CAD increases the long noncoding RNA PUNISHER in small extracellular vesicles and regulates endothelial cell function via vesicular shuttling

Section 11: Evaluation and Management of Patients With Heart Failure and Preserved Left Ventricular Ejection Fraction

Surgical collateralization: The hidden mechanism for improving prognosis in chronic coronary syndromes

Co-Existence of Carotid Artery Disease, Renal Artery Stenosis, and Lower Extremity Peripheral Arterial Disease in Patients With Coronary Artery Disease

Screening for the Presence of Coronary Artery Disease

Percutaneous coronary intervention with peripheral artery disease in the contemporary era: Still life or limb?

Vascular endothelial growth factor A (VEGF-A) is a potent inducer of angiogenesis. We now show that VEGF-A-induced adhesion and migration of human endothelial cells are dependent on the integrin alpha9beta1 and that VEGF-A is a direct ligand for this integrin. Adhesion and migration of these cells on the 165 and 121 isoforms of VEGF-A depend on cooperative input from alpha9beta1 and the cognate receptor for VEGF-A, VEGF receptor 2 (VEGF-R2). Unlike alpha3beta1or alphavbeta3 integrins, alpha9beta1 was also found to bind the 121 isoform of VEGF-A. This interaction appears to be biologically significant, because alpha9beta1-blocking antibody dramatically and specifically inhibited angiogenesis induced by VEGF-A165 or -121. Together with our previous findings that alpha9beta1 directly binds to VEGF-C and -D and contributes to lymphangiogenesis, these results identify the integrin alpha9beta1 as a potential pharmacotherapeutic target for inhibition of pathogenic angiogenesis and lymphangiogenesis.

Vascular endothelial growth factor (VEGF) and reactive oxygen species (ROS) play critical roles in vascular physiology and pathophysiology. We have demonstrated previously that NADPH oxidase-derived ROS are required for VEGF-mediated migration and proliferation of endothelial cells. The goal of this study was to determine the extent to which VEGF signaling is coupled to NADPH oxidase activity. Human umbilical vein endothelial cells and/or human coronary artery endothelial cells were transfected with short interfering RNA against the p47(phox) subunit of NADPH oxidase, treated in the absence or presence of VEGF, and assayed for signaling, gene expression, and function. We show that NADPH oxidase activity is required for VEGF activation of phosphoinositide 3-kinase-Akt-forkhead, and p38 MAPK, but not ERK1/2 or JNK. The permissive role of NADPH oxidase on phosphoinositide 3-kinase-Akt-forkhead signaling is mediated at post-VEGF receptor levels and involves the nonreceptor tyrosine kinase Src. DNA microarrays revealed the existence of two distinct classes of VEGF-responsive genes, one that is ROS-dependent and another that is independent of ROS levels. VEGF-induced, thrombomodulin-dependent activation of protein C was dependent on NADPH oxidase activity, whereas VEGF-induced decay-accelerating factor-mediated protection of endothelial cells against complement-mediated lysis was not. Taken together, these findings suggest that NADPH oxidase-derived ROS selectively modulate some but not all the effects of VEGF on endothelial cell phenotypes.

Vascular calcification is a common complication in atherosclerosis. Bone morphogenetic protein-2 (BMP-2) plays an important role in atherosclerotic vascular calcification. The aim of this study was to determine the effect of oxidized low density lipoprotein (oxLDL) on BMP-2 protein expression in human coronary artery endothelial cells (CAECs), the roles of Toll-like receptor (TLR) 2 and TLR4 in oxLDL-induced BMP-2 expression, and the signaling pathways involved. Human CAECs were stimulated with oxLDL. The roles of TLR2 and TLR4 in oxLDL-induced BMP-2 expression were determined by pretreatment with neutralizing antibody, siRNA, and overexpression. Stimulation with oxLDL increased cellular BMP-2 protein levels in a dose-dependent manner (40-160 μg/ml). Pretreatment with neutralizing antibodies against TLR2 and TLR4 or silencing of these two receptors reduced oxLDL-induced BMP-2 expression. Overexpression of TLR2 and TLR4 enhanced the cellular BMP-2 response to oxLDL. Furthermore, oxLDL was co-localized with TLR2 and TLR4. BMP-2 expression was associated with activation of nuclear factor-κB (NF-κB), p38 mitogen-activated protein kinase (MAPK), and extracellular signal-regulated kinase (ERK)1/2. Inhibition of NF-κB and ERK1/2 reduced BMP-2 expression whereas inhibition of p38 MAPK had no effect. In conclusion, oxLDL induces BMP-2 expression through TLR2 and TLR4 in human CAECs. The NF-κB and ERK1/2 pathways are involved in the signaling mechanism. These findings underscore an important role for TLR2 and TLR4 in mediating the BMP-2 response to oxLDL in human CAECs and indicate that these two immunoreceptors contribute to the mechanisms underlying atherosclerotic vascular calcification.

The expression of cannabinoid receptor 1 is significantly increased in atopic patients

Recently, we have shown that transient phosphorylation and inhibition of the pro-apoptotic transcription factor, forkhead, by vascular endothelial growth factor (VEGF) is essential for endothelial cell (EC) survival and proliferation. The goal of the present study was to determine whether forkhead (FKHR) also plays a positive role in agonist-mediated gene induction. Human coronary artery ECs were transduced with adenovirus overexpressing constitutively active phosphorylation-resistant triple mutant FKHR or transfected with small interference RNA (siRNA) against FKHR. The cells were then treated in the absence or presence of VEGF and assayed for gene expression using quantitative real-time PCR and Northern blots analyses. The data revealed a novel set of VEGF-responsive genes that require FKHR activity for optimal expression in ECs, including bone morphogenic protein 2, cbp/p300-interacting transactivator 2, decay accelerating factor (DAF), vascular cell adhesion molecule-1 (VCAM-1), manganese superoxide dismutase, endothelial-specific molecule-1, RING1 and YY1-binding protein, and matrix metalloproteinase-10. Consistent with a positive role for FKHR in mediating VEGF induction of DAF and VCAM-1 mRNA, siRNA against FKHR attenuated the effect of VEGF on complement-mediated EC lysis and monocyte adhesion, respectively. VEGF induction of the forkhead-dependent genes was down-regulated by the NF-kappaB inhibitor, constitutively active Ad-IkappaB, and in some cases by the nuclear factor of activated T-cells (NF-AT) inhibitor, cyclosporin. Together, these findings suggest that the VEGF-forkhead signaling axis plays an important functional role in ECs beyond the regulation of cell survival/apoptosis and cell cycle.

Quality of Life and Depression in CKD: Improving Hope and Health

Association of Catalytic Iron With Cardiovascular Disease

Oncogenes can alter metabolism by changing the balance between anabolic and catabolic processes. However, how oncogenes regulate tumor cell biomass remains poorly understood. Using isogenic MCF10A cells transformed with nine different oncogenes, we show that specific oncogenes reduce the biomass of cancer cells by promoting extracellular vesicle (EV) release. While MYC and AURKB elicited the highest number of EVs, each oncogene selectively altered the protein composition of released EVs. Likewise, oncogenes alter secreted miRNAs. MYC-overexpressing cells require ceramide, whereas AURKB requires ESCRT to release high levels of EVs. We identify an inverse relationship between MYC upregulation and activation of the RAS/MEK/ERK signaling pathway for regulating EV release in some tumor cells. Finally, lysosome genes and activity are downregulated in the context of MYC and AURKB, suggesting that cellular contents, instead of being degraded, were released via EVs. Thus, oncogene-mediated biomass regulation via differential EV release is a new metabolic phenotype.

Neuropilin-1 (NP-1) is a receptor for vascular endothelial growth factor-A165 (VEGF-A165) in endothelial cells. To define the role of NP-1 in the biological functions of VEGF, we developed a specific peptide antagonist of VEGF binding to NP-1 based on the NP-1 binding site located in the exon 7- and 8-encoded VEGF-A165 domain. The bicyclic peptide, EG3287, potently (K(i) 1.2 microM) and effectively (>95% inhibition at 100 microM) inhibited VEGF-A165 binding to porcine aortic endothelial cells expressing NP-1 (PAE/NP-1) and breast carcinoma cells expressing only NP-1 receptors for VEGF-A, but had no effect on binding to PAE/KDR or PAE/Flt-1. Molecular dynamics calculations, a nuclear magnetic resonance structure of EG3287, and determination of stability in media, indicated that it constitutes a stable subdomain very similar to the corresponding region of native VEGF-A165. The C terminus encoded by exon 8 and the three-dimensional structure were both critical for EG3287 inhibition of NP-1 binding, whereas modifications at the N terminus had little effect. Although EG3287 had no direct effect on VEGF-A165 binding to KDR receptors, it inhibited cross-linking of VEGF-A165 to KDR in human umbilical vein endothelial cells co-expressing NP-1, and inhibited stimulation of KDR and PLC-gamma tyrosine phosphorylation, activation of ERKs1/2 and prostanoid production. These findings characterize the first specific antagonist of VEGF-A165 binding to NP-1 and demonstrate that NP-1 is essential for optimum KDR activation and intracellular signaling. The results also identify a key role for the C-terminal exon 8 domain in VEGF-A165 binding to NP-1.

Ranibizumab Is a Potential Prophylaxis for Proliferative Vitreoretinopathy, a Nonangiogenic Blinding Disease