Vascular Endothelial Growth Factor Signaling Research Articles

Abstract 5968: Ethnodyne Visio™ affects EGFR signaling in breast cancer

Abstract Breast Cancer (BC), the most common form of female cancer, is one of the most extensively studied diseases. Metastasis is the process by which a cancer cell travels to another part of the body and starts to multiply. This detrimental occurrence is one of the primary forms of disease relapse in cancer patients and accounts for an estimated 90 percent of cancer deaths. Ethnodyne Visio™ is a new drug for Age-Related Macular Degeneration (AMD), the primary cause for blindness in people 65 and older. It is a mixture of phytochemicals Withaferin A, Gallic Acid, and Bacopaside I. However, the exact mechanism of action of Ethnodyne Visio™ is not known. Macular Degeneration occurs in two primary forms: wet and dry. Wet Macular Degeneration shows surprising similarities with metastatic Breast Cancer in terms of their progression and causation. As both diseases evolve, the retina (in the case of Wet AMD) and the tumor (in the case of BC) secrete Vascular Endothelial Growth Factor (VEGF) to encourage vascular development. In Wet AMD, this new and unregulated vascular growth, or angiogenesis, causes “leaky” blood vessels that allow fluid to enter the retina, ultimately causing blindness. In BC, this blood vessel growth provides a means for the tumor to obtain nutrients as well as disseminate metastatic cells. We determined if there exists any easily accessible nutraceuticals possessing effective antiangiogenic properties. We used CAMs (chick chorioallantoic membrane), grown ex-ovo, to study angiogenesis. We found that Ashwagandha (Withaferin A) blocked angiogenesis of CAMs by 67%. Taking clues from these observations, we wanted to determine possible molecular signaling mechanisms triggered by Ethnodyne Visio™ that may counter progression of BC. We hypothesized that Ethnodyne Visio™ may have anti-angiogenic properties. Using multiple online gene association platforms, we compiled a list of transcriptomic changes caused by Withaferin A, Gallic Acid, and Bacopaside I on breast tumor cells. A g:Profiler analysis of the combined transcriptomic changes revealed Epidermal Growth Factor Receptor (EGFR) signaling as a downstream target of the components of Ethnodyne Visio™. Our analysis reveals that Ethnodyne Visio™ potentially regulates VEGF signaling through the EGFR pathway. Citation Format: Rishab Rajeev Samant, Rajeev Samant. Ethnodyne Visio™ affects EGFR signaling in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5968.

Upregulation of miR-33 Exacerbates Heat-Stress-Induced Apoptosis in Granulosa Cell and Follicular Atresia of Nile Tilapia (Oreochromis niloticus) by Targeting TGFβ1I1.

High temperature affects egg quality and increases follicular atresia in teleosts. The present study aimed to explore the regulated mechanism of ovary syndrome of Nile tilapia (Oreochromis niloticus) exposed to heat stress. To this end, we conducted histological and biochemical analyses and integrated miRNA-target gene analyses. The histochemical analyses confirmed that heat stress promoted the apoptosis of granulosa cell and therefore resulted in increased follicular atresia in the ovary. Heat stress led to the differential expression of multiple miRNAs (miR-27e, -27b-3p, -33, -34a -133a-5p, and -301b-5p). In a luciferase activity assay, miR-33 bound to the 3′-untranslated region (UTR) of the TGFβ1I1 (transforming growth factor-β1-induced transcript 1) gene and inhibited its expression. A TGFβ1I1 gene signal was detected in the granulosa cells of Nile tilapia by immunohistochemical analysis. Up-regulation of the miR-33 of tilapia at 6 d and 12 d exposed to heat (34.5 °C ± 0.5 °C) had significant down-regulation of the TGFβ1I1 expression of the gene and protein in tilapia ovaries. An miRNA-target gene integrated analysis revealed that miR-33 and TGFβ1I1 function in an apoptosis-related signal pathway. The signal transduction of the vascular endothelial growth factor (VEGF) family members VEGFA and its receptor (KDR) in the heat-stressed group decreased significantly compared with the control group. Transcript-levels of the Bax and Caspase-3 as apoptotic promotors were activated and Bcl-2 and Caspase-8 as apoptotic inhibitors were suppressed in the heat-stressed tilapia. These results suggest that heat stress increases the expression of miR-33, which targets TGFβ1I1 and inhibits its expression, resulting in decreased levels of follicle-stimulating hormone and 17β-estradiol and increased apoptosis by suppressing VEGF signaling, eventually inducing follicular atresia. In conclusion, our results show that the miR-33/TGFβ1I1 axis of Nile tilapia is involved in the follicular development of broodstock, and can suppress VEGF signaling to accelerate follicular atresia. Our findings demonstrate the suppressive role of miR-33 during oocyte development in Nile tilapia.

Mechanical forces couple bone matrix mineralization with inhibition of angiogenesis to limit adolescent bone growth

Bone growth requires a specialised, highly angiogenic blood vessel subtype, so-called type H vessels, which pave the way for osteoblasts surrounding these vessels. At the end of adolescence, type H vessels differentiate into quiescent type L endothelium lacking the capacity to promote bone growth. Until now, the signals that switch off type H vessel identity and thus limit adolescent bone growth have remained ill defined. Here we show that mechanical forces, associated with increased body weight at the end of adolescence, trigger the mechanoreceptor PIEZO1 and thereby mediate enhanced production of the kinase FAM20C in osteoblasts. FAM20C, the major kinase of the secreted phosphoproteome, phosphorylates dentin matrix protein 1, previously identified as a key factor in bone mineralization. Thereupon, dentin matrix protein 1 is secreted from osteoblasts in a burst-like manner. Extracellular dentin matrix protein 1 inhibits vascular endothelial growth factor signalling by preventing phosphorylation of vascular endothelial growth factor receptor 2. Hence, secreted dentin matrix protein 1 transforms type H vessels into type L to limit bone growth activity and enhance bone mineralization. The discovered mechanism may suggest new options for the treatment of diseases characterised by aberrant activity of bone and vessels such as osteoarthritis, osteoporosis and osteosarcoma.

The Anti-Angiogenic and Anti-Proliferative Activity of Methyl Hydroxychalcone.

Objective:Angiogenesis plays a key role in tumor growth, invasion, and metastasis of cancer diseases, and therefore, the inhibition of angiogenesis can provide an important therapeutic approach in cancer diseases. The aim of this study was to investigate the inhibitory effects of methyl hydroxychalcone on ex vivo sprouting of rat aortic micro-vessels and in vivo formation of chorionic plexus in chick chorioallantoic membrane and to investigate the mechanism underlying anti-angiogenic activity. Methods:Rat aortic rings were sectioned by 1 mm. 500μl of 3 mg/ml of fibrinogen in serum free M199 growth medium was added to each well with 5 ug/ml of aprotinin. Methyl hydroxychalcone at varying concentrations ranging from 6.25 µg/ml to 100 µg/ml was added to the complete growth medium. Fertilized chicken eggs were incubated at 37°C. On day 3, a small window was opened in the shell. The window was sealed with adhesive tape and incubated until day 5. One mg of methylhydroxychalcone was applied. Images of each CAM were captured using a digital camera, and the dimensions of the blood vessels were measured digitally. Vascular endothelial growth factor (VEGF)-induced human umbilical vein endothelial cell (HUVEC) proliferation and tube formation assays were examined. Additionally, VEGF-165 levels and expression of membrane VEGF receptor-2 in HUVEC lysates have been assessed.Results: The data showed that methyl hydroxychalcone significantly had antiangiogenic activity in a dose dependent manner in the rat aorta assay and had significant perturbation activity on blood vessels in the CAM assay. Methyl hydroxychalcone significantly inhibited proliferation and capillary-like tube formation in VEGF-induced HUVEC. Moreover, methylhydroxychalcone significantly reduced VEGF-165 levels in HUVECs lysate. Conclusion:This study showed that methyl hydroxychalcone significantly inhibits the angiogenesis process, blocking the VEGF signaling pathway in HUVECs and could be a potential promising angiogenesis inhibitor lead compound.

Sodium pentaborate pentahydrate promotes hair growth through the Wnt/β-catenin pathway and growth factors

BackgroundBoron (B) is an element involved in many physiological processes in humans and accelerates wound healing and increases angiogenesis. This study aimed to evaluate the possible effects of sodium pentaborate pentahydrate (NaB) on hair growth and reveal its effects on Wnt-1, β-catenin, vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and transforming growth factor-β1 (TGF-β1) signaling pathways, which are important molecular mechanisms involved in hair growth. MethodsThirty-five Sprague-Dawley/Wistar albino rats were randomly divided into five groups: non-shaved control, shaved control, NaB 1 mg (shaved + NaB 1 mg elemental B/kg CA), NaB 2 mg (shaved + NaB 2 mg elemental B/kg CA), and NaB 4 mg (shaved + NaB 4 mg elemental B/kg CA). Hair density was measured using the trichoscopy method. Dorsal skin samples were examined histopathologically at the end of the 42nd day, and follicle count, follicle diameter, and subcutaneous tissue thickness were recorded. Wnt-1, β-catenin, PDGF, VEGF, TGF-β1, and collagen I levels were analyzed with the Western blot method. ResultsIn trichoscopy measurements, hair density increased in the NaB 4 mg group (90.9%). In histopathological examination, anagen follicles were observed to increase in the NaB 1 mg and 2 mg groups (p < 0.05). Follicle diameter increased in all NaB groups (p < 0.05). The Wnt-1, β-catenin, PDGF, VEGF, TGF-β1, and collagen I level increased in the NaB 1 mg and 2 mg groups (p < 0.05), but they were similar in the NaB 4 mg group compared to the control groups (p > 0.05). ConclusionNaB 1 and 2 mg B/kg supplementation induces the anagen phase in rats via Wnt-1, β-catenin, VEGF, PDGF, and TGF-β1 signaling pathways. NaB 4 mg B/kg suppresses these pathways and adversely affects hair growth.

Milk fat-globule epidermal growth factor 8: A potential Regulator of Cutaneous Wound Healing.

Destroying the integrity of the skin may causes disability and even death from injury or illness. Wound healing is a core mechanism to maintain skin barrier function. Milk fat-globule epidermal growth factor 8 (MFG-E8) is a key factor in wound healing and is involved in regulating blood coagulation, mediating macrophage uptake of apoptotic cells, shifting macrophages from an inflammatory to an anti-inflammatory phenotype, promoting angiogenesis, enhancing vascular endothelial growth factor (VEGF) signaling, and assisting wound tissue perfusion. However, these abilities are dysregulated in pathological conditions, such as glucose disorders and ischemic injury. Restricted application of exogenous MFG-E8 can restore function and play a beneficial role in cutaneous wound healing.

Chlorinated benzothiadiazines inhibit angiogenesis through suppression of VEGFR2 phosphorylation

Angiogenesis inhibitors are a critical pharmacological tool for the treatment of solid tumors. Suppressing vascular permeability leads to inhibition of tumor growth, invasion, and metastatic potential by blocking the supply of oxygen and nutrients. Disruption of the vascular endothelial growth factor (VEGF) signaling pathway is a validated target for the design of antiangiogenic agents. Several VEGFR2 inhibitors have been clinically approved over the past years. Structural analysis of these clinical VEGFR2 inhibitors highlighted key functional group overlap with the benzothiadiazine core contained in a library of in-house compounds. Herein we ascribe anti-angiogenic activity to a series of chlorinated benzothiadiazines. Selected compounds show significant activity to completely ameliorate VEGF-induced endothelial cell proliferation by suppression of VEGFR2 phosphorylation. The scaffold is devoid of activity to inhibit carbonic anhydrases and generally lacks cytotoxicity across a range of cancer and non-malignant cell lines. Assay of activity at 468 kinases shows remarkable selectivity with only four kinases inhibited > 65% at 10 µM concentration, and with significant activity to inhibit TNK2/ACK1 and PKRD2 by > 90%. All four identified kinase targets are known modulators of angiogenesis, thus highlighting compound 17b as a novel angiogenesis inhibitor for further development.

VEGF Receptor 1 Promotes Hypoxia-Induced Hematopoietic Progenitor Proliferation and Differentiation.

Although it is well known that hypoxia incites unleashed cellular inflammation, the mechanisms of exaggerated cellular inflammation in hypoxic conditions are not known. We observed augmented proliferation of hematopoietic stem and progenitor cells (HSPC), precursors of inflammatory leukocytes, in mice under hypoxia. Consistently, a transcriptomic analysis of human HSPC exposed to hypoxic conditions revealed elevated expression of genes involved in progenitor proliferation and differentiation. Additionally, bone marrow cells in mice expressed high amount of vascular endothelial growth factor (VEGF), and HSPC elevated VEGF receptor 1 (VEGFr1) and its target genes in hypoxic conditions. In line with this, VEGFr1 blockade in vivo and in vitro decreased HSPC proliferation and attenuated inflammation. In silico and ChIP experiments demonstrated that HIF-1α binds to the promoter region of VEGFR1. Correspondingly, HIF1a silencing decreased VEGFr1 expression in HSPC and diminished their proliferation. These results indicate that VEGF signaling in HSPC is an important mediator of their proliferation and differentiation in hypoxia-induced inflammation and represents a potential therapeutic target to prevent aberrant inflammation in hypoxia-associated diseases.

Treatment of malignant pleural effusion in non-small cell lung cancer with VEGF-directed therapy

Background Vascular endothelial growth factor (VEGF) is a critical regulator of malignant pleural effusion (MPE) in non-small-cell lung cancer (NSCLC). Bevacizumab (BEV) and apatinib (APA) are novel VEGF blockers that inhibit lung cancer cell proliferation and the development of pleural effusion. Methods In this study, we established Lewis lung cancer (LLC) xenograft mouse models to compare the therapeutic effect of APA and BEV in combination with cisplatin (CDDP) against MPE. The anti-tumour and anti-angiogenic effects of this combination therapy were evaluated by 18F-FDG PET/CT imaging, TUNEL assay and Immunohistochemistry. Results The triple drug combination significantly prolonged the overall survival of the tumour-bearing mice by reducing MPE and glucose metabolism and was more effective in lowering VEGF/soluble VEGFR-2 levels in the serum and pleural exudates compared to either of the monotherapies. Furthermore, CDDP + APA + BEV promoted in vivo apoptosis and decreased microvessel density. Conclusions Mechanistically, LLC-induced MPE was inhibited by targeting the VEGF-MEK/ERK pathways. Further studies are needed to establish the synergistic therapeutic effect of these drugs in NSCLC patients with MPE. KEY MESSAGES Combined treatment of MPE with apatinib, bevacizumab and cisplatin can prolong the survival time of mice, reduce the content of MPE, decrease the SUVmax of thoracic tumour tissue, down-regulate the content of VEGF and sVEGFR-2 in serum and pleural fluid, and promote the apoptosis of tumour cells. Angiogenesis and MPE formation can be inhibited by down-regulation of HIF-1α, VEGF, VEGFR-2, MEK1 and MMP-2 molecular signalling pathway proteins.

MO421: Chronic Kidney Disease is Associated With Cardiac Downregulation of Vascular Endothelial Growth Factor a (VEGFA) and Development of Diastolic Dysfunction: Epigenetics and Micrornas

Abstract BACKGROUND AND AIMS Patients with chronic kidney disease (CKD) have a higher risk to develop heart failure with preserved ejection fraction (HFpEF). We showed in a swine model of CKD with diastolic dysfunction and cardiac remodelling that these cardiac features are associated with blunted cardiac mRNA and protein expression of vascular endothelial growth factor (VEGF), a pro-angiogenic cytokine that plays important roles in cardiac vascular development, morphogenesis and contractility. Hence, we aim to identify potential underlying mechanisms of cardiac VEGF downregulation in CKD. METHOD CKD and normal pigs (n = 3 each) were studied for 14 weeks. Cardiac morphology and function (echocardiography) were quantified in vivo and microvascular density (3D micro-CT) ex vivo. Then, cardiac micro-RNA (miRNA) and 5-hydroxymethylcytosine (5-hmC) profiles of VEGFA gene were examined by hydroxymethylated DNA immunoprecipitation and miRNA sequencing (hMeDIP-seq and miRNA-seq, respectively) and validated by qPCR and Western blotting. RESULTS Blunted renal function in CKD pigs associated with left ventricular (LV) hypertrophy, and abnormal LV strain and diastolic dysfunction with pEF (Figure 1A) and reduced subendocardial microvascular density (Figure 1B) compared to normal. miRNA-seq showed that mir-183 was the only miRNA capable of targeting VEGFA and upregulated in CKD hearts (Figure 1C), accompanied by downregulation of VEGFA gene and VEGF protein (Figure 1D), whereas hMeDIP-seq revealed reduced VEGFA 5hmC levels in the hearts of CKD versus normal pigs (Figure 1E). CONCLUSION Our study suggests that miRNA-modulation and cardiac epigenetic changes in VEGF might contribute to cardiac damage and the development of HF in CKD. These observations may assist in developing novel therapies, like miRNA antagonists or epigenetic modulators, to preserve VEGF signalling and protect the heart in patients with CKD.

Circ 003390/Eukaryotic translation initiation factor 4A3 promoted cell migration and proliferation in endometrial cancer via vascular endothelial growth factor signaling by miR-195-5p

ABSTRACT The differential expression of circRNA in different biological samples renders it as an ideal biomarker for disease diagnosis and identification of tissue development. In addition, the gradual clarification of the mode of action of circRNA in disease makes it as a potential therapeutic target. The purpose of this study is to investigate the role and regulating mechanism of circular RNA has circ 003390 (circWEE1) on Endometrial cancer (EC) genesis. To estimate clinical values of circWEE1 on cell migration and proliferation in EC, and its possible mechanisms. The expression of circWEE1 and EIF4A3in EC cells have been evaluated using qPCR and Western blot. The expression of circWEE1 and EIF4A3 levels were increased in patients with EC. Over-expression of circWEE1 or down-regulation of miR-195-5p promoted cell migration and proliferation in EC. Next, we verified that eIF4A3 binds to the circWEE1 mRNA transcript, circWEE1 served as a sponge that directly targeted miR-195-5p. Bioinformatics prediction forecast that miR-195-5p directly targeted VEGF at 3’-UTR, which was confirmed by luciferase reporter assay. Our findings indicate that Circular RNA hsa circWEE1/EIF4A3 promoted cell migration and proliferation in EC via VEGF signaling by miR-195-5p, which could provide pivotal potential therapeutic targets for the treatment of EC.

Endothelial Regulation of Microvascular Growth and Stability by Ang‐Tie and VEGF Signaling Pathways: A Mechanistic Computational Systems Biology Model

The Angiopoietin‐Tie (Ang‐Tie) pathway is a key signaling pathway regulating vascular stability and permeability, and it significantly intersects and crosstalk with the vascular endothelial growth factor (VEGF) signaling pathway, a major signaling pathway regulating angiogenesis and vascular permeability. Disrupted Ang‐Tie and VEGF signaling is linked to vascular dysfunction related to cancer, systemic inflammation, cardiovascular disease, and diabetic macular edema. Ang‐Tie pathway is regulated by various molecular mechanisms, including ligand‐receptor interactions, receptor multimerization, binding of co‐receptor Tie1, inhibition by vascular endothelial protein tyrosine phosphatase (VE‐PTP), receptor extracellular domain shedding, junctional localization, trafficking, and turnover. VEGF pathway is regulated by ligand binding, homo‐ and heterodimerization of VEGF receptors VEGFR1 and VEGFR2, interaction with neuropilin, thrombospondin‐1/CD47, receptor internalization, recycling, and degradation. Ang‐Tie and VEGF signaling pathways also share crosstalk mechanisms and integrative downstream signaling through phosphoinositide 3‐kinases (PI3K)/Akt, sphingosine‐dependent Erk activation, Src sequestration via RhoA/mDia, and calcium cycling, forming a complex reaction network that requires an integrative model to study the signaling outcomes on a systems level. The present study uses a mechanistic computational model of the Ang‐Tie and VEGF signaling pathways, their regulatory mechanisms, crosstalk, and integrative downstream signaling to quantitatively characterize the molecular control of vascular growth, permeability, and stability by endothelial cells. The model captures and reproduces key experimental observations of the Ang‐Tie/VEGF signaling network with detailed molecular mechanisms. The model significantly expands our previous computational models of the Ang‐Tie signaling pathway [1,2] and integrates our systems biology understanding of the VEGF pathway and their crosstalk. The model serves as a platform for quantitatively predicting the signaling outcome of varying ligand concentrations and receptor expressions in physiological and pathological conditions, identifying molecular mechanisms and targets for therapeutic interventions targeting the signaling network, and simulating the effects of drugs and their combinations on the signaling outcome on a network level.

Phosphatase and Tensin Homology Deletion Gene (PTEN) Regulates Fibroblast Precursor Cells Autophagy and Vascular Endothelial Growth Factor Signaling in Preeclampsia

Preeclampsia (PE) causes serious harm to the health of mothers and infants. PTEN regulates cell biological behaviors, but its role in preeclampsia have not been reported. Real time PCR and Western blot detected PTEN level in the placenta of PE patients and controls. Placental trophoblastderived cell line HTR8 was assigned into NC group, PTEN group and si-PTEN inhibitor group followed by measuring PTEN level, cell proliferation by MTT assay, cell invasion by Transwell, Caspase 3 activity, Beclin-1 and Atg-5 expression as well as PI3K/Akt/HIF-1α/VEGF signaling protein by Western blot. PTEN in PE patients was significantly downregulated (P &lt; 0.05). Transfection of PTEN siRNA significantly down-regulated PTEN, promoted cell proliferation and invasion, reduced Caspase 3 activity, increased Beclin-1 and Atg-5, and PI3K/Akt/HIF-1α/VEGF protein expression (P &lt; 0.05). Transfection of pcDNA 3.0-PTEN up-regulated PTEN and significantly reversed the above changes (P &lt; 0.05). In conclusion, PTEN is reduced in PE and it can regulate pre-eclampsia trophoblast autophagy possibly through PI3K/Akt/HIF-1α/VEGF signaling, suggesting that PTEN can be a potential target for PE therapy.

Eugenol suppresses the proliferation and invasion of TNF-α-induced fibroblast-like synoviocytes via regulating NF-κB and COX-2

Eugenol (4-allyl -2- methoxyphenol), reportedly, a native compound that widely exists in a variety of plants, shows diverse biological activities such as anti-bacteria, anti-inflammation and anti-oxidation. This work was to delve into the effects and molecular mechanisms of eugenol on the phenotypes of fibroblast-like synovial cells from rheumatoid arthritis (RA). Fibroblast-like synovial cells treated with tumor necrosis factor-α (TNF-α) for 24 h received eugenol treatment. In this study, we found eugenol could inhibit TNF-α-induced proliferation, migration, invasion, angiogenesis and inflammatory response of fibroblast-like synovial cells, and promote apoptosis. Eugenol's target genes were significantly associated with vascular endothelial growth factor (VEGF) and NF-kappaB (NF-κB) signaling pathway. Eugenol reversed the promoting effect of TNF-α on the expression of NF-κB signaling pathway-related proteins as well as prostaglandin-endoperoxide synthase 2 (PTGS2, also known as COX-2) protein. In addition, the NF-κB pathway inhibitor Bay11-7082 markedly restrained the viability, migration, aggressiveness, and angiogenic and inflammatory responses of TNF-α-induced fibroblast-like synovial cells and promoted apoptosis. In conclusion, eugenol may represent a novel drug to suppress the progression of RA by inhibiting NF-κB signaling pathway and COX-2 expression in fibroblast-like synovial cells.

Distinct regulatory states control the elongation of individual skeletal rods in the sea urchin embryo.

BackgroundUnderstanding how gene regulatory networks (GRNs) control developmental progression is a key to the mechanistic understanding of morphogenesis. The sea urchin larval skeletogenesis provides an excellent platform to tackle this question. In the early stages of sea urchin skeletogenesis, skeletogenic genes are uniformly expressed in the skeletogenic lineage. Yet, during skeletal elongation, skeletogenic genes are expressed in distinct spatial sub‐domains. The regulation of differential gene expression during late skeletogenesis is not well understood.ResultsHere we reveal the dynamic expression of the skeletogenic regulatory genes that define a specific regulatory state for each pair of skeletal rods, in the sea urchin Paracentrotus lividus. The vascular endothelial growth factor (VEGF) signaling, essential for skeleton formation, specifically controls the migration of cells that form the postoral and distal anterolateral skeletogenic rods. VEGF signaling also controls the expression of regulatory genes in cells at the tips of the postoral rods, including the transcription factors Pitx1 and MyoD1. Pitx1 activity is required for normal skeletal elongation and for the expression of some of VEGF target genes.ConclusionsOur study illuminates the fine‐tuning of the regulatory system during the transition from early to late skeletogenesis that gives rise to rod‐specific regulatory states.

Naoluo Xintong Decoction Ameliorates Cerebral Ischemia-Reperfusion Injury by Promoting Angiogenesis through Activating the HIF-1α/VEGF Signaling Pathway in Rats.

Background Naoluo Xintong decoction (NLXTD) is a traditional Chinese medicine (TCM) formula which has been used to improve neuronal functional recovery after cerebral ischemic stroke. However, the molecular mechanism underlying NLXTD's amelioration of ischemic stroke remains unclear. The present study was designed to explore the effect and mechanism of NLXTD on brain angiogenesis in a rat model with cerebral ischemia-reperfusion (I/R) injury targeting the hypoxia-inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF) pathway. Materials and Methods Cerebral I/R model was established by the classical middle cerebral artery occlusion (MCAO) method. Sprague-Dawley (SD) male rats (n = 80) were randomly divided into the sham-operation group, the model group, the HIF-1α inhibitor 2-methoxyestradiol (2ME2) group, the 2ME2 with NLXTD group, and the NLXTD group. Neurological deficit test, TTC staining, H&E staining, TUNEL staining, immunohistochemistry (IH), immunofluorescence (IF), western blot, and quantitative RT-PCR were performed to evaluate the effect of NLXTD after MCAO. Results Administration of NLXTD significantly decreased neuron deficiency scores, reduced brain infarct volume, and lowered damaged and apoptotic cells after brain I/R injury in rats. Meanwhile, NLXTD had a protective effect on angiogenesis by increasing the MVD and the expressions of BrdU and CD34, which enhanced the number of endothelial cells in the ischemic penumbra brain. NLXTD treatment significantly raised the protein and mRNA levels of HIF-1α, VEGF, VEGFR2, and Notch1 compared with the model treatment. In contrast, a specific HIF-1α inhibitor, 2ME2, inhibited the improvement of neurological function and angiogenesis in NLXTD-induced rats with cerebral I/R injury, suggesting that NLXTD played a positive role in ischemic brain injury by activating the HIF-1α/VEGF signaling pathway. Conclusions NLXTD exerts neuroprotection targeting angiogenesis by upregulating the HIF-1α/VEGF signaling pathway on cerebral I/R injury rats.

Context Dependent Sulf1/Sulf2 Functional Divergence in Endothelial Cell Activity.

Signalling activities are tightly regulated to control cellular responses. Heparan sulfate proteoglycans (HSPGs) at the cell membrane and extracellular matrix regulate ligand availability and interaction with a range of key receptors. SULF1 and SULF2 enzymes modify HSPG sulfation by removing 6-O sulfates to regulate cell signalling but are considered functionally identical. Our in vitro mRNA and protein analyses of two diverse human endothelial cell lines, however, highlight their markedly distinct regulatory roles of maintaining specific HSPG sulfation patterns through feedback regulation of HS 6-O transferase (HS6ST) activities and highly divergent roles in vascular endothelial growth factor (VEGF) and Transforming growth factor β (TGFβ) cell signalling activities. Unlike Sulf2, Sulf1 over-expression in dermal microvascular HMec1 cells promotes TGFβ and VEGF cell signalling by simultaneously upregulating HS6ST1 activity. In contrast, Sulf1 over-expression in venous ea926 cells has the opposite effect as it attenuates both TGFβ and VEGF signalling while Sulf2 over-expression maintains the control phenotype. Exposure of these cells to VEGF-A, TGFβ1, and their inhibitors further highlights their endothelial cell type-specific responses and integral growth factor interactions to regulate cell signalling and selective feedback regulation of HSPG sulfation that additionally exploits alternative Sulf2 RNA-splicing to regulate net VEGF-A and TGFβ cell signalling activities.

MiR-155 regulates physiological angiogenesis but an miR-155-rich microenvironment disrupts the process by promoting unproductive endothelial sprouting.

Angiogenesis involves cell specification orchestrated by regulatory interactions between the vascular endothelial growth factor and Notch signaling pathways. However, the role of microRNAs in these regulations remains poorly explored. Here we show that a controlled level of miR-155 is essential for proper angiogenesis. In the mouse retina angiogenesis model, antimiR-155 altered neovascularization. In vitro assays established that endogenous miR-155 is involved in podosome formation, activation of the proteolytic machinery and cell migration but not in morphogenesis. The role of miR-155 was explored using miR-155 mimics. In vivo, exposing the developing vasculature to miR-155 promoted hypersprouting, thus phenocopying defects associated with Notch deficiency. Mechanistically, miR-155 overexpression weakened Notch signaling by reducing Smad1/5 expression, leading to the formation of tip cell-like cells which did not reach full invasive capacity and became unable to undergo morphogenesis. These results identify miR-155 as a novel regulator of physiological angiogenesis and as a novel actor of pathological angiogenesis.

Therapeutic Effect of Cu(II) Complex with Photocatalytic Property on Gastric Cancer by Inhibiting the Proliferation of Tumor Cells

In situ hydrolysis of 1,4,5,8-naphthalenetetracarboxylic dianhydride (L) and simultaneous self-assembly with Cu(II) ions afforded a new Cu(II) compound formulated as [Cu(L) (4,4′-bpy)0.5(H2O)]n (1), which is structurally determined by a series of characterization techniques, such as powder X-ray diffraction (PXRD), thermogravimetric Analysis (TGA), and elemental analysis. It is noteworthy that compound 1 can catalyze the degradation of methylene blue (MB) in aqueous solution under UV irradiation. This paper also investigated and evaluated its application value and research mechanism in gastric cancer. However, we also used real-time reverse transcription-polymerase chain reaction (RT-PCR) to detect the activation of vascular endothelial growth factor (VEGF) signaling pathway, and Cell Counting Kit-8 (CCK-8) method was used to calculate the inhibition activity of 1 on gastric cancer cell viability.

Astrocytes Protect Human Brain Microvascular Endothelial Cells from Hypoxia Injury by Regulating VEGF Expression.

Hypoxic-ischemic stroke has been associated with changes in neurovascular behavior, mediated, in part, by induction of the vascular endothelial growth factor (VEGF). The objective of this study was to investigate the effects of human astrocytes on the proliferation, apoptosis, and function of human microvascular endothelial cells (hBMEC) in vitro. Human microvascular endothelial cells (hBMEC) and human normal astrocytes (HA-1800) were used to establish in vitro cocultured cell models. The coculture model was used to simulate hypoxic-ischemic stroke, and it was found that astrocytes could promote hBMEC proliferation, inhibit apoptosis, reduce cell damage, and enhance antioxidant capacity by activating the VEGF signaling pathway. When VEGF is knocked out in astrocytes, the protective effect of astrocytes on hBMEC was partially lost. In conclusion, our study confirms the protective effect of hBMEC and laid a foundation for the study of hypoxic-ischemic stroke.