Single-Cell Transcriptomics and Fate Mapping of Ependymal Cells Reveals an Absence of Neural Stem Cell Function.

Ependymal cells are multi-ciliated cells that form the brain's ventricular epithelium and a niche for neural stem cells (NSCs) in the ventricular-subventricular zone (V-SVZ). In addition, ependymal cells are suggested to be latent NSCs with a capacity to acquire neurogenic function. This remains highly controversial due to a lack of prospective in vivo labeling techniques that can effectively distinguish ependymal cells from neighboring V-SVZ NSCs. We describe a transgenic system that allows for targeted labeling of ependymal cells within the V-SVZ. Single-cell RNA-seq revealed that ependymal cells are enriched for cilia-related genes and share several stem-cell-associated genes with neural stem or progenitors. Under in vivo and in vitro neural-stem- or progenitor-stimulating environments, ependymal cells failed to demonstrate any suggestion of latent neural-stem-cell function. These findings suggest remarkable stability of ependymal cell function and provide fundamental insights into the molecular signature of the V-SVZ niche.

Evidence for Pro-angiogenic Functions of VEGF-Ax.

The VEGF-A isoforms play a crucial role in vascular development, and the VEGF signaling pathway is a clinically validated therapeutic target for several pathological conditions. Alternative mRNA splicing leads to the generation of multiple VEGF-A isoforms, including VEGF165. A recent study reported the presence of another isoform, VEGF-Ax, arising from programmed readthrough translation. Compared to VEGF165, VEGF-Ax has a 22-amino-acid extension in the COOH terminus and has been reported to function as a negative regulator of VEGF signaling in endothelial cells, with potent anti-angiogenic effects. Here, we show that, contrary to the earlier report, VEGF-Ax stimulates endothelial cell mitogenesis, angiogenesis, as well as vascular permeability. Accordingly, VEGF-Ax induces phosphorylation of key tyrosine residues in VEGFR-2. Notably, VEGF-Ax was less potent than VEGF165, consistent with its impaired binding to the VEGF co-receptor neuropilin-1.

VEGF is an essential retrograde trophic factor for motoneurons.

VEGF was initially discovered due to its angiogenic activity and therefore named "vascular endothelial growth factor." However, its more recently discovered neurotrophic activity may be evolutionarily more ancient. Our previous work showed that all the changes produced by axotomy on the firing activity and synaptic inputs of abducens motoneurons were completely restored after VEGF administration. Therefore, we hypothesized that the lack of VEGF delivered by retrograde transport from the periphery should also affect the physiology of otherwise intact abducens motoneurons. For VEGF retrograde blockade, we chronically applied a neutralizing VEGF antibody to the lateral rectus muscle. Recordings of extracellular single-unit activity and eye movements were made in alert cats before and after the application of the neutralizing antibody. Our data revealed that intact, noninjured abducens motoneurons retrogradely deprived of VEGF exhibited noticeable changes in their firing pattern. There is a general decrease in firing rate and a significant reduction in eye position and eye velocity sensitivity (i.e., a decrease in the tonic and phasic components of their discharge, respectively). Moreover, by means of confocal immunocytochemistry, motoneurons under VEGF blockade showed a marked reduction in the density of afferent synaptic terminals contacting with their cell bodies. Altogether, the present findings demonstrate that the lack of retrogradely delivered VEGF renders abducens motoneurons into an axotomy-like state. This indicates that VEGF is an essential retrograde factor for motoneuronal synaptic drive and discharge activity.

Current advances in nanoformulations of therapeutic agents targeting tumor microenvironment to overcome drug resistance.

The tumor microenvironment (TME) plays a pivotal role in cancer development and progression. In this line, revealing the precise mechanisms of the TME and associated signaling pathways of tumor resistance could pave the road for cancer prevention and efficient treatment. The use of nanomedicine could be a step forward in overcoming the barriers in tumor-targeted therapy. Novel delivery systems benefit from enhanced permeability and retention effect, decreasing tumor resistance, reducing tumor hypoxia, and targeting tumor-associated factors, including immune cells, endothelial cells, and fibroblasts. Emerging evidence also indicates the engagement of multiple dysregulated mediators in the TME, such as matrix metalloproteinase, vascular endothelial growth factor, cytokines/chemokines, Wnt/ß-catenin, Notch, Hedgehog, and related inflammatory and apoptotic pathways. Hence, investigating novel multitargeted agents using a novel delivery system could be a promising strategy for regulating TME and drug resistance. In recent years, small molecules from natural sources have shown favorable anticancer responses by targeting TME components. Nanoformulations of natural compounds are promising therapeutic agents in simultaneously targeting multiple dysregulated factors and mediators of TME, reducing tumor resistance mechanisms, overcoming interstitial fluid pressure and pericyte coverage, and involvement of basement membrane. The novel nanoformulations employ a vascular normalization strategy, stromal/matrix normalization, and stress alleviation mechanisms to exert higher efficacy and lower side effects. Accordingly, the nanoformulations of anticancer monoclonal antibodies and conventional chemotherapeutic agents also improved their efficacy and lessened the pharmacokinetic limitations. Additionally, the coadministration of nanoformulations of natural compounds along with conventional chemotherapeutic agents, monoclonal antibodies, and nanomedicine-based radiotherapy exhibits encouraging results. This critical review evaluates the current body of knowledge in targeting TME components by nanoformulation-based delivery systems of natural small molecules, monoclonal antibodies, conventional chemotherapeutic agents, and combination therapies in both preclinical and clinical settings. Current challenges, pitfalls, limitations, and future perspectives are also discussed.

Generation and characterisation of scalable and stable human pluripotent stem cell-derived microvascular-like endothelial cells for cardiac applications.

Coronary microvascular disease (CMD) and its progression towards major adverse coronary events pose a significant health challenge. Accurate in vitro investigation of CMD requires a robust cell model that faithfully represents the cells within the cardiac microvasculature. Human pluripotent stem cell-derived endothelial cells (hPSC-ECs) offer great potential; however, they are traditionally derived via differentiation protocols that are not readily scalable and are not specified towards the microvasculature. Here, we report the development and comprehensive characterisation of a scalable 3D protocol enabling the generation of phenotypically stable cardiac hPSC-microvascular-like ECs (hPSC-CMVECs) and cardiac pericyte-like cells. These were derived by growing vascular organoids within 3D stirred tank bioreactors and subjecting the emerging 3D hPSC-ECs to high-concentration VEGF-A treatment (3DV). Not only did this promote phenotypic stability of the 3DV hPSC-ECs; single cell-RNA sequencing (scRNA-seq) revealed the pronounced expression of cardiac endothelial- and microvascular-associated genes. Further, the generated mural cells attained from the vascular organoid exhibited markers characteristic of cardiac pericytes. Thus, we present a suitable cell model for investigating the cardiac microvasculature as well as the endothelial-dependent and -independent mechanisms of CMD. Moreover, owing to their phenotypic stability, cardiac specificity, and high angiogenic potential, the cells described within would also be well suited for cardiac tissue engineering applications.

The 3D organ-on-a-chip model unveils a dual role of GDF-15 in vascular growth.

Pathological conditions such as oxidative stress or inflammation may alter the homeostasis of adventitia triggering vascular wall remodeling and abnormal angiogenesis, what can lead to development of atherosclerosis. Growth differentiation factor-15 (GDF-15) is a stress-responsive cytokine and metabolic regulator, but its role in angiogenesis is not yet fully defined. Here we utilized an organ-on-a-chip technology to analyze endothelial sprouting in an adventitia-resembling microenvironment. We analyzed angiogenic responses to growth factor gradient across the extracellular matrix-resembling fibrin gel and in cell co-culture in response to GDF-15-treated adventitial fibroblasts. We observed that GDF-15 enhanced the pro-angiogenic effect of vascular endothelial growth factor. On the other hand, GDF-15-treated adventitial fibroblasts decreased endothelial sprouting. GDF-15 seems to indirectly affect endothelial cells and, depending on the microenvironment, its effect can be either pro- or anti-angiogenic.

The Intracellular Interaction of Porcine ß-Defensin 2 with VASH1 Alleviates Inflammation via Akt Signaling Pathway.

Defensins are a major class of antimicrobial peptides that facilitate the immune system to resist pathogen infection. To date, only ß-defensins have been identified in pigs. In our previous studies, porcine ß-defensin 2 (PBD-2) was shown to have both bactericidal activity and modulatory roles on inflammation. PBD-2 can interact with the cell surface TLR4 and interfere with the NF-κB signaling pathway to suppress the inflammatory response. In this study, the intracellular functions of PBD-2 were investigated. The fluorescently labeled PBD-2 could actively enter mouse macrophage cells. Proteomic analysis indicated that 37 proteins potentially interacted with PBD-2, among which vasohibin-1 (VASH1) was further tested. LPS, an inflammation inducer, suppressed the expression of VASH1, whereas PBD-2 inhibited this effect. PBD-2 inhibited LPS-induced activation of Akt, expression and release of the inflammatory mediators vascular endothelial growth factor and NO, and cell damage. A follow-up VASH1 knockdown assay validated the specificity of the above observations. In addition, PBD-2 inhibited LPS-induced NF-κB activation via Akt. The inhibition effects of PBD-2 on LPS triggered suppression of VASH1 and activation of Akt, and NF-κB and inflammatory cytokines were also confirmed using pig alveolar macrophage 3D4/21 cells. Therefore, the data indicate that PBD-2 interacts with intracellular VASH1, which inhibits the LPS-induced Akt/NF-κB signaling pathway, resulting in suppression of inflammatory responses. Together with our previous findings, we conclude that PBD-2 interacts with both the cell surface receptor (TLR4) and also with the intracellular receptor (VASH1) to control inflammation, thereby providing insights into the immunomodulatory roles of defensins.

Phosphatidylserine accelerates wound healing and reduces necrosis in the rats: Growth factor activation.

To examine the effect of topical phosphatidylserine (PS) on wound healing factors and tissue necrosis in in vivo models. Topical PS was applied to evaluate aspects of the wound healing process and growth factors production of vascular endothelial growth factors (VEGF) as well a necrosis reduction in the skin flap of rat models. Moreover, phenytoin (PHT) and cyclosporine A (CsA) were used topically as positive control treatments in wound and necrosis models, respectively. Immunohistochemistry (IHC) VEGF, transforming growth factor-ß (TGF-ß), fibroblast growth factor (FGF) and histopathology were analysed on the wounds of rats. In the necrosis assessment, necrotic areas were determined on photography taken from the back skin of rats. Results indicated that PS topically enhanced significantly (P < 0.05) numbers of fibroblasts and endothelium while inhibiting the neutrophils and macrophages during the 14 days of wound treatment. Moreover, higher values of collagen deposition and epithelialization scores as well as wound recovery percentage (near 80%) were determined significantly (P < 0.05) in the PS group compared with the control. IHC analysis determined that FGF and VEGF cytokine factors were elevated in the wound site by topical PS. Moreover, the necrotic area was significantly (P < 0.05) improved in the PS group. Our experiment indicated that wound improvement and flap survival values in PS treatments were superior to PHT and CsA control groups, respectively. In conclusion, these findings suggest the potential of PS application in the healing of wounds and control of necrosis development after surgery or skin injuries.

VEGF-A-induced changes in distal outflow tract structure and function.

PURPOSE: To investigate changes in distal outflow tract vessels caused by VEGF-A and their impact on outflow. METHODS: We compared VEGF-A perfused porcine anterior segments with and without trabecular meshwork (TM) to control eyes. In the first experiment (n=48), we analyzed live changes of the outflow tract with spectral-domain optical coherence tomography (SD-OCT) over 3 h and reconstructed them in 3D. In a second experiment (n=32), we measured the intraocular pressure (IOP) variation in response to VEGF-A over 48 h and computed the outflow facility. RESULTS: VEGF-A increased the vessel volume of the distal outflow tract by 16.8±10.6% while control eyes remained unchanged (0.5±6.8%). Volume changes occurred within the first 100 min before plateauing at 140 min. VEGF-A enhanced the outflow facility in eyes without TM by 38.6±25.5% at 24 h as compared to controls (p<0.05). CONCLUSION: VEGF-A dilated vessels of the distal outflow tract and increased the outflow facility even after TM removal, pointing to a regulatory mechanism independent of proximal structures.

Satellite glial cell-secreted exosomes after in-vitro oxaliplatin treatment presents a pro-nociceptive effect for dorsal root ganglion neurons and induce mechanical hypersensitivity in naïve mice.

BACKGROUND: The pathophysiological mechanism underlying chemotherapy-induced neuropathic pain (CINP) remains unclear. Sensory neuronal hypersensitivity in the dorsal root ganglion (DRG) is essential for the onset and maintenance of chronic pain. Satellite glial cells (SGCs) in the DRG potentially affect the function of sensory neurons, possibly by mediating extracellular or paracrine signaling. Exosomes play an essential role in cell-cell communication. However, the role of SGC-secreted exosomes in glia-neuron communication and CINP remains unclear. METHODS: SGCs and sensory neurons were cultured from the DRG of mice. The SGCs were treated with 4 µM oxaliplatin for 24 h. Glial fibrillary acid protein (GFAP) and connexin-43 (Cx-43) expressions in the SGCs were examined with immunocytochemistry (ICC). Enzyme-linked immunosorbent assay (ELISA) detected cytokine release in the SGCs after oxaliplatin treatment. Subsequently, SGC-secreted exosomes were collected using ultracentrifugation and identified by nanoparticle tracking analysis, transmission electron microscopy, and western blotting. Subsequently, DRG neurons were incubated with SGC-secreted exosomes for 24 h. The percentage of reactive oxygen species (ROS)-positive neurons was detected using flow cytometry, and acid-sensing ion channel 3 (ASIC3) and transient receptor potential vanilloid 1 (TRPV1) expression were examined by western blotting. SGC-secreted exosomes were intrathecally injected into naïve mice. The mechanical withdrawal threshold was assessed 24, 48, and 72 h following the injection. TRPV1 expression in the DRG was examined 72 h after intrathecal injection. Furthermore, differentially expressed (DE) miRNAs within the SGC-secreted exosomes were detected using RNA sequencing and bioinformatics analysis. Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Reactome pathway analyses were performed to predict the function of the target genes of DE miRNAs. Finally, the DE miRNAs with pain regulation potential were identified in silico. RESULTS: After in-vitro oxaliplatin treatment, ICC showed an increase in the immunoreactivity of GFAP and Cx-43 in the SGCs. ELISA results suggested an increased release of tumor necrosis factor-α and interleukin (IL)-1ß, but a decreased release of IL-10. Oxaliplatin treatment increased the secretion of exosomes in the SGCs from 4.34 to 5.99 × 1011 (particles/ml). The exosome-specific markers CD9 and TSG101 were positive, whereas calnexin was negative for the obtained exosomes. Additionally, the SGC-secreted exosomes were endocytosed by DRG neurons after co-incubation. Moreover, after incubation with conditioned SGC-secreted exosomes (after 4 µM oxaliplatin treatment), the percentage of ROS-positive DRG neurons increased and ASIC3 and TRPV1 expressions were upregulated. After the intrathecal injection of the conditioned SGC-secreted exosomes, the mice presented with mechanical hypersensitivity and TRPV1 expression upregulation in the DRG. Notably, 25 and 120 significantly upregulated and downregulated miRNAs, respectively, were identified in the conditioned SGC-secreted exosomes. When predicting the function of target genes of DE miRNAs, certain GO terms, such as synapse organization, neurogenesis regulation, histone modification, and pain-related KEGG or Reactome pathways, including vascular endothelial growth factor A-vascular endothelial growth factor receptor 2, mammalian target of rapamycin, and mitogen-activated protein kinase signaling pathways, related to nervous system function were predicted. Finally, 27 pain regulation-related miRNAs, including miR-324-3p, miR-181a-5p, and miR-122-5p, were identified in silico. CONCLUSION: Our study demonstrates that SGC-secreted exosomes after in-vitro oxaliplatin treatment present a pro-nociceptive effect for DRG neurons and induce mechanical hypersensitivity in naïve mice, possibly via the contained miRNA cargo. Identifying the candidate miRNAs and verifying their functions in vivo are required to elucidate the exosomes mediating 'glia-neuron' communication under CINP condition.

New Indole-6-Carboxylic Acid Derivatives as Multi-Target Antiproliferative Agents: Synthesis, in Silico Studies, and Cytotoxicity Evaluation.

Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor (VEGFR) are commonly overexpressed in cancers making them appealing targets for cancer therapeutics. Two groups of indole-6-carboxylic acid derivatives, hydrazone derivatives targeting EGFR and oxadiazole derivatives targeting VEGFR-2, were synthesized and characterized using FT-IR, 1 H-NMR, 13 CNMR, and HR-MS techniques. Binding patterns to potential molecular targets were studied using molecular docking and compared to standard EGFR and VEGFR-2 inhibitors. The newly synthesized compounds were cytotoxic to the three cancer cell lines tested (HCT-116, HeLa, and HT-29 cell lines) as evaluated by the MTT assay. Compound 3 b (EGFR-targeting) and compound 6 e (VEGFR-2-targeting) possessed the highest antiproliferation activity, were cancer-selective, arrested cancer cells in the G2/M phase, induced the extrinsic apoptosis pathway, and had the highest EGFR/VEGFR-2 enzyme inhibitory activity, respectively. The structure-activity relationships of the new compounds showed that the presence of an aryl or heteroaryl fragment attached to a linker is required for the anti-tumor activity. In conclusion, the findings of the current study suggest that compounds 3 b and 6 e are promising cytotoxic agents that act by inhibiting EGFR and VEGFR-2 tyrosine kinases, respectively.

Development of Novel Indazolyl-Acyl Hydrazones as Antioxidant and Anticancer Agents that Target VEGFR-2 in Human Breast Cancer Cells.

The increased expression of VEGFR-2 in a variety of cancer cells promotes a cascade of cellular responses that improve cell survival, growth, and proliferation. Heterocycles are common structural elements in medicinal chemistry and commercially available medications that target several biological pathways and induce cell death in cancer cells. Herein, the evaluation of indazolyl-acyl hydrazones as antioxidant and anticancer agents is reported. Compounds 4e and 4j showed inhibitory activity in free radical scavenging assays (DPPH and FRPA). The titled compounds were employed in cell viability studies using MCF-7 cells, and it was observed that compounds 4f and 4j exhibited IC50 values 15.83 µM and 5.72 µM, respectively. In silico docking revealed the favorable binding energies of -7.30 kcal/mol and -8.04 kcal/mol for these compounds towards Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2), respectively. In conclusion, compounds with antioxidant activity and that target VEGFR-2 in breast cancer cells are reported.

Investigating the Promising Anticancer Activity of Cetuximab and Fenbendazole Combination as Dual CBS and VEGFR-2 Inhibitors and Endowed with Apoptotic Potential.

In this work, the cytotoxicity of monoclonal antibody (Cetuximab, Ce) and Fenbendazole (Fen), as well as their combination therapy were tested with the MTT assay. On the other side, Ce, Fen, and a combination between them were subjected to a colchicine-tubulin binding test, which was conducted and compared to Colchicine as a reference standard. Besides, Ce, Fen, and the combination of them were tested against the VEGFR-2 target receptor, compared to Sorafenib as the standard medication. Moreover, the qRT-PCR technique was used to investigate the levels of apoptotic genes (p53 and Bax) and anti-apoptotic gene (Bcl-2) as well. Also, the effect of Ce, Fen, and the combination of them on the level of ROS was studied. Furthermore, the cell cycle analysis and Annexin V apoptosis assay were carried out for Ce, Fen, and a combination of them. In addition, the molecular docking studies were used to describe the molecular levels of interactions for both (Fen and colchicine) or (Fen and sorafenib) within the binding pockets of the colchicine binding site (CBS) and vascular endothelial growth factor-2 receptor (VEGFR-2), respectively.

ER-ß accelerates the process of primary osteoporosis by promoting VEGFA-mediated apoptosis of osteoblasts.

Primary osteoporosis (POP) is a widespread and severe disorder of bone metabolism characterized by reduced bone mass and destruction of bone structure, frequently inducing fracture risk and imposing a heavy economic burden on public life. The development of POP partially revolves around the estrogen receptor ß (ER-ß), one of the major mediator receptors of estrogen that influences apoptosis in a range of cells. We performed KEGG and GO analysis by mining the transcriptomic dataset of POP samples showing significant enrichment of differentially expressed genes (DEGs) in multiple apoptosis-related pathways. The results of the Spearman correlation analysis and Protein-Protein Interaction (PPI) Networks screening of hub genes indicated that vascular endothelial growth factor A (VEGFA) may be a key target of ER-ß in controlling osteoblast apoptosis. Further, we carried out high-throughput sequencing of ESR2-silenced MC3T3-E1 cells and noticed a substantial suppression in VEGFA expression and all apoptosis-related pathways. In addition, we determined the cell cycle and apoptosis by constructing a VEGFA-silenced cell model utilizing flow cytometry (FCM), and the results showed that ER-ß could regulate the osteoblast cycle and thus promote osteoblast apoptosis by promoting VEGFA expression. And Western blot results showed that apoptosis was most likely realized through the regulation of downstream apoptosis markers c-JUN (c-Jun N-terminal kinase, JNK) and GADD45G (Growth Arrest and DNA Damage-Inducible Protein 45 gamma). The effects of ESR2 and VEGFA on the proliferation of osteoblasts were lastly assessed using the cell counting kit- 8 (CCK-8) assay. In conclusion, this study identifies that the roles of ER-ß in the regulation of osteoblast apoptosis are closely related to VEGFA and provides a new target for POP treatment.

Benzothiazole-based apoptosis inducers: A comprehensive overview and future prospective.

Cancer has become a major concern in healthcare globally, and over time, incidences and prevalence of cancer are increasing. To counter this, a lot of anticancer drugs are approved and are in clinical use, playing a pivotal role in its treatment. Due to drug resistance and adverse effects, a continuous demand for novel, potent, and safe candidates to treat cancer is always there. Over the last few decades, various heterocyclic ring-based derivatives have been explored and reported in the literature. In this regard, benzothiazole scaffold-based compound emerged as the versatile ring for developing novel and safe anticancer candidates. In this article, we have reported various benzothiazole heterocyclic ring-based derivatives demonstrating potent antiproliferative activity by induction of apoptosis via an intrinsic pathway in a dose-dependent manner. These compounds also displayed inhibition of different enzymes, for example, Aurora kinase, epidermal growth factor receptor, vascular endothelial growth factor receptor, phosphoinositide kinases, DNA topoisomerase, and tubulin polymerases. This study focused on a comprehensive overview of antiproliferative activity, structure-activity relationship, apoptosis induction activity, and enzyme inhibition by benzothiazole-based compounds.

Exploration of antiproliferative potential of modified triazole-benzohydrazone scaffold: Multitarget approach.

A novel series of triazole-benzohydrazone hybrids was efficiently designed and synthesized as antiproliferative agents, targeting different kinases. All compounds were screened via the National Cancer Institute (NCI) against 60 cancer cell lines, where compounds 16, 17, and 18 exhibited growth inhibition percent (GI%) of various leukemia subpanels with values of 70.33%, 64.13%, and 76.03%, respectively. Compound 18 showed broad-spectrum antiproliferative efficacy toward most cancer cells, with outstanding potency regarding melanoma (MALME-3M GI% = 101.82%) and breast cancer cell lines (MCF7 GI% = 85.87%), while proving safe toward the WI-38 normal cell line, compared to doxorubicin. Multikinase investigation including vascular endothelial growth factor receptor 2 (VEGFR-2), mesenchymal epithelial transition factor (c-Met), proto-oncogene B-Raf, mitogen-activated protein kinase kinase, extracellular signal-regulated kinase, and phosphoinositide 3-kinase was accomplished to reveal its plausible mechanism of action, giving the ultimate potency against both VEGFR-2 and c-Met with IC50 values of 0.055 and 0.042 µM, respectively, while displaying moderate to good inhibition concerning the remaining kinases. DNA binding capability was excluded using the methyl green colorimetric assay. Further, it exhibited both early and late apoptotic induction by about 16- and 9.4-fold over the control, respectively, triggering cell cycle arrest in the G2/M phase. Physicochemical properties and bioavailability radar plot inferred drug-likeness characteristics for compound 18. The molecular docking study assessed the binding pattern with the active sites of c-Met and VEGFR-2.

Equine Endothelial Cells Show Pro-Angiogenic Behaviours in Response to Fibroblast Growth Factor 2 but Not Vascular Endothelial Growth Factor A.

Understanding the factors which control endothelial cell (EC) function and angiogenesis is crucial for developing the horse as a disease model, but equine ECs remain poorly studied. In this study, we have optimised methods for the isolation and culture of equine aortic endothelial cells (EAoECs) and characterised their angiogenic functions in vitro. Mechanical dissociation, followed by magnetic purification using an anti-VE-cadherin antibody, resulted in EC-enriched cultures suitable for further study. Fibroblast growth factor 2 (FGF2) increased the EAoEC proliferation rate and stimulated scratch wound closure and tube formation by EAoECs on the extracellular matrix. Pharmacological inhibitors of FGF receptor 1 (FGFR1) (SU5402) or mitogen-activated protein kinase (MEK) (PD184352) blocked FGF2-induced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and functional responses, suggesting that these are dependent on FGFR1/MEK-ERK signalling. In marked contrast, vascular endothelial growth factor-A (VEGF-A) had no effect on EAoEC proliferation, migration, or tubulogenesis and did not promote ERK1/2 phosphorylation, indicating a lack of sensitivity to this classical pro-angiogenic growth factor. Gene expression analysis showed that unlike human ECs, FGFR1 is expressed by EAoECs at a much higher level than both VEGF receptor (VEGFR)1 and VEGFR2. These results suggest a predominant role for FGF2 versus VEGF-A in controlling the angiogenic functions of equine ECs. Collectively, our novel data provide a sound basis for studying angiogenic processes in horses and lay the foundations for comparative studies of EC biology in horses versus humans.

Quercetin can be a more reliable treatment for metastatic prostate cancer than the localized disease: An in vitro study.

Quercetin is a plant flavonoid that has been recognized to have anti-inflammatory, antioxidant and anti-proliferative activities. This study aims to evaluate the inhibitory effects of quercetin against prostate malignancy in vitro and the underlying resistance mechanism. IC50 values of quercetin were determined by MTT assay. Annexin-V/PI staining was used to measure the rate of apoptosis. DNA cell cycle was analysed by PI staining method. Real-time PCR was performed to assess mRNA levels of OPN isoforms, VEGF isoforms, P53 and KLK2. Migration potential, proliferative capability and nucleus morphology of cells were evaluated by the scratch-wound assay, colony-forming assay and Hoechst staining, respectively. Quercetin significantly increased the apoptosis rate of PC-3 and LNCaP cell lines, arrested the cell cycle at the sub-G1/G1 phase, and reduced the migration potential and colony-forming capability. Moreover, upregulation of apoptosis-related genes and downregulation of genes involved in proliferation and angiogenesis was also observed. Although our results elucidated that quercetin has antitumor effects on PC-3 and LNCaP, for the first time, we showed that quercetin treatment causes alterations in the expression of OPN and VEGF isoforms, which are cancer-promoting modulators through various processes such as angiogenesis and drug-resistance. Prostate malignant cells can dodge the anti-carcinogenic properties of quercetin via modulation of OPN and VEGF isoforms in vitro. Therefore, quercetin acts as a double-edged sword in prostate cancer treatment.

Myocardial angiogenesis induced by concurrent vitamin D supplementation and aerobic-resistance training is mediated by inhibiting miRNA-15a, and miRNA-146a and upregulating VEGF/PI3K/eNOS signaling pathway.

This study aimed to investigate the effects of co-treatment of aerobic-resistance training (ART), vitamin D3 (VD3) on cardiovascular function considering the involvement of microRNA-15a and microRNA-146a, vascular endothelial growth factor (VEGF), phosphatidylinositol-3 kinase (PI3K), and endothelial nitric oxide synthase (eNOS) after myocardial infarction (MI) in rats. To induce MI, male Wistar rats subcutaneously received isoproterenol for 2 days, then MI was confirmed by echocardiography. MI rats were divided into six groups (n = 8/group). MI + VD3, MI + sesame oil (Veh), MI + ART, MI + VD3 + ART, and MI + Veh + ART, and received the related treatments for 8 weeks. Exercise tests, echocardiography, real-time quantitative polymerase chain reaction (qRT-PCR), western blotting, and histological staining were performed after the end of treatments. The highest ejection fraction (EF%), fractional shortening (FS%), exercise capacity (EC), and maximal load test (MLT) amounts were observed in the groups treated with VD3, ART, and VD3 + ART (P < 0.05). These were accompanied by a significantly increased angiogenesis post-MI. Furthermore, the levels of circulating microRNA-15a and microRNA-146a were significantly decreased in these groups compared to MI rats that were together with a significant upregulation of cardiac VEGF, PI3K, and eNOS expression. Overall, the best results were observed in the group treated with VD3 + ART. Concurrent VD3 supplementation and ART attenuated microRNA-15a and microRNA-146a and induced angiogenesis via VEGF/PI3K/eNOS axis. This data demonstrate that concurrent VD3 supplementation and ART is a more efficient strategy than monotherapy to improve cardiac function post-MI.

Variations in mechanical stiffness alter microvascular sprouting and stability in a PEG hydrogel model of idiopathic pulmonary fibrosis.

OBJECTIVE: Microvascular remodeling is governed by biomechanical and biochemical cues which are dysregulated in idiopathic pulmonary fibrosis. Understanding how these cues impact endothelial cell-pericyte interactions necessitates a model system in which both variables can be independently and reproducibly modulated. In this study we develop a tunable hydrogel-based angiogenesis assay to study how varying angiogenic growth factors and environmental stiffness affect sprouting and vessel organization. METHODS: Lungs harvested from mice were cut into 1 mm long segments then cultured on hydrogels having one of seven possible stiffness and growth factor combinations. Time course, brightfield, and immunofluorescence imaging were used to observe and quantify sprout formation. RESULTS: Our assay was able to support angiogenesis in a comparable manner to Matrigel in soft 2 kPa gels while enabling tunability to study the effects of stiffness on sprout formation. Matrigel and 2 kPa groups contained significantly more samples with sprouts when compared to the stiffer 10 and 20 kPa gels. Growth factor treatment did not have as obvious an effect, although the 20 kPa PDGF + FGF-treated group had significantly longer vessels than the vascular endothelial growth factor-treated group. CONCLUSIONS: We have developed a novel, tunable hydrogel assay for the creation of lung explant vessel organoids which can be modulated to study the impact of specific environmental cues on vessel formation and maturation.