptosis, ROS, and MHC-II expression induced by S protein. We analyzed the sensitivity of the HUVEC cells after the exposure to a conditioned media (CM) of THP-1 macrophages stimulated with the S protein. The CM induced endothelial cell apoptosis and MCP-1 expression. Treatment with perindopril reduced these effects. However, the direct stimulation of the HUVEC cells with the S protein, slightly increased HIF1α and MCP-1 expression, which was significantly increased by the ACE inhibitor treatment. The S protein stimulation induced ROS generation and changed the mitogenic responses of the PBMCs through the upregulation of TNFα and interleukin (IL)-17 cytokine expression. These effects were reduced by the perindopril (100 µM) treatment. Proteomic analysis of the S protein stimulated THP-1 macrophages with or without perindopril (100 µM) exposed more than 400 differentially regulated proteins. Our results provide a mechanistic analysis suggesting that the blood and vascular components could be activated directly through S protein systemically present in the circulation and that the activation of the local renin angiotensin system may be partially involved in this process.GraphicalSuggested pathways that might be involved at least in part in S protein inducing activation of inflammatory markers (red narrow) and angiotensin-converting enzyme inhibitor (ACEi) modulation of this process (green narrow).

Adhesion and Stiffness of Detached Breast Cancer Cells In Vitro: Co-Treatment with Metformin and 2-Deoxy-d-glucose Induces Changes Related to Increased Metastatic Potential

Metastatic cancer cells can overcome detachment-induced cell death and can proliferate in anchorage-independent conditions. A recent study revealed that a co-treatment with two drugs that interfere with cell metabolism, metformin and 2-deoxy-D-glucose, promotes detachment of viable MDA-MB-231 breast cancer cells. In the present study, we analyzed if these detached viable MDA-MB-231 cells also exhibit other features related to cancer metastatic potential, i.e., if they are softer and more prone to adhere to epithelial cells. The cell mechanics of attached cells and floating cells were analyzed by optical tweezers and cell deformability cytometry, respectively. The adhesion was assessed on a confluent monolayer of HUVEC cells, with MDA-MB-231 cells either in static conditions or in a microfluidic flow. Additionally, to test if adhesion was affected by the state of the epithelial glycocalyx, HUVEC cells were treated with neuraminidase and tunicamycin. It was found that the treated MDA-MB-231 cells were more prone to adhere to HUVEC cells and that they were softer than the control, both in the floating state and after re-seeding to a substrate. The changes in the HUVEC glycocalyx, however, did not increase the adhesion potential of MDA-MB-231.

Abstract P107: Anti- Mir-510 In The Treatment Of Essential Hypertension By Using Hypertensive Rats

Introduction: Hypertension (HTN) is one of the major public health complications throughout the world. Although progress has been made in HTN research, early diagnosis and treatment of HTN are yet to be flourished. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression in many diseases including HTN. According to our previous report, there is direct evidence showing that miR-510 is involved in HTN. Hypothesis: We assessed the hypothesis that to decipher the critical pathways of miR-510 and PTEN in regulation of PI3K/AKT Pathways, so it can be used as a therapeutic pathway as well as biomarker. Finally, we intend to study how anti-miR-510 reduces the HTN in the hypertensive induced rat model. Methodology: Proliferation, migration, invasion and apoptosis capacity of miR-510, Anti-miR-510, PTEN and eNOS were evaluated in HUVEC Cells. The expression pattern of miR-510, anti-miR-510 and eNOS, PTEN are analyzed by qPCR and western blot The relationship between miR-510, Anti-miR-510 and PTEN are investigated by luciferase assay Deoxycorticosterone acetate (DOCA) of 70mg/kg and 1% NaCl salt induced hypertension model (Sprague Dawley rats) was used in this study. According to the dose dependent study, anti-miR-510 was administered intravenously. Histological analyses are performed to examine the hypertrophy by using cardiac tissues fixed in 1% paraformaldehyde. Results and conclusion: Our results suggested that miR-510 can directly influence the PTEN expressions in HUVEC cells. Furthermore, the in vitro experiments clearly indicated that miR-510/PI3K/AKT/PTEN axis involved in HTN. Anti-miR-510 delivery can reduce the progression of HTN in the hypertensive induced rat model. Though miR-510 is involved in HTN, but its molecular mechanism is almost unknown. So, these analyses suggested that the correlation between miR-510, PTEN, anti-miR-510 are the critical step in gene expression and regulations. Thus, all these analyses could lead in identification of therapeutic target and non-invasive biomarker for HTN. Our in vivo experiments suggesting that anti-miR-510 may act as a novel therapeutic molecule for HTN treatment.