Science.gov

Sample records for azd2171 inhibits endothelial

  1. The Vascular Endothelial Growth Factor Receptor-2 Tyrosine Kinase Inhibitor Cediranib (Recentin; AZD2171) Inhibits Endothelial Cell Function and Growth of Human Renal Tumor Xenografts

    SciTech Connect

    Siemann, Dietmar W. Brazelle, W.D.; Juergensmeier, Juliane M.

    2009-03-01

    Purpose: The goal of this study was to examine the therapeutic potential of the vascular endothelial growth factor (VEGF) signaling inhibitor cediranib in a human model of renal cell carcinoma (Caki-1). Methods and Materials: The effects of cediranib treatment on in vitro endothelial cell function (proliferation, migration, and tube formation), as well as in vivo angiogenesis and tumor growth, were determined. Results: In vitro, cediranib significantly impaired the proliferation and migration of endothelial cells and their ability to form tubes, but had no effect on the proliferation of Caki-1 tumor cells. In vivo, cediranib significantly reduced Caki-1 tumor cell-induced angiogenesis, reduced tumor perfusion, and inhibited the growth of Caki-1 tumor xenografts. Conclusions: The present results are consistent with the notion that inhibition of VEGF signaling leads to an indirect (i.e., antiangiogenic) antitumor effect, rather than a direct effect on tumor cells. These results further suggest that inhibition of VEGF signaling with cediranib may impair the growth of renal cell carcinoma.

  2. A phase II study of AZD2171 (cediranib) in the treatment of patients with acute myeloid leukemia or high-risk myelodysplastic syndrome.

    PubMed

    Mattison, Ryan; Jumonville, Alcee; Flynn, Patrick James; Moreno-Aspitia, Alvaro; Erlichman, Charles; LaPlant, Betsy; Juckett, Mark B

    2015-07-01

    Patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) not fit for intensive treatment need novel therapy options. Vascular endothelial growth factor (VEGF) receptor inhibition is one potential mechanism by which AML and MDS could be treated. The receptor tyrosine kinase inhibitor AZD2171 (cediranib) has activity against VEGF receptors KDR and FLT-1. This multicenter phase II study was designed to test cediranib's activity in patients with AML or high-risk MDS. The primary endpoint was confirmed disease response defined as a composite of complete remission, partial remission or hematologic improvement. The study enrolled 23 subjects in the AML cohort and 16 subjects in the MDS cohort. There were no confirmed responses in either group. Since the study met the stopping rule after the first stage of enrollment, the trial was closed to further accrual. Common adverse events in both cohorts included thrombocytopenia, neutropenia, anemia, fatigue, dyspnea, diarrhea, nausea and dehydration.

  3. Cediranib (AZD2171) in Patients with Advanced Hepatocellular Carcinoma: A Phase II North Central Cancer Treatment Group (NCCTG) Clinical Trial1

    PubMed Central

    Alberts, Steven R.; Fitch, Tom R.; Kim, George P.; Morlan, Bruce W.; Dakhil, Shaker R.; Gross, Howard M.; Nair, Suresh

    2011-01-01

    Objectives Vascular endothelial growth factor (VEGF) has been shown to be overexpressed in several studies of hepatocellular carcinoma (HCC). Cediranib is a potent inhibitor of VEGF signaling. We assessed the efficacy and toxicity of cediranib in patients with HCC. Methods Twenty-eight patients with unresectable or metastatic HCC were enrolled on this study. Patients received 45 mg of cediranib orally, once daily, for 28 day cycles. The primary objective of this Phase II study was to assess six-month survival. Secondary objectives were to assess tumor response, time-to-progression, and toxicity. Results All 28 patients were evaluable for efficacy outcomes. Twelve patients (42.9%) survived 6 months, 15 (53.6%) died within 6 months, and one (3.6%) was lost to follow-up before 6 months. The median overall survival was 5.8 months (95% CI: 3.4–7.3 months). No patients experienced confirmed response. The median time-to-progression was 2.8 months (95% CI: 2.3 – 4.4 months). Twenty-six patients (93%) experienced a grade 3+ adverse event (AE) with the most common AEs being fatigue (46%), anorexia (25%), hypertension (21%), and elevated alanine aminotransferase (ALT) (18%). Conclusions Due to toxicity, cediranib at this dose and schedule is not an effective treatment in patients with unresectable or metastatic HCC. PMID:21422991

  4. Epigallocatechin gallate inhibits endothelial exocytosis.

    PubMed

    Yamakuchi, Munekazu; Bao, Clare; Ferlito, Marcella; Lowenstein, Charles J

    2008-07-01

    Consumption of green tea is associated with a decrease in cardiovascular mortality. The beneficial health effects of green tea are attributed in part to polyphenols, organic compounds found in tea that lower blood pressure, reduce body fat, decrease LDL cholesterol, and inhibit inflammation. We hypothesized that epigallocatechin gallate (EGCG), the most abundant polyphenol in tea, inhibits endothelial exocytosis, the initial step in leukocyte trafficking and vascular inflammation. To test this hypothesis, we treated human umbilical-vein endothelial cells with EGCG and other polyphenols, and then measured endothelial exocytosis. We found that EGCG decreases endothelial exocytosis in a concentration-dependent manner, with the effects most prominent after 4 h of treatment. Other catechin polyphenols had no effect on endothelial cells. By inhibiting endothelial exocytosis, EGCG decreases leukocyte adherence to endothelial cells. In searching for the mechanism by which EGCG affects endothelial cells, we found that EGCG increases Akt phosphorylation, eNOS phosphorylation, and nitric oxide (NO) production. NOS inhibition revealed that NO mediates the anti-inflammatory effects of EGCG. Our data suggest that polyphenols can decrease vascular inflammation by increasing the synthesis of NO, which blocks endothelial exocytosis.

  5. A Phase 1 trial of the poly(ADP-ribose) polymerase inhibitor olaparib (AZD2281) in combination with the anti-angiogenic cediranib (AZD2171) in recurrent epithelial ovarian or triple-negative breast cancer.

    PubMed

    Liu, Joyce F; Tolaney, Sara M; Birrer, Michael; Fleming, Gini F; Buss, Mary K; Dahlberg, Suzanne E; Lee, Hang; Whalen, Christin; Tyburski, Karin; Winer, Eric; Ivy, Percy; Matulonis, Ursula A

    2013-09-01

    Poly(ADP-ribose) polymerase (PARP)-inhibitors and anti-angiogenics have activity in recurrent ovarian and breast cancer; however, the effect of combined therapy against PARP and angiogenesis in this population has not been reported. We investigated the toxicities and recommended phase 2 dosing (RP2D) of the combination of cediranib, a multitargeted inhibitor of vascular endothelial growth factor receptor (VEGFR)-1/2/3 and olaparib, a PARP-inhibitor (NCT01116648). Cediranib tablets once daily and olaparib capsules twice daily were administered orally in a standard 3+3 dose escalation design. Patients with recurrent ovarian or metastatic triple-negative breast cancer were eligible. Patients had measurable disease by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 or met Gynecologic Cancer InterGroup (GCIG) CA125 criteria. No prior PARP-inhibitors or anti-angiogenics in the recurrent setting were allowed. 28 patients (20 ovarian, 8 breast) enrolled to 4 dose levels. 2 dose limiting toxicities (DLTs) (1 grade 4 neutropenia ≥ 4 days; 1 grade 4 thrombocytopenia) occurred at the highest dose level (cediranib 30 mg daily; olaparib 400 mg twice daily [BID]). The RP2D was cediranib 30 mg daily and olaparib 200 mg BID. Grade 3 or higher toxicities occurred in 75% of patients, and included grade 3 hypertension (25%) and grade 3 fatigue (18%). One grade 3 bowel obstruction occurred. The overall response rate (ORR) in the 18 RECIST-evaluable ovarian cancer patients was 44%, with a clinical benefit rate (ORR plus stable disease (SD) > 24 weeks) of 61%. None of the seven evaluable breast cancer patients achieved clinical response; two patients had stable disease for > 24 weeks. The combination of cediranib and olaparib has haematologic DLTs and anticipated class toxicities, with promising evidence of activity in ovarian cancer patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Sickle erythrocytes inhibit human endothelial cell DNA synthesis

    SciTech Connect

    Weinstein, R.; Zhou, M.A.; Bartlett-Pandite, A.; Wenc, K. )

    1990-11-15

    Patients with sickle cell anemia experience severe vascular occlusive phenomena including acute pain crisis and cerebral infarction. Obstruction occurs at both the microvascular and the arterial level, and the clinical presentation of vascular events is heterogeneous, suggesting a complex etiology. Interaction between sickle erythrocytes and the endothelium may contribute to vascular occlusion due to alteration of endothelial function. To investigate this hypothesis, human vascular endothelial cells were overlaid with sickle or normal erythrocytes and stimulated to synthesize DNA. The erythrocytes were sedimented onto replicate monolayers by centrifugation for 10 minutes at 17 g to insure contact with the endothelial cells. Incorporation of 3H-thymidine into endothelial cell DNA was markedly inhibited during contact with sickle erythrocytes. This inhibitory effect was enhanced more than twofold when autologous sickle plasma was present during endothelial cell labeling. Normal erythrocytes, with or without autologous plasma, had a modest effect on endothelial cell DNA synthesis. When sickle erythrocytes in autologous sickle plasma were applied to endothelial monolayers for 1 minute, 10 minutes, or 1 hour and then removed, subsequent DNA synthesis by the endothelial cells was inhibited by 30% to 40%. Although adherence of sickle erythrocytes to the endothelial monolayers was observed under these experimental conditions, the effect of sickle erythrocytes on endothelial DNA synthesis occurred in the absence of significant adherence. Hence, human endothelial cell DNA synthesis is partially inhibited by contact with sickle erythrocytes. The inhibitory effect of sickle erythrocytes occurs during a brief (1 minute) contact with the endothelial monolayers, and persists for at least 6 hours of 3H-thymidine labeling.

  7. CHOP deficiency inhibits methylglyoxal-induced endothelial dysfunction.

    PubMed

    Choi, Yoon Young; Kim, Suji; Han, Jung-Hwa; Nam, Dae-Hwan; Park, Kwon Moo; Kim, Seong Yong; Woo, Chang-Hoon

    2016-11-18

    Epidemiological studies suggested that diabetic patients are susceptible to develop cardiovascular complications along with having endothelial dysfunction. It has been suggested that methylglyoxal (MGO), a glycolytic metabolite, has more detrimental effects on endothelial dysfunction rather than glucose itself. Here, we investigated the molecular mechanism by which MGO induces endothelial dysfunction via the regulation of ER stress. Biochemical data showed that 4-PBA significantly inhibited MGO-induced protein cleavages of PARP-1 and caspase-3. In addition, it was found that high glucose-induced endothelial apoptosis was enhanced in the presence of GLO1 inhibitor, suggesting the role of endogenous MGO in high glucose-induced endothelial dysfunction. MGO-induced endothelial apoptosis was significantly diminished by the depletion of CHOP with si-RNA against human CHOP, but not by SP600125, a specific inhibitor of JNK. The physiological relevance of this signaling pathway was demonstrated in CHOP deficiency mouse model, in which instillation of osmotic pump containing MGO led to aortic endothelial dysfunction. Notably, the aortic endothelial dysfunction response to MGO infusion was significantly improved in CHOP deficiency mice compared to littermate control. Taken together, these findings indicate that MGO specifically induces endothelial dysfunction in a CHOP-dependent manner, suggesting the therapeutic potential of CHOP inhibition in diabetic cardiovascular complications.

  8. Inhibition of cyclooxygenase (COX)-2 affects endothelial progenitor cell proliferation

    SciTech Connect

    Colleselli, Daniela; Bijuklic, Klaudija; Mosheimer, Birgit A.; Kaehler, Christian M. . E-mail: C.M.Kaehler@uibk.ac.at

    2006-09-10

    Growing evidence indicates that inducible cyclooxygenase-2 (COX-2) is involved in the pathogenesis of inflammatory disorders and various types of cancer. Endothelial progenitor cells recruited from the bone marrow have been shown to be involved in the formation of new vessels in malignancies and discussed for being a key point in tumour progression and metastasis. However, until now, nothing is known about an interaction between COX and endothelial progenitor cells (EPC). Expression of COX-1 and COX-2 was detected by semiquantitative RT-PCR and Western blot. Proliferation kinetics, cell cycle distribution and rate of apoptosis were analysed by MTT test and FACS analysis. Further analyses revealed an implication of Akt phosphorylation and caspase-3 activation. Both COX-1 and COX-2 expression can be found in bone-marrow-derived endothelial progenitor cells in vitro. COX-2 inhibition leads to a significant reduction in proliferation of endothelial progenitor cells by an increase in apoptosis and cell cycle arrest. COX-2 inhibition leads further to an increased cleavage of caspase-3 protein and inversely to inhibition of Akt activation. Highly proliferating endothelial progenitor cells can be targeted by selective COX-2 inhibition in vitro. These results indicate that upcoming therapy strategies in cancer patients targeting COX-2 may be effective in inhibiting tumour vasculogenesis as well as angiogenic processes.

  9. 25-Hydroxycholesterol impairs endothelial function and vasodilation by uncoupling and inhibiting endothelial nitric oxide synthase.

    PubMed

    Ou, Zhi-Jun; Chen, Jing; Dai, Wei-Ping; Liu, Xiang; Yang, Yin-Ke; Li, Yan; Lin, Ze-Bang; Wang, Tian-Tian; Wu, Ying-Ying; Su, Dan-Hong; Cheng, Tian-Pu; Wang, Zhi-Ping; Tao, Jun; Ou, Jing-Song

    2016-10-01

    Endothelial dysfunction is a key early step in atherosclerosis. 25-Hydroxycholesterol (25-OHC) is found in atherosclerotic lesions. However, whether 25-OHC promotes atherosclerosis is unclear. Here, we hypothesized that 25-OHC, a proinflammatory lipid, can impair endothelial function, which may play an important role in atherosclerosis. Bovine aortic endothelial cells were incubated with 25-OHC. Endothelial cell proliferation, migration, and tube formation were measured. Nitric oxide (NO) production and superoxide anion generation were determined. The expression and phosphorylation of endothelial NO synthase (eNOS) and Akt as well as the association of eNOS and heat shock protein (HSP)90 were detected by immunoblot analysis and immunoprecipitation. Endothelial cell apoptosis was monitored by TUNEL staining and caspase-3 activity, and expression of Bcl-2, Bax, cleaved caspase-9, and cleaved caspase-3 were detected by immunoblot analysis. Finally, aortic rings from Sprague-Dawley rats were isolated and treated with 25-OHC, and endothelium-dependent vasodilation was evaluated. 25-OHC significantly inhibited endothelial cell proliferation, migration, and tube formation. 25-OHC markedly decreased NO production and increased superoxide anion generation. 25-OHC reduced the phosphorylation of Akt and eNOS and the association of eNOS and HSP90. 25-OHC also enhanced endothelial cell apoptosis by decreasing Bcl-2 expression and increasing cleaved caspase-9 and cleaved caspase-3 expressions as well as caspase-3 activity. 25-OHC impaired endothelium-dependent vasodilation. These data demonstrated that 25-OHC could impair endothelial function by uncoupling and inhibiting eNOS activity as well as by inducing endothelial cell apoptosis. Our findings indicate that 25-OHC may play an important role in regulating atherosclerosis. Copyright © 2016 the American Physiological Society.

  10. AZD2171 in Treating Young Patients With Recurrent, Progressive, or Refractory Primary CNS Tumors

    ClinicalTrials.gov

    2016-03-04

    Childhood Atypical Teratoid/Rhabdoid Tumor; Childhood Central Nervous System Germ Cell Tumor; Childhood Cerebral Anaplastic Astrocytoma; Childhood Cerebral Astrocytoma; Childhood Grade I Meningioma; Childhood Grade II Meningioma; Childhood Grade III Meningioma; Childhood Infratentorial Ependymoma; Childhood Oligodendroglioma; Childhood Spinal Cord Neoplasm; Childhood Supratentorial Ependymoma; Recurrent Childhood Brain Neoplasm; Recurrent Childhood Brain Stem Glioma; Recurrent Childhood Cerebellar Astrocytoma; Recurrent Childhood Cerebral Astrocytoma; Recurrent Childhood Ependymoma; Recurrent Childhood Medulloblastoma; Recurrent Childhood Pineoblastoma; Recurrent Childhood Subependymal Giant Cell Astrocytoma; Recurrent Childhood Supratentorial Primitive Neuroectodermal Tumor; Recurrent Childhood Visual Pathway Glioma

  11. AZD2171 in Treating Patients With Recurrent or Stage IV Melanoma

    ClinicalTrials.gov

    2015-06-01

    Acral Lentiginous Malignant Melanoma; Ciliary Body and Choroid Melanoma, Medium/Large Size; Ciliary Body and Choroid Melanoma, Small Size; Extraocular Extension Melanoma; Intraocular Melanoma; Iris Melanoma; Lentigo Maligna Malignant Melanoma; Recurrent Melanoma; Stage, Intraocular Melanoma; Stage IV Melanoma; Superficial Spreading Malignant Melanoma

  12. Protein kinase C activators inhibit capillary endothelial cell growth

    SciTech Connect

    Doctrow, S.R.

    1986-05-01

    Phorbol 12,13-dibutyrate (PDBu) binds specifically to bovine capillary endothelial (BCE) cells (K/sub d/ = 8nM) and inhibits the proliferation (K/sub 50/ = 6 +/- 4 nM). Under similar conditions, PDBu does not inhibit the growth of bovine aortic endothelial or smooth muscle cells. PDBu markedly attenuates the response of BCE cells to purified human hepatoma-derived growth factor which, in the absence of PDBu, stimulates BCE cell growth by about 3-fold. Several observations suggest that the inhibition of BCE cell growth by PDBu is mediated by protein kinase C: (1) different phorbol compounds inhibit BCE cell growth according to the relative potencies as protein kinase C activators (12-tetradecanoylphorbol 13-acetate > PDBu >> phorbol 12,13-diacetate >>>..beta..-phorbol; ..cap alpha..-phorbol 12,13-didecanoate). (2) Specific binding of PDBu to BCE cells is displaced by sn-1,2-dioctanoylglycerol (diC/sub 8/), a protein kinase C activator and an analog of the putative second messenger activating this kinase in vivo. The weak protein kinase C activator, sn-1,2-dibutyrylglycerol, does not affect PDBu binding. (3) A cytosolic extract from BCE cells contains a Ca/sup 2 +//phosphatidylserine-dependent kinase that is activated by diC/sub 8/ and PDBu, but not by ..beta..-phorbol. These results support a role for protein kinase C in suppressing capillary endothelial cell growth and may therefore have implications in the intracellular regulation of angiogenesis.

  13. Vascular endothelial growth factor-dependent angiogenesis and dynamic vascular plasticity in the sensory circumventricular organs of adult mouse brain.

    PubMed

    Morita, Shoko; Furube, Eriko; Mannari, Tetsuya; Okuda, Hiroaki; Tatsumi, Kouko; Wanaka, Akio; Miyata, Seiji

    2015-03-01

    The sensory circumventricular organs (CVOs), which comprise the organum vasculosum of the lamina terminalis (OVLT), the subfornical organ (SFO) and the area postrema (AP), lack a typical blood-brain barrier (BBB) and monitor directly blood-derived information to regulate body fluid homeostasis, inflammation, feeding and vomiting. Until now, almost nothing has been documented about vascular features of the sensory CVOs except fenestration of vascular endothelial cells. We therefore examine whether continuous angiogenesis occurs in the sensory CVOs of adult mouse. The angiogenesis-inducing factor vascular endothelial growth factor-A (VEGF-A) and the VEGF-A-regulating transcription factor hypoxia-inducible factor-1α were highly expressed in neurons of the OVLT and SFO and in both neurons and astrocytes of the AP. Expression of the pericyte-regulating factor platelet-derived growth factor B was high in astrocytes of the sensory CVOs. Immunohistochemistry of bromodeoxyuridine and Ki-67, a nuclear protein that is associated with cellular proliferation, revealed active proliferation of endothelial cells. Moreover, immunohistochemistry of caspase-3 and the basement membrane marker laminin showed the presence of apoptosis and sprouting of endothelial cells, respectively. Treatment with the VEGF receptor-associated tyrosine kinase inhibitor AZD2171 significantly reduced proliferation and filopodia sprouting of endothelial cells, as well as the area and diameter of microvessels. The mitotic inhibitor cytosine-b-D-arabinofuranoside reduced proliferation of endothelial cells and the vascular permeability of blood-derived low-molecular-weight molecules without changing vascular area and microvessel diameter. Thus, our data indicate that continuous angiogenesis is dependent on VEGF signaling and responsible for the dynamic plasticity of vascular structure and permeability.

  14. Arginase inhibition restores endothelial function in diet-induced obesity.

    PubMed

    Chung, Ji Hyung; Moon, Jiyoung; Lee, Youn Sue; Chung, Hye-Kyung; Lee, Seung-Min; Shin, Min-Jeong

    2014-08-22

    Arginase may play a major role in the regulation of vascular function in various cardiovascular disorders by impairing nitric oxide (NO) production. In the current study, we investigated whether supplementation of the arginase inhibitor N(ω)-hydroxy-nor-l-arginine (nor-NOHA) could restore endothelial function in an animal model of diet-induced obesity. Arginase 1 expression was significantly lower in the aorta of C57BL/6J mice fed a high-fat diet (HFD) supplemented with nor-NOHA (40mgkg(-1)/day) than in mice fed HFD without nor-NOHA. Arginase inhibition led to considerable increases in eNOS expression and NO levels and significant decreases in the levels of circulating ICAM-1. These findings were further confirmed by the results of siRNA-mediated knockdown of Arg in human umbilical vein endothelial cells. In conclusion, arginase inhibition can help restore dysregulated endothelial function by increasing the eNOS-dependent NO production in the endothelium, indicating that arginase could be a therapeutic target for correcting obesity-induced vascular endothelial dysfunction.

  15. Arginase inhibition enhances angiogenesis in endothelial cells exposed to hypoxia.

    PubMed

    Wang, Lin; Bhatta, Anil; Toque, Haroldo A; Rojas, Modesto; Yao, Lin; Xu, Zhimin; Patel, Chintan; Caldwell, Ruth B; Caldwell, R William

    2015-03-01

    Hypoxia-induced arginase elevation plays an essential role in several vascular diseases but influence of arginase on hypoxia-mediated angiogenesis is completely unknown. In this study, in vitro network formation in bovine aortic endothelial cells (BAEC) was examined after exposure to hypoxia for 24h with or without arginase inhibition. Arginase activity, protein levels of the two arginase isoforms, eNOS, and VEGF as well as production of NO and ROS were examined to determine the involvement of arginase in hypoxia-mediated angiogenesis. Hypoxia elevated arginase activity and arginase 2 expression but reduced active p-eNOS(Ser1177) and NO levels in BAEC. In addition, both VEGF protein levels and endothelial elongation and network formation were reduced with continued hypoxia, whereas ROS levels increased and NO levels decreased. Arginase inhibition limited ROS, restored NO formation and VEGF expression, and prevented the reduction of angiogenesis. These results suggest a fundamental role of arginase activity in regulating angiogenic function.

  16. Gamma-Glutamylcysteine Inhibits Oxidative Stress in Human Endothelial Cells

    DTIC Science & Technology

    2012-01-01

    γ-Glutamylcysteine inhibits oxidative stress in human endothelial cells Yukiko K. Nakamura a, Michael A. Dubick b, Stanley T. Omaye a,⁎ a Department...n f o Article history: Received 12 July 2011 Accepted 16 October 2011 Keywords: γ-Glutamylcysteine Glutathione Glutathione synthetase Oxidative stress...include reducing risks of oxidative stress-related injuries and diseases. The ob- jective of this studywas to investigate the efficacy of GGC on GSH

  17. Endothelial proteoglycans inhibit bFGF binding and mitogenesis.

    PubMed

    Forsten, K E; Courant, N A; Nugent, M A

    1997-08-01

    Basic fibroblast growth factor (bFGF) is a known mitogen for vascular smooth muscle cells and has been implicated as having a role in a number of proliferative vascular disorders. Binding of bFGF to heparin or heparan sulfate has been demonstrated to both stimulate and inhibit growth factor activity. The activity, towards bFGF, of heparan sulfate proteoglycans present within the vascular system is likely related to the chemical characteristics of the glycosaminoglycan as well as the structure and pericellular location of the intact proteoglycans. We have previously shown that endothelial conditioned medium inhibits both bFGF binding to vascular smooth muscle cells and bFGF stimulated cell proliferation in vitro. In the present study, we have isolated proteoglycans from endothelial cell conditioned medium and demonstrated that they are responsible for the bFGF inhibitory activity. We further separated endothelial secreted proteoglycans into two fractions, PG-A and PG-B. The large sized fraction (PG-A) had greater inhibitory activity than did PG-B for both bFGF binding and bFGF stimulation of vascular smooth muscle cell proliferation. The increased relative activity of PG-A was attributed, in part, to larger heparan sulfate chains which were more potent inhibitors of bFGF binding than the smaller heparan sulfate chains on PG-B. Both proteoglycan fractions contained perlecan-like core proteins; however, PG-A contained an additional core protein (approximately 190 kDa) that was not observed in PG-B. Both proteoglycan fractions bound bFGF directly, and PG-A bound a significantly greater relative amount of bFGF than did PG-B. Thus the ability of endothelial heparan sulfate proteoglycans to bind bFGF and prevent its association with vascular smooth muscle cells appears essential for inhibition of bFGF-induced mitogenesis. The production of potent bFGF inhibitory heparan sulfate proteoglycans by endothelial cells might contribute to the maintenance of vascular homeostasis.

  18. Homocysteine injures vascular endothelial cells by inhibiting mitochondrial activity

    PubMed Central

    Yang, Fengyong; Qi, Xiujing; Gao, Zheng; Yang, Xingju; Zheng, Xingfeng; Duan, Chonghao; Zheng, Jian

    2016-01-01

    The aim of the present study was to investigate the role of homocysteine (Hcy) in the pathogenesis of pulmonary embolism (PE) and the associated molecular mechanisms in human umbilical vein endothelial cells (HUVECs). Hcy contents were detected with high-performance liquid chromatography. Apoptosis was detected by flow cytometry using Annexin-V staining. Cytochrome c oxidase (COX) activity was assessed with an enzyme activity assay, and the expression levels of COX 17 were determined by western blot analysis. Intracellular reactive oxygen species levels were measured using a microplate reader with a fluorescence probe. The results demonstrated that, compared with the control group, the serum Hcy levels were significantly elevated in the PE group, suggesting that Hcy may be an indicator for PE. Following treatment with Hcy, the apoptosis rate was markedly elevated in HUVECs. Moreover, Hcy decreased COX activity and downregulated the expression of COX 17 in HUVECs. Furthermore, Hcy increased the ROS levels in these endothelial cells. However, all the above-mentioned physiopathological changes induced by Hcy in HUVECs could be restored by folic acid. In conclusion, the results of the present study demonstrated that Hcy inhibited COX activity, downregulated COX 17 expression, increased intracellular ROS levels and enhanced apoptosis in endothelial cells. PMID:27698720

  19. Chlorine Gas Exposure Causes Systemic Endothelial Dysfunction by Inhibiting Endothelial Nitric Oxide Synthase–Dependent Signaling

    PubMed Central

    Honavar, Jaideep; Samal, Andrey A.; Bradley, Kelley M.; Brandon, Angela; Balanay, Joann; Squadrito, Giuseppe L.; MohanKumar, Krishnan; Maheshwari, Akhil; Postlethwait, Edward M.; Matalon, Sadis; Patel, Rakesh P.

    2011-01-01

    Chlorine gas (Cl2) exposure during accidents or in the military setting results primarily in injury to the lungs. However, the potential for Cl2 exposure to promote injury to the systemic vasculature leading to compromised vascular function has not been studied. We hypothesized that Cl2 promotes extrapulmonary endothelial dysfunction characterized by a loss of endothelial nitric oxide synthase (eNOS)-derived signaling. Male Sprague Dawley rats were exposed to Cl2 for 30 minutes, and eNOS-dependent vasodilation of aorta as a function of Cl2 dose (0–400 ppm) and time after exposure (0–48 h) were determined. Exposure to Cl2 (250–400 ppm) significantly inhibited eNOS-dependent vasodilation (stimulated by acetycholine) at 24 to 48 hours after exposure without affecting constriction responses to phenylephrine or vasodilation responses to an NO donor, suggesting decreased NO formation. Consistent with this hypothesis, eNOS protein expression was significantly decreased (∼ 60%) in aorta isolated from Cl2–exposed versus air-exposed rats. Moreover, inducible nitric oxide synthase (iNOS) mRNA was up-regulated in circulating leukocytes and aorta isolated 24 hours after Cl2 exposure, suggesting stimulation of inflammation in the systemic vasculature. Despite decreased eNOS expression and activity, no changes in mean arterial blood pressure were observed. However, injection of 1400W, a selective inhibitor of iNOS, increased mean arterial blood pressure only in Cl2–exposed animals, suggesting that iNOS-derived NO compensates for decreased eNOS-derived NO. These results highlight the potential for Cl2 exposure to promote postexposure systemic endothelial dysfunction via disruption of vascular NO homeostasis mechanisms. PMID:21131444

  20. Vascular endothelial-derived semaphorin 3 inhibits sympathetic axon growth.

    PubMed

    Damon, Deborah H

    2006-03-01

    Vascular sympathetic innervation is an important determinant of blood pressure and blood flow. The mechanisms that determine vascular sympathetic innervation are not well understood. Recent studies indicate that vascular endothelial cells (EC) express semaphorin 3A, a repulsive axon guidance cue. This suggests that EC would inhibit the growth of axons to blood vessels. The present study tests this hypothesis. RT-PCR and Western analyses confirmed that rat aortic vascular ECs expressed semaphorin 3A as well as other class 3 semaphorins (sema 3s). To determine the effects of EC-derived sema 3 on sympathetic axons, axon outgrowth was assessed in cultures of neonatal sympathetic ganglia grown for 72 h in the absence and presence of vascular EC. Nerve growth factor-induced axon growth in the presence of ECs was 50 +/- 4% (P < 0.05) of growth in the absence of ECs. ECs did not inhibit axon growth in the presence of an antibody that neutralized the activity of sema 3 (P > 0.05). RT-PCR and Western analyses also indicated that sema 3s were expressed in ECs of intact arteries. To assess the function of sema 3s in arteries, sympathetic ganglia were grown in the presence of arteries for 72 h, and the percentage of axons that grew toward the artery was determined: 44 +/- 4% of axons grew toward neonatal carotid arteries. Neutralization of sema 3s or removal of EC increased the percentage of axons that grew toward the artery (71 +/- 8% and 72 +/- 8%, respectively). These data indicate that vascular EC-derived sema 3s inhibit sympathetic axon growth and may thus be a determinant of vascular sympathetic innervation.

  1. Salidroside inhibits endogenous hydrogen peroxide induced cytotoxicity of endothelial cells.

    PubMed

    Zhao, Xingyu; Jin, Lianhai; Shen, Nan; Xu, Bin; Zhang, Wei; Zhu, Hongli; Luo, Zhengli

    2013-01-01

    Salidroside, a phenylpropanoid glycoside isolated from Rhodiola rosea L., shows potent antioxidant property. Herein, we investigated the protective effects of salidroside against hydrogen peroxide (H2O2)-induced oxidative damage in human endothelial cells (EVC-304). EVC-304 cells were incubated in the presence or absence of low steady states of H2O2 (3-4 µM) generated by glucose oxidase (GOX) with or without salidroside. 3(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione (GSH) assays were performed, together with Hoechst 33258 staining and flow cytometric analysis using Annexin-V and propidium iodide (PI) label. The results indicated that salidroside pretreatment attenuated endogenous H2O2 induced apoptotic cell death in EVC-304 cells in a dose-dependent pattern. Furthermore, Western blot data revealed that salidroside inhibited activation of caspase-3, 9 and cleavage of poly(ADP-ribose) polymerase (PARP) induced by endogenous H2O2. It also decreased the expression of Bax and rescued the balance of pro- and anti-apoptotic proteins. All these results demonstrated that salidroside may present a potential therapy for oxidative stress in cardiovascular and cerebrovascular diseases.

  2. Inhibition of endothelial lipase activity by sphingomyelin in the lipoproteins

    PubMed Central

    Yang, Peng; Belikova, Natalia A.; Billheimer, Jeff; Rader, Daniel J.; Hill, John S.; Subbaiah, Papasani V.

    2014-01-01

    Endothelial lipase (EL) is a major determinant of plasma HDL concentration, its activity being inversely proportional to HDL levels. Although it is known that it preferentially acts on HDL, compared to LDL and VLDL, the basis for this specificity is not known. Here we tested the hypothesis that sphingomyelin, a major phospholipid in lipoproteins is a physiological inhibitor of EL, and that the preference of the enzyme for HDL may be due to low sphingomyelin/ phosphatidylcholine (PtdCho) ratio in HDL, compared to other lipoproteins. Using recombinant human EL, we showed that sphingomyelin inhibits the hydrolysis of PtdCho in the liposomes in a concentration-dependent manner. While the enzyme showed lower hydrolysis of LDL PtdCho, compared to HDL PtdCho, this difference disappeared after the degradation of lipoprotein sphingomyelin by bacterial sphingomyelinase. Analysis of molecular species of PtdCho hydrolyzed by EL in the lipoproteins showed that the enzyme preferentially hydrolyzed PtdCho containing polyunsaturated fatty acids (PUFA) such as 22:6, 20:5, 20:4 at sn-2 position, generating the corresponding PUFA-lyso PtdCho. This specificity for PUFA-PtdCho species was not observed after depletion of sphingomyelin by sphingomyelinase. These results show that sphingomyelin not only plays a role in regulating EL activity, but also influences its specificity towards PtdCho species. PMID:25167836

  3. Inhibition of endothelial lipase activity by sphingomyelin in the lipoproteins.

    PubMed

    Yang, Peng; Belikova, Natalia A; Billheimer, Jeff; Rader, Daniel J; Hill, John S; Subbaiah, Papasani V

    2014-10-01

    Endothelial lipase (EL) is a major determinant of plasma HDL concentration, its activity being inversely proportional to HDL levels. Although it is known that it preferentially acts on HDL compared to LDL and VLDL, the basis for this specificity is not known. Here we tested the hypothesis that sphingomyelin, a major phospholipid in lipoproteins is a physiological inhibitor of EL, and that the preference of the enzyme for HDL may be due to low sphingomyelin/phosphatidylcholine (PtdCho) ratio in HDL, compared to other lipoproteins. Using recombinant human EL, we showed that sphingomyelin inhibits the hydrolysis of PtdCho in the liposomes in a concentration-dependent manner. While the enzyme showed lower hydrolysis of LDL PtdCho, compared to HDL PtdCho, this difference disappeared after the degradation of lipoprotein sphingomyelin by bacterial sphingomyelinase. Analysis of molecular species of PtdCho hydrolyzed by EL in the lipoproteins showed that the enzyme preferentially hydrolyzed PtdCho containing polyunsaturated fatty acids (PUFA) such as 22:6, 20:5, 20:4 at the sn-2 position, generating the corresponding PUFA-lyso PtdCho. This specificity for PUFA-PtdCho species was not observed after depletion of sphingomyelin by sphingomyelinase. These results show that sphingomyelin not only plays a role in regulating EL activity, but also influences its specificity towards PtdCho species.

  4. Asiaticoside Inhibits TNF-α-Induced Endothelial Hyperpermeability of Human Aortic Endothelial Cells.

    PubMed

    Fong, Lai Yen; Ng, Chin Theng; Zakaria, Zainul Amiruddin; Baharuldin, Mohamad Taufik Hidayat; Arifah, Abdul Kadir; Hakim, Muhammad Nazrul; Zuraini, Ahmad

    2015-10-01

    The increase in endothelial permeability often promotes edema formation in various pathological conditions. Tumor necrosis factor-alpha (TNF-α), a pro-atherogenic cytokine, impairs endothelial barrier function and causes endothelial dysfunction in early stage of atherosclerosis. Asiaticoside, one of the triterpenoids derived from Centella asiatica, is known to possess antiinflammatory activity. In order to examine the role of asiaticoside in preserving the endothelial barrier, we assessed its effects on endothelial hyperpermeability and disruption of actin filaments evoked by TNF-α in human aortic endothelial cells (HAEC). TNF-α caused an increase in endothelial permeability to fluorescein isothiocyanate (FITC)-dextran. Asiaticoside pretreatment significantly suppressed TNF-α-induced increased permeability. Asiaticoside also prevented TNF-α-induced actin redistribution by suppressing stress fiber formation. However, the increased F to G actin ratio stimulated by TNF-α was not changed by asiaticoside. Cytochalasin D, an actin depolymerizing agent, was used to correlate the anti-hyperpermeability effect of asiaticoside with actin cytoskeleton. Surprisingly, asiaticoside failed to prevent cytochalasin D-induced increased permeability. These results suggest that asiaticoside protects against the disruption of endothelial barrier and actin rearrangement triggered by TNF-α without a significant change in total actin pool. However, asiaticoside seems to work by other mechanisms to maintain the integrity of endothelial barrier rather than stabilizing the F-actin organization.

  5. An Antagonistic Vascular Endothelial Growth Factor (VEGF) Variant Inhibits VEGF-Stimulated Receptor Autophosphorylation and Proliferation of Human Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Siemeister, Gerhard; Schirner, Michael; Reusch, Petra; Barleon, Bernhard; Marme, Dieter; Martiny-Baron, Georg

    1998-04-01

    Vascular endothelial growth factor (VEGF) is a potent mitogen with a unique specificity for endothelial cells and a key mediator of aberrant endothelial cell proliferation and vascular permeability in a variety of human pathological situations, such as tumor angiogenesis, diabetic retinopathy, rheumatoid arthritis, or psoriasis. VEGF is a symmetric homodimeric molecule with two receptor binding interfaces lying on each pole of the molecule. Herein we report on the construction and recombinant expression of an asymmetric heterodimeric VEGF variant with an intact receptor binding interface at one pole and a mutant receptor binding interface at the second pole of the dimer. This VEGF variant binds to VEGF receptors but fails to induce receptor activation. In competition experiments, the heterodimeric VEGF variant antagonizes VEGF-stimulated receptor autophosphorylation and proliferation of endothelial cells. A 15-fold excess of the heterodimer was sufficient to inhibit VEGF-stimulated endothelial cell proliferation by 50%, and a 100-fold excess resulted in an almost complete inhibition. By using a rational approach that is based on the structure of VEGF, we have shown the feasibility to construct a VEGF variant that acts as an VEGF antagonist.

  6. Activation of AMP-Activated Protein Kinase Inhibits the Proliferation of Human Endothelial Cells

    PubMed Central

    Peyton, Kelly J.; Liu, Xiao-ming; Yu, Yajie; Yates, Benjamin

    2012-01-01

    AMP-activated protein kinase (AMPK) is an evolutionary conserved energy-sensing enzyme that regulates cell metabolism. Emerging evidence indicates that AMPK also plays an important role in modulating endothelial cell function. In the present study, we investigated whether AMPK modulates endothelial cell growth. Treatment of cultured human umbilical vein endothelial cells with the AMPK activators 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR), 6,7-dihydro-4-hydroxy-3-(2′-hydroxy[1,1′-biphenyl]-4-yl)-6-oxo-thieno[2,3-b]pyridine-5-carbonitrile (A-769662), or metformin inhibited cell proliferation and DNA synthesis. The antiproliferative action of AICAR was largely prevented by the adenosine kinase inhibitor 5′-iodotubercidin and mimicked by infecting endothelial cells with an adenovirus expressing constitutively active AMPK. In contrast, pharmacological blockade of endothelial nitric oxide synthase or heme oxygenase-1 activity failed to reverse the inhibition of endothelial cell growth by AICAR. Flow cytometry experiments revealed that pharmacological activation of AMPK arrested endothelial cells in the G0/G1 phase of the cell cycle, and this was associated with increases in p53 phosphorylation and p53, p21, and p27 protein expression and decreases in cyclin A protein expression and retinoblastoma protein phosphorylation. In addition, silencing p21 and p27 expression partially restored the mitogenic response of AMPK-activated cells. Finally, activation of AMPK by AICAR blocked the migration of endothelial cells after scrape injury and stimulated tube formation by endothelial cells plated onto Matrigel-coated plates. In conclusion, these studies demonstrate that AMPK activation inhibits endothelial cell proliferation by elevating p21 and p27 expression. In addition, they show that AMPK regulates endothelial cell migration and differentiation and identify AMPK as an attractive therapeutic target in treating diseases associated with aberrant

  7. Delta- and gamma-tocotrienol isomers are potent in inhibiting inflammation and endothelial activation in stimulated human endothelial cells

    PubMed Central

    Muid, Suhaila; Froemming, Gabriele R. Anisah; Rahman, Thuhairah; Ali, A. Manaf; Nawawi, Hapizah M.

    2016-01-01

    Background Tocotrienols (TCTs) are more potent antioxidants than α-tocopherol (TOC). However, the effectiveness and mechanism of the action of TCT isomers as anti-atherosclerotic agents in stimulated human endothelial cells under inflammatory conditions are not well established. Aims 1) To compare the effects of different TCT isomers on inflammation, endothelial activation, and endothelial nitric oxide synthase (eNOS). 2) To identify the two most potent TCT isomers in stimulated human endothelial cells. 3) To investigate the effects of TCT isomers on NFκB activation, and protein and gene expression levels in stimulated human endothelial cells. Methods Human umbilical vein endothelial cells were incubated with various concentrations of TCT isomers or α-TOC (0.3–10 µM), together with lipopolysaccharides for 16 h. Supernatant cells were collected and measured for protein and gene expression of cytokines (interleukin-6, or IL-6; tumor necrosis factor-alpha, or TNF-α), adhesion molecules (intercellular cell adhesion molecule-1, or ICAM-1; vascular cell adhesion molecule-1, or VCAM-1; and e-selectin), eNOS, and NFκB. Results δ-TCT is the most potent TCT isomer in the inhibition of IL-6, ICAM-1, VCAM-1, and NFκB, and it is the second potent in inhibiting e-selectin and eNOS. γ-TCT isomer is the most potent isomer in inhibiting e-selectin and eNOS, and it is the second most potent in inhibiting is IL-6, VCAM-1, and NFκB. For ICAM-1 protein expression, the most potent is δ-TCT followed by α-TCT. α- and β-TCT inhibit IL-6 at the highest concentration (10 µM) but enhance IL-6 at lower concentrations. γ-TCT markedly increases eNOS expression by 8–11-fold at higher concentrations (5–10 µM) but exhibits neutral effects at lower concentrations. Conclusion δ- and γ-TCT are the two most potent TCT isomers in terms of the inhibition of inflammation and endothelial activation whilst enhancing eNOS, possibly mediated via the NFκB pathway. Hence, there is a

  8. Endothelin-2 signaling in the neural retina promotes the endothelial tip cell state and inhibits angiogenesis

    PubMed Central

    Rattner, Amir; Yu, Huimin; Williams, John; Smallwood, Philip M.; Nathans, Jeremy

    2013-01-01

    Endothelin signaling is required for neural crest migration and homeostatic regulation of blood pressure. Here, we report that constitutive overexpression of Endothelin-2 (Edn2) in the mouse retina perturbs vascular development by inhibiting endothelial cell migration across the retinal surface and subsequent endothelial cell invasion into the retina. Developing endothelial cells exist in one of two states: tip cells at the growing front and stalk cells in the vascular plexus behind the front. This division of endothelial cell states is one of the central organizing principles of angiogenesis. In the developing retina, Edn2 overexpression leads to overproduction of endothelial tip cells by both morphologic and molecular criteria. Spatially localized overexpression of Edn2 produces a correspondingly localized endothelial response. Edn2 overexpression in the early embryo inhibits vascular development at midgestation, but Edn2 overexpression in developing skin and brain has no discernible effect on vascular structure. Inhibition of retinal angiogenesis by Edn2 requires expression of Endothelin receptor A but not Endothelin receptor B in the neural retina. Taken together, these observations imply that the neural retina responds to Edn2 by synthesizing one or more factors that promote the endothelial tip cell state and inhibit angiogenesis. The response to Edn2 is sufficiently potent that it overrides the activities of other homeostatic regulators of angiogenesis, such as Vegf. PMID:24043815

  9. Ozone inhibits endothelial cell cyclooxygenase activity through formation of hydrogen peroxide.

    PubMed

    Madden, M C; Eling, T E; Friedman, M

    1987-09-01

    We have previously demonstrated that a 2H exposure of cultured pulmonary endothelial cells to ozone (0.0-1.0 ppm) in-vitro resulted in a concentration-dependent reduction of endothelial prostacyclin production (90% decrease at the 1.0 ppm level). Ozone-exposed endothelial cells, incubated with 20 uM arachidonate, also demonstrated a significant inhibition of prostacyclin synthesis. To further examine the mechanisms of the inhibition of prostacyclin synthesis, bovine pulmonary endothelial cells were exposed to 1.0 ppm ozone for 2H. A significant decrease in prostacyclin synthesis was found within 5 min of exposure (77 +/- 36% of air-exposed control values, p less than 0.05). Endothelial prostacyclin synthesis returned to baseline levels by 12H after ozone exposure, a time point which was similar to the recovery time of unexposed endothelium treated with 0.5 uM acetylsalicylic acid. Incubation of endothelial cells, previously exposed to 1.0 ppm ozone for 2 hours, with 4 uM PGH2 resulted in restoration of essentially normal prostacyclin synthesis. When endothelial cells were co-incubated with catalase (5 U/ml) during ozone exposure, no inhibition of prostacyclin synthesis was observed. Co-incubation with either heat-inactivated catalase or superoxide dismutase (10 U/ml) did not affect the ozone-induced inhibition of prostacyclin synthesis. These data suggest that H2O2 is a major toxic species produced in endothelial cells during ozone exposure and responsible for the inhibition of endothelial cyclooxygenase activity.

  10. Ozone inhibits endothelial cell cyclooxygenase activity through formation of hydrogen peroxide

    SciTech Connect

    Madden, M.C.; Eling, T.E.; Friedman, M.

    1987-09-01

    We have previously demonstrated that a 2H exposure of cultured pulmonary endothelial cells to ozone (0.0-1.0 ppm) in-vitro resulted in a concentration-dependent reduction of endothelial prostacyclin production (90% decrease at the 1.0 ppm level). Ozone-exposed endothelial cells, incubated with 20 uM arachidonate, also demonstrated a significant inhibition of prostacyclin synthesis. To further examine the mechanisms of the inhibition of prostacyclin synthesis, bovine pulmonary endothelial cells were exposed to 1.0 ppm ozone for 2H. A significant decrease in prostacyclin synthesis was found within 5 min of exposure (77 +/- 36% of air-exposed control values, p less than 0.05). Endothelial prostacyclin synthesis returned to baseline levels by 12H after ozone exposure, a time point which was similar to the recovery time of unexposed endothelium treated with 0.5 uM acetylsalicylic acid. Incubation of endothelial cells, previously exposed to 1.0 ppm ozone for 2 hours, with 4 uM PGH2 resulted in restoration of essentially normal prostacyclin synthesis. When endothelial cells were co-incubated with catalase (5 U/ml) during ozone exposure, no inhibition of prostacyclin synthesis was observed. Co-incubation with either heat-inactivated catalase or superoxide dismutase (10 U/ml) did not affect the ozone-induced inhibition of prostacyclin synthesis. These data suggest that H/sub 2/O/sub 2/ is a major toxic species produced in endothelial cells during ozone exposure and responsible for the inhibition of endothelial cyclooxygenase activity.

  11. Endothelial repair in stented arteries is accelerated by inhibition of Rho-associated protein kinase

    PubMed Central

    Hsiao, Sarah T.; Spencer, Tim; Boldock, Luke; Prosseda, Svenja Dannewitz; Xanthis, Ioannis; Tovar-Lopez, Francesco J.; Van Beusekom, Heleen M. M.; Khamis, Ramzi Y; Foin, Nicolas; Bowden, Neil; Hussain, Adil; Rothman, Alex; Ridger, Victoria; Halliday, Ian; Perrault, Cecile; Gunn, Julian; Evans, Paul C.

    2016-01-01

    Aims Stent deployment causes endothelial cells (EC) denudation, which promotes in-stent restenosis and thrombosis. Thus endothelial regrowth in stented arteries is an important therapeutic goal. Stent struts modify local hemodynamics, however the effects of flow perturbation on EC injury and repair are incompletely understood. By studying the effects of stent struts on flow and EC migration, we identified an intervention that promotes endothelial repair in stented arteries. Methods and Results In vitro and in vivo models were developed to monitor endothelialization under flow and the influence of stent struts. A 2D parallel-plate flow chamber with 100 μm ridges arranged perpendicular to the flow was used. Live cell imaging coupled to computational fluid dynamic simulations revealed that EC migrate in the direction of flow upstream from the ridges but subsequently accumulate downstream from ridges at sites of bidirectional flow. The mechanism of EC trapping by bidirectional flow involved reduced migratory polarity associated with altered actin dynamics. Inhibition of Rho-associated protein kinase (ROCK) enhanced endothelialization of ridged surfaces by promoting migratory polarity under bidirectional flow (P < 0.01). To more closely mimic the in vivo situation, we cultured EC on the inner surface of polydimethylsiloxane tubing containing Coroflex Blue stents (65 μm struts) and monitored migration. ROCK inhibition significantly enhanced EC accumulation downstream from struts under flow (P < 0.05). We investigated the effects of ROCK inhibition on re-endothelialization in vivo using a porcine model of EC denudation and stent placement. En face staining and confocal microscopy revealed that inhibition of ROCK using fasudil (30 mg/day via osmotic minipump) significantly increased re-endothelialization of stented carotid arteries (P < 0.05). Conclusions Stent struts delay endothelial repair by generating localized bidirectional flow which traps migrating EC. ROCK

  12. Endothelial repair in stented arteries is accelerated by inhibition of Rho-associated protein kinase.

    PubMed

    Hsiao, Sarah T; Spencer, Tim; Boldock, Luke; Prosseda, Svenja Dannewitz; Xanthis, Ioannis; Tovar-Lopez, Francesco J; Van Beusekom, Heleen M M; Khamis, Ramzi Y; Foin, Nicolas; Bowden, Neil; Hussain, Adil; Rothman, Alex; Ridger, Victoria; Halliday, Ian; Perrault, Cecile; Gunn, Julian; Evans, Paul C

    2016-12-01

    Stent deployment causes endothelial cells (EC) denudation, which promotes in-stent restenosis and thrombosis. Thus endothelial regrowth in stented arteries is an important therapeutic goal. Stent struts modify local hemodynamics, however the effects of flow perturbation on EC injury and repair are incompletely understood. By studying the effects of stent struts on flow and EC migration, we identified an intervention that promotes endothelial repair in stented arteries. In vitro and in vivo models were developed to monitor endothelialization under flow and the influence of stent struts. A 2D parallel-plate flow chamber with 100 μm ridges arranged perpendicular to the flow was used. Live cell imaging coupled to computational fluid dynamic simulations revealed that EC migrate in the direction of flow upstream from the ridges but subsequently accumulate downstream from ridges at sites of bidirectional flow. The mechanism of EC trapping by bidirectional flow involved reduced migratory polarity associated with altered actin dynamics. Inhibition of Rho-associated protein kinase (ROCK) enhanced endothelialization of ridged surfaces by promoting migratory polarity under bidirectional flow (P < 0.01). To more closely mimic the in vivo situation, we cultured EC on the inner surface of polydimethylsiloxane tubing containing Coroflex Blue stents (65 μm struts) and monitored migration. ROCK inhibition significantly enhanced EC accumulation downstream from struts under flow (P < 0.05). We investigated the effects of ROCK inhibition on re-endothelialization in vivo using a porcine model of EC denudation and stent placement. En face staining and confocal microscopy revealed that inhibition of ROCK using fasudil (30 mg/day via osmotic minipump) significantly increased re-endothelialization of stented carotid arteries (P < 0.05). Stent struts delay endothelial repair by generating localized bidirectional flow which traps migrating EC. ROCK inhibitors accelerate endothelial repair

  13. Imeglimin prevents human endothelial cell death by inhibiting mitochondrial permeability transition without inhibiting mitochondrial respiration

    PubMed Central

    Detaille, D; Vial, G; Borel, A-L; Cottet-Rouselle, C; Hallakou-Bozec, S; Bolze, S; Fouqueray, P; Fontaine, E

    2016-01-01

    Imeglimin is the first in a new class of oral glucose-lowering agents, having recently completed its phase 2b trial. As Imeglimin did show a full prevention of β-cell apoptosis, and since angiopathy represents a major complication of diabetes, we studied Imeglimin protective effects on hyperglycemia-induced death of human endothelial cells (HMEC-1). These cells were incubated in several oxidative stress environments (exposure to high glucose and oxidizing agent tert-butylhydroperoxide) which led to mitochondrial permeability transition pore (PTP) opening, cytochrome c release and cell death. These events were fully prevented by Imeglimin treatment. This protective effect on cell death occurred without any effect on oxygen consumption rate, on lactate production and on cytosolic redox or phosphate potentials. Imeglimin also dramatically decreased reactive oxygen species production, inhibiting specifically reverse electron transfer through complex I. We conclude that Imeglimin prevents hyperglycemia-induced cell death in HMEC-1 through inhibition of PTP opening without inhibiting mitochondrial respiration nor affecting cellular energy status. Considering the high prevalence of macrovascular and microvascular complications in type 2 diabetic subjects, these results together suggest a potential benefit of Imeglimin in diabetic angiopathy. PMID:27551496

  14. Inhibition of astroglia-induced endothelial differentiation by inorganic lead: a role for protein kinase C.

    PubMed Central

    Laterra, J; Bressler, J P; Indurti, R R; Belloni-Olivi, L; Goldstein, G W

    1992-01-01

    Microvascular endothelial function in developing brain is particularly sensitive to lead toxicity, and it has been hypothesized that this results from the modulation of protein kinase C (PKC) by lead. We examined the effects of inorganic lead on an in vitro model of central nervous system endothelial differentiation in which astroglial cells induce central nervous system endothelial cells to form capillary-like structures. Capillary-like structure formation within C6 astroglial-endothelial cocultures was inhibited by lead acetate with 50% maximal inhibition at 0.5 microM total lead. Inhibition was independent of effects on cell viability or growth. Under conditions that inhibited capillary-like structure formation, we found that lead increased membrane-associated PKC in both C6 astroglial and endothelial cells. Prolonged exposure of C6 cells to 5 microM lead for up to 16 h resulted in a time-dependent increase in membranous PKC as determined by immunoblot analysis. Membranous PKC increased after 5-h exposures to as little as 50 nM lead and was maximal at approximately 1 microM. Phorbol esters were used to determine whether PKC modulation was causally related to the inhibition of endothelial differentiation by lead. Phorbol 12-myristate 13-acetate (10 nM) inhibited capillary-like structure formation by 65 +/- 5%, whereas 4 alpha-phorbol 12,13-didecanoate was without effect. These findings suggest that inorganic lead induces cerebral microvessel dysfunction by interfering with PKC modulation in microvascular endothelial or perivascular astroglial cells. Images PMID:1438272

  15. Conditioned Media from Microvascular Endothelial Cells Cultured in Simulated Microgravity Inhibit Osteoblast Activity

    PubMed Central

    Cazzaniga, Alessandra; Castiglioni, Sara; Maier, Jeanette A. M.

    2014-01-01

    Background and Aims. Gravity contributes to the maintenance of bone integrity. Accordingly, weightlessness conditions during space flight accelerate bone loss and experimental models in real and simulated microgravity show decreased osteoblastic and increased osteoclastic activities. It is well known that the endothelium and bone cells cross-talk and this intercellular communication is vital to regulate bone homeostasis. Because microgravity promotes microvascular endothelial dysfunction, we anticipated that the molecular cross-talk between endothelial cells exposed to simulated microgravity and osteoblasts might be altered. Results. We cultured human microvascular endothelial cells in simulated microgravity using the rotating wall vessel device developed by NASA. Endothelial cells in microgravity show growth inhibition and release higher amounts of matrix metalloproteases type 2 and interleukin-6 than controls. Conditioned media collected from microvascular endothelial cells in simulated microgravity were used to culture human osteoblasts and were shown to retard osteoblast proliferation and inhibit their activity. Discussion. Microvascular endothelial cells in microgravity are growth retarded and release high amounts of matrix metalloproteases type 2 and interleukin-6, which might play a role in retarding the growth of osteoblasts and impairing their osteogenic activity. Conclusions. We demonstrate that since simulated microgravity modulates microvascular endothelial cell function, it indirectly impairs osteoblastic function. PMID:25210716

  16. Interferon-alpha and dexamethasone inhibit adhesion of T cells to endothelial cells and synovial cells

    PubMed Central

    Eguchi, K.; Kawakami, A.; Nakashima, M.; Ida, H.; Sakito, S.; Matsuoka, N.; Terada, K.; Sakai, M.; Kawabe, Y.; Fukuda, T.; Ishimaru, T.; Kurouji, K.; Fujita, N.; Aoyagi, T.; Maeda, K.; Nagataki, S.

    1992-01-01

    We investigated whether interferon-gamma (IFN-γ), interferon-alpha (IFN-α) and glucocorticoids affected the adhesion of T cells to human umbilical endothelial cells or human synovial cells. About 30% of peripheral blood T cells could bind to unstimulated endothelial cells, but only a few T cells could bind to unstimulated synovial cells. When both endothelial cells and synovial cells were cultured with recombinant IFN-γ (rIFN-γ), the percentage of T cell binding to both types of cells increased in a dose-dependent manner. rIFN-α and dexamethasone blocked the T cell binding to unstimulated endothelial cells. Furthermore, rIFN-α and dexamethasone suppressed T cell binding to both endothelial cells and synovial cells stimulated by IFN-γ, and also inhibited intercellular adhesion molecule-1 (ICAM-1) expression on both endothelial cells and synovial cells stimulated by IFN-γ. These results suggest that IFN-α and glucocorticoids may inhibit T cell binding to endothelial cells or synovial cells by modulating adhesion molecule expression on these cells. PMID:1606729

  17. Ascorbate inhibits NADPH oxidase subunit p47phox expression in microvascular endothelial cells.

    PubMed

    Wu, Feng; Schuster, David P; Tyml, Karel; Wilson, John X

    2007-01-01

    The production of reactive oxygen species (ROS) is central to the etiology of endothelial dysfunction in sepsis. Endothelial cells respond to infection by activating NADPH oxidases that are sources of intracellular ROS and potential targets for therapeutic administration of antioxidants. Ascorbate is an antioxidant that accumulates in these cells and improves capillary blood flow, vascular reactivity, arterial blood pressure, and survival in experimental sepsis. Therefore, the present study tested the hypothesis that ascorbate regulates NADPH oxidases in microvascular endothelial cells exposed to septic insult. We observed that incubation with Escherichia coli lipopolysaccharide (LPS) and interferon-gamma (IFNgamma) increased NADPH oxidase activity and expression of the enzyme subunit p47phox in mouse microvascular endothelial cells of skeletal muscle origin. Pretreatment of the cells with ascorbate prevented these increases. Polyethylene glycol-conjugated catalase and selective inhibitors of Jak2 also abrogated induction of p47phox. Exogenous hydrogen peroxide induced p47phox expression that was prevented by pretreatment of the cells with ascorbate. LPS+IFNgamma or hydrogen peroxide activated the Jak2/Stat1/IRF1 pathway and this effect was also inhibited by ascorbate. In conclusion, ascorbate blocks the stimulation by septic insult of redox-sensitive Jak2/Stat1/IRF1 signaling, p47phox expression, and NADPH oxidase activity in microvascular endothelial cells. Because endothelial NADPH oxidases produce ROS that can cause endothelial dysfunction, their inhibition by ascorbate may represent a new strategy for sepsis therapy.

  18. Syntaxin-binding protein STXBP5 inhibits endothelial exocytosis and promotes platelet secretion

    PubMed Central

    Zhu, Qiuyu; Yamakuchi, Munekazu; Ture, Sara; de la Luz Garcia-Hernandez, Maria; Ko, Kyung Ae; Modjeski, Kristina L.; LoMonaco, Michael B.; Johnson, Andrew D.; O’Donnell, Christopher J.; Takai, Yoshimi; Morrell, Craig N.; Lowenstein, Charles J.

    2014-01-01

    In humans, vWF levels predict the risk of myocardial infarction and thrombosis; however, the factors that influence vWF levels are not completely understood. Recent genome-wide association studies (GWAS) have identified syntaxin-binding protein 5 (STXBP5) as a candidate gene linked to changes in vWF plasma levels, though the functional relationship between STXBP5 and vWF is unknown. We hypothesized that STXBP5 inhibits endothelial cell exocytosis. We found that STXBP5 is expressed in human endothelial cells and colocalizes with and interacts with syntaxin 4. In human endothelial cells reduction of STXBP5 increased exocytosis of vWF and P-selectin. Mice lacking Stxbp5 had higher levels of vWF in the plasma, increased P-selectin translocation, and more platelet-endothelial interactions, which suggests that STXBP5 inhibits endothelial exocytosis. However, Stxbp5 KO mice also displayed hemostasis defects, including prolonged tail bleeding times and impaired mesenteric arteriole and carotid artery thrombosis. Furthermore, platelets from Stxbp5 KO mice had defects in platelet secretion and activation; thus, STXBP5 inhibits endothelial exocytosis but promotes platelet secretion. Our study reveals a vascular function for STXBP5, validates the functional relevance of a candidate gene identified by GWAS, and suggests that variation within STXBP5 is a genetic risk for venous thromboembolic disease. PMID:25244095

  19. Nafamostat Mesilate Inhibits TNF-α-Induced Vascular Endothelial Cell Dysfunction by Inhibiting Reactive Oxygen Species Production.

    PubMed

    Kang, Min-Woong; Song, Hee-Jung; Kang, Shin Kwang; Kim, Yonghwan; Jung, Saet-Byel; Jee, Sungju; Moon, Jae Young; Suh, Kwang-Sun; Lee, Sang Do; Jeon, Byeong Hwa; Kim, Cuk-Seong

    2015-05-01

    Nafamostat mesilate (NM) is a serine protease inhibitor with anticoagulant and anti-inflammatory effects. NM has been used in Asia for anticoagulation during extracorporeal circulation in patients undergoing continuous renal replacement therapy and extra corporeal membrane oxygenation. Oxidative stress is an independent risk factor for atherosclerotic vascular disease and is associated with vascular endothelial function. We investigated whether NM could inhibit endothelial dysfunction induced by tumor necrosis factor-α (TNF-α). Human umbilical vein endothelial cells (HUVECs) were treated with TNF-α for 24 h. The effects of NM on monocyte adhesion, vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1) protein expression, p38 mitogen-activated protein kinase (MAPK) activation, and intracellular superoxide production were then examined. NM (0.01~100 µg/mL) did not affect HUVEC viability; however, it inhibited the increases in reactive oxygen species (ROS) production and p66shc expression elicited by TNF-α (3 ng/mL), and it dose dependently prevented the TNF-α-induced upregulation of endothelial VCAM-1 and ICAM-1. In addition, it mitigated TNF-α-induced p38 MAPK phosphorylation and the adhesion of U937 monocytes. These data suggest that NM mitigates TNF-α-induced monocyte adhesion and the expression of endothelial cell adhesion molecules, and that the anti-adhesive effect of NM is mediated through the inhibition of p66shc, ROS production, and p38 MAPK activation.

  20. Cell-permeable iron inhibits vascular endothelial growth factor receptor-2 signaling and tumor angiogenesis

    PubMed Central

    Kir, Devika; Saluja, Manju; Modi, Shrey; Venkatachalam, Annapoorna; Schnettler, Erica; Roy, Sabita; Ramakrishnan, Sundaram

    2016-01-01

    Angiogenesis is important for tumor growth and metastasis. Hypoxia in tumors drives this angiogenic response by stabilizing Hypoxia Inducible Factors (HIF) and target genes like Vascular Endothelial Growth Factor (VEGF). HIF stability is regulated by Prolylhydroxylases (PHD)-mediated modification. Iron is an important cofactor in regulating the enzymatic activity of PHDs. Reducing intracellular iron, for instance, mimics hypoxia and induces a pro-angiogenic response. It is hypothesized that increasing the intracellular iron levels will have an opposite, anti-angiogenic effect. We tested this hypothesis by perturbing iron homeostasis in endothelial cells using a unique form of iron, Ferric Ammonium Citrate (FAC). FAC is a cell-permeable form of iron, which can passively enter into cells bypassing the transferrin receptor mediated uptake of transferrin-bound iron. Our studies show that FAC does not decrease the levels of HIF-1α and HIF-2α in endothelial cells but inhibits the autocrine stimulation of VEGF-Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) system by blocking receptor tyrosine kinase phosphorylation. FAC inhibits VEGF-induced endothelial cell proliferation, migration, tube formation and sprouting. Finally, systemic administration of FAC inhibits VEGF and tumor cell-induced angiogenesis in vivo. In conclusion, our studies show that cell-permeable iron attenuates VEGFR-2 mediated signaling and inhibits tumor angiogenesis. PMID:27589831

  1. Cell-permeable iron inhibits vascular endothelial growth factor receptor-2 signaling and tumor angiogenesis.

    PubMed

    Kir, Devika; Saluja, Manju; Modi, Shrey; Venkatachalam, Annapoorna; Schnettler, Erica; Roy, Sabita; Ramakrishnan, Sundaram

    2016-10-04

    Angiogenesis is important for tumor growth and metastasis. Hypoxia in tumors drives this angiogenic response by stabilizing Hypoxia Inducible Factors (HIF) and target genes like Vascular Endothelial Growth Factor (VEGF). HIF stability is regulated by Prolylhydroxylases (PHD)-mediated modification. Iron is an important cofactor in regulating the enzymatic activity of PHDs. Reducing intracellular iron, for instance, mimics hypoxia and induces a pro-angiogenic response. It is hypothesized that increasing the intracellular iron levels will have an opposite, anti-angiogenic effect. We tested this hypothesis by perturbing iron homeostasis in endothelial cells using a unique form of iron, Ferric Ammonium Citrate (FAC). FAC is a cell-permeable form of iron, which can passively enter into cells bypassing the transferrin receptor mediated uptake of transferrin-bound iron. Our studies show that FAC does not decrease the levels of HIF-1α and HIF-2α in endothelial cells but inhibits the autocrine stimulation of VEGF-Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) system by blocking receptor tyrosine kinase phosphorylation. FAC inhibits VEGF-induced endothelial cell proliferation, migration, tube formation and sprouting. Finally, systemic administration of FAC inhibits VEGF and tumor cell-induced angiogenesis in vivo. In conclusion, our studies show that cell-permeable iron attenuates VEGFR-2 mediated signaling and inhibits tumor angiogenesis.

  2. Allicin inhibits lymphangiogenesis through suppressing activation of vascular endothelial growth factor (VEGF) receptor.

    PubMed

    Wang, Weicang; Du, Zheyuan; Nimiya, Yoshiki; Sukamtoh, Elvira; Kim, Daeyoung; Zhang, Guodong

    2016-03-01

    Allicin, the most abundant organosulfur compound in freshly crushed garlic tissues, has been shown to have various health-promoting effects, including anticancer actions. A better understanding of the effects and mechanisms of allicin on tumorigenesis could facilitate development of allicin or garlic products for cancer prevention. Here we found that allicin inhibited lymphangiogenesis, which is a critical cellular process implicated in tumor metastasis. In primary human lymphatic endothelial cells, allicin at 10 μM inhibited capillary-like tube formation and cell migration, and it suppressed phosphorylation of vascular endothelial growth factor receptor 2 and focal adhesion kinase. Using a Matrigel plug assay in mice, addition of 10 μg allicin in Matrigel plug inhibited 40-50% of vascular endothelial growth factor-C-induced infiltration of lymphatic endothelial cells and leukocytes. S-Allylmercaptoglutathione, a major cellular metabolite of allicin, had no effect on lymphangiogenic responses in lymphatic endothelial cells. Together, these results demonstrate the antilymphangiogenic effect of allicin in vitro and in vivo, suggesting a novel mechanism for the health-promoting effects of garlic compounds.

  3. RhoB controls endothelial barrier recovery by inhibiting Rac1 trafficking to the cell border

    PubMed Central

    Marcos-Ramiro, Beatriz; García-Weber, Diego; Barroso, Susana; Feito, Jorge; Ortega, María C.; Cernuda-Morollón, Eva; Reglero-Real, Natalia; Fernández-Martín, Laura; Durán, Maria C.; Alonso, Miguel A.; Correas, Isabel; Cox, Susan; Ridley, Anne J.

    2016-01-01

    Endothelial barrier dysfunction underlies chronic inflammatory diseases. In searching for new proteins essential to the human endothelial inflammatory response, we have found that the endosomal GTPase RhoB is up-regulated in response to inflammatory cytokines and expressed in the endothelium of some chronically inflamed tissues. We show that although RhoB and the related RhoA and RhoC play additive and redundant roles in various aspects of endothelial barrier function, RhoB specifically inhibits barrier restoration after acute cell contraction by preventing plasma membrane extension. During barrier restoration, RhoB trafficking is induced between vesicles containing RhoB nanoclusters and plasma membrane protrusions. The Rho GTPase Rac1 controls membrane spreading and stabilizes endothelial barriers. We show that RhoB colocalizes with Rac1 in endosomes and inhibits Rac1 activity and trafficking to the cell border during barrier recovery. Inhibition of endosomal trafficking impairs barrier reformation, whereas induction of Rac1 translocation to the plasma membrane accelerates it. Therefore, RhoB-specific regulation of Rac1 trafficking controls endothelial barrier integrity during inflammation. PMID:27138256

  4. Targeting NCK-Mediated Endothelial Cell Front-Rear Polarity Inhibits Neo-Vascularization

    PubMed Central

    Dubrac, Alexandre; Genet, Gael; Ola, Roxana; Zhang, Feng; Pibouin-Fragner, Laurence; Han, Jinah; Zhang, Jiasheng; Thomas, Jean-Léon; Chedotal, Alain; Schwartz, Martin A.; Eichmann, Anne

    2015-01-01

    Background Sprouting angiogenesis is a key process driving blood vessel growth in ischemic tissues and an important drug target in a number of diseases, including wet macular degeneration and wound healing. Endothelial cells forming the sprout must develop front-rear polarity to allow sprout extension. The adaptor proteins Nck1 and 2 are known regulators of cytoskeletal dynamics and polarity, but their function in angiogenesis is poorly understood. Here we show that the Nck adaptors are required for endothelial cell front-rear polarity and migration downstream of the angiogenic growth factors VEGF-A and Slit2. Methods and Results Mice carrying inducible, endothelial-specific Nck1/2 deletions fail to develop front-rear polarized vessel sprouts and exhibit severe angiogenesis defects in the postnatal retina and during embryonic development. Inactivation of NCK1 and 2 inhibits polarity by preventing Cdc42 and Pak2 activation by VEGF-A and Slit2. Mechanistically, NCK binding to ROBO1 is required for both Slit2 and VEGF induced front-rear polarity. Selective inhibition of polarized endothelial cell migration by targeting Nck1/2 prevents hypersprouting induced by Notch or Bmp signaling inhibition, as well as pathological ocular neovascularization and wound healing. Conclusions These data reveal a novel signal integration mechanism involving NCK1/2, ROBO1/2 and VEGFR2 that controls endothelial cell front-rear polarity during sprouting angiogenesis. PMID:26659946

  5. Inhibition of TGF-β Signaling in SHED Enhances Endothelial Differentiation.

    PubMed

    Xu, J G; Gong, T; Wang, Y Y; Zou, T; Heng, B C; Yang, Y Q; Zhang, C F

    2017-10-01

    Low efficiency of deriving endothelial cells (ECs) from adult stem cells hampers their utilization in tissue engineering studies. The purpose of this study was to investigate whether suppression of transforming growth factor beta (TGF-β) signaling could enhance the differentiation efficiency of dental pulp-derived stem cells into ECs. We initially used vascular endothelial growth factor A (VEGF-A) to stimulate 2 dental pulp-derived stem cells (dental pulp stem cells and stem cells from human exfoliated deciduous teeth [SHED]) and compared their differentiation capacity into ECs. We further evaluated whether the vascular endothelial growth factor receptor I (VEGF-RI)-specific ligand placental growth factor-1 (PlGF-1) could mediate endothelial differentiation. Finally, we investigated whether the TGF-β signaling inhibitor SB-431542 could enhance the inductive effect of VEGF-A on endothelial differentiation, as well as the underlying mechanisms involved. ECs differentiated from dental pulp-derived stem cells exhibited the typical phenotypes of primary ECs, with SHED possessing a higher endothelial differentiation potential than dental pulp stem cells. VEGFR1-specific ligand-PLGF exerted a negligible effect on SHED-ECs differentiation. Compared with VEGF-A alone, the combination of VEGF-A and SB-431542 significantly enhanced the endothelial differentiation of SHED. The presence of SB-431542 inhibited the phosphorylation of Suppressor of Mothers Against Decapentaplegic 2/3 (SMAD2/3), allowing for VEGF-A-dependent phosphorylation and upregulation of VEGFR2. Our results indicate that the combination of VEGF-A and SB-431542 could enhance the differentiation of dental pulp-derived stem cells into endothelial cells, and this process is mediated through enhancement of VEGF-A-VEGFR2 signaling and concomitant inhibition of TGF-β-SMAD2/3 signaling.

  6. Propranolol inhibits endothelial progenitor cell homing: a possible treatment mechanism of infantile hemangioma.

    PubMed

    Zou, Hai-Xiao; Jia, Jun; Zhang, Wen-Feng; Sun, Zhi-Jun; Zhao, Yi-Fang

    2013-01-01

    Propranolol effectively treats infantile hemangioma, but its mechanisms of action remain poorly understood. Although the antiangiogenesis role of propranolol has been previously demonstrated, several lines of evidence suggest that this therapeutic agent may affect the neovascular formation in infantile hemangioma by targeting vasculogenesis. In addition, the homing of endothelial progenitor cells to the lesion of infantile hemangioma plays an important role during the process of vasculogenesis. The purpose of this study was to investigate whether propranolol inhibits the vasculogenesis in infantile hemangioma by targeting endothelial progenitor cells recruitment. Endothelial progenitor cells were treated with different concentrations (0, 1, 5, 10, 20, 40, 60, 80, 100 μM) of propranolol for indicated times (24, 48, 72 h). Cell proliferation and viability were assessed by MTT assay and trypan blue staining. Cell migration was determined by wound healing assay and Boyden chamber assay. The expression levels of extracellular signal regulated kinase, phospho-extracellular signal regulated kinase, Akt, and phospho-Akt were measured by Western blot analysis to explore the molecular mechanism of propranolol on endothelial progenitor cells. In addition, the expression of CXCR4 was measured by Western blot and reverse transcriptase polymerase chain reaction. Propranolol did not significantly affect the proliferation of endothelial progenitor cells. It inhibited stromal-cell-derived factor 1α-induced migration of endothelial progenitor cells through the Akt and MAPK pathways and the expression of CXCR4 in a dose- and time-dependent manner. In addition, the expression of CXCR4 was suppressed by propranolol most likely through the Akt and MAPK pathways. Propranolol inhibits stromal-cell-derived factor 1α-induced endothelial progenitor cell homing by suppressing the expression of CXCR4 most likely through the Akt and MAPK pathways. Copyright © 2013 Elsevier Inc. All rights

  7. Inhibition of soluble epoxide hydrolase attenuates endothelial dysfunction in animal models of diabetes, obesity and hypertension.

    PubMed

    Zhang, Le-Ning; Vincelette, Jon; Chen, Dawn; Gless, Richard D; Anandan, Sampath-Kumar; Rubanyi, Gabor M; Webb, Heather K; MacIntyre, D Euan; Wang, Yi-Xin Jim

    2011-03-01

    Endothelial dysfunction is a hallmark of, and plays a pivotal role in the pathogenesis of cardiometabolic diseases, including type II diabetes, obesity, and hypertension. It has been well established that epoxyeicosatrienoic acids (EETs) act as an endothelial derived hyperpolarization factor (EDHF). Soluble epoxide hydrolase (s-EH) rapidly hydrolyses certain epoxylipids (e.g. EETs) to less bioactive diols (DHETs), thereby attenuating the evoked vasodilator effects. The aim of the present study was to examine if inhibition of s-EH can restore impaired endothelial function in three animal models of cardiometabolic diseases. Isolated vessel rings of the aorta and/or mesenteric artery from mice or rats were pre-contracted using phenylephrine or U46619. Endothelium-dependent and independent vasorelaxation to acetylcholine and sodium nitroprusside (SNP) were measured using wire myography in vessels isolated from db/db or diet-induced obesity (DIO) mice, and angiotensin II-induced hypertensive rats treated chronically with s-EH inhibitors AR9281 or AR9276 or with vehicle. Vasorelaxation to acetylcholine, but not to SNP was severely impaired in all three animal models. Oral administration of AR9281 or AR9276 abolished whole blood s-EH activity, elevated epoxy/diol lipid ratio, and abrogated endothelial dysfunction in all three models. Incubating the mesenteric artery of db/db mice with L-NAME and indomethacin to block nitric oxide (NO) and prostacyclin formation did not affect AR9821-induced improvement of endothelial function. These data indicate that inhibition of s-EH ameliorates endothelial dysfunction and that effects in the db/db model are independent of the presence of NO and cyclooxygenase derived prostanoids. Thus, preserving vasodilator EETs by inhibition of s-EH may be of therapeutic benefit by improving endothelial function in cardiometabolic diseases. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Inhibition of matrix metalloproteinase-2 improves endothelial function and prevents hypertension in insulin-resistant rats

    PubMed Central

    Nagareddy, PR; Rajput, PS; Vasudevan, H; McClure, B; Kumar, U; MacLeod, KM; McNeill, JH

    2012-01-01

    BACKGROUND AND PURPOSE Insulin resistance is often found to be associated with high blood pressure. We propose that in insulin-resistant hypertension, endothelial dysfunction is the consequence of increased activity of vascular MMP-2. As MMP-2 proteolytically cleaves a number of extracellular matrix proteins, we hypothesized that MMP-2 impairs endothelial function by proteolytic degradation of endothelial NOS (eNOS) or its cofactor, heat shock protein 90 (HSP90). EXPERIMENTAL APPROACH We tested our hypothesis in bovine coronary artery endothelial cells and fructose-fed hypertensive rats (FHR), a model of acquired systolic hypertension and insulin resistance. KEY RESULTS Treatment of FHRs with the MMP inhibitor doxycycline, preserved endothelial function as well as prevented the development of hypertension, suggesting that MMPs impair endothelial function. Furthermore, incubating endothelial cells in vitro with a recombinant MMP-2 decreased NO production in a dose-dependent manner. Using substrate cleavage assays and immunofluorescence microscopy studies, we found that MMP-2 not only cleaves and degrades HSP90, an eNOS cofactor but also co-localizes with both eNOS and HSP90 in endothelial cells, suggesting that MMPs functionally interact with the eNOS system. Treatment of FHRs with doxycycline attenuated the decrease in eNOS and HSP90 expression but did not improve insulin sensitivity. CONCLUSIONS AND IMPLICATIONS Our data suggest that increased activity of MMP-2 in FHRs impairs endothelial function and promotes hypertension. Inhibition of MMP-2 could be a potential therapeutic strategy for the management of hypertension. PMID:21740410

  9. Inhibition of dipeptidyl peptidase 4 regulates microvascular endothelial growth induced by inflammatory cytokines

    SciTech Connect

    Takasawa, Wataru; Ohnuma, Kei; Hatano, Ryo; Endo, Yuko; Dang, Nam H.

    2010-10-08

    Research highlights: {yields} TNF-{alpha} or IL-1{beta} induces EC proliferation with reduction of CD26 expression. {yields} CD26 siRNA or DPP-4 inhibition enhances TNF-{alpha} or IL-1{beta}-induced EC proliferation. {yields} Loss of CD26/DPP-4 enhances aortic sprouting induced by TNF-{alpha} or IL-1{beta}. {yields} Capillary formation induced by TNF-{alpha} or IL-1{beta} is enahced in the CD26{sup -/-} mice. -- Abstract: CD26/DPP-4 is abundantly expressed on capillary of inflamed lesion as well as effector T cells. Recently, CD26/dipeptidyl peptidase 4 (DPP-4) inhibition has been used as a novel oral therapeutic approach for patients with type 2 diabetes. While accumulating data indicate that vascular inflammation is a key feature of both micro- and macro-vascular complications in diabetes, the direct role of CD26/DPP-4 in endothelial biology is to be elucidated. We herein showed that proinflammatory cytokines such as tumor necrosis factor or interleukin-1 reduce expression of CD26 on microvascular endothelial cells, and that genetical or pharmacological inhibition of CD26/DPP-4 enhances endothelial growth both in vitro and in vivo. With DPP-4 inhibitors being used widely in the treatment of type 2 diabetes, our data strongly suggest that DPP-4 inhibition plays a pivotal role in endothelial growth and may have a potential role in the recovery of local circulation following diabetic vascular complications.

  10. Adiporedoxin suppresses endothelial activation via inhibiting MAPK and NF-κB signaling

    PubMed Central

    He, Hui; Guo, Fang; Li, Yong; Saaoud, Fatma; Kimmis, Brooks D.; Sandhu, Jeena; Fan, Michelle; Maulik, Dev; Lessner, Susan; Papasian, Christopher J.; Fan, Daping; Jiang, Zhisheng; Fu, Mingui

    2016-01-01

    Adiporedoxin (Adrx) is a recently discovered redox regulatory protein that is preferentially expressed in adipose tissue and plays a critical role in the regulation of metabolism via its modulation of adipocyte protein secretion. We here report that Adrx suppresses endothelial cell activation via inhibiting MAPK and NF-kB signaling pathways. Adrx is constitutively expressed in human vascular endothelial cells, and significantly induced by a variety of stimuli such as TNFα, IL-1β, H2O2 and OxLDL. Overexpression of Adrx significantly attenuated TNFα-induced expression of VCAM-1 and ICAM-1, and thus reduced monocyte adherence to human umbilical vein endothelial cells (HUVECs). Conversely, siRNA-mediated knockdown of Adrx increased TNFα-induced expression of adhesion molecules and monocyte adherence to HUVECs. Furthermore, forced expression of Adrx decreased TNFα-induced activation of ERK1/2, JNK, p38 and IKKs in HUVECs. Adrx mutant in the CXXC motif that lost its anti-redox activity is less efficient than the wild-type Adrx, suggesting that Adrx-mediated inhibition of endothelial activation is partially dependent on its antioxidant activity. Finally, Adrx expression was markedly increased in human atheroma compared with normal tissue from the same carotid arteries. These results suggest that Adrx is an endogenous inhibitor of endothelial activation, and might be a therapeutic target for vascular inflammatory diseases. PMID:27941911

  11. Synergistic Inhibition of Endothelial Cell Proliferation, Tube Formation, and Sprouting by Cyclosporin A and Itraconazole

    PubMed Central

    Nacev, Benjamin A.; Liu, Jun O.

    2011-01-01

    Pathological angiogenesis contributes to a number of diseases including cancer and macular degeneration. Although angiogenesis inhibitors are available in the clinic, their efficacy against most cancers is modest due in part to the existence of alternative and compensatory signaling pathways. Given that angiogenesis is dependent on multiple growth factors and a broad signaling network in vivo, we sought to explore the potential of multidrug cocktails for angiogenesis inhibition. We have screened 741 clinical drug combinations for the synergistic inhibition of endothelial cell proliferation. We focused specifically on existing clinical drugs since the re-purposing of clinical drugs allows for a more rapid and cost effective transition to clinical studies when compared to new drug entities. Our screen identified cyclosporin A (CsA), an immunosuppressant, and itraconazole, an antifungal drug, as a synergistic pair of inhibitors of endothelial cell proliferation. In combination, the IC50 dose of each drug is reduced by 3 to 9 fold. We also tested the ability of the combination to inhibit endothelial cell tube formation and sprouting, which are dependent on two essential processes in angiogenesis, endothelial cell migration and differentiation. We found that CsA and itraconazole synergistically inhibit tube network size and sprout formation. Lastly, we tested the combination on human foreskin fibroblast viability as well as Jurkat T cell and HeLa cell proliferation, and found that endothelial cells are selectively targeted. Thus, it is possible to combine existing clinical drugs to synergistically inhibit in vitro models of angiogenesis. This strategy may be useful in pursuing the next generation of antiangiogenesis therapy. PMID:21969860

  12. Inhibition of Aberrant MicroRNA-133a Expression in Endothelial Cells by Statin Prevents Endothelial Dysfunction by Targeting GTP Cyclohydrolase 1 in Vivo

    PubMed Central

    Li, Peng; Yin, Ya-Ling; Guo, Tao; Sun, Xue-Ying; Ma, Hui; Zhu, Mo-Li; Zhao, Fan-Rong; Xu, Ping; Chen, Yuan; Wan, Guang-Rui; Jiang, Fan; Peng, Qi-Sheng; Liu, Chao; Liu, Li-Ying

    2016-01-01

    Background: GTP cyclohydrolase 1 (GCH1) deficiency is critical for endothelial nitric oxide synthase uncoupling in endothelial dysfunction. MicroRNAs (miRs) are a class of regulatory RNAs that negatively regulate gene expression. We investigated whether statins prevent endothelial dysfunction via miR-dependent GCH1 upregulation. Methods: Endothelial function was assessed by measuring acetylcholine-induced vasorelaxation in the organ chamber. MiR-133a expression was assessed by quantitative reverse transcription polymerase chain reaction and fluorescence in situ hybridization. Results: We first demonstrated that GCH1 mRNA is a target of miR-133a. In endothelial cells, miR-133a was robustly induced by cytokines/oxidants and inhibited by lovastatin. Furthermore, lovastatin upregulated GCH1 and tetrahydrobiopterin, and recoupled endothelial nitric oxide synthase in stressed endothelial cells. These actions of lovastatin were abolished by enforced miR-133a expression and were mirrored by a miR-133a antagomir. In mice, hyperlipidemia- or hyperglycemia-induced ectopic miR-133a expression in the vascular endothelium, reduced GCH1 protein and tetrahydrobiopterin levels, and impaired endothelial function, which were reversed by lovastatin or miR-133a antagomir. These beneficial effects of lovastatin in mice were abrogated by in vivo miR-133a overexpression or GCH1 knockdown. In rats, multiple cardiovascular risk factors including hyperglycemia, dyslipidemia, and hyperhomocysteinemia resulted in increased miR-133a vascular expression, reduced GCH1 expression, uncoupled endothelial nitric oxide synthase function, and induced endothelial dysfunction, which were prevented by lovastatin. Conclusions: Statin inhibits aberrant miR-133a expression in the vascular endothelium to prevent endothelial dysfunction by targeting GCH1. Therefore, miR-133a represents an important therapeutic target for preventing cardiovascular diseases. PMID:27765794

  13. Curcumin protects endothelial cells against homocysteine induced injury through inhibiting inflammation

    PubMed Central

    Li, Jian; Luo, Ming; Xie, Nanzi; Wang, Jianxin; Chen, Li

    2016-01-01

    Objective: This study aimed to investigate the protective effects of curcumin on the homocysteine (HCY) induced injury to the endothelial cells. Methods: Endothelial cells were treated with HCY at different concentrations, and MTT assay was employed to determine an optimal concentration of HCY. Cells were divided into 3 groups: normal control group, HCY group and HCY + curcumin group. In curcumin group, cells were pretreated with 2.5 mmol/L HCY for 2 h and then incubated with curcumin at different concentrations. MTT assay was employed to detect the cell viability. ELISA was performed to detect the content of IL-8 in the supernatant. Western blotting was used to detect NF-κB expression in cells. Results: (1) Endothelial cells were polygonal or stone-like, or aggregated to form masses, and then gradually became long spindle shaped, cell body enlarged, cells were rich in cytoplasm, and immunohistochemistry for factor VIII showed positive. (2) MTT assay showed HCY at ≥2.5 mmol/L caused significant damage to endothelial cells as compared to control group. Thus, 2.5 mmol/L HCY was used in following experiments. (3) ELISA showed IL-8 in the supernatant increased significantly in a time dependent manner after HCY treatment (P<0.01), but curcumin could significantly inhibit the IL-8 secretion in endothelial cells after HCY treatment. (4) Western blotting showed HCY was able to markedly increase NF-κB expression, which, however, was significantly inhibited by curcumin. Conclusion: Curcumin is able to protect the endothelial cells against HCY induced injury through inhibiting NF-κB activation and down-regulating IL-8 expression. PMID:27904665

  14. High molecular weight kininogen inhibition of endothelial cell function on biomaterials.

    PubMed

    Voskerician, G; Anderson, J M; Ziats, N P

    2000-07-01

    Synthetic vascular grafts implanted into humans fail to develop a complete endothelial lining. In previous studies, we have shown that high-molecular-weight kininogens (HMWK) adsorb to the surfaces of biomaterials. In addition, it has been demonstrated that these proteins modulate cellular function. In the present study, we report on the adhesion and proliferation of human umbilical-vein endothelial cells (HUVEC) on tissue culture polystyrene, glass, polyurethane, and Mylar(trade mark) surfaces coated with human HMWK, either single-chain HMWK (SC-HMWK) or double-chain HMWK (DC-HMWK). Surfaces coated with fibronectin served as a positive control for these experiments. Parallel experiments were performed in which HUVEC were allowed to migrate from crosslinked dextran microcarrier beads (Cytodex 2) onto HMWK-coated surfaces. Our results indicate that HMWK-coated surfaces inhibit endothelial cell adhesion, proliferation, and migration at 24 and 72 h, and this inhibition is concentration dependent. To determine a potential mechanism for this inhibitory phenomenon, cells were stained for cytoskeletal actin filaments using rhodamine-phalloidin. Endothelial cells on HMWK-coated surfaces displayed F-actin filament reorganization/disassembly, characterized by the absence of peripheral actin bands in focal adhesion contacts. We conclude that HMWK inhibit endothelial cell adhesion, proliferation, and migration on a variety of biomaterial surfaces. This inhibitory effect may play a role in promoting the lack of endothelialization in synthetic vascular grafts, which is thought to play a significant role in the failure of these devices. Copyright 2000 John Wiley & Sons, Inc.

  15. The Antifungal Drug Itraconazole Inhibits Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) Glycosylation, Trafficking, and Signaling in Endothelial Cells*

    PubMed Central

    Nacev, Benjamin A.; Grassi, Paola; Dell, Anne; Haslam, Stuart M.; Liu, Jun O.

    2011-01-01

    Itraconazole is a safe and widely used antifungal drug that was recently found to possess potent antiangiogenic activity. Currently, there are four active clinical trials evaluating itraconazole as a cancer therapeutic. Tumor growth is dependent on angiogenesis, which is driven by the secretion of growth factors from the tumor itself. We report here that itraconazole significantly inhibited the binding of vascular endothelial growth factor (VEGF) to VEGF receptor 2 (VEGFR2) and that both VEGFR2 and an immediate downstream substrate, phospholipase C γ1, failed to become activated after VEGF stimulation. These effects were due to a defect in VEGFR2 trafficking, leading to a decrease in cell surface expression, and were associated with the accumulation of immature N-glycans on VEGFR2. Small molecule inducers of lysosomal cholesterol accumulation and mammalian target of rapamycin (mTOR) inhibition, two previously reported itraconazole activities, failed to recapitulate itraconazole's effects on VEGFR2 glycosylation and signaling. Likewise, glycosylation inhibitors did not alter cholesterol trafficking or inhibit mTOR. Repletion of cellular cholesterol levels, which was known to rescue the effects of itraconazole on mTOR and cholesterol trafficking, was also able to restore VEGFR2 glycosylation and signaling. This suggests that the new effects of itraconazole occur in parallel to those previously reported but are downstream of a common target. We also demonstrated that itraconazole globally reduced poly-N-acetyllactosamine and tetra-antennary complex N-glycans in endothelial cells and induced hypoglycosylation of the epidermal growth factor receptor in a renal cell carcinoma line, suggesting that itraconazole's effects extend beyond VEGFR2. PMID:22025615

  16. Phloroglucinol Inhibits the in vitro Differentiation Potential of CD34 Positive Cells into Endothelial Progenitor Cells

    PubMed Central

    Kwon, Yi-Hong; Lee, Jun-Hee; Jung, Seok-Yun; Kim, Jae-Won; Lee, Sang-Hun; Lee, Dong-Hyung; Lee, Kyu-Sup; Lee, Boo-Yong; Kwon, Sang-Mo

    2012-01-01

    Inhibiting the bioactivities of circulating endothelial progenitor cells (EPCs) results in significant inhibition of neovessel formation during tumor angiogenesis. To investigate the potential effect of phloroglucinol as an EPC inhibitor, we performed several in vitro functional assays using CD34+ cells isolated from human umbilical cord blood (HUCB). Although a high treatment dose of phloroglucinol did not show any cell toxicity, it specifically induced the cell death of EPCs under serum free conditions through apoptosis. In the EPC colony-forming assay (EPC-CFA), we observed a significant decreased in the small EPC-CFUs for the phloroglucinol group, implying that phloroglucinol inhibited the early stage of EPC commitment. In addition, in the in vitro expansion assay using CD34+ cells, treatment with phloroglucinol was shown to inhibit endothelial lineage commitment, as demonstrated by the decrease in endothelial surface markers of EPCs including CD34+, CD34+/CD133+, CD34+/CD31+ and CD34+/CXCR4+. This is the first report to demonstrate that phloroglucinol can inhibit the functional bioactivities of EPCs, indicating that phloroglucinol may be used as an EPC inhibitor in the development of biosafe anti-tumor drugs that target tumor angiogenesis. PMID:24116289

  17. Delphinidin Inhibits Tumor Growth by Acting on VEGF Signalling in Endothelial Cells

    PubMed Central

    Anton, Anita; Justiniano, Hélène; Soleti, Raffaella; Alabed Alibrahim, Eid; Simard, Gilles; Andriantsitohaina, Ramaroson; Lugnier, Claire

    2015-01-01

    The vasculoprotective properties of delphinidin are driven mainly by its action on endothelial cells. Moreover, delphinidin displays anti-angiogenic properties in both in vitro and in vivo angiogenesis models and thereby might prevent the development of tumors associated with excessive vascularization. This study was aimed to test the effect of delphinidin on melanoma-induced tumor growth with emphasis on its molecular mechanism on endothelial cells. Delphinidin treatment significantly decreased in vivo tumor growth induced by B16-F10 melanoma cell xenograft in mice. In vitro, delphinidin was not able to inhibit VEGFR2-mediated B16-F10 melanoma cell proliferation but it specifically reduced basal and VEGFR2-mediated endothelial cell proliferation. The anti-proliferative effect of delphinidin was reversed either by the MEK1/2 MAP kinase inhibitor, U-0126, or the PI3K inhibitor, LY-294002. VEGF-induced proliferation was reduced either by U-0126 or LY-294002. Under these conditions, delphinidin failed to decrease further endothelial cell proliferation. Delphinidin prevented VEGF-induced phosphorylation of ERK1/2 and p38 MAPK and decreased the expression of the transcription factors, CREB and ATF1. Finally, delphinidin was more potent in inhibiting in vitro cyclic nucleotide phosphodiesterases (PDEs), PDE1 and PDE2, compared to PDE3-PDE5. Altogether delphinidin reduced tumor growth of melanoma cell in vivo by acting specifically on endothelial cell proliferation. The mechanism implies an association between inhibition of VEGF-induced proliferation via VEGFR2 signalling, MAPK, PI3K and at transcription level on CREB/ATF1 factors, and the inhibition of PDE2. In conjunction with our previous studies, we demonstrate that delphinidin is a promising compound to prevent pathologies associated with generation of vascular network in tumorigenesis. PMID:26694325

  18. TGF-{beta}2 inhibits AKT activation and FGF-2-induced corneal endothelial cell proliferation

    SciTech Connect

    Lu Jiawei; Lu Zhenyu; Reinach, Peter

    2006-11-01

    The corneal endothelial cells form a boundary layer between anterior chamber and cornea. This single cell layer is important to maintain cornea transparency by eliciting net fluid transport into the anterior chamber. Injuries of the corneal endothelial layer in humans lead to corneal swelling and translucence. This hindrance is thought to be due to limited proliferative capacity of the endothelial layer. Fibroblast growth factor 2 (FGF-2) and transforming growth factor-beta 2 (TGF-{beta}2) are both found in aqueous humor, and these two cytokines promote and inhibit cell growth, respectively. The intracellular signaling mechanisms by which TGF-{beta}2 suppresses the mitogenic response to FGF-2, however, remain unclear. We have addressed this question by investigating potential crosstalk between FGF-2-induced and TGF-{beta}2-regulated intracellular signaling events in cultured bovine corneal endothelial (BCE) cells. We found that TGF-{beta}2 and FGF-2 oppositely affect BCE cell proliferation and TGF-{beta}2 can override the stimulating effects of FGF-2 by increasing COX-2 expression in these cells. Consistent with these findings, overexpression of COX-2 significantly reduced FGF-2-induced cell proliferation whereas a COX-2 specific inhibitor NS398 reversed the effect of TGF-{beta}2 on FGF-2-induced cell proliferation. The COX-2 product prostaglandin E2 (PGE-2) blocks FGF-2-induced cell proliferation. Whereas FGF-2 stimulates cell proliferation by activating the AKT pathway, TGF-{beta}2 and PGE-2 both inhibit this pathway. In accordance with the effect of PGE-2, cAMP also inhibits FGF-2-induced AKT activation. These findings suggest that the mitogenic response to FGF-2 in vivo in the corneal endothelial layer may be inhibited by TGF-{beta}2-induced suppression of the PI3-kinase/AKT signaling pathway.

  19. [Knockdown of RUNX3 inhibits hypoxia-induced endothelial-to-mesenchymal transition of human cardiac microvascular endothelial cells].

    PubMed

    Liu, Yanhua; Li, Bingong; Wang, Yuqin; Wang, Delong; Zou, Jin; Ke, Xuan; Hao, Yanqin

    2016-12-01

    Objective To investigate the effects of Runt-related transcription factor 3 (RUNX3) knockdown on hypoxia-induced endothelial-to-mesenchymal transition (EndoMT) of human cardiac microvascular endothelial cells (HCMECs), and elucidate the underlying molecular mechanism. Methods HCMECs were cultured in hypoxic conditions and infected with RUNX3-RNAi lentivirus to knock-down the expression of RUNX3. Reverse transcription PCR was performed to detect the mRNA expressions of RUNX3 and EndoMT related genes such as CD31, vascular endothelial cadherin (VE-cadherin), α-smooth muscle actin (α-SMA) and fibroblast-specific protein-1 (FSP-1); Western blotting was used to determine the protein expressions of RUNX3, CD31, α-SMA and another molecules involved in EndoMT; and immunofluorescence cytochemistry was applied to observe the colocalization of CD31 and α-SMA. Results Hypoxia induced the transition of HCMECs to mesenchymal cells. Hypoxia up-regulated the expression of TGF-β2, Smad2/3, phosphorylation of Smad2/3 (p-Smad2/3), Notch-1, Hes1, and Hey1; knockdown of RUNX3 down-regulated the levels of Smad2/3, p-Smad2/3, Hes1, and Hey1 to different extents, and raised the levels of TGF-β2 and Notch-1. Conclusion Knockdown of RUNX3 in HCMECs attenuates hypoxia-induced EndoMT via partially inhibiting TGF-β and Notch signaling pathway.

  20. TRAF6 inhibits proangiogenic signals in endothelial cells and regulates the expression of vascular endothelial growth factor

    SciTech Connect

    Bruneau, Sarah; Datta, Dipak; Flaxenburg, Jesse A.; Pal, Soumitro; Briscoe, David M.

    2012-03-02

    Highlights: Black-Right-Pointing-Pointer TNF-receptor associated factors (TRAFs) function in the angiogenesis response. Black-Right-Pointing-Pointer TRAF6 regulates basal and inducible expression of VEGF in endothelial cells (EC). Black-Right-Pointing-Pointer TRAF6 is an endogenous inhibitor of EC proliferation and migration in EC. Black-Right-Pointing-Pointer TRAF6 inhibits VEGF expression in part via its ability to regulate Src signaling. -- Abstract: TNF-family molecules induce the expression Vascular Endothelial Growth Factor (VEGF) in endothelial cells (EC) and elicit signaling responses that result in angiogenesis. However, the role of TNF-receptor associated factors (TRAFs) as upstream regulators of VEGF expression or as mediators of angiogenesis is not known. In this study, HUVEC were cotransfected with a full-length VEGF promoter-luciferase construct and siRNAs to TRAF 1, -2, -3, -5, -6, and promoter activity was measured. Paradoxically, rather than inhibiting VEGF expression, we found that knockdown of TRAF6 resulted in a 4-6-fold increase in basal VEGF promoter activity compared to control siRNA-transfected EC (P < 0.0001). In addition, knockdown of TRAF 1, -2, -3 or -5 resulted in a slight increase or no change in VEGF promoter activation. Using [{sup 3}H]thymidine incorporation assays as well as the in vitro wound healing assay, we also found that basal rates of EC proliferation and migration were increased following TRAF6 knockdown; and this response was inhibited by the addition of a blocking anti-VEGF antibody into cell cultures. Using a limited protein array to gain insight into TRAF6-dependent intermediary signaling responses, we observed that TRAF6 knockdown resulted in an increase in the activity of Src family kinases. In addition, we found that treatment with AZD-0530, a pharmacological Src inhibitor, reduced the regulatory effect of TRAF6 knockdown on VEGF promoter activity. Collectively, these findings define a novel pro-angiogenic signaling

  1. Linagliptin but not Sitagliptin inhibited transforming growth factor-β2-induced endothelial DPP-4 activity and the endothelial-mesenchymal transition.

    PubMed

    Shi, Sen; Kanasaki, Keizo; Koya, Daisuke

    2016-02-26

    Dipeptidyl peptidase (DPP)-4 plays an important role in endothelial cell biology. We have shown that the DPP-4 inhibitor Linagliptin can inhibit the endothelial-mesenchymal transition (EndMT) and ameliorate diabetic kidney fibrosis associated with the suppression of DPP-4 protein levels via the induction of miR-29. The current study demonstrated that such effects of Linagliptin on endothelial cell profibrotic programs were drug-specific but not class effects. In the cell-free system, both Linagliptin and Sitagliptin inhibited recombinant DPP-4 activity in a concentration-dependent manner. Linagliptin can inhibit all of the following: DPP-4 activity and protein level, integrin β1 protein levels, EndMT, and DPP-4 3'UTR activity; Sitagliptin, however, inhibited none of these in the current study. Additionally, TGF-β2 induced both the induction of VEGF-R1 and the suppression of VEGF-R2 levels in endothelial cells, and both were inhibited by Linagliptin but not by Sitagliptin. miR-29, the miR that negatively regulates the 3'UTR of DPP-4 mRNA, was suppressed by TGF-β2 and restored by Linagliptin but not by Sitagliptin. Following the overexpression of pCMV-DPP-4-GFP and pCMV6-Myc-DPP-4 in endothelial cells, the proximity of Myc-DPP-4 and DPP-4-GFP was suppressed by Linagliptin but not by Sitagliptin, suggesting that only Linagliptin inhibited the homo-dimer formation of DPP-4 in endothelial cells; this difference in activity between the two gliptins could explain their diverse effects on endothelial cell biology. In conclusion, each of the DPP-4 inhibitors may have unique drug-specific effects.

  2. Ascorbate inhibits platelet-endothelial adhesion in an in-vitro model of sepsis via reduced endothelial surface P-selectin expression.

    PubMed

    Secor, Dan; Swarbreck, Scott; Ellis, Christopher G; Sharpe, Michael D; Feng, Qingping; Tyml, Karel

    2017-01-01

    Plugging of the capillary bed can lead to organ failure and mortality in sepsis. We have reported that intravenous ascorbate injection reduces platelet adhesion to the capillary wall and capillary plugging in septic mice. Both platelet adhesion and capillary plugging require P-selectin, a key adhesion molecule. To elucidate the beneficial effect of ascorbate, we hypothesized that ascorbate reduces platelet-endothelial adhesion by reducing P-selectin surface expression in endothelial cells. We used mouse platelets, and monolayers of cultured microvascular endothelial cells (mouse skeletal muscle origin) stimulated with lipopolysaccharide, to examine platelet-endothelial adhesion. P-selectin mRNA expression in endothelial cells was determined by real-time PCR and P-selectin protein expression at the surface of these cells by immunofluorescence. Secretion of von Willebrand factor from cells into the supernatant (a measure of P-selectin-containing granule exocytosis) was determined by ELISA. Lipopolysaccharide (10 μg/ml, 1 h) increased platelet-endothelial adhesion. P-selectin-blocking antibody inhibited this adhesion. Lipopolysaccharide also increased P-selectin mRNA in endothelial cells, P-selectin expression at the endothelial surface, and von Willebrand factor secretion. Ascorbate pretreatment (100 μmol/l, 4 h) inhibited the increased platelet adhesion, surface expression of P-selectin, and von Willebrand factor secretion, but not the increase in P-selectin mRNA. The lipopolysaccharide-induced increase in platelet-endothelial adhesion requires P-selectin presence at the endothelial surface. Ascorbate's ability to reduce this presence could be important in reducing both platelet adhesion to the capillary wall and capillary plugging in sepsis.

  3. Tumor endothelial marker 5 expression in endothelial cells during capillary morphogenesis is induced by the small GTPase Rac and mediates contact inhibition of cell proliferation

    SciTech Connect

    Vallon, Mario; Rohde, Franziska; Janssen, Klaus-Peter; Essler, Markus

    2010-02-01

    Tumor endothelial marker (TEM) 5 is an adhesion G-protein-coupled receptor upregulated in endothelial cells during tumor and physiologic angiogenesis. So far, the mechanisms leading to upregulation of TEM5 and its function during angiogenesis have not been identified. Here, we report that TEM5 expression in endothelial cells is induced during capillary-like network formation on Matrigel, during capillary morphogenesis in a three-dimensional collagen I matrix, and upon confluence on a two-dimensional matrix. TEM5 expression was not induced by a variety of soluble angiogenic factors, including VEGF and bFGF, in subconfluent endothelial cells. TEM5 upregulation was blocked by toxin B from Clostridium difficile, an inhibitor of the small GTPases Rho, Rac, and Cdc42. The Rho inhibitor C3 transferase from Clostridium botulinum did not affect TEM5 expression, whereas the Rac inhibitor NSC23766 suppressed TEM5 upregulation. An excess of the soluble TEM5 extracellular domain or an inhibitory monoclonal TEM5 antibody blocked contact inhibition of endothelial cell proliferation resulting in multilayered islands within the endothelial monolayer and increased vessel density during capillary formation. Based on our results we conclude that TEM5 expression during capillary morphogenesis is induced by the small GTPase Rac and mediates contact inhibition of proliferation in endothelial cells.

  4. Carbon Ion Radiation Inhibits Glioma and Endothelial Cell Migration Induced by Secreted VEGF

    PubMed Central

    Liu, Yang; Liu, Yuanyuan; Sun, Chao; Gan, Lu; Zhang, Luwei; Mao, Aihong; Du, Yuting; Zhou, Rong; Zhang, Hong

    2014-01-01

    This study evaluated the effects of carbon ion and X-ray radiation and the tumor microenvironment on the migration of glioma and endothelial cells, a key process in tumorigenesis and angiogenesis during cancer progression. C6 glioma and human microvascular endothelial cells were treated with conditioned medium from cultures of glioma cells irradiated at a range of doses and the migration of both cell types, tube formation by endothelial cells, as well as the expression and secretion of migration-related proteins were evaluated. Exposure to X-ray radiation-conditioned medium induced dose-dependent increases in cell migration and tube formation, which were accompanied by an upregulation of vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)-2 and -9 expression. However, glioma cells treated with conditioned medium of cells irradiated at a carbon ion dose of 4.0 Gy showed a marked decrease in migratory potential and VEGF secretion relative to non-irradiated cells. The application of recombinant VEGF165 stimulated migration in glioma and endothelial cells, which was associated with increased FAK phosphorylation at Tyr861, suggesting that the suppression of cell migration by carbon ion radiation could be via VEGF-activated FAK signaling. Taken together, these findings indicate that carbon ion may be superior to X-ray radiation for inhibiting tumorigenesis and angiogenesis through modulation of VEGF level in the glioma microenvironment. PMID:24893038

  5. Decursin inhibits vasculogenesis in early tumor progression by suppression of endothelial progenitor cell differentiation and function.

    PubMed

    Jung, Seok Yun; Choi, Jin Hwa; Kwon, Sang-Mo; Masuda, Haruchika; Asahara, Takayuki; Lee, You-Mie

    2012-05-01

    Endothelial progenitor cells (EPCs) contribute to the tumor vasculature during tumor progression. Decursin isolated from the herb Angelica gigas is known to possess potent anti-inflammatory activities. Recently, we reported that decursin is a novel candidate for an angiogenesis inhibitor [Jung et al., 2009]. In this study, we investigated whether decursin regulates EPC differentiation and function to inhibit tumor vasculogenesis. We isolated AC133+ cells from human cord blood and decursin significantly decreased the number of EPC colony forming units of human cord blood-derived AC133+ cells that produce functional EPC progenies. Decursin dose-dependently decreased the cell number of EPC committing cells as demonstrated by EPC expansion studies. Decursin inhibited EPC differentiation from progenitor cells into spindle-shaped EPC colonies. Additionally, decursin inhibited proliferation and migration of early EPCs isolated from mouse bone marrow. Furthermore, decursin suppressed expression of angiopoietin-2, angiopoietin receptor Tie-2, Flk-1 (vascular endothelial growth factor receptor-2), and endothelial nitric oxide synthase in mouse BM derived EPCs in a dose-dependent manner. Decursin suppressed tube formation ability of EPCs in collaboration with HUVEC. Decursin (4 mg/kg) inhibited tumor-induced mobilization of circulating EPCs (CD34 + /VEGFR-2+ cells) from bone marrow and early incorporation of Dil-Ac-LDL-labeled or green fluorescent protein (GFP)+ EPCs into neovessels of xenograft Lewis lung carcinoma tumors in wild-type- or bone-marrow-transplanted mice. Accordingly, decursin attenuated EPC-derived endothelial cells in neovessels of Lewis lung carcinoma tumor masses grown in mice. Together, decursin likely affects EPC differentiation and function, thereby inhibiting tumor vasculogenesis in early tumorigenesis. Copyright © 2012 Wiley Periodicals, Inc.

  6. TSG attenuates LPC-induced endothelial cells inflammatory damage through notch signaling inhibition.

    PubMed

    Zhao, Jing; Liang, Yuan; Song, Fan; Xu, Shouzhu; Nian, Lun; Zhou, Xuanxuan; Wang, Siwang

    2016-01-01

    Lysophosphatidylcholine (LPC) induces inflammation in endothelial cells (ECs) but the mechanism is not fully understood. The Notch signaling pathway is involved in chronic EC inflammation, but its functions in LPC-induced endothelial inflammatory damage and 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucoside's (TSG) protective effect during LPC-induced inflammatory damage in human umbilical vein endothelial cells (HUVECs) is largely unknown. We report that Notch signaling activation contributed to LPC-induced injury in HUVECs, and that TSG protected HUVECs from LPC-induced injury by antagonizing Notch signaling activation by LPC. γ-secretase inhibitor (DAPT), a specific inhibitor of the Notch signaling pathway, and Notch1 siRNA were used to inhibit Notch activity. HUVECs were exposed to LPC in the presence or absence of TSG, DAPT, and Notch1 siRNA. LPC treatment of HUVECs resulted in reduced cell viability, and Notch1 and Hes1 upregulation. Either silencing of Notch1 by siRNA or pharmacological inhibition of Notch signaling by DAPT prevented the loss of cell viability, and induction of apoptosis, and enhanced expression Notch1, Hes1 and MCP-1 by LPC in HUVECs. Similarly, TSG reduced LPC stimulation of Notch1, Hes1, and MCP-1 expression, prevented the release of IL-6 and CRP and rescued HUVECs from LPC-induced cell damage. Our data indicate that the Notch signaling pathway is a crucial mediator of endothelial inflammatory damage and that TSG protects against endothelial inflammatory damage by inhibiting the Notch signaling pathway. Our findings suggest that targeting Notch signaling by natural products such as TSG is a promising strategy for the prevention and treatment of chronic inflammation associated diseases, including atherosclerosis. © 2015 IUBMB Life, 68(1):37-50, 2016.

  7. Copper induces--and copper chelation by tetrathiomolybdate inhibits--endothelial activation in vitro.

    PubMed

    Wei, Hao; Zhang, Wei-Jian; Leboeuf, Renee; Frei, Balz

    2014-01-01

    Endothelial activation with increased expression of cellular adhesion molecules and chemokines critically contributes to vascular inflammation and atherogenesis. Redox-active transition metal ions play an important role in vascular oxidative stress and inflammation. Therefore, the goal of the present study was to investigate the role of copper in endothelial activation and the potential anti-inflammatory effects of copper chelation by tetrathiomolybdate (TTM) in human aortic endothelial cells (HAECs). Incubating HAECs with cupric sulfate dose- and time-dependently increased mRNA and protein expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and monocyte chemotactic protein-1 (MCP-1). Copper also activated the redox-sensitive transcription factors, nuclear factor kappa B (NF-κB) and activator protein-1 (AP-1), which was inhibited by pretreatment of the cells with TTM. Furthermore, TTM dose-dependently inhibited tumor necrosis factor α (TNFα)-induced activation of NF-κB and AP-1, as well as mRNA and protein expression of VCAM-1, ICAM-1, and MCP-1, which was abolished by preincubating the cells with 5 µM TTM and 15 µM cupric sulfate. The inhibitory effect of TTM on TNFα-induced NF-κB activation was associated with decreased phosphorylation and degradation of IκBα. These data suggest that intracellular copper causes activation of redox-sensitive transcription factors and upregulation of inflammatory mediators in endothelial cells. Copper chelation by TTM may attenuate TNFα-induced endothelial activation and, hence, inhibit vascular inflammation and atherosclerosis.

  8. Arginase inhibition restores NOS coupling and reverses endothelial dysfunction and vascular stiffness in old rats

    PubMed Central

    Kim, Jae Hyung; Bugaj, Lukasz J.; Oh, Young Jun; Bivalacqua, Trinity J.; Ryoo, Sungwoo; Soucy, Kevin G.; Santhanam, Lakshmi; Webb, Alanah; Camara, Andre; Sikka, Gautam; Nyhan, Daniel; Shoukas, Artin A.; Ilies, Monica; Christianson, David W.; Champion, Hunter C.

    2009-01-01

    There is increasing evidence that upregulation of arginase contributes to impaired endothelial function in aging. In this study, we demonstrate that arginase upregulation leads to endothelial nitric oxide synthase (eNOS) uncoupling and that in vivo chronic inhibition of arginase restores nitroso-redox balance, improves endothelial function, and increases vascular compliance in old rats. Arginase activity in old rats was significantly increased compared with that shown in young rats. Old rats had significantly lower nitric oxide (NO) and higher superoxide (O2−) production than young. Acute inhibition of both NOS, with NG-nitro-l-arginine methyl ester, and arginase, with 2(S)-amino- 6-boronohexanoic acid (ABH), significantly reduced O2− production in old rats but not in young. In addition, the ratio of eNOS dimer to monomer in old rats was significantly decreased compared with that shown in young rats. These results suggest that eNOS was uncoupled in old rats. Although the expression of arginase 1 and eNOS was similar in young and old rats, inducible NOS (iNOS) was significantly upregulated. Furthermore, S-nitrosylation of arginase 1 was significantly elevated in old rats. These findings support our previously published finding that iNOS nitrosylates and activates arginase 1 (Santhanam et al., Circ Res 101: 692–702, 2007). Chronic arginase inhibition in old rats preserved eNOS dimer-to-monomer ratio and significantly reduced O2− production and enhanced endothelial-dependent vasorelaxation to ACh. In addition, ABH significantly reduced vascular stiffness in old rats. These data indicate that iNOS-dependent S-nitrosylation of arginase 1 and the increase in arginase activity lead to eNOS uncoupling, contributing to the nitroso-redox imbalance, endothelial dysfunction, and vascular stiffness observed in vascular aging. We suggest that arginase is a viable target for therapy in age-dependent vascular stiffness. PMID:19661445

  9. Propofol inhibits high glucose-induced PP2A expression in human umbilical vein endothelial cells.

    PubMed

    Wu, Qichao; Zhao, Yanjun; Duan, Wenming; Liu, Yi; Chen, Xiangyuan; Zhu, Minmin

    2017-04-01

    Perioperative hyperglycemia is a common clinical metabolic disorder. Hyperglycemia could induce endothelial apoptosis, dysfunction and inflammation, resulting in endothelial injury. Propofol is a widely used anesthetic drug in clinical settings. Our previous studies indicated that propofol, via inhibiting high glucose-induced phosphatase A2 (PP2A) expression, attenuated high glucose-induced reactive oxygen species (ROS) accumulation, thus improving endothelial apoptosis, dysfunction and inflammation. However, the mechanisms by which propofol attenuated high glucose-induced PP2A expression is still obscure. In the present study, we examined how propofol attenuates high glucose-induced endothelial PP2A expression. Compared with 5mM glucose treatment, 15mM glucose up-regulated expression and activity of PP2A, increased cAMP response element binding protein (CREB), Ca(2+)-calmodulin dependent kinase II (CaMK II) phosphorylation and Ca(2+) accumulation. More importantly, propofol decreased PP2A expression and activity, attenuated CREB, CaMK II phosphorylation and Ca(2+) accumulation in a concentration-dependent manner. Moreover, we demonstrated that the effect of propofol was similar to that of MK801, an inhibitor of NMDA receptor. In contrast, rapastinel, an activator of NMDA receptor, antagonized the effect of propofol. Also, the effect of KN93, an inhibitor of CaMK II, was similar to that of propofol, except KN93 had no effect on 15mM glucose-mediated Ca(2+) accumulation. Our data indicated that propofol, via inhibiting NMDA receptor, attenuated 15mM glucose-induced Ca(2+) accumulation, CaMK II and CREB phosphorylation, thus inhibiting PP2A expression and improving 15mM glucose-induced endothelial dysfunction and inflammation. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Urea immunoliposome inhibits human vascular endothelial cell proliferation for hemangioma treatment

    PubMed Central

    2013-01-01

    Background Urea injection has been used in hemangioma treatment as sclerotherapy. It shrinks vascular endothelial cells and induces degeneration, necrosis, and fibrosis. However, this treatment still has disadvantages, such as lacking targeting and difficulty in controlling the urea dosage. Thus, we designed a urea immunoliposome to improve the efficiency of treatment. Methods The urea liposome was prepared by reverse phase evaporation. Furthermore, the urea immunoliposome was generated by coupling the urea liposome with a vascular endothelial growth factor receptor (VEGFR) monoclonal antibody using the glutaraldehyde cross-linking method. The influence of the urea immunoliposome on cultured human hemangioma vascular endothelial cells was observed preliminarily. Results Urea immunoliposomes showed typical liposome morphology under a transmission electron microscope, with an encapsulation percentage of 54.4% and a coupling rate of 36.84% for anti-VEGFR. Treatment with the urea immunoliposome significantly inhibited the proliferation of hemangioma vascular endothelial cells (HVECs) in a time- and dose-dependent manner. Conclusions The urea immunoliposome that we developed distinctly and persistently inhibited the proliferation of HVECs and is expected to be used in clinical hemangioma treatment. PMID:24266957

  11. Inhibition of NADPH oxidase activation in endothelial cells by ortho-methoxy-substituted catechols.

    PubMed

    Johnson, David K; Schillinger, Kurt J; Kwait, David M; Hughes, Chambers V; McNamara, Erin J; Ishmael, Fauod; O'Donnell, Robert W; Chang, Ming-Mei; Hogg, Michael G; Dordick, Jonathan S; Santhanam, Lakshmi; Ziegler, Linda M; Holland, James A

    2002-01-01

    NADPH oxidase is a major enzymatic source of oxygen free radicals in stimulated endothelial cells (ECs). The ortho-methoxy-substituted catechol, apocynin (4-hydroxy-3-methoxyacetophenone), isolated from the traditional medicinal plant Picrorhiza kurroa, inhibits the release of superoxide anion (O2*-) by this enzyme. The compound acts by blocking the assembly of a functional NADPH oxidase complex. The underlying chemistry of this inhibitory activity, and its physiological significance to EC proliferation, have been investigated. A critical event is the reaction of ortho-methoxy-substituted catechols with reactive oxygen species (ROS) and peroxidase. Analysis of this reaction reveals that apocynin is converted to a symmetrical dimer through the formation of a 5,5' carbon-carbon bond. Both reduced glutathione and L-cysteine inhibit this dimerization process. Catechols without the ortho-methoxy-substituted group do not undergo this chemical reaction. Superoxide production by an endothelial cell-free system incubated with apocynin was nearly completely inhibited after a lagtime for inhibition of ca. 2 min. Conversely, O2*- production was nearly completely inhibited, without a lagtime, by incubation with the dimeric form of apocynin. The apocynin dimer undergoes a two-electron transfer reaction with standard redox potentials of -0.75 and -1.34 V as determined by cyclic voltammetry. Inhibition of endothelial NADPH oxidase by apocynin caused a dose-dependent inhibition of cell proliferation. These findings identify a metabolite of an ortho-methoxy-substituted catechol, which may be the active compound formed within stimulated ECs that prevents NADPH oxidase complex assembly and activation.

  12. Bevacizumab inhibits proliferation of choroidal endothelial cells by regulation of the cell cycle.

    PubMed

    Rusovici, Raluca; Patel, Chirag J; Chalam, Kakarla V

    2013-01-01

    The purpose of this study was to evaluate cell cycle changes in choroidal endothelial cells treated with varying doses of bevacizumab in the presence of a range of concentrations of vascular endothelial growth factor (VEGF). Bevacizumab, a drug widely used in the treatment of neovascular age-related macular degeneration, choroidal neovascularization, and proliferative diabetic retinopathy, neutralizes all isoforms of VEGF. However, the effect of intravitreal administration of bevacizumab on the choroidal endothelial cell cycle has not been established. Monkey choroidal endothelial (RF/6A) cells were treated with VEGF 50 ng/mL and escalating doses of bevacizumab 0.1-2 mg/mL for 72 hours. Cell cycle changes in response to bevacizumab were analyzed by flow cytometry and propidium iodide staining. Cell proliferation was measured using the WST-1 assay. Morphological changes were recorded by bright field cell microscopy. Bevacizumab inhibited proliferation of choroidal endothelial cells by stabilization of the cell cycle in G0/G1 phase. Cell cycle analysis of VEGF-enriched choroidal endothelial cells revealed a predominant increase in the G2/M population (21.84%, P, 0.01) and a decrease in the G0/G1 phase population (55.08%, P, 0.01). Addition of escalating doses of bevacizumab stabilized VEGF-enriched cells in the G0/G1 phase (55.08%, 54.49%, 56.3%, and 64% [P, 0.01]) and arrested proliferation by inhibiting the G2/M phase (21.84%, 21.46%, 20.59%, 20.94%, and 16.1% [P, 0.01]). The increase in G0/G1 subpopulation in VEGF-enriched and bevacizumab-treated cells compared with VEGF-enriched cells alone was dose-dependent. Bevacizumab arrests proliferation of VEGF-enriched choroidal endothelial cells by stabilizing the cell cycle in the G0/G1 phase and inhibiting the G2/M phase in a dose-dependent fashion.

  13. Flavonoids from Citrus unshiu Marc. inhibit cancer cell adhesion to endothelial cells by selective inhibition of VCAM-1.

    PubMed

    Jin, Hana; Lee, Won Sup; Yun, Jeong Won; Jung, Ji Hyun; Yi, Sang Mi; Kim, Hye Jung; Choi, Yung Hyun; Kim, Gonsup; Jung, Jin-Myung; Ryu, Chung Ho; Shin, Sung Chul; Hong, Soon Chan

    2013-11-01

    Citrus fruits have been used as edible fruit and a component of traditional medicine for various diseases including cancer since ancient times. Herein, we investigated the anticancer activity of flavonoids of Citrus unshiu Marc. (FCM) focusing on anti-metastatic effects. We prepared FCM and performed experiments using MDA-MB-231 human breast cancer cells. FCM inhibited TNF-induced cancer cell adhesion to human umbilical vein endothelial cells (HUVECs) without showing any toxicity. FCM inhibited the expression of VCAM-1, but not of ICAM-1, on MDA-MB-231 cells as well as HUVECs. FCM inhibited protein kinase C (PKC) phosphorylation, but not Akt phosphorylation. FCM also inhibited cancer cell invasion in a dose-dependent manner, but not MMP-9 expression. In conclusion, this study suggested that FCM inhibits TNF-induced cancer cell adhesion to HUVECs by inhibiting VCAM-1 through inhibition of PKC, providing evidence that FCM have anti-metastatic activity by inhibiting adhesion molecules and invasion on human breast cancer cells.

  14. The chemokine CXCL13 (BCA-1) inhibits FGF-2 effects on endothelial cells.

    PubMed

    Spinetti, G; Camarda, G; Bernardini, G; Romano Di Peppe, S; Capogrossi, M C; Napolitano, M

    2001-11-23

    Several chemokines, belonging to both the CXC and CC classes, act as positive or negative regulators of angiogenesis. We sought to investigate the role of CXCL13, B cell-attracting chemokine 1 (BCA-1), also known as B-lymphocyte chemoattractant (BLC), on endothelial cell functions. We tested the effect of CXCL13 on HUVEC chemotaxis and proliferation in the presence of fibroblast growth factor (FGF)-2 and found that such chemokine inhibits FGF-2-induced functions, while is not active by itself. To test whether other FGF-2-mediated biological activities may be affected, we evaluated the ability of CXCL13 to rescue HUVEC from starvation-induced apoptosis, as FGF-2 is a survival factor for endothelial cells, and found that CXCL13 partially inhibits such rescue. Multiple mechanisms may be responsible for these biological activities as CXCL13 displaces FGF-2 binding to endothelial cells, inhibits FGF-2 homodimerization, and induces the formation of CXCL13-FGF-2 heterodimers. Our data suggest that CXCL13 may modulate angiogenesis by interfering with FGF-2 activity.

  15. Inhibition of angiotensin converting enzyme activity in cultured endothelial cells by hypoxia.

    PubMed Central

    Stalcup, S A; Lipset, J S; Woan, J M; Leuenberger, P; Mellins, R B

    1979-01-01

    Endothelial cells in tissue culture degrade bradykinin and convert angiotensin I to angiotensin II. These are both functions of a single dipeptidyl hydrolase, angiotensin converting enzyme. Monolayer cultures were prepared from human, rabbit, pig, and calf vessels. Angiotensin converting enzyme activity was assessed by adding either bradykinin or angiotensin I to the cells in culture flasks, and measuring residual peptide over time by radioimmunoassay. Peptide degradation was inhibited by the specific converting enzyme inhibitor, SQ 20881. The flasks were equilibrated with varying hypoxic gas mixtures: hypoxia rapidly (less than 2 min) decreased enzyme activity and room air restored it as rapidly. The extent to which activity was reduced was a direct function of PO2 (r = 0.93, P less than 0.001), and there was no enzyme activity below a PO2 of 30 mm Hg. Four preparations were studied with respect to decrease in enzyme activity by hypoxia: (a) intact cells in monolayer, (b) sonicated cells, (c) sonicated cells from which converting enzyme was partially dissolved by a detergent, and (d) purified converting enzyme. Hypoxia had progressively less of an inhibiting effect on the enzyme activity of the preparations as the degree of cell integrity decreased. Hypoxia inhibits angiotensin converting enzyme activity in cultured endothelial cells, but the effect of hypoxia is not on the enzyme per se, but appears to be a unique characteristic of the endothelial cell. Images PMID:221532

  16. Inhibition of angiotensin converting enzyme activity in cultured endothelial cells by hypoxia.

    PubMed

    Stalcup, S A; Lipset, J S; Woan, J M; Leuenberger, P; Mellins, R B

    1979-05-01

    Endothelial cells in tissue culture degrade bradykinin and convert angiotensin I to angiotensin II. These are both functions of a single dipeptidyl hydrolase, angiotensin converting enzyme. Monolayer cultures were prepared from human, rabbit, pig, and calf vessels. Angiotensin converting enzyme activity was assessed by adding either bradykinin or angiotensin I to the cells in culture flasks, and measuring residual peptide over time by radioimmunoassay. Peptide degradation was inhibited by the specific converting enzyme inhibitor, SQ 20881. The flasks were equilibrated with varying hypoxic gas mixtures: hypoxia rapidly (less than 2 min) decreased enzyme activity and room air restored it as rapidly. The extent to which activity was reduced was a direct function of PO2 (r = 0.93, P less than 0.001), and there was no enzyme activity below a PO2 of 30 mm Hg. Four preparations were studied with respect to decrease in enzyme activity by hypoxia: (a) intact cells in monolayer, (b) sonicated cells, (c) sonicated cells from which converting enzyme was partially dissolved by a detergent, and (d) purified converting enzyme. Hypoxia had progressively less of an inhibiting effect on the enzyme activity of the preparations as the degree of cell integrity decreased. Hypoxia inhibits angiotensin converting enzyme activity in cultured endothelial cells, but the effect of hypoxia is not on the enzyme per se, but appears to be a unique characteristic of the endothelial cell.

  17. Mo polyoxometalate nanoparticles inhibit tumor growth and vascular endothelial growth factor induced angiogenesis

    NASA Astrophysics Data System (ADS)

    Zheng, Wenjing; Yang, Licong; Liu, Ying; Qin, Xiuying; Zhou, Yanhui; Zhou, Yunshan; Liu, Jie

    2014-06-01

    Tumor growth depends on angiogenesis, which can furnish the oxygen and nutrients that proliferate tumor cells. Thus, blocking angiogenesis can be an effective strategy to inhibit tumor growth. In this work, three typical nanoparticles based on polyoxometalates (POMs) have been prepared; we investigated their capability as antitumor and anti-angiogenesis agents. We found that Mo POM nanoparticles, especially complex 3, inhibited the growth of human hepatocellular liver carcinoma cells (HepG2) through cellular reactive oxygen species levels’ elevation and mitochondrial membrane potential damage. Complex 3 also suppressed the proliferation, migration, and tube formation of endothelial cells in vitro and chicken chorioallantoic membrane development ex vivo. Furthermore, western blot analysis of cell signaling molecules indicated that Mo POMs blocked the vascular endothelial growth factor receptor 2-mediated ERK1/2 and AKT signaling pathways in endothelial cells. Using transmission electron microscopy, we demonstrated their cellular uptake and localization within the cytoplasm of HepG2 cells. These results indicate that, owing to the extraordinary physical and chemical properties, Mo POM nanoparticles can significantly inhibit tumor growth and angiogenesis, which makes them potential drug candidates in anticancer and anti-angiogenesis therapies.

  18. Mechanism study of endothelial protection and inhibits platelet activation of low molecular weight fucoidan from Laminaria japonica

    NASA Astrophysics Data System (ADS)

    Chen, Anjin; Zhang, Fang; Shi, Jie; Zhao, Xue; Yan, Meixing

    2016-10-01

    Several studies have indicated that fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica could inhibit the activation of platelets directly by reducing the platelet aggregation. To explore the direct effect of LMW fucoidan on the platelet system furthermore and examine the possible mechanism, the endothelial protection and inhibits platelet activation effects of two LMW fucoidan were investigated. In the present study, Endothelial injury model of rats was made by injection of adrenaline (0.4 mg kg-1) and human umbilical vein endothelial cells were cultured. vWF level was be investigated in vivo and in vitro as an important index of endothelial injury. LMW fucoidan could significantly reduce vWF level in vascular endothelial injury rats and also significantly reduce vWF level in vitro. The number of EMPs was be detected as another important index of endothelial injury. The results showed that LMW fucoidan reduced EMPs stimulated by tumor necrosis factor. In this study, it was found that by inhibiting platelet adhesion, LMW fucoidan played a role in anti-thrombosis and the specific mechanism of action is to inhibit the flow of extracellular Ca2+. All in a word, LMW fucoidan could inhibit the activation of platelets indirectly by reducing the concentration of EMPs and vWF, at the same time; LMW fucoidan inhibited the activation of platelets directly by inhibiting the flow of extracellular Ca2+.

  19. Rapamycin antagonizes TNF induction of VCAM-1 on endothelial cells by inhibiting mTORC2

    PubMed Central

    Wang, Chen; Qin, Lingfeng; Manes, Thomas D.; Kirkiles-Smith, Nancy C.; Tellides, George

    2014-01-01

    Recruitment of circulating leukocytes into inflamed tissues depends on adhesion molecules expressed by endothelial cells (ECs). Here we report that rapamycin pretreatment reduced the ability of TNF-treated ECs to capture T cells under conditions of venular flow. This functional change was caused by inhibition of TNF-induced expression of vascular cell adhesion molecule-1 (VCAM-1) and could be mimicked by knockdown of mammalian target of rapamycin (mTOR) or rictor, but not raptor, implicating mTORC2 as the target of rapamycin for this effect. Mechanistically, mTORC2 acts through Akt to repress Raf1-MEK1/2-ERK1/2 signaling, and inhibition of mTORC2 consequently results in hyperactivation of ERK1/2. Increased ERK1/2 activity antagonizes VCAM-1 expression by repressing TNF induction of the transcription factor IRF-1. Preventing activation of ERK1/2 reduced the ability of rapamycin to inhibit TNF-induced VCAM-1 expression. In vivo, rapamycin inhibited mTORC2 activity and potentiated activation of ERK1/2. These changes correlated with reduced endothelial expression of TNF-induced VCAM-1, which was restored via pharmacological inhibition of ERK1/2. Functionally, rapamycin reduced infiltration of leukocytes into renal glomeruli, an effect which was partially reversed by inhibition of ERK1/2. These data demonstrate a novel mechanism by which rapamycin modulates the ability of vascular endothelium to mediate inflammation and identifies endothelial mTORC2 as a potential therapeutic target. PMID:24516119

  20. 1,25-Dihydroxyvitamin D3 inhibits lipopolysaccharide-induced immune activation in human endothelial cells

    PubMed Central

    Equils, O; Naiki, Y; Shapiro, A M; Michelsen, K; Lu, D; Adams, J; Jordan, S

    2006-01-01

    In addition to its well-known role in mineral and skeletal homeostasis, 1,25-dihydroxyvitamin D3[1,25-(OH)2, D3] regulates the differentiation, growth and function of a broad range of immune system cells, including monocytes, dendritic cells, T and B lymphocytes. Vascular endothelial cells play a major role in the innate immune activation during infections, sepsis and transplant rejection; however, currently there are no data on the effect of 1,25-(OH)2 D3 on microbial antigen-induced endothelial cell activation. Here we show that 1,25-(OH)2 D3 pretreatment of human microvessel endothelial cells (HMEC) inhibited the enteric Gram-negative bacterial lipopolysaccharide (LPS) activation of transcription factor NF-κB and interleukin (IL)-6, IL-8 and regulated upon activation normal T cell exposed and secreted (RANTES) release. The effect of 1,25-(OH)2 D3 was not due to increased cell death or inhibition of endothelial cell proliferation. 1,25-(OH)2 D3 pretreatment of HMEC did not block MyD88-independent LPS-induced interferon (IFN)-β promoter activation. 1,25-(OH)2 D3 pretreatment of HMEC did not modulate Toll-like receptor 4 (TLR4) or MD-2 expression. These data suggest that 1,25-(OH)2 D3 may play a role in LPS-induced immune activation of endothelial cells during Gram-negative bacterial infections, and a suggest a potential role for 1,25-(OH)2 D3 and its analogues as an adjuvant in the treatment of Gram-negative sepsis. PMID:16367934

  1. Febuxostat Inhibition of Endothelial-Bound XO: Implications for Targeting Vascular ROS Production

    PubMed Central

    Malik, Umair Z.; Hundley, Nicholas J.; Romero, Guillermo; Radi, Rafael; Freeman, Bruce A.; Tarpey, Margaret M.; Kelley, Eric E.

    2011-01-01

    Xanthine oxidase (XO) is a critical source of reactive oxygen species (ROS) that contribute to vascular inflammation. Binding of XO to vascular endothelial cell glycosaminoglycans (GAGs) results in significant resistance to inhibition by traditional pyrazolopyrimidine-based inhibitors such as allopurinol. Therefore, we compared the extent of XO inhibition (free and GAG-bound) by allopurinol to febuxostat, a newly approved nonpurine XO-specific inhibitor. In solution, febuxostat was 1000 fold more potent than allopurinol inhibition of XO-dependent uric acid formation (IC50 = 1.8 nM vs. 2.9 μM). Association of XO with heparin-Sepharose 6B (HS6B-XO) had minimal effect on inhibition of uric acid formation by febuxostat (IC50 = 4.4 nM) while further limiting the effect of allopurinol (IC50 = 64 μM). Kinetic analysis of febuxostat inhibition revealed Ki values of 0.96 nM (free) and 0.92 nM (HS6B-XO), confirming equivalent inhibition for both free and GAG-immobilized enzyme. When XO was bound to endothelial cell GAGs, complete enzyme inhibition was observed with 25 nM febuxostat, while no more than 80% inhibition was seen with either allopurinol or oxypurinol, even at concentrations above those tolerated clinically. The superior potency for inhibition of endothelium-associated XO is predictive of a significant role for febuxostat in investigating pathological states where XO-derived ROS are contributive and traditional XO inhibitors are only slightly effective. PMID:21554948

  2. ADAMTS1 inhibits lymphangiogenesis by attenuating phosphorylation of the lymphatic endothelial cell-specific VEGF receptor

    SciTech Connect

    Inagaki, Junko; Takahashi, Katsuyuki; Ogawa, Hiroko; Asano, Keiichi; Faruk Hatipoglu, Omer; Zeynel Cilek, Mehmet; Obika, Masanari; Ohtsuki, Takashi; Hofmann, Matthias; Kusachi, Shozo; Ninomiya, Yoshifumi; Hirohata, Satoshi

    2014-05-01

    Angiogenesis and lymphangiogenesis play roles in malignant tumor progression, dissemination, and metastasis. ADAMTS1, a member of the matrix metalloproteinase family, is known to inhibit angiogenesis. Recombinant ADAMTS1 was shown to strongly inhibit angiogenesis. We investigated whether ADAMTS1 inhibited lymphangiogenesis in the present study. We examined cell proliferation and cell migration in normal human dermal lymphatic microvascular endothelial cells (HMVEC-dLy) transduced with or without adenoviral human ADAMTS1 gene therapy. We then examined the VEGFC/VEGFR3 signal transduction pathway in ADAMTS1-transduced HMVEC-dLy. Cell proliferation and tube formation in Matrigel were significantly lower with transduced ADAMTS1 than with control (non-transduced HMVEC-dLy). The phosphorylation of VEGFR3 was also attenuated by ADAMTS1 gene therapy in HMVEC-dLy. Immunoprecipitation assays revealed that ADAMTS1 formed a complex with VEGFC. Our results demonstrated that ADAMTS1 inhibited lymphangiogenesis in vitro. The data highlight the new function of ADAMTS1 in the regulation of lymphangiogenesis and the therapeutic potential of ADAMTS1 in cancer therapy. - Highlights: • ADAMTS1 significantly inhibited tube formation and cell proliferation in HMVEC-dLy. • Reduced lymph endothelial cell migration in ADAMTS1 transduced co-culture systems. • VEGFC-stimulated phosphorylation of VEGFR3 is attenuated by ADAMTS1. • Reduced phosphorylation of Akt and ERK1/2 in ADAMTS1 treated HMVEC-dLy. • ADAMTS1 binds directly to VEGFC.

  3. Inhibition of proliferation of retinal vascular endothelial cells more effectively than choroidal vascular endothelial cell proliferation by bevacizumab

    PubMed Central

    Mynampati, Bharani Krishna; Sambhav, Kumar; Grover, Sandeep; Chalam, Kakarla V.

    2017-01-01

    AIM To evaluate the differential inhibitory effects of bevacizumab on cell proliferation of vascular endothelial growth factor (VEGF)-stimulated choroidal vascular endothelial cells (CVECs) and retinal vascular endothelial cells (RVECs) in vitro. METHODS VEGF (400 ng/mL) enriched CVECs and RVECs were treated with escalating doses of bevacizumab (0.1, 0.5, 1, 1.5 and 2 mg/mL). Cell proliferation changes were analyzed with WST-1 assay and trypan blue exclusion assay at 48, 72h and 1wk. Morphological changes were recorded with bright field microscopy. RESULTS VEGF enriched RVECs showed significantly more decline of cell viability than CVECs after bevacizumab treatment. One week after treatment, RVEC cell proliferation decreased by 29.7%, 37.5%, 52.8%, 35.9% and 45.6% at 0.1, 0.5, 1.0, 1.5 and 2 mg/mL bevacizumab respectively compared to CVEC proliferation decrease of 4.1%, 7.7%, 2.4%, 4.1% and 17.7% (P<0.05) by WST-1 assay. Trypan blue exclusion assay also revealed similar decrease in RVEC proliferation of 20%, 60%, 73.3%, 80% and 93.3% compared to CVEC proliferation decrease of 4%, 12%, 22.9%, 16.7% and 22.2% respectively (P<0.05). The maximum differential effect between the two cell types was observed at bevacizumab doses of 1.0 and 1.5 mg/mL at all time points. RVECs were 22 fold more sensitive (P<0.01) compared to CVECs (52.8% vs 2.4%) at concentration of 1.0 mg/mL, and 8.7 fold more at 1.5 mg/mL (35.9% vs 4.1%) 1wk after treatment (P<0.05 respectively). CONCLUSION VEGF-enriched RVECs are more susceptible to bevacizumab inhibition than CVECs at clinically used dosage of 1.25 mg and this differential sensitivity between two cell types should be taken into consideration in dosage selection. PMID:28149771

  4. Dietary inhibition of xanthine oxidase attenuates radiation-induced endothelial dysfunction in rat aorta.

    PubMed

    Soucy, Kevin G; Lim, Hyun Kyo; Attarzadeh, David O; Santhanam, Lakshmi; Kim, Jae Hyung; Bhunia, Anil K; Sevinc, Baris; Ryoo, Sungwoo; Vazquez, Marcelo E; Nyhan, Daniel; Shoukas, Artin A; Berkowitz, Dan E

    2010-05-01

    Radiation exposure is associated with the development of various cardiovascular diseases. Although irradiation is known to cause elevated oxidant stress and chronic inflammation, both of which are detrimental to vascular function, the molecular mechanisms remain incompletely understood. We previously demonstrated that radiation causes endothelial dysfunction and increased vascular stiffness by xanthine oxidase (XO) activation. In this study, we investigated whether dietary inhibition of XO protects against radiation-induced vascular injury. We exposed 4-mo-old rats to a single dose of 0 or 5 Gy gamma radiation. These rats received normal drinking water or water containing 1 mM oxypurinol, an XO inhibitor. We measured XO activity and superoxide production in rat aorta and demonstrated that both were significantly elevated 2 wk after radiation exposure. However, oxypurinol treatment in irradiated rats prevented aortic XO activation and superoxide elevation. We next investigated endothelial function through fluorescent measurement of nitric oxide (NO) and vascular tension dose responses. Radiation reduced endothelium-dependent NO production in rat aorta. Similarly, endothelium-dependent vasorelaxation in the aorta of irradiated rats was significantly attenuated compared with the control group. Dietary XO inhibition maintained NO production at control levels and prevented the development of endothelial dysfunction. Furthermore, pulse wave velocity, a measure of vascular stiffness, increased by 1 day postirradiation and remained elevated 2 wk after irradiation, despite unchanged blood pressures. In oxypurinol-treated rats, pulse wave velocities remained unchanged from baseline throughout the experiment, signifying preserved vascular health. These findings demonstrate that XO inhibition can offer protection from radiation-induced endothelial dysfunction and cardiovascular complications.

  5. Inhibition of constitutive endothelial NO-synthase activity by tannin and quercetin.

    PubMed

    Chiesi, M; Schwaller, R

    1995-02-14

    The effect of natural polyphenols on three isoforms of NO-synthase was investigated. Among the compounds tested, tannin was the most potent, inhibiting endothelial constitutive NO synthase (eNOS) with an IC50 of 2.2 microM. Other NOS isoforms (i.e. neuronal constitutive NOS and smooth muscle inducible NOS) were also inhibited but at much higher concentrations (selectivity ratio of approx. 20-30). Quercetin was also an effective but less potent inhibitor of eNOS (IC50 = 220 microM). The kinetics of tannin inhibition were investigated to gather information on the mechanism of action. Tannin did not interfere with the interaction of the enzyme with the co-substrates L-arginine and NADPH nor with the cofactor tetrahydrobiopterin. The inhibition level was also independent of free Ca2+ concentration as well as of the presence of high exogenous calmodulin concentrations.

  6. Protective effect of silymarin against rapamycin-induced apoptosis and proliferation inhibition in endothelial progenitor cells.

    PubMed

    Zhang, Peng; Han, Guohua; Gao, Pei; Qiao, Kun; Ren, Yusheng; Liang, Chun; Leng, Bing; Wu, Zonggui

    2015-02-01

    For this study, peripheral blood samples were collected from human volunteers. Mononuclear cells (MNC) were separated by density centrifugation and were induced to differentiate into endothelial progenitor cells (EPCs) in vitro. Different concentrations of rapamycin and silymarin were introduced to the EPCs over 24 hours and then EPCs were analyzed for proliferation, migration, apoptosis and angiogenesis. Compared with the control group, rapamycin (1, 10, 100 ng/mL) inhibited the proliferation and migration of EPCs in a concentration dependent manner (P<0.05). Silymarin (50, 100 μg/mL) enhanced the proliferation and migration of EPCs and inhibited apoptosis in a concentration dependent manner (P<0.05). By adding rapamycin (1 ng/mL) and silymarin (25, 50, 100 μg/mL) over 24 hours, silymarin inhibited the pro-apoptotic effect of rapamycin on EPCs, and reversed the inhibition of proliferation, migration and angiogenesis of EPCs by rapamycin (P<0.05).

  7. Tissue-engineered endothelial cell layers on surface-modified Ti for inhibiting in vitro platelet adhesion

    NASA Astrophysics Data System (ADS)

    Wang, Xiupeng; He, Fupo; Li, Xia; Ito, Atsuo; Sogo, Yu; Maruyama, Osamu; Kosaka, Ryo; Ye, Jiandong

    2013-06-01

    A tissue-engineered endothelial layer was prepared by culturing endothelial cells on a fibroblast growth factor-2 (FGF-2)-l-ascorbic acid phosphate magnesium salt n-hydrate (AsMg)-apatite (Ap) coated titanium plate. The FGF-2-AsMg-Ap coated Ti plate was prepared by immersing a Ti plate in supersaturated calcium phosphate solutions supplemented with FGF-2 and AsMg. The FGF-2-AsMg-Ap layer on the Ti plate accelerated proliferation of human umbilical vein endothelial cells (HUVECs), and showed slightly higher, but not statistically significant, nitric oxide release from HUVECs than on as-prepared Ti. The endothelial layer maintained proper function of the endothelial cells and markedly inhibited in vitro platelet adhesion. The tissue-engineered endothelial layer formed on the FGF-2-AsMg-Ap layer is promising for ameliorating platelet activation and thrombus formation on cardiovascular implants.

  8. Targeting endothelial connexin40 inhibits tumor growth by reducing angiogenesis and improving vessel perfusion

    PubMed Central

    Alonso, Florian; Domingos-Pereira, Sonia; Le Gal, Loïc; Derré, Laurent; Meda, Paolo; Jichlinski, Patrice; Nardelli-Haefliger, Denise; Haefliger, Jacques-Antoine

    2016-01-01

    Endothelial connexin40 (Cx40) contributes to regulate the structure and function of vessels. We have examined whether the protein also modulates the altered growth of vessels in tumor models established in control mice (WT), mice lacking Cx40 (Cx40−/−), and mice expressing the protein solely in endothelial cells (Tie2-Cx40). Tumoral angiogenesis and growth were reduced, whereas vessel perfusion, smooth muscle cell (SMC) coverage and animal survival were increased in Cx40−/− but not Tie2-Cx40 mice, revealing a critical involvement of endothelial Cx40 in transformed tissues independently of the hypertensive status of Cx40−/− mice. As a result, Cx40−/− mice bearing tumors survived significantly longer than corresponding controls, including after a cytotoxic administration. Comparable observations were made in WT mice injected with a peptide targeting Cx40, supporting the Cx40 involvement. This involvement was further confirmed in the absence of Cx40 or by peptide-inhibition of this connexin in aorta-sprouting, matrigel plug and SMC migration assays, and associated with a decreased expression of the phosphorylated form of endothelial nitric oxide synthase. The data identify Cx40 as a potential novel target in cancer treatment. PMID:26883111

  9. Coniferyl Aldehyde Attenuates Radiation Enteropathy by Inhibiting Cell Death and Promoting Endothelial Cell Function

    PubMed Central

    Son, Yeonghoon; Jang, Jun-Ho; Lee, Yoon-Jin; Kim, Sung-Ho; Ko, Young-Gyo; Lee, Yun-Sil; Lee, Hae-June

    2015-01-01

    Radiation enteropathy is a common complication in cancer patients. The aim of this study was to investigate whether radiation-induced intestinal injury could be alleviated by coniferyl aldehyde (CA), an HSF1-inducing agent that increases cellular HSP70 expression. We systemically administered CA to mice with radiation enteropathy following abdominal irradiation (IR) to demonstrate the protective effects of CA against radiation-induced gastrointestinal injury. CA clearly alleviated acute radiation-induced intestinal damage, as reflected by the histopathological data and it also attenuated sub-acute enteritis. CA prevented intestinal crypt cell death and protected the microvasculature in the lamina propria during the acute and sub-acute phases of damage. CA induced HSF1 and HSP70 expression in both intestinal epithelial cells and endothelial cells in vitro. Additionally, CA protected against not only the apoptotic cell death of both endothelial and epithelial cells but also the loss of endothelial cell function following IR, indicating that CA has beneficial effects on the intestine. Our results provide novel insight into the effects of CA and suggest its role as a therapeutic candidate for radiation-induced enteropathy due to its ability to promote rapid re-proliferation of the intestinal epithelium by the synergic effects of the inhibition of cell death and the promotion of endothelial cell function. PMID:26029925

  10. Coniferyl aldehyde attenuates radiation enteropathy by inhibiting cell death and promoting endothelial cell function.

    PubMed

    Jeong, Ye-Ji; Jung, Myung Gu; Son, Yeonghoon; Jang, Jun-Ho; Lee, Yoon-Jin; Kim, Sung-Ho; Ko, Young-Gyo; Lee, Yun-Sil; Lee, Hae-June

    2015-01-01

    Radiation enteropathy is a common complication in cancer patients. The aim of this study was to investigate whether radiation-induced intestinal injury could be alleviated by coniferyl aldehyde (CA), an HSF1-inducing agent that increases cellular HSP70 expression. We systemically administered CA to mice with radiation enteropathy following abdominal irradiation (IR) to demonstrate the protective effects of CA against radiation-induced gastrointestinal injury. CA clearly alleviated acute radiation-induced intestinal damage, as reflected by the histopathological data and it also attenuated sub-acute enteritis. CA prevented intestinal crypt cell death and protected the microvasculature in the lamina propria during the acute and sub-acute phases of damage. CA induced HSF1 and HSP70 expression in both intestinal epithelial cells and endothelial cells in vitro. Additionally, CA protected against not only the apoptotic cell death of both endothelial and epithelial cells but also the loss of endothelial cell function following IR, indicating that CA has beneficial effects on the intestine. Our results provide novel insight into the effects of CA and suggest its role as a therapeutic candidate for radiation-induced enteropathy due to its ability to promote rapid re-proliferation of the intestinal epithelium by the synergic effects of the inhibition of cell death and the promotion of endothelial cell function.

  11. Endothelin-1 inhibits endothelin-converting enzyme-1 expression in cultured rat pulmonary endothelial cells.

    PubMed

    Naomi, S; Iwaoka, T; Disashi, T; Inoue, J; Kanesaka, Y; Tokunaga, H; Tomita, K

    1998-01-27

    The lung expresses large amounts of endothelin-converting enzyme-1 (ECE-1), which catalyzes a step in the biosynthesis of potent vasoactive endothelin-1 (ET-1) from the inactive intermediate big ET-1. Because there has been no report concerning a possible relationship between ET-1 and ECE-1, we investigated the effects of ET-1 on ECE-1 expression in cultured rat pulmonary endothelial cells. ECE-1 messenger RNA (mRNA) and protein expression in cultured endothelial cells were assayed by Northern and Western blotting, respectively. Incubation with ET-1 for 6 hours caused a significant decrease in ECE-1 mRNA expression. The action of ET-1 on ECE-1 mRNA expression was antagonized by pretreatment with BQ788, a specific ETB receptor antagonist, but not by pretreatment with BQ123, a specific ETA receptor antagonist. The expression of ECE-1 protein was also inhibited at 6 hours after incubation with ET-1. The effects of ET-1 on ECE-1 mRNA and protein expression were shown to be mimicked by ionomycin, a calcium ionophore, but not by 12-O-tetradecanoylphorbol 13-acetate, a protein kinase C activator. The present results demonstrate that ET-1 suppressed ECE-1 protein levels by inhibiting ECE-1 mRNA expression through the ETB receptor, suggesting the existence of a feedback action of ET-1 on ECE-1 in pulmonary endothelial cells.

  12. Jin Fu Kang Oral Liquid Inhibits Lymphatic Endothelial Cells Formation and Migration

    PubMed Central

    Wang, Dan; Tang, Jie

    2016-01-01

    Lung cancer is the leading cause of cancer-related deaths worldwide. Jin Fu Kang (JFK), an oral liquid prescription of Chinese herbal drugs, has been clinically available for the treatment of non-small cell lung cancer (NSCLC). Lymphangiogenesis is a primary event in the process of cancer development and metastasis, and the formation and migration of lymphatic endothelial cells (LECs) play a key role in the lymphangiogenesis. To assess the activity of stromal cell-derived factor-1 (SDF-1) and the coeffect of SDF-1 and vascular endothelial growth factor-C (VEGF-C) on the formation and migration of LECs and clarify the inhibitory effects of JFK on the LECs, the LECs were differentiated from CD34+/VEGFR-3+ endothelial progenitor cells (EPCs), and JFK-containing serums were prepared from rats. SDF-1 and VEGF-C both induced the differentiation of CD34+/VEGFR-3+ EPCs towards LECs and enhanced the LECs migration. Couse of SDF-1 and VEGF-C displayed an additive effect on the LECs formation but not on their migration. JFK inhibited the formation and migration of LECs, and the inhibitory effects were most probably via regulation of the SDF-1/CXCR4 and VEGF-C/VEGFR-3 axes. The current finding suggested that JFK might inhibit NSCLC through antilymphangiogenesis and also provided a potential to discover antilymphangiogenesis agents from natural resources. PMID:27698675

  13. Sodium caffeate induces endothelial cell apoptosis and inhibits VEGF expression in cancer cells.

    PubMed

    Xu, Feng; Ou-Yang, Zhi-Gang; Zhang, Sheng-Hua; Song, Dan-Qing; Shao, Rong-Guang; Zhen, Yong-Su

    2006-06-01

    To investigate the induction of endothelial cell apoptosis and the suppression of VEGF expression in cancer cells by sodium caffeate (SCA). Apoptosis of transformed human umbilical vein endothelial cells (ECV304 cell line) was detected by flow cytometry, DNA electrophoresis assay and morphological assessment. Western blotting analysis was applied for determination of VEGF expression in cancer cells. Substrate degradation by type IV collagenase was measured by zymography. ELISA was used to detect the binding of type IV collagenase with relevant monoclonal antibody. SCA induced ECV304 cell apoptosis in a time- and dose-dependent manner. After treatment with 100 and 250 microg X mL(-1) of SCA for 48 h, DNA laddering appeared. SCA treated cells showed strong blue fluorescence and distinct changes of nuclear morphology, such as pyknosis and the occurrence of apoptotic bodies. VEGF expression in hepatoma HepG-2 cells and prostate carcinoma DU145 cells was reduced after SCA treatment. The degradation activity of type IV collagenase including MMP-2 and MMP-9 secreted by giant cell pulmonary carcinoma PG cells was inhibited by SCA in a dose-dependent manner. SCA also reduced the binding of mAb 3D6, a relevant monoclonal antibody, to type IV collagenase. SCA can induce endothelial cell apoptosis and inhibit VEGF expression as well as type IV collagenase activity in cancer cells. SCA might be active in modulating tumor angiogenesis and the microenvironment.

  14. Antiangiogenic potential of grape stem extract through inhibition of vascular endothelial growth factor expression.

    PubMed

    Stagos, D; Apostolou, A; Poulios, E; Kermeliotou, E; Mpatzilioti, A; Kreatsouli, K; Koulocheri, S D; Haroutounian, S A; Kouretas, D

    2014-12-01

    The aim of the present study was to investigate the antiangiogenic potential of a grape stem extract against tube formation by human endothelial cells (EA.hy926). The results showed that at low and non-cytotoxic concentrations (50 and 100 μg/ml) the grape stem extract inhibited tube formation, indicating a possible antiangiogenic activity. Moreover, the results showed that this extract inhibited the expression levels of vascular endothelial growth factor (VEGF), one of the most potent proangiogenic factors, suggesting that the tube formation inhibition by the extract may be exerted through inhibition of VEGF levels. Since it is well established that VEGF prevents apoptosis, the previous finding was further supported by the fact that the grape stem extract induced apoptosis in EA.hy926 cells. Furthermore, it was shown that the extract treatment did not change the levels of the proangiogenic molecules hypoxia inducible factor 1 alpha (HIF-1α) and cyclooxygenase-1 (COX-1). Therefore, these findings indicate that the grape stem extract reduces VEGF levels through mechanisms that may be HIF-1α- and COX-1-independent. The present study is the first showing that grape stem extracts possess antiangiogenic potential. Thus, our findings suggest that since grape stem extracts possess important bioactivities such as antiangiogenic potential, they could be exploited for developing chemopreventive and anticancer agents, while simultaneously protecting the environment through the use of a harmful waste.

  15. G protein-coupled receptor 183 facilitates endothelial-to-hematopoietic transition via Notch1 inhibition.

    PubMed

    Zhang, Panpan; He, Qiuping; Chen, Dongbo; Liu, Weixiao; Wang, Lu; Zhang, Chunxia; Ma, Dongyuan; Li, Wei; Liu, Bing; Liu, Feng

    2015-10-01

    In vertebrates, embryonic hematopoietic stem and progenitor cells (HSPCs) are derived from a subset of endothelial cells, the hemogenic endothelium (HE), through the endothelial-to-hematopoietic transition (EHT). Notch signaling is essential for HSPC development during embryogenesis across vertebrates. However, whether and how it regulates EHT remains unclear. Here, we show that G protein-coupled receptor 183 (Gpr183) signaling serves as an indispensable switch for HSPC emergence by repressing Notch signaling before the onset of EHT. Inhibition of Gpr183 significantly upregulates Notch signaling and abolishes HSPC emergence. Upon activation by its ligand 7α-25-OHC, Gpr183 recruits β-arrestin1 and the E3 ligase Nedd4 to degrade Notch1 in specified HE cells and then facilitates the subsequent EHT. Importantly, 7α-25-OHC stimulation promotes HSPC emergence in vivo and in vitro, providing an attractive strategy for enhancing the in vitro generation of functional HSPCs.

  16. Olive oil compounds inhibit vascular endothelial growth factor receptor-2 phosphorylation

    SciTech Connect

    Lamy, Sylvie Ouanouki, Amira; Béliveau, Richard; Desrosiers, Richard R.

    2014-03-10

    Vascular endothelial growth factor (VEGF) triggers crucial signaling processes that regulate tumor angiogenesis and, therefore, represents an attractive target for the development of novel anticancer therapeutics. Several epidemiological studies have confirmed that abundant consumption of foods from plant origin is associated with reduced risk of developing cancers. In the Mediterranean basin, the consumption of extra virgin olive oil is an important constituent of the diet. Compared to other vegetable oils, the presence of several phenolic antioxidants in olive oil is believed to prevent the occurrence of a variety of pathological processes, such as cancer. While the strong antioxidant potential of these molecules is well characterized, their antiangiogenic activities remain unknown. The aim of this study is to investigate whether tyrosol (Tyr), hydroxytyrosol (HT), taxifolin (Tax), oleuropein (OL) and oleic acid (OA), five compounds contained in extra virgin olive oil, can affect in vitro angiogenesis. We found that HT, Tax and OA were the most potent angiogenesis inhibitors through their inhibitory effect on specific autophosphorylation sites of VEGFR-2 (Tyr951, Tyr1059, Tyr1175 and Tyr1214) leading to the inhibition of endothelial cell (EC) signaling. Inhibition of VEGFR-2 by these olive oil compounds significantly reduced VEGF-induced EC proliferation and migration as well as their morphogenic differentiation into capillary-like tubular structures in Matrigel. Our study demonstrates that HT, Tax and OA are novel and potent inhibitors of the VEGFR-2 signaling pathway. These findings emphasize the chemopreventive properties of olive oil and highlight the importance of nutrition in cancer prevention. - Highlights: • We investigated five compounds contained in extra virgin olive oil on angiogenesis. • Hydroxytyrosol, taxifolin and oleic acid are the best angiogenesis inhibitors. • Olive oil compounds affect endothelial cell functions essential for

  17. MC-002 exhibits positive effects against platelets aggregation and endothelial dysfunction through thromboxane A2 inhibition.

    PubMed

    Fang, Weirong; Wei, Jie; Han, Dan; Chen, Xi; He, Guangwei; Wu, Qiang; Chu, Shaoxing; Li, Yunman

    2014-04-01

    Thromboxane A2 (TXA2) induces platelet aggregation and vasoconstriction, and agents that inhibit TXA2 production or interaction with receptors may exert potential application in stroke therapy. To illustrate the platelet aggregation antagonistic and endothelial protective effect of (E) - 3 - (3 - methoxy - 4 - ((3, 5, 6 - trimethylpyrazin - 2 - yl) methoxy) phenyl) sodium acrylate (MC-002) through TXA2 inhibition and underline mechanisms. Platelets aggregation and thoracic aorta ring contraction of rabbits were induced by U46619. Human umbilical vein endothelial cells (HUVECs) were further applied to explore the protective effect of MC-002 on endothelium when exposed to tumor necrosis factor - α (TNF-α). MTT method was used to assess cell damage, and ELISA analysis was exerted to estimate nitrogen monoxide (NO), endothelin-1 (ET-1), thromboxane B2 (TXB2) and 6-keto-prostaglandin F1α (6-keto-PGF1α) releasing. Fluorescence spectrophotometry was conducted to determine intracellular calcium concentration ([Ca(2+)]i), and western blotting method was applied to evaluate the protein expressions of intracellular adhesion molecule-1 (ICAM-1), P-selectin and nuclear factor-kappa B (NF-κB). TXA2 analog U46619 mediated obvious platelet aggregation and vasoconstriction. MC-002 inhibited platelet aggregation through administration in vivo and incubation with platelet in vitro, and relaxed aorta ring in endothelium dependent manner. MC-002 alleviated cell damage, [Ca(2+)]i overload, ET-1 overexcretion and TXB2 activation, but improved NO availability reduction in HUVECs treated with TNF-α. Furthermore, MC-002 downregulated ICAM-1, P-selectin and NF-κB overexpression induced by TNF-α. In conclusion, MC-002 exerted antiplatelet aggregation effect through TXA2 inhibition and relieved inflammatory injury of endothelial cells through NF-κB signal pathway. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Grape seed extract inhibits angiogenesis via suppression of the vascular endothelial growth factor receptor signaling pathway.

    PubMed

    Wen, Wei; Lu, Jianming; Zhang, Keqiang; Chen, Shiuan

    2008-12-01

    Blockade of angiogenesis is an important approach for cancer treatment and prevention. Vascular endothelial growth factor (VEGF) is one of the most critical factors that induce angiogenesis and has thus become an attractive target for antiangiogenesis treatment. However, most current anti-VEGF agents often cause some side effects when given chronically. Identification of naturally occurring VEGF inhibitors derived from diet would be one alternative approach with an advantage of known safety. Grape seed extract (GSE), a widely used dietary supplement, is known to have antitumor activity. In this study, we have explored the activity of GSE on VEGF receptor and angiogenesis. We found that GSE could directly inhibit the kinase activity of purified VEGF receptor 2, a novel activity of GSE that has not been characterized. GSE could also inhibit the VEGF receptor/mitogen-activated protein kinase-mediated signaling pathway in endothelial cells. As a result, GSE could inhibit VEGF-induced endothelial cell proliferation and migration as well as sprout formation from aorta ring. In vivo assay further showed that GSE could inhibit tumor growth and tumor angiogenesis of MDA-MB-231 breast cancer cells in mice. Consistent with the in vitro data, GSE treatment of tumor-bearing mice led to concomitant reduction of blood vessel density and phosphorylation of mitogen-activated protein kinase. Depletion of polyphenol with polyvinylpyrrolidone abolished the antiangiogenic activity of GSE, suggesting a water-soluble fraction of polyphenol in GSE is responsible for the antiangiogenic activity. Taken together, this study indicates that GSE is a well-tolerated and inexpensive natural VEGF inhibitor and could potentially be useful in cancer prevention or treatment.

  19. VEGF-B gene therapy inhibits doxorubicin-induced cardiotoxicity by endothelial protection

    PubMed Central

    Räsänen, Markus; Degerman, Joni; Nissinen, Tuuli A.; Miinalainen, Ilkka; Kerkelä, Risto; Siltanen, Antti; Backman, Janne T.; Mervaala, Eero; Hulmi, Juha J.; Kivelä, Riikka; Alitalo, Kari

    2016-01-01

    Congestive heart failure is one of the leading causes of disability in long-term survivors of cancer. The anthracycline antibiotic doxorubicin (DOX) is used to treat a variety of cancers, but its utility is limited by its cumulative cardiotoxicity. As advances in cancer treatment have decreased cancer mortality, DOX-induced cardiomyopathy has become an increasing problem. However, the current means to alleviate the cardiotoxicity of DOX are limited. We considered that vascular endothelial growth factor-B (VEGF-B), which promotes coronary arteriogenesis, physiological cardiac hypertrophy, and ischemia resistance, could be an interesting candidate for prevention of DOX-induced cardiotoxicity and congestive heart failure. To study this, we administered an adeno-associated viral vector expressing VEGF-B or control vector to normal and tumor-bearing mice 1 wk before DOX treatment, using doses mimicking the concentrations used in the clinics. VEGF-B treatment completely inhibited the DOX-induced cardiac atrophy and whole-body wasting. VEGF-B also prevented capillary rarefaction in the heart and improved endothelial function in DOX-treated mice. VEGF-B also protected cultured endothelial cells from apoptosis and restored their tube formation. VEGF-B increased left ventricular volume without compromising cardiac function, reduced the expression of genes associated with pathological remodeling, and improved cardiac mitochondrial respiration. Importantly, VEGF-B did not affect serum or tissue concentrations of DOX or augment tumor growth. By inhibiting DOX-induced endothelial damage, VEGF-B could provide a novel therapeutic possibility for the prevention of chemotherapy-associated cardiotoxicity in cancer patients. PMID:27799559

  20. Benidipine, a dihydropyridine-calcium channel blocker, inhibits lysophosphatidylcholine-induced endothelial injury via stimulation of nitric oxide release.

    PubMed

    Matsubara, Masahiro; Yao, Kozo; Hasegawa, Kazuhide

    2006-01-01

    Benidipine hydrochloride (benidipine), which is a long-lasting dihydropyridine calcium channel blocker, exerts antihypertensive action via inhibition of Ca(2+) influx through L-type voltage-dependent calcium channels. In addition, benidipine is shown to restore endothelial function. However, the mechanisms whereby benidipine has protective effects on endothelium are poorly defined. Nitric oxide (NO), which is produced by endothelial NO synthase (eNOS), plays important roles in endothelial function. In this study, we examined effects of benidipine on NO production from human umbilical vein endothelial cells. Benidipine (0.3-10 microM) augmented eNOS expression and total eNOS enzymatic activities. Benidipine also promoted the production of NO and the accumulation of cGMP, a second messenger of NO. Lysophosphatidylcholine (lysoPC), a component of oxidized low-density lipoproteins, induced caspase-3 activation followed by apoptosis of endothelial cells. Benidipine (0.3-10 microM) prevented lysoPC-induced caspase-3 activation, which was canceled by Nomega-nitro-L-arginine-methyl ester (L-NAME) (250-2500 microM), an inhibitor of NOS. Moreover, diethylenetetraamine NONOate (30-100 microM), a NO donor, inhibited the caspase-3 activation. These results suggested that the increase in NO production by benidipine might be involved in the inhibition of caspase induction. The direct enhancement of endothelial NO release by benidipine may be in part responsible for amelioration of endothelial dysfunction.

  1. Selective HDAC6 inhibition prevents TNF-α-induced lung endothelial cell barrier disruption and endotoxin-induced pulmonary edema.

    PubMed

    Yu, Jinyan; Ma, Zhongsen; Shetty, Sreerama; Ma, Mengshi; Fu, Jian

    2016-07-01

    Lung endothelial damage contributes to the pathogenesis of acute lung injury. New strategies against lung endothelial barrier dysfunction may provide therapeutic benefits against lung vascular injury. Cell-cell junctions and microtubule cytoskeleton are basic components in maintaining endothelial barrier integrity. HDAC6, a deacetylase primarily localized in the cytoplasm, has been reported to modulate nonnuclear protein function through deacetylation. Both α-tubulin and β-catenin are substrates for HDAC6. Here, we examined the effects of tubastatin A, a highly selective HDAC6 inhibitor, on TNF-α induced lung endothelial cell barrier disruption and endotoxin-induced pulmonary edema. Selective HDAC6 inhibition by tubastatin A blocked TNF-α-induced lung endothelial cell hyperpermeability, which was associated with increased α-tubulin acetylation and microtubule stability. Tubastatin A pretreatment inhibited TNF-α-induced endothelial cell contraction and actin stress fiber formation with reduced myosin light chain phosphorylation. Selective HDAC6 inhibition by tubastatin A also induced β-catenin acetylation in human lung endothelial cells, which was associated with increased membrane localization of β-catenin and stabilization of adherens junctions. HDAC6 knockdown by small interfering RNA also prevented TNF-α-induced barrier dysfunction and increased α-tubulin and β-catenin acetylation in endothelial cells. Furthermore, in a mouse model of endotoxemia, tubastatin A was able to prevent endotoxin-induced deacetylation of α-tubulin and β-catenin in lung tissues, which was associated with reduced pulmonary edema. Collectively, our data indicate that selective HDAC6 inhibition by tubastatin A is a potent approach against lung endothelial barrier dysfunction.

  2. PGC-1-related coactivator (PRC) negatively regulates endothelial adhesion of monocytes via inhibition of NF κB activity

    SciTech Connect

    Chengye, Zhan; Daixing, Zhou Qiang, Zhong; Shusheng, Li

    2013-09-13

    Highlights: •First time to display that LPS downregulate the expression of PRC. •First time to show that PRC inhibits the induction of VCAM-1 and E-selectin. •First time to show that PRC inhibit monocytes attachment to endothelial cells. •First time to display that PRC inhibits transcriptional activity of NF-κB. •PRC protects the respiration rate and suppresses the glycolysis rate against LPS. -- Abstract: PGC-1-related coactivator (PRC) is a growth-regulated transcriptional cofactor known to activate many of the nuclear genes specifying mitochondrial respiratory function. Endothelial dysfunction is a prominent feature found in many inflammatory diseases. Adhesion molecules, such as VCAM-1, mediate the attachment of monocytes to endothelial cells, thereby playing an important role in endothelial inflammation. The effects of PRC in regards to endothelial inflammation remain unknown. In this study, our findings show that PRC can be inhibited by the inflammatory cytokine LPS in cultured human umbilical vein endothelial cells (HUVECs). In the presence of LPS, the expression of endothelial cell adhesion molecular, such as VCAM1 and E-selectin, is found to be increased. These effects can be negated by overexpression of PRC. Importantly, monocyte adhesion to endothelial cells caused by LPS is significantly attenuated by PRC. In addition, overexpression of PRC protects mitochondrial metabolic function and suppresses the rate of glycolysis against LPS. It is also found that overexpression of PRC decreases the transcriptional activity of NF-κB. These findings suggest that PRC is a negative regulator of endothelial inflammation.

  3. Notch4-induced inhibition of endothelial sprouting requires the ankyrin repeats and involves signaling through RBP-Jkappa.

    PubMed

    MacKenzie, Farrell; Duriez, Patrick; Larrivée, Bruno; Chang, Linda; Pollet, Ingrid; Wong, Fred; Yip, Calvin; Karsan, Aly

    2004-09-15

    Notch proteins comprise a family of transmembrane receptors. Ligand activation of Notch releases the intracellular domain of the receptor that translocates to the nucleus and regulates transcription through the DNA-binding protein RBP-Jkappa. Previously, it has been shown that the Notch4 intracellular region (N4IC) can inhibit endothelial sprouting and angiogenesis. Here, N4IC deletion mutants were assessed for their ability to inhibit human microvascular endothelial cell (HMEC) sprouting with the use of a quantitative endothelial sprouting assay. Deletion of the ankyrin repeats, but not the RAM (RBP-Jkappa associated module) domain or C-terminal region (CT), abrogated the inhibition of fibroblast growth factor 2 (FGF-2)- and vascular endothelial growth factor (VEGF)-induced sprouting by Notch4, whereas the ankyrin repeats alone partially blocked sprouting. The ankyrin repeats were also the only domain required for up-regulation of RBP-Jkappa-dependent gene expression. Interestingly, enforced expression of the ankyrin domain alone was sufficient to up-regulate some, but not all, RBP-Jkappa-dependent genes. Although N4IC reduced VEGF receptor-2 (VEGFR-2) and vascular endothelial (VE)-cadherin expression, neither of these events is necessary and sufficient to explain N4IC-mediated inhibition of sprouting. A constitutively active RBP-Jkappa mutant significantly inhibited HMEC sprouting but not as strongly as N4IC. Thus, Notch4-induced inhibition of sprouting requires the ankyrin repeats and appears to involve RBP-Jkappa-dependent and -independent signaling.

  4. Aspirin inhibits interleukin 1-induced prostaglandin H synthase expression in cultured endothelial cells

    SciTech Connect

    Wu, K.K.; Sanduja, R.; Tsai, A.L.; Ferhanoglu, B.; Loose-Mitchell, D.S. )

    1991-03-15

    Prostaglandin H (PGH) synthase is a key enzyme in the biosynthesis of prostaglandins, thromboxane, and prostacyclin. In cultured human umbilical vein endothelial cells, interleukin 1 (IL-1) is known to induce the synthesis of this enzyme, thereby raising the level of PGH synthase protein severalfold over the basal level. Pretreatment with aspirin at low concentrations inhibited more than 60% of the enzyme mass and also the cyclooxygenase activity in IL-1-induced cells with only minimal effects on the basal level of the synthase enzyme in cells without IL-1. Sodium salicylate exhibited a similar inhibitory action whereas indomethacin had no apparent effect. Similarly low levels of aspirin inhibited the increased L-({sup 35}S)methionine incorporation into PGH synthase that was induced by IL0-1 and also suppressed expression of the 2.7-kilobase PGH synthase mRNA. These results suggest that in cultured endothelial cells a potent inhibition of eicosanoid biosynthetic capacity can be effected by aspirin or salicylate at the level of PGH synthase gene expression. The aspirin effect may well be due to degradation of salicylate.

  5. Curcumin attenuates endothelial cell oxidative stress injury through Notch signaling inhibition.

    PubMed

    Yang, Yang; Duan, Weixun; Liang, Zhenxin; Yi, Wei; Yan, Juanjuan; Wang, Ning; Li, Yue; Chen, Wensheng; Yu, Shiqiang; Jin, Zhenxiao; Yi, Dinghua

    2013-03-01

    Previous studies have demonstrated that Notch signaling pathway plays a regulatory role in cellular oxidative stress injury (OSI). In this study, our aim was to explore the role of the Notch signaling pathway in hydrogen peroxide (H(2)O(2))-induced OSI and the protective effect of curcumin during (H(2)O(2))-induced injury in human umbilical vein endothelial cells (HUVECs). DAPT, a specific inhibitor of the Notch signaling pathway, and Notch1 siRNA were used to study Notch activity. Further, HUVECs were exposed to H(2)O(2) in the absence or presence of curcumin. DAPT and Notch1 siRNA significantly inhibited OSI and the expression of Notch1 and Hes1. Curcumin conferred a protective effect on the HUVECs against H(2)O(2), which was evidenced by improved cell viability, adhesive ability and migratory ability and a decreased apoptotic index, decreased production of reactive oxygen species (ROS) and a reduction in several biochemical parameters. Immunofluorescence and Western blotting analyses demonstrated that H(2)O(2) treatment upregulated the expression of Notch1, Hes1, Caspase3, Bax and cytochrome c downregulated the expression of Bcl2, and treatment with curcumin reversed these effects. We demonstrated for the first time that the inhibition of Notch signaling pathway imparts a protective effect against endothelial OSI. The protective effects of curcumin against OSI are at least in part dependent on Notch1 inhibition.

  6. Recombinant human vascular endothelial growth factor receptor 1 effectively inhibits angiogenesis in vivo.

    PubMed

    Wang, Jinliang; Shi, Minglei; Xi, Yongyi; Gao, Lihua; Zhang, Guanyi; Shao, Yong; Chen, Huipeng; Hu, Xianwen

    2015-05-01

    Vascular endothelial growth factor (VEGF) plays an important role in both physiological and pathological angiogenesis. VEGF receptor‑1 (VEGFR‑1) acts as a decoy VEGF receptor that enables the regulation of VEGF on the vascular endothelium. In the present study, the recombinant human VEGFR1D1‑3/Fc (rhVEGFR‑1), which contains key domains for VEGF binding, was cloned and expressed in Chinese hamster ovary (CHO) cells. The rhVEGFR‑1 protein was purified using protein‑A affinity chromatography. The molecular weight of rhVEGFR‑1 was found to be ~162 and 81 kD in non‑reducing and reducing SDS‑PAGE, respectively. The majority of the final protein products were in the dimeric conformation. Western blot analysis revealed that rhVEGFR‑1 was only capable of binding to the full glycan form of rhVEGF‑165 and rhVEGF‑121. The dissociation constant for the binding of rhVEGFR‑1 to VEGF‑165, detected using Biacore, was 285 pM. In addition, rhVEGFR‑1 inhibited the proliferation and migration of human microvascular endothelial cells. In vivo experiments also demonstrated that rhVEGFR‑1 inhibited chicken chorioallantoic membrane neovascularization and angiogenesis in nude mice. In conclusion, an anti‑angiogenic recombinant soluble VEGFR was expressed (up to 5 mg/l) in CHO cells and was shown to be capable of inhibiting neovascularization in vivo and in vitro.

  7. High concentration of glucose inhibits glomerular endothelial eNOS through a PKC mechanism.

    PubMed

    Chu, Shaoyou; Bohlen, H Glenn

    2004-09-01

    Kidney glomeruli are important targets of diabetic nephropathy. We hypothesized a high concentration of glucose could suppress glomerular endothelial nitric oxide synthase (eNOS) by a protein kinase C (PKC) mechanism, as has been found in other tissues. Mouse kidney slices (150-200 microm) were bathed in Hanks' solution with 100 microM L-arginine and exposed to either 5 or 20-30 mM D-glucose. Immunofluorescence identified only eNOS in normal mouse glomeruli. Measurements of glomerular NO concentration with NO-sensitive fluorescent dye (4,5-diaminofluorescein diacetate) using confocal microscopy and NO-sensitive microelectrodes verified that resting glomeruli had active production of NO that was inhibited by N(G)-nitro-L-arginine methyl ester. High-concentration (20-30 mM) D-glucose inhibited 60-70% of the NO production within 15-30 min; L-glucose at the same concentration did not have any effect. Inhibition of PKC-beta with 100 nM ruboxistaurin prevented eNOS suppression in high-glucose media. Activation of PKC with 100 nM phorbol ester also suppressed the glomerular NO concentration. We concluded that eNOS in the renal glomerular capillary endothelial cells is suppressed by activity of PKC at high-glucose concentrations comparable to those in diabetic animals and humans. The consequence is a rapid decline in the generation of NO in the glomerular endothelial cells in the presence of a high concentration of glucose.

  8. Simvastatin combined with nifedipine enhances endothelial cell protection by inhibiting ROS generation and activating Akt phosphorylation

    PubMed Central

    Chen, Xiao-niao; Xu, Jun; Feng, Zhe; Fan, Ming; Han, Jing-yao; Yang, Zhuo

    2010-01-01

    Aim: To investigate the protective effects of simvastatin (Sim) combined with nifedipine (Nif) on endothelial cells and elucidate the action mechanism. Methods: Human umbilical vein endothelial cells (HUVEC) were used. mRNA and protein levels were measured by using reverse-transcription polymerase chain reaction (RT-PCR) and Western blotting, respectively. Intracellular calcium and reactive oxygen species (ROS) were detected using confocal microscopy. The Griess assay was used to evaluate nitric oxide (NO) release. Results: Treatment of HUVEC with H2O2 100 μmol/L for 30 min inhibited the mRNA and protein expression of endothelial nitric oxide synthase (eNOS). With increased concentrations of Nif, eNOS mRNA and protein levels increased (P<0.05). Combined treatment with Sim 1.0 μmol/L and Nif 1.0 μmol/L significantly increased the mRNA and protein expression of eNOS and NO release compared with Sim or Nif alone (P<0.05). The combination significantly lowered the intracellular ROS level (P<0.05), which was correlated with the increase in eNOS and NO, but there was no visible change in intracellular calcium (P>0.05). Compared with individual drug treatment, Akt phosphorylation and the ratio of p-eNOS/eNOS were up-regulated in the combination group, and this effect was inhibited by the phosphatidylinositol 3-kinase (PI3K) inhibitors wortmannin and LY294002. Conclusion: The Sim-Nif combination effectively protects HUVEC against H2O2 injury by inhibiting intracellular ROS generation, increasing the ratio of p-eNOS/eNOS and up-regulating Akt phosphorylation. PMID:20562903

  9. Dual mechanisms of NF-kappaB inhibition in carnosol-treated endothelial cells

    SciTech Connect

    Lian, K.-C.; Chuang, J.-J.; Hsieh, C.-W.; Wung, B.-S.; Huang, G.-D.; Jian, T.-Y.; Sun, Y.-W.

    2010-05-15

    The increased adhesion of monocytes to injured endothelial layers is a critical early event in atherogenesis. Under inflammatory conditions, there is increased expression of specific cell adhesion molecules on activated vascular endothelial cells, which increases monocyte adhesion. In our current study, we demonstrate a putative mechanism for the anti-inflammatory effects of carnosol, a diterpene derived from the herb rosemary. Our results show that both carnosol and rosemary essential oils inhibit the adhesion of TNFalpha-induced monocytes to endothelial cells and suppress the expression of ICAM-1 at the transcriptional level. Moreover, carnosol was found to exert its inhibitory effects by blocking the degradation of the inhibitory protein IkappaBalpha in short term pretreatments but not in 12 h pretreatments. Our data show that carnosol reduces IKK-beta phosphorylation in pretreatments of less than 3 h. In TNFalpha-treated ECs, NF-kappaB nuclear translocation and transcriptional activity was abolished by up to 12 h of carnosol pretreatment and this was blocked by Nrf-2 siRNA. The long-term inhibitory effects of carnosol thus appear to be mediated through its induction of Nrf-2-related genes. The inhibition of ICAM-1 expression and p65 translocation is reversed by HO-1 siRNA. Carnosol also upregulates the Nrf-2-related glutathione synthase gene and thereby increases the GSH levels after 9 h of exposure. Treating ECs with a GSH synthesis inhibitor, BSO, blocks the inhibitory effects of carnosol. In addition, carnosol increases p65 glutathionylation. Hence, our present findings indicate that carnosol suppresses TNFalpha-induced singling pathways through the inhibition of IKK-beta activity or the upregulation of HO-1 expression. The resulting GSH levels are dependent, however, on the length of the carnosol pretreatment period.

  10. Radiotherapy Suppresses Angiogenesis in Mice through TGF-βRI/ALK5-Dependent Inhibition of Endothelial Cell Sprouting

    PubMed Central

    Imaizumi, Natsuko; Monnier, Yan; Hegi, Monika; Mirimanoff, René-Olivier; Rüegg, Curzio

    2010-01-01

    Background Radiotherapy is widely used to treat cancer. While rapidly dividing cancer cells are naturally considered the main target of radiotherapy, emerging evidence indicates that radiotherapy also affects endothelial cell functions, and possibly also their angiogenic capacity. In spite of its clinical relevance, such putative anti-angiogenic effect of radiotherapy has not been thoroughly characterized. We have investigated the effect of ionizing radiation on angiogenesis using in vivo, ex vivo and in vitro experimental models in combination with genetic and pharmacological interventions. Principal Findings Here we show that high doses ionizing radiation locally suppressed VEGF- and FGF-2-induced Matrigel plug angiogenesis in mice in vivo and prevented endothelial cell sprouting from mouse aortic rings following in vivo or ex vivo irradiation. Quiescent human endothelial cells exposed to ionizing radiation in vitro resisted apoptosis, demonstrated reduced sprouting, migration and proliferation capacities, showed enhanced adhesion to matrix proteins, and underwent premature senescence. Irradiation induced the expression of P53 and P21 proteins in endothelial cells, but p53 or p21 deficiency and P21 silencing did not prevent radiation-induced inhibition of sprouting or proliferation. Radiation induced Smad-2 phosphorylation in skin in vivo and in endothelial cells in vitro. Inhibition of the TGF-β type I receptor ALK5 rescued deficient endothelial cell sprouting and migration but not proliferation in vitro and restored defective Matrigel plug angiogenesis in irradiated mice in vivo. ALK5 inhibition, however, did not rescue deficient proliferation. Notch signaling, known to hinder angiogenesis, was activated by radiation but its inhibition, alone or in combination with ALK5 inhibition, did not rescue suppressed proliferation. Conclusions These results demonstrate that irradiation of quiescent endothelial cells suppresses subsequent angiogenesis and that ALK5 is a

  11. Phagocytosis by macrophages and endothelial cells inhibits procoagulant and fibrinolytic activity of acute promyelocytic leukemia cells.

    PubMed

    Xie, Rui; Gao, Chunyan; Li, Wen; Zhu, Jiuxin; Novakovic, Valerie; Wang, Jing; Ma, Ruishuang; Zhou, Jin; Gilbert, Gary E; Shi, Jialan

    2012-03-08

    The coagulopathy of acute promyelocytic leukemia (APL) is mainly related to procoagulant substances and fibrinolytic activators of APL blasts, but the fate of these leukemic cells is unknown. The aim of this study was to investigate the removal of APL blasts by macrophages and endothelial cells in vitro and consequent procoagulant and fibrinolytic activity of APL cells. We found that human umbilical vein endothelial cells as well as THP-1 and monocyte-derived macrophages bound, engulfed, and subsequently degraded immortalized APL cell line NB4 and primary APL cells. Lactadherin promoted phagocytosis of APL cells in a time-dependent fashion. Furthermore, factor Xa and prothrombinase activity of phosphatidylserine-exposed target APL cells was time-dependently decreased after incubation with phagocytes (THP-1-derived macrophages or HUVECs). Thrombin production on target APL cells was reduced by 40%-45% after 2 hours of coincubation with phagocytes and 80% by a combination of lactadherin and phagocytes. Moreover, plasmin generation of target APL cells was inhibited 30% by 2 hours of phagocytosis and ∼ 50% by lactadherin-mediated engulfment. These results suggest that engulfment by macrophages and endothelial cells reduce procoagulant and fibrinolytic activity of APL blasts. Lactadherin and phagocytosis could cooperatively ameliorate the clotting disorders in APL.

  12. Degradable poly(apigenin) polymer inhibits tumor cell adhesion to vascular endothelial cells.

    PubMed

    Cochran, David B; Gray, Lindsay N; Anderson, Kimberly W; Dziubla, Thomas D

    2016-10-01

    Cancer and the inflammatory system share a complex intertwined relationship. For instance, in response to an injury or stress, vascular endothelial cells will express cell adhesion molecules as a means of recruiting leukocytes. However, circulating tumor cells (CTCs) have been shown to highjack this expression for the adhesion and invasion during the metastatic cascade. As such, the initiation of endothelial cell inflammation, either by surgical procedures (cancer resection) or chemotherapy can inadvertently increase the metastatic potential of CTCs. Yet, systemic delivery of anti-inflammatories, which weaken the entire immune system, may not be preferred in some treatment settings. In this work, we demonstrate that a long-term releasing flavone-based polymer and subsequent nanoparticle delivery system can inhibit tumor cell adhesion, through the suppression of endothelial cell adhesion molecule expression. The degradation of a this anti-inflammatory polymer provides longer term, localized release profile of active therapeutic drug in nanoparticle form as compared with that of the free drug, permitting more targeted anti-metastatic therapies. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1438-1447, 2016.

  13. Adenosine opposes thrombin-induced inhibition of intercellular calcium wave in corneal endothelial cells.

    PubMed

    D'hondt, Catheleyne; Srinivas, Sangly P; Vereecke, Johan; Himpens, Bernard

    2007-04-01

    In corneal endothelial cells, intercellular Ca(2+) waves elicited by a mechanical stimulus involve paracrine intercellular communication, mediated by ATP release via connexin hemichannels, as well as gap junctional intercellular communication. Both mechanisms are inhibited by thrombin, which activates RhoA and hence results in myosin light chain phosphorylation. This study was conducted to examine the effects of adenosine, which is known to oppose thrombin-induced RhoA activation, thereby leading to myosin light chain dephosphorylation, on gap junctional intercellular communication and paracrine intercellular communication in cultured bovine corneal endothelial cells. An intercellular Ca(2+) wave was elicited by applying a mechanical stimulus to a single cell in a confluent monolayer. The area of Ca(2+) wave propagation was measured by [Ca(2+)](i) imaging using the fluorescent dye Fluo-4. Gap junctional intercellular communication was assessed by fluorescence recovery after photobleaching. Activity of hemichannels was determined by uptake of the hydrophilic dye Lucifer yellow in a Ca(2+)-free medium containing 2 mM EGTA. Adenosine triphosphate (ATP) release in response to mechanical stimulation was measured using the luciferin-luciferase technique. Gap26, a connexin mimetic peptide, was used to block hemichannels. Exposure to thrombin or TRAP-6 (a selective PAR-1 agonist) inhibited the Ca(2+) wave propagation by 70%. Pretreatment with adenosine prevented this inhibitory effect of thrombin. NECA (a potent A2B agonist) and forskolin, agents known to elevate cAMP in bovine corneal endothelial cells, also suppressed the effect of thrombin. The A1 receptor agonist CPA failed to inhibit the effect of thrombin. Similar to the effects on Ca(2+) wave propagation, adenosine prevented the thrombin-induced reduction in the fluorescence recovery during photobleaching experiments. Furthermore, pretreatment with adenosine prevented both thrombin and TRAP-6 from blocking the

  14. Clopidogrel inhibits angiogenesis of gastric ulcer healing via downregulation of vascular endothelial growth factor receptor 2.

    PubMed

    Luo, Jiing-Chyuan; Peng, Yen-Ling; Chen, Tseng-Shing; Huo, Teh-Ia; Hou, Ming-Chih; Huang, Hui-Chun; Lin, Han-Chieh; Lee, Fa-Yauh

    2016-09-01

    Although clopidogrel does not cause gastric mucosal injury, it does not prevent peptic ulcer recurrence in high-risk patients. We explored whether clopidogrel delays gastric ulcer healing via inhibiting angiogenesis and to elucidate the possible mechanisms. Gastric ulcers were induced in Sprague Dawley rats, and ulcer healing and angiogenesis of ulcer margin were compared between clopidogrel-treated rats and controls. The expressions of the proangiogenic growth factors and their receptors including basic fibroblast growth factor (bFGF), bFGF receptor (FGFR), vascular endothelial growth factor (VEGF), VEGFR1, VEGFR2, platelet-derived growth factor (PDGF)A, PDGFB, PDGFR A, PDGFR B, and phosphorylated form of mitogenic activated protein kinase pathways over the ulcer margin were compared via western blot and reverse transcription polymerase chain reaction. In vitro, human umbilical vein endothelial cells (HUVECs) were used to elucidate how clopidogrel inhibited growth factors-stimulated HUVEC proliferation. The ulcer sizes were significantly larger and the angiogenesis of ulcer margin was significantly diminished in the clopidogrel (2 and 10 mg/kg/d) treated groups. Ulcer induction markedly increased the expression of phosphorylated form of extracellular signal-regulated kinase (pERK), FGFR2, VEGF, VEGFR2, and PDGFRA when compared with those of normal mucosa. Clopidogrel treatment significantly decreased pERK, FGFR2, VEGF, VEGFR2, and PDGFRA expression at the ulcer margin when compared with those of the respective control group. In vitro, clopidogrel (10(-6)M) inhibited VEGF-stimulated (20 ng/mL) HUVEC proliferation, at least, via downregulation of VEGFR2 and pERK. Clopidogrel inhibits the angiogenesis of gastric ulcer healing at least partially by the inhibition of the VEGF-VEGFR2-ERK signal transduction pathway. Copyright © 2015. Published by Elsevier B.V.

  15. CLIC1 Inhibition Attenuates Vascular Inflammation, Oxidative Stress, and Endothelial Injury

    PubMed Central

    Hu, Xiao; Wang, Cui; Lu, Dezhao; Gong, Chenxue; Yang, Jinhuan; Zong, Lei

    2016-01-01

    Endothelial dysfunction, which includes endothelial oxidative damage and vascular inflammation, is a key initiating step in the pathogenesis of atherosclerosis (AS) and an independent risk factor for this disorder. Intracellular chloride channel 1 (CLIC1), a novel metamorphic protein, acts as a sensor of cell oxidation and is involved in inflammation. In this study, we hypothesize that CLIC1 plays an important role in AS. Apolipoprotein E-deficient mice were supplied with a normal diet or a high-fat and high-cholesterol diet for 8 weeks. Overexpressed CLIC1 was associated with the accelerated atherosclerotic plaque development, amplified oxidative stress, and in vivo release of inflammatory cytokines. We subsequently examined the underlying molecular mechanisms through in vitro experiments. Treatment of cultured human umbilical vein endothelial cells (HUVECs) with H2O2 induced endothelial oxidative damage and enhanced CLIC1 expression. Suppressing CLIC1 expression through gene knocked-out (CLIC1−/−) or using the specific inhibitor indanyloxyacetic acid-94 (IAA94) reduced ROS production, increased SOD enzyme activity, and significantly decreased MDA level. CLIC1−/− HUVECs exhibited significantly reduced expression of TNF-α and IL-1β as well as ICAM-1 and VCAM-1 at the protein levels. In addition, H2O2 promoted CLIC1 translocation to the cell membrane and insertion into lipid membranes, whereas IAA94 inhibited CLIC1 membrane translocation induced by H2O2. By contrast, the majority of CLIC1 did not aggregate on the cell membrane in normal HUVECs, and this finding is consistent with the changes in cytoplasmic chloride ion concentration. This study demonstrates for the first time that CLIC1 is overexpressed during AS development both in vitro and in vivo and can regulate the accumulation of inflammatory cytokines and production of oxidative stress. Our results also highlight that deregulation of endothelial functions may be associated with the membrane

  16. The coffee diterpene kahweol inhibits tumor necrosis factor-{alpha}-induced expression of cell adhesion molecules in human endothelial cells

    SciTech Connect

    Kim, Hyung Gyun; Kim, Ji Young; Hwang, Yong Pil; Lee, Kyung Jin; Lee, Kwang Youl; Kim, Dong Hee; Kim, Dong Hyun; Jeong, Hye Gwang . E-mail: hgjeong@chosun.ac.kr

    2006-12-15

    Endothelial cells produce adhesion molecules after being stimulated with various inflammatory cytokines. These adhesion molecules play an important role in the development of atherogenesis. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of kahweol, a coffee-specific diterpene. This study examined the effects of kahweol on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. Kahweol inhibited the adhesion of TNF{alpha}-induced monocytes to endothelial cells and suppressed the TNF{alpha}-induced protein and mRNA expression of the cell adhesion molecules, VCAM-1 and ICAM-1. Furthermore, kahweol inhibited the TNF{alpha}-induced JAK2-PI3K/Akt-NF-{kappa}B activation pathway in these cells. Overall, kahweol has anti-inflammatory and anti-atherosclerotic activities, which occurs partly by down-regulating the pathway that affects the expression and interaction of the cell adhesion molecules on endothelial cells.

  17. Downregulation of Fes inhibits VEGF-A-induced chemotaxis and capillary-like morphogenesis by cultured endothelial cells

    PubMed Central

    Kanda, Shigeru; Kanetake, Hiroshi; Miyata, Yasuyoshi

    2007-01-01

    Abstract The aim of this study was to determine whether the downregulation of endogenous Fes by siRNA in cultured endothelial cells affects vascular endothelial growth factor-A (VEGF-A)-induced chemotaxis and capillary-like morphogenesis, which are considered as angiogenic cellular responses in vitro. VEGF-A-treatment induced autophosphorylation of Fes in cultured endothelial cells.LY294002, a phosphoinositide 3-kinase inhibitor, significantly inhibited VEGF-A-induced chemotaxis and capillary-like morphogenesis.Downregulation of Fes attenuated these VEGF-A-induced cellular responses but LY294002 did not produce further inhibition of these responses. Downregulation of Fes neither affected VEGF-A-induced autophosphorylation of VEGF receptor 2 nor mitogen-activated protein kinase activation, but markedly decreased Akt activation.Taken together, our novel results indicate the involvement of Fes in VEGF-A-induced cellular responses by cultured endothelial cells. PMID:17521372

  18. Vitamin E analogues inhibit angiogenesis by selective induction of apoptosis in proliferating endothelial cells: the role of oxidative stress.

    PubMed

    Dong, Lan-Feng; Swettenham, Emma; Eliasson, Johanna; Wang, Xiu-Fang; Gold, Mikhal; Medunic, Yasmine; Stantic, Marina; Low, Pauline; Prochazka, Lubomir; Witting, Paul K; Turanek, Jaroslav; Akporiaye, Emmanuel T; Ralph, Stephen J; Neuzil, Jiri

    2007-12-15

    "Mitocans" from the vitamin E group of selective anticancer drugs, alpha-tocopheryl succinate (alpha-TOS) and its ether analogue alpha-TEA, triggered apoptosis in proliferating but not arrested endothelial cells. Angiogenic endothelial cells exposed to the vitamin E analogues, unlike their arrested counterparts, readily accumulated reactive oxygen species (ROS) by interfering with the mitochondrial redox chain and activating the intrinsic apoptotic pathway. The vitamin E analogues inhibited angiogenesis in vitro as assessed using the "wound-healing" and "tube-forming" models. Endothelial cells deficient in mitochondrial DNA (mtDNA) were resistant to the vitamin E analogues, both in ROS accumulation and apoptosis induction, maintaining their angiogenic potential. alpha-TOS inhibited angiogenesis in a mouse cancer model, as documented by ultrasound imaging. We conclude that vitamin E analogues selectively kill angiogenic endothelial cells, suppressing tumor growth, which has intriguing clinical implications.

  19. TRPV1 agonism inhibits endothelial cell inflammation via activation of eNOS/NO pathway.

    PubMed

    Wang, Youping; Cui, Lin; Xu, Hui; Liu, Suxiao; Zhu, Feiyun; Yan, Fengna; Shen, Si; Zhu, Mingjun

    2017-05-01

    Transient receptor potential vanilloid type 1 channel (TRPV1) is found to be expressed in endothelial cells (ECs) and activate endothelial nitric oxide synthase (eNOS). Recent studies implicate TRPV1 in attenuating inflammatory responses. However, the mechanisms underlying the beneficial effects remain unclear. In this study, we investigated whether TRPV1 suppresses inflammatory responses of ECs via eNOS/NO pathway. Human umbilical vein endothelial cells (HUVECs) and renal microvascular endothelial cells (MVECs) isolated from deoxycorticosterone (DOCA)-salt hypertensive mice were cultured in the presence of capsaicin (CAP, a specific TRPV1 agonist) with or without the specific inhibitor of TRPV1, NOS, or Ca(2+)-dependent phosphatidylinositol 3-kinase (PI3K)/Akt pathway, before lipopolysaccharide (LPS) stimulation. NO metabolites, protein expression, and inflammatory molecules were evaluated by Griess assay and immune assay-based multiplex analysis, respectively. Monocyte adhesion was determined by measuring the fluorescently labeled human monocytes attached to LPS-stimulated ECs. In HUVECs, treatment with CAP increased NO production, and CAP-induced NO production was accompanied by increased eNOS(ser1177) phosphorylation. Additionally, CAP attenuated LPS-induced cytokine and chemokine production, adhesion molecule expression, activation of NF-κB, and monocyte adhesion in HUVECs, and these effects were abrogated by the inhibition of TRPV1, NOS, or Ca(2+)-dependent PI3K/Akt pathway. Moreover, these protective actions of TRPV1 were also observed in renal MVECs isolated from DOCA-salt hypertensive mice. Our results indicate that TRPV1 activation suppresses the inflammatory response of ECs via the activation of Ca(2+)/PI3K/Akt/eNOS/NO pathway, the protective effects are also documented in ECs derived from salt-sensitive hypertensive mice. Copyright © 2017. Published by Elsevier B.V.

  20. Salvianolic acid B inhibits platelets-mediated inflammatory response in vascular endothelial cells.

    PubMed

    Xu, Shixin; Zhong, Aiqin; Bu, Xiaokun; Ma, Huining; Li, Wei; Xu, Xiaomin; Zhang, Junping

    2015-01-01

    Salvianolic acid B (SAB) is a hydrophilic component isolated from the Chinese herb Salviae miltiorrhizae, which has been used clinically for the treatment of ischemic cardiovascular and cerebrovascular diseases. Platelets-mediated vascular inflammatory response contributes to the initiation and progression of atherosclerosis. In this paper, we focus on the modulating effects of SAB on the inflammatory reaction of endothelial cells triggered by activated platelets. Human umbilical vein endothelial cells (EA.hy926) were pretreated with SAB followed by co-culture with ADP-activated platelets. Adhesion of platelets to endothelial cells was observed by amorphological method. The activation of nuclear factor-kappa B was evaluated by NF-κB p65 nuclear translocation and the protein phosphorylation. A determination of the pro-inflammatory mediators (ICAM-1, IL-1β, IL-6, IL-8, MCP-1) mRNA and protein were also conducted. In addition, the inhibitory effects of SAB on platelets activation were also evaluated using a platelet aggregation assay and assessing the release level of soluble P-selectin. The results showed that SAB dose-dependently inhibited ADP- or α-thrombin-induced human platelets aggregation in platelet rich plasma (PRP) samples, and significantly decreased soluble P-selectin release from both agonists stimulated washed platelets. It was also found that pre-treatment with SAB reduced adhesion of ADP-activated platelets to EA.hy926 cells and inhibited NF-κB activation. In addition, SAB significantly suppressed pro-inflammatory mediators mRNA and protein in EA.hy926 cells in a dose-dependent manner. These results indicated that, in addition to its inhibitory effects on platelets activation, SAB was able to attenuate platelets-mediated inflammatory responses in endothelial cells even if the platelets had already been activated. This anti-inflammatory effect was related to the inhibition of NF-κB activation. Our findings suggest that SAB may be a potential

  1. Phentolamine inhibits angiogenesis in vitro: Suppression of proliferation migration and differentiation of human endothelial cells.

    PubMed

    Pan, Liangli; Liu, Chenyang; Kong, Yanan; Piao, Zhengguo; Cheng, Biao

    2016-06-16

    It is widely known that the β-adrenergic receptor (AR) blocker (propranolol) inhibits human endothelial cell (EC) angiogenesis in vitro, but how the α-AR antagonist (phentolamine) affects human EC angiogenesis has not yet been studied. Here, we show for the first time that both human dermal microvascular ECs (HDMECs) and human brain microvascular ECs (HBMECs) express α-ARs. Moreover, our results indicate that phentolamine inhibits the proliferation, migration, and tubulogenesis of HDMECs and HBMECs. Finally, VEGFR-2 and Ang1/2 expression of HDMECs was suppressed by phentolamine. Together, these results indicate that phentolamine impairs several critical events of neovascularization, and α-ARs, as well as the VEGF/VEGFR-2 and Ang/Tie-2 signaling pathways, may be involved in these processes. Our results suggest a novel therapeutic strategy for the use of α-blockers in the treatment of human angiogenesis-dependent diseases.

  2. Deoxynivalenol inhibits proliferation and induces apoptosis in human umbilical vein endothelial cells.

    PubMed

    Deng, Chao; Ji, Changyun; Qin, Weisen; Cao, Xifeng; Zhong, Jialian; Li, Yugu; Srinivas, Swaminath; Feng, Youjun; Deng, Xianbo

    2016-04-01

    Deoxynivalenol (DON) is a stable mycotoxins found in cereals infected by certain fungal species and causes adverse health effects in animals and human such as vomiting, diarrhea and reproductive toxicity. In this study, we investigated the toxic and apoptotic effects of DON in human umbilical vein endothelial cells (HUVECs), a good model for studying inflammation. The results show that DON significantly inhibited the viability of HUVECs. DON could also inhibit the proliferation of HUVECs through G2/M phase arrest in cell cycle progression. Moreover, oxidative stress induced by DON was indicated by observations of increased levels of reactive oxygen species (ROS). In addition, DON also causes mitochondrial damage by decreasing the mitochondrial membrane potential and inducing apoptosis by up-regulation of apoptosis-related genes like caspase-3, caspase-9, and Bax genes, and down-regulation of Bcl-2 gene. These results together suggest that DON could induce cell cycle arrest, oxidative stress, and apoptosis in HUVECs.

  3. Activation of Protein Kinase G (PKG) Reduces Neointimal Hyperplasia, Inhibits Platelet Aggregation, and Facilitates Re-endothelialization

    PubMed Central

    Kim, Ju-Young; Yang, Han-Mo; Lee, Joo-Eun; Kim, Baek-Kyung; Jin, Sooryeonhwa; Lee, Jaewon; Park, Kyung-Woo; Cho, Hyun-Jai; Kwon, Yoo-Wook; Lee, Hae-Young; Kang, Hyun-Jae; Oh, Byung-Hee; Park, Young-Bae; Kim, Hyo-Soo

    2016-01-01

    In spite of its great success in reducing restenosis, drug-eluting stent (DES) has unfavorable aspects such as stent thrombosis and delayed re-endothelialization. We examined the effects of PKG activation by Exisulind on neointimal formation, platelet aggregation, and re-endothelialization. Exisulind significantly reduced VSMCs viability, cell cycle progression, migration, and neointimal hyperplasia after vascular injury in rat carotid arteries. Interestingly, in contrast to the effect on VSMC viability, Exisulind did not reduce the viability of endothelial cells. Increased PKG activity by Exisulind inhibited PDGF-stimulated phenotype change of VSMCs from a contractile to a synthetic form. Conversely, the use of PKG inhibitor or gene transfer of dominant-negative PKG reversed the effects of Exisulind, resulting in the increased viability of VSMCs and neointimal formation. In addition, Exisulind facilitated the differentiation of peripheral blood mononuclear cells to endothelial lineage via PKG pathway, while inhibiting to VSMCs lineage, which was correlated with the enhanced re-endothelialization in vivo. Finally, Exisulind reduced platelet aggregation, which was mediated via PKG activation. This study demonstrated that Exisulind inhibits neointimal formation and platelet aggregation while increasing re-endothelialization via PKG pathway. These findings suggest that Exisulind could be a promising candidate drug of DES for the prevention of restenosis without other complications. PMID:27833146

  4. Fucoidan extract derived from Undaria pinnatifida inhibits angiogenesis by human umbilical vein endothelial cells.

    PubMed

    Liu, Fang; Wang, Jia; Chang, Alan K; Liu, Bing; Yang, Lili; Li, Qiaomei; Wang, Peisheng; Zou, Xiangyang

    2012-06-15

    In recent years, anti-angiogenic therapy has become an effective strategy for inhibiting tumor growth. Fucoidan is a class of fucose-enriched sulfated polysaccharides found in brown algae, and it is known to have strong anti-tumor property. Using a human umbilical vein endothelial cells (HUVEC)-based cell culture model, the present study investigated the anti-angiogenic activity of fucoidan extracted from the brown seaweed Undaria pinnatifida. Treatment of HUVECs with various concentrations of fucoidan resulted in significant inhibition of cell proliferation, cell migration, tube formation and vascular network formation. However, significant inhibition of cell proliferation only occurred with longer treatment time (48 h instead of 24h or less). About 40% of cell proliferation and cell migration and 61% of tube formation by HUVECs were inhibited by 400 μg/ml fucoidan, the maximum concentration tested. These results appeared to suggest that modulation of angiogenesis by fucoidan might not occur through growth inhibition and apoptosis. Ex vivo angiogenesis assay demonstrated that at 100 μg/ml, fucoidan caused significant reduction in microvessel outgrowth. Western blot and RT-PCR analyses indicated that at 400 μg/ml, fucoidan significantly reduced the expression of the angiogenesis factor VEGF-A in the suppression of angiogenesis activity. Our results showed that fucoidan isolated from U. pinnatifida may have a new therapeutic potential in the prevention angiogenesis-related diseases.

  5. Endothelial-specific inhibition of NF-κB enhances functional haematopoiesis

    PubMed Central

    Poulos, Michael G.; Ramalingam, Pradeep; Gutkin, Michael C.; Kleppe, Maria; Ginsberg, Michael; Crowley, Michael J. P.; Elemento, Olivier; Levine, Ross L.; Rafii, Shahin; Kitajewski, Jan; Greenblatt, Matthew B.; Shim, Jae-Hyuck; Butler, Jason M.

    2016-01-01

    Haematopoietic stem cells (HSCs) reside in distinct niches within the bone marrow (BM) microenvironment, comprised of endothelial cells (ECs) and tightly associated perivascular constituents that regulate haematopoiesis through the expression of paracrine factors. Here we report that the canonical NF-κB pathway in the BM vascular niche is a critical signalling axis that regulates HSC function at steady state and following myelosuppressive insult, in which inhibition of EC NF-κB promotes improved HSC function and pan-haematopoietic recovery. Mice expressing an endothelial-specific dominant negative IκBα cassette under the Tie2 promoter display a marked increase in HSC activity and self-renewal, while promoting the accelerated recovery of haematopoiesis following myelosuppression, in part through protection of the BM microenvironment following radiation and chemotherapeutic-induced insult. Moreover, transplantation of NF-κB-inhibited BM ECs enhanced haematopoietic recovery and protected mice from pancytopenia-induced death. These findings pave the way for development of niche-specific cellular approaches for the treatment of haematological disorders requiring myelosuppressive regimens. PMID:28000664

  6. Olive oil compounds inhibit vascular endothelial growth factor receptor-2 phosphorylation.

    PubMed

    Lamy, Sylvie; Ouanouki, Amira; Béliveau, Richard; Desrosiers, Richard R

    2014-03-10

    Vascular endothelial growth factor (VEGF) triggers crucial signaling processes that regulate tumor angiogenesis and, therefore, represents an attractive target for the development of novel anticancer therapeutics. Several epidemiological studies have confirmed that abundant consumption of foods from plant origin is associated with reduced risk of developing cancers. In the Mediterranean basin, the consumption of extra virgin olive oil is an important constituent of the diet. Compared to other vegetable oils, the presence of several phenolic antioxidants in olive oil is believed to prevent the occurrence of a variety of pathological processes, such as cancer. While the strong antioxidant potential of these molecules is well characterized, their antiangiogenic activities remain unknown. The aim of this study is to investigate whether tyrosol (Tyr), hydroxytyrosol (HT), taxifolin (Tax), oleuropein (OL) and oleic acid (OA), five compounds contained in extra virgin olive oil, can affect in vitro angiogenesis. We found that HT, Tax and OA were the most potent angiogenesis inhibitors through their inhibitory effect on specific autophosphorylation sites of VEGFR-2 (Tyr951, Tyr1059, Tyr1175 and Tyr1214) leading to the inhibition of endothelial cell (EC) signaling. Inhibition of VEGFR-2 by these olive oil compounds significantly reduced VEGF-induced EC proliferation and migration as well as their morphogenic differentiation into capillary-like tubular structures in Matrigel. Our study demonstrates that HT, Tax and OA are novel and potent inhibitors of the VEGFR-2 signaling pathway. These findings emphasize the chemopreventive properties of olive oil and highlight the importance of nutrition in cancer prevention.

  7. SIRT1 inhibits inflammatory response partly through regulation of NLRP3 inflammasome in vascular endothelial cells.

    PubMed

    Li, Yanxiang; Wang, Ping; Yang, Xiaofeng; Wang, Weirong; Zhang, Jiye; He, Yanhao; Zhang, Wei; Jing, Ting; Wang, Bo; Lin, Rong

    2016-09-01

    Emerging evidence has indicated that vascular endothelial cells (ECs) not only form the barrier between blood and the vessel wall but also serve as conditional innate immune cells. Our previous study found that SIRT1, a class III histone deacetylase, inhibits the inflammatory response in ECs. Recent studies revealed that SIRT1 also participates in the modulation of immune responses. Although the NLRP3 inflammasome is known to be a crucial component of the innate immune system, there is no direct evidence demonstrating the anti-inflammatory effect of SIRT1 on ECs through the NLRP3 inflammasome. In this study, we observed that lipopolysaccharide (LPS) and adenosine triphosphate (ATP) triggered the activation of NLRP3 inflammasome in human umbilical vein ECs (HUVECs). Moreover, SIRT1 expression was reduced in HUVECs stimulated with LPS and ATP. SIRT1 activator inhibited the expression of monocyte chemotactic protein-1 (MCP-1) and C-reactive protein (CRP), whereas SIRT1 knockdown resulted in significant increases in MCP-1 and CRP levels in HUVECs stimulated with LPS and ATP. Importantly, the lack of SIRT1 enhanced NLRP3 inflammasome activation and subsequent caspase-1 cleavage. On the other hand, NLRP3 siRNA blocked the activation of the NLRP3 inflammasome in HUVECs stimulated with LPS plus ATP. Further study revealed that NLRP3 inflammasome blockade significantly reduced MCP-1 and CRP production in HUVECs. In vivo studies indicated that implantation of the periarterial carotid collar inhibited arterial SIRT1 expression in rabbits. Meanwhile, treatment with a SIRT1 activator decreased the expression levels of MCP-1 and CRP in collared arteries and the interleukin (IL)-1β level in serum. Taken together, these findings indicate that NLRP3 inflammasome activation promoted endothelial inflammation and that SIRT1 inhibits the inflammatory response partly through regulation of the NLRP3 inflammasome in ECs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Cocaine Inhibits Store-Operated Ca2+ Entry in Brain Microvascular Endothelial Cells: Critical Role for Sigma-1 Receptors

    PubMed Central

    Brailoiu, G. Cristina; Deliu, Elena; Console-Bram, Linda M; Soboloff, Jonathan; Abood, Mary E; Unterwald, Ellen M; Brailoiu, Eugen

    2015-01-01

    Sigma-1 receptor (Sig-1R) is an intracellular chaperone protein with many ligands, located at the endoplasmic reticulum. Binding of cocaine to Sig-1R has previously been found to modulate endothelial functions. In the present study, we show that cocaine dramatically inhibits store-operated Ca2+ entry (SOCE), a Ca2+ influx mechanism promoted by depletion of intracellular Ca2+ stores, in rat brain microvascular endothelial cells. Using either Sig-1R shRNA or pharmacological inhibition with the unrelated Sig-1R antagonists BD-1063 and NE-100, we show that cocaine-induced SOCE inhibition is dependent on Sig-1R. In addition to revealing new insight into fundamental mechanisms of cocaine-induced changes in endothelial function, these studies provide an unprecedented role for Sig-1R as a SOCE inhibitor. PMID:26467159

  9. Cocaine inhibits store-operated Ca2+ entry in brain microvascular endothelial cells: critical role for sigma-1 receptors.

    PubMed

    Brailoiu, G Cristina; Deliu, Elena; Console-Bram, Linda M; Soboloff, Jonathan; Abood, Mary E; Unterwald, Ellen M; Brailoiu, Eugen

    2016-01-01

    Sigma-1 receptor (Sig-1R) is an intracellular chaperone protein with many ligands, located at the endoplasmic reticulum (ER). Binding of cocaine to Sig-1R has previously been found to modulate endothelial functions. In the present study, we show that cocaine dramatically inhibits store-operated Ca(2+) entry (SOCE), a Ca(2+) influx mechanism promoted by depletion of intracellular Ca(2+) stores, in rat brain microvascular endothelial cells (RBMVEC). Using either Sig-1R shRNA or pharmacological inhibition with the unrelated Sig-1R antagonists BD-1063 and NE-100, we show that cocaine-induced SOCE inhibition is dependent on Sig-1R. In addition to revealing new insight into fundamental mechanisms of cocaine-induced changes in endothelial function, these studies indicate an unprecedented role for Sig-1R as a SOCE inhibitor.

  10. Geraniol improves endothelial function by inhibiting NOX-2 derived oxidative stress in high fat diet fed mice

    SciTech Connect

    Wang, Xiaoyu; Zhao, Shiqi; Su, Mengqi; Sun, Li; Zhang, Song; Wang, Dingyu; Liu, Zhaorui; Yuan, Yue; Liu, Yang; Li, Yue

    2016-05-20

    Endothelial dysfunction occurs in obese patients and high-fat diet (HFD) fed experimental animals. While geraniol has been reported to ameliorate inflammation and oxidative stress, inhibit tumor cell proliferation, and improve atherosclerosis, its direct effect on endothelial function remains uncharacterized. The present study therefore investigated the effect of geraniol on endothelial function in HFD mice and its underlying mechanisms. C57 BL/6 mice were fed an HFD (n = 40) or a normal diet (n = 20) for 8 weeks. HFD fed mice then were randomized to intraperitoneal treatment with geraniol (n = 20) or vehicle (n = 20) for another 6 weeks. Acetylcholine (Ach)-induced endothelial dependent vasorelaxation was measured on wire myography; reactive oxygen species (ROS) generation was assessed by fluorescence imaging, and NADPH oxidases (NOXs) and adhesive molecules VCAM-1 and ICAM-1 protein expression by western blotting. Geraniol improved endothelial function in HFD fed mice, as evidenced by its: 1. restoring endothelial dependent vasorelaxation induced by Ach, and reversing increased VCAM-1 and ICAM-1 expression; 2. attenuating HFD induced increased serum TBARS and aortic ROS generation; and 3. downregulating aortic NOX-2 expression in both HFD fed mice and in palmitic acid treated endothelial cells. Geraniol therefore protects against endothelial dysfunction induced by HFD through reducing NOX-2 associated ROS generation. -- Highlights: •Geraniol improved endothelial dependent relaxation in high fat diet fed mice. •Geraniol alleviated vascular injury in high fat diet fed mice. •Geraniol inhibited ROS generation through downregulating NOX-2 expression.

  11. Infantile hemangioma-derived stem cells and endothelial cells are inhibited by class 3 semaphorins

    SciTech Connect

    Nakayama, Hironao; Huang, Lan; Kelly, Ryan P.; Oudenaarden, Clara R.L.; Dagher, Adelle; Hofmann, Nicole A.; Moses, Marsha A.; Bischoff, Joyce; Klagsbrun, Michael

    2015-08-14

    Class 3 semaphorins were discovered as a family of axon guidance molecules, but are now known to be involved in diverse biologic processes. In this study, we investigated the anti-angiogenic potential of SEMA3E and SEMA3F (SEMA3E&F) in infantile hemangioma (IH). IH is a common vascular tumor that involves both vasculogenesis and angiogenesis. Our lab has identified and isolated hemangioma stem cells (HemSC), glucose transporter 1 positive (GLUT1{sup +}) endothelial cells (designated as GLUT1{sup sel} cells) based on anti-GLUT1 magnetic beads selection and GLUT1-negative endothelial cells (named HemEC). We have shown that these types of cells play important roles in hemangiogenesis. We report here that SEMA3E inhibited HemEC migration and proliferation while SEMA3F was able to suppress the migration and proliferation in all three types of cells. Confocal microscopy showed that stress fibers in HemEC were reduced by SEMA3E&F and that stress fibers in HemSC were decreased by SEMA3F, which led to cytoskeletal collapse and loss of cell motility in both cell types. Additionally, SEMA3E&F were able to inhibit vascular endothelial growth factor (VEGF)-induced sprouts in all three types of cells. Further, SEMA3E&F reduced the level of p-VEGFR2 and its downstream p-ERK in HemEC. These results demonstrate that SEMA3E&F inhibit IH cell proliferation and suppress the angiogenic activities of migration and sprout formation. SEMA3E&F may have therapeutic potential to treat or prevent growth of highly proliferative IH. - Highlights: • SEMA3E&F reduce actin stress fibers and induce cytoskeletal collapse in HemEC. • SEMA3E&F inhibit angiogenic activities of HemEC. • SEMA3E&F can interrupt the VEGF-A-VEGFR2-ERK signaling pathway in HemEC. • Plexin D1 and NRP2 are induced during HemSC/GLUT1{sup sel}-to-EC differentiation.

  12. Effects of Vascular-Endothelial Protein Tyrosine Phosphatase Inhibition on Breast Cancer Vasculature and Metastatic Progression

    PubMed Central

    2013-01-01

    Background The solid tumor microvasculature is characterized by structural and functional abnormality and mediates several deleterious aspects of tumor behavior. Here we determine the role of vascular endothelial protein tyrosine phosphatase (VE-PTP), which deactivates endothelial cell (EC) Tie-2 receptor tyrosine kinase, thereby impairing maturation of tumor vessels. Methods AKB-9778 is a first-in-class VE-PTP inhibitor. We examined its effects on ECs in vitro and on embryonic angiogenesis in vivo using zebrafish assays. We studied the impact of AKB-9778 therapy on the tumor vasculature, tumor growth, and metastatic progression using orthotopic models of murine mammary carcinoma as well as spontaneous and experimental metastasis models. Finally, we used endothelial nitric oxide synthase (eNOS)–deficient mice to establish the role of eNOS in mediating the effects of VE-PTP inhibition. All statistical tests were two-sided. Results AKB-9778 induced ligand-independent Tie-2 activation in ECs and impaired embryonic zebrafish angiogenesis. AKB-9778 delayed the early phase of mammary tumor growth by maintaining vascular maturity (P < .01, t test); slowed growth of micrometastases (P < .01, χ2 test) by preventing extravasation of tumor cells (P < 0.01, Fisher exact test), resulting in a trend toward prolonged survival (27.0 vs 36.5 days; hazard ratio of death = 0.33, 95% confidence interval = 0.11 to 1.03; P = .05, Mantel–Cox test); and stabilized established primary tumor blood vessels, enhancing tumor perfusion (P = .03 for 4T1 tumor model and 0.05 for E0771 tumor model, by two-sided t tests) and, hence, radiation response (P < .01, analysis of variance; n = 7 mice per group). The effects of AKB-9778 on tumor vessels were mediated in part by endothelial nitric oxide synthase activation. Conclusions Our results demonstrate that pharmacological VE-PTP inhibition can normalize the structure and function of tumor vessels through Tie-2 activation, which delays tumor

  13. Lithium prevents early cytosolic calcium increase and secondary injurious calcium overload in glycolytically inhibited endothelial cells

    SciTech Connect

    Bosche, Bert; Schäfer, Matthias; Graf, Rudolf; Härtel, Frauke V.; Schäfer, Ute; Noll, Thomas

    2013-05-03

    Highlights: •We investigate free calcium as a central signalling element in endothelial cells. •Inhibition of glycolysis with 2-deoxy-D-glucose reduces cellular ATP. •This manoeuvre leads to a biphasic increase and overload of free calcium. •Pre-treatment with lithium for 24 h abolishes both phases of the calcium increase. •This provides a new strategy to protect endothelial calcium homeostasis and barrier function. -- Abstract: Cytosolic free calcium concentration ([Ca{sup 2+}]{sub i}) is a central signalling element for the maintenance of endothelial barrier function. Under physiological conditions, it is controlled within narrow limits. Metabolic inhibition during ischemia/reperfusion, however, induces [Ca{sup 2+}]{sub i} overload, which results in barrier failure. In a model of cultured porcine aortic endothelial monolayers (EC), we addressed the question of whether [Ca{sup 2+}]{sub i} overload can be prevented by lithium treatment. [Ca{sup 2+}]{sub i} and ATP were analysed using Fura-2 and HPLC, respectively. The combined inhibition of glycolytic and mitochondrial ATP synthesis by 2-desoxy-D-glucose (5 mM; 2-DG) plus sodium cyanide (5 mM; NaCN) caused a significant decrease in cellular ATP content (14 ± 1 nmol/mg protein vs. 18 ± 1 nmol/mg protein in the control, n = 6 culture dishes, P < 0.05), an increase in [Ca{sup 2+}]{sub i} (278 ± 24 nM vs. 71 ± 2 nM in the control, n = 60 cells, P < 0.05), and the formation of gaps between adjacent EC. These observations indicate that there is impaired barrier function at an early state of metabolic inhibition. Glycolytic inhibition alone by 10 mM 2-DG led to a similar decrease in ATP content (14 ± 2 nmol/mg vs. 18 ± 1 nmol/mg in the control, P < 0.05) with a delay of 5 min. The [Ca{sup 2+}]{sub i} response of EC was biphasic with a peak after 1 min (183 ± 6 nM vs. 71 ± 1 nM, n = 60 cells, P < 0.05) followed by a sustained increase in [Ca{sup 2+}]{sub i}. A 24-h pre-treatment with 10 mM of lithium

  14. Hydrogen sulfide inhibits endothelial nitric oxide formation and receptor ligand-mediated Ca(2+) release in endothelial and smooth muscle cells.

    PubMed

    Kloesch, Burkhard; Steiner, Guenter; Mayer, Bernd; Schmidt, Kurt

    2016-02-01

    In the vascular system, ATP-sensitive K(+)-channels are a target for H2S. Recent evidence suggests that H2S may also modulate Na(+)- and Ca(2+)-permeable channels and intracellular Ca(2+) stores, but the influence of H2S on endothelial Ca(2+) dynamics and Ca(2+)-dependent activation of endothelial nitric oxide synthase (eNOS) is unclear. In this study, we investigated the effects of H2S on Ca(2+) signaling in endothelial and smooth muscle cells with special emphasis given to the role of H2S in modulating endothelial NO formation. Experiments were performed with endothelial cells from porcine aorta, the human endothelial cell line HMEC-1, and smooth muscle cells from rat aorta and trachea. Mobilization of intracellular Ca(2+) and Ca(2+) entry was monitored with Fura-2. Activity of eNOS was determined as conversion of incorporated l-[(3)H]arginine into l-[(3)H]citrulline. Incubation of endothelial cells with the H2S donors sodium hydrogen sulfide (NaHS) and GYY4137 blocked activation of eNOS by the receptor agonist ATP but not by the Ca(2+) ionophore A23187. Data revealed that H2S inhibited ATP-induced release of Ca(2+) from intracellular stores indicating that H2S attenuates eNOS activity by blocking capacitative Ca(2+) entry. A similar inhibitory effect of H2S on ATP-induced Ca(2+) release and Ca(2+) entry was also observed in human microvascular endothelial cells and smooth muscle cells. H2S antagonized Ca(2+) mobilization by receptor agonists and store-operated Ca(2+) entry thereby limiting eNOS activation and NO formation. The effect of H2S on Ca(2+) stores was not restricted to endothelial cells but was also observed in vascular and tracheal smooth muscle cells. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  15. A Furan-Based Lewis-Y-(CD174)-Saccharide Mimetic Inhibits Endothelial Functions and In Vitro Angiogenesis.

    PubMed

    Sauer, Sandra; Meissner, Tobias; Moehler, Thomas

    2015-01-01

    Angiogenesis is a fundamental process underlying cancer progression and autoimmune disease. Lewis Y is known as a regulated glycan-structure supporting human endothelial function and angiogenesis. We hypothesize that Lewis Y based analogues interfere with Lewis Y mediated endothelial functions and angiogenesis. We therefore evaluated the ability of 3, 4-bis [(b-D-galactopyranosyl)osy]-methyl-furan (BGF) a furan-based Lewis-Y saccharide mimetic to inhibit human endothelial adhesion, migration and in vitro angiogenesis. The ability of BGF and additional furan-based saccharide-mimetics was investigated to inhibit adhesion and migration of human bone marrow endothelial cells (HBMEC). Influence of BGF was tested on a multicelluar in vitro - angiogenesis assay in the presence of VEGF. BGF significantly inhibited HBMEC adhesion and migration stimulated by TNF-alpha by up to 70%. The anti-adhesive effect of BGF was particularly evident when HBMEC adhesion and migration was tested on collagen as extracellular matrix with weaker effect when laminin and fibronectin were used as an extracellular matrix. BGF was ineffective when HBMEC were stimulated with VEGF. The inhibition of endothelial function translated into a significant inhibitory effect of BGF in the multicellular in vitro angiogenesis-assay. BGF reduced the angiogenesis index compared to the positive controls by 32%. We identified the ability of the furan-based Lewis Y saccharide mimetic BGF as a specific modulator of TNF-alpha activated endothelial function and in vitro angiogenesis. BGF and other related glycan analogues should further be explored for their ability to down modulate endothelial activation in TNF-alpha driven pathophysiologic conditions in autoimmune disease and cancer indications.

  16. Grateloupia longifolia polysaccharide inhibits angiogenesis by downregulating tissue factor expression in HMEC-1 endothelial cells

    PubMed Central

    Zhang, Chao; Yang, Fan; Zhang, Xiong-Wen; Wang, Shun-Chun; Li, Mei-Hong; Lin, Li-Ping; Ding, Jian

    2006-01-01

    The antiangiogenic and antitumor properties of Grateloupia longifolia polysaccharide (GLP), a new type of polysaccharide isolated from the marine alga, were investigated with several in vitro and in vivo models. Possible mechanisms underlying its antiangiogenic activity were also assessed. GLP dose-dependently inhibited proliferation of human microvascular endothelial cells (HMEC-1) and human umbilical vein endothelial cells (HUVEC), with IC50 values of 0.86 and 0.64 mg ml−1, respectively. In tube formation and cell migration assays using HMEC-1 cells, noncytotoxic doses of GLP significantly inhibited formation of intact tube networks and reduced the number of migratory cells. Inhibition by GLP was VEGF-independent. In the chick chorioallantoic membrane (CAM) assay, GLP (2.5 μg egg−1) reduced new vessel formation compared with the vehicle control. GLP (0.1 mg plug−1) also reduced the vessel density in Matrigel plugs implanted in mice. The levels of pan and phosphorylated recptors for VEGF, VEGFR-1 (flt-1) and VEGFR-2 (KDR) were not significantly altered by 5 mg ml−1 GLP treatment of HMEC-1, although tissue factor (TF) showed significant decreases at both mRNA and protein levels following GLP treatment. In mice bearing sarcoma-180 cells, intravenous administration of GLP (200 mg kg−1) decreased tumor weight by 52% without obvious toxicity. Vascular density in sections of the tumor was reduced by 64% after GLP treatment. Collectively, these results indicate that GLP has antitumor properties, associated at least, in part, with the antiangiogenesis induced by downregulation of TF. PMID:16715123

  17. Grateloupia longifolia polysaccharide inhibits angiogenesis by downregulating tissue factor expression in HMEC-1 endothelial cells.

    PubMed

    Zhang, Chao; Yang, Fan; Zhang, Xiong-Wen; Wang, Shun-Chun; Li, Mei-Hong; Lin, Li-Ping; Ding, Jian

    2006-07-01

    1. The antiangiogenic and antitumor properties of Grateloupia longifolia polysaccharide (GLP), a new type of polysaccharide isolated from the marine alga, were investigated with several in vitro and in vivo models. Possible mechanisms underlying its antiangiogenic activity were also assessed. 2. GLP dose-dependently inhibited proliferation of human microvascular endothelial cells (HMEC-1) and human umbilical vein endothelial cells (HUVEC), with IC50 values of 0.86 and 0.64 mg ml(-1), respectively. In tube formation and cell migration assays using HMEC-1 cells, noncytotoxic doses of GLP significantly inhibited formation of intact tube networks and reduced the number of migratory cells. Inhibition by GLP was VEGF-independent. 3. In the chick chorioallantoic membrane (CAM) assay, GLP (2.5 microg egg(-1)) reduced new vessel formation compared with the vehicle control. GLP (0.1 mg plug(-1)) also reduced the vessel density in Matrigel plugs implanted in mice. 4. The levels of pan and phosphorylated receptors for VEGF, VEGFR-1 (flt-1) and VEGFR-2 (KDR) were not significantly altered by 5 mg ml(-1) GLP treatment of HMEC-1, although tissue factor (TF) showed significant decreases at both mRNA and protein levels following GLP treatment. 5. In mice bearing sarcoma-180 cells, intravenous administration of GLP (200 mg kg(-1)) decreased tumor weight by 52% without obvious toxicity. Vascular density in sections of the tumor was reduced by 64% after GLP treatment. 6. Collectively, these results indicate that GLP has antitumor properties, associated at least, in part, with the antiangiogenesis induced by downregulation of TF.

  18. Advanced Glycation End Products Inhibit the Proliferation of Human Umbilical Vein Endothelial Cells by Inhibiting Cathepsin D

    PubMed Central

    Li, Yuan; Chang, Ye; Ye, Ning; Dai, Dongxue; Chen, Yintao; Zhang, Naijin; Sun, Guozhe; Sun, Yingxian

    2017-01-01

    We aimed to investigate the effect of advanced glycation end products (AGEs) on the proliferation and migration ability of human umbilical vein endothelial cells (HUVECs). Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay, real-time cell analyzer and 5-Ethynyl-2′-deoxyuridine (EdU) staining. Cell migration was detected by wound-healing and transwell assay. AGEs significantly inhibited the proliferation and migration of HUVECs in a time-and dose-dependent way. Western blotting revealed that AGEs dramatically increased the expression of microtubule-associated protein 1 light chain 3 (LC3) II/I and p62. Immunofluorescence of p62 and acridine orange staining revealed that AGEs significantly increased the expression of p62 and the accumulation of autophagic vacuoles, respectively. Chloroquine (CQ) could further promote the expression of LC3 II/I and p62, increase the accumulation of autophagic vacuoles and promote cell injury induced by AGEs. In addition, AGEs reduced cathepsin D (CTSD) expression in a time-dependent way. Overexpression of wild-type CTSD significantly decreased the ratio of LC 3 II/I as well as p62 accumulation induced by AGEs, but overexpression of catalytically inactive mutant CTSD had no such effects. Only overexpression of wild-type CTSD could restore the proliferation of HUVECs inhibited by AGEs. However, overexpression of both wild-type CTSD and catalytically inactive mutant CTSD could promote the migration of HUVECs inhibited by AGEs. Collectively, our study found that AGEs inhibited the proliferation and migration in HUVECs and promoted autophagic flux, which in turn played a protective role against AGEs-induced cell injury. CTSD, in need of its catalytic activity, may promote proliferation in AGEs-treated HUVECs independent of the autophagy-lysosome pathway. Meanwhile, CTSD could improve the migration of AGEs-treated HUVECs regardless of its enzymatic activity. PMID:28218663

  19. Advanced Glycation End Products Inhibit the Proliferation of Human Umbilical Vein Endothelial Cells by Inhibiting Cathepsin D.

    PubMed

    Li, Yuan; Chang, Ye; Ye, Ning; Dai, Dongxue; Chen, Yintao; Zhang, Naijin; Sun, Guozhe; Sun, Yingxian

    2017-02-17

    We aimed to investigate the effect of advanced glycation end products (AGEs) on the proliferation and migration ability of human umbilical vein endothelial cells (HUVECs). Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay, real-time cell analyzer and 5-Ethynyl-2'-deoxyuridine (EdU) staining. Cell migration was detected by wound-healing and transwell assay. AGEs significantly inhibited the proliferation and migration of HUVECs in a time-and dose-dependent way. Western blotting revealed that AGEs dramatically increased the expression of microtubule-associated protein 1 light chain 3 (LC3) II/I and p62. Immunofluorescence of p62 and acridine orange staining revealed that AGEs significantly increased the expression of p62 and the accumulation of autophagic vacuoles, respectively. Chloroquine (CQ) could further promote the expression of LC3 II/I and p62, increase the accumulation of autophagic vacuoles and promote cell injury induced by AGEs. In addition, AGEs reduced cathepsin D (CTSD) expression in a time-dependent way. Overexpression of wild-type CTSD significantly decreased the ratio of LC 3 II/I as well as p62 accumulation induced by AGEs, but overexpression of catalytically inactive mutant CTSD had no such effects. Only overexpression of wild-type CTSD could restore the proliferation of HUVECs inhibited by AGEs. However, overexpression of both wild-type CTSD and catalytically inactive mutant CTSD could promote the migration of HUVECs inhibited by AGEs. Collectively, our study found that AGEs inhibited the proliferation and migration in HUVECs and promoted autophagic flux, which in turn played a protective role against AGEs-induced cell injury. CTSD, in need of its catalytic activity, may promote proliferation in AGEs-treated HUVECs independent of the autophagy-lysosome pathway. Meanwhile, CTSD could improve the migration of AGEs-treated HUVECs regardless of its enzymatic activity.

  20. Inhibition of notch signaling in glioblastoma targets cancer stem cells via an endothelial cell intermediate.

    PubMed

    Hovinga, Koos E; Shimizu, Fumiko; Wang, Rong; Panagiotakos, Georgia; Van Der Heijden, Maartje; Moayedpardazi, Hamideh; Correia, Ana Sofia; Soulet, Denis; Major, Tamara; Menon, Jayanthi; Tabar, Viviane

    2010-06-01

    Glioblastoma multiforme (GBM) is a highly heterogeneous malignant tumor. Recent data suggests the presence of a hierarchical organization within the GBM cell population that involves cancer cells with stem-like behavior, capable of repopulating the tumor and contributing to its resistance to therapy. Tumor stem cells are thought to reside within a vascular niche that provides structural and functional support. However, most GBM studies involve isolated tumor cells grown under various culture conditions. Here, we use a novel three-dimensional organotypic "explant" system of surgical GBM specimens that preserves cytoarchitecture and tumor stroma along with tumor cells. Notch inhibition in explants results in decreased proliferation and self-renewal of tumor cells but is also associated with a decrease in endothelial cells. When endothelial cells are selectively eliminated from the explants via a toxin conjugate, we also observed a decrease in self-renewal of tumor stem cells. These findings support a critical role for tumor endothelial cells in GBM stem cell maintenance, mediated at least in part by Notch signaling. The explant system further highlighted differences in the response to radiation between explants and isolated tumor neurospheres. Combination treatment with Notch blockade and radiation resulted in a substantial decrease in proliferation and in self-renewal in tumor explants while radiation alone was less effective. This data suggests that the Notch pathway plays a critical role in linking angiogenesis and cancer stem cell self-renewal and is thus a potential therapeutic target. Three-dimensional explant systems provide a novel approach for the study of tumor and microenvironment interactions.

  1. MiR-630 Inhibits Endothelial-Mesenchymal Transition by Targeting Slug in Traumatic Heterotopic Ossification

    PubMed Central

    Sun, Yangbai; Cai, Jiangyu; Yu, Shiyang; Chen, Shuai; Li, Fengfeng; Fan, Cunyi

    2016-01-01

    Heterotopic ossification (HO) is the abnormal formation of mature bone in extraskeletal soft tissues that occurs as a result of inflammation caused by traumatic injury or associated with genetic mutation. Despite extensive research to identify the source of osteogenic progenitors, the cellular origins of HO are controversial and the underlying mechanisms, which are important for the early detection of HO, remain unclear. Here, we used in vitro and in vivo models of BMP4 and TGF-β2-induced HO to identify the cellular origin and the mechanisms mediating the formation of ectopic bone in traumatic HO. Our results suggest an endothelial origin of ectopic bone in early phase of traumatic HO and indicate that the inhibition of endothelial-mesenchymal transition by miR-630 targeting Slug plays a role in the formation of ectopic bone in HO. A matched case-control study showed that miR-630 is specifically downregulated during the early stages of HO and can be used to distinguish HO from other processes leading to bone formation. Our findings suggest a potential mechanism of post-traumatic ectopic bone formation and identify miR-630 as a potential early indicator of HO. PMID:26940839

  2. Elevated vascular endothelial cell growth factor affects mesocardial morphogenesis and inhibits normal heart bending.

    PubMed

    Drake, Christopher J; Wessels, Andy; Trusk, Tom; Little, Charles D

    2006-01-01

    Signaling by means of vascular endothelial cell growth factor (VEGF) and its receptors (VEGFRs) is required for cardiovascular development. To examine how VEGF/VEGFR receptor signaling affects early endocardial cell behavior, embryonic quail hearts were subjected to elevated VEGF165 levels (five- to nine-somite stage). Primitive embryonic hearts microinjected with recombinant human (rh)VEGF165 exhibit several distinct malformations compared with hearts in untreated embryos: the endocardial tube is malformed with tortuous cords and folds surrounded by a diminished cardiac jelly space, and the lumens of affected hearts are conspicuously reduced. Furthermore, the embryonic heart fails to loop properly. Inhibition of bending is accompanied by an apparent failure of the dorsal mesocardium to atrophy--an event thought to be necessary for heart bending. Instead of atrophy, VEGF-treated mesocardia exhibit a marked increased in the number of resident endothelial cells. Collectively, the data suggest that the abnormally robust mesocardia in VEGF-treated hearts impede the mechanical deformation required for normal heart bending. We conclude that the excessive VEGF signaling culminates in a physical or biomechanical mechanism that acts over a wide, tissue-level, length scale to cause a severe developmental defect--failure of heart bending. 2005 Wiley-Liss, Inc.

  3. Inhibition of telomerase in the endothelial cells disrupts tumor angiogenesis in glioblastoma xenografts.

    PubMed

    Falchetti, Maria Laura; Mongiardi, Maria Patrizia; Fiorenzo, Paolo; Petrucci, Giovanna; Pierconti, Francesco; D'Agnano, Igea; D'Alessandris, Giorgio; Alessandri, Giulio; Gelati, Maurizio; Ricci-Vitiani, Lucia; Maira, Giulio; Larocca, Luigi Maria; Levi, Andrea; Pallini, Roberto

    2008-03-15

    Tumor angiogenesis is a complex process that involves a series of interactions between tumor cells and endothelial cells (ECs). In vitro, glioblastoma multiforme (GBM) cells are known to induce an increase in proliferation, migration and tube formation by the ECs. We have previously shown that in human GBM specimens the proliferating ECs of the tumor vasculature express the catalytic component of telomerase, hTERT, and that telomerase can be upregulated in human ECs by exposing these cells to GBM in vitro. Here, we developed a controlled in vivo assay of tumor angiogenesis in which primary human umbilical vascular endothelial cells (HUVECs) were subcutaneously grafted with or without human GBM cells in immunocompromised mice as Matrigel implants. We found that primary HUVECs did not survive in Matrigel implants, and that telomerase upregulation had little effect on HUVEC survival. In the presence of GBM cells, however, the grafted HUVECs not only survived in Matrigel implants but developed tubule structures that integrated with murine microvessels. Telomerase upregulation in HUVECs enhanced such effect. More importantly, inhibition of telomerase in HUVECs completely abolished tubule formation and greatly reduced survival of these cells in the tumor xenografts. Our data demonstrate that telomerase upregulation by the ECs is a key requisite for GBM tumor angiogenesis. (c) 2007 Wiley-Liss, Inc.

  4. Flavonoids from the leaves of Carya cathayensis Sarg. inhibit vascular endothelial growth factor-induced angiogenesis.

    PubMed

    Tian, Sha-Sha; Jiang, Fu-Sheng; Zhang, Kun; Zhu, Xue-Xin; Jin, Bo; Lu, Jin-Jian; Ding, Zhi-Shan

    2014-01-01

    The total flavonoids (TFs) were isolated from the leaves of Carya cathayensis Sarg. (LCC), a well-known Chinese medicinal herb commercially cultivated in Tianmu Mountain district, a cross area of Zhejiang and Anhui provinces in China. Five flavonoids, i.e. cardamonin, pinostrobin chalcone (PC), wogonin, chrysin, and pinocembrin were the main components of the TFs. The TFs and these pure compounds suppressed vascular endothelial growth factor (VEGF)-induced angiogenesis as detected in the mouse aortic ring assay, and cardamonin showed the best effect among them. To further elucidate the mechanisms for suppressing angiogenesis of these flavonoids, assays of VEGF-induced proliferation and migration in human umbilical vein endothelial cells (HUVECs) were performed. The TFs, cardamonin, pinocembrin, and chrysin obviously suppressed both VEGF-induced HUVEC proliferation and migration. However, PC and wogonin not only slightly inhibited VEGF-induced proliferation but also remarkably suppressed those of migration in HUVECs. Our further study showed that cardamonin decreased the phosphorylation of ERK and AKT induced by VEGF with a dose-dependent manner in HUVECs. Our findings indicate that the TFs and these pure flavonoids may become potential preventive and/or therapeutic agents against angiogenesis-related diseases.

  5. Endothelial nitric oxide synthase activation through obacunone-dependent arginase inhibition restored impaired endothelial function in ApoE-null mice.

    PubMed

    Yoon, Jeongyeon; Park, Minjin; Lee, Jeong hyung; Min, Byung Sun; Ryoo, Sungwoo

    2014-03-01

    Endothelial arginase constrains the activity of endothelial nitric oxide synthase (eNOS) by substrate depletion and reduces nitric oxide bioavailability. During the screening course of arginase inhibitor, we found obacunone as an arginase inhibitor. We tested the hypothesis that obacunone regulates vascular endothelial NO production. Obacunone incubation inhibited arginase I and II activities in liver and kidney lysates, respectively, in dose-dependent manner. Obacunone reciprocally increased nitrite/nitrate (NOx) production in HUVECs. In isolated aortic rings, obacunone increased intracellular l-arginine concentration and enhanced eNOS coupling, leading to increased NO and decreased superoxide production, with no changes in protein expression. Vasoconstriction response to U46619 was attenuated in obacunone-treated aortic vessels compared to that in untreated vessels. Endothelium-dependent vasorelaxant response to acetylcholine was significantly increased in obacunone-treated vessels and was modulated by the NO-dependent signaling cascade. The dose-dependent vasorelaxant response to Ach was reduced in the aortic vessels of ApoE-/- mice fed a high-cholesterol diet. Obacunone incubation increased vasorelaxation to the level of a WT mouse, although the endothelium-independent response to sodium nitroprusside was identical among the groups. Therefore, obacunone may help treat cardiovascular diseases derived from endothelial dysfunction and may be useful for designing pharmaceutical compounds.

  6. Magnetic fluid hyperthermia inhibits the growth of breast carcinoma and downregulates vascular endothelial growth factor expression.

    PubMed

    Wang, Guihua; Xu, Derong; Chai, Qin; Tan, Xiaolang; Zhang, Yu; Gu, Ning; Tang, Jintian

    2014-05-01

    The application of magnetic fluid hyperthermia (MFH) with nanoparticles has been shown to inhibit tumor growth in several animal models. However, the feasibility of using MFH in vivo to treat breast cancer is uncertain, and the mechanism is unclear. In the present study, it was observed that the intratumoral administration of MFH induced hyperthermia significantly in rats with Walker-265 breast carcinomas. The hyperthermia treatment with magnetic nanoparticles inhibited tumor growth in vivo and promoted the survival of the tumor-bearing rats. Furthermore, it was found that MFH treatment downregulated the protein expression of vascular endothelial growth factor (VEGF) in the tumor tissue, as observed by immunohistochemistry. MFH treatment also decreased the gene expression of VEGF and its receptors, VEGF receptor 1 and 2, and inhibited angiogenesis in the tumor tissues. Taken together, these results indicate that the application of MFH with nanoparticles is feasible for the treatment of breast carcinoma. The MFH-induced downregulation of angiogenesis may also contribute to the induction of an anti-tumor effect.

  7. Oxidative stress inhibits caveolin-1 palmitoylation and trafficking in endothelial cells

    NASA Technical Reports Server (NTRS)

    Parat, Marie-Odile; Stachowicz, Rafal Z.; Fox, Paul L.

    2002-01-01

    During normal and pathological conditions, endothelial cells (ECs) are subjected to locally generated reactive oxygen species, produced by themselves or by other vessel wall cells. In excess these molecules cause oxidative injury to the cell but at moderate levels they might modulate intracellular signalling pathways. We have investigated the effect of oxidative stress on the palmitoylation and trafficking of caveolin-1 in bovine aortic ECs. Exogenous H2O2 did not alter the intracellular localization of caveolin-1 in ECs. However, metabolic labelling experiments showed that H2O2 inhibited the trafficking of newly synthesized caveolin-1 to membrane raft domains. Several mechanisms potentially responsible for this inhibition were examined. Impairment of caveolin-1 synthesis by H2O2 was not responsible for diminished trafficking. Similarly, the inhibition was independent of H2O2-induced caveolin-1 phosphorylation as shown by the markedly different concentration dependences. We tested the effect of H2O2 on palmitoylation of caveolin-1 by the incorporation of [3H]palmitic acid. Exposure of ECs to H2O2 markedly inhibited the palmitoylation of caveolin-1. Comparable inhibition was observed after treatment of cells with H2O2 delivered either as a bolus or by continuous delivery with glucose and glucose oxidase. Kinetic studies showed that H2O2 did not alter the rate of caveolin-1 depalmitoylation but instead decreased the 'on-rate' of palmitoylation. Together these results show for the first time the modulation of protein palmitoylation by oxidative stress, and suggest a cellular mechanism by which stress might influence caveolin-1-dependent cell activities such as the concentration of signalling proteins and cholesterol trafficking.

  8. Interleukin-35 Inhibits Endothelial Cell Activation by Suppressing MAPK-AP-1 Pathway.

    PubMed

    Sha, Xiaojin; Meng, Shu; Li, Xinyuan; Xi, Hang; Maddaloni, Massimo; Pascual, David W; Shan, Huimin; Jiang, Xiaohua; Wang, Hong; Yang, Xiao-feng

    2015-07-31

    Vascular response is an essential pathological mechanism underlying various inflammatory diseases. This study determines whether IL-35, a novel responsive anti-inflammatory cytokine, inhibits vascular response in acute inflammation. Using a mouse model of LPS-induced acute inflammation and plasma samples from sepsis patients, we found that IL-35 was induced in the plasma of mice after LPS injection as well as in the plasma of sepsis patients. In addition, IL-35 decreased LPS-induced proinflammatory cytokines and chemokines in the plasma of mice. Furthermore, IL-35 inhibited leukocyte adhesion to the endothelium in the vessels of lung and cremaster muscle and decreased the numbers of inflammatory cells in bronchoalveolar lavage fluid. Mechanistically, IL-35 inhibited the LPS-induced up-regulation of endothelial cell (EC) adhesion molecule VCAM-1 through IL-35 receptors gp130 and IL-12Rβ2 via inhibition of the MAPK-activator protein-1 (AP-1) signaling pathway. We also found that IL-27, which shares the EBI3 subunit with IL-35, promoted LPS-induced VCAM-1 in human aortic ECs and that EBI3-deficient mice had similar vascular response to LPS when compared with that of WT mice. These results demonstrated for the first time that inflammation-induced IL-35 inhibits LPS-induced EC activation by suppressing MAPK-AP1-mediated VCAM-1 expression and attenuates LPS-induced secretion of proinflammatory cytokines/chemokines. Our results provide insight into the control of vascular inflammation by IL-35 and suggest that IL-35 is an attractive novel therapeutic reagent for sepsis and cardiovascular diseases.

  9. Delivery of small interfering RNA for inhibition of endothelial cell apoptosis by hypoxia and serum deprivation

    SciTech Connect

    Cho, Seung-Woo; Hartle, Lauren; Son, Sun Mi; Yang, Fan; Goldberg, Michael; Xu, Qiaobing; Langer, Robert; Anderson, Daniel G.

    2008-11-07

    RNA interference (RNAi) for anti-angiogenic or pro-apoptotic factors in endothelial cells (ECs) has great potential for the treatment of ischemic diseases by promoting angiogenesis or inhibiting apoptosis. Here, we report the utility of small interfering RNA (siRNA) in inhibiting EC apoptosis induced by tumor necrosis factor-{alpha} (TNF-{alpha}). siRNA was designed and synthesized targeting tumor necrosis factor-{alpha} receptor-1 (TNFR-1) and Src homology 2 domain-containing protein tyrosine phosphatase-1 (SHP-1). Human umbilical vein endothelial cells (HUVECs) were cultured under in vitro hypoxic and serum-deprived conditions to simulate in vivo ischemic conditions. Two days after liposomal delivery of siRNA targeting TNFR-1 and SHP-1, significant silencing of each target (TNFR-1; 76.5% and SHP-1; 97.2%) was detected. Under serum-deprived hypoxic (1% oxygen) conditions, TNF-{alpha} expression in HUVECs increased relative to normoxic (20% oxygen) and serum-containing conditions. Despite enhanced TNF-{alpha} expression, suppression of TNFR-1 or SHP-1 by siRNA delivery not only enhanced expression of angiogenic factors (KDR/Flk-1 and eNOS) and anti-apoptotic factor (Bcl-xL) but also reduced expression of a pro-apoptotic factor (Bax). Transfection of TNFR-1 or SHP-1 siRNA significantly decreased the HUVEC apoptosis while significantly enhancing HUVEC proliferation and capillary formation. The present study demonstrates that TNFR-1 and SHP-1 may be useful targets for the treatment of myocardial or hindlimb ischemia.

  10. Inhibition of volume-activated chloride currents in endothelial cells by chromones.

    PubMed Central

    Heinke, S.; Szücs, G.; Norris, A.; Droogmans, G.; Nilius, B.

    1995-01-01

    1. We have studied the effects of the reported chloride channel blocker, sodium cromoglycate, on volume-activated Cl- currents in endothelial cells from bovine pulmonary artery by means of the whole-cell patch clamp technique. Cl- currents were activated by challenging the cells with a hypotonic extracellular solution of 60% of the normal osmolarity. 2. Half maximal activation of the current at +95 mV occurred after exposure of the cells for 148 +/- 10 s (n = 6) to hypotonic solution (HTS). At the same membrane potential but in the presence of 100 microM sodium cromoglycate (disodium-1,3-bis (2'-carboxylate-chromone-5'-yloxy)-2-hydroxy-propane) activation was delayed (253 +/- 25 s, n = 6) and the maximal current amplitude was reduced to 63 +/- 7% of the control (n = 13). 3. In comparison, an equimolar concentration of NPPB (5-nitro-2(3-phenyl) propylamino-benzoic acid), another Cl- channel blocker, completely blocked the volume-activated current in less than 20 s. 4. Sodium cromoglycate, applied at the time when the HTS-induced current was completely activated, dose-dependently inhibited this current with a concentration for half maximal inhibition of 310 +/- 70 microM. Data for nedocromil sodium were not significantly different from those for sodium cromoglycate. 5. Sodium cromoglycate, loaded into the endothelial cells via the patch pipette in ruptured patches, resulted in a decline of the HTS activated current with a time course that was compatible with diffusion of the compound from the pipette into the cell.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8564197

  11. Increase in E-selectin expression in umbilical vein endothelial cells by anticancer drugs and inhibition by cimetidine.

    PubMed

    Kawase, Jin; Ozawa, Soji; Kobayashi, Kenichi; Imaeda, Yoshihiro; Umemoto, Shunji; Matsumoto, Sumio; Ueda, Masakazu

    2009-12-01

    E-selectin is expressed on the surfaces of stimulated vascular endothelial cells and is sometimes involved in cancer cell metastasis. The H2-receptor antagonist cimetidine inhibits the increase in E-selectin expression on vascular endothelial cells that is induced by interleukin-1beta (IL-1beta) and cimetidine. It also inhibits the adhesion of sialyl-Lewis-antigen-positive cancer cells to vascular endothelial cells, ultimately inhibiting hematogenous metastasis. Anticancer drugs are essential to cancer therapy, but whether they can alter the expression of E-selectin in vascular endothelial cells remains unclear. Whether cimetidine inhibits the expression of E-selectin in the same manner in the presence or absence of anticancer drugs also remains unknown. Human umbilical vein endothelial cells were cultured with 5-fluorouracil (5-FU), doxorubicin (DXR), cisplatin (CDDP), or IL-1beta and with or without cimetidine. The expression of E-selectin at the mRNA and protein levels was then determined using quantitative reverse transcription-polymerase chain reaction and immunohistochemical staining, respectively. The E-selectin mRNA level increased in cells exposed to 5-FU, DXR, or CDDP, but the addition of cimetidine had no effect on the E-selectin mRNA level. The expression of E-selectin protein was also significantly higher after the addition of 5-FU, DXR, or CDDP, compared with that of a negative control. However, when cimetidine was added prior to the addition of 5-FU, DXR, or CDDP, the expression of E-selectin was significantly suppressed. Thus, cimetidine significantly inhibited the expression of E-selectin at the protein level without affecting its expression at the mRNA level in cells treated with anticancer drugs. In conclusion, anticancer drugs increased the expression of E-selectin and this increase was inhibited by cimetidine. These findings suggest that the administration of cimetidine during treatment with anticancer drugs might be useful for preventing

  12. Soy isoflavones attenuate human monocyte adhesion to endothelial cell-specific CD54 by inhibiting monocyte CD11a.

    PubMed

    Nagarajan, Shanmugam; Stewart, Bradford W; Badger, Thomas M

    2006-09-01

    Soy-based diets have been shown to protect against the development of atherosclerosis; however, the underlying mechanism(s) remain unknown. Interaction between activated monocytes and inflamed endothelial cells is an early event in atherogenesis. Therefore, we examined whether treatment of monocytes with soy phytochemicals could inhibit their adhesion to the endothelial cell-specific protein, CD54, a key factor in monocyte adhesion. Female Sprague-Dawley rats were fed AIN-93G diets containing soy protein isolate or casein. Sera from soy-fed rats inhibited CD54-dependent monocyte adhesion, whereas sera from casein-fed rats did not. To determine whether isoflavones in the sera of soy-fed rats were involved in this inhibition, monocytes were preincubated with soy isoflavones. Isoflavone treatment inhibited monocyte adhesion to CD54 protein, as well as to endothelial cells expressing CD54. Monocyte expression of CD11a, the cognate receptor for CD54, was unaffected by isoflavones. However, binding of the activation epitope-specific antibody mAb24, which binds specifically to the active form of CD11a, was significantly lower in soy isoflavone-treated monocytes than in media-treated cells. These findings suggest that inhibition of CD54-dependent monocyte adhesion by soy isoflavones is mediated in part by affinity regulation of CD11a. Inhibition of monocyte adhesion to endothelial cells by isoflavones resulted in reduced expression of the inflammatory cytokines IL-6 and IL-8. Collectively, these data suggest that the athero-protective effect of soy diets may be mediated by blocking monocyte-endothelial cell interaction.

  13. [Inhibition of tumor growth by a peptide fusion protein binding to vascular endothelial growth factor receptor Flt-1].

    PubMed

    Lei, Hetian; Shou, Chengchao; Wu, Jian; Liu, Xiaoying; He, Luowen; Liu, Meisheng; Guo, Qi; Jiang, Beihai

    2002-10-10

    Investigating the bio-activities of peptides selected from phage display peptide library with vascular endothelial growth factor receptor Flt-1. Activities of DHFR-F56/F90 binding to human ubilial vein endothelial cells were detected by immunocytochemistry, and the activity of antiangiogenesis was determined with chick embryo chorioallantoric membrane (CAM) assay. Balb/c nude mice were used as model to detect the activity of DHFR-F56/F90 on inhibiting tumor growth, and immunohistochemistry was employed to determine the localization of the DHFR-F56/F90 in tumor. DHFR-F56/F90 can bind to HUVEC, and DHFR-F56 inhibite angiogenesis in CAM. Meanwhile DHFR-F56 can bind with tumor cells, induce tumor necrosis and inhibit tumor growth in vivo. The peptide F56 is an effective antagonist of VEGF binding to Flt-1 and has a potent utility in antiangiogenesis and inhibiting tumor growth.

  14. Inhibition of endocytosis exacerbates TNF-α-induced endothelial dysfunction via enhanced JNK and p38 activation.

    PubMed

    Choi, Hyehun; Nguyen, Hong N; Lamb, Fred S

    2014-04-15

    Tumor necrosis factor-α (TNF-α) is a pro-inflammatory cytokine that causes endothelial dysfunction. Endocytosis of TNF-α receptors (TNFR) precedes endosomal reactive oxygen species (ROS) production, which is required for NF-κB activation in vascular smooth muscle cells. It is unknown how endocytosis of TNFRs impacts signaling in endothelial cells. We hypothesized that TNF-α-induced endothelial dysfunction is induced by both endosomal and cell surface events, including NF-κB and mitogen-activated protein kinases (MAPKs) activation, and endocytosis of the TNFR modifies signaling. Mesenteric artery segments from C57BL/6 mice were treated with TNF-α (10 ng/ml) for 22 h in tissue culture, with or without signaling inhibitors (dynasore for endocytosis, SP600125 for JNK, SB203580 for p38, U0126 for ERK), and vascular function was assessed. Endothelium-dependent relaxation to acetylcholine (ACh) was impaired by TNF-α, and dynasore exacerbated this, whereas JNK or p38 inhibition prevented these effects. In cultured endothelial cells from murine mesenteric arteries, dynasore potentiated JNK and p38 but not ERK phosphorylation and promoted cell death. NF-κB activation by TNF-α was decreased by dynasore. JNK inhibition dramatically increased both the magnitude and duration of TNF-α-induced NF-κB activation and potentiated intercellular adhesion molecule-1 (ICAM-1) activation. Dynasore still inhibited NF-κB activation in the presence of SP600125. Thus TNF-α-induced endothelial dysfunction is both JNK and p38 dependent. Endocytosis modulates the balance of NF-κB and MAPK signaling, and inhibition of NF-κB activation by JNK limits this pro-proliferative signal, which may contribute to endothelial cell death in response to TNF-α.

  15. A natural small molecule harmine inhibits angiogenesis and suppresses tumour growth through activation of p53 in endothelial cells.

    PubMed

    Dai, Fujun; Chen, Yihua; Song, Yajuan; Huang, Li; Zhai, Dong; Dong, Yanmin; Lai, Li; Zhang, Tao; Li, Dali; Pang, Xiufeng; Liu, Mingyao; Yi, Zhengfang

    2012-01-01

    Activation of p53 effectively inhibits tumor angiogenesis that is necessary for tumor growth and metastasis. Reactivation of the p53 by small molecules has emerged as a promising new strategy for cancer therapy. Several classes of small-molecules that activate the p53 pathway have been discovered using various approaches. Here, we identified harmine (β-carboline alkaloid) as a novel activator of p53 signaling involved in inhibition of angiogenesis and tumor growth. Harmine induced p53 phosphorylation and disrupted the p53-MDM2 interaction. Harmine also prevented p53 degradation in the presence of cycloheximide and activated nuclear accumulation of p53 followed by increasing its transcriptional activity in endothelial cells. Moreover, harmine not only induced endothelial cell cycle arrest and apoptosis, but also suppressed endothelial cell migration and tube formation as well as induction of neovascularity in a mouse corneal micropocket assay. Finally, harmine inhibited tumor growth by reducing tumor angiogenesis, as demonstrated by a xenograft tumor model. Our results suggested a novel mechanism and bioactivity of harmine, which inhibited tumor growth by activating the p53 signaling pathway and blocking angiogenesis in endothelial cells.

  16. Inhibition of major integrin αV β3 reduces Staphylococcus aureus attachment to sheared human endothelial cells.

    PubMed

    McDonnell, C J; Garciarena, C D; Watkin, R L; McHale, T M; McLoughlin, A; Claes, J; Verhamme, P; Cummins, P M; Kerrigan, S W

    2016-12-01

    Essentials Staphylococcus aureus (S. aureus) binds and impairs function of vascular endothelial cells (EC). We investigated the molecular signals triggered by S. aureus adhesion to EC. Inhibition of the EC integrin αVβ3 reduces S. aureus binding and rescues EC function. αVβ3 blockade represents an attractive target to treat S. aureus bloodborne infections.

  17. Role of lysophosphatidylcholine in the inhibition of endothelial cell motility by oxidized low density lipoprotein.

    PubMed Central

    Murugesan, G; Fox, P L

    1996-01-01

    Endothelial cell (EC) movement is required for the development and repair of blood vessels. We have previously shown that LDL oxidized by transition metals almost completely suppressed the wound-healing migratory response of vascular EC in vitro. We now report that lysophosphatidylcholine (lysoPC), a lipid component of oxidized LDL, has an important role in the antimigratory activity of the lipoprotein. Purified 1-palmitoyl lysoPC inhibited movement with a half-maximal activity at 12-15 micrometers, and near complete inhibition at 20 micrometers; the inhibitory concentration of lysoPC was consistent with its abundance in oxidized LDL. The inhibition was not due to cytotoxicity since protein synthesis was unaffected and since EC movement was restored after removal of lysoPC. Lysophospholipid activity was dependent on lipid structure. LysoPC's containing 1-position C16 or C18 saturated fatty acids were antimigratory, but those containing C < or = 14 saturated fatty acids or polyunsaturated fatty acids were not. The activity of 1-palmitoyl lysolipids with various head groups was examined. Lysophosphatidylinositol was more antimigratory than lysophosphatidylglycerol and lysophosphatidylcholine, which were more potent than lysophosphatidylserine and lysophosphatidylethanolamine. Monoglyceride was inactive while lysophosphatidate had promigratory activity. These results are consistent with head group size rather than charge as a critical determinant of activity. To show that lysophospholipids within an intact lipoprotein were active, LDL was treated with bee venom phospholipase A2 (PLA2). The modified lipoprotein inhibited EC movement to the same extent as iron-oxidized LDL and antimigratory activity correlated with the amount of lysoPC formed. To determine antimigratory activity of lysoPC present in oxidized LDL, lipid extracts from oxidized LDL were fractionated by normal phase HPLC. The fraction comigrating with lysoPC had nearly the same activity as the total extract

  18. Inhibition of angiogenesis by vitamin D-binding protein: characterization of anti-endothelial activity of DBP-maf.

    PubMed

    Kalkunte, Satyan; Brard, Laurent; Granai, Cornelius O; Swamy, Narasimha

    2005-01-01

    Angiogenesis is a complex process involving coordinated steps of endothelial cell activation, proliferation, migration, tube formation and capillary sprouting with participation of intracellular signaling pathways. Regulation of angiogenesis carries tremendous potential for cancer therapy. Our earlier studies showed that vitamin D-binding protein-macrophage activating factor (DBP-maf) acts as a potent anti-angiogenic factor and inhibits tumor growth in vivo. The goal of this investigation was to understand the effect of DBP-maf on human endothelial cell (HEC) and the mechanism of angiogenesis inhibition. DBP-maf inhibited human endothelial cell (HEC) proliferation by inhibiting DNA synthesis (IC(50) = 7.8 +/- 0.15 microg/ml). DBP-maf significantly induced S- and G0/G1-phase arrest in HEC in 72 h. DBP-maf potently blocked VEGF-induced migration, tube-formation of HEC in a dose dependent manner. In addition, DBP-maf inhibited growth factor-induced microvessel sprouting in rat aortic ring assay. Moreover, DBP-maf inhibited VEGF signaling by decreasing VEGF-mediated phosphorylation of VEGFR-2 and ERK1/2, a downstream target of VEGF signaling cascade. However, Akt activation was not affected. These studies collectively demonstrate that DBP-maf inhibits angiogenesis by blocking critical steps such as HEC proliferation, migration, tube formation and microvessel sprouting. DBP-maf exerts its effect by inhibiting VEGR-2 and ERK1/2 signaling cascades. Understanding the cellular and molecular mechanisms of anti-endothelial activity of DBP-maf will allow us to develop it as an angiogenesis targeting novel drug for tumor therapy.

  19. Andrographolide inhibits the adhesion of gastric cancer cells to endothelial cells by blocking E-selectin expression.

    PubMed

    Jiang, Cheng-Gang; Li, Jia-Bin; Liu, Fu-Rong; Wu, Tao; Yu, Miao; Xu, Hui-Mian

    2007-01-01

    Andrographolide, an active component isolated from the Chinese official herbal Andrographis paniculata, has recently been reported to have anticancer activity. However the molecular mechanism responsible for its anticancer action has not been fully defined. In this study, we investigated the effect of andrographolide on the adhesion of gastric cancer cells to the activated endothelial cells and the expression of some cell adhesion molecules. Human endothelial cells were preincubated with andrographolide for 6 h and then incubated with the cytokine tumor necrosis factor for 4 h. Endothelial surface expression of E-selectin was evaluated by flow cytometry, immunostaining and ELISA. Further, we investigated E-selectin mRNA expression by RT-PCR. Surface expression of sialyl Lewis(X) of three gastric cancer cell lines (SGC7901, MGC803, BGC823) and a normal gastric epithelial cell line GES-1 was evaluated by flow cytometry and immunostaining. Adherence of CFSE-labeled gastric cancer cells and GES-1 cells to endothelial cell monolayers was then determined. Andrographolide significantly reduced E-selectin expression of activated endothelial cells, and inhibited the E-selectin expression on mRNA level. Three gastric cancer cell lines expressed high levels of sialyl Lewis(X), whereas GES-1 did not. Andrographolide also significantly decreased gastric cancer cells adherence to stimulated endothelial cells. The inhibition of E-selectin expression corresponded to the reduction of tumor cell adherence. The effects of andrographolide on tumor adhesion were almost nullified by pre-incubation with E-selectin and sialyl Lewis(X) antibody. These findings demonstrate that andrographolide suppresses the adhesion of gastric cancer cells which express high level sialyl Lewis(X) to human vascular endothelial cells by blocking E-selectin expression and, thus, may represent a candidate therapeutic agent for cancer.

  20. Glycosylation inhibitors efficiently inhibit P-selectin-mediated cell adhesion to endothelial cells.

    PubMed

    Ghoshal, Pushpankur; Rajendran, Mythilypriya; Odo, Nadine; Ikuta, Tohru

    2014-01-01

    Adhesion molecules play a critical role in the adhesive interactions of multiple cell types in sickle cell disease (SCD). We previously showed that anti-P-selectin aptamer efficiently inhibits cell adhesion to endothelial cells (ECs) and permits SCD mice to survive hypoxic stress. In an effort to discover new mechanisms with which to inhibit P-selectin, we examined the role of glycosylation. P-selectin is a 90 kDa protein but was found to migrate as 90 and 140 kDa bands on gel electrophoresis. When P-selectin isolated from ECs was digested with peptide N-glycosidase F, but not O-glycosidase, the 140 kDa band was lost and the 90 kDa band was enhanced. Treatment of ECs with tunicamycin, an N-glycosylation inhibitor, suppressed CD62P (P-selectin) expression on the cell surface as well as the 140 kDa form in the cytoplasm. These results indicate that the 140 kDa band is N-glycosylated and glycosylation is critical for cell surface expression of P-selectin in ECs. Thrombin, which stimulates P-selectin expression on ECs, induced AKT phosphorylation, whereas tunicamycin inhibited AKT phosphorylation, suggesting that AKT signaling is involved in the tunicamycin-mediated inhibition of P-selectin expression. Importantly, the adhesion of sickle red blood cells (sRBCs) and leukocytes to ECs induced by thrombin or hypoxia was markedly inhibited by two structurally distinct glycosylation inhibitors; the levels of which were comparable to that of a P-selectin monoclonal antibody which most strongly inhibited cell adhesion in vivo. Knockdown studies of P-selectin using short-hairpin RNAs in ECs suppressed sRBC adhesion, indicating a legitimate role for P-selectin in sRBC adhesion. Together, these results demonstrate that P-selectin expression on ECs is regulated in part by glycosylation mechanisms and that glycosylation inhibitors efficiently reduce the adhesion of sRBCs and leukocytes to ECs. Glycosylation inhibitors may lead to a novel therapy which inhibits cell adhesion in SCD.

  1. N-ethylmaleimide-sensitive factor siRNA inhibits the release of Weibel-Palade bodies in endothelial cells

    PubMed Central

    Zhou, Yong; Yang, Shui-Xiang; Yue, Yu-Nan; Wei, Xiao-Fei; Liu, Yan

    2016-01-01

    The aim of the present study was to examine the effect of small interfering RNA (siRNA) methods on the expression of N-ethylmaleimide sensitive factor (NSF) and Weibel-Palade body (WPB) release in endothelial cells. A small hairpin RNA (shRNA), mediated with an adenovirus vector, was designed to target the N-terminal functional area of NSF. Subsequently, viruses were transfected into human aortic endothelial cells. The mRNA and protein expression levels of NSF were detected using reverse transcription-quantitative polymerase chain reaction and Western blot analyses, respectively, and the release of WPBs in the endothelial cells was examined using immunofluorescence. The mRNA expression of NSF in the endothelial cells, which were transfected with the adenoviruses carrying the NSF-shRNA was significantly decreased, compared with the negative control group (P=0.035) and blank control group (P=0.02). In addition, the mRNA expression of NSF was gradually decreased as duration increased; there were marked differences between the 24, 48 and 72 h groups (P<0.05). The protein expression of NSF was significantly decreased in the experimental group, compared with the negative control group (P=0.004) and blank control group (P=0.031), however, no difference was observed between the negative control and blank control groups (P=0.249). The immunofluorescence staining showed that the release of WPBs in the endothelial cells induced with thrombin was inhibited markedly following transfection with the virus carrying the NSF-shRNA. Therefore NSF-siRNA inhibited the mRNA and protein expression levels of NSF, and inhibited the release of WPBs in endothelial cells induced with thrombin. These results suggested that NSF-siRNA may be valuable for preventing and treating atherosclerosis and acute coronary syndrome. PMID:27277949

  2. Quercetin inhibits angiogenesis-mediated human retinoblastoma growth by targeting vascular endothelial growth factor receptor.

    PubMed

    Song, Wei; Zhao, Xiaofei; Xu, Jiarui; Zhang, Han

    2017-09-01

    Retinoblastoma (RB) is the most common malignant intraocular cancer in teenagers, occurrence of which depends on the mutation of multiple genes. Among all the signaling pathways involved in the oncogenesis of RB, the process of angiogenesis has been demonstrated to be associated with the local invasive growth and metastasis of this cancer type. Quercetin (Que) is a typical flavonoid and has been reported to inhibit angiogenesis in various types of tumors. In the present study, the effect of Que on RB cells and angiogenesis of RB was evaluated. The human RB Y79 cell line was subjected to treatment with Que of various concentrations. Viability, invasion and migration ability and apoptosis of Y79 cells were subsequently measured to assess the effect of Que on RB cells. In addition, the expression of vascular endothelial growth factor receptor (VEGFR) was also quantified. It was revealed that Que inhibited RB cell growth and invasion in vitro in a dose-dependent manner, with 100 µM Que exhibiting the strongest inhibitory effect. In addition, Que downregulated the expression of VEGFR, which was an indicator of the blockade of angiogenesis in RB by targeting VEGF. The effect of Que on angiogenesis was also observed to be dose-dependent. The results of the present study indicated that Que may be a potential anti-RB therapy due to its anti-angiogenesis effect.

  3. Cabergoline reduces cell viability in non functioning pituitary adenomas by inhibiting vascular endothelial growth factor secretion.

    PubMed

    Gagliano, Teresa; Filieri, Carlo; Minoia, Mariella; Buratto, Mattia; Tagliati, Federico; Ambrosio, Maria Rosaria; Lapparelli, Marcello; Zoli, Matteo; Frank, Giorgio; degli Uberti, Ettore; Zatelli, Maria Chiara

    2013-03-01

    Dopamine (DA) therapy of non-functioning pituitary adenomas (NFA) can result in tumor stabilization and shrinkage. However, the mechanism of action is still unknown. Previous evidence showed that DA can inhibit pituitary vascular endothelial growth factor expression (VEGF), that may be involved in pituitary tumor growth. The aim of our study was to clarify whether VEGF secretion modulation might mediate the effects of DA agonists on cell proliferation in human NFA. We assessed DA receptor subtype 2 (DR2) expression in 20 NFA primary cultures, where we also investigated the effects of a selective DR2 agonist, cabergoline (Cab), on VEGF secretion and on cell viability. All NFA samples expressed α-subunit and DR2 was expressed in 11 samples. In DR2 expressing tumors, Cab significantly reduced cell viability (-25%; P < 0.05) and VEGF secretion (-20%; P < 0.05). These effects were counteracted by treatment with the DA antagonist sulpiride. Cab antiproliferative effects were blocked by VEGF. Our data demonstrate that Cab, via DR2, inhibits cell viability also by reducing VEGF secretion in a selected group of NFA, supporting that DA agonists can be useful in the medical therapy of DR2 expressing NFA.

  4. Gene Therapy Inhibiting Neointimal Vascular Lesion: In vivo Transfer of Endothelial Cell Nitric Oxide Synthase Gene

    NASA Astrophysics Data System (ADS)

    von der Leyen, Heiko E.; Gibbons, Gary H.; Morishita, Ryuichi; Lewis, Neil P.; Zhang, Lunan; Nakajima, Masatoshi; Kaneda, Yasufumi; Cooke, John P.; Dzau, Victor J.

    1995-02-01

    It is postulated that vascular disease involves a disturbance in the homeostatic balance of factors regulating vascular tone and structure. Recent developments in gene transfer techniques have emerged as an exciting therapeutic option to treat vascular disease. Several studies have established the feasibility of direct in vivo gene transfer into the vasculature by using reporter genes such as β-galactosidase or luciferase. To date no study has documented therapeutic effects with in vivo gene transfer of a cDNA encoding a functional enzyme. This study tests the hypothesis that endothelium-derived nitric oxide is an endogenous inhibitor of vascular lesion formation. After denudation by balloon injury of the endothelium of rat carotid arteries, we restored endothelial cell nitric oxide synthase (ec-NOS) expression in the vessel wall by using the highly efficient Sendai virus/liposome in vivo gene transfer technique. ec-NOS gene transfection not only restored NO production to levels seen in normal untreated vessels but also increased vascular reactivity of the injured vessel. Neointima formation at day 14 after balloon injury was inhibited by 70%. These findings provide direct evidence that NO is an endogenous inhibitor of vascular lesion formation in vivo (by inhibiting smooth muscle cell proliferation and migration) and suggest the possibility of ec-NOS transfection as a potential therapeutic approach to treat neointimal hyperplasia.

  5. Direct endothelial junction restoration results in significant tumor vascular normalization and metastasis inhibition in mice

    PubMed Central

    Agrawal, Vijayendra; Maharjan, Sony; Kim, Kyeojin; Kim, Nam-Jung; Son, Jimin; Lee, Keunho; Choi, Hyun-Jung; Rho, Seung-Sik; Ahn, Sunjoo; Won, Moo-Ho; Ha, Sang-Jun; Koh, Gou Young; Kim, Young-Myeong; Suh, Young-Ger; Kwon, Young-Guen

    2014-01-01

    Tumor blood vessels are leaky and immature, which causes inadequate blood supply to tumor tissues resulting in hypoxic microenvironment and promotes metastasis. Here we have explored tumor vessel modulating activity of Sac-1004, a recently developed molecule in our lab, which directly potentiates VE-cadherin-mediated endothelial cell junction. Sac-1004 could enhance vascular junction integrity in tumor vessels and thereby inhibit vascular leakage and enhance vascular perfusion. Improved perfusion enabled Sac-1004 to have synergistic anti-tumor effect on cisplatin-mediated apoptosis of tumor cells. Interestingly, characteristics of normalized blood vessels namely reduced hypoxia, improved pericyte coverage and decreased basement membrane thickness were readily observed in tumors treated with Sac-1004. Remarkably, Sac-1004 was also able to inhibit lung and lymph node metastasis in MMTV and B16BL6 tumor models. This was in correlation with a reduction in epithelial-to-mesenchymal transition of tumor cells with considerable diminution in expression of related transcription factors. Moreover, cancer stem cell population dropped substantially in Sac-1004 treated tumor tissues. Taken together, our results showed that direct restoration of vascular junction could be a significant strategy to induce normalization of tumor blood vessels and reduce metastasis. PMID:24811731

  6. The vascular endothelial growth factor receptor inhibitor PTK787/ZK222584 inhibits aromatase.

    PubMed

    Banerjee, Susana; Zvelebil, Marketa; Furet, Pascal; Mueller-Vieira, Ursula; Evans, Dean B; Dowsett, Mitch; Martin, Lesley-Ann

    2009-06-01

    Endocrine therapy is well established for the treatment of breast cancer, and antiangiogenic agents are showing considerable promise. Targeting the vascular endothelial growth factor (VEGF) and estrogen receptor (ER) signaling pathways concomitantly may provide enhanced therapeutic benefit in ER-positive breast cancer. Therefore, the effects of the VEGF receptor (VEGFR) tyrosine kinase inhibitor PTK787/ZK222584 (PTK/ZK) were investigated using human breast cancer cell lines engineered to express aromatase. As expected in this system, estrogen (E2) or androstenedione induced a proliferative response and increased ER-mediated transcription in ER-positive cell lines expressing aromatase. However, surprisingly, in the presence of androstenedione, PTK/ZK suppressed both the androstenedione-stimulated proliferation and ER-mediated transcription. PTK/ZK alone and in the presence of E2 had no observable effect on proliferation or ER-mediated transcription. These effects result from PTK/ZK having previously unrecognized antiaromatase activity and PTK/ZK being a competitive aromatase inhibitor. Computer-assisted molecular modeling showed that PTK/ZK could potentially bind directly to aromatase. The demonstration that PTK/ZK inhibits aromatase and VEGFR indicates that agents cross-inhibiting two important classes of targets in breast cancer could be developed.

  7. Hydrogen peroxide inhibits exercise-induced increase of circulating stem cells with endothelial progenitor capacity.

    PubMed

    Suvorava, Tatsiana; Kumpf, Stephanie; Rauch, Bernhard H; Dao, Vu Thao-Vi; Adams, Volker; Kojda, Georg

    2010-02-01

    The number of circulating stem cells with endothelial progenitor capacity (EPCs) inversely correlates with the number of cardiovascular risk factors. In this study we sought to investigate the effects of vascular H(2)O(2) on circulating EPC levels. In C57BL/6 mice 3 weeks of freely moving or forced physical activity or voluntary exercise failed to increase circulating EPCs defined as double positive for Flk-1 and CD34, CD133 or Sca-1. Likewise, neither insertion of additional genes encoding for catalase (cat(++)) or eNOS nor eNOS knock-out changed EPCs in resting mice. In striking contrast, inhibition of catalase by aminotriazole strongly reduced circulating EPCs in sedentary cat(++) and their transgen-negative littermates (cat(n)), while forced or voluntary exercise training of cat(++) mice significantly increased the number of circulating EPCs. The latter effect was completely inhibitable by aminotriazole. These data suggest that endogenous vascular H(2)O(2) likely contributes to the impairment of important stem cell-induced vascular repair mechanisms in cardiovascular disease.

  8. Local acting Sticky-trap inhibits vascular endothelial growth factor dependent pathological angiogenesis in the eye

    PubMed Central

    Michael, Iacovos P; Westenskow, Peter D; Hacibekiroglu, Sabiha; Greenwald, Alissa Cohen; Ballios, Brian G; Kurihara, Toshihide; Li, Zhijie; Warren, Carmen M; Zhang, Puzheng; Aguilar, Edith; Donaldson, Laura; Marchetti, Valentina; Baba, Takeshi; Hussein, Samer M; Sung, Hoon-Ki; Iruela-Arispe, M Luisa; Rini, James M; van der Kooy, Derek; Friedlander, Martin; Nagy, Andras

    2014-01-01

    Current therapeutic antiangiogenic biologics used for the treatment of pathological ocular angiogenesis could have serious side effects due to their interference with normal blood vessel physiology. Here, we report the generation of novel antivascular endothelial growth factor-A (VEGF) biologics, termed VEGF “Sticky-traps,” with unique properties that allow for local inhibition of angiogenesis without detectable systemic side effects. Using genetic and pharmacological approaches, we demonstrated that Sticky-traps could locally inhibit angiogenesis to at least the same extent as the original VEGF-trap that also gains whole-body access. Sticky-traps did not cause systemic effects, as shown by uncompromised wound healing and normal tracheal vessel density. Moreover, if injected intravitreally, recombinant Sticky-trap remained localized to various regions of the eye, such as the inner-limiting membrane and ciliary body, for prolonged time periods, without gaining access either to the photoreceptors/choriocapillaris area or the circulation. These unique pharmacological characteristics of Sticky-trap could allow for safe treatment of pathological angiogenesis in patients with diabetic retinopathy and retinopathy of pre-maturity. PMID:24705878

  9. Oral Administration of Blueberry Inhibits Angiogenic Tumor Growth and Enhances Survival of Mice with Endothelial Cell Neoplasm

    PubMed Central

    Fang, Huiqing; Khanna, Savita; Harper, Justin; Phillips, Gary; Sen, Chandan K.

    2009-01-01

    Abstract Endothelial cell neoplasms are the most common soft tissue tumor in infants. Subcutaneous injection of spontaneously transformed murine endothelial (EOMA) cells results in development of hemangioendothelioma (HE). We have previously shown that blueberry extract (BBE) treatment of EOMA cells in vitro prior to injection in vivo can significantly inhibit the incidence and size of developing HE. In this study, we sought to determine whether oral BBE could be effective in managing HE and to investigate the mechanisms through which BBE exerts its effects on endothelial cells. A dose-dependent decrease in HE tumor size was observed in mice receiving daily oral gavage feeds of BBE. Kaplan-Meier survival curve showed significantly enhanced survival for mice with HE tumors given BBE, compared to control. BBE treatment of EOMA cells inhibited both c-Jun N-terminal kinase (JNK) and NF-κB signaling pathways that culminate in monocyte chemoattractant protein-1 (MCP-1) expression required for HE development. Antiangiogenic effects of BBE on EOMA cells included decreased proliferation by BrdU assay, decreased sprouting on Matrigel, and decreased transwell migration. Thus, this work provides first evidence demonstrating that BBE can limit tumor formation through antiangiogenic effects and inhibition of JNK and NF-κB signaling pathways. Oral administration of BBE represents a potential therapeutic antiangiogenic strategy for treating endothelial cell neoplasms in children. Antioxid Redox Signal 11, 47–58. PMID:18817478

  10. (-)-Epigallocatechin gallate inhibits TNF-α-induced PAI-1 production in vascular endothelial cells.

    PubMed

    Cao, Yanli; Wang, Difei; Wang, Xiaoli; Zhang, Jin; Shan, Zhongyan; Teng, Weiping

    2013-11-01

    : (-)-Epigallocatechin gallate (EGCG), the major catechin derived from green tea, reduces the incidence of cardiovascular diseases such as atherosclerosis. Plasminogen activator inhibitor-1 (PAI-1) accelerates thrombus formation upon ruptured atherosclerotic plaques. However, it is not known whether or not EGCG inhibits PAI-1 production induced by tumor necrosis factor-α (TNF-α) in endothelial cells. This study tested the hypothesis that EGCG might have an inhibitory effect on PAI-1 production induced by TNF-α. Human umbilical vein endothelial cells were cultured and incubated with TNF-α and/or EGCG. The expression of p-extracellular regulated protein kinases (p-ERK1/2) and tumor necrosis factor receptor (TNFR1) protein was quantified by Western blotting, and PAI-1 levels were measured by enzyme-linked immunosorbent assay. The results showed that TNF-α increased PAI-1 production in both a dose-dependent and time-dependent manner, and EGCG prevented TNF-α-mediated PAI-1 production and reduced phosphorylation of ERK1/2. The ERK1/2 inhibitor, PD98059 (20 μmol/L), downregulated TNF-α-induced PAI-1 expression 57.69 ± 2.46% (P < 0.01), but had no effect in cells pretreated with EGCG. TNF-α stimulation resulted in a significant decrease in TNFR1, an effect that was abolished by pretreatment with EGCG. These results suggest that EGCG could provide vascular benefits in inflammatory cardiovascular diseases such as decreased thrombus formation associated with ruptured atherosclerotic plaques.

  11. HIV inhibits endothelial reverse cholesterol transport through impacting subcellular Caveolin-1 trafficking.

    PubMed

    Lin, Shanshan; Nadeau, Peter E; Mergia, Ayalew

    2015-07-15

    Human immunodeficiency virus (HIV) infection leads to decreased reverse cholesterol transport (RCT) in macrophages, and Nef mediated down-regulation and redistribution of ATP-binding cassette transporter A1 (ABCA1) are identified as key factors for this effect. This may partially explain the increased risk of atherosclerosis in HIV infected individuals. Since endothelial dysfunction is key in the initial stages of atherosclerosis, we sought to determine whether RCT was affected in human aortic endothelial cells (HAECs). We found that apoA-I does not significantly stimulate cholesterol efflux in HAECs while cholesterol efflux to high-density lipoprotein (HDL) was dramatically reduced in HAECs co-cultured with HIV infected cells. Studies with wild type and Nef defective HIV revealed no significant differences suggesting that multiple factors are working perhaps in concert with Nef to affect cholesterol efflux to HDL from HAECs. Interestingly, treating HAECs with recombinant Nef showed similar effect in HDL mediated cholesterol efflux as observed in HAECs co-cultured with HIV infected cells. Using a detergent-free based subcellular fractionation approach, we demonstrated that exposure of HAECs to HIV infected cells or Nef alone disrupts caveolin 1 (Cav-1) subcellular trafficking upon HDL stimulation. Moreover, Nef significantly enhanced tyrosine 14 phosphorylation of Cav-1 which may have an impact on recycling of Cav-1 and caveolae. These results suggest that HIV interferes with cholesterol efflux by HDL in HAECs through the disruption of Cav-1s' cellular distribution and that multiple factors are involved, possibly including Nef, for the inhibition of HDL mediated cholesterol efflux and alteration of cellular distribution of Cav-1.

  12. [Inhibition of alphastatin on angiogenesis in human endothelial cells and the mechanism thereof: an experimental study].

    PubMed

    Chen, Lin; Li, Tao; Li, Rong; Wei, Bo; Duan, Hai-feng; Wang, Hua; Wang, Li-sheng

    2006-04-18

    To explore the effect of alphastatin on angiogenesis activity of human umbilical vein endothelial cells and mechanism thereof. Human umbilical vein endothelial cells of the line ECV304 was cultured. Hepatic growth factor (HGF) and alphastatin of the concentrations of 10, 100, or 1000 nmol/L were use in migration test ECV304 cells at logarithmic stage were inoculated in a 96-well plate. Alphastatin of different concentrations was added, 24, 48, 72, and 96 hours later MTT was added to detect the A(490) nm values with and draw a growth curve. Phorbol 12-myristate 13-acetate (PMA) was used as positive group. The formation of capillary-like structure was examined with fluorescent microscopy. RT-PCR was used to examine the expression of sphingosine kinase (SPK) mRNA in the ECV304 cells. ECV304 cells were treated with alphastatin of 10 nmol/L, 100 nmol/L, or 1000 nmol/L respectively. SPK activity was examined by using [gamma-(32)P] ATP. The number of migrated cells treated with alphastatin of the concentrations of 10, 100, and 1000 nmol/L were (103 +/- 4), (75 +/- 3), and (13 +/- 1) respectively, all significantly lower than that of the HGF group (131 +/- 4, all P < 0.05). The values at different time points of the ECV304 cells treated with alphastatin of different concentrations were not significantly different from that of the HGF group. The area of capillary-like structure of the PMA group was 2996 +/- 31 microm(2)/field, and those of the groups of alphastatin of the concentrations of 100 and 1000 nmol/L were 1509 +/- 30 microm(2)/field and 1301 +/- 20 microm(2)/field respectively, all significantly less than that of the PMA group (2996 +/- 31 microm(2)/field, all P < 0.05). However, there was not a dose-dependent manner in the inhibitive activity of alphastatin on the formation of capillary-like structure. RT-PCR showed that quantity of SPK mRNA product was amplified from the ECV304 cells. The S1P activity of the ECV304 treated with alphastatin was significantly lower

  13. Itraconazole Side Chain Analogues: Structure–Activity Relationship Studies for Inhibition of Endothelial Cell Proliferation, Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) Glycosylation, and Hedgehog Signaling

    PubMed Central

    Shi, Wei; Nacev, Benjamin A.; Aftab, Blake T.; Head, Sarah; Rudin, Charles M.; Liu, Jun O.

    2012-01-01

    Itraconazole is an antifungal drug that was recently found to possess potent antiangiogenic activity and anti-hedgehog (Hh) pathway activity. To search for analogues of itraconazole with greater potency and to understand the structure–activity relationship in both antiangiogenic and Hh targeting activity, 25 itraconazole side chain analogues were synthesized and assayed for inhibition of endothelial cell proliferation and Gli1 transcription in a medulloblastoma (MB) culture. Through this analysis, we have identified analogues with increased potency for inhibiting endothelial cell proliferation and the Hh pathway, as well as VEGFR2 glycosylation that was recently found to be inhibited by itraconazole. An SAR analysis of these activities revealed that potent activity of the analogues against VEGFR2 glycosylation was generally driven by side chains of at least four carbons in composition with branching at the α or β position. SAR trends for targeting the Hh pathway were divergent from those related to HUVEC proliferation or VEGFR2 glycosylation. These results also suggest that modification of the sec-butyl side chain can lead to enhancement of the biological activity of itraconazole. PMID:21936514

  14. Developmental endothelial locus-1 inhibits MIF production through suppression of NF-κB in macrophages.

    PubMed

    Lee, Seung-Hwan; Kim, Dong-Young; Kang, Yoon-Young; Kim, Hyesoon; Jang, Jungin; Lee, Mi-Ni; Oh, Goo Taeg; Kang, Sang-Wook; Choi, Eun Young

    2014-04-01

    Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that regulates leukocyte recruitment, thereby playing a pivotal role in the regulation of innate and adaptive immunity and tumor progression. Elevated levels of MIF are associated with numerous inflammatory disorders and cancers. To determine whether developmental endothelial locus-1 (Del-1) regulated MIF, RAW264.7 macrophages were treated with Del-1 and assessed using ELISA. The results showed that MIF was downregulated in macrophages by Del-1, an endogenous anti-inflammatory protein that was previously shown to limit leukocyte adhesion and migration. Treatment of RAW264.7 macrophages with Del-1 inhibited constitutive and lipopolysaccharide (LPS)-induced MIF secretion. Recombinant Del-1 protein attenuated the phosphorylation of IκBα induced by a relatively low concentration of LPS in THP-1 monocytes, but did not inhibit IκBα phosphorylation in response to a relatively high concentration of LPS. Concomitantly, translocation of NF-κB to the nucleus was inhibited by Del-1 in LPS-activated macrophages. In addition, conditioned medium harvested from cells transfected with a Del-1 expression plasmid suppressed NF-κB activation in response to relatively low concentrations of TNF-α, albeit not the activation that was induced by a relatively high concentration of TNF-α. On the other hand, although Del-1 enhanced the macrophage expression of p53, a known negative regulator of MIF production, MIF production was not significantly affected by the level of p53 in mouse bone marrow-derived macrophages. These findings suggested that Del-1 controls NF-κB-activated MIF production in macrophages, and the potential application of Del-1 to therapeutic modalities for chronic inflammation-associated cancers.

  15. Differential inhibition of oxidized LDL-induced apoptosis in human endothelial cells treated with different flavonoids.

    PubMed

    Jeong, Yu-Jin; Choi, Yean-Jung; Kwon, Hyang-Mi; Kang, Sang-Wook; Park, Hyoung-Sook; Lee, Myungsook; Kang, Young-Hee

    2005-05-01

    High plasma level of cholesterol is a well-known risk factor for atherosclerotic diseases. Oxidized LDL induces cellular and nuclear damage that leads to apoptotic cell death. We tested the hypothesis that flavonoids may function as antioxidants with regard to LDL incubated with 5 microm-Cu(2+) alone or in combination with human umbilical vein endothelial cells (HUVEC). Cytotoxicity and formation of thiobarbituric acid-reactive substances induced by Cu(2+)-oxidized LDL were examined in the presence of various subtypes of flavonoid. Flavanols, flavonols and flavanones at a non-toxic dose of 50 microm markedly inhibited LDL oxidation by inhibiting the formation of peroxidative products. In contrast, the flavones luteolin and apigenin had no such effect, with >30 % of cells killed after exposure to 0.1 mg LDL/ml. Protective flavonoids, especially (-)-epigallocatechin gallate, quercetin, rutin and hesperetin, inhibited HUVEC nuclear condensation and fragmentation induced by Cu(2+)-oxidized LDL. In addition, immunochemical staining and Western blot analysis revealed that anti-apoptotic Bcl-2 expression was enhanced following treatment with these protective flavonoids. However, Bax expression and caspase-3 cleavage stimulated by 18 h incubation with oxidized LDL were reduced following treatment with these protective flavonoids. The down-regulation of Bcl-2 and up-regulation of caspase-3 activation were reversed by the cytoprotective flavonoids, (-)-epigallocatechin gallate, quercetin and hesperetin, at >/=10 microm. These results suggest that flavonoids may differentially prevent Cu(2+)-oxidized LDL-induced apoptosis and promote cell survival as potent antioxidants. Survival potentials of certain flavonoids against cytotoxic oxidized LDL appeared to stem from their disparate chemical structure. Furthermore, dietary flavonoids may have therapeutic potential for protecting the endothelium from oxidative stress and oxidized LDL-triggered atherogenesis.

  16. Dehydroepiandrosterone inhibits the TNF-alpha-induced inflammatory response in human umbilical vein endothelial cells.

    PubMed

    Gutiérrez, Gisela; Mendoza, Criselda; Zapata, Estrella; Montiel, Angélica; Reyes, Elba; Montaño, Luis Felipe; López-Marure, Rebeca

    2007-01-01

    Dehydroepiandrosterone (DHEA) has a protective role against atherosclerosis. We determined the effect of pharmacological doses of DHEA upon the adhesion of monocytic U937 cells to human umbilical vein endothelial cells (HUVEC), as well as the expression of adhesion and chemoattractant molecules, the translocation of NF-kappaB, the degradation of IkappaB-alpha and the production of reactive oxygen species (ROS) in HUVEC. Adhesion of U937 cells to DHEA-treated HUVEC was evaluated by co-culture experiments using [(3)H]-thymidine-labeled U937 cells. The expression of adhesion and chemoattractant molecules was evaluated by flow cytometry and RT-PCR, respectively; NF-kappaB translocation was determined by Electrophoretic Mobility Shift Assay (EMSA) and IkappaB-alpha degradation by Western blot. ROS production was determined by the reduction of fluorescent DCFDA. TNF-alpha was used to induce inflammatory responses in HUVEC. One hundred micromolar of DHEA-treatment inhibited the TNF-alpha-induced expression of ICAM-1, E-selectin, ROS production and U937 cells adhesion to HUVEC, and interfered with NF-kappaB translocation and IkappaB-alpha degradation. DHEA at the above mention concentration also inhibited the mRNA expression of MCP-1 and IL-8 in basal conditions but not in TNF-alpha-stimulated conditions. Our results suggest that DHEA inhibits the expression of molecules involved in the inflammatory process, therefore it could be used as an alternative in the treatment of chronic inflammatory diseases such as atherosclerosis.

  17. Asymmetric dimethylarginine does not inhibit arginase activity and is pro-proliferative in pulmonary endothelial cells.

    PubMed

    Chen, Bernadette; Strauch, Krista; Jin, Yi; Cui, Hongmei; Nelin, Leif D; Chicoine, Louis G

    2014-07-01

    Asymmetric dimethylarginine (ADMA) is an endogenously produced nitric oxide synthase (NOS) inhibitor. L-Arginine can be metabolised by NOS and arginase, and arginase is the first step in polyamine production necessary for cellular proliferation. We tested the hypothesis that ADMA would inhibit NOS but not arginase activity and that this pattern of inhibition would result in greater L-arginine bioavailability to arginase, thereby increasing viable cell number. Bovine arginase was used in in vitro activity assays with various concentrations of substrate (L-arginine, ADMA, N(G) -monomethyl-L-arginine (L-NMMA) and N(G) -nitro-L-arginine methyl ester (L-NAME)). Only L-arginine resulted in measurable urea production (Km = 6.9 ± 0.8 mmol/L; Vmax = 6.6 ± 0.3 μmol/mg protein per min). We then incubated bovine arginase with increasing concentrations of ADMA, L-NMMA and L-NAME in the presence of 1 mmol/L l-arginine and found no effect of any of the tested compounds on arginase activity. Using bovine pulmonary arterial endothelial cells (bPAEC) we determined the effects of ADMA on nitric oxide (NO) and urea production and found significantly lower NO production and greater urea production (P < 0.003) with ADMA, without changes in arginase protein levels. In addition, ADMA treatment resulted in an approximately 30% greater number of viable cells after 48 h than in control bPAEC. These results demonstrate that ADMA is neither a substrate nor an inhibitor of arginase activity and that in bPAEC ADMA inhibits NO production and enhances urea production, leading to more viable cells. These results may have pathophysiological implications in disorders associated with higher ADMA levels, such as pulmonary hypertension.

  18. Vascular incorporation of alpha-tocopherol prevents endothelial dysfunction due to oxidized LDL by inhibiting protein kinase C stimulation.

    PubMed Central

    Keaney, J F; Guo, Y; Cunningham, D; Shwaery, G T; Xu, A; Vita, J A

    1996-01-01

    Excess vascular oxidative stress has been linked to impaired endothelium-dependent arterial relaxation in hypercholesterolemia. alpha-Tocopherol (AT) preserves endothelial function in hypercholesterolemia although the mechanism(s) for this protective effect is (are) not known. We examined the tissue-specific effects of AT on oxidized LDL (ox-LDL)-mediated endothelial dysfunction in male New Zealand White rabbits. Animals consumed chow deficient in (< 10 IU/kg) or supplemented with (1,000 IU/kg) AT for 28 d. Exposure of thoracic aortae from AT-deficient animals to ox-LDL (0-500 microg/ml) for 4 h produced dose-dependent inhibition of acetylcholine-mediated relaxation (P < 0.05) while vessels derived from animals consuming AT were resistant to ox-LDL-mediated endothelial dysfunction. Animals consuming AT demonstrated a 100-fold increase in vascular AT content and this was strongly correlated with vessel resistance to endothelial dysfunction from ox-LDL (R = 0.67; P = 0.0014). These results were not explained by an effect of AT on ox-LDL-mediated cytotoxicity by LDH assay or scanning electron microscopy. Vascular incorporation of AT did produce resistance to endothelial dysfunction from protein kinase C stimulation, an event that has been implicated in the vascular response to ox-LDL. Human aortic endothelial cells loaded with AT also demonstrated resistance to protein kinase C stimulation by both phorbol ester and ox-LDL. Thus, these data indicate that enrichment of vascular tissue with AT protects the vascular endothelium from ox-LDL-mediated dysfunction, at least in part, through the inhibition of protein kinase C stimulation. These findings suggest one potential mechanism for the observed beneficial effect of AT in preventing the clinical expression of coronary artery disease that is distinct from the antioxidant protection of LDL. PMID:8755649

  19. Inhibition of cultured bovine aortic endothelial cell proliferation by sodium spirulan, a new sulfated polysaccharide isolated from Spirulina platensis.

    PubMed

    Kaji, Toshiyuki; Fujiwara, Yasuyuki; Hamada, Chieko; Yamamoto, Chika; Shimada, Satomi; Lee, Jung-Bum; Hayashi, Toshimitsu

    2002-06-01

    Sodium spirulan (Na-SP) is a sulfated polysaccharide isolated from the blue-green alga Spirulina platensis, which consists of two types of disaccharide repeating units, O-hexuronosyl-rhamnose (aldobiuronic acid) and O-rhamnosyl-3-O-methylrhamnose (acofriose) with sulfate groups, other minor saccharides and sodium ion. Vascular endothelial cells are present on the inner surface of blood vessels in a monolayer and have anticoagulant properties. To address the question whether Na-SP influences the maintenance of endothelial cell monolayers, we investigated the proliferation of cultured bovine aortic endothelial cells treated with Na-SP. It was found that Na-SP has an inhibitory activity on endothelial cell proliferation accompanied with suppression of whole protein synthesis but without non-specific cell damage. The inhibitory activity of Na-SP was the strongest when compared to that of heparan sulfate, heparin, dextran sulfate, dermatan sulfate, chondroitin sulfate A/C and hyaluronan. Furthermore, it was shown that the inhibitory activity of Na-SP disappeared by either desulfation or depolymerization. The present data suggest that Na-SP is a unique sulfated polysaccharide that strongly inhibits vascular endothelial cell proliferation, and the inhibitory activity requires polymerization of sulfated O-rhamnosyl-acofriose repeating units.

  20. Endoglin inhibits ERK-induced c-Myc and cyclin D1 expression to impede endothelial cell proliferation

    SciTech Connect

    Pan, Christopher C.; Bloodworth, Jeffrey C.; Mythreye, Karthikeyan; Lee, Nam Y.

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer Endoglin inhibits ERK activation in endothelial cells. Black-Right-Pointing-Pointer Endoglin is a regulator of c-Myc and cyclin D1 expression. Black-Right-Pointing-Pointer {beta}-arrestin2 interaction with endoglin is required for ERK/c-Myc repression. Black-Right-Pointing-Pointer Endoglin impedes cellular proliferation by targeting ERK-induced mitogenic signaling. -- Abstract: Endoglin is an endothelial-specific transforming growth factor beta (TGF-{beta}) co-receptor essential for angiogenesis and vascular remodeling. Endoglin regulates a wide range of cellular processes, including cell adhesion, migration, and proliferation, through TGF-{beta} signaling to canonical Smad and Smad-independent pathways. Despite its overall pro-angiogenic role in the vasculature, the underlying mechanism of endoglin action is poorly characterized. We previously identified {beta}-arrestin2 as a binding partner that causes endoglin internalization from the plasma membrane and inhibits ERK signaling towards endothelial migration. In the present study, we examined the mechanistic role of endoglin and {beta}-arrestin2 in endothelial cell proliferation. We show that endoglin impedes cell growth through sustained inhibition of ERK-induced c-Myc and cyclin D1 expression in a TGF-{beta}-independent manner. The down-regulation of c-Myc and cyclin D1, along with growth-inhibition, are reversed when the endoglin/{beta}-arrestin2 interaction is disrupted. Given that TGF-{beta}-induced Smad signaling potently represses c-Myc in most cell types, our findings here show a novel mechanism by which endoglin augments growth-inhibition by targeting ERK and key downstream mitogenic substrates.

  1. The Heme Metabolite Carbon Monoxide Facilitates KSHV Infection by Inhibiting TLR4 Signaling in Endothelial Cells.

    PubMed

    Botto, Sara; Gustin, Jean K; Moses, Ashlee V

    2017-01-01

    Kaposi sarcoma herpesvirus (KSHV) is the etiologic agent of Kaposi sarcoma (KS) and certain rare B cell lymphoproliferative disorders. KSHV infection of endothelial cells (EC) in vitro increases expression of the inducible host-encoded enzyme heme oxygenase-1 (HO-1), which is also strongly expressed in KS tumors. HO-1 catalyzes the rate-limiting step in the conversion of heme into iron, biliverdin and the gasotransmitter carbon monoxide (CO), all of which share anti-apoptotic, anti-inflammatory, pro-survival, and tumorigenic activities. Our previous work has shown that HO-1 expression in KSHV-infected EC is characterized by a rapid yet transient induction at early times post-infection, followed by a sustained upregulation co-incident with establishment of viral latency. These two phases of expression are independently regulated, suggesting distinct roles for HO-1 in the virus life cycle. Here, we investigated the role of HO-1 during acute infection, prior to the onset of viral gene expression. The early infection phase involves a series of events that culminate in delivery of the viral genome to the nucleus. Primary infection also leads to activation of host innate immune effectors, including the pattern recognition receptor TLR4, to induce an antiviral response. It has been shown that TLR4-deficient EC are more susceptible to KSHV infection than wild-type controls, suggesting an important inhibitory role for TLR4 in the KSHV life cycle. TLR4 signaling is in turn subject to regulation by several virus-encoded immune evasion factors. In this report we identify HO-1 as a host protein co-opted by KSHV as part of a rapid immune evasion strategy. Specifically, we show that early HO-1 induction by KSHV results in increased levels of endogenous CO, which functions as a TLR4 signaling inhibitor. In addition, we show that CO-mediated inhibition of TLR4 signaling leads to reduced expression of TLR4-induced antiviral genes, thus dampening the host antiviral response and

  2. Multi-ligand poly(L-lactic-co-glycolic acid) nanoparticles inhibit activation of endothelial cells.

    PubMed

    Xu, Hao; Kona, Soujanya; Su, Lee-Chun; Tsai, Yi-Ting; Dong, Jing-Fei; Brilakis, Emmanouil S; Tang, Liping; Banerjee, Subhash; Nguyen, Kytai T

    2013-08-01

    Endothelial cell (EC) activation and inflammation is a key step in the initiation and progression of many cardiovascular diseases. Targeted delivery of therapeutic reagents to inflamed EC using nanoparticles is challenging as nanoparticles do not arrest on EC efficiently under high shear stress. In this study, we developed a novel polymeric platelet-mimicking nanoparticle for strong particle adhesion onto ECs and enhanced particle internalization by ECs. This nanoparticle was encapsulated with dexamethasone as the anti-inflammatory drug, and conjugated with polyethylene glycol, glycoprotein 1b, and trans-activating transcriptional peptide. The multi-ligand nanoparticle showed significantly greater adhesion on P-selectin, von Willebrand Factor, than the unmodified particles, and activated EC in vitro under both static and flow conditions. Treatment of injured rat carotid arteries with these multi-ligand nanoparticles suppressed neointimal stenosis more than unconjugated nanoparticles did. These results indicate that this novel multi-ligand nanoparticle is efficient to target inflamed EC and inhibit inflammation and subsequent stenosis.

  3. The Traditional Japanese Formula Keishibukuryogan Inhibits the Production of Inflammatory Cytokines by Dermal Endothelial Cells

    PubMed Central

    Yoshihisa, Yoko; Furuichi, Megumi; Ur Rehman, Mati; Ueda, Chieko; Makino, Teruhiko; Shimizu, Tadamichi

    2010-01-01

    Keishibukuryogan (KBG) is one of the traditional herbal formulations widely administered to patients with blood stagnation for improving blood circulation; currently, it is the most frequently prescribed medicine in Japan. KBG has been reported to improve conjunctional microcirculation. The aim of this study was to evaluate the role of KBG and paeoniflorin, a bioactive compound of KBG, in inhibiting the production of inflammatory cytokines using human dermal microvessel endothelial cells (HDMECs). The authors observed that lipopolysaccharide (LPS; 1 μg/mL) stimulated the secretion of proinflammatory cytokines in HDMECs. KBG treatment (10 mg/mL) significantly suppressed the mRNA levels of migration inhibitory factor (MIF), interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α in LPS-stimulated cultured HDMECs. Similarly, paeoniflorin significantly suppressed the mRNA levels of these cytokines in LPS-stimulated cultured HDMECs. ELISA showed that KBG and paeoniflorin suppressed the production of MIF, IL-6, IL-8, and TNF-α in LPS-stimulated HDMECs. Moreover, KBG and paeoniflorin decreased the expression of cyclooxygenase-2 and inducible nitric oxide synthase (iNOS) in these cells. These results suggest that KBG may be useful for improving microvascular inflammation in patients with skin diseases. PMID:21253500

  4. Effects of Vascular Endothelial Growth Factor Signaling Inhibition on Human Erythropoiesis

    PubMed Central

    Bhatta, Sumita S.; Wroblewski, Kristen E.; Agarwal, Kelly L.; Sit, Laura; Cohen, Ezra E.W.; Seiwert, Tanguy Y.; Karrison, Theodore; Bakris, George L.; Ratain, Mark J.; Vokes, Everett E.

    2013-01-01

    Inhibition of vascular endothelial growth factor (VEGF) signaling increases red blood cell (RBC) counts, and erythropoiesis markers have been proposed to guide antiangiogenic therapy in humans. We analyzed RBC measurements in patients enrolled in three studies: a phase II trial of axitinib in thyroid cancer; a study of sorafenib in advanced solid tumors; and a randomized trial of fluorouracil, hydroxyurea, and radiation with and without bevacizumab for head and neck cancer. In the sorafenib trial, plasma erythropoietin concentrations were measured at baseline, day 8, and day 35. Over the first 84 days of treatment, RBC counts increased for each day on sorafenib (2.7 M/μL [95% confidence interval (CI), 1.5–3.9]) and axitinib (4.3 M/μL [95% CI, 2.2–6.5]). RBCs declined over the first 68 days of cytotoxic chemoradiotherapy alone (−12.8 M/μL per day [95% CI, −15.7 to −9.8]) but less so with added bevacizumab (−7.2 M/μL per day [95% CI, −9.5 to −4.9]). Erythropoietin levels increased, on average, by 9.5 mIU/mL between day 8 and day 35 of sorafenib exposure. No significant relationships between elevations in RBCs and changes in volume status or blood pressure or between elevations in erythropoietin and smoking status were found. VEGF signaling inhibition is associated with increased RBC and erythropoietin production in humans. The effects of these changes are subtle at physiologic doses and are unlikely to be clinically useful biomarkers for guiding the administration of or predicting treatment responses to VEGF pathway inhibitors. PMID:23900000

  5. Effects of vascular endothelial growth factor signaling inhibition on human erythropoiesis.

    PubMed

    Bhatta, Sumita S; Wroblewski, Kristen E; Agarwal, Kelly L; Sit, Laura; Cohen, Ezra E W; Seiwert, Tanguy Y; Karrison, Theodore; Bakris, George L; Ratain, Mark J; Vokes, Everett E; Maitland, Michael L

    2013-01-01

    Inhibition of vascular endothelial growth factor (VEGF) signaling increases red blood cell (RBC) counts, and erythropoiesis markers have been proposed to guide antiangiogenic therapy in humans. We analyzed RBC measurements in patients enrolled in three studies: a phase II trial of axitinib in thyroid cancer; a study of sorafenib in advanced solid tumors; and a randomized trial of fluorouracil, hydroxyurea, and radiation with and without bevacizumab for head and neck cancer. In the sorafenib trial, plasma erythropoietin concentrations were measured at baseline, day 8, and day 35. Over the first 84 days of treatment, RBC counts increased for each day on sorafenib (2.7 M/μL [95% confidence interval (CI), 1.5-3.9]) and axitinib (4.3 M/μL [95% CI, 2.2-6.5]). RBCs declined over the first 68 days of cytotoxic chemoradiotherapy alone (-12.8 M/μL per day [95% CI, -15.7 to -9.8]) but less so with added bevacizumab (-7.2 M/μL per day [95% CI, -9.5 to -4.9]). Erythropoietin levels increased, on average, by 9.5 mIU/mL between day 8 and day 35 of sorafenib exposure. No significant relationships between elevations in RBCs and changes in volume status or blood pressure or between elevations in erythropoietin and smoking status were found. VEGF signaling inhibition is associated with increased RBC and erythropoietin production in humans. The effects of these changes are subtle at physiologic doses and are unlikely to be clinically useful biomarkers for guiding the administration of or predicting treatment responses to VEGF pathway inhibitors.

  6. The Biflavonoid Amentoflavone Inhibits Neovascularization Preventing the Activity of Proangiogenic Vascular Endothelial Growth Factors*

    PubMed Central

    Tarallo, Valeria; Lepore, Laura; Marcellini, Marcella; Dal Piaz, Fabrizio; Tudisco, Laura; Ponticelli, Salvatore; Lund, Frederik Wendelboe; Roepstorff, Peter; Orlandi, Augusto; Pisano, Claudio; De Tommasi, Nunziatina; De Falco, Sandro

    2011-01-01

    The proangiogenic members of VEGF family and related receptors play a central role in the modulation of pathological angiogenesis. Recent insights indicate that, due to the strict biochemical and functional relationship between VEGFs and related receptors, the development of a new generation of agents able to target contemporarily more than one member of VEGFs might amplify the antiangiogenic response representing an advantage in term of therapeutic outcome. To identify molecules that are able to prevent the interaction of VEGFs with related receptors, we have screened small molecule collections consisting of >100 plant extracts. Here, we report the isolation and identification from an extract of the Malian plant Chrozophora senegalensis of the biflavonoid amentoflavone as an antiangiogenic bioactive molecule. Amentoflavone can to bind VEGFs preventing the interaction and phosphorylation of VEGF receptor 1 and 2 (VEGFR-1,VEGFR-2) and to inhibit endothelial cell migration and capillary-like tube formation induced by VEGF-A or placental growth factor 1 (PlGF-1) at low μm concentration. In vivo, amentoflavone is able to inhibit VEGF-A-induced chorioallantoic membrane neovascularization as well as tumor growth and associated neovascularization, as assessed in orthotropic melanoma and xenograft colon carcinoma models. In addition structural studies performed on the amentoflavone·PlGF-1 complex have provided evidence that this biflavonoid effectively interacts with the growth factor area crucial for VEGFR-1 receptor recognition. In conclusion, our results demonstrate that amentoflavone represents an interesting new antiangiogenic molecule that is able to prevent the activity of proangiogenic VEGF family members and that the biflavonoid structure is a new chemical scaffold to develop powerful new antiangiogenic molecules. PMID:21471210

  7. Flavonoids inhibit hypoxia-induced vascular endothelial growth factor expression by a HIF-1 independent mechanism.

    PubMed

    Ansó, Elena; Zuazo, Alicia; Irigoyen, Marta; Urdaci, María C; Rouzaut, Ana; Martínez-Irujo, Juan J

    2010-06-01

    Flavonoids are a group of polyphenolic dietary compounds that have been proposed to possess chemopreventive properties against lung cancer. In this work we analyzed the effect of a group of 20 structurally related flavonoids, including flavones, flavonols and isoflavones, on the production of vascular endothelial growth factor (VEGF) induced by hypoxia in NCI-H157 cells. VEGF is the main regulator of physiological and pathological angiogenesis and is highly stimulated by hypoxia-inducible factor 1 (HIF-1). We found that apigenin, luteolin, fisetin and quercetin inhibited hypoxia-induced VEGF expression in the low micromolar range. Structure-activity relationships demonstrated that flavone derivatives were the most active compounds and that hydroxylation of the A ring at the positions 5 and 7 and of the B ring at the 4' position were important for this activity. Interestingly, only a group of VEGF inhibitors, including apigenin, flavone and 4',7-dihydroxiflavone, reduced the expression of HIF-1alpha under these conditions, whereas others, such as fisetin, luteolin, galangin or quercetin, induced HIF-1alpha expression while reducing those of VEGF. When cells were exposed to hypoxia in the presence of these flavonoids, HIF-1alpha translocated to the nucleus and interacted with p300/CBP, but this complex was transcriptionally inactive. Taken together these findings indicate that flavonoids impair VEGF transcription by an alternative mechanism that did not depend on nuclear HIF levels. We also found that flavonoids suppressed hypoxia-induced STAT3 tyrosine phosphorylation and that this activity correlated with their potency as VEGF inhibitors, suggesting that inhibition of STAT3 function may play a role in this process.

  8. Ceramide mediates inhibition of the Akt/eNOS pathway by high levels of glucose in human vascular endothelial cells.

    PubMed

    Wang, Aimin; Li, Chun; Liao, Jie; Dong, Min; Xiao, Zhiming; Lei, Minxiang

    2013-01-01

    To investigate how ceramide mediates the effects of high-glucose-induced inhibition of the Akt/endothelial nitric oxide synthase (eNOS) signalling pathway in human vascular endothelial cells (HUVECs). NO levels were determined by ELISA. Endogenous ceramide levels were determined using a liquid chromatography-mass spectrometry assay. Akt and eNOS protein expressions were determined by Western blotting. High-glucose levels induce ceramide accumulation in a dose- and time-dependent manner (p<0.05). We also show that exposure of HUVECs to high-glucose conditions inhibits the insulin-mediated activation of Akt/eNOS signalling and the subsequent NO generation in a dose-dependent manner (p<0.05). Preventing de novo ceramide synthesis attenuated the antagonistic effects of high-glucose levels on the Akt/eNOS signalling pathway (p<0.05); conversely, inducing ceramide build-up augmented the inhibitory effects of high-glucose levels on the Akt/eNOS signalling pathway (p<0.05). Ceramide is both necessary and sufficient for mediating the inhibition of the Akt/eNOS signalling pathway by high-glucose levels in endothelial cells.

  9. Propranolol inhibits angiogenesis via down-regulating the expression of vascular endothelial growth factor in hemangioma derived stem cell

    PubMed Central

    Zhang, Ling; Mai, Hua-Ming; Zheng, Jing; Zheng, Jia-Wei; Wang, Yan-An; Qin, Zhong-Ping; Li, Ke-Lei

    2014-01-01

    Background: Oral propranolol (PRN) has recently been shown to be highly effective for infantile hemangiomas (IHs), and is currently recommended as the first-line treatment of complicated IHs. However, the therapeutic mechanism(s) still remain unclear. Methods: In this study, we tested hemangioma-derived stem cells for expression of vascular endothelial growth factor (VEGF) in vitro and studied the inhibition of VEGF expression. We used PCR, Elisa, Western blotting and immunohistochemistry in vivo and in vitro trial. Results: The study demonstrated that application of PRN at a “normal” concentration equivalent to plasma concentration did not inhibit proliferation or promote apoptosis of hemangioma derived stem cells (HemSCs) isolated from IH patients. PRN suppressed expression of vascular endothelial growth factor (VEGF) and basic Fibroblast Growth Factor (bFGF) in HemSCs in vitro. Morphological, histological and immunohistological improvement were observed in vivo using murine IH model in which HemSCs pre-treated with PRN were implanted into BALB/c-nu mice. In the pre-treated HemSC grafts, mean micro-vessel density (MVD) significantly decreased and protein levels of VEGF markedly decreased, while bFGF was still detectable. Conclusions: The results suggested PRN inhibited angiogenesis via down-regulating the expression of vascular endothelial growth factor in hemangioma derived stem cell. These findings provide critical insight into the potential mechanisms of PRN action on IH. PMID:24427325

  10. BRN-103, a novel nicotinamide derivative, inhibits VEGF-induced angiogenesis and proliferation in human umbilical vein endothelial cells.

    PubMed

    Choi, Hye-Eun; Yoo, Min-Sang; Choi, Jung-Hye; Lee, Jae Yeol; Kim, Je Hak; Kim, Ji Han; Lee, Joon Kwang; Kim, Gyu Il; Park, Yong; Chi, Yong Ha; Paik, Soo Heui; Lee, Joo Han; Lee, Kyung-Tae

    2011-11-01

    Anti-angiogenesis is regarded as an effective strategy for cancer treatment, and vascular endothelial growth factor (VEGF) plays a key role in the regulations of angiogenesis and vasculogenesis. In the present study, the authors synthesized five novel nicotinamide derivatives which structurally mimic the receptor tyrosine kinase inhibitor sunitinib and evaluated their anti-angiogenic effects. Transwell migration assays revealed that 2-(1-benzylpiperidin-4-yl) amino-N-(3-chlorophenyl) nicotinamide (BRN-103), among the five derivatives most potently inhibited VEGF-induced human umbilical vein endothelial cells (HUVECs). In addition, BRN-103 dose-dependently inhibited VEGF-induced migration, proliferation, and capillary-like tube formation of HUVECs and vessel sprouting from mouse aortic rings. To understand the molecular mechanisms responsible for these activities, the authors examined the effect of BRN-103 on VEGF signaling pathways in HUVECs. BRN-103 was found to suppress the VEGF-induced phosphorylation of VEGF receptor 2 (VEGR2) and the activations of AKT and eNOS. Taken together, these results suggest that BRN-103 inhibits VEGF-mediated angiogenesis signaling in human endothelial cells.

  11. Gold Nanoparticles Inhibit VEGF165-Induced Migration and Tube Formation of Endothelial Cells via the Akt Pathway

    PubMed Central

    Pan, Yunlong; Wu, Qing; Qin, Li; Cai, Jiye; Du, Bin

    2014-01-01

    The early stages of angiogenesis can be divided into three steps: endothelial cell proliferation, migration, and tube formation. Vascular endothelial growth factor (VEGF) is considered the most important proangiogenic factor; in particular, VEGF165 plays a critical role in angiogenesis. Here, we evaluated whether gold nanoparticles (AuNPs) could inhibit the VEGF165-induced human umbilical vein endothelial cell (HUVEC) migration and tube formation. AuNPs and VEGF165 were coincubated overnight at 4°C, after which the effects on cell migration and tube formation were assessed. Cell migration was assessed using a modified wound-healing assay and a transwell chamber assay; tube formation was assessed using a capillary-like tube formation assay and a chick chorioallantoic membrane (CAM) assay. We additionally detected the cell surface morphology and ultrastructure using atomic force microscopy (AFM). Furthermore, Akt phosphorylation downstream of VEGFR-2/PI3K in HUVECs was determined in a Western blot analysis. Our study demonstrated that AuNPs significantly inhibited VEGF165-induced HUVEC migration and tube formation by affecting the cell surface ultrastructure, cytoskeleton and might have inhibited angiogenesis via the Akt pathway. PMID:24987682

  12. Widdrol, a sesquiterpene isolated from Juniperus chinensis, inhibits angiogenesis by targeting vascular endothelial growth factor receptor 2 signaling.

    PubMed

    Jin, Soojung; Yun, Hee Jung; Jeong, Hyun Young; Oh, You Na; Park, Hyun-Jin; Yun, Seung-Geun; Kim, Byung Woo; Kwon, Hyun Ju

    2015-09-01

    Widdrol is an odorous compound derived from Juniperus chinensis that is widely used in traditional medicine to treat fever, inflammation and cancer. It was previously reported that widdrol has antitumor activity by apoptosis induction in cancer cells in vitro. However, its anti-angiogenic activity remains elusive. In the present study, we investigated the anti‑angiogenic activity of widdrol and the molecular mechanisms involved. Widdrol inhibited cell proliferation via G1 phase arrest induction in human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. Additionally, it was associated with a decreased expression of cyclin-dependent kinase 2 (CDK2) and an increased expression of p21, a CDK inhibitor. Widdrol significantly inhibited the cell migration and tube formation of HUVECs using an in vitro angiogenesis assay. The results showed that widdrol suppressed phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream proteins, such as AKT, focal adhesion kinase (FAK) and endothelial nitric oxide synthase (eNOS). Moreover, widdrol effectively reduced tumor growth and blood vessel formation in colon tumor xenograft mice. Collectively, these results suggested that widdrol may act as a potential anti-angiogenic agent by inhibiting vessel sprouting and growth, which may have implications for angioprevention.

  13. HDAC6 inhibition prevents TNF-α-induced caspase 3 activation in lung endothelial cell and maintains cell-cell junctions

    PubMed Central

    Yu, Jinyan; Ma, Mengshi; Ma, Zhongsen; Fu, Jian

    2016-01-01

    Pro-inflammatory mediators such as TNF-α induce caspase activation in endothelial cells, which leads to degradation of cellular proteins, induction of apoptotic signaling, and endothelial cell dysfunction. New therapeutic agents that can inhibit caspase activation may provide protection against inflammatory injury to endothelial cells. In the present study, we examined the effects of selective histone deacetylase 6 (HDAC6) inhibition on TNF-α induced caspase 3 activation and cell-cell junction dysfunction in lung endothelial cells. We also assessed the protective effects of HDAC6 inhibition against lung inflammatory injury in a mouse model of endotoxemia. We demonstrated that selective HDAC6 inhibition or knockdown of HDAC6 expression was able to prevent caspase 3 activation in lung endothelial cells and maintain lung endothelial cell-cell junctions. Mice pre-treated with HDAC6 inhibitors exhibited decreased endotoxin-induced caspase 3 activation and reduced lung vascular injury as indicated by the retention of cell-cell junction protein VE-Cadherin level and alleviated lung edema. Collectively, our data suggest that HDAC6 inhibition is a potent therapeutic strategy against inflammatory injury to endothelial cells. PMID:27419634

  14. Resveratrol protects vascular endothelial cells from high glucose-induced apoptosis through inhibition of NADPH oxidase activation-driven oxidative stress.

    PubMed

    Chen, Feng; Qian, Li-Hua; Deng, Bo; Liu, Zhi-Min; Zhao, Ying; Le, Ying-Ying

    2013-09-01

    Hyperglycemia-induced oxidative stress has been implicated in diabetic vascular complications in which NADPH oxidase is a major source of reactive oxygen species (ROS) generation. Resveratrol is a naturally occurring polyphenol, which has vasoprotective effects in diabetic animal models and inhibits high glucose (HG)-induced oxidative stress in endothelial cells. We aimed to examine whether HG-induced NADPH oxidase activation and ROS production contribute to glucotoxicity to endothelial cells and the effect of resveratrol on glucotoxicity. Using a murine brain microvascular endothelial cell line bEnd3, we found that NADPH oxidase inhibitor (apocynin) and resveratrol both inhibited HG-induced endothelial cell apoptosis. HG-induced elevation of NADPH oxidase activity and production of ROS were inhibited by apocynin, suggesting that HG induces endothelial cell apoptosis through NADPH oxidase-mediated ROS production. Mechanistic studies revealed that HG upregulated NADPH oxidase subunit Nox1 but not Nox2, Nox4, and p22(phox) expression through NF-κB activation, which resulted in elevation of NADPH oxidase activity and consequent ROS production. Resveratrol prevented HG-induced endothelial cell apoptosis through inhibiting HG-induced NF-κB activation, NADPH oxidase activity elevation, and ROS production. HG induces endothelial cell apoptosis through NF-κB/NADPH oxidase/ROS pathway, which was inhibited by resveratrol. Our findings provide new potential therapeutic targets against brain vascular complications of diabetes. © 2013 John Wiley & Sons Ltd.

  15. Rutin Prevents High Glucose-Induced Renal Glomerular Endothelial Hyperpermeability by Inhibiting the ROS/Rhoa/ROCK Signaling Pathway.

    PubMed

    Wang, Xiaoming; Zhao, Xiaohong; Feng, Ting; Jin, Gang; Li, Zhenjiang

    2016-09-01

    Diabetic nephropathy is a progressive kidney disease caused by damage to the capillaries in the glomeruli. Endothelial dysfunction is an early sign of diabetic cardiovascular disease and may contribute to progressive diabetic nephropathy. Hyperglycemia-induced endothelial hyperpermeability is crucial to diabetic nephropathy. Rutin has beneficial effects on diabetic nephropathy, but the exact mechanisms of its protective effect remain elusive. The aim of this study was to assess the role of pretreatment with rutin in an in vitro model of hyperglycemia-induced barrier dysfunction in human renal glomerular endothelial cells. Human renal glomerular endothelial cells were exposed to rutin and/or hyperglycemia for 24 h. Hyperglycemia increased permeability and decreased the junction protein occludin in the cell-cell junction area and the total expression in human renal glomerular endothelial cells, whereas rutin treatment significantly corrected these abnormalities. Furthermore, hyperglycemia-induced activation of RhoA/ROCK was reversed by treatment with rutin or the knockdown of ROCK2. Interestingly, rutin prevented hyperglycemia-induced hyperpermeability, and dysfunction of the tight junction, a high level of reactive oxygen species, and activation of RhoA/ROCK were significantly abolished with the knockdown of Nrf2. In conclusion, rutin significantly prevented hyperglycemia-disrupted renal endothelial barrier function by inhibiting the RhoA/ROCK signaling pathway through decreasing reactive oxygen species, which was mediated by the activation of Nrf2. Our results may explain, at least in part, some beneficial effects of rutin that may be applicable to the treatment of vascular disorders in diabetic nephropathy.

  16. Endothelial Myocyte Enhancer Factor 2c Inhibits Migration of Smooth Muscle Cells Through Fenestrations in the Internal Elastic Lamina.

    PubMed

    Lu, Yao Wei; Lowery, Anthony M; Sun, Li-Yan; Singer, Harold A; Dai, Guohao; Adam, Alejandro P; Vincent, Peter A; Schwarz, John J

    2017-07-01

    Laminar flow activates myocyte enhancer factor 2 (MEF2) transcription factors in vitro to induce expression of atheroprotective genes in the endothelium. Here we sought to establish the role of Mef2c in the vascular endothelium in vivo. To study endothelial Mef2c, we generated endothelial-specific deletion of Mef2c using Tie2-Cre or Cdh5-Cre-ER(T2) and examined aortas and carotid arteries by en face immunofluorescence. We observed enhanced actin stress fiber formation in the Mef2c-deleted thoracic aortic endothelium (laminar flow region), similar to those observed in normal aortic inner curvature (disturbed flow region). Furthermore, Mef2c deletion resulted in the de novo formation of subendothelial intimal cells expressing markers of differentiated smooth muscle in the thoracic aortas and carotids. Lineage tracing showed that these cells were not of endothelial origin. To define early events in intimal development, we induced endothelial deletion of Mef2c and examined aortas at 4 and 12 weeks postinduction. The number of intimal cell clusters increased from 4 to 12 weeks, but the number of cells within a cluster peaked at 2 cells in both cases, suggesting ongoing migration but minimal proliferation. Moreover, we identified cells extending from the media through fenestrations in the internal elastic lamina into the intima, indicating transfenestral smooth muscle migration. Similar transfenestral migration was observed in wild-type carotid arteries ligated to induce neointimal formation. These results indicate that endothelial Mef2c regulates the endothelial actin cytoskeleton and inhibits smooth muscle cell migration into the intima. © 2017 American Heart Association, Inc.

  17. A BMP7 Variant Inhibits Tumor Angiogenesis In Vitro and In Vivo through Direct Modulation of Endothelial Cell Biology

    PubMed Central

    Pallini, Roberto; Vakana, Eliza; Wyss, Lisa; Blosser, Wayne; Ricci-Vitiani, Lucia; D’Alessandris, Quintino Giorgio; Morgante, Liliana; Giannetti, Stefano; Maria Larocca, Luigi; Todaro, Matilde; Benfante, Antonina; Colorito, Maria Luisa; Stassi, Giorgio; De Maria, Ruggero; Rowlinson, Scott; Stancato, Louis

    2015-01-01

    Bone morphogenetic proteins (BMPs), members of the TGF-β superfamily, have numerous biological activities including control of growth, differentiation, and vascular development. Using an in vitro co-culture endothelial cord formation assay, we investigated the role of a BMP7 variant (BMP7v) in VEGF, bFGF, and tumor-driven angiogenesis. BMP7v treatment led to disruption of neo-endothelial cord formation and regression of existing VEGF and bFGF cords in vitro. Using a series of tumor cell models capable of driving angiogenesis in vitro, BMP7v treatment completely blocked cord formation. Pre-treatment of endothelial cells with BMP7v significantly reduced their cord forming ability, indicating a direct effect on endothelial cell function. BMP7v activated the canonical SMAD signaling pathway in endothelial cells but targeted gene knockdown using shRNA directed against SMAD4 suggests this pathway is not required to mediate the anti-angiogenic effect. In contrast to SMAD activation, BMP7v selectively decreased ERK and AKT activation, significantly decreased endothelial cell migration and down-regulated expression of critical RTKs involved in VEGF and FGF angiogenic signaling, VEGFR2 and FGFR1 respectively. Importantly, in an in vivo angiogenic plug assay that serves as a measurement of angiogenesis, BMP7v significantly decreased hemoglobin content indicating inhibition of neoangiogenesis. In addition, BMP7v significantly decreased angiogenesis in glioblastoma stem-like cell (GSLC) Matrigel plugs and significantly impaired in vivo growth of a GSLC xenograft with a concomitant reduction in microvessel density. These data support BMP7v as a potent anti-angiogenic molecule that is effective in the context of tumor angiogenesis. PMID:25919028

  18. Curcumin inhibits advanced glycation end product-induced oxidative stress and inflammatory responses in endothelial cell damage via trapping methylglyoxal.

    PubMed

    Sun, Yan Ping; Gu, Jun Fei; Tan, Xiao Bin; Wang, Chun Fei; Jia, Xiao Bin; Feng, Liang; Liu, Ji Ping

    2016-02-01

    Methylglyoxal (MGO)-induced carbonyl stress and pro-inflammatory responses have been suggested to contribute to endothelial dysfunction. Curcumin (Cur), a polyphenolic compound from Curcuma longa L., may protect endothelial cells against carbonyl stress-induced damage by trapping dicarbonyl compounds such as MGO. However, Cur-MGO adducts have not been studied in depth to date and it remains to be known whether Cur-MGO adducts are able to attenuate endothelial damage by trapping MGO. In the present study, 1,2-diaminobenzene was reacted with MGO to ensure the reliability of the reaction system. Cur was demonstrated to trap MGO at a 1:1 ratio to form adducts 1, 2 and 3 within 720 min. The structures of these adducts were identified by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry. The kinetic curves of Cur (10(-7), 10(-6) and 10(-5) M) were measured from 0-168 h by fluorescent intensity. Cur significantly inhibited the formation of advanced glycation end products (AGEs). The differences in oxidative damage and the levels of pro-inflammatory cytokines following MGO + HSA or Cur-MGO treatment were investigated in human umbilical vein endothelial cells (HUVECs). Exposure of HUVECs to the Cur-MGO reaction adducts significantly reduced the intracellular ROS levels and improved cell viability compared with MGO alone. Furthermore, there was a significant reduction in the expression levels of transforming growth factor-β1 and intercellular adhesion molecule(-1) following treatment with Cur-MGO adducts compared with MGO alone. These results provide further evidence that the trapping of MGO by Cur inhibits the formation of AGEs. The current study indicates that the protective effect of Cur on carbonyl stress and pro-inflammatory responses in endothelial damage occurs via the trapping of MGO.

  19. Role of transforming growth factor-[beta]1 in inhibiting endothelial cell proliferation in experimental alcoholic liver disease.

    PubMed Central

    Nanji, A. A.; Tahan, S. R.; Golding, M.; Khwaja, S.; Rahemtulla, A.; Lalani, E. N.

    1996-01-01

    We used the intragastric feeding rat model for alcoholic liver disease to investigate the relationship between transforming growth factor (TGF)-beta 1 and inhibition of endothelial cell proliferation. Twelve groups of male Wistar rats (four to five rats per group) were fed ethanol or dextrose with either corn oil or saturated fat for 1-, 2-, and 4-week periods. All control animals were pair fed the same diets as ethanol-fed rats except that ethanol was isocalorically replaced by dextrose. In the ethanol-fed groups, nonparenchymal cells were isolated and TGF-beta 1 was measured in the nonparenchymal cell supernatant. Liver pathology and endothelial cell proliferation with an antibody to proliferating cell nuclear antigen were studied in all groups. Plasma TGF-beta 1 was measured in all rats. Pathological changes (fatty liver, necrosis, and inflammation) were observed only in the corn oil/ethanol-fed rats at 4 weeks. Significantly higher levels of TGF-beta 1 were seen in both plasma and nonparenchymal cell supernatant in rats fed corn oil and ethanol; plasma levels of TGF-beta 1 were not significantly different between the dextrose-fed controls and saturated fat/ethanol-fed rats. A significant inverse correlation (r = -0.89, P < 0.01) was seen between plasma TGF-beta 1 and the number of endothelial cells arrested at G1/S. Immunohistochemistry revealed the presence of TGF-beta 1 staining in interstitial macrophages only in rats fed corn oil and ethanol. The present study provides evidence for a role for TGF-beta 1 in inhibiting endothelial cell proliferation in experimental alcoholic liver disease. Arrest of endothelial cells may lead to their differentiation and/or to produce mediators that could stimulate other cells such as Ito cells. Sustained TGF-beta 1 may also lead to Ito cell production of extracellular matrix. Images Figure 1 Figure 2 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8774130

  20. Hantaviruses direct endothelial cell permeability by sensitizing cells to the vascular permeability factor VEGF, while angiopoietin 1 and sphingosine 1-phosphate inhibit hantavirus-directed permeability.

    PubMed

    Gavrilovskaya, Irina N; Gorbunova, Elena E; Mackow, Natalie A; Mackow, Erich R

    2008-06-01

    Hantaviruses infect human endothelial cells and cause two vascular permeability-based diseases: hemorrhagic fever with renal syndrome and hantavirus pulmonary syndrome. Hantavirus infection alone does not permeabilize endothelial cell monolayers. However, pathogenic hantaviruses inhibit the function of alphav beta3 integrins on endothelial cells, and hemorrhagic disease and vascular permeability deficits are consequences of dysfunctional beta3 integrins that normally regulate permeabilizing vascular endothelial growth factor (VEGF) responses. Here we show that pathogenic Hantaan, Andes, and New York-1 hantaviruses dramatically enhance the permeability of endothelial cells in response to VEGF, while the nonpathogenic hantaviruses Prospect Hill and Tula have no effect on endothelial cell permeability. Pathogenic hantaviruses directed endothelial cell permeability 2 to 3 days postinfection, coincident with pathogenic hantavirus inhibition of alphav beta3 integrin functions, and hantavirus-directed permeability was inhibited by antibodies to VEGF receptor 2 (VEGFR2). These studies demonstrate that pathogenic hantaviruses, similar to alphav beta3 integrin-deficient cells, specifically enhance VEGF-directed permeabilizing responses. Using the hantavirus permeability assay we further demonstrate that the endothelial-cell-specific growth factor angiopoietin 1 (Ang-1) and the platelet-derived lipid mediator sphingosine 1-phosphate (S1P) inhibit hantavirus directed endothelial cell permeability at physiologic concentrations. These results demonstrate the utility of a hantavirus permeability assay and rationalize the testing of Ang-1, S1P, and antibodies to VEGFR2 as potential hantavirus therapeutics. The central importance of beta3 integrins and VEGF responses in vascular leak and hemorrhagic disease further suggest that altering beta3 or VEGF responses may be a common feature of additional viral hemorrhagic diseases. As a result, our findings provide a potential mechanism

  1. The effects of direct thrombin inhibition with dabigatran on plaque formation and endothelial function in apolipoprotein E-deficient mice.

    PubMed

    Lee, Illkyu-O; Kratz, Mario T; Schirmer, Stephan H; Baumhäkel, Magnus; Böhm, Michael

    2012-11-01

    The recently developed oral anticoagulant dabigatran (Dabi) etexilate directly inhibits thrombin after activation by plasma esterases to dabigatran. Thrombin is involved in the pathogenesis of atherosclerosis. We investigated the effects of direct thrombin inhibition on atherosclerosis and endothelial function in a hypercholesterolemic mouse model with accelerated atherosclerosis {[apolipoprotein E-deficient (ApoE(-/-)] mice}. ApoE(-/-) mice were treated with a cholesterol-rich diet for 12 weeks and either dabigatran etexilate (900 mg/kg body weight) or vehicle. Wild-type (C57/B6) mice served as control. Endothelial function was assessed with carbachol (endothelium dependent) by using glyceroltrinitrate (endothelium independent) as control in aortic rings. Atherosclerotic lesion formation was evaluated with Oil Red staining, and vascular collagen content was determined by Sirius Red staining. Reactive oxygen species (ROS) production was determined by semiquantitative immunohistochemical staining. Measurement of dabigatran plasma levels (622.3±169 ng/ml) and a performed coagulation test (diluted thrombin time) revealed a relevant anticoagulatory concentration. Dabigatran etexilate attenuated increased atherosclerotic plaque formation [ApoE(-/-) Dabi: 16.1±3.8% of ApoE(-/-) control; p<0.001], decreased collagen content [ApoE(-/-) Dabi: 49.1±10% of ApoE(-/-) control; p=0.01], and ROS production in dihydroethidium staining [ApoE(-/-) Dabi: 46.3±5.4% of ApoE(-/-) control; p=0.005] in parallel to an improvement of endothelial function [ApoE(-/-) control 42.6±2.7 versus ApoE(-/-) Dabi 62.9±3.3% of phenylephrine-induced contraction; p=0.001] at 100 μmol carbachol. These data suggest that direct thrombin inhibition in a relevant dosage improved endothelial function and reduced atherosclerotic lesion size, collagen content, and oxidative stress in hypercholesterolemic atherosclerosis. Interference with the coagulation system might provide a therapeutic target to

  2. Hydroxytyrosol targets extracellular matrix remodeling by endothelial cells and inhibits both ex vivo and in vivo angiogenesis.

    PubMed

    García-Vilas, Javier A; Quesada, Ana R; Medina, Miguel Ángel

    2017-04-15

    The health benefits of olive oil are attributed to their bioactive compounds, such as hydroxytyrosol. Previously, we demonstrated that hydroxytyrosol inhibits angiogenesis in vitro. The present study aimed to: i) get further insight into the effects of hydroxytyrosol on extracellular matrix remodeling; and ii) test whether hydroxytyrosol is able to inhibit angiogenesis ex vivo and in vivo. Hydroxytyrosol induced a shift toward inhibition of proteolysis in endothelial cells, with decreased expression of extracellular matrix remodeling-enzyme coding genes and increased levels of some of their inhibitors. Furthermore, this work demonstrated that hydroxytyrosol, at concentrations within the range of its content in virgin olive oil that can be absorbed from moderate and sustained virgin olive oil consumption, is a strong inhibitor of angiogenesis ex vivo and in vivo. These results suggest the need for translational studies to evaluate the potential use of hydroxytyrosol for angio-prevention and angiogenesis inhibition in clinical setting.

  3. Rapamycin Inhibits Proliferation of Hemangioma Endothelial Cells by Reducing HIF-1-Dependent Expression of VEGF

    PubMed Central

    Medici, Damian; Olsen, Bjorn R.

    2012-01-01

    Hemangiomas are tumors formed by hyper-proliferation of vascular endothelial cells. This is caused by elevated vascular endothelial growth factor (VEGF) signaling through VEGF receptor 2 (VEGFR2). Here we show that elevated VEGF levels produced by hemangioma endothelial cells are reduced by the mTOR inhibitor rapamycin. mTOR activates p70S6K, which controls translation of mRNA to generate proteins such as hypoxia inducible factor-1 (HIF-1). VEGF is a known HIF-1 target gene, and our data show that VEGF levels in hemangioma endothelial cells are reduced by HIF-1α siRNA. Over-expression of HIF-1α increases VEGF levels and endothelial cell proliferation. Furthermore, both rapamycin and HIF-1α siRNA reduce proliferation of hemangioma endothelial cells. These data suggest that mTOR and HIF-1 contribute to hemangioma endothelial cell proliferation by stimulating an autocrine loop of VEGF signaling. Furthermore, mTOR and HIF-1 may be therapeutic targets for the treatment of hemangiomas. PMID:22900063

  4. Suppression of complement regulatory protein C1 inhibitor in vascular endothelial activation by inhibiting vascular cell adhesion molecule-1 action

    SciTech Connect

    Zhang, Haimou; Qin, Gangjian; Liang, Gang; Li, Jinan; Chiu, Isaac; Barrington, Robert A.; Liu, Dongxu . E-mail: dxliu001@yahoo.com

    2007-07-13

    Increased expression of adhesion molecules by activated endothelium is a critical feature of vascular inflammation associated with the several diseases such as endotoxin shock and sepsis/septic shock. Our data demonstrated complement regulatory protein C1 inhibitor (C1INH) prevents endothelial cell injury. We hypothesized that C1INH has the ability of an anti-endothelial activation associated with suppression of expression of adhesion molecule(s). C1INH blocked leukocyte adhesion to endothelial cell monolayer in both static assay and flow conditions. In inflammatory condition, C1INH reduced vascular cell adhesion molecule (VCAM-1) expression associated with its cytoplasmic mRNA destabilization and nuclear transcription level. Studies exploring the underlying mechanism of C1INH-mediated suppression in VCAM-1 expression were related to reduction of NF-{kappa}B activation and nuclear translocation in an I{kappa}B{alpha}-dependent manner. The inhibitory effects were associated with reduction of inhibitor I{kappa}B kinase activity and stabilization of the NF-{kappa}B inhibitor I{kappa}B. These findings indicate a novel role for C1INH in inhibition of vascular endothelial activation. These observations could provide the basis for new therapeutic application of C1INH to target inflammatory processes in different pathologic situations.

  5. Renal endothelial function is associated with the anti-proteinuric effect of ACE inhibition in 5/6 nephrectomized rats.

    PubMed

    Vettoretti, Simone; Vavrinec, Peter; Ochodnicky, Peter; Deelman, Leo E; De Zeeuw, Dick; Henning, Rob H; Buikema, Hendrik

    2016-05-01

    In healthy rats, the physiological variation of baseline endothelial function of intrarenal arteries correlates with the severity of renal damage in response to a subsequent specific renal injury. However, whether such a variation in endothelial function may also condition or predict the variable response to angiotensin-converting enzyme-inhibiting treatment in these individuals has not been addressed before. To study this, 5/6 nephrectomy was performed to induce renal injury and chronic kidney disease in a group of healthy Wistar rats. At the time of nephrectomy, interlobar arteries were obtained from the extirpated right kidney and studied in vitro for endothelium-dependent relaxation to acetylcholine. Six weeks thereafter, treatment with lisinopril was started (n = 11) and continued for 9 wk. Proteinuria (metabolic cages) and systolic blood pressure (SBP; tail cuff) were evaluated weekly, and these were analyzed in relation to renal endothelial function at baseline. 5/6 Nephrectomy induced an increase in SBP and progressive proteinuria. Treatment with lisinopril reduced SBP and slowed proteinuria, albeit to a variable degree among individuals. The acetylcholine-induced renal artery dilation at baseline negatively correlated with lisinopril-induced reduction of proteinuria (r(2) = 0.648, P = 0.003) and with the decrease in SBP (r(2) = 0.592, P = 0.006). Our data suggest that angiotensin-converting enzyme-inhibitor attenuates the progression of renal damage the most in those individuals with decreased basal renal endothelial-mediated vasodilation.

  6. MicroRNA-221/222 regulate ox-LDL-induced endothelial apoptosis via Ets-1/p21 inhibition.

    PubMed

    Qin, Bing; Cao, Yuze; Yang, Huan; Xiao, Bo; Lu, Zhengqi

    2015-07-01

    Endothelial cells (ECs) apoptosis induced by oxidized low-density lipoprotein (ox-LDL) is thought to play an essential role in atherosclerosis. MicroRNAs (miRNAs) are a class of short non-coding RNAs, acting as posttranscriptional regulators of protein-coding genes involved in vascular cell biology. MiRNA-221 and miRNA-222 (miR-221/222) are known to be involved in the regulation of endothelial inflammation and angiogenesis. However, the function of miR-221/222 in ox-LDL-induced ECs apoptosis and atherosclerosis is still unknown. Here, we showed that miR-221/222 expression was markedly down-regulated in ox-LDL-induced apoptotic human umbilical cord vein endothelial cells. MiR-221/222 inhibition enhanced apoptosis in ECs, whereas over-expression of miR-221/222 could partly alleviate apoptotic cell death mediated by ox-LDL through suppression of Ets-1 and its downstream target p21. These findings suggest that manipulation of the miR-221/222-Ets-1-p21 pathway may offer a novel strategy for treatment of endothelial apoptosis and atherosclerosis.

  7. Repair of wounded monolayers of cultured bovine aortic endothelial cells is inhibited by calcium spirulan, a novel sulfated polysaccharide isolated from Spirulina platensis.

    PubMed

    Kaji, Toshiyuki; Fujiwara, Yasuyuki; Inomata, Yuki; Hamada, Chieko; Yamamoto, Chika; Shimada, Satomi; Lee, Jung-Bum; Hayashi, Toshimitsu

    2002-03-08

    Calcium spirulan (Ca-SP) is a novel sulfated polysaccharide isolated from a blue-green alga Spirulina platensis. Ca-SP inhibits thrombin by activation of heparin cofactor II. Therefore, it could serve as an origin of anti-atherogenic medicines. Since maintenance of vascular endothelial cell monolayers is important for prevention of vascular lesions such as atherosclerosis, the effect of Ca-SP at 20 microg/ml or less on the repair of wounded bovine aortic endothelial cell monolayers in culture was investigated in the present study. When the monolayers were wounded and cultured in the presence of Ca-SP, the polysaccharide inhibited the appearance of the cells in the wounded area. The inhibition was also observed even when the repair was promoted by excess basic fibroblast growth factor, which is one of the autocrine growth factors that are involved in the endothelial cell monolayer maintenance. On the other hand, Ca-SP inhibited the cell growth and the incorporation of [3H]thymidine into the acid-insoluble fraction of proliferating endothelial cells, suggesting that Ca-SP inhibits endothelial cell proliferation. From these results, it is concluded that Ca-SP may retard the repair process of damaged vascular endothelium through inhibition of vascular endothelial cell proliferation by induction of a lower ability to respond to stimulation by endogenous basic fibroblast growth factor.

  8. Plasma-derived and synthetic high-density lipoprotein inhibit tissue factor in endothelial cells and monocytes.

    PubMed

    Ossoli, Alice; Remaley, Alan T; Vaisman, Boris; Calabresi, Laura; Gomaraschi, Monica

    2016-01-15

    HDL (high-density lipoproteins) exert anti-thrombotic activities by preventing platelet adhesion and activation and by stimulating the protein C pathway and fibrinolysis. The aim of the present study was to assess the effect of plasma-derived and synthetic HDL on endothelial and monocyte expression of TF (tissue factor), the primary initiator of coagulation. HDL inhibited TF expression and activity in stimulated endothelial cells and monocytes in a dose-dependent way. Synthetic HDL fully retain the ability to inhibit TF expression in a dose-dependent manner; lipid-free apoA-I (apolipoprotein A-I) was not effective and neither was sphingosine 1-phosphate involved. HDL-mediated TF inhibition was due to a modulation of cellular cholesterol content through the interaction with SR-BI (scavenger receptor BI); downstream, HDL inhibited the activation of p38 MAPK (mitogen-activated protein kinase) and the repression of the PI3K (phosphoinositide 3-kinase) pathway responsible for TF expression. In vivo, human apoA-I-transgenic mice displayed a reduced aortic TF expression compared with wild-type animals and TF plasma levels were increased in subjects with low HDL-C (HDL-cholesterol) levels compared with high HDL-C subjects. Thus the anti-thrombotic activity of HDL could also be mediated by the inhibition of TF expression and activity in endothelial cells and monocytes; synthetic HDL retain the inhibitory activity of plasma-derived HDL, supporting the hypothesis that synthetic HDL infusion may be beneficial in the setting of acute coronary syndrome. © 2016 Authors; published by Portland Press Limited.

  9. Current status of vascular endothelial growth factor inhibition in age-related macular degeneration.

    PubMed

    Mousa, Shaker A; Mousa, Shaymaa S

    2010-06-01

    Angiogenesis, the process by which new vessels are created from pre-existing vasculature, has become the subject of intense research in recent years. Increased rates of angiogenesis are associated with several disease states, including cancer, age-related macular degeneration (AMD), psoriasis, rheumatoid arthritis, and diabetic retinopathy. Vascular endothelial growth factor (VEGF) is an important modulator of angiogenesis, and has been implicated in the pathology of a number of conditions, including AMD, diabetic retinopathy, and cancer. AMD is a progressive disease of the macula and the third major cause of blindness worldwide. If not treated appropriately, AMD can progress to involve both eyes. Until recently, the treatment options for AMD have been limited, with photodynamic therapy (PDT) the mainstay of treatment. Although PDT is effective at slowing disease progression, it rarely results in improved vision. Several therapies have been or are now being developed for neovascular AMD, with the goal of inhibiting VEGF. These VEGF inhibitors include the RNA aptamer pegaptanib, partial and full-length antibodies ranibizumab and bevacizumab, the VEGF receptor decoy aflibercept, small interfering RNA-based therapies bevasiranib and AGN 211745, sirolimus, and tyrosine kinase inhibitors, including vatalanib, pazopanib, TG 100801, TG 101095, AG 013958, and AL 39324. At present, established therapies have met with great success in reducing the vision loss associated with neovascular AMD, whereas those still under investigation offer the potential for further advances. In AMD patients, these therapies slow the rate of vision loss and in some cases increase visual acuity. Although VEGF-inhibitor therapies are a milestone in the treatment of these disease states, several concerns need to be addressed before their impact can be fully realized.

  10. 8,9-Dehydrohispanolone-15,16-lactol diterpene prevents LPS-triggered inflammatory responses by inhibiting endothelial activation.

    PubMed

    Jiménez-García, Lidia; Través, Paqui G; López-Fontal, Raquel; Herranz, Sandra; Higueras, María Angeles; de Las Heras, Beatriz; Hortelano, Sonsoles; Luque, Alfonso

    2016-07-15

    Endothelial activation contributes to lung inflammatory disorders by inducing leucocyte recruitment to pulmonary parenchyma. Consequently, vascular-targeted therapies constitute promising strategies for the treatment of inflammatory pathologies. In the present study, we evaluated the effect of 8,9-dehydrohispanolone-15,16-lactol diterpene (DT) on lung endothelium during inflammation. Lung endothelial cells pre-treated with DT and activated with lipopolysaccharide (LPS) or tumour necrosis factor-α (TNF-α) exhibited reduced expression of the pro-inflammatory cytokines Cxcl10, Ccl5 and Cxcl1, whereas the anti-inflammatory molecules IL1r2 and IL-10 were induced. Consistent with this result, DT pre-treatment inhibited nuclear factor κB (NF-κB) nuclear translocation, by interfering with IκBα phosphorylation, and consequently NF-κB transcriptional activity in endothelium activated by LPS or TNF-α. Furthermore, DT, probably through p38 signalling, induced transcriptional activation of genes containing activator protein 1 (AP-1)-binding elements. Inhibition of p38 prevented IL1r2 mRNA expression in endothelium incubated with DT alone or in combination with LPS or TNF-α. Accordingly, conditioned medium (CM) from these cells failed to stimulate leucocytes as measured by a reduction in adhesive ability of the leucocyte cell line J774 to fibronectin (FN). Additionally, DT reduced the expression of the endothelial adhesion molecules E-selectin, vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) after activation. Similarly, expression of VCAM-1 and ICAM-1 molecules on the lung endothelial layer of C57/BL6 mice pre-treated with DT and challenged with LPS were unchanged. Finally, inhibition of vascular adhesion molecule expression by DT decreased the interaction of J774 cells with lung endothelial cells in an inflammatory environment. Our findings establish DT as a novel endothelial inhibitor for the treatment of inflammatory

  11. Dihydroartemisinin inhibits vascular endothelial growth factor-induced endothelial cell migration by a p38 mitogen-activated protein kinase-independent pathway.

    PubMed

    Guo, Ling; Dong, Fengyun; Hou, Yinglong; Cai, Weidong; Zhou, Xia; Huang, Ai-Ling; Yang, Min; Allen, Thaddeus D; Liu, Ju

    2014-12-01

    Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, has been demonstrated to possess a strong antiangiogenic activity. However, the molecular mechanisms underlying this effect remain unclear. Endothelial cell (EC) migration is an essential component of angiogenesis, and the p38 mitogen-activated protein kinase (MAPK) signaling pathway plays a key role in the regulation of migration induced by vascular endothelial growth factor (VEGF). The aim of the present study was to investigate the effects of DHA on EC migration and the p38 MAPK signaling pathway. Human umbilical vein ECs (HUVECs) were treated with DHA and VEGF-induced migration was analyzed. The activation of p38 MAPK was detected by western blot analysis, and the migration assays were performed with a p38-specific inhibitor, SB203850. It was revealed that 20 μM DHA significantly reduced EC migration in the transwell migration assay, wound healing assay and electrical cell-substrate impedance sensing real-time analysis. However, DHA did not affect p38 MAPK phosphorylation or expression. In the absence or presence of SB203850, DHA induced a similar proportional reduction of EC migration in the three migration assays. Therefore, the present study demonstrated that DHA inhibits VEGF-induced EC migration via a p38 MAPK-independent pathway.

  12. Deguelin inhibits vasculogenic function of endothelial progenitor cells in tumor progression and metastasis via suppression of focal adhesion.

    PubMed

    Nguyen, Minh Phuong; Lee, Dongjin; Lee, Se-Hyung; Lee, Hye-Eun; Lee, Ho-Young; Lee, You Mie

    2015-06-30

    Deguelin is a nature-derived chemopreventive drug. Endothelial progenitor cells (EPCs) are bone-marrow (BM)-derived key components to induce new blood vessels in early tumorigenesis and metastasis. Here we determined whether deguelin inhibits EPC function in vitro and in vivo at doses not affecting cancer cell apoptosis. Deguelin significantly reduced the number of EPC colony forming units of BM-derived c-kit+/sca-1+ mononuclear cells (MNCs), proliferation, migration, and adhesion to endothelial cell monolayers, and suppressed incorporation of EPC into tube-like vessel networks when co-cultured with endothelial cells. Deguelin caused cell cycle arrest at G1 without induction of apoptosis in EPC. In a mouse tumor xenograft model, tumor growth, lung metastasis and tumor-induced circulating EPCs were supressed by deguelin treatment (2 mg/kg). In mice tranplanted with GFP-expressing BM-MNCs, deguelin reduced the co-localization of CD31 and GFP, suggesting suppression of BM-derived EPC incoporation into tumor vessels. Interestingly, focal adhesion kinase (FAK)-integrin-linked kinase (ILK) activation and actin polymerization were repressed by deguelin. Decreased number of focal adhesions and a depolarized morphology was found in deguelin-treated EPCs. Taken together, our results suggest that the deguelin inhibits tumorigenesis and metastasis via EPC suppression and that suppression of focal adhesion by FAK-integrin-ILK-dependent actin remodeling is a key underlying molecular mechanism.

  13. Maprotiline inhibits LPS-induced expression of adhesion molecules (ICAM-1 and VCAM-1) in human endothelial cells

    PubMed Central

    Rafiee, Laleh; Hajhashemi, Valiollah; Javanmard, Shaghayegh Haghjooy

    2016-01-01

    Regardless of the known anti-inflammatory potential of heterocyclic antidepressants, the mechanisms concerning their modulating effects are not completely known. In our earlier work, maprotiline, a heterocyclic antidepressants, considerably inhibited infiltration of polymorphonuclear cell leucocytes into the inflamed paw. To understand the mechanism involved, we evaluated the effect of vascular cell adhesion molecule (VCAM-1), intracellular adhesion molecule (ICAM-1) expression in stimulated endothelial cells. Endothelial cells were stimulated with lipopolysaccharide (LPS) in the presence and absence of maprotiline (10-8 to 10-6 M) and ICAM-1 and VCAM-1 expression were measured using real-time quantitative reverse transcription polymerase chain reaction. Maprotiline significantly decreased the LPS-induced expression of VCAM-1 at all applied concentrations. The expression of ICAM-1 decreased in the presence of maprotiline at 10-6 M concentration (P<0.05). Since maprotiline inhibits the expression of adhesion molecules, ICAM-1 and VCAM-1 in LPS-stimulated human endothelial cells, it can be a possible way through which maprotiline exerts its anti-inflammatory properties. PMID:27168753

  14. Estradiol augments while progesterone inhibits arginine transport in human endothelial cells through modulation of cationic amino acid transporter-1.

    PubMed

    Bentur, Ohad S; Schwartz, Doron; Chernichovski, Tamara; Ingbir, Merav; Weinstein, Talia; Chernin, Gil; Schwartz, Idit F

    2015-08-15

    Decreased generation of nitric oxide (NO) by endothelial NO synthase (eNOS) characterizes endothelial dysfunction (ECD). Delivery of arginine to eNOS by cationic amino acid transporter-1 (CAT-1) was shown to modulate eNOS activity. We found in female rats, but not in males, that CAT-1 activity is preserved with age and in chronic renal failure, two experimental models of ECD. In contrast, during pregnancy CAT-1 is inhibited. We hypothesize that female sex hormones regulate arginine transport. Arginine uptake in human umbilical vein endothelial cells (HUVEC) was determined following incubation with either 17β-estradiol (E2) or progesterone. Exposure to E2 (50 and 100 nM) for 30 min resulted in a significant increase in arginine transport and reduction in phosphorylated CAT-1 (the inactive form) protein content. This was coupled with a decrease in phosphorylated MAPK/extracellular signal-regulated kinase (ERK) 1/2. Progesterone (1 and 100 pM for 30 min) attenuated arginine uptake and increased phosphorylated CAT-1, phosphorylated protein kinase Cα (PKCα), and phosphorylated ERK1/2 protein content. GO-6976 (PKCα inhibitor) prevented the progesterone-induced decrease in arginine transport. Coincubation with both progesterone and estrogen for 30 min resulted in attenuated arginine transport. While estradiol increases arginine transport and CAT-1 activity through modulation of constitutive signaling transduction pathways involving ERK, progesterone inhibits arginine transport and CAT-1 via both PKCα and ERK1/2 phosphorylation, an effect that predominates over estradiol.

  15. Cyclosporin A inhibits flow-mediated activation of endothelial nitric-oxide synthase by altering cholesterol content in caveolae.

    PubMed

    Lungu, Andreea O; Jin, Zheng-Gen; Yamawaki, Hideyuki; Tanimoto, Tatsuo; Wong, Chelsea; Berk, Bradford C

    2004-11-19

    Fluid shear stress generated by blood flowing over the endothelium is a major determinant of arterial tone, vascular remodeling, and atherogenesis. Nitric oxide (NO) produced by endothelial NO synthase (eNOS) plays an essential role in regulation of vascular function and structure by blood flow. Although cyclosporin A (CsA), an inhibitory ligand of cyclophilin A, is a widely used immunosuppressive drug, it causes arterial hypertension in part by impairing eNOS-dependent vasodilation. Here we show that CsA inhibits fluid shear stress-mediated eNOS activation in endothelial cells via decreasing cholesterol content in caveolae. Exposure of cultured bovine aortic endothelial cells to 1 mum CsA for 1 h significantly inhibited NO production and eNOS phosphorylation at Ser-1179 induced by flow (shear stress=dynes/cm2). The effect of CsA was not related to inhibition of two known eNOS kinases, protein kinase B (Akt) and protein kinase A, because CsA did not affect Akt or protein kinase A activation. In rabbit aorta perfused ex vivo, CsA also significantly inhibited flow-induced eNOS phosphorylation at Ser-1179 but had no effect on Akt measured by phosphorylation at Ser-473. However, CsA treatment decreased cholesterol content in caveolae and displaced eNOS from caveolae, which may be caused by CsA disrupting the association of caveolin-1 and cyclophilin A. The magnitude of the cholesterol depleting effect was similar to that of beta-cyclodextrin, a cholesterol-binding molecule, and beta-cyclodextrin had a similar inhibitory effect on flow-mediated eNOS activation. Treating bovine aortic endothelial cells for 24 h with 30 mug/ml cholesterol blocked the CsA effect and restored eNOS phosphorylation in response to flow. These data suggest that decreasing cholesterol content in caveolae by CsA is a potentially important pathogenic mechanism for CsA-induced endothelial dysfunction and hypertension.

  16. Indolyl-quinuclidinols inhibit ENOX activity and endothelial cell morphogenesis while enhancing radiation-mediated control of tumor vasculature

    PubMed Central

    Geng, Ling; Rachakonda, Girish; Morré, D. James; Morré, Dorothy M.; Crooks, Peter A.; Sonar, Vijayakumar N.; Roti, Joseph L. Roti; Rogers, Buck E.; Greco, Suellen; Ye, Fei; Salleng, Kenneth J.; Sasi, Soumya; Freeman, Michael L.; Sekhar, Konjeti R.

    2009-01-01

    There is a need for novel strategies that target tumor vasculature, specifically those that synergize with cytotoxic therapy, in order to overcome resistance that can develop with current therapeutics. A chemistry-driven drug discovery screen was employed to identify novel compounds that inhibit endothelial cell tubule formation. Cell-based phenotypic screening revealed that noncytotoxic concentrations of (Z)-(±)-2-(1-benzenesulfonylindol-3-ylmethylene)-1-azabicyclo[2. 2.2]octan-3-ol (analog I) and (Z)-(±)-2-(1-benzylindol-3-ylmethylene)-1-azabicyclo[2.2.2]octan-3-ol (analog II) inhibited endothelial cell migration and the ability to form capillary-like structures in Matrigel by ≥70%. The ability to undergo neoangiogenesis, as measured in a window-chamber model, was also inhibited by 70%. Screening of biochemical pathways revealed that analog II inhibited the enzyme ENOX1 (EC50 = 10 μM). Retroviral-mediated shRNA suppression of endothelial ENOX1 expression inhibited cell migration and tubule formation, recapitulating the effects observed with the small-molecule analogs. Genetic or chemical suppression of ENOX1 significantly increased radiation-mediated Caspase3-activated apoptosis, coincident with suppression of p70S6K1 phosphorylation. Administration of analog II prior to fractionated X-irradiation significantly diminished the number and density of tumor microvessels, as well as delayed syngeneic and xenograft tumor growth compared to results obtained with radiation alone. Analysis of necropsies suggests that the analog was well tolerated. These results suggest that targeting ENOX1 activity represents a novel therapeutic strategy for enhancing the radiation response of tumors.—Geng, L., Rachakonda, G., Morré, D. J., Morré, D. M., Crooks, P. A., Sonar, V. N., Roti Roti, J. L., Rogers, B. E., Greco, S., Ye, F., Salleng, K. J., Sasi, S., Freeman, M. L., Sekhar, K. R. Indolyl-quinuclidinols inhibit ENOX activity and endothelial cell morphogenesis while

  17. Nitric Oxide Inhibits Hetero-adhesion of Cancer Cells to Endothelial Cells: Restraining Circulating Tumor Cells from Initiating Metastatic Cascade

    NASA Astrophysics Data System (ADS)

    Lu, Yusheng; Yu, Ting; Liang, Haiyan; Wang, Jichuang; Xie, Jingjing; Shao, Jingwei; Gao, Yu; Yu, Suhong; Chen, Shuming; Wang, Lie; Jia, Lee

    2014-03-01

    Adhesion of circulating tumor cells (CTCs) to vascular endothelial bed becomes a crucial starting point in metastatic cascade. We hypothesized that nitric oxide (NO) may prevent cancer metastasis from happening by its direct vasodilation and inhibition of cell adhesion molecules (CAMs). Here we show that S-nitrosocaptopril (CAP-NO, a typical NO donor) produced direct vasorelaxation that can be antagonized by typical NO scavenger hemoglobin and guanylate cyclase inhibitor. Cytokines significantly stimulated production of typical CAMs by the highly-purified human umbilical vein endothelial cells (HUVECs). CAP-NO inhibited expression of the stimulated CAMs (particularly VCAM-1) and the resultant hetero-adhesion of human colorectal cancer cells HT-29 to the HUVECs in a concentration-dependent manner. The same concentration of CAP-NO, however, did not significantly affect cell viability, cell cycle and mitochondrial membrane potential of HT-29, thus excluding the possibility that inhibition of the hetero-adhesion was caused by cytotoxicity by CAP-NO on HT-29. Hemoglobin reversed the inhibition of CAP-NO on both the hetero-adhesion between HT-29 and HUVECs and VCAM-1 expression. These data demonstrate that CAP-NO, by directly releasing NO, produces vasorelaxation and interferes with hetero-adhesion of cancer cells to vascular endothelium via down-regulating expression of CAMs. The study highlights the importance of NO in cancer metastatic prevention.

  18. Prevention of VEGF-induced growth and tube formation in human retinal endothelial cell by aldose reductase inhibition

    PubMed Central

    Yadav, Umesh CS; Srivastava, SK; Ramana, KV

    2012-01-01

    Objective Since diabetes-induced vascular endothelial growth factor (VEGF) is implicated in retinal angiogenesis, we aimed to examine the role of aldose reductase (AR) in VEGF–induced human retinal endothelial cell (HREC) growth and tube formation. Materials and Methods HREC were stimulated with VEGF and cell-growth was determined by MTT assay. AR inhibitor, fidarestat, to block the enzyme activity and AR siRNA to ablate AR gene expression in HREC were used to investigate the role of AR in neovascularization using cell-migration and tube formation assays. Various signaling intermediates and angiogenesis markers were assessed by Western blot analysis. Immuno-histochemical analysis of diabetic rat eyes was performed to examine VEGF expression in the retinal layer. Results Stimulation of primary HREC with VEGF caused increased cell growth and migration, and AR inhibition with fidarestat or ablation with siRNA significantly prevented it. VEGF-induced tube formation in HREC was also significantly prevented by fidarestat. Treatment of HREC with VEGF also increased the expression of VCAM, AR, and phosphorylation and activation of Akt and p38-MAP kinase, which were prevented by fidarestat. VEGF-induced expression of VEGFRII in HREC was also prevented by AR inhibition or ablation. Conclusions Our results indicate that inhibition of AR in HREC prevents tube formation by inhibiting the VEGF-induced activation of the Akt and p38-MAPK pathway and suggest a mediatory role of AR in ocular neovascularization generally implicated in retinopathy and AMD. PMID:22658411

  19. Antiproliferation in human EA.hy926 endothelial cells and inhibition of VEGF expression in PC-3 cells by topotecan.

    PubMed

    Yang, Xiaochun; Zhang, Chong; Ying, Meidan; Yang, Bo; He, Qiaojun

    2007-07-01

    Protracted administration of topotecan (TPT), a topoisomerase I inhibitor, exhibited high anticancer efficacy both in animal models and human cancers. This phenomenon is related to the TPT-induced inhibition of angiogenesis in tumor, but the potential mechanism remains largely unknown. In the present study, we reported that TPT (1-10 microM) could inhibit angiogenesis in a dose-dependent manner in Chick embryo chorioallantoic membrane (CAM) assay. TPT showed strong inhibitory activity against proliferation on human EA.hy926 endothelial cells with an IC50 value of 0.13 microM (MTT assay), lower than that of most sensitive cancer cell lines (IC50 range, 0.17 microM to 5.1 microM). TPT could induce EA.hy926 cells undergoing apoptosis, and the percentage of apoptotic cells induced by TPT (0.05 microM-5.0 microM) were 17.9%-52.3%. The similar results were observed with AO/EB staining. Flow cytometry assay also revealed that various concentrations of TPT induced cell cycle disturbance in EA.hy926 cells. Western blotting results showed that TPT caused an obvious increase of p53 expression and a decline of ERK expression in EA.hy926 cells. In addition, the VEGF expression of PC-3 cells is inhibited by TPT in hypoxia. Altogether, inhibiting proliferation of endothelial cells and down-regulating VEGF expression in cancer cells may involve in the antiangiogenesis mechanism of TPT.

  20. Omentin inhibits TNF-α-induced expression of adhesion molecules in endothelial cells via ERK/NF-κB pathway.

    PubMed

    Zhong, Xia; Li, Xiaonan; Liu, Fuli; Tan, Hui; Shang, Deya

    2012-08-24

    In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-α (TNF-α) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-α-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibited TNF-α-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-α-activated signal pathway of nuclear factor-κB (NF-κB) by preventing NF-κB inhibitory protein (IκBα) degradation and NF-κB/DNA binding activity. Omentin pretreatment significantly inhibited TNF-α-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-α-induced NF-κB activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-α. These results suggest that omentin may inhibit TNF-α-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-κB pathway.

  1. Protection of glycyrrhizic acid against AGEs-induced endothelial dysfunction through inhibiting RAGE/NF-κB pathway activation in human umbilical vein endothelial cells.

    PubMed

    Feng, Liang; Zhu, Mao-Mao; Zhang, Ming-Hua; Wang, Ru-Shang; Tan, Xiao-Bin; Song, Jie; Ding, Shu-Min; Jia, Xiao-Bin; Hu, Shao-Ying

    2013-06-21

    Licorice (Glycyrrhiza uralensis roots) is used as a traditional medicine for the treatment of diabetes mellitus and its vascular complications. Glycyrrhizic acid (GA, also known as Glycyrrhizin), a triterpenoid saponin glycoside, is considered to be a bioactive component in Licorice and is beneficial to diabetic vascular complications. The present study was conducted to evaluate the potential protective activities on AGEs-induced endothelial dysfunction, including anti-apoptosis, antioxidant stress and anti-proinflammatory responses, and explore the underlying mechanism. Human umbilical vein endothelial cells (HUVECs) were incubated and pre-treated with GA (10(-9)-10(-6)M) or RAGE-Ab (5μg/ml) in the presence or absence of 200μg/ml AGEs. AO/EB fluorescence staining assay was performed to evaluate anti-apoptosis activity. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in cell supernatant were detected by kits while the intracellular reactive oxygen species (ROS) generation was determined by 2,7-dichlorodihydrofluorescin diacetate (DCFH-DA) kit. Immunocytochemistry analysis was designed to determine transforming growth factor beta1(TGF-β1) protein expression while immunofluorescence analysis for RAGE and NF-kB. The protein expressions of TGF-β1, RAGE and NF-kB were analyzed by Western blot analysis. Pretreatment with GA at a concentration of 10(-8)-10(-6)M significantly reduced the AGEs-induced apoptosis in HUVECs. GA significantly increased antioxidant enzyme SOD activity and decreased peroxide degradation product MDA level in a dose-dependent manner. Furthermore, GA also remarkably inhibited the overgeneration of AGEs-induced ROS. Both immunocytochemistry analysis and western blot analysis showed that GA significantly decreased the protein expression of poinflammatory cytokine TGF-β1 in a similar manner which RAGE-Ab did. Additionally, AGEs-induced RAGE and NF-kB protein expressions were down-regulated significantly by the pretreatment

  2. Inhibition of vascular endothelial growth factor signaling facilitates liver repair from acute ethanol-induced injury in zebrafish

    PubMed Central

    Zhang, Changwen; Ellis, Jillian L.

    2016-01-01

    ABSTRACT Alcoholic liver disease (ALD) results from alcohol overconsumption and is among the leading causes of liver-related morbidity and mortality worldwide. Elevated expression of vascular endothelial growth factor (VEGF) and its receptors has been observed in ALD, but how it contributes to ALD pathophysiology is unclear. Here, we investigated the impact of VEGF signaling inhibition on an established zebrafish model of acute alcoholic liver injury. Kdrl activity was blocked by chemical inhibitor treatment or by genetic mutation. Exposing 4-day-old zebrafish larvae to 2% ethanol for 24 h induced hepatic steatosis, angiogenesis and fibrogenesis. The liver started self-repair once ethanol was removed. Although inhibiting Kdrl did not block the initial activation of hepatic stellate cells during ethanol treatment, it suppressed their proliferation, extracellular matrix protein deposition and fibrogenic gene expression after ethanol exposure, thus enhancing the liver repair. It also ameliorated hepatic steatosis and attenuated hepatic angiogenesis that accelerated after the ethanol treatment. qPCR showed that hepatic stellate cells are the first liver cell type to increase the expression of VEGF ligand and receptor genes in response to ethanol exposure. Both hepatic stellate cells and endothelial cells, but not hepatic parenchymal cells, expressed kdrl upon ethanol exposure and were likely the direct targets of Kdrl inhibition. Ethanol-induced steatosis and fibrogenesis still occurred in cloche mutants that have hepatic stellate cells but lack hepatic endothelial cells, and Kdrl inhibition suppressed both phenotypes in the mutants. These results suggest that VEGF signaling mediates interactions between activated hepatic stellate cells and hepatocytes that lead to steatosis. Our study demonstrates the involvement of VEGF signaling in regulating sustained liver injuries after acute alcohol exposure. It also provides a proof of principle of using the zebrafish model

  3. Lung endothelial barrier protection by iloprost in the two-hit models of VILI involves inhibition of Rho signaling

    PubMed Central

    Birukova, Anna A.; Fu, Panfeng; Xing, Junjie; Cokic, Ivan; Birukov, Konstantin G.

    2010-01-01

    Mechanical ventilation at high tidal volume may cause pulmonary capillary leakage and acute lung inflammation culminating in ventilator-induced lung injury. Iloprost is a stable synthetic analogue of prostaglandin I2 used for treatment of pulmonary hypertension, which also showed endothelium-dependent anti-edemagenic effects in the models of lung injury. To test the hypothesis that iloprost may attenuate lung inflammation and lung endothelial barrier disruption caused by pathologic lung distension and coagulation system component thrombin, we used cell and animal two-hit models of ventilator-induced lung injury. Mice received triple injection of iloprost (2 μg/kg, intravenous instillation) at 0, 40 and 80 min after onset of high tidal volume (HTV) mechanical ventilation (30 ml/kg, 4 hrs) combined with administration of thrombin receptor activating peptide 6 (TRAP6, 3 × 10−7 mol/mouse, intratracheal instillation). After 4 hrs of ventilation, bronchoalveolar lavage (BAL), histological analysis, and measurements of Evans blue accumulation in the lung tissue lung were performed. Effects of iloprost on endothelial barrier dysfunction were further assessed in pulmonary endothelial cells (EC) exposed to thrombin and pathologic (18%) cyclic stretch. Combination of HTV and TRAP6 enhanced accumulation of neutrophils in BAL fluid and lung parenchyma, increased BAL protein content and endothelial permeability judged by Evans blue extravasation in the lung tissue. These effects were markedly attenuated by iloprost. Application of 18% cyclic stretch to pulmonary EC enhanced thrombin-induced EC paracellular gap formation and Rho-GTPase-mediated phosphorylation of regulatory myosin light chains and myosin phosphatase. Iloprost markedly inhibited Rho-kinase mediated site-specific phosphorylation of myosin phosphatase, and prevented cyclic stretch- and thrombin-induced endothelial monolayer disruption. This study characterizes for the first time the protective effects of

  4. H2S inhibits pulmonary arterial endothelial cell inflammation in rats with monocrotaline-induced pulmonary hypertension.

    PubMed

    Feng, Shasha; Chen, Siyao; Yu, Wen; Zhang, Da; Zhang, Chunyu; Tang, Chaoshu; Du, Junbao; Jin, Hongfang

    2017-03-01

    This study aimed to determine whether hydrogen sulfide (H2S) inhibits pulmonary arterial endothelial inflammation in rats with monocrotaline (MCT)-induced pulmonary hypertension and its possible mechanisms. Twenty-four male Wistar rats were divided randomly into control, MCT, and MCT+H2S treatment groups. Human pulmonary arterial endothelial cells (HPAEC) were cultured and divided into four groups: control, MCT, MCT+H2S, and H2S. Pulmonary artery pressure was determined using a right cardiac catheterization procedure 3 weeks after MCT administration. Pulmonary vascular morphological changes and inflammatory infiltration were measured. Endogenous H2S levels, cystathionine-γ-lyase (CSE) expression, and inflammatory cytokines were determined both in vivo and in vitro. In addition, phosphorylation of NF-κB p65 and IκBα was detected by western blotting, and NF-κB p65 nuclear translocation, as well as its DNA-binding activity, was determined. Pulmonary hypertension and vascular remolding developed 3 wks after MCT administration, with elevated lung tissue inflammatory infiltration and cytokine level associated with activation of the NF-κB pathway, both in vivo and in vitro. However, the endogenous H2S/CSE pathway was downregulated in MCT rats. By contrast, an H2S donor markedly reduced pulmonary artery pressure, pulmonary vascular structural remolding, and increased lung inflammatory infiltration and cytokine levels of MCT-treated rats. Meanwhile, H2S reversed the activation of the NF-κB pathway successfully. The downregulated pulmonary arterial endothelial H2S/CSE pathway is involved in the pulmonary inflammatory response in MCT-treated pulmonary hypertensive rats. H2S attenuated endothelial inflammation by inhibiting the NF-κB pathway.

  5. Epigallocatechin-3-gallate inhibits VCAM-1 expression and apoptosis induction associated with LC3 expressions in TNFα-stimulated human endothelial cells.

    PubMed

    Yamagata, Kazuo; Xie, Yajie; Suzuki, Sayaka; Tagami, Motoki

    2015-04-15

    Tumor necrosis factor alpha (TNF-α) promotes the expression of adhesion molecules and induces endothelial dysfunction, a process that can lead to atherosclerosis. Green tea consumption can inhibit endothelial dysfunction and attenuate the development of arteriosclerosis. The purpose of this study was to examine whether epigallocatechin-3-gallate (EGCG) prevents TNF-α-dependent endothelial dysfunction. Here, we compared the regulatory effects of the green tea components EGCG and L-theanine against TNF-α-induced stimulation of adhesion molecule expression and apoptosis induction, which is associated with autophagy. Monocytic cell adhesion to human endothelial cells was measured using a fluorescently-labeled cell line, U-937. Caspase 3/7 activity was examined with a fluorescent probe and fluorescence microscopy. In addition, we analyzed the expression of several genes by RT-PCR. TNF-α-modulation of LC3 and VCAM1 protein levels were investigated by Western blot (WB). TNF-α induced adhesion of U937 cells to endothelial cells, and gene expression associated with adhesion molecules and apoptosis. On the other hand, EGCG and L-theanine inhibited TNF-α-induced adhesion of U937 cells to endothelial cells and inhibited increases in ICAM1, CCL2 and VCAM1 expression. Furthermore, EGCG and L-theanine inhibited TNF-α-induced apoptosis-related gene expression (e.g., CASP9), and caspase activity while inhibiting TNFα-induced VCAM1, LC3A and LC3B protein expression. Meanwhile, treatment of endothelial cells with autophagy inhibitor 3-methyladenine (3-MA) blocked EGCG-induced expression of CASP9. Together, these results indicate that EGCG can modulate TNF-α-induced monocytic cell adhesion, apoptosis and autophagy. We thus conclude that EGCG might be beneficial for inhibiting TNF-α-mediated human endothelial disorders by affecting LC3 expression-related processes. Copyright © 2015 Elsevier GmbH. All rights reserved.

  6. Morin, a Flavonoid from Moraceae, Inhibits Cancer Cell Adhesion to Endothelial Cells and EMT by Downregulating VCAM1 and Ncadherin.

    PubMed

    Lee, JeongHee; Jin, Hana; Lee, Won Sup; Nagappan, Arulkumar; Choi, Yung Hyun; Kim, Gon Sup; Jung, JinMyung; Ryu, Chung Ho; Shin, Sung Chul; Hong, Soon Chan; Kim, Hye Jung

    2016-01-01

    Morin, a flavonoid found in figs and other Moraceae species, displays a variety of biological actions, exerting antioxidant, antiinflammatory and anticarcinogenic effects. Here, we investigated the anticancer activity of morin focusing on antiadhesive influence. We performed experiments with MDAMB231 human breast cancer cells. Morin inhibited TNFinduced cancer cell adhesion to human umbilical vein endothelial cells (HUVECs) without showing any toxicity. It further inhibited the expression of VCAM1 on MDAMB231 cells as well as HUVECs. Morin also decreased the expression of Ncadherin on MDAMB231 cells. In addition, there was apparent antimetastatic activity in vivo. In conclusion, this study suggested that morin inhibits cancer cell adhesion to HUVECs by reducing VCAM1, and EMT by targeting Ncadherin, and that it features antimetastatic activity in vivo. Further investigation of possible antimetastatic activity of morin against human breast cancer cells is warranted.

  7. Endothelial Cells Inhibit the Angiotensin II Induced Phenotypic Modulation of Rat Vascular Adventitial Fibroblasts.

    PubMed

    Xu, Jia-Ying; Chang, Neng-Bin; Li, Tao; Jiang, Rui; Sun, Xiao-Lei; He, Yan-Zheng; Jiang, Jun

    2017-07-01

    The phenotypic modulation of vascular adventitial fibroblasts plays an important role in vascular remodeling. Evidence have shown that endothelial cells and adventitial fibroblasts interact under certain conditions. In this study, we investigated the influence of endothelial cells on the phenotypic modulation of adventitial fibroblasts. Endothelial cells and adventitial fibroblasts from rat thoracic aorta were cultivated in a co-culture system and adventitial fibroblasts were induced with angiotensin II (Ang II). Collagen I and alpha smooth muscle actin (α-SMA) expression and migration of adventitial fibroblasts were analyzed. Ang II upregulated the expression of collagen I and α-SMA and the migration of adventitial fibroblasts. Adventitial fibroblasts-endothelial cells co-culturing attenuated the effects of Ang II. Homocysteine-treated endothelial cells, which are functionally impaired, were less inhibitory of the phenotypic modulation of adventitial fibroblasts. Supplementation of endothelial cells with L-arginine (L-Arg) or 8-bromoguanosine 3',5'-cyclic monophosphate (8-BrcGMP) enhanced the trends, while with L-NG-nitroarginine methyl ester (L-NAME) or 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) the opposite effect was observed. Under the influence of Ang II, adventitial fibroblasts were prone to undergo phenotypic modulation, which was closely related to vascular remodeling. Our study showed that endothelial cells influenced fibroblast phenotypic transformation and such effect would be mediated through the nitric oxide (NO)/cGMP signaling pathway. J. Cell. Biochem. 118: 1921-1927, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. Omentin inhibits TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via ERK/NF-{kappa}B pathway

    SciTech Connect

    Zhong, Xia; Li, Xiaonan; Liu, Fuli; Tan, Hui; Shang, Deya

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Black-Right-Pointing-Pointer Omentin reduces expression of ICAM-1 and VCAM-1 induced by TNF-{alpha} in HUVECs. Black-Right-Pointing-Pointer Omentin inhibits TNF-{alpha}-induced ERK and NF-{kappa}B activation in HUVECs. Black-Right-Pointing-Pointer Omentin supreeses TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 via ERK/NF-{kappa}B pathway. -- Abstract: In the present study, we investigated whether omentin affected the expression of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-{alpha} (TNF-{alpha}) induced human umbilical vein endothelial cells (HUVECs). Our data showed that omentin decreased TNF-{alpha}-induced expression of ICAM-1 and VCAM-1 in HUVECs. In addition, omentin inhibited TNF-{alpha}-induced adhesion of THP-1 cells to HUVECs. Further, we found that omentin inhibited TNF-{alpha}-activated signal pathway of nuclear factor-{kappa}B (NF-{kappa}B) by preventing NF-{kappa}B inhibitory protein (I{kappa}B{alpha}) degradation and NF-{kappa}B/DNA binding activity. Omentin pretreatment significantly inhibited TNF-{alpha}-induced ERK activity and ERK phosphorylation in HUVECs. Pretreatment with PD98059 suppressed TNF-{alpha}-induced NF-{kappa}B activity. Omentin, NF-kB inhibitor (BAY11-7082) and ERK inhibitor (PD98059) reduced the up-regulation of ICAM-1 and VCAM-1 induced by TNF-{alpha}. These results suggest that omentin may inhibit TNF-{alpha}-induced expression of adhesion molecules in endothelial cells via blocking ERK/NF-{kappa}B pathway.

  9. A Complex Extracellular Sphingomyelinase of Pseudomonas aeruginosa Inhibits Angiogenesis by Selective Cytotoxicity to Endothelial Cells

    PubMed Central

    Vasil, Michael L.; Stonehouse, Martin J.; Vasil, Adriana I.; Wadsworth, Sandra J.; Goldfine, Howard; Bolcome, Robert E.; Chan, Joanne

    2009-01-01

    The hemolytic phospholipase C (PlcHR) expressed by Pseudomonas aeruginosa is the original member of a Phosphoesterase Superfamily, which includes phosphorylcholine-specific phospholipases C (PC-PLC) produced by frank and opportunistic pathogens. PlcHR, but not all its family members, is also a potent sphingomyelinase (SMase). Data presented herein indicate that picomolar (pM) concentrations of PlcHR are selectively lethal to endothelial cells (EC). An RGD motif of PlcHR contributes to this selectivity. Peptides containing an RGD motif (i.e., GRGDS), but not control peptides (i.e., GDGRS), block the effects of PlcHR on calcium signaling and cytotoxicity to EC. Moreover, RGD variants of PlcHR (e.g., RGE, KGD) are significantly reduced in their binding and toxicity, but retain the enzymatic activity of the wild type PlcHR. PlcHR also inhibits several EC-dependent in vitro assays (i.e., EC migration, EC invasion, and EC tubule formation), which represent key processes involved in angiogenesis (i.e., formation of new blood vessels from existing vasculature). Finally, the impact of PlcHR in an in vivo model of angiogenesis in transgenic zebrafish, and ones treated with an antisense morpholino to knock down a key blood cell regulator, were evaluated because in vitro assays cannot fully represent the complex processes of angiogenesis. As little as 2 ng/embryo of PlcHR was lethal to ∼50% of EGFP-labeled EC at 6 h after injection of embryos at 48 hpf (hours post-fertilization). An active site mutant of PlcHR (Thr178Ala) exhibited 120-fold reduced inhibitory activity in the EC invasion assay, and 20 ng/embryo elicited no detectable inhibitory activity in the zebrafish model. Taken together, these observations are pertinent to the distinctive vasculitis and poor wound healing associated with P. aeruginosa sepsis and suggest that the potent antiangiogenic properties of PlcHR are worthy of further investigation for the treatment of diseases where angiogenesis contributes

  10. Inhibition of Epidermal Growth Factor Receptor and Vascular Endothelial Growth Factor Receptor Phosphorylation on Tumor-Associated Endothelial Cells Leads to Treatment of Orthotopic Human Colon Cancer in Nude Mice1

    PubMed Central

    Sasaki, Takamitsu; Kitadai, Yasuhiko; Nakamura, Toru; Kim, Jang-Seong; Tsan, Rachel Z; Kuwai, Toshio; Langley, Robert R; Fan, Dominic; Kim, Sun-Jin; Fidler, Isaiah J

    2007-01-01

    The purpose of our study was to determine whether the dual inhibition of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor (VEGFR) signaling pathways in tumor-associated endothelial cells can inhibit the progressive growth of human colon carcinoma in the cecum of nude mice. SW620CE2 human colon cancer cells growing in culture and orthotopically in the cecum of nude mice expressed a high level of transforming growth factor alpha (TGF-α) and vascular endothelial growth factor (VEGF) but were negative for EGFR, human epidermal growth factor receptor 2 (HER2), and VEGFR. Double immunofluorescence staining revealed that tumor-associated endothelial cells expressed EGFR, VEGFR2, phosphorylated EGFR (pEGFR), and phosphorylated VEGFR (pVEGFR). Treatment of mice with either 7H-pyrrolo [2,3-d]-pyrimidine lead scaffold (AEE788; an inhibitor of EGFR and VEGFR tyrosine kinase) or CPT-11 as single agents significantly inhibited the growth of cecal tumors (P < .01); this decrease was even more pronounced with AEE788 combined with CPT-11 (P < .001). AEE788 alone or combined with CPT-11 also inhibited the expression of pEGFR and pVEGFR on tumor-associated endothelial cells, significantly decreased vascularization and tumor cell proliferation, and increased the level of apoptosis in both tumor-associated endothelial cells and tumor cells. These data demonstrate that targeting EGFR and VEGFR signaling on tumor-associated endothelial cells provides a viable approach for the treatment of colon cancer. PMID:18084614

  11. H2 inhibits TNF-α-induced lectin-like oxidized LDL receptor-1 expression by inhibiting nuclear factor κB activation in endothelial cells.

    PubMed

    Song, Guohua; Tian, Hua; Liu, Jia; Zhang, Hongle; Sun, Xuejun; Qin, Shucun

    2011-09-01

    H(2) is a therapeutic antioxidant that can reduce oxidative stress. Oxidized low-density lipoprotein, which plays roles in atherosclerosis, may promote endothelial dysfunction by binding the cell-surface receptor LOX-1. LOX-1 expression can be upregulated by various stimuli, including TNF-α. Thus, we aimed to examine whether the upregulation of LOX-1 by different stimuli could be blocked by H(2) in endothelial cells. H(2) significantly abolished the upregulation of LOX-1 by different stimuli, including TNF-α, at the protein and mRNA levels. The TNF-α-induced upregulation of LOX-1 was also attenuated by the NF-κB inhibitor N-acetyl-L-cysteine. H(2) inhibited the TNF-α-induced activation of NF-κB and the phosphorylation of IκB-α. Furthermore, H(2) inhibited the expression of LOX-1 and the activation of NF-κB in apolipoprotein E knockout mice, an animal model of atherosclerosis. Thus, H(2) probably inhibits cytokine-induced LOX-1 gene expression by suppressing NF-κB activation.

  12. Inhibition of GAPDH activity by poly(ADP-ribose) polymerase activates three major pathways of hyperglycemic damage in endothelial cells

    PubMed Central

    Du, Xueliang; Matsumura, Takeshi; Edelstein, Diane; Rossetti, Luciano; Zsengellér, Zsuzsanna; Szabó, Csaba; Brownlee, Michael

    2003-01-01

    In this report, we show that hyperglycemia-induced overproduction of superoxide by the mitochondrial electron transport chain activates the three major pathways of hyperglycemic damage found in aortic endothelial cells by inhibiting GAPDH activity. In bovine aortic endothelial cells, GAPDH antisense oligonucleotides activated each of the pathways of hyperglycemic vascular damage in cells cultured in 5 mM glucose to the same extent as that induced by culturing cells in 30 mM glucose. Hyperglycemia-induced GAPDH inhibition was found to be a consequence of poly(ADP-ribosyl)ation of GAPDH by poly(ADP-ribose) polymerase (PARP), which was activated by DNA strand breaks produced by mitochondrial superoxide overproduction. Both the hyperglycemia-induced decrease in activity of GAPDH and its poly(ADP-ribosyl)ation were prevented by overexpression of either uncoupling protein–1 (UCP-1) or manganese superoxide dismutase (MnSOD), which decrease hyperglycemia-induced superoxide. Overexpression of UCP-1 or MnSOD also prevented hyperglycemia-induced DNA strand breaks and activation of PARP. Hyperglycemia-induced activation of each of the pathways of vascular damage was abolished by blocking PARP activity with the competitive PARP inhibitors PJ34 or INO-1001. Elevated glucose increased poly(ADP-ribosyl)ation of GAPDH in WT aortae, but not in the aortae from PARP-1–deficient mice. Thus, inhibition of PARP blocks hyperglycemia-induced activation of multiple pathways of vascular damage. PMID:14523042

  13. Phloroglucinol Inhibits the Bioactivities of Endothelial Progenitor Cells and Suppresses Tumor Angiogenesis in LLC-Tumor-Bearing Mice

    PubMed Central

    Kwon, Yi-Hong; Jung, Seok-Yun; Kim, Jae-Won; Lee, Sang-Hun; Lee, Jun-Hee; Lee, Boo-Yong; Kwon, Sang-Mo

    2012-01-01

    Background There is increasing evidence that phloroglucinol, a compound from Ecklonia cava, induces the apoptosis of cancer cells, eventually suppressing tumor angiogenesis. Methodology/Principal Findings This is the first report on phloroglucinol's ability to potentially inhibit the functional bioactivities of endothelial progenitor cells (EPCs) and thereby attenuate tumor growth and angiogenesis in the Lewis lung carcinoma (LLC)-tumor-bearing mouse model. Although Phloroglucinol did not affect their cell toxicity, it specifically inhibited vascular endothelial growth factor (VEGF) dependent migration and capillary-like tube formation of EPCs. Our matrigel plug assay clearly indicated that orally injected phloroglucinol effectively disrupts VEGF-induced neovessel formation. Moreover, we demonstrated that when phloroglucinol is orally administered, it significantly inhibits tumor growth and angiogenesis as well as CD45−/CD34+ progenitor mobilization into peripheral blood in vivo in the LLC-tumor-bearing mouse model. Conclusions/Significance These results suggest a novel role for phloroglucinol: Phloroglucinol might be a modulator of circulating EPC bioactivities, eventually suppressing tumorigenesis. Therefore, phloroglucinol might be a candidate compound for biosafe drugs that target tumor angiogenesis. PMID:22496756

  14. Inhibition of tumor necrosis factor-{alpha}-induced expression of adhesion molecules in human endothelial cells by the saponins derived from roots of Platycodon grandiflorum

    SciTech Connect

    Kim, Ji Young; Kim, Dong Hee; Kim, Hyung Gyun; Song, Gyu-Yong; Chung, Young Chul; Roh, Seong Hwan; Jeong, Hye Gwang . E-mail: hgjeong@chosun.ac.kr

    2006-01-15

    Adhesion molecules play an important role in the development of atherogenesis and are produced by endothelial cells after being stimulated with various inflammatory cytokines. This study examined the effect of saponins that were isolated from the roots of Platycodon grandiflorum A. DC (Campanulaceae), Changkil saponins (CKS), on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. CKS significantly inhibited the TNF{alpha}-induced increase in monocyte adhesion to endothelial cells as well as decreased the protein and mRNA expression levels of vascular adhesion molecule-1 and intercellular cell adhesion molecule-1 on endothelial cells. Furthermore, CKS significantly inhibited the TNF{alpha}-induced production of intracellular reactive oxygen species (ROS) and activation of NF-{kappa}B by preventing I{kappa}B degradation and inhibiting I{kappa}B kinase activity. Overall, CKS has anti-atherosclerotic and anti-inflammatory activity, which is least in part the result of it reducing the cytokine-induced endothelial adhesion to monocytes by inhibiting intracellular ROS production, NF-{kappa}B activation, and cell adhesion molecule expression in endothelial cells.

  15. Vascular endothelial growth factor expression and inhibition in uveal melanoma cell lines

    PubMed Central

    Logan, Patrick; Burnier, Julia; Burnier, Miguel N.

    2013-01-01

    Background: Uveal melanoma (UM) is a disease that affects approximately five people per million in the United States. This disease metastasises predominantly to the liver, and treatment options following the clinical detection of these sequelae are limited. Vascular endothelial growth factor-A (VEGF-A) is the primary activator of tumour angiogenesis and functions by binding to VEGF-Receptor 2 (VEGF-R2) and is often required for tumour growth beyond 2–3 mm. The purpose of this study was to investigate the expression of VEGF-A and the primary VEGF-R2 in three UM cell lines. Furthermore, we investigated the effects of VEGF-A inhibition on receptor activation and production of other cytokines. Finally, the effects of VEGF-A inhibition on the proliferation, migration, and invasion in the cell lines were ascertained. Materials: Three UM cell lines (92.1, OCM-1, and UW-1) were incubated with and without the addition of 100 μg/mL of bevacizumab. VEGF-A expression under both conditions was determined by sandwich enzyme-linked immunosorbent assay (ELISA), and phosphorylated VEGF-R2 expression was determined using western blot. The effects of VEGF-A inhibition on 20 cytokines (IL-1a, IL-2, IL-5, IL-8, IL-12p70, GM-CSF, IFNy, CCL3, MMP-9, TNF-a, IL-1b, IL-4, IL-6, IL-10, IL-13, GRO, MCP-1, MIP-1b, and RANTES) were determined using a multiplex sandwich ELISA. Proliferation rates before and after treatment were evaluated via sulforhodamine B assay, and migration and invasion assays implementing the Boyden chamber technique, the latter with artificial extracellular matrix, were used to assess their respective abilities. The Student’s t-test was used to compare changes in cytokine expression following VEGF-A inhibition. Analysis of variance was used to compare changes in the functional abilities of three uveal melanoma cell lines following VEGF-A inhibition. A P-value < 0.05 was considered statistically significant. Results: All three cell lines produced copious amounts of

  16. Stat3 orchestrates interaction between endothelial and tumor cells and inhibition of Stat3 suppresses brain metastasis of breast cancer cells

    PubMed Central

    Chou, Ping-Chieh; Zhou, Aidong; Yang, Phillip; Conrad, Charles A.; Aldape, Kenneth D.; Priebe, Waldemar; Patterson, Cam; Sawaya, Raymond; Xie, Keping; Huang, Suyun

    2015-01-01

    Brain metastasis is a major cause of morbidity and mortality in patients with breast cancer. Our previous studies indicated that Stat3 plays an important role in brain metastasis. Here, we present evidence that Stat3 functions at the level of the microenvironment of brain metastases. Stat3 controlled constitutive and inducible VEGFR2 expression in tumor-associated brain endothelial cells. Furthermore, inhibition of Stat3 by WP1066 decreased the incidence of brain metastases and increased survival in a preclinical model of breast cancer brain metastasis. WP1066 inhibited Stat3 activation in tumor-associated endothelial cells, reducing their infiltration and angiogenesis. WP1066 also inhibited breast cancer cell invasion. Our results indicate that WP1066 can inhibit tumor angiogenesis and brain metastasis mediated by Stat3 in endothelial and tumor cells. PMID:25881542

  17. Stat3 orchestrates interaction between endothelial and tumor cells and inhibition of Stat3 suppresses brain metastasis of breast cancer cells.

    PubMed

    Lee, Hsueh-Te; Xue, Jianfei; Chou, Ping-Chieh; Zhou, Aidong; Yang, Phillip; Conrad, Charles A; Aldape, Kenneth D; Priebe, Waldemar; Patterson, Cam; Sawaya, Raymond; Xie, Keping; Huang, Suyun

    2015-04-30

    Brain metastasis is a major cause of morbidity and mortality in patients with breast cancer. Our previous studies indicated that Stat3 plays an important role in brain metastasis. Here, we present evidence that Stat3 functions at the level of the microenvironment of brain metastases. Stat3 controlled constitutive and inducible VEGFR2 expression in tumor-associated brain endothelial cells. Furthermore, inhibition of Stat3 by WP1066 decreased the incidence of brain metastases and increased survival in a preclinical model of breast cancer brain metastasis. WP1066 inhibited Stat3 activation in tumor-associated endothelial cells, reducing their infiltration and angiogenesis. WP1066 also inhibited breast cancer cell invasion. Our results indicate that WP1066 can inhibit tumor angiogenesis and brain metastasis mediated by Stat3 in endothelial and tumor cells.

  18. Diacerein inhibits the pro-atherogenic & pro-inflammatory effects of IL-1 on human keratinocytes & endothelial cells

    PubMed Central

    Bao, Lei; Many, Benjamin; Chan, Lawrence S.

    2017-01-01

    We investigated IL-1-induced regulation of genes related to inflammation and atherogenesis in human keratinocytes and endothelial cells, and if ‘diacerein’, an oral IL-1 inhibiting drug currently approved for use in osteoarthritis, would reverse IL-1’s effects on these cells. Primary human keratinocytes and coronary artery endothelial cells were treated with either IL-1α or IL-1β, with and without diacerein. Using PCR-array, we assessed differential gene-expression regulated by IL-1 and diacerein. We identified 34 pro-atherogenic genes in endothelial cells and 68 pro-inflammatory genes in keratinocytes significantly (p<0.05) regulated at least 2-fold by IL-1, in comparison to control. Diacerein completely or partially reversed this regulation on almost all genes. Using ELISA, we confirmed diacerein’s ability to reverse IL-1-driven gene-regulation of 11 selected factors, at the protein level. The results support a novel idea that diacerein acts as an inhibitor of the pro-atherogenic and pro-inflammatory effects of IL-1. Diacerein may have therapeutic applications to diminish IL-1-induced skin inflammation in psoriasis and attenuate IL-1-induced development of atherosclerosis. Further investigation into diacerein’s effect on skin inflammation, atherogenesis and cardiovascular risk in animal models or humans is warranted. PMID:28323859

  19. Rocuronium Bromide Inhibits Inflammation and Pain by Suppressing Nitric Oxide Production and Enhancing Prostaglandin E2 Synthesis in Endothelial Cells

    PubMed Central

    2016-01-01

    Purpose Rocuronium bromide is a nondepolarizing neuromuscular blocking drug and has been used as an adjunct for relaxation or paralysis of the skeletal muscles, facilitation of endotracheal intubation, and improving surgical conditions during general anesthesia. However, intravenous injection of rocuronium bromide induces injection pain or withdrawal movement. The exact mechanism of rocuronium bromide-induced injection pain or withdrawal movement is not yet understood. We investigated whether rocuronium bromide treatment is involved in the induction of inflammation and pain in vascular endothelial cells. Methods For this study, calf pulmonary artery endothelial (CPAE) cells were used, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Western blot, nitric oxide detection, and prostaglandin E2 immunoassay were conducted. Results Rocuronium bromide treatment inhibited endothelial nitric oxide synthase and suppressed nitric oxide production in CPAE cells. Rocuronium bromide activated cyclooxygenase-2, inducible nitric oxide synthase and increased prostaglandin E2 synthesis in CPAE cells. Conclusions Rocuronium bromide induced inflammation and pain in CPAE cells. Suppressing nitric oxide production and enhancing prostaglandin E2 synthesis might be associated with rocuronium bromide-induced injection pain or withdrawal movement. PMID:28043117

  20. Inhibitive Effects of Mulberry Leaf-Related Extracts on Cell Adhesion and Inflammatory Response in Human Aortic Endothelial Cells

    PubMed Central

    Chao, P.-Y.; Lin, K.-H.; Chiu, C.-C.; Yang, Y.-Y.; Huang, M.-Y.; Yang, C.-M.

    2013-01-01

    Effects of mulberry leaf-related extracts (MLREs) on hydrogen peroxide-induced DNA damage in human lymphocytes and on inflammatory signaling pathways in human aortic endothelial cells (HAECs) were studied. The tested MLREs were rich in flavonols, especially bombyx faces tea (BT) in quercetin and kaempferol. Polyphenols, flavonoids, and anthocyanidin also abounded in BT. The best trolox equivalent antioxidant capacity (TEAC) was generated from the acidic methanolic extracts of BT. Acidic methanolic and water extracts of mulberry leaf tea (MT), mulberry leaf (M), and BT significantly inhibited DNA oxidative damage to lymphocytes based on the comet assay as compared to the H2O2-treated group. TNF-α-induced monocyte-endothelial cell adhesion was significantly suppressed by MLREs. Additionally, nuclear factor kappa B (NF-κB) expression was significantly reduced by BT and MT. Significant reductions were also observed in both NF-κB and activator protein (AP)-1 DNA binding by MLREs. Significant increases in peroxisome proliferator-activated receptor (PPAR) α and γ DNA binding by MLREs were also detected in M and MT extracts, but no evidence for PPAR α DNA binding in 50 μg/mL MT extract was found. Apparently, MLREs can provide distinct cytoprotective mechanisms that may contribute to its putative beneficial effects on suppressing endothelial responses to cytokines during inflammation. PMID:24371453

  1. S-nitrosylation of Hsp90 promotes the inhibition of its ATPase and endothelial nitric oxide synthase regulatory activities

    PubMed Central

    Martínez-Ruiz, Antonio; Villanueva, Laura; de Orduña, Cecilia González; López-Ferrer, Daniel; Higueras, María Ángeles; Tarín, Carlos; Rodríguez-Crespo, Ignacio; Vázquez, Jesús; Lamas, Santiago

    2005-01-01

    Nitric oxide is implicated in a variety of signaling pathways in different systems, notably in endothelial cells. Some of its effects can be exerted through covalent modifications of proteins and, among these modifications, increasing attention is being paid to S-nitrosylation as a signaling mechanism. In this work, we show by a variety of methods (ozone chemiluminescence, biotin switch, and mass spectrometry) that the molecular chaperone Hsp90 is a target of S-nitrosylation and identify a susceptible cysteine residue in the region of the C-terminal domain that interacts with endothelial nitric oxide synthase (eNOS). We also show that the modification occurs in endothelial cells when they are treated with S-nitroso-l-cysteine and when they are exposed to eNOS activators. Hsp90 ATPase activity and its positive effect on eNOS activity are both inhibited by S-nitrosylation. Together, these data suggest that S-nitrosylation may functionally regulate the general activities of Hsp90 and provide a feedback mechanism for limiting eNOS activation. PMID:15937123

  2. H2S Inhibits Oscillatory Shear Stress-Induced Monocyte Binding to Endothelial Cells Via Nitric Oxide Production

    PubMed Central

    Go, Young-Mi; Lee, Hye-Rim; Park, Heonyong

    2012-01-01

    H2S is a signaling molecule associated with protection against vascular diseases, including atherosclerosis. This protection involves the stimulation of vasorelaxation, but other possible contributing mechanisms have not been extensively explored. In this study, we found that the vascular H2S-producing enzyme, cystathionine-γ-lyase (CSE), was down-regulated by oscillatory shear stress (OSS) among various vaso-regulators. Consistently, NaHS, an H2S donor, appeared to inhibit OSS-induced THP-1 cell adhesion. We also found that NaHS activated the nitric oxide (NO)-producing Akt/endothelial nitric oxide synthase (eNOS) signaling pathway in response to OSS, whereas NaHS had no effect on IκB, a well-known molecule regulating pro-inflammatory signaling pathways. Moreover, NaHS increased OSS-dependent eNOS expression and decreased expression of intercellular adhesion molecule-1 (ICAM-1). NG-nitro-L-arginine methyl ester (L-NAME), an eNOS inhibitor, abrogated the inhibitory effects of NaHS on OSS-induced endothelial ICAM-1 expression and monocyte adhesion to endothelial cells. These data suggest that down-regulation of CSE resulting in decreased levels of H2S is a key factor for OSS-associated atherogenesis and further suggest that regulation of H2S production can be a potential target for preventing cardiovascular diseases. PMID:23124382

  3. Activation of Nrf2/ARE pathway protects endothelial cells from oxidant injury and inhibits inflammatory gene expression.

    PubMed

    Chen, Xi-Lin; Dodd, Geraldine; Thomas, Suzanne; Zhang, Xiaolan; Wasserman, Martin A; Rovin, Brad H; Kunsch, Charles

    2006-05-01

    The antioxidant response element (ARE) is a transcriptional control element that mediates expression of a set of antioxidant proteins. NF-E2-related factor 2 (Nrf2) is a transcription factor that activates ARE-containing genes. In endothelial cells, the ARE-mediated genes are upregulated by atheroprotective laminar flow through a Nrf2-dependent mechanism. We tested the hypothesis that activation of ARE-regulated genes via adenovirus-mediated expression of Nrf2 may suppress redox-sensitive inflammatory gene expression. Expression of Nrf2 in human aortic endothelial cells (HAECs) resulted in a marked increase in ARE-driven transcriptional activity and protected HAECs from H2O2-mediated cytotoxicity. Nrf2 suppressed TNF-alpha-induced monocyte chemoattractant protein (MCP)-1 and VCAM-1 mRNA and protein expression in a dose-dependent manner and inhibited TNF-alpha-induced monocytic U937 cell adhesion to HAECs. Nrf2 also inhibited IL-1beta-induced MCP-1 gene expression in human mesangial cells. Expression of Nrf2 inhibited TNF-alpha-induced activation of p38 MAP kinase. Furthermore, expression of a constitutively active form of MKK6 (an upstream kinase for p38 MAP kinase) partially reversed Nrf2-mediated inhibition of VCAM-1 expression, suggesting that p38 MAP kinase, at least in part, mediates Nrf2's anti-inflammatory action. In contrast, Nrf2 did not inhibit TNF-alpha-induced NF-kappaB activation. These data identify the Nrf2/ARE pathway as an endogenous atheroprotective system for antioxidant protection and suppression of redox-sensitive inflammatory genes, suggesting that targeting the Nrf2/ARE pathway may represent a novel therapeutic approach for the treatment of inflammatory diseases such as atherosclerosis.

  4. Milk-derived bioactive peptides inhibit human endothelial-monocyte interactions via PPAR-γ dependent regulation of NF-κB.

    PubMed

    Marcone, Simone; Haughton, Karen; Simpson, Paul J; Belton, Orina; Fitzgerald, Desmond J

    2015-01-01

    Milk-derived bioactive peptides retain many biological properties and have therapeutic effects in cardiovascular disorders such as atherosclerosis. Under inflammatory conditions the expression of endothelial cells adhesion molecules is induced, increasing monocyte adhesion to human vessel wall, a critical step in the pathogenesis of atherosclerosis. In the present work we explored the effects of milk-derived bioactive peptides on the expression of the inflammatory phenotype of human endothelial cells and their effects on monocyte adherence to endothelial cells. Treatment of endothelial cells with milk-derived hydrolysate inhibited their production of inflammatory proteins MCP-1 and IL-8 and expression of VCAM-1, ICAM-1 and E-selectin. Milk derived hydrolysate also attenuated the adhesion of human monocytes to activated endothelial cells. The effect was similar to that obtained in endothelial cells treated with troglitazone, a ligand of peroxisome proliferators-activator receptor-gamma (PPAR-γ). PPAR-γ is a transcription factor which when activated antagonises the pro-inflammatory capability of nuclear factor κB (NF-κB). We further examined whether the effects of milk-derived hydrolysates on endothelial cells may be mediated through NF-κB activation via a PPAR-γ dependent mechanism. The specific PPAR-γ inhibitor, GW9662 blocked the effects of the hydrolysate on the NF-κB-mediated chemokines and adhesion molecules expression in endothelial cells. These results suggest that milk-derived bioactive peptides work as anti-atherogenic agents through the inhibition of endothelial-dependent adhesive interactions with monocytes by inhibiting the NF-κB pathway through a PPAR-γ dependent mechanism.

  5. Androgens inhibit tumor necrosis factor-α-induced cell adhesion and promote tube formation of human coronary artery endothelial cells.

    PubMed

    Liao, Chun-Hou; Lin, Feng-Yen; Wu, Yi-No; Chiang, Han-Sun

    2012-06-01

    Endothelial cells contribute to the function and integrity of the vascular wall, and a functional aberration may lead to atherogenesis. There is increasing evidence on the atheroprotective role of androgens. Therefore, we studied the effect of the androgens-testosterone and dihydrotestosterone-and estradiol on human coronary artery endothelial cell (HCAEC) function. We found by MTT assay that testosterone is not cytotoxic and enhances HCAEC proliferation. The effect of testosterone (10-50 nM), dihydrotestosterone (5-50 nM), and estradiol (0.1-0.4 nM) on the adhesion of tumor necrosis factor-α (TNF-α)-stimulated HCAECs was determined at different time points (12-96 h) by assessing their binding with human monocytic THP-1 cells. In addition, the expression of adhesion molecules, vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1), was determined by ELISA and Western blot analysis. Both testosterone and dihydrotestosterone attenuated cell adhesion and the expression of VCAM-1 and ICAM-1 in a dose- and time-dependent manner. Furthermore, androgen treatment for a longer duration inhibited cell migration, as demonstrated by wound-healing assay, and promoted tube formation on a Matrigel. Western blot analysis demonstrated that the expression of phosphorylated endothelial nitric oxide synthase (eNOS) increased, whereas that of inducible nitric oxide synthase (iNOS) decreased following the 96-h steroid treatment of TNF-α-stimulated HCAECs. Our findings suggest that androgens modulate endothelial cell functions by suppressing the inflammatory process and enhancing wound-healing and regenerative angiogenesis, possibly through an androgen receptor (AR)-dependent mechanism.

  6. Oligo-guanosine nucleotide induces neuropilin-1 internalization in endothelial cells and inhibits angiogenesis

    PubMed Central

    Narazaki, Masashi; Segarra, Marta; Hou, Xu; Tanaka, Toshio; Li, Xuri

    2010-01-01

    Ligand interaction with cognate cell-surface receptor often promotes receptor internalization, protecting cells from prolonged or excessive signaling from extracellular ligands. Compounds that induce internalization of surface receptors prevent ligand binding to cognate cell-surface receptors serving as inhibitors. Here, we show that synthetic polyriboguanosine (poly G) and oligo-deoxyriboguanosine (oligo G) reduce endothelial levels of surface neuropilin-1 (NRP1), a receptor shared by semaphorin 3A and vascular endothelial growth factor (VEGF), which plays critical roles in angiogenesis. Oligo G also reduces levels of cell-surface scavenger receptor expressed by endothelial cells I (SREC-I), but not levels of NRP2, gp130, CD31, VEGFR-1, or VEGFR-2. Poly or oligo A, T, and C do not promote NRP1 or SREC-I internalization. We find that oligo G binds to NRP1 with high affinity (Kd:1.3 ± 0.16nM), bridges the extracellular domain of NRP1 to that of SREC-I, and induces coordinate internalization of NRP1 and SREC-I. In vitro, oligo G blocks the binding and function of VEGF165 in endothelial cells. In vivo, intravitreal administration of oligo G reduces choroidal neovascularization in mice. These results demonstrate that synthetic oligo G is an inhibitor of pathologic angiogenenesis that reduces cell-surface levels and function of NRP1 acting as an internalization inducer. PMID:20606164

  7. Soy diet inhibits expression of inflammation-induced vascular cell adhesion molecules in endothelial cells

    USDA-ARS?s Scientific Manuscript database

    Recently we reported that dietary soy attenuated atherogenesis in apolipoprotein E knockout (apoE-/-) mice. However, the molecular mechanisms contributing to the atheroprotective effect of soy-based diets is not clear. Since interactions between endothelial cells and monocytes play a pivotal role ...

  8. Silencing heme oxygenase-1 gene expression in retinal pigment epithelial cells inhibits proliferation, migration and tube formation of cocultured endothelial cells

    SciTech Connect

    Zhang, Wenjie; Zhang, Xiaomei; Lu, Hong; Matsukura, Makoto; Zhao, Jien; Shinohara, Makoto

    2013-05-10

    Highlights: •HO-1 is highly induced in RPE cells by hypoxia. •Inhibition of HO-1 activity and knockdown of HO-1 expression inhibit VEGF expression in RPE cells under hypoxia. •Knockdown of HO-1 in RPE cells inhibits angiogenesis of endothelial cells in vitro. -- Abstract: Heme oxygenase-1 (HO-1) plays an important role in the vasculature and in the angiogenesis of tumors, wounds and other environments. Retinal pigment epithelial (RPE) cells and choroidal endothelial cells (CECs) are the main cells involved in choroidal neovascularization (CNV), a process in which hypoxia plays an important role. Our aim was to evaluate the role of human RPE-cell HO-1 in the angiogenic activities of cocultured endothelial cells under hypoxia. Small interfering RNA (siRNA) for HO-1 was transfected into human RPE cell line ARPE-19, and zinc protoporphyrin (ZnPP) was used to inhibit HO-1 activity. Knockdown of HO-1 expression and inhibition of HO-1 activity resulted in potent reduction of the expression of vascular endothelial growth factor (VEGF) under hypoxia. Furthermore, knockdown of HO-1 suppressed the proliferation, migration and tube formation of cocultured endothelial cells. These findings indicated that HO-1 might have an angiogenic effect in CNV through modulation of VEGF expression and might be a potential target for treating CNV.

  9. Chronic Inhibition of PPAR-γ Signaling Induces Endothelial Dysfunction In The Juvenile Lamb

    PubMed Central

    Sharma, Shruti; Barton, Jubilee; Rafikov, Ruslan; Aggarwal, Saurabh; Kuo, Hsuan-Chang; Oishi, Peter E.; Datar, Sanjeev A.; Fineman, Jeffrey R; Black, Stephen M.

    2013-01-01

    We have recently shown that the development of endothelial dysfunction in lambs with increased pulmonary blood flow (PBF) correlates with a decrease in peroxisome proliferator activated receptor-γ (PPAR-γ) signaling. Thus, in this study we determined if the loss of PPAR-γ signaling is necessary and sufficient to induce endothelial dysfunction by exposing lambs with normal PBF to the PPAR-γ antagonist, GW9662. Two-weeks of exposure to GW9662 significantly decreased both PPAR-γ protein and activity. In addition, although eNOS protein and nitric oxide metabolites (NOx) were significantly increased, endothelial dependent pulmonary vasodilation in response to acetylcholine was attenuated, indicative of endothelial dysfunction. To elucidate whether downstream mediators of vasodilation were impaired we examined soluble guanylate cyclase (sGC)- α and β subunit protein, cGMP levels, and phosphodiesterase 5 (PDE5) protein and activity, but we found no significant changes. However, we found that peroxynitrite levels were significantly increased in GW9662-treated lambs and this correlated with a significant increase in protein kinase G-1α (PKG-1α) nitration and a reduction in PKG activity. Peroxynitrite is formed by the interaction of NO with superoxide and we found that there was a significant increase in superoxide generation in GW9662-treated lambs. Further, we identified dysfunctional mitochondria as the primary source of the increased superoxide. Finally, we found that the mitochondrial dysfunction was due to a disruption in carnitine metabolism. We conclude that loss of PPAR-γ signaling is sufficient to induce endothelial dysfunction confirming its important role in maintaining a healthy vasculature. PMID:23257346

  10. Asiatic Acid Inhibits Pro-Angiogenic Effects of VEGF and Human Gliomas in Endothelial Cell Culture Models

    PubMed Central

    Kavitha, Chandagirikoppal V.; Agarwal, Chapla; Agarwal, Rajesh; Deep, Gagan

    2011-01-01

    Malignant gliomas are one of the most devastating and incurable tumors. Sustained excessive angiogenesis by glioma cells is the major reason for their uncontrolled growth and resistance toward conventional therapies resulting in high mortality. Therefore, targeting angiogenesis should be a logical strategy to prevent or control glioma cell growth. Earlier studies have shown that Asiatic Acid (AsA), a pentacyclic triterpenoid, is effective against glioma and other cancer cells; however, its efficacy against angiogenesis remains unknown. In the present study, we examined the anti-angiogenic efficacy of AsA using human umbilical vein endothelial cells (HUVEC) and human brain microvascular endothelial cells (HBMEC). Our results showed that AsA (5–20 µM) inhibits HUVEC growth and induces apoptotic cell death by activating caspases (3 and 9) and modulating the expression of apoptosis regulators Bad, survivin and pAkt-ser473. Further, AsA showed a dose-dependent inhibition of HUVEC migration, invasion and capillary tube formation, and disintegrated preformed capillary network. AsA also inhibited the VEGF-stimulated growth and capillary tube formation by HUVEC and HBMEC. Next, we analyzed the angiogenic potential of conditioned media collected from human glioma LN18 and U87-MG cells treated with either DMSO (control conditioned media, CCM) or AsA 20 µM (AsA20 conditioned media, AsA20CM). CCM from glioma cells significantly enhanced the capillary tube formation in both HUVEC and HBMEC, while capillary tube formation in both endothelial cell lines was greatly compromised in the presence of AsA20CM. Consistent with these results, VEGF expression was lesser in AsA20CM compared to CCM, and indeed AsA strongly inhibited VEGF level (both cellular and secreted) in glioma cells. AsA also showed dose-dependent anti-angiogenic efficacy in Matrigel plug assay, and inhibited the glioma cells potential to attract HUVEC/HBMEC. Overall, the present study clearly showed the strong anti

  11. IGFBP-3 inhibits TNF-α production and TNFR-2 signaling to protect against retinal endothelial cell apoptosis.

    PubMed

    Zhang, Qiuhua; Steinle, Jena J

    2014-09-01

    In models of diabetic retinopathy, insulin-like growth factor binding protein-3 (IGFBP-3) protects against tumor necrosis factors-alpha (TNF-α)-mediated apoptosis of retinal microvascular endothelial cells (REC), but the underlying mechanisms are unclear. Our current findings suggest that at least two discrete but complimentary pathways contribute to the protective effects of IGFBP-3; 1) IGFBP-3 directly activates the c-Jun kinase/tissue inhibitor of metalloproteinase-3/TNF-α converting enzyme (c-Jun/TIMP-3/TACE), pathway, which in turn inhibits TNF-α production; 2) IGFBP-3 acts through the IGFBP-3 receptor, low-density lipoprotein receptor-related protein 1 (LRP1), to inhibit signaling of TNF-α receptor 2 (TNFR2). Combined, these two IGFBP-3 pathways substantially reduce REC apoptosis and offer potential targets for the treatment of diabetic retinopathy.

  12. Cryptotanshinone inhibits TNF-α-induced LOX-1 expression by suppressing reactive oxygen species (ROS) formation in endothelial cells

    PubMed Central

    Ran, Xiaoli; Zhao, Wenwen; Li, Wenping

    2016-01-01

    Cryptotanshinone (CPT) is a natural compound isolated from traditional Chinese medicine Salvia miltiorrhiza Bunge. In the present study, the regulatory effect and potential mechanisms of CPT on tumor necrosis factor alpha (TNF-α) induced lectin-like receptor for oxidized low density lipoprotein (LOX-1) were investigated. Human umbilical vein endothelial cells (HUVECs) were cultured and the effect of TNF-α on LOX-1 expression at mRNA and protein levels was determined by Real-time PCR and Western blotting respectively. The formation of intracellular ROS was determined with fluorescence probe CM-DCFH2-DA. The endothelial ox-LDL uptake was evaluated with DiI-ox-LDL. The effect of CPT on LOX-1 expression was also evaluated with SD rats. TNF-α induced LOX-1 expression in a dose- and time-dependent manner in endothelial cells. TNF-α induced ROS formation, phosphorylation of NF-κB p65 and ERK, and LOX-1 expression, which were suppressed by rotenone, DPI, NAC, and CPT. NF-κB inhibitor BAY11-7082 and ERK inhibitor PD98059 inhibited TNF-α-induced LOX-1 expression. CPT and NAC suppressed TNF-α-induced LOX-1 expression and phosphorylation of NF-κB p65 and ERK in rat aorta. These data suggested that TNF-α induced LOX-1 expression via ROS activated NF-κB/ERK pathway, which could be inhibited by CPT. This study provides new insights for the anti-atherosclerotic effect of CPT. PMID:27382351

  13. Cryptotanshinone inhibits TNF-α-induced LOX-1 expression by suppressing reactive oxygen species (ROS) formation in endothelial cells.

    PubMed

    Ran, Xiaoli; Zhao, Wenwen; Li, Wenping; Shi, Jingshan; Chen, Xiuping

    2016-07-01

    Cryptotanshinone (CPT) is a natural compound isolated from traditional Chinese medicine Salvia miltiorrhiza Bunge. In the present study, the regulatory effect and potential mechanisms of CPT on tumor necrosis factor alpha (TNF-α) induced lectin-like receptor for oxidized low density lipoprotein (LOX-1) were investigated. Human umbilical vein endothelial cells (HUVECs) were cultured and the effect of TNF-α on LOX-1 expression at mRNA and protein levels was determined by Real-time PCR and Western blotting respectively. The formation of intracellular ROS was determined with fluorescence probe CM-DCFH2-DA. The endothelial ox-LDL uptake was evaluated with DiI-ox-LDL. The effect of CPT on LOX-1 expression was also evaluated with SD rats. TNF-α induced LOX-1 expression in a dose- and time-dependent manner in endothelial cells. TNF-α induced ROS formation, phosphorylation of NF-κB p65 and ERK, and LOX-1 expression, which were suppressed by rotenone, DPI, NAC, and CPT. NF-κB inhibitor BAY11-7082 and ERK inhibitor PD98059 inhibited TNF-α-induced LOX-1 expression. CPT and NAC suppressed TNF-α-induced LOX-1 expression and phosphorylation of NF-κB p65 and ERK in rat aorta. These data suggested that TNF-α induced LOX-1 expression via ROS activated NF-κB/ERK pathway, which could be inhibited by CPT. This study provides new insights for the anti-atherosclerotic effect of CPT.

  14. Inhibition of prostaglandin E(2) signaling through the EP(1) receptor does not affect prostacyclin production in human endothelial cells.

    PubMed

    Kaneshiro, Tatsuya; Okumura, Masae; Maalouf, Samer; Uflacker, Andre; Maruyama, Takayuki; Kawamori, Toshihiko

    2009-11-01

    Accumulating evidence suggests that cyclooxygenase-2 (COX-2) and prostaglandin E(2) (PGE(2)) may play an important role in colon carcinogenesis. Thus, blockage of this pathway may be a suitable strategy for colon cancer chemoprevention. Recent clinical studies suggest that COX-2 inhibitors cause adverse cardiovascular effects due to prostacyclin (PGI(2)) inhibition. To test our hypothesis that inhibition of PGE(2) signaling through E-prostanoid (EP) receptors may offer a safer cardiovascular profile than COX-2 inhibition, we analyzed expression of 6-keto PGF(1alpha), a hydrated form of PGI(2) and PGI(2) synthase, which was stimulated with cytokines in human umbilical vein endothelial cells (HUVECs) treated with the EP(1) receptor antagonist ONO-8711 or the COX-2 inhibitor celecoxib. ONO-8711 did not inhibit both 6-keto PGF(1alpha) production and PGIS expression, whereas celecoxib did in HUVECs. ONO-8711 also inhibited cytokine-induced tissue factor expression in HUVECs. These results suggest that ONO-8711 may be a safer chemopreventive agent with respect to cardiovascular events.

  15. Bevacizumab radiosensitizes non-small cell lung cancer xenografts by inhibiting DNA double-strand break repair in endothelial cells.

    PubMed

    Gao, Hui; Xue, Jianxin; Zhou, Lin; Lan, Jie; He, Jiazhuo; Na, Feifei; Yang, Lifei; Deng, Lei; Lu, You

    2015-08-28

    The aims of this study were to evaluate the effects of biweekly bevacizumab administration on a tumor microenvironment and to investigate the mechanisms of radiosensitization that were induced by it. Briefly, bevacizumab was administered intravenously to Balb/c nude mice bearing non-small cell lung cancer (NSCLC) H1975 xenografts; in addition, bevacizumab was added to NSCLC or endothelial cells (ECs) in vitro, followed by irradiation (IR). The anti-tumor efficacy, anti-angiogenic efficacy and repair of DNA double-strand breaks (DSBs) were evaluated. The activation of signaling pathways was determined using immunoprecipitation (IP) and WB analyses. Finally, biweekly bevacizumab administration inhibited the growth of H1975 xenografts and induced vascular normalization periodically. Bevacizumab more significantly increased cellular DSB and EC apoptosis when administered 1 h prior to 12 Gy/1f IR than when administered 5 days prior to IR, thereby inhibiting tumor angiogenesis and growth. In vitro, bevacizumab more effectively increased DSBs and apoptosis prior to IR and inhibited the clonogenic survival of ECs but not NSCLC cells. Using IP and WB analyses, we confirmed that bevacizumab can directly inhibit the phosphorylation of components of the VEGR2/PI3K/Akt/DNA-PKcs signaling pathway that are induced by IR in ECs. In conclusion, bevacizumab radiosensitizes NSCLC xenografts mainly by inhibiting DSB repair in ECs rather than by inducing vascular normalization.

  16. Rhein lysinate inhibits monocyte adhesion to human umbilical vein endothelial cells by blocking p38 signaling pathway.

    PubMed

    Lin, Yajun; Zhen, Yongzhan; Liu, Jiang; Wei, Jie; Tu, Ping; Hu, Gang

    2013-11-01

    The objective of this study was to investigate the effect of rhein lysinate (RHL) on monocyte adhesion and its mechanism. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the growth inhibition by drugs. The monocyte chemoattractant protein (MCP)-1 levels were assayed using MCP-1 ELISA. The expression of proteins was detected by Western blotting analysis. The results indicated that RHL inhibited monocyte adhesion in a dose- and time-dependent manner. RHL (<20 μmol/L) and lipopolysaccharide (LPS) had no effect on viability of human umbilical vein endothelial cells. Therefore, 20 μmol/L RHL was selected for this study. RHL inhibited secretion of MCP-1 induced by LPS and expression of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1. In the meantime, both RHL and p38 inhibitor (SB203580) inhibited phosphorylation of p38 and mitogen-activated protein kinase-activated protein kinase-2 (MAPKAPK-2) and transcription and expression of ICAM-1 and VCAM-1. In conclusion, RHL inhibits the transcription and expression of ICAM-1 and VCAM-1 by the p38/MAPKAPK-2 signaling pathway, and the effect of RHL on transcription and expression of ICAM-1 and VCAM-1 is similar to p38 inhibitor. RHL could be a prophylactic drug for atherosclerosis.

  17. Aspalathin and nothofagin from rooibos (Aspalathus linearis) inhibit endothelial protein C receptor shedding in vitro and in vivo.

    PubMed

    Kwak, Soyoung; Han, Min-Su; Bae, Jong-Sup

    2015-01-01

    Aspalathin (Asp) and nothofagin (Not) are two major active dihydrochalcones found in green rooibos, which have been reported for their anti-oxidant activity. Increasing evidence has demonstrated that beyond its role in the activation of protein C, endothelial cell protein C receptor (EPCR) is also involved in vascular inflammation. EPCR activity is markedly changed by ectodomain cleavage and its release as the soluble EPCR. EPCR can be shed from the cell surface, which is mediated by tumor necrosis factor-α converting enzyme (TACE). However, little is known about the effects of Asp and Not on EPCR shedding. Our results demonstrated that Asp and Not induced potent inhibition of phorbol-12-myristate 13-acetate (PMA)-, tumor necrosis factor (TNF)-α-, interleukin (IL)-1β, and cecal ligation and puncture (CLP)-induced EPCR shedding. Asp and Not also inhibited the expression and activity of PMA-induced TACE in endothelial cells. Asp and Not also suppressed CLP-induced protein C decrease in mice and thrombin generation in HUVECs. In addition, treatment with Asp and Not resulted in reduced PMA-stimulated phosphorylation of p38, extracellular regulated kinase (ERK) 1/2, and c-Jun N-terminal kinase (JNK). These results demonstrate the potential of Asp and Not as an anti-sEPCR shedding reagent against PMA and CLP-mediated EPCR shedding.

  18. Extract from Aronia melanocarpa fruits potentiates the inhibition of platelet aggregation in the presence of endothelial cells

    PubMed Central

    Luzak, Boguslawa; Golanski, Jacek; Rozalski, Marek; Krajewska, Urszula; Olas, Beata

    2010-01-01

    Introduction Some polyphenolic compounds extracted from Aronia melanocarpa fruits (AM) have been reported to be cardioprotective agents. In this study we evaluated the ability of AM extract to increase the efficacy of human umbilical vein endothelial cells (HUVECs) to inhibit platelet functions in vitro. Material and methods This study encompasses two models of monitoring platelet reactivity: optical aggregation and platelet degranulation (monitored as the surface CD62P expression) in PRP upon the stimulation with ADP. Results We observed that only at low concentrations (5 µg/ml) did AM extract significantly improve antiplatelet action of HUVECs towards ADP-activated platelets in the aggregation test. Conclusions It is concluded that the potentiating effect of AM extract on the endothelial cell-mediated inhibition of platelet aggregation clearly depends on the used concentrations of Aronia-derived active compounds. Therefore, despite these encouraging preliminary outcomes on the beneficial effects of AM extract polyphenols, more profound dose-effect studies should certainly be considered before the implementation of Aronia-originating compounds in antiplatelet therapy and the prevention of cardiovascular diseases. PMID:22371737

  19. Silencing stromal interaction molecule 1 by RNA interference inhibits the proliferation and migration of endothelial progenitor cells

    SciTech Connect

    Kuang, Chun-yan; Yu, Yang; Guo, Rui-wei; Qian, De-hui; Wang, Kui; Den, Meng-yang; Shi, Yan-kun; Huang, Lan

    2010-07-23

    Research highlights: {yields} STIM1 and TRPC1 are expressed in EPCs. {yields} Knockdown of STIM1 inhibits the proliferation, migration and SOCE of EPCs. {yields} TRPC1-SOC cooperates with STIM1 to mediate the SOCE of EPCs. -- Abstract: Knockdown of stromal interaction molecule 1 (STIM1) significantly suppresses neointima hyperplasia after vascular injury. Endothelial progenitor cells (EPCs) are the major source of cells that respond to endothelium repair and contribute to re-endothelialization by reducing neointima formation after vascular injury. We hypothesized that the effect of STIM1 on neointima hyperplasia inhibition is mediated through its effect on the biological properties of EPCs. In this study, we investigated the effects of STIM1 on the proliferation and migration of EPCs and examined the effect of STIM1 knockdown using cultured rat bone marrow-derived EPCs. STIM1 was expressed in EPCs, and knockdown of STIM1 by adenoviral delivery of small interfering RNA (siRNA) significantly suppressed the proliferation and migration of EPCs. Furthermore, STIM1 knockdown decreased store-operated channel entry 48 h after transfection. Replenishment with recombinant human STIM1 reversed the effects of STIM1 knockdown. Our data suggest that the store-operated transient receptor potential canonical 1 channel is involved in regulating the biological properties of EPCs through STIM1. STIM1 is a potent regulator of cell proliferation and migration in rat EPCs and may play an important role in the biological properties of EPCs.

  20. C-reactive protein inhibits insulin activation of endothelial nitric oxide synthase via the immunoreceptor tyrosine-based inhibition motif of FcgammaRIIB and SHIP-1.

    PubMed

    Tanigaki, Keiji; Mineo, Chieko; Yuhanna, Ivan S; Chambliss, Ken L; Quon, Michael J; Bonvini, Ezio; Shaul, Philip W

    2009-06-05

    Insulin promotes the cardiovascular protective functions of the endothelium including NO production by endothelial NO synthase (eNOS), which it stimulates via Akt kinase which phosphorylates eNOS Ser1179. C-reactive protein (CRP) is an acute-phase reactant that is positively correlated with cardiovascular disease risk in patients with type 2 diabetes. We previously showed that CRP inhibits eNOS activation by insulin by blunting Ser1179 phosphorylation. We now elucidate the underlying molecular mechanisms. We first show in mice that CRP inhibits insulin-induced eNOS phosphorylation, indicating that these processes are operative in vivo. In endothelial cells we find that CRP attenuates insulin-induced Akt phosphorylation, and CRP antagonism of eNOS is negated by expression of constitutively active Akt; the inhibitory effect of CRP on Akt is also observed in vivo. A requirement for the IgG receptor FcgammaRIIB was demonstrated in vitro using blocking antibody, and reconstitution experiments with wild-type and mutant FcgammaRIIB in NIH3T3IR cells revealed that these processes require the ITIM (immunoreceptor tyrosine-based inhibition motif) of the receptor. Furthermore, we find that endothelium express SHIP-1 (Src homology 2 domain-containing inositol 5'-phosphatase 1), that CRP induces SHIP-1 stimulatory phosphorylation in endothelium in culture and in vivo, and that SHIP-1 knockdown by small interfering RNA prevents CRP antagonism of insulin-induced eNOS activation. Thus, CRP inhibits eNOS stimulation by insulin via FcgammaRIIB and its ITIM, SHIP-1 activation, and resulting blunted activation of Akt. These findings provide mechanistic linkage among CRP, impaired insulin signaling in endothelium, and greater cardiovascular disease risk in type 2 diabetes.

  1. GX1-mediated anionic liposomes carrying adenoviral vectors for enhanced inhibition of gastric cancer vascular endothelial cells.

    PubMed

    Xiong, Dan; Liu, Zhongbing; Bian, Tierong; Li, Juan; Huang, Wenjun; Jing, Pei; Liu, Li; Wang, Yunlong; Zhong, Zhirong

    2015-12-30

    Gastric cancer is a highly lethal malignancy and its 5-year survival rate remains depressed in spite of multiple treatment options. Targeting drug delivery to tumor vasculature may be a promising strategy for gastric cancer therapy, for it can block the nutrition source of tumor and inhibit the metastasis and invasion in a certain extent. In present study, we have prepared the drug-targeting delivery system of peptide GX1-mediated anionic liposomes carrying adenoviral vectors (GX1-Ad5-AL), in which the tumor suppressor gene of PTEN was integrated into DNA of Ad5 and the GX1 peptide could play targeting role to vascular of gastric cancer. The inhibition ability of GX1-Ad5-AL to human gastric cancer cell lines (SGC-7901) and human umbilical vein endothelial cells (HUVEC) was evaluated by MTT assay. Further, the cell migration assay was carried out in transwell inserts and the cells uptaking of GX1-Ad5-AL was detected by confocal laser scanning microscopy. The experimental results indicated that the average cell proliferation inhibition rates resulted from the drug delivery system of GX1-Ad5-AL in SGC-7901 and HUVEC were 68.36% and 64.13%, respectively which were higher than that resulted from GX1 or Ad5-AL. Meanwhile, results of cell migration experiment demonstrated that GX1-Ad5-AL could significantly suppress the migration of gastric cancer cell of SGC-7901. Moreover, both the imaging from confocal laser scanning microscopy and the quantitative analysis of fluorescence intensity showed that, GX1-Ad5-AL was more easily uptaken by SGC-7901 cells, as compared to Ad5-AL. Therefore, the formulation of GX1-Ad5-AL was effective for enhancing the inhibition effect and suppressing the migration of gastric cancer vascular endothelial cells.

  2. Synergistic effects of methylnaltrexone with 5-fluorouracil and bevacizumab on inhibition of vascular endothelial growth factor-induced angiogenesis.

    PubMed

    Singleton, Patrick A; Garcia, Joe G N; Moss, Jonathan

    2008-06-01

    Many patients with cancer receive combinations of drug treatments that include 5-fluorouracil (5-FU) and bevacizumab. Therapeutic doses of 5-FU are often associated with unwanted side effects, and bevacizumab is costly. Therefore, we explored potential agents that can reduce the therapeutic concentration of these drugs. Our data indicate that methylnaltrexone (MNTX), a peripheral antagonist of the mu-opioid receptor, exerts a synergistic effect with 5-FU and bevacizumab on inhibition of vascular endothelial growth factor (VEGF)-induced human pulmonary microvascular endothelial cell (EC) proliferation and migration, two key components in cancer-associated angiogenesis. MNTX inhibited EC proliferation with an IC(50) of approximately 100 nmol/L. Adding 100 nmol/L MNTX to EC shifted the IC(50) of 5-FU from approximately 5 micromol/L to approximately 7 nmol/L. Further, adding 50 ng/mL MNTX shifted the IC(50) of bevacizumab on inhibition of EC migration from approximately 25 to approximately 6 ng/mL. These synergistic effects were not observed with naltrexone, a tertiary mu-opioid receptor antagonist. On a mechanistic level, we observed that treatment of human EC with MNTX, but not naltrexone, increased receptor protein tyrosine phosphatase mu activity, which was independent of mu-opioid receptor expression. Silencing receptor protein tyrosine phosphatase mu expression (small interfering RNA) in human EC inhibited both synergy between MNTX and bevacizumab or 5-FU and increased VEGF-induced tyrosine phosphorylation of Src and p190 RhoGAP with enhanced activation of Akt and the actin cytoskeletal regulatory protein, RhoA, whereas silencing Src, Akt, or RhoA blocked VEGF-induced angiogenic events. Therefore, addition of MNTX could potentially lower the therapeutic doses of 5-FU and bevacizumab, which could improve index.

  3. Induction of transient macroapertures in endothelial cells through RhoA inhibition by Staphylococcus aureus factors.

    PubMed

    Boyer, Laurent; Doye, Anne; Rolando, Monica; Flatau, Gilles; Munro, Patrick; Gounon, Pierre; Clément, René; Pulcini, Céline; Popoff, Michel R; Mettouchi, Amel; Landraud, Luce; Dussurget, Olivier; Lemichez, Emmanuel

    2006-06-05

    The GTPase RhoA is a major regulator of the assembly of actin stress fibers and the contractility of the actomyosin cytoskeleton. The epidermal cell differentiation inhibitor (EDIN) and EDIN-like ADP-ribosyltransferases of Staphylococcus aureus catalyze the inactivation of RhoA, producing actin cable disruption. We report that purified recombinant EDIN and EDIN-producing S. aureus provoke large transcellular tunnels in endothelial cells that we have named macroapertures (MAs). These structures open transiently, followed by the appearance of actin-containing membrane waves extending over the aperture. Disruption of actin cables, either directly or indirectly, through rhoA RNAi knockdown also triggers the formation of MAs. Intoxication of endothelial monolayers by EDIN produces a loss of barrier function and provides direct access of the endothelium basement membrane to S. aureus.

  4. Induction of transient macroapertures in endothelial cells through RhoA inhibition by Staphylococcus aureus factors

    PubMed Central

    Boyer, Laurent; Doye, Anne; Rolando, Monica; Flatau, Gilles; Munro, Patrick; Gounon, Pierre; Clément, René; Pulcini, Céline; Popoff, Michel R.; Mettouchi, Amel; Landraud, Luce; Dussurget, Olivier; Lemichez, Emmanuel

    2006-01-01

    The GTPase RhoA is a major regulator of the assembly of actin stress fibers and the contractility of the actomyosin cytoskeleton. The epidermal cell differentiation inhibitor (EDIN) and EDIN-like ADP-ribosyltransferases of Staphylococcus aureus catalyze the inactivation of RhoA, producing actin cable disruption. We report that purified recombinant EDIN and EDIN-producing S. aureus provoke large transcellular tunnels in endothelial cells that we have named macroapertures (MAs). These structures open transiently, followed by the appearance of actin-containing membrane waves extending over the aperture. Disruption of actin cables, either directly or indirectly, through rhoA RNAi knockdown also triggers the formation of MAs. Intoxication of endothelial monolayers by EDIN produces a loss of barrier function and provides direct access of the endothelium basement membrane to S. aureus. PMID:16754962

  5. LL37 inhibits the inflammatory endothelial response induced by viral or endogenous DNA.

    PubMed

    Merkle, Monika; Pircher, Joachim; Mannell, Hanna; Krötz, Florian; Blüm, Philipp; Czermak, Thomas; Gaitzsch, Erik; Schneider, Christine; Köppel, Simone; Ribeiro, Andrea; Wörnle, Markus

    2015-12-01

    In viral infection, morbidity and mortality often result from extrahepatic disease manifestations such as vasculitis. We hereby show that human microvascular endothelial cells express viral receptors of the innate immune system which are induced upon ligand engagement. Furthermore, stimulation of endothelial cells with the synthetic analog of viral DNA, poly (dA:dT), human DNA and hepatitis B virus-containing immunoprecipitates from a patient with polyarteritis nodosa induces an inflammatory response including the upregulation of adhesion molecules, which is mediated exclusively by TLR9 and involves an IRF3-dependent pathway. Thus, endothelial cells are able to actively participate in immune mediated vascular inflammation caused by viral infections. Furthermore, we provide evidence for the ability of LL37 to bind and internalize viral or endogenous DNA into non-immune cells. DNA nucleotides internalized by LL37 suppress the production of proinflammatory mediators suggesting a protective effect against direct responses to viral infection or circulating DNA-fragments of endogenous origin. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Hop derived flavonoid xanthohumol inhibits endothelial cell functions via AMPK activation

    PubMed Central

    Gallo, Cristina; Dallaglio, Katiuscia; Bassani, Barbara; Rossi, Teresa; Rossello, Armando; Noonan, Douglas M.; D'Uva, Gabriele; Bruno, Antonino; Albini, Adriana

    2016-01-01

    Angiogenesis, a process characterized by the formation of new blood vessels from pre-existing ones, is a crucial step in tumor growth and dissemination. Recently, increased attention has been addressed to the ability of flavonoids to prevent cancer by suppressing angiogenesis, strategy that we named “angioprevention”. Several natural compounds exert their anti-tumor properties by activating 5′ adenosine monophosphate-activated protein kinase (AMPK), a key regulator of metabolism in cancer cells. Drugs with angiopreventive activities, in particular metformin, regulate AMPK in endothelial cells. Here we investigated the involvement of AMPK in the anti-angiogenic effects of xanthohumol (XN), the major prenylated flavonoid of the hop plant, and mechanisms of action. The anti-angiogenic activity of XN was more potent than epigallocatechin-3-gallate (EGCG). Treatment of endothelial cells with XN led to increased AMPK phosphorylation and activity. Functional studies using biochemical approaches confirmed that AMPK mediates XN anti-angiogenic activity. AMPK activation by XN was mediated by CAMMKβ, but not LKB1. Analysis of the downstream mechanisms showed that XN-induced AMPK activation reduced nitric oxide (NO) levels in endothelial cells by decreasing eNOS phosphorylation. Finally, AKT pathway was inactivated by XN as part of its anti-angiogenic activity, but independently from AMPK, suggesting that these two signaling pathways proceed autonomously. Our study dissects the molecular mechanism by which XN exerts its potent anti-angiogenic activity, pointing out AMPK as a crucial signal transducer. PMID:27494895

  7. Maslinic Acid Inhibits Proliferation of Renal Cell Carcinoma Cell Lines and Suppresses Angiogenesis of Endothelial Cells

    PubMed Central

    Thakor, Parth; Song, Wenzhe; Subramanian, Ramalingam B.; Thakkar, Vasudev R.; Vesey, David A.

    2017-01-01

    Despite the introduction of many novel therapeutics in clinical practice, metastatic renal cell carcinoma (RCC) remains a treatment-resistant cancer. As red and processed meat are considered risk factors for RCC, and a vegetable-rich diet is thought to reduce this risk, research into plant-based therapeutics may provide valuable complementary or alternative therapeutics for the management of RCC. Herein, we present the antiproliferative and antiangiogenic effects of maslinic acid, which occurs naturally in edible plants, particularly in olive fruits, and also in a variety of medicinal plants. Human RCC cell lines (ACHN, Caki-1, and SN12K1), endothelial cells (human umbilical vein endothelial cell line [HUVEC]), and primary cultures of kidney proximal tubular epithelial cells (PTEC) were treated with maslinic acid. Maslinic acid was relatively less toxic to PTEC when compared with RCC under similar experimental conditions. In RCC cell lines, maslinic acid induced a significant reduction in proliferation, proliferating cell nuclear antigen, and colony formation. In HUVEC, maslinic acid induced a significant reduction in capillary tube formation in vitro and vascular endothelial growth factor. This study provides a rationale for incorporating a maslinic acid–rich diet either to reduce the risk of developing kidney cancer or as an adjunct to existing antiangiogenic therapy to improve efficacy. PMID:28405545

  8. Inhibitive effects of anti-oxidative vitamins on mannitol-induced apoptosis of vascular endothelial cells.

    PubMed

    Pan, Kai-yu; Shen, Mei-ping; Ye, Zhi-hong; Dai, Xiao-na; Shang, Shi-qiang

    2006-10-01

    Study blood vessel injury and gene expression indicating vascular endothelial cell apoptosis induced by mannitol with and without administration of anti-oxidative vitamins. Healthy rabbits were randomly divided into four groups. Mannitol was injected into the vein of the rabbit ear in each animal. Pre-treatment prior to mannitol injection was performed with normal saline (group B), vitamin C (group C) and vitamin E (group D). Blood vessel injury was assessed under electron and light microscopy. In a second experiment, cell culture specimen of human umbilical vein endothelial cells were treated with mannitol. Pre-treatment was done with normal saline (sample B), vitamin C (sample C) and vitamin E (sample D). Total RNA was extracted with the original single step procedure, followed by hybridisation and analysis of gene expression. In the animal experiment, serious blood vessel injury was seen in group A and group B. Group D showed light injury only, and normal tissue without pathological changes was seen in group C. Of all 330 apoptosis-related genes analysed in human cell culture specimen, no significant difference was seen after pre-treatment with normal saline, compared with the gene chip without pre-treatment. On the gene chip pre-treated with vitamin C, 45 apoptosis genes were down-regulated and 34 anti-apoptosis genes were up-regulated. Pre-treatment with vitamin E resulted in the down-regulation of 3 apoptosis genes. Vitamin C can protect vascular endothelial cells from mannitol-induced injury.

  9. Hop derived flavonoid xanthohumol inhibits endothelial cell functions via AMPK activation.

    PubMed

    Gallo, Cristina; Dallaglio, Katiuscia; Bassani, Barbara; Rossi, Teresa; Rossello, Armando; Noonan, Douglas M; D'Uva, Gabriele; Bruno, Antonino; Albini, Adriana

    2016-09-13

    Angiogenesis, a process characterized by the formation of new blood vessels from pre-existing ones, is a crucial step in tumor growth and dissemination. Recently, increased attention has been addressed to the ability of flavonoids to prevent cancer by suppressing angiogenesis, strategy that we named "angioprevention". Several natural compounds exert their anti-tumor properties by activating 5' adenosine monophosphate-activated protein kinase (AMPK), a key regulator of metabolism in cancer cells. Drugs with angiopreventive activities, in particular metformin, regulate AMPK in endothelial cells. Here we investigated the involvement of AMPK in the anti-angiogenic effects of xanthohumol (XN), the major prenylated flavonoid of the hop plant, and mechanisms of action. The anti-angiogenic activity of XN was more potent than epigallocatechin-3-gallate (EGCG). Treatment of endothelial cells with XN led to increased AMPK phosphorylation and activity. Functional studies using biochemical approaches confirmed that AMPK mediates XN anti-angiogenic activity. AMPK activation by XN was mediated by CAMMKβ, but not LKB1. Analysis of the downstream mechanisms showed that XN-induced AMPK activation reduced nitric oxide (NO) levels in endothelial cells by decreasing eNOS phosphorylation. Finally, AKT pathway was inactivated by XN as part of its anti-angiogenic activity, but independently from AMPK, suggesting that these two signaling pathways proceed autonomously. Our study dissects the molecular mechanism by which XN exerts its potent anti-angiogenic activity, pointing out AMPK as a crucial signal transducer.

  10. Inhibition of cortisol production with metyrapone prevents mental stress-induced endothelial dysfunction and baroreflex impairment.

    PubMed

    Broadley, Andrew J M; Korszun, Ania; Abdelaal, Eltigani; Moskvina, Valentina; Jones, Christopher J H; Nash, Gerard B; Ray, Clare; Deanfield, John; Frenneaux, Michael P

    2005-07-19

    This study was designed to investigate the role of cortisol in stress-induced endothelial dysfunction and impaired baroreflex sensitivity (BRS) by blocking cortisol production with metyrapone before subjecting healthy volunteers to mental stress. Mental stress raises cortisol levels and is associated with increased coronary heart disease (CHD) morbidity and mortality, especially from sudden cardiac death. It also causes endothelial dysfunction and impaired BRS. We measured brachial artery flow-mediated dilation (FMD), a measure of endothelial function, and BRS in 36 subjects without CHD risk factors who were then randomized in a double-blind fashion to oral metyrapone 750 mg x 2 or placebo. Five hours later we subjected subjects to mental stress and then remeasured endothelial function and BRS. Prestress cortisol levels were significantly higher in the placebo group at 270.5 (30.9) nmol/l versus 89.1 (11.8) nmol/l (p = 0.01), and the increase with stress was higher at 57.9 (17.9) nmol/l versus 11.2 (2.2) nmol/l (p < 0.001). In the placebo group, compared to baseline, FMD and BRS fell significantly from 4.5% (0.7%) to 1.4% (1.1%) (p = 0.02) and 21.4 (2.3) ms/mmHg to 16.3 (1.5) ms/mmHg (p = 0.04), respectively. In the metyrapone group, FMD and BRS were unchanged from baseline: 4.3% (0.9%) versus 5.1% (0.8%) (p = 0.48) and 26.4 (2.9) ms/mmHg versus 24.9 (2.6) ms/mmHg (p = 0.62), respectively. Analysis of covariation showed a significant effect of metyrapone on change in both FMD (p = 0.009) and BRS (p = 0.024). Stress-related endothelial dysfunction and BRS impairment can be prevented by blocking cortisol production with metyrapone, demonstrating a direct or facilitative role for cortisol in these phenomena and suggesting mechanisms by which stress contributes to CHD and sudden cardiac death.

  11. Advanced glycation end-products inhibition improves endothelial dysfunction in rheumatoid arthritis.

    PubMed

    Syngle, Ashit; Vohra, Kanchan; Garg, Nidhi; Kaur, Ladbans; Chand, Prem

    2012-02-01

    Chronic inflammation in rheumatoid arthritis is associated with vascular endothelial dysfunction. The objective was to study the efficacy and safety of advanced glycation end products (AGEs) inhibitor (benfotiamine 50 mg + pyridoxamine 50 mg + methylcobalamin 500 μg, Vonder(®) (ACME Lifescience, Baddi, Himachal Pradesh, India)) on endothelial function in rheumatoid arthritis (RA). Twenty-four patients with established active RA with high disease activity (Disease Activity Score of 28 joints [DAS28 score] > 5.1) despite treatment with stable doses of conventional disease-modifying antirheumatic drugs were investigated. Inflammatory disease activity (DAS28 and Health Assessment Questionnaire-Disability Index [HAQ-DI] scores, erythrocyte sedimentation rate [ESR] and C-reactive protein [CRP]), markers of endothelial dysfunction, serum nitrite concentration and endothelium-dependent and -independent vasodilation of the brachial artery were measured before and after 12 weeks therapy with twice a day oral AGEs inhibitor. After treatment, flow-mediated vasodilation improved from 9.64 ± 0.65% to 15.82 ± 1.02% (P < 0.01), whereas there was no significant change in endothelium-independent vasodilation with nitroglycerin and baseline diameter; serum nitrite concentration significantly reduced from 5.6 ± 0.13 to 5.1 ± 0.14 μmol/L (P = 0.004), ESR from 63.00 ± 3.5 to 28.08 ± 1.5 mm in the first h (P < 0.01) and CRP levels from 16.7 ± 4.1 to 10.74 ± 2.9 mg/dL (P < 0.01). DAS28 and HAQ-DI scores were significantly reduced, from 5.9 ± 0.17 to 3.9 ± 0.17 (P < 0.01) and 4.6 ± 0.17 to 1.7 ± 0.22 (P < 0.01), respectively. Advanced glycation end products inhibitor improves endothelial dysfunction and inflammatory disease activity in RA. In RA, endothelial dysfunction is part of the disease process and is mediated by AGEs-induced inflammation. © 2011 The Authors. International Journal of Rheumatic Diseases © 2011 Asia Pacific League of Associations for Rheumatology and

  12. Targeted inhibition of {alpha}v{beta}3 integrin with an RNA aptamer impairs endothelial cell growth and survival

    SciTech Connect

    Mi Jing; Zhang Xiuwu; Giangrande, Paloma H.; McNamara, James O.; Nimjee, Shahid M.; Sarraf-Yazdi, Shiva; Sullenger, Bruce A.; Clary, Bryan M. . E-mail: mi001@duke.edu

    2005-12-16

    {alpha}v{beta}3 integrin is a crucial factor involved in a variety of physiological processes, such as cell growth and migration, tumor invasion and metastasis, angiogenesis, and wound healing. {alpha}v{beta}3 integrin exerts its effect by regulating endothelial cell (EC) migration, proliferation, and survival. Inhibiting the function of {alpha}v{beta}3 integrin, therefore, represents a potential anti-cancer, anti-thrombotic, and anti-inflammatory strategy. In this study, we tested an RNA aptamer, Apt-{alpha}v{beta}3 that binds recombinant {alpha}v{beta}3 integrin, for its ability to bind endogenous {alpha}v{beta}3 integrin on the surface of cells in culture and to subsequently affect cellular response. Our data illustrate that Apt-{alpha}v{beta}3 binds {alpha}v{beta}3 integrin expressed on the surface of live HUVECs. This interaction significantly decreases both basal and PDGF-induced cell proliferation as well as inhibition of cell adhesion. Apt-{alpha}v{beta}3 can also reduce PDGF-stimulated tube formation and increase HUVEC apoptosis through inhibition of FAK phosphorylation pathway. Our results demonstrate that by binding to its target, Apt-{alpha}v{beta}3 can efficiently inhibit human EC proliferation and survival, resulting in reduced angiogenesis. It predicts that Apt-{alpha}v{beta}3 could become useful in both tumor imaging and the treatment of tumor growth, atherosclerosis, thrombosis, and inflammation.

  13. Vascular endothelial growth factor is neuroprotective against ischemic brain injury by inhibiting scavenger receptor A expression on microglia.

    PubMed

    Xu, Zheng; Han, Kaiwei; Chen, Jigang; Wang, Chunhui; Dong, Yan; Yu, Mingkun; Bai, Rulin; Huang, Chenguang; Hou, Lijun

    2017-09-01

    Vascular endothelial growth factor (VEGF) is a secreted mitogen associated with angiogenesis. VEGF has long been thought to be a potent neurotrophic factor for the survival of spinal cord neurons. However, the role of VEGF in the regulation of ischemic brain injury remains unclear. In this study, rats were subjected to MCAO (middle cerebral artery occlusion) followed by intraperitoneal injection of VEGF165 (10 mg/kg) immediately after surgery and once daily until the day 10. The expression of target genes was assayed using qPCR, western blot and immunofluorescence to investigate the role of VEGF165 in regulating ischemic brain injury. We found that VEGF165 significantly inhibited MCAO-induced up-regulation of Scavenger receptor class A (SR-A) on microglia in a VEGFR1-dependent manner. VEGF165 inhibited lipopolysaccharide (LPS)-induced expression of proinflammatory cytokines IL-1β, tumor necrosis factor alpha (TNF-α) and iNOS in microglia. More importantly, the role of VEGF165 in inhibiting neuroinflammation is partially abolished by SR-A over-expression. SR-A further reduced the protective effect of VEGF165 in ischemic brain injury. These data suggest that VEGF165 suppresses neuroinflammation and ischemic brain injury by inhibiting SR-A expression, thus offering a new target for prevention of ischemic brain injury. © 2017 International Society for Neurochemistry.

  14. Inhibition of human endothelial cell proliferation by ShIF, a vacuolar H(+)-ATPase-like protein.

    PubMed

    Tulin, Edgardo E; Onoda, Nobuhisa; Hasegawa, Masakazu; Nomura, Hitoshi; Kitamura, Toshio

    2002-01-24

    ShIF is a bone marrow stroma cell-derived factor originally identified to support proliferation of bone marrow cells in vitro. This protein shares high sequence homology to the yeast vacuolar H(+)-ATPase subunit, Vph1p, and the 116 kDa proton pump of the rat and bovine synaptic vesicle, Vpp1. We examined the function of ShIF in the proliferation of human umbilical vein endothelial cells (HUVEC). ShIF inhibited HUVEC proliferation in a dose-dependent manner. Recombinant ShIF added at 10 and 20 ng/ml inhibited HUVEC proliferation by 21.6 and 44.3%, respectively and increasing the concentration of ShIF to 100 ng/ml inhibited proliferation by as much as 55.5%. When HUVEC cells were cultured at various concentrations of ShIF in the presence of anti-ShIF antibody, the inhibitory effects of ShIF to HUVEC proliferation were abrogated by 89-91% indicating that the activity of ShIF to HUVEC was specific. HUVEC cultured in the presence of ShIF and bafilomycin, a specific inhibitor of ATPase, resulted to a 90% growth inhibition. Thus, ShIF may act as an antagonist to the ATPase complex by disrupting the production of cellular ATP thereby decreasing the ability of HUVEC to proliferate.

  15. Linagliptin-mediated DPP-4 inhibition ameliorates kidney fibrosis in streptozotocin-induced diabetic mice by inhibiting endothelial-to-mesenchymal transition in a therapeutic regimen.

    PubMed

    Kanasaki, Keizo; Shi, Sen; Kanasaki, Megumi; He, Jianhua; Nagai, Takako; Nakamura, Yuka; Ishigaki, Yasuhito; Kitada, Munehiro; Srivastava, Swayam Prakash; Koya, Daisuke

    2014-06-01

    Kidney fibrosis is the final common pathway of all progressive chronic kidney diseases, of which diabetic nephropathy is the leading cause. Endothelial-to-mesenchymal transition (EndMT) has emerged as one of the most important origins of matrix-producing fibroblasts. Dipeptidyl peptidase-4 (DPP-4) inhibitors have been introduced into the market as antidiabetes drugs. Here, we found that the DPP-4 inhibitor linagliptin ameliorated kidney fibrosis in diabetic mice without altering the blood glucose levels associated with the inhibition of EndMT and the restoration of microRNA 29s. Streptozotocin-induced diabetic CD-1 mice exhibited kidney fibrosis and strong immunoreactivity for DPP-4 by 24 weeks after the onset of diabetes. At 20 weeks after the onset of diabetes, mice were treated with linagliptin for 4 weeks. Linagliptin-treated diabetic mice exhibited a suppression of DPP-4 activity/protein expression and an amelioration of kidney fibrosis associated with the inhibition of EndMT. The therapeutic effects of linagliptin on diabetic kidneys were associated with the suppression of profibrotic programs, as assessed by mRNA microarray analysis. We found that the induction of DPP-4 observed in diabetic kidneys may be associated with suppressed levels of microRNA 29s in diabetic mice; linagliptin restored microRNA 29s and suppressed DPP-4 protein levels. Using cultured endothelial cells, we found that linagliptin inhibited TGF-β2-induced EndMT, and such anti-EndMT effects of linagliptin were mediated through microRNA 29 induction. These results indicate the possible novel pleiotropic action of linagliptin to restore normal kidney function in diabetic patients with renal impairment.

  16. Far-infrared radiation inhibits proliferation, migration, and angiogenesis of human umbilical vein endothelial cells by suppressing secretory clusterin levels.

    PubMed

    Hwang, Soojin; Lee, Dong-Hoon; Lee, In-Kyu; Park, Young Mi; Jo, Inho

    2014-04-28

    Far-infrared (FIR) radiation is known to lessen the risk of angiogenesis-related diseases including cancer. Because deficiency of secretory clusterin (sCLU) has been reported to inhibit angiogenesis of endothelial cells (EC), we investigated using human umbilical vein EC (HUVEC) whether sCLU mediates the inhibitory effects of FIR radiation. Although FIR radiation ranging 3-25μm wavelength at room temperature for 60min did not alter EC viability, further incubation in the culture incubator (at 37°C under 5% CO2) after radiation significantly inhibited EC proliferation, in vitro migration, and tube formation in a time-dependent manner. Under these conditions, we found decreased sCLU mRNA and protein expression in HUVEC and decreased sCLU protein secreted in culture medium. Expectedly, the replacement of control culture medium with the FIR-irradiated conditioned medium significantly decreased wound closure and tube formation of HUVEC, and vice versa. Furthermore, neutralization of sCLU with anti-sCLU antibody also mimicked all observed inhibitory effects of FIR radiation. Moreover, treatment with recombinant human sCLU protein completely reversed the inhibitory effects of FIR radiation on EC migration and angiogenesis. Lastly, vascular endothelial growth factor also increased sCLU secretion in the culture medium, and wound closure and tube formation of HUVEC, which were significantly reduced by FIR radiation. Our results demonstrate a novel mechanism by which FIR radiation inhibits the proliferation, migration, and angiogenesis of HUVEC, via decreasing sCLU.

  17. Trichosanatine alleviates oxidized low-density lipoprotein induced endothelial cells injury via inhibiting the LOX-1/p38 MAPK pathway.

    PubMed

    Zhang, Lei; Jia, Yu-Hua; Zhao, Xiao-Shan; Zhou, Feng-Hua; Pan, Yun-Yun; Wan, Qiang; Cui, Xiao-Bing; Sun, Xue-Gang; Chen, Yu-Yao; Zhang, Yu; Cheng, Sai-Bo

    2016-01-01

    The LOX-1/p38 mitogen-activated protein kinase (MAPK) pathway has been proved to participate in the endothelial dysfunction in atherosclerosis. Trichosanatineis is an active compound isolated from the peel of Trichosanthes kirilowii. This study aims to determine whether trichosanatine prevents the oxidized low-density lipoprotein (ox-LDL)-induced insult through inhibition of the LOX-1/p38 MAPK pathway in HUVECs. HUVECs were treated with 150 mg/ml ox-LDL for 24 h to establish an ox-LDL-induced endothelial injury model. Cell viability, mitochondrial membrane potential (MMP), apoptosis, reactive oxygen species (ROS) level, LOX-1 and p38 MAPK expression level were measured. The results indicated that HUVECs were pretreated with either 100 mM trichosanatine or LOX-1 shRNA prior to exposure to ox-LDL for 24 h. Exposure of HUVECs to 150 mg/ml ox-LDL for 24 h significantly up-regulated the expression levels of LOX-1. The increased expression levels of LOX-1 were markedly attenuated by pretreatment with 100 mM trichosanatine. In addition, the ox-LDL-induced increase in phosphorylated (p) p38 MAPK expression was ameliorated by pretreatment with LOX-1 shRNA. Pretreatment of HUVECs with either trichosanatine or LOX-1 shRNA before exposure to ox-LDL significantly inhibited the ox-LDL-induced injuries, as evidenced by an increase in cell viability, a decrease in apoptotic cells, a ROS generation and a loss of MMP. In conclusion, we have demonstrated for the first time that the LOX-1/p38 MAPK pathway contributes to the ox-LDL-induced injury in HUVECs. Meanwhile, the trichosanatine protects the HUVECs against ox-LDL-induced injury at least in part by inhibiting the activated of LOX-1/p38 MAPK pathway.

  18. Trichosanatine alleviates oxidized low-density lipoprotein induced endothelial cells injury via inhibiting the LOX-1/p38 MAPK pathway

    PubMed Central

    Zhang, Lei; Jia, Yu-Hua; Zhao, Xiao-Shan; Zhou, Feng-Hua; Pan, Yun-Yun; Wan, Qiang; Cui, Xiao-Bing; Sun, Xue-Gang; Chen, Yu-Yao; Zhang, Yu; Cheng, Sai-Bo

    2016-01-01

    The LOX-1/p38 mitogen-activated protein kinase (MAPK) pathway has been proved to participate in the endothelial dysfunction in atherosclerosis. Trichosanatineis is an active compound isolated from the peel of Trichosanthes kirilowii. This study aims to determine whether trichosanatine prevents the oxidized low-density lipoprotein (ox-LDL)-induced insult through inhibition of the LOX-1/p38 MAPK pathway in HUVECs. HUVECs were treated with 150 mg/ml ox-LDL for 24 h to establish an ox-LDL-induced endothelial injury model. Cell viability, mitochondrial membrane potential (MMP), apoptosis, reactive oxygen species (ROS) level, LOX-1 and p38 MAPK expression level were measured. The results indicated that HUVECs were pretreated with either 100 mM trichosanatine or LOX-1 shRNA prior to exposure to ox-LDL for 24 h. Exposure of HUVECs to 150 mg/ml ox-LDL for 24 h significantly up-regulated the expression levels of LOX-1. The increased expression levels of LOX-1 were markedly attenuated by pretreatment with 100 mM trichosanatine. In addition, the ox-LDL-induced increase in phosphorylated (p) p38 MAPK expression was ameliorated by pretreatment with LOX-1 shRNA. Pretreatment of HUVECs with either trichosanatine or LOX-1 shRNA before exposure to ox-LDL significantly inhibited the ox-LDL-induced injuries, as evidenced by an increase in cell viability, a decrease in apoptotic cells, a ROS generation and a loss of MMP. In conclusion, we have demonstrated for the first time that the LOX-1/p38 MAPK pathway contributes to the ox-LDL-induced injury in HUVECs. Meanwhile, the trichosanatine protects the HUVECs against ox-LDL-induced injury at least in part by inhibiting the activated of LOX-1/p38 MAPK pathway. PMID:28078016

  19. Foeniculum vulgare Mill. increases cytosolic Ca(2+) concentration and inhibits store-operated Ca(2+) entry in vascular endothelial cells.

    PubMed

    Han, A Young; Lee, Hui Su; Seol, Geun Hee

    2016-12-01

    This study assessed the effects of essential oil of Foeniculum vulgare Mill. (fennel oil) and of trans-anethole, the main component of fennel oil, on extracellular Ca(2+)-induced store-operated Ca(2+) entry (SOCE) into vascular endothelial (EA) cells and their mechanisms of action. Components of fennel oil were analyzed by gas chromatography-mass spectrometry. Cytosolic Ca(2+) concentration ([Ca(2+)]c) in EA cells was determined using Fura-2 fluorescence. In the presence of extracellular Ca(2+), fennel oil significantly increased [Ca(2+)]c in EA cells; this increase was significantly inhibited by the Ca(2+) channel blockers La(3+) and nifedipine. In contrast, fennel oil induced [Ca(2+)]c was significantly lower in Ca(2+)-free solution, suggesting that fennel oil increases [Ca(2+)]c mainly by enhancing Ca(2+) influx into EA cells. [Ca(2+)]c mobilization by trans-anethole was similar to that of fennel oil. Moreover, SOCE was suppressed by fennel oil and trans-anethole. SOCE was also attenuated by lanthanum (La(3+)), a non-selective cation channel (NSC) blocker; 2-aminoethoxydiphenyl borane (2-APB), an inositol 1,4,5-triphosphate (IP3) receptor inhibitor and SOCE blocker; and U73122, an inhibitor of phospholipase C (PLC). Further, SOCE was more strongly inhibited by La(3+) plus fennel oil or trans-anethole than by La(3+) alone. These findings suggest that fennel oil and trans-anethole significantly inhibit SOCE-induced [Ca(2+)]c increase in vascular endothelial cells and that these reactions may be mediated by NSC, IP3-dependent Ca(2+) mobilization, and PLC activation.

  20. Sirt 1 activator inhibits the AGE-induced apoptosis and p53 acetylation in human vascular endothelial cells.

    PubMed

    Li, Peng; Zhang, Lina; Zhou, Changyong; Lin, Nan; Liu, Aiguo

    2015-01-01

    Advanced glycation end products (AGEs) by nonenzymatic glycation reactions are extremely accumulated in the diabetic vascular cells, neurons, and glia, and are confirmed to play important role in the pathogenesis of diabetes mellitus -induced cardiovascular complications. Sirt 1, known as mammalian sirtuin, has been recognized to regulate insulin secretion and protect cells against oxidative stress, which is promoted by the accumulated AGEs in cardiovascular cells. In the present study, we treated human endothelial Eahy926 cells with AGEs, and determined the apoptosis induction, caspase activation, the Sirt 1 activity, the expression and acetylation of p53. Then we manipulated Sirt 1 activity with a Sirt 1 activator, Resveratrol (RSV), and a Sirt 1 inhibitor, sirtinol, in the AGE-BSA-treated Eahy926 cells, and then re-evaluated the apoptosis induction, caspase activation, the expression and acetylation of p53. Results demonstrated that AGEs induced apoptosis in the human endothelial Eahy926 cells, by promoting the cytochrome c release, activation of caspase 9/3. Also, the AGE-BSA treatment promoted the total p53 level and acetylated (Ac) p53, but reduced the Sirt 1 level and activity. On the other hand, the Sirt 1 inhibitor/activator not only deteriorated/ameliorated the promotion to p53 level and Ac p53, but also aggravated/inhibited the AGE-induced apoptosis and the promotion to apoptosis-associated signaling molecules. In conclusion, the present study confirmed the apoptosis promotion by AGEs in endothelial Eahy926 cells, by regulating the Sirt 1 activity and p53 signaling, it also implies the protective role of Sirt 1 activator against the AGE-induced apoptosis.

  1. Secreted APE1/Ref-1 inhibits TNF-α-stimulated endothelial inflammation via thiol-disulfide exchange in TNF receptor.

    PubMed

    Park, Myoung Soo; Choi, Sunga; Lee, Yu Ran; Joo, Hee Kyoung; Kang, Gun; Kim, Cuk-Seong; Kim, Soo Jin; Lee, Sang Do; Jeon, Byeong Hwa

    2016-03-11

    Apurinic apyrimidinic endonuclease 1/Redox factor-1 (APE1/Ref-1) is a multifunctional protein with redox activity and is proved to be secreted from stimulated cells. The aim of this study was to evaluate the functions of extracellular APE1/Ref-1 with respect to leading anti-inflammatory signaling in TNF-α-stimulated endothelial cells in response to acetylation. Treatment of TNF-α-stimulated endothelial cells with an inhibitor of deacetylase that causes intracellular acetylation, considerably suppressed vascular cell adhesion molecule-1 (VCAM-1). During TSA-mediated acetylation in culture, a time-dependent increase in secreted APE1/Ref-1 was confirmed. The acetyl moiety of acetylated-APE1/Ref-1 was rapidly removed based on the removal kinetics. Additionally, recombinant human (rh) APE1/Ref-1 with reducing activity induced a conformational change in rh TNF-α receptor 1 (TNFR1) by thiol-disulfide exchange. Following treatment with the neutralizing anti-APE1/Ref-1 antibody, inflammatory signals via the binding of TNF-α to TNFR1 were remarkably recovered, leading to up-regulation of reactive oxygen species generation and VCAM-1, in accordance with the activation of p66(shc) and p38 MAPK. These results strongly indicate that anti-inflammatory effects in TNF-α-stimulated endothelial cells by acetylation are tightly linked to secreted APE1/Ref-1, which inhibits TNF-α binding to TNFR1 by reductive conformational change, with suggestion as an endogenous inhibitor of vascular inflammation.

  2. Influence of GSH synthesis inhibition on temporal distribution of NAD+/NADH during vascular endothelial cells proliferation.

    PubMed

    Busu, C; Atanasiu, V; Caldito, G; Aw, T Y

    2014-01-01

    Pathological conditions states such as stroke, diabetes mellitus, hypertension, dyslipidemia are associated with increased levels of free radicals that alter normal function of the vascular endothelium and perturb vascular homeostasis. The redox couples reduced glutathione (GSH)/oxidized glutathione (GSSG), NADH/NAD+, and NADPH/NADP+ play major functions in the intracellular redox balance. Any decrease in tissue or systemic GSH levels under the aforementioned pathologies would enhance oxidative damage to the vascular endothelium. Beside their role as coenzyme that participate in cellular metabolism, pyridine nucleotides serve also as substrate for enzymes involved in DNA repair and longevity. There is scant data on NAD+/NADH kinetics and distribution during human cells proliferation. Here, we determined the influence of cellular GSH status on the early dynamics of nuclear-to-cytosol (N-to-C) NAD+ and nuclear NADH kinetics (6 h interval) over 72 h of endothelial cell proliferation. The IHEC cell line was used as a surrogate for human brain micro vascular endothelial cells. Inhibition of GSH synthesis by buthionine sulfoximine (BSO) and sustained low cellular GSH significantly increased nuclear NADH levels (p<0.01), which correlated with lower nuclear GSH and prolonged cell cycle S-phase. When BSO was removed the pattern of nuclear NAD+ resembled that of control group, but nuclear NADH concentrations remained elevated, as in GSH deficient cells (p<0.01). The coincidence of high nuclear NADH and lower nuclear NAD+ with S-phase prolongation are suggestive of CtBP and NAD+-dependent DNA repair enzyme activation under conditions of decreased cellular GSH. These results provide important insights into GSH control of vascular endothelial growth and restitution, key processes in the restoration of the endothelium adjacent to the post-injury lesion site.

  3. ClC-3 deficiency prevents apoptosis induced by angiotensin II in endothelial progenitor cells via inhibition of NADPH oxidase.

    PubMed

    Liu, Jing; Zhang, Fei-Fei; Li, Lei; Yang, Jing; Liu, Jie; Guan, Yong-Yuan; Du, Yan-Hua

    2013-10-01

    Endothelial progenitor cells (EPCs) play an important role in postnatal neovascularization and re-endothelialization in response to tissue ischemia and endothelial injury. It is reported that the circulating EPCs number is decreased during hypertension. However, the detailed mechanism is still unclear. Our previous studies have shown that ClC-3 chloride channel is up-regulated with the development of hypertension. This study aims to test whether ClC-3 participates in EPC apoptosis under the condition of increased oxidative stress in angiotensin II (Ang II)-induced hypertension. The results showed that stimulation with 10(-6)mol/L Ang II significantly up-regulated the endogenous ClC-3 expression and increased intracellular reactive oxygen species (ROS) generation in EPCs of wild type mice, accompanied by an enhanced NADPH oxidase activity and the expression of gp91(phox) (NOX-2), a key catalytic subunit of NADPH oxidase. However, these effects of Ang II were significantly reduced in EPCs of ClC-3(-/-) mice. Compared with control, treatment with Ang II induced EPCs apoptosis in wild type mice, concomitantly with declined Bcl-2/Bax ratio, depressed mitochondrial membrane potential and activation of poly(ADP-ribose) polymerase, which was remarkably prevented by both ClC-3 knockout and NADPH oxidase inhibitor apocynin. In addition, the role of ClC-3 deficiency in protecting EPCs against Ang II-induced oxidative stress and apoptosis was further confirmed in Ang II-infused hypertensive mice in vivo. In conclusion, ClC-3 deficiency inhibited Ang II-induced EPC apoptosis via suppressing ROS generation derived from NADPH oxidase.

  4. Ethyl-p-methoxycinnamate isolated from kaempferia galanga inhibits inflammation by suppressing interleukin-1, tumor necrosis factor-α, and angiogenesis by blocking endothelial functions

    PubMed Central

    Umar, Muhammad Ihtisham; Asmawi, Mohd Zaini; Sadikun, Amirin; Majid, Amin Malik Shah Abdul; Al-Suede, Fouad Saleih R.; Hassan, Loiy Elsir Ahmed; Altaf, Rabia; Ahamed, Mohamed B. Khadeer

    2014-01-01

    OBJECTIVE: The present study aimed to investigate the mechanisms underlying the anti-inflammatory and anti-angiogenic effects of ethyl-p-methoxycinnamate isolated from Kaempferia galanga. METHODS: The anti-inflammatory effects of ethyl-p-methoxycinnamate were assessed using the cotton pellet granuloma assay in rats, whereby the levels of interleukin-1 and tumor necrosis factor-α were measured in the animals' blood. In addition, the levels of interleukin, tumor necrosis factor, and nitric oxide were measured in vitro using the human macrophage cell line (U937). The analgesic effects of ethyl-p-methoxycinnamate were assessed by the tail flick assay in rats. The anti-angiogenic effects were evaluated first by the rat aortic ring assay and, subsequently, by assessing the inhibitory effects of ethyl-p-methoxycinnamate on vascular endothelial growth factor, proliferation, migration, and tube formation in human umbilical vein endothelial cells. RESULTS: Ethyl-p-methoxycinnamate strongly inhibited granuloma tissue formation in rats. It prolonged the tail flick time in rats by more than two-fold compared with the control animals. The inhibition of interleukin and tumor necrosis factor by ethyl-p-methoxycinnamate was significant in both in vivo and in vitro models; however, only a moderate inhibition of nitric oxide was observed in macrophages. Furthermore, ethyl-p-methoxycinnamate considerably inhibited microvessel sprouting from the rat aorta. These mechanistic studies showed that ethyl-p-methoxycinnamate strongly inhibited the differentiation and migration of endothelial cells, which was further confirmed by the reduced level of vascular endothelial growth factor. CONCLUSION: Ethyl-p-methoxycinnamate exhibits significant anti-inflammatory potential by inhibiting pro-inflammatory cytokines and angiogenesis, thus inhibiting the main functions of endothelial cells. Thus, ethyl-p-methoxycinnamate could be a promising therapeutic agent for the treatment of inflammatory and

  5. Inhibitive effects of anti-oxidative vitamins on mannitol-induced apoptosis of vascular endothelial cells

    PubMed Central

    Pan, Kai-yu; Shen, Mei-ping; Ye, Zhi-hong; Dai, Xiao-na; Shang, Shi-qiang

    2006-01-01

    Objective: Study blood vessel injury and gene expression indicating vascular endothelial cell apoptosis induced by mannitol with and without administration of anti-oxidative vitamins. Methods: Healthy rabbits were randomly divided into four groups. Mannitol was injected into the vein of the rabbit ear in each animal. Pre-treatment prior to mannitol injection was performed with normal saline (group B), vitamin C (group C) and vitamin E (group D). Blood vessel injury was assessed under electron and light microscopy. In a second experiment, cell culture specimen of human umbilical vein endothelial cells were treated with mannitol. Pre-treatment was done with normal saline (sample B), vitamin C (sample C) and vitamin E (sample D). Total RNA was extracted with the original single step procedure, followed by hybridisation and analysis of gene expression. Results: In the animal experiment, serious blood vessel injury was seen in group A and group B. Group D showed light injury only, and normal tissue without pathological changes was seen in group C. Of all 330 apoptosis-related genes analysed in human cell culture specimen, no significant difference was seen after pre-treatment with normal saline, compared with the gene chip without pre-treatment. On the gene chip pre-treated with vitamin C, 45 apoptosis genes were down-regulated and 34 anti-apoptosis genes were up-regulated. Pre-treatment with vitamin E resulted in the down-regulation of 3 apoptosis genes. Conclusion: Vitamin C can protect vascular endothelial cells from mannitol-induced injury. PMID:16972325

  6. Advanced glycation inhibition and protection against endothelial dysfunction induced by coumarins and procyanidins from Mammea neurophylla.

    PubMed

    Dang, Bach Tai; Gény, Charlotte; Blanchard, Patricia; Rouger, Caroline; Tonnerre, Pierre; Charreau, Béatrice; Rakolomalala, Gilbertine; Randriamboavonjy, Joseph Iharinjaka; Loirand, Gervaise; Pacaud, Pierre; Litaudon, Marc; Richomme, Pascal; Séraphin, Denis; Derbré, Séverine

    2014-07-01

    Advanced glycation end-products (AGEs) are associated with many pathogenic disorders such as pathogenesis of diabetes or endothelial dysfunction leading to cardiovascular events. Therefore, the identification of new anti-AGE molecules or extracts aims at preventing such pathologies. Many Clusiaceae and Calophyllaceae species are used in traditional medicines to treat arterial hypertension as well as diabetes. Focusing on these plant families, an anti-AGE plant screening allowed us to select Mammea neurophylla for further phytochemical and biological studies. Indeed, both DCM and MeOH stem bark extracts demonstrated in vitro their ability to prevent inflammation in endothelial cells and to reduce vasoconstriction. A bioguided fractionation of these extracts allowed us to point out 4-phenyl- and 4-(1-acetoxypropyl)coumarins and procyanidins as potent inhibitors of AGE formation, potentially preventing endothelial dysfunction. The fractionation steps also led to the isolation of two new compounds, namely neurophyllols A and B from the DCM bark extract together with thirteen known mammea A and E coumarins (mammea A/AA, mammea A/AB, mammea A/BA, mammea A/BB, mammea A/AA cycloD, mammea A/AB cycloD, disparinol B, mammea A/AB cycloE, ochrocarpin A, mammea A/AA cycloF, mammea A/AB cycloF, mammea E/BA, mammea E/BB) as well as δ-tocotrienol, xanthones (1-hydroxy-7-methoxyxanthone, 2-hydroxyxanthone) and triterpenes (friedelin and betulinic acid). During this study, R,S-asperphenamate, previously described from fungal origin was also purified.

  7. Effect of interleukin-6 inhibition on coronary microvascular and endothelial function in myocardial infarction.

    PubMed

    Holte, Espen; Kleveland, Ola; Ueland, Thor; Kunszt, Gabor; Bratlie, Marte; Broch, Kaspar; Michelsen, Annika E; Bendz, Bjørn; Amundsen, Brage H; Aakhus, Svend; Damås, Jan Kristian; Gullestad, Lars; Aukrust, Pål; Wiseth, Rune

    2017-04-21

    Interleukin-6 (IL-6) is a driver of inflammation and associated endothelial cell activation in acute coronary syndromes. We evaluated the effect of the IL-6 receptor antagonist tocilizumab on coronary microvascular function and endothelial dysfunction measured by coronary flow reserve (CFR) and markers of endothelial cell activation in patients with non-ST-elevation myocardial infarction (NSTEMI). This substudy was part of a two-centre, double-blind, randomised, placebo-controlled trial evaluating the effect of a single dose of tocilizumab in NSTEMI. Markers of endothelial cell activation (vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule-1 and von Willebrand factor) were assessed in 117 patients. In 42 of these patients, 20 assigned to placebo and 22 to tocilizumab, we measured CFR. Blood samples were obtained at seven consecutive time points between day 1 and 3. CFR was measured by transthoracic echocardiography during hospitalisation and after 6 months. Tocilizumab did not affect CFR during hospitalisation (tocilizumab: 3.4±0.8 vs placebo: 3.3±1.2, p=0.80). CFR improved significantly in both groups at 6 months. Patients in the tocilizumab group had significantly higher area under the curve for VCAM-1 (median 622 vs 609 ng/mL/hour, tocilizumab and placebo respectively, p=0.003). There were inverse correlations between VCAM-1 and CFR in the placebo (hospitalisation: r=-0.74, p<0.01, 6 months: r=-0.59, p<0.01), but not in the tocilizumab group (hospitalisation: r=0.20, p=0.37, 6 months r=-0.28, p=0.20). Tocilizumab did not affect CFR during hospitalisation or after 6 months. Tocilizumab increased VCAM-1 levels during hospitalisation, but this was not associated with reduced CFR in these patients. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  8. Hsp90 inhibition suppresses NF-κB transcriptional activation via Sirt-2 in human lung microvascular endothelial cells.

    PubMed

    Thangjam, Gagan S; Birmpas, Charalampos; Barabutis, Nektarios; Gregory, Betsy W; Clemens, Mary Ann; Newton, Joseph R; Fulton, David; Catravas, John D

    2016-05-15

    The ability of anti-heat shock protein 90 (Hsp90) drugs to attenuate NF-κB-mediated transcription is the major basis for their anti-inflammatory properties. While the molecular mechanisms underlying this effect are not clear, they appear to be distinct in human endothelial cells. We now show for the first time that type 2 sirtuin (Sirt-2) histone deacetylase binds human NF-κB target gene promoter and prevents the recruitment of NF-κB proteins and subsequent assembly of RNA polymerase II complex in human lung microvascular endothelial cells. Hsp90 inhibitors stabilize the Sirt-2/promoter interaction and impose a "transcriptional block," which is reversed by either inhibition or downregulation of Sirt-2 protein expression. Furthermore, this process is independent of NF-κB (p65) Lysine 310 deacetylation, suggesting that it is distinct from known Sirt-2-dependent mechanisms. We demonstrate that Sirt-2 is recruited to NF-κB target gene promoter via interaction with core histones. Upon inflammatory challenge, chromatin remodeling and core histone H3 displacement from the promoter region removes Sirt-2 and allows NF-κB/coactivator recruitment essential for RNA Pol II-dependent mRNA induction. This novel mechanism may have important implications in pulmonary inflammation.

  9. HDL inhibits the effects of oxidized phospholipids on endothelial cell gene expression via multiple mechanisms[S

    PubMed Central

    Emert, Benjamin; Hasin-Brumshtein, Yehudit; Springstead, James R.; Vakili, Ladan; Berliner, Judith A.; Lusis, Aldons J.

    2014-01-01

    Oxidized 1-palmitoyl-2-arachidonyl-sn-glycero-3-phospholcholine (OxPAPC) and its component phospholipids accumulate in atherosclerotic lesions and regulate the expression of >1,000 genes, many proatherogenic, in human aortic endothelial cells (HAECs). In contrast, there is evidence in the literature that HDL protects the vasculature from inflammatory insult. We have previously shown that in HAECs, HDL attenuates the expression of several proatherogenic genes regulated by OxPAPC and 1-palmitoyl-2-(5,6-epoxyisoprostane E2)-sn-glycero-3-phosphocholine. We now demonstrate that HDL reverses >50% of the OxPAPC transcriptional response. Genes reversed by HDL are enriched for inflammatory and vascular development pathways, while genes not affected by HDL are enriched for oxidative stress response pathways. The protective effect of HDL is partially mimicked by cholesterol repletion and treatment with apoA1 but does not require signaling through scavenger receptor class B type I. Furthermore, our data demonstrate that HDL protection requires direct interaction with OxPAPC. HDL-associated platelet-activating factor acetylhydrolase (PAF-AH) hydrolyzes short-chain bioactive phospholipids in OxPAPC; however, inhibiting PAF-AH activity does not prevent HDL protection. Our results are consistent with HDL sequestering specific bioactive lipids in OxPAPC, thereby preventing their regulation of select target genes. Overall, this work implicates HDL as a major regulator of OxPAPC action in endothelial cells via multiple mechanisms. PMID:24859737

  10. Curcumin supplementation could improve diabetes-induced endothelial dysfunction associated with decreased vascular superoxide production and PKC inhibition

    PubMed Central

    2010-01-01

    Background Curcumin, an Asian spice and food-coloring agent, is known for its anti-oxidant properties. We propose that curcumin can improve diabetes-induced endothelial dysfunction through superoxide reduction. Methods Diabetes (DM) was induced in rats by streptozotocin (STZ). Daily curcumin oral feeding was started six weeks after the STZ injection. Twelve weeks after STZ injection, mesenteric arteriolar responses were recorded in real time using intravital fluorescence videomicroscopy. Superoxide and vascular protein kinase C (PKC-βII) were examined by hydroethidine and immunofluorescence, respectively. Results The dilatory response to acetylcholine (ACh) significantly decreased in DM arterioles as compared to control arterioles. There was no difference among groups when sodium nitroprusside (SNP) was used. ACh responses were significantly improved by both low and high doses (30 and 300 mg/kg, respectively) of curcumin supplementation. An oxygen radical-sensitive fluorescent probe, hydroethidine, was used to detect intracellular superoxide anion (O2●-) production. O2●- production was markedly increased in DM arterioles, but it was significantly reduced by supplementation of either low or high doses of curcumin. In addition, with a high dose of curcumin, diabetes-induced vascular PKC-βII expression was diminished. Conclusion Therefore, it is suggested that curcumin supplementation could improve diabetes-induced endothelial dysfunction significantly in relation to its potential to decrease superoxide production and PKC inhibition. PMID:20946622

  11. MicroRNA-16 inhibits feto-maternal angiogenesis and causes recurrent spontaneous abortion by targeting vascular endothelial growth factor

    PubMed Central

    Zhu, Yongsheng; Lu, Hong; Huo, Zhenghao; Ma, Zhanbin; Dang, Jie; Dang, Wei; Pan, Lin; Chen, Jing; Zhong, Huijun

    2016-01-01

    Recurrent spontaneous abortion (RSA) is a common health problem that affects women of reproductive age. Recent studies have indicated that microRNAs are important factors in miscarriage. This study investigated the role of miR-16 in regulating vascular endothelial growth factor (VEGF) expression and the pathogenesis of RSA. In this report, clinical samples revealed that miR-16 expression was significantly elevated in the villi and decidua of RSA patients. In vitro, miR-16 upregulation inhibited human umbilical vein endothelial cell proliferation, migration and tube formation. Conversely, the downregulation of miR-16 reversed these effects. In vivo, we demonstrated that abnormal miR-16 levels affect the weights of the placenta and embryo and the number of progeny and microvascular density, as well as cause recurrent abortions by controlling VEGF expression in pregnant mice. VEGF, a potential target gene of miR-16, was inversely correlated with miR-16 expression in the decidua of clinical samples. Furthermore, the luciferase reporter system demonstrated that miR-16 was found to directly downregulate the expression of VEGF by binding a specific sequence of its 3′-untranslated region (3′UTR). Collectively, these data strongly suggest that miR-16 regulates placental angiogenesis and development by targeting VEGF expression and is involved in the pathogenesis of RSA. PMID:27748453

  12. MicroRNA-16 inhibits feto-maternal angiogenesis and causes recurrent spontaneous abortion by targeting vascular endothelial growth factor.

    PubMed

    Zhu, Yongsheng; Lu, Hong; Huo, Zhenghao; Ma, Zhanbin; Dang, Jie; Dang, Wei; Pan, Lin; Chen, Jing; Zhong, Huijun

    2016-10-17

    Recurrent spontaneous abortion (RSA) is a common health problem that affects women of reproductive age. Recent studies have indicated that microRNAs are important factors in miscarriage. This study investigated the role of miR-16 in regulating vascular endothelial growth factor (VEGF) expression and the pathogenesis of RSA. In this report, clinical samples revealed that miR-16 expression was significantly elevated in the villi and decidua of RSA patients. In vitro, miR-16 upregulation inhibited human umbilical vein endothelial cell proliferation, migration and tube formation. Conversely, the downregulation of miR-16 reversed these effects. In vivo, we demonstrated that abnormal miR-16 levels affect the weights of the placenta and embryo and the number of progeny and microvascular density, as well as cause recurrent abortions by controlling VEGF expression in pregnant mice. VEGF, a potential target gene of miR-16, was inversely correlated with miR-16 expression in the decidua of clinical samples. Furthermore, the luciferase reporter system demonstrated that miR-16 was found to directly downregulate the expression of VEGF by binding a specific sequence of its 3'-untranslated region (3'UTR). Collectively, these data strongly suggest that miR-16 regulates placental angiogenesis and development by targeting VEGF expression and is involved in the pathogenesis of RSA.

  13. Chronic Embolic Pulmonary Hypertension Caused by Pulmonary Embolism and Vascular Endothelial Growth Factor Inhibition.

    PubMed

    Neto-Neves, Evandro M; Brown, Mary B; Zaretskaia, Maria V; Rezania, Samin; Goodwill, Adam G; McCarthy, Brian P; Persohn, Scott A; Territo, Paul R; Kline, Jeffrey A

    2017-04-01

    Our understanding of the pathophysiological basis of chronic thromboembolic pulmonary hypertension (CTEPH) will be accelerated by an animal model that replicates the phenotype of human CTEPH. Sprague-Dawley rats were administered a combination of a single dose each of plastic microspheres and vascular endothelial growth factor receptor antagonist in polystyrene microspheres (PE) + tyrosine kinase inhibitor SU5416 (SU) group. Shams received volume-matched saline; PE and SU groups received only microspheres or SU5416, respectively. PE + SU rats exhibited sustained pulmonary hypertension (62 ± 13 and 53 ± 14 mmHg at 3 and 6 weeks, respectively) with reduction of the ventriculoarterial coupling in vivo coincident with a large decrement in peak rate of oxygen consumption during aerobic exercise, respectively. PE + SU produced right ventricular hypokinesis, dilation, and hypertrophy observed on echocardiography, and 40% reduction in right ventricular contractile function in isolated perfused hearts. High-resolution computed tomographic pulmonary angiography and Ki-67 immunohistochemistry revealed abundant lung neovascularization and cellular proliferation in PE that was distinctly absent in the PE + SU group. We present a novel rodent model to reproduce much of the known phenotype of CTEPH, including the pivotal pathophysiological role of impaired vascular endothelial growth factor-dependent vascular remodeling. This model may reveal a better pathophysiological understanding of how PE transitions to CTEPH in human treatments.

  14. Fucoidan inhibits lymphangiogenesis by downregulating the expression of VEGFR3 and PROX1 in human lymphatic endothelial cells

    PubMed Central

    Yang, Yazong; Gao, Zixiang; Ma, Yanhong; Teng, Hongming; Liu, Zundong; Wei, Hengyun; Lu, Yanbing; Cheng, Xiaofang; Hou, Lin; Zou, Xiangyang

    2016-01-01

    Lymphangiogenesis is one of the promoters of tumor lymphatic metastasis. Fucoidan which is a fucose-enriched sulfated polysaccharide has effect on various pharmacological activities including anti-metastasis activity. However, the inhibitory effect of fucoidan on lymphangiogenesis remains unclear. Here, fucoidan extracted from U. pinnatifida sporophylls suppressed HLECs proliferation, migration and tube-like structure formation, and had inhibitory effect of tumor-induced lymphangiogenesis in vitro. Additionally, we found that fucoidan had a dose-dependent depressive effect on the expressions of PROX1, vascular endothelial growth factor receptor 3 (VEGFR3), NF-κB, phospho-PI3K and phospho-Akt in HLECs. Moreover, anti-lymphangiogenesis effect of fucoidan was assessed by using mouse tumor model. In summary, fucoidan inhibit tumor lymphangiogenesis and lymphatic metastasis by suppressing the NF-κB/PI3K/Akt signaling pathway through reduced levels of PROX1 and VEGFR3. PMID:27203545

  15. Fucoidan inhibits lymphangiogenesis by downregulating the expression of VEGFR3 and PROX1 in human lymphatic endothelial cells.

    PubMed

    Yang, Yazong; Gao, Zixiang; Ma, Yanhong; Teng, Hongming; Liu, Zundong; Wei, Hengyun; Lu, Yanbing; Cheng, Xiaofang; Hou, Lin; Zou, Xiangyang

    2016-06-21

    Lymphangiogenesis is one of the promoters of tumor lymphatic metastasis. Fucoidan which is a fucose-enriched sulfated polysaccharide has effect on various pharmacological activities including anti-metastasis activity. However, the inhibitory effect of fucoidan on lymphangiogenesis remains unclear. Here, fucoidan extracted from U. pinnatifida sporophylls suppressed HLECs proliferation, migration and tube-like structure formation, and had inhibitory effect of tumor-induced lymphangiogenesis in vitro. Additionally, we found that fucoidan had a dose-dependent depressive effect on the expressions of PROX1, vascular endothelial growth factor receptor 3 (VEGFR3), NF-κB, phospho-PI3K and phospho-Akt in HLECs. Moreover, anti-lymphangiogenesis effect of fucoidan was assessed by using mouse tumor model. In summary, fucoidan inhibit tumor lymphangiogenesis and lymphatic metastasis by suppressing the NF-κB/PI3K/Akt signaling pathway through reduced levels of PROX1 and VEGFR3.

  16. 5'-nitro-indirubinoxime inhibits inflammatory response in TNF-alpha stimulated human umbilical vein endothelial cells.

    PubMed

    Kim, Eun-Jung; Park, Won-Hwan; Ahn, Sang-Gun; Yoon, Jung-Hoon; Kim, Si-Wouk; Kim, Soo-A

    2010-07-01

    Inflammation plays a critical role in the development of atherosclerosis and TNF-alpha, a major inflammatory cytokine, induces inflammatory responses by enhancing the expression of adhesion molecules and the secretion of inflammatory mediators. Indirubin is an active compound of Polygonum tinctorium Lour (P. tinctorium) that has the ability to suppress inflammation. Previously, we described the novel indirubin derivative, 5'-nitro-indirubinoxime (5'-NIO), and demonstrated that it has potent anti-proliferative activity against various human cancer cells. In this study, we examined the effect of 5'-NIO on the TNF-alpha induced inflammatory conditions of human umbilical vein endothelial cells (HUVECs). We found that 5'-NIO inhibited TNF-alpha induced MCP-1 and IL-8 expression at the RNA and protein levels in HUVECs. Specifically, 5'-NIO significantly inhibited the TNF-alpha stimulated release of MCP-1 and IL-8, with levels that were only 19.8% and 30.9% of those of untreated control cells, respectively. Furthermore, 5'-NIO largely inhibited the adhesion of U937 cells to HUVECs by decreasing the expression level of ICAM-1 and VCAM-1. Overall, these observations suggest that 5'-NIO has the potential for use as an anti-atherosclerotic agent.

  17. Extracellular nucleotide inhibits cell proliferation and negatively regulates Toll-like receptor 4 signalling in human progenitor endothelial cells.

    PubMed

    Xiao, Zhilin; Yang, Mei; Fang, Li; Lv, Qingshan; He, Qing; Deng, Minjie; Liu, Xueting; Chen, Xiaobin; Chen, Meifang; Xie, Xiumei; Hu, Jinyue

    2012-07-01

    Extracellular nucleotides mediate a wide range of physiological effects by interacting with plasma membrane P2 purinergic receptors. P2 receptors are expressed in certain kinds of stem cells, and function to induce cytokine expression and to modulate cell proliferation. We have analysed the expression and the function of P2 receptors in human umbilical cord blood-derived EPCs (endothelial progenitor cells). EPCs expressed P2X4,6,7 and P2Y2,4,11,13,14 receptors and extracellular ATP inhibited EPCs proliferation. As in a previous study, EPCs expressed functional TLR4 (Toll-like receptor 4) and activation of TLR4 by LPS (lipopolysaccharide) evoked a pro-inflammatory immune response. When human EPCs were stimulated with LPS and nucleotides, ATP or UTP inhibited the expression of pro-inflammatory cytokines including MCP-1 (monocyte chemoattractant protein-1), IFNα (interferon α), TNFα (tumour necrosis factor α) and adhesion molecule VCAM-1 (vascular cell adhesion molecule 1) induced by LPS. ATP and UTP also down-regulated the gene expression of TLR4, CD14 and MyD88 (myeloid differentiation factor 88), a TLR adaptor molecule, and protein expression of CD14 and MyD88. Moreover, the phosphorylation of NF-κB (nuclear factor κB) p65 induced by TLR4 activation was inhibited partly by ATP or UTP at concentrations of 1-5 μM. These results suggest that extracellular nucleotides negatively regulate EPCs proliferation and TLR4 signalling.

  18. A standardized bamboo leaf extract inhibits monocyte adhesion to endothelial cells by modulating vascular cell adhesion protein-1

    PubMed Central

    Choi, Sunga; Park, Myoung Soo; Lee, Yu Ran; Lee, Young Chul; Kim, Tae Woo; Do, Seon-Gil; Kim, Dong Seon

    2013-01-01

    Bamboo leaves (Phyllostachys pubescens Mazel ex J. Houz (Poacea)) have a long history of food and medical applications in Asia, including Japan and Korea. They have been used as a traditional medicine for centuries. We investigated the mechanism of anti-inflammatory activity of a bamboo leaf extract (BLE) on tumor necrosis factor-alpha (TNF-α)-induced monocyte adhesion in human umbilical vein endothelial cells (HUVECs). Exposure of HUVECs to BLE did not inhibit cell viability or cause morphological changes at concentrations ranging from 1 µg/ml to 1 mg/ml. Treatment with 0.1 mg/ml BLE caused 63% inhibition of monocyte adhesion in TNF-α-activated HUVECs, which was associated with 38.4% suppression of vascular cell adhesion molecule-1 expression. Furthermore, TNF-α-induced reactive oxygen species generation was decreased to 47.9% in BLE treated TNF-α-activated HUVECs. BLE (0.05 mg/ml) also caused about 50% inhibition of interleukin-6 secretion from lipopolysaccharide-stimulated monocyte. The results indicate that BLE may be clinically useful as an anti-inflammatory or anti-oxidant for human cardiovascular disease including atherosclerosis. PMID:23422838

  19. Heme oxygenase-1 inhibits the expression of adhesion molecules associated with endothelial cell activation via inhibition of NF-kappaB RelA phosphorylation at serine 276.

    PubMed

    Seldon, Mark P; Silva, Gabriela; Pejanovic, Nadja; Larsen, Rasmus; Gregoire, Isabel Pombo; Filipe, Josina; Anrather, Josef; Soares, Miguel P

    2007-12-01

    Heme oxygenase-1 (HO-1; encoded by the Hmox1 gene) catalyzes the degradation of free heme into biliverdin, via a reaction that releases iron (Fe) and carbon monoxide. We report that HO-1 down-regulates the proinflammatory phenotype associated with endothelial cell (EC) activation by reducing intracellular nonprotein-bound Fe (labile Fe). EC isolated from Hmox1(-/-) mice have higher levels of intracellular labile Fe and reactive oxygen species (ROS) as compared with EC isolated from Hmox1(+/+) mice. Basal and TNF-induced expression of VCAM-1, ICAM-1, and E-selectin were increased in Hmox1(-/-) vs Hmox1(+/+) EC, an effect reversed by Fe chelation using deferoxamine mesylate (DFO). Fe chelation inhibits TNF-driven transcription of Vcam-1, Icam-1, and E-selectin, as assessed using luciferase reporter assays. This effect is associated with inhibition of the transcription factor NF-kappaB via a mechanism that is not associated with the inhibition of IkappaBalpha phosphorylation/degradation or NF-kappaB (i.e., RelA) nuclear translocation, although it affects very modestly NF-kappaB binding to DNA kappaB consensus sequences in the Vcam-1 and E-selectin promoters. HO-1 inhibits NF-kappaB (i.e., RelA) phosphorylation at Ser(276), a phosphoacceptor that is critical to sustain TNF-driven NF-kappaB activity in EC. This effect was mimicked by Fe chelation as well as by antioxidants (N-acetylcysteine). In conclusion, we demonstrate a novel mechanism via which HO-1 down-modulates the proinflammatory phenotype of activated EC, i.e., the inhibition of RelA phosphorylation at Ser(276).

  20. The ATF site mediates downregulation of the cyclin A gene during contact inhibition in vascular endothelial cells.

    PubMed Central

    Yoshizumi, M; Hsieh, C M; Zhou, F; Tsai, J C; Patterson, C; Perrella, M A; Lee, M E

    1995-01-01

    Contact inhibition mediates monolayer formation and withdrawal from the cell cycle in vascular endothelial cells. In studying the cyclins--key regulators of the cell cycle--in bovine aortic endothelial cells (BAEC), we found that levels of cyclin A mRNA decreased in confluent BAEC despite the presence of 10% fetal calf serum. We then transfected into BAEC a series of plasmids containing various lengths of the human cyclin A 5' flanking sequence and the luciferase gene. Plasmids containing 3,200, 516, 406, 266, or 133 bp of the human cyclin A promoter directed high luciferase activity in growing but not confluent BAEC. In contrast, a plasmid containing 23 bp of the cyclin A promoter was associated with a 65-fold reduction in activity in growing BAEC, and the promoter activities of this plasmid were identical in both growing and confluent BAEC. Mutation of the activating transcription factor (ATF) consensus sequence at bp -80 to -73 of the cyclin A promoter decreased its activity, indicating the critical role of the ATF site. We identified by gel mobility shift analysis protein complexes that bound to the ATF site in nuclear extracts from growing but not confluent BAEC and identified (with antibodies) ATF-1 as a binding protein in nuclear extracts from growing cells. Also, ATF-1 mRNA levels decreased in confluent BAEC. Taken together, these data suggest that the ATF site and its cognate binding proteins play an important role in the downregulation of cyclin A gene expression during contact inhibition. PMID:7760822

  1. Blocking IL-22, a potential treatment strategy for adenomyosis by inhibiting crosstalk between vascular endothelial and endometrial stromal cells

    PubMed Central

    Shang, Wen-Qing; Yu, Jia-Jun; Zhu, Lei; Zhou, Wen-Jie; Chang, Kai-Kai; Wang, Qing; Li, Ming-Qing

    2015-01-01

    Our previous work has demonstrated that interleukin-22 (IL-22) enhances the invasiveness of endometrial stromal cells (ESCs) of adenomyosis in an autocrine manner. In the present study, we further investigated whether IL-22 mediated crosstalk between vascular endothelial cells (VECs) and ESCs in vitro. Here we found that VECs in ectopic lesion from women with adenomyosis highly expressed IL-22 receptors IL-22R1 and IL-10R2. Both recombinant human IL-22 (rhIL-22) and IL-22 from ESCs increased IL-22R1 and IL-10R2 expression on human umbilical vein endothelial cells (HUVECs). Treatment with rhIL-22 led to an elevation of HUVECs viability, but did not influence HUVECs apoptosis. In contrast, anti-human IL-22 neutralizing antibody (α-IL-22) inhibited HUVECs viability induced by supernatants of ESCs. Stimulation with rhIL-22 or ESCs up-regulated CD105 expression on HUVECs and promoted angiogenesis, and α-IL-22 could reverse these effect induced by ESC. Compared to non-treated HUVECs, HUVECs educated by rh-IL-22 or ESCs could further up-regulate Ki-67 and proliferating cell nuclear antigen (PCNA) expression, and down-regulate Fas ligand (FasL) expression in ESCs. However, these effects induced by ESC-educated HUVECs were inhibited by α-IL-22. These results suggest that IL-22 derived from ESC promotes IL-22 receptors expression and enhances the viability, activation and angiogenesis of HUVEC. In turn, the educated HUVEC may further stimulate proliferation and restricts apoptosis of ESC. The integral effect may contribute to the progress of adenomyosis. Blocking IL-22 can disturb crosstalk between ESC and VEC mediated by IL-22, suggesting that blocking IL-22 may be a potential treatment strategy for adenomyosis. PMID:26692924

  2. Cimetidine inhibits the adhesion of gastric cancer cells expressing high levels of sialyl Lewis x in human vascular endothelial cells by blocking E-selectin expression.

    PubMed

    Liu, Fu-Rong; Jiang, Cheng-Gang; Li, Yan-Shu; Li, Jia-Bin; Li, Feng

    2011-04-01

    Cimetidine has been shown to have anti-metastatic activity and improves the survival of patients with colorectal cancer. One hypothesis is its modulation of the expression of the cell adhesion molecule by target organ endothelial cells. Because of the inconclusive results in clinical trials of gastric cancer, we investigated the effects of cimetidine on the adhesion of gastric cancer cells to activated endothelial cells and on the expression of some cell adhesion molecules. Human endothelial cells were pre-incubated with cimetidine for 6 h, incubated with the cytokine tumor necrosis factor for 4 h, and the endothelial surface expression of E-selectin was evaluated by flow cytometry, immunostaining and ELISA. Further, we investigated E-selectin mRNA expression by RT-PCR. Three gastric cancer cell lines (SGC-7901, MGC-803, BGC-823) and a normal gastric epithelial cell line, GES-1, were studied for the surface expression of sialyl Lewis x by flow cytometry and immunostaining. Adherence of CFSE-labeled gastric cancer cells and GES-1 cells to endothelial cell monolayers was determined. Cimetidine significantly reduced E-selectin expression of activated endothelial cells, but did not influence E-selectin expression at the mRNA level. Three gastric cancer cell lines expressed high levels of sialyl Lewis x, whereas GES-1 did not. Cimetidine also significantly decreased gastric cancer cell adherence to stimulated endothelial cells. The inhibition of E-selectin expression corresponded to the reduction of tumor cell adherence. The effects of cimetidine on tumor adhesion were almost nullified by pre-incubation with E-selectin and sialyl Lewis x antibody. Furthermore, there was no significant change of GES-1 adherence to endothelial cells by TNF-α, cimetidine, E-selectin and sialyl Lewis x antibody. The inhibiton of gastric cancer cell adherence to cytokine-stimulated endothelial cells treated with cimetidine appears to result from blocking endothelial E-selectin expression

  3. Arginase-2 is cooperatively up-regulated by nitric oxide and histone deacetylase inhibition in human umbilical artery endothelial cells.

    PubMed

    Krause, Bernardo J; Hernandez, Cherie; Caniuguir, Andres; Vasquez-Devaud, Paola; Carrasco-Wong, Ivo; Uauy, Ricardo; Casanello, Paola

    2016-01-01

    Arginase-2 counteracts endothelial nitric oxide synthase (eNOS) activity in human endothelium, and its expression is negatively controlled by histone deacetylase (HDAC2). Conversely NO inhibits HDAC and previous studies suggest that arginase-2 is up-regulated by NO. We studied whether NO regulates arginase-2 expression in umbilical artery endothelial cells (HUAEC) increasing ARG2 promoter accessibility. HUAEC exposed to NOC-18 (NO donor, 1-100 μM, 0-24 h) showed an increase in arginase-2 but a decrease in eNOS mRNA levels in a time-dependent manner, with a maximal effect at 100 μM (24 h). Conversely NOS inhibition with L-NAME (100 μM) reduced arginase-2 mRNA and protein levels, an effect reverted by co-incubation with NOC-18. Treatment with TSA paralleled the effects of NO on arginase-2 and eNOS at mRNA and protein levels, with maximal effect at 10 μM. Co-incubation of NOC-18 (100 μM) with a sub-maximal concentration of TSA (1 μM) potentiated the increase in arginase-2 mRNA levels, whilst L-NAME prevented TSA-dependent arginase-2 induction. The effects on arginase-2 mRNA were paralleled by changes in chromatin accessibility, as well as increased levels of H3K9 and H4K12 acetylation, at ARG2 proximal (-579 to -367 and -280 to -73 bp from TSS) and core (-121 to +126 bp from TSS) promoter. Finally NO-dependent arginase-2 induction was prevented by pre-incubation for 10 min with the cysteine blocker MMTS (10 mM). These data showed for the first time that NO up-regulates arginase-2 expression in primary cultured human endothelial cells by an epigenetic-mediated mechanism increasing ARG2 promoter accessibility suggesting a negative regulatory loop for eNOS activity.

  4. Activation of protein kinase C inhibits potassium currents in cultured endothelial cells.

    PubMed

    Zhang, H; Weir, B; Daniel, E E

    1995-04-01

    The effect of protein kinase C on potassium channels in cultured endothelial cells was investigated by using whole-cell patch-clamp techniques. Activation of protein kinase C by phorbol 12-myristate 13-acetate (PMA) and phorbol 12,13-dibutyrate (PDBu), but not phorbol 12-monomyristate (PMM), an inactive analogue of phorbol esters, depressed an outward calcium-dependent potassium current. The inhibitory actions of PMA and PDBu could be reversed by the kinase inhibitor H-7. Cyclopiazonic acid, an inhibitor of the sarcoplasmic reticulum calcium pump, and LP-805, a novel vasodilator which also releases endothelium-derived relaxing factors, activated the outward calcium-dependent potassium conductance. PMA and PDBu, but not PMM, reduced the outward conductance induced by cyclopiazonic acid and LP-805. These effects of PMA and PDBu on potassium currents may be mediated either by phosphorylation of ion channels, or by decreasing intracellular calcium concentration.

  5. Estradiol inhibits vascular endothelial cells pro-inflammatory activation induced by C-reactive protein.

    PubMed

    Cossette, Émilie; Cloutier, Isabelle; Tardif, Kim; DonPierre, Geneviève; Tanguay, Jean-François

    2013-01-01

    In addition of being an important inflammatory biomarker and a risk factor for cardiovascular disease, much evidence indicates that the C-reactive protein (CRP) contributes to the atherosclerosis development process. This plasmatic protein synthesized by hepatocytes in response to inflammation and tissue injury induces pro-inflammatory molecules' expression by endothelial cells (ECs). Previous studies showed that the 17β-estradiol (E2) has beneficial effects on vascular cells by reducing in vitro pro-inflammatory molecules expressions in EC. Therefore, we hypothesize that E2 blocks or reduces CRP-mediated inflammatory responses by modulating endogenous production of CRP in EC and/or activation mechanisms. Using human aortic ECs (HAECs), we first evaluated CRP production by vascular EC and second demonstrated its self-induction. Indeed, recombinant human CRP stimulation induces a fivefold increase of CRP expression. A 1-h pre-treatment of E2 at a physiologic dose (10(-9 )M) leads to an important decrease of CRP production suggesting a partial blockage of its amplification loop mechanism. Furthermore, in HAEC, E2 reduces the secretion of the most potent agonist of CRP induction, the IL-6, by 21 %. E2 pre-treatment also decreased the expression of pro-inflammatory molecules IL-8, VCAM-1, and ICAM-1 induced by CRP and involved in leukocytes recruitment. In addition, we demonstrated that E2 could restore vascular endothelial growth factor-mediated EC migration response impaired by CRP suggesting another pro-angiogenic property of this hormone. These findings suggest that E2 can interfere with CRP pro-inflammatory effects via activation signals using its rapid, non-genomic pathway that may provide a new mechanism to improve vascular repair.

  6. eNOS-dependent S-nitrosylation of β-catenin prevents its association with TCF4 and inhibits proliferation of endothelial cells by Wnt3a.

    PubMed

    Zhang, Ying; Chidiac, Rony; Delisle, Chantal; Gratton, Jean-Philippe

    2017-03-20

    Nitric oxide (NO) produced by endothelial NO synthase (eNOS) modulates many functions in endothelial cells. S-nitrosylation (SNO) of cysteine residues on β-catenin by eNOS-derived NO has been shown to influence intercellular contacts between endothelial cells. However, the implication of SNO in the regulation of β-catenin transcriptional activity is ill-defined. Here we report that NO inhibits the transcriptional activity of β-catenin and endothelial cell proliferation induced by activation of Wnt/β-catenin signaling. Interestingly, induction by Wnt3a of β-catenin target genes, such as Axin2, is repressed in an eNOS-dependent manner by VEGF. We identify Cys466 of β-catenin as a target for SNO by eNOS-derived NO and as the critical residue for the repressive effects of NO on β-catenin transcriptional activity. Furthermore, we observed that Cys466 of β-catenin, located at the binding interface of the β-catenin/TCF4 transcriptional complex, is essential for disruption of this complex by NO. Importantly, Cys466 of β-catenin is necessary for the inhibitory effects of NO on Wnt3a-stimulated proliferation of endothelial cells. Thus our data define the mechanism responsible for the repressive effects of NO on the transcriptional activity of β-catenin and link eNOS-derived NO to the modulation by VEGF of Wnt/β-catenin-induced endothelial cell proliferation.

  7. Antioxidant treatment prevents serum deprivation- and TNF-α-induced endothelial dysfunction through the inhibition of NADPH oxidase 4 and the restoration of β-oxidation.

    PubMed

    Scioli, Maria Giovanna; Bielli, Alessandra; Agostinelli, Sara; Tarquini, Chiara; Arcuri, Gaetano; Ferlosio, Amedeo; Costanza, Gaetana; Doldo, Elena; Orlandi, Augusto

    2014-01-01

    Oxidative stress plays a pivotal role in the impaired endothelial function occurring in vascular diseases. Antioxidant strategies induce a clinical advantage in patients with endothelial dysfunction and atherosclerosis and protect from oxidative damage, but the underlying molecular mechanisms have been poorly evaluated. The aim of this study was to analyze the effects and mechanisms of action of antioxidant regimens on endothelial function. Antioxidant efficacy of N-acetylcysteine, ascorbic acid and propionyl-L-carnitine was evaluated in serum-deprived and TNF-α-stimulated human umbilical vein endothelial cells in vitro. Cell adhesion molecule (CAM) expression was evaluated by blot and real-time PCR, and inflammatory cytokine secretion was evaluated by ELISA; leukocyte adhesion and reactive oxygen species assays and NADPH oxidase 4 isoform (Nox4) expression analyses by blots were also performed. Antioxidant pretreatment restored serum-deprived and TNF-α-induced impaired mitochondrial β-oxidation by reducing flavin adenine dinucleotide level and counteracting increased CAM and Nox4 expression, leukocyte adhesion and inflammatory cytokine secretion. Specific inhibition by plumbagin and siNox4 prevented TNF-α- and serum deprivation-induced detrimental effects, confirming that endothelial oxidative stress and inflammation were Nox4 dependent. Our findings documented Nox4 as a main actor in oxidative stress-induced endothelial dysfunction and further clarify the molecular basis of antioxidant treatment efficacy. © 2014 S. Karger AG, Basel.

  8. Cyclosporin A induces hyperpermeability of the blood-brain barrier by inhibiting autocrine adrenomedullin-mediated up-regulation of endothelial barrier function.

    PubMed

    Dohgu, Shinya; Sumi, Noriko; Nishioku, Tsuyoshi; Takata, Fuyuko; Watanabe, Takuya; Naito, Mikihiko; Shuto, Hideki; Yamauchi, Atsushi; Kataoka, Yasufumi

    2010-10-10

    Cyclosporin A, a potent immunosuppressant, can often produce neurotoxicity in patients, although its penetration into the brain is restricted by the blood-brain barrier (BBB). Brain pericytes and astrocytes, which are periendothelial accessory structures of the BBB, can be involved in cyclosporin A-induced BBB disruption. However, the mechanism by which cyclosporin A causes BBB dysfunction remains unknown. Here, we show that in rodent brain endothelial cells, cyclosporin A decreased transendothelial electrical resistance (TEER) by inhibiting intracellular signal transduction downstream of adrenomedullin, an autocrine regulator of BBB function. Cyclosporin A stimulated adrenomedullin release from brain endothelial cells, but did not affect binding of adrenomedullin to its receptors. This cyclosporin A-induced decrease in TEER was attenuated by exogenous addition of adrenomedullin. Cyclosporin A dose-dependently decreased the total cAMP concentration in brain endothelial cells. A combination of cyclosporin A (1microM) with an adenylyl cyclase inhibitor, 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ22536; 10microM), or a protein kinase A (PKA) inhibitor, N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride (H89; 1microM), markedly increased sodium fluorescein permeability in brain endothelial cells, whereas each drug alone had no effect. Thus, these data suggest that cyclosporin A inhibits the adenylyl cyclase/cyclic AMP/PKA signaling pathway activated by adrenomedullin, leading to impairment of brain endothelial barrier function. Copyright 2010. Published by Elsevier B.V.

  9. The aryl hydrocarbon receptor (AhR) inhibits vanadate-induced vascular endothelial growth factor (VEGF) production in TRAMP prostates

    PubMed Central

    Fritz, Wayne A.; Lin, Tien-Min; Peterson, Richard E.

    2008-01-01

    Hypoxia-inducible factor-1 alpha (HIF-1α) and aryl hydrocarbon receptor nuclear translocator (ARNT) are basic helix-loop-helix/per-arnt-sim (PAS) family transcription factors. During angiogenesis and tumor growth, HIF-1α dimerizes with ARNT, inducing expression of many genes, including vascular endothelial growth factor (VEGF). ARNT also dimerizes with the aryl hydrocarbon receptor (AhR). AhR-null (Ahr−/−) transgenic adenocarcinoma of the mouse prostate (TRAMP) mice develop prostate tumors with greater frequency than AhR wild-type (Ahr+/+) TRAMP mice, even though prevalence of prostate epithelial hyperplasia is not inhibited. This suggests that Ahr inhibits prostate carcinogenesis. In TRAMP mice, prostatic epithelial hyperplasia results in stabilized HIF-1α, inducing expression of VEGF, a prerequisite for tumor growth and angiogenesis. Since ARNT is a common dimerization partner of AhR and HIF-1α, we hypothesized that the AhR inhibits prostate tumor formation by competing with HIF-1α for ARNT, thereby limiting VEGF production. Prostates from Ahr+/+, Ahr+/− and Ahr−/− C57BL/6J TRAMP mice were cultured in the presence of graded concentrations of vanadate, an inducer of VEGF through the HIF-1α–ARNT pathway. Vanadate induced VEGF protein in a dose-dependent fashion in Ahr+/− and Ahr−/− TRAMP cultures, but not in Ahr+/+ cultures. However, vanadate induced upstream proteins in the phosphatidylinositol 3-kinase-signaling cascade to a similar extent in TRAMPs of each Ahr genotype, evidenced by v-akt murine thymoma viral oncogene homolog (Akt) phosphorylation. These findings suggest that AhR sequesters ARNT, decreasing interaction with HIF-1α reducing VEGF production. Since VEGF is required for tumor vascularization and growth, these studies further suggest that reduction in VEGF correlates with inhibited prostate carcinogenesis in Ahr+/+ TRAMP mice. PMID:18359762

  10. Calcium Dobesilate Inhibits the Alterations in Tight Junction Proteins and Leukocyte Adhesion to Retinal Endothelial Cells Induced by Diabetes

    PubMed Central

    Leal, Ermelindo C.; Martins, João; Voabil, Paula; Liberal, Joana; Chiavaroli, Carlo; Bauer, Jacques; Cunha-Vaz, José; Ambrósio, António F.

    2010-01-01

    OBJECTIVE Calcium dobesilate (CaD) has been used in the treatment of diabetic retinopathy in the last decades, but its mechanisms of action are not elucidated. CaD is able to correct the excessive vascular permeability in the retina of diabetic patients and in experimental diabetes. We investigated the molecular and cellular mechanisms underlying the protective effects of CaD against the increase in blood–retinal barrier (BRB) permeability induced by diabetes. RESEARCH DESIGN AND METHODS Wistar rats were divided into three groups: controls, streptozotocin-induced diabetic rats, and diabetic rats treated with CaD. The BRB breakdown was evaluated using Evans blue. The content or distribution of tight junction proteins (occludin, claudin-5, and zonula occluden-1 [ZO-1]), intercellular adhesion molecule-1 (ICAM-1), and p38 mitogen-activated protein kinase (p38 MAPK) was evaluated by Western blotting and immunohistochemistry. Leukocyte adhesion was evaluated in retinal vessels and in vitro. Oxidative stress was evaluated by the detection of oxidized carbonyls and tyrosine nitration. NF-κB activation was measured by enzyme-linked immunosorbent assay. RESULTS Diabetes increased the BRB permeability and retinal thickness. Diabetes also decreased occludin and claudin-5 levels and altered the distribution of ZO-1 and occludin in retinal vessels. These changes were inhibited by CaD treatment. CaD also inhibited the increase in leukocyte adhesion to retinal vessels or endothelial cells and in ICAM-1 levels, induced by diabetes or elevated glucose. Moreover, CaD decreased oxidative stress and p38 MAPK and NF-κB activation caused by diabetes. CONCLUSIONS CaD prevents the BRB breakdown induced by diabetes, by restoring tight junction protein levels and organization and decreasing leukocyte adhesion to retinal vessels. The protective effects of CaD are likely to involve the inhibition of p38 MAPK and NF-κB activation, possibly through the inhibition of oxidative

  11. Jolkinolide A and Jolkinolide B Inhibit Proliferation of A549 Cells and Activity of Human Umbilical Vein Endothelial Cells.

    PubMed

    Shen, Lei; Zhang, Shan-Qiang; Liu, Lei; Sun, Yu; Wu, Yu-Xuan; Xie, Li-Ping; Liu, Ji-Cheng

    2017-01-14

    BACKGROUND Jolkinolide A (JA) and Jolkinolide B (JB) are diterpenoids extracted from the roots of Euphorbia fischeriana Steud and have been shown to have anti-tumor activity. However, their effects on the ability of tumor cells to invade blood vessels and metastasize remain largely unknown. Investigations into the effects of JA and JB on the angiogenesis of tumor tissues may facilitate the identification of new natural drugs with anti-tumor growth and metastasis activities. MATERIAL AND METHODS We used different concentrations of JA and JB (20 μg/ml, 40 μg/ml, 60 μg/ml, 80 μg/ml, and 100 μg/ml) to stimulate A549 cells and then studied the effects on the growth and metastasis of lung cancers. In addition, we used conditional media from A549 cells (A549-CM) stimulated by either JA or JB in different concentrations to culture human umbilical vein endothelial cells (HUVECs). RESULTS We found that both JA and JB significantly inhibited the Akt-STAT3-mTOR signaling pathway and reduced the expression of VEGF in A549 cells, but JB exhibited more significant inhibitory effects than JA. The JB-stimulated A549 cell conditional media had a greater inhibitory effect on the proliferation and migration of HUVECs than did the conditional media of JA-stimulated A549 cells. This effect gradually increased with increasing concentrations of either type of Jolkinolide. CONCLUSIONS Our results suggest that JA and JB inhibited VEGF expression in A549 cells through the inhibition of the Akt-STAT3-mTOR signaling pathway, and directly inhibited the proliferation and migration of HUVECs. These findings are of great significance for the development of new plant-derived chemotherapy agents for the treatment of cancer.

  12. Inhibition of Myeloperoxidase- and Neutrophil-Mediated Hypochlorous Acid Formation in Vitro and Endothelial Cell Injury by (-)-Epigallocatechin Gallate.

    PubMed

    Tian, Rong; Ding, Yun; Peng, Yi-Yuan; Lu, Naihao

    2017-04-10

    Myeloperoxidase (MPO) plays important roles in various diseases through its unique chlorinating activity to catalyze excess hypochlorous acid (HOCl) formation. Epidemiological studies indicate an inverse correlation between plant polyphenol consumption and the incidence of cardiovascular diseases. Here we showed that (-)-epigallocatechin gallate (EGCG), the main flavonoid present in green tea, dose-dependently inhibited MPO-mediated HOCl formation in vitro (chlorinating activities of MPO: 50.2 ± 5.7% for 20 μM EGCG versus 100 ± 5.6% for control, P < 0.01). UV-vis spectral and docking studies indicated that EGCG bound to the active site (heme) of MPO and resulted in the accumulation of compound II, which was unable to produce HOCl. This flavonoid also effectively inhibited HOCl generation in activated neutrophils (HOCl formation: 65.0 ± 5.6% for 20 μM EGCG versus 100 ± 6.2% for control, P < 0.01) without influencing MPO and Nox2 release and superoxide formation, suggesting that EGCG specifically inhibited MPO but not NADPH oxidase activity in activated neutrophils. Moreover, EGCG inhibited MPO (or neutrophil)-mediated HOCl formation in human umbilical vein endothelial cells (HUVEC) culture and accordingly protected HUVEC from MPO (or neutrophil)-induced injury (P < 0.05, all cases), although it did not induce cytotoxicity to HUVEC (P > 0.05, all cases). Our results indicate that dietary EGCG is an effective and specific inhibitor of MPO activity and may participate in the regulation of immune responses at inflammatory sites.

  13. Jolkinolide A and Jolkinolide B Inhibit Proliferation of A549 Cells and Activity of Human Umbilical Vein Endothelial Cells

    PubMed Central

    Shen, Lei; Zhang, Shan-Qiang; Liu, Lei; Sun, Yu; Wu, Yu-Xuan; Xie, Li-Ping; Liu, Ji-Cheng

    2017-01-01

    Background Jolkinolide A (JA) and Jolkinolide B (JB) are diterpenoids extracted from the roots of Euphorbia fischeriana Steud and have been shown to have anti-tumor activity. However, their effects on the ability of tumor cells to invade blood vessels and metastasize remain largely unknown. Investigations into the effects of JA and JB on the angiogenesis of tumor tissues may facilitate the identification of new natural drugs with anti-tumor growth and metastasis activities. Material/Methods We used different concentrations of JA and JB (20 μg/ml, 40 μg/ml, 60 μg/ml, 80 μg/ml, and 100 μg/ml) to stimulate A549 cells and then studied the effects on the growth and metastasis of lung cancers. In addition, we used conditional media from A549 cells (A549-CM) stimulated by either JA or JB in different concentrations to culture human umbilical vein endothelial cells (HUVECs). Results We found that both JA and JB significantly inhibited the Akt-STAT3-mTOR signaling pathway and reduced the expression of VEGF in A549 cells, but JB exhibited more significant inhibitory effects than JA. The JB-stimulated A549 cell conditional media had a greater inhibitory effect on the proliferation and migration of HUVECs than did the conditional media of JA-stimulated A549 cells. This effect gradually increased with increasing concentrations of either type of Jolkinolide. Conclusions Our results suggest that JA and JB inhibited VEGF expression in A549 cells through the inhibition of the Akt-STAT3-mTOR signaling pathway, and directly inhibited the proliferation and migration of HUVECs. These findings are of great significance for the development of new plant-derived chemotherapy agents for the treatment of cancer. PMID:28087861

  14. Ilexgenin A inhibits endoplasmic reticulum stress and ameliorates endothelial dysfunction via suppression of TXNIP/NLRP3 inflammasome activation in an AMPK dependent manner.

    PubMed

    Li, Yi; Yang, Jie; Chen, Mei-Hong; Wang, Qiang; Qin, Min-Jian; Zhang, Tong; Chen, Xiao-Qing; Liu, Bao-Lin; Wen, Xiao-Dong

    2015-09-01

    Ilexgenin A is a natural triterpenoid with beneficial effects on lipid disorders. This study aimed to investigate the effects of ilexgenin A on endothelial homeostasis and its mechanisms. Palmitate (PA) stimulation induced endoplasmic reticulum stress (ER stress) and subsequent thioredoxin-interacting protein (TXNIP)/NLRP3 inflammasome activation in endothelial cells, leading to endothelial dysfunction. Ilexgenin A enhanced LKB1-dependent AMPK activity and improved ER stress by suppression of ROS-associated TXNIP induction. However, these effects were blocked by knockdown of AMPKα, indicating AMPK is essential for its action in suppression of ER stress. Meanwhile, ilexgenin A inhibited NLRP3 inflammasome activation by down-regulation of NLRP3 and cleaved caspase-1 induction, and thereby reduced IL-1β secretion. It also inhibited inflammation and apoptosis exposed to PA insult. Consistent with these results in endothelial cells, ilexgenin A attenuated ER stress and restored the loss of eNOS activity in vascular endothelium, and thereby improved endothelium-dependent vasodilation in rat aorta. A further analysis in high-fat fed mice showed that oral administration of ilexgenin A blocked ER stress/NLRP3 activation with reduced ROS generation and increased NO production in vascular endothelium, well confirming the beneficial effect of ilexgenin A on endothelial homeostasis in vivo. Taken together, these results show ER stress-associated TXNIP/NLRP3 inflammasome activation was responsible for endothelial dysfunction and ilexgenin A ameliorated endothelial dysfunction by suppressing ER-stress and TXNIP/NLRP3 inflammasome activation with a regulation of AMPK. This finding suggests that the application of ilexgenin A is useful in the management of cardiovascular diseases in obesity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. GPR55 agonist lysophosphatidylinositol and lysophosphatidylcholine inhibit endothelial cell hyperpolarization via GPR-independent suppression of Na(+)-Ca(2+) exchanger and endoplasmic reticulum Ca(2+) refilling.

    PubMed

    Bondarenko, Alexander I; Montecucco, Fabrizio; Panasiuk, Olga; Sagach, Vadim; Sidoryak, Nataliya; Brandt, Karim J; Mach, François

    2017-02-01

    Lysophosphatidylinositol (LPI) and lysophosphatidylcholine (LPC) are lipid signaling molecules that induce endothelium-dependent vasodilation. In addition, LPC suppresses acetylcholine (Ach)-induced responses. We aimed to determine the influence of LPC and LPI on hyperpolarizing responses in vitro and in situ endothelial cells (EC) and identify the underlying mechanisms. Using patch-clamp method, we show that LPI and LPC inhibit EC hyperpolarization to histamine and suppress Na(+)/Ca(2+) exchanged (NCX) currents in a concentration-dependent manner. The inhibition is non-mode-specific and unaffected by intracellular GDPβS infusion and tempol, a superoxide dismutase mimetic. In excised mouse aorta, LPI strongly inhibits the sustained and the peak endothelial hyperpolarization induced by Ach, but not by SKA-31, an opener of Ca(2+)-dependent K(+) channels of intermediate and small conductance. The hyperpolarizing responses to consecutive histamine applications are strongly reduced by NCX inhibition. In a Ca(2+)-re-addition protocol, bepridil, a NCX inhibitor, and KB-R7943, a blocker of reversed NCX, inhibit the hyperpolarizing responses to Ca(2+)-re-addition following Ca(2+) stores depletion. These finding indicate that LPC and LPI inhibit endothelial hyperpolarization to Ach and histamine independently of G-protein coupled receptors and superoxide anions. Reversed NCX is critical for ER Ca(2+) refilling in EC. The inhibition of NCX by LPI and LPC underlies diminished endothelium-dependent responses and endothelial dysfunction accompanied by increased levels of these lipids in the blood. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Glucocorticoid-Mediated Inhibition of Angiogenic Changes in Human Endothelial Cells Is Not Caused by Reductions in Cell Proliferation or Migration

    PubMed Central

    Logie, James J.; Ali, Sadaf; Marshall, Kathryn M.; Heck, Margarete M. S.; Walker, Brian R.; Hadoke, Patrick W. F.

    2010-01-01

    Background Glucocorticoid-mediated inhibition of angiogenesis is important in physiology, pathophysiology and therapy. However, the mechanisms through which glucocorticoids inhibit growth of new blood vessels have not been established. This study addresses the hypothesis that physiological levels of glucocorticoids inhibit angiogenesis by directly preventing tube formation by endothelial cells. Methodology/Principal Findings Cultured human umbilical vein (HUVEC) and aortic (HAoEC) endothelial cells were used to determine the influence of glucocorticoids on tube-like structure (TLS) formation, and on cellular proliferation (5-bromo-2′-deoxyuridine (BrdU) incorporation), viability (ATP production) and migration (Boyden chambers). Dexamethasone or cortisol (at physiological concentrations) inhibited both basal and prostaglandin F2α (PGF2α)-induced and vascular endothelial growth factor (VEGF) stimulated TLS formation in endothelial cells (ECs) cultured on Matrigel, effects which were blocked with the glucocorticoid receptor antagonist RU38486. Glucocorticoids had no effect on EC viability, migration or proliferation. Time-lapse imaging showed that cortisol blocked VEGF-stimulated cytoskeletal reorganisation and initialisation of tube formation. Real time PCR suggested that increased expression of thrombospodin-1 contributed to glucocorticoid-mediated inhibition of TLS formation. Conclusions/Significance We conclude that glucocorticoids interact directly with glucocorticoid receptors on vascular ECs to inhibit TLS formation. This action, which was conserved in ECs from two distinct vascular territories, was due to alterations in cell morphology rather than inhibition of EC viability, migration or proliferation and may be mediated in part by induction of thrombospodin-1. These findings provide important insights into the anti-angiogenic action of endogenous glucocorticoids in health and disease. PMID:21217824

  17. Lung endothelial barrier protection by resveratrol involves inhibition of HMGB1 release and HMGB1-induced mitochondrial oxidative damage via an Nrf2-dependent mechanism.

    PubMed

    Dong, Wen-Wen; Liu, Yu-Jian; Lv, Zhou; Mao, Yan-Fei; Wang, Ying-Wei; Zhu, Xiao-Yan; Jiang, Lai

    2015-11-01

    High-mobility group box 1 (HMGB1) contributes to lung vascular hyperpermeability during ventilator-induced lung injury. We aimed to determine whether the natural antioxidant resveratrol protected against HMGB1-induced endothelial hyperpermeability both in vitro and in vivo. We found that HMGB1 decreased vascular endothelial (VE)-cadherin expression and increased endothelial permeability, leading to mitochondrial oxidative damage in primary cultured mouse lung vascular endothelial cells (MLVECs). Both the mitochondrial superoxide dismutase 2 mimetic MnTBAP and resveratrol blocked HMGB1-induced mitochondrial oxidative damage, VE-cadherin downregulation, and endothelial hyperpermeability. In in vivo studies, anesthetized male ICR mice were ventilated for 4h using low tidal volume (6 ml/kg) or high tidal volume (HVT; 30 ml/kg) ventilation. The mice were injected intraperitoneally with resveratrol immediately before the onset of ventilation. We found that resveratrol attenuated HVT-associated lung vascular hyperpermeability and HMGB1 production. HVT caused a significant increase in nuclear factor-erythroid 2-related factor 2 (Nrf2) nuclear translocation and Nrf2 target gene expression in lung tissues, which was further enhanced by resveratrol treatment. HMGB1 had no effect on Nrf2 activation, whereas resveratrol treatment activated the Nrf2 signaling pathway in HMGB1-treated MLVECs. Moreover, Nrf2 knockdown reversed the inhibitory effects of resveratrol on HMGB1-induced mitochondrial oxidative damage and endothelial hyperpermeability. The inhibitory effect of resveratrol on cyclic stretch-induced HMGB1 mRNA expression in primary cultured MLVECs was also abolished by Nrf2 knockdown. In summary, this study demonstrates that resveratrol protects against lung endothelial barrier dysfunction initiated by HVT. Lung endothelial barrier protection by resveratrol involves inhibition of mechanical stretch-induced HMGB1 release and HMGB1-induced mitochondrial oxidative damage

  18. Induction of heme oxygenase 1 by arsenite inhibits cytokine-induced monocyte adhesion to human endothelial cells

    SciTech Connect

    Sun Xi; Pi Jingbo; Liu Wenlan; Hudson, Laurie G.; Liu Kejian; Feng Changjian

    2009-04-15

    Heme oxygenase-1 (HO-1) is an oxidative stress responsive gene upregulated by various physiological and exogenous stimuli. Arsenite, as an oxidative stressor, is a potent inducer of HO-1 in human and rodent cells. In this study, we investigated the mechanistic role of arsenite-induced HO-1 in modulating tumor necrosis factor {alpha} (TNF-{alpha}) induced monocyte adhesion to human umbilical vein endothelial cells (HUVEC). Arsenite pretreatment, which upregulated HO-1 in a time- and concentration-dependent manner, inhibited TNF-{alpha}-induced monocyte adhesion to HUVEC and intercellular adhesion molecule 1 protein expression by 50% and 40%, respectively. Importantly, knockdown of HO-1 by small interfering RNA abolished the arsenite-induced inhibitory effects. These results indicate that induction of HO-1 by arsenite inhibits the cytokine-induced monocyte adhesion to HUVEC by suppressing adhesion molecule expression. These findings established an important mechanistic link between the functional monocyte adhesion properties of HUVEC and the induction of HO-1 by arsenite.

  19. Inhibition of TNF-alpha induced cell death in human umbilical vein endothelial cells and Jurkat cells by protocatechuic acid.

    PubMed

    Zhou-Stache, J; Buettner, R; Artmann, G; Mittermayer, C; Bosserhoff, A K

    2002-11-01

    The Chinese herb radix Salviae miltiorrhizae (RSM) is used in traditional Chinese medicine as a treatment for cardiovascular and cerebrovascular diseases. Several components of the plant extract from salvia mitorrhiza bunge have been determined previously, one of which is protocatechuic acid (PAC). It has been found, in the study, that PAC inhibited TNF-alpha-induced cell death of human umbilical vein endothelial cells (HUVECs) and Jurkat cells in a concentration of 100 microM when applied 2 h prior to TNF-alpha exposure. Molecular studies revealed that PAC activated NF-kappaB with a maximum effect after 30 min of treatment. Inhibition of NF-kappaB action by MG132 and NF-kappaB inhibitory peptide suppressed the cell-protective effect of PAC. Further, degradation of IkBalpha occurred in response to PAC treatment. The results provide evidence that activation of NF-kappaB plays an important role in mediating the cell-protecting effect of PAC on HUVECs and Jurkat cells. Further studies are required to test whether PAC, a component of radix salviae miltiorrhizae, could be useful in preventing in vivo cell death resulting from cardiovascular or cerebrovascular diseases.

  20. Salmon-derived thrombin inhibits development of chronic pain through an endothelial barrier protective mechanism dependent on APC

    PubMed Central

    Smith, Jenell R; Galie, Peter A; Slochower, David R; Weisshaar, Christine L.; Janmey, Paul A; Winkelstein, Beth A

    2015-01-01

    Many neurological disorders are initiated by blood-brain barrier breakdown, which potentiates spinal neuroinflammation and neurodegeneration. Peripheral neuropathic injuries are known to disrupt the blood-spinal cord barrier (BSCB) and to potentiate inflammation. But, it is not known whether BSCB breakdown facilitates pain development. In this study, a neural compression model in the rat was used to evaluate relationships among BSCB permeability, inflammation and pain-related behaviors. BSCB permeability increases transiently only after injury that induces mechanical hyperalgesia, which correlates with serum concentrations of pro-inflammatory cytokines, IL-7, IL-12, IL-1α and TNF-α. Mammalian thrombin dually regulates vascular permeability through PAR1 and activated protein C (APC). Since thrombin protects vascular integrity through APC, directing its affinity towards protein C, while still promoting coagulation, might be an ideal treatment for BSCB-disrupting disorders. Salmon thrombin, which prevents the development of mechanical allodynia, also prevents BSCB breakdown after neural injury and actively inhibits TNF-α-induced endothelial permeability in vitro, which is not evident the case for human thrombin. Salmon thrombin’s production of APC faster than human thrombin is confirmed using a fluorogenic assay and APC is shown to inhibit BSCB breakdown and pain-related behaviors similar to salmon thrombin. Together, these studies highlight the impact of BSCB on pain and establish salmon thrombin as an effective blocker of BSCB, and resulting nociception, through its preferential affinity for protein C. PMID:26708087

  1. Thiazolidinediones enhance vascular endothelial growth factor expression and induce cell growth inhibition in non-small-cell lung cancer cells

    PubMed Central

    2010-01-01

    Background It is known that thiazolidinediones are involved in regulating the expression of various genes, including the vascular endothelial growth factor (VEGF) gene via peroxisome proliferator-activated receptor γ (PPARγ); VEGF is a prognostic biomarker for non-small-cell lung cancer (NSCLC). Methods In this study, we investigated the effects of troglitazone and ciglitazone on the mRNA expression of VEGF and its receptors in human NSCLC cell lines, RERF-LC-AI, SK-MES-1, PC-14, and A549. These mRNA expressions were evaluated by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis. We also studied the effect of Je-11, a VEGF inhibitor, on the growth of these cells. Results In NSCLC cells, thiazolidinediones increased the mRNA expression of VEGF and neuropilin-1, but not that of other receptors such as fms-like tyrosine kinase and kinase insert domain receptor-1. Furthermore, the PPARγ antagonist GW9662 completely reversed this thiazolidinedione-induced increase in VEGF expression. Furthermore, the addition of VEGF inhibitors into the culture medium resulted in the reversal of thiazolidinedione-induced growth inhibition. Conclusions Our results indicated that thiazolidinediones enhance VEGF and neuropilin-1 expression and induce the inhibition of cell growth. We propose the existence of a pathway for arresting cell growth that involves the interaction of thiazolidinedione-induced VEGF and neuropilin-1 in NSCLC. PMID:20214829

  2. Inhibition of Insulin Signaling in Endothelial Cells by Protein Kinase C-induced Phosphorylation of p85 Subunit of Phosphatidylinositol 3-Kinase (PI3K)*

    PubMed Central

    Maeno, Yasuhiro; Li, Qian; Park, Kyoungmin; Rask-Madsen, Christian; Gao, Benbo; Matsumoto, Motonobu; Liu, Yingjie; Wu, I-Hsien; White, Morris F.; Feener, Edward P.; King, George L.

    2012-01-01

    The regulation of endothelial function by insulin is consistently abnormal in insulin-resistant states and diabetes. Protein kinase C (PKC) activation has been reported to inhibit insulin signaling selectively in endothelial cells via the insulin receptor substrate/PI3K/Akt pathway to reduce the activation of endothelial nitric-oxide synthase (eNOS). In this study, it was observed that PKC activation differentially inhibited insulin receptor substrate 1/2 (IRS1/2) signaling of insulin's activation of PI3K/eNOS by decreasing only tyrosine phosphorylation of IRS2. In addition, PKC activation, by general activator and specifically by angiotensin II, increased the phosphorylation of p85/PI3K, which decreases its association with IRS1 and activation. Thr-86 of p85/PI3K was identified to be phosphorylated by PKC activation and confirmed to affect IRS1-mediated activation of Akt/eNOS by insulin and VEGF using a deletion mutant of the Thr-86 region of p85/PI3K. Thus, PKC and angiotensin-induced phosphorylation of Thr-86 of p85/PI3K may partially inhibit the activation of PI3K/eNOS by multiple cytokines and contribute to endothelial dysfunction in metabolic disorders. PMID:22158866

  3. Schlafen 1 inhibits the proliferation and tube formation of endothelial progenitor cells.

    PubMed

    Kuang, Chun-yan; Yang, Tian-he; Zhang, Yang; Zhang, Lu; Wu, Qiang

    2014-01-01

    Endothelial progenitor cells (EPCs) are the major source of cells that restore the endothelium during reendothelialization. This study was designed to investigate whether Schlafen 1 (Slfn1) has an effect on the proliferation and tube formation of EPCs in vivo. Slfn1 was expressed in rat EPCs. The overexpression of Slfn1 suppressed the proliferation and tube formation of EPCs; conversely, the knockdown of Slfn1 by shRNA promoted the proliferation and tube formation of EPCs. Furthermore, when Slfn1 was overexpressed, the EPCs were arrested in the G1 phase of the cell cycle. In contrast, when Slfn1 was knocked down, the EPCs progressed into the S phase of the cell cycle. Additionally, the overexpression of Slfn1 decreased the expression of Cyclin D1, whereas the knockdown of Slfn1 increased the expression of Cyclin D1; these findings suggest that Cyclin D1 is downstream of Slfn1 in Slfn1-mediated EPC proliferation. Taken together, these results indicate a key role for Slfn1 in the regulation of EPC biological behavior, which may provide a new target for the use of EPCs during reendothelialization.

  4. Schlafen 1 Inhibits the Proliferation and Tube Formation of Endothelial Progenitor Cells

    PubMed Central

    Kuang, Chun-yan; Yang, Tian-he; Zhang, Yang

    2014-01-01

    Endothelial progenitor cells (EPCs) are the major source of cells that restore the endothelium during reendothelialization. This study was designed to investigate whether Schlafen 1 (Slfn1) has an effect on the proliferation and tube formation of EPCs in vivo. Slfn1 was expressed in rat EPCs. The overexpression of Slfn1 suppressed the proliferation and tube formation of EPCs; conversely, the knockdown of Slfn1 by shRNA promoted the proliferation and tube formation of EPCs. Furthermore, when Slfn1 was overexpressed, the EPCs were arrested in the G1 phase of the cell cycle. In contrast, when Slfn1 was knocked down, the EPCs progressed into the S phase of the cell cycle. Additionally, the overexpression of Slfn1 decreased the expression of Cyclin D1, whereas the knockdown of Slfn1 increased the expression of Cyclin D1; these findings suggest that Cyclin D1 is downstream of Slfn1 in Slfn1-mediated EPC proliferation. Taken together, these results indicate a key role for Slfn1 in the regulation of EPC biological behavior, which may provide a new target for the use of EPCs during reendothelialization. PMID:25329797

  5. Vasopeptidase inhibition improves insulin sensitivity and endothelial function in the JCR:LA-cp rat.

    PubMed

    Russell, James C; Kelly, Sandra E; Schäfer, Stefan

    2004-08-01

    The insulin-resistant, hyperinsulinemic, normoglycemic, and obese JCR:LA-cp rat was used to study the effects of ramipril (an ACE inhibitor) and AVE7688 (a dual inhibitor of ACE and neutral endopeptidases) on insulin sensitivity and vascular function. Both compounds reduced the surge of plasma insulin in a meal tolerance test by approximately 50%. Ramipril had no effect on acetylcholine-induced relaxation but increased the sensitivity to sodium nitroprus-side at low concentrations. AVE7688 significantly reduced the EC50 for acetylcholine to relax phenylephrine-contracted aortic rings. None of the compounds affected the baseline coronary flow and reactive hyperemia. Coronary flow response to bradykinin in AVE7688- and ramipril-treated rat hearts showed a significantly lower EC50 than in control rats. Maximum flow rate was not different between groups. In summary, both ramipril and AVE7688 had significant hypoinsulinemic and insulin-sensitizing effects. Whereas ramipril had limited vascular effects, AVE7688 had more marked beneficial vascular effects, probably of endothelial origin and possibly related to lowered insulin levels.

  6. Inhibition of Murine Pulmonary Microvascular Endothelial Cell Apoptosis Promotes Recovery of Barrier Function under Septic Conditions

    PubMed Central

    Wang, Lefeng; Mehta, Sanjay; Brock, Michael

    2017-01-01

    Sepsis is characterized by injury of the pulmonary microvasculature and the pulmonary microvascular endothelial cells (PMVEC), leading to barrier dysfunction and acute respiratory distress syndrome (ARDS). Our recent work identified a strong correlation between PMVEC apoptosis and microvascular leak in septic mice in vivo, but the specific role of apoptosis in septic PMVEC barrier dysfunction remains unclear. Thus, we hypothesize that PMVEC apoptosis is likely required for PMVEC barrier dysfunction under septic conditions in vitro. Septic stimulation (mixture of tumour necrosis factor α, interleukin 1β, and interferon γ [cytomix]) of isolated murine PMVEC resulted in a significant loss of barrier function as early as 4 h after stimulation, which persisted until 24 h. PMVEC apoptosis, as reflected by caspase activation, DNA fragmentation, and loss of membrane polarity, was first apparent at 8 h after cytomix. Pretreatment of PMVEC with the pan-caspase inhibitor Q-VD significantly decreased septic PMVEC apoptosis and was associated with reestablishment of PMVEC barrier function at 16 and 24 h after stimulation but had no effect on septic PMVEC barrier dysfunction over the first 8 h. Collectively, our data suggest that early septic murine PMVEC barrier dysfunction driven by proinflammatory cytokines is not mediated through apoptosis, but PMVEC apoptosis contributes to late septic PMVEC barrier dysfunction. PMID:28250575

  7. Temsirolimus Inhibits Proliferation and Migration in Retinal Pigment Epithelial and Endothelial Cells via mTOR Inhibition and Decreases VEGF and PDGF Expression

    PubMed Central

    Siedlecki, Jakob; Haritoglou, Christos; Kampik, Anselm; Kernt, Marcus

    2014-01-01

    Due to their high prevalence, retinal vascular diseases including age related macular degeneration (AMD), retinal vein occlusions (RVO), diabetic retinopathy (DR) and diabetic macular edema have been major therapeutic targets over the last years. The pathogenesis of these diseases is complex and yet not fully understood. However, increased proliferation, migration and angiogenesis are characteristic cellular features in almost every retinal vascular disease. The introduction of vascular endothelial growth factor (VEGF) binding intravitreal treatment strategies has led to great advances in the therapy of these diseases. While the predominant part of affected patients benefits from the specific binding of VEGF by administering an anti-VEGF antibody into the vitreous cavity, a small number of non-responders exist and alternative or additional therapeutic strategies should therefore be evaluated. The mammalian target of rapamycin (mTOR) is a central signaling pathway that eventually triggers up-regulation of cellular proliferation, migration and survival and has been identified to play a key role in angiogenesis. In the present study we were able to show that both retinal pigment epithelial (RPE) cells as wells as human umbilical vein endothelial cells (HUVEC) are inhibited in proliferating and migrating after treatment with temsirolimus in non-toxic concentrations. Previous studies suggest that the production of VEGF, platelet derived growth factor (PDGF) and other important cytokines is not only triggered by hypoxia but also by mTOR itself. Our results indicate that temsirolimus decreases VEGF and PDGF expression on RNA and protein levels significantly. We therefore believe that the mTOR inhibitor temsirolimus might be a promising drug in the future and it seems worthwhile to evaluate complementary therapeutic effects with anti-VEGF drugs for patients not profiting from mono anti-VEGF therapy alone. PMID:24586308

  8. Chimeric SOD2/3 inhibits at the endothelial-neutrophil interface to limit vascular dysfunction in ischemia-reperfusion.

    PubMed

    Bonder, Claudine S; Knight, Derrice; Hernandez-Saavedra, Daniel; McCord, Joe M; Kubes, Paul

    2004-09-01

    After an ischemic episode, reperfusion causes profound oxidative stress in the vasculature of the afflicted tissue/organ. The dysregulated accumulation of reactive oxygen species (ROS), such as superoxide, has been closely linked to the production and release of proinflammatory mediators, a profound increase in adhesion molecule expression by the vascular endothelium, and infiltration of neutrophils during ischemia-reperfusion (I/R). Superoxide dismutase (SOD) has been shown to protect tissues and organs against I/R-induced injury; however, the drug had to be continuously perfused or kidneys had to be occluded to prevent clearance. We used intravital microscopy, a system that allowed us to visualize neutrophil-endothelial interactions within the mesenteric postcapillary venules of cats subjected to I/R and tested the hypothesis that I/R-induced neutrophil recruitment was inhibited by treatment with SOD2/3. SOD2/3 is a chimeric fusion gene product that contains the mature SOD2 as well as the COOH-terminal "tail" of SOD3 and, unlike the three naturally occurring SODs (SOD1, SOD2, and SOD3), which bear a net negative charge at pH 7.4, SOD2/3 is positively charged and physiologically stable. Our results suggest that not only does SOD2/3 have a much greater efficacy in vivo than the native human SOD2, but its administration prevents I/R-induced neutrophil-endothelial cell interactions and microvascular dysfunction. Moreover, our data support the hypothesis that reactive oxidants mediate I/R-induced injury and that the chimeric recombinant SOD2/3 has the potential to be a therapeutic agent against this debilitating illness.

  9. Inhibition of Plasmodium falciparum Field Isolates-Mediated Endothelial Cell Apoptosis by Fasudil: Therapeutic Implications for Severe Malaria

    PubMed Central

    Zang-Edou, Estelle S.; Bisvigou, Ulrick; Taoufiq, Zacharie; Lékoulou, Faustin; Lékana-Douki, Jean Bernard; Traoré, Yves; Mazier, Dominique; Touré-Ndouo, Fousseyni S.

    2010-01-01

    Plasmodium falciparum infection can abruptly progress to severe malaria, a life-threatening complication resulting from sequestration of parasitized red blood cells (PRBC) in the microvasculature of various organs such as the brain and lungs. PRBC adhesion can induce endothelial cell (EC) activation and apoptosis, thereby disrupting the blood-brain barrier. Moreover, hemozoin, the malarial pigment, induces the erythroid precursor apoptosis. Despite the current efficiency of antimalarial drugs in killing parasites, severe malaria still causes up to one million deaths every year. A new strategy targeting both parasite elimination and EC protection is urgently needed in the field. Recently, a rho-kinase inhibitior Fasudil, a drug already in clinical use in humans for cardio- and neuro-vascular diseases, was successfully tested on laboratory strains of P. falciparum to protect and to reverse damages of the endothelium. We therefore assessed herein whether Fasudil would have a similar efficiency on P. falciparum taken directly from malaria patients using contact and non-contact experiments. Seven (23.3%) of 30 PRBC preparations from different patients were apoptogenic, four (13.3%) acting by cytoadherence and three (10%) via soluble factors. None of the apoptogenic PRBC preparations used both mechanisms indicating a possible mutual exclusion of signal transduction ligand. Three PRBC preparations (42.9%) induced EC apoptosis by cytoadherence after 4 h of coculture (“rapid transducers”), and four (57.1%) after a minimum of 24 h (“slow transducers”). The intensity of apoptosis increased with time. Interestingly, Fasudil inhibited EC apoptosis mediated both by cell-cell contact and by soluble factors but did not affect PRBC cytoadherence. Fasudil was found to be able to prevent endothelium apoptosis from all the P. falciparum isolates tested. Our data provide evidence of the strong anti-apoptogenic effect of Fasudil and show that endothelial cell-P. falciparum

  10. Radiosensitization of Human Vascular Endothelial Cells Through Hsp90 Inhibition With 17-N-Allilamino-17-Demethoxygeldanamycin

    SciTech Connect

    Kabakov, Alexander E. Makarova, Yulia M.; Malyutina, Yana V.

    2008-07-01

    Purpose: In addition to invasive tumor cells, endothelial cells (ECs) of the tumor vasculature are an important target for anticancer radiotherapy. The purpose of the present work is to investigate how 17-N-allilamino-17-demethoxygeldanamycin (17AAG), known as an anticancer drug inhibiting heat shock protein 90 (Hsp90), modifies radiation responses of human vascular ECs. Methods and Materials: The ECs cultured from human umbilical veins were exposed to {gamma}-irradiation, whereas some EC samples were pretreated with growth factors and/or 17AAG. Postirradiation cell death/survival and morphogenesis were assessed by means of terminal deoxynucleotidyl transferase biotin-deoxyuridine triphosphate nick end labeling or annexin V staining and clonogenic and tube-formation assays. The 17AAG-affected expression and phosphorylation of radioresistance-related proteins were probed by means of immunoblotting. Dominant negative or constitutively activated Akt was transiently expressed in ECs to manipulate Akt activity. Results: It was found that nanomolar concentrations of 17AAG sensitize ECs to relatively low doses (2-6 Gy) of {gamma}-irradiation and abolish the radioprotective effects of vascular endothelial growth factor and basic fibroblast growth factor. The drug-induced radiosensitization of ECs seems to be caused by prevention of Hsp90-dependent phosphorylation (activation) of Akt that results in blocking the radioprotective phosphatidylinositol 3-kinase/Akt pathway. Conclusions: Clinically achievable concentrations of 17AAG can decrease the radioresistance intrinsic to vascular ECs and minimize the radioprotection conferred upon them by tumor-derived growth factors. These findings characterize 17AAG as a promising radiosensitizer for the tumor vasculature.

  11. HCV Infection Induces Autocrine Interferon Signaling by Human Liver Endothelial Cell and Release of Exosomes, Which Inhibits Viral Replication

    PubMed Central

    Giugliano, Silvia; Kriss, Michael; Golden-Mason, Lucy; Dobrinskikh, Evgenia; Stone, Amy E.L.; Soto-Gutierrez, Alejandro; Mitchell, Angela; Khetani, Salman R.; Yamane, Daisuke; Stoddard, Mark; Li, Hui; Shaw, George M.; Edwards, Michael G.; Lemon, Stanley M.; Gale, Michael; Shah, Vijay H.; Rosen, Hugo R.

    2014-01-01

    Background & Aims Liver sinusoidal endothelial cells (LSECs) make up a large proportion of the non-parenchymal cells in the liver. LSECs are involved in induction of immune tolerance, but little is known about their functions during hepatitis C virus (HCV) infection. Methods Primary human LSECs (HLSECs) and immortalized liver endothelial cells (TMNK-1) were exposed to various forms of HCV, including full-length transmitted/founder virus, sucrose-purified Japanese Fulminant Hepatitis-1 (JFH-1), a virus encoding a luciferase reporter, and the HCV-specific pathogen-associated molecular pattern molecules. Cells were analyzed by confocal immunofluorescence, immunohistochemical, and PCR assays. Results HLSECs internalized HCV, independent of cell–cell contacts; HCV RNA was translated but not replicated. Through pattern recognition receptors (TLR7 and retinoic acid inducible gene 1), HCV RNA induced consistent and broad transcription of multiple interferons (IFNs); supernatants from primary HLSECs transfected with HCV-specific pathogen-associated molecular pattern molecules increased induction of IFNs and IFN-stimulated genes in HLSECs. Recombinant type I and type III IFNs strongly up-regulated HLSEC transcription of interferon λ 3 (IFNL3) and viperin (RSAD2), which inhibit replication of HCV. Compared to CD8+ T cells, HLSECs suppressed HCV replication within Huh7.5.1 cells, also inducing IFN-stimulated genes in co-culture. Conditioned media from IFN-stimulated HLSECs induced expression of antiviral genes by uninfected primary human hepatocytes. Exosomes, derived from HLSECs following stimulation with either type I or type III IFNs, controlled HCV replication in a dose-dependent manner. Conclusions Cultured HLSECs produce factors that mediate immunity against HCV. HLSECs induce self-amplifying IFN-mediated responses and release of exosomes with antiviral activity. PMID:25447848

  12. EETs alleviate ox-LDL-induced inflammation by inhibiting LOX-1 receptor expression in rat pulmonary arterial endothelial cells.

    PubMed

    Jiang, Jun-xia; Zhang, Shui-juan; Liu, Ya-nan; Lin, Xi-xi; Sun, Yan-hong; Shen, Hui-juan; Yan, Xiao-feng; Xie, Qiang-min

    2014-03-15

    Oxidized low-density lipoprotein (Ox-LDL) is associated with atherosclerotic events through the modulation of arachidonic acid (AA) metabolism and activation of inflammatory signaling. Cytochrome P450 (CYP) epoxygenase-derived epoxyeicosatrienoic acids (EETs) mitigate inflammation through nuclear factor-κB (NF-κB). In this study, we explored the effects and mechanisms of exogenous EETs on the ox-LDL-induced inflammation of pulmonary artery endothelial cells (PAECs), which were cultured from rat pulmonary arteries. We determined that pre-treatment with 11,12-EET or 14,15-EET attenuated the ox-LDL-induced expression and release of intercellular adhesion molecule-1 (ICAM-1), E-selectin, and monocyte chemoattractant protein-1 (MCP-1) in a concentration-dependent manner. In addition, the ox-LDL-induced expression of CYP2J4 was upregulated by 11,12-EET and 14,15-EET (1μM). Furthermore, the endothelial receptor of lectin-like oxidized low-density lipoprotein (LOX-1) was downregulated in PAECs treated with EETs. The inflammatory responses evoked by ox-LDL (100μg/mL) were blocked by pharmacological inhibitors of Erk1/2 mitogen-activated protein kinase (MAPK) (U0126), p38 MAPK (SB203580), and NF-κB (PDTC). In addition, we confirmed that 11,12-EET suppresses phosphorylation of p38, degradation of IκBα, and activation of NF-κB (p65), whereas 14,15-EET can significantly suppress the phosphorylation of p38 and Erk1/2. Our results indicate that EETs exert beneficial effects on ox-LDL-induced inflammation primarily through the inhibition of LOX-1 receptor upregulation, MAPK phosphorylation, and NF-κB activation and through the upregulation of CYP2J4 expression. This study helps focus the current understanding of the contribution of EETs to the regulation of the inflammation of pulmonary vascular endothelial cells. Furthermore, the therapeutic potential of targeting the EET pathway in pulmonary vascular disease will be highlighted.

  13. Albendazole inhibits endothelial cell migration, tube formation, vasopermeability, VEGF receptor-2 expression and suppresses retinal neovascularization in ROP model of angiogenesis

    SciTech Connect

    Pourgholami, Mohammad H.; Khachigian, Levon M.; Fahmy, Roger G.; Badar, Samina; Wang, Lisa; Chu, Stephanie Wai Ling; Morris, David Lawson

    2010-07-09

    The angiogenic process begins with the cell proliferation and migration into the primary vascular network, and leads to vascularization of previously avascular tissues and organs as well to growth and remodeling of the initially homogeneous capillary plexus to form a new microcirculation. Additionally, an increase in microvascular permeability is a crucial step in angiogenesis. Vascular endothelial growth factor (VEGF) plays a central role in angiogenesis. We have previously reported that albendazole suppresses VEGF levels and inhibits malignant ascites formation, suggesting a possible effect on angiogenesis. This study was therefore designed to investigate the antiangiogenic effect of albendazole in non-cancerous models of angiogenesis. In vitro, treatment of human umbilical vein endothelial cells (HUVECs) with albendazole led to inhibition of tube formation, migration, permeability and down-regulation of the VEGF type 2 receptor (VEGFR-2). In vivo albendazole profoundly inhibited hyperoxia-induced retinal angiogenesis in mice. These results provide new insights into the antiangiogenic effects of albendazole.

  14. (-)-Epigallocatechin-3-gallate decreases thrombin/paclitaxel-induced endothelial tissue factor expression via the inhibition of c-Jun terminal NH2 kinase phosphorylation

    SciTech Connect

    Wang, Huang-Joe; Lo, Wan-Yu; Lu, Te-Ling; Huang, Haimei

    2010-01-01

    Patients with paclitaxel-eluting stents are concerned with stent thrombosis caused by premature discontinuation of dual antiplatelet therapy or clopidogrel resistance. This study investigates the effect of (-)-epigallocatechin-3-gallate (EGCG) on the expression of thrombin/paclitaxel-induced endothelial tissue factor (TF) expressions in human aortic endothelial cells (HAECs). EGCG was nontoxic to HAECs at 6 h up to a concentration of 25 {mu}mol/L. At a concentration of 25 {mu}mol/L, EGCG pretreatment potently inhibited both thrombin-stimulated and thrombin/paclitaxel-stimulated endothelial TF protein expression. Thrombin and thrombin/paclitaxel-induced 2.6-fold and 2.9-fold increases in TF activity compared with the control. EGCG pretreatment caused a 29% and 38% decrease in TF activity on thrombin and thrombin/paclitaxel treatment, respectively. Real-time polymerase chain reaction (PCR) showed that thrombin and thrombin/paclitaxel-induced 3.0-fold and 4.6-fold TF mRNA expressions compared with the control. EGCG pretreatment caused an 82% and 72% decrease in TF mRNA expression on thrombin and thrombin/paclitaxel treatment, respectively. The c-Jun terminal NH2 kinase (JNK) inhibitor SP600125 reduced thrombin/paclitaxel-induced TF expression. Furthermore, EGCG significantly inhibited the phosphorylation of JNK to 49% of thrombin/paclitaxel-stimulated HAECs at 60 min. Immunofluorescence assay did not show an inhibitory effect of EGCG on P65 NF-{kappa}B nuclear translocation in the thrombin/paclitaxel-stimulated endothelial cells. In conclusion, EGCG can inhibit TF expression in thrombin/paclitaxel-stimulated endothelial cells via the inhibition of JNK phosphorylation. The unique property of EGCG may be used to develop a new drug-eluting stent by co-coating EGCG and paclitaxel.

  15. Inhibition of interleukin-1β-induced endothelial tissue factor expression by the synthetic cannabinoid WIN 55,212-2

    PubMed Central

    Scholl, Antje; Ivanov, Igor; Hinz, Burkhard

    2016-01-01

    The role of cannabinoids in thrombosis remains controversial. In view of the primary importance of tissue factor (TF) in blood coagulation and its involvement in the pathology of several cardiovascular, inflammatory and neoplastic diseases, a regulation of this initial procoagulant signal seems to be of particular interest. Using human umbilical vein endothelial cells (HUVEC) the present study investigated the impact of the synthetic cannabinoid WIN 55,212-2 on interleukin (IL)-1β-induced TF expression and activity. WIN 55,212-2 caused a time- and concentration-dependent suppression of IL-1β-induced TF protein accompanied by decreases in TF mRNA and activity. Inhibition of TF protein expression by WIN 55,212-2 was mimicked by its cannabinoid receptor-inactive enantiomer WIN 55,212-3 but not by structurally unrelated phyto-, endo- and synthetic cannabinoids. In addition, the inhibitory effect of WIN 55,212-2 was not reversed by antagonists to cannabinoid receptors (CB1, CB2) or transient receptor potential vanilloid 1. Mechanistic approaches revealed WIN 55,212-2 to suppress IL-1β-induced TF expression via inhibition of ceramide formation and via decreased phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinases. Further inhibitor experiments demonstrated neutral sphingomyelinase (nSMase) to confer ceramide generation upon IL-1β treatment with the parallel IL-1β-mediated activation of MAPKs occurring via an nSMase-independent pathway. Finally, a receptor-independent inhibition of IL-1β-induced TF protein by WIN 55,212-2 was confirmed in human blood monocytes. Collectively, this data provide a hitherto unknown receptor-independent anticoagulatory action of the cannabinoid WIN 55,212-2. PMID:27556861

  16. Andrographolide, a Novel NF-κB Inhibitor, Inhibits Vascular Smooth Muscle Cell Proliferation and Cerebral Endothelial Cell Inflammation

    PubMed Central

    Chang, Chao-Chien; Duann, Yeh-Fang; Yen, Ting-Lin; Chen, Yu-Ying; Jayakumar, Thanasekaran; Ong, Eng-Thiam; Sheu, Joen-Rong

    2014-01-01

    Background Aberrant vascular smooth muscle cell (VSMC) proliferation and cerebral endothelial cell (CEC) dysfunction contribute significantly in the pathogenesis of cardiovascular diseases. Therefore, inhibition of these cellular events would be by candidate agents for treating these diseases. In the present study, the mechanism of anti-proliferative and anti-inflammatory effects of andrographolides, a novel nuclear factor-κB inhibitor, was investigated in VSMC and CEC cells. Methods VSMCs and CECs were isolated from rat artery and mouse brain, respectively, and cultured before experimentation. The effect of andro on platelet-derived growth factor-BB (PDGF-BB) induced VSMC cell proliferation was evaluated by cell number, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression of extracellular signal regulated kinase 1/2 (ERK1/2), proliferating cell nuclear antigen (PCNA), and the effects on lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) and, cyclooxygenase-2 (COX2) were detected by Western blotting. Results Andro significantly inhibited PDGF-BB (10 ng/ml) induced cell proliferation in a concentration (20-100 μM) dependent manner, which may be due to reducing the expression of ERK1/2, and by inhibiting the expression of PCNA. Andro also remarkably diminished LPS-induced iNOS and COX2 expression. Conclusions The results of this study suggested that the effects of andro against VSMCs proliferation and CECs dysfunction may represent a promising approach for treatment of vascular diseases. PMID:27122804

  17. Inhibition of interleukin-1β-induced endothelial tissue factor expression by the synthetic cannabinoid WIN 55,212-2.

    PubMed

    Scholl, Antje; Ivanov, Igor; Hinz, Burkhard

    2016-09-20

    The role of cannabinoids in thrombosis remains controversial. In view of the primary importance of tissue factor (TF) in blood coagulation and its involvement in the pathology of several cardiovascular, inflammatory and neoplastic diseases, a regulation of this initial procoagulant signal seems to be of particular interest. Using human umbilical vein endothelial cells (HUVEC) the present study investigated the impact of the synthetic cannabinoid WIN 55,212-2 on interleukin (IL)-1β-induced TF expression and activity. WIN 55,212-2 caused a time- and concentration-dependent suppression of IL-1β-induced TF protein accompanied by decreases in TF mRNA and activity. Inhibition of TF protein expression by WIN 55,212-2 was mimicked by its cannabinoid receptor-inactive enantiomer WIN 55,212-3 but not by structurally unrelated phyto-, endo- and synthetic cannabinoids. In addition, the inhibitory effect of WIN 55,212-2 was not reversed by antagonists to cannabinoid receptors (CB1, CB2) or transient receptor potential vanilloid 1. Mechanistic approaches revealed WIN 55,212-2 to suppress IL-1β-induced TF expression via inhibition of ceramide formation and via decreased phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinases. Further inhibitor experiments demonstrated neutral sphingomyelinase (nSMase) to confer ceramide generation upon IL-1β treatment with the parallel IL-1β-mediated activation of MAPKs occurring via an nSMase-independent pathway. Finally, a receptor-independent inhibition of IL-1β-induced TF protein by WIN 55,212-2 was confirmed in human blood monocytes. Collectively, this data provide a hitherto unknown receptor-independent anticoagulatory action of the cannabinoid WIN 55,212-2.

  18. Edaravone protected human brain microvascular endothelial cells from methylglyoxal-induced injury by inhibiting AGEs/RAGE/oxidative stress.

    PubMed

    Li, Wenlu; Xu, Hongjiao; Hu, Yangmin; He, Ping; Ni, Zhenzhen; Xu, Huimin; Zhang, Zhongmiao; Dai, Haibin

    2013-01-01

    Subjects with diabetes experience an increased risk of cerebrovascular disease and stroke compared with nondiabetic age-matched individuals. Increased formation of reactive physiological dicarbonyl compound methylglyoxal (MGO) seems to be implicated in the development of diabetic vascular complication due to its protein glycation and oxidative stress effect. Edaravone, a novel radical scavenger, has been reported to display the advantageous effects on ischemic stroke both in animals and clinical trials; however, little is known about whether edaravone has protective effects on diabetic cerebrovascular injury. Using cultured human brain microvascular endothelial cells (HBMEC), protective effects of edaravone on MGO and MGO enhancing oxygen-glucose deprivation (OGD) induced injury were investigated. Cell injury was measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) formation, cell account, lactate dehydrogenase (LDH) release and Rhodamine 123 staining. Advanced glycation end-products (AGEs) formation and receptor for advanced glycation end-products (RAGE) expression were measured by western blotting. Cellular oxidative stress was measured by reactive oxygen species (ROS) release. Treatment of MGO for 24 h significantly induced HBMEC injury, which was inhibited by pretreatment of edaravone from 10-100 µmol/l. What's more, treatment of MGO enhanced AGEs accumulation, RAGE expression and ROS release in the cultured HBMEC, which were inhibited by 100 µmol/l edaravone. Finally, treatment of MGO for 24 h and then followed by 3 h OGD insult significantly enhanced cell injury when compared with OGD insult only, which was also protected by 100 µmol/l edaravone. Thus, edaravone protected HBMEC from MGO and MGO enhancing OGD-induced injury by inhibiting AGEs/RAGE/oxidative stress.

  19. Losartan Attenuates Myocardial Endothelial-To-Mesenchymal Transition in Spontaneous Hypertensive Rats via Inhibiting TGF-β/Smad Signaling

    PubMed Central

    Wu, Miao; Peng, Zhenyu; Zu, Changhao; Ma, Jing; Lu, Shijuan; Zhong, Jianghua; Zhang, Saidan

    2016-01-01

    Background Losartan plays an important role in the inhibition of myocardial fibrosis. But the underlying mechanism is not entirely clear. Emerging evidences have indicated that endothelial-to-mesenchymal transition (EndMT) plays a crucial role in cardiac fibrosis. Here the present study aims to first investigated the effect of Losartan on EndMT in cardiac fibrosis of spontaneous hypertensive rats (SHRs). Methods Male SHRs were randomly divided into three groups and fed for 12 weeks, namely the SHR group (Group S), the Losartan-treated group (Group L) and the Prazosin-treated group (Group P). Wistar-Kyoto rats served as controls (Group W). The histological changes were evaluated by Masson’s trichrome. Co-expression of CD31 and fibroblast-specific protein 1 (FSP1) were used as the markers of EndMT through immunofluorescence. The expressions of FSP1, CD31, TGF-β, Smad were detected by Western blot analysis. Results It was identified that elevated blood pressure induced a significant increase in myocardial fibrosis and EndMT in SHRs, which was reversed by Losartan and Prazosin treatment. Furthermore, the activity of TGF-β/Smad signaling was detected in the four groups. TGF-β/Smad signaling was activated in SHRs and suppressed by Losartan or Prazosin treatment. Losartan exhibited more efficiently than Prazosin in inhibiting TGF-β/Smad signaling activation, EndMT and myocardial fibrosis. Conclusion These results showed that EndMT played an important role in promoting hypertensive cardiac fibrosis, and that losartan could suppress cardiac fibrosis through the inhibition of EndMT via classical TGF-β/Smad pathway. PMID:27176484

  20. [Slfn1 inhibited the migration of endothelial progenitor cells in vitro].

    PubMed

    Zhang, Lu; Kuang, Chunyan; Yang, Tianhe; Wu, Qiang; Zhang, Yang

    2014-11-01

    To explore the effect of Schlafen 1 (Slfn1) on the migration of endothelial progenitor cells (EPCs). Rat bone marrow derived EPCs were isolated and cultured. Ad-Slfn1, ShRNA-Slfn1, ShRNA-control and Ad-control were transfected into EPCs respectively. The mRNA expression of Slfn1 and Cyclin D1 was examined by reverse transcriptase-PCR, and their protein expression was detected by Western blot. The migration of EPCs was examined by a modified Boyden chamber assay.EPCs cell cycle was determined using flow cytometry analysis. Forty-eight hours after ShRNA-Slfn1 transfection, the mRNA and protein expression of Slfn1 in EPCs was significantly down-regulated compared to ShRNA-control EPCs (P < 0.05). Transfection of Ad-Slfn1 reversed these changes.Overexpression of Slfn1 reduced the migration capacity of EPCs while the silencing of Slfn1 by shRNA-Slfn1 increased the migration capacity of EPCs.In addition, cell cycle was arrested at G1 phase in Slfn1 overexpression group while transfection of shRNA-Slfn1 reversed these responses.Interestingly, the mRNA and protein expression of Cyclin D1 was significantly up-regulated after shRNA-Slfn1 transfection compared to ShRNA-control group (all P < 0.05), but overexpression of Slfn1 reversed these results, suggesting Cyclin D1 was involved in regulating EPCs cell cycle via Slfn1 signaling. Slfn1 could reduce the migration capacity of EPCs via Cyclin D1 pathway.

  1. Red Raspberry Phenols Inhibit Angiogenesis: A Morphological and Subcellular Analysis Upon Human Endothelial Cells.

    PubMed

    Sousa, M; Machado, V; Costa, R; Figueira, M E; Sepodes, B; Barata, P; Ribeiro, L; Soares, R

    2016-07-01

    Polyphenols are a class of natural compounds whose potential as antioxidant, anti-inflammatory, and anti-angiogenesis has been reported in many pathological conditions. Red raspberry extract, rich in polyphenols, has been reported to exert anti-inflammatory effects and prevent cell proliferation in distinct animal models. However, the signaling pathways involved remain unknown. Herein, we used human microvascular endothelial cells (HMVECs) to determine the influence of red raspberry phenolic compound extract concentrations, ranging from 10 to 250 µg gallic acid equivalents (GAE)/mL, on endothelium viability (MTS assay), proliferation (BrdU incorporation), migration (injury assay), and capillary-like structures formation (Matrigel assay). Protein expression in cell lysates was determined by Western blot analysis. We showed that red raspberry extracts reduced cell viability (GI50  = 87,64 ± 6,59 μg GAE/mL) and proliferation in a dose-dependent manner. A significant abrogation of cells ability to migrate to injured areas, even at low concentrations, was observed by injury assay. Cell assembly into capillary-like structures on Matrigel also decreased in a dose dependent-manner for higher extract concentrations, as well as the number of branching points per unit of area. Protein expression analysis showed a dose-dependent decrease in Phospho-VEGFR2 expression, implying abrogation of VEGF signaling activity. We also showed for the first time that red raspberry phenolic compounds induce the rearrangement of filamentous actin cytoskeleton, with an isotropy increase found for higher testing concentrations. Taken together, our findings corroborate the anti-angiogenic potential of red raspberry phenolic compounds and provide new insights into their mode of action upon endothelium. J. Cell. Biochem. 117: 1604-1612, 2016. © 2015 Wiley Periodicals, Inc.

  2. Signatures of anthocyanin metabolites identified in humans inhibit biomarkers of vascular inflammation in human endothelial cells

    PubMed Central

    Warner, Emily F.; Smith, Michael J.; Zhang, Qingzhi; Raheem, K. Saki; O'Hagan, David; O'Connell, Maria A.

    2017-01-01

    Scope The physiological relevance of contemporary cell culture studies is often perplexing, given the use of unmetabolized phytochemicals at supraphysiological concentrations. We investigated the activity of physiologically relevant anthocyanin metabolite signatures, derived from a previous pharmacokinetics study of 500 mg 13C5‐cyanidin‐3‐glucoside in eight healthy participants, on soluble vascular adhesion molecule‐1 (VCAM‐1) and interleukin‐6 (IL‐6) in human endothelial cells. Methods and results Signatures of peak metabolites (previously identified at 1, 6, and 24 h post‐bolus) were reproduced using pure standards and effects were investigated across concentrations ten‐fold lower and higher than observed mean (<5 μM) serum levels. Tumor necrosis factor‐α (TNF‐α)‐stimulated VCAM‐1 was reduced in response to all treatments, with maximal effects observed for the 6 and 24 h profiles. Profiles tested at ten‐fold below mean serum concentrations (0.19–0.44 μM) remained active. IL‐6 was reduced in response to 1, 6, and 24 h profiles, with maximal effects observed for 6 h and 24 h profiles at concentrations above 2 μM. Protein responses were reflected by reductions in VCAM‐1 and IL‐6 mRNA, however there was no effect on phosphorylated NFκB‐p65 expression. Conclusion Signatures of anthocyanin metabolites following dietary consumption reduce VCAM‐1 and IL‐6 production, providing evidence of physiologically relevant biological activity. PMID:28457017

  3. A hot water extract of Curcuma longa inhibits adhesion molecule protein expression and monocyte adhesion to TNF-α-stimulated human endothelial cells.

    PubMed

    Kawasaki, Kengo; Muroyama, Koutarou; Yamamoto, Norio; Murosaki, Shinji

    2015-01-01

    The recruitment of arterial leukocytes to endothelial cells is an important step in the progression of various inflammatory diseases. Therefore, its modulation is thought to be a prospective target for the prevention or treatment of such diseases. Adhesion molecules on endothelial cells are induced by proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), and contribute to the recruitment of leukocytes. In the present study, we investigated the effect of hot water extract of Curcuma longa (WEC) on the protein expression of adhesion molecules, monocyte adhesion induced by TNF-α in human umbilical vascular endothelial cells (HUVECs). Treatment of HUVECs with WEC significantly suppressed both TNF-α-induced protein expression of adhesion molecules and monocyte adhesion. WEC also suppressed phosphorylation and degradation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) induced by TNF-α in HUVECs, suggesting that WEC inhibits the NF-κB signaling pathway.

  4. Resuscitation of traumatic hemorrhagic shock patients with hypertonic saline-without dextran-inhibits neutrophil and endothelial cell activation.

    PubMed

    Junger, Wolfgang G; Rhind, Shawn G; Rizoli, Sandro B; Cuschieri, Joseph; Shiu, Maria Y; Baker, Andrew J; Li, Linglin; Shek, Pang N; Hoyt, David B; Bulger, Eileen M

    2012-10-01

    Posttraumatic inflammation and excessive neutrophil activation cause multiple organ dysfunction syndrome (MODS), a major cause of death among hemorrhagic shock patients. Traditional resuscitation strategies may exacerbate inflammation; thus, novel fluid treatments are needed to reduce such posttraumatic complications. Hypertonic resuscitation fluids inhibit inflammation and reduce MODS in animal models. Here we studied the anti-inflammatory efficacy of hypertonic fluids in a controlled clinical trial. Trauma patients in hypovolemic shock were resuscitated in a prehospital setting with 250 mL of either 7.5% hypertonic saline (HS; n = 9), 7.5% hypertonic saline + 6% dextran 70 (HSD; n = 8), or 0.9% normal saline (NS; n = 17). Blood samples were collected on hospital admission and 12 and 24 h after resuscitation. Multicolor flow cytometry was used to quantify neutrophil expression of cell-surface activation/adhesion (CD11b, CD62L, CD64) and degranulation (CD63, CD66b, CD35) markers as well as oxidative burst activity. Circulating concentrations of soluble intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVACM-1), P- and E-selectins, myeloperoxidase (MPO), and matrix metalloproteinase 9 (MMP-9) were assessed by immunoassay. Multiple organ dysfunction syndrome, leukocytosis, and mortality were lower in the HS and HSD groups than in the NS group. However, these differences were not statistically significant. Hypertonic saline prevented priming and activation and neutrophil oxidative burst and CD11b and CD66b expression. Hypertonic saline also reduced circulating markers of neutrophil degranulation (MPO and MMP-9) and endothelial cell activation (sICAM-1, sVCAM-1, soluble E-selectin, and soluble P-selectin). Hypertonic saline + 6% dextran 70 was less capable than HS of suppressing the upregulation of most of these activation markers. This study demonstrates that initial resuscitation with HS, but neither NS nor HSD, can attenuate

  5. Resuscitation of traumatic hemorrhagic shock patients with hypertonic saline - without dextran - inhibits neutrophil and endothelial cell activation

    PubMed Central

    Junger, Wolfgang G.; Rhind, Shawn G.; Rizoli, Sandro B.; Cuschieri, Joseph; Shiu, Maria Y.; Baker, Andrew J.; Li, Linglin; Shek, Pang N.; Hoyt, David B.; Bulger, Eileen M.

    2012-01-01

    Background Post-traumatic inflammation and excessive neutrophil activation cause multiple organ dysfunction syndrome (MODS), a major cause of death among hemorrhagic shock patients. Traditional resuscitation strategies may exacerbate inflammation and thus novel fluid treatments are needed to reduce these post-traumatic complications. Hypertonic resuscitation fluids inhibit inflammation and reduce MODS in animal models. Here we studied the anti-inflammatory efficacy of hypertonic fluids in a controlled clinical trial. Methods Trauma patients in hypovolemic shock were resuscitated in a pre-hospital setting with 250 ml of either 7.5% hypertonic saline (HS; n=9), 7.5% hypertonic saline + 6% dextran-70 (HSD; n=8), or 0.9% normal saline (NS; n=17). Blood samples were collected on hospital admission and 12 and 24 h post-resuscitation. Multi-color flow cytometry was used to quantify neutrophil expression of cell-surface activation/adhesion (CD11b, CD62L, CD64) and degranulation (CD63, CD66b, CD35) markers as well as oxidative burst activity. Circulating concentrations of soluble intercellular adhesion molecule (sICAM)-1, vascular cell adhesion molecule (sVCAM)-1, P-, E-selectins, myeloperoxidase (MPO), and matrix metallopeptidase (MMP)-9 were assessed with immunoassays. Results MODS, leukocytosis, and mortality were lower in the HS and HSD groups than in the NS group. However, these differences were not statistically significant. HS prevented priming and activation and neutrophil oxidative burst and CD11b and CD66b expression. HS also reduced circulating markers of neutrophil degranulation (MPO and MMP-9) and endothelial cell activation (sICAM-1, cVCAM-1, sE-selectin, and sP-selectin). HSD was less capable than HS of suppressing the upregulation of most of these activation markers. Conclusions This study demonstrates that initial resuscitation with HS but neither NS nor HSD can attenuate post-traumatic neutrophil and endothelial cell activation in hemorrhagic shock

  6. Dual NEP/ECE inhibition improves endothelial function in mesenteric resistance arteries of 32-week-old SHR.

    PubMed

    Lemkens, Pieter; Spijkers, Leon Ja; Meens, Merlijn J; Nelissen, Jelly; Janssen, Ben; Peters, Stephan Lm; Schiffers, Paul Mh; De Mey, Jo Gr

    2017-03-16

    Endothelin 1 (ET-1), a potent vasoconstrictor, pro-mitogenic and pro-inflammatory peptide, may promote development of endothelial dysfunction and arterial remodeling. ET-1 can be formed through cleavage of big-ET-1 by endothelin-converting enzyme (ECE) or neutral endopeptidase (NEP). We investigated whether chronic treatment with the novel dual NEP/ECE inhibitor SOL1 improves functional and structural properties of resistance-sized arteries of 32-week-old male spontaneously hypertensive rats (SHR). SHR received a chronic 4-week treatment with SOL1, losartan or hydralazine. We then compared effects of inhibition of NO synthase (NOS) (100 μM l-NAME), blockade of ETA- and ETB-receptors (10 μM bosentan) and stimulation of the endothelium with 0.001-10 μM acetylcholine (ACh) in isolated third-order mesenteric resistance arteries. Losartan and hydralazine significantly lowered blood pressure. Losartan decreased the media-to-lumen ratio of resistance arteries. l-NAME (1) increased arterial contractile responses to K(+) (5.9-40 mM) in the losartan, SOL1 and vehicle group and (2) increased the sensitivity to phenylephrine (PHE; 0.16-20 μM) in the SOL1 group but not in the losartan, hydralazine and vehicle group. Relaxing responses to ACh in the absence or presence of l-NAME during contractions induced by either 10 μM PHE or 40 mM K(+) were not altered by any in vivo treatment. Acute treatment with bosentan did, however, significantly improve maximal relaxing responses involving endothelium-derived nitric oxide and -hyperpolarizing factors in the SOL1 group but not in the losartan, hydralazine or vehicle group. Thus, chronic inhibition of NEP/ECE improved basal endothelial function but did not alter blood pressure, resistance artery structure and stimulated endothelium-dependent relaxing responses in 32-week-old SHR.Hypertension Research advance online publication, 16 March 2017; doi:10.1038/hr.2017.38.

  7. PJ-34 inhibits PARP-1 expression and ERK phosphorylation in glioma-conditioned brain microvascular endothelial cells.

    PubMed

    Motta, Carla; D'Angeli, Floriana; Scalia, Marina; Satriano, Cristina; Barbagallo, Davide; Naletova, Irina; Anfuso, Carmelina Daniela; Lupo, Gabriella; Spina-Purrello, Vittoria

    2015-08-15

    Inhibitors of PARP-1(Poly(ADP-ribose) polymerase-1) act by competing with NAD(+), the enzyme physiological substrate, which play a protective role in many pathological conditions characterized by PARP-1 overactivation. It has been shown that PARP-1 also promotes tumor growth and progression through its DNA repair activity. Since angiogenesis is an essential requirement for these activities, we sought to determine whether PARP inhibition might affect rat brain microvascular endothelial cells (GP8.3) migration, stimulated by C6-glioma conditioned medium (CM). Through wound-healing experiments and MTT analysis, we demonstrated that PARP-1 inhibitor PJ-34 [N-(6-Oxo-5,6-dihydrophenanthridin-2-yl)-N,N-dimethylacetamide] abolishes the migratory response of GP8.3 cells and reduces their viability. PARP-1 also acts in a DNA independent way within the Extracellular-Regulated-Kinase (ERK) signaling cascade, which regulates cell proliferation and differentiation. By western analysis and confocal laser scanning microscopy (LSM), we analyzed the effects of PJ-34 on PARP-1 expression, phospho-ERK and phospho-Elk-1 activation. The effect of MEK (mitogen-activated-protein-kinase-kinase) inhibitor PD98059 (2-(2-Amino-3-methoxyphenyl)-4 H-1-benzopyran-4-one) on PARP-1 expression in unstimulated and in CM-stimulated GP8.3 cells was analyzed by RT-PCR. PARP-1 expression and phospho-ERK activation were significantly reduced by treatment of GP8.3 cells with PJ-34 or PD98059. By LSM, we further demonstrated that PARP-1 and phospho-ERK are coexpressed and share the same subcellular localization in GP8.3 cells, in the cytoplasm as well as in nucleoplasm. Based on these data, we propose that PARP-1 and phospho-ERK interact in the cytosol and then translocate to the nucleus, where they trigger a proliferative response. We also propose that PARP-1 inhibition blocks CM-induced endothelial migration by interfering with ERK signal-transduction pathway.

  8. MicroRNA-210 Modulates Endothelial Cell Response to Hypoxia and Inhibits the Receptor Tyrosine Kinase Ligand Ephrin-A3*S⃞

    PubMed Central

    Fasanaro, Pasquale; D'Alessandra, Yuri; Di Stefano, Valeria; Melchionna, Roberta; Romani, Sveva; Pompilio, Giulio; Capogrossi, Maurizio C.; Martelli, Fabio

    2008-01-01

    MicroRNAs (miRNAs) are small non-protein-coding RNAs that function as negative gene expression regulators. In the present study, we investigated miRNAs role in endothelial cell response to hypoxia. We found that the expression of miR-210 progressively increased upon exposure to hypoxia. miR-210 overexpression in normoxic endothelial cells stimulated the formation of capillary-like structures on Matrigel and vascular endothelial growth factor-driven cell migration. Conversely, miR-210 blockade via anti-miRNA transfection inhibited the formation of capillary-like structures stimulated by hypoxia and decreased cell migration in response to vascular endothelial growth factor. miR-210 overexpression did not affect endothelial cell growth in both normoxia and hypoxia. However, anti-miR-210 transfection inhibited cell growth and induced apoptosis, in both normoxia and hypoxia. We determined that one relevant target of miR-210 in hypoxia was Ephrin-A3 since miR-210 was necessary and sufficient to down-modulate its expression. Moreover, luciferase reporter assays showed that Ephrin-A3 was a direct target of miR-210. Ephrin-A3 modulation by miR-210 had significant functional consequences; indeed, the expression of an Ephrin-A3 allele that is not targeted by miR-210 prevented miR-210-mediated stimulation of both tubulogenesis and chemotaxis. We conclude that miR-210 up-regulation is a crucial element of endothelial cell response to hypoxia, affecting cell survival, migration, and differentiation. PMID:18417479

  9. Cyclopeptide RA-V inhibits angiogenesis by down-regulating ERK1/2 phosphorylation in HUVEC and HMEC-1 endothelial cells

    PubMed Central

    Yue, Grace GL; Fan, Jun-Ting; Lee, Julia KM; Zeng, Guang-Zhi; Ho, Tina WF; Fung, Kwok-Pui; Leung, Ping-Chung; Tan, Ning-Hua; Lau, Clara BS

    2011-01-01

    BACKGROUND AND PURPOSE Anti-angiogenic agents have recently become one of the major adjuvants for cancer therapy. A cyclopeptide, RA-V, has been shown to have anti-tumour activities. Its in vitro anti-angiogenic activities were evaluated in the present study, and the underlying mechanisms were also assessed. EXPERIMENTAL APPROACH Two endothelial cell lines, human umbilical vein endothelial cells (HUVEC) and human microvascular endothelial cells (HMEC-1), were used. The effects of RA-V on the proliferation, cell cycle phase distribution, migration, tube formation and adhesion were assessed. Western blots and real-time PCR were employed to examine the protein and mRNA expression of relevant molecules. KEY RESULTS RA-V inhibited HUVEC and HMEC-1 proliferation dose-dependently with IC50 values of 1.42 and 4.0 nM respectively. RA-V inhibited migration and tube formation of endothelial cells as well as adhesion to extracellular matrix proteins. RA-V treatment down-regulated the protein and mRNA expression of matrix metalloproteinase-2. Regarding intracellular signal transduction, RA-V interfered with the activation of ERK1/2 in both cell lines. Furthermore, RA-V significantly decreased the phosphorylation of JNK in HUVEC whereas, in HMEC-1, p38 MAPK was decreased. CONCLUSIONS AND IMPLICATIONS RA-V exhibited anti-angiogenic activities in HUVEC and HMEC-1 cell lines with changes in function of these endothelial cells. The underlying mechanisms of action involved the ERK1/2 signalling pathway. However, RA-V may regulate different signalling pathways in different endothelial cells. These findings suggest that RA-V has the potential to be further developed as an anti-angiogenic agent. PMID:21518338

  10. Inhibition of the proliferation and acceleration of migration of vascular endothelial cells by increased cysteine-rich motor neuron 1

    SciTech Connect

    Nakashima, Yukiko; Morimoto, Mayuka; Toda, Ken-ichi; Shinya, Tomohiro; Sato, Keizo; Takahashi, Satoru

    2015-07-03

    Cysteine-rich motor neuron 1 (CRIM1) is upregulated only in extracellular matrix gels by angiogenic factors such as vascular endothelial growth factor (VEGF). It then plays a critical role in the tube formation of endothelial cells. In the present study, we investigated the effects of increased CRIM1 on other endothelial functions such as proliferation and migration. Knock down of CRIM1 had no effect on VEGF-induced proliferation or migration of human umbilical vein endothelial cells (HUVECs), indicating that basal CRIM1 is not involved in the proliferation or migration of endothelial cells. Stable CRIM1-overexpressing endothelial F-2 cells, termed CR1 and CR2, were constructed, because it was difficult to prepare monolayer HUVECs that expressed high levels of CRIM1. Proliferation was reduced and migration was accelerated in both CR1 and CR2 cells, compared with normal F-2 cells. Furthermore, the transient overexpression of CRIM1 resulted in decreased proliferation and increased migration of bovine aortic endothelial cells. In contrast, neither proliferation nor migration of COS-7 cells were changed by the overexpression of CRIM1. These results demonstrate that increased CRIM1 reduces the proliferation and accelerates the migration of endothelial cells. These CRIM1 effects might contribute to tube formation of endothelial cells. CRIM1 induced by angiogenic factors may serve as a regulator in endothelial cells to switch from proliferating cells to morphological differentiation. - Highlights: • CRIM1 was upregulated only in tubular endothelial cells, but not in monolayers. • Increased CRIM1 reduced the proliferation of endothelial cells. • Increased CRIM1 accelerated the migration of endothelial cells. • Increased CRIM1 had no effect on the proliferation or migration of COS-7 cells.

  11. Chemical Structures of 4-Oxo-Flavonoids in Relation to Inhibition of Oxidized Low-Density Lipoprotein (LDL)-Induced Vascular Endothelial Dysfunction

    PubMed Central

    Yi, Long; Jin, Xin; Chen, Chun-Ye; Fu, Yu-Jie; Zhang, Ting; Chang, Hui; Zhou, Yong; Zhu, Jun-Dong; Zhang, Qian-Yong; Mi, Man-Tian

    2011-01-01

    Vascular endothelial dysfunction induced by oxidative stress has been demonstrated to be the initiation step of atherosclerosis (AS), and flavonoids may play an important role in AS prevention and therapy. Twenty-three flavonoids categorized into flavones, flavonols, isoflavones, and flavanones, all with 4-oxo-pyronenucleus, were examined for what structural characteristics are required for the inhibitory effects on endothelial dysfunction induced by oxidized low-density lipoprotein (oxLDL). Human vascular endothelial cells EA.hy926 were pretreated with different 4-oxo-flavonoids for 2 hs, and then exposed to oxLDL for another 24 hs. Cell viability and the level of malondialdehyde (MDA), nitric oxide (NO) and soluble intercellular adhesion molecule-1 (sICAM-1) were measured, respectively. Then, correlation analysis and paired comparison were used to analyze the structure–activity relationships. Significant correlations were observed between the number of −OH moieties in total or in B-ring and the inhibitory effectson endothelial dysfunction. Furthermore, 3′,4′-ortho-dihydroxyl on B-ring, 3-hydroxyl on C-ring and 2,3-double bondwere correlated closely to the inhibitory effects of flavonolson cell viability decrease and lipid peroxidation. 5,7-meta-dihydroxyl group on A-ring was crucial for the anti-inflammatory effects of flavones and isoflavones in endothelial cells. Moreover, the substituted position of B-ring on C3 rather than C2 was important for NO release. Additionally, hydroxylation at C6 position significantly attenuated the inhibitory effects of 4-oxo-flavonoids on endothelial dysfunction. Our findings indicated that the effective agents in inhibiting endothelial dysfunction include myricetin, quercetin, luteolin, apigenin, genistein and daidzein. Our work might provide some evidence for AS prevention and a strategy for the design of novel AS preventive agents. PMID:22016603

  12. Chemical structures of 4-oxo-flavonoids in relation to inhibition of oxidized low-density lipoprotein (LDL)-induced vascular endothelial dysfunction.

    PubMed

    Yi, Long; Jin, Xin; Chen, Chun-Ye; Fu, Yu-Jie; Zhang, Ting; Chang, Hui; Zhou, Yong; Zhu, Jun-Dong; Zhang, Qian-Yong; Mi, Man-Tian

    2011-01-01

    Vascular endothelial dysfunction induced by oxidative stress has been demonstrated to be the initiation step of atherosclerosis (AS), and flavonoids may play an important role in AS prevention and therapy. Twenty-three flavonoids categorized into flavones, flavonols, isoflavones, and flavanones, all with 4-oxo-pyronenucleus, were examined for what structural characteristics are required for the inhibitory effects on endothelial dysfunction induced by oxidized low-density lipoprotein (oxLDL). Human vascular endothelial cells EA.hy926 were pretreated with different 4-oxo-flavonoids for 2 hs, and then exposed to oxLDL for another 24 hs. Cell viability and the level of malondialdehyde (MDA), nitric oxide (NO) and soluble intercellular adhesion molecule-1 (sICAM-1) were measured, respectively. Then, correlation analysis and paired comparison were used to analyze the structure-activity relationships. Significant correlations were observed between the number of -OH moieties in total or in B-ring and the inhibitory effectson endothelial dysfunction. Furthermore, 3',4'-ortho-dihydroxyl on B-ring, 3-hydroxyl on C-ring and 2,3-double bondwere correlated closely to the inhibitory effects of flavonolson cell viability decrease and lipid peroxidation. 5,7-meta-dihydroxyl group on A-ring was crucial for the anti-inflammatory effects of flavones and isoflavones in endothelial cells. Moreover, the substituted position of B-ring on C3 rather than C2 was important for NO release. Additionally, hydroxylation at C6 position significantly attenuated the inhibitory effects of 4-oxo-flavonoids on endothelial dysfunction. Our findings indicated that the effective agents in inhibiting endothelial dysfunction include myricetin, quercetin, luteolin, apigenin, genistein and daidzein. Our work might provide some evidence for AS prevention and a strategy for the design of novel AS preventive agents.

  13. Therapeutic concentrations of digitoxin inhibit endothelial focal adhesion kinase and angiogenesis induced by different growth factors.

    PubMed

    Trenti, Annalisa; Zulato, Elisabetta; Pasqualini, Lorenza; Indraccolo, Stefano; Bolego, Chiara; Trevisi, Lucia

    2017-09-01

    Cardiac glycosides are Na(+) /K(+) -ATPases inhibitors used to treat congestive heart failure and cardiac arrhythmias. Epidemiological studies indicate that patients on digitalis therapy are more protected from cancer. Evidence of a selective cytotoxicity against cancer cells has suggested their potential use as anticancer drugs. The effect on angiogenesis of clinically used cardiac glycosides has not been extensively explored. We studied the effect of digoxin, digitoxin and ouabain on early events of the angiogenic process in HUVECs. We determined HUVEC viability, proliferation, migration and differentiation into capillary tube-like structures. We also tested drug activity using an in vivo angiogenesis model. Activation of protein tyrosine kinase 2 (FAK) and signalling proteins associated with the Na(+) /K(+) -ATPase signalosome was determined by Western blotting. Digitoxin and ouabain (1-100 nM) inhibited HUVEC migration, concentration-dependently, without affecting cell viability, while digoxin induced apoptosis at the same concentrations. Digitoxin antagonized growth factor-induced migration and tubularization at concentrations (1-25 nM) within its plasma therapeutic range. The anti-angiogenic effect of digitoxin was confirmed also by in vivo studies. Digitoxin induced Src, Akt and ERK1/2 phosphorylation but did not affect FAK autophosphorylation at Tyr(397) . However, it significantly inhibited growth factor-induced FAK phosphorylation at Tyr(576/577) . Therapeutic concentrations of digitoxin inhibited angiogenesis and FAK activation by several pro-angiogenic stimuli. These novel findings suggest a potential repositioning of digitoxin as a broad-spectrum anti-angiogenic drug for diseases where pathological angiogenesis is involved. © 2017 The British Pharmacological Society.

  14. YC-1 [3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole] inhibits endothelial cell functions induced by angiogenic factors in vitro and angiogenesis in vivo models.

    PubMed

    Pan, Shiow-Lin; Guh, Jih-Hwa; Peng, Chieh-Yu; Wang, Shih-Wei; Chang, Ya-Ling; Cheng, Fong-Chi; Chang, Jau-Hsiang; Kuo, Sheng-Chu; Lee, Fang-Yu; Teng, Che-Ming

    2005-07-01

    Angiogenesis is a process that involves endothelial cell proliferation, migration, invasion, and tube formation, and inhibition of these processes has implications for angiogenesis-mediated disorders. The purpose of this study was to evaluate the antiangiogenic efficacy of YC-1 [3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole] in well characterized in vitro and in vivo systems. YC-1 inhibited the ability of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in a dose-dependent manner to induce proliferation, migration, and tube formation in human umbilical vascular endothelial cells; these outcomes were evaluated using [3H]thymidine incorporation, transwell chamber, and Matrigel-coated slide assays, respectively. YC-1 inhibited VEGF- and bFGF-induced p42/p44 mitogen-activated protein kinase and Akt phosphorylation as well as protein kinase C alpha translocation using Western blot analysis. The effect of YC-1 on angiogenesis in vivo was evaluated using the mouse Matrigel implant model. YC-1 administered orally in doses of 1 to 100 mg/kg/day inhibited VEGF- and bFGF-induced neovascularization in a dose-dependent manner over 7 days. These results indicate that YC-1 has antiangiogenic activity at very low doses. Moreover, in transplantable murine tumor models, YC-1 administered orally displayed a high degree of antitumor activity (treatment-to-control life span ratio > 175%) without cytotoxicity. YC-1 may be useful for treating angiogenesis-dependent human diseases such as cancer.

  15. Minodronate, a nitrogen-containing bisphosphonate, inhibits advanced glycation end product-induced vascular cell adhesion molecule-1 expression in endothelial cells by suppressing reactive oxygen species generation.

    PubMed

    Yamagishi, S; Matsui, T; Nakamura, K; Takeuchi, M

    2005-01-01

    Advanced glycation end products (AGEs), the senescent macroprotein derivatives that form in increased amounts in diabetes, have been implicated in the pathogenesis of diabetic vascular complications. Indeed, AGEs elicit oxidative stress generation in vascular wall cells through an interaction with their receptor (RAGE), thus playing an important role in vascular inflammation and altered gene expression of growth factors and cytokines. We have previously shown that minodronate, a nitrogen-containing bisphosphonate, blocked the angiogenic signaling of vascular endothelial growth factor in ECs through its antioxidative properties. However, the effects of minodronate on AGE-exposed ECs remain to be elucidated. In this study, we investigated whether and how minodronate could inhibit AGE-induced reactive oxygen species (ROS) generation and subsequent vascular cell adhesion molecule-1 (VCAM-1) gene expression in human umbilical vein endothelial cells (HUVEC). Minodronate or an NADPH oxidase inhibitor, diphenylene iodonium, completely inhibited the AGE-induced ROS generation in HUVEC. Geranylgeranyl pyrophosphate reversed the antioxidative properties of minodronate in AGE-exposed ECs. Furthermore, minodronate was found to prevent AGE-induced nuclear factor--KB activation and subsequently suppress VCAM-1 gene expression in HUVEC. These results demonstrate that minodronate could inhibit VCAM- 1 expression in AGE-exposed ECs by suppressing NADPH oxidase-derived ROS generation, probably via inhibition of geranylgeranylation of Rac, a component of endothelial NADPH oxidase. Our present study suggests that minodronate may have a therapeutic potential in the treatment of patients with diabetic vascular complications.

  16. Omega-3 fatty acids inhibit the up-regulation of endothelial chemokines in maintenance hemodialysis patients.

    PubMed

    Hung, Adriana M; Booker, Cindy; Ellis, Charles D; Siew, Edward D; Graves, Amy J; Shintani, Ayumi; Abumrad, Naji N; Himmelfarb, Jonathan; Ikizler, Talat Alp

    2015-02-01

    Chronic systemic inflammation is common in patients with chronic kidney disease on dialysis (CKD5D) and has been considered a key mediator of the increased cardiovascular risk in this patient population. In this study, we tested the hypothesis that supplementation of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) will attenuate the systemic inflammatory process in CKD5D patients. The design was a randomized, double-blinded, placebo controlled pilot trial (NCT00655525). Thirty-eight patients were randomly assigned in a 1 : 1 fashion to receive 2.9 g of eicosapentaenoic acid (C20:5, n-3) plus docosahexaenoic acid (C22:6, n-3) versus placebo for 12 weeks. The primary outcome was change in pro-inflammatory chemokines measured by lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). Secondary outcomes were changes in systemic inflammatory markers. Analysis of covariance was used to compare percent change from baseline to 12 weeks. Thirty-one patients completed 12 weeks and three patients completed 6 weeks of the study. Median age was 52 (interquartile range 45, 60) years, 74% were African-American and 79% were male. Supplementation of ω-3 PUFAs effectively decreased the LPS-induced PBMC expression of RANTES (Regulated upon Activation, Normal T cell Expressed and Secreted) and MCP-1 (Monocyte Chemotactic Protein-1; unadjusted P = 0.04 and 0.06; adjusted for demographics P = 0.02 and 0.05, respectively). There was no significant effect of the intervention on serum inflammatory markers (C-reactive protein, interleukin-6 and procalcitonin). The results of this pilot study suggest that supplementation of ω-3 PUFAs is beneficial in decreasing the levels of endothelial chemokines, RANTES and MCP-1. Studies of larger sample size and longer duration are required to further evaluate effects of ω-3 PUFAs on systemic markers of inflammation, other metabolic parameters and clinical outcomes, particularly cardiovascular outcomes in CKD5D patients.

  17. Telmisartan inhibits the proinflammatory effects of homocysteine on human endothelial cells through activation of the peroxisome proliferator-activated receptor-δ pathway.

    PubMed

    Xu, Shanghua; Song, Huanhuan; Huang, Maozhi; Wang, Kefeng; Xu, Changsheng; Xie, Liangdi

    2014-09-01

    The aim of this study was to investigate the inhibition capacity of telmisartan to endothelial inflammation induced by homocysteine (Hcy) and discuss the proposed mechanism in vitro. Human umbilical vein endothelial cells (HUVECs) were prepared by collagenase digestion and cultured in vitro. An increase in monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) as markers of Hcy-induced endothelial inflammation. HL-60 cell adhesion to HUVECs was measured by rose bengal staining. Nuclear, cytosolic and total nuclear transcription factor-κB (NF-κB) p65 levels were analyzed by western blotting. Peroxisome proliferator-activated receptor-δ (PPARδ) expression by HUVECs exposed to Hcy with or without telmisartan pretreatment was analyzed by RT-PCR and western blotting. Hcy significantly increased the levels of MCP-1 mRNA, VCAM-1 mRNA and monocyte binding to HUVECs. These effects were significantly attenuated by pretreatment with telmisartan and PPARδ agonists. The effect of telmisartan was inhibited by PPARδ antagonists. The Hcy-mediated downregulation of PPARδ mRNA and protein of HUVECs was inhibited by telmisartan. Hcy-mediated upregulation of NF-κB p65 protein levels in nuclear extracts was inhibited by telmisartan and PPARδ agonists. In conclusion, telmisartan exerts potent anti-inflammatory effects in endothelial cells, probably via a binary mechanism involving PPARδ activation and inhibition of the nuclear translocation of NF-κB.

  18. Azilsartan, an angiotensin II type 1 receptor blocker, attenuates tert-butyl hydroperoxide-induced endothelial cell injury through inhibition of mitochondrial dysfunction and anti-inflammatory activity.

    PubMed

    Liu, Hao; Mao, Ping; Wang, Jia; Wang, Tuo; Xie, Chang-Hou

    2016-03-01

    Angiotensin II type 1 receptor (AT1-R) blockers protect against brain ischemia by mechanisms dependent on and independent of arterial blood pressure. However, the effects of AT1-R blockers on brain endothelial cell injury and detailed mechanisms remain unclear. The goal of this study is to investigate whether azilsartan, an AT1-R blocker, could attenuate oxidative injury in endothelial cells via regulating mitochondrial function and inflammatory responses. We found that treatment with azilsartan suppressed tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in murine brain endothelial cells (mBECs) by increasing cell viability, decreasing lactate dehydrogenase (LDH) release and inhibiting cell apoptosis. Azilsartan significantly inhibited reactive oxygen species (ROS) generation and lipid peroxidation, but had no effect on antioxidant system. We also detected preserved mitochondrial function after azilsartan treatment, as evidenced by increased mitochondrial membrane potential (MMP), reduced cytochrome c release, preserved ATP synthesis and inhibited mitochondrial swelling. In addition, azilsartan differently regulated expression of inflammatory cytokines and increased the activation of endothelial nitric oxide synthase (eNOS). Pretreatment with eNOS inhibitor L-NIO partially prevented the azilsartan-induced regulation of cytokines and protection. Furthermore, azilsartan-induced protection in our in vitro model was shown to be associated with protein stability of peroxisome proliferator-activated receptor-γ (PPAR-γ). Overall, our data suggest that the AT1-R blocker azilsartan may have therapeutic values in treating endothelial dysfunction associated neurological disorders through anti-oxidative and anti-inflammatory properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Resveratrol inhibits inflammation and ameliorates insulin resistant endothelial dysfunction via regulation of AMP-activated protein kinase and sirtuin 1 activities.

    PubMed

    Liu, Zifeng; Jiang, Cuihua; Zhang, Jinghua; Liu, Baolin; Du, Qun

    2016-05-01

    Resveratrol is a phytoalexin with beneficial effects on human health. The aim of the present study was to investigate the effects of resveratrol on endothelial dysfunction involved in insulin signaling and inflammation. Endothelial cells were stimulated with palmitate (PA) to induce insulin resistance characterized by a loss of insulin-mediated nitric oxide (NO) production. Diabetes was induced in rats by fructose feeding. The effects of resveratrol and the mechanisms involved were investigated using an aortic relaxation assay and Western blot analysis. In endothelial cells, 0.1-10 μmol/L resveratrol suppressed IκB kinase β (IKKβ)/nuclear factor-κB phosphorylation, as well as tumor necrosis factor-α and interleukin-6 production, and restored the insulin receptor substrate-1 (Irs-1)/Akt/endothelial NO synthase signaling pathway. Furthermore, resveratrol effectively inhibited the mitogenic actions of insulin by decreasing the secretion of endothelin-1 and plasminogen activator inhibitor-1. It also positively regulated AMP-activated kinase (AMPK) and sirtuin 1 (SIRT1) activation, which contributed to the inhibition of inflammation implicated in endothelial insulin resistance. Stimulation with PA and long term-fructose feeding impaired insulin-mediated vessel dilation in rat aorta, whereas pretreatment of aortic rings with resveratrol (0.1-10 μmol/L) or treatment of rats with 5 or 20 mg/kg resveratrol counteracted these changes. The results indicate that resveratrol inhibits inflammation and facilitates insulin phosphatidylinositol 3-kinase signaling by beneficial modulation of IRS-1 function partly via regulation of AMPK and SIRT1 activity in the endothelium. © 2015 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley Sons & Australia, Ltd.

  20. Inhibition of THP-1 cell adhesion to endothelial cells by alpha-tocopherol and alpha-tocotrienol is dependent on intracellular concentration of the antioxidants.

    PubMed

    Noguchi, Noriko; Hanyu, Ryuhei; Nonaka, Aya; Okimoto, Yuko; Kodama, Tatsuhiko

    2003-06-15

    Vitamin E analogs such as alpha-tocopherol and alpha-tocotrienol have been shown to reduce endothelial expression of adhesion molecules. The reactivity of alpha-tocopherol and alpha-tocotrienol in inhibiting lipid peroxidation in vitro was essentially identical but the inhibition of adhesion of THP-1 cells, a monocytic-"like" cell line, to endothelial cells differs substantially. To determine the mechanism underlying this response, human umbilical vein endothelial cells (HUVECs) were assessed for their ability to accumulate vitamin E analogs. alpha-Tocotrienol accumulated in HUVECs to levels approximately 10-fold greater than that of alpha-tocopherol. The decrease in expression of vascular cell adhesion molecule-1 (VCAM-1) and the adhesion of THP-1 cells to HUVECs by alpha-tocopherol and alpha-tocotrienol was also determined. Both alpha-tocopherol and alpha-tocotrienol suppressed VCAM-1 expression and adhesion of THP-1 cells to HUVECs in a concentration-dependent manner. The efficacy of tocotrienol for reduction of VCAM-1 expression and adhesion of THP-1 cells to HUVECs was also 10-fold higher than that of tocopherol. The inhibitory effects of vitamin E analogs on the adhesiveness of endothelial cells clearly correlated with their intracellular concentrations. The data demonstrated that, in assessing the biological responses of antioxidants, intracellular accumulation and metabolism were additional important factors that must be considered.

  1. MicroRNA Mediation of Endothelial Inflammatory Response to Smooth Muscle Cells and its Inhibition by Atheroprotective Shear Stress

    PubMed Central

    Chen, Li-Jing; Chuang, Li; Huang, Yi-Hsuan; Zhou, Jing; Lim, Seh Hong; Lee, Chih-I; Lin, Wei-Wen; Lin, Ting-Er; Wang, Wei-Li; Chen, Linyi; Chien, Shu; Chiu, Jeng-Jiann

    2015-01-01

    Rationale In atherosclerotic lesions, synthetic smooth muscle cells (sSMCs) induce aberrant microRNA (miR) profiles in endothelial cells (ECs) under flow stagnation. Increase in shear stress induces favorable miR modulation to mitigate sSMC-induced inflammation. Objective To address the role of miRs in sSMC-induced EC inflammation and its inhibition by shear stress. Methods and Results Co-culturing ECs with sSMCs under static condition causes initial increases of four anti-inflammatory miRs (146a/708/451/98) in ECs followed by decreases below basal levels at 7 days; the increases for miR-146a/708 peaked at 24 h and those for miR-451/98 lasted for only 6-12 h. Shear stress (12 dynes/cm2) to co-cultured ECs for 24 h augments these four miR expressions. In vivo, these four miRs are highly expressed in neointimal ECs in injured arteries under physiological levels of flow, but not expressed under flow stagnation. MiR-146a, -708, -451, and -98 target interleukin (IL)-1 receptor-associated kinase, inhibitor of nuclear factor-κB (NF-κB) kinase subunit-γ, IL-6 receptor, and conserved helix-loop-helix ubiquitous kinase, respectively, to inhibit NF-κB signaling, which exerts negative feedback control on the biogenesis of these miRs. NF-E2-related factor-2 (Nrf-2) is critical for shear-induction of miR-146a in co-cultured ECs. Silencing either Nrf-2 or miR-146a led to increased neointima formation of injured rat carotid artery under physiological levels of flow. Overexpressing miR-146a inhibits neointima formation of rat or mouse carotid artery induced by injury or flow cessation. Conclusions Nrf-2-mediated miR-146a expression is augmented by atheroprotective shear stress in ECs adjacent to sSMCs to inhibit neointima formation of injured arteries. PMID:25623956

  2. Vesicle miR-195 derived from Endothelial Cells Inhibits Expression of Serotonin Transporter in Vessel Smooth Muscle Cells.

    PubMed

    Gu, Junzhong; Zhang, Huiyuan; Ji, Bingyang; Jiang, Hui; Zhao, Tao; Jiang, Rongcai; Zhang, Zhiren; Tan, Shengjiang; Ahmed, Asif; Gu, Yuchun

    2017-03-08

    Serotonin or 5-hydroxytryptamine (5-HT) has been shown to be essential in lots of physiological and pathological processes. It is well known that 5-HT and 5-HT transporter (5-HTT) play important roles in the pulmonary artery in pulmonary hypertension. However, little is known about the function of 5-HTT in other arteries. In this study we found that the expression of 5-HTT was elevated in injured carotid arteries and over-expression of 5-HTT induced proliferation of smooth muscle cells (SMCs); however, this phenotype could be reversed by knocking-down of 5-HTT or endothelial cells conditional medium (EC-CM). A 5-HTT inhibitor, fluoxetine, treated animals also exhibited reduced restenosis after injury. We identified that miR-195 was packaged in the extracellular vesicles from EC-CM. We further confirmed that extracellular vesicles could transfer miR-195 from ECs to SMCs to inhibit the expression of 5-HTT in SMCs and the proliferation of SMCs. These results provide the first evidence that ECs communicate with SMCs via micro-RNA195 in the regulation of the proliferation of SMCs through 5-HTT, which will contribute to a better understanding of communications between ECs and SMCs via micro-RNA. Our findings suggest a potential target for the control of vessel restenosis.

  3. Antioxidative treatment inhibits the release of thrombogenic tissue factor from irradiation- and cytokine-induced endothelial cells.

    PubMed

    Szotowski, Björn; Antoniak, Silvio; Goldin-Lang, Petra; Tran, Quoc-Viet; Pels, Klaus; Rosenthal, Peter; Bogdanov, Vladimir Y; Borchert, Hans-Hubert; Schultheiss, Heinz-Peter; Rauch, Ursula

    2007-03-01

    The aim of this study was to investigate the effect of the antioxidants pyrrolidine dithiocarbamate (PDTC) and N-acetylcysteine (NAC) on the ionizing radiation (IR)- and tumor necrosis factor-alpha (TNF-alpha) induced tissue factor (TF) expression and its release from human umbilical vein endothelial cells (HUVECs). HUVECs were irradiated with a single dose of either 5 Gy or 10 Gy and stimulated with TNF-alpha (10 ng/mL) in the presence or absence of PDTC and NAC, respectively. Quantitative real-time PCR, ELISA, and TF activity measurements were performed, including TF activity in the supernatant. Apoptosis was detected by flow cytometric active caspase-3 measurement and formation of reactive oxygen species (ROS) by chemiluminescence. We demonstrated a thus far uninvestigated persistent induction of TF expression in HUVECs after treatment with IR and TNF-alpha. Combined stimulation with IR and TNF-alpha led to an immense shedding of microparticle-associated TF which was positively correlated with apoptosis and ROS formation. Antioxidative pre-treatment reduced not only apoptosis and ROS formation, but also the release of thrombogenic microparticles. Antioxidative treatment inhibited apoptosis and shedding of microparticles, thereby reducing thrombogenicity. Thus, antioxidants may help to prevent late thrombosis after antiproliferative treatment when used in combination with anticoagulants.

  4. Vesicle miR-195 derived from Endothelial Cells Inhibits Expression of Serotonin Transporter in Vessel Smooth Muscle Cells

    PubMed Central

    Gu, Junzhong; Zhang, Huiyuan; Ji, Bingyang; Jiang, Hui; Zhao, Tao; Jiang, Rongcai; Zhang, Zhiren; Tan, Shengjiang; Ahmed, Asif; Gu, Yuchun

    2017-01-01

    Serotonin or 5-hydroxytryptamine (5-HT) has been shown to be essential in lots of physiological and pathological processes. It is well known that 5-HT and 5-HT transporter (5-HTT) play important roles in the pulmonary artery in pulmonary hypertension. However, little is known about the function of 5-HTT in other arteries. In this study we found that the expression of 5-HTT was elevated in injured carotid arteries and over-expression of 5-HTT induced proliferation of smooth muscle cells (SMCs); however, this phenotype could be reversed by knocking-down of 5-HTT or endothelial cells conditional medium (EC-CM). A 5-HTT inhibitor, fluoxetine, treated animals also exhibited reduced restenosis after injury. We identified that miR-195 was packaged in the extracellular vesicles from EC-CM. We further confirmed that extracellular vesicles could transfer miR-195 from ECs to SMCs to inhibit the expression of 5-HTT in SMCs and the proliferation of SMCs. These results provide the first evidence that ECs communicate with SMCs via micro-RNA195 in the regulation of the proliferation of SMCs through 5-HTT, which will contribute to a better understanding of communications between ECs and SMCs via micro-RNA. Our findings suggest a potential target for the control of vessel restenosis. PMID:28272473

  5. Inhibition of the ERK phosphorylation plays a role in terbinafine-induced p21 up-regulation and DNA synthesis inhibition in human vascular endothelial cells

    SciTech Connect

    Ho, P.-Y.; Hsu, S.-P.; Liang, Y.-C.; Kuo, M.-L.; Ho, Y.-S.; Lee, W.-S.

    2008-05-15

    Previously, we showed that terbinafine (TB) induces cell-cycle arrest in cultured human umbilical vein endothelial cells (HUVEC) through an up-regulation of the p21 protein. The aim of this study is to delineate the molecular mechanisms underlying TB-induced increase of p21 protein. RT-PCR analysis demonstrated that the mRNA levels of p21 and p53 were increased in the TB-treated HUVEC. The p21 promoter activity was also increased by TB treatment. Transfection of HUVEC with p53 dominant negative (DN) abolished the TB-induced increases of p21 promoter activity and protein level, suggesting that the TB-induced increase of p21 is p53-dependent. Western blot analysis demonstrated that TB decreased the levels of phosphorylated extracellular signal-regulated kinase (ERK). Over-expression of mitogen-activated protein kinase (MEK)-1, the immediate upstream activator kinase of ERK, abolished the TB-induced increases of p21 and p53 protein and decrease of thymidine incorporation. The ERK inhibitor (PD98059) enhanced the TB-induced inhibition of thymidine incorporation into HUVEC. Taken together, these data suggest that the decrease of ERK activity plays a role in the TB-induced up-regulation of p21 in HUVEC. On the other hand, pretreatment of the cells with geranylgeraniol (GGOH), farnesol (FOH), or Ras inhibitor peptide did not affect the TB-induced decrease of thymidine incorporation. Taken together, our results suggest that TB might cause a decrease of MEK, which in turn up-regulates p53 through the inhibition of ERK phosphorylation, and finally causes an increase of p21 expression and cell-cycle arrest.

  6. Circulating plasma vascular endothelial growth factor and microvascular complications of type 1 diabetes mellitus: the influence of ACE inhibition.

    PubMed

    Chaturvedi, N; Fuller, J H; Pokras, F; Rottiers, R; Papazoglou, N; Aiello, L P

    2001-04-01

    To determine whether circulating plasma vascular endothelial growth factor (VEGF) is elevated in the presence of diabetic microvascular complications, and whether the impact of angiotensin-converting enzyme (ACE) inhibitors on these complications can be accounted for by changes in circulating VEGF. Samples (299/354 of those with retinal photographs) from the EUCLID placebo-controlled clinical trial of the ACE inhibitor lisinopril in mainly normoalbuminuric non-hypertensive Type 1 diabetic patients were used. Albumin excretion rate (AER) was measured 6 monthly. Geometric mean VEGF levels by baseline retinopathy status, change in retinopathy over 2 years, and by treatment with lisinopril were calculated. No significant correlation was observed between VEGF at baseline and age, diabetes duration, glycaemic control, blood pressure, smoking, fibrinogen and von Willebrand factor. Mean VEGF concentration at baseline was 11.5 (95% confidence interval 6.0--27.9) pg/ml in those without retinopathy, 12.9 (6.0--38.9) pg/ml in those with non-proliferative retinopathy, and 16.1 (8.1--33.5) pg/ml in those with proliferative retinopathy (P = 0.06 for trend). Baseline VEGF was 15.2 pg/ml in those who progressed by at least one level of retinopathy by 2 years compared to 11.8 pg/ml in those who did not (P = 0.3). VEGF levels were not altered by lisinopril treatment. Results were similar for AER. Circulating plasma VEGF concentration is not strongly correlated with risk factor status or microvascular disease in Type 1 diabetes, nor is it affected by ACE inhibition. Changes in circulating VEGF cannot account for the beneficial effect of ACE inhibition on retinopathy.

  7. Pentoxifylline inhibits hypoxia-induced upregulation of tumor cell tissue factor and vascular endothelial growth factor.

    PubMed

    Amirkhosravi, A; Meyer, T; Warnes, G; Amaya, M; Malik, Z; Biggerstaff, J P; Siddiqui, F A; Sherman, P; Francis, J L

    1998-10-01

    Tissue factor (TF), the membrane glycoprotein that initiates blood coagulation, is constitutively expressed by many tumor cells and is implicated in peri-tumor fibrin deposition and hypercoagulability in cancer. Upregulation of tumor TF correlates with enhanced metastatic potential. Furthermore, TF has been colocalized with VEGF in breast cancer, specially at sites of early angiogenesis. There are no data on the effect of hypoxia on tumor cell TF expression. Since hypoxia is known to stimulate VEGF production, we studied whether this also induces tumor cell TF expression. Confluent monolayers of A375 melanoma, MCF-7 breast carcinoma and A549 lung carcinoma were cultured in either 95% air, 5% CO2 (normoxic) or 95% N2, 5% CO2 (hypoxic; 25-30 mmHg) for 24 h. Procoagulant activity (PCA) was measured by amidolytic and clotting assays, surface TF antigen by flow cytometry, early apoptosis by annexin V binding and VEGF levels in culture supernatants by ELISA. Hypoxia significantly increased tumor cell PCA in all three cell lines tested and TF antigen on A375 cells was increased four-fold (P <0.05). Pentoxifylline (PTX), a methylxanthine derivative, significantly inhibited the hypoxia-induced increase in PCA as well as VEGF release in all three cell lines tested. In A375 cells, PTX significantly inhibited TF antigen expression by both normoxic and hypoxic cells. Hypoxia induced a slight (5%) but not significant, increase in early apoptosis. Intravenous injection of hypoxic A375 cells into nude rats produced more pronounced thrombocytopenia (n = 5, P <0.01) and more lung metastases (n = 3, P <0.05) compared to normoxic cells. We conclude that hypoxia increases TF expression by malignant cells which enhances tumor cell-platelet binding and hematogenous metastasis. Hypoxia-induced upregulation of TF appears to parallel that of VEGF, although the mechanism remains unclear.

  8. Docosahexaenoic acid inhibits vascular endothelial growth factor (VEGF)-induced cell migration via the GPR120/PP2A/ERK1/2/eNOS signaling pathway in human umbilical vein endothelial cells.

    PubMed

    Chao, Che-Yi; Lii, Chong-Kuei; Ye, Siou-Yu; Li, Chien-Chun; Lu, Chia-Yang; Lin, Ai-Hsuan; Liu, Kai-Li; Chen, Haw-Wen

    2014-05-07

    Cell migration plays an important role in angiogenesis and wound repair. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen that is essential for endothelial cell survival, proliferation, and migration. Docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid, shows both anti-inflammatory and antioxidant activities in vitro and in vivo. This study investigated the molecular mechanism by which DHA down-regulates VEGF-induced cell migration. HUVECs were used as the study model, and the MTT assay, Western blot, wound-healing assay, and phosphatase activity assay were used to explore the effects of DHA on cell migration. GPR120 is the putative receptor for DHA action. The results showed that DHA, PD98059 (an ERK1/2 inhibitor), and GW9508 (a GPR120 agonist) inhibited VEGF-induced cell migration. In contrast, pretreatment with okadaic acid (OA, a PP2A inhibitor) and S-nitroso-N-acetyl-DL-penicillamine (an NO donor) reversed the inhibition of cell migration by DHA. VEGF-induced cell migration was accompanied by phosphorylation of ERK1/2 and eNOS. Treatment of HUVECs with DHA increased PP2A enzyme activity and decreased VEGF-induced phosphorylation of ERK1/2 and eNOS. However, pretreatment with OA significantly decreased DHA-induced PP2A enzyme activity and reversed the DHA inhibition of VEGF-induced ERK1/2 and eNOS phosphorylation. These results suggest that stimulation of PP2A activity and inhibition of the VEGF-induced ERK1/2/eNOS signaling pathway may be involved in the DHA suppression of VEGF-induced cell migration. Thus, the effect of DHA on angiogenesis and wound repair is at least partly by virtue of its attenuation of cell migration.

  9. Vaccarin attenuates the human EA.hy926 endothelial cell oxidative stress injury through inhibition of Notch signaling.

    PubMed

    Xie, Fengshan; Cai, Weiwei; Liu, Yanling; Li, Yue; Du, Bin; Feng, Lei; Qiu, Liying

    2015-01-01

    Endothelial cell injury is an essential component of atherosclerosis and hypertension. Atherosclerosis and other macrovascular diseases are the most common complications of diabetes. Vaccarin is a major flavonoid glycoside in Vaccariae semen, and is expected to be useful in the treatment of vascular diseases. The aim of the present study was to evaluate the possible effects of vaccarin in human umbilical vein endothelial cells (EA.hy926) induced by hydrogen peroxide (H2O2) and its underlying mechanism in the prevention and treatment of H2O2 injury. In this study, the EA.hy926 cells were exposed to 250, 500 and 1000 µM H2O2 for 2 and 4 h in the absence or presence of vaccarin, and the cell injury induced by H2O2 was examined via SRB. Cell migratory ability, lactate dehydrogenase (LDH) leakage, malondialdehyde (MDA) levels and decreasing superoxide dismutase (SOD) activity were evaluated by the wound healing assay and corresponding assay kits. Cell apoptosis was detected by flow cytometry with Annexin V-fluorescein isothiocyanate/propidium iodide Apoptosis Detection kit and Hoechst staining. Furthermore, western blot detected the protein expressions of Notch1, Hes1 and caspase-3. Following treatment with H2O2, it was found that H2O2 stimulated cell injury in a dose-dependent manner, including reducing cell viability and cell migratory ability, increasing LDH leakage and MDA levels, and decreasing SOD activity. H2O2 further accelerated cell apoptosis via activation of Notch1 and the downstream molecule Hes1. Preincubation with vaccarin was found to protect EA.hy926 cells from H2O2-induced cell oxidative stress injury, which promoted cell viability and cell migratory ability, inhibited the level of LDH and MDA, but enhanced the activity of SOD. In particular, in addition to downregulation Notch signaling, vaccarin treatments also downregulated caspase-3, a cell apoptotic pathway-related protein. These findings indicated that vaccarin may be able to selectively protect

  10. Delivery of Small Interfering RNA to Inhibit Vascular Endothelial Growth Factor in Zebrafish Using Natural Brain Endothelia Cell-Secreted Exosome Nanovesicles for the Treatment of Brain Cancer.

    PubMed

    Yang, Tianzhi; Fogarty, Brittany; LaForge, Bret; Aziz, Salma; Pham, Thuy; Lai, Leanne; Bai, Shuhua

    2017-03-01

    Although small interfering RNA (siRNA) holds great therapeutic promise, its delivery to the disease site remains a paramount obstacle. In this study, we tested whether brain endothelial cell-derived exosomes could deliver siRNA across the blood-brain barrier (BBB) in zebrafish. Natural exosomes were isolated from brain endothelial bEND.3 cell culture media and vascular endothelial growth factor (VEGF) siRNA was loaded in exosomes with the assistance of a transfection reagent. While fluorescence-activated cell flow cytometry and immunocytochemistry staining studies indicated that wild-type exosomes significantly increased the uptake of fluorescence-labeled siRNA in the autologous brain endothelial cells, decreased fluorescence intensity was observed in the cells treated with the tetraspanin CD63 antibody-blocked exosome-delivered formulation (p < 0.05). In the transport study, exosomes also enhanced the permeability of rhodamine 123 in a co-cultured monolayer of brain endothelial bEND.3 cell and astrocyte. Inhibition at the expression of VEGF RNA and protein levels was observed in glioblastoma-astrocytoma U-87 MG cells treated with exosome-delivered siRNAs. Imaging results showed that exosome delivered more siRNAs across the BBB in Tg(fli1:GFP) zebrafish. In a xenotransplanted brain tumor model, exosome-delivered VEGF siRNAs decreased the fluorescence intensity of labeled cancer cells in the brain of zebrafish. Brain endothelial cell-derived exosomes could be potentially used as a natural carrier for the brain delivery of exogenous siRNA.

  11. Novel angiogenic inhibitor DN-9693 that inhibits post-transcriptional induction of connective tissue growth factor (CTGF/CCN2) by vascular endothelial growth factor in human endothelial cells.

    PubMed

    Kondo, Seiji; Tanaka, Noriko; Kubota, Satoshi; Mukudai, Yoshiki; Yosimichi, Gen; Sugahara, Toshio; Takigawa, Masaharu

    2006-01-01

    Connective tissue growth factor (CTGF/CCN2) is a potent angiogenic factor. In this report, we describe for the first time that vascular endothelial growth factor (VEGF)-mediated induction of the ctgf/ccn2 gene was a post-transcriptional event that was inhibited by a novel angiogenic inhibitor, DN-9693, in human umbilical vein endothelial cells. Steady-state mRNA levels of ctgf/ccn2 were remarkably increased by VEGF in a concentration-dependent manner, whereas the activity of the ctgf/ccn2 promoter was not responsive to VEGF as confirmed by a reporter gene assay and quantitative real-time PCR analysis. By employing a RNA degradation assay, we eventually found that the observed increase in the ctgf/ccn2 mRNA level was due to an increased stability of the mRNA induced by VEGF. DN-9693 at a dose of 0.1 to 2 ng/mL did not affect basal levels of ctgf/ccn2 mRNA; however, enhancement of ctgf/ccn2 mRNA expression by VEGF was specifically inhibited by DN-9693. Of importance, the inhibitory effects could be also ascribed to post-transcriptional regulation, because the VEGF-mediated increase in stability of ctgf/ccn2 mRNA was suppressed by DN-9693. Furthermore, we investigated the effects of DN-9693 on VEGF-induced activation of three subgroups of mitogen-activated protein kinase pathways and found that DN-9693 blocked the activation of these pathways by VEGF. These results suggest that VEGF increases ctgf/ccn2 mRNA stability through mitogen-activated protein kinase-mediated intracellular signaling cascade(s), which can be inhibited posttranscriptionally by a novel angiogenic inhibitor, DN-9693, in human umbilical vein endothelial cells.

  12. Cediranib, a pan-VEGFR inhibitor, and olaparib, a PARP inhibitor, in combination therapy for high grade serous ovarian cancer.

    PubMed

    Ivy, S Percy; Liu, Joyce F; Lee, Jung-Min; Matulonis, Ursula A; Kohn, Elise C

    2016-01-01

    An estimated 22,000 women are diagnosed annually with ovarian cancer in the United States. Initially chemo-sensitive, recurrent disease ultimately becomes chemoresistant and may kill ~14,000 women annually. Molecularly targeted therapy with cediranib (AZD2171), a vascular endothelial growth factor receptor (VEGFR)-1, 2, and 3 signaling blocker, and olaparib (AZD2281), a poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitor, administered orally in combination has shown anti-tumor activity in the treatment of high grade serous ovarian cancer (HGSOC). This combination has the potential to change the treatment of HGSOC. Preclinical and clinical studies of single agent cediranib and olaparib or their combination are reviewed. Data are presented from peer-reviewed published manuscripts, completed and ongoing early phase clinical trials registered in ClinicalTrials.gov, National Cancer Institute-sponsored clinical trials, and related recent abstracts. Advances in the treatment of HGSOC that improve progression-free and overall survival have proven elusive despite examination of molecularly targeted therapy. HGSOC patients with deleterious germline or somatic mutations in BRCA1 or BRCA2 (BRCAm) are most responsive to PARP inhibitors (PARPi). PARPi combined with angiogenesis inhibition improved anti-cancer response and duration in both BRCAm and BRCA wild type HGSOC patients, compared to olaparib single agent treatment, demonstrating therapeutic chemical and contextual synthetic lethality.

  13. The anticancer effects of chaetocin are independent of programmed cell death and hypoxia, and are associated with inhibition of endothelial cell proliferation

    PubMed Central

    Isham, C R; Tibodeau, J D; Bossou, A R; Merchan, J R; Bible, K C

    2012-01-01

    Background: We previously reported that chaetocin has potent and selective anti-myeloma activity attributable to reactive oxygen species (ROS) induction imposed by inhibition of the redox enzyme thioredoxin reductase; we now detail its effects in solid tumours. Methods: Cellular assays, transcriptional profiling and the NCI60 screen were used to assess the effects of chaetocin in solid tumour and endothelial cells. Results: NCI-60 screening demonstrated chaetocin to even more potently inhibit proliferation in solid tumour than in haematological cell lines; transcriptional profiling revealed a signature consistent with induction of inflammatory response and cell death pathways. Chaetocin induced ROS, oxidative damage to cellular proteins and apoptosis, with 2–10 n IC50s (24 h exposures) in all tested solid tumour cell lines. The pan-caspase inhibitor zVAD-fmk did not block chaetocin-induced cell death despite inhibiting mitochondrial membrane depolarisation and apoptosis. Further, Molt-4 rho0 cells lacking metabolically functional mitochondria were readily killed by chaetocin; in addition chaetocin-induced cytotoxicity was unaffected by autophagy inhibitors or hypoxia and consequent HIF-1α upregulation. Moreover, chaetocin inhibited SKOV3 ovarian cancer xenografts producing less vascular tumours, and inhibited human umbilical vein endothelial cell proliferation. Conclusion: Chaetocin has intriguing and wide-ranging in vitro and in vivo anticancer effects, and is an attractive candidate for further preclinical and clinical development. PMID:22187030

  14. Diallyl trisulfide inhibits migration, invasion and angiogenesis of human colon cancer HT-29 cells and umbilical vein endothelial cells, and suppresses murine xenograft tumour growth.

    PubMed

    Lai, Kuang-Chi; Hsu, Shu-Chun; Yang, Jai-Sing; Yu, Chien-Chih; Lein, Jin-Cherng; Chung, Jing-Gung

    2015-02-01

    Angiogenesis inhibitors are beneficial for the prevention and treatment of angiogenesis-dependent diseases including cancer. We examined the cytotoxic, anti-metastatic, anti-cancer and anti-angiogenic effects of diallyl trisulfide (DATS). In HT29 cells, DATS inhibited migration and invasion through the inhibition of focal adhesion kinase (FAK), extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38 which was associated with inhibition of matrix metalloproteinases-2, -7 and -9 and VEGF. In human umbilical vein endothelial cells (HUVEC), DATS inhibited the migration and angiogenesis through FAK, Src and Ras. DATS also inhibited the secretion of VEGF. The capillary-like tube structure formation and migration by HUVEC was inhibited by DATS. The chicken egg chorioallantoic membrane (CAM) assay indicated that DATS treatment inhibited ex-vivo angiogenesis. We investigated the anti-tumour effects of DATS against human colon cancer xenografts in BALB/c(nu/nu) mice and its anti-angiogenic activity in vivo. In this in-vivo study, DATS also inhibited the tumour growth, tumour weight and angiogenesis (decreased the levels of haemoglobin) in HT29 cells. In conclusion, the present results suggest that the inhibition of angiogenesis may be an important mechanism in colon cancer chemotherapy by DATS. © 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  15. Diallyl trisulfide inhibits migration, invasion and angiogenesis of human colon cancer HT-29 cells and umbilical vein endothelial cells, and suppresses murine xenograft tumour growth

    PubMed Central

    Lai, Kuang-Chi; Hsu, Shu-Chun; Yang, Jai-Sing; Yu, Chien-Chih; Lein, Jin-Cherng; Chung, Jing-Gung

    2015-01-01

    Angiogenesis inhibitors are beneficial for the prevention and treatment of angiogenesis-dependent diseases including cancer. We examined the cytotoxic, anti-metastatic, anti-cancer and anti-angiogenic effects of diallyl trisulfide (DATS). In HT29 cells, DATS inhibited migration and invasion through the inhibition of focal adhesion kinase (FAK), extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38 which was associated with inhibition of matrix metalloproteinases-2, -7 and -9 and VEGF. In human umbilical vein endothelial cells (HUVEC), DATS inhibited the migration and angiogenesis through FAK, Src and Ras. DATS also inhibited the secretion of VEGF. The capillary-like tube structure formation and migration by HUVEC was inhibited by DATS. The chicken egg chorioallantoic membrane (CAM) assay indicated that DATS treatment inhibited ex-vivo angiogenesis. We investigated the anti-tumour effects of DATS against human colon cancer xenografts in BALB/cnu/nu mice and its anti-angiogenic activity in vivo. In this in-vivo study, DATS also inhibited the tumour growth, tumour weight and angiogenesis (decreased the levels of haemoglobin) in HT29 cells. In conclusion, the present results suggest that the inhibition of angiogenesis may be an important mechanism in colon cancer chemotherapy by DATS. PMID:25403643

  16. Impact of DPP-4 inhibition on acute and chronic endothelial function in humans with type 2 diabetes on background metformin therapy.

    PubMed

    Widlansky, Michael E; Puppala, Venkata K; Suboc, Tisha M; Malik, Mobin; Branum, Amberly; Signorelli, Kara; Wang, Jingli; Ying, Rong; Tanner, Michael J; Tyagi, Sudhi

    2017-01-01

    Cell culture and animal work indicate that dipeptidyl peptidase-4 (DPP-4) inhibition may exert cardiovascular benefits through favorable effects on the vascular endothelium. Prior human studies evaluating DPP-4 inhibition have shown conflicting results that may in part be related to heterogeneity of background anti-diabetes therapies. No study has evaluated the acute response of the vasculature to DPP-4 inhibition in humans. We recruited 38 patients with type 2 diabetes on stable background metformin therapy for a randomized, double-blind, placebo-controlled crossover trial of DPP-4 inhibition with sitagliptin (100 mg/day). Each treatment period was 8 weeks long separated by 4 weeks of washout. Endothelial function and plasma markers of endothelial activation (intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1)) were measured prior to and 2 hours following acute dosing of sitagliptin or placebo, as well as following 8 weeks of intervention with each pill. Thirty subjects completed the study and were included in analyses. Neither acute nor chronic sitagliptin therapy resulted in significant changes in vascular endothelial function. While post-acute sitagliptin ICAM-1 levels were lower than that post-chronic sitagliptin, the ICAM-1 concentration was not significantly different than pre-acute sitagliptin levels or levels measured in relationship to placebo. There were no significant changes in plasma VCAM-1 levels at any time point. Acute and chronic sitagliptin therapies have neutral effects on the vascular endothelium in the setting of metformin background therapy. In conclusion, our findings suggest DPP-4 inhibition has a neutral effect on cardiovascular risk in patients without a history of heart failure or renal insufficiency.

  17. Vaccarin attenuates high glucose-induced human EA•hy926 endothelial cell injury through inhibition of Notch signaling.

    PubMed

    Qiu, Yuyu; Du, Bin; Xie, Fengshan; Cai, Weiwei; Liu, Yanling; Li, Yue; Feng, Lei; Qiu, Liying

    2016-03-01

    Endothelial cell injury is a critical component of atherosclerosis and hypertension. Vaccarin is considered to be of potential benefit in the treatment of vascular diseases. The aim of the present study was to evaluate the possible effects of vaccarin in human EA·hy926 cells induced by high glucose, and to investigate its underlying mechanism in the prevention and treatment of high glucose‑induced injury. In the present study, EA·hy926 cells were exposed to 90, 180 and 270 mM high glucose for 24 h, and the induced cell injury was examined using a sulforhodamine B assay. Following treatment with high glucose, it was found that high glucose stimulated cell injury, resulting in reduced cell viability and migratory ability, increased lactate dehydrogenase (LDH) leakage and malondialdehyde (MDA) levels, and decreased superoxide dismutase (SOD) activity. High glucose further accelerated cell apoptosis via activating Notch1 and Hairy and enhancer of split 1. It was found that preincubation with vaccarin protected the EA·hy926 cells from high glucose‑induced cell injury, which promoted cell viability and migratory ability, inhibited the expression levels of LDH and MDA, and enhanced the activity of SOD. Cell migratory ability, LDH leakage, MDA levels and decreasing SOD activity were evaluated using a wound healing assay and corresponding assay kits. Cell apoptosis was detected by flow cytometry with an Annexin V‑fluorescein isothiocyanate/propidium iodide apoptosis detection kit and Hoechst staining. Furthermore, western blotting was used to detect the protein expression levels of Notch1, Hes1 and caspase‑3. In particular, in addition to inducing the downregulation of Notch signaling, vaccarin treatment downregulated the cell apoptotic pathway‑associated protein caspase 3. These findings suggested that vaccarin may be able to selectively protect the vascular endothelium from dysfunction induced by high glucose.

  18. Inhibition of vascular endothelial growth factor by small interfering RNA upregulates differentiation, maturation and function of dendritic cells

    PubMed Central

    WANG, HAIYAN; ZHANG, LUPING; ZHANG, SHAOYAN; LI, YANNIAN

    2015-01-01

    This study aimed to investigate the effects of vascular endothelial growth factor (VEGF) secreted by MCF-7 breast cancer cells on the differentiation, maturation and function of dendritic cells (DCs). Small interfering RNAs (siRNAs) directed against the VEGF gene were designed and transfected into MCF-7 breast cancer cells at an optimal concentration (100 nmol/l) using cationic liposome transfection reagent, whereas the control group was transfected with only transfection reagent. Western blot analysis and ELISA were used to determine VEGF protein expression and VEGF concentration, respectively. Mononuclear cells were cultured with the culture supernatants from primary MCF-7 cells (control group) and siRNA-treated MCF-7 cells (siRNA group). The DC phenotypes, including CD1a, CD80, CD83, CD86 and HLA-DR, were evaluated by flow cytometry. The MTT assay was used to assess the cytotoxicity of DC-mediated tumor-specific cytotoxic T lymphocytes (CTLs) against MCF-7 cells in the two different culture supernatants. The VEGF-targeted constructed siRNA inhibited VEGF expression in MCF-7 cells. Cultivation with the culture supernatants from MCF-7 cells treated with siRNA affected DC morphology. DCs in the siRNA group exhibited a significantly higher expression of CD86, CD80, CD83 and HLA-DR compared to the cells in the control group, whereas the expression of CD1a in the siRNA group was significantly lower compared to that in the control group. The cytotoxic activity of CTLs mediated by DCs was significantly altered by siRNA transfection. These results indicated that VEGF may play a significant role in tumor development, progression and immunosuppression. PMID:25452786

  19. Inhibition of mTOR down-regulates scavenger receptor, class B, type I (SR-BI) expression, reduces endothelial cell migration and impairs nitric oxide production.

    PubMed

    Fruhwürth, Stefanie; Krieger, Sigurd; Winter, Katharina; Rosner, Margit; Mikula, Mario; Weichhart, Thomas; Bittman, Robert; Hengstschläger, Markus; Stangl, Herbert

    2014-07-01

    The mammalian target of rapamycin (mTOR) inhibiting drug rapamycin (Sirolimus) has severe side effects in patients including hyperlipidemia, an established risk factor for atherosclerosis. Recently, it was shown that rapamycin decreases hepatic LDL receptor (LDL-R) expression, which likely contributes to hypercholesterolemia. Scavenger receptor, class B, type I (SR-BI) is the major HDL receptor and consequently regulating HDL-cholesterol levels and the athero-protective effects of HDL. By using the mTOR inhibitor rapamycin, we show that SR-BI is down-regulated in human umbilical vein endothelial cells (HUVECs). This reduction of SR-BI protein as well as mRNA levels by about 50% did not alter HDL particle uptake or HDL-derived lipid transfer. However, rapamycin reduced HDL-induced activation of eNOS and stimulation of endothelial cell migration. The effects on cell migration could be counteracted by SR-BI overexpression, indicating that decreased SR-BI expression is in part responsible for the rapamycin-induced effects. We demonstrate that inhibition of mTOR leads to endothelial cell dysfunction and decreased SR-BI expression, which may contribute to atherogenesis during rapamycin treatment.

  20. Increased expression of microRNA-221 inhibits PAK1 in endothelial progenitor cells and impairs its function via c-Raf/MEK/ERK pathway

    SciTech Connect

    Zhang, Xiaoping; Mao, Haian; Chen, Jin-yuan; Wen, Shengjun; Li, Dan; Ye, Meng; Lv, Zhongwei

    2013-02-15

    Highlights: ► MicroRNA-221 is upregulated in the endothelial progenitor cells of atherosclerosis patients. ► PAK1 is a direct target of microRNA-221. ► MicroRNA-221 inhibits EPCs proliferation through c-Raf/MEK/ERK pathway. -- Abstract: Coronary artery disease (CAD) is associated with high mortality and occurs via endothelial injury. Endothelial progenitor cells (EPCs) restore the integrity of the endothelium and protect it from atherosclerosis. In this study, we compared the expression of microRNAs (miRNAs) in EPCs in atherosclerosis patients and normal controls. We found that miR-221 expression was significantly up-regulated in patients compared with controls. We predicted and identified p21/Cdc42/Rac1-activated kinase 1 (PAK1) as a novel target of miR-221 in EPCs. We also demonstrated that miR-221 targeted a putative binding site in the 3′UTR of PAK1, and absence of this site was inversely associated with miR-221 expression in EPCs. We confirmed this relationship using a luciferase reporter assay. Furthermore, overexpression of miR-221 in EPCs significantly decreased EPC proliferation, in accordance with the inhibitory effects induced by decreased PAK1. Overall, these findings demonstrate that miR-221 affects the MEK/ERK pathway by targeting PAK1 to inhibit the proliferation of EPCs.

  1. Neuronal cell death in the inner retina and the influence of vascular endothelial growth factor inhibition in a diabetic rat model.

    PubMed

    Park, Hae-Young Lopilly; Kim, Jie Hyun; Park, Chan Kee

    2014-06-01

    To inhibit vascular changes in diabetic retinopathy, inhibiting vascular endothelial growth factor (VEGF) has become a mainstay of the treatment of diabetic retinopathy. However, its effects on neuronal cells remain to be elucidated. We aimed to evaluate the effect of VEGF inhibition on neuronal cells in a streptozotocin-induced diabetic rat retina. VEGF inhibition was performed by intravitreal VEGF-A antibody injection. After anti-VEGF treatment, apoptosis in retinal ganglion cells (RGCs) increased, and novel apoptosis in amacrine and bipolar cells of the inner nuclear layer was observed by TUNEL staining. Phosphorylated Akt expression was significantly higher in RGCs but was decreased in neuronal cells of the inner nuclear layer after anti-VEGF treatment by Western blot analysis and immunohistochemical staining. These results demonstrate that VEGF inhibition significantly increased RGC apoptosis and neuronal cell apoptosis in the inner nuclear layer of a diabetic retina, which seems to consist primarily of amacrine and bipolar cells. The phosphorylated Akt pathway, which plays a neuroprotective role via VEGF, was significantly affected by VEGF inhibition in the inner nuclear layer, suggesting that neurotrophic factor deprivation is the main mechanism for neuronal cell death after inhibiting VEGF. The results of this study show that inhibiting VEGF may have detrimental effects on the apoptosis of neuronal cells in the inner layers of the diabetic retina.

  2. Inhibition of Vascular Endothelial Growth Factor A and Hypoxia-Inducible Factor 1α Maximizes the Effects of Radiation in Sarcoma Mouse Models Through Destruction of Tumor Vasculature

    SciTech Connect

    Lee, Hae-June; Yoon, Changhwan; Park, Do Joong; Kim, Yeo-Jung; Schmidt, Benjamin; Lee, Yoon-Jin; Tap, William D.; Eisinger-Mathason, T.S. Karin; Choy, Edwin; Kirsch, David G.; Simon, M. Celeste; and others

    2015-03-01

    Purpose: To examine the addition of genetic or pharmacologic inhibition of hypoxia-inducible factor 1α (HIF-1α) to radiation therapy (RT) and vascular endothelial growth factor A (VEGF-A) inhibition (ie trimodality therapy) for soft-tissue sarcoma. Methods and Materials: Hypoxia-inducible factor 1α was inhibited using short hairpin RNA or low metronomic doses of doxorubicin, which blocks HIF-1α binding to DNA. Trimodality therapy was examined in a mouse xenograft model and a genetically engineered mouse model of sarcoma, as well as in vitro in tumor endothelial cells (ECs) and 4 sarcoma cell lines. Results: In both mouse models, any monotherapy or bimodality therapy resulted in tumor growth beyond 250 mm{sup 3} within the 12-day treatment period, but trimodality therapy with RT, VEGF-A inhibition, and HIF-1α inhibition kept tumors at <250 mm{sup 3} for up to 30 days. Trimodality therapy on tumors reduced HIF-1α activity as measured by expression of nuclear HIF-1α by 87% to 95% compared with RT alone, and cytoplasmic carbonic anhydrase 9 by 79% to 82%. Trimodality therapy also increased EC-specific apoptosis 2- to 4-fold more than RT alone and reduced microvessel density by 75% to 82%. When tumor ECs were treated in vitro with trimodality therapy under hypoxia, there were significant decreases in proliferation and colony formation and increases in DNA damage (as measured by Comet assay and γH2AX expression) and apoptosis (as measured by cleaved caspase 3 expression). Trimodality therapy had much less pronounced effects when 4 sarcoma cell lines were examined in these same assays. Conclusions: Inhibition of HIF-1α is highly effective when combined with RT and VEGF-A inhibition in blocking sarcoma growth by maximizing DNA damage and apoptosis in tumor ECs, leading to loss of tumor vasculature.

  3. Inhibition of Rho-kinase protects cerebral barrier from ischaemia-evoked injury through modulations of endothelial cell oxidative stress and tight junctions.

    PubMed

    Gibson, Claire L; Srivastava, Kirtiman; Sprigg, Nikola; Bath, Philip M W; Bayraktutan, Ulvi

    2014-06-01

    Ischaemic strokes evoke blood-brain barrier (BBB) disruption and oedema formation through a series of mechanisms involving Rho-kinase activation. Using an animal model of human focal cerebral ischaemia, this study assessed and confirmed the therapeutic potential of Rho-kinase inhibition during the acute phase of stroke by displaying significantly improved functional outcome and reduced cerebral lesion and oedema volumes in fasudil- versus vehicle-treated animals. Analyses of ipsilateral and contralateral brain samples obtained from mice treated with vehicle or fasudil at the onset of reperfusion plus 4 h post-ischaemia or 4 h post-ischaemia alone revealed these benefits to be independent of changes in the activity and expressions of oxidative stress- and tight junction-related parameters. However, closer scrutiny of the same parameters in brain microvascular endothelial cells subjected to oxygen-glucose deprivation ± reperfusion revealed marked increases in prooxidant NADPH oxidase enzyme activity, superoxide anion release and in expressions of antioxidant enzyme catalase and tight junction protein claudin-5. Cotreatment of cells with Y-27632 prevented all of these changes and protected in vitro barrier integrity and function. These findings suggest that inhibition of Rho-kinase after acute ischaemic attacks improves cerebral integrity and function through regulation of endothelial cell oxidative stress and reorganization of intercellular junctions. Inhibition of Rho-kinase (ROCK) activity in a mouse model of human ischaemic stroke significantly improved functional outcome while reducing cerebral lesion and oedema volumes compared to vehicle-treated counterparts. Studies conducted with brain microvascular endothelial cells exposed to OGD ± R in the presence of Y-27632 revealed restoration of intercellular junctions and suppression of prooxidant NADPH oxidase activity as important factors in ROCK inhibition-mediated BBB protection. © 2014 International Society

  4. Inhibition of cell surface expression of endothelial adhesion molecules by ursolic acid prevents intimal hyperplasia of venous bypass grafts in rats

    PubMed Central

    Zeller, Iris; Wiedemann, Dominik; Schwaiger, Stefan; Stelzmüller, Marlies; Kreutmayer, Simone; Leberfing, Oliver; Stuppner, Hermann; Bernhard, David

    2012-01-01

    OBJECTIVES Despite rapid progress in surgical techniques, there is still a significant lack of surgery-supportive pharmacological treatments. The aim of this study was to test the hypothesis that ursolic acid (UA) may prevent intimal hyperplasia of venous bypass grafts. METHODS The hypothesis was tested by means of primary cell isolation and culture followed by real-time polymerase chain reaction, western blotting, fluorescence microscopy and fluorescence-activated cell sorting analyses, as well as an in vivo rat model for intimal hyperplasia of venous bypass grafts and immunohistochemistry and histochemistry. RESULTS The local application of UA significantly inhibited intimal hyperplasia in vivo (intimal thickness control: 25 μm, UA group: 18 μM–8 weeks after surgery). The UA treatment of grafts significantly resulted in reduced endothelial vascular cell adhesion molecule-1 (VCAM-1) expression, reduced infiltration of the grafts vessel wall by CD45-positive cells and increased smooth muscle cell (SMC) death. In in vitro condition, it could be shown that UA inhibits VCAM-1 expression downstream of NFκB and is likely to interfere with VCAM-1 protein synthesis in endothelial cells. Quantification of cell death in vascular smooth muscle cells treated with UA indicated that UA is a potent inducer of SMC apoptosis. CONCLUSIONS Our results suggest that UA-mediated inhibition of endothelial VCAM-1 expression reduces the infiltration of venous bypass grafts by CD45-positive cells and inhibits intimal hyperplasia. Apoptosis induction in SMCs may be another method in which UA reduces intimal thickening. UA may constitute a surgery-supportive pharmacon that reduces intimal hyperplasia of vein grafts. PMID:22551965

  5. Procyanidin B2 3,3″-di-O-gallate inhibits endothelial cells growth and motility by targeting VEGFR2 and integrin signaling pathways.

    PubMed

    Kumar, Rahul; Deep, Gagan; Wempe, Michael F; Agarwal, Rajesh; Agarwal, Chapla

    2015-01-01

    Targeting angiogenesis, one of the hallmarks of carcinogenesis, using non-toxic phytochemicals has emerged as a translational opportunity for angioprevention and to control advanced stages of malignancy. Herein, we investigated the inhibitory effects and associated mechanism/s of action of Procyanidin B2-3,3″-di- O-gallate (B2G2), a major component of grape seed extract, on human umbilical vein endothelial cells (HUVECs) and human prostate microvascular endothelial cells (HPMECs). Our results showed that B2G2 (10-40 μM) inhibits growth and induces death in both HUVECs and HPMECs. Additional studies revealed that B2G2 causes a G1 arrest in cell cycle progression of HUVECs by down-regulating cyclins (D1 and A), CDKs (Cdk2 and Cdc2) and Cdc25c phosphatase and up-regulating CDK inhibitors (p21 and p27) expression. B2G2 also induced strong apoptotic death in HUVECs through increasing p53, Bax and Smac/Diablo expression while decreasing Bcl-2 and survivin levels. Additionally, B2G2 inhibited the growth factors-induced capillary tube formation in HUVECs and HPMECs. Interestingly, conditioned media (CCM) from prostate cancer (PCA) cells (LNCaP and PC3) grown under normoxic (~21% O2) and hypoxic (1% O2) conditions significantly enhanced the tube formation in HUVECs, which was compromised in presence of conditioned media from B2G2-treated PCA cells. B2G2 also inhibited the motility and invasiveness of both HUVECs and HPMECs. Mechanistic studies showed that B2G2 targets VEGFR2/PI3K/Akt and integrin signaling molecules which are important for endothelial cells survival, proliferation, tube formation and motility. Overall, we report that B2G2 inhibits several attributes of angiogenesis in cell culture; therefore, it warrants further investigation for efficacy for angioprevention and cancer control.

  6. EGCG protects endothelial cells against PCB 126-induced inflammation through inhibition of AhR and induction of Nrf2-regulated genes

    PubMed Central

    Han, Sung Gu; Han, Seong-Su; Toborek, Michal; Hennig, Bernhard

    2012-01-01

    Tea flavonoids such as epigallocatechin gallate (EGCG) protect against vascular diseases such as atherosclerosis via their antioxidant and anti-inflammatory functions. Persistent and widespread environmental pollutants, including polychlorinated biphenyls (PCB), can induce oxidative stress and inflammation in vascular endothelial cells. Even though PCBs are no longer produced, they are still detected in human blood and tissues and thus considered a risk for vascular dysfunction. We hypothesized that EGCG can protect endothelial cells against PCB-induced cell damage via its antioxidant and anti-inflammatory properties. To test this hypothesis, primary vascular endothelial cells were pretreated with EGCG, followed by exposure to the coplanar PCB 126. Exposure to PCB 126 significantly increased cytochrome P450 1A1 (Cyp1A1) mRNA and protein expression and superoxide production, events which were significantly attenuated following pretreatment with EGCG. Similarly, EGCG also reduced DNA binding of NF-κB and downstream expression of inflammatory markers such as monocyte chemotactic protein-1 (MCP-1) and vascular cell adhesion protein-1 (VCAM-1) after PCB exposure. Furthermore, EGCG decreased endogenous or base-line levels of Cyp1A1, MCP-1 and VCAM-1 in endothelial cells. Most of all, treatment of EGCG upregulated expression of NF-E2-related factor 2 (Nrf2)-controlled antioxidant genes, including glutathione S transferase (GST) and NAD(P)H:quinone oxidoreductase 1 (NQO1), in a dose-dependent manner. In contrast, silencing of Nrf2 increased Cyp1A1, MCP-1 and VCAM-1 and decreased of GST and NQO1 expression, respectively. These data suggest that EGCG can inhibit AhR regulated genes and induce Nrf2-regulated antioxidant enzymes, thus providing protection against PCB-induced inflammatory responses in endothelial cells. PMID:22521609

  7. Endoglin promotes transforming growth factor beta-mediated Smad 1/5/8 signaling and inhibits endothelial cell migration through its association with GIPC.

    PubMed

    Lee, Nam Y; Ray, Bridgette; How, Tam; Blobe, Gerard C

    2008-11-21

    Transforming growth factor beta (TGF-beta) signals through two distinct pathways to regulate endothelial cell proliferation, migration, and angiogenesis, the ALK-1/Smad 1/5/8 and ALK-5/Smad2/3 pathways. Endoglin is a co-receptor predominantly expressed in endothelial cells that participates in TGFbeta-mediated signaling with ALK-1 and ALK-5 and regulates critical aspects of cellular and biological responses. The embryonic lethal phenotype of knock-out mice because of defects in angiogenesis and disease-causing mutations resulting in human vascular diseases both support essential roles for endoglin, ALK-1, and ALK-5 in the vasculature. However, the mechanism by which endoglin mediates TGF-beta signaling through ALK-1 and ALK-5 has remained elusive. Here we describe a novel interaction between endoglin and GIPC, a scaffolding protein known to regulate cell surface receptor expression and trafficking. Co-immunoprecipitation and immunofluorescence confocal studies both demonstrate a specific interaction between endoglin and GIPC in endothelial cells, mediated by a class I PDZ binding motif in the cytoplasmic domain of endoglin. Subcellular distribution studies demonstrate that endoglin recruits GIPC to the plasma membrane and co-localizes with GIPC in a TGFbeta-independent manner, with GIPC-promoting cell surface retention of endoglin. Endoglin specifically enhanced TGF-beta1-induced phosphorylation of Smad 1/5/8, increased a Smad 1/5/8 responsive promoter, and inhibited endothelial cell migration in a manner dependent on the ability of endoglin to interact with GIPC. These studies define a novel mechanism for the regulation of endoglin signaling and function in endothelial cells and demonstrate a new role for GIPC in TGF-beta signaling.

  8. Endoglin Promotes Transforming Growth Factor β-mediated Smad 1/5/8 Signaling and Inhibits Endothelial Cell Migration through Its Association with GIPC*

    PubMed Central

    Lee, Nam Y.; Ray, Bridgette; How, Tam; Blobe, Gerard C.

    2008-01-01

    Transforming growth factor β (TGF-β) signals through two distinct pathways to regulate endothelial cell proliferation, migration, and angiogenesis, the ALK-1/Smad 1/5/8 and ALK-5/Smad2/3 pathways. Endoglin is a co-receptor predominantly expressed in endothelial cells that participates in TGFβ-mediated signaling with ALK-1 and ALK-5 and regulates critical aspects of cellular and biological responses. The embryonic lethal phenotype of knock-out mice because of defects in angiogenesis and disease-causing mutations resulting in human vascular diseases both support essential roles for endoglin, ALK-1, and ALK-5 in the vasculature. However, the mechanism by which endoglin mediates TGF-β signaling through ALK-1 and ALK-5 has remained elusive. Here we describe a novel interaction between endoglin and GIPC, a scaffolding protein known to regulate cell surface receptor expression and trafficking. Co-immunoprecipitation and immunofluorescence confocal studies both demonstrate a specific interaction between endoglin and GIPC in endothelial cells, mediated by a class I PDZ binding motif in the cytoplasmic domain of endoglin. Subcellular distribution studies demonstrate that endoglin recruits GIPC to the plasma membrane and co-localizes with GIPC in a TGFβ-independent manner, with GIPC-promoting cell surface retention of endoglin. Endoglin specifically enhanced TGF-β1-induced phosphorylation of Smad 1/5/8, increased a Smad 1/5/8 responsive promoter, and inhibited endothelial cell migration in a manner dependent on the ability of endoglin to interact with GIPC. These studies define a novel mechanism for the regulation of endoglin signaling and function in endothelial cells and demonstrate a new role for GIPC in TGF-β signaling. PMID:18775991

  9. A Preliminary Study of the Therapeutic Role of Human Early Fetal Aorta-derived Endothelial Progenitor Cells in Inhibiting Carotid Artery Neointimal Hyperplasia.

    PubMed

    Xu, Rong-Wei; Zhang, Wen-Jian; Zhang, Jian-Bin; Wen, Jian-Yan; Wang, Meng; Liu, Hong-Lin; Pan, Lin; Yu, Chang-An; Lou, Jin-Ning; Liu, Peng

    2015-12-20

    Endothelial cell damage is an important pathophysiological step of restenosis after angioplasty and stenting. Cell transplantation has great therapeutic potential for endothelial recovery. We investigated the effect of transplanting endothelial progenitor cells (EPCs) derived from human early fetal aortas in rat injured arteries. The carotid arterial endothelium of Sprague-Dawley rats was damaged by dilatation with a 1.5 F balloon catheter, and then EPCs derived from human early fetal aortas (<14 weeks) were injected into the lumen of the injured artery in transplanted rats, with an equal volume of normal saline injected into control rats. Rats were sacrificed at 2 and 4 weeks after treatment and transplanted cells were identified by immunohistochemical staining with anti-human CD31 and anti-human mitochondria antibodies. Arterial cross-sections were analyzed by pathology, immunohistochemistry, and morphometry. Green fluorescence-labeled EPCs could be seen in the endovascular surface of balloon-injured vessels after transplantation. The intimal area and intimal/medial area ratio were significantly smaller in the transplanted group than in the control (P < 0.05) and the residual lumen area was larger (P < 0.05). After EPC transplantation, a complete vascular endothelial layer was formed, which was positive for human von Willebrand factor after immunohistochemical staining, and immunohistochemical staining revealed many CD31- and mitochondria-positive cells in the re-endothelialized endothelium with EPC transplantation but not control treatment. EPCs derived from human early fetal aorta were successfully transplanted into injured vessels and might inhibit neointimal hyperplasia after vascular injury.

  10. A Preliminary Study of the Therapeutic Role of Human Early Fetal Aorta-derived Endothelial Progenitor Cells in Inhibiting Carotid Artery Neointimal Hyperplasia

    PubMed Central

    Xu, Rong-Wei; Zhang, Wen-Jian; Zhang, Jian-Bin; Wen, Jian-Yan; Wang, Meng; Liu, Hong-Lin; Pan, Lin; Yu, Chang-An; Lou, Jin-Ning; Liu, Peng

    2015-01-01

    Background: Endothelial cell damage is an important pathophysiological step of restenosis after angioplasty and stenting. Cell transplantation has great therapeutic potential for endothelial recovery. We investigated the effect of transplanting endothelial progenitor cells (EPCs) derived from human early fetal aortas in rat injured arteries. Methods: The carotid arterial endothelium of Sprague-Dawley rats was damaged by dilatation with a 1.5 F balloon catheter, and then EPCs derived from human early fetal aortas (<14 weeks) were injected into the lumen of the injured artery in transplanted rats, with an equal volume of normal saline injected into control rats. Rats were sacrificed at 2 and 4 weeks after treatment and transplanted cells were identified by immunohistochemical staining with anti-human CD31 and anti-human mitochondria antibodies. Arterial cross-sections were analyzed by pathology, immunohistochemistry, and morphometry. Results: Green fluorescence-labeled EPCs could be seen in the endovascular surface of balloon-injured vessels after transplantation. The intimal area and intimal/medial area ratio were significantly smaller in the transplanted group than in the control (P < 0.05) and the residual lumen area was larger (P < 0.05). After EPC transplantation, a complete vascular endothelial layer was formed, which was positive for human von Willebrand factor after immunohistochemical staining, and immunohistochemical staining revealed many CD31- and mitochondria-positive cells in the re-endothelialized endothelium with EPC transplantation but not control treatment. Conclusion: EPCs derived from human early fetal aorta were successfully transplanted into injured vessels and might inhibit neointimal hyperplasia after vascular injury. PMID:26668152

  11. Brain endothelial miR-146a negatively modulates T-cell adhesion through repressing multiple targets to inhibit NF-κB activation

    PubMed Central

    Wu, Dongsheng; Cerutti, Camilla; Lopez-Ramirez, Miguel A; Pryce, Gareth; King-Robson, Josh; Simpson, Julie E; van der Pol, Susanne MA; Hirst, Mark C; de Vries, Helga E; Sharrack, Basil; Baker, David; Male, David K; Michael, Gregory J; Romero, Ignacio A

    2015-01-01

    Pro-inflammatory cytokine-induced activation of nuclear factor, NF-κB has an important role in leukocyte adhesion to, and subsequent migration across, brain endothelial cells (BECs), which is crucial for the development of neuroinflammatory disorders such as multiple sclerosis (MS). In contrast, microRNA-146a (miR-146a) has emerged as an anti-inflammatory molecule by inhibiting NF-κB activity in various cell types, but its effect in BECs during neuroinflammation remains to be evaluated. Here, we show that miR-146a was upregulated in microvessels of MS-active lesions and the spinal cord of mice with experimental autoimmune encephalomyelitis. In vitro, TNFα and IFNγ treatment of human cerebral microvascular endothelial cells (hCMEC/D3) led to upregulation of miR-146a. Brain endothelial overexpression of miR-146a diminished, whereas knockdown of miR-146a augmented cytokine-stimulated adhesion of T cells to hCMEC/D3 cells, nuclear translocation of NF-κB, and expression of adhesion molecules in hCMEC/D3 cells. Furthermore, brain endothelial miR-146a modulates NF-κB activity upon cytokine activation through targeting two novel signaling transducers, RhoA and nuclear factor of activated T cells 5, as well as molecules previously identified, IL-1 receptor-associated kinase 1, and TNF receptor-associated factor 6. We propose brain endothelial miR-146a as an endogenous NF-κB inhibitor in BECs associated with decreased leukocyte adhesion during neuroinflammation. PMID:25515214

  12. Geniposide inhibited endothelial-mesenchymal transition via the mTOR signaling pathway in a bleomycin-induced scleroderma mouse model

    PubMed Central

    Qi, Qing; Mao, Yueping; Tian, Yongzhen; Zhu, Ke; Cha, Xushan; Wu, Minghua; Zhou, Xiaodong

    2017-01-01

    Aim: Geniposide is an iridoid glycoside isolated from the gardenia plant. It has multiple biological activities. The roles of geniposide in systemic sclerosis (SSc) and in endothelial-to-mesenchymal transition (EndMT) are unclear. We investigated the protective effects of geniposide in a bleomycin-induced SSc mouse model, and its potential mechanisms. Methods: The effects of geniposide were evaluated as follows: (1) histological and immunochemical changes in mouse skin tissue; (2) changes in cellular morphology of human umbilical vein endothelial cells (HUVECs); (3) expression of endothelial cell biomarkers (E-Cadherin, CD31, and CD34), mesenchymal cell markers (FSP1, Collagen, and α-SMA), and key factors of EndMT (Slug, Snail, and Twist) using real time PCR, Western blot, and immunofluorescence; (4) tube formation in HUVECs; (5) mTOR signaling pathway transcription factors using Western blot analysis. Results: Treatment with bleomycin induced up-regulation of mesenchymal cell biomarkers and down-regulation of endothelial cell biomarkers in in vivo and in vitro bleomycin-induced scleroderma models. Geniposide treatment suppressed these effects. Geniposide remedied bleomycin-induced dermal capillary loss and fibrosis in mice. The expression of key EndMT factors (Slug, Snail, and Twist) and the mTOR signaling pathway (mTOR and S6) were also attenuated by geniposide treatment. Conclusion: Geniposide had protective effects on endothelial cells in the bleomycin-induced scleroderma mouse model. These effects may occur via inhibition of the mTOR signaling pathway activation. The results suggested that geniposide could be a potential candidate drug for treatment of vascular damage in SSc patients. PMID:28386330

  13. Genistein inhibits TNF-α-induced endothelial inflammation through the protein kinase pathway A and improves vascular inflammation in C57BL/6 mice.

    PubMed

    Jia, Zhenquan; Babu, Pon Velayutham Anandh; Si, Hongwei; Nallasamy, Palanisamy; Zhu, Hong; Zhen, Wei; Misra, Hara P; Li, Yunbo; Liu, Dongmin

    2013-10-03

    Genistein, a soy isoflavone, has received wide attention for its potential to improve vascular function, but the mechanism of this effect is unclear. Here, we report that genistein at physiological concentrations (0.1 μM-5 μM) significantly inhibited TNF-α-induced adhesion of monocytes to human umbilical vein endothelial cells, a key event in the pathogenesis of atherosclerosis. Genistein also significantly suppressed TNF-α-induced production of adhesion molecules and chemokines such as sICAM-1, sVCAM-1, sE-Selectin, MCP-1 and IL-8, which play key role in the firm adhesion of monocytes to activated endothelial cells (ECs). Genistein at physiologically relevant concentrations didn't significantly induce antioxidant enzyme activities or scavenge free radicals. Further, blocking the estrogen receptors (ERs) in ECs didn't alter the preventive effect of genistein on endothelial inflammation. However, inhibition of protein kinase A (PKA) significantly attenuated the inhibitory effects of genistein on TNF-α-induced monocyte adhesion to ECs as well as the production of MCP-1 and IL-8. In animal study, dietary genistein significantly suppressed TNF-α-induced increase in circulating chemokines and adhesion molecules in C57BL/6 mice. Genistein treatment also reduced VCAM-1 and monocytes-derived F4/80-positive macrophages in the aorta of TNF-α-treated mice. In conclusion, genistein protects against TNF-α-induced vascular endothelial inflammation both in vitro and in vivo models. This anti-inflammatory effect of genistein is independent of the ER-mediated signaling machinery or antioxidant activity, but mediated via the PKA signaling pathway.

  14. Genistein inhibits TNF-α-induced endothelial inflammation through the protein kinase pathway A and improves vascular inflammation in C57BL/6 mice

    PubMed Central

    Jia, Zhenquan; Babu, Pon Velayutham Anandh; Si, Hongwei; Nallasamy, Palanisamy; Zhu, Hong; Zhen, Wei; Misra, Hara P.; Li, Yunbo; Liu, Dongmin

    2013-01-01

    Genistein, a soy isoflavone, has received wide attention for its potential to improve vascular function, but the mechanism of this effect is unclear. Here, we report that genistein at physiological concentrations (0.1 µM–5 µM) significantly inhibited TNF-α-induced adhesion of monocytes to human umbilical vein endothelial cells (HUVECs), a key event in the pathogenesis of atherosclerosis. Genistein also significantly suppressed TNF-α-induced production of adhesion molecules and chemokines such as sICAM-1, sVCAM-1,sE-selectin, MCP-1 and IL-8, which play key role in the firm adhesion of monocytes to activated endothelial cells (ECs). Genistein at physiologically relevant concentrations didn’t significantly induce antioxidant enzyme activities or scavenge free radicals. Further, blocking the estrogen receptors (ERs) in ECs didn’t alter the preventive effect of genistein on endothelial inflammation. However, inhibition of protein kinase A (PKA) significantly attenuated the inhibitory effects of genistein on TNF-α-induced monocyte adhesion to ECs as well as the production of MCP-1 and IL-8. In animal study, dietary genistein (0.1% genistein in the diet) significantly suppressed TNF-α-induced increase in circulating chemokines and adhesion molecules in C57BL/6 mice. Genistein treatment also reduced VCAM-1 and monocytes-derived F4/80-positive macrophages in the aorta of TNF-α treated mice. In conclusion, genistein protects against TNF-α induced vascular endothelial inflammation both in vitro and in vivo models. This anti-inflammatory effect of genistein is independent of the ER-mediated signaling machinery or antioxidant activity, but mediated via the PKA signaling pathway. PMID:23587398

  15. Cyclooxygenase-2 inhibition improves vascular endothelial dysfunction in a rat model of endotoxic shock: role of inducible nitric-oxide synthase and oxidative stress.

    PubMed

    Virdis, Agostino; Colucci, Rocchina; Fornai, Matteo; Blandizzi, Corrado; Duranti, Emiliano; Pinto, Stefania; Bernardini, Nunzia; Segnani, Cristina; Antonioli, Luca; Taddei, Stefano; Salvetti, Antonio; Del Tacca, Mario

    2005-03-01

    We investigated whether cyclooxygenase (COX) isoforms (COX-1 and COX-2) and decreased NO availability contribute to endothelial dysfunction in endotoxemic rats. The involvement of reactive oxygen species (ROS) was also evaluated. Rats were injected with Salmonella-derived lipopolysaccharide or saline. After 6 h, endothelial function of mesenteric resistance arteries was evaluated. In controls, acetylcholine (ACh)-induced relaxation was inhibited by the nitric-oxide synthase inhibitor N(G)-monomethyl-l-arginine (l-NMMA) and unaffected by 5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)-phenyl-2(5H)-furanone (DFU) (COX-2 inhibitor). In lipopolysaccharide (LPS)-treated rats, the response to ACh was blunted compared with controls, less sensitive to l-NMMA, and enhanced by DFU. COX-2 blockade also improved the inhibitory effect of l-NMMA on cholinergic relaxation. SC-560 [5-(4-clorophenyl)-1-(4-metoxyphenyl)-3-trifluoromethylpirazole] (COX-1 inhibitor) did not modify the response to ACh in both groups. LPS-induced endothelial dysfunction was unaffected by the thromboxane A(2) (TxA(2)) receptor antagonist SQ-29548 (7-[3-[[2-[(phenylamino)carbonyl]hydrazino]methyl]-7-oxabicyclo[2.2.1] hept-2-yl]-[1S(1alpha,2alpha(Z),3alpha,4alpha)]-5-heptenoic acid). In vivo inducible nitric-oxide synthase (iNOS) inhibition by S-methylisothiourea partly attenuated LPS-induced endothelial dysfunction. The antioxidants ascorbic acid and superoxide dismutase normalized endothelium-dependent relaxation and restored the inhibitory action of l-NMMA on ACh. Responses to sodium nitroprusside were similar in both groups. In LPS-treated rats, reverse transcription-polymerase chain reaction showed a marked increase in mesenteric iNOS and COX-2 expressions, whereas endothelial nitric-oxide synthase and COX-1 were unchanged. LPS-induced COX-2 overexpression was reduced but not abrogated by S-methylisothiourea. LPS-induced COX-2 up-regulation was also documented by immunohistochemistry. In

  16. EGCG protects endothelial cells against PCB 126-induced inflammation through inhibition of AhR and induction of Nrf2-regulated genes

    SciTech Connect

    Han, Sung Gu; Han, Seong-Su; Toborek, Michal; Hennig, Bernhard

    2012-06-01

    Tea flavonoids such as epigallocatechin gallate (EGCG) protect against vascular diseases such as atherosclerosis via their antioxidant and anti-inflammatory functions. Persistent and widespread environmental pollutants, including polychlorinated biphenyls (PCB), can induce oxidative stress and inflammation in vascular endothelial cells. Even though PCBs are no longer produced, they are still detected in human blood and tissues and thus considered a risk for vascular dysfunction. We hypothesized that EGCG can protect endothelial cells against PCB-induced cell damage via its antioxidant and anti-inflammatory properties. To test this hypothesis, primary vascular endothelial cells were pretreated with EGCG, followed by exposure to the coplanar PCB 126. Exposure to PCB 126 significantly increased cytochrome P450 1A1 (Cyp1A1) mRNA and protein expression and superoxide production, events which were significantly attenuated following pretreatment with EGCG. Similarly, EGCG also reduced DNA binding of NF-κB and downstream expression of inflammatory markers such as monocyte chemotactic protein-1 (MCP-1) and vascular cell adhesion protein-1 (VCAM-1) after PCB exposure. Furthermore, EGCG decreased endogenous or base-line levels of Cyp1A1, MCP-1 and VCAM-1 in endothelial cells. Most of all, treatment of EGCG upregulated expression of NF-E2-related factor 2 (Nrf2)-controlled antioxidant genes, including glutathione S transferase (GST) and NAD(P)H:quinone oxidoreductase 1 (NQO1), in a dose-dependent manner. In contrast, silencing of Nrf2 increased Cyp1A1, MCP-1 and VCAM-1 and decreased GST and NQO1 expression, respectively. These data suggest that EGCG can inhibit AhR regulated genes and induce Nrf2-regulated antioxidant enzymes, thus providing protection against PCB-induced inflammatory responses in endothelial cells. -- Highlights: ► PCBs cause endothelial inflammation and subsequent atherosclerosis. ► Nutrition can modulate toxicity by environmental pollutants. ► We

  17. Anandamide inhibits Theiler's virus induced VCAM-1 in brain endothelial cells and reduces leukocyte transmigration in a model of blood brain barrier by activation of CB1 receptors

    PubMed Central

    2011-01-01

    Background VCAM-1 represents one of the most important adhesion molecule involved in the transmigration of blood leukocytes across the blood-brain barrier (BBB) that is an essential step in the pathogenesis of MS. Several evidences have suggested the potential therapeutic value of cannabinoids (CBs) in the treatment of MS and their experimental models. However, the effects of endocannabinoids on VCAM-1 regulation are poorly understood. In the present study we investigated the effects of anandamide (AEA) in the regulation of VCAM-1 expression induced by Theiler's virus (TMEV) infection of brain endothelial cells using in vitro and in vivo approaches. Methods i) in vitro: VCAM-1 was measured by ELISA in supernatants of brain endothelial cells infected with TMEV and subjected to AEA and/or cannabinoid receptors antagonist treatment. To evaluate the functional effect of VCAM-1 modulation we developed a blood brain barrier model based on a system of astrocytes and brain endothelial cells co-culture. ii) in vivo: CB1 receptor deficient mice (Cnr1-/-) infected with TMEV were treated with the AEA uptake inhibitor UCM-707 for three days. VCAM-1 expression and microglial reactivity were evaluated by immunohistochemistry. Results Anandamide-induced inhibition of VCAM-1 expression in brain endothelial cell cultures was mediated by activation of CB1 receptors. The study of leukocyte transmigration confirmed the functional relevance of VCAM-1 inhibition by AEA. In vivo approaches also showed that the inhibition of AEA uptake reduced the expression of brain VCAM-1 in response to TMEV infection. Although a decreased expression of VCAM-1 by UCM-707 was observed in both, wild type and CB1 receptor deficient mice (Cnr1-/-), the magnitude of VCAM-1 inhibition was significantly higher in the wild type mice. Interestingly, Cnr1-/- mice showed enhanced microglial reactivity and VCAM-1 expression following TMEV infection, indicating that the lack of CB1 receptor exacerbated

  18. Sesamin inhibits macrophage-induced vascular endothelial growth factor and matrix metalloproteinase-9 expression and proangiogenic activity in breast cancer cells.

    PubMed

    Lee, Chun-Chung; Liu, Ko-Jiunn; Wu, Yu-Chen; Lin, Sue-Jane; Chang, Ching-Chun; Huang, Tze-Sing

    2011-06-01

    Sesamin is a sesame component with antihypertensive and antioxidative activities and has recently aroused much interest in studying its potential anticancer application. Macrophage is one of the infiltrating inflammatory cells in solid tumor and may promote tumor progression via enhancement of tumor angiogenesis. In this study, we investigated whether sesamin inhibited macrophage-enhanced proangiogenic activity of breast cancer cell lines MCF-7 and MDA-MB-231. Using vascular endothelial cell capillary tube and network formation assays, both breast cancer cell lines exhibited elevated proangiogenic activities after coculture with macrophages or pretreatment with macrophage-conditioned medium. This elevation of proangiogenic activity was drastically suppressed by sesamin. Vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) induced by macrophages in both cell lines were also inhibited by sesamin. Nuclear levels of HIF-1α and NF-κB, important transcription factors for VEGF and MMP-9 expression, respectively, were obviously reduced by sesamin. VEGF induction by macrophage in MCF-7 cells was shown to be via ERK, JNK, phosphatidylinositol 3-kinase, and NF-κB-mediated pathways. These signaling molecules and additional p38(MAPK) were also involved in macrophage-induced MMP-9 expression. Despite such diverse pathways were induced by macrophage, only Akt and p38(MAPK) activities were potently inhibited by sesamin. Expression of interleukin (IL)-6, IL-8, and tumor necrosis factor-α were substantially increased and involved in macrophage-induced VEGF and MMP-9 mRNA expression in MCF-7 cells. Sesamin effectively inhibited the expression of these cytokines to avoid the reinforced induction of VEGF and MMP-9. In conclusion, sesamin potently inhibited macrophage-enhanced proangiogenic activity of breast cancer cells via inhibition of VEGF and MMP-9 induction.

  19. OSU-A9 inhibits angiogenesis in human umbilical vein endothelial cells via disrupting Akt-NF-κB and MAPK signaling pathways.

    PubMed

    Omar, Hany A; Arafa, El-Shaimaa A; Salama, Samir A; Arab, Hany H; Wu, Chieh-Hsi; Weng, Jing-Ru

    2013-11-01

    Since the introduction of angiogenesis as a useful target for cancer therapy, few agents have been approved for clinical use due to the rapid development of resistance. This problem can be minimized by simultaneous targeting of multiple angiogenesis signaling pathways, a potential strategy in cancer management known as polypharmacology. The current study aimed at exploring the anti-angiogenic activity of OSU-A9, an indole-3-carbinol-derived pleotropic agent that targets mainly Akt-nuclear factor-kappa B (NF-κB) signaling which regulates many key players of angiogenesis such as vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). Human umbilical vein endothelial cells (HUVECs) were used to study the in vitro anti-angiogenic effect of OSU-A9 on several key steps of angiogenesis. Results showed that OSU-A9 effectively inhibited cell proliferation and induced apoptosis and cell cycle arrest in HUVECs. Besides, OSU-A9 inhibited angiogenesis as evidenced by abrogation of migration/invasion and Matrigel tube formation in HUVECs and attenuation of the in vivo neovascularization in the chicken chorioallantoic membrane assay. Mechanistically, Western blot, RT-PCR and ELISA analyses showed the ability of OSU-A9 to inhibit MMP-2 production and VEGF expression induced by hypoxia or phorbol-12-myristyl-13-acetate. Furthermore, dual inhibition of Akt-NF-κB and mitogen-activated protein kinase (MAPK) signaling, the key regulators of angiogenesis, was observed. Together, the current study highlights evidences for the promising anti-angiogenic activity of OSU-A9, at least in part through the inhibition of Akt-NF-κB and MAPK signaling and their consequent inhibition of VEGF and MMP-2. These findings support OSU-A9's clinical promise as a component of anticancer therapy. © 2013.

  20. Adoptive transfer of allogeneic liver sinusoidal endothelial cells specifically inhibits T-cell responses to cognate stimuli.

    PubMed

    Banshodani, Masataka; Onoe, Takashi; Shishida, Masayuki; Tahara, Hiroyuki; Hashimoto, Shinji; Igarashi, Yuka; Tanaka, Yuka; Ohdan, Hideki

    2013-01-01

    Although it is well known that liver allografts are often accepted by recipients, leading to donor-specific tolerance of further organ transplants, the underlying mechanisms remain unclear. We had previously used an in vitro model and showed that mouse liver sinusoidal endothelial cells (LSECs) selectively suppress allospecific T-cells across major histocompatibility complex (MHC) barriers. In the present study, we established an in vivo model for evaluating the immunomodulatory effects of allogeneic LSECs on corresponding T-cells. Allogeneic BALB/cA LSECs were injected intraportally into recombination activating gene 2 γ-chain double-knockout (RAG2/gc-KO, H-2(b)) mice lacking T, B, and natural killer (NK) cells. In order to facilitate LSEC engraftment, the RAG2/gc-KO mice were injected intraperitoneally with monocrotaline 2 days before the adoptive transfer of LSECs; this impaired the host LSECs, conferring a proliferative advantage to the transplanted LSECs. After orthotopic allogeneic LSEC engraftment, the RAG2/gc-KO mice were immune reconstituted intravenously with C57BL/6 splenocytes. After immune reconstitution, mixed lymphocyte reaction (MLR) assay using splenocytes from the recipients revealed that specific inhibition of host CD4(+) and CD8(+) T-cell proliferation was greater in response to allostimulation with irradiated BALB/cA splenocytes rather than to stimulation with irradiated third party SJL/jorllco splenocytes. This inhibitory effect was attenuated by administering anti-programmed death ligand 1 (PD-L1) monoclonal antibody during immune reconstitution in the above-mentioned mice, but not in RAG2/gc-KO mice engrafted with Fas ligand (FasL)-deficient BALB/cA LSECs. Furthermore, engraftment of allogeneic BALB/cA LSECs significantly prolonged the survival of subsequently grafted cognate allogeneic BALB/cA hearts in RAG2/gc-KO mice immune reconstituted with bone marrow transplantation from C57BL/6 mice. In conclusion, murine LSECs have been proven

  1. SIRT4 inhibits cigarette smoke extracts-induced mononuclear cell adhesion to human pulmonary microvascular endothelial cells via regulating NF-κB activity.

    PubMed

    Chen, Yongfeng; Wang, Haijing; Luo, Guangming; Dai, Xiaotian

    2014-05-02

    Cigarette smoking is an important risk factor for chronic obstructive pulmonary disease (COPD), yet its pathogenic mechanisms are not yet fully understood. Endothelial dysfunction is known to be involved in the pathogenesis of COPD. A detailed understanding of the mechanism involved in its progression would have a substantial impact on the optimization and development of treatment strategies. Here, we report that the expression of SIRT4, a mitochondrial sirtuin, is markedly down-regulated in cigarette smoke extract (CSE)-treated human pulmonary microvascular endothelial cells (HPMECs). Overexpression of SIRT4 significantly inhibits CSE-induced mononuclear cell adhesion to HPMECs. Consistently, we found that overexpression of SIRT4 attenuates the induction of vascular cell adhesion molecule 1 (VCAM-1) and E-selectin. Importantly, SIRT4 was found to negatively regulate CSE-induced NF-κB activation via inhibiting the degradation of IκBα. Moreover, we also found that proinflammatory cytokines interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-6, the downstream target genes of NF-κB, are also inhibited by overexpression of SIRT4. These results suggest that SIRT4 protects HPMECs exposed to CSE stress via a mechanism that may involve the NF-κB pathway. Strategies based on the enhancement of SIRT4 may prove to be beneficial in the treatment of cigarette smoking caused COPD. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  2. CCN1 Promotes VEGF Production in Osteoblasts and Induces Endothelial Progenitor Cell Angiogenesis by Inhibiting miR-126 Expression in Rheumatoid Arthritis.

    PubMed

    Chen, Cheng-Yu; Su, Chen-Ming; Hsu, Chin-Jung; Huang, Chien-Chung; Wang, Shih-Wei; Liu, Shih-Chia; Chen, Wei-Cheng; Fuh, Lih-Jyh; Tang, Chih-Hsin

    2017-01-01

    Angiogenesis is the formation of new capillaries from preexisting vasculature. The perpetuation of angiogenesis plays a critical role in the pathogenesis of various disease states including rheumatoid arthritis (RA). Cysteine-rich 61 (Cyr61 or CCN1) is an important proinflammatory cytokine in RA. Here, we investigated the role of CCN1 in angiogenesis associated with vascular endothelial growth factor (VEGF) production and osteoblasts. We found higher expression of CCN1 and VEGF in synovial fluid from RA patients compared with healthy controls. CCN1 induced VEGF expression in osteoblasts and increased endothelial progenitor cells (EPCs) angiogenesis by inhibiting miR-126 via the protein kinase C-alpha (PKC-α) signaling pathway. CCN1 knockdown inhibited angiogenesis in both in vitro and in vivo models. Inhibition of CCN1 expression with lentiviral vectors expressing short hairpin RNA (shRNA) ameliorated articular swelling, cartilage erosion, and angiogenesis in the ankle joint of mice with collagen-induced arthritis (CIA). Our study is the first to describe how CCN1 promotes VEGF expression in osteoblasts and increased EPCs angiogenesis in RA disease. CCN1 may serve as a potential target for RA treatment. © 2016 American Society for Bone and Mineral R