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Sample records for irradiation inhibits vascular

  1. Poly(ADP-ribose) polymerase inhibition reverses vascular dysfunction after gamma-irradiation.

    PubMed

    Beller, Carsten J; Radovits, Tamás; Seres, Leila; Kosse, Jens; Krempien, Robert; Gross, Marie-Luise; Penzel, Roland; Berger, Irina; Huber, Peter E; Hagl, Siegfried; Szabó, Csaba; Szabó, Gábor

    2006-08-01

    The generation of reactive oxygen species during gamma-irradiation may induce DNA damage, leading to activation of the nuclear enzyme poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) culminating in endothelial dysfunction. In the present study, we assessed the effect of PARP inhibition on changes in vascular function after acute and short-term irradiation. In the acute experiments, aortic rings were exposed to 20 Gy of gamma-irradiation. The aortae were harvested after 1 or 7 days. Two additional groups received the ultrapotent PARP inhibitor, INO-1001, for 1 or 7 days after irradiation. The aortic rings were precontracted by phenylephrine and relaxation to acetylcholine and sodium nitroprusside were studied. The vasoconstrictor response to phenylephrine was significantly lower both acutely and 1 and 7 days after irradiation. Vasorelaxation to acetylcholine and sodium nitroprusside was not impaired acutely after irradiation. One and seven days after irradiation, vasorelaxation to acetylcholine and sodium nitroprusside was significantly enhanced. Treatment with INO-1001 reversed vascular dysfunction after irradiation. Vascular dysfunction was observed 1 and 7 days after irradiation, as evidenced by reduced vasoconstriction, coupled with endothelium-dependent and -independent hyperrelaxation. PARP inhibition restored vascular function and may, therefore, be suitable to reverse vascular dysfunction after irradiation.

  2. Very low dose gamma irradiation stimulates gaseous exchange and carboxylation efficiency, but inhibits vascular sap flow in groundnut (Arachis hypogaea L.).

    PubMed

    Ahuja, Sumedha; Singh, Bhupinder; Gupta, Vijay Kumar; Singhal, R K; Venu Babu, P

    2014-02-01

    An experiment was carried out to determine the effect of low dose gamma radiation on germination, plant growth, nitrogen and carbon fixation and carbon flow and release characteristics of groundnut. Dry seeds of groundnut variety Trombay groundnut 37A (TG 37A), a radio mutant type developed by Bhabha Atomic Research Centre (BARC), Mumbai, India, were subjected to the pre-sowing treatment of gamma radiation within low to high dose physiological range, i.e., 0.0, 0.0082, 0.0164. 0.0328, 0.0656, 0.1312, 5, 25, 100, 500 Gray (Gy) from a cobalt source ((60)Co). Observations were recorded for the radiation effect on percentage germination, vigour, gas exchange attributes such as photosynthetic rate, stomatal conductance and transpiration rate, chlorophyll content, root exudation in terms of (14)C release, vascular sap flow rate and activities of rate defining carbon and nitrogen assimilating enzymes such as ribulose-1,5-bisphosphate carboxylase (rubisco) and nitrate reductase (NR). Seed germination was increased by 10-25% at the lower doses up to 5 Gy while the improvement in plant vigour in the same dose range was much higher (22-84%) than the unirradiated control. For radiation exposure above 5 Gy, a dose-dependent decline in germination and plant vigour was measured. No significant effect was observed on the photosynthesis at radiation exposure below 5 Gy but above 5 Gy dose there was a decline in the photosynthetic rate. Stomatal conductance and transpiration rate, however, were only inhibited at a high dose of 500 Gy. Leaf rubisco activity and NR activities remained unaffected at all the investigated doses of gamma irradiation. Mean root exudation and sap flow rate of the irradiated plants, irrespective of the dose, was reduced over the unirradiated control more so in a dose-dependent manner. Results indicated that a very low dose of gamma radiation, in centigray to gray range, did not pose any threat and in fact stimulated metabolic functions in such a way to aid

  3. Epoxygenated Fatty Acids Inhibit Retinal Vascular Inflammation

    PubMed Central

    Capozzi, Megan E.; Hammer, Sandra S.; McCollum, Gary W.; Penn, John S.

    2016-01-01

    The objective of the present study was to assess the effect of elevating epoxygenated fatty acids on retinal vascular inflammation. To stimulate inflammation we utilized TNFα, a potent pro-inflammatory mediator that is elevated in the serum and vitreous of diabetic patients. In TNFα-stimulated primary human retinal microvascular endothelial cells, total levels of epoxyeicosatrienoic acids (EETs), but not epoxydocosapentaenoic acids (EDPs), were significantly decreased. Exogenous addition of 11,12-EET or 19,20-EDP when combined with 12-(3-adamantane-1-yl-ureido)-dodecanoic acid (AUDA), an inhibitor of epoxide hydrolysis, inhibited VCAM-1 and ICAM-1 expression and protein levels; conversely the diol product of 19,20-EDP hydrolysis, 19,20-DHDP, induced VCAM1 and ICAM1 expression. 11,12-EET and 19,20-EDP also inhibited leukocyte adherence to human retinal microvascular endothelial cell monolayers and leukostasis in an acute mouse model of retinal inflammation. Our results indicate that this inhibition may be mediated through an indirect effect on NFκB activation. This is the first study demonstrating a direct comparison of EET and EDP on vascular inflammatory endpoints, and we have confirmed a comparable efficacy from each isomer, suggesting a similar mechanism of action. Taken together, these data establish that epoxygenated fatty acid elevation will inhibit early pathology related to TNFα-induced inflammation in retinal vascular diseases. PMID:27966642

  4. Treatment with pyrophosphate inhibits uremic vascular calcification.

    PubMed

    O'Neill, W Charles; Lomashvili, Koba A; Malluche, Hartmut H; Faugere, Marie-Claude; Riser, Bruce L

    2011-03-01

    Pyrophosphate, which may be deficient in advanced renal failure, is a potent inhibitor of vascular calcification. To explore its use as a potential therapeutic, we injected exogenous pyrophosphate subcutaneously or intraperitoneally in normal rats and found that their plasma pyrophosphate concentrations peaked within 15 min. There was a single exponential decay with a half-life of 33 min. The kinetics were indistinguishable between the two routes of administration or in anephric rats. The effect of daily intraperitoneal pyrophosphate injections on uremic vascular calcification was then tested in rats fed a high-phosphate diet containing adenine for 28 days to induce uremia. Although the incidence of aortic calcification varied and was not altered by pyrophosphate, the calcium content of calcified aortas was significantly reduced by 70%. Studies were repeated in uremic rats given calcitriol to produce more consistent aortic calcification and treated with sodium pyrophosphate delivered intraperitoneally in a larger volume of glucose-containing solution to prolong plasma pyrophosphate levels. This maneuver significantly reduced both the incidence and amount of calcification. Quantitative histomorphometry of bone samples after double-labeling with calcein indicated that there was no effect of pyrophosphate on the rates of bone formation or mineralization. Thus, exogenous pyrophosphate can inhibit uremic vascular calcification without producing adverse effects on bone.

  5. Treatment with pyrophosphate inhibits uremic vascular calcification

    PubMed Central

    O’Neill, W. Charles; Lomashvili, Koba A.; Malluche, Hartmut H.; Faugere, Marie-Claude; Riser, Bruce L.

    2011-01-01

    Pyrophosphate, which may be deficient in advanced renal failure, is a potent inhibitor of vascular calcification. To explore its use as a potential therapeutic, we injected exogenous pyrophosphate subcutaneously or intraperitoneally in normal rats and found that their plasma pyrophosphate concentrations peaked within 15 min. There was a single exponential decay with a half-life of 33 min. The kinetics were indistinguishable between the two routes of administration or in anephric rats. The effect of daily intraperitoneal pyrophosphate injections on uremic vascular calcification was then tested in rats fed a high-phosphate diet containing adenine for 28 days to induce uremia. Although the incidence of aortic calcification varied and was not altered by pyrophosphate, the calcium content of calcified aortas was significantly reduced by 70%. Studies were repeated in uremic rats given calcitriol to produce more consistent aortic calcification and treated with sodium pyrophosphate delivered intraperitoneally in a larger volume of glucose-containing solution to prolong plasma pyrophosphate levels. This maneuver significantly reduced both the incidence and amount of calcification. Quantitative histomorphometry of bone samples after double-labeling with calcein indicated that there was no effect of pyrophosphate on the rates of bone formation or mineralization. Thus, exogenous pyrophosphate can inhibit uremic vascular calcification without producing adverse effects on bone. PMID:21124302

  6. Action spectrum of vascular specific injury using pulsed irradiation

    SciTech Connect

    Tan, O.T.; Murray, S.; Kurban, A.K.

    1989-06-01

    It has been clearly demonstrated that cutaneous blood vessels will be selectively damaged by a laser whose wavelength matches one of the three absorption spectral peaks of the chromophore, oxyhemoglobin, for example, 577 nm. A restriction in the application of this wavelength for the treatment of benign cutaneous vascular tumors, such as portwine stains, has been the penetration depth of 577 nm irradiation of approximately 0.5 mm from the dermal epidermal junction (DEJ). This study was undertaken to establish whether it was possible to increase the penetration depth from 0.5 mm by changing the wavelength to beyond 577 nm in albino pig skin. Results from this study confirm that penetration depth increases from 0.5 to 1.2 mm by changing the wavelength from 577 to 585 nm at 4 J/cm2, while maintaining the same degree of vascular selectivity as that previously described after 577 nm irradiation. This occurred in spite of a mismatch in the wavelength between 585 nm and the oxyhemoglobin absorption peak of 577 nm. Unlike 585 nm irradiation and in contrast with theoretical predictions, 590 nm laser light did not penetrate as deeply as 585 nm. Not only was there a reduction in the penetration depth of the laser beam from 1.2 mm at 585 nm to 0.8 mm at 590 nm, at 4 J/cm2, but there was also a decrease in vascular selectivity in albino pig skin exposed to 590 nm irradiation.

  7. Estrogen inhibits vascular calcification via vascular RANKL system: common mechanism of osteoporosis and vascular calcification.

    PubMed

    Osako, Mariana Kiomy; Nakagami, Hironori; Koibuchi, Nobutaka; Shimizu, Hideo; Nakagami, Futoshi; Koriyama, Hiroshi; Shimamura, Munehisa; Miyake, Takashi; Rakugi, Hiromi; Morishita, Ryuichi

    2010-08-20

    Arterial calcification and osteoporosis are associated in postmenopausal women. RANK (the receptor activator of nuclear factor kappaB), RANKL (RANK ligand), and osteoprotegerin are key proteins in bone metabolism and have been found at the site of aortic calcification. The role of these proteins in vasculature, as well as the contribution of estrogen to vascular calcification, is poorly understood. To clarify the mechanism of RANKL system to vascular calcification in the context of estrogen deficiency. RANKL induced the calcification inducer bone morphogenetic protein-2 by human aortic endothelial cells (HAECs) and decreased the calcification inhibitor matrix Gla protein (MGP) in human aortic smooth muscle cells (HASMCs), as quantified by real-time PCR and Western blot analysis. RANKL also induced bone-related gene mRNA expression and calcium deposition (Alizarin red staining) followed by the osteogenic differentiation of HASMCs. Estrogen inhibited RANKL signaling in HAECs and HASMCs mainly through estrogen receptor alpha. Apolipoprotein E-deficient mice fed with Western high-fat diet for 3 months presented atherosclerotic calcification (Oil red and Alizarin red staining) and osteoporosis (microcomputed tomographic analysis) after ovariectomy and increased expression of RANKL, RANK, and osteopontin in atherosclerotic lesion, as detected by in situ hybridization. Estrogen replacement inhibited osteoporosis and the bone morphogenetic protein osteogenic pathway in aorta by decreasing phosphorylation of smad-1/5/8 and increasing MGP mRNA expression. RANKL contributes to vascular calcification by regulating bone morphogenetic protein-2 and MGP expression, as well as bone-related proteins, and is counteracted by estrogen in a receptor-dependent manner.

  8. Vascular spasm complicates continuous wave but not pulsed laser irradiation

    SciTech Connect

    Gal, D.; Steg, P.G.; Rongione, A.J.; DeJesus, S.T.; Clarke, R.H.; Isner, J.M. )

    1989-11-01

    Preliminary clinical experience with laser angioplasty has suggested that arterial spasm may complicate attempts to employ laser light to accomplish vascular recanalization. The present study was designed to investigate the role of energy profile on the development of arterial spasm during laser angioplasty. Laser irradiation was delivered percutaneously in vivo to New Zealand white rabbits and to Yucatan microswine with or without atherosclerotic lesions induced by a combination of balloon endothelial denudation and atherogenic diet. Continuous wave (CW) laser irradiation from an argon ion gas laser (wavelength 488 to 514 nm) was applied to 23 arteries, while 16 arteries were irradiated using a pulsed xenon chloride (308 nm) or xenon fluoride (351 nm) excimer laser. Arterial spasm, defined as greater than 50% reduction in luminal diameter narrowing, complicated delivery of laser light to 17 (74%) of the 23 arteries irradiated with the CW argon laser. Spasm was consistently observed at powers greater than 2 W, at cumulative exposures greater than 200 seconds, and at total energy greater than 200 joules. Spasm was typically diffuse (including the length of the vessel) and protracted (lasting up to 120 minutes). Intra-arterial nitroglycerin (up to 300 micrograms) produced only temporary and incomplete resolution of laser-induced spasm. In contrast, spasm was never observed in any of the 16 arteries in which laser angioplasty was performed using a pulsed laser (0.95 to 6.37 joules/cm2, 10 to 50 Hz, 48 to 370 seconds). Thus CW but not pulsed laser angioplasty may be complicated by arterial spasm

  9. (-)-DEPRENYL INHIBITS VASCULAR HYPERPERMEABILITY FOLLOWING HEMORRHAGIC SHOCK

    PubMed Central

    J., Binu Tharakan; Whaley, Greg; Hunter, Felicia A.; Smythe, W. Roy; Childs, Ed W.

    2010-01-01

    Recent studies from our laboratory demonstrated the involvement of endothelial cell reactive oxygen species (ROS) formation and activation of apoptotic signaling in vascular hyperpermeability following hemorrhagic shock (HS). The objective of this study was to determine if (-)-deprenyl, an antioxidant with anti-apoptotic properties would attenuate HS-induced vascular hyperpermeability. In rats, HS was induced by withdrawing blood to reduce the MAP to 40 mmHg for 60 minutes followed by resuscitation for 60 minutes. To study hyperpermeability, the rats were injected with FITC-albumin (50 mg/kg) and the changes in integrated optical intensity of the mesenteric post-capillary venules were obtained intra and extra vascularly utilizing intravital microscopy. Mitochondrial ROS formation and mitochondrial transmembrane potential (ΔΨm) were studied using dihydrorhodamine 123 and JC-1 respectively. Mitochondrial release of cytochrome c was determined using ELISA and caspase-3 activity by a fluorometric assay. Parallel studies were performed in rat lung microvascular endothelial cells (RLMEC) utilizing pro-apoptotic BAK as inducer of hyperpermeability. Hemorrhagic shock induced vascular hyperpermeability, mitochondrial ROS formation, decrease in ΔΨm, release of cytochrome c and caspase-3 activation (p < 0.05). (-)-Deprenyl (0.15 mg/Kg) attenuated all these effects (p < 0.05). Similarly in RLMEC, (-)-deprenyl attenuated BAK peptide induced monolayer hyperpermeability (p < 0.05), ROS formation, decrease in ΔΨm, cytochrome c release (p < 0.05) and activation of caspase-3 (p < 0.05). The protective effects of (-)-deprenyl on vascular barrier functions may be due to its protective effects on ΔΨm thereby preventing mitochondrial release of cytochrome c and caspase-3 mediated disruption of endothelial adherens junctions. PMID:19373132

  10. Loss of vascular fibrinolytic activity following irradiation of the liver - an aspect of late radiation damage

    SciTech Connect

    Henderson, B.W.; Bicher, H.I.; Johnson, R.J.

    1983-09-01

    The vascular fibrinolytic activity, known to originate from the endothelium, was studied histochemically by fibrinolysis autography in liver samples from beagles exposed to radiation treatment. Eighteen to thirty months prior to sacrifice, six dogs received x irradiation (4600 rad in 5 weeks) and three dogs received x irradiation plus aspirin (1 g/kg). Two dogs served as untreated controls. Control livers showed extensive fibrinolytic activity related to large and small vascular structures. The vascular fibrinolytic activity had been lost from all vessels except the major portal branches in five irradiated livers and was severaly diminished in three. One irradiated liver appeared to possess normal fibrinolytic activity.

  11. Tumor Vascular Changes Mediated by Inhibition of Oncogenic Signaling

    PubMed Central

    Qayum, Naseer; Muschel, Ruth J.; Im, Jae Hong; Balathasan, Lukxmi; Koch, Cameron J.; Patel, Sonal; McKenna, W. Gillies; Bernhard, Eric J.

    2009-01-01

    Many inhibitors of the EGFR-RAS-PI3 kinase-AKT signaling pathway are in clinical use or under development for cancer therapy. Here we show that treatment of mice bearing human tumor xenografts with inhibitors that block EGFR, RAS, PI3 kinase or AKT resulted in prolonged and durable enhancement of tumor vascular flow, perfusion and decreased tumor hypoxia. The vessels in the treated tumors had decreased tortuosity and increased internodal length accounting for the functional alterations. Inhibition of tumor growth cannot account for these results as the drugs were given at doses that did not alter tumor growth. The tumor cell itself was an essential target as HT1080 tumors that lack EGFR did not respond to an EGFR inhibitor, but did respond with vascular alterations to RAS or PI3 Kinase inhibition. We extended these observations to spontaneously arising tumors in MMTV-neu mice. These tumors also responded to PI3 kinase inhibition with decreased tumor hypoxia, increased vascular flow and morphological alterations of their vessels including increased vascular maturity and acquisition of pericyte markers. These changes are similar to the vascular normalization that has been described after anti-angiogenic treatment of xenografts. One difficulty in the use of vascular normalization as a therapeutic strategy has been its limited duration. In contrast, blocking tumor cell RAS-PI3K-AKT signaling led to persistent vascular changes that might be incorporated into clinical strategies based on improvement of vascular flow or decreased hypoxia. These results indicate that vascular alterations must be considered as a consequence of signaling inhibition in cancer therapy. PMID:19622766

  12. Relaxin inhibits early steps in vascular inflammation.

    PubMed

    Brecht, Anna; Bartsch, Cornelia; Baumann, Gert; Stangl, Karl; Dschietzig, Thomas

    2011-01-17

    Increased expression of endothelial adhesion molecules, high levels of the monocyte chemoattractant protein-1 (MCP-1) and enhanced VLA4 integrin/VCAM-1 and CCR-2/MCP-1 interactions are initial steps in vascular inflammation. We sought to determine whether relaxin, a potent vasodilatory and anti-fibrotic agent, mitigates these early events compromising endothelial integrity. The effect of relaxin coincubation on the TNF-α-stimulated expression of the adhesion molecules VCAM-1, ICAM-1 and E-selectin; the MCP-1 expression by human umbilical vein endothelial cells (HUVEC) and human aortic smooth muscle cells (HAoSMC); as well as on direct monocyte-endothelium cell adhesion was quantified by ELISA or adhesion assay. CCR-2 and PECAM expression on HUVEC and THP-1 monocytes was investigated by FACS analysis. Relaxin treatment suppressed significantly TNF-α-induced upregulation of VCAM-1 and PECAM, CCR-2, and MCP-1 levels and direct monocyte adhesion to HUVEC. Our findings identify relaxin as a promising inhibitory factor in early vascular inflammation. By attenuating the upregulation of VCAM-1, key adhesion molecule in early vascular inflammation, and of MCP-1, a chemokine pivotal to monocyte recruitment, relaxin decreased initial monocyte-endothelium contact. This may be of relevance for the prevention and treatment of atherosclerosis and of other pro-inflammatory states.

  13. Abrogation of Early Apoptosis Does Not Alter Late Inhibition of Hippocampal Neurogenesis After Irradiation

    SciTech Connect

    Li Yuqing; Aubert, Isabelle; Wong, C. Shun

    2010-07-15

    Purpose: Irradiation of the adult brain results in acute apoptosis of neural progenitors and vascular endothelial cells, as well as late dysfunction of neural progenitors and inhibition of neurogenesis. We sought to determine whether the early apoptotic response has a causative role in late inhibition of neurogenesis after cranial irradiation. Methods and Materials: Using a genetic approach with p53 and smpd1 transgenic mice and a pharmacologic approach with basic fibroblast growth factor (bFGF) to abrogate the early apoptotic response, we evaluated the late inhibition of neurogenesis in the hippocampal dentate gyrus after cranial irradiation. Results: In dentate gyrus, subgranular neural progenitors underwent p53-dependent apoptosis within 24 h after irradiation. Despite a near abrogation of neural progenitor apoptosis in p53-/- mice, the reduction in newborn neurons in dentate gyrus at 9 weeks after irradiation in p53-/- mice was not different from that observed in wildtype controls. Endothelial cell apoptosis after radiation is mediated by membrane damage initiated by activation of acid sphingomyelinase (ASMase). Deletion of the smpd1 gene (which encodes ASMase) attenuated the apoptotic response of endothelial cells. At 9 weeks after irradiation, the inhibition of hippocampal neurogenesis was not rescued by ASMase deficiency. Intravenous administration of bFGF protected both endothelial cells and neural progenitors against radiation-induced apoptosis. There was no protection against inhibition of neurogenesis at 9 weeks after irradiation in bFGF-treated mice. Conclusion: Early apoptotic death of neural progenitors, endothelial cells, or both does not have a causative association with late inhibition of neurogenesis after irradiation.

  14. Cysteamine prevents vascular leakage through inhibiting transglutaminase in diabetic retina.

    PubMed

    Lee, Yeon-Ju; Jung, Se-Hui; Hwang, JongYun; Jeon, Sohee; Han, Eun-Taek; Park, Won Sun; Hong, Seok-Ho; Kim, Young-Myeong; Ha, Kwon-Soo

    2017-10-01

    Cysteamine (an aminothiol), which is derived from coenzyme A degradation and metabolized into taurine, has beneficial effects against cystinosis and neurodegenerative diseases; however, its role in diabetic complications is unknown. Thus, we sought to determine the preventive effect of cysteamine against hyperglycemia-induced vascular leakage in the retinas of diabetic mice. Cysteamine and ethanolamine, the sulfhydryl group-free cysteamine analogue, inhibited vascular endothelial growth factor (VEGF)-induced stress fiber formation and vascular endothelial (VE)-cadherin disruption in endothelial cells, which play a critical role in modulating endothelial permeability. Intravitreal injection of the amine compounds prevented hyperglycemia-induced vascular leakage in the retinas of streptozotocin-induced diabetic mice. We then investigated the potential roles of reactive oxygen species (ROS) and transglutaminase (TGase) in the cysteamine prevention of VEGF-induced vascular leakage. Cysteamine, but not ethanolamine, inhibited VEGF-induced ROS generation in endothelial cells and diabetic retinas. In contrast, VEGF-induced TGase activation was prevented by both cysteamine and ethanolamine. Our findings suggest that cysteamine protects against vascular leakage through inhibiting VEGF-induced TGase activation rather than ROS generation in diabetic retinas. © 2017 Society for Endocrinology.

  15. Anticancer therapy-induced vascular toxicity: VEGF inhibition and beyond.

    PubMed

    Di Lisi, Daniela; Madonna, Rosalinda; Zito, Concetta; Bronte, Enrico; Badalamenti, Giuseppe; Parrella, Paolo; Monte, Ines; Tocchetti, Carlo Gabriele; Russo, Antonio; Novo, Giuseppina

    2017-01-15

    Cardiotoxicity induced by chemotherapeutic agents and radiotherapy is a growing problem. In recent years, an increasing number of new drugs with targeted action have been designed. These molecules, such as monoclonal antibodies and tyrosine kinase inhibitors, can cause different type of toxicities compared to traditional chemotherapy. However, they can also cause cardiac complications such as heart failure, arterial hypertension, QT interval prolongation and arrhythmias. Currently, a field of intense research is the vascular toxicity induced by new biologic drugs, particularly those which inhibit vascular endothelial growth factor (VEGF) and its receptor (VEGF-R) and other tyrosine kinases. In this review, we aim at focusing on the problem of vascular toxicity induced by new targeted therapies, chemotherapy and radiotherapy, and describe the main mechanisms and emphasizing the importance of early diagnosis of vascular damage, in order to prevent clinical complications.

  16. Oligogalacturonic Acid Inhibits Vascular Calcification by Two Mechanisms: Inhibition of Vascular Smooth Muscle Cell Osteogenic Conversion and Interaction With Collagen.

    PubMed

    Hodroge, Ahmed; Trécherel, Eric; Cornu, Marjorie; Darwiche, Walaa; Mansour, Ali; Ait-Mohand, Katia; Verissimo, Thomas; Gomila, Cathy; Schembri, Carole; Da Nascimento, Sophie; Elboutachfaiti, Redouan; Boullier, Agnès; Lorne, Emmanuel; Courtois, Josiane; Petit, Emmanuel; Toumieux, Sylvestre; Kovensky, José; Sonnet, Pascal; Massy, Ziad A; Kamel, Saïd; Rossi, Claire; Ausseil, Jérôme

    2017-07-01

    Cardiovascular diseases constitute the leading cause of mortality worldwide. Calcification of the vessel wall is associated with cardiovascular morbidity and mortality in patients having many diseases, including diabetes mellitus, atherosclerosis, and chronic kidney disease. Vascular calcification is actively regulated by inductive and inhibitory mechanisms (including vascular smooth muscle cell adaptation) and results from an active osteogenic process. During the calcification process, extracellular vesicles (also known as matrix vesicles) released by vascular smooth muscle cells interact with type I collagen and then act as nucleating foci for calcium crystallization. Our primary objective was to identify new, natural molecules that inhibit the vascular calcification process. We have found that oligogalacturonic acids (obtained by the acid hydrolysis of polygalacturonic acid) reduce in vitro inorganic phosphate-induced calcification of vascular smooth muscle cells by 80% and inorganic phosphate-induced calcification of isolated rat aortic rings by 50%. A specific oligogalacturonic acid with a degree of polymerization of 8 (DP8) was found to inhibit the expression of osteogenic markers and, thus, prevent the conversion of vascular smooth muscle cells into osteoblast-like cells. We also evidenced in biochemical and immunofluorescence assays a direct interaction between matrix vesicles and type I collagen via the GFOGER sequence (where single letter amino acid nomenclature is used, O=hydroxyproline) thought to be involved in interactions with several pairs of integrins. DP8 inhibits vascular calcification development mainly by inhibition of osteogenic marker expression but also partly by masking the GFOGER sequence-thereby, preventing matrix vesicles from binding to type I collagen. © 2017 American Heart Association, Inc.

  17. 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.

  18. Sphingosylphosphorylcholine inhibits macrophage adhesion to vascular smooth muscle cells.

    PubMed

    Wirrig, Christiane; McKean, Jenny S; Wilson, Heather M; Nixon, Graeme F

    2016-09-01

    Inflammation in de-endothelialised arteries contributes to the development of cardiovascular diseases. The process that initiates this inflammatory response is the adhesion of monocytes/macrophages to exposed vascular smooth muscle cells, typically stimulated by cytokines such as tumour necrosis factor-α (TNF). The aim of this study was to determine the effect of the sphingolipid sphingosylphosphorylcholine (SPC) on the interaction of monocytes/macrophages with vascular smooth muscle cells. Rat aortic smooth muscle cells and rat bone marrow-derived macrophages were co-cultured using an in vitro assay following incubation with sphingolipids to assess inter-cellular adhesion. We reveal that SPC inhibits the TNF-induced adhesion of macrophages to smooth muscle cells. This anti-adhesive effect was the result of SPC-induced changes to the smooth muscle cells (but not the macrophages) and was mediated, at least partly, via the sphingosine 1-phosphate receptor subtype 2. Lipid raft domains were also required. Although SPC did not alter expression or membrane distribution of the adhesion proteins intercellular adhesion molecule-1 and vascular cellular adhesion protein-1 in smooth muscle cells, SPC preincubation inhibited the TNF-induced increase in inducible nitric oxide synthase (NOS2) resulting in a subsequent decrease in nitric oxide production. Inhibiting NOS2 activation in smooth muscle cells led to a decrease in the adhesion of macrophages to smooth muscle cells. This study has therefore delineated a novel pathway which can inhibit the interaction between macrophages and vascular smooth muscle cells via SPC-induced repression of NOS2 expression. This mechanism could represent a potential drug target in vascular disease. Copyright © 2016. Published by Elsevier Inc.

  19. Thalidomide Ameliorates Inflammation and Vascular Injury but Aggravates Tubular Damage in the Irradiated Mouse Kidney

    SciTech Connect

    Scharpfenecker, Marion; Floot, Ben; Russell, Nicola S.; Coppes, Rob P.; Stewart, Fiona A.

    2014-07-01

    Purpose: The late side effects of kidney irradiation include vascular damage and fibrosis, which are promoted by an irradiation-induced inflammatory response. We therefore treated kidney-irradiated mice with the anti-inflammatory and angiogenesis-modulating drug thalidomide in an attempt to prevent the development of late normal tissue damage and radiation nephropathy in the mouse kidney. Methods and Materials: Kidneys of C57Bl/6 mice were irradiated with a single dose of 14 Gy. Starting from week 16 after irradiation, the mice were fed with thalidomide-containing chow (100 mg/kg body weight/day). Gene expression and kidney histology were analyzed at 40 weeks and blood samples at 10, 20, 30, and 40 weeks after irradiation. Results: Thalidomide improved the vascular structure and vessel perfusion after irradiation, associated with a normalization of pericyte coverage. The drug also reduced infiltration of inflammatory cells but could not suppress the development of fibrosis. Irradiation-induced changes in hematocrit and blood urea nitrogen levels were not rescued by thalidomide. Moreover, thalidomide worsened tubular damage after irradiation and also negatively affected basal tubular function. Conclusions: Thalidomide improved the inflammatory and vascular side effects of kidney irradiation but could not reverse tubular toxicity, which probably prevented preservation of kidney function.

  20. Cardamonin inhibits agonist-induced vascular contractility via Rho-kinase and MEK inhibition.

    PubMed

    Je, Hyun Dong; Jeong, Ji Hoon

    2016-01-01

    The present study was undertaken to investigate the influence of cardamonin on vascular smooth muscle contractility and to determine the mechanism(s) involved. Denuded aortic rings from male rats were used and isometric contractions were recorded and combined with molecular experiments. Cardamonin significantly relaxed fluoride-, phenylephrine-, and phorbol ester-induced vascular contractions, suggesting that it has an anti-hypertensive effect on agonist-induced vascular contraction regardless of endothelial nitric oxide synthesis. Furthermore, cardamonin significantly inhibited the fluoride-induced increase in pMYPT1 level and phenylephrine-induced increase in pERK1/2 level, suggesting inhibition of Rho-kinase and MEK activity and subsequent phosphorylation of MYPT1 and ERK1/2. This study provides evidence that the relaxing effect of cardamonin on agonist-induced vascular contraction regardless of endothelial function involves inhibition of Rho-kinase and MEK activity.

  1. Adrenal Androgen Dehydroepiandrosterone Sulfate Inhibits Vascular Remodeling Following Arterial Injury

    PubMed Central

    Ii, Masaaki; Hoshiga, Masaaki; Negoro, Nobuyuki; Fukui, Ryosuke; Nakakoji, Takahiro; Kohbayashi, Eiko; Shibata, Nobuhiko; Furutama, Daisuke; Ishihara, Tadashi; Hanafusa, Toshiaki; Losordo, Douglas W.; Ohsawa, Nakaaki

    2009-01-01

    Recent epidemiologic studies have suggested that serum dehydroepiandrosterone sulfate (DHEAS) levels have a significant inverse correlation with the incidence of cardiovascular diseases. However, direct evidence for the association with DHEAS and vascular disorders has not yet been explored. DHEAS significantly reduced neointima formation 28 days after surgery without altering other serum metabolite levels in a rabbit carotid balloon injury model. Immunohistochemical analyses revealed the reduction of proliferating cell nuclear antigen (PCNA) index and increase of TdT-mediated dUTP-biotin Nick End Labeling (TUNEL) index, expressing differentiated vascular smooth muscle cell (VSMC) markers in the media 7 days after surgery. In vitro, DHEAS exhibited inhibitory effects on VSMC proliferation and migration activities, inducing G1 cell cycle arrest with upregulation of one of the cyclin dependent kinase (CDK) inhibitors p16INK4a and apoptosis with activating peroxisome proliferator-activated receptor (PPAR)-α in VSMCs. DHEAS inhibits vascular remodeling reducing neointima formation after vascular injury via its effects on VSMC phenotypic modulation, functions and apoptosis upregulating p16INK4a/activating PPARα. DHEAS may play a pathophysiological role for vascular remodeling in cardiovascular disease. PMID:19298964

  2. Effects of low-intensity laser irradiation on the apoptosis of rabbit vascular smooth muscle cells in culture

    NASA Astrophysics Data System (ADS)

    Li, S. D.; Chen, P.; Zhang, C. P.; Wen, J. X.; Liang, J.; Kang, H. X.; Gao, R. L.; Fu, X. B.

    2011-11-01

    Restenosis is a major complication after coronary intervention therapy. Excessive proliferation of vascular smooth muscle cells (VSMCs) and a decline in their apoptosis, which eventually leads to excessive neointimal thickening in coronary arteries, are the main causes of restenosis. Induction of the apoptosis of VSMCs and inhibition of excessive proliferation of VSMCs are therefore crucial for the prevention of restenosis, and low-intensity laser irradiation of coronary arteries may play a promising role in keeping this in balance. In this study, we used in vitro cultured rabbit VSMCs to investigate the effects of low-intensity laser irradiation at a wavelength of 532 nm on the apoptosis of VSMCs via morphological observation and molecular biology. The results showed that apoptotic bodies and obvious intranuclear apoptosis-positive particles formed within VSMCs 24 h after laser irradiation, suggesting that low-intensity laser irradiation at certain doses can inhibit the proliferation of VSMCs by promoting their apoptosis. This experiment provides evidences for further animal experiments and clinical trials on prevention and treatment of restenosis by intracoronary low-intensity laser irradiation at a wavelength of 532 nm.

  3. Atorvastatin inhibits myocardin expression in vascular smooth muscle cells.

    PubMed

    Li, Jingjing; Jiang, Jixin; Yin, Hao; Wang, Lifeng; Tian, Ruijuan; Li, Haijie; Wang, Zengyong; Li, Dong; Wang, Yuebing; Gui, Yu; Walsh, Michael P; Zheng, Xi-Long

    2012-07-01

    Atorvastatin (ATV), an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, is widely prescribed as a lipid-lowering drug. It also inhibits the RhoA-Rho-associated kinase pathway in vascular smooth muscle (SM) cells and critically inhibits SM function. Myocardin is a coactivator of serum response factor, which upregulates SM contractile proteins. The RhoA-Rho-associated kinase pathway, which directly triggers SM contraction, also increases myocardin gene expression. Therefore, we investigated whether ATV inhibits myocardin gene expression in SM cells. In mice injected with ATV (IP 20 μg/g per day) for 5 days, myocardin gene expression was significantly downregulated in aortic and carotid arterial tissues with decreased expression of myocardin target genes SM α-actin and SM22. Correspondingly, the contractility of aortic rings in mice treated with ATV or the Rho-associated kinase inhibitor Y-27632 was reduced in response to treatment with either KCl or phenylephrine. In cultured mouse and human aortic SM cells, KCl treatment stimulated the expression of myocardin, SM α-actin, and SM22. These stimulatory effects were prevented by ATV treatment. ATV-induced inhibition of myocardin expression was prevented by pretreatment with either mevalonate or geranylgeranylpyrophosphate but not farnesylpyrophosphate. Treatment with Y-27632 mimicked ATV effects on the gene expression of myocardin, SM α-actin, and SM22, further suggesting a role for the RhoA-Rho-associated kinase pathway in ATV effects. Furthermore, ATV treatment inhibited RhoA membrane translocation and activation; these effects were prevented by pretreatment with mevalonate. We conclude that ATV inhibits myocardin gene expression in vivo and in vitro, suggesting a novel mechanism for ATV inhibition of vascular contraction.

  4. T Lymphocytes Inhibit the Vascular Response to Injury

    NASA Astrophysics Data System (ADS)

    Hansson, Goran K.; Holm, Jan; Holm, Susanna; Fotev, Zisi; Hedrich, Hans-Jurgen; Fingerle, Jurgen

    1991-12-01

    The proliferation of vascular smooth muscle cells is controlled by specific growth factors and cytokines acting in paracrine networks. Macrophage products such as the platelet-derived growth factor and interleukin 1 promote smooth muscle proliferation and are released in the arterial wall during atherosclerosis and repair processes. T lymphocytes are also present in vascular tissue, but their role in vascular growth control in vivo has been unclear. We now demonstrate that rats in which T lymphocytes have been eliminated by a monoclonal antibody develop larger proliferative arterial lesions after balloon-catheter injury. Larger lesions also develop in athymic rnu/rnu rats that lack T lymphocytes, when compared with rnu/+ littermates with normal T-cell levels. Finally, injection of the lymphokine interferon γ inhibits smooth muscle proliferation and results in smaller lesions compared with controls injected with buffer alone. These results indicate that T lymphocytes modulate smooth muscle proliferation during vascular repair. We propose that T lymphocytes may play an important, immunologically nonspecific role in tissue repair processes.

  5. Vinpocetine Suppresses Pathological Vascular Remodeling by Inhibiting Vascular Smooth Muscle Cell Proliferation and Migration

    PubMed Central

    Cai, Yujun; Knight, Walter E.; Guo, Shujie; Li, Jian-Dong; Knight, Peter A.

    2012-01-01

    Abnormal vascular smooth muscle cell (SMC) activation is associated with various vascular disorders such as atherosclerosis, in-stent restenosis, vein graft disease, and transplantation-associated vasculopathy. Vinpocetine, a derivative of the alkaloid vincamine, has long been used as a cerebral blood flow enhancer for treating cognitive impairment. However, its role in pathological vascular remodeling remains unexplored. Herein, we show that systemic administration of vinpocetine significantly reduced neointimal formation in carotid arteries after ligation injury. Vinpocetine also markedly decreased spontaneous remodeling of human saphenous vein explants in ex vivo culture. In cultured SMCs, vinpocetine dose-dependently suppressed cell proliferation and caused G1-phase cell cycle arrest, which is associated with a decrease in cyclin D1 and an increase in p27Kip1 levels. In addition, vinpocetine dose-dependently inhibited platelet-derived growth factor (PDGF)-stimulated SMC migration as determined by the two-dimensional migration assays and three-dimensional aortic medial explant invasive assay. Moreover, vinpocetine significantly reduced PDGF-induced type I collagen and fibronectin expression. It is noteworthy that PDGF-stimulated phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2), but not protein kinase B, was specifically inhibited by vinpocetine. Vinpocetine powerfully attenuated intracellular reactive oxidative species (ROS) production, which largely mediates the inhibitory effects of vinpocetine on ERK1/2 activation and SMC growth. Taken together, our results reveal a novel function of vinpocetine in attenuating neointimal hyperplasia and pathological vascular remodeling, at least partially through suppressing ROS production and ERK1/2 activation in SMCs. Given the safety profile of vinpocetine, this study provides insight into the therapeutic potential of vinpocetine in proliferative vascular disorders. PMID:22915768

  6. Ultrasound triggered image-guided drug delivery to inhibit vascular reconstruction via paclitaxel-loaded microbubbles.

    PubMed

    Zhu, Xu; Guo, Jun; He, Cancan; Geng, Huaxiao; Yu, Gengsheng; Li, Jinqing; Zheng, Hairong; Ji, Xiaojuan; Yan, Fei

    2016-02-22

    Paclitaxel (PTX) has been recognized as a promising drug for intervention of vascular reconstructions. However, it is still difficult to achieve local drug delivery in a spatio-temporally controllable manner under real-time image guidance. Here, we introduce an ultrasound (US) triggered image-guided drug delivery approach to inhibit vascular reconstruction via paclitaxel (PTX)-loaded microbubbles (PLM) in a rabbit iliac balloon injury model. PLM was prepared through encapsulating PTX in the shell of lipid microbubbles via film hydration and mechanical vibration technique. Our results showed PLM could effectively deliver PTX when exposed to US irradiation and result in significantly lower viability of vascular smooth muscle cells. Ultrasonographic examinations revealed the US signals from PLM in the iliac artery were greatly increased after intravenous administration of PLM, making it possible to identify the restenosis regions of iliac artery. The in vivo anti-restenosis experiments with PLM and US greatly inhibited neointimal hyperplasia at the injured site, showing an increased lumen area and reduced the ratio of intima area and the media area (I/M ratio). No obvious functional damages to liver and kidney were observed for those animals. Our study provided a promising approach to realize US triggered image-guided PTX delivery for therapeutic applications against iliac restenosis.

  7. Ultrasound triggered image-guided drug delivery to inhibit vascular reconstruction via paclitaxel-loaded microbubbles

    PubMed Central

    Zhu, Xu; Guo, Jun; He, Cancan; Geng, Huaxiao; Yu, Gengsheng; Li, Jinqing; Zheng, Hairong; Ji, Xiaojuan; Yan, Fei

    2016-01-01

    Paclitaxel (PTX) has been recognized as a promising drug for intervention of vascular reconstructions. However, it is still difficult to achieve local drug delivery in a spatio-temporally controllable manner under real-time image guidance. Here, we introduce an ultrasound (US) triggered image-guided drug delivery approach to inhibit vascular reconstruction via paclitaxel (PTX)-loaded microbubbles (PLM) in a rabbit iliac balloon injury model. PLM was prepared through encapsulating PTX in the shell of lipid microbubbles via film hydration and mechanical vibration technique. Our results showed PLM could effectively deliver PTX when exposed to US irradiation and result in significantly lower viability of vascular smooth muscle cells. Ultrasonographic examinations revealed the US signals from PLM in the iliac artery were greatly increased after intravenous administration of PLM, making it possible to identify the restenosis regions of iliac artery. The in vivo anti-restenosis experiments with PLM and US greatly inhibited neointimal hyperplasia at the injured site, showing an increased lumen area and reduced the ratio of intima area and the media area (I/M ratio). No obvious functional damages to liver and kidney were observed for those animals. Our study provided a promising approach to realize US triggered image-guided PTX delivery for therapeutic applications against iliac restenosis. PMID:26899550

  8. A ketolide antibiotic, telithromycin, inhibits vascular adrenergic neurotransmission in the rat mesenteric vascular bed

    PubMed Central

    Hatanaka, Y; Zamami, Y; Koyama, T; Hobara, N; Jin, X; Kitamura, Y; Kawasaki, H

    2008-01-01

    Background and purpose: A ketolide antibiotic, telithromycin, has side effects including temporary loss of consciousness in clinical use, but the underlying mechanisms remain unclear. This study investigated the effects of telithromycin on perivascular nerve function in rat mesenteric arteries, in comparison with those of macrolide (erythromycin and clarithromycin) and new quinolone antibiotics (levofloxacin and gatifloxacin). Experimental approach: In vitro, vascular responses and release of noradrenaline induced by periarterial nerve stimulation (PNS) of rat perfused mesenteric vascular beds were measured in the presence of each antibiotic. In vivo blood pressure measurement was performed in Wistar rats. Key results: In mesenteric preparations with resting tone, telithromycin (10 nM–10 μM) markedly inhibited PNS (4–12 Hz)-induced adrenergic nerve- and exogenous noradrenaline-mediated vasoconstriction, whereas the other antibiotics slightly inhibited PNS-induced responses without affecting noradrenaline-induced responses. Telithromycin significantly reduced PNS (12 Hz)-evoked noradrenaline release in the perfusate. In pre-constricted preparations with or without endothelium, telithromycin (0.1 nM–10 μM) caused a concentration-dependent vasodilation. Telithromycin (10 nM) inhibited calcium-induced vasoconstriction in high KCl and calcium-free medium. None of the antibiotics used affected PNS (0.5–2 Hz)-induced calcitonin gene-related peptide (CGRP) nerve- and exogenous CGRP-mediated vasodilation. Intravenous injection of telithromycin significantly lowered blood pressure in anaesthetized rats. Conclusions and implications: These results suggest that telithromycin causes not only strong inhibition of perivascular adrenergic neurotransmission but also a vasodilator action in mesenteric vascular beds and hypotension. It is thus possible that telithromycin increases visceral blood flow, consequently reducing cerebral blood flow and resulting

  9. Synchrotron microbeam irradiation induces neutrophil infiltration, thrombocyte attachment and selective vascular damage in vivo

    PubMed Central

    Brönnimann, Daniel; Bouchet, Audrey; Schneider, Christoph; Potez, Marine; Serduc, Raphaël; Bräuer-Krisch, Elke; Graber, Werner; von Gunten, Stephan; Laissue, Jean Albert; Djonov, Valentin

    2016-01-01

    Our goal was the visualizing the vascular damage and acute inflammatory response to micro- and minibeam irradiation in vivo. Microbeam (MRT) and minibeam radiation therapies (MBRT) are tumor treatment approaches of potential clinical relevance, both consisting of parallel X-ray beams and allowing the delivery of thousands of Grays within tumors. We compared the effects of microbeams (25–100 μm wide) and minibeams (200–800 μm wide) on vasculature, inflammation and surrounding tissue changes during zebrafish caudal fin regeneration in vivo. Microbeam irradiation triggered an acute inflammatory response restricted to the regenerating tissue. Six hours post irradiation (6 hpi), it was infiltrated by neutrophils and fli1a+ thrombocytes adhered to the cell wall locally in the beam path. The mature tissue was not affected by microbeam irradiation. In contrast, minibeam irradiation efficiently damaged the immature tissue at 6 hpi and damaged both the mature and immature tissue at 48 hpi. We demonstrate that vascular damage, inflammatory processes and cellular toxicity depend on the beam width and the stage of tissue maturation. Minibeam irradiation did not differentiate between mature and immature tissue. In contrast, all irradiation-induced effects of the microbeams were restricted to the rapidly growing immature tissue, indicating that microbeam irradiation could be a promising tumor treatment tool. PMID:27640676

  10. Vascular Injury After Whole Thoracic X-Ray Irradiation in the Rat

    SciTech Connect

    Ghosh, S.N. Wu, Q. M.S.; Maeder, M.; Fish, B.L.; Moulder, J.E.; Jacobs, E.R.; Medhora, M.; Molthen, R.C.

    2009-05-01

    Purpose: To study vascular injury after whole thoracic irradiation with single sublethal doses of X-rays in the rat and to develop markers that might predict the severity of injury. Methods and Materials: Rats that received 5- or 10-Gy thorax-only irradiation and age-matched controls were studied at 3 days, 2 weeks, and 1, 2, 5, and 12 months. Several pulmonary vascular parameters were evaluated, including hemodynamics, vessel density, total lung angiotensin-converting enzyme activity, and right ventricular hypertrophy. Results: By 1 month, the rats in the 10-Gy group had pulmonary vascular dropout, right ventricular hypertrophy, increased pulmonary vascular resistance, increased dry lung weights, and decreases in total lung angiotensin-converting enzyme activity, as well as pulmonary artery distensibility. In contrast, irradiation with 5 Gy resulted in only a modest increase in right ventricular weight and a reduction in lung angiotensin-converting enzyme activity. Conclusion: In a previous investigation using the same model, we observed that recovery from radiation-induced attenuation of pulmonary vascular reactivity occurred. In the present study, we report that deterioration results in several vascular parameters for {<=}1 year after 10 Gy, suggesting sustained remodeling of the pulmonary vasculature. Our data support clinically relevant injuries that appear in a time- and dose-related manner after exposure to relatively low radiation doses.

  11. Gold Nanoparticles and Microwave Irradiation Inhibit Beta-Amyloid Amyloidogenesis

    NASA Astrophysics Data System (ADS)

    Araya, Eyleen; Olmedo, Ivonne; Bastus, Neus G.; Guerrero, Simón; Puntes, Víctor F.; Giralt, Ernest; Kogan, Marcelo J.

    2008-11-01

    Peptide-Gold nanoparticles selectively attached to β-amyloid protein (Aβ) amyloidogenic aggregates were irradiated with microwave. This treatment produces dramatic effects on the Aβ aggregates, inhibiting both the amyloidogenesis and the restoration of the amyloidogenic potential. This novel approach offers a new strategy to inhibit, locally and remotely, the amyloidogenic process, which could have application in Alzheimer’s disease therapy. We have studied the irradiation effect on the amyloidogenic process in the presence of conjugates peptide-nanoparticle by transmission electronic microscopy observations and by Thioflavine T assays to quantify the amount of fibrils in suspension. The amyloidogenic aggregates rather than the amyloid fibrils seem to be better targets for the treatment of the disease. Our results could contribute to the development of a new therapeutic strategy to inhibit the amyloidogenic process in Alzheimer’s disease.

  12. Gold Nanoparticles and Microwave Irradiation Inhibit Beta-Amyloid Amyloidogenesis

    PubMed Central

    2008-01-01

    Peptide-Gold nanoparticles selectively attached to β-amyloid protein (Aβ) amyloidogenic aggregates were irradiated with microwave. This treatment produces dramatic effects on the Aβ aggregates, inhibiting both the amyloidogenesis and the restoration of the amyloidogenic potential. This novel approach offers a new strategy to inhibit, locally and remotely, the amyloidogenic process, which could have application in Alzheimer’s disease therapy. We have studied the irradiation effect on the amyloidogenic process in the presence of conjugates peptide-nanoparticle by transmission electronic microscopy observations and by Thioflavine T assays to quantify the amount of fibrils in suspension. The amyloidogenic aggregates rather than the amyloid fibrils seem to be better targets for the treatment of the disease. Our results could contribute to the development of a new therapeutic strategy to inhibit the amyloidogenic process in Alzheimer’s disease.

  13. Niacin Suppresses Progression of Atherosclerosis by Inhibiting Vascular Inflammation and Apoptosis of Vascular Smooth Muscle Cells.

    PubMed

    Su, Gang; Sun, Guangli; Liu, Hai; Shu, Liliang; Zhang, Jingchao; Guo, Longhui; Huang, Chen; Xu, Jing

    2015-12-29

    BACKGROUND Niacin is a broad-spectrum lipid-regulating drug used for the clinical therapy of atherosclerosis; however, the mechanisms by which niacin ameliorates atherosclerosis are not clear. MATERIAL AND METHODS The effect of niacin on atherosclerosis was assessed by detection of atherosclerotic lesion area. Adhesion molecules in arterial endothelial cells were determined by using qRT-PCR and Western blot analysis. The levels of serum inflammatory cytokines in ApoE-/- mice were detected by using ELISA. We detected the expression levels of phosphorylated nuclear factors-kB (NF-κB) p65 in aortic endothelial cells of mice using Western blot analysis. Furthermore, we investigated the anti-inflammation effect and endothelium-protecting function of niacin and their regulatory mechanisms in vitro. RESULTS Niacin inhibited the progress of atherosclerosis and decreased the levels of serum inflammatory cytokines and adhesion molecules in ApoE-/- mice. Niacin suppressed the activity of NF-κB and apoptosis of vascular smooth muscle cells (VSMCs). Furthermore, niacin induced phosphorylated focal adhesion kinase (FAK) and FAK inhibitor PF-573228 reduced the level of Bcl-2 and elevated the level of cleaved caspase-3 in VSMCs. CONCLUSIONS Niacin inhibits vascular inflammation and apoptosis of VSMCs via inhibiting the NF-κB signaling and the FAK signaling pathway, respectively, thus protecting ApoE-/- mice against atherosclerosis.

  14. Niacin Suppresses Progression of Atherosclerosis by Inhibiting Vascular Inflammation and Apoptosis of Vascular Smooth Muscle Cells

    PubMed Central

    Su, Gang; Sun, Guangli; Liu, Hai; Shu, Liliang; Zhang, Jingchao; Guo, Longhui; Huang, Chen; Xu, Jing

    2015-01-01

    Background Niacin is a broad-spectrum lipid-regulating drug used for the clinical therapy of atherosclerosis; however, the mechanisms by which niacin ameliorates atherosclerosis are not clear. Material/Methods The effect of niacin on atherosclerosis was assessed by detection of atherosclerotic lesion area. Adhesion molecules in arterial endothelial cells were determined by using qRT-PCR and Western blot analysis. The levels of serum inflammatory cytokines in ApoE−/− mice were detected by using ELISA. We detected the expression levels of phosphorylated nuclear factors-κB (NF-κB) p65 in aortic endothelial cells of mice using Western blot analysis. Furthermore, we investigated the anti-inflammation effect and endothelium-protecting function of niacin and their regulatory mechanisms in vitro. Results Niacin inhibited the progress of atherosclerosis and decreased the levels of serum inflammatory cytokines and adhesion molecules in ApoE−/− mice. Niacin suppressed the activity of NF-κB and apoptosis of vascular smooth muscle cells (VSMCs). Furthermore, niacin induced phosphorylated focal adhesion kinase (FAK) and FAK inhibitor PF-573228 reduced the level of Bcl-2 and elevated the level of cleaved caspase-3 in VSMCs. Conclusions Niacin inhibits vascular inflammation and apoptosis of VSMCs via inhibiting the NF-κB signaling and the FAK signaling pathway, respectively, thus protecting ApoE−/− mice against atherosclerosis. PMID:26712802

  15. Loss of vascular fibrinolytic activity following irradiation of the liver--an aspect of late radiation damage

    SciTech Connect

    Henderson, B.W.; Bicher, H.I.; Johnson, R.J.

    1983-09-01

    The vascular fibrinolytic activity, known to originate from the endothelium, was studied histochemically by fibrinolysis autography in liver samples from beagles exposed to radiation treatment. Eighteen to thirty months prior to sacrifice, six dogs received X irradiation (4600 rad in 5 weeks) and three dogs received X irradiation plus aspirin (1 g/kg). Two dogs served as untreated controls. Control livers showed extensive fibrinolytic activity related to large and small vascular structures. The vascular fibrinolytic activity had been lost from all vessels except the major portal branches in five irradiated livers and was severely diminished in three. One irradiated liver appeared to possess normal fibrinolytic activity.

  16. Troglitazone inhibits vascular smooth muscle cell growth and intimal hyperplasia.

    PubMed Central

    Law, R E; Meehan, W P; Xi, X P; Graf, K; Wuthrich, D A; Coats, W; Faxon, D; Hsueh, W A

    1996-01-01

    Vascular smooth muscle cell (VSMC) proliferation and migration are responses to arterial injury that are highly important to the processes of restenosis and atherosclerosis. In the arterial balloon injury model in the rat, platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF) are induced in the vessel wall and regulate these VSMC activities. Novel insulin sensitizing agents, thiazolidinediones, have been demonstrated to inhibit insulin and epidermal growth factor-induced growth of VSMCs. We hypothesized that these agents might also inhibit the effect of PDGF and bFGF on cultured VSMCs and intimal hyperplasia in vivo. Troglitazone (1 microM), a member of the thiazolidinedione class, produced a near complete inhibition of both bFGF-induced DNA synthesis as measured by bromodeoxyuridine incorporation (6.5+/-3.9 vs. 17.6+/-4.3% cells labeled, P < 0.05) and c-fos induction. This effect was associated with an inhibition (by 73+/-4%, P < 0.01) by troglitazone of the transactivation of the serum response element, which regulates c-fos expression. Inhibition of c-fos induction by troglitazone appeared to occur via a blockade of the MAP kinase pathway at a point downstream of MAP kinase activation by MAP kinase kinase. At this dose, troglitazone also inhibited PDGF-BB-directed migration of VSMC (by 70+/-6%, P < 0.01). These in vitro effects were operative in vivo. Quantitative image analysis revealed that troglitazone-treated rats had 62% (P < 0.001) less neointima/media area ratio 14 d after balloon injury of the aorta compared with injured rats that received no troglitazone. These results suggest troglitazone is a potent inhibitor of VSMC proliferation and migration and, thus, may be a useful agent to prevent restenosis and possibly atherosclerosis. PMID:8878442

  17. Moving Beyond JUPITER: Will Inhibiting Inflammation Reduce Vascular Event Rates?

    PubMed Central

    Ridker, Paul M

    2013-01-01

    The recent JUPITER trial demonstrated that potent statin therapy reduces by 50 percent the risk of heart attack and stroke among men and women with low levels of LDL-cholesterol who are at increased vascular risk due to elevated levels of CRP, a biomarker of low-grade systemic inflammation. In JUPITER, both absolute risk and the absolute risk reduction with statin therapy in JUPITER were related to the level of CRP whereas no such relationship was observed for LDL-C. Further, on-treatment levels of CRP and LDL-C were independently associated with residual risk, and the genetic determinants of statin-induced CRP reduction differed from the genetic determinants of statin-induced LDL reduction. Despite these data, it is impossible in any statin trial to establish whether the clinical benefits of treatment are due to LDL-reduction alone, to inflammation inhibition, or to a combination of both processes To address the hypothesis that lowering inflammation will lower vascular event rates, two large-scale placebo controlled trials using targeted anti-inflammatory agents for the secondary prevention of myocardial infarction have been initiated. The first trial, the Canakinumab Anti-Inflammatory Thrombosis Outcomes Study (CANTOS) is evaluating whether interleukin-1β (IL-1β) inhibition as compared to placebo can reduce rates of recurrent myocardial infarction, stroke, and cardiovascular death among stable coronary artery disease patients who remain at high vascular risk due to persistent elevations of hsCRP (≥2 mg/L) despite contemporary secondary prevention strategies. The second trial, the Cardiovascular Inflammation Reduction Trial (CIRT) has been funded by the NHLBI and will evaluate whether low dose methotrexate (target dose 20 mg/week) as compared to placebo will reduce major vascular events among a group of post-myocardial infarction patients with either diabetes or metabolic syndrome, groups known to have high risk on the basis of a persistent pro

  18. Reconstruction with vascularized composite tissue in patients with excessive injury following surgery and irradiation

    SciTech Connect

    Serafin, D.; DeLand, M.; Lesesne, C.B.; Smith, P.J.; Noell, K.T.; Georgiade, N.

    1982-01-01

    The biological effects of a single high dose of radiation are examined. Both cellular injury and repair are reviewed during early, intermediate, and late phases. Anticipated composite tissue morbidity is detailed for therapeutic radiation doses administered to the head and neck, breast and thorax, and perineum. Patients who demonstrated excessive time-dose fractionation values were irradiated with lower x-ray energies. Those in whom there was an overlap of treatment fields presented a serious challenge to the reconstructive surgeon. Judicious selection of well-vascularized composite tissue outside the portals of irradiation, preferably with a long vascular pedicle, facilitated reconstruction. When possible, both donor and recipient vasculature should be outside the irradiated area to ensure uninterrupted blood flow to the transferred or transplanted tissue.

  19. Gamma irradiation inhibits wound induced browning in shredded cabbage.

    PubMed

    Banerjee, Aparajita; Suprasanna, Penna; Variyar, Prasad S; Sharma, Arun

    2015-04-15

    Gamma-radiation induced browning inhibition in minimally processed shredded cabbage stored (10 °C) for up to 8 days was investigated. γ-irradiation (2 kGy) resulted in inhibition of browning as a result of down-regulation (1.4-fold) in phenylalanine ammonia lyase (PAL) gene expression and a consequent decrease in phenylalanine ammonia lyase (PAL) activity. Activity of polyphenol oxidase and peroxidase, total and individual phenolic content as well as o-quinone concentration were, however, unaffected. In the non-irradiated samples, PAL activity increased as a consequence of up-regulation of PAL gene expression after 24 and 48 h by 1.2 and 7.7-fold, respectively, during storage that could be linearly correlated with enhanced quinone formation and browning. Browning inhibition in radiation processed shredded cabbage as a result of inhibition of PAL activity was thus clearly demonstrated. The present work provides an insight for the first time on the mechanism of browning inhibition at both biochemical and genetic level. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Inhibition of vascular permeability by antisense-mediated inhibition of plasma kallikrein and coagulation factor 12.

    PubMed

    Bhattacharjee, Gourab; Revenko, Alexey S; Crosby, Jeffrey R; May, Chris; Gao, Dacao; Zhao, Chenguang; Monia, Brett P; MacLeod, A Robert

    2013-06-01

    Hereditary angioedema (HAE) is a rare disorder characterized by recurrent, acute, and painful episodes of swelling involving multiple tissues. Deficiency or malfunction of the serine protease inhibitor C1 esterase inhibitor (C1-INH) results in HAE types 1 and 2, respectively, whereas mutations in coagulation factor 12 (f12) have been associated with HAE type 3. C1-INH is the primary inhibitor of multiple plasma cascade pathways known to be altered in HAE patients, including the complement, fibrinolytic, coagulation, and kinin-kallikrein pathways. We have selectively inhibited several components of both the kinin-kallikrein system and the coagulation cascades with potent and selective antisense oligonucleotides (ASOs) to investigate their relative contributions to vascular permeability. We have also developed ASO inhibitors of C1-INH and characterized their effects on vascular permeability in mice as an inducible model of HAE. Our studies demonstrate that ASO-mediated reduction in C1-INH plasma levels results in increased vascular permeability and that inhibition of proteases of the kinin-kallikrein system, either f12 or prekallikrein (PKK) reverse the effects of C1-INH depletion with similar effects on both basal and angiotensin converting enzyme (ACE) inhibitor-induced permeability. In contrast, inhibition of coagulation factors 11 (f11) or 7 (f7) had no effect. These results suggest that the vascular defects observed in C1-INH deficiency are dependent on the kinin-kallikrein system proteases f12 and PKK, and not mediated through the coagulation pathways. In addition, our results highlight a novel therapeutic modality that can potentially be employed prophylactically to prevent attacks in HAE patients.

  1. Iron ion irradiation increases promotes adhesion of monocytic cells to arterial vascular endothelium

    NASA Astrophysics Data System (ADS)

    Kucik, Dennis; Khaled, Saman; Gupta, Kiran; Wu, Xing; Yu, Tao; Chang, Polly; Kabarowski, Janusz

    Radiation causes inflammation, and chronic, low-level vascular inflammation is a risk factor for atherosclerosis. Consistent with this, exposure to radiation from a variety of sources is associated with increased risk of heart disease and stroke. Part of the inflammatory response to radiation is a change in the adhesiveness of the endothelial cells that line the blood vessels, triggering inappropriate accumulation of leukocytes, leading to later, damaging effects of inflammation. Although some studies have been done on the effects of gamma irradiation on vascular endothelium, the response of endothelium to heavy ion radiation likely to be encountered in prolonged space flight has not been determined. We investigated how irradiation of aortic endothelial cells with iron ions affects adhesiveness of cultured aortic endothelial cells for monocytic cells and the consequences of this for development of atherosclerosis. Aortic endothelial cells were irradiated with 600 MeV iron ions at Brookhaven National Laboratory and adhesion-related changes were measured. Cells remained viable for at least 72 hours, and were even able to repair acute damage to cell junctions. We found that iron ion irradiation altered expression levels of specific endothelial cell adhesion molecules. Further, these changes had functional consequences. Using a flow chamber adhesion assay to measure adhesion of monocytic cells to endothelial cells under physiological shear stress, we found that adhesivity of vascular endothelium was enhanced in as little as 24 hours after irradiation. Further, the radiation dose dependence was not monotonic, suggesting that it was not simply the result of endothelial cell damage. We also irradiated aortic arches and carotid arteries of Apolipoprotein-E-deficient mice. Histologic analysis of these mice will be conducted to determine whether effects of radiation on endothelial adhesiveness result in consequences for development of atherosclerosis. (Supported by NSBRI

  2. Blood vessel damage correlated with irradiance for in vivo vascular targeted photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Zhang, Jinde; Tan, Zou; Niu, Xiangyu; Lin, Linsheng; Lin, Huiyun; Li, Buhong

    2016-10-01

    Vascular targeted photodynamic therapy (V-PDT) has been widely utilized for the prevention or treatment of vascular-related diseases, including age-related macular degeneration, port-wine stains and prostate cancer. In order to quantitative assessment the blood vessel damage during V-PDT, nude mice were implanted with Titanium dorsal skin window chambers for in vivo V-PDT studies. For treatments, various irradiances including 50, 75, 100 and 200 mW/cm2 provided by a 532 nm semiconductor laser were performed with the same total light dose of 30 J/cm2 after the mice were intravenously injection of Rose Bengal for 25 mg/Kg body weight. Laser speckle imaging and microscope were used to monitor blood flow dynamics and vessel constriction during and after V-PDT, respectively. The V-PDT induced vessel damages between different groups were compared. The results show that significant difference in blood vessel damage was found between the lower irradiances (50, 75 and 100 mW/cm2) and higher irradiance (200 mW/cm2), and the blood vessel damage induced by V-PDT is positively correlated with irradiance. This study implies that the optimization of irradiance is required for enhancing V-PDT therapeutic efficiency.

  3. Globular adiponectin reduces vascular calcification via inhibition of ER-stress-mediated smooth muscle cell apoptosis.

    PubMed

    Lu, Yan; Bian, Yunfei; Wang, Yueru; Bai, Rui; Wang, Jiapu; Xiao, Chuanshi

    2015-01-01

    This study aims to explore the mechanism of globular adiponectin inhibiting vascular calcification. We established drug-induced rat vascular calcification model, globular adiponectin was given to observe the effect of globular Adiponectin on the degree of calcification. The markers of vascular calcification and apoptosis were also investigated. Meanwhile, the in vitro effect of globular Adiponectin on vascular calcification was also evaluated using primary cultured rat vascular smooth muscle cells. We found that globular adiponectin could inhibit drug-induced rat vascular calcification significantly in vivo. The apoptosis of vascular smooth muscle cells was also reduced. The possible mechanism could be the down-regulation of endoplasmic reticulum stress by globular adiponectin. Experiments in primary cultured vascular smooth muscle cells also confirmed that globular adiponectin could reduce cell apoptosis to suppress vascular calcification via inhibition of endoplasmic reticulum stress. This study confirmed that globular adiponectin could suppress vascular calcification; one of the mechanisms could be inhibition of endoplasmic reticulum stress to reduce cell apoptosis. It could provide an effective method in the therapy of vascular calcification-associated diseases.

  4. Globular adiponectin reduces vascular calcification via inhibition of ER-stress-mediated smooth muscle cell apoptosis

    PubMed Central

    Lu, Yan; Bian, Yunfei; Wang, Yueru; Bai, Rui; Wang, Jiapu; Xiao, Chuanshi

    2015-01-01

    Objective: This study aims to explore the mechanism of globular adiponectin inhibiting vascular calcification. Methods: We established drug-induced rat vascular calcification model, globular adiponectin was given to observe the effect of globular Adiponectin on the degree of calcification. The markers of vascular calcification and apoptosis were also investigated. Meanwhile, the in vitro effect of globular Adiponectin on vascular calcification was also evaluated using primary cultured rat vascular smooth muscle cells. Results: We found that globular adiponectin could inhibit drug-induced rat vascular calcification significantly in vivo. The apoptosis of vascular smooth muscle cells was also reduced. The possible mechanism could be the down-regulation of endoplasmic reticulum stress by globular adiponectin. Experiments in primary cultured vascular smooth muscle cells also confirmed that globular adiponectin could reduce cell apoptosis to suppress vascular calcification via inhibition of endoplasmic reticulum stress. Conclusions: This study confirmed that globular adiponectin could suppress vascular calcification; one of the mechanisms could be inhibition of endoplasmic reticulum stress to reduce cell apoptosis. It could provide an effective method in the therapy of vascular calcification-associated diseases. PMID:26045760

  5. The irradiated tumor microenvironment: role of tumor-associated macrophages in vascular recovery

    PubMed Central

    Russell, Jeffery S.; Brown, J. Martin

    2013-01-01

    Radiotherapy is an important modality used in the treatment of more than 50% of cancer patients in the US. However, despite sophisticated techniques for radiation delivery as well as the combination of radiation with chemotherapy, tumors can recur. Thus, any method of improving the local control of the primary tumor by radiotherapy would produce a major improvement in the curability of cancer patients. One of the challenges in the field is to understand how the tumor vasculature can regrow after radiation in order to support tumor recurrence, as it is unlikely that any of the endothelial cells within the tumor could survive the doses given in a typical radiotherapy regimen. There is now considerable evidence from both preclinical and clinical studies that the tumor vasculature can be restored following radiotherapy from an influx of circulating cells consisting primarily of bone marrow derived monocytes and macrophages. The radiation-induced influx of bone marrow derived cells (BMDCs) into tumors can be prevented through the blockade of various cytokine pathways and such strategies can inhibit tumor recurrence. However, the post-radiation interactions between surviving tumor cells, recruited immune cells, and the remaining stroma remain poorly defined. While prior studies have described the monocyte/macrophage inflammatory response within normal tissues and in the tumor microenvironment, less is known about this response with respect to a tumor after radiation therapy. The goal of this review is to summarize existing research studies to provide an understanding of how the myelomonocytic lineage may influence vascular recovery within the irradiated tumor microenvironment. PMID:23882218

  6. Early changes in vascular reactivity in response to 56Fe irradiation in ApoE-/- mice

    NASA Astrophysics Data System (ADS)

    White, C. Roger; Yu, Tao; Gupta, Kiran; Babitz, Stephen K.; Black, Leland L.; Kabarowski, Janusz H.; Kucik, Dennis F.

    2015-03-01

    Epidemiological studies have established that radiation from a number of terrestrial sources increases the risk of atherosclerosis. The accelerated heavy ions in the galacto-cosmic radiation (GCR) that astronauts will encounter on in space, however, interact very differently with tissues than most types of terrestrial radiation, so the health consequences of exposure on deep-space missions are not clear. We demonstrated earlier that 56Fe, an important component of cosmic radiation, accelerates atherosclerotic plaque development. In the present study, we examined an earlier, pro-atherogenic event that might be predictive of later atherosclerotic disease. Decreased endothelium-dependent vasodilation is a prominent manifestation of vascular dysfunction that is thought to predispose humans to the development of structural vascular changes that precede the development of atherosclerotic plaques. To test the effect of heavy-ion radiation on endothelium-dependent vasodilation, we used the same ApoE-/- mouse model in which we previously demonstrated the pro-atherogenic effect of 56Fe on plaque development. Ten week old male ApoE mice (an age at which there is little atherosclerotic plaque in the descending aorta) were exposed to 2.6 Gy 56Fe. The mice were then fed a normal diet and housed under standard conditions. At 4-5 weeks post-irradiation, aortic rings were isolated and endothelial-dependent relaxation was measured. Relaxation in response to acetylcholine was significantly impaired in irradiated mice compared to age-matched, un-irradiated mice. This decrease in vascular reactivity following 56Fe irradiation occurred eight weeks prior to the development of statistically significant exacerbation of aortic plaque formation and may contribute to the formation of later atherosclerotic lesions.

  7. Topical formulation containing hesperidin methyl chalcone inhibits skin oxidative stress and inflammation induced by ultraviolet B irradiation.

    PubMed

    Martinez, Renata M; Pinho-Ribeiro, Felipe A; Steffen, Vinicius S; Caviglione, Carla V; Pala, Danilo; Baracat, Marcela M; Georgetti, Sandra R; Verri, Waldiceu A; Casagrande, Rubia

    2016-04-01

    Skin exposure to ultraviolet B (UVB) irradiation has increased significantly in recent years due to ozone depletion, and it represents the main cause of many skin diseases. Hesperidin methyl chalcone (HMC) is a compound used to treat vascular diseases that has demonstrated anti-inflammatory activities in pre-clinical studies. Herein, we tested the antioxidant activity of HMC in cell free systems and the in vivo effects of a stable topical formulation containing HMC in a mouse model of skin oxidative stress and inflammation induced by UVB irradiation. HMC presented ferric reducing power, neutralized 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and hydroxyl free radicals, and inhibited lipid peroxidation. In hairless mice, a topical formulation containing HMC inhibited UVB irradiation-induced skin edema, depletion of antioxidant capacity (ferric and ABTS reducing abilities and catalase activity), lipid peroxidation, superoxide anion production and mRNA expression of gp91phox (nicotinamide adenine dinucleotide phosphate [NADPH] oxidase 2 sub-unity). In addition, HMC inhibited UVB irradiation-induced depletion of reduced glutathione levels by maintaining glutathione peroxidase-1 and glutathione reductase mRNA expression, prevented down-regulation of nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA expression and increased heme oxygenase-1 mRNA expression. Finally, we demonstrated that topical application of the formulation containing HMC inhibited cytokine (TNF-α, IL-1β, IL-6, and IL-10) production induced by UVB irradiation. Therefore, this topical formulation containing HMC is a promising new therapeutic approach to protecting the skin from the deleterious effects of UVB irradiation.

  8. Inhibition of corneal neovascularization by vascular endothelia growth inhibitor gene

    PubMed Central

    Wang, Hong; Wang, Bing; Zhang, Zhen-Hai

    2010-01-01

    AIM To evaluate the effect of Effectene™ lipofectine mediated plasmids encoding human pcDNA4-vascular endothelia growth inhibitor (pcDNA4-VEGI) gene on corneal neovascularization (CNV). METHODS Forty New Zealand albino rabbits were sutured by 5-0 silk on the superior cornea to establish the animal model and divided into 4 random group, ten per each group: group A: transfected by pcDNA4-VEGI gene mediated by Effectene™ lipofectine transfection, group B: by Plasmid pcDNA4, group C: by Effectene™, and group D: by normal saline. Length and area of CNV were measured under slit lamp every day after transfection, immunohistochemistry was used to detected the expression of VEGI protein in cornea at 3, 7, 14 and 21 days. RESULTS Average occurrence of CNV in the pcDNA4-VEGI gene transfected group (group A) was 6.3 days, in plasmid pcDNA4 control group (group B) was 3.1 days, in Effectene™ lipofectine control group (group C) was 3.2 days, in normal saline control group (group D) was 3.2 days. Differences between groups A and B, C, D were statistically significant (P<0.01), while differences in groups B, C and D were meaningless (P>0.05). Lenth and average area of CNV in each period in group A was meaningful different from that in groups B, C, and D (P<0.01), while differences in group B, C and D were meaningless (P>0.05). Immunohistochemistry result: VEGI positive cells could be seen in epithelium, stroma, endothelium and the cliff of CNV in group A at 3 days after transfection. VEGI cells changed with the decrease of CNV. None positive cells were in the control groups (groups B, C and D) all the time. CONCLUSION Effectene™ lipofectine transfection technique can be effectively used in transfecting pcDNA4-VEGI gene into rabbit cornea and the lenth and areas of CNV can be inhibited by VEGI gene. PMID:22553552

  9. Boron neutron capture irradiation of the rat spinal cord: histopathological evidence of a vascular-mediated pathogenesis.

    PubMed

    Morris, G M; Coderre, J A; Bywaters, A; Whitehouse, E; Hopewell, J W

    1996-09-01

    A histopathological study was carried out on the spinal cord of rats after boron neutron capture (BNC) irradiation. Rats were irradiated with thermal neutrons alone or in combination with borocaptate sodium (BSH) or p-boronophenylalanine (BPA). Spinal cords were examined 1 year after irradiation, or at earlier times in rats developing myelopathy. Considered overall, the pathology of the spinal cord after BNC irradiation was comparable with that reported previously after X irradiation of the spinal cord in the identical strain of rat. When BSH was used as the neutron capture agent, the biologically effective dose of radiation delivered to the CNS parenchyma was a factor of -2.7 lower than that delivered to the vascular endothelium. In effect, the blood vessels were selectively irradiated using this BNC modality. The resultant pathology was similar to that observed after irradiation with thermal neutrons alone or in the presence of BPA, situations in which the CNS vasculature was not selectively irradiated. This points to the vascular endothelium as being the critical target cell population, damage to which results in the development of the lesions seen in the spinal cord after BNC irradiation and, by inference, after irradiation with more conventional modalities.

  10. Boron neutron capture irradiation of the rat spinal cord: Histopathological evidence of a vascular-mediated pathogenesis

    SciTech Connect

    Morris, G. M.; Bywaters, A.; Hopewell, J.W.; Coderre, J.A.

    1996-09-01

    A histopathological study was carried out on the spinal cord of rats after boron neutron capture (BNC) irradiation. Rats were irradiated with thermal neutrons alone or in combination with borocaptate sodium (BSH) or p-boronophenylalanine (BPA). Spinal cords were examined 1 year after irradiation, or at earlier times in rats developing myelothapy. Considered overall, the pathology of the spinal cord after BNC irradiation was comparable with that reported previously after X irradiation of the spinal cord in the identical strain of rat. When BSH was used as the neutron capture agent, the biologically effective dose of radiation delivered to the CNS parechyma was a factor of {approx}2.7 lower than that delivered to the vascular endothelium. In effect, the blood vessels were selectively irradiated using this BNC modality. The resultant pathology was similar to that observed after irradiation with thermal neutrons alone or in the presence of BPA, situations in which the CNS vasculature was not selectively irradiated. This points to the vascular endothelium as being the critical target cell population, damage to which results in the development of the lesions seen in the spinal cord after BNC irradiation and, by inference, after irradiation with more conventional modalities. 37 refs., 6 figs., 4 tabs.

  11. Class 3 semaphorins control vascular morphogenesis by inhibiting integrin function.

    PubMed

    Serini, Guido; Valdembri, Donatella; Zanivan, Sara; Morterra, Giulia; Burkhardt, Constanze; Caccavari, Francesca; Zammataro, Luca; Primo, Luca; Tamagnone, Luca; Logan, Malcolm; Tessier-Lavigne, Marc; Taniguchi, Masahiko; Püschel, Andreas W; Bussolino, Federico

    2003-07-24

    The motility and morphogenesis of endothelial cells is controlled by spatio-temporally regulated activation of integrin adhesion receptors, and integrin activation is stimulated by major determinants of vascular remodelling. In order for endothelial cells to be responsive to changes in activator gradients, the adhesiveness of these cells to the extracellular matrix must be dynamic, and negative regulators of integrins could be required. Here we show that during vascular development and experimental angiogenesis, endothelial cells generate autocrine chemorepulsive signals of class 3 semaphorins (SEMA3 proteins) that localize at nascent adhesive sites in spreading endothelial cells. Disrupting endogenous SEMA3 function in endothelial cells stimulates integrin-mediated adhesion and migration to extracellular matrices, whereas exogenous SEMA3 proteins antagonize integrin activation. Misexpression of dominant negative SEMA3 receptors in chick embryo endothelial cells locks integrins in an active conformation, and severely impairs vascular remodelling. Sema3a null mice show vascular defects as well. Thus during angiogenesis endothelial SEMA3 proteins endow the vascular system with the plasticity required for its reshaping by controlling integrin function.

  12. Taurine inhibits osteoblastic differentiation of vascular smooth muscle cells via the ERK pathway.

    PubMed

    Liao, Xiao-bo; Zhou, Xin-min; Li, Jian-ming; Yang, Jin-fu; Tan, Zhi-ping; Hu, Zhuo-wei; Liu, Wei; Lu, Ying; Yuan, Ling-qing

    2008-05-01

    Vascular calcification develops within atherosclerotic lesions and results from a process similar to osteogenesis. Taurine is a free beta-amino acid and plays an important physiological role in mammals. We have recently demonstrated that vascular smooth muscle cells (VSMCs) express a functional taurine transporter. To evaluate the possible role of taurine in vascular calcification, we assessed its effects on osteoblastic differentiation of VSMCs in vitro. The results showed that taurine inhibited the beta-glycerophosphate-induced osteoblastic differentiation of VSMCs as evidenced by both the decreasing alkaline phosphate (ALP) activity and expression of the core binding factor alpha1 (Cbfalpha1). Taurine also activated the extracellular signal-regulated protein kinase (ERK) pathway. Inhibition of ERK pathway reversed the effect of taurine on ALP activity and Cbfalpha1 expression. These results suggested that taurine inhibited osteoblastic differentiation of vascular cells via the ERK pathway.

  13. Effects of single and fractionated low-dose irradiation on vascular endothelial cells.

    PubMed

    Cervelli, Tiziana; Panetta, Daniele; Navarra, Teresa; Andreassi, Maria Grazia; Basta, Giuseppina; Galli, Alvaro; Salvadori, Piero A; Picano, Eugenio; Del Turco, Serena

    2014-08-01

    An increasing number of epidemiological studies suggest that chronic low-dose irradiation increases the risk of atherosclerosis. We evaluated and compared the in vitro biological effects of both single and fractionated low-doses of X-ray irradiation on endothelial cells. Human umbilical vein endothelial cells (HUVECs) were irradiated with X-rays, with single doses of 0.125, 0.25 and 0.5 Gy or fractionated doses of 2 × 0.125 Gy and 2 × 0.25 Gy, with 24 h interfraction interval. Survival, apoptosis, reactive oxygen species (ROS) production, nuclear factor-κB (NF-κB) activation, intercellular adhesion molecule-1 (ICAM-1) expression, HUVEC adhesiveness and DNA damage were investigated. We did not observe any effect on viability and apoptosis. Both single and fractionated doses induced ROS generation, NF-κB activation, ICAM-1 protein expression and HUVEC adhesiveness, but only fractionated doses increase significantly ICAM-1 mRNA. The effects measured after fractionated dose result always higher than those induced by the single dose. Moreover, we observed that DNA double strand break (DSB), visualized with γ-H2AX foci, is dose-dependent and that the kinetics of γ-H2AX foci is not affected by fractionated doses. We showed that single and fractionated low-dose irradiations with low energy X-rays do not affect cell viability and DNA repair. Interestingly, the greater increase of ICAM-1 surface exposure and endothelial adhesiveness observed after fractionated irradiation, suggests that fractionated low-doses may accelerate chronic vascular inflammation, from which the atherosclerotic process can arise. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Application of gamma irradiation for inhibition of food allergy

    NASA Astrophysics Data System (ADS)

    Byun, Myung-Woo; Lee, Ju-Woon; Yook, Hong-Sun; Jo, Cheorun; Kim, Hee-Yun

    2002-03-01

    This study was carried out to evaluate the application of food irradiation technology as a method for reducing food allergy. Milk β-lactoglobulin, chicken egg albumin, and shrimp tropomyosin were used as model food allergens for experiments on allergenic and molecular properties by gamma irradiation. The amount of intact allergens in an irradiated solution was reduced by gamma irradiation depending upon the dose. These results showed that epitopes on the allergens were structurally altered by radiation treatment and that the irradiation technology can be applied to reduce allergenicity of allergic foods.

  15. TNFSF15 inhibits VEGF-stimulated vascular hyperpermeability by inducing VEGFR2 dephosphorylation.

    PubMed

    Yang, Gui-Li; Zhao, Zilong; Qin, Ting-Ting; Wang, Dong; Chen, Lijuan; Xiang, Rong; Xi, Zhen; Jiang, Rongcai; Zhang, Zhi-Song; Zhang, Jianning; Li, Lu-Yuan

    2017-02-09

    Vascular hyperpermeability is critical in ischemic diseases, including stroke and myocardial infarction, as well as in inflammation and cancer. It is well known that the VEGF-VEGFR2 signaling pathways are pivotal in promoting vascular permeability; however, counterbalancing mechanisms that restrict vascular permeability to maintain the integrity of blood vessels, are not yet fully understood. We report that TNF superfamily member 15 (TNFSF15), a cytokine largely produced by vascular endothelial cells and a specific inhibitor of the proliferation of these same cells, can inhibit VEGF-induced vascular permeability in vitro and in vivo, and that death receptor 3 (DR3), a cell surface receptor of TNFSF15, mediates TNFSF15-induced dephosphorylation of VEGFR2. Src homology region 2 domain-containing phosphatase-1 (SHP-1) becomes associated with DR3 upon TNFSF15 interaction with the latter. In addition, a protein complex consisting of VEGFR2, DR3, and SHP-1 is formed in response to the effects of TNFSF15 and VEGF on endothelial cells. It is plausible that this protein complex provides a structural basis for the molecular mechanism in which TNFSF15 induces the inhibition of VEGF-stimulated vascular hyperpermeability.-Yang, G.-L., Zhao, Z., Qin, T.-T., Wang, D., Chen, L., Xiang, R., Xi, Z., Jiang, R., Zhang, Z.-S., Zhang, J., Li. L.-Y. TNFSF15 inhibits VEGF-stimulated vascular hyperpermeability by inducing VEGFR2 dephosphorylation.

  16. Inhibition of chronic rejection by antibody induced vascular accommodation in fully allogeneic heart allografts.

    PubMed

    Semiletova, Natalya V; Shen, Xiu-Da; Baibakov, Boris; Feldman, Daniel M; Mukherjee, Kaushik; Frank, Jonathan M; Stepkowski, Stainslaw M; Busuttil, Ronald W; Kupiec-Weglinski, Jerzy W; Ghobrial, Rafik M

    2005-12-15

    The potential role of altered antibody responses as an effector protective mechanism to induce graft accommodation has been widely investigated in xenogeneic responses. Here we investigate the protective effects of antibody binding to vascular endothelium in a fully mismatched allogeneic model of heart transplantation. ACI recipients of WF cardiac grafts were treated either with allochimeric [alpha1h ]-RT1.A class I major histocompatibility complex (MHC) extracts (1 mg/rat, p.v. day 0) or high dose of CsA (10 mg/kg/day, p.o., day 0-6). Cardiac allografts were evaluated at 100 days posttransplant by immunohistology for evidence of chronic rejection and/or vascular accommodation. Activation of apoptotic or antiapoptotic mechanisms was verified by DNA fragmentation (TUNEL) analysis. Allochimeric therapy resulted in inhibition of chronic rejection, absence of neointimal formation and induction of vascular accommodation of fully allogeneic WF hearts in ACI hosts. Such accommodation was evident by IgG and IgM vascular endothelial binding and marked reduction of DNA fragmentation. In contrast, CsA therapy resulted in marked neointimal proliferation, without evidence of vascular accommodation. Immunohistochemical analysis failed to demonstrate vascular endothelial antibody binding. Further, severe chronic rejection following CsA treatment was accompanied by marked DNA fragmentation. Alteration of humoral immunity induces vascular accommodation in allogeneic transplantation. Vascular accommodation is the underlying mechanism for inhibition allograft vasculopathy following allochimeric MHC class I therapy.

  17. Drinking citrus fruit juice inhibits vascular remodeling in cuff-induced vascular injury mouse model.

    PubMed

    Ohnishi, Arika; Asayama, Rie; Mogi, Masaki; Nakaoka, Hirotomo; Kan-No, Harumi; Tsukuda, Kana; Chisaka, Toshiyuki; Wang, Xiao-Li; Bai, Hui-Yu; Shan, Bao-Shuai; Kukida, Masayoshi; Iwanami, Jun; Horiuchi, Masatsugu

    2015-01-01

    Citrus fruits are thought to have inhibitory effects on oxidative stress, thereby attenuating the onset and progression of cancer and cardiovascular disease; however, there are few reports assessing their effect on vascular remodeling. Here, we investigated the effect of drinking the juice of two different citrus fruits on vascular neointima formation using a cuff-induced vascular injury mouse model. Male C57BL6 mice were divided into five groups as follows: 1) Control (water) (C), 2) 10% Citrus unshiu (CU) juice (CU10), 3) 40% CU juice (CU40), 4) 10% Citrus iyo (CI) juice (CI10), and 5) 40% CI juice (CI40). After drinking them for 2 weeks from 8 weeks of age, cuff injury was induced by polyethylene cuff placement around the femoral artery. Neointima formation was significantly attenuated in CU40, CI10 and CI40 compared with C; however, no remarkable preventive effect was observed in CU10. The increases in levels of various inflammatory markers including cytokines such as monocyte chemotactic protein-1, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α in response to vascular injury did not differ significantly between C, CU10 and CI10. The increases in cell proliferation and superoxide anion production were markedly attenuated in CI10, but not in CU10 compared with C. The increase in phosphorylated ERK expression was markedly attenuated both in CU10 and CI10 without significant difference between CU10 and CI10. Accumulation of immune cells did not differ between CU10 and CI10. These results indicate that drinking citrus fruit juice attenuates vascular remodeling partly via a reduction of oxidative stress. Interestingly, the preventive efficacy on neointima formation was stronger in CI than in CU at least in part due to more prominent inhibitory effects on oxidative stress by CI.

  18. Drinking Citrus Fruit Juice Inhibits Vascular Remodeling in Cuff-Induced Vascular Injury Mouse Model

    PubMed Central

    Ohnishi, Arika; Asayama, Rie; Mogi, Masaki; Nakaoka, Hirotomo; Kan-no, Harumi; Tsukuda, Kana; Chisaka, Toshiyuki; Wang, Xiao-Li; Bai, Hui-Yu; Shan, Bao-Shuai; Kukida, Masayoshi; Iwanami, Jun; Horiuchi, Masatsugu

    2015-01-01

    Citrus fruits are thought to have inhibitory effects on oxidative stress, thereby attenuating the onset and progression of cancer and cardiovascular disease; however, there are few reports assessing their effect on vascular remodeling. Here, we investigated the effect of drinking the juice of two different citrus fruits on vascular neointima formation using a cuff-induced vascular injury mouse model. Male C57BL6 mice were divided into five groups as follows: 1) Control (water) (C), 2) 10% Citrus unshiu (CU) juice (CU10), 3) 40% CU juice (CU40), 4) 10% Citrus iyo (CI) juice (CI10), and 5) 40% CI juice (CI40). After drinking them for 2 weeks from 8 weeks of age, cuff injury was induced by polyethylene cuff placement around the femoral artery. Neointima formation was significantly attenuated in CU40, CI10 and CI40 compared with C; however, no remarkable preventive effect was observed in CU10. The increases in levels of various inflammatory markers including cytokines such as monocyte chemotactic protein-1, interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α in response to vascular injury did not differ significantly between C, CU10 and CI10. The increases in cell proliferation and superoxide anion production were markedly attenuated in CI10, but not in CU10 compared with C. The increase in phosphorylated ERK expression was markedly attenuated both in CU10 and CI10 without significant difference between CU10 and CI10. Accumulation of immune cells did not differ between CU10 and CI10. These results indicate that drinking citrus fruit juice attenuates vascular remodeling partly via a reduction of oxidative stress. Interestingly, the preventive efficacy on neointima formation was stronger in CI than in CU at least in part due to more prominent inhibitory effects on oxidative stress by CI. PMID:25692290

  19. 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.

  20. 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.

  1. The inhibition of calpains ameliorates vascular restenosis through MMP2/TGF-β1 pathway

    PubMed Central

    Tang, Lianghu; Pei, Haifeng; Yang, Yi; Wang, Xiong; Wang, Ting; Gao, Erhe; Li, De; Yang, Yongjian; Yang, Dachun

    2016-01-01

    Restenosis limits the efficacy of vascular percutaneous intervention, in which vascular smooth muscle cell (VSMC) proliferation and activation of inflammation are two primary causal factors. Calpains influence VSMC proliferation and collagen synthesis. However, the roles of calpastatin and calpains in vascular restenosis remain unclear. Here, restenosis was induced by ligating the left carotid artery, and VSMCs were pretreated with platelet-derived growth factor (PDGF)-BB. Adenovirus vector carrying MMP2 sequence and specific small interfering RNA against calpain-1/2 were introduced. Finally, restenosis enhanced the expression of calpain-1/2, but reduced calpastatin content. In calpastatin transgenic mice, lumen narrowing was attenuated gradually and peaked on days 14–21. Cell proliferation and migration as well as collagen synthesis were inhibited in transgenic mice, and expression of calpain-1/2 and MMP2/transforming growth factor-β1 (TGF-β1). Consistently, in VSMCs pretreated with PDGF-BB, calpastatin induction and calpains inhibition suppressed the proliferation and migration of VSMCs and collagen synthesis, and reduced expression of calpain-1/2 and MMP2/TGF-β1. Moreover, simvastatin improved restenosis indicators by suppressing the HIF-1α/calpains/MMP2/TGF-β1 pathway. However, MMP2 supplementation eliminated the vascular protection of calpastatin induction and simvastatin. Collectively, calpains inhibition plays crucial roles in vascular restenosis by preventing neointimal hyperplasia at the early stage via suppression of the MMP2/TGF-β1 pathway. PMID:27453531

  2. Effects of Acute Nitric Oxide Synthase Inhibition on Lower Leg Vascular Function in Chronic Tetraplegia

    PubMed Central

    La Fountaine, Michael F; Radulovic, Miroslav; Cardozo, Christopher P; Spungen, Ann M; DeMeersman, Ronald E; Bauman, William A

    2009-01-01

    Background/Objective: To improve our understanding of the lower-leg vascular responses of nitric oxide synthase inhibition in persons with tetraplegia. Participants: Six people with chronic tetraplegia and 6 age-matched controls. Methods: Lower-leg relative vascular resistance and venous volume variation were obtained by venous occlusion plethysmography and blood pressure by auscultation at baseline. Postintravenous infusion of the nitric oxide synthase inhibitor NG-nitro-l-arginine-methyl-ester (1 mg·kg−1) or placebo on separate days. Results: At baseline in the group with tetraplegia compared with controls, mean arterial pressure and relative vascular resistance of the leg were significantly lower. After nitric oxide synthase inhibition, mean arterial pressure and lower leg vascular resistance were significantly elevated in both groups. There were no group or intervention differences in venous volume variation. Conclusion: These preliminary results suggest that nitric oxide synthase inhibition with 1 mg·kg−1 NG-nitro-l-arginine-methyl-ester normalizes seated blood pressure and lower leg vascular resistance to control group baseline levels. PMID:20025149

  3. Spinal irradiation does not inhibit distal axonal sprouting

    SciTech Connect

    Pamphlett, R.S.

    1988-05-01

    In an attempt to determine the relative importance of the nerve cell body and of the axon in initiating and controlling axonal regeneration, nerve cell bodies were irradiated and the ability of the distal axon to sprout was examined. Mice were subjected to either 25 or 50 Gray (Gy) of x-irradiation localized to the lumbar spinal cord. After times varying from 1 day to 6 months after irradiation, a sublethal dose of botulinum toxin (BoTx) was injected into the calf muscles of one leg. The soleus muscle was examined histologically after times varying from 1 week to 6 months after injection, and BoTx-induced ultraterminal axonal sprouting was assessed by the number of motor endplates showing sprouts, the length of the sprouts, and the long term endplate morphology. Apart from some irradiated subgroups having slightly shorter sprout lengths, no significant differences were found between irradiated and nonirradiated groups. The results suggest either that the processes in the nerve cell body responsible for initiating and supporting axonal growth are resistant to large doses of irradiation, or that growth regulatory mechanisms in the distal axon are under local control.

  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. Developmental inhibition of gamma irradiation on the peach fruit moth Carposina sasakii (Lepidoptera: Carposinidae)

    NASA Astrophysics Data System (ADS)

    Ryu, Jihoon; Ahn, Jun-Young; Sik Lee, Seung; Lee, Ju-Woon; Lee, Kyeong-Yeoll

    2015-01-01

    Ionizing irradiation is a useful technique for disinfestation under plant quarantine as well as post-harvest management. Effects of gamma irradiation treatment were tested on different developmental events of Carposina sasakii, which is a serious pest of various orchard crops. Apple fruits infested by C. sasakii were irradiated by gamma rays ranging from 0 to 300 Gy. Inhibition rates were determined on behavioral events related to development, including larval exit from apples, cocoon formation, adult eclosion, and oviposition. Failure rates of all these developmental events increased with increasing doses of irradiation. Rates of larval exit from apples and cocoon formation decreased to 13.2% and 1.7%, respectively, at 300 Gy. However, the adult eclosion rate decreased to 5.4% at 100 Gy and was completely inhibited at doses greater than 150 Gy. LD99 values for the inhibition of cocoon formation and adult emergence was estimated into 313.4 and 191.0 Gy. Furthermore, adults developed from irradiated larvae completely failed to lay eggs. Thus, irradiation of infested apples at doses of 200 Gy and higher completely inhibited the next generation of C. sasakii. Our results suggest that gamma irradiation treatment would be a promising technique for the control of C. sasakii.

  6. Significance of bacterial flora in abdominal irradiation-induced inhibition of lung metastases

    SciTech Connect

    Matsumoto, T.; Ando, K.; Koike, S.

    1988-06-01

    We have previously reported that abdominal irradiation prior to i.v. injection of syngeneic tumor cells reduced metastases in lung. Our report described an investigation of the significance of intestinal organisms in the radiation effect. We found that eliminating intestinal organisms with antibiotics totally abolished the radiation effect. Monoassociation of germ-free mice revealed that the radiation effect was observable only for Enterobacter cloacae, never for Streptococcus faecium, Bifidobacterium adlesentis, or Escherichia coli. After abdominal irradiation of regular mice, E. cloacae multiplied in cecal contents, adhered to mucous membranes, invaded the cecal wall, and translocated to mesenteric lymph nodes. Intravenous administration of E. cloacae in place of abdominal irradiation inhibited metastases. E. cloacae-monoassociated mice developed fewer metastases than germ-free mice, and the reduction was further enhanced by abdominal irradiation. We concluded that abdominal irradiation caused the invasion of E. cloacae from the mucous membrane of the intestine and inhibited formation of lung metastases.

  7. Microsomal Prostaglandin E Synthase-1-Derived PGE2 Inhibits Vascular Smooth Muscle Cell Calcification.

    PubMed

    Gao, Cheng; Fu, Yi; Li, Yanhui; Zhang, Xu; Zhang, Lu; Yu, Fang; Xu, Susanna S; Xu, Qingbo; Zhu, Yi; Guan, Youfei; Wang, Xian; Kong, Wei

    2016-01-01

    Chronic administration of selective cyclooxygenase-2 (COX-2) inhibitors leads to an increased risk of adverse cardiovascular events, including myocardial infarction and stroke. Vascular smooth muscle cell (VSMC) calcification, a common complication of chronic kidney disease, is directly related to cardiovascular morbidity and mortality. Here, we tested whether specific COX-2 inhibition affects vascular calcification during chronic renal failure. The COX-2-specific inhibitors NS398 and SC236 significantly increased high-phosphate (Pi)-induced VSMC calcification. Similarly, COX-2(-/-) VSMCs, COX-2(-/-) aortas rings treated with high Pi and adenine diet-induced COX-2(-/-) chronic renal failure mice displayed enhanced calcium deposition. Metabolomic analysis revealed the differential suppression of PGE2 production by COX-1- and COX-2-specific inhibitors in high-Pi-stimulated VSMCs, indicating the involvement of PGE2 during COX-2 inhibition-aggravated vascular calcification. Indeed, exogenous PGE2 reduced alkaline phosphatase activity, osteogenic transdifferentiation, apoptosis, and calcification of VSMCs. In accordance, downregulation of microsomal prostaglandin E synthase (mPGES)-1 in VSMCs, mPGES-1(-/-) aorta with high-Pi stimulation and mPGES-1(-/-) chronic renal failure mice resulted in enhanced vascular mineralization. Further applications of RNAi and specific antagonists for PGE2 receptors indicated EP4 may mediate PGE2-inhibited vascular calcification. Our data revealed the pivotal role of COX-2-mPGES-1-PGE2 axis in vascular calcification. The selective inhibition of COX-2 or mPGES-1 may increase the risk of calcification and subsequent adverse cardiovascular events during chronic renal failure. © 2015 American Heart Association, Inc.

  8. Nanoparticulate Tetrac Inhibits Growth and Vascularity of Glioblastoma Xenografts.

    PubMed

    Sudha, Thangirala; Bharali, Dhruba J; Sell, Stewart; Darwish, Noureldien H E; Davis, Paul J; Mousa, Shaker A

    2017-04-10

    Thyroid hormone as L-thyroxine (T4) stimulates proliferation of glioma cells in vitro and medical induction of hypothyroidism slows clinical growth of glioblastoma multiforme (GBM). The proliferative action of T4 on glioma cells is initiated nongenomically at a cell surface receptor for thyroid hormone on the extracellular domain of integrin αvβ3. Tetraiodothyroacetic acid (tetrac) is a thyroid hormone derivative that blocks T4 action at αvβ3 and has anticancer and anti-angiogenic activity. Tetrac has been covalently bonded via a linker to a nanoparticle (Nanotetrac, Nano-diamino-tetrac, NDAT) that increases the potency of tetrac and broadens the anticancer properties of the drug. In the present studies of human GBM xenografts in immunodeficient mice, NDAT administered daily for 10 days subcutaneously as 1 mg tetrac equivalent/kg reduced tumor xenograft weight at animal sacrifice by 50%, compared to untreated control lesions (p < 0.01). Histopathological analysis of tumors revealed a 95% loss of the vascularity of treated tumors compared to controls at 10 days (p < 0.001), without intratumoral hemorrhage. Up to 80% of tumor cells were necrotic in various microscopic fields (p < 0.001 vs. control tumors), an effect attributable to devascularization. There was substantial evidence of apoptosis in other fields (p < 0.001 vs. control tumors). Induction of apoptosis in cancer cells is a well-described quality of NDAT. In summary, systemic NDAT has been shown to be effective by multiple mechanisms in treatment of GBM xenografts.

  9. Improved hydrogen production in the microbial electrolysis cell by inhibiting methanogenesis using ultraviolet irradiation.

    PubMed

    Hou, Yanping; Luo, Haiping; Liu, Guangli; Zhang, Renduo; Li, Jiayi; Fu, Shiyu

    2014-09-02

    Methanogenesis inhibition is essential for the improvement of hydrogen (H2) yield and energy recovery in the microbial electrolysis cell (MEC). In this study, ultraviolet (UV) irradiation was proposed as an efficient method for methanogenesis control in a single chamber MEC. With 30 cycles of operation with UV irradiation in the MEC, high H2 concentrations (>91%) were maintained, while without UV irradiation, CH4 concentrations increased significantly and reached up to 94%. In the MEC, H2 yields ranged from 2.87 ± 0.03 to 3.70 ± 0.11 mol H2/mol acetate with UV irradiation and from 3.78 ± 0.12 to 0.03 ± 0.004 mol H2/mol acetate without UV irradiation. Average energy efficiencies from the UV-irradiated MEC were 1.5 times of those without UV irradiation. Energy production from the MEC without UV irradiation was a negative energy yield process because of large amount of CH4 produced over time, which was mainly attributable to cathodic hydrogenotrophic methanogenesis. Our results clearly showed that UV irradiation could effectively inhibit methanogenesis and improve MEC performance to produce H2.

  10. Cooperative effect of roscovitine and irradiation targets angiogenesis and induces vascular destabilization in human breast carcinoma.

    PubMed

    Maggiorella, L; Aubel, C; Haton, C; Milliat, F; Connault, E; Opolon, P; Deutsch, E; Bourhis, J

    2009-02-01

    Angiogenesis is considered as an essential process for tumour development and invasion. Previously, we demonstrated that cyclin-dependent kinase inhibition by roscovitine induces a radiosensitization and a synergistic antitumoral effect in human carcinoma but its effect on the microenvironment and tumour angiogenesis remains unknown. Here, we investigated the effect of the combination roscovitine and ionizing radiation (IR) on normal cells in vitro and on tumour angiogenesis in MDA-MB 231 tumour xenografts. We observed that the combination roscovitine and IR induced a marked reduction of angiogenic hot spot and microvascular density in comparison with IR or roscovitine treatments alone. The Ang-2/Tie-2 ratio was increased in presence of reduced vascular endothelial growth factor level suggesting vessel destabilization. In vitro, no radiosensitization effect of roscovitine was found in endothelial, fibroblast, and keratinocyte cells. IR potentiated the antiproliferative effect of roscovitine without inducing apoptosis in endothelial cells. Roscovitine decreased IR-stimulated vascular endothelial growth factor secretion of MDA-MB 231 and endothelial cells. A reduction in the endothelial cells invasion and the capillary-like tube formation in Matrigel were observed following the combination roscovitine and IR. This combined treatment targets angiogenesis resulting in microvessel destabilization without inducing normal cell toxicity.

  11. 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.

  12. Inhibition of recovery of spermatogenesis in irradiated rats by different androgens.

    PubMed

    Shetty, Gunapala; Wilson, Gene; Hardy, Matthew P; Niu, Enmei; Huhtaniemi, Ilpo; Meistrich, Marvin L

    2002-09-01

    We previously showed that exogenous testosterone (T) inhibited GnRH-antagonist-stimulated spermatogenic recovery in irradiated rats through an androgen-receptor-mediated action. In the present study, we tested whether the inhibition is attributable to T, a specific androgenic metabolite of T, or a general property of androgens in this system. In addition, we also tested whether estradiol-17beta (E2), a metabolite of T, is similarly inhibitory. Rats irradiated with 5 Gy were treated with a GnRH antagonist during wk 3-7. Neither irradiation nor GnRH-antagonist treatment produced biologically significant changes in the relative intratesticular levels of several androgenic metabolites. Next, groups of rats, irradiated and treated with GnRH antagonist as above, were given various doses of one of the following androgens: T, 5alpha-dihydrotestosterone, 7alpha-methyl-19-nortestosterone, methyltrienolone, or E2. The percentage of tubules showing differentiation (tubule differentiation index) was increased to 68% by the GnRH antagonist, from a value of 0.1% in irradiated-only rats at 13 wk after irradiation. All of the added androgens inhibited spermatogenic recovery, lowering the tubule differentiation index to between 0.4-36%, but no inhibition was observed with the addition of E2. Of all the androgen treatments tested, T (given as daily injections of T propionate) minimally inhibited spermatogenic recovery while maintaining androgen-responsive tissue weights, and might be most useful in clinical studies. Hormonal measurements in androgen-treated rats were most consistent with the androgen inhibition of spermatogenic recovery in irradiated rats being a combined result of a direct inhibitory effect of all androgens on the testis and an indirect effect through the pituitary by raising levels of FSH, which seems to add to the inhibition of spermatogenic recovery.

  13. Dll4 activation of Notch signaling reduces tumor vascularity and inhibits tumor growth

    PubMed Central

    Williams, Cassin Kimmel; la Luz Sierra, Maria de; Bernardo, Marcelino; McCormick, Peter J.; Maric, Dragan; Regino, Celeste; Choyke, Peter; Tosato, Giovanna

    2008-01-01

    Gene targeting experiments have shown that Delta-like 4 (Dll4) is a vascular-specific Notch ligand critical to normal vascular development. Recent studies have demonstrated that inhibition of Dll4/Notch signaling in tumor-bearing mice resulted in excessive, yet nonproductive tumor neovascularization and unexpectedly reduced tumor growth. Because nonfunctional blood vessels have the potential to normalize, we explored the alternative approach of stimulating Notch signaling in the tumor vasculature to inhibit tumor growth. Here we show that retrovirus-induced over-expression of Dll4 in tumor cells activates Notch signaling in cocultured endothelial cells and limits vascular endothelial growth factor (VEGF)–induced endothelial cell growth. Tumors produced in mice by injection of human and murine tumor cells transduced with Dll4 were significantly smaller, less vascularized and more hypoxic than controls, and displayed evidence of Notch activation. In addition, tumor blood perfusion was reduced as documented by vascular imaging. These results demonstrate that Notch activation in the tumor microenvironment reduces tumor neovascularization and blood perfusion, and suggest that Dll4-induced Notch activation may represent an effective therapeutic approach for the treatment of solid tumors. PMID:18577711

  14. Statins inhibited erythropoietin-induced proliferation of rat vascular smooth muscle cells.

    PubMed

    Kaneda, Tae; Tsuruoka, Shuichi; Fujimura, Akio

    2010-12-15

    Erythropoietin (EPO) directly stimulates the proliferation of vascular smooth muscle cells, and this is believed to be one of the mechanisms of vascular access failure of hemodialysis patients. However, precise mechanisms of the EPO-induced proliferation of vascular smooth muscle cells are not certain. HMG-CoA reductase inhibitors (statins) are primarily used to reduce cholesterol levels, but also exert other effects, including reno-protective effects. We evaluated the effect of several statins with various hydrophilicities on the EPO-induced proliferation of primary cultured rat vascular smooth muscle cells (VSMCs) in vitro. EPO significantly and concentration-dependently increased DNA synthesis as assessed by [³H]thymidine incorporation, cell proliferation as assessed by WST-1 assay, and activation of the p44/42MAPK pathway. Therapeutic doses of statins (pravastatin, simvastatin, atorvastatin and fluvastatin) in patients with hypercholesterolemia almost completely suppressed all of the EPO-induced effects in a concentration-dependent manner. Co-addition of mevalonic acid almost completely reversed the effects of statins. Statin alone did not affect the basal proliferation capacity of the cells. The effects were almost similar among the statins. We concluded that statins inhibited EPO-induced proliferation in rat VSMCs at least partly through their inhibition of HMG-CoA reductase activity. In the future, statins might prove useful for the treatment of EPO-induced hyperplasia of vascular access. Because the statins all showed comparable effects irrespective of their hydrophilicities, these effects might be a class effect.

  15. Inhibition of angiopoietin-1 (ANGPT1) affects vascular integrity in ovarian hyperstimulation syndrome (OHSS).

    PubMed

    Scotti, Leopoldina; Abramovich, Dalhia; Pascuali, Natalia; Durand, Luis Haro; Irusta, Griselda; de Zúñiga, Ignacio; Tesone, Marta; Parborell, Fernanda

    2016-04-01

    Ovarian hyperstimulation syndrome (OHSS) is a complication of ovarian stimulation with gonadotrophins following human chorionic gonadotrophin (hCG) administration. The relationship between hCG and OHSS is partly mediated via the production of angiogenic factors, such as vascular endothelial growth factor A (VEGFA) and angiopoietins (ANGPTs). Here, we investigated the effect of ANGPT1 inhibition on ovarian angiogenesis in follicular fluid (FF) from women at risk of OHSS, using the chorioallantoic membrane (CAM) of quail embryos as an experimental model. We also analysed cytoskeletal changes and endothelial junction protein expression induced by this FF in the presence or absence of an ANGPT1-neutralising antibody in endothelial cell cultures. The presence of this antibody restored the number of vascular branch points and integrin αvβ3 levels in the CAMs to control values. ANGPT1 inhibition in FF from OHSS patients also restored the levels of claudin-5, vascular endothelial cadherin and phosphorylated β-catenin and partially reversed actin redistribution in endothelial cells. Our findings suggest that ANGPT1 increases pathophysiological angiogenesis in patients at risk of OHSS by acting on tight and adherens junction proteins. Elucidating the mechanisms by which ANGPT1 regulates vascular development and cell-cell junctions in OHSS will contribute to identifying new therapeutic targets for the treatment of human diseases with aberrant vascular leakage.

  16. Inability of donor total body irradiation to prolong survival of vascularized bone allografts: Experimental study in the rat

    SciTech Connect

    Gonzalez del Pino, J.; Benito, M.; Randolph, M.A.; Weiland, A.J. )

    1990-07-01

    At the present time, the toxic side effects of recipient immunosuppression cannot be justified for human non-vital organ transplantation. Total body irradiation has proven effective in ablating various bone-marrow-derived and endothelial immunocompetent cellular populations, which are responsible for immune rejection against donor tissues. Irradiation at a dose of 10 Gy was given to donor rats six days prior to heterotopic transplantation of vascularized bone allografts to host animals. Another group of recipient rats also received a short-term (sixth to fourteenth day after grafting), low dose of cyclosporine. Total body irradiation was able merely to delay rejection of grafts across a strong histocompatibility barrier for one to two weeks, when compared to nonirradiated allografts. The combination of donor irradiation plus cyclosporine did not delay the immune response, and the rejection score was similar to that observed for control allografts. Consequently, allograft viability was quickly impaired, leading to irreversible bone damage. This study suggest that 10 Gy of donor total body irradiation delivered six days prior to grafting cannot circumvent the immune rejection in a vascularized allograft of bone across a strong histocompatibility barrier.

  17. Irradiation selectively inhibits expression from the androgen-dependent Pem homeobox gene promoter in sertoli cells.

    PubMed

    Maiti, S; Meistrich, M L; Wilson, G; Shetty, G; Marcelli, M; McPhaul, M J; Morris, P L; Wilkinson, M F

    2001-04-01

    How radiation blocks spermatogenesis in certain strains of rats, such as LBNF(1), is not known. Because the block depends on androgen, we propose that androgen affects Sertoli cell function in irradiated LBNF(1) rats, resulting in the failure of spermatogonial differentiation. To begin to identify genes that may participate in this irradiation-induced blockade of spermatogenesis, we investigated the expression of several Sertoli genes in response to irradiation. The expression of the PEM: homeobox gene from its androgen-dependent Sertoli-specific proximal promoter (Pp) was dramatically reduced more than 100-fold in response to irradiation. In contrast, most other genes and gene products reported to be localized to the Sertoli cell, including FSH receptor (FSHR), androgen receptor (AR), SGP1, and the transcription factor CREB, did not exhibit significant changes in expression, whereas transferrin messenger RNA (mRNA) expression dramatically increased in response to irradiation. Irradiation also decreased Pp-driven PEM: mRNA levels in mouse testes (approximately 10-fold), although higher doses of irradiation than in rats were required to inhibit PEM: gene expression in testes of mice, consistent with their greater radioresistance. The decrease in Pem gene expression in mouse testis was also selective, as the expression of CREB, GATA-1, and SGP1 were little affected by irradiation. We conclude that the dramatic irradiation-triggered reduction of Pem expression in Sertoli cells is a conserved response that may be a marker for functional changes in response to irradiation.

  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. Inhibition of Smooth Muscle β-Catenin Hinders Neointima Formation After Vascular Injury.

    PubMed

    Riascos-Bernal, Dario F; Chinnasamy, Prameladevi; Gross, Jordana N; Almonte, Vanessa; Egaña-Gorroño, Lander; Parikh, Dippal; Jayakumar, Smitha; Guo, Liang; Sibinga, Nicholas E S

    2017-05-01

    Smooth muscle cells (SMCs) contribute to neointima formation after vascular injury. Although β-catenin expression is induced after injury, whether its function is essential in SMCs for neointimal growth is unknown. Moreover, although inhibitors of β-catenin have been developed, their effects on SMC growth have not been tested. We assessed the requirement for SMC β-catenin in short-term vascular homeostasis and in response to arterial injury and investigated the effects of β-catenin inhibitors on vascular SMC growth. We used an inducible, conditional genetic deletion of β-catenin in SMCs of adult mice. Uninjured arteries from adult mice lacking SMC β-catenin were indistinguishable from controls in terms of structure and SMC marker gene expression. After carotid artery ligation, however, vessels from mice lacking SMC β-catenin developed smaller neointimas, with lower neointimal cell proliferation and increased apoptosis. SMCs lacking β-catenin showed decreased mRNA expression of Mmp2, Mmp9, Sphk1, and S1pr1 (genes that promote neointima formation), higher levels of Jag1 and Gja1 (genes that inhibit neointima formation), decreased Mmp2 protein expression and secretion, and reduced cell invasion in vitro. Moreover, β-catenin inhibitors PKF118-310 and ICG-001 limited growth of mouse and human vascular SMCs in a dose-dependent manner. SMC β-catenin is dispensable for maintenance of the structure and state of differentiation of uninjured adult arteries, but is required for neointima formation after vascular injury. Pharmacological β-catenin inhibitors hinder growth of human vascular SMCs. Thus, inhibiting β-catenin has potential as a therapy to limit SMC accumulation and vascular obstruction. © 2017 American Heart Association, Inc.

  20. Inhibition of Epac1 suppresses mitochondrial fission and reduces neointima formation induced by vascular injury

    PubMed Central

    Wang, Hui; Robichaux, William G.; Wang, Ziqing; Mei, Fang C.; Cai, Ming; Du, Guangwei; Chen, Ju; Cheng, Xiaodong

    2016-01-01

    Vascular smooth muscle cell (VSMC) activation in response to injury plays an important role in the development of vascular proliferative diseases, including restenosis and atherosclerosis. The aims of this study were to ascertain the physiological functions of exchange proteins directly activated by cAMP isoform 1 (Epac1) in VSMC and to evaluate the potential of Epac1 as therapeutic targets for neointima formation during vascular remodeling. In a mouse carotid artery ligation model, genetic knockdown of the Epac1 gene led to a significant reduction in neointima obstruction in response to vascular injury. Pharmacologic inhibition of Epac1 with an Epac specific inhibitor, ESI-09, phenocopied the effects of Epac1 null by suppressing neointima formation and proliferative VSMC accumulation in neointima area. Mechanistically, Epac1 deficient VSMCs exhibited lower level of PI3K/AKT signaling and dampened response to PDGF-induced mitochondrial fission and reactive oxygen species levels. Our studies indicate that Epac1 plays important roles in promoting VSMC proliferation and phenotypic switch in response to vascular injury, therefore, representing a therapeutic target for vascular proliferative diseases. PMID:27830723

  1. Magnolol inhibits migration of vascular smooth muscle cells via cytoskeletal remodeling pathway to attenuate neointima formation

    SciTech Connect

    Karki, Rajendra; Kim, Seong-Bin; Kim, Dong-Wook

    2013-12-10

    Background: Increased proliferation and migration of vascular smooth muscle cells (VSMCs) contribute importantly to the formation of both atherosclerotic and restenotic lesions. The objective of this study was to investigate the effect of magnolol on VSMC migration. Methods: The proteolytic activity of matrix metalloproteinases (MMPs) in tumor necrosis factor alpha (TNF-α) stimulated VSMCs was performed by gelatin zymography. VSMC migration was assessed by wound healing and Boyden chamber methods. Collagen induced VSMC adhesion was determined by spectrofluorimeter and stress fibers formation was evaluated by fluorescence microscope. The expression of signaling molecules involved in stress fibers formation was determined by western blot. The phosphorylation of myosin light chain (MLC20) was determined by urea-glycerol polyacrylamide gel electrophoresis. Immunohistochemistry was performed to determine the expression of β1-integrin and collagen type I in the injured carotid arteries of rats on day 35 after vascular injury. Results: VSMC migration was strongly inhibited by magnolol without affecting MMPs expression. Also, magnolol inhibited β1-integrin expression, FAK phosphorylation and RhoA and Cdc42 activation to inhibit the collagen induced stress fibers formation. Moreover, magnolol inhibited the phosphorylation of MLC20. Our in vivo results showed that magnolol inhibited β1-integrin expression, collagen type I deposition and FAK phosphorylation in injured carotid arteries without affecting MMP-2 activity. Conclusions: Magnolol inhibited VSMC migration via inhibition of cytoskeletal remodeling pathway to attenuate neointima formation. General significance: This study provides a rationale for further evaluation of magnolol for the management of atherosclerosis and restenosis. - Highlights: • Magnolol strongly inhibited migration of VSMCs. • Magnolol inhibited stress fibers formation. • MLC20 phosphorylation was also inhibited by magnolol. • Anti

  2. Carboxylated nanodiamonds inhibit γ-irradiation damage of human red blood cells

    NASA Astrophysics Data System (ADS)

    Santacruz-Gomez, K.; Silva-Campa, E.; Melendrez-Amavizca, R.; Teran Arce, F.; Mata-Haro, V.; Landon, P. B.; Zhang, C.; Pedroza-Montero, M.; Lal, R.

    2016-03-01

    Nanodiamonds when carboxylated (cNDs) act as reducing agents and hence could limit oxidative damage in biological systems. Gamma (γ)-irradiation of whole blood or its components is required in immunocompetent patients to prevent transfusion-associated graft versus host disease (TA-GVHD). However, γ-irradiation of blood also deoxygenates red blood cells (RBCs) and induces oxidative damage, including abnormalities in cellular membranes and hemolysis. Using atomic force microscopy (AFM) and Raman spectroscopy, we examined the effect of cNDs on γ-irradiation mediated deoxygenation and morphological damage of RBCs. γ-Radiation induced several morphological phenotypes, including stomatocytes, codocytes and echinocytes. While stomatocytes and codocytes are reversibly damaged RBCs, echinocytes are irreversibly damaged. AFM images show significantly fewer echinocytes among cND-treated γ-irradiated RBCs. The Raman spectra of γ-irradiated RBCs had more oxygenated hemoglobin patterns when cND-treated, resembling those of normal, non-irradiated RBCs, compared to the non-cND-treated RBCs. cND inhibited hemoglobin deoxygenation and morphological damage, possibly by neutralizing the free radicals generated during γ-irradiation. Thus cNDs have the therapeutic potential to preserve the quality of stored blood following γ-irradiation.Nanodiamonds when carboxylated (cNDs) act as reducing agents and hence could limit oxidative damage in biological systems. Gamma (γ)-irradiation of whole blood or its components is required in immunocompetent patients to prevent transfusion-associated graft versus host disease (TA-GVHD). However, γ-irradiation of blood also deoxygenates red blood cells (RBCs) and induces oxidative damage, including abnormalities in cellular membranes and hemolysis. Using atomic force microscopy (AFM) and Raman spectroscopy, we examined the effect of cNDs on γ-irradiation mediated deoxygenation and morphological damage of RBCs. γ-Radiation induced several

  3. Monocyte-expressed urokinase inhibits vascular smooth muscle cell growth by activating Stat1.

    PubMed

    Kunigal, Sateesh; Kusch, Angelika; Tkachuk, Natalia; Tkachuk, Sergey; Jerke, Uwe; Haller, Hermann; Dumler, Inna

    2003-12-15

    After vascular injury, a remodeling process occurs that features leukocyte migration and infiltration. Loss of endothelial integrity allows the leukocytes to interact with vascular smooth muscle cells (VSMCs) and to elicit "marching orders"; however, the signaling processes are poorly understood. We found that human monocytes inhibit VSMC proliferation and induce a migratory potential. The monocytes signal the VSMCs through the urokinase-type plasminogen activator (uPA). The VSMC uPA receptor (uPAR) receives the signal and activates the transcription factor Stat1 that, in turn, mediates the antiproliferative effects. These results provide the first evidence that monocytes signal VSMCs by mechanisms involving the fibrinolytic system, and they imply an important link between the uPA/uPAR-related signaling machinery and human vascular disease.

  4. Genetic and Pharmacologic Inhibition of the Chemokine Receptor CXCR2 Prevents Experimental Hypertension and Vascular Dysfunction

    PubMed Central

    Wang, Lei; Zhao, Xue-Chen; Cui, Wei; Ma, Yong-Qiang; Ren, Hua-Liang; Zhou, Xin; Fassett, John; Yang, Yan-Zong; Chen, Yingjie; Xia, Yun-Long; Du, Jie

    2016-01-01

    Background: The recruitment of leukocytes to the vascular wall is a key step in hypertension development. Chemokine receptor CXCR2 mediates inflammatory cell chemotaxis in several diseases. However, the role of CXCR2 in hypertension development and the underlying mechanisms remain unknown. Methods: Angiotensin II (490 ng·kg-1·min-1) or deoxycorticosterone acetate (DOCA) salt–induced mouse hypertensive models in genetic ablation, pharmacologic inhibition of CXCR2, and adoptive bone marrow transfer mice were used to determine the role of CXCR2 in hypertension (measured by radiotelemetry and tail-cuff system), inflammation (verified by flow cytometry and quantitative real-time polymerase chain reaction [PCR] analysis), vascular remodeling (studied by haematoxylin and eosin and Masson’s trichrome staining), vascular dysfunction (assessed by aortic ring), and oxidative stress (indicated by nicotinamide adenine dinucleotide phosphate [NADPH] oxidase activity, dihydroethidium staining, and quantitative real-time PCR analysis). Moreover, the blood CXCR2+ cells in normotensive controls and hypertension patients were analyzed by flow cytometry. Results: Angiotensin II significantly upregulated the expression of CXCR2 mRNA and protein and increased the number of CD45+ CXCR2+ cells in mouse aorta (n=8 per group). Selective CXCR2 knockout (CXCR2-/-) or pharmacological inhibition of CXCR2 markedly reduced angiotensin II- or DOCA-salt-induced blood pressure elevation, aortic thickness and collagen deposition, accumulation of proinflammatory cells into the vascular wall, and expression of cytokines (n=8 per group). CXCR2 inhibition also ameliorated angiotensin II-induced vascular dysfunction and reduced vascular superoxide formation, NADPH activity, and expression of NADPH oxidase subunits (n=6 per group). Bone marrow reconstitution of wild-type mice with CXCR2-/- bone marrow cells also significantly abolished angiotensin II-induced responses (n=6 per group). It is important

  5. 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

  6. Effects of inhibition of urokinase-type plasminogen activator (u-PA) by amiloride in the cornea and tear fluid of eyes irradiated with UVB.

    PubMed

    Cejková, J; Cejka, C; Zvárová, J

    2005-01-01

    The purpose of the present study was to test our hypothesis that amiloride, a specific u-PA inhibitor, effectively decreases u-PA activity in cornea as well as in tear fluid and favourably affects corneal healing. Therefore, comparative histochemical and biochemical studies of u-PA and the effects of amiloride were performed on rabbit corneas and tear fluid using the sensitive fluorogenic substrate Z-Gly-Gly-Arg-7-amino-4-trifluoromethylcoumarin. Rabbit eyes were repeatedly irradiated with UVB for 9 days and during the irradiation topically treated with amiloride (1 mg/ml saline) or placebo (saline) (dropwise, 5 times daily). Results show that in placebo-treated eyes, UVB evoked the appearance of u-PA activity in cornea and tear fluid in early stages of irradiation, and u-PA levels increased during irradiation. Corneal epithelium was gradually lost and remnants of the epithelium as well as keratocytes in the upper part of corneal stroma showed high u-PA activity. Finally, corneas lost their epithelium completely. In corneal stroma, numerous u-PA-containing inflammatory cells were present. Corneas were vascularized. When amiloride was dropped on the eye surface on the first day of irradiation and subsequently daily until the end of the experiment, u-PA activity in both cornea and tear fluid was strongly inhibited. Corneas were covered with a continuous epithelium until the end of the experiment. The number of inflammatory cells was significantly decreased. Corneal vascularization was reduced by 50%. In conclusion, early application of amiloride inhibited u-PA activity in UVB-irradiated corneas as well as in tear fluid and diminished the development of corneal pathology.

  7. 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

  8. 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

  9. Dehydroleucodine inhibits vascular smooth muscle cell proliferation in G2 phase.

    PubMed

    Cruzado, M; Castro, C; Fernandez, D; Gomez, L; Roque, M; Giordano, O E; Lopez, L A

    2005-11-08

    Vascular smooth muscle cell (VSMC) proliferation plays an important role in the development of atherosclerosis and in the vascular changes seen in hypertension. Dehydroleucodine (DhL) is a sesquiterpene lactone that inhibits cell proliferation in plant cells. In this paper, we study the effect of DhL in the proliferation of VSMCs stimulated with 10% fetal bovine serum (FBS). Very low concentrations of DhL (2-6 microM) inhibited VSMC proliferation and induced cell accumulation in G2. DhL did not affect the dynamics of 3H-thymidine incorporation, and did not modify either the activity of DNA polymerase or the incorporation of deoxyribonucleotides in an in vitro assay. Moreover, DhL did not induce apoptosis in VSMCs. These results indicate that DhL, in very low concentration, induces a transient arrest of VSMCs in G2. Our data show that VSMCs are especially sensitive to DhL effect, suggesting that DhL could be potentially useful to prevent the vascular pathological changes seen in hypertension and other vascular diseases.

  10. COX-2 inhibition and hypoxia-induced pulmonary hypertension: effects on pulmonary vascular remodeling and contractility

    PubMed Central

    Fredenburgh, Laura E.; Ma, Jun; Perrella, Mark A.

    2009-01-01

    Pulmonary arterial hypertension (PAH) is a significant disease process characterized by elevated pulmonary vascular resistance leading to increased right ventricular afterload and ultimately progressing to right ventricular dysfunction and often death. Irreversible remodeling of the pulmonary vasculature is the hallmark of pulmonary hypertension and frequently leads to progressive functional decline in patients with PAH despite treatment with currently available therapies. Metabolites of the arachidonic acid cascade play an important homeostatic role in the pulmonary vasculature and dysregulation of pathways downstream of arachidonic acid play a central role in the pathobiology of PAH. Cyclooxygenase-2 (COX-2) is upregulated in pulmonary artery smooth muscle cells (PASMC) and inflammatory cells during hypoxia and plays a protective role in the lung’s response to hypoxia. We recently demonstrated that absence of COX-2 was detrimental in a mouse model of hypoxia-induced pulmonary hypertension. Exposure of COX-2 null mice to hypoxia resulted in severe pulmonary hypertension characterized by enhanced pulmonary vascular remodeling and significant upregulation of the ET-1 receptor (ETAR) in the lung following hypoxia. Absence of COX-2 in vitro led to enhanced contractility of PASMC following exposure to hypoxia that could be attenuated by iloprost, a prostaglandin I2 analog. These findings suggest that selective inhibition of COX-2 may have detrimental pulmonary vascular consequences in patients with pre-existing pulmonary hypertension or underlying hypoxemic lung diseases. Here we discuss our recent data demonstrating the adverse consequences of COX-2 inhibition on pulmonary vascular remodeling and PASMC contractility. PMID:19577709

  11. 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

  12. Vascular expression of the chemokine CX3CL1 promotes osteoclast recruitment and exacerbates bone resorption in an irradiated murine model.

    PubMed

    Han, Ki Hoon; Ryu, Jae Won; Lim, Kyung-Eun; Lee, Soo-Han; Kim, Yuna; Hwang, Chang Sun; Choi, Je-Yong; Han, Ki Ok

    2014-04-01

    Circulating osteoclast precursor cells highly express CX3C chemokine receptor 1 (CX3CR1), which is the only receptor for the unique CX3C membrane-anchored chemokine, fractalkine (CX3CL1). An irradiated murine model was used to evaluate the role of the CX3CL1-CX3CR1 axis in osteoclast recruitment and osteoclastogenesis. Ionizing radiation (IR) promoted the migration of circulating CD11b+ cells to irradiated bones and dose-dependently increased the number of differentiated osteoclasts in irradiated bones. Notably, CX3CL1 was dramatically upregulated in the vascular endothelium after IR. IR-induced production of CX3CL1 by skeletal vascular endothelium promoted chemoattraction of circulating CX3CR1+/CD11b+ cells and triggered homing of these osteoclast precursor cells toward the bone remodeling surface, a specific site for osteoclast differentiation. CX3CL1 also increased the endothelium-derived expression of other chemokines including stromal cell-derived factor-1 (CXCL12) and macrophage inflammatory protein-2 (CXCL2) by activating the hypoxia-inducible factor-1 α pathway. These effects may further enhance osteoclastogenesis. A series of in vivo experiments confirmed that knockout of CX3CR1 in bone marrow-derived cells and functional inhibition of CX3CL1 using a specific neutralizing antibody significantly ameliorated osteoclastogenesis and prevented bone loss after IR. These results demonstrate that the de novo CX3CL1-CX3CR1 axis plays a pivotal role in osteoclast recruitment and subsequent bone resorption, and verify its therapeutic potential as a new target for anti-resorptive treatment.

  13. Hydrogen Sulfide Improves Vascular Calcification in Rats by Inhibiting Endoplasmic Reticulum Stress

    PubMed Central

    Yang, Rui; Teng, Xu; Li, Hui; Xue, Hong-Mei; Guo, Qi; Xiao, Lin; Wu, Yu-Ming

    2016-01-01

    In this study, the vitamin D3 plus nicotine (VDN) model of rats was used to prove that H2S alleviates vascular calcification (VC) and phenotype transformation of vascular smooth muscle cells (VSMC). Besides, H2S can also inhibit endoplasmic reticulum stress (ERS) of calcified aortic tissues. The effect of H2S on alleviating VC and phenotype transformation of VSMC can be blocked by TM, while PBA also alleviated VC and phenotype transformation of VSMC that was similar to the effect of H2S. These results suggest that H2S may alleviate rat aorta VC by inhibiting ERS, providing new target and perspective for prevention and treatment of VC. PMID:27022436

  14. Hydrogen Sulfide Improves Vascular Calcification in Rats by Inhibiting Endoplasmic Reticulum Stress.

    PubMed

    Yang, Rui; Teng, Xu; Li, Hui; Xue, Hong-Mei; Guo, Qi; Xiao, Lin; Wu, Yu-Ming

    2016-01-01

    In this study, the vitamin D3 plus nicotine (VDN) model of rats was used to prove that H2S alleviates vascular calcification (VC) and phenotype transformation of vascular smooth muscle cells (VSMC). Besides, H2S can also inhibit endoplasmic reticulum stress (ERS) of calcified aortic tissues. The effect of H2S on alleviating VC and phenotype transformation of VSMC can be blocked by TM, while PBA also alleviated VC and phenotype transformation of VSMC that was similar to the effect of H2S. These results suggest that H2S may alleviate rat aorta VC by inhibiting ERS, providing new target and perspective for prevention and treatment of VC.

  15. Combining hedgehog signaling inhibition with focal irradiation on reduction of pancreatic cancer metastasis

    PubMed Central

    Gu, Dongsheng; Liu, Hailan; Su, Gloria H.; Zhang, Xiaoli; Chin-Sinex, Helen; Hanenberg, Helmut; Mendonca, Marc S.; Shannon, Harlan E.; Chiorean, E. Gabriela; Xie, Jingwu

    2013-01-01

    Pancreatic cancer often presents in advanced stages and is unresponsive to conventional treatments. Thus, the need to develop novel treatment strategies for pancreatic cancer has never been greater. Here we report that combination of focal irradiation with hedgehog (Hh) signaling inhibition exerts better than additive effects on reducing metastases. In an orthotopic model, we found that focal irradiation alone effectively reduced primary tumor growth but did not significantly affect metastasis. We hypothesized that cancer stem cells (CSC) of pancreatic cancer are responsible for the residual tumors following irradiation, which may be regulated by Hh signaling. To test our hypothesis, we showed that tumor metastasis in our model was accompanied by increased expression of CSC cell surface markers as well as Hh target genes. We generated tumor spheres from orthotopic pancreatic and metastatic tumors, which have elevated levels of CSC markers relative to the parental cells and elevated expression of Hh target genes. Irradiation of tumor spheres further elevated CSC cell surface markers and increased Hh target gene expression. Combination of Hh signaling inhibition with radiation had more than additive effects on tumor sphere regeneration in vitro. This phenotype was observed in two independent cell lines. In our orthotopic animal model, focal radiation plus Hh inhibition had more than additive effects on reducing lymph node metastasis. We identified several potential molecules in mediating Hh signaling effects. Taken together, our data provide a rationale for combined use of Hh inhibition with irradiation for clinical treatment of pancreatic cancer patients. PMID:23468532

  16. Combining hedgehog signaling inhibition with focal irradiation on reduction of pancreatic cancer metastasis.

    PubMed

    Gu, Dongsheng; Liu, Hailan; Su, Gloria H; Zhang, Xiaoli; Chin-Sinex, Helen; Hanenberg, Helmut; Mendonca, Marc S; Shannon, Harlan E; Chiorean, E Gabriela; Xie, Jingwu

    2013-06-01

    Pancreatic cancer often presents in advanced stages and is unresponsive to conventional treatments. Thus, the need to develop novel treatment strategies for pancreatic cancer has never been greater. Here, we report that combination of focal irradiation with hedgehog (Hh) signaling inhibition exerts better than additive effects on reducing metastases. In an orthotopic model, we found that focal irradiation alone effectively reduced primary tumor growth but did not significantly affect metastasis. We hypothesized that cancer stem cells (CSC) of pancreatic cancer are responsible for the residual tumors following irradiation, which may be regulated by Hh signaling. To test our hypothesis, we showed that tumor metastasis in our model was accompanied by increased expression of CSC cell surface markers as well as Hh target genes. We generated tumor spheres from orthotopic pancreatic and metastatic tumors, which have elevated levels of CSC markers relative to the parental cells and elevated expression of Hh target genes. Irradiation of tumor spheres further elevated CSC cell surface markers and increased Hh target gene expression. Combination of Hh signaling inhibition with radiation had more than additive effects on tumor sphere regeneration in vitro. This phenotype was observed in two independent cell lines. In our orthotopic animal model, focal radiation plus Hh inhibition had more than additive effects on reducing lymph node metastasis. We identified several potential molecules in mediating Hh signaling effects. Taken together, our data provide a rationale for combined use of Hh inhibition with irradiation for clinical treatment of patients with pancreatic cancer.

  17. Soluble Epoxide Hydrolase Inhibition and Epoxyeicosatrienoic Acid Treatment Improve Vascularization of Engineered Skin Substitutes

    PubMed Central

    Hahn, Jennifer M.; McFarland, Kevin L.; Combs, Kelly A.; Lee, Kin Sing Stephen; Inceoglu, Bora; Wan, Debin; Boyce, Steven T.; Hammock, Bruce D.

    2016-01-01

    Background: Autologous engineered skin substitutes comprised of keratinocytes, fibroblasts, and biopolymers can serve as an adjunctive treatment for excised burns. However, engineered skin lacks a vascular plexus at the time of grafting, leading to slower vascularization and reduced rates of engraftment compared with autograft. Hypothetically, vascularization of engineered skin grafts can be improved by treatment with proangiogenic agents at the time of grafting. Epoxyeicosatrienoic acids (EETs) are cytochrome P450 metabolites of arachidonic acid that are inactivated by soluble epoxide hydrolase (sEH). EETs have multiple biological activities and have been shown to promote angiogenesis. Inhibitors of sEH (sEHIs) represent attractive therapeutic agents because they increase endogenous EET levels. We investigated sEHI administration, alone or combined with EET treatment, for improved vascularization of engineered skin after grafting to mice. Methods: Engineered skin substitutes, prepared using primary human fibroblasts and keratinocytes, were grafted to full-thickness surgical wounds in immunodeficient mice. Mice were treated with the sEHI 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), which was administered in drinking water throughout the study period, with or without topical EET treatment, and were compared with vehicle-treated controls. Vascularization was quantified by image analysis of CD31-positive areas in tissue sections. Results: At 2 weeks after grafting, significantly increased vascularization was observed in the TPPU and TPPU + EET groups compared with controls, with no evidence of toxicity. Conclusions: The results suggest that sEH inhibition can increase vascularization of engineered skin grafts after transplantation, which may contribute to enhanced engraftment and improved treatment of full-thickness wounds. PMID:28293507

  18. Inhibition of TLR4 attenuates vascular dysfunction and oxidative stress in diabetic rats.

    PubMed

    Carrillo-Sepulveda, Maria Alicia; Spitler, Kathryn; Pandey, Deepesh; Berkowitz, Dan E; Matsumoto, Takayuki

    2015-12-01

    Hyperglycemia-induced reactive oxygen species (ROS) production plays a major role in the pathogenesis of diabetic vascular dysfunction. However, the underlying mechanisms remain unclear. Toll-like receptor 4 (TLR4), a key component of innate immunity, is known to be activated during diabetes. Therefore, we hypothesize that hyperglycemia activates TLR4 signaling in vascular smooth muscle cells (VSMCs) that triggers ROS production and causes vascular dysfunction. Rat mesenteric VSMCs exposed to high glucose (25 mmol/l) increased TLR4 expression and activated TLR4 signaling via upregulation of myeloid differentiation factor 88 (MyD88). TLR4 inhibitor CLI-095 significantly attenuated elevated levels of ROS and nuclear factor-kappa B (NF-κB) activity in VSMCs exposed to high glucose. Mesenteric arteries from streptozotocin-induced diabetic rats treated with CLI-095 (2 mg/kg/day) intraperitoneally for 2 weeks exhibited reduced ROS generation and attenuated noradrenaline-induced contraction. These results suggest that hyperglycemia-induced ROS generation and NF-κB activation in VSMCs are at least, in part, mediated by TLR4 signaling. Therefore, strategies to block TLR4 signaling pathways pose a promising avenue to alleviate diabetic-induced vascular complications. High glucose-induced TLR4 activation in vascular smooth muscle cells. Inhibition of TLR4 attenuated high glucose-induced ROS production and NF-κB activity in VSMC. Suppression of TLR4 signaling attenuated mesenteric contraction in diabetic rat.

  19. Microtubule stabilization attenuates vascular calcification through the inhibition of osteogenic signaling and matrix vesicle release.

    PubMed

    Lee, Kyunghee; Kim, Hyunsoo; Jeong, Daewon

    2014-08-29

    Vascular calcification is a strong predictor of cardiovascular morbidity and mortality, especially in individuals with chronic kidney disease or diabetes. The mechanism of vascular calcification has remained unclear, however, and no effective therapy is currently available. Our study was aimed at identifying the role of dynamic remodeling of microtubule cytoskeletons in hyperphosphatemia-induced vascular calcification. Exposure of primary cultures of mouse vascular smooth muscle cells (VSMCs) to inorganic phosphate (Pi) elicited ectopic calcification that was associated with changes in tubulin dynamics, induction of osteogenic signaling, and increased release of matrix vesicles. A microtubule depolymerizing agent enhanced Pi-dependent calcification, whereas microtubule stabilization by paclitaxel suppressed calcification both in VSMC cultures and in an ex vivo culture system for the mouse aorta. The inhibition of Pi-stimulated calcification by paclitaxel was associated with down-regulation of osteogenic signal and attenuation of matrix vesicle release. Our results indicate that microtubule plays a central role in vascular calcification, and that microtubule stabilization represents a potential new approach to the treatment of this condition. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Inhibition of Flowering of Xanthium pensylvanicum Wallr. by Prolonged Irradiation with Far Red

    PubMed Central

    Mancinelli, Alberto L.; Downs, Robert J.

    1967-01-01

    Interrupting each long night with a prolonged period of far red radiant energy resulted in the inhibition of floral initiation in cocklebur. Irradiations inducing different relative levels of PFR from 1 to 2% to 80% had about the same effect under 4-hour photoperiods. The lower levels of PFR induced by continuous far red irradiation were not as effective as the higher levels induced by red under 8 and 12-hours photoperiods. The critical PFR level required to induce inhibition of flowering seems to increase with increasing photoperiods. PMID:16656490

  1. Cyclosporin A Inhibits Smooth Muscle Proliferation in the Vascular Response to Injury

    NASA Astrophysics Data System (ADS)

    Jonasson, Lena; Holm, Jan; Hansson, Goran K.

    1988-04-01

    The arterial response to injury is dominated by proliferation of smooth muscle cells and infiltration of blood-borne cells in the vascular intima. Arterial smooth muscle cell proliferation is under growth factor control, but how this regulation operates in vivo is unclear. We studied the effect on arterial response to mechanical injury of cyclosporin A, a drug that inhibits T-lymphocyte activation. Cyclosporin A treatment at surgery caused a persistent inhibition of the intimal proliferative lesion. Cyclosporin A also inhibited expression of Ia antigens on smooth muscle cells in situ but had no direct effects on smooth muscle cell proliferation in culture. Therefore, the inhibition of intimal cell proliferation appears to be mediated via the immune system.

  2. Inhibition of the Ca sup 2+ -ATPase of vascular smooth muscle sarcoplasmic reticulum by superoxide radicals

    SciTech Connect

    Suzuki, Yuichiro; Ford, G.D. )

    1991-03-15

    The effect of oxygen free radicals generated by hypoxanthine plus xanthine oxidase on the Ca{sup 2+}-ATPase of sarcoplasmic reticulum from bovine aortic smooth muscle were studied. Exogenous hypoxanthine plus xanthine oxidase produced an hypoxanthine concentration dependent inhibition of the Ca{sup 2+}-ATPase. The inhibition could be completely blocked by superoxide dismutase but not by either mannitol or deferoxamine. Direct addition of reagent hydrogen peroxide in the {mu}M range did not cause significant inhibition. These results suggest that superoxide is the primary damaging species. Additionally, 1.16 {plus minus} 0.17 mU/g wet wt of xanthine oxidase activity were detected in the post-nuclear supernatant of bovine aortic smooth muscle, suggesting the existence of a possible intracellular source of superoxide. This value was calculated to be approximately 5 mU/ml by using a usual value of vascular smooth muscle cellular volume. Thus the level of endogenous xanthine oxidase resident in vascular smooth muscle is comparable with the level of exogenous xanthine oxidase used in the present study. These findings suggest a potential role of xanthine oxidase-generated superoxide in free radical injury to vascular smooth muscle.

  3. Glucagon-like peptide-1 inhibits vascular smooth muscle cell dedifferentiation through mitochondrial dynamics regulation.

    PubMed

    Torres, Gloria; Morales, Pablo E; García-Miguel, Marina; Norambuena-Soto, Ignacio; Cartes-Saavedra, Benjamín; Vidal-Peña, Gonzalo; Moncada-Ruff, David; Sanhueza-Olivares, Fernanda; San Martín, Alejandra; Chiong, Mario

    2016-03-15

    Glucagon-like peptide-1 (GLP-1) is a neuroendocrine hormone produced by gastrointestinal tract in response to food ingestion. GLP-1 plays a very important role in the glucose homeostasis by stimulating glucose-dependent insulin secretion, inhibiting glucagon secretion, inhibiting gastric emptying, reducing appetite and food intake. Because of these actions, the GLP-1 peptide-mimetic exenatide is one of the most promising new medicines for the treatment of type 2 diabetes. In vivo treatments with GLP-1 or exenatide prevent neo-intima layer formation in response to endothelial damage and atherosclerotic lesion formation in aortic tissue. Whether GLP-1 modulates vascular smooth muscle cell (VSMC) migration and proliferation by controlling mitochondrial dynamics is unknown. In this report, we showed that GLP-1 increased mitochondrial fusion and activity in a PKA-dependent manner in the VSMC cell line A7r5. GLP-1 induced a Ser-637 phosphorylation in the mitochondrial fission protein Drp1, and decreased Drp1 mitochondrial localization. GLP-1 inhibited PDGF-BB-induced VSMC migration and proliferation, actions inhibited by overexpressing wild type Drp1 and mimicked by the Drp1 inhibitor Mdivi-1 and by overexpressing dominant negative Drp1. These results show that GLP-1 stimulates mitochondrial fusion, increases mitochondrial activity and decreases PDGF-BB-induced VSMC dedifferentiation by a PKA/Drp1 signaling pathway. Our data suggest that GLP-1 inhibits vascular remodeling through a mitochondrial dynamics-dependent mechanism. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Inhibition of prolyl hydroxylase domain-containing protein downregulates vascular angiotensin II type 1 receptor.

    PubMed

    Matsuura, Hirohide; Ichiki, Toshihiro; Ikeda, Jiro; Takeda, Kotaro; Miyazaki, Ryohei; Hashimoto, Toru; Narabayashi, Eriko; Kitamoto, Shiro; Tokunou, Tomotake; Sunagawa, Kenji

    2011-09-01

    Inhibition of prolyl hydroxylase domain-containing protein (PHD) by hypoxia stabilizes hypoxia-inducible factor 1 and increases the expression of target genes, such as vascular endothelial growth factor. Although the systemic renin-angiotensin system is activated by hypoxia, the role of PHD in the regulation of the renin-angiotensin system remains unknown. We examined the effect of PHD inhibition on the expression of angiotensin II type 1 receptor (AT(1)R). Hypoxia, cobalt chloride, and dimethyloxalylglycine, all known to inhibit PHD, reduced AT(1)R expression in vascular smooth muscle cells. Knockdown of PHD2, a major isoform of PHDs, by RNA interference also reduced AT(1)R expression. Cobalt chloride diminished angiotensin II-induced extracellular signal-regulated kinase phosphorylation. Cobalt chloride decreased AT(1)R mRNA through transcriptional and posttranscriptional mechanisms. Oral administration of cobalt chloride (14 mg/kg per day) to C57BL/6J mice receiving angiotensin II infusion (490 ng/kg per minute) for 4 weeks significantly attenuated perivascular fibrosis of the coronary arteries without affecting blood pressure level. These data suggest that PHD inhibition may be beneficial for the treatment of cardiovascular diseases by inhibiting renin-angiotensin system via AT(1)R downregulation.

  5. Heparin fragments inhibit human vascular smooth muscle cell proliferation in vitro

    SciTech Connect

    Selden, S.C.; Johnson, W.V.; Maciag, T.

    1986-03-01

    The authors have examined the effect of heparin on human abdominal aortic smooth muscle cell growth. Cell proliferation was inhibited by more than 90% at a concentration of 20 ..mu..g/ml in a 12 day growth assay using heparin from Sigma, Upjohn or Calbiochem. Additionally, 200 ..mu..g/ml Upjohn heparin inhibits /sup 3/H-thymidine incorporation by 50% in short term assays using serum or purified platelet-derived growth factor (25-100ng/ml) to initiate the cell cycle. Homogeneous size classes of heparin fragments were prepared by nitrous acid cleavage and BioGel P-10 filtration chromatography. Deca-, octa-, hexa-, tetra-, and di-saccharides inhibited proliferation by 90% at concentrations of 280, 320, 260, 180 and 100 ..mu..g/ml, respectively, in a 12 day growth assay. These data confirm the work of Castellot et.al. and extend the range of inhibitory fragments down to the tetra- and di-saccharide size. These data suggest, therefore, that di-saccharide subunit of heparin is sufficient to inhibit vascular smooth muscle cell proliferation. The authors are now examining the role of the anhydromannose moiety on the reducing end of the nitrous acid generated fragments as a possible mediator of heparin-induced inhibition of vascular smooth muscle cell proliferation.

  6. Carboxylated nanodiamonds inhibit γ-irradiation damage of human red blood cells.

    PubMed

    Santacruz-Gomez, K; Silva-Campa, E; Melendrez-Amavizca, R; Teran Arce, F; Mata-Haro, V; Landon, P B; Zhang, C; Pedroza-Montero, M; Lal, R

    2016-04-07

    Nanodiamonds when carboxylated (cNDs) act as reducing agents and hence could limit oxidative damage in biological systems. Gamma (γ)-irradiation of whole blood or its components is required in immunocompetent patients to prevent transfusion-associated graft versus host disease (TA-GVHD). However, γ-irradiation of blood also deoxygenates red blood cells (RBCs) and induces oxidative damage, including abnormalities in cellular membranes and hemolysis. Using atomic force microscopy (AFM) and Raman spectroscopy, we examined the effect of cNDs on γ-irradiation mediated deoxygenation and morphological damage of RBCs. γ-Radiation induced several morphological phenotypes, including stomatocytes, codocytes and echinocytes. While stomatocytes and codocytes are reversibly damaged RBCs, echinocytes are irreversibly damaged. AFM images show significantly fewer echinocytes among cND-treated γ-irradiated RBCs. The Raman spectra of γ-irradiated RBCs had more oxygenated hemoglobin patterns when cND-treated, resembling those of normal, non-irradiated RBCs, compared to the non-cND-treated RBCs. cND inhibited hemoglobin deoxygenation and morphological damage, possibly by neutralizing the free radicals generated during γ-irradiation. Thus cNDs have the therapeutic potential to preserve the quality of stored blood following γ-irradiation.

  7. Phosphodiesterase 5 inhibition ameliorates angiotensin II-dependent hypertension and renal vascular dysfunction.

    PubMed

    Thieme, Manuel; Sivritas, Sema H; Mergia, Evanthia; Potthoff, Sebastian A; Yang, Guang; Hering, Lydia; Grave, Katharina; Hoch, Henning; Rump, Lars C; Stegbauer, Johannes

    2017-03-01

    Changes in renal hemodynamics have a major impact on blood pressure (BP). Angiotensin (Ang) II has been shown to induce vascular dysfunction by interacting with phosphodiesterase (PDE)1 and PDE5. The predominant PDE isoform responsible for renal vascular dysfunction in hypertension is unknown. Here, we measured the effects of PDE5 (sildenafil) or PDE1 (vinpocetine) inhibition on renal blood flow (RBF), BP, and renal vascular function in normotensive and hypertensive mice. During acute short-term Ang II infusion, sildenafil decreased BP and increased RBF in C57BL/6 (WT) mice. In contrast, vinpocetine showed no effect on RBF and BP. Additionally, renal cGMP levels were significantly increased after acute sildenafil but not after vinpocetine infusion, indicating a predominant role of PDE5 in renal vasculature. Furthermore, chronic Ang II infusion (500 ng·kg(-1)·min(-1)) increased BP and led to impaired NO-dependent vasodilation in kidneys of WT mice. Additional treatment with sildenafil (100 mg·kg(-1)·day(-1)) attenuated Ang II-dependent hypertension and improved NO-mediated vasodilation. During chronic Ang II infusion, urinary nitrite excretion, a marker for renal NO generation, was increased in WT mice, whereas renal cGMP generation was decreased and restored after sildenafil treatment, suggesting a preserved cGMP signaling after PDE5 inhibition. To investigate the dependency of PDE5 effects on NO/cGMP signaling, we next analyzed eNOS-KO mice, a mouse model characterized by low vascular NO/cGMP levels. In eNOS-KO mice, chronic Ang II infusion increased BP but did not impair NO-mediated vasodilation. Moreover, sildenafil did not influence BP or vascular function in eNOS-KO mice. These results highlight PDE5 as a key regulator of renal hemodynamics in hypertension. Copyright © 2017 the American Physiological Society.

  8. Sulforaphane inhibits restenosis by suppressing inflammation and the proliferation of vascular smooth muscle cells.

    PubMed

    Kwon, Jin-Sook; Joung, Hosouk; Kim, Yong Sook; Shim, Young-Sun; Ahn, Youngkeun; Jeong, Myung Ho; Kee, Hae Jin

    2012-11-01

    Sulforaphane, a naturally occurring organosulfur compound in broccoli, has chemopreventive properties in cancer. However, the effects of sulforaphane in vascular diseases have not been examined. We therefore aimed to investigate the effects of sulforaphane on vascular smooth muscle cell (VSMC) proliferation and neointimal formation and the related mechanisms. The expression of vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) was examined in VSMCs. The nuclear translocation of nuclear factor-κB (NF-κB) and GATA6 expression was examined in VSMCs and in a carotid artery injury model by Western blot and immunohistochemistry. We also investigated whether local delivery of sulforaphane affected neointimal formation. Sulforaphane inhibited the mRNA and protein expression of VCAM-1 induced by tumor necrosis factor (TNF)-α in VSMCs. Treatment of VSMCs with sulforaphane blocked TNF-α-induced IκBα degradation and NF-κB p65 and GATA6 expression. Furthermore, NF-κB p65 and GATA6 expression were reduced in sulforaphane-treated carotid injury sections. Notably, binding of GATA6 to the VCAM-1 promoter was dramatically reduced by sulforaphane. The MTT, BrdU incorporation, and in vitro scratch assays revealed that the proliferation and migration of VSMCs were reduced by sulforaphane. Furthermore, local administration of sulforaphane significantly reduced neointima formation 14 days after vascular injury in rats. Our results indicate that sulforaphane inhibits neointima formation via targeting of adhesion molecules through the suppression of NF-κB/GATA6. Furthermore, sulforaphane regulates migration and proliferation in VSMCs. Sulforaphane may be a potential therapeutic agent for preventing restenosis after vascular injury. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  9. Naringenin Inhibits UVB Irradiation-Induced Inflammation and Oxidative Stress in the Skin of Hairless Mice.

    PubMed

    Martinez, Renata M; Pinho-Ribeiro, Felipe A; Steffen, Vinicius S; Caviglione, Carla V; Vignoli, Josiane A; Barbosa, Décio S; Baracat, Marcela M; Georgetti, Sandra R; Verri, Waldiceu A; Casagrande, Rubia

    2015-07-24

    Ultraviolet B (UVB) irradiation may cause inflammation- and oxidative-stress-dependent skin cancer and premature aging. Naringenin (1) has been reported to have anti-inflammatory and antioxidant properties, but its effects and mechanisms on UVB irradiation-induced inflammation and oxidative stress are still not known. Thus, the present study aimed to investigate the potential of naringenin to mitigate UVB irradiation-induced inflammation and oxidative damage in the skin of hairless mice. Skin edema, myeloperoxidase (neutrophil marker) and matrix metalloproteinase-9 (MMP-9) activity, and cytokine production were measured after UVB irradiation. Oxidative stress was evaluated by 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS) scavenging ability, ferric reducing antioxidant power (FRAP), reduced glutathione levels, catalase activity, lipid peroxidation products, superoxide anion production, and gp91phox (NADPH oxidase subunit) mRNA expression by quantitative PCR. The intraperitoneal treatment with naringenin reduced skin inflammation by inhibiting skin edema, neutrophil recruitment, MMP-9 activity, and pro-inflammatory (TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-6, IL-12, IL-13, IL-17, IL-22, and IL-23) and anti-inflammatory (TGF-β and IL-10) cytokines. Naringenin also inhibited oxidative stress by reducing superoxide anion production and the mRNA expression of gp91phox. Therefore, naringenin inhibits UVB irradiation-induced skin damage and may be a promising therapeutic approach to control skin disease.

  10. 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

  11. 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

  12. 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.

  13. Peptidylarginine Deiminase Inhibition Reduces Vascular Damage and Modulates Innate Immune Responses in Murine Models of Atherosclerosis

    PubMed Central

    Knight, Jason S.; Luo, Wei; O’Dell, Alexander A.; Yalavarthi, Srilakshmi; Zhao, Wenpu; Subramanian, Venkataraman; Guo, Chiao; Grenn, Robert C.; Thompson, Paul R.; Eitzman, Daniel T.; Kaplan, Mariana J.

    2014-01-01

    Rationale Neutrophil extracellular trap (NET) formation promotes vascular damage, thrombosis, and activation of interferon-α-producing plasmacytoid dendritic cells in diseased arteries. Peptidylarginine deiminase inhibition is a strategy that can decrease in vivo NET formation. Objective To test whether peptidylarginine deiminase inhibition, a novel approach to targeting arterial disease, can reduce vascular damage and inhibit innate immune responses in murine models of atherosclerosis. Methods and Results Apolipoprotein-E (Apoe)−/− mice demonstrated enhanced NET formation, developed autoantibodies to NETs, and expressed high levels of interferon-α in diseased arteries. Apoe−/− mice were treated for 11 weeks with daily injections of Cl-amidine, a peptidylarginine deiminase inhibitor. Peptidylarginine deiminase inhibition blocked NET formation, reduced atherosclerotic lesion area, and delayed time to carotid artery thrombosis in a photochemical injury model. Decreases in atherosclerosis burden were accompanied by reduced recruitment of netting neutrophils and macrophages to arteries, as well as by reduced arterial interferon-α expression. Conclusions Pharmacological interventions that block NET formation can reduce atherosclerosis burden and arterial thrombosis in murine systems. These results support a role for aberrant NET formation in the pathogenesis of atherosclerosis through modulation of innate immune responses. PMID:24425713

  14. recA gene product is responsible for inhibition of deoxyribonucleic acid synthesis after ultraviolet irradiation.

    PubMed Central

    Trgovcević, Z; Petranović, D; Petranović, M; Salaj-Smic, E

    1980-01-01

    Deoxyribonucleic acid synthesis after ultraviolet irradiation was studied in wild-type, uvrA, recB, recA recB, and recA Escherichia coli strains. Inhibition of deoxyribonucleic acid synthesis, which occurs almost immediately after exposing the cells to ultraviolet radiation, depends on the functional gene recA. PMID:6997276

  15. Hydrogen sulfide inhibits the calcification and osteoblastic differentiation of vascular smooth muscle cells

    PubMed Central

    Zavaczki, Erzsébet; Jeney, Viktória; Agarwal, Anupam; Zarjou, Abolfazl; Oros, Melinda; Katkó, Mónika; Varga, Zsuzsa; Balla, György; Balla, József

    2011-01-01

    Osteoblastic differentiation of vascular smooth muscle cells (VSMCs) is involved in the pathogenesis of vascular calcification. Hydrogen sulfide (H2S) is a gas endogenously produced by cystathionine γ-lyase in VSMC. Here we determined whether H2S plays a role in phosphate-induced osteoblastic transformation and mineralization of VSMC. Hydrogen sulfide was found to inhibit calcium deposition in the extracellular matrix and to suppress the induction of the genes involved in osteoblastic transformation of VSMC: alkaline phosphatase, osteocalcin, and Cbfa1. Moreover, phosphate uptake and phosphate-triggered upregulation of the sodium-dependent phosphate cotransporter (Pit-1) were also prevented by H2S. Reduction of endogenous production of H2S by inhibition of cystathionine γ-lyase activity resulted in increased osteoblastic transformation and mineralization. Low plasma levels of H2S, associated with decreased cystathionine γ-lyase enzyme activity, were found in patients with chronic kidney disease receiving hemodialysis. Thus, H2S is a potent inhibitor of phosphate-induced calcification and osteoblastic differentiation of VSMC. This mechanism might contribute to accelerated vascular calcification in chronic kidney disease. PMID:21716261

  16. The Hemoglobin Homolog Cytoglobin in Smooth Muscle Inhibits Apoptosis and Regulates Vascular Remodeling.

    PubMed

    Jourd'heuil, Frances L; Xu, Haiyan; Reilly, Timothy; McKellar, Keneta; El Alaoui, Chaymae; Steppich, Julia; Liu, Yong Feng; Zhao, Wen; Ginnan, Roman; Conti, David; Lopez-Soler, Reynold; Asif, Arif; Keller, Rebecca K; Schwarz, John J; Thanh Thuy, Le Thi; Kawada, Norifumi; Long, Xiaochun; Singer, Harold A; Jourd'heuil, David

    2017-10-01

    The role of hemoglobin and myoglobin in the cardiovascular system is well established, yet other globins in this context are poorly characterized. Here, we examined the expression and function of cytoglobin (CYGB) during vascular injury. We characterized CYGB content in intact vessels and primary vascular smooth muscle (VSM) cells and used 2 different vascular injury models to examine the functional significance of CYGB in vivo. We found that CYGB was strongly expressed in medial arterial VSM and human veins. In vitro and in vivo studies indicated that CYGB was lost after VSM cell dedifferentiation. In the rat balloon angioplasty model, site-targeted delivery of adenovirus encoding shRNA specific for CYGB prevented its reexpression and decreased neointima formation. Similarly, 4 weeks after complete ligation of the left common carotid, Cygb knockout mice displayed little to no evidence of neointimal hyperplasia in contrast to their wild-type littermates. Mechanistic studies in the rat indicated that this was primarily associated with increased medial cell loss, terminal uridine nick-end labeling staining, and caspase-3 activation, all indicative of prolonged apoptosis. In vitro, CYGB could be reexpressed after VSM stimulation with cytokines and hypoxia and loss of CYGB sensitized human and rat aortic VSM cells to apoptosis. This was reversed after antioxidant treatment or NOS2 (nitric oxide synthase 2) inhibition. These results indicate that CYGB is expressed in vessels primarily in differentiated medial VSM cells where it regulates neointima formation and inhibits apoptosis after injury. © 2017 American Heart Association, Inc.

  17. SIRT1 inhibits angiotensin II-induced vascular smooth muscle cell hypertrophy.

    PubMed

    Li, Li; Gao, Peng; Zhang, Huina; Chen, Houzao; Zheng, Wei; Lv, Xiang; Xu, Tingting; Wei, Yusheng; Liu, Depei; Liang, Chihchuan

    2011-02-01

    Angiotensin II (Ang II) stimulates vascular smooth muscle cell (VSMC) hypertrophy as a critical event in the development of vascular diseases such as atherosclerosis. Sirtuin (SIRT) 1, a nicotinamide adenine dinucleotide dependent deacetylase, has been demonstrated to exert protective effects in atherosclerosis by promoting endothelium-dependent vascular relaxation and reducing macrophage foam cell formation, but its role in VSMC hypertrophy remains unknown. In this study, we tried to investigate the effect of SIRT1 on Ang II-induced VSMC hypertrophy. Results showed that adenoviral-mediated over-expression of SIRT1 significantly inhibited Ang II-induced VSMC hypertrophy, while knockdown of SIRT1 by RNAi resulted in an increased [(3)H]-leucine incorporation of VSMC. Accordingly, nicotinamide adenine dinucleotide phosphate oxidase 1 (Nox1) expression induced by Ang II was inhibited by SIRT1 in VSMCs. SIRT1 activator resveratrol decreased, whereas endogenous SIRT1 inhibitor nicotinamide increased Nox1 expression in A7r5 VSMCs. Furthermore, transcription factor GATA-6 was involved in the down-regulation of Nox1 expression by SIRT1. These results provide new insight into SIRT1's anti-atherogenic properties by suppressing Ang II-induced VSMC hypertrophy.

  18. Protocatechuic aldehyde inhibits migration and proliferation of vascular smooth muscle cells and intravascular thrombosis

    SciTech Connect

    Moon, Chang Yoon; Ku, Cheol Ryong; Cho, Yoon Hee; Lee, Eun Jig

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer Protocatechuic aldehyde (PCA) inhibits ROS production in VSMCs. Black-Right-Pointing-Pointer PCA inhibits proliferation and migration in PDGF-induced VSMCs. Black-Right-Pointing-Pointer PCA has anti-platelet effects in ex vivo rat whole blood. Black-Right-Pointing-Pointer We report the potential therapeutic role of PCA in atherosclerosis. -- Abstract: The migration and proliferation of vascular smooth muscle cells (VSMCs) and formation of intravascular thrombosis play crucial roles in the development of atherosclerotic lesions. This study examined the effects of protocatechuic aldehyde (PCA), a compound isolated from the aqueous extract of the root of Salvia miltiorrhiza, an herb used in traditional Chinese medicine to treat a variety of vascular diseases, on the migration and proliferation of VSMCs and platelets due to platelet-derived growth factor (PDGF). DNA 5-bromo-2 Prime -deoxy-uridine (BrdU) incorporation and wound-healing assays indicated that PCA significantly attenuated PDGF-induced proliferation and migration of VSMCs at a pharmacologically relevant concentration (100 {mu}M). On a molecular level, we observed down-regulation of the phosphatidylinositol 3-kinase (PI3K)/Akt and the mitogen-activated protein kinase (MAPK) pathways, both of which regulate key enzymes associated with migration and proliferation. We also found that PCA induced S-phase arrest of the VSMC cell cycle and suppressed cyclin D2 expression. In addition, PCA inhibited PDGF-BB-stimulated reactive oxygen species production in VSMCs, indicating that PCA's antioxidant properties may contribute to its suppression of PDGF-induced migration and proliferation in VSMCs. Finally, PCA exhibited an anti-thrombotic effect related to its inhibition of platelet aggregation, confirmed with an aggregometer. Together, these findings suggest a potential therapeutic role of PCA in the treatment of atherosclerosis and angioplasty-induced vascular restenosis.

  19. Diminution of signal transducer and activator of transcription 3 signaling inhibits vascular permeability and anaphylaxis.

    PubMed

    Hox, Valerie; O'Connell, Michael P; Lyons, Jonathan J; Sackstein, Paul; Dimaggio, Thomas; Jones, Nina; Nelson, Celeste; Boehm, Manfred; Holland, Steven M; Freeman, Alexandra F; Tweardy, David J; Olivera, Ana; Metcalfe, Dean D; Milner, Joshua D

    2016-07-01

    During IgE-mediated immediate hypersensitivity reactions, vascular endothelial cells permeabilize in response to mast cell mediators. We have demonstrated previously that patients and mice with signal transducer and activator of transcription 3 (STAT3) mutations (autosomal dominant hyper-IgE syndrome [AD-HIES]) are partially protected from anaphylaxis. We sought to study the mechanism by which STAT3 contributes to anaphylaxis and determine whether small-molecule inhibition of STAT3 can prevent anaphylaxis. Using unaffected and STAT3-inhibited or genetic loss-of-function samples, we performed histamine skin prick tests, investigated the contribution of STAT3 to animal models of anaphylaxis, and measured endothelial cell permeability, gene and protein expression, and histamine receptor-mediated signaling. Although mouse mast cell degranulation was minimally affected by STAT3 blockade, mast cell mediator-induced anaphylaxis was blunted in Stat3 mutant mice with AD-HIES and in wild-type mice subjected to small-molecule STAT3 inhibition. Histamine skin prick test responses were diminished in patients with AD-HIES. Human umbilical vein endothelial cells derived from patients with AD-HIES or treated with a STAT3 inhibitor did not signal properly through Src or cause appropriate dissolution of the adherens junctions made up of the proteins vascular endothelial-cadherin and β-catenin. Furthermore, we found that diminished STAT3 target microRNA17-92 expression in human umbilical vein endothelial cells from patients with AD-HIES is associated with increased phosphatase and tensin homolog (PTEN) expression, which inhibits Src, and increased E2F transcription factor 1 expression, which regulates β-catenin cellular dynamics. These data demonstrate that STAT3-dependent transcriptional activity regulates critical components for the architecture and functional dynamics of endothelial junctions, thus permitting vascular permeability. Published by Elsevier Inc.

  20. The effects of different schedules of total-body irradiation in heterotopic vascularized bone transplantation. An experimental study in the Lewis rat

    SciTech Connect

    Gonzalez del Pino, J.; Benito, M.; Randolph, M.A.; Weiland, A.J. )

    1990-12-01

    To evaluate the effects of irradiation on heterotopically placed vascularized knee isografts, a single dose of 10 Gy of total-body irradiation was given to Lewis donor rats. Irradiation was delivered either 2 or 6 days prior to harvesting or subsequent transplantation, and evaluated at 1, 2, and 4 weeks after grafting. Irradiation caused endothelial depopulation of the graft artery, although vascular pedicle patency was maintained throughout the study. Bone graft viability and mineralization were normal. Dramatic changes in the bone marrow were seen that included an increase of its fat content (P less than 0.001), and a concomitant decrease in bone marrow-derived immunocompetent cells. These changes were more prominent in recipients of grafts from day -6 irradiated donor rats. Total-body irradiation did not prejudice the use of vascularized bone grafts, and exhibited an associated immunosuppresant effect over the vascular endothelium and bone marrow. This may be a further rational conditioning procedure to avoid recipient manipulation in vascularized bone allotransplantation.

  1. Knockdown of connexin 43 attenuates balloon injury-induced vascular restenosis through the inhibition of the proliferation and migration of vascular smooth muscle cells.

    PubMed

    Han, Xiao-Jian; He, Dan; Xu, Liang-Jing; Chen, Min; Wang, Yi-Qi; Feng, Jiu-Geng; Wei, Min-Jun; Hong, Tao; Jiang, Li-Ping

    2015-11-01

    Coronary artery disease (CAD) or atherosclerotic heart disease is one of the most common types of cardiovascular disease. Although percutaneous coronary intervention [PCI or percutaneous transluminal coronary angioplasty (PTCA)] is a mature, well-established technique used to treat atherosclerotic heart disease, its long‑term therapeutic effects are compromised by a high incidence of vascular restenosis (RS) following angioplasty. In our previous study, we found that the principal gap junction protein, connexin 43 (Cx43), in vascular smooth muscle cells (VSMCs) was involved in the development of vascular RS following angioplasty-induced balloon injury. However, the exact role action of Cx43 in vascular RS remains unclear. In the present study, we aimed to further examine whether the knockdown of Cx43 attenuates the development of vascular RS through the inhibition of the proliferation and migration of VSMCs. We found that the use of a lentiviral vector expressing shRNA targeting Cx43 (Cx43‑RNAi-LV) efficiently silenced the mRNA and protein expression of Cx43 in cultured VSMCs. In addition, MTT and Transwell assays were used to examined the proliferation and migration of the VSMCs, respectively. The results revealed that the knockdown of Cx43 by Cx43-RNAi-LV at a multiplicity of infection (MOI) of 100 significantly inhibited the proliferation and migration of the VSMCs in vitro. Notably, the knockdown of Cx43 also effectively attenuated the development of vascular RS and intimal hyperplasia following balloon injury in vivo. Taken together, our data suggest that Cx43 is involved in the development of vascular RS and intimal hyperplasia through the regulation of the proliferation and migration of VSMCs. Thus, the present study provides new insight into the pathogenesis of vascular RS, and suggests that further comfirms that Cx43 may well be a novel potential pharmacological target for preventing vascular RS following PCI.

  2. Novel Pyridazinone Inhibitors for Vascular Adhesion Protein-1 (VAP-1): Old target – New Inhibition Mode

    PubMed Central

    Bligt-Lindén, Eva; Pihlavisto, Marjo; Szatmári, István; Otwinowski, Zbyszek; Smith, David J.; Lázár, László; Fülöp, Ferenc; Salminen, Tiina A.

    2014-01-01

    Vascular adhesion protein-1 (VAP-1) is a primary amine oxidase and a drug target for inflammatory and vascular diseases. Despite extensive attempts to develop potent, specific and reversible inhibitors of its enzyme activity, the task has proven challenging. Here we report the synthesis, inhibitory activity and molecular binding mode of novel pyridazinone inhibitors, which show specificity for VAP-1 over monoamine and diamine oxidases. The crystal structures of three inhibitor-VAP-1 complexes show that these compounds bind reversibly into a unique binding site in the active site channel. Though they are good inhibitors of human VAP-1, they do not inhibit rodent VAP-1 well. To investigate this further, we used homology modeling and structural comparison to identify amino acid differences, which explain the species-specific binding properties. Our results prove the potency and specificity of these new inhibitors and the detailed characterization of their binding mode is of importance for further development of VAP-1 inhibitors. PMID:24304424

  3. Novel pyridazinone inhibitors for vascular adhesion protein-1 (VAP-1): old target-new inhibition mode.

    PubMed

    Bligt-Lindén, Eva; Pihlavisto, Marjo; Szatmári, István; Otwinowski, Zbyszek; Smith, David J; Lázár, László; Fülöp, Ferenc; Salminen, Tiina A

    2013-12-27

    Vascular adhesion protein-1 (VAP-1) is a primary amine oxidase and a drug target for inflammatory and vascular diseases. Despite extensive attempts to develop potent, specific, and reversible inhibitors of its enzyme activity, the task has proven challenging. Here we report the synthesis, inhibitory activity, and molecular binding mode of novel pyridazinone inhibitors, which show specificity for VAP-1 over monoamine and diamine oxidases. The crystal structures of three inhibitor-VAP-1 complexes show that these compounds bind reversibly into a unique binding site in the active site channel. Although they are good inhibitors of human VAP-1, they do not inhibit rodent VAP-1 well. To investigate this further, we used homology modeling and structural comparison to identify amino acid differences, which explain the species-specific binding properties. Our results prove the potency and specificity of these new inhibitors, and the detailed characterization of their binding mode is of importance for further development of VAP-1 inhibitors.

  4. Understanding the continuum of radionecrosis and vascular disorders in the brain following gamma knife irradiation: An MRI study.

    PubMed

    Constanzo, Julie; Masson-Côté, Laurence; Tremblay, Luc; Fouquet, Jérémie P; Sarret, Philippe; Geha, Sameh; Whittingstall, Kevin; Paquette, Benoit; Lepage, Martin

    2017-10-01

    The radiation dose delivered to brain tumors is limited by the possibility to induce vascular damage and necrosis in surrounding healthy tissue. In the present study, we assessed the ability of MRI to monitor the cascade of events occurring in the healthy rat brain after stereotactic radiosurgery, which could be used to optimize the radiation treatment planning. The primary somatosensory forelimb area (S1FL) and the primary motor cortex in the right hemisphere of Fischer rats (n = 6) were irradiated with a single dose of Gamma Knife radiation (Leksell Perfexion, Elekta AG, Stockholm, Sweden). Rats were scanned with a small-animal 7 Tesla MRI scanner before treatment and 16, 21, 54, 82, and 110 days following irradiation. At every imaging session, T2 -weighted (T2 w), Gd-DTPA dynamic contrast-enhanced MRI (DCE-MRI), and T2*-weighted ( T2* w) images were acquired to measure changes in fluid content, blood vessel permeability, and structure, respectively. At days 10, 110, and 140, histopathology was performed on brain sections. Locomotion and spatial memory ability were assessed longitudinally by behavioral tests. No vascular changes were initially observed. After 54 days, a small necrotic volume in the white matter below the S1FL, surrounded by an area presenting significant vascular permeability, was revealed. Between 54 and 110 days, the necrotic volume increased and was accompanied by the formation of a ring-like region, where a mixture of necrosis and permeable blood vessels were observed, as confirmed by histology. Behavioral changes were only observed after day 82. Together, DCE-MRI and T2* w images supported by histology provided a coherent picture of the phenomena involved in the formation of new, leaky blood vessels, which was followed by the detection of radionecrosis in a preclinical model of brain irradiation. Magn Reson Med 78:1420-1431, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic

  5. Lipoxin A4 inhibits immune cell binding to salivary epithelium and vascular endothelium.

    PubMed

    Chinthamani, Sreedevi; Odusanwo, Olutayo; Mondal, Nandini; Nelson, Joel; Neelamegham, Sriram; Baker, Olga J

    2012-04-01

    Lipoxins are formed by leukocytes during cell-cell interactions with epithelial or endothelial cells. Native lipoxin A(4) (LXA(4)) binds to the G protein-coupled lipoxin receptors formyl peptide receptor 2 (FPR2)/ALX and CysLT1. Furthermore, LXA(4) inhibits recruitment of neutrophils, by attenuating chemotaxis, adhesion, and transmigration across vascular endothelial cells. LXA(4) thus appears to serve as an endogenous "stop signal" for immune cell-mediated tissue injury (Serhan CN; Annu Rev Immunol 25: 101-137, 2007). The role of LXA(4) has not been addressed in salivary epithelium, and little is known about its effects on vascular endothelium. Here, we determined that interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) receptor activation in vascular endothelium and salivary epithelium upregulated the expression of adhesion molecules that facilitates the binding of immune cells. We hypothesize that the activation of the ALX/FPR2 and/or CysLT1 receptors by LXA(4) decreases this cytokine-mediated upregulation of cell adhesion molecules that enhance lymphocyte binding to both the vascular endothelium and salivary epithelium. In agreement with this hypothesis, we observed that nanomolar concentrations of LXA(4) blocked IL-1β- and TNF-α-mediated upregulation of E-selectin and intercellular cell adhesion molecule-1 (ICAM-1) on human umbilical vein endothelial cells (HUVECs). Binding of Jurkat cells to stimulated HUVECs was abrogated by LXA(4). Furthermore, LXA(4) preincubation with human submandibular gland cell line (HSG) also blocked TNF-α-mediated upregulation of vascular cell adhesion molecule-1 (VCAM-1) in these cells, and it reduced lymphocyte adhesion. These findings suggest that ALX/FPR2 and/or CysLT1 receptor activation in endothelial and epithelial cells blocks cytokine-induced adhesion molecule expression and consequent binding of lymphocytes, a critical event in the pathogenesis of Sjögren's syndrome (SS).

  6. Calphostin-C induction of vascular smooth muscle cell apoptosis proceeds through phospholipase D and microtubule inhibition.

    PubMed

    Zheng, Xi-Long; Gui, Yu; Du, Guangwei; Frohman, Michael A; Peng, Dao-Quan

    2004-02-20

    Calphostin-C, a protein kinase C inhibitor, induces apoptosis of cultured vascular smooth muscle cells. However, the mechanisms are not completely defined. Because apoptosis of vascular smooth muscle cells is critical in several proliferating vascular diseases such as atherosclerosis and restenosis after angioplasty, we decided to investigate the mechanisms underlying the calphostin-C-induced apoptotic pathway. We show here that apoptosis is inhibited by the addition of exogenous phosphatidic acid, a metabolite of phospholipase D (PLD), and that calphostin-C inhibits completely the activities of both isoforms of PLD, PLD1 and PLD2. Overexpression of either PLD1 or PLD2 prevented the vascular smooth muscle cell apoptosis induced by serum withdrawal but not the calphostin-C-elicited apoptosis. These data suggest that PLDs have anti-apoptotic effects and that complete inhibition of PLD activity by calphostin-C induces smooth muscle cell apoptosis. We also report that calphostin-C induced microtubule disruption and that the addition of exogenous phosphatidic acid inhibits calphostin-C effects on microtubules, suggesting a role for PLD in stabilizing the microtubule network. Overexpressing PLD2 in Chinese hamster ovary cells phenocopies this result, providing strong support for the hypothesis. Finally, taxol, a microtubule stabilizer, not only inhibited the calphostin-C-induced microtubule disruption but also inhibited apoptosis. We therefore conclude that calphostin-C induces apoptosis of cultured vascular smooth muscle cells through inhibiting PLD activity and subsequent microtubule polymerization.

  7. 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.

  8. Activation of peroxisome proliferator-activated receptor γ inhibits vascular calcification by upregulating Klotho

    PubMed Central

    Cheng, Lijuan; Zhang, Lei; Yang, Jun; Hao, Lirong

    2017-01-01

    Cardiovascular diseases are common in patients with chronic kidney disease. One of the key symptoms is the calcification of the vascular smooth muscle cells (VSMCs), which is induced by dysregulated mineral metabolism with high circulating levels of inorganic phosphate (Pi) and calcium. Klotho, which was originally identified as an aging suppressor gene, has been shown to be associated with vascular calcification. Since Klotho was recently identified as a target for nuclear receptor peroxisome proliferator-activated receptor (PPAR) γ, the present study aimed to determine whether PPARγ regulates VSMC calcification through modulating the expression levels of Klotho. It was demonstrated that the expression of PPARγ was downregulated during Pi-induced VSMC calcification. In addition, treatment with PPARγ agonists inhibited the calcification and enhanced the expression of Klotho in VSMCs in a PPARγ-dependent manner. Of note, loss of Klotho expression by RNA interference abolished the ability of PPARγ activation to inhibit VSMC calcification. Furthermore, activation of Klotho as well as PPARγ inhibited the expression of Pi transporter 1/2 and reduced Pi influx into VSMCs. To the best of our knowledge, the present study was the first to demonstrate that PPARγ regulates VSMC calcification through activating Klotho.

  9. 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.

  10. Nicotinamide Inhibits Vasculogenic Mimicry, an Alternative Vascularization Pathway Observed in Highly Aggressive Melanoma

    PubMed Central

    Shalmon, Bruria; Kubi, Adva; Treves, Avraham J.; Shapira-Frommer, Ronnie; Avivi, Camilla; Ortenberg, Rona; Ben-Ami, Eytan; Schachter, Jacob; Besser, Michal J.; Markel, Gal

    2013-01-01

    Vasculogenic mimicry (VM) describes functional vascular channels composed only of tumor cells and its presence predicts poor prognosis in melanoma patients. Inhibition of this alternative vascularization pathway might be of clinical importance, especially as several anti-angiogenic therapies targeting endothelial cells are largely ineffective in melanoma. We show the presence of VM structures histologically in a series of human melanoma lesions and demonstrate that cell cultures derived from these lesions form tubes in 3D cultures ex vivo. We tested the ability of nicotinamide, the amide form of vitamin B3 (niacin), which acts as an epigenetic gene regulator through unique cellular pathways, to modify VM. Nicotinamide effectively inhibited the formation of VM structures and destroyed already formed ones, in a dose-dependent manner. Remarkably, VM formation capacity remained suppressed even one month after the complete withdrawal of Nicotimamid. The inhibitory effect of nicotinamide on VM formation could be at least partially explained by a nicotinamide-driven downregulation of vascular endothelial cadherin (VE-Cadherin), which is known to have a central role in VM. Further major changes in the expression profile of hundreds of genes, most of them clustered in biologically-relevant clusters, were observed. In addition, nicotinamide significantly inhibited melanoma cell proliferation, but had an opposite effect on their invasion capacity. Cell cycle analysis indicated moderate changes in apoptotic indices. Therefore, nicotinamide could be further used to unravel new biological mechanisms that drive VM and tumor progression. Targeting VM, especially in combination with anti-angiogenic strategies, is expected to be synergistic and might yield substantial anti neoplastic effects in a variety of malignancies. PMID:23451174

  11. Inhibition of cerebral vascular inflammation by brain endothelium-targeted oligodeoxynucleotide complex.

    PubMed

    Hu, Jing; Al-Waili, Daniah; Hassan, Aishlin; Fan, Guo-Chang; Xin, Mei; Hao, Jiukuan

    2016-08-04

    The present study generated a novel DNA complex to specifically target endothelial NF-κB to inhibit cerebral vascular inflammation. This DNA complex (GS24-NFκB) contains a DNA decoy which inhibits NF-κB activity, and a DNA aptamer (GS-24), a ligand of transferrin receptor (TfR), which allows for targeted delivery of the DNA decoy into cells. The results indicate that GS24-NFκB was successfully delivered into a murine brain-derived endothelial cell line, bEND5, and inhibited inflammatory responses induced by tumor necrosis factor α (TNF-α) or oxygen-glucose deprivation/re-oxygenation (OGD/R) via down-regulation of the nuclear NF-κB subunit, p65, as well as its downstream inflammatory cytokines, inter-cellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM-1). The inhibitory effect of the GS24-NFκB was demonstrated by a significant reduction in TNF-α or OGD/R induced monocyte adhesion to the bEND5 cells after GS24-NFκB treatment. Intravenous (i.v.) injection of GS24-'NFκB (15mg/kg) was able to inhibit the levels of phoseph-p65 and VCAM-1 in brain endothelial cells in a mouse lipopolysaccharide (LPS)-induced inflammatory model in vivo. In conclusion, our approach using DNA nanotechnology for DNA decoy delivery could potentially be utilized for inhibition of inflammation in ischemic stroke and other neuro-inflammatory diseases affecting cerebral vasculature. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  12. Antidepressant-induced inhibition of genital vascular responses is reversed by vardenafil in female rabbits.

    PubMed

    Angulo, Javier; Cuevas, Pedro; Cuevas, Begona; Bischoff, Erwin; de Tejada, Iñigo Saenz

    2006-11-01

    Administration of serotonin reuptake inhibitors (SRI) or serotonin and norepinephrine reuptake inhibitors (SNRI) relieves depressive symptoms but may cause sexual dysfunction in women and men. The aim of the present study was to evaluate the effects of the phosphodiesterase type 5 (PDE5) inhibitor, vardenafil, on inhibition of genital vascular responses (GVR) induced by SRI or SNRI administration in female rabbits. Vaginal and clitoral vasodilatory responses to pelvic nerve electrical stimulation were measured by laser Doppler flow needle probes. GVR were significantly potentiated by vardenafil even at the low dose of 0.1 mg/kg, in clitoris and vagina (181 +/- 22% and 180 +/- 31% of control, in vagina and clitoris, respectively, at 8 Hz). The selective SRI, paroxetine (5 mg/kg), significantly inhibited GVR in female rabbits (54 +/- 5% and 48 +/- 6% of control). GVR were also significantly inhibited by the SNRIs, venlafaxine (5 mg/kg) (57 +/- 3% and 32 +/- 11%) and duloxetine (1 mg/kg) (40 +/- 7% and 28 +/- 5%). Treatment with vardenafil (0.1 and 0.3 mg/kg) completely reversed the inhibition of GVR induced by paroxetine, venlafaxine, or duloxetine. Potentiation of the nitric oxide (NO) pathway by vardenafil improves vascular sexual responses in female rabbits and overcomes the inhibitory effects of acutely administered antidepressants on GVR, irrespective of the underlying pathophysiologic mechanism, i.e., disruption of the NO pathway or enhancement of alpha-adrenergic mechanisms. PDE5 inhibition may represent a reasonable approach to treat SRI- or SRNI-induced female sexual dysfunction, in particular, arousal disorders.

  13. Roscovitine inhibits ERK1/2 activation induced by angiotensin II in vascular smooth muscle cells.

    PubMed

    Li, Ai-Ying; Han, Mei; Zheng, Bin; Wen, Jin-Kun

    2008-01-23

    Roscovitine is a potent CDK inhibitor often used as a biological tool in cell-cycle studies, but its working mechanism and real targets in vascular smooth muscle cells (VSMCs) remain unclear. In this study, we observed that ERK1/2 phosphorylation induced by Ang II was abrogated by pretreating VSMCs with roscovitine for 15h. Pretreating VSMCs with roscovitine also inhibited Ang II-induced c-Jun expression and phosphorylation. We further demonstrated that roscovitine could suppress the DNA binding activity of c-Jun and activation of angiotensinogen promoter by Ang II. These results suggest that roscovitine represses Ang II-induced angiotensinogen expression by inhibiting activation of ERK1/2 and c-Jun.

  14. Kaurane and pimarane-type diterpenes from the Viguiera species inhibit vascular smooth muscle contractility.

    PubMed

    Ambrosio, Sergio R; Tirapelli, Carlos R; da Costa, Fernando B; de Oliveira, Ana M

    2006-08-01

    The research, development and use of natural products as therapeutic agents, especially those derived from plants, have been increasing in recent years. Despite the fact that plants provide a rich source of novel biologically active compounds, only a small percentage have been phytochemically investigated and studied for their medical potential. Viguiera is a genus that belongs to the family Asteraceae and to the sunflower tribe Heliantheae, which is widespread mostly in Mexico and in other areas of the Andes and upland areas of Brazil. A review on the secondary metabolites pointed out that sesquiterpene lactones and diterpenes, of the kaurane and pimarane-type, are the main compounds produced by these plants. Some reports have shown that kaurane- and pimarane-type diterpenes exert several biological activities such as anti-inflammatory action, antimicrobial and antispasmodic activities. Kaurenoic and pimaradienoic acids, which are the main secondary metabolites isolated by our research group from the roots of Viguiera robusta and V. arenaria, respectively, have been evaluated on vascular smooth muscle contractility. We showed that these diterpenoids are able to inhibit the vascular contractility mainly by blocking extracellular Ca(2+) influx. Additionally, in this review we discuss the structure-activity relationship of the diterpenes regarding their inhibitory activity on vascular contractility.

  15. Pharmacological inhibition of PHOSPHO1 suppresses vascular smooth muscle cell calcification.

    PubMed

    Kiffer-Moreira, Tina; Yadav, Manisha C; Zhu, Dongxing; Narisawa, Sonoko; Sheen, Campbell; Stec, Boguslaw; Cosford, Nicholas D; Dahl, Russell; Farquharson, Colin; Hoylaerts, Marc F; Macrae, Vicky E; Millán, José Luis

    2013-01-01

    Medial vascular calcification (MVC) is common in patients with chronic kidney disease, obesity, and aging. MVC is an actively regulated process that resembles skeletal mineralization, resulting from chondro-osteogenic transformation of vascular smooth muscle cells (VSMCs). Here, we used mineralizing murine VSMCs to study the expression of PHOSPHO1, a phosphatase that participates in the first step of matrix vesicles-mediated initiation of mineralization during endochondral ossification. Wild-type (WT) VSMCs cultured under calcifying conditions exhibited increased Phospho1 gene expression and Phospho1(-/-) VSMCs failed to mineralize in vitro. Using natural PHOSPHO1 substrates, potent and specific inhibitors of PHOSPHO1 were identified via high-throughput screening and mechanistic analysis and two of these inhibitors, designated MLS-0390838 and MLS-0263839, were selected for further analysis. Their effectiveness in preventing VSMC calcification by targeting PHOSPHO1 function was assessed, alone and in combination with a potent tissue-nonspecific alkaline phosphatase (TNAP) inhibitor MLS-0038949. PHOSPHO1 inhibition by MLS-0263839 in mineralizing WT cells (cultured with added inorganic phosphate) reduced calcification in culture to 41.8% ± 2.0% of control. Combined inhibition of PHOSPHO1 by MLS-0263839 and TNAP by MLS-0038949 significantly reduced calcification to 20.9% ± 0.74% of control. Furthermore, the dual inhibition strategy affected the expression of several mineralization-related enzymes while increasing expression of the smooth muscle cell marker Acta2. We conclude that PHOSPHO1 plays a critical role in VSMC mineralization and that "phosphatase inhibition" may be a useful therapeutic strategy to reduce MVC.

  16. Niacin inhibits vascular inflammation via downregulating nuclear transcription factor-κB signaling pathway.

    PubMed

    Si, Yanhong; Zhang, Ying; Zhao, Jilong; Guo, Shoudong; Zhai, Lei; Yao, Shutong; Sang, Hui; Yang, Nana; Song, Guohua; Gu, Jue; Qin, Shucun

    2014-01-01

    The study aimed to investigate the effect of niacin on vascular inflammatory lesions in vivo and in vitro as well as its lipid-regulating mechanism. In vivo study revealed that niacin downregulated the levels of inflammatory factors (IL-6 and TNF-α) in plasma, suppressed protein expression of CD68 and NF-κB p65 in arterial wall, and attenuated oxidative stress in guinea pigs that have been fed high fat diet. In vitro study further confirmed that niacin decreased the secretion of IL-6 and TNF-α and inhibited NF-κB p65 and notch1 protein expression in oxLDL-stimulated HUVECs and THP-1 macrophages. Moreover, niacin attenuated oxLDL-induced apoptosis of HUVECs as well. In addition, niacin significantly lessened lipid deposition in arterial wall, increased HDL-C and apoA levels and decreased TG and non-HDL-C levels in plasma, and upregulated the mRNA amount of cholesterol 7 α-hydroxylase A1 in liver of guinea pigs. These data suggest for the first time that niacin inhibits vascular inflammation in vivo and in vitro via downregulating NF-κB signaling pathway. Furthermore, niacin also modulates plasma lipid by upregulating the expression of factors involved in the process of reverse cholesterol transport.

  17. Inhibition of Rho protein stimulates iNOS expression in rat vascular smooth muscle cells.

    PubMed

    Muniyappa, R; Xu, R; Ram, J L; Sowers, J R

    2000-06-01

    Inducible nitric oxide synthase (iNOS) in vascular smooth muscle cells (VSMCs) is upregulated in arterial injury and plays a role in regulating VSMC proliferation and restenosis. Inflammatory cytokines [e.g., interleukin-1beta (IL-1beta)] released during vascular injury induce iNOS. Small GTP-binding proteins of the Ras superfamily play a major role in IL-1beta-dependent signaling pathways. In this study, we examined the role of Rho GTPases in regulating iNOS expression in VSMCs. Treatment of VSMCs with mevastatin, which inhibits isoprenylation of Rho and other small GTP-binding proteins, produced significantly higher amounts of IL-1beta-evoked NO and iNOS protein compared with control. Similarly, bacterial toxins [Toxin B from Clostridium difficile and C3 ADP-ribosyl transferase (C3) toxin from Clostridium botulinium] that specifically inactivate Rho proteins increased NOS products (NO and citrulline) and iNOS expression. Toxin B increased the activity of iNOS promoter-reporter construct in VSMCs. Both toxins enhanced IL-1beta-stimulated iNOS expression and NO production. These data demonstrate for the first time that inhibition of Rho induces iNOS and suggest a role for Rho protein in IL-1beta-stimulated NO production in VSMCs.

  18. Effect of magnesium on vascular reactivity in NOS inhibition-induced hypertension.

    PubMed

    Basralı, Filiz; Nasırcılar Ülker, Seher; Koçer, Günnur; Ülker Karadamar, Pınar; Özyurt, Dilek; Cengiz, Melike; Şentürk, Ümit Kemal

    2015-06-01

    This study investigated the effect of magnesium on the vascular reactivity of conduit and resistance arteries in a nitric oxide synthase inhibition-induced hypertension model. The aorta and third-order branches of the mesenteric artery were dissected from normotensive control and hypertensive rats, and their constriction and dilation responses in physiological saline solution containing normal (1.2 mM) or high (4.8 mM) magnesium concentrations were examined. The responses of the vessels were evaluated using potassium chloride (KCl) and phenylephrine (Phe), acetylcholine (ACh) and sodium nitroprusside. The Phe-induced constriction response of the aortic rings increased, whereas the ACh-induced dilation response decreased, in the hypertensive group compared to controls, in the presence of a normal magnesium concentration. High magnesium did not alter these responses in either group. Both the KCl- and Phe-induced constriction responses of the mesenteric arteries increased, and the ACh-induced dilation response decreased in the hypertensive group compared to controls, in the presence of a normal magnesium concentration. High magnesium significantly decreased the KCl and Phe-induced constriction and increased the ACh-induced dilation response of the mesenteric arteries in the hypertensive group, while it did not alter these responses in controls. This study suggests that high magnesium improves vascular reactivity of resistance-, but not conduit-type arteries in the nitric oxide synthase inhibition-induced hypertension model.

  19. Niacin Inhibits Vascular Inflammation via Downregulating Nuclear Transcription Factor-κB Signaling Pathway

    PubMed Central

    Si, Yanhong; Zhang, Ying; Zhao, Jilong; Guo, Shoudong; Zhai, Lei; Yao, Shutong; Sang, Hui; Yang, Nana; Song, Guohua; Gu, Jue; Qin, Shucun

    2014-01-01

    The study aimed to investigate the effect of niacin on vascular inflammatory lesions in vivo and in vitro as well as its lipid-regulating mechanism. In vivo study revealed that niacin downregulated the levels of inflammatory factors (IL-6 and TNF-α) in plasma, suppressed protein expression of CD68 and NF-κB p65 in arterial wall, and attenuated oxidative stress in guinea pigs that have been fed high fat diet. In vitro study further confirmed that niacin decreased the secretion of IL-6 and TNF-α and inhibited NF-κB p65 and notch1 protein expression in oxLDL-stimulated HUVECs and THP-1 macrophages. Moreover, niacin attenuated oxLDL-induced apoptosis of HUVECs as well. In addition, niacin significantly lessened lipid deposition in arterial wall, increased HDL-C and apoA levels and decreased TG and non-HDL-C levels in plasma, and upregulated the mRNA amount of cholesterol 7α-hydroxylase A1 in liver of guinea pigs. These data suggest for the first time that niacin inhibits vascular inflammation in vivo and in vitro via downregulating NF-κB signaling pathway. Furthermore, niacin also modulates plasma lipid by upregulating the expression of factors involved in the process of reverse cholesterol transport. PMID:24991087

  20. Inhibiting post-translational core fucosylation prevents vascular calcification in the model of uremia.

    PubMed

    Wen, Xinyu; Liu, Anqi; Yu, Changqing; Wang, Lingyu; Zhou, Mengying; Wang, Nan; Fang, Ming; Wang, Weidong; Lin, Hongli

    2016-10-01

    Vascular calcification (VC) is an independent risk factor for cardiovascular disease and mortality in uremia. Post-translational core fucosylation is implicated in a number of pathological processes. First, we investigated the role of core fucosylation and key TGF-β1 pathway receptors in calcified arteries in vivo. To determine whether blocking core fucosylation effectively inhibited VC and TGF-β/Smad signaling pathway, we established an in vitro model of phosphate-induced calcification in rat vascular smooth muscle cells (VSMCs) to assess the role of core fucosylation in VC. Core fucose could be detected at markedly higher levels in calcified VSMCs than control cells. Fut8 (α-1,6 fucosyltransferase), the only enzyme responsible for core fucosylation in humans, was significantly upregulated by high phosphate. Exposed to high phosphate media and blocking core fucosylation in VSMCs by knocking down Fut8 using a siRNA markedly reduced calcium and phosphorus deposition and Cbfα1 expression (osteoblast-specific transcription factor), and increased α-Sma expression (smooth muscle cell marker). Fut8 siRNA significantly inhibited TGF-β/Smad2/3 signaling activation in VSMCs cultured in high phosphate media. In conclusion, this study provides evidence to suggest core fucosylation plays a major role in the process of VC and appropriate blockade of core fucosylation may represent a potential therapeutic strategy for treating VC in end-stage renal disease. Copyright © 2016. Published by Elsevier Ltd.

  1. Induction of Nur77 by hyperoside inhibits vascular smooth muscle cell proliferation and neointimal formation.

    PubMed

    Huo, Yan; Yi, Bing; Chen, Ming; Wang, Nadan; Chen, Pengguo; Guo, Cheng; Sun, Jianxin

    2014-12-15

    Nur77 is an orphan nuclear receptor that belongs to the nuclear receptor 4A (NR4A) subfamily, which has been implicated in a variety of biological events, such as cell apoptosis, proliferation, inflammation, and metabolism. Activation of Nur77 has recently been shown to be beneficial for the treatment of cardiovascular and metabolic diseases. The purpose of this study is to identify novel natural Nur77 activators and investigate their roles in preventing vascular diseases. By measuring Nur77 expression using quantitative RT-PCR, we screened active ingredients extracted from Chinese herb medicines with beneficial cardiovascular effects. Hyperoside (quercetin 3-D-galactoside) was identified as one of the potent activators for inducing Nur77 expression and activating its transcriptional activity in vascular smooth muscle cells (VSMCs). We demonstrated that hyperoside, in a time and dose dependent manner, markedly increased the expression of Nur77 in rat VSMCs, with an EC50 of ∼0.83 μM. Mechanistically, we found that hyperoside significantly increased the phosphorylation of ERK1/2 MAP kinase and its downstream target cAMP response element-binding protein (CREB), both of which contributed to the hyperoside-induced Nur77 expression in rat VSMCs. Moreover, through activation of Nur77 receptor, hyperoside markedly inhibited both vascular smooth muscle cell proliferation in vitro and the carotid artery ligation-induced neointimal formation in vivo. These findings demonstrate that hyperoside is a potent natural activator of Nur77 receptor, which can be potentially used for prevention and treatment of occlusive vascular diseases. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Inhibition of vascular remodelling in a porcine coronary injury model by herbal extract XS0601

    PubMed Central

    Xu, Hao; Shi, Dazhuo; Chen, Keji

    2006-01-01

    Background Arterial remodelling is a major pathologic change of restenosis after percutaneous coronary intervention (PCI). Our previous studies showed that XS0601 (consisting of Chuangxingol and paeoniflorin) had some effects on the prevention of restenosis after PCI. Therefore, the purpose of this study was to examine whether and how its mechanism was related to the regulation of the arterial remodelling after endothelial injury by balloon dilation. Methods Twenty Chinese mini-pigs were randomized into four groups: control, probucol, low-dose XS0601 and high-dose XS0601 group before oversized balloon injury of the left anterior descending coronary arteries. Starting from two days before balloon injury, the mini-pigs in the treated group were administered with probucol (2 g/day) and XS0601 (0.02 g/kg/day for low dose; 0.04 g/kg/day for high dose) for four weeks after balloon injury. The animals receiving balloon injury alone were used as control. Morphometric and angiographic analysis of the injured arteries were performed. Results The contribution of intimal hyperplasia and arterial remodelling to angiographic late lumen loss was 41% and 59% respectively. XS0601 markedly inhibited proliferation of smooth muscle cells (SMCs) and transformation of SMCs from contractile to synthetic phenotype in neointima, inhibited hyperplasia-related indices of morphometric analysis and reduce late angiographic lumen loss. The reduction of the late angiographic lumen loss resulting from vascular remodelling was greater after XS0601 treatment. Conclusion Both intimal hyperplasia and vascular remodelling are attributed to late lumen loss in this porcine coronary injury model. XS0601 markedly reduced angiographic late lumen loss resulting from intimal hyperplasia, vascular remodelling and XS0601 may be a potential agent to prevent restenosis after PCI. PMID:17302965

  3. 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.

  4. The Hippo pathway mediates inhibition of vascular smooth muscle cell proliferation by cAMP

    PubMed Central

    Kimura, Tomomi E.; Duggirala, Aparna; Smith, Madeleine C.; White, Stephen; Sala-Newby, Graciela B.; Newby, Andrew C.; Bond, Mark

    2016-01-01

    Aims Inhibition of vascular smooth muscle cell (VSMC) proliferation by intracellular cAMP prevents excessive neointima formation and hence angioplasty restenosis and vein-graft failure. These protective effects are mediated via actin-cytoskeleton remodelling and subsequent regulation of gene expression by mechanisms that are incompletely understood. Here we investigated the role of components of the growth-regulatory Hippo pathway, specifically the transcription factor TEAD and its co-factors YAP and TAZ in VSMC. Methods and results Elevation of cAMP using forskolin, dibutyryl-cAMP or the physiological agonists, Cicaprost or adenosine, significantly increased phosphorylation and nuclear export YAP and TAZ and inhibited TEAD-luciferase report gene activity. Similar effects were obtained by inhibiting RhoA activity with C3-transferase, its downstream kinase, ROCK, with Y27632, or actin-polymerisation with Latrunculin-B. Conversely, expression of constitutively-active RhoA reversed the inhibitory effects of forskolin on TEAD-luciferase. Forskolin significantly inhibited the mRNA expression of the pro-mitogenic genes, CCN1, CTGF, c-MYC and TGFB2 and this was reversed by expression of constitutively-active YAP or TAZ phospho-mutants. Inhibition of YAP and TAZ function with RNAi or Verteporfin significantly reduced VSMC proliferation. Furthermore, the anti-mitogenic effects of forskolin were reversed by overexpression of constitutively-active YAP or TAZ. Conclusion Taken together, these data demonstrate that cAMP-induced actin-cytoskeleton remodelling inhibits YAP/TAZ–TEAD dependent expression of pro-mitogenic genes in VSMC. This mechanism contributes novel insight into the anti-mitogenic effects of cAMP in VSMC and suggests a new target for intervention. PMID:26625714

  5. The Hippo pathway mediates inhibition of vascular smooth muscle cell proliferation by cAMP.

    PubMed

    Kimura, Tomomi E; Duggirala, Aparna; Smith, Madeleine C; White, Stephen; Sala-Newby, Graciela B; Newby, Andrew C; Bond, Mark

    2016-01-01

    Inhibition of vascular smooth muscle cell (VSMC) proliferation by intracellular cAMP prevents excessive neointima formation and hence angioplasty restenosis and vein-graft failure. These protective effects are mediated via actin-cytoskeleton remodelling and subsequent regulation of gene expression by mechanisms that are incompletely understood. Here we investigated the role of components of the growth-regulatory Hippo pathway, specifically the transcription factor TEAD and its co-factors YAP and TAZ in VSMC. Elevation of cAMP using forskolin, dibutyryl-cAMP or the physiological agonists, Cicaprost or adenosine, significantly increased phosphorylation and nuclear export YAP and TAZ and inhibited TEAD-luciferase report gene activity. Similar effects were obtained by inhibiting RhoA activity with C3-transferase, its downstream kinase, ROCK, with Y27632, or actin-polymerisation with Latrunculin-B. Conversely, expression of constitutively-active RhoA reversed the inhibitory effects of forskolin on TEAD-luciferase. Forskolin significantly inhibited the mRNA expression of the pro-mitogenic genes, CCN1, CTGF, c-MYC and TGFB2 and this was reversed by expression of constitutively-active YAP or TAZ phospho-mutants. Inhibition of YAP and TAZ function with RNAi or Verteporfin significantly reduced VSMC proliferation. Furthermore, the anti-mitogenic effects of forskolin were reversed by overexpression of constitutively-active YAP or TAZ. Taken together, these data demonstrate that cAMP-induced actin-cytoskeleton remodelling inhibits YAP/TAZ-TEAD dependent expression of pro-mitogenic genes in VSMC. This mechanism contributes novel insight into the anti-mitogenic effects of cAMP in VSMC and suggests a new target for intervention. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Atmospheric-pressure plasma-irradiation inhibits mouse embryonic stem cell differentiation to mesoderm and endoderm but promotes ectoderm differentiation

    NASA Astrophysics Data System (ADS)

    Miura, Taichi; Hamaguchi, Satoshi; Nishihara, Shoko

    2016-04-01

    Recently, various effects of low-temperature atmospheric-pressure plasma irradiation on living cells have been demonstrated, such as tissue sterilization, blood coagulation, angiogenesis, wound healing, and tumor elimination. However, the effect of plasma-irradiation on the differentiation of mouse embryonic stem cells (mESCs) has not yet been clarified. A large number of reactive species are generated by plasma-irradiation in medium, of which hydrogen peroxide (H2O2) is one of the main species generated. Here, we investigated the effect of plasma-irradiation on the differentiation of mESCs using an embryoid body (EB) formation assay with plasma-irradiated medium or H2O2-supplemented non-irradiated medium. Our findings demonstrated that plasma-irradiated medium potently inhibits the differentiation from mESCs to mesoderm and endoderm by inhibiting Wnt signaling as determined by quantitative polymerase chain reaction and immunoblotting analyses. In contrast, both the plasma-irradiated medium and H2O2-supplemented non-irradiated medium enhanced the differentiation to epiblastoid, ectodermal, and neuronal lineages by activation of fibroblast growth factor 4 (FGF4) signaling, suggesting that these effects are caused by the H2O2 generated by plasma-irradiation in medium. However, in each case, the differentiation to glial cells remained unaffected. This study is the first demonstration that plasma-irradiation affects the differentiation of mESCs by the regulation of Wnt and FGF4 signaling pathways.

  7. Pharmacological inhibition of PHOSPHO1 suppresses vascular smooth muscle cell calcification

    PubMed Central

    Kiffer-Moreira, Tina; Yadav, Manisha C; Zhu, Dongxing; Narisawa, Sonoko; Sheen, Campbell; Stec, Boguslaw; Cosford, Nicholas D.; Dahl, Russell; Farquharson, Colin; Hoylaerts, Marc. F.; MacRae, Vicky E.; Millán, José Luis

    2013-01-01

    Medial vascular calcification (MVC) is common in patients with chronic kidney disease, obesity, and aging. MVC is an actively regulated process that resembles skeletal mineralization, resulting from chondro-osteogenic transformation of vascular smooth muscle cells (VSMCs). Here, we used mineralizing murine VSMCs to study the expression of PHOSPHO1, a phosphatase that participates in the first step of matrix vesicles-mediated initiation of mineralization during endochondral ossification. Wild-type (WT) VSMCs cultured under calcifying conditions exhibited increased Phospho1 gene expression and Phospho1-/- VSMCs failed to mineralize in vitro. Using natural PHOSPHO1 substrates, potent and specific inhibitors of PHOSPHO1 were identified via high-throughput screening and mechanistic analysis and two, designated MLS-0390838 and MLS-0263839, were selected for further analysis. Their effectiveness in preventing VSMC calcification by targeting PHOSPHO1 function was assessed, alone and in combination with a potent tissue-nonspecific alkaline phosphatase (TNAP) inhibitor MLS-0038949. PHOSPHO1 inhibition by MLS-0263839 in mineralizing WT cells (cultured with added inorganic phosphate) reduced calcification in culture to 41.8% ± 2.0 of control. Combined inhibition of PHOSPHO1 by MLS-0263839 and TNAP by MLS-0038949 significantly reduced calcification to 20.9% ± 0.74 of control. Furthermore, the dual inhibition strategy affected the expression of several mineralization-related enzymes while increasing expression of the smooth muscle cell marker Acta2. We conclude that PHOSPHO1 plays a critical role in VSMC mineralization and that “phosphatase inhibition” may be a useful therapeutic strategy to reduce MVC. PMID:22887744

  8. Clopidogrel inhibition of stent, graft, and vascular thrombogenesis with antithrombotic enhancement by aspirin in nonhuman primates.

    PubMed

    Harker, L A; Marzec, U M; Kelly, A B; Chronos, N R; Sundell, I B; Hanson, S R; Herbert, J M

    1998-12-01

    A recent study showed that clopidogrel reduces thrombo-occlusive complications in patients with symptomatic atherosclerosis more effectively than aspirin. The effects of clopidogrel and aspirin have been compared, singly and in combination, for measurements of 111In-labeled platelets and 125I-labeled fibrin deposition in baboon models of arterial thrombosis and related to platelet aggregation and expression of activation epitopes induced by ADP, collagen, and thrombin receptor agonist peptide (TRAP) and to template bleeding times (BTs). Low-dose oral clopidogrel (0.2 mg. kg-1. d-1) produced cumulative (1) intermediate decreases in 111In-platelet and 125I-fibrin deposition for segments of prosthetic vascular graft, deployed endovascular metallic stents, and endarterectomized aorta (P<0.009 in all cases); (2) elimination of ADP-induced platelet aggregation (P<0.001); (3) modest inhibition of collagen-induced platelet aggregation (P<0.01); (4) no reduction in TRAP-induced platelet aggregation; and (5) minimal prolongation of BTs (P=0.03). High-dose oral clopidogrel (>/=2 mg/kg) produced the same effects within 3 hours. The effects of clopidogrel dissipated over 5 to 6 days. Aspirin 10 mg. kg-1. d-1 alone did not decrease 111In-platelet and 125I-fibrin deposition on segments of vascular graft but detectably decreased 111In-platelet and 125I-fibrin accumulation on stents (P<0.01), minimally inhibited ADP- and collagen-induced platelet aggregation (P<0.05 in both cases), and minimally prolonged BTs (P=0.004). Within 3 hours of aspirin administration, the antithrombotic effects of acute high-dose or chronic low-dose clopidogrel were substantially enhanced, and BTs were modestly prolonged without inhibiting platelet aggregation induced by TRAP (P<0.001 in all cases compared with clopidogrel alone). Clopidogrel produces irreversible, dose-dependent, intermediate reduction in thrombosis that is substantially enhanced by the addition of aspirin. The effects of combining

  9. Selective irradiation of the vascular endothelium has no effect on the survival of murine intestinal crypt stem cells

    PubMed Central

    Schuller, Bradley W.; Binns, Peter J.; Riley, Kent J.; Ma, Ling; Hawthorne, M. Frederick; Coderre, Jeffrey A.

    2006-01-01

    The possible role of vascular endothelial cell damage in the loss of intestinal crypt stem cells and the subsequent development of the gastrointestinal (GI) syndrome is addressed. Mice received whole-body epithermal neutron irradiation at a dose rate of 0.57 ± 0.04 Gy·min−1. An additional dose was selectively targeted to endothelial cells from the short-ranged (5–9 μm) particles released from neutron capture reactions in 10B confined to the blood by incorporation into liposomes 70–90 nm in diameter. Different liposome formulations produced 45 ± 7 or 118 ± 12 μg/g 10B in the blood at the time of neutron irradiation, which resulted in total absorbed dose rates in the endothelial cells of 1.08 ± 0.09 or 1.90 ± 0.16 Gy·min−1, respectively. At 3.5 d after irradiation, the intestinal crypt microcolony assay showed that the 2- to 3-fold increased doses to the microvasculature, relative to the nonspecific whole-body neutron beam doses, caused no additional crypt stem cell loss beyond that produced by the neutron beam alone. The threshold dose for death from the GI syndrome after neutron-beam-only irradiation was 9.0 ± 0.6 Gy. There were no deaths from the GI syndrome, despite calculated absorbed doses to endothelial cells as high as 27.7 Gy, in the groups that received neutron beam doses of <9.0 Gy with boronated liposomes in the blood. These data indicate that endothelial cell damage is not causative in the loss of intestinal crypt stem cells and the eventual development of the GI syndrome. PMID:16505359

  10. 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.

  11. Relative resistance to Mammalian target of rapamycin inhibition in vascular smooth muscle cells of diabetic donors.

    PubMed

    Lightell, Daniel J; Woods, T Cooper

    2013-01-01

    Diabetes mellitus is associated with an increased risk of cardiovascular disease. Intimal thickening, a component of cardiovascular disease, entails the proliferation and migration of vascular smooth muscle cells (VSMCs). Inhibition of the mammalian target of rapamycin (mTOR) blocks VSMC proliferation, in part through an increase in the cyclin-dependent kinase inhibitor, p27(Kip1). The use of mTOR inhibitors, such as rapamycin, is effective clinically in inhibiting intimal thickening. This efficacy is reduced in diabetic subjects, however, suggesting a change in the role of the mTOR pathway in intimal thickening under diabetic conditions. To examine whether diabetes induced changes in the role of mTOR in VSMC proliferation, we compared the response to rapamycin of human coronary artery VSMCs from diabetic (DM-huCASMC [human coronary artery smooth muscle cell]) and nondiabetic (ND-huCASMC) subjects. The DM-huCASMCs exhibited a relative resistance to rapamycin's inhibition of proliferation. Activation of the mTOR effector p70(S6kinase) was inhibited in rapamycin-treated DM-huCASMCs as in ND-huCASMCs. While ND-huCASMCs exhibited the normal increase in p27(Kip1) in response to rapamycin treatment, the DM-huCASMCs did not. Additionally, activation of the extracellular signal response kinase pathway was increased in the DM-huCASMCs, suggesting a potential pathway mediating the mTOR-independent decrease in p27(Kip1). We conclude that diabetes is accompanied by a relative resistance to the effects of mTOR inhibition on VSMC proliferation through a loss of mTOR's effects on p27(Kip1) levels. These data provide insight into the effects of insulin resistance on the role of mTOR in regulating intimal thickening.

  12. Inhibition of vascular peroxidase alleviates cardiac dysfunction and apoptosis induced by ischemia-reperfusion.

    PubMed

    Li, Ting-Ting; Zhang, Yi-Shuai; He, Lan; Liu, Bin; Shi, Rui-Zheng; Zhang, Guo-Gang; Peng, Jun

    2012-07-01

    Myeloperoxidase (MPO) is involved in myocardial ischemia-reperfusion (IR) injury and vascular peroxidase (VPO) is a newly identified isoform of MPO. This study was conducted to explore whether VPO is involved in IR-induced cardiac dysfunction and apoptosis. In a rat Langendorff model of myocardial IR, the cardiac function parameters (left ventricular pressure and the maximum derivatives of left ventricular pressure and coronary flow), creatine kinase (CK) activity, apoptosis, VPO1 activity were measured. In a cell (rat-heart-derived H9c2 cells) model of hypoxia-reoxygenation (HR), apoptosis, VPO activity, and VPO1 mRNA expression were examined. In isolated heart, IR caused a marked decrease in cardiac function and a significant increase in apoptosis, CK, and VPO activity. These effects were attenuated by pharmacologic inhibition of VPO. In vitro, pharmacologic inhibition of VPO activity or silencing of VPO1 expression significantly suppressed HR-induced cellular apoptosis. Our results suggest that increased VPO activity contributes to IR-induced cardiac dysfunction and inhibition of VPO activity may have the potential clinical value in protecting the myocardium against IR injury.

  13. 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.

  14. Local inhibition of converting enzyme and vascular responses to angiotensin and bradykinin in the human forearm.

    PubMed Central

    Benjamin, N; Cockcroft, J R; Collier, J G; Dollery, C T; Ritter, J M; Webb, D J

    1989-01-01

    1. The function of angiotensin converting enzyme was investigated in twenty-four healthy men. Forearm blood flow was measured under basal conditions and during administration of enalaprilat (a converting enzyme inhibitor) and/or peptide substrates of converting enzyme into the left brachial artery. Blood flow was compared in the two arms. 2. Enalaprilat had no effect on basal blood flow. The concentration of enalaprilat in venous blood from the control arm was low, and plasma renin activity was not increased, indicating that systemic inhibition of converting enzyme did not occur. 3. Effects of angiotensin and of bradykinin, administered intra-arterially, were limited to the infused arm. Enalaprilat (13 nmol min-1) inhibited converting enzyme in the infused arm, in which it caused approximately a 100-fold reduction in sensitivity to angiotensin I, while having no effect on the vasoconstriction caused by angiotensin II. Enalaprilat increased vasodilatation caused by bradykinin. 4. Aspirin, an inhibitor of cyclo-oxygenase, did not inhibit vasodilatation caused by bradykinin whether infused alone or with enalaprilat, indicating that these responses are not mediated by prostaglandins. 5. We conclude that under basal conditions neither conversion of angiotensin I to angiotensin II nor degradation of bradykinin determines resistance vessel tone in the human forearm. Converting enzyme may affect vascular tone in situations in which intravascular concentrations of peptides are increased over those present under basal conditions. PMID:2557432

  15. 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.

  16. Thread Embedding Acupuncture Inhibits Ultraviolet B Irradiation-Induced Skin Photoaging in Hairless Mice

    PubMed Central

    Kim, Yoon-Jung; Kim, Ha-Neui; Shin, Mi-Sook; Choi, Byung-Tae

    2015-01-01

    Thread embedding acupuncture (TEA) is an acupuncture treatment applied to many diseases in Korean medical clinics because of its therapeutic effects by continuous stimulation to tissues. It has recently been used to enhance facial skin appearance and antiaging, but data from evidence-based medicine are limited. To investigate whether TEA therapy can inhibit skin photoaging by ultraviolet B (UVB) irradiation, we performed analyses for histology, histopathology, in situ zymography and western blot analysis in HR-1 hairless mice. TEA treatment resulted in decreased wrinkle formation and skin thickness (Epidermis; P = 0.001 versus UV) in UVB irradiated mice and also inhibited degradation of collagen fibers (P = 0.010 versus normal) by inhibiting proteolytic activity of gelatinase matrix-metalloproteinase-9 (MMP-9). Western blot data showed that activation of c-Jun N-terminal kinase (JNK) induced by UVB (P = 0.002 versus normal group) was significantly inhibited by TEA treatment (P = 0.005 versus UV) with subsequent alleviation of MMP-9 activation (P = 0.048 versus UV). These results suggest that TEA treatment can have anti-photoaging effects on UVB-induced skin damage by maintenance of collagen density through regulation of expression of MMP-9 and related JNK signaling. Therefore, TEA therapy may have potential roles as an alternative treatment for protection against skin damage from aging. PMID:26185518

  17. Protective Role of Sodium-Glucose Co-Transporter 2 Inhibition Against Vascular Complications in Diabetes.

    PubMed

    Yamagishi, Sho-ichi; Matsui, Takanori

    2016-04-01

    Diabetic micro- and macroangiopathy are devastating vascular complications that could account for disabilities and high mortality rate in patients with diabetes. Indeed, diabetic nephropathy and retinopathy are the leading causes of end-stage renal failure and acquired blindness, respectively, and atherosclerotic cardiovascular diseases (CVD) accounts for about 60% of death in diabetic subjects. As a result, the average life span of diabetic patients is about 10-15 years shorter than that of non-diabetic subjects. Furthermore, tight blood glucose control might have no more than a marginal impact on CVD in general and on all-cause mortality in particular in diabetes. Therefore, therapeutic strategies that target vascular complications in diabetes need to be developed. Recently, selective inhibition of sodium-glucose co-transporter 2 (SGLT2) has been proposed as a potential therapeutic target for the treatment of patients with diabetes because of low risk of hypoglycemia and no weight gain. Because 90% of glucose filtered by the glomerulus is reabsorbed by a low-affinity/high-capacity SGLT2 expressed in the S1 and S2 segments of the proximal tubule, blockade of SGLT2 promotes urinary glucose excretion and as a result improves hyperglycemia in an insulin-independent manner. Moreover, we have shown that SGLT2-mediated glucose overload to tubular cells could elicit inflammatory and pro-apoptotic reactions in this cell, being directly involved in diabetic nephropathy. In addition, several clinical studies have also shown that SGLT2 inhibitors could reduce blood pressure, body weight, and serum uric acid levels and ameliorate cardiovascular risk in patients with diabetes. This review summarizes the pathophysiological role of SGLT2 in vascular complications in diabetes and its potential therapeutic interventions.

  18. Lanthanum acetate inhibits vascular calcification induced by vitamin D3 plus nicotine in rats.

    PubMed

    Zhou, Ye-Bo; Jin, Shao-Ju; Cai, Yan; Teng, Xu; Chen, Li; Tang, Chao-Shu; Qi, Yong-Fen

    2009-08-01

    Lanthanum, a rare earth element, has been used to decrease serum phosphorus level in patients with chronic renal disease and hyperphosphatemia. We aimed to observe the effect and mechanism of two doses of lanthanum acetate (375 and 750 mg/kg/day) on vascular calcification induced by vitamin D3 plus nicotine treatment in rats for 4 weeks. As compared with control rats, rats with calcification showed widespread calcified nodules and irregular elastic fibers in calcified aorta on von Kossa calcium staining and increased aortic calcium and phosphorus contents, alkaline phosphatase (ALP) activity and bone-related protein expressions for osteopontin (OPN) and type III sodium dependent phosphate cotransporter Pit-1 (Pit-1). After treatment with either dose of lanthanum acetate, the calcified nodules and degree of irregular elastic fibers decreased in aortas. Lanthanum acetate at 750 mg/kg/day was more effective than 375 mg/kg/day in lessening vascular calcification by significantly reducing plasma phosphorus level, calcium x phosphorus product and ALP activity, by 30.3%, 28.6%, and 68.6%, respectively; reducing aortic phosphorus and calcium contents and ALP activity, by 48%, 53.1%, and 63.5% (all P < 0.01), respectively; reducing aortic mRNA level of OPN and Pit-1, by 55.8% (P < 0.01) and 38.8% (P < 0.05) and protein level of OPN and Pit-1, by 37.2% and 27.2% (both P < 0.01), respectively; and increasing carboxylated matrix Gla-protein (MGP) protein expression by 33.7% (P < 0.05), as compared with rats treated with vitamin D3 and nicotine alone. Lanthanum acetate could effectively inhibit the pathogenesis of vascular calcification.

  19. Effect of Previous Irradiation on Vascular Thrombosis of Microsurgical Anastomosis: A Preclinical Study in Rats.

    PubMed

    Barrera-Ochoa, Sergi; Gallardo-Calero, Irene; López-Fernández, Alba; Romagosa, Cleofe; Vergés, Ramona; Aguirre-Canyadell, Marius; Soldado, Francisco; Velez, Roberto

    2016-11-01

    The objective of the present investigation was to compare the effect of neoadjuvant irradiation on the microvascular anastomosis in cervical bundle using an experimental model in rats. One hundred forty male Sprague-Dawley rats were allocated into 4 groups: group I, control, arterial microanastomosis; group II, control, venous microanastomosis; group III, arterial microanastomosis with previous irradiation (20 Gy); and group IV, venous microanastomosis with previous irradiation (20 Gy). Clinical parameters, technical values of anastomosis, patency, and histopathological parameters were evaluated. Irradiated groups (III and IV) and vein anastomosis groups (II and IV) showed significantly increased technical difficulties. Group IV showed significantly reduced patency rates (7/35) when compared with the control group (0/35). Radiotherapy significantly decreased the patency rates of the vein (7/35) when compared with the artery (1/35). Groups III and IV showed significantly reduced number of endothelial cells and also showed the presence of intimal thickening and adventitial fibrosis as compared with the control group. Neoadjuvant radiotherapy reduces the viability of the venous anastomosis in a preclinical rat model with a significant increase in the incidence of vein thrombosis.

  20. Effect of Previous Irradiation on Vascular Thrombosis of Microsurgical Anastomosis: A Preclinical Study in Rats

    PubMed Central

    Gallardo-Calero, Irene; López-Fernández, Alba; Romagosa, Cleofe; Vergés, Ramona; Aguirre-Canyadell, Marius; Soldado, Francisco; Velez, Roberto

    2016-01-01

    Background: The objective of the present investigation was to compare the effect of neoadjuvant irradiation on the microvascular anastomosis in cervical bundle using an experimental model in rats. Methods: One hundred forty male Sprague–Dawley rats were allocated into 4 groups: group I, control, arterial microanastomosis; group II, control, venous microanastomosis; group III, arterial microanastomosis with previous irradiation (20 Gy); and group IV, venous microanastomosis with previous irradiation (20 Gy). Clinical parameters, technical values of anastomosis, patency, and histopathological parameters were evaluated. Results: Irradiated groups (III and IV) and vein anastomosis groups (II and IV) showed significantly increased technical difficulties. Group IV showed significantly reduced patency rates (7/35) when compared with the control group (0/35). Radiotherapy significantly decreased the patency rates of the vein (7/35) when compared with the artery (1/35). Groups III and IV showed significantly reduced number of endothelial cells and also showed the presence of intimal thickening and adventitial fibrosis as compared with the control group. Conclusion: Neoadjuvant radiotherapy reduces the viability of the venous anastomosis in a preclinical rat model with a significant increase in the incidence of vein thrombosis. PMID:27975009

  1. Inhibition of converting enzyme and neointima formation after vascular injury in rabbits and guinea pigs.

    PubMed

    Clozel, J P; Hess, P; Michael, C; Schietinger, K; Baumgartner, H R

    1991-10-01

    Recently, it has been shown that cilazapril could suppress neointima formation after vascular injury in rats. The goal of the present study was to confirm these findings in guinea pigs and rabbits. Vascular injury was produced by ballooning the right carotid artery of guinea pigs and the right iliac artery of rabbits. The animals were treated with either placebo or cilazapril (30 mg/kg/day and 3 mg/kg/day in guinea pigs and rabbits, respectively). Cilazapril decreased by 42% (p less than 0.001) the neointima area in the guinea pig but was ineffective in rabbits. However, in rabbits, doses of cilazapril higher than 3 mg/kg could not be given because of known toxicological effects in the rabbit. We conclude that the protective effect of cilazapril described in rats also is observed in guinea pigs. However, in rabbits, the maximal tolerated dose of cilazapril was ineffective. These results underline the importance of ongoing clinical studies to evaluate if, in humans, cilazapril inhibits restenosis after coronary angioplasty.

  2. The use of Intravenous Laser Blood Irradiation (ILBI) at 630–640 nm to prevent vascular diseases and to increase life expectancy

    PubMed Central

    2015-01-01

    Background and Aims: The mortality rate from vascular diseases is one of the highest. The use of Intravenous Laser Blood Irradiation (ILBI) within the last 30 years has demonstrated high efficacy in the treatment of vascular, cardiac and other systemic diseases. Rationale: Laser energy at 630-640 nanometers is arguably the most effective for irradiation of blood and the vascular wall. Photons at this wavelength are absorbed by oxygen, improve microcirculation, can change the viscosity of the blood and affect vascular endothelium. Conclusions: In summary, more than 25 years of experience of using laser energy at 630-640 nm has shown that this waveband directly influences the parameters of all cells in the blood, blood plasma, the coagulation process and all the structural components of the vascular wall. Additionally, ILBI directly or indirectly affects the cells of the immune system, hormones, and exchange processes in an organism, thereby not only improving the function of the vascular system, but also the other systems of an organism. It can finally lead to lower the incidence and number of vascular diseases, and indirectly to the reduction of the number of diseases in other organs and even systemically, thus helping to prolong the lifespan. PMID:25941421

  3. Piperlongumine inhibits atherosclerotic plaque formation and vascular smooth muscle cell proliferation by suppressing PDGF receptor signaling

    SciTech Connect

    Son, Dong Ju; Kim, Soo Yeon; Han, Seong Su; Kim, Chan Woo; Kumar, Sandeep; Park, Byeoung Soo; Lee, Sung Eun; Yun, Yeo Pyo; Jo, Hanjoong; Park, Young Hyun

    2012-10-19

    Highlights: Black-Right-Pointing-Pointer Anti-atherogenic effect of PL was examined using partial carotid ligation model in ApoE KO mice. Black-Right-Pointing-Pointer PL prevented atherosclerotic plaque development, VSMCs proliferation, and NF-{kappa}B activation. Black-Right-Pointing-Pointer Piperlongumine reduced vascular smooth muscle cell activation through PDGF-R{beta} and NF-{kappa}B-signaling. Black-Right-Pointing-Pointer PL may serve as a new therapeutic molecule for atherosclerosis treatment. -- Abstract: Piperlongumine (piplartine, PL) is an alkaloid found in the long pepper (Piper longum L.) and has well-documented anti-platelet aggregation, anti-inflammatory, and anti-cancer properties; however, the role of PL in prevention of atherosclerosis is unknown. We evaluated the anti-atherosclerotic potential of PL in an in vivo murine model of accelerated atherosclerosis and defined its mechanism of action in aortic vascular smooth muscle cells (VSMCs) in vitro. Local treatment with PL significantly reduced atherosclerotic plaque formation as well as proliferation and nuclear factor-kappa B (NF-{kappa}B) activation in an in vivo setting. PL treatment in VSMCs in vitro showed inhibition of migration and platelet-derived growth factor BB (PDGF-BB)-induced proliferation to the in vivo findings. We further identified that PL inhibited PDGF-BB-induced PDGF receptor beta activation and suppressed downstream signaling molecules such as phospholipase C{gamma}1, extracellular signal-regulated kinases 1 and 2 and Akt. Lastly, PL significantly attenuated activation of NF-{kappa}B-a downstream transcriptional regulator in PDGF receptor signaling, in response to PDGF-BB stimulation. In conclusion, our findings demonstrate a novel, therapeutic mechanism by which PL suppresses atherosclerosis plaque formation in vivo.

  4. Cortistatin inhibits calcification of vascular smooth muscle cells by depressing osteoblastic differentiation and endoplasmic reticulum stress.

    PubMed

    Liu, Yue; Lin, Fang; Fu, Yu; Chen, Wenjia; Liu, Wenxiu; Chi, Jinyu; Zhang, Xiaohui; Yin, Xinhua

    2016-11-01

    Accumulating evidence has indicated that vascular smooth muscular cells (VSMCs) play an important role in the development of vascular calcification (VC). Cortistatin (CST), a novel bio-active peptide, has been shown to exert multiple protective effects on the cardiovascular system. However, the role and possible mechanism of CST in VC remain unclear. Therefore, we used β-glycerophosphoric acid (β-GP) to induce calcification in rat and human VSMCs to determine the effects of CST on osteoblastic differentiation and VSMC mineralization in vitro. Compared with the control, β-GP significantly increased alkaline phosphatase (ALP) activity and calcium content in cultured rat and human VSMCs, as well as multicellular node formation and calcium deposition, as confirmed by von Kossa and Alizarin Red S staining assays. After incubating rat and human VSMCs with β-GP in the presence of different doses of CST (10(-8) or 10(-7) mol/L), CST clearly reversed the β-GP-induced increases in ALP activity and calcium content and formation of pathological calcified nodes of VSMCs in a dose-independent manner. Moreover, 10(-8) and 10(-7) mol/L CST inhibited the phenotypic transformation of VSMCs into osteoblastic cells by decreasing the osteocalcin protein levels, increasing the SM-α-actin protein levels, and reducing endoplasmic reticulum stress by decreasing the protein expression of glucose-regulated protein 94 and CCAAT/enhancer-binding protein homologous protein. In conclusion, CST directly inhibited β-GP-induced calcification of VSMCs in vitro, probably by suppressing ERS and phenotypic transformation of VSMCs into osteoblastic cells. These results indicate that CST represents a potential target for the prevention and treatment of VC.

  5. T3 inhibits the calcification of vascular smooth muscle cells and the potential mechanism

    PubMed Central

    Chang, Xiaodan; Zhang, Baohong; Lihua, Li; Feng, Zhichun

    2016-01-01

    Objective: This study aimed to investigate the potential molecular mechanism underlying the T3 induced vascular calcification and phenotype transformation of vascular smooth muscle cells (VSMCs). Methods: Rat thoracic aortic smooth muscle cells (A7r5) were cultured in vitro and randomly assigned into normal control group, calcification group, T3 group and inhibitor group. Results: When compared with normal control group, the osteocalcin content, ALP activity, Osterix and Runx2 mRNA expression and OPN protein expression increased significantly (P<0.01), and the protein expression of SMα and SM22α reduced dramatically in A7r5 cells of calcification group (P<0.01). After T3 treatment, the osteocalcin content and ALP activity reduced markedly, mRNA expression of Osterix and Runx2 and OPN protein expression reduced significantly. However, MMI (inhibitor of T3) was able to block the above effects of T3. When compared with calcification group, Osterix and Runx2 mRNA expression and OPN protein expression increased markedly (P<0.01). In addition, the protein expression of ERK1/2, p-ERK, Akt and p-Akt increased significantly in calcification group. In the presence of integrin αvβ3/ERK blocker (PD98059) and/or PI3K/Akt antagonist (LY294002), T3 was still able to inhibit the calcification, and this effect was similar to that after treatment with inhibitors alone. Moreover, LY294002 had a better inhibitory effect as compared to PD98059. Conclusion: T3 may act on PI3K/Akt signaling pathway to inhibit the phenotype transformation of VSMC, which then suppresses the calcium/phosphate induced calcification of rat VSMCs. Thus, T3 is an endogenous molecule that can protect the blood vessels against calcification. PMID:27904672

  6. Inhibiting the repair of DNA damage induced by gamma irradiation in rat thymocytes

    SciTech Connect

    Smit, J.A.; Stark, J.H.

    1994-01-01

    This study assessed the ability of 11 established and potential radiosensitizing agents to retard the repair of radiation-induced DNA damage with a view to enhancing the immunosuppressive effects of in vivo lymphoid irradiation. The capability of irradiated rat thymocytes to repair DNA damage was assessed by an adaptation of the fluorimetric unwinding method. Three compounds, 3-aminobenzamide (3-AB), novobiocin and flavone-8-acetic acid (FAA), inhibited repair significantly. We also report the effect of low-dose irradiation combined with repair inhibitors on the relationship between DNA strand breaks, fragmentation, cell viability and use of nicotinamide adenine dinucleotide (NAD). DNA fragmentation was increased by 1 mM/l FAA, 1 mM/l novobiocin and 50 {mu}M/l RS-61443 within 3 h of incubation. The latter two compounds also proved cytotoxic. All three drugs augmented the effect of ionizing radiation on the use of NAD. Of the agents investigated, FAA showed the most promise for augmenting the immunosuppressive action of irradiation at nontoxic, pharmacokinetically achievable concentrations. 33 refs., 1 fig., 2 tabs.

  7. Localized CT-Guided Irradiation Inhibits Neurogenesis in Specific Regions of the Adult Mouse Brain

    PubMed Central

    Ford, E. C.; Achanta, P.; Purger, D.; Armour, M.; Reyes, J.; Fong, J.; Kleinberg, L.; Redmond, K.; Wong, J.; Jang, M. H.; Jun, H.; Song, H-J.; Quinones-Hinojosa, A.

    2011-01-01

    Radiation is used in the study of neurogenesis in the adult mouse both as a model for patients undergoing radiation therapy for CNS malignancies and as a tool to interrupt neurogenesis. We describe the use of a dedicated CT-guided precision device to irradiate specific sub-regions of the adult mouse brain. Improved CT visualization was accomplished with intrathecal injection of iodinated contrast agent, which enhances the lateral ventricles. T2-weighted MRI images were also used for target localization. Visualization of delivered beams (10 Gy) in tissue was accomplished with immunohistochemical staining for the protein γ-H2AX, a marker of DNA double-strand breaks. γ-H2AX stains showed that the lateral ventricle wall could be targeted with an accuracy of 0.19 mm (n = 10). In the hippocampus, γ-H2AX staining showed that the dentate gyrus can be irradiated unilaterally with a localized arc treatment. This resulted in a significant decrease of proliferative neural progenitor cells as measured by Ki-67 staining (P < 0.001) while leaving the contralateral side intact. Two months after localized irradiation, neurogenesis was significantly inhibited in the irradiated region as seen with EdU/NeuN double labeling (P < 0.001). Localized radiation in the rodent brain is a promising new tool for the study of neurogenesis. PMID:21449714

  8. Inhibition of Escherichia coli respiratory enzymes by short visible femtosecond laser irradiation

    NASA Astrophysics Data System (ADS)

    Lu, Chieh-Han; Lin, Kung-Hsuan; Hsu, Yung-Yuan; Tsen, Kong-Thon; Kuan, Yung-Shu

    2014-08-01

    A visible femtosecond laser is shown to be capable of selectively inactivating a wide spectrum of microorganisms in a wavelength and pulse width dependent manner. However, the mechanism of how a visible femtosecond laser affects the viability of different microorganisms is still elusive. In this paper, the cellular surface properties, membrane integrity and metabolic rate of Escherichia coli (E. coli) irradiated by a visible femtosecond laser (λ = 415 nm, pulse width = 100 fs) with different exposure times were investigated. Our results showed that femtosecond laser treatment for 60 min led to cytoplasmic leakage, protein aggregation and alternation of the physical properties of the E. coli cell membrane. In comparison, a 10 min exposure of bacteria to femtosecond laser irradiation induced an immediate reduction of 75% in the glucose-dependent respiratory rate, while the cytoplasmic leakage was not detected. Results from enzymatic assays showed that oxidases and dehydrogenases involved in the E. coli respiratory chain exhibited divergent susceptibility after laser irradiation. This early commencement of respiratory inhibition after a short irradiation is presumed to have a dominant effect on the early stage of bacteria inactivation.

  9. Carbon Ion Irradiation Inhibits Glioma Cell Migration Through Downregulation of Integrin Expression

    SciTech Connect

    Rieken, Stefan; Habermehl, Daniel; Wuerth, Lena; Brons, Stephan; Mohr, Angela; Lindel, Katja; Weber, Klaus; Haberer, Thomas; Debus, Juergen; Combs, Stephanie E.

    2012-05-01

    Purpose: To investigate the effect of carbon ion irradiation on glioma cell migration. Methods and Materials: U87 and Ln229 glioma cells were irradiated with photons and carbon ions. Migration was analyzed 24 h after irradiation. Fluorescence-activated cell sorting analysis was performed in order to quantify surface expression of integrins. Results: Single photon doses of 2 Gy and 10 Gy enhanced {alpha}{sub {nu}}{beta}{sub 3} and {alpha}{sub {nu}}{beta}{sub 5} integrin expression and caused tumor cell hypermigration on both vitronectin (Vn) and fibronectin (Fn). Compared to integrin expression in unirradiated cells, carbon ion irradiation caused decreased integrin expression and inhibited cell migration on both Vn and Fn. Conclusion: Photon radiotherapy (RT) enhances the risk of tumor cell migration and subsequently promotes locoregional spread via photon induction of integrin expression. In contrast to photon RT, carbon ion RT causes decreased integrin expression and suppresses glioma cell migration on both Vn and Fn, thus promising improved local control.

  10. Thrombomodulin Induces a Quiescent Phenotype and Inhibits Migration in Vascular Smooth Muscle Cells In Vitro.

    PubMed

    Bass, Heather M; Beard, Richard S; Cha, Byeong J; Yuan, Sarah Y; Nelson, Peter R

    2016-01-01

    Loss of critical endothelial cell function and subsequent vascular smooth muscle cell (VSMC) migration is central to the pathology of injury-induced neointimal hyperplasia and recurrent stenosis. Thrombomodulin (TM), well known for its function as an endothelial surface anticoagulant, may have an unknown direct effect on VSMC physiology that would be lost after injury. Here, we examined a novel effect of TM on VSMC by testing the hypothesis that direct application of TM induces favorable changes to the morphology of VSMC and inhibits their migration. Primary human VSMC were harvested using the explant technique and used in early passage (1-4) for all experiments. Laser-scanning confocal fluorescent imaging was performed to assess the effect of soluble TM on VSMC morphology. In vitro, migration of VSMC was measured using: (1) a 4-hr modified Boyden chemotaxis assay and (2) a 24-hr electric cell-substrate impedance sensing injury migration assay. Migration experiments were conducted with VSMC exposed to increasing doses of soluble recombinant TM. Recombinant thrombin served as a positive control and serum-free media as a negative control for all experimentation. Data were analyzed using a Student's t-test or repeated measures analysis of variance where appropriate (α < 0.05). VSMC exposed to TM clearly demonstrated a quiescent morphology with organized stress fibers consistent with a quiescent, differentiated, contractile phenotype; whereas, thrombin stimulation led to an activated, dedifferentiated, synthetic phenotype. VSMC demonstrated a low, baseline level of migration in unstimulated serum-free conditions. Thrombin significantly stimulated VSMC migration as expected. TM, independent of thrombin, significantly inhibited baseline VSMC migration in a dose-response fashion. The maximal inhibition was observed at (5 μg/mL) with 70% reduction (56 ± 1.7 vs. 18 ± 3.5 cells/5 high-power fields, P = 0.0005). TM has a direct effect on VSMC resulting in a quiescent

  11. Troglitazone inhibits mitogenic signaling by insulin in vascular smooth muscle cells.

    PubMed

    Goetze, S; Kim, S; Xi, X P; Graf, K; Yang, D C; Fleck, E; Meehan, W P; Hsueh, W A; Law, R E

    2000-05-01

    Troglitazone (TRO) is an oral insulin-sensitizer that has direct effects on the vasculature to inhibit cell growth and migration. In vascular smooth muscle cells (VSMCs), insulin transduces a mitogenic signal that is dependent on the ERK1/2 MAP kinases. We examined the effects of TRO on this pathway and found that it inhibits mitogenic signaling. In quiescent VSMCs, insulin (1 microM) induced a 3.2-fold increase in DNA synthesis. TRO (1-20 microM) inhibited insulin-stimulated DNA synthesis by 72.8% at the maximal concentration. TRO at I and 10 microM had no significant effect on insulin-stimulated ERK1/2 activity. At 20 microM, however, TRO modestly enhanced insulin-stimulated ERK1/2 activity by 1.5-fold. ERKs transduce a mitogenic signal by phosphorylating transcription factors such as Elk-1. which regulate critical growth-response genes. We used GAL-Elk-1 expression plasmids to detect ERK-dependent activation of Elk-1. TRO at 1-20 microM potently inhibited insulin-stimulated, ERK1/2-dependent Elk-1 transcription factor activity. Neither early steps in insulin signaling nor the phosphatidylinositol 3-kinase (PI3K) branch of this pathway were affected by TRO, because it had no effect on IRS-1 phosphorylation, PI3K/IRS-1 association, or Akt phosphorylation. Because TRO is a known ligand for the nuclear transcription factor peroxisome proliferator-activated receptor gamma (PPARgamma), we tested two other ligands for this receptor, rosiglitazone (RSG) and 15-deoxy-delta12,14 prostaglandin J2 (15d-PGJ2). Both also inhibited insulin-induced DNA synthesis. In summary, these data show that TRO inhibits mitogenic signaling by insulin at a point distal of ERK1/2 activation, potentially by a PPARgamma-mediated inhibition of ERK-dependent phosphorylation and activation of nuclear transcription factors that regulate cell growth.

  12. Inhibition of Prostaglandin Transporter (PGT) Promotes Perfusion and Vascularization and Accelerates Wound Healing in Non-Diabetic and Diabetic Rats

    PubMed Central

    Liu, Zhongbo; Benard, Outhiriaradjou; Syeda, Mahrukh M.; Schuster, Victor L.; Chi, Yuling

    2015-01-01

    Peripheral ischemia, resulting from diminished arterial flow and defective local vascularization, is one of the main causes of impaired wound healing in diabetes. Vasodilatory prostaglandins (PGs), including PGE2 and PGI2, regulate blood flow in peripheral tissues. PGs also stimulate angiogenesis by inducing vascular endothelial growth factor. However, PG levels are reduced in diabetes mainly due to enhanced degradation. We hypothesized that inhibition of the prostaglandin transporter (PGT) (SLCO2A1), which mediates the degradation of PGs, would increase blood flow and stimulate vascularization, thereby mitigating peripheral ischemia and accelerating wound healing in diabetes. Here we report that inhibiting PGT with intravenously injected PGT inhibitor, T26A, increased blood flow in ischemic hind limbs created in non-diabetic rats and streptozotocin induced diabetic rats. Systemic, or combined with topical, T26A accelerated closure of cutaneous wounds. Immunohistochemical examination revealed that inhibition of PGT enhanced vascularization (marked by larger numbers of vessels formed by CD34+ cells), and accelerated re-epithelialization of cutaneous wounds. In cultured primary human bone marrow CD34+ cells and human epidermal keratinocytes (HEKs) either inhibiting or silencing PGT increased migration in both cell lines. Thus PGT directly regulates mobilization of endothelial progenitor cells (EPCs) and HEKs, which could contribute to PGT-mediated vascularization and re-epithelialization. At the molecular level, systemic inhibition of PGT raised circulating PGE2. Taken together, our data demonstrate that PGT modulates arterial blood flow, mobilization of EPCs and HEKs, and vascularization and epithelialization in wound healing by regulating vasodilatory and pro-angiogenic PGs. PMID:26230411

  13. 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.

  14. 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

  15. 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.

  16. Dipeptidyl Peptidase IV Inhibition Activates CREB and Improves Islet Vascularization through VEGF-A/VEGFR-2 Signaling Pathway

    PubMed Central

    Samikannu, Balaji; Chen, Chunguang; Lingwal, Neelam; Padmasekar, Manju; Engel, Felix B.; Linn, Thomas

    2013-01-01

    Substitution of pancreatic islets is a potential therapy to treat diabetes and it depends on reconstitution of islet’s capillary network. In this study, we addressed the question whether stabilization of Glucagon-Like-Peptide-1 (GLP-1) by inhibiting Dipeptidyl Peptidase-IV (DPP-IV) increases β-cell mass by modulating vascularization. Mouse or porcine donor islets were implanted under kidney capsule of diabetic mice treated with DPP-IV inhibitor sitagliptin. Grafts were analyzed for insulin production, β-cell proliferation and vascularization. In addition, the effect of sitagliptin on sprouting and Vascular Endothelial Growth Factor (VEGF)-A expression was examined ex vivo. The cAMP response element-binding (CREB) and VEGF-A/ Vascular Endothelial Growth Factor Receptor (VEGFR)-2 signaling pathway leading to islet vascularization was explored. Sitagliptin increased mean insulin content of islet grafts and area of insulin-positive tissue as well as β-cell proliferation. Interestingly, sitagliptin treatment also markedly increased endothelial cell proliferation, microvessel density and blood flow. Finally, GLP-1 (7-36) stimulated sprouting and VEGF expression, which was significantly enhanced by sitagliptin- mediated inhibition of DPP-IV. Our in vivo data demonstrate that sitagliptin treatment phosphorylated CREB and induced islet vascularization through VEGF-A/VEGFR-2 signaling pathway. This study paves a new pathway for improvement of islet transplantation in treating diabetes mellitus. PMID:24349326

  17. 3D Monte Carlo model of optical transport in laser-irradiated cutaneous vascular malformations

    NASA Astrophysics Data System (ADS)

    Majaron, Boris; Milanič, Matija; Jia, Wangcun; Nelson, J. S.

    2010-11-01

    We have developed a three-dimensional Monte Carlo (MC) model of optical transport in skin and applied it to analysis of port wine stain treatment with sequential laser irradiation and intermittent cryogen spray cooling. Our MC model extends the approaches of the popular multi-layer model by Wang et al.1 to three dimensions, thus allowing treatment of skin inclusions with more complex geometries and arbitrary irradiation patterns. To overcome the obvious drawbacks of either "escape" or "mirror" boundary conditions at the lateral boundaries of the finely discretized volume of interest (VOI), photons exiting the VOI are propagated in laterally infinite tissue layers with appropriate optical properties, until they loose all their energy, escape into the air, or return to the VOI, but the energy deposition outside of the VOI is not computed and recorded. After discussing the selection of tissue parameters, we apply the model to analysis of blood photocoagulation and collateral thermal damage in treatment of port wine stain (PWS) lesions with sequential laser irradiation and intermittent cryogen spray cooling.

  18. Losartan Inhibits Vascular Calcification by Suppressing the BMP2 and Runx2 Expression in Rats In Vivo.

    PubMed

    Li, Mincai; Wu, Panfeng; Shao, Juan; Ke, Zhiqiang; Li, Dan; Wu, Jiliang

    2016-04-01

    The blockade of renin-angiotensin II system has been shown to reduce morbidity and mortality in hypertension, atherosclerosis, diabetes and chronic kidney disease. Since vascular calcification (VC) is commonly found in these diseases, the aim of this study was to examine whether or not losartan, a widely used angiotensin II receptor blockers, inhibits VC in rats in vivo. A rat model of VC was generated by treating rats with a combination of warfarin and vitamin K1. Two weeks after the treatments, the rats were treated with vehicle or without losartan (100 ng/kg/day) for 2 weeks. At the end of the experiments, aortic arteries were isolated for the examination of calcification morphology, mRNA and protein expression of BMP2 and Runx2, and osteoblast differentiation. Warfarin and vitamin K instigated vascular remodeling with calcified plaques in the aortic arteries in rats. Losartan significantly attenuated warfarin- and vitamin K-induced vascular injury and calcification. Consistently, losartan suppressed the levels of mRNA and protein expression of BMP2 and Runx2, two key factors for VC. Further, vascular calcified lesion areas expressed angiotensin II 1 receptor (AT1R). Finally, losartan treatment significantly inhibited apoptosis in vascular smooth muscle cell (VSMC) in rat arteries. We conclude that losartan suppresses VC by lowering the expression of AT1R, Runx2 and BMP2, and by inhibiting the apoptosis of VSMC in rat aortic arteries.

  19. Low-power laser irradiation inhibits amyloid beta-induced cell apoptosis

    NASA Astrophysics Data System (ADS)

    Zhang, Heng; Wu, Shengnan

    2011-03-01

    The deposition and accumulation of amyloid-β-peptide (Aβ) in the brain are considered a pathological hallmark of Alzheimer's disease(AD). Apoptosis is a contributing pathophysiological mechanism of AD. Low-power laser irradiation (LPLI), a non-damage physical therapy, which has been used clinically for decades of years, is shown to promote cell proliferation and prevent apoptosis. Recently, low-power laser irradiation (LPLI) has been applied to moderate AD. In this study, Rat pheochromocytoma (PC12) cells were treated with amyloid beta 25-35 (Aβ25-35) for induction of apoptosis before LPLI treatment. We measured cell viability with CCK-8 according to the manufacture's protocol, the cell viability assays show that low fluence of LPLI (2 J/cm2 ) could inhibit the cells apoptosis. Then using statistical analysis of proportion of apoptotic cells by flow cytometry based on Annexin V-FITC/PI, the assays also reveal that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis. Taken together, we demonstrated that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis, these results directly point to a therapeutic strategy for the treatment of AD through LPLI.

  20. Neuroprotective effect of acute melatonin treatment on hippocampal neurons against irradiation by inhibition of caspase-3

    PubMed Central

    LI, JIANGUO; ZHANG, GUOWEI; MENG, ZHUANGZHI; WANG, LINGZHAN; LIU, HAIYING; LIU, QIANG; BUREN, BATU

    2016-01-01

    Neuronal cell apoptosis is associated with various factors that induce neurological damage, including radiation exposure. When administered prior to exposure to radiation, a protective agent may prevent cellular and molecular injury. The present study aimed to investigate whether melatonin exerts a neuroprotective effect by inhibiting the caspase cell death pathway. Male Sprague-Dawley rats were administered melatonin (100 mg/kg body weight) 30 min prior to radiation exposure in red light during the evening. In order to elucidate whether melatonin has a neuroprotective role, immunohistochemistry, terminal deoxynucleotidyl transferase dUTP nick-end labeling, Nissl staining, reverse transcription-quantitative polymerase chain reaction, reactive oxygen species analysis and western blotting were performed. At 24 h post-melatonin treatment, caspase-3 mRNA and protein expression levels were significantly decreased. These results demonstrated that melatonin may protect hippocampal neurons via the inhibition of caspase-3 when exposed to irradiation. Therefore, caspase-3 inhibition serves a neuroprotective and antioxidant role in the interventional treatment of melatonin. The results of the present study suggested that melatonin may have a potential therapeutic effect against irradiation; however, further studies are required in order to elucidate the underlying antioxidant mechanisms. PMID:27313671

  1. Monocyte prostaglandins inhibit procollagen secretion by human vascular smooth muscle cells: implications for plaque stability.

    PubMed

    Fitzsimmons, C; Proudfoot, D; Bowyer, D E

    1999-02-01

    Extracellular matrix remodelling occurs during atherosclerosis dictating the structure of the plaque and thus the resistance to rupture. Monocytes and macrophages are believed to play a role in this remodelling. In the present study, filter-separated co-culture has been used to study the effect of monocytes on procollagen turnover by human vascular smooth muscle cells (VSMC). In this system, freshly isolated human peripheral blood monocytes inhibited procollagen secretion from VSMC without affecting either degradation of procollagen, or DNA synthesis by the VSMC. Insertion of a 12 kDa dialysis membrane between the two cell types and treatment with indomethacin showed that the inhibitory factor was of low molecular weight and was cyclooxygenase-dependent. Pre-incubation of each cell type with indomethacin demonstrated that monocyte, but not VSMC cyclooxygenase was required. Thus, the inhibitory effect on procollagen secretion was due, most likely, to monocyte prostaglandins. Neither inhibition of thromboxane synthetase, nor blocking IL-1 activity, reduced the inhibitory activity. Addition of prostaglandins PGE1, PGE2 and PGF2alpha to VSMC cultures caused a reduction in procollagen secretion which was equivalent to, but was not additive with, the maximal effect achieved by monocytes. Monocytes and macrophages are a major source of prostaglandins and these molecules are likely to play an important role in collagen turnover within lesions.

  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. 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.

  5. 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.

  6. Prevention of vascular graft occlusion and thrombus-associated thrombin generation by inhibition of factor XI

    PubMed Central

    Tucker, Erik I.; Marzec, Ulla M.; White, Tara C.; Hurst, Sawan; Rugonyi, Sandra; McCarty, Owen J. T.; Gailani, David; Hanson, Stephen R.

    2009-01-01

    The protease thrombin is required for normal hemostasis and pathologic thrombogenesis. Since the mechanism of coagulation factor XI (FXI)–dependent thrombus growth remains unclear, we investigated the contribution of FXI to thrombus formation in a primate thrombosis model. Pretreatment of baboons with a novel anti–human FXI monoclonal antibody (aXIMab; 2 mg/kg) inhibited plasma FXI by at least 99% for 10 days, and suppressed thrombin-antithrombin (TAT) complex and β-thromboglobulin (βTG) formation measured immediately downstream from thrombi forming within collagen-coated vascular grafts. FXI inhibition with aXIMab limited platelet and fibrin deposition in 4-mm diameter grafts without an apparent increase in D-dimer release from thrombi, and prevented the occlusion of 2-mm diameter grafts without affecting template bleeding times. In comparison, pretreatment with aspirin (32 mg/kg) prolonged bleeding times but failed to prevent graft occlusion, supporting the concept that FXI blockade may offer therapeutic advantages over other antithrombotic agents in terms of bleeding complications. In whole blood, aXIMab prevented fibrin formation in a collagen-coated flow chamber, independent of factor XII and factor VII. These data suggest that endogenous FXI contributes to arterial thrombus propagation through a striking amplification of thrombin generation at the thrombus luminal surface. PMID:18945968

  7. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    SciTech Connect

    Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing; Glaves, Richard Samuel Elliot; Ash, David E.; Mohanty, Dillip K.

    2014-07-18

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well.

  8. Vascular changes in popliteal lymph nodes due to antigen challenge in normal and lethally irradiated mice

    SciTech Connect

    Steeber, D.A.; Erickson, C.M.; Hodde, K.C.; Albrecht, R.M.

    1987-06-01

    The microvascular system of the murine popliteal lymph node was investigated using scanning electron microscopy of microcorrosion casts. Time-dependent changes in the microvasculature following regional antigen challenge in normal and lymphocyte-depleted mice were studied. Normal lymph node microvasculature exhibited a significant increase in both the vascular bed and post-capillary venules containing high-endothelium in response to antigen challenge. Lymph nodes of lymphocyte-depleted mice showed no microvascular size increase following antigen challenge and a reduction in the amount of high-endothelium was observed.

  9. Antagonism of CD11b with Neutrophil Inhibitory Factor (NIF) Inhibits Vascular Lesions in Diabetic Retinopathy

    PubMed Central

    Veenstra, Alexander A.; Tang, Jie; Kern, Timothy S.

    2013-01-01

    Leukocytes and proteins that govern leukocyte adhesion to endothelial cells play a causal role in retinal abnormalities characteristic of the early stages of diabetic retinopathy, including diabetes-induced degeneration of retinal capillaries. Leukocyte integrin αmβ2 (CD11b/CD18, MAC1), a protein mediating adhesion, has been shown to mediate damage to endothelial cells by activated leukocytes in vitro. We hypothesized that Neutrophil Inhibitory Factor (NIF), a selective antagonist of integrin αmβ2, would inhibit the diabetes-induced degeneration of retinal capillaries by inhibiting the excessive interaction between leukocytes and retinal endothelial cells in diabetes. Wild type animals and transgenic animals expressing NIF were made diabetic with streptozotocin and assessed for diabetes-induced retinal vascular abnormalities and leukocyte activation. To assess if the leukocyte blocking therapy compromised the immune system, animals were challenged with bacteria. Retinal superoxide production, leukostasis and leukocyte superoxide production were increased in wild type mice diabetic for 10 weeks, as was the ability of leukocytes isolated from diabetic animals to kill retinal endothelial cells in vitro. Retinal capillary degeneration was significantly increased in wild type mice diabetic 40 weeks. In contrast, mice expressing NIF did not develop any of these abnormalities, with the exception that non-diabetic and diabetic mice expressing NIF generated greater amounts of superoxide than did similar mice not expressing NIF. Importantly, NIF did not significantly impair the ability of mice to clear an opportunistic bacterial challenge, suggesting that NIF did not compromise immune surveillance. We conclude that antagonism of CD11b (integrin αmβ2) by NIF is sufficient to inhibit early stages of diabetic retinopathy, while not compromising the basic immune response. PMID:24205223

  10. Antagonism of CD11b with neutrophil inhibitory factor (NIF) inhibits vascular lesions in diabetic retinopathy.

    PubMed

    Veenstra, Alexander A; Tang, Jie; Kern, Timothy S

    2013-01-01

    Leukocytes and proteins that govern leukocyte adhesion to endothelial cells play a causal role in retinal abnormalities characteristic of the early stages of diabetic retinopathy, including diabetes-induced degeneration of retinal capillaries. Leukocyte integrin αmβ2 (CD11b/CD18, MAC1), a protein mediating adhesion, has been shown to mediate damage to endothelial cells by activated leukocytes in vitro. We hypothesized that Neutrophil Inhibitory Factor (NIF), a selective antagonist of integrin αmβ2, would inhibit the diabetes-induced degeneration of retinal capillaries by inhibiting the excessive interaction between leukocytes and retinal endothelial cells in diabetes. Wild type animals and transgenic animals expressing NIF were made diabetic with streptozotocin and assessed for diabetes-induced retinal vascular abnormalities and leukocyte activation. To assess if the leukocyte blocking therapy compromised the immune system, animals were challenged with bacteria. Retinal superoxide production, leukostasis and leukocyte superoxide production were increased in wild type mice diabetic for 10 weeks, as was the ability of leukocytes isolated from diabetic animals to kill retinal endothelial cells in vitro. Retinal capillary degeneration was significantly increased in wild type mice diabetic 40 weeks. In contrast, mice expressing NIF did not develop any of these abnormalities, with the exception that non-diabetic and diabetic mice expressing NIF generated greater amounts of superoxide than did similar mice not expressing NIF. Importantly, NIF did not significantly impair the ability of mice to clear an opportunistic bacterial challenge, suggesting that NIF did not compromise immune surveillance. We conclude that antagonism of CD11b (integrin αmβ2) by NIF is sufficient to inhibit early stages of diabetic retinopathy, while not compromising the basic immune response.

  11. Drug packaging and delivery using perfluorocarbon nanoparticles for targeted inhibition of vascular smooth muscle cells

    PubMed Central

    Zhou, Zhao-xiong; Zhang, Bai-gen; Zhang, Hao; Huang, Xiao-zhong; Hu, Ya-li; Sun, Li; Wang, Xiao-min; Zhang, Ji-wei

    2009-01-01

    Aim: To investigate the in vitro release profile of drugs encapsulated within perfluorocarbon (PFC) nanoparticles (NPs) and their ability to inhibit the activity of vascular smooth muscle cells (SMCs). Methods: Dexamethasone phosphate (DxP) or dexamethasone acetate (DxA) was encapsulated into PFC nanoparticles using a high-pressure homogenous method. The morphology and size of the NPs were examined using scanning electron microscopy (SEM) and a laser particle size analyzer. Drug loading and in vitro release were assessed by high-performance liquid chromatography (HPLC). The impact of NP capsules on SMC proliferation, migration and apoptosis in vitro was assessed using cell counting kit-8, transwell cell migration and flow cytometry assays. Results: The sizes of DxP-NPs and DxA-NPs were 224±6 nm and 236±9 nm, respectively. The encapsulation efficiency (EE) of DxP-NPs was 66.4%±1.0%, with an initial release rate of 77.2%, whereas the EE of DxA-NPs was 95.3%±1.3%, with an initial release rate of 23.6%. Both of the NP-coated drugs could be released over 7 d. Human umbilical artery SMCs were harvested and cultured for four to six passages. Compared to free DxP, SMCs treated with tissue factor (TF)-directed DxP-NPs showed significant differences in the inhibition of proliferation, migration and apoptosis (P<0.05). Conclusion: The results collectively suggest that PFC nanoparticles will be beneficial for targeted drug delivery because of the sustained drug release and effective inhibition of SMC proliferation and migration. PMID:19890365

  12. Metformin inhibits inflammatory response via AMPK-PTEN pathway in vascular smooth muscle cells.

    PubMed

    Kim, Sun Ae; Choi, Hyoung Chul

    2012-09-07

    Atherosclerosis is a chronic inflammation of the coronary arteries. Vascular smooth muscle cells (VSMCs) stimulated by cytokines and chemokines accelerate the inflammatory response and migrate to the injured endothelium during the progression of atherosclerosis. Activation of AMP activated protein kinase (AMPK), a key sensor maintaining metabolic homeostasis, suppresses the inflammatory response. However, how AMPK regulates the inflammatory response is poorly understood. To identify the mechanism of this response, we focused on phosphatase and tensin homolog (PTEN), which is a negative regulator of inflammation. We investigated that activation of AMPK-induced PTEN expression and suppression of the inflammatory response through the AMPK-PTEN pathway in VSMCs. We treated with the well-known AMPK activator metformin to induce PTEN expression. PTEN was induced by metformin (2mM) and inhibited by compound C (10 μM) and AMPK siRNA. Tumor necrosis factor-alpha (TNF-α) was used to induce inflammation. The inflammatory response was confirmed by cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) expression, and activation of nuclear factor (NF)-κB. Metformin suppressed COX-2 and iNOS mRNA and protein expression dose dependently. Treatment with compound C and bpv (pic) in the presence of metformin, iNOS and COX-2 protein expression increased. NF-κB activation decreased in response to metformin and was restored by inhibiting AMPK and PTEN. Inhibiting AMPK and PTEN restored ROS levels stimulated with TNF-α. Taken together, PTEN could be a possible downstream regulator of AMPK, and the AMPK-PTEN pathway might be important in the regulation of the inflammatory response in VSMCs.

  13. Cinnamaldehyde inhibits L-type calcium channels in mouse ventricular cardiomyocytes and vascular smooth muscle cells.

    PubMed

    Alvarez-Collazo, Julio; Alonso-Carbajo, Lucía; López-Medina, Ana I; Alpizar, Yeranddy A; Tajada, Sendoa; Nilius, Bernd; Voets, Thomas; López-López, José Ramón; Talavera, Karel; Pérez-García, María Teresa; Alvarez, Julio L

    2014-11-01

    Cinnamaldehyde (CA), a major component of cinnamon, is known to have important actions in the cardiovascular system, including vasorelaxation and decrease in blood pressure. Although CA-induced activation of the chemosensory cation channel TRPA1 seems to be involved in these phenomena, it has been shown that genetic ablation of Trpa1 is insufficient to abolish CA effects. Here, we confirm that CA relaxes rat aortic rings and report that it has negative inotropic and chronotropic effects on isolated mouse hearts. Considering the major role of L-type Ca(2+) channels in the control of the vascular tone and cardiac contraction, we used whole-cell patch-clamp to test whether CA affects L-type Ca(2+) currents in mouse ventricular cardiomyocytes (VCM, with Ca(2+) as charge carrier) and in mesenteric artery smooth muscle cells (VSMC, with Ba(2+) as charge carrier). We found that CA inhibited L-type currents in both cell types in a concentration-dependent manner, with little voltage-dependent effects. However, CA was more potent in VCM than in VSMC and caused opposite effects on the rate of inactivation. We found these divergences to be at least in part due to the use of different charge carriers. We conclude that CA inhibits L-type Ca(2+) channels and that this effect may contribute to its vasorelaxing action. Importantly, our results demonstrate that TRPA1 is not a specific target of CA and indicate that the inhibition of voltage-gated Ca(2+) channels should be taken into account when using CA to probe the pathophysiological roles of TRPA1.

  14. The 18-kDa Translocator Protein Inhibits Vascular Cell Adhesion Molecule-1 Expression via Inhibition of Mitochondrial Reactive Oxygen Species

    PubMed Central

    Joo, Hee Kyoung; Lee, Yu Ran; Kang, Gun; Choi, Sunga; Kim, Cuk-Seong; Ryoo, Sungwoo; Park, Jin Bong; Jeon, Byeong Hwa

    2015-01-01

    Translocator protein 18 kDa (TSPO) is a mitochondrial outer membrane protein and is abundantly expressed in a variety of organ and tissues. To date, the functional role of TSPO on vascular endothelial cell activation has yet to be fully elucidated. In the present study, the phorbol 12-myristate 13-acetate (PMA, 250 nM), an activator of protein kinase C (PKC), was used to induce vascular endothelial activation. Adenoviral TSPO overexpression (10–100 MOI) inhibited PMA-induced vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1) expression in a dose dependent manner. PMA-induced VCAM-1 expressions were inhibited by Mito-TEMPO (0.1–0.5 μM), a specific mitochondrial antioxidants, and cyclosporin A (1–5 μM), a mitochondrial permeability transition pore inhibitor, implying on an important role of mitochondrial reactive oxygen species (ROS) on the endothelial activation. Moreover, adenoviral TSPO overexpression inhibited mitochondrial ROS production and manganese superoxide dismutase expression. On contrasts, gene silencing of TSPO with siRNA increased PMA-induced VCAM-1 expression and mitochondrial ROS production. Midazolam (1–50 μM), TSPO ligands, inhibited PMA-induced VCAM-1 and mitochondrial ROS production in endothelial cells. These results suggest that mitochondrial TSPO can inhibit PMA-induced endothelial inflammation via suppression of VCAM-1 and mitochondrial ROS production in endothelial cells. PMID:26608360

  15. d-alpha-tocopherol inhibition of vascular smooth muscle cell proliferation occurs at physiological concentrations, correlates with protein kinase C inhibition, and is independent of its antioxidant properties.

    PubMed

    Tasinato, A; Boscoboinik, D; Bartoli, G M; Maroni, P; Azzi, A

    1995-12-19

    d-alpha-Tocopherol, but not d-beta-tocopherol, negatively regulates proliferation of vascular smooth muscle cells at physiological concentrations. d-alpha-Tocopherol inhibits protein kinase C (PKC) activity, whereas d-beta-tocopherol is ineffective. Furthermore d-beta-tocopherol prevents the inhibition of cell growth and of PKC activity caused by d-alpha-tocopherol. The negative regulation by d-alpha-tocopherol of PKC activity appears to be the cause and not the effect of smooth muscle cell growth inhibition. d-alpha-Tocopherol does not act by binding to PKC directly but presumably by preventing PKC activation. It is concluded that, in vascular smooth muscle cells, d-alpha-tocopherol acts specifically through a nonantioxidant mechanism and exerts a negative control on a signal transduction pathway regulating cell proliferation.

  16. d-alpha-tocopherol inhibition of vascular smooth muscle cell proliferation occurs at physiological concentrations, correlates with protein kinase C inhibition, and is independent of its antioxidant properties.

    PubMed Central

    Tasinato, A; Boscoboinik, D; Bartoli, G M; Maroni, P; Azzi, A

    1995-01-01

    d-alpha-Tocopherol, but not d-beta-tocopherol, negatively regulates proliferation of vascular smooth muscle cells at physiological concentrations. d-alpha-Tocopherol inhibits protein kinase C (PKC) activity, whereas d-beta-tocopherol is ineffective. Furthermore d-beta-tocopherol prevents the inhibition of cell growth and of PKC activity caused by d-alpha-tocopherol. The negative regulation by d-alpha-tocopherol of PKC activity appears to be the cause and not the effect of smooth muscle cell growth inhibition. d-alpha-Tocopherol does not act by binding to PKC directly but presumably by preventing PKC activation. It is concluded that, in vascular smooth muscle cells, d-alpha-tocopherol acts specifically through a nonantioxidant mechanism and exerts a negative control on a signal transduction pathway regulating cell proliferation. Images Fig. 6 PMID:8618868

  17. Metformin inhibits inflammatory response via AMPK-PTEN pathway in vascular smooth muscle cells

    SciTech Connect

    Kim, Sun Ae; Choi, Hyoung Chul

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer PTEN was induced by metformin and inhibited by compound C and AMPK siRNA. Black-Right-Pointing-Pointer Metformin suppressed TNF-{alpha}-induced COX-2 and iNOS mRNA expression. Black-Right-Pointing-Pointer Compound C and bpv (pic) increased iNOS and COX-2 protein expression. Black-Right-Pointing-Pointer NF-{kappa}B activation was restored by inhibiting AMPK and PTEN. Black-Right-Pointing-Pointer AMPK and PTEN regulated TNF-{alpha}-induced ROS production in VSMCs. -- Abstract: Atherosclerosis is a chronic inflammation of the coronary arteries. Vascular smooth muscle cells (VSMCs) stimulated by cytokines and chemokines accelerate the inflammatory response and migrate to the injured endothelium during the progression of atherosclerosis. Activation of AMP activated protein kinase (AMPK), a key sensor maintaining metabolic homeostasis, suppresses the inflammatory response. However, how AMPK regulates the inflammatory response is poorly understood. To identify the mechanism of this response, we focused on phosphatase and tensin homolog (PTEN), which is a negative regulator of inflammation. We investigated that activation of AMPK-induced PTEN expression and suppression of the inflammatory response through the AMPK-PTEN pathway in VSMCs. We treated with the well-known AMPK activator metformin to induce PTEN expression. PTEN was induced by metformin (2 mM) and inhibited by compound C (10 {mu}M) and AMPK siRNA. Tumor necrosis factor-alpha (TNF-{alpha}) was used to induce inflammation. The inflammatory response was confirmed by cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) expression, and activation of nuclear factor (NF)-{kappa}B. Metformin suppressed COX-2 and iNOS mRNA and protein expression dose dependently. Treatment with compound C and bpv (pic) in the presence of metformin, iNOS and COX-2 protein expression increased. NF-{kappa}B activation decreased in response to metformin and was restored by inhibiting AMPK

  18. Inhibition of neointimal proliferation in rabbits after vascular injury by a single treatment with a protein adduct of nitric oxide.

    PubMed Central

    Marks, D S; Vita, J A; Folts, J D; Keaney, J F; Welch, G N; Loscalzo, J

    1995-01-01

    Endothelium-derived relaxing factor is important for vascular homeostasis and possesses qualities that may modulate vascular injury, including vasodilation, platelet inhibition, and inhibition of smooth muscle proliferation. S-nitrososerum albumin is a naturally occurring adduct of nitric oxide (NO) with a prolonged biologic half-life and is a potent vasodilator and platelet inhibitor. Given the avidity of serum albumin for subendothelial matrix and the antiproliferative effects of NO, we investigated the effects of locally delivered S-nitroso-bovine serum albumin (S-NO-BSA) and a polythiolated form of bovine serum albumin (pS-BSA) modified to carry several S-nitrosothiol groups (pS-NO-BSA) on neointimal responses in an animal model of vascular injury. Locally delivered S-NO-BSA bound preferentially to denuded rabbit femoral vessels producing a 26-fold increase in local concentration compared with uninjured vessels (P = 0.029). pS-NO-BSA significantly reduced the intimal/medial ratio (P = 0.038) and did so in conjunction with elevations in platelet (P < 0.001) and vascular cGMP content (P < or = 0.001). pS-NO-BSA treatment also inhibited platelet deposition (P = 0.031) after denuding injury. Comparison of BSA, S-NO-BSA, pS-NO-BSA, and control revealed a dose-response relationship between the amount of displaceable NO delivered and the extent of inhibition of neointimal proliferation at 2 wk (P < or = 0.001). Local administration of a stable protein S-nitrosothiol inhibits intimal proliferation and platelet deposition after vascular arterial balloon injury. This strategy for the local delivery of a long-lived NO adduct has potential for preventing restenosis after angioplasty. Images PMID:8675628

  19. Inhibition of vasculogenesis, but not angiogenesis, prevents the recurrence of glioblastoma after irradiation in mice.

    PubMed

    Kioi, Mitomu; Vogel, Hannes; Schultz, Geoffrey; Hoffman, Robert M; Harsh, Griffith R; Brown, J Martin

    2010-03-01

    Despite the high doses of radiation delivered in the treatment of patients with glioblastoma multiforme (GBM), the tumors invariably recur within the irradiation field, resulting in a low cure rate. Understanding the mechanism of such recurrence is therefore important. Here we have shown in an intracranial GBM xenograft model that irradiation induces recruitment of bone marrow-derived cells (BMDCs) into the tumors, restoring the radiation-damaged vasculature by vasculogenesis and thereby allowing the growth of surviving tumor cells. BMDC influx was initiated by induction of HIF-1 in the irradiated tumors, and blocking this influx prevented tumor recurrence. Previous studies have indicated that BMDCs are recruited to tumors in part through the interaction between the HIF-1-dependent stromal cell-derived factor-1 (SDF-1) and its receptor, CXCR4. Pharmacologic inhibition of HIF-1 or of the SDF-1/CXCR4 interaction prevented the influx of BMDCs, primarily CD11b+ myelomonocytes, and the postirradiation development of functional tumor vasculature, resulting in abrogation of tumor regrowth. Similar results were found using neutralizing antibodies against CXCR4. Our data therefore suggest a novel approach for the treatment of GBM: in addition to radiotherapy, the vasculogenesis pathway needs to be blocked, and this can be accomplished using the clinically approved drug AMD3100, a small molecule inhibitor of SDF-1/CXCR4 interactions.

  20. Inhibition of Egr1 expression underlies the anti-mitogenic effects of cAMP in vascular smooth muscle cells.

    PubMed

    Kimura, Tomomi E; Duggirala, Aparna; Hindmarch, Charles C T; Hewer, Richard C; Cui, Mei-Zhen; Newby, Andrew C; Bond, Mark

    2014-07-01

    Cyclic AMP inhibits vascular smooth muscle cell (VSMC) proliferation which is important in the aetiology of numerous vascular diseases. The anti-mitogenic properties of cAMP in VSMC are dependent on activation of protein kinase A (PKA) and exchange protein activated by cAMP (EPAC), but the mechanisms are unclear. Selective agonists of PKA and EPAC synergistically inhibited Egr1 expression, which was essential for VSMC proliferation. Forskolin, adenosine, A2B receptor agonist BAY60-6583 and Cicaprost also inhibited Egr1 expression in VSMC but not in endothelial cells. Inhibition of Egr1 by cAMP was independent of cAMP response element binding protein (CREB) activity but dependent on inhibition of serum response element (SRE) activity. SRF binding to the Egr1 promoter was not modulated by cAMP stimulation. However, Egr1 expression was dependent on the SRF co-factors Elk1 and 4 but independent of MAL. Inhibition of SRE-dependent Egr1 expression was due to synergistic inhibition of Rac1 activity by PKA and EPAC, resulting in rapid cytoskeleton remodelling and nuclear export of ERK1/2. This was associated with de-phosphorylation of the SRF co-factor Elk1. cAMP inhibits VSMC proliferation by rapidly inhibiting Egr1 expression. This occurs, at least in part, via inhibition of Rac1 activity leading to rapid actin-cytoskeleton remodelling, nuclear export of ERK1/2, impaired Elk1-phosphorylation and inhibition of SRE activity. This identifies one of the earliest mechanisms underlying the anti-mitogenic effects of cAMP in VSMC but not in endothelial cells, making it an attractive target for selective inhibition of VSMC proliferation. Copyright © 2014. Published by Elsevier Ltd.

  1. 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

  2. Continuous Low-dose-rate Irradiation of Iodine-125 Seeds Inhibiting Perineural Invasion in Pancreatic Cancer

    PubMed Central

    Lu, Zheng; Dong, Teng-Hui; Si, Pei-Ren; Shen, Wei; Bi, Yi-Liang; Min, Min; Chen, Xin; Liu, Yan

    2016-01-01

    Background: Perineural invasion (PNI) is a histopathological characteristic of pancreatic cancer (PanCa). The aim of this study was to observe the treatment effect of continuous low-dose-rate (CLDR) irradiation to PNI and assess the PNI-related pain relief caused by iodine-125 (125I) seed implantation. Methods: The in vitro PNI model established by co-culture with dorsal root ganglion (DRG) and cancer cells was interfered under 2 and 4 Gy of 125I seeds CLDR irradiation. The orthotopic models of PNI were established, and 125I seeds were implanted in tumor. The PNI-related molecules were analyzed. In 30 patients with panCa, the pain relief was assessed using a visual analog scale (VAS). Pain intensity was measured before and 1 week, 2 weeks, and 1, 3, and 6 months after 125I seed implantation. Results: The co-culture of DRG and PanCa cells could promote the growth of PanCa cells and DRG neurites. In co-culture groups, the increased number of DRG neurites and pancreatic cells in radiation group was significantly less. In orthotopic models, the PNI-positive rate in radiation and control group was 3/11 and 7/11; meanwhile, the degrees of PNI between radiation and control groups was significant difference (P < 0.05). At week 2, the mean VAS pain score in patients decreased by 50% and significantly improved than the score at baseline (P < 0.05). The pain scores were lower in all patients, and the pain-relieving effect was retained about 3 months. Conclusions: The CLDR irradiation could inhibit PNI of PanCa with the value of further study. The CLDR irradiation could do great favor in preventing local recurrence and alleviating pain. PMID:27748339

  3. Low-power laser irradiation inhibits Aβ25-35-induced cell apoptosis through Akt activation

    NASA Astrophysics Data System (ADS)

    Zhang, Zhigang; Tang, Yonghong

    2009-08-01

    Low-power laser irradiation (LPLI) can modulate various cellular processes such as proliferation, differentiation and apoptosis. Recently, LPLI has been applied to moderate Alzheimer's disease (AD), but the underlying mechanism remains unknown. The protective role of LPLI against the amyloid beta peptide (Aβ), a major constituent of AD plaques, has not been studied. PI3K/Akt pathway is extremely important in protecting cells from apoptosis caused by diverse stress stimuli. However, whether LPLI can inhibit Aβ-induced apoptosis through Akt activation is still unclear. In current study, using FRET (fluorescence resonance energy transfer) technique, we investigated the activity of Akt in response to LPLI treatment. B kinase activity reporter (BKAR), a recombinant FRET probe of Akt, was utilized to dynamically detect the activation of Akt after LPLI treatment. The results show that LPLI promoted the activation of Akt. Moreover, LPLI inhibits apoptosis induced by Aβ25-35 and the apoptosis inhibition can be abolished by wortmannin, a specific inhibitor of PI3K/Akt. Taken together, these results suggest that LPLI can inhibit Aβ25-35-induced cell apoptosis through Akt activation.

  4. Evidence for mRNA expression of vascular endothelial growth factor by X-ray irradiation in a lung squamous carcinoma cell line.

    PubMed

    Ando, S; Nojima, K; Majima, H; Ishihara, H; Suzuki, M; Furusawa, Y; Yamaguchi, H; Koike, S; Ando, K; Yamauchi, M; Kuriyama, T

    1998-10-23

    Vascular endothelial growth factor (VEGF) is a multipotent cytokine which plays an important role in various angiogenic conditions as well as in some tumor behaviors. Here we examined the induction of VEGF mRNA by X-ray irradiation in a lung squamous cell carcinoma cell line (RERF-LC-AI). Irradiating the cells with 15 Gy X-rays significantly increased the mRNA expression up to 2.5-fold of control at a post-irradiation time of 16-24 h. The induction of VEGF mRNA by X-ray irradiation was completely blocked by treating cells with either genistein (Src tyrosine kinase inhibitor) or H7 (protein kinase C inhibitor). This suggests that the mechanism of induction might be concerned with the pathway which triggers Src tyrosine kinase of the cell surface and the protein kinase C pathway.

  5. 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

  6. 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.

  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. PI3 kinase inhibition improves vascular malformations in mouse models of hereditary haemorrhagic telangiectasia.

    PubMed

    Ola, Roxana; Dubrac, Alexandre; Han, Jinah; Zhang, Feng; Fang, Jennifer S; Larrivée, Bruno; Lee, Monica; Urarte, Ana A; Kraehling, Jan R; Genet, Gael; Hirschi, Karen K; Sessa, William C; Canals, Francesc V; Graupera, Mariona; Yan, Minhong; Young, Lawrence H; Oh, Paul S; Eichmann, Anne

    2016-11-29

    Activin receptor-like kinase 1 (ALK1) is an endothelial serine-threonine kinase receptor for bone morphogenetic proteins (BMPs) 9 and 10. Inactivating mutations in the ALK1 gene cause hereditary haemorrhagic telangiectasia type 2 (HHT2), a disabling disease characterized by excessive angiogenesis with arteriovenous malformations (AVMs). Here we show that inducible, endothelial-specific homozygous Alk1 inactivation and BMP9/10 ligand blockade both lead to AVM formation in postnatal retinal vessels and internal organs including the gastrointestinal (GI) tract in mice. VEGF and PI3K/AKT signalling are increased on Alk1 deletion and BMP9/10 ligand blockade. Genetic deletion of the signal-transducing Vegfr2 receptor prevents excessive angiogenesis but does not fully revert AVM formation. In contrast, pharmacological PI3K inhibition efficiently prevents AVM formation and reverts established AVMs. Thus, Alk1 deletion leads to increased endothelial PI3K pathway activation that may be a novel target for the treatment of vascular lesions in HHT2.

  9. Neuronal nitric oxide synthase inhibition and regional sympathetic nerve discharge: implications for peripheral vascular control.

    PubMed

    Copp, Steven W; Hirai, Daniel M; Sims, Gabrielle E; Fels, Richard J; Musch, Timothy I; Poole, David C; Kenney, Michael J

    2013-05-01

    Neuronal nitric oxide (NO) synthase (nNOS) inhibition with systemically administered S-methyl-l-thiocitrulline (SMTC) elevates mean arterial pressure (MAP) and reduces rat hindlimb skeletal muscle and renal blood flow. We tested the hypothesis that those SMTC-induced cardiovascular effects resulted, in part, from increased sympathetic nerve discharge (SND). MAP, HR, and lumbar and renal SND (direct nerve recordings) were measured in 9 baroreceptor (sino-aortic)-denervated rats for 20min each following both saline and SMTC (0.56mg/kg i.v.). SMTC increased MAP (peak ΔMAP: 50±8mmHg, p<0.01) compared to saline. Lumbar and renal SND were not different between saline and SMTC conditions at any time (p>0.05). The ΔSND between saline and SMTC conditions for the lumbar and renal nerves were not different from zero (peak ΔSND, lumbar: 2.0±6.8%; renal: 9.7±9.0%, p>0.05 versus zero for both). These data support that SMTC-induced reductions in skeletal muscle and renal blood flow reported previously reflect peripheral nNOS-derived NO vascular control as opposed to increased sympathetic vasoconstriction. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Betaine inhibits vascularization via suppression of Akt in the retinas of streptozotocin-induced hyperglycemic rats

    PubMed Central

    KIM, YOUNG-GIUN; LIM, HYUNG-HO; LEE, SUH-HA; SHIN, MAL-SOON; KIM, CHANG-JU; YANG, HYEON JEONG

    2015-01-01

    Diabetic retinopathy is a severe microvascular complication amongst patients with diabetes, and is the primary cause of visual loss through neovascularization. Betaine is one of the components of Fructus Lycii. In the present study, the effects of betaine on the expression levels of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α in association with the Akt pathway were investigated in the retinas of streptozotocin (STZ)-induced diabetic rats using western blot and immunohistochemical analyses. The results of the present study revealed that the expression levels of VEGF, HIF-1α, and Akt were increased in the retinas of the STZ-induced diabetic rats. Betaine treatment attenuated this increase in VEGF and HIF-1α expression via suppression of diabetes-induced Akt activation in the retinas of the diabetic rats. The results suggested that betaine may potentially be used to delay the onset of complications associated with diabetic retinopathy via inhibition of retinal neovascularization in patients with diabetes. PMID:25891515

  11. Properdistatin inhibits angiogenesis and improves vascular function in human melanoma xenografts with low thrombospondin-1 expression

    PubMed Central

    Gaustad, Jon-Vidar; Simonsen, Trude G.; Andersen, Lise Mari K.; Rofstad, Einar K.

    2016-01-01

    In this study, the effect of properdistatin, a novel peptide derived from the thrombospondin 1 (TSP-1) domain of properdin, was investigated in three melanoma xenograft models with different TSP-1 expression. The tumors were grown in dorsal window chambers and were treated with 80 mg/kg/day properdistatin or vehicle. Morphological parameters of the tumor vasculature were assessed from high resolution transillumination images. Blood supply time (i.e., the time required for arterial blood to flow from a supplying artery to downstream microvessels) and plasma velocities were assessed from first-pass imaging movies recorded after a bolus of fluorescence-labeled dextran had been administered intravenously. Gene and protein expression of TSP-1 were assessed with quantitative PCR and immunohistochemistry, respectively. Properdistatin treatment inhibited angiogenesis in low TSP-1 expressing tumors but did not alter the vasculature in high TSP-1 expressing tumors. In low TSP-1 expressing tumors, properdistatin selectively removed small-diameter capillaries, but did not change the morphology of tumor arterioles or tumor venules. Properdistatin also reduced blood supply times and increased plasma velocities, implying that the treatment reduced the geometric resistance to blood flow and improved vascular function. PMID:27756886

  12. PI3 kinase inhibition improves vascular malformations in mouse models of hereditary haemorrhagic telangiectasia

    PubMed Central

    Ola, Roxana; Dubrac, Alexandre; Han, Jinah; Zhang, Feng; Fang, Jennifer S.; Larrivée, Bruno; Lee, Monica; Urarte, Ana A.; Kraehling, Jan R.; Genet, Gael; Hirschi, Karen K.; Sessa, William C.; Canals, Francesc V.; Graupera, Mariona; Yan, Minhong; Young, Lawrence H.; Oh, Paul S.; Eichmann, Anne

    2016-01-01

    Activin receptor-like kinase 1 (ALK1) is an endothelial serine–threonine kinase receptor for bone morphogenetic proteins (BMPs) 9 and 10. Inactivating mutations in the ALK1 gene cause hereditary haemorrhagic telangiectasia type 2 (HHT2), a disabling disease characterized by excessive angiogenesis with arteriovenous malformations (AVMs). Here we show that inducible, endothelial-specific homozygous Alk1 inactivation and BMP9/10 ligand blockade both lead to AVM formation in postnatal retinal vessels and internal organs including the gastrointestinal (GI) tract in mice. VEGF and PI3K/AKT signalling are increased on Alk1 deletion and BMP9/10 ligand blockade. Genetic deletion of the signal-transducing Vegfr2 receptor prevents excessive angiogenesis but does not fully revert AVM formation. In contrast, pharmacological PI3K inhibition efficiently prevents AVM formation and reverts established AVMs. Thus, Alk1 deletion leads to increased endothelial PI3K pathway activation that may be a novel target for the treatment of vascular lesions in HHT2. PMID:27897192

  13. 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.

  14. 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.

  15. Cleaved high-molecular-weight kininogen inhibits neointima formation following vascular injury.

    PubMed

    Daniel, Jan-Marcus; Reich, Fabian; Dutzmann, Jochen; Weisheit, Simona; Teske, Rebecca; Gündüz, Dursun; Bauersachs, Johann; Preissner, Klaus T; Sedding, Daniel G

    2015-08-31

    Cleaved high-molecular-weight kininogen (HKa) or its peptide domain 5 (D5) alone exert anti-adhesive properties in vitro related to impeding integrin-mediated cellular interactions. However, the anti-adhesive effects of HKa in vivo remain elusive. In this study, we investigated the effects of HKa on leukocyte recruitment and neointima formation following wire-induced injury of the femoral artery in C57BL/6 mice. Local application of HKa significantly reduced the accumulation of monocytes and also reduced neointimal lesion size 14 days after injury. Moreover, C57BL/6 mice transplanted with bone marrow from transgenic mice expressing enhanced green fluorescence protein (eGFP) showed a significantly reduced accumulation of eGFP+-cells at the arterial injury site and decreased neointimal lesion size after local application of HKa or the polypeptide D5 alone. A differentiation of accumulating eGFP+-cells into highly specific smooth muscle cells (SMC) was not detected in any group. In contrast, application of HKa significantly reduced the proliferation of locally derived neointimal cells. In vitro, HKa and D5 potently inhibited the adhesion of SMC to vitronectin, thus impairing their proliferation, migration, and survival rates. In conclusion, application of HKa or D5 decreases the inflammatory response to vascular injury and exerts direct effects on SMC by impeding the binding of integrins to extracellular matrix components. Therefore, HKa and D5 may hold promise as novel therapeutic substances to prevent neointima formation.

  16. Shikonin inhibits TNF-α-induced growth and invasion of rat aortic vascular smooth muscle cells.

    PubMed

    Zhang, Xuemin; Hu, Wenyu; Wu, Fang; Yuan, Xue; Hu, Jian

    2015-08-01

    Shikonin is a naphthoquinone compound extracted from the Chinese herb purple gromwell. Shikonin has broad antibacterial, anti-inflammatory, and antitumor activities. The tumor necrosis factor-α (TNF-α)-induced proliferation and invasion of vascular smooth muscle cells (VSMCs) is an important factor that contributes to atherosclerosis. The effects of shikonin on the proliferation and apoptosis of VSMCs have been reported; however, the function of shikonin on TNF-α-mediated growth and invasion of VSMCs during atherosclerosis remains unclear. In this study, we used Western blot, flow cytometry, real-time quantitative PCR, and enzyme-linked immunosorbent assay to investigate the effect of shikonin on the TNF-α-induced growth and invasion of VSMCs and to determine the underlying mechanism. Our results showed that shikonin inhibits the TNF-α-mediated growth and invasion. Further study revealed that shikonin regulates the activation of nuclear factor kappa B and phosphatidyl inositol 3-kinase signaling pathways; modulates the expression of cyclin D1, cyclin E, B-cell lymphoma 2, and Bax; activates caspase-3 and caspase-9; induces cell cycle arrest; and promotes the apoptosis of VSMCs. Together, our results indicate that shikonin may become a promising agent for the treatment of atherosclerosis and they also establish foundation for the development of anti-atherosclerosis drugs.

  17. [Inflammation inhibits vascular fibulin-5 expression: Involvement of transcription factor SOX9].

    PubMed

    Orriols, Mar; Varona, Saray; Aguiló, Silvia; Galán, María; Martínez González, José; Rodríguez, Cristina

    Fibulin-5 (FBLN5) is an elastogenic protein critically involved in extracellular matrix (ECM) remodelling, a key process in abdominal aortic aneurysm (AAA). However, the possible contribution of FBLN5 to AAA development has not been addressed. Expression levels were determined by real-time PCR and Western blot in human abdominal aorta from patients with AAA or healthy donors, as well as in human aortic vascular smooth muscle cells (VSMC). Lentiviral transduction, transient transfections, and chromatin immunoprecipitation (ChIP) assays were also performed. The expression of FBLN5 in human AAA was significantly lower than in healthy donors. FBLN5 mRNA and protein levels and their secretion to the extracellular environment were down-regulated in VSMC exposed to inflammatory stimuli. Interestingly, FBLN5 transcriptional activity was inhibited by TNFα and lipopolysaccharide (LPS), and depends on a SOX response element. In fact, SOX9 expression was reduced in VMSC induced by inflammatory mediators and in human AAA, and correlated with that of FBLN5. Furthermore, SOX9 over-expression limited the reduction of FBLN5 expression induced by cytokines in VSMC. Finally, it was observed that SOX9 interacts with FBLN5 promoter, and that this binding was reduced upon TNFα exposure. FBLN5 downregulation in human AAA could contribute to extracellular matrix remodelling induced by the inflammatory component of the disease. Copyright © 2016 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Peach (Prunus persica) extract inhibits angiotensin II-induced signal transduction in vascular smooth muscle cells.

    PubMed

    Kono, Ryohei; Okuno, Yoshiharu; Nakamura, Misa; Inada, Ken-ichi; Tokuda, Akihiko; Yamashita, Miki; Hidaka, Ryu; Utsunomiya, Hirotoshi

    2013-08-15

    Angiotensin II (Ang II) is a vasoactive hormone that has been implicated in cardiovascular diseases. Here, the effect of peach, Prunus persica L. Batsch, pulp extract on Ang II-induced intracellular Ca(2+) mobilization, reactive oxygen species (ROS) production and signal transduction events in cultured vascular smooth muscle cells (VSMCs) was investigated. Pretreatment of peach ethyl acetate extract inhibited Ang II-induced intracellular Ca(2+) elevation in VSMCs. Furthermore, Ang II-induced ROS generation, essential for signal transduction events, was diminished by the peach ethyl acetate extract. The peach ethyl acetate extract also attenuated the Ang II-induced phosphorylation of epidermal growth factor receptor and myosin phosphatase target subunit 1, both of which are associated with atherosclerosis and hypertension. These results suggest that peach ethyl acetate extract may have clinical potential for preventing cardiovascular diseases by interfering with Ang II-induced intracellular Ca(2+) elevation, the generation of ROS, and then blocking signal transduction events. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. 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.

  20. Inhibition of kinin B1 receptors attenuates pulmonary hypertension and vascular remodeling.

    PubMed

    Murugesan, Priya; Hildebrandt, Tobias; Bernlöhr, Christian; Lee, Dongwon; Khang, Gilson; Doods, Henri; Wu, Dongmei

    2015-10-01

    This study examined whether the kinin B1 receptor is involved in the pathogenesis of pulmonary hypertension, and whether its inhibition could reduce inflammation, pulmonary hypertension, vascular remodeling, and right heart dysfunction. Male Wistar rats underwent left pneumonectomy. Seven days later, the rats were injected subcutaneously with monocrotaline (60 mg/kg). The rats were then randomly assigned to receive treatment with vehicle or with BI113823 (a selective B1 receptor antagonist, 30 mg/kg, twice per day) via oral gavage from the day of monocrotaline injection to day 28. By day 28, BI113823-treated rats had significantly lower mean pulmonary artery pressure, less right ventricular hypertrophy, and pulmonary arterial neointimal formation than that of the vehicle-treated rats. Real-time polymerase chain reaction revealed that there was a significant increase in mRNA expression of B1 receptors in the lungs of monocrotaline-challenged pneumonectomized rats. Treatment with BI113823 significantly reduced macrophage recruitment, as measured via bronchoalveolar lavage. It also markedly reduced CD-68 positive macrophages and proliferating cell nuclear antigen positive cells in the perivascular areas, reduced expression of inducible nitric oxide synthase, matrix metalloproteinase 2 and 9, and B1 receptors compared with measurements in vehicle-treated rats. These findings demonstrate that kinin B1 receptors represent a novel therapeutic target for pulmonary arterial hypertension.

  1. 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

  2. Hesperidin methyl chalcone inhibits oxidative stress and inflammation in a mouse model of ultraviolet B irradiation-induced skin damage.

    PubMed

    Martinez, Renata M; Pinho-Ribeiro, Felipe A; Steffen, Vinicius S; Caviglione, Carla V; Vignoli, Josiane A; Baracat, Marcela M; Georgetti, Sandra R; Verri, Waldiceu A; Casagrande, Rubia

    2015-07-01

    Hesperidin methyl chalcone (HMC) is a safe flavonoid used to treat chronic venous diseases, but its effects and mechanisms on UVB irradiation-induced inflammation and oxidative stress have never been described in vivo. Thus, the purpose of this study was to evaluate the effects of systemic administration of HMC in skin oxidative stress and inflammation induced by UVB irradiation. To induce skin damage, hairless mice were exposed to an acute UVB irradiation dose of 4.14 J/cm(2), and the dorsal skin samples were collected to evaluate oxidative stress and inflammatory response. The intraperitoneal treatment with HMC at the dose of 300 mg/kg inhibited UVB irradiation-induced skin edema, neutrophil recruitment, and matrix metalloproteinase-9 activity. HMC also protected the skin from UVB irradiation-induced oxidative stress by maintaining ferric reducing antioxidant power (FRAP), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS) scavenging ability and antioxidant levels (reduced glutathione and catalase). Corroborating, HMC inhibited UVB irradiation-induced superoxide anion generation and gp91phox (NADPH oxidase subunit) mRNA expression. Furthermore, the antioxidant effect of HMC resulted in lower production of inflammatory mediators, including lipid hydroperoxides and a wide range of cytokines. Taken together, these results unveil a novel applicability of HMC in the treatment of UVB irradiation-induced skin inflammation and oxidative stress. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. 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

  4. Low-power laser irradiation inhibits arecoline-induced fibrosis: an in vitro study

    PubMed Central

    Yeh, Mei-Chun; Chen, Ker-Kong; Chiang, Min-Hsuan; Chen, Chia-Hsin; Chen, Ping-Ho; Lee, Huey-Er; Wang, Yan-Hsiung

    2017-01-01

    Oral submucous fibrosis (OSF) is a potentially malignant disorder that is characterized by a progressive fibrosis in the oral submucosa. Arecoline, an alkaloid compound of the areca nut, is reported to be a major aetiological factor in the development of OSF. Low-power laser irradiation (LPLI) has been reported to be beneficial in fibrosis prevention in different damaged organs. The aim of this study was to investigate the potential therapeutic effects of LPLI on arecoline-induced fibrosis. Arecoline-stimulated human gingival fibroblasts (HGFs) were treated with or without LPLI. The expression levels of the fibrotic marker genes alpha-smooth muscle actin (α-SMA) and connective tissue growth factor (CTGF/CCN2) were analysed by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) and western blots. In addition, the transcriptional activity of CCN2 was further determined by a reporter assay. The results indicated that arecoline increased the messenger RNA and protein expression of CCN2 and α-SMA in HGF. Interestingly, both LPLI and forskolin, an adenylyl cyclase activator, reduced the expression of arecoline-mediated fibrotic marker genes and inhibited the transcriptional activity of CCN2. Moreover, pretreatment with SQ22536, an adenylyl cyclase inhibitor, blocked LPLI's inhibition of the expression of arecoline-mediated fibrotic marker genes. Our data suggest that LPLI may inhibit the expression of arecoline-mediated fibrotic marker genes via the cAMP signalling pathway. PMID:28233766

  5. Dopamine induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages in rat C6 glioma

    SciTech Connect

    Qin, Tian; Wang, Chenlong; Chen, Xuewei; Duan, Chenfan; Zhang, Xiaoyan; Zhang, Jing; Chai, Hongyan; Tang, Tian; Chen, Honglei; Yue, Jiang; Li, Ying; Yang, Jing

    2015-07-15

    Dopamine (DA), a monoamine catecholamine neurotransmitter with antiangiogenic activity, stabilizes tumor vessels in colon, prostate and ovarian cancers, thus increases chemotherapeutic efficacy. Here, in the rat C6 glioma models, we investigated the vascular normalization effects of DA and its mechanisms of action. DA (25, 50 mg/kg) inhibited tumor growth, while a precursor of DA (levodopa) prolonged the survival time of rats bearing orthotopic C6 glioma. DA improved tumor perfusion, with significant effects from day 3, and a higher level at days 5 to 7. In addition, DA decreased microvessel density and hypoxia-inducible factor-1α expression in tumor tissues, while increasing the coverage of pericyte. Conversely, an antagonist of dopamine receptor 2 (DR2) (eticlopride) but not DR1 (butaclamol) abrogated DA-induced tumor regression and vascular normalization. Furthermore, DA improved the delivery and efficacy of temozolomide therapy. Importantly, DA increased representative M1 markers (iNOS, CXCL9, etc.), while decreasing M2 markers (CD206, arginase-1, etc.). Depletion of macrophages by clodronate or zoledronic acid attenuated the effects of DA. Notably, DA treatment induced M2-to-M1 polarization in RAW264.7 cells and mouse peritoneal macrophages, and enhanced the migration of pericyte-like cells (10T1/2), which was reversed by eticlopride or DR2-siRNA. Such changes were accompanied by the downregulation of VEGF/VEGFR2 signaling. In summary, DA induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages. Thus, targeting the tumor microvasculature by DA represents a promising strategy for human glioma therapy. - Highlights: • Dopamine induces tumor growth inhibition and vascular normalization in rat C6 glioma. • Dopamine switches macrophage phenotype from M2 to M1. • Dopamine-induced vascular normalization is mediated by macrophage polarization. • Dopamine is a promising agent targeting the microvasculature in tumor

  6. Desalted Salicornia europaea extract attenuated vascular neointima formation by inhibiting the MAPK pathway-mediated migration and proliferation in vascular smooth muscle cells.

    PubMed

    Won, Kyung Jong; Lee, Kang Pa; Baek, Suji; Cui, Long; Kweon, Mee-Hyang; Jung, Seung Hyo; Ryu, Yun-Kyoung; Hong, Jung Min; Cho, Eun-Ah; Shin, Hwa-Sup; Kim, Bokyung

    2017-10-01

    Salicornia europaea L. (SE) has been used as folk medicine for the treatment of various diseases such as obesity, diabetes, and cancer. However, its effects on atherosclerotic events in vascular smooth muscle cells (VSMCs) remain unknown. The present study explored the effects of the ethyl acetate fraction of desalted SE hot water extract (SEWEAF) on atherosclerotic responses (especially migration and proliferation) in VSMCs and vascular neointima formation. Treatment with the SEWEAF significantly suppressed the platelet-derived growth factor (PDGF)-BB-induced VSMC migration and proliferation as well the phosphorylation of mitogen-activated protein kinases (MAPKs) such as the p38 MAPK and extracellular signal-regulated kinase (ERK) 1/2. Moreover, oral administration of the SEWEAF resulted in the attenuation of neointima formation in balloon-injured rat carotid arteries. Additionally, HPLC analysis showed that the major components in the two subfractions of the SEWEAF were five phenolic acids and four flavonols. In the SEWEAF components, for which atherosclerosis-linked responses in VSMCs have not been known, p-coumaric acid, quercetin-3-β-d-glucoside, and isorhamnetin-3-β-d-glucoside inhibited both PDGF-BB-induced migration and proliferation and isorhamnetin attenuated only PDGF-BB-stimulated VSMC proliferation. These results suggest that the SEWEAF may suppress PDGF-BB-induced VSMC migration by downregulating the phosphorylation of p38 MAPK and ERK1/2, thus leading to the reduction of neointimal hyperplasia during vascular remodeling. Therefore, the desalted SE extract, SEWEAF may be a potential ingredient for dietary supplements or nutraceuticals to ameliorate and/or prevent vascular remodeling-related disorders. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  7. Plant Photosynthesis-Irradiance Curve Responses to Pollution Show Non-Competitive Inhibited Michaelis Kinetics.

    PubMed

    Lin, Maozi; Wang, Zhiwei; He, Lingchao; Xu, Kang; Cheng, Dongliang; Wang, Genxuan

    2015-01-01

    Photosynthesis-irradiance (PI) curves are extensively used in field and laboratory research to evaluate the photon-use efficiency of plants. However, most existing models for PI curves focus on the relationship between the photosynthetic rate (Pn) and photosynthetically active radiation (PAR), and do not take account of the influence of environmental factors on the curve. In the present study, we used a new non-competitive inhibited Michaelis-Menten model (NIMM) to predict the co-variation of Pn, PAR, and the relative pollution index (I). We then evaluated the model with published data and our own experimental data. The results indicate that the Pn of plants decreased with increasing I in the environment and, as predicted, were all fitted well by the NIMM model. Therefore, our model provides a robust basis to evaluate and understand the influence of environmental pollution on plant photosynthesis.

  8. Plant Photosynthesis-Irradiance Curve Responses to Pollution Show Non-Competitive Inhibited Michaelis Kinetics

    PubMed Central

    Lin, Maozi; Wang, Zhiwei; He, Lingchao; Xu, Kang; Cheng, Dongliang; Wang, Genxuan

    2015-01-01

    Photosynthesis-irradiance (PI) curves are extensively used in field and laboratory research to evaluate the photon-use efficiency of plants. However, most existing models for PI curves focus on the relationship between the photosynthetic rate (Pn) and photosynthetically active radiation (PAR), and do not take account of the influence of environmental factors on the curve. In the present study, we used a new non-competitive inhibited Michaelis-Menten model (NIMM) to predict the co-variation of Pn, PAR, and the relative pollution index (I). We then evaluated the model with published data and our own experimental data. The results indicate that the Pn of plants decreased with increasing I in the environment and, as predicted, were all fitted well by the NIMM model. Therefore, our model provides a robust basis to evaluate and understand the influence of environmental pollution on plant photosynthesis. PMID:26561863

  9. Irradiation of light emitting diode at 850nm inhibits T cell-induced cytokine expression.

    PubMed

    Cheong, Kyung Ah; Kim, Chang-Hyun; Choi, Yunseok; Park, Chan Do; Lee, Ai-Young

    2012-01-01

    An anti-inflammatory effect of light obtained from light-emitting diodes (LEDs) has been discovered, however, limited ranges of wavelengths have been used and the action mechanism has been rarely demonstrated. We sought to analyze the immunomodulatory effect of LED on Jurkat T cells and human T cells. Jurkat T cells with/without stimulation were irradiated once or five times using seven ranges of LED wavelengths, from 415nm to 940nm. Cytotoxic effects were examined by an MTT assay. Changes in T cell-induced cytokines, including IL-2, IL-4, IL-10, IL-12 and IFN-gamma, and their upstream signaling molecules, ZAP-70 and PKCθ, were examined by real-time PCR, ELISA, and Western blot analysis. The effect of the LED wavelength, whose effect was identified on Jurkat T cells, was also examined in human CD3+ T cells with/without stimulation and in Dermatophagoides farinae-induced atopic dermatitis (AD) NC/Nga mice. Lower doses of LED irradiation at 850nm inhibited T cell-derived cytokines without inducing cell death in both Jurkat T cells and human T cells. Repeated exposure resulted in a greater increase of inhibitory effects than that observed with a single exposure, and these effects were identified in the NC/Nga AD model. Although more remains to be clarified, these results may support the clinical application of LED for immune regulation. Copyright © 2011 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  10. Irradiation inhibits the maturation and mineralization of osteoblasts via the activation of Nrf2/HO-1 pathway.

    PubMed

    Kook, Sung-Ho; Kim, Kyoung-A; Ji, Hyeok; Lee, Daewoo; Lee, Jeong-Chae

    2015-12-01

    Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) regulates the induction of antioxidant gene expression and protects cells against oxidative injury. However, there are controversial findings regarding the roles of Nrf2 on bone metabolism under oxidative stress. The role of Nrf2 on the differentiation of radiation-exposed osteoblasts is also unclear. We investigated whether Nrf2 negatively or positively affects osteoblast differentiation in response to irradiation. Irradiation inhibited osteoblast differentiation of MC3T3-E1 cells in a dose-dependent manner. This inhibition was evidenced by the irradiation-mediated decreases in bone-like nodule formation, alkaline phosphatase (ALP) activity, calcium accumulation, and expression of osteoblast markers, such as ALP, osteocalcin, osteopontin, bone sialoprotein, osterix, and Runx2. These reductions were accompanied by increased induction of Nrf2 and heme oxygenase-1 (HO-1), accumulation of cellular oxidants, and depletion of antioxidant defense enzymes. siRNA-mediated silencing of Nrf2 markedly reversed the negative effect of irradiation on osteoblast differentiation of the cells, leading to a decrease in HO-1 and an increase in Runx2 levels. Irradiation-mediated decreases in the levels of Runx2 and osteocalcin mRNA, but not of Nrf2 protein, were also significantly inhibited by HO-1 inhibitor, zinc protoporphyrin IX. Furthermore, N-acetyl cysteine restored all of the changes induced by irradiation to near-normal levels in the cells. These results demonstrate that irradiation inhibits osteoblast differentiation and mineralization of MC3T3-E1 cells through the oxidative stress-mediated activation of Nrf2/HO-1 pathway.

  11. Kaempferol inhibits vascular smooth muscle cell migration by modulating BMP-mediated miR-21 expression.

    PubMed

    Kim, Kwangho; Kim, Sunghwan; Moh, Sang Hyun; Kang, Hara

    2015-09-01

    Bioflavonoids are known to induce cardioprotective effects by inhibiting vascular smooth muscle cell (VSMC) proliferation and migration. Kaempferol has been shown to inhibit VSMC proliferation. However, little is known about the effect of kaempferol on VSMC migration and the underlying molecular mechanisms. Our studies provide the first evidence that kaempferol inhibits VSMC migration by modulating the BMP4 signaling pathway and microRNA expression levels. Kaempferol activates the BMP signaling pathway, induces miR-21 expression and downregulates DOCK4, 5, and 7, leading to inhibition of cell migration. Moreover, kaempferol antagonizes the PDGF-mediated pro-migratory effect. Therefore, our study uncovers a novel regulatory mechanism of VSMC migration by kaempferol and suggests that miRNA modulation by kaempferol is a potential therapy for cardiovascular diseases.

  12. [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.

  13. Tocopherols and 6-hydroxy-chroman-2-carbonitrile derivatives inhibit vascular smooth muscle cell proliferation by a nonantioxidant mechanism.

    PubMed

    Boscoboinik, D; Ozer, N K; Moser, U; Azzi, A

    1995-04-01

    The effects of two groups of similar compounds, a series of tocopherols and one of 6-hydroxy-chroman-2-carbonitrile, have been studied in vascular smooth muscle cells. A poor correlation has been found between antiproliferative and antioxidant properties of these molecules. D-alpha-Tocopherol inhibits cell proliferation, while D-alpha-tocopherylquinone has been found neither to inhibit nor to activate. D-beta-Tocopherol, a poor inhibitor of smooth muscle cell proliferation, has been shown to be capable of preventing and reversing the inhibition by D-alpha-tocopherol. It is concluded that the tocopherols and carbonitrile derivatives tested here appear to inhibit smooth muscle cell proliferation by a nonantioxidant mechanism. The competition between D-alpha-tocopherol and D-beta-tocopherol suggests the existence of a common binding site for the two molecules.

  14. (-)-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.

  15. Hepatic Overexpression of Hemopexin Inhibits Inflammation and Vascular Stasis in Murine Models of Sickle Cell Disease.

    PubMed

    Vercellotti, Gregory M; Zhang, Ping; Nguyen, Julia; Abdulla, Fuad; Chen, Chunsheng; Nguyen, Phong; Nowotny, Carlos; Steer, Clifford J; Smith, Ann; Belcher, John D

    2016-07-19

    Sickle cell disease (SCD) patients have low serum hemopexin (Hpx) levels due to chronic hemolysis. We hypothesize that in SCD mice, hepatic overexpression of hemopexin will scavenge the proximal mediator of vascular activation, heme, and will inhibit inflammation and microvascular stasis. To examine the protective role of Hpx in SCD, we transplanted bone marrow from NY1DD SCD mice into Hpx(-/-) or Hpx(+/+) C57BL/6 mice. Dorsal skin fold chambers were implanted in week 13 post-transplant and microvascular stasis (% non-flowing venules) evaluated in response to heme infusion. Hpx(-/-) sickle mice had significantly greater microvascular stasis in response to heme infusion than Hpx(+/+) sickle mice (p<0.05), demonstrating the protective effect of Hpx in SCD. We utilized Sleeping Beauty (SB) transposon-mediated gene transfer to overexpress wild-type rat Hpx (wt-Hpx) in NY1DD and Townes-SS SCD mice. Control SCD mice were treated with lactated Ringer's solution (LRS) or a luciferase (Luc) plasmid. Plasma and hepatic Hpx were significantly increased compared to LRS and Luc controls. Microvascular stasis in response to heme infusion in NY1DD and Townes-SS mice overexpressing wt-Hpx had significantly less stasis than controls (p<0.05). Wt-Hpx overexpression markedly increased hepatic nuclear Nrf2 expression, HO-1 activity and protein, the heme-Hpx binding protein and scavenger receptor, CD91/LRP1 and decreased NF-κB activation. Two missense (ms)-Hpx SB-constructs that bound neither heme nor the Hpx receptor, CD91/LRP1, did not prevent heme-induced stasis. In conclusion, increasing Hpx levels in transgenic sickle mice via gene transfer activates the Nrf2/HO-1 anti-oxidant axis and ameliorates inflammation and vaso-occlusion.

  16. Hepatic Overexpression of Hemopexin Inhibits Inflammation and Vascular Stasis in Murine Models of Sickle Cell Disease

    PubMed Central

    Vercellotti, Gregory M; Zhang, Ping; Nguyen, Julia; Abdulla, Fuad; Chen, Chunsheng; Nguyen, Phong; Nowotny, Carlos; Steer, Clifford J; Smith, Ann; Belcher, John D

    2016-01-01

    Sickle cell disease (SCD) patients have low serum hemopexin (Hpx) levels due to chronic hemolysis. We hypothesized that in SCD mice, hepatic overexpression of hemopexin would scavenge the proximal mediator of vascular activation, heme, and inhibit inflammation and microvascular stasis. To examine the protective role of Hpx in SCD, we transplanted bone marrow from NY1DD SCD mice into Hpx-/- or Hpx+/+ C57BL/6 mice. Dorsal skin fold chambers were implanted 13 wks post-transplant, and microvascular stasis (% nonflowing venules) was evaluated in response to heme infusion. Hpx-/- sickle mice had significantly greater microvascular stasis in response to heme infusion than Hpx+/+ sickle mice (p < 0.05), demonstrating the protective effect of Hpx in SCD. We utilized Sleeping Beauty (SB) transposon-mediated gene transfer to overexpress wild-type rat Hpx (wt-Hpx) in NY1DD and Townes-SS SCD mice. Control SCD mice were treated with lactated Ringer’s solution (LRS) or a luciferase (Luc) plasmid. Plasma and hepatic Hpx were significantly increased compared with LRS and Luc controls. Microvascular stasis in response to heme infusion in NY1DD and Townes-SS mice overexpressing wt-Hpx had significantly less stasis than controls (p < 0.05). Wt-Hpx overexpression markedly increased hepatic nuclear Nrf2 expression, HO-1 activity and protein, and the heme-Hpx binding protein and scavenger receptor CD91/LRP1, and decreased NF-κB activation. Two missense (ms)-Hpx SB constructs that bound neither heme nor the Hpx receptor CD91/LRP1 did not prevent heme-induced stasis. In conclusion, increasing Hpx levels in transgenic sickle mice via gene transfer activates the Nrf2/HO-1 antioxidant axis and ameliorates inflammation and vasoocclusion. PMID:27451971

  17. cGMP phosphodiesterase inhibition improves the vascular and metabolic actions of insulin in skeletal muscle.

    PubMed

    Genders, A J; Bradley, E A; Rattigan, S; Richards, S M

    2011-08-01

    There is considerable support for the concept that insulin-mediated increases in microvascular blood flow to muscle impact significantly on muscle glucose uptake. Since the microvascular blood flow increases with insulin have been shown to be nitric oxide-dependent inhibition of cGMP-degrading phosphodiesterases (cGMP PDEs) is predicted to enhance insulin-mediated increases in microvascular perfusion and muscle glucose uptake. Therefore, we studied the effects of the pan-cGMP PDE inhibitor zaprinast on the metabolic and vascular actions of insulin in muscle. Hyperinsulinemic euglycemic clamps (3 mU·min(-1)·kg(-1)) were performed in anesthetized rats and changes in microvascular blood flow assessed from rates of 1-methylxanthine metabolism across the muscle bed by capillary xanthine oxidase in response to insulin and zaprinast. We also characterized cGMP PDE isoform expression in muscle by real-time PCR and immunostaining of frozen muscle sections. Zaprinast enhanced insulin-mediated microvascular perfusion by 29% and muscle glucose uptake by 89%, while whole body glucose infusion rate during insulin infusion was increased by 33% at 2 h. PDE2, -9, and -10 were the major isoforms expressed at the mRNA level in muscle, while PDE1B, -9A, -10A, and -11A proteins were expressed in blood vessels. Acute administration of the cGMP PDE inhibitor zaprinast enhances muscle microvascular blood flow and glucose uptake response to insulin. The expression of a number of cGMP PDE isoforms in skeletal muscle suggests that targeting specific cGMP PDE isoforms may provide a promising avenue for development of a novel class of therapeutics for enhancing muscle insulin sensitivity.

  18. 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.

  19. β-Secretase (BACE1) inhibition causes retinal pathology by vascular dysregulation and accumulation of age pigment.

    PubMed

    Cai, Jun; Qi, Xiaoping; Kociok, Norbert; Skosyrski, Sergej; Emilio, Alonso; Ruan, Qing; Han, Song; Liu, Li; Chen, Zhijuan; Bowes Rickman, Catherine; Golde, Todd; Grant, Maria B; Saftig, Paul; Serneels, Lutgarde; de Strooper, Bart; Joussen, Antonia M; Boulton, Michael E

    2012-09-01

    β-Secretase (BACE1) is a major drug target for combating Alzheimer's disease (AD). Here we show that BACE1(-/-) mice develop significant retinal pathology including retinal thinning, apoptosis, reduced retinal vascular density and an increase in the age pigment, lipofuscin. BACE1 expression is highest in the neural retina while BACE2 was greatest in the retinal pigment epithelium (RPE)/choroid. Pigment epithelial-derived factor, a known regulator of γ-secretase, inhibits vascular endothelial growth factor (VEGF)-induced in vitro and in vivo angiogenesis and this is abolished by BACE1 inhibition. Moreover, intravitreal administration of BACE1 inhibitor or BACE1 small interfering RNA (siRNA) increases choroidal neovascularization in mice. BACE1 induces ectodomain shedding of vascular endothelial growth factor receptor 1 (VEGFR1) which is a prerequisite for γ-secretase release of a 100 kDa intracellular domain. The increase in lipofuscin following BACE1 inhibition and RNAI knockdown is associated with lysosomal perturbations. Taken together, our data show that BACE1 plays a critical role in retinal homeostasis and that the use of BACE inhibitors for AD should be viewed with extreme caution as they could lead to retinal pathology and exacerbate conditions such as age-related macular degeneration.

  20. 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

  1. Fruit-juice concentrate of Asian plum inhibits growth signals of vascular smooth muscle cells induced by angiotensin II.

    PubMed

    Utsunomiya, Hirotoshi; Takekoshi, Susumu; Gato, Nobuki; Utatsu, Hisao; Motley, Evangeline D; Eguchi, Kunie; Fitzgerald, Trinita G; Mifune, Mizuo; Frank, Gerald D; Eguchi, Satoru

    2002-12-27

    Bainiku-ekisu, the fruit-juice concentrate of the Oriental plum (Prunus mume) has recently been shown to improve human blood fluidity. We have shown that angiotensin II (AngII) stimulates growth of vascular smooth muscle cells (VSMCs) through epidermal growth factor (EGF) receptor transactivation that involves reactive oxygen species (ROS) production. To better understanding the possible cardiovascular protective effect of Bainiku-ekisu, we have studied whether Bainiku-ekisu inhibits AngII-induced growth promoting signals in VSMCs. Bainiku-ekisu markedly inhibited AngII-induced EGF receptor transactivation. H(2)O(2)-induced EGF receptor transactivation was also inhibited by Bainiku-ekisu. Thus, Bainiku-ekisu markedly inhibited AngII-induced extracellular signal-regulated kinase (ERK) activation. However, EGF-induced ERK activation was not affected by Bainiku-ekisu. AngII stimulated leucine uptake in VSMCs that was significantly inhibited by Bainiku-ekisu. Also, Bainiku-ekisu possesses a potent antioxidant activity. Since the activation of EGF receptor, ERK and the production of ROS play central roles in mediating AngII-induced vascular remodeling, these data suggest that Bainiku-ekisu could exert a powerful cardiovascular protective effect with regard to cardiovascular diseases.

  2. Effects of low intensity laser acupoint irradiation on inhibiting islet beta-cell apoptosis in rats with type 2 diabetes

    NASA Astrophysics Data System (ADS)

    Xiong, Guoxin; Xiong, Leilei; Li, Xinzhong

    2016-09-01

    To investigate the effects of low intensity semiconductor laser acupoint irradiation on inhibiting islet beta-cell apoptosis in rats with type 2 diabetes, a method using a high-fat diet and low-dose intraperitoneal injections of streptozotocin established a type 2 diabetes mellitus rat model. Model rats were randomly divided into a laser acupoint irradiation group, rosiglitazone control group, and placebo group; each group had 10 rats. In addition, 10 normal male rats were selected for the normal control group. The Housanli, Neiting and Yishu acupoints of the rats in the laser acupoint irradiation group were irradiated with a 10 mW semiconductor laser; each point was irradiated for 15 min, once every 2 d over 28 d, for a total of 14 episodes of irradiation. The rosiglitazone group rats were given rosiglitazone (0.2 mg kg-1) intragastrically; the placebo group rats were given 0.9% brine (0.2 mg kg-1) intragastrically, once daily, for four consecutive weeks. The change of fasting blood glucose was determined before and after each treatment. The islet beta-cell apoptosis was determined. The islet beta-cell apoptosis rates of the laser acupoint irradiation group and the rosiglitazone group were significantly lower than the rate of the placebo group. Even though the rate was lower in the laser acupoint irradiation group than in the rosiglitazone group, there was no significant difference between them. It is shown that acupoint irradiation with a semiconductor laser can effectively inhibit islet beta-cell apoptosis in rats with type 2 diabetes.

  3. Chemoresistance to 5-FU inhibited by 635 nm LED irradiation in CD133+ KB cell line.

    PubMed

    Kim, Donghwi; Park, Mineon; Jang, Hyunwoong; Hyun, Hoon; Lim, Wonbong

    2017-09-27

    Consistent with cancer stem cell theory, a small fraction of cancer cells, described as cancer stem cells (CSCs), may promote tumor recurrence and anti-cancer drug resistance. Therefore, much effort has been devoted to the development of CSC targeted therapy to vanquish drug resistance. In this study, we have investigated the effect of multiple light-emitting diode (LED) irradiation treatments with conventional anti-cancer drugs on CSC-like oral cancer cells that acquired stemness by ectopic over expression of CD133. To evaluate combined LED irradiation anti-cancer drug effects, we investigated the chemosensitizing effect of 635 nm irradiation on 5-fluorouracil (5FU)-treated KB(CD133+) and KB(Vec) cells, interrogating the underlying molecular mechanisms associated with stemness and apoptosis that are responsible for chemopreventive activity. In addition, combination therapy with LED irradiation and 5-FU treatment was carried out in KB(CD133+) and KB(Vec) cell-inoculated mouse models. LED irradiation of 635 nm inhibited CSC-like properties consistent with a decrease in OCT4 and NANOG protein expression, reducing colony-forming ability. In addition, LED irradiation enhanced 5-FU-induced cytotoxicity and improved 5-FU chemosensitivity in KB(CD133+) via enhancement of apoptosis. These findings were validated in vivo, wherein LED irradiation combined with 5-FU treatment inhibited tumor growth in KB(CD133+)-inoculated mice. Collectively, our results provide novel evidence for 635 nm irradiation-induced 5-FU chemosensitization of CSC in oral cancer. In addition, this research highlights that 635 nm LED irradiation may serve as an adjunct treatment to conventional chemotherapeutic drugs in patients with oral cancer.

  4. Cystathionine γ-lyase protects vascular endothelium: a role for inhibition of histone deacetylase 6.

    PubMed

    Leucker, Thorsten M; Nomura, Yohei; Kim, Jae Hyung; Bhatta, Anil; Wang, Victor; Wecker, Andrea; Jandu, Sandeep; Santhanam, Lakshmi; Berkowitz, Dan; Romer, Lewis; Pandey, Deepesh

    2017-04-01

    Endothelial cystathionine γ-lyase (CSEγ) contributes to cardiovascular homeostasis, mainly through production of H2S. However, the molecular mechanisms that control CSEγ gene expression in the endothelium during cardiovascular diseases are unclear. The aim of the current study is to determine the role of specific histone deacetylases (HDACs) in the regulation of endothelial CSEγ. Reduced CSEγ mRNA expression and protein abundance were observed in human aortic endothelial cells (HAEC) exposed to oxidized LDL (OxLDL) and in aortas from atherogenic apolipoprotein E knockout (ApoE(-/-)) mice fed a high-fat diet compared with controls. Intact murine aortic rings exposed to OxLDL (50 μg/ml) for 24 h exhibited impaired endothelium-dependent vasorelaxation that was blocked by CSEγ overexpression or the H2S donor NaHS. CSEγ expression was upregulated by pan-HDAC inhibitors and by class II-specific HDAC inhibitors, but not by other class-specific inhibitors. The HDAC6 selective inhibitor tubacin and HDAC6-specific siRNA increased CSEγ expression and blocked OxLDL-mediated reductions in endothelial CSEγ expression and CSEγ promoter activity, indicating that HDAC6 is a specific regulator of CSEγ expression. Consistent with this finding, HDAC6 mRNA, protein expression, and activity were upregulated in OxLDL-exposed HAEC, but not in human aortic smooth muscle cells. HDAC6 protein levels in aortas from high-fat diet-fed ApoE(-/-) mice were comparable to those in controls, whereas HDAC6 activity was robustly upregulated. Together, our findings indicate that HDAC6 is upregulated by atherogenic stimuli via posttranslational modifications and is a critical regulator of CSEγ expression in vascular endothelium. Inhibition of HDAC6 activity may improve endothelial function and prevent or reverse the development of atherosclerosis.NEW & NOTEWORTHY Oxidative injury to endothelial cells by oxidized LDL reduced cystathionine γ-lyase (CSEγ) expression and H2S production

  5. Orientin inhibits high glucose-induced vascular inflammation in vitro and in vivo.

    PubMed

    Ku, Sae-Kwang; Kwak, Soyoung; Bae, Jong-Sup

    2014-12-01

    Vascular inflammation plays a key role in the initiation and progression of atherosclerosis, a major complication of diabetes mellitus. Orientin, a C-glycosyl flavonoid, is known to have anxiolytic and antioxidative activity. In this study, we assessed whether orientin can suppress vascular inflammation induced by high glucose (HG) in human umbilical vein endothelial cells (HUVECs) and mice. Our data indicate that HG markedly increased vascular permeability, monocyte adhesion, the expression of cell adhesion molecules (CAMs), the formation of reactive oxygen species (ROS), and the activation of nuclear factor kappa B (NF-κB). Remarkably, the vascular inflammatory effects of HG were attenuated by pretreatment with orientin. Since vascular inflammation induced by HG is critical in the development of diabetic complications, our results suggest that orientin may have significant benefits in the treatment of diabetic complications and atherosclerosis.

  6. Hyperoside inhibits high-glucose-induced vascular inflammation in vitro and in vivo.

    PubMed

    Ku, Sae-Kwang; Kwak, Soyoung; Kwon, O-Jun; Bae, Jong-Sup

    2014-10-01

    Hyperoside, an active compound from the genera of Hypericum and Crataegus, was reported to have antioxidant, antihyperglycemic, anticancer, anti-inflammatory, and anticoagulant activities. Vascular inflammatory process has been suggested to play a key role in initiation and progression of atherosclerosis, a major complication of diabetes mellitus. Thus, in this study, we attempted to determine whether hyperoside can suppress vascular inflammatory processes induced by high glucose (HG) in human umbilical vein endothelial cells (HUVECs) and mice. Data showed that HG induced markedly increased vascular permeability, monocyte adhesion, expressions of cell adhesion molecules (CAMs), formation of reactive oxygen species (ROS), and activation of nuclear factor (NF)-κB. Remarkably, all of the above-mentioned vascular inflammatory effects of HG were attenuated by pretreatment with hyperoside. Vascular inflammatory responses induced by HG are critical events underlying development of various diabetic complications; therefore, our results suggest that hyperoside may have significant therapeutic benefits against diabetic complications and atherosclerosis.

  7. Inhibition of vascular calcification by block of intermediate conductance calcium-activated potassium channels with TRAM-34.

    PubMed

    Freise, Christian; Querfeld, Uwe

    2014-07-01

    Vascular calcifications are a hallmark of advanced cardiovascular disease in patients with chronic kidney disease. A key event is the transition of contractile vascular smooth muscle cells (VSMC) into an osteoblast-like phenotype, promoting a coordinated process of vascular remodeling resembling bone mineralization. Intermediate-conductance calcium-activated potassium channels (KCa3.1) are expressed in various tissues including VSMC. Aiming for novel therapeutic targets in vascular calcification, we here studied effects of KCa3.1-inhibition on VSMC calcification by the specific KCa3.1 inhibitor TRAM-34. Calcification in the murine VSMC cell line MOVAS-1 and primary rat VSMC was induced by calcification medium (CM) containing elevated levels of PO4(3-) and Ca(2+). Cell signaling, calcification markers, and release of nitric oxide and alkaline phosphatase were assessed by luciferase reporter plasmids, RT-PCR and specific enzymatic assays, respectively. KCa3.1 gene silencing was achieved by siRNA experiments. TRAM-34 at 10nmol/l, decreased CM-induced calcification and induced NO release of VSMC accompanied by decreased TGF-β signaling. The CM-induced mRNA expressions of osterix, osteocalcin, matrix-metalloproteinases (MMP)-2/-9 were reduced by TRAM-34 while osteopontin expression was increased. Further, TRAM-34 attenuated the CM- and TNF-α-induced activation of NF-κB and reduced the release of MMP-2/-9 by VSMC. Finally, TRAM-34 abrogated CM-induced apoptosis and KCa3.1 gene silencing protected VSMC from CM-induced onset of calcification. In summary, TRAM-34 interferes with calcification relevant signaling of NF-κB and TGF-β thereby blocking the phenotypic transition/calcification of VSMC. We conclude that the results provide a rationale for further studies regarding a possible therapeutic role of KCa3.1 inhibition by TRAM-34 or other inhibitors in vascular calcification.

  8. Ionizing irradiation inhibits keloid fibroblast cell proliferation and induces premature cellular senescence.

    PubMed

    Ji, Jiang; Tian, Ye; Zhu, Ya-qun; Zhang, Li-yuan; Ji, Sheng-jun; Huan, Jian; Zhou, Xiao-zhong; Cao, Jian-ping

    2015-01-01

    Keloids are one of the common refractory conditions in dermatology and aesthetic plastic surgery. The most effective treatment is superficial radiotherapy followed by surgical removal. The rate of recurrence is strongly associated with the total dose of ionizing irradiation, and the underlying mechanism remains unclear. In this study, we used primary keloid fibroblasts (KFb) isolated from patient samples to investigate the effects of X-ray radiation on cell proliferation, cell toxicity and cell cycle, as detected by CCK-8 assay kit and flow cytometer. In addition, we examined senescence-associated β-galactosidase activity and the associated gene expression using real-time polymerase chain reaction and western blot in KFb exposed to X-ray radiation. X-ray radiation inhibited cell proliferation and induced cell senescence in KFb in a dose-dependent manner. Inhibition of cell proliferation and induction of cellular senescence were mediated by interruption of the cell cycle with an extended G0/G1 phase. Furthermore, the expressions of senescence-associated genes p21, p16 and p27 were upregulated both at mRNA and protein levels in KFb exposed to X-ray radiation. Taken together, our data indicate that X-ray radiation may prevent the recurrence of keloids by controlling fibroblast proliferation, arresting the cell cycle and inducing premature cellular senescence. © 2014 Japanese Dermatological Association.

  9. Rosuvastatin prevents angiotensin II-induced vascular changes by inhibition of NAD(P)H oxidase and COX-1

    PubMed Central

    Colucci, Rocchina; Fornai, Matteo; Duranti, Emiliano; Antonioli, Luca; Rugani, Ilaria; Aydinoglu, Fatma; Ippolito, Chiara; Segnani, Cristina; Bernardini, Nunzia; Taddei, Stefano; Blandizzi, Corrado; Virdis, Agostino

    2013-01-01

    Background and Purpose NAD(P)H oxidase and COX-1 participate in vascular damage induced by angiotensin II. We investigated the effect of rosuvastatin on endothelial dysfunction, vascular remodelling, changes in extracellular matrix components and mechanical properties of small mesenteric arteries from angiotensin II-infused rats. Experimental Approach Male rats received angiotensin II (120 ng·kg−1·min−1, subcutaneously) for 14 days with or without rosuvastatin (10 mg·kg−1·day−1, oral gavage) or vehicle. Vascular functions and morphological parameters were assessed by pressurized myography. Key Results In angiotensin II-infused rats, ACh-induced relaxation was attenuated compared with controls, less sensitive to L-NAME, enhanced by SC-560 (COX-1 inhibitor) or SQ-29548 (prostanoid TP receptor antagonist), and normalized by the antioxidant ascorbic acid or NAD(P)H oxidase inhibitors. After rosuvastatin, relaxations to ACh were normalized, fully sensitive to L-NAME, and no longer affected by SC-560, SQ-29548 or NAD(P)H oxidase inhibitors. Angiotensin II enhanced intravascular superoxide generation, eutrophic remodelling, collagen and fibronectin depositions, and decreased elastin content, resulting in increased vessel stiffness. All these changes were prevented by rosuvastatin. Angiotensin II increased phosphorylation of NAD(P)H oxidase subunit p47phox and its binding to subunit p67phox, effects inhibited by rosuvastatin. Rosuvastatin down-regulated vascular Nox4/NAD(P)H isoform and COX-1 expression, attenuated the vascular release of 6-keto-PGF1α, and enhanced copper/zinc-superoxide dismutase expression. Conclusion and Implications Rosuvastatin prevents angiotensin II-induced alterations in resistance arteries in terms of function, structure, mechanics and composition. These effects depend on restoration of NO availability, prevention of NAD(P)H oxidase-derived oxidant excess, reversal of COX-1 induction and its prostanoid production, and stimulation of

  10. Triamcinolone Acetonide Selectively Inhibits Angiogenesis in Small Blood Vessels and Decreases Vessel Diameter within the Vascular Tree

    NASA Technical Reports Server (NTRS)

    McKay, Terri L.; Gredeon, Dan J.; Vickerman, Mary B.; Hylton, alan G.; Ribita, Daniela; Olar, Harry H.; Kaiser, Peter K.; Parsons-Wingerter, Patricia

    2007-01-01

    The steroid triamcinolone acetonide (TA) is a potent anti-angiogenesis drug used to treat retinal vascular diseases that include diabetic retinopathy, vascular occlusions and choroidal neovascularization. To quantify the effects of TA on branching morphology within the angiogenic microvascular tree of the chorioallantoic membrane (CAM) of quail embryos. Increasing concentrations of TA (0-16 ng/ml) were applied topically on embryonic day 7 (E7) to the chorioallantoic membrane (CAM) of quail embryos cultured in Petri dishes, and incubated for an additional 24 or 48 hours until fixation. Binary (black/white) microscopic images of arterial end points were quantified by VESGEN software (for Generational Analysis of Vessel Branching) to obtain major vascular parameters that include vessel diameter (Dv), fractal dimension (Df), tortuosity (Tv) and densities of vessel area, length, number and branch point (Av, Lv, Nv and Brv). For assessment of specific changes in vascular morphology induced by TA, the VESGEN software automatically segmented the vascular tree into branching generations (G1...G10) according to changes in vessel diameter and branching. Vessel density decreased significantly up to 34% as the function of increasing concentration of TA according to Av, Lv, Brv, Nv and Df. TA selectively inhibited the growth of new, small vessels, because Lv decreased from 13.14plus or minus 0.61 cm/cm2 for controls to 8.012 plus or minus 0.82 cm/cm2 at 16 ng TA/ml in smaller branching generations (G7-G10), and for Nv from 473.83 plus or minus 29.85 cm(-)2 to 302.32 plus or minus 33.09 cm-()2. In contrast, vessel diameter (Dv) decreased throughout the vascular tree (G1-G10).

  11. In Vivo Imaging Reveals Significant Tumor Vascular Dysfunction and Increased Tumor Hypoxia-Inducible Factor-1α Expression Induced by High Single-Dose Irradiation in a Pancreatic Tumor Model.

    PubMed

    Maeda, Azusa; Chen, Yonghong; Bu, Jiachuan; Mujcic, Hilda; Wouters, Bradly G; DaCosta, Ralph S

    2017-01-01

    To investigate the effect of high-dose irradiation on pancreatic tumor vasculature and microenvironment using in vivo imaging techniques. A BxPC3 pancreatic tumor xenograft was established in a dorsal skinfold window chamber model and a subcutaneous hind leg model. Tumors were irradiated with a single dose of 4, 12, or 24 Gy. The dorsal skinfold window chamber model was used to assess tumor response, vascular function and permeability, platelet and leukocyte adhesion to the vascular endothelium, and tumor hypoxia for up to 14 days after 24-Gy irradiation. The hind leg model was used to monitor tumor size, hypoxia, and vascularity for up to 65 days after 24-Gy irradiation. Tumors were assessed histologically to validate in vivo observations. In vivo fluorescence imaging revealed temporary vascular dysfunction in tumors irradiated with a single dose of 4 to 24 Gy, but most significantly with a single dose of 24 Gy. Vascular functional recovery was observed by 14 days after irradiation in a dose-dependent manner. Furthermore, irradiation with 24 Gy caused platelet and leukocyte adhesion to the vascular endothelium within hours to days after irradiation. Vascular permeability was significantly higher in irradiated tumors compared with nonirradiated controls 14 days after irradiation. This observation corresponded with increased expression of hypoxia-inducible factor-1α in irradiated tumors. In the hind leg model, irradiation with a single dose of 24 Gy led to tumor growth delay, followed by tumor regrowth. Irradiation of the BxPC3 tumors with a single dose of 24 Gy caused transient vascular dysfunction and increased expression of hypoxia-inducible factor-1α. Such biological changes may impact tumor response to high single-dose and hypofractionated irradiation, and further investigations are needed to better understand the clinical outcomes of stereotactic body radiation therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Expression of bone morphogenetic protein, vascular endothelial growth factor, and basic fibroblast growth factor in irradiated mandibles during distraction osteogenesis.

    PubMed

    Zhang, Wen Biao; Zheng, Li Wu; Chua, Daniel Tsin Tien; Cheung, Lim Kwong

    2011-11-01

    The present study evaluated the expression of bone morphogenetic proteins (BMPs)-2, -4, -7, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) in irradiated mandibles during distraction osteogenesis. A total of 24 rabbits were randomly assigned to the control and experimental groups. Each rabbit in the experimental group underwent preoperative radiation to 9 Gy in 5 fractions. After 1 month, all rabbits underwent osteotomy and distraction osteogenesis with 7 days of latency. Three rabbits in the control and experimental groups were killed at day 7 (end of the latency period), day 12 (middle of active distraction), day 18 (end of active distraction), and day 25 (1 week after consolidation). The specimens were used for immunohistochemical staining and real-time polymerase chain reaction analysis. Histologically, at day 25, cortical bone formation was much better in the control group than in the radiotherapy group. In the radiotherapy group, the bone spicules were aligned in the direction of tension stress. At day 12, the expression of BMP-2, -4, and -7 was elevated in the radiotherapy group compared with the control group. At day 25, the expression of BMP-2 was significantly greater in the radiotherapy group. At day 7, the expression of bFGF was significantly suppressed in the radiotherapy group. At day 12, the expression of bFGF and VEGF was significantly elevated in the radiotherapy group compared with the control group. At day 25, the expression of VEGF was significantly greater in the radiotherapy group. The results of our study have shown that radiotherapy changes the expression pattern of BMPs, VEGF, and bFGF. Copyright © 2011. Published by Elsevier Inc.

  13. Low-power laser irradiation inhibits arecoline-induced fibrosis: an in vitro study.

    PubMed

    Yeh, Mei-Chun; Chen, Ker-Kong; Chiang, Min-Hsuan; Chen, Chia-Hsin; Chen, Ping-Ho; Lee, Huey-Er; Wang, Yan-Hsiung

    2017-02-24

    Oral submucous fibrosis (OSF) is a potentially malignant disorder that is characterized by a progressive fibrosis in the oral submucosa. Arecoline, an alkaloid compound of the areca nut, is reported to be a major aetiological factor in the development of OSF. Low-power laser irradiation (LPLI) has been reported to be beneficial in fibrosis prevention in different damaged organs. The aim of this study was to investigate the potential therapeutic effects of LPLI on arecoline-induced fibrosis. Arecoline-stimulated human gingival fibroblasts (HGFs) were treated with or without LPLI. The expression levels of the fibrotic marker genes alpha-smooth muscle actin (α-SMA) and connective tissue growth factor (CTGF/CCN2) were analysed by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) and western blots. In addition, the transcriptional activity of CCN2 was further determined by a reporter assay. The results indicated that arecoline increased the messenger RNA and protein expression of CCN2 and α-SMA in HGF. Interestingly, both LPLI and forskolin, an adenylyl cyclase activator, reduced the expression of arecoline-mediated fibrotic marker genes and inhibited the transcriptional activity of CCN2. Moreover, pretreatment with SQ22536, an adenylyl cyclase inhibitor, blocked LPLI's inhibition of the expression of arecoline-mediated fibrotic marker genes. Our data suggest that LPLI may inhibit the expression of arecoline-mediated fibrotic marker genes via the cAMP signalling pathway.International Journal of Oral Science advance online publication, 24 February 2017; doi:10.1038/ijos.2016.49.

  14. Plumericin inhibits proliferation of vascular smooth muscle cells by blocking STAT3 signaling via S-glutathionylation

    PubMed Central

    Heiss, Elke H; Liu, Rongxia; Waltenberger, Birgit; Khan, Shafaat; Schachner, Daniel; Kollmann, Paul; Zimmermann, Kristin; Cabaravdic, Muris; Uhrin, Pavel; Stuppner, Hermann; Breuss, Johannes M; Atanasov, Atanas G; Dirsch, Verena M

    2016-01-01

    The etiology of atherosclerosis and restenosis involves aberrant inflammation and proliferation, rendering compounds with both anti-inflammatory and anti-mitogenic properties as promising candidates for combatting vascular diseases. A recent study identified the iridoid plumericin as a new scaffold inhibitor of the pro-inflammatory NF-κB pathway in endothelial cells. We here examined the impact of plumericin on the proliferation of primary vascular smooth muscle cells (VSMC). Plumericin inhibited serum-stimulated proliferation of rat VSMC. It arrested VSMC in the G1/G0-phase of the cell cycle accompanied by abrogated cyclin D1 expression and hindered Ser 807/811-phosphorylation of retinoblastoma protein. Transient depletion of glutathione by the electrophilic plumericin led to S-glutathionylation as well as hampered Tyr705-phosphorylation and activation of the transcription factor signal transducer and activator of transcription 3 (Stat3). Exogenous addition of glutathione markedly prevented this inhibitory effect of plumericin on Stat3. It also overcame downregulation of cyclin D1 expression and the reduction of biomass increase upon serum exposure. This study revealed an anti-proliferative property of plumericin towards VSMC which depends on plumericin’s thiol reactivity and S-glutathionylation of Stat3. Hence, plumericin, by targeting at least two culprits of vascular dysfunction –inflammation and smooth muscle cell proliferation -might become a promising electrophilic lead compound for vascular disease therapy. PMID:26858089

  15. Omega-3 and omega-6 DPA equally inhibit the sphingosylphosphorylcholine-induced Ca2+-sensitization of vascular smooth muscle contraction via inhibiting Rho-kinase activation and translocation

    PubMed Central

    Zhang, Ying; Zhang, Min; Lyu, Bochao; Kishi, Hiroko; Kobayashi, Sei

    2017-01-01

    We previously reported that eicosapentaenoic acid (EPA), an omega-3 polyunsaturated fatty acid (n-3 PUFA), effectively inhibits sphingosylphosphorylcholine (SPC)-induced Ca2+-sensitization of vascular smooth muscle (VSM) contraction which is a major cause of cardiovascular and cerebrovascular vasospasm, and EPA is utilized clinically to prevent cerebrovascular vasospasm. In this study, we clearly demonstrate that docosapentaenoic acid (DPA), which exists in two forms as omega-3 (n-3) and omega-6 (n-6) PUFA, strongly inhibits SPC-induced contraction in VSM tissue and human coronary artery smooth muscle cells (CASMCs), with little effect on Ca2+-dependent contraction. Furthermore, n-3 and n-6 DPA inhibited the activation and translocation of Rho-kinase from cytosol to cell membrane. Additionally, SPC-induced phosphorylation of myosin light chain (MLC) was inhibited in n-3 and n-6 DPA pretreated smooth muscleVSM cells and tissues. In summary, we provide direct evidence that n-3 and n-6 DPA effectively equally inhibits SPC-induced contraction by inhibiting Rho-kinase activation and translocation to the cell membrane. PMID:28169288

  16. PEDF improves cardiac function in rats with acute myocardial infarction via inhibiting vascular permeability and cardiomyocyte apoptosis.

    PubMed

    Zhang, Hao; Wang, Zheng; Feng, Shou-Jie; Xu, Lei; Shi, He-Xian; Chen, Li-Li; Yuan, Guang-Da; Yan, Wei; Zhuang, Wei; Zhang, Yi-Qian; Zhang, Zhong-Ming; Dong, Hong-Yan

    2015-03-11

    Pigment epithelium-derived factor (PEDF) is a pleiotropic gene with anti-inflammatory, antioxidant and anti-angiogenic properties. However, recent reports about the effects of PEDF on cardiomyocytes are controversial, and it is not known whether and how PEDF acts to inhibit hypoxic or ischemic endothelial injury in the heart. In the present study, adult Sprague-Dawley rat models of acute myocardial infarction (AMI) were surgically established. PEDF-small interfering RNA (siRNA)-lentivirus (PEDF-RNAi-LV) or PEDF-LV was delivered into the myocardium along the infarct border to knockdown or overexpress PEDF, respectively. Vascular permeability, cardiomyocyte apoptosis, myocardial infarct size and animal cardiac function were analyzed. We also evaluated PEDF's effect on the suppression of the endothelial permeability and cardiomyocyte apoptosis under hypoxia in vitro. The results indicated that PEDF significantly suppressed the vascular permeability and inhibited hypoxia-induced endothelial permeability through PPARγ-dependent tight junction (TJ) production. PEDF protected cardiomyocytes against ischemia or hypoxia-induced cell apoptosis both in vivo and in vitro via preventing the activation of caspase-3. We also found that PEDF significantly reduced myocardial infarct size and enhanced cardiac function in rats with AMI. These data suggest that PEDF could protect cardiac function from ischemic injury, at least by means of reducing vascular permeability, cardiomyocyte apoptosis and myocardial infarct size.

  17. 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

  18. 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

  19. Vascular-derived TGF-β increases in the stem cell niche and perturbs neurogenesis during aging and following irradiation in the adult mouse brain.

    PubMed

    Pineda, Jose R; Daynac, Mathieu; Chicheportiche, Alexandra; Cebrian-Silla, Arantxa; Sii Felice, Karine; Garcia-Verdugo, Jose Manuel; Boussin, François D; Mouthon, Marc-André

    2013-04-01

    Neurogenesis decreases during aging and following cranial radiotherapy, causing a progressive cognitive decline that is currently untreatable. However, functional neural stem cells remained present in the subventricular zone of high dose-irradiated and aged mouse brains. We therefore investigated whether alterations in the neurogenic niches are perhaps responsible for the neurogenesis decline. This hypothesis was supported by the absence of proliferation of neural stem cells that were engrafted into the vascular niches of irradiated host brains. Moreover, we observed a marked increase in TGF-β1 production by endothelial cells in the stem cell niche in both middle-aged and irradiated mice. In co-cultures, irradiated brain endothelial cells induced the apoptosis of neural stem/progenitor cells via TGF-β/Smad3 signalling. Strikingly, the blockade of TGF-β signalling in vivo using a neutralizing antibody or the selective inhibitor SB-505124 significantly improved neurogenesis in aged and irradiated mice, prevented apoptosis and increased the proliferation of neural stem/progenitor cells. These findings suggest that anti-TGF-β-based therapy may be used for future interventions to prevent neurogenic collapse following radiotherapy or during aging.

  20. Effects of electron beam irradiation on physicochemical properties of corn flour and improvement of the gelatinization inhibition.

    PubMed

    Xue, Peiyu; Zhao, Yue; Wen, Chengrong; Cheng, Sheng; Lin, Songyi

    2017-10-15

    The properties and viscosity-reduction mechanism of corn flour irradiated by electron beam have not been understood properly. Here, we investigate the effects of electron beam irradiation (EBI) on the gelatinization and physicochemical properties of corn flour irradiated by 0-5.40kGy of electron beam. The total starch and crude fiber contents of corn flour decreased significantly (P<0.05) after EBI treatment, while the moisture and reducing sugar contents increased significantly (P<0.05). EBI caused perforations on the corn flour particle surfaces, and the irradiated parts of the particles would gradually peel off and afford smooth surfaces, spherical structures, and smaller sizes. Molecular chains of corn flour broke owing to EBI. After irradiation, the pasting peak viscosity decreased dramatically (P<0.01) from 1251.74 to 7.16Pa·s, showing that the gelatinization of corn flour was completely inhibited. Thus, EBI can be used to inhibit the gelatinization of corn flour, which may be beneficial for industrial and food formulations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Tetrahydroxystilbene glucoside inhibits TNF-α-induced migration of vascular smooth muscle cells via suppression of vimentin.

    PubMed

    Yao, Wenjuan; Sun, Qinju; Huang, Lei; Meng, Guoliang; Wang, Huiming; Jing, Xiang; Zhang, Wei

    2015-07-28

    Vascular smooth muscle cell (VSMC) migration triggered by TNF-α is an important event that occurs during the development of atherosclerosis. 2,3,5,4'-Tetrahydroxystilbene-2-O-β-d-glucoside (TSG) has been proven to exhibit significant anti-atherosclerotic activity. Herein we investigate the inhibitory effect of TSG on TNF-α-induced VSMC migration and explore the underlying mechanisms. TSG pretreatment markedly inhibited TNF-α-induced cell migration. The inhibition of vimentin redistribution and expression was involved in the inhibitory effect of TSG on VSMC migration. The suppression of vimentin expression by shRNA in VSMCs significantly inhibited TNF-α-induced cell migration. Furthermore, TSG inhibited the TNF-α-induced expression of TGFβ1 and TGFβR1, and phosphorylation of TGFβR1 and Smad2/3. TSG also suppressed the nuclear translocation of Smad4 induced by TNF-α. These results suggest that TSG inhibits VSMC migration induced by TNF-α through inhibiting vimentin rearrangement and expression. The interruption of TGFβ/Smad pathway appears to be responsible for the suppression of TSG on vimentin expression.

  2. Thrombospondin-1 limits ischemic tissue survival by inhibiting nitric oxide–mediated vascular smooth muscle relaxation

    PubMed Central

    Isenberg, Jeff S.; Hyodo, Fuminori; Matsumoto, Ken-Ichiro; Romeo, Martin J.; Abu-Asab, Mones; Tsokos, Maria; Kuppusamy, Periannan; Wink, David A.; Krishna, Murali C.

    2007-01-01

    The nitric oxide (NO)/cGMP pathway, by relaxing vascular smooth muscle cells, is a major physiologic regulator of tissue perfusion. We now identify thrombospondin-1 as a potent antagonist of NO for regulating F-actin assembly and myosin light chain phosphorylation in vascular smooth muscle cells. Thrombospondin-1 prevents NO-mediated relaxation of precontracted vascular smooth muscle cells in a collagen matrix. Functional magnetic resonance imaging demonstrated that an NO-mediated increase in skeletal muscle perfusion was enhanced in thrombospondin-1–null relative to wild-type mice, implicating endogenous thrombospondin-1 as a physiologic antagonist of NO-mediated vasodilation. Using a random myocutaneous flap model for ischemic injury, tissue survival was significantly enhanced in thrombospondin-1–null mice. Improved flap survival correlated with increased recovery of oxygen levels in the ischemic tissue of thrombospondin-1–null mice as measured by electron paramagnetic resonance oximetry. These findings demonstrate an important antag-onistic relation between NO/cGMP signaling and thrombospondin-1 in vascular smooth muscle cells to regulate vascular tone and tissue perfusion. PMID:17082319

  3. Cerebral cavernous malformations proteins inhibit Rho kinase to stabilize vascular integrity

    PubMed Central

    Stockton, Rebecca A.; Shenkar, Robert; Awad, Issam A.

    2010-01-01

    Endothelial cell–cell junctions regulate vascular permeability, vasculogenesis, and angiogenesis. Familial cerebral cavernous malformations (CCMs) in humans result from mutations of CCM2 (malcavernin, OSM, MGC4607), PDCD10 (CCM3), or KRIT1 (CCM1), a Rap1 effector which stabilizes endothelial cell–cell junctions. Homozygous loss of KRIT1 or CCM2 produces lethal vascular phenotypes in mice and zebrafish. We report that the physical interaction of KRIT1 and CCM2 proteins is required for endothelial cell–cell junctional localization, and lack of either protein destabilizes barrier function by sustaining activity of RhoA and its effector Rho kinase (ROCK). Protein haploinsufficient Krit1+/− or Ccm2+/− mouse endothelial cells manifested increased monolayer permeability in vitro, and both Krit1+/− and Ccm2+/− mice exhibited increased vascular leak in vivo, reversible by fasudil, a ROCK inhibitor. Furthermore, we show that ROCK hyperactivity occurs in sporadic and familial human CCM endothelium as judged by increased phosphorylation of myosin light chain. These data establish that KRIT1–CCM2 interaction regulates vascular barrier function by suppressing Rho/ROCK signaling and that this pathway is dysregulated in human CCM endothelium, and they suggest that fasudil could ameliorate both CCM disease and vascular leak. PMID:20308363

  4. Cerebral cavernous malformations proteins inhibit Rho kinase to stabilize vascular integrity.

    PubMed

    Stockton, Rebecca A; Shenkar, Robert; Awad, Issam A; Ginsberg, Mark H

    2010-04-12

    Endothelial cell-cell junctions regulate vascular permeability, vasculogenesis, and angiogenesis. Familial cerebral cavernous malformations (CCMs) in humans result from mutations of CCM2 (malcavernin, OSM, MGC4607), PDCD10 (CCM3), or KRIT1 (CCM1), a Rap1 effector which stabilizes endothelial cell-cell junctions. Homozygous loss of KRIT1 or CCM2 produces lethal vascular phenotypes in mice and zebrafish. We report that the physical interaction of KRIT1 and CCM2 proteins is required for endothelial cell-cell junctional localization, and lack of either protein destabilizes barrier function by sustaining activity of RhoA and its effector Rho kinase (ROCK). Protein haploinsufficient Krit1(+/-) or Ccm2(+/-) mouse endothelial cells manifested increased monolayer permeability in vitro, and both Krit1(+/-) and Ccm2(+/-) mice exhibited increased vascular leak in vivo, reversible by fasudil, a ROCK inhibitor. Furthermore, we show that ROCK hyperactivity occurs in sporadic and familial human CCM endothelium as judged by increased phosphorylation of myosin light chain. These data establish that KRIT1-CCM2 interaction regulates vascular barrier function by suppressing Rho/ROCK signaling and that this pathway is dysregulated in human CCM endothelium, and they suggest that fasudil could ameliorate both CCM disease and vascular leak.

  5. 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.

  6. Orphan Nuclear Receptor Nur77 Inhibits Angiotensin II-Induced Vascular Remodeling via Downregulation of β-Catenin.

    PubMed

    Cui, Mingli; Cai, Zhaohua; Chu, Shichun; Sun, Zhe; Wang, Xiaolei; Hu, Liuhua; Yi, Jing; Shen, Linghong; He, Ben

    2016-01-01

    Angiotensin II (Ang II) is the predominant effector peptide of the renin-angiotensin system. Ang II contributes to vascular remodeling in many cardiovascular diseases (eg, hypertension, atherosclerosis, restenosis, and aneurysm). Orphan nuclear receptor Nur77 has a crucial role in the functional regulation of vascular cells. The objective of this study was to define the specific role of Nur77 in Ang II-induced vascular remodeling. Nur77 expression was initially found to be elevated in medial vascular smooth muscle cells (VSMCs) of thoracic aortas from mice continuously infused with Ang II for 2 weeks using a subcutaneous osmotic minipump. Cellular studies revealed that Nur77 expression was upregulated by Ang II via the MAPK/PKA-CREB signaling pathway. Ang II-induced proliferation, migration, and phenotypic switching were significantly enhanced in VSMCs isolated from Nur77(-/-) mice compared with wild-type VSMCs. Consistent with the role in VSMCs, we found that compared with wild-type mice, Nur77(-/-) mice had elevated aortic medial areas and luminal diameters, more severe elastin disruption and collagen deposition, increased VSMC proliferation and matrix metalloproteinase production, and decreased VSMC-specific genes SM-22α and α-actin expression, after 2 weeks of exogenous Ang II administration. The results of additional experiments suggested that Nur77 suppressed Ang II-induced β-catenin signaling pathway activation by promoting β-catenin degradation and inhibiting its transcriptional activity. Our findings indicated that Nur77 is a critical negative regulator of Ang II-induced VSMC proliferation, migration, and phenotypic switching via the downregulation of β-catenin activity. Nur77 may reduce Ang II-induced vascular remodeling involved in many cardiovascular diseases. © 2015 American Heart Association, Inc.

  7. Aphidicolin does not inhibit DNA repair synthesis in ultraviolet-irradiated HeLa cells. A radioautographic study.

    PubMed Central

    Hardt, N; Pedrali-Noy, G; Focher, F; Spadari, S

    1981-01-01

    A radioautographic examination of nuclear DNA synthesis in unirradiated and u.v.-irradiated HeLa cells, in the presence and in the absence of aphidicolin, showed that aphidicolin inhibits nuclear DNA replication and has no detectable effect on DNA repair synthesis. Although the results establish that in u.v.-irradiated HeLa cells most of the DNA repair synthesis is not due to DNA polymerase alpha, they do not preclude a significant role for this enzyme in DNA repair processes. Images PLATE 1 PMID:6803764

  8. Transient Inhibition of Transforming Growth Factor-β1 in Human Diabetic CD34+ Cells Enhances Vascular Reparative Functions

    PubMed Central

    Bhatwadekar, Ashay D.; Guerin, E.P.; Jarajapu, Yagna P.R.; Caballero, Sergio; Sheridan, Carl; Kent, David; Kennedy, Laurence; Lansang, M. Cecilia; Ruscetti, Frank W.; Pepine, Carl J.; Higgins, Paul J.; Bartelmez, Stephen H.; Grant, Maria B.

    2010-01-01

    OBJECTIVE Peripheral blood CD34+ cells from diabetic patients demonstrate reduced vascular reparative function due to decreased proliferation and diminished migratory prowess, largely resulting from decreased nitric oxide (NO) bioavailability. The level of TGF-β, a key factor that modulates stem cell quiescence, is increased in the serum of type 2 diabetic patients. We asked whether transient TGF-β1 inhibition in CD34+ cells would improve their reparative ability. RESEARCH DESIGN AND METHODS To inhibit TGF-β1 protein expression, CD34+ cells were treated ex vivo with antisense phosphorodiamidate morpholino oligomers (TGF-β1-PMOs) and analyzed for cell surface CXCR4 expression, cell survival in the absence of added growth factors, SDF-1-induced migration, NO release, and in vivo retinal vascular reparative ability. RESULTS TGF-β1-PMO treatment of diabetic CD34+ cells resulted in increased expression of CXCR4, enhanced survival in the absence of growth factors, and increased migration and NO release as compared with cells treated with control PMO. Using a retinal ischemia reperfusion injury model in mice, we observed that recruitment of diabetic CD34+ cells to injured acellular retinal capillaries was greater after TGF-β1-PMO treatment compared with control PMO–treated cells. CONCLUSIONS Transient inhibition of TGF-β1 may represent a promising therapeutic strategy for restoring the reparative capacity of dysfunctional diabetic CD34+ cells. PMID:20460428

  9. Arginase inhibition prevents bleomycin-induced pulmonary hypertension, vascular remodeling, and collagen deposition in neonatal rat lungs.

    PubMed

    Grasemann, Hartmut; Dhaliwal, Rupinder; Ivanovska, Julijana; Kantores, Crystal; McNamara, Patrick J; Scott, Jeremy A; Belik, Jaques; Jankov, Robert P

    2015-03-15

    Arginase is an enzyme that limits substrate L-arginine bioavailability for the production of nitric oxide by the nitric oxide synthases and produces L-ornithine, which is a precursor for collagen formation and tissue remodeling. We studied the pulmonary vascular effects of arginase inhibition in an established model of repeated systemic bleomycin sulfate administration in neonatal rats that results in pulmonary hypertension and lung injury mimicking the characteristics typical of bronchopulmonary dysplasia. We report that arginase expression is increased in the lungs of bleomycin-exposed neonatal rats and that treatment with the arginase inhibitor amino-2-borono-6-hexanoic acid prevented the bleomycin-induced development of pulmonary hypertension and deposition of collagen. Arginase inhibition resulted in increased L-arginine and L-arginine bioavailability and increased pulmonary nitric oxide production. Arginase inhibition also normalized the expression of inducible nitric oxide synthase, and reduced bleomycin-induced nitrative stress while having no effect on bleomycin-induced inflammation. Our data suggest that arginase is a promising target for therapeutic interventions in neonates aimed at preventing lung vascular remodeling and pulmonary hypertension.

  10. Inhibiting the Aurora B Kinase Potently Suppresses Repopulation During Fractionated Irradiation of Human Lung Cancer Cell Lines

    SciTech Connect

    Sak, Ali; Stuschke, Martin; Groneberg, Michael; Kuebler, Dennis; Poettgen, Christoph; Eberhardt, Wilfried E.E.

    2012-10-01

    Purpose: The use of molecular-targeted agents during radiotherapy of non-small-cell lung cancer (NSCLC) is a promising strategy to inhibit repopulation, thereby improving therapeutic outcome. We assessed the combined effectiveness of inhibiting Aurora B kinase and irradiation on human NSCLC cell lines in vitro. Methods and Materials: NSCLC cell lines were exposed to concentrations of AZD1152-hydroxyquinazoline pyrazol anilide (AZD1152-HQPA) inhibiting colony formation by 50% (IC50{sub clone}) in combination with single dose irradiation or different fractionation schedules using multiple 2-Gy fractions per day up to total doses of 4-40 Gy. The total irradiation dose required to control growth of 50% of the plaque monolayers (TCD50) was determined. Apoptosis, G2/M progression, and polyploidization were also analyzed. Results: TCD50 values after single dose irradiation were similar for the H460 and H661 cell lines with 11.4 {+-} 0.2 Gy and 10.7 {+-} 0.3 Gy, respectively. Fractionated irradiation using 3 Multiplication-Sign 2 Gy/day, 2 Multiplication-Sign 2 Gy/day, and 1 Multiplication-Sign 2 Gy/day schedules significantly increased TCD50 values for both cell lines grown as plaque monolayers with increasing radiation treatment time. This could be explained by a repopulation effect per day that counteracts 75 {+-} 8% and 27 {+-} 6% of the effect of a 2-Gy fraction in H460 and H661 cells, respectively. AZD1152-HQPA treatment concomitant to radiotherapy significantly decreased the daily repopulation effect (H460: 28 {+-} 5%, H661: 10 {+-} 4% of a 2-Gy fraction per day). Treatment with IC50{sub clone} AZD1152-HPQA did not induce apoptosis, prolong radiation-induced G2 arrest, or delay cell cycle progression before the spindle check point. However, polyploidization was detected, especially in cell lines without functional p53. Conclusions: Inhibition of Aurora B kinase with low AZD1152-HQPA concentrations during irradiation of NSCLC cell lines affects repopulation during

  11. Liposomal prednisolone inhibits vascular inflammation and enhances venous outward remodeling in a murine arteriovenous fistula model.

    PubMed

    Wong, ChunYu; Bezhaeva, Taisiya; Rothuizen, Tonia C; Metselaar, Josbert M; de Vries, Margreet R; Verbeek, Floris P R; Vahrmeijer, Alexander L; Wezel, Anouk; van Zonneveld, Anton-Jan; Rabelink, Ton J; Quax, Paul H A; Rotmans, Joris I

    2016-07-27

    Arteriovenous fistulas (AVF) for hemodialysis access have a 1-year primary patency rate of only 60%, mainly as a result of maturation failure that is caused by insufficient outward remodeling and intimal hyperplasia. The exact pathophysiology remains unknown, but the inflammatory vascular response is thought to play an important role. In the present study we demonstrate that targeted liposomal delivery of prednisolone increases outward remodeling of the AVF in a murine model. Liposomes accumulate in the post-anastomotic area of the venous outflow tract in which the vascular pathology is most prominent in failed AVFs. On a histological level, we observed a reduction of lymphocytes and granulocytes in the vascular wall. In addition, a strong anti-inflammatory effect of liposomal prednisolone on macrophages was demonstrated in vitro. Therefore, treatment with liposomal prednisolone might be a valuable strategy to improve AVF maturation.

  12. Liposomal prednisolone inhibits vascular inflammation and enhances venous outward remodeling in a murine arteriovenous fistula model

    PubMed Central

    Wong, ChunYu; Bezhaeva, Taisiya; Rothuizen, Tonia C.; Metselaar, Josbert M.; de Vries, Margreet R.; Verbeek, Floris P. R.; Vahrmeijer, Alexander L.; Wezel, Anouk; van Zonneveld, Anton-Jan; Rabelink, Ton J.; Quax, Paul H. A.; Rotmans, Joris I.

    2016-01-01

    Arteriovenous fistulas (AVF) for hemodialysis access have a 1-year primary patency rate of only 60%, mainly as a result of maturation failure that is caused by insufficient outward remodeling and intimal hyperplasia. The exact pathophysiology remains unknown, but the inflammatory vascular response is thought to play an important role. In the present study we demonstrate that targeted liposomal delivery of prednisolone increases outward remodeling of the AVF in a murine model. Liposomes accumulate in the post-anastomotic area of the venous outflow tract in which the vascular pathology is most prominent in failed AVFs. On a histological level, we observed a reduction of lymphocytes and granulocytes in the vascular wall. In addition, a strong anti-inflammatory effect of liposomal prednisolone on macrophages was demonstrated in vitro. Therefore, treatment with liposomal prednisolone might be a valuable strategy to improve AVF maturation. PMID:27460883

  13. Heme oxygenase-1 gene delivery by Sleeping Beauty inhibits vascular stasis in a murine model of sickle cell disease.

    PubMed

    Belcher, John D; Vineyard, Julie V; Bruzzone, Carol M; Chen, Chunsheng; Beckman, Joan D; Nguyen, Julia; Steer, Clifford J; Vercellotti, Gregory M

    2010-07-01

    Increases in heme oxygenase-1 (HO-1) and administration of heme degradation products CO and biliverdin inhibit vascular inflammation and vasoocclusion in mouse models of sickle cell disease (SCD). In this study, an albumin (alb) promoter-driven Sleeping Beauty (SB) transposase plasmid with a wild-type rat hmox-1 (wt-HO-1) transposable element was delivered by hydrodynamic tail vein injections to SCD mice. Eight weeks after injection, SCD mice had three- to five-fold increases in HO-1 activity and protein expression in liver, similar to hemin-treated mice. Immunohistochemistry demonstrated increased perinuclear HO-1 staining in hepatocytes. Messenger RNA transcription of the hmox-1 transgene in liver was confirmed by quantitative real-time polymerase chain reaction restriction fragment length polymorphism (qRT-PCR RFLP) with no detectible transgene expression in other organs. The livers of all HO-1 overexpressing mice had activation of nuclear phospho-p38 mitogen-activated protein kinase (MAPK) and phospho-Akt, decreased nuclear expression of nuclear factor-kappa B (NF-kappaB) p65, and decreased soluble vascular cell adhesion molecule-1 (sVCAM-1) in serum. Hypoxia-induced stasis, a characteristic of SCD, but not normal mice, was inhibited in dorsal skin fold chambers in wt-HO-1 SCD mice despite the absence of hmox-1 transgene expression in the skin suggesting distal effects of HO activity on the vasculature. No protective effects were seen in SCD mice injected with nonsense (ns-) rat hmox-1 that encodes carboxy-truncated HO-1 with little or no enzyme activity. We speculate that HO-1 gene delivery to the liver is beneficial in SCD mice by degrading pro-oxidative heme, releasing anti-inflammatory heme degradation products CO and biliverdin/bilirubin into circulation, activating cytoprotective pathways and inhibiting vascular stasis at sites distal to transgene expression.

  14. Vasorelaxation induced by dodoneine is mediated by calcium channels blockade and carbonic anhydrase inhibition on vascular smooth muscle cells.

    PubMed

    Carre, Grégoire; Ouedraogo, Maurice; Magaud, Christophe; Carreyre, Hélène; Becq, Frédéric; Bois, Patrick; Supuran, Claudiu T; Thibaudeau, Sébastien; Vandebrouck, Clarisse; Bescond, Jocelyn

    2015-07-01

    Dodoneine (Ddn) is one of the active compounds identified from Agelanthus dodoneifolius (DC.) Polhill and Wiens, a medicinal plant used in traditional medicine for the treatment of hypertension. This dihydropyranone exerts hypotensive and vasorelaxant effects on rats, and two molecular targets have been characterized: the carbonic anhydrase and the L-type calcium channel in cardiomyocytes with biochemical and electrophysiological techniques, respectively. To further evaluate the involvement of these two molecular targets in vasorelaxation, the effect of Ddn on rat vascular smooth muscle was investigated. The effects of Ddn on L-type calcium current and on resting membrane potential were characterized in A7r5 cell line using the whole-cell patch-clamp configuration. The molecular identities of carbonic anhydrase isozymes in smooth muscle cells were examined with RT-PCR. Vascular response was measured on rat aortic rings in an organ bath apparatus and the effect of Ddn on intracellular pH was determined by flow cytometry using the pH-sensitive fluorescent probe BCECF-AM [2,7-Bis-(2-Carboxyethyl)-5-(and-6)-Carboxyfluorescein, Acetoxymethyl Ester]. 100µM Ddn reduced calcium current density of about 30%. In addition, carbonic anhydrase II, III, XIII and XIV were shown to be expressed in rat aorta and inhibited in smooth muscle cells by Ddn. This inhibition resulted in a rise in pHi of about 0.31, leading to KCa channel activation, thereby inducing membrane hyperpolarization and vasorelaxation. The results of vascular reactivity experiments obtained with pharmacological tools acting on the L-type calcium current and carbonic anhydrase suggest that Ddn produces its vasorelaxant effect via the inhibition of these two molecular targets. This study demonstrates that Ddn induced vasorelaxation by targeting two proteins involved in the modulation of excitation-contraction coupling: L-type calcium channels and carbonic anhydrase. Copyright © 2015 Elsevier Ireland Ltd. All

  15. Heme oxygenase-1 gene delivery by Sleeping Beauty inhibits vascular stasis in a murine model of sickle cell disease

    PubMed Central

    Belcher, John D.; Vineyard, Julie V.; Bruzzone, Carol M.; Chen, Chunsheng; Beckman, Joan D.; Nguyen, Julia; Steer, Clifford J.

    2010-01-01

    Increases in heme oxygenase-1 (HO-1) and administration of heme degradation products CO and biliverdin inhibit vascular inflammation and vasoocclusion in mouse models of sickle cell disease (SCD). In this study, an albumin (alb) promoter-driven Sleeping Beauty (SB) transposase plasmid with a wild-type rat hmox-1 (wt-HO-1) transposable element was delivered by hydrodynamic tail vein injections to SCD mice. Eight weeks after injection, SCD mice had three- to five-fold increases in HO-1 activity and protein expression in liver, similar to hemin-treated mice. Immunohistochemistry demonstrated increased perinuclear HO-1 staining in hepatocytes. Messenger RNA transcription of the hmox-1 transgene in liver was confirmed by quantitative real-time polymerase chain reaction restriction fragment length polymorphism (qRT-PCR RFLP) with no detectible transgene expression in other organs. The livers of all HO-1 overexpressing mice had activation of nuclear phospho-p38 mitogen-activated protein kinase (MAPK) and phospho-Akt, decreased nuclear expression of nuclear factor-kappa B (NF-κB) p65, and decreased soluble vascular cell adhesion molecule-1 (sVCAM-1) in serum. Hypoxia-induced stasis, a characteristic of SCD, but not normal mice, was inhibited in dorsal skin fold chambers in wt-HO-1 SCD mice despite the absence of hmox-1 transgene expression in the skin suggesting distal effects of HO activity on the vasculature. No protective effects were seen in SCD mice injected with nonsense (ns-) rat hmox-1 that encodes carboxy-truncated HO-1 with little or no enzyme activity. We speculate that HO-1 gene delivery to the liver is beneficial in SCD mice by degrading pro-oxidative heme, releasing anti-inflammatory heme degradation products CO and biliverdin/bilirubin into circulation, activating cytoprotective pathways and inhibiting vascular stasis at sites distal to transgene expression. PMID:20306336

  16. Inhibition of bone morphogenetic protein signal transduction prevents the medial vascular calcification associated with matrix Gla protein deficiency.

    PubMed

    Malhotra, Rajeev; Burke, Megan F; Martyn, Trejeeve; Shakartzi, Hannah R; Thayer, Timothy E; O'Rourke, Caitlin; Li, Pingcheng; Derwall, Matthias; Spagnolli, Ester; Kolodziej, Starsha A; Hoeft, Konrad; Mayeur, Claire; Jiramongkolchai, Pawina; Kumar, Ravindra; Buys, Emmanuel S; Yu, Paul B; Bloch, Kenneth D; Bloch, Donald B

    2015-01-01

    Matrix Gla protein (MGP) is reported to inhibit bone morphogenetic protein (BMP) signal transduction. MGP deficiency is associated with medial calcification of the arterial wall, in a process that involves both osteogenic transdifferentiation of vascular smooth muscle cells (VSMCs) and mesenchymal transition of endothelial cells (EndMT). In this study, we investigated the contribution of BMP signal transduction to the medial calcification that develops in MGP-deficient mice. MGP-deficient mice (MGP(-/-)) were treated with one of two BMP signaling inhibitors, LDN-193189 or ALK3-Fc, beginning one day after birth. Aortic calcification was assessed in 28-day-old mice by measuring the uptake of a fluorescent bisphosphonate probe and by staining tissue sections with Alizarin red. Aortic calcification was 80% less in MGP(-/-) mice treated with LDN-193189 or ALK3-Fc compared with vehicle-treated control animals (P<0.001 for both). LDN-193189-treated MGP(-/-) mice survived longer than vehicle-treated MGP(-/-) mice. Levels of phosphorylated Smad1/5 and Id1 mRNA (markers of BMP signaling) did not differ in the aortas from MGP(-/-) and wild-type mice. Markers of EndMT and osteogenesis were increased in MGP(-/-) aortas, an effect that was prevented by LDN-193189. Calcification of isolated VSMCs was also inhibited by LDN-193189. Inhibition of BMP signaling leads to reduced vascular calcification and improved survival in MGP(-/-) mice. The EndMT and osteogenic transdifferentiation associated with MGP deficiency is dependent upon BMP signaling. These results suggest that BMP signal transduction has critical roles in the development of vascular calcification in MGP-deficient mice.

  17. Low-power laser irradiation of blood inhibits platelet function: role of cyclic GMP

    NASA Astrophysics Data System (ADS)

    Brill, Alexander G.; Brill, Gregory E.; Shenkman, Boris; Tamarin, Ilya; Dardik, Rima; Varon, David; Savion, Naphtali

    1998-12-01

    The aim of the present work was to investigate effect of low power laser irradiation (LPLI) on platelet function in vitro. He-Ne laser (Optronix, USA; (lambda) - 632.8 nm, output power - 7 mW) was employed. Platelet adhesion and aggregation in whole blood (WB) under defined shear conditions were assayed by a Cone and Plate(let) Analyzer. Platelet activation was evaluated by flow cytometry. Level of platelet cGMP was estimated by immunoenzyme assay. Experiments performed showed that LPLI of WB resulted in decrease of platelet deposition on extracellular matrix at high shear rate (1300 s-1). Similar results were obtained using surfaces precoated with either collagen type I or von Willebrand factor. LPLI inhibited fibrinogen binding as well as P-selectin expression on the platelet membrane, induced by thrombin analogue. It was found out that primary acceptor of laser energy responsible for the effect on platelets was located in platelets themselves and not in blood plasma or in other blood cells. LPLI of gel- filtered platelets resulted in increase of intracellular level of cGMP both in the absence and in presence of izobutylmethylxantine (phosphodiesterase inhibitor) suggesting stimulation of synthesis rather than destruction of cGMP under the influence of LPLI. It is suggested that guanylate cyclase and/or NO-synthase might serve as primary acceptors of He-Ne laser light in platelets.

  18. Human Apurinic/Apyrimidinic Endonuclease siRNA Inhibits the Angiogenesis Induced by X-Ray Irradiation in Lung Cancer Cells

    PubMed Central

    Gu, Xianqing; Cun, Yanping; Li, Mengxia; Qing, Yi; Jin, Feng; Zhong, Zhaoyang; Dai, Nan; Qian, Chengyuan; Sui, Jiangdong; Wang, Dong

    2013-01-01

    Objective: Radiotherapy is an important and effective treatment method for non-small cell lung cancer (NSCLC). Nonetheless, radiotherapy can alter the expression of proangiogenic molecules and induce angiogenesis. Human apurinic/apyrimidinic endonuclease (APE1) is a multifunctional protein, which has DNA repair and redox function. Our previous studies indicated APE1 is also a crucial angiogenic regulator. Thus, we investigated the effect of APE1 on radiation-induced angiogenesis in lung cancer and its underlying mechanism. Methods: Tumor specimens of 136 patients with NSCLC were obtained from 2003 to 2008. The APE1 and vascular endothelial growth factor (VEGF) expression, as well as microvessel density (MVD) were observed with immunohistochemistry in tumor samples. Human lung adenocarcinoma A549 cells were treated with Ad5/F35-APE1 siRNA and/or irradiation, and then the cells were used for APE1 analysis by Western blot and VEGF analysis by RT-PCR and ELISA. To elucidate the underline mechanism of APE1 on VEGF expression, HIF-1α protein level was determined by Western blot, and the DNA binding activity of HIF-1α was detected by EMSA. Transwell migration assay and capillary-like structure assay were used to observe the migration and capillary-like structure formation ability of human umbilical veins endothelial cells (HUVECs) that were co-cultured with Ad5/F35-APE1 siRNA and (or) irradiation treated A549 cells culture medium. Results: The high expression rates of APE1 and VEGF in NSCLC were 77.94% and 66.18%, respectively. The expressions of APE1 was significantly correlated with VEGF and MVD (r=0.369, r=0.387). APE1 and VEGF high expression were significantly associated with reduced disease free survival (DFS) time. The high expressions of APE1 and VEGF on A549 cells were concurrently induced by X-ray irradiation in a dose-dependent manner. Silencing of APE1 by Ad5/F35-APE1 siRNA significantly decreased DNA binding activity of HIF-1α and suppressed the expression

  19. Vasoinhibins: a family of N-terminal prolactin fragments that inhibit angiogenesis and vascular function.

    PubMed

    Clapp, Carmen; González, Carmen; Macotela, Yazmín; Aranda, Jorge; Rivera, José C; García, Celina; Guzmán, Jessica; Zamorano, Miriam; Vega, Claudia; Martín, Cecilia; Jeziorski, Michael C; de la Escalera, Gonzalo Martínez

    2006-01-01

    Antiangiogenic molecules derived from prolactin (PRL) are not a single entity, but rather a family of peptides with different molecular masses, all containing the N-terminal region of PRL. Cleavage of PRL by cathepsin-D or by matrix metalloproteases generates N-terminal fragments that act on endothelial cells to suppress vasodilation and angiogenesis and promote vascular regression. N-terminal PRL fragments have been identified in cartilage and retina, where angiogenesis is highly restricted. In vivo experiments demonstrate that these PRL fragments exert a tonic and essential suppression of retinal blood vessel growth and dilation. Similar PRL fragments have been detected in the pituitary gland, a highly vascularized organ where the control of vascular growth may differ from that in tissues where angiogenesis is highly restricted. We have previously proposed the name vasoinhibins to describe the collection of N-terminal PRL fragments having blood vessel-blocking activity, and here we discuss their promise as factors to control vascular function in health and disease.

  20. Hydroxy-oleic acid, but not oleic acid, inhibits vascular responsiveness in isolated aortic tissue

    EPA Science Inventory

    Oleic acid (OA) and other fatty acids can become abundant in circulation after air pollution exposure as endogenously released lipolysis byproducts or by entering the body as a component of air pollution. Vascular damage has been observed with OA infusion, but it is not yet estab...

  1. Hydroxy-oleic acid, but not oleic acid, inhibits vascular responsiveness in isolated aortic tissue

    EPA Science Inventory

    Oleic acid (OA) and other fatty acids can become abundant in circulation after air pollution exposure as endogenously released lipolysis byproducts or by entering the body as a component of air pollution. Vascular damage has been observed with OA infusion, but it is not yet estab...

  2. Hydroxy-oleic acid, but not oleic acid, inhibits pharmacologic vascular responsiveness in isolated aortic tissue

    EPA Science Inventory

    Oleic acid (OA) and other fatty acids can become abundant in the systemic circulation after air pollution exposure as endogenously released lipolysis byproducts or by entering the body as a component of air pollution. Vascular damage has been observed with OA infusion, but it is ...

  3. Reduction of endoplasmic reticulum stress inhibits neointima formation after vascular injury.

    PubMed

    Ishimura, Shutaro; Furuhashi, Masato; Mita, Tomohiro; Fuseya, Takahiro; Watanabe, Yuki; Hoshina, Kyoko; Kokubu, Nobuaki; Inoue, Katsumi; Yoshida, Hideaki; Miura, Tetsuji

    2014-11-06

    Endoplasmic reticulum (ER) stress and inappropriate adaptation through the unfolded protein response (UPR) are predominant features of pathological processes. However, little is known about the link between ER stress and endovascular injury. We investigated the involvement of ER stress in neointima hyperplasia after vascular injury. The femoral arteries of 7-8-week-old male mice were subjected to wire-induced vascular injury. After 4 weeks, immunohistological analysis showed that ER stress markers were upregulated in the hyperplastic neointima. Neointima formation was increased by 54.8% in X-box binding protein-1 (XBP1) heterozygous mice, a model of compromised UPR. Knockdown of Xbp1 in human coronary artery smooth muscle cells (CASMC) in vitro promoted cell proliferation and migration. Furthermore, treatment with ER stress reducers, 4-phenylbutyrate (4-PBA) and tauroursodeoxycholic acid (TUDCA), decreased the intima-to-media ratio after wire injury by 50.0% and 72.8%, respectively. Chronic stimulation of CASMC with PDGF-BB activated the UPR, and treatment with 4-PBA and TUDCA significantly suppressed the PDGF-BB-induced ER stress markers in CASMC and the proliferation and migration of CASMC. In conclusion, increased ER stress contributes to neointima formation after vascular injury, while UPR signaling downstream of XBP1 plays a suppressive role. Suppression of ER stress would be a novel strategy against post-angioplasty vascular restenosis.

  4. Indirect co‑culture of vascular smooth muscle cells with bone marrow mesenchymal stem cells inhibits vascular calcification and downregulates the Wnt signaling pathways.

    PubMed

    Zhu, Meng'en; Fang, Xin; Zhou, Shaoqiong; Li, Wei; Guan, Siming

    2016-06-01

    Vascular calcification (VC) is widely considered to be a crucial clinical indicator of cardiovascular disease. Recently, certain properties of mesenchymal stem cells (MSCs) have been hypothesized to have potential in treating cardiovascular diseases. However, their effect on the initiation and progression of VC remains controversial. The present study aimed to investigate whether MSCs indirectly mediate VC and their impact on the Wnt signaling pathways. A Transwell system was selected to establish the indirect co‑culture environment, and hence, vascular smooth muscle cells (VSMCs) were indirectly co‑cultured in the presence or absence of MSCs at a ratio of 1:1. Osteogenic medium (OS) was added to imitate a calcifying environment. Fourteen days later, VSMCs in the lower layers of the Transwell plates were harvested. Alkaline phosphatase activity and calcium nodules were markedly increased in calcific VSMCs induced by OS. However, these parameters were significantly decreased in VSMCs by indirectly co‑culturing with MSCs in the same medium. Furthermore, the messenger RNA expression levels of osteopontin and osteoprotegerin were notably increased in VSMCs cultured in OS, but reduced by indirect interaction with MSCs. In addition, the activities of canonical and noncanonical Wnt ligands, wingless‑type MMTV integration site family, number 5A (Wnt5a), receptor tyrosine kinase‑like orphan receptor 2 (Ror2) and β‑catenin, which are important in the process of VC, were downregulated by indirect contact with MSCs in OS. Thus, indirect co‑culture with MSCs inhibits VC and downregulates the Wnt signaling pathways.

  5. Oxidants downstream from superoxide inhibit nitric oxide production by vascular endothelium--a key role for selenium-dependent enzymes in vascular health.

    PubMed

    McCarty, M F

    1999-10-01

    Although superoxide can directly quench endothelium-generated nitric oxide (NO), there is considerable evidence that oxidants derived from superoxide--notably peroxides and their further derivatives--can also impair NO bioactivity. In part, this reflects inhibition of NO synthase activity, perhaps mediated by the oxidation of labile sulfhydryl groups, as well as the activation of protein kinase C. Selenium deficiency exacerbates these effects, presumably owing to the crucial role of selenium-dependent thioredoxin reductase and glutathione peroxidases in preventing and reversing oxidant damage to proteins. High-normal homocyst(e)ine levels may induce an 'effective selenium deficiency' by suppressing glutathione peroxidase transcription in endothelial cells. Considerable epidemiology, primarily of European origin, points to mediocre selenium nutrition as a significant vascular risk factor; the risk associated with elevated plasma homocyst(e)ine levels is now well established. In addition to preventing LDL oxidation, vitamin E can be expected to minimize the contribution of lipid peroxides to endothelial dysfunction. Lipoic acid, which can function in vivo as a versatile antioxidant and sulfhydryl reductant, may have particular value for protecting endothelium from oxidants; its clinical utility in diabetic neuropathy may reflect this benefit. Good selenium status, as well as supra-nutritional intakes of lipoic acid, may down-regulate cytokine-mediated endothelial activation by helping to maintain the proper structure of oxidant-labile proteins--such as tyrosine phosphatases--that modulate this signaling. It can be concluded that a number of supplemental nutrients--including selenium, vitamin E, lipoic acid, and the vitamins that promote catabolism of homocysteine--have the potential to promote vascular health by mitigating the adverse impact of superoxide-derived oxidants on endothelial function.

  6. Silencing of osterix expression by siRNA inhibits aldosterone‑induced calcification of vascular smooth muscle cells in mice.

    PubMed

    Gong, Yan-Chun; He, Yue; Wang, Hao; Niu, Wen-Quan; Ji, Kai-Da; Li, Hua

    2016-09-01

    The process of vascular calcification shares numerous similarities with that of skeletal mineralization and involves the deposition of hydroxyapatite crystals in arteries and cardiac valves. However, the underlying cellular mechanism remains to be fully elucidated. Microarray analysis in the present study demonstrated that greater than 2,000 genes were upregulated during the calcification of murine vascular smooth muscle cells (VSMCs), of which osterix (OSX) and integrin‑binding sialoprotein (IBSP) were the most significantly differentially expressed genes. Following the validation of increased OSX and IBSP expression by reverse transcription‑quantitative polymerase chain reaction in calcifying murine VSMCs induced by aldosterone. Subsequent to transfection with siRNA‑OSX, results indicated that OSX may inhibit calcification of VSMCs via IBSP. It was suggested that the increased OSX expression in calcifying VSMCs may reflect the well‑established prenatal role of OSX. A full understanding of the importance of OSX in this pathological process would improve understanding of the pathogenesis of vascular calcification.

  7. Irradiation-Induced Regulation of Plasminogen Activator Inhibitor Type-1 and Vascular Endothelial Growth Factor in Six Human Squamous Cell Carcinoma Lines of the Head and Neck

    SciTech Connect

    Artman, Tuuli; Schilling, Daniela; Multhoff, Gabriele

    2010-02-01

    Purpose: It has been shown that plasminogen activator inhibitor type-1 (PAI-1) and vascular endothelial growth factor (VEGF) are involved in neo-angiogenesis. The aim of this study was to investigate the irradiation-induced regulation of PAI-1 and VEGF in squamous cell carcinomas of the head and neck (SCCHN) cell lines of varying radiation sensitivity. Methods and Materials: Six cell lines derived from SCCHN were investigated in vitro. The colorimetric AlamarBlue assay was used to detect metabolic activity of cell lines during irradiation as a surrogate marker for radiation sensitivity. PAI-1 and VEGF secretion levels were measured by enzyme-linked immunosorbent assay 24, 48, and 72 h after irradiation with 0, 2, 6, and 10 Gy. The direct radioprotective effect of exogenous PAI-1 was measured using the clonogenic assay. For regulation studies, transforming growth factor-beta1 (TGF-beta1), hypoxia-inducible factor-1alpha (HIF-1alpha), hypoxia-inducible factor-2alpha (HIF-2alpha), or both HIF-1alpha and HIF-2alpha were downregulated using siRNA. Results: Although baseline levels varied greatly, irradiation led to a comparable dose-dependent increase in PAI-1 and VEGF secretion in all six cell lines. Addition of exogenous stable PAI-1 to the low PAI-1-expressing cell lines, XF354 and FaDu, did not lead to a radioprotective effect. Downregulation of TGF-beta1 significantly decreased VEGF secretion in radiation-sensitive XF354 cells, and downregulation of HIF-1alpha and HIF-2alpha reduced PAI-1 and VEGF secretion in radiation-resistant SAS cells. Conclusions: Irradiation dose-dependently increased PAI-1 and VEGF secretion in all SCCHN cell lines tested regardless of their basal levels and radiation sensitivity. In addition, TGF-beta1 and HIF-1alpha could be partly responsible for VEGF and PAI-1 upregulation after irradiation.

  8. Catechins inhibit angiotensin II-induced vascular smooth muscle cell proliferation via mitogen-activated protein kinase pathway.

    PubMed

    Won, Sun-Mi; Park, Youn-Hee; Kim, Hee-Jung; Park, Kwon-Moo; Lee, Won-Jung

    2006-10-31

    Catechins, components of green tea, reduce the incidence of cardiovascular diseases such as atherosclerosis. Angiotensin II (Ang II) is highly implicated in the proliferation of vascular smooth muscle cells (VSMC), resulting in atherosclerosis. The acting mechanisms of the catechins remain to be defined in the proliferation of VSMC induced by Ang II. Here we report that catechin, epicatechin (EC), epicatechingallate (ECG) or epigallocatechingallate (EGCG) significantly inhibits the Ang II-induced [3H]thymidine incorporation into the primary cultured rat aortic VSMC. Ang II increases the phosphorylation of the extracellular signal-regulated protein kinase 1/2 (ERK 1/2), c-jun-N-terminal kinase 1/2 (JNK 1/2), or p38 mitogen-activated protein kinases (MAPKs) and mRNA expression of c-jun and c-fos. The EGCG pretreatment inhibits the Ang II-induced phosphorylation of ERK 1/2, JNK 1/2, or p38 MAPK, and the expression of c-jun or c-fos mRNA. U0126, a MEK inhibitor, SP600125, a JNK inhibitor, or SB203580, a p38 inhibitor, attenuates the Ang II-induced [3H]thymidine incorporation into the VSMC. In conclusion, catechins inhibit the Ang II-stimulated VSMC proliferation via the inhibition of the Ang II-stimulated activation of MAPK and activator protein-1 signaling pathways. The antiproliferative effect of catechins may be associated with the reduced risk of cardiovascular diseases by the intake of green tea. Catechins may be useful in the development of prevention and therapeutics of vascular diseases.

  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. c-Ski inhibits autophagy of vascular smooth muscle cells induced by oxLDL and PDGF.

    PubMed

    Li, Jun; Zhao, Li; Yang, Ting; Zeng, Yi-Jun; Yang, Kang

    2014-01-01

    Autophagy is increasingly being recognized as a critical determinant of vascular smooth muscle cell (VSMC) biology. Previously, we have demonstrated that c-Ski inhibits VSMC proliferation stimulated by transforming growth factor β (TGF-β), but it is not clear whether c-Ski has the similar protective role against other vascular injury factors and whether regulation of autophagy is involved in its protective effects on VSMC. Accordingly, in this study, rat aortic A10 VSMCs were treated with 40 µg/ml oxidized low-density lipoprotein (oxLDL) or 20 ng/ml platelet-derived growth factor (PDGF), both of which were autophagy inducers and closely related to the abnormal proliferation of VSMCs. Overexpression of c-Ski in A10 cells significantly suppressed the oxLDL- and PDGF- induced autophagy. This action of c-Ski resulted in inhibiting the cell proliferation, the decrease of contractile phenotype marker α-SMA expression while the increase of synthetic phenotype marker osteopontin expression stimulated by oxLDL or PDGF. Inversely, knockdown of c-Ski by RNAi enhanced the stimulatory effects of oxLDL or PDGF on A10 cell growth and phenotype transition. And further investigation found that inhibition of AKT phosphorylation to downregulate proliferating cell nuclear antigen (PCNA) expression, was involved in the regulation of autophagy and associated functions by c-Ski in the oxLDL- and PDGF-stimulated VSMCs. Collectively, c-Ski may play an important role in inhibiting autophagy to protect VSMCs against some harsh stress including oxLDL and PDGF.

  11. (2S)-naringenin from Typha angustata inhibits vascular smooth muscle cell proliferation via a G0/G1 arrest.

    PubMed

    Lee, Jung-Jin; Yi, Hyoseok; Kim, In-Su; Kim, Yohan; Nhiem, Nguyen Xuan; Kim, Young Ho; Myung, Chang-Seon

    2012-02-15

    Typha angustata is used in traditional Chinese medicine for a variety of clinical disorders. Its pharmacological actions include beneficial effects on hyperlipidemia and myocardial infarction, as well as labor-inducing and antibacterial effects. We investigated the mechanism underlying the ability of (2S)-naringenin, an active compound from Typha angustata, to inhibit the proliferation of vascular smooth muscle cells (VSMCs). After measuring the antiproliferative effect of (2S)-naringenin on VSMC proliferation using cell proliferation and viability assays, the possible involvement of a signaling pathway associated with platelet-derived growth factor receptor β (PDGF-Rβ), extracellular signal regulated kinase 1/2 (ERK1/2), phosphatidylinositol 3-kinase (PI3K)-linked protein kinase B (Akt/PKB), or phospholipase C-γ1 (PLCγ1) was investigated by immunoblotting. Moreover, the effect of (2S)-naringenin on DNA synthesis and the cell cycle was examined using a [(3)H]-thymidine incorporation assay and flow cytometry. (2S)-Naringenin significantly inhibited PDGF-BB-induced VSMC proliferation in a concentration-dependent manner, but did not affect signaling pathways associated with PDGF-Rβ, Akt/PKB, ERK1/2, or PLCγ1. However, (2S)-naringenin suppressed DNA synthesis via a G(0)/G(1) cell cycle arrest. Accordingly, the expression of cyclins D1 and E and cyclin-dependent kinases 2 and 4 was inhibited in a concentration-dependent manner; moreover, the phosphorylation of retinoblastoma protein was suppressed. Our results show that (2S)-naringenin inhibited the PDGF-BB-induced proliferation of VSMCs via a G(0)/G(1) arrest; thus, (2S)-naringenin may be valuable as a therapeutic agent for managing atherosclerosis and/or vascular restenosis. Crown Copyright © 2011. Published by Elsevier Ireland Ltd. All rights reserved.

  12. Magnesium inhibits Wnt/β-catenin activity and reverses the osteogenic transformation of vascular smooth muscle cells.

    PubMed

    Montes de Oca, Addy; Guerrero, Fatima; Martinez-Moreno, Julio M; Madueño, Juan A; Herencia, Carmen; Peralta, Alan; Almaden, Yolanda; Lopez, Ignacio; Aguilera-Tejero, Escolastico; Gundlach, Kristina; Büchel, Janine; Peter, Mirjam E; Passlick-Deetjen, Jutta; Rodriguez, Mariano; Muñoz-Castañeda, Juan R

    2014-01-01

    Magnesium reduces vascular smooth muscle cell (VSMC) calcification in vitro but the mechanism has not been revealed so far. This work used only slightly increased magnesium levels and aimed at determining: a) whether inhibition of magnesium transport into the cell influences VSMC calcification, b) whether Wnt/β-catenin signaling, a key mediator of osteogenic differentiation, is modified by magnesium and c) whether magnesium can influence already established vascular calcification. Human VSMC incubated with high phosphate (3.3 mM) and moderately elevated magnesium (1.4 mM) significantly reduced VSMC calcification and expression of the osteogenic transcription factors Cbfa-1 and osterix, and up-regulated expression of the natural calcification inhibitors matrix Gla protein (MGP) and osteoprotegerin (OPG). The protective effects of magnesium on calcification and expression of osteogenic markers were no longer observed in VSMC cultured with an inhibitor of cellular magnesium transport (2-aminoethoxy-diphenylborate [2-APB]). High phosphate induced activation of Wnt/β-catenin pathway as demonstrated by the translocation of β-catenin into the nucleus, increased expression of the frizzled-3 gene, and downregulation of Dkk-1 gene, a specific antagonist of the Wnt/β-catenin signaling pathway. The addition of magnesium however inhibited phosphate-induced activation of Wnt/β-catenin signaling pathway. Furthermore, TRPM7 silencing using siRNA resulted in activation of Wnt/β-catenin signaling pathway. Additional experiments were performed to test the ability of magnesium to halt the progression of already established VSMC calcification in vitro. The delayed addition of magnesium decreased calcium content, down-regulated Cbfa-1 and osterix and up-regulated MGP and OPG, when compared with a control group. This effect was not observed when 2-APB was added. In conclusion, magnesium transport through the cell membrane is important to inhibit VSMC calcification in vitro

  13. 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.

  14. Nitrogen Can Alleviate the Inhibition of Photosynthesis Caused by High Temperature Stress under Both Steady-State and Flecked Irradiance.

    PubMed

    Huang, Guanjun; Zhang, Qiangqiang; Wei, Xinghai; Peng, Shaobing; Li, Yong

    2017-01-01

    Nitrogen is one of the most important elements for plants and is closely related to photosynthesis. High temperature stress significantly inhibits photosynthesis under both steady-state and flecked irradiance. However, it is not known whether nitrogen can affect the decrease in photosynthesis caused by high temperature, especially under flecked irradiance. In the present study, a pot experiment was conducted under two nitrogen (N) supplies with rice plants, and the steady-state and dynamic photosynthesis rates were measured under 28 and 40°C. High temperature significantly increased leaf hydraulic conductance (Kleaf) under high N supply (HN) but not under low N supply (LN). The increased Kleaf maintained a constant leaf water potential (Ψleaf) and steady-state stomatal conductance (gs,sat) under HN, while the Ψleaf and gs,sat significantly decreased under high temperature in LN conditions. This resulted in a more severe decrease in steady-state photosynthesis (Asat) under high temperature in the LN conditions. After shifting from low to high light, high temperature significantly delayed the recovery of photosynthesis, which resulted in more carbon loss under flecked irradiance. These effects were obtained under HN to a lesser extent than under LN supply. Therefore, it is concluded that nitrogen can alleviate the inhibition of photosynthesis caused by high temperature stress under both steady-state and flecked irradiance.

  15. Nitrogen Can Alleviate the Inhibition of Photosynthesis Caused by High Temperature Stress under Both Steady-State and Flecked Irradiance

    PubMed Central

    Huang, Guanjun; Zhang, Qiangqiang; Wei, Xinghai; Peng, Shaobing; Li, Yong

    2017-01-01

    Nitrogen is one of the most important elements for plants and is closely related to photosynthesis. High temperature stress significantly inhibits photosynthesis under both steady-state and flecked irradiance. However, it is not known whether nitrogen can affect the decrease in photosynthesis caused by high temperature, especially under flecked irradiance. In the present study, a pot experiment was conducted under two nitrogen (N) supplies with rice plants, and the steady-state and dynamic photosynthesis rates were measured under 28 and 40°C. High temperature significantly increased leaf hydraulic conductance (Kleaf) under high N supply (HN) but not under low N supply (LN). The increased Kleaf maintained a constant leaf water potential (Ψleaf) and steady-state stomatal conductance (gs,sat) under HN, while the Ψleaf and gs,sat significantly decreased under high temperature in LN conditions. This resulted in a more severe decrease in steady-state photosynthesis (Asat) under high temperature in the LN conditions. After shifting from low to high light, high temperature significantly delayed the recovery of photosynthesis, which resulted in more carbon loss under flecked irradiance. These effects were obtained under HN to a lesser extent than under LN supply. Therefore, it is concluded that nitrogen can alleviate the inhibition of photosynthesis caused by high temperature stress under both steady-state and flecked irradiance. PMID:28634485

  16. 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.

  17. Ultraviolet irradiation increases the sensitivity of cultured human skin cells to cadmium probably through the inhibition of metallothionein gene expression.

    PubMed

    Yamada, Hirotomo; Murata, Mie; Suzuki, Kaoru; Koizumi, Shinji

    2004-11-01

    We previously developed an apparatus that can irradiate cultured cells with monochromatic ultraviolet (UV) rays to exactly assess the biological effects of UV components on mammalian cells. Using this device, we studied the effects of UV in and near the UVB region on the general as well as specific protein synthesis of the human skin-derived NB1RGB cells. We found that Cd-induced synthesis of metallothioneins (MTs), which are the proteins involved in the protection against heavy metals and oxidative stress, is inhibited by UV at 280 nm more extensively than total protein synthesis. Such an inhibition was observed when MTs were induced by different inducers such as Cd, Zn, and dexamethasone in three human cell lines, indicating that it is not an event specific to a certain inducer or a certain cell type. By contrast, UV at 300 or 320 nm showed only a marginal effect. UV at 280 nm was likely to block MT gene transcription because Cd-induced increase of MT mRNA was strongly inhibited by irradiation. Cd induction of 70-kDa heat shock protein mRNA was also inhibited by UV irradiation, suggesting that the expression of inducible genes are commonly sensitive to UV. Furthermore, we observed that the irradiation of UV at 280 nm renders NB1RGB cells extremely susceptible to Cd, probably due to the reduced MT synthesis. These observations strongly suggest that UV at 280 nm severely damages cellular inducible protective functions, warning us of a new risk of UV exposure.

  18. 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.

  19. Camptothecin inhibits platelet-derived growth factor-BB-induced proliferation of rat aortic vascular smooth muscle cells through inhibition of PI3K/Akt signaling pathway

    SciTech Connect

    Park, Eun-Seok; Kang, Shin-il; Yoo, Kyu-dong; Lee, Mi-Yea; Yoo, Hwan-Soo; Hong, Jin-Tae; Shin, Hwa-Sup; Kim, Bokyung; Yun, Yeo-Pyo

    2013-04-15

    The abnormal proliferation of vascular smooth muscle cells (VSMCs) in arterial wall is a major cause of vascular disorders such as atherosclerosis and restenosis after angioplasty. In this study, we investigated not only the inhibitory effects of camptothecin (CPT) on PDGF-BB-induced VSMC proliferation, but also its molecular mechanism of this inhibition. CPT significantly inhibited proliferation with IC50 value of 0.58 μM and the DNA synthesis of PDGF-BB-stimulated VSMCs in a dose-dependent manner (0.5–2 μM ) without any cytotoxicity. CPT induced the cell cycle arrest at G0/G1 phase. Also, CPT decreased the expressions of G0/G1-specific regulatory proteins including cyclin-dependent kinase (CDK)2, cyclin D1 and PCNA in PDGF-BB-stimulated VSMCs. Pre-incubation of VSMCs with CPT significantly inhibited PDGF-BB-induced Akt activation, whereas CPT did not affect PDGF-receptor beta phosphorylation, extracellular signal-regulated kinase (ERK) 1/2 phosphorylation and phospholipase C (PLC)-γ1 phosphorylation in PDGF-BB signaling pathway. Our data showed that CPT pre-treatment inhibited VSMC proliferation, and that the inhibitory effect of CPT was enhanced by LY294002, a PI3K inhibitor, on PDGF-BB-induced VSMC proliferation. In addition, inhibiting the PI3K/Akt pathway by LY294002 significantly enhanced the suppression of PCNA expression and Akt activation by CPT. These results suggest that the anti-proliferative activity of CPT is mediated in part by downregulating the PI3K/Akt signaling pathway. - Highlights: ► CPT inhibits proliferation of PDGF-BB-induced VSMC without cytotoxicity. ► CPT arrests the cell cycle in G0/G1 phase by downregulation of cyclin D1 and CDK2. ► CPT significantly attenuates Akt phosphorylation in PDGF-BB signaling pathway. ► LY294002 enhanced the inhibitory effect of CPT on VSMC proliferation. ► Thus, CPT is mediated by downregulating the PI3K/Akt signaling pathway.

  20. Inhibition of Autophagy Enhances Curcumin United light irradiation-induced Oxidative Stress and Tumor Growth Suppression in Human Melanoma Cells

    PubMed Central

    Niu, Tianhui; Tian, Yan; Mei, Zhusong; Guo, Guangjin

    2016-01-01

    Malignant melanoma is the most aggressive form of skin carcinoma, which possesses fast propagating and highly invasive characteristics. Curcumin is a natural phenol compound that has various biological activities, such as anti-proliferative and apoptosis-accelerating impacts on tumor cells. Unfortunately, the therapeutical activities of Cur are severely hindered due to its extremely low bioavailability. In this study, a cooperative therapy of low concentration Cur combined with red united blue light irradiation was performed to inspect the synergistic effects on the apoptosis, proliferation and autophagy in human melanoma A375 cell. The results showed that red united blue light irradiation efficaciously synergized with Cur to trigger oxidative stress-mediated cell death, induce apoptosis and inhibit cell proliferation. Meanwhile, Western blotting revealed that combined disposure induced the formation of autophagosomes. Conversely, inhibition of the autophagy enhanced apoptosis, obstructed cell cycle arrest and induced reversible proliferation arrest to senescence. These findings suggest that Cur combined with red united blue light irradiation could generate photochemo-preventive effects via enhancing apoptosis and triggering autophagy, and pharmacological inhibition of autophagy convert reversible arrested cells to senescence, therefore reducing the possibility that damaged cells might escape programmed death. PMID:27502897

  1. Cannabinoid CB{sub 1} receptor inhibition decreases vascular smooth muscle migration and proliferation

    SciTech Connect

    Rajesh, Mohanraj; Mukhopadhyay, Partha; Hasko, Gyoergy; Pacher, Pal

    2008-12-26

    Vascular smooth muscle proliferation and migration triggered by inflammatory stimuli and chemoattractants such as platelet-derived growth factor (PDGF) are key events in the development and progression of atherosclerosis and restenosis. Cannabinoids may modulate cell proliferation and migration in various cell types through cannabinoid receptors. Here we investigated the effects of CB{sub 1} receptor antagonist rimonabant (SR141716A), which has recently been shown to have anti-atherosclerotic effects both in mice and humans, on PDGF-induced proliferation, migration, and signal transduction of human coronary artery smooth muscle cells (HCASMCs). PDGF induced Ras and ERK 1/2 activation, while increasing proliferation and migration of HCASMCs, which were dose dependently attenuated by CB{sub 1} antagonist, rimonabant. These findings suggest that in addition to improving plasma lipid alterations and decreasing inflammatory cell migration and inflammatory response, CB{sub 1} antagonists may exert beneficial effects in atherosclerosis and restenosis by decreasing vascular smooth muscle proliferation and migration.

  2. Internal resistance in winter oilseed rape inhibits systemic spread of the vascular pathogen Verticillium longisporum.

    PubMed

    Eynck, C; Koopmann, B; Karlovsky, P; von Tiedemann, A

    2009-07-01

    Verticillium longisporum is a vascular fungal pathogen presently threatening oilseed rape production in Europe. Systemic spread and vascular responses were studied in a susceptible ('Falcon') and a resistant genotype (SEM 05-500256) of Brassica napus. Colonization of both genotypes after dip-inoculation of the roots followed by quantitative polymerase chain reaction revealed similarities only in the initial stages of root penetration and colonization of the hypocotyl, while a substantial invasion of the shoot was only recorded in 'Falcon'. It is concluded that the type of resistance represented in SEM 05-500256 does not prevent the plant base from being invaded as it is internally expressed well after root penetration and colonization of the plant base. The morphological and biochemical nature of barriers induced in the hypocotyl tissue upon infection was studied with histochemical methods accompanied by biochemical analyses. Histochemical studies revealed the build-up of vascular occlusions and the reinforcement of tracheary elements through the deposition of cell wall-bound phenolics and lignin. Furthermore, the accumulation of soluble phenolics was observed. Although these responses were found in vascular tissues of both genotypes, they occurred with a significantly higher intensity in the resistant genotype and corresponded with the disease phenotype. In the resistant genotype phenols were differentially expressed in a time-dependent manner with preformed soluble and cell wall-bound phenolics at earlier time points and de novo formation of lignin and lignin-like polymers at later stages of infection. This is the first study identifying a crucial role of phenol metabolism in internal defense of B. napus against V. longisporum and locating the crucial defense responses in the plant hypocotyl.

  3. 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.

  4. 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.

  5. 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.

  6. Sesamin Inhibits PDGF-Mediated Proliferation of Vascular Smooth Muscle Cells by Upregulating p21 and p27.

    PubMed

    Han, Joo-Hui; Lee, Sang-Gil; Jung, Sang-Hyuk; Lee, Jung-Jin; Park, Hyun-Soo; Kim, Young Ho; Myung, Chang-Seon

    2015-08-26

    Sesamin, an active ingredient of Asiasarum heterotropoides, is known to exhibit many bioactive functions, but the effect thereof on vascular smooth muscle cell (VSMC) proliferation remains poorly understood. Hence, we explored the antiproliferative action of sesamin on VSMCs and the underlying mechanism thereof, focusing on possible effects of sesamin on cell cycle progression. Sesamin significantly inhibited platelet-derived growth factor (PDGF)-induced VSMC proliferation (inhibition percentage at 1, 5, and 10 μM sesamin was 49.8 ± 22.0%, 74.6 ± 19.9%, and 87.8 ± 13.0%, respectively) in the absence of cytotoxicity and apoptosis, and PDGF-induced DNA synthesis; and arrested cell cycle progression in the G0/G1-to-S phase. Sesamin potently inhibited cyclin D1 and CDK4 expression, pRb phosphorylation, and expression of the proliferating cell nuclear antigen (PCNA); and upregulated p27(KIP1), p21(CIP1), and p53. The results thus indicate that the antiproliferative effect of sesamin on PDGF-stimulated VSMCs is attributable to arrest of the cell cycle in G0/G1 caused, in turn, by upregulation of p27(KIP1), p21(CIP1), and p53, and inhibition of cyclin E-CDK2 and cyclin D1-CDK4 expression.

  7. Reversible inhibition of cellular respiration by nitric oxide in vascular inflammation.

    PubMed

    Borutaite, V; Matthias, A; Harris, H; Moncada, S; Brown, G C

    2001-12-01

    Incubation of rat aortas with endotoxin and interferon-gamma for 24 h resulted in an aortic oxygen consumption that was substantially inhibited and strongly oxygen dependent (37% inhibition at 160 microM O(2) and 62% inhibition at 80 microM O(2) relative to untreated aortas). This respiratory inhibition was reversed by a nitric oxide (NO) scavenger (oxyhemoglobin) or by an inhibitor of inducible NO synthase [N-(3-(aminomethyl)benzyl)acetamide x 2HCl, 1400W], but not by an inhibitor of soluble guanylate cyclase (1H-[1,2,4]oxadiazolo[4,3-a]-quinoxalin-1-one). Addition of 1 microM NO to untreated aortas caused rapid and reversible inhibition of oxygen consumption that was greater at lower oxygen concentrations. Incubation of endothelial cells isolated from rat aortas with endotoxin and interferon-gamma for 24 h resulted in a steady-state NO concentration of approximately 0.5 microM and 90% inhibition of cellular oxygen consumption that was immediately reversed by an NO scavenger (oxyhemoglobin). These results suggest that during inflammation and sepsis, tissue respiration may be substantially reduced due to inhibition by NO of cytochrome oxidase.

  8. Relations between the physiological state of onions and an effective sprout inhibition by irradiation

    NASA Astrophysics Data System (ADS)

    Dahlhelm, H.; Matejko, C.

    The mitotic activity in shoot meristem was examined during the entire storage period of onions ( Allium cepa L.) and was compared with the growth of the inner bud of the bulbs unirradiated and after irradiation. The meaning of cell division at the shoot apex for the sprouting of onions and the effect of γ-irradiation are discussed.

  9. Vitisin B, a resveratrol tetramer, inhibits migration through inhibition of PDGF signaling and enhancement of cell adhesiveness in cultured vascular smooth muscle cells

    SciTech Connect

    Ong, Eng-Thaim; Hwang, Tsong-Long; Huang, Yu-Ling; Lin, Chwan-Fwu; Wu, Wen-Bin

    2011-10-15

    Vascular smooth muscle cells (VSMCs) play an important role in normal vessel formation and in the development and progression of cardiovascular diseases. Grape plants contain resveratrol monomer and oligomers and drinking of wine made from grape has been linked to 'French Paradox'. In this study we evaluated the effect of vitisin B, a resveratrol tetramer, on VSMC behaviors. Vitisin B inhibited basal and PDGF-induced VSMC migration. Strikingly, it did not inhibit VSMC proliferation but inversely enhanced cell cycle progression and proliferation. Among the tested resveratrol oligomers, vitisin B showed an excellent inhibitory activity and selectivity on PDGF signaling. The anti-migratory effect by vitisin B was due to direct inhibition on PDGF signaling but was independent of interference with PDGF binding to VSMCs. Moreover, the enhanced VSMC adhesiveness to matrix contributed to the anti-migratory effect by vitisin B. Fluorescence microscopy revealed an enhanced reorganization of actin cytoskeleton and redistribution of activated focal adhesion proteins from cytosol to the peripheral edge of the cell membrane. This was confirmed by the observation that enhanced adhesiveness was repressed by the Src inhibitor. Finally, among the effects elicited by vitisin B, only the inhibitory effect toward basal migration was partially through estrogen receptor activation. We have demonstrated here that a resveratrol tetramer exhibited dual but opposite actions on VSMCs, one is to inhibit VSMC migration and the other is to promote VSMC proliferation. The anti-migratory effect was through a potent inhibition on PDGF signaling and novel enhancement on cell adhesion. - Highlights: > Several resveratrol oligomers from grape plants are examined on VSMC behaviors. > Tetraoligomer vitisin B shows excellent inhibitory activity and selectivity. > It exerts dual but opposing actions: anti-migratory and pro-proliferative effects. > The anti-migratory effect results from anti-PDGF signaling

  10. Metabolic and vascular actions of endothelin-1 are inhibited by insulin-mediated vasodilation in perfused rat hindlimb muscle.

    PubMed

    Kolka, Cathryn M; Rattigan, Stephen; Richards, Stephen; Clark, Michael G

    2005-08-01

    Endothelin-1 (ET-1) is a potent endothelium-derived vasoactive peptide and may be involved in the microvascular actions of insulin for the normal delivery of nutrients to muscle, although higher levels may be antagonistic. Our aim was to observe the interaction between ET-1 and insulin. Initially, we attempted to distinguish the vascular from the metabolic effects of ET-1 in the constant-flow pump-perfused rat hindlimb by using various doses of ET-1 and measuring changes in perfusion pressure (PP), oxygen consumption (VO(2)), glucose uptake (GU) and lactate release (LR). Sodium nitroprusside (SNP) was used to block vasoconstriction and to thus assess the relationship between vascular and metabolic effects. Insulin was included in later experiments to determine the interaction between insulin and ET-1 on the above parameters. ET-1 caused a dose-dependent increase in PP. Effects on VO(2) were biphasic, with low doses increasing VO(2), and higher doses leading to a net inhibition. GU and LR were increased at lower doses (ET-1 < or =1 nM), but this effect was lost at higher doses (> or =10 nM ET-1). SNP (50 microM) fully blocked the increase in pressure and metabolism due to low-dose ET-1 and partly blocked both pressure and metabolic responses by the high dose. ET-1 vasodilatory activity was minimal at high or low dose. Insulin (15 nM) alone caused GU, which was not affected by ET-1. Of the other parameters measured, insulin behaved essentially the same as SNP, inhibiting the pressure and oxygen effects. Overall, these results show that ET-1 has a biphasic dose-dependent vasoconstrictor effect on hindlimb blood vessels, able to modulate flow to cause both the stimulation and inhibition of metabolism, although these effects are blocked by insulin, which is able to vasodilate against both low and high doses of ET-1.

  11. 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

  12. Exogenous H2S modulates mitochondrial fusion-fission to inhibit vascular smooth muscle cell proliferation in a hyperglycemic state.

    PubMed

    Sun, Aili; Wang, Yan; Liu, Jiaqi; Yu, Xiangjing; Sun, Yu; Yang, Fan; Dong, Shiyun; Wu, Jichao; Zhao, Yajun; Xu, Changqing; Lu, Fanghao; Zhang, Weihua

    2016-01-01

    Vascular smooth muscle cell (VSMC) proliferation in response to hyperglycemia is an important process in the development of arterial vessel hyperplasia. The shape change of mitochondria is dynamic and closely related to fission and fusion. Hydrogen sulfide (H2S) was confirmed to have anti-oxidative, anti-inflammatory and anti-proliferative effects. However, little it is known about its effects on mitochondrial morphology induced by hyperglycemia. The aim of the study is to demonstrate that H2S inhibits VSMC proliferation through regulating mitochondrial fission. We observe lower H2S levels as well as higher proliferative protein expression levels for proliferative cell nuclear antigen (PCNA) and cyclin D1 and higher mitochondrial fusion-fission protein expression levels for dynamin-related protein 1 (Drp 1) in human kidney arteries and in db/db mouse aorta. Exogenous H2S (100 μM NaHS) inhibits vascular smooth muscle cells of human pulmonary aorta(HPASMC) proliferation and migration in response to high glucose using the BrdU and scratch wound repair assays, decreases proliferative protein (PCNA and cyclin D1) expression, and reduces ROS production in the cytoplasm and mitochondria. When HPASMCs proliferate with a high glucose treatment, the mitochondria become small spheres with a short rod-shaped structure, whereas NaHS, a mitochondrial division inhibitor and siDrp prevent VSMC proliferation and maintain mitochondria as stationary and randomly dispersed with fixed structures. Exogenous H2S aids in inhibiting mitochondrial fragmentation and affects proliferation in db/db mice and HPASMCs by decreasing Drp 1 expression.

  13. Copper Chelation by Tetrathiomolybdate Inhibits Vascular Inflammation and Atherosclerotic Lesion Development in Apolipoprotein E-deficient Mice

    PubMed Central

    Wei, Hao; Zhang, Wei-Jian; Mcmillen, Timothy S.; Leboeuf, Renee C.; Frei, Balz

    2012-01-01

    Endothelial activation, which is characterized by upregulation of cellular adhesion molecules and pro-inflammatory chemokines and cytokines, and consequent monocyte recruitment to the arterial intima are etiologic factors in atherosclerosis. Redox-active transition metal ions, such as copper and iron, may play an important role in endothelial activation by stimulating redox-sensitive cell signaling pathways. We have shown previously that copper chelation by tetrathiomolybdate (TTM) inhibits LPS-induced acute inflammatory responses in vivo. Here, we investigated whether TTM can inhibit atherosclerotic lesion development in apolipoprotein E-deficient (apoE−/−) mice. We found that 10-week treatment of apoE−/− mice with TTM (33–66 ppm in the diet) reduced serum levels of the copper-containing protein, ceruloplasmin, by 47%, and serum iron by 26%. Tissue levels of “bioavailable” copper, assessed by the copper-to-molybdenum ratio, decreased by 80% in aorta and heart, whereas iron levels of these tissues were not affected by TTM treatment. Furthermore, TTM significantly attenuated atherosclerotic lesion development in whole aorta by 25% and descending aorta by 45% compared to non-TTM treated apoE−/− mice. This anti-atherogenic effect of TTM was accompanied by several anti-inflammatory effects, i.e., significantly decreased serum levels of soluble vascular cell and intercellular adhesion molecules (VCAM-1 and ICAM-1); reduced aortic gene expression of VCAM-1, ICAM-1, monocyte chemotactic protein-1, and pro-inflammatory cytokines; and significantly less aortic accumulation of M1 type macrophages. In contrast, serum levels of oxidized LDL were not reduced by TTM. These data indicate that TTM inhibits atherosclerosis in apoE−/− mice by reducing bioavailable copper and vascular inflammation, not by altering iron homeostasis or reducing oxidative stress. PMID:22770994

  14. CBP knockdown inhibits angiotensin II-induced vascular smooth muscle cells proliferation through downregulating NF-kB transcriptional activity.

    PubMed

    Yang, Jian; Jiang, Hong; Chen, Si-si; Chen, Jing; Xu, Sheng-kai; Li, Wan-qiang; Wang, Ji-chun

    2010-07-01

    CREB binding protein (CBP), a powerful transcriptional co-activator for various transcriptional factors, regulates cell behavior in many cell types. Angiotensin II (Ang II) contributes to vascular lesion by promoting vascular smooth muscle cells (VSMCs) proliferation and migration. Therefore, we examined whether CBP knockdown could suppress Ang II-induced VSMCs proliferation, and elucidated its underlying molecular mechanism. We constructed lentiviral vector expressing CBP-specific short hairpin RNAs (shRNAs) that efficiently silenced CBP. VSMCs proliferation was evaluated by bromodeoxyuridine (BrdU) incorporation assay. Protein and mRNA expression of CBP and relevant cytokines were examined by Western blot, ELISA, and real-time PCR, respectively. We also used luciferase reporter gene and electrophoretic mobility shift assay (EMSA) to detect Nuclear factor kappaB (NF-kB) transcriptional activity and DNA binding. Meanwhile, NF-kB p65 subunit nuclear translocation was confirmed by immunoblotting. Lentiviral-mediated CBP-shRNAs at different multiplicities of infection (MOI = 100, 150) both significantly suppressed Ang II-induced CBP expression. Knockdown of CBP markedly inhibited Ang II-stimulated VSMCs proliferation and cytokines (TNF-alpha and IL-6) production. However, this inhibitory effect was not enhanced at MOI of 150 compared with MOI of 100 (P > 0.05). CBP siRNA showed the potent inhibition on Ang II-induced NF-kB transcriptional activity. Similarly, no significant difference was found between CBP siRNA lentivirus treatment groups. Furthermore, CBP gene silencing had no effect on NF-kB nuclear translocation and DNA binding. These findings suggest that CBP knockdown inhibits Ang II-induced VSMCs proliferation and the mechanism is involved with downregulation of NF-kB transcriptional activity, not through reduction in NF-kB nuclear translocation or DNA binding. Maintaining proper CBP level may be a potential therapeutic target for Ang II-induced cardiovascular

  15. α-Iso-Cubebene Inhibits PDGF-Induced Vascular Smooth Muscle Cell Proliferation by Suppressing Osteopontin Expression.

    PubMed

    Jang, Min A; Lee, Seung Jin; Baek, Seung Eun; Park, So Youn; Choi, Young Whan; Kim, Chi Dae

    2017-01-01

    α-Iso-cubebene (ICB) is a dibenzocyclooctadiene lignin contained in Schisandra chinensis (SC), a well-known medicinal herb that ameliorates cardiovascular symptoms. Thus, we examined the effect of ICB on vascular smooth muscle cell (VSMC) proliferation, a key feature of diverse vascular diseases. When VSMCs primary cultured from rat thoracic aorta were stimulated with PDGF (1-10 ng/ml), cell proliferation and osteopontin (OPN) expression were concomitantly up-regulated, but these effects were attenuated when cells were treated with MPIIIB10, a neutralizing monoclonal antibody for OPN. In aortic tissues exposed to PDGF, sprouting VSMC numbers increased, which was attenuated in tissues from OPN-deficient mice. Furthermore, VSMC proliferation and OPN expression induced by PDGF were attenuated dose-dependently by ICB (10 or 30 μg/ml). Reporter assays conducted using OPN promoter-luciferase constructs showed that the promoter region 538-234 bp of the transcription start site was responsible for transcriptional activity enhancement by PDGF, which was significantly inhibited by ICB. Putative binding sites for AP-1 and C/EBPβ in the indicated promoter region were suggested by TF Search, and increased binding of AP-1 and C/EBPβ in PDGF-treated VSMCs was demonstrated using a ChIP assay. The increased bindings of AP-1 and C/EBPβ into OPN promoter were attenuated by ICB. Moreover, the PDGF-induced expression of OPN was markedly attenuated in VSMCs transfected with siRNA for AP-1 and C/EBPβ. These results indicate that ICB inhibit VSMC proliferation by inhibiting the AP-1 and C/EBPβ signaling pathways and thus downregulating OPN expression.

  16. α-Iso-Cubebene Inhibits PDGF-Induced Vascular Smooth Muscle Cell Proliferation by Suppressing Osteopontin Expression

    PubMed Central

    Jang, Min A.; Lee, Seung Jin; Baek, Seung Eun; Park, So Youn; Choi, Young Whan; Kim, Chi Dae

    2017-01-01

    α-Iso-cubebene (ICB) is a dibenzocyclooctadiene lignin contained in Schisandra chinensis (SC), a well-known medicinal herb that ameliorates cardiovascular symptoms. Thus, we examined the effect of ICB on vascular smooth muscle cell (VSMC) proliferation, a key feature of diverse vascular diseases. When VSMCs primary cultured from rat thoracic aorta were stimulated with PDGF (1–10 ng/ml), cell proliferation and osteopontin (OPN) expression were concomitantly up-regulated, but these effects were attenuated when cells were treated with MPIIIB10, a neutralizing monoclonal antibody for OPN. In aortic tissues exposed to PDGF, sprouting VSMC numbers increased, which was attenuated in tissues from OPN-deficient mice. Furthermore, VSMC proliferation and OPN expression induced by PDGF were attenuated dose-dependently by ICB (10 or 30 μg/ml). Reporter assays conducted using OPN promoter-luciferase constructs showed that the promoter region 538–234 bp of the transcription start site was responsible for transcriptional activity enhancement by PDGF, which was significantly inhibited by ICB. Putative binding sites for AP-1 and C/EBPβ in the indicated promoter region were suggested by TF Search, and increased binding of AP-1 and C/EBPβ in PDGF-treated VSMCs was demonstrated using a ChIP assay. The increased bindings of AP-1 and C/EBPβ into OPN promoter were attenuated by ICB. Moreover, the PDGF-induced expression of OPN was markedly attenuated in VSMCs transfected with siRNA for AP-1 and C/EBPβ. These results indicate that ICB inhibit VSMC proliferation by inhibiting the AP-1 and C/EBPβ signaling pathways and thus downregulating OPN expression. PMID:28114367

  17. 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.

  18. High-power helium-neon laser irradiation inhibits the growth of traumatic scars in vitro and in vivo.

    PubMed

    Shu, Bin; Ni, Guo-Xin; Zhang, Lian-Yang; Li, Xiang-Ping; Jiang, Wan-Ling; Zhang, Li-Qun

    2013-05-01

    This study explored the inhibitory effect of the high-power helium-neon (He-Ne) laser on the growth of scars post trauma. For the in vitro study, human wound fibroblasts were exposed to the high-power He-Ne laser for 30 min, once per day with different power densities (10, 50, 100, and 150 mW/cm(2)). After 3 days of repeated irradiation with the He-Ne laser, fibroblast proliferation and collagen synthesis were evaluated. For in vivo evaluation, a wounded animal model of hypertrophic scar formation was established. At postoperative day 21, the high-power He-Ne laser irradiation (output power 120 mW, 6 mm in diameter, 30 min each session, every other day) was performed on 20 scars. At postoperative day 35, the hydroxyproline content, apoptosis rate, PCNA protein expression and FADD mRNA level were assessed. The in vitro study showed that the irradiation group that received the power densities of 100 and 150 mW/cm(2) showed decreases in the cell proliferation index, increases in the percentage of cells in the G0/G1 phase, and decreases in collagen synthesis and type I procollagen gene expression. In the in vivo animal studies, regions exposed to He-Ne irradiation showed a significant decrease in scar thickness as well as decreases in hydroxyproline levels and PCNA protein expression. Results from the in vitro and in vivo studies suggest that repeated irradiation with a He-Ne laser at certain power densities inhibits fibroblast proliferation and collagen synthesis, thereby inhibits the growth of hypertrophic scars.

  19. 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.

  20. Discovery of novel sulfonated small molecules that inhibit vascular tube formation

    PubMed Central

    Raman, Karthik; Karuturi, Rajesh; Swarup, Vimal P.; Desai, Umesh R.; Kuberan, Balagurunathan

    2012-01-01

    Tumor-associated angiogenesis is a complex process that involves the interplay among several molecular players such as cell-surface heparan sulfate proteoglycans, vascular endothelial growth factors and their cognate receptors. PI-88, a highly sulfonated oligosaccharide, has been shown to have potent anti-angiogenic activity and is currently in clinical trials. However, one of the major drawbacks of large oligosaccharides such as PI-88 is that their synthesis often requires numerous complex synthetic steps. In this study, several novel polysulfonated small molecule carbohydrate mimetics, which can easily be synthesized in fewer steps, are identified as promising inhibitors of angiogenesis in an in vitro tube formation assay. PMID:22627041

  1. Effects of low-energy CO2 laser irradiation and the organic matrix on inhibition of enamel demineralization.

    PubMed

    Hsu, C Y; Jordan, T H; Dederich, D N; Wefel, J S

    2000-09-01

    In the past two decades, accumulated evidence has clearly demonstrated the inhibitory effects of laser irradiation on enamel demineralization, but the exact mechanisms of these effects remain unclear. The purpose of this study was to investigate the effects of low-energy CO2 laser irradiation on demineralization of both normal human enamel and human enamel with its organic matrix removed. Twenty-four human molars were collected, cleaned, and cut into two halves. One half of each tooth was randomly selected and its lipid and protein content extracted. The other half of each tooth was used as the matched control. Each tooth half had two window areas. All the left windows were treated with a low-energy laser irradiation, whereas the right windows served as the non-laser controls. After caries-like lesion formation in a pH-cycling environment, microradiographs of tooth sections were taken for quantification of demineralization. The mean mineral losses (with standard deviation) of the enamel control, the lased enamel, the non-organic enamel control, and the lased non-organic enamel subgroups were 3955 (1191), 52(49), 4565(1311), and 1191 (940), respectively. A factorial ANOVA showed significant effects of laser irradiation (p = 0.0001), organic matrix (p = 0.0125), and the laser-organic matrix interaction (p = 0.0377). The laser irradiation resulted in a greater than 98% reduction in mineral loss, but the laser effect dropped to about 70% when the organic matrix in the enamel was removed. The results suggest that clinically applicable CO2 laser irradiation may cause an almost complete inhibition of enamel demineralization.

  2. The flavonoid quercetin induces apoptosis and inhibits JNK activation in intimal vascular smooth muscle cells

    SciTech Connect

    Perez-Vizcaino, Francisco . E-mail: fperez@med.ucm.es; Bishop-Bailley, David; Lodi, Federica; Duarte, Juan; Cogolludo, Angel; Moreno, Laura; Bosca, Lisardo; Mitchell, Jane A.; Warner, Timothy D.

    2006-08-04

    Quercetin, the most abundant dietary flavonol, exerts vasodilator, anti-hypertensive, and anti-atherogenic effects and reduces the vascular remodelling associated with elevated blood pressure. Here, we have compared the effects of quercetin in intimal- and medial-type rat vascular smooth muscle cells (VSMC) in culture. After 48 h, quercetin reduced the viability of a polyclonal intimal-type cell line derived from neonatal aorta but not of a medial-type cell line derived from adult aorta. These differential effects were similar in both proliferating and quiescent VSMC. Quercetin also preferentially reduced the viability of intimal-type over medial-type VSMC in primary cultures derived from balloon-injured carotid arteries. The effects of quercetin on cell viability were mainly dependent upon induction of apoptosis, as demonstrated by nuclear condensation and fragmentation, and were unrelated to PPAR{gamma}, pro-oxidant effects or nitric oxide. The expression of MAPKs (ERK, p38, and JNK) and ERK phosphorylation were not different between intimal- and medial-type VSMC. p38 phosphorylation was negligible in both cell types. Medial-type showed a weak JNK phosphorylation while this was markedly increased in intimal-type cells. Quercetin reduced JNK phosphorylation but had no consistent effect on ERK phosphorylation. In conclusion, quercetin preferentially produced apoptosis in intimal-type compared to medial-type VSMC. This might play a role in the anti-atherogenic and anti-hypertensive effects of quercetin.

  3. The flavonoid quercetin induces apoptosis and inhibits JNK activation in intimal vascular smooth muscle cells.

    PubMed

    Perez-Vizcaino, Francisco; Bishop-Bailley, David; Lodi, Federica; Duarte, Juan; Cogolludo, Angel; Moreno, Laura; Bosca, Lisardo; Mitchell, Jane A; Warner, Timothy D

    2006-08-04

    Quercetin, the most abundant dietary flavonol, exerts vasodilator, anti-hypertensive, and anti-atherogenic effects and reduces the vascular remodelling associated with elevated blood pressure. Here, we have compared the effects of quercetin in intimal- and medial-type rat vascular smooth muscle cells (VSMC) in culture. After 48 h, quercetin reduced the viability of a polyclonal intimal-type cell line derived from neonatal aorta but not of a medial-type cell line derived from adult aorta. These differential effects were similar in both proliferating and quiescent VSMC. Quercetin also preferentially reduced the viability of intimal-type over medial-type VSMC in primary cultures derived from balloon-injured carotid arteries. The effects of quercetin on cell viability were mainly dependent upon induction of apoptosis, as demonstrated by nuclear condensation and fragmentation, and were unrelated to PPARgamma, pro-oxidant effects or nitric oxide. The expression of MAPKs (ERK, p38, and JNK) and ERK phosphorylation were not different between intimal- and medial-type VSMC. p38 phosphorylation was negligible in both cell types. Medial-type showed a weak JNK phosphorylation while this was markedly increased in intimal-type cells. Quercetin reduced JNK phosphorylation but had no consistent effect on ERK phosphorylation. In conclusion, quercetin preferentially produced apoptosis in intimal-type compared to medial-type VSMC. This might play a role in the anti-atherogenic and anti-hypertensive effects of quercetin.

  4. 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.

  5. Endogenous sulfur dioxide alleviates collagen remodeling via inhibiting TGF-β/Smad pathway in vascular smooth muscle cells.

    PubMed

    Huang, Yaqian; Shen, Zhizhou; Chen, Qinghua; Huang, Pan; Zhang, Heng; Du, Shuxu; Geng, Bin; Zhang, Chunyu; Li, Kun; Tang, Chaoshu; Du, Junbao; Jin, Hongfang

    2016-01-14

    The study was designed to investigate the role of endogenous sulfur dioxide (SO2) in collagen remodeling and its mechanisms in vascular smooth muscle cells (VSMCs). Overexpression of endogenous SO2 synthase aspartate aminotransferase (AAT) 1 or 2 increased SO2 levels and inhibited collagen I and III expressions induced by transforming growth factor (TGF)-β1 in VSMCs. In contrast, AAT1 or AAT2 knockdown induced a severe collagen deposition in TGF-β1-treated VSMCs. Furthermore, AAT1 or AAT2 overexpression suppressed procollagen I and III mRNA, upregulated matrix metalloproteinase (MMP)-13 expression, downregulated tissue inhibitors of MMP-1 level, and vice versa. Mechanistically, AAT1 or AAT2 overexpression inhibited phosphorylation of type I TGF-β receptor (TβRI) and Smad2/3 in TGF-β1-stimulated VSMCs. Whereas SB431542, an inhibitor of TGF-β1/Smad signaling pathway, attenuated excessive collagen deposition induced by AAT knockdown. Most importantly, ectopically expressing AAT or exogenous addition of 100 μM SO2 blocked AAT deficiency-aggravated collagen accumulation in TGF-β1-stimulatd VSMCs, while no inhibition was observed at 100 μM ethyl pyruvate. These findings indicated that endogenous SO2 alleviated collagen remodeling by controlling TGF-β1/TβRI/Smad2/3-mediated modulation of collagen synthesis and degradation.

  6. 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.

  7. 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

  8. 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.

  9. Cilostazol inhibits interleukin-1-induced ADAM17 expression through cAMP independent signaling in vascular smooth muscle cells.

    PubMed

    Takaguri, Akira; Morimoto, Mayumi; Imai, Shin-Ichi; Satoh, Kumi

    2016-03-01

    Increased A disintegrin and metalloprotease 17 (ADAM17) expression in vascular smooth muscle cells (VSMC) is implicated in the development of cardiovascular diseases including atherosclerosis and hypertension. Although cilostazol, type III phosphodiesterase (PDE III) inhibitor, has recently been found to inhibit VSMC proliferation, the mechanisms remain largely unclear. Here, we hypothesized that cilostazol regulates the ADAM17 expression in VSMC. In cultured VSMC, interleukin (IL)-1α and IL-1β significantly increased ADAM17 expression. MEK inhibitor U0126, NF-κB inhibitor BAY-11-7085, and siRNA targeting p65/RelA significantly inhibited IL-1α or IL-β-induced ADAM17 expression. Cilostazol significantly inhibited IL-1α or IL-1β-induced extracellular signal-regulated kinase (ERK) phosphorylation and ADAM17 expression. Unexpectedly, cilostamide, dibutryl cAMP, and forskolin did not affect IL-1-induced ADAM17 expression. Our results clearly demonstrated that IL-1 induces ADAM17 expression through ERK/NF-κB activation in VSMCs. Moreover, the inhibitory effects of cilostazol on IL-1-induced ADAM17 expression may be independent of the cAMP signaling pathway in VSMC. These novel findings may provide important clues to understanding the expression mechanisms of ADAM17 and the inhibitory mechanisms of cilostazol in VSMC proliferation. © 2015 International Federation for Cell Biology.

  10. Dehydroepiandrosterone (DHEA) Inhibition of Monocyte Binding by Vascular Endothelium Is Associated With Sialylation of Neural Cell Adhesion Molecule

    PubMed Central

    Curatola, Anna-Maria; Huang, Kui; Naftolin, Frederick

    2012-01-01

    Rationale: Adhesion of monocytes to vascular endothelium is necessary for atheroma formation. This adhesion requires binding of endothelial neural cell adhesion molecule (NCAM) to monocyte NCAM. NCAM:NCAM binding is blocked by sialylation of NCAM (polysialylated NCAM; PSA-NCAM). Since estradiol (E2) and dihydrotestosterone (DHT) induced PSA-NCAM and decreased monocyte adhesion, in consideration of possible clinical applications we tested whether their prohormone dehydroepiandrosterone (DHEA) has similar effects. Experimental: (1) DHEA was administered to cultured human coronary artery endothelial cells (HCAECs) from men and women. Monocyte binding was assessed using fluorescence-labeled monocytes. (2) HCEACs were incubated with E2, DHT, DHEA alone, or with trilostane, fulvestrant or flutamide. Expression of PSA-NCAM was assessed by immunohistochemistry and Western blotting. Results: Dehydroepiandrosterone inhibited monocyte adhesion to HCAECs by ≥50% (P < .01). Fulvestrant or flutamide blockade of DHEA’s inhibition of monocyte binding appeared to be gender dependent. The DHEA-induced expression of PSA-NCAM was completely blocked by trilostane. Conclusions: In these preliminary in vitro studies, DHEA increased PSA-NCAM expression and inhibited monocyte binding in an estrogen- and androgen receptor-dependent manner. Dehydroepiandrosteroneappears to act via its end metabolites, E2 and DHT. Dehydroepiandrosterone could furnish clinical prevention against atherogenesis and arteriosclerosis. PMID:22228741

  11. Dehydroepiandrosterone (DHEA) inhibition of monocyte binding by vascular endothelium is associated with sialylation of neural cell adhesion molecule.

    PubMed

    Curatola, Anna-Maria; Huang, Kui; Naftolin, Frederick

    2012-01-01

    Adhesion of monocytes to vascular endothelium is necessary for atheroma formation. This adhesion requires binding of endothelial neural cell adhesion molecule (NCAM) to monocyte NCAM. NCAM:NCAM binding is blocked by sialylation of NCAM (polysialylated NCAM; PSA-NCAM). Since estradiol (E2) and dihydrotestosterone (DHT) induced PSA-NCAM and decreased monocyte adhesion, in consideration of possible clinical applications we tested whether their prohormone dehydroepiandrosterone (DHEA) has similar effects. (1) DHEA was administered to cultured human coronary artery endothelial cells (HCAECs) from men and women. Monocyte binding was assessed using fluorescence-labeled monocytes. (2) HCEACs were incubated with E2, DHT, DHEA alone, or with trilostane, fulvestrant or flutamide. Expression of PSA-NCAM was assessed by immunohistochemistry and Western blotting. Dehydroepiandrosterone inhibited monocyte adhesion to HCAECs by ≥50% (P < .01). Fulvestrant or flutamide blockade of DHEA's inhibition of monocyte binding appeared to be gender dependent. The DHEA-induced expression of PSA-NCAM was completely blocked by trilostane. In these preliminary in vitro studies, DHEA increased PSA-NCAM expression and inhibited monocyte binding in an estrogen- and androgen receptor-dependent manner. Dehydroepiandrosteroneappears to act via its end metabolites, E2 and DHT. Dehydroepiandrosterone could furnish clinical prevention against atherogenesis and arteriosclerosis.

  12. Vasostatin-2 inhibits cell proliferation and adhesion in vascular smooth muscle cells, which are associated with the progression of atherosclerosis.

    PubMed

    Hou, Jianghong; Xue, Xiaolin; Li, Junnong

    2016-01-22

    Recently, the serum expression level of vasostatin-2 was found to be reduced and is being studied as an important indicator to assess the presence and severity of coronary artery disease; the functional properties of vasostatin-2 and its relationship with the development of atherosclerosis remains unclear. In this study, we attempted to detect the expression of vasostatin-2 and its impact on human vascular smooth muscle cells (VSMCs). Quantitative real-time PCR (qRT-PCR) and western blot were used to assess the expression level of vasostatin-2 in VSMCs between those from atherosclerosis and disease-free donors; we found that vasostatin-2 was significantly down-regulated in atherosclerosis patient tissues and cell lines. In addition, the over-expression of vasostatin-2 apparently inhibits cell proliferation and migration in VSMCs. Gain-of-function in vitro experiments further show that vasostatin-2 over-expression significantly inhibits inflammatory cytokines release in VSMCs. In addition, cell adhesion experimental analysis showed that soluble adhesion molecules (sICAM-1, sVCAM-1) had decreased expression when vasostatin-2 was over-expressed in VSMCs. Therefore, our results indicate that vasostatin-2 is an atherosclerosis-related factor that can inhibit cell proliferation, inflammatory response and cell adhesion in VSMCs. Taken together, our results indicate that vasostatin-2 could serve as a potential diagnostic biomarker and therapeutic option for human atherosclerosis in the near future.

  13. Quantification of rat retinal growth and vascular population changes after single and split doses of proton irradiation: translational study using stereology methods

    NASA Technical Reports Server (NTRS)

    Mao, Xiao W.; Archambeau, John O.; Kubinova, Lucie; Boyle, Soames; Petersen, Georgia; Grove, Roger; Nelson, G. A. (Principal Investigator)

    2003-01-01

    This study quantified architectural and population changes in the rat retinal vasculature after proton irradiation using stereology. A 100 MeV conformal proton beam delivered 8, 14, 20 and 28 Gy as single and split doses to the whole eye. The vascular networks were prepared from retinal digests. Stereological methods were used to obtain the area of the retina and unbiased estimates of microvessel/artery/vein endothelial, pericyte and smooth muscle population, and vessel length. The retinal area increased progressively in the unirradiated, age-matched controls and in the retinas irradiated with 8 and 14 Gy, indicating uniform progressive retinal growth. No growth occurred after 20 and 28 Gy. Regression analysis of total endothelial cell number in all vessels (arteries, veins and capillaries) after irradiation documented a progressive time- and dose-dependent cell loss occurring over 15 to 24 months. The difference from controls was significant (P<0.01) after 28 Gy given in single and split doses and after 20 Gy given as a split dose (P<0.05). Total vessel length in microvessel was significantly shortened at 20 and 28 Gy compared to that of controls (P<0.05). No evident dose recovery was observed in the endothelial populations after split doses. At 10 Gy, the rate of endothelial cell loss, a dose parameter used to characterize the time- and dose-dependent loss of the endothelial population, was doubled.

  14. Quantification of rat retinal growth and vascular population changes after single and split doses of proton irradiation: translational study using stereology methods

    NASA Technical Reports Server (NTRS)

    Mao, Xiao W.; Archambeau, John O.; Kubinova, Lucie; Boyle, Soames; Petersen, Georgia; Grove, Roger; Nelson, G. A. (Principal Investigator)

    2003-01-01

    This study quantified architectural and population changes in the rat retinal vasculature after proton irradiation using stereology. A 100 MeV conformal proton beam delivered 8, 14, 20 and 28 Gy as single and split doses to the whole eye. The vascular networks were prepared from retinal digests. Stereological methods were used to obtain the area of the retina and unbiased estimates of microvessel/artery/vein endothelial, pericyte and smooth muscle population, and vessel length. The retinal area increased progressively in the unirradiated, age-matched controls and in the retinas irradiated with 8 and 14 Gy, indicating uniform progressive retinal growth. No growth occurred after 20 and 28 Gy. Regression analysis of total endothelial cell number in all vessels (arteries, veins and capillaries) after irradiation documented a progressive time- and dose-dependent cell loss occurring over 15 to 24 months. The difference from controls was significant (P<0.01) after 28 Gy given in single and split doses and after 20 Gy given as a split dose (P<0.05). Total vessel length in microvessel was significantly shortened at 20 and 28 Gy compared to that of controls (P<0.05). No evident dose recovery was observed in the endothelial populations after split doses. At 10 Gy, the rate of endothelial cell loss, a dose parameter used to characterize the time- and dose-dependent loss of the endothelial population, was doubled.

  15. Protective effect of Schizandrin B against damage of UVB irradiated skin cells depend on inhibition of inflammatory pathways.

    PubMed

    Gao, Chenguang; Chen, Hong; Niu, Cong; Hu, Jie; Cao, Bo

    2017-01-02

    Schizandrin B is extracted from Schisandra chinensis (Turcz.) Baill. This study evaluated the photoprotective effect of Schizandrin B on oxidative stress injury of the skin caused by UVB-irradiation and the molecular mechanism of the photoprotective effect of Schizandrin B, and we firstly found that Schizandrin B could block Cox-2, IL-6 and IL-18 signal pathway to protect damage of skin cells given by UVB-irradiation. In the research, we found that Schizandrin B can attenuate the UVB-induced toxicity on keratinocytes and dermal fibroblasts in human body, and can outstandingly eliminated intracellular ROS produced by UVB-irradiation. These results demonstrate that Schizandrin B can regulate the function of decreasing intracellular SOD's activity and increasing the expression level of MDA in HaCaT cells result from the guidance of UVB, and it markedly reduced the production of inflammatory factors such as Cox-2, IL-6 or IL-18, decreased the expression level of MMP-1, and interdicted degradation process of collagens in UVB-radiated cells. Therefore, skin keratinocytes can be effectively protected from UVB-radiated damage by Schizandrin B, and UVB-irradiation caused inflammatory responses can be inhibited by attenuating process of ROS generating.

  16. Inhibition of autophagy prevents irradiation-induced neural stem and progenitor cell death in the juvenile mouse brain.

    PubMed

    Wang, Yafeng; Zhou, Kai; Li, Tao; Xu, Yiran; Xie, Cuicui; Sun, Yanyan; Zhang, Yaodong; Rodriguez, Juan; Blomgren, Klas; Zhu, Changlian

    2017-03-23

    Radiotherapy is an effective tool in the treatment of malignant brain tumors. However, damage to brain stem and progenitor cells constitutes a major problem and is associated with long-term side effects. Autophagy has been shown to be involved in cell death, and the purpose of this study was to evaluate the effect of autophagy inhibition on neural stem and progenitor cell death in the juvenile brain. Ten-day-old selective Atg7 knockout (KO) mice and wild-type (WT) littermates were subjected to a single 6Gy dose of whole-brain irradiation. Cell death and proliferation as well as microglia activation and inflammation were evaluated in the dentate gyrus of the hippocampus and in the cerebellum at 6 h after irradiation. We found that cell death was reduced in Atg7 KO compared with WT mice at 6 h after irradiation. The number of activated microglia increased significantly in both the dentate gyrus and the cerebellum of WT mice after irradiation, but the increase was lower in the Atg7 KO mice. The levels of proinflammatory cytokines and chemokines decreased, especially in the cerebellum, in the Atg7 KO group. These results suggest that autophagy might be a potential target for preventing radiotherapy-induced neural stem and progenitor cell death and its associated long-term side effects.

  17. Testosterone delays vascular smooth muscle cell senescence and inhibits collagen synthesis via the Gas6/Axl signaling pathway.

    PubMed

    Chen, Yan-qing; Zhao, Jing; Jin, Cheng-wei; Li, Yi-hui; Tang, Meng-xiong; Wang, Zhi-hao; Zhang, Wei; Zhang, Yun; Li, Li; Zhong, Ming

    2016-06-01

    Testosterone deficiency is associated with a higher incidence of cardiovascular diseases in men. However, its effect on cell senescence, which plays a causal role in vascular aging, remains unclear. Here, we tested the hypothesis that testosterone alleviated vascular smooth muscle cell (VSMC) senescence and collagen synthesis via growth arrest-specific protein 6 (Gas6)/Axl- and Akt/FoxO1a-dependent pathways. Testosterone significantly ameliorated angiotensin II-induced VSMC senescence and collagen overexpression. In addition, testosterone inhibited angiotensin II-induced matrix metalloproteinase-2 (MMP-2) activity, which played a pivotal role in facilitating age-related collagen deposition. Testosterone increased the expression of tissue inhibitor of metalloproteinase-2 but decreased the expression of MMP-2 and membrane type-1 metalloproteinase which contributed to increase MMP-2 activity. The effects on VSMCs senescence and collagen synthesis were mediated by restoration of angiotensin II-induced downregulation of Gas6 and Axl expression and a subsequent reduction of Akt and FoxO1a phosphorylation. The effects of testosterone were reversed by a Gas6 blocker, Axl-Fc, and a specific inhibitor of Axl, R428. Treatment of VSMCs with PI3K inhibitor LY294002 abrogated the downregulating effect of testosterone on MMP-2 activity. Furthermore, when FoxO1a expression was silenced by using a specific siRNA, the inhibitory effect of testosterone on MMP-2 activity was revered as well, that indicated this process was Akt/FoxO1a dependence. Taken together, Gas6/Axl and Akt/FoxO1a were involved in protective effects of testosterone on VSMCs senescence and collagen synthesis. Our results provide a novel mechanism underlying the protective effect of testosterone on vascular aging and may serve as a theoretical basis for testosterone replacement therapy.

  18. 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

  19. Myricitrin inhibits PDGF-BB-stimulated vascular smooth muscle cell proliferation and migration through suppressing PDGFRβ/Akt/Erk signaling.

    PubMed

    Li, Jie; Zhang, Mei; Ma, Juanjuan

    2015-01-01

    Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) and the stimulation of platelet-derived growth factor (PDGF)-BB play major pathological processes involved in the development of cardiovascular diseases. As a result, the use of anti-proliferative and anti-migratory agents for VSMCs offers promise for the treatment of vascular disorders. Myricitrin is a naturally occurring phenolic compound which possesses antioxidant and anti-inflammatory activity. In this study, we investigate the inhibitory effect of myricitrin on PDGF-BB-induced VSMCs proliferation and migration. In accordance with these findings, myricitrin induced the arrest of cell cycle progression at G0/G1 phase. Myricitrin also decreased the expressions of G0/G1 specific regulatory proteins including cyclin D1, cyclin-dependent kinases (CDK) 4, cyclin E and CDK2, as well as increased the expression of p21 in PDGF-BB-induced VSMCs. Moreover, myricitrin inhibited PDGF-BB-induced phosphorylation of PDGFRβ, Akt and Erk1/2. These results suggest that myricitrin plays an important role in prevention of VSMCs proliferation and migration through the G0/G1 cell cycle arrest by PDGF signaling pathway. Thus, myricitrin is effective in reducing atherosclerotic process by blocking proliferation of VSMCs.

  20. Hypoxia-Inducible Factor Pathway Inhibition Resolves Tumor Hypoxia and Improves Local Tumor Control After Single-Dose Irradiation

    SciTech Connect

    Helbig, Linda; Koi, Lydia; Brüchner, Kerstin; Gurtner, Kristin; Hess-Stumpp, Holger; Unterschemmann, Kerstin; Pruschy, Martin; and others

    2014-01-01

    Purpose: To study the effects of BAY-84-7296, a novel orally bioavailable inhibitor of mitochondrial complex I and hypoxia-inducible factor 1 (HIF-1) activity, on hypoxia, microenvironment, and radiation response of tumors. Methods and Materials: UT-SCC-5 and UT-SCC-14 human squamous cell carcinomas were transplanted subcutaneously in nude mice. When tumors reached 4 mm in diameter BAY-84-7296 (Bayer Pharma AG) or carrier was daily administered to the animals. At 7 mm tumors were either excised for Western blot and immunohistologic investigations or were irradiated with single doses. After irradiation animals were randomized to receive BAY-84-7296 maintenance or carrier. Local tumor control was evaluated 150 days after irradiation, and the dose to control 50% of tumors (TCD{sub 50}) was calculated. Results: BAY-84-7296 decreased nuclear HIF-1α expression. Daily administration of inhibitor for approximately 2 weeks resulted in a marked decrease of pimonidazole hypoxic fraction in UT-SCC-5 (0.5% vs 21%, P<.0001) and in UT-SCC-14 (0.3% vs 19%, P<.0001). This decrease was accompanied by a significant increase in fraction of perfused vessels in UT-SCC-14 but not in UT-SCC-5. Bromodeoxyuridine and Ki67 labeling indices were significantly reduced only in UT-SCC-5. No significant changes were observed in vascular area or necrosis. BAY-84-7296 before single-dose irradiation significantly decreased TCD{sub 50}, with an enhancement ratio of 1.37 (95% confidence interval [CI] 1.13-1.72) in UT-SCC-5 and of 1.55 (95% CI 1.26-1.94) in UT-SCC-14. BAY-84-7296 maintenance after irradiation did not further decrease TCD{sub 50}. Conclusions: BAY-84-7296 resulted in a marked decrease in tumor hypoxia and substantially reduced radioresistance of tumor cells with the capacity to cause a local recurrence after irradiation. The data suggest that reduction of cellular hypoxia tolerance by BAY-84-7296 may represent the primary biological mechanism underlying the observed enhancement of

  1. Inhibited flammability and surface inactivation of wood irradiated by low energy hydrogen ion showers (LEHIS)

    NASA Astrophysics Data System (ADS)

    Blantocas, Gene Q.; Mateum, Philip Edward R.; Orille, Ross William M.; Ramos, Rafael Julius U.; Monasterial, Jonathan Lee C.; Ramos, Henry J.; Bo-ot, Luis Ma. T.

    2007-06-01

    Changes on the properties of wood irradiated by low energy hydrogen ion showers (LEHIS) were examined. The experimental facility employed was an in-house constructed, compact gas discharge ion source with beam energies maintained approximately in the 1 keV range fixed at 1 mA discharge current, 3 mTorr gas filling pressure. Wood specimens used were of species endemic in the Philippines namely Shorea sp., Shorea polysperma and Cocos nucifera. Results showed the processed samples manifested characteristics of inhibited flammability, and became relatively hydrophobic after the treatment. In the fire resistance test, it was also observed during initial flaming that the processed surfaces accumulated less soot attesting to a much lower smoldering rate, i.e. lesser combustibility. To assess the increase in fire endurance time for the processed wood against the control substrates, a non-directional, two-tailed t-test was utilized. Significant at the 0.05 level, the t-statistic measured 9.164 as opposed to only 4.303 in its corresponding critical value at two degrees of freedom. Hence, the treatment appeared to show strong statistical evidence of being effective in enhancing fire resistance. The processed specimens also exhibited moisture absorptive inhibition time of more than 10 min versus an average absorption period of just 8 s for the unprocessed samples. Spectroscopy using a cast steel mass analyzer indicated a predominance of H+ with faint signals of H2+in the ion showers. It is hypothesized that the monatomic ion plays an essential participatory role in the surface modification process. Data from an earlier work using Narra wood (Pterocarpus indicus) [G.Q. Blantocas, H.J. Ramos, M. Wada, Jpn. J. Appl. Phys. 45 (2006) 8498] was extended in the current study to substantiate this hypothesis. The data is now presented as current density ratio H+ /H2+versus the change rate constant K of the wetting model equation. It is shown that wood affinity to water decreased as the

  2. Inhibition of Proliferation of Vascular Smooth Muscle Cells by Cucurbitanes from Momordica charantia.

    PubMed

    Tuan, Nguyen Quoc; Lee, Do-Hyung; Oh, Joonseok; Kim, Chung Sub; Heo, Kyung-Sun; Myung, Chang-Seon; Na, MinKyun

    2017-07-28

    The cucurbitaceous plant Momordica charantia L., named "bitter melon", inhabits Asia, Africa, and South America and has been used as a traditional medicine. The atypical proliferation of vascular smooth muscle cells (VSMCs) plays an important role in triggering the pathogenesis of cardiovascular diseases. Platelet-derived growth factor (PDGF) is regarded as the most powerful growth factor in promoting the intimal accumulation of VSMCs. The current study features the identification of six new cucurbitane-type triterpenoids (1-6) from the fruits of M.  charantia, utilizing diverse chromatographic and spectroscopic techniques. In particular, the 2D structure of 1 was confirmed utilizing the long-range HSQMBC NMR pulse, capable of measuring heteronuclear long-range correlations ((4-6)JCH). The cucurbitanes were also assessed for their inhibitory activity against PDGF-induced VSMC proliferation. This current study may constitute a basis for developing those chemotypes into sensible pharmacophores alleviating cardiovascular disorders.

  3. Phosphorylation of GATA-6 is required for vascular smooth muscle cell differentiation after mTORC1 inhibition

    PubMed Central

    Xie, Yi; Jin, Yu; Merenick, Bethany L.; Ding, Min; Fetalvero, Kristina M.; Wagner, Robert J.; Mai, Alice; Gleim, Scott; Tucker, David; Birnbaum, Morris J.; Ballif, Bryan A.; Luciano, Amelia K.; Sessa, William C.; Rzucidlo, Eva M.; Powell, Richard J.; Hou, Lin; Zhao, Hongyu; Hwa, John; Yu, Jun; Martin, Kathleen A.

    2015-01-01

    Vascular smooth muscle cells (VSMCs) undergo transcriptionally regulated reversible differentiation in growing and injured blood vessels. This de-differentiation also contributes to VSMC hyperplasia following vascular injury, including that caused by angioplasty and stenting. Stents provide mechanical support and can contain and release rapamycin, an inhibitor of the mammalian target of rapamycin complex 1 (mTORC1). Rapamycin suppresses VSMC hyperplasia and promotes VSMC differentiation. We report that rapamycin-induced differentiation of VSMCs required the transcription factor GATA-6. Inhibition of mTORC1 stabilized GATA-6 and promoted the nuclear accumulation of GATA-6, its binding to DNA, and its transactivation of promoters encoding contractile proteins and inhibitors of proliferation. These effects were mediated by phosphorylation of GATA-6 at Ser290, potentially by Akt2, a kinase that is activated in VSMCs when mTORC1 is inhibited. Rapamycin induced phosphorylation of GATA-6 in wild-type mice, but not in Akt2−/− mice. Intimal hyperplasia after arterial injury was greater in Akt2−/− mice than in wild-type mice, and the exacerbated response in Akt2−/− mice was rescued to a greater extent by local overexpression of the wild-type or phosphomimetic (S290D) mutant GATA-6 than by that of the phosphorylation-deficient (S290A) mutant. Our data indicated that GATA-6 and Akt2 are involved in the mTORC1-mediated regulation of VSMC proliferation and differentiation. Identifying the downstream transcriptional targets of mTORC1 may provide cell type-specific drug targets to combat cardiovascular diseases associated with excessive proliferation of VSMCs. PMID:25969542

  4. 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

  5. Cilostazol inhibits uremic toxin-induced vascular smooth muscle cell dysfunction: role of Axl signaling.

    PubMed

    Lee, Chien-Hsing; Hung, Yi-Jen; Shieh, Yi-Shing; Chien, Chu-Yen; Hsu, Yu-Juei; Lin, Chih-Yuan; Chiang, Chi-Fu; Huang, Chia-Luen; Hsieh, Chang-Hsun

    2017-03-01

    Chronic kidney disease (CKD) is associated with increased cardiovascular mortality, and vascular smooth muscle cell (VSMC) dysfunction plays a pivotal role in uremic atherosclerosis. Axl signaling is involved in vascular injury and is highly expressed in VSMCs. Recent reports have shown that cilostazol, a phosphodiesterase type 3 inhibitor (PDE3), can regulate various stages of the atherosclerotic process. However, the role of cilostazol in uremic vasculopathy remains unclear. This study aimed to identify the effect of cilostazol in VSMCs in the experimental CKD and to investigate whether the regulatory mechanism occurs through Axl signaling. We investigated the effect of P-cresol and cilostazol on Axl signaling in A7r5 rat VSMCs and the rat and human CKD models. From the in vivo CKD rats and patients, aortic tissue exhibited significantly decreased Axl expression after cilostazol treatment. P-cresol increased Axl, proliferating of cell nuclear antigen (PCNA), focal adhesion kinase (FAK), and matrix metalloproteinase-2 (MMP-2) expressions, decreased caspase-3 expression, and was accompanied by increased cell viability and migration. Cilostazol significantly reversed P-cresol-induced Axl, downstream gene expressions, and cell functions. Along with the increased Axl expression, P-cresol activated PLCγ, Akt, and ERK phosphorylation and cilostazol significantly suppressed the effect of P-cresol. Axl knockdown significantly reversed the expressions of P-cresol-induced Axl-related gene expression and cell functions. Cilostazol with Axl knockdown have additive changes in downstream gene expression and cell functions in P-cresol culture. Both in vitro and in vivo experimental CKD models elucidate a new signal transduction of cilostazol-mediated protection against uremic toxin-related VSMCs dysfunction and highlight the involvement of the Axl signaling and downstream pathways. Copyright © 2017 the American Physiological Society.

  6. Magnesium Inhibits Wnt/β-Catenin Activity and Reverses the Osteogenic Transformation of Vascular Smooth Muscle Cells

    PubMed Central

    Montes de Oca, Addy; Guerrero, Fatima; Martinez-Moreno, Julio M.; Madueño, Juan A.; Herencia, Carmen; Peralta, Alan; Almaden, Yolanda; Lopez, Ignacio; Aguilera-Tejero, Escolastico; Gundlach, Kristina; Büchel, Janine; Peter, Mirjam E.; Passlick-Deetjen, Jutta; Rodriguez, Mariano; Muñoz-Castañeda, Juan R.

    2014-01-01

    Magnesium reduces vascular smooth muscle cell (VSMC) calcification in vitro but the mechanism has not been revealed so far. This work used only slightly increased magnesium levels and aimed at determining: a) whether inhibition of magnesium transport into the cell influences VSMC calcification, b) whether Wnt/β-catenin signaling, a key mediator of osteogenic differentiation, is modified by magnesium and c) whether magnesium can influence already established vascular calcification. Human VSMC incubated with high phosphate (3.3 mM) and moderately elevated magnesium (1.4 mM) significantly reduced VSMC calcification and expression of the osteogenic transcription factors Cbfa-1 and osterix, and up-regulated expression of the natural calcification inhibitors matrix Gla protein (MGP) and osteoprotegerin (OPG). The protective effects of magnesium on calcification and expression of osteogenic markers were no longer observed in VSMC cultured with an inhibitor of cellular magnesium transport (2-aminoethoxy-diphenylborate [2-APB]). High phosphate induced activation of Wnt/β-catenin pathway as demonstrated by the translocation of β-catenin into the nucleus, increased expression of the frizzled-3 gene, and downregulation of Dkk-1 gene, a specific antagonist of the Wnt/β-catenin signaling pathway. The addition of magnesium however inhibited phosphate-induced activation of Wnt/β-catenin signaling pathway. Furthermore, TRPM7 silencing using siRNA resulted in activation of Wnt/β-catenin signaling pathway. Additional experiments were performed to test the ability of magnesium to halt the progression of already established VSMC calcification in vitro. The delayed addition of magnesium decreased calcium content, down-regulated Cbfa-1 and osterix and up-regulated MGP and OPG, when compared with a control group. This effect was not observed when 2-APB was added. In conclusion, magnesium transport through the cell membrane is important to inhibit VSMC calcification in vitro

  7. Non-genomic mechanism of 17 beta-oestradiol-induced inhibition of contraction in mammalian vascular smooth muscle.

    PubMed Central

    Kitazawa, T; Hamada, E; Kitazawa, K; Gaznabi, A K

    1997-01-01

    17 beta-Oestradiol (E2) at 0.1-10 microM directly inhibited various tonic and phasic smooth muscle contractions. The mechanism(s) of oestrogen-induced inhibition of contraction was studied using intact and permeabilized strips and isolated single cells of smooth muscle. 2. In endothelium-denuded vascular smooth muscle, E2 attenuated high K(+)-induced force development and myosin light chain phosphorylation, and produced rapid and reversible relaxation. There were no significant differences in these inhibitory effects between tissue types (femoral artery vs. portal vein), species (rat vs. rabbit) or sexes. 3. The inhibitory potencies of several steroidal and non-steroidal oestrogen analogues were examined and their effects were for the most part stereo-specific. However, two steroids with negligible affinities for the nuclear oestrogen receptor also strongly inhibited high K(+)-induced contraction. 4. Genomic modulators including a protein synthesis inhibitor, an RNA synthesis inhibitor, and oestrogen receptor antagonists did not affect the inhibitory actions of E2. Inhibitors of cyclic nucleotide-dependent protein kinases did not reduce the E2 effect. 5. Ca2+ release from intracellular stores by agonists and by inositol 1,4,5-trisphosphate (IP3) does not appear to be modulated by E2. Neither pretreatment with ryanodine nor with thapsigargin affected the E2-induced inhibition of high K(+)-induced contraction. 6. E2 had no effect on either normal or GTP gamma S-increased Ca2+ sensitivity of the regulatory and contractile apparatus. 7. E2 and its analogues rapidly inhibited voltage-dependent L-type Ca2+ channel currents in isolated smooth muscle cells. Repetitive stimulation was not required for E2-induced inhibition of the currents. 8. This study strongly suggests that at pharmacological concentrations oestrogen primarily reduces Ca2+ influx through inhibition of L-type Ca2+ channels in a non-genomic manner and decreases myosin light chain phosphorylation and

  8. A new and potent calmodulin antagonist, HF-2035, which inhibits vascular relaxation induced by nitric oxide synthase.

    PubMed

    Win, N H; Ishikawa, T; Saito, N; Kato, M; Yokokura, H; Watanabe, Y; Iida, Y; Hidaka, H

    1996-03-28

    HF-2035, 2-[N-(2-aminoethyl)-N-(2,4,5-trichlorobenzenesulfonyl)] amino-N-(4-chlorocinnamyl)-N-methylbenzylamine, was synthesized and its effects on calmodulin-dependent enzymes were investigated. HF-2035 inhibited calmodulin kinase I, calmodulin kinase II and myosin light-chain kinase with IC50 values of 1.3 microM, 1.6 microM and 68 microM, respectively. HF-2035 also inhibited the activity of recombinant rat neuronal nitric oxide synthase, one of the calmodulin-dependent enzymes, with a Ki of 0.78 microM. Partially purified nitric oxide synthase of rat brain was also inhibited by HF-2035 with an IC50 of 3.2 microM. Kinetic analysis indicated that this inhibitory effect of HF-2035 was competitive with respect to calmodulin. We examined the effects of HF-2035 on constitutive nitric oxide synthase in a bioassay using vascular strips of rabbit carotid artery with and without endothelium. HF-2035 inhibited acetylcholine- and calcium ionophore, A23187 (6S-[6 alpha (2S*,3S*),8 beta (R*),9 beta, 11 alpha]-5- (methylamino)-2-[[3,9,11-trimethyl-8-[1-methyl-2-oxo-2-(1H-pyrrol-2-yl)- ethyl]-1,7-dioxaspiro[5.5]undec-2-yl]methyl]-4-benzoxazol ecarboxylic acid)-induced relaxation of endothelium-intact strips with an ED50 of 1.5 +/- 0.5 microM and 2.8 +/- 1 microM, respectively. This compound, however, did not inhibit N-nitroso-N-morpholinoaminoacetonitrile (SIN-1A), an exogenous nitric oxide donor, -induced relaxation of endothelium-denuded strips. W-7 (N-(6-aminohexyl)-5-chloro-1- naphthalenesulfonamide) inhibited acetylcholine-induced relaxation with an ED50 of 46 +/- 7 microM, which was 30-fold less potent than HF-2035. HF-2035 was unable to inhibit the activity of the inducible form of nitric oxide synthase in isolated thoracic aorta of rat treated with Escherichia coli lipopolysaccharide. These findings suggest that HF-2035 is a new and potent calmodulin antagonist, and may be used as a mother compound to develop more selective inhibitors of constitutive nitric oxide

  9. 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

  10. 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

  11. 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.

  12. 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

  13. Regeneration of Murine Hair Follicles is Inhibited by Low-Dose-Rate Gamma Irradiation.

    PubMed

    Sugaya, Kimihiko; Hirobe, Tomohisa; Ishihara, Yoshie; Inoue, Sonoe

    2016-10-01

    To determine whether the effects of low-dose-rate gamma (γ) irradiation are identifiable in the regeneration of murine hair follicles, we irradiated whole bodies of C57BL/10JHir mice in the first telogen phase of the hair cycle with (137)Cs γ-rays. The mice were examined for effects on hair follicles, including number, morphology, and pigmentation in the second anagen phase. Effects of γ-radiation on melanocyte stem cells were also investigated by the indirect immunolabeling of tyrosinase-related protein 2 (TRP2). Irradiated skin showed a decrease in hair follicle density and the induction of curved hair follicles along with the presence of white hairs and hypopigmented hair bulbs. There was a small, but not significant, change in the number of TRP2-positive melanocyte stem cells in the hair bulge region of the irradiated skin. These results suggest that low-dose rate γ-irradiation does not deplete melanocyte stem cells, but can damage stem cells and progenitors for both keratinocytes and melanocytes, thereby affecting the structure and pigmentation of regenerated hair follicles in the 2(nd) anagen phase.

  14. Inhibition of phosphatidylserine recognition heightens the immunogenicity of irradiated lymphoma cells in vivo.

    PubMed

    Bondanza, Attilio; Zimmermann, Valérie S; Rovere-Querini, Patrizia; Turnay, Javier; Dumitriu, Ingrid E; Stach, Christian M; Voll, Reinhard E; Gaipl, Udo S; Bertling, Wolf; Pöschl, Ernst; Kalden, Joachim R; Manfredi, Angelo A; Herrmann, Martin

    2004-11-01

    Strategies to enhance the immunogenicity of tumors are urgently needed. Although vaccination with irradiated dying lymphoma cells recruits a tumor-specific immune response, its efficiency as immunogen is poor. Annexin V (AxV) binds with high affinity to phosphatidylserine on the surface of apoptotic and necrotic cells and thereby impairs their uptake by macrophages. Here, we report that AxV preferentially targets irradiated lymphoma cells to CD8+ dendritic cells for in vivo clearance, elicits the release of proinflammatory cytokines and dramatically enhances the protection elicited against the tumor. The response was endowed with both memory, because protected animals rejected living lymphoma cells after 72 d, and specificity, because vaccinated animals failed to reject unrelated neoplasms. Finally, AxV-coupled irradiated cells induced the regression of growing tumors. These data indicate that endogenous adjuvants that bind to dying tumor cells can be exploited to target tumors for immune rejection.

  15. Inhibition of mTOR by apigenin in UVB-irradiated keratinocytes: A new implication of skin cancer prevention.

    PubMed

    Bridgeman, Bryan B; Wang, Pu; Ye, Boping; Pelling, Jill C; Volpert, Olga V; Tong, Xin

    2016-05-01

    Ultraviolet B (UVB) radiation is the major environmental risk factor for developing skin cancer, the most common cancer worldwide, which is characterized by aberrant activation of Akt/mTOR (mammalian target of rapamycin). Importantly, the link between UV irradiation and mTOR signaling has not been fully established. Apigenin is a naturally occurring flavonoid that has been shown to inhibit UV-induced skin cancer. Previously, we have demonstrated that apigenin activates AMP-activated protein kinase (AMPK), which leads to suppression of basal mTOR activity in cultured keratinocytes. Here, we demonstrated that apigenin inhibited UVB-induced mTOR activation, cell proliferation and cell cycle progression in mouse skin and in mouse epidermal keratinocytes. Interestingly, UVB induced mTOR signaling via PI3K/Akt pathway, however, the inhibition of UVB-induced mTOR signaling by apigenin was not Akt-dependent. Instead, it was driven by AMPK activation. In addition, mTOR inhibition by apigenin in keratinocytes enhanced autophagy, which was responsible, at least in part, for the decreased proliferation in keratinocytes. In contrast, apigenin did not alter UVB-induced apoptosis. Taken together, our results indicate the important role of mTOR inhibition in UVB protection by apigenin, and provide a new target and strategy for better prevention of UV-induced skin cancer.

  16. Inhibition of mTOR by apigenin in UVB-irradiated keratinocytes: A new implication of skin cancer prevention

    PubMed Central

    Ye, Boping; Pelling, Jill C.; Volpert, Olga V.; Tong, Xin

    2016-01-01

    Ultraviolet B (UVB) radiation is the major environmental risk factor for developing skin cancer, the most common cancer worldwide, which is characterized by a berrant activation of Akt/mTOR (mammalian target of rapamycin). Importantly, the link between UV irradiation and mTOR signaling has not been fully established. Apigenin is a naturally occurring flavonoid that has been shown to inhibit UV-induced skin cancer. Previously, we have demonstrated that apigenin activates AMP-activated protein kinase (AMPK), which leads to suppression of basal mTOR activity in cultured keratinocytes. Here, we demonstrated that apigenin inhibited UVB-induced mTOR activation, cell proliferation and cell cycle progression in mouse skin and in mouse epidermal keratinocytes. Interestingly, UVB induced mTOR signaling via PI3K/Akt pathway, however, the inhibition of UVB-induced mTOR signaling by apigenin was not Akt-dependent. Instead, it was driven by AMPK activation. In addition, mTOR inhibition by apigenin in keratinocytes enhanced autophagy, which was responsible, at least in part, for the decreased proliferation in keratinocytes. In contrast, apigenin did not alter UVB-induced apoptosis. Taken together, our results indicate the important role of mTOR inhibition in UVB protection by apigenin, and provide a new target and strategy for better prevention of UV-induced skin cancer. PMID:26876613

  17. Activation of Cell Surface Bound 20S Proteasome Inhibits Vascular Cell Growth and Arteriogenesis

    PubMed Central

    Ito, Wulf D.; Lund, Natalie; Zhang, Ziyang; Buck, Friedrich; Lellek, Heinrich; Horst, Andrea; Machens, Hans-Günther; Schunkert, Heribert; Schaper, Wolfgang; Meinertz, Thomas

    2015-01-01

    Arteriogenesis is an inflammatory process associated with rapid cellular changes involving vascular resident endothelial progenitor cells (VR-EPCs). Extracellular cell surface bound 20S proteasome has been implicated to play an important role in inflammatory processes. In our search for antigens initially regulated during collateral growth mAb CTA 157-2 was generated against membrane fractions of growing collateral vessels. CTA 157-2 stained endothelium of growing collateral vessels and the cell surface of VR-EPCs. CTA 157-2 bound a protein complex (760 kDa) that was identified as 26 kDa α7 and 21 kDa β3 subunit of 20S proteasome in mass spectrometry. Furthermore we demonstrated specific staining of 20S proteasome after immunoprecipitation of VR-EPC membrane extract with CTA 157-2 sepharose beads. Functionally, CTA 157-2 enhanced concentration dependently AMC (7-amino-4-methylcoumarin) cleavage from LLVY (N-Succinyl-Leu-Leu-Val-Tyr) by recombinant 20S proteasome as well as proteasomal activity in VR-EPC extracts. Proliferation of VR-EPCs (BrdU incorporation) was reduced by CTA 157-2. Infusion of the antibody into the collateral circulation reduced number of collateral arteries, collateral proliferation, and collateral conductance in vivo. In conclusion our results indicate that extracellular cell surface bound 20S proteasome influences VR-EPC function in vitro and collateral growth in vivo. PMID:26146628

  18. Aprotinin Inhibits Vascular Smooth Muscle Cell Inflammation and Proliferation via Induction of HO-1

    PubMed Central

    Lee, Dong Hyup; Choi, Hyoung Chul; Lee, Kwang Youn

    2009-01-01

    Aprotinin is used clinically in cardiopulmonary bypass surgery to reduce transfusion requirements and the inflammatory response. The mechanism of action for the anti-inflammatory effects of aprotinin is still unclear. We examined our hypothesis whether inhibitory effects of aprotinin on cytokine-induced inducible nitric oxide synthase (iNOS) expression (IL-1β plus TNF-α), reactive oxygen species (ROS) generation, and vascular smooth muscle cell (VSMC) proliferation were due to HO-1 induction in rat VSMCs. Aprotinin induced HO-1 protein expression in a dose-dependent manner, which was potentiated during inflammatory condition. Aprotinin reduced cytokine mixture (CM)-induced iNOS expression in a dose dependent manner. Furthermore, aprotinin reduced CM-induced ROS generation, cell proliferation, and phosphorylation of JNK but not of P38 and ERK1/2 kinases. Aprotinin effects were reversed by pre-treatment with the HO-1 inhibitor, tin protoporphyrin IX (SnPPIX). HO-1 is therefore closely involved in inflammatory-stimulated VSMC proliferation through the regulation of ROS generation and JNK phosphorylation. Our results suggest a new molecular basis for aprotinin anti-inflammatory properties. PMID:19885007

  19. 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

  20. MiR-21 inhibits c-Ski signaling to promote the proliferation of rat vascular smooth muscle cells.

    PubMed

    Li, Jun; Zhao, Li; He, Xie; Yang, Ting; Yang, Kang

    2014-04-01

    Previously, we reported that the decrease of endogenous c-Ski expression is implicated in the progression of vascular smooth muscle cell (VSMC) proliferation after arterial injury. However, the molecular mechanism of the down-regulation of c-Ski is not clear. In this study, a potential miR-21 recognition element was identified in the 3'-untranslated region (UTR) of rat c-Ski mRNA. A reporter assay revealed that miR-21 could recognize the miR-21 recognition element of c-Ski mRNA. In A10 rat aortic smooth muscle cells, overexpression of miR-21 significantly inhibited the expression of c-Ski protein and promoted cell proliferation, which could be blocked by inhibition of miR-21 or overexpression of c-Ski. Further investigation demonstrated that the effect of miR-21 on VSMC proliferation resulted from negative regulation of c-Ski to suppress p38-p21/p27 signaling, the downstream pathway of c-Ski in VSMCs. These results indicate that c-Ski is a target gene of miR-21. miR-21 specifically binds to the 3'-untranslated region of c-Ski and negatively regulates c-Ski expression to diminish the protective effects of c-Ski and stimulate VSMC proliferation in the progression of arterial injury.

  1. Overexpression of membrane sialic acid-specific sialidase Neu3 inhibits matrix metalloproteinase-9 expression in vascular smooth muscle cells

    SciTech Connect

    Moon, Sung-Kwon; Cho, Seung-Hak; Kim, Kyung-Woon; Jeon, Jae Heung; Ko, Jeong-Heon; Kim, Bo Yeon; Kim, Cheorl-Ho . E-mail: chkimbio@skku.edu

    2007-05-11

    The ganglioside-specific sialidase Neu3 has been suggested to participate in cell growth, migration, and differentiation. Recent reports suggest that sialidase may be involved in intimal thickening, an early stage in the development of atherosclerosis. However, the role of the Neu3 gene in vascular smooth muscle cells (VSMC) responses has not yet been elucidated. To determine whether a Neu3 is able to modulate VSMC growth, the effect of overexpression of the Neu3 gene on cell proliferation was examined. However, the results show that the overexpression of this gene has no effect on DNA synthesis and ERK phosphorylation in cultured VSMC in the presence of TNF-{alpha}. Because atherogenic effects need not be limited to proliferation, we decided to examine whether Neu3 exerted inhibitory effects on matrix metalloproteinase-9 (MMP-9) activity in TNF-{alpha}-induced VSMC. The expression of the Neu3 gene led to the inhibition of TNF-{alpha}-induced matrix metalloproteinase-9 (MMP-9) expression in VSMC as determined by zymography and immunoblot. Furthermore, Neu3 gene expression strongly decreased MMP-9 promoter activity in response to TNF-{alpha}. This inhibition was characterized by the down-regulation of MMP-9, which was transcriptionally regulated at NF-{kappa}B and activation protein-1 (AP-1) sites in the MMP-9 promoter. These findings suggest that the Neu3 gene represents a physiological modulator of VSMC responses that may contribute to plaque instability in atherosclerosis.

  2. Paeonol Inhibits the Proliferation, Invasion, and Inflammatory Reaction Induced by TNF-α in Vascular Smooth Muscle Cells.

    PubMed

    Meng, Liang; Xu, Weidong; Guo, Lihong; Ning, Wenqi; Zeng, Xiandong

    2015-11-01

    The aim of this study was to evaluate the effect of paeonol on the proliferation, migration, and inflammation induced by tumor necrosis factor (TNF-α) of rat vascular smooth muscle cells (VSMCs). Primary rat VSMCs were identified by immunofluorescence assay. The inhibition of VSMCs proliferation induced by TNF-α was observed after paeonol treatment in a dose-dependent manner. Treatment with 100 μM paeonol significantly reduced the expression of proliferating cell nuclear antigen (PCNA). On the other hand, transwell assay showed that treatment with paeonol suppressed the invasion of TNF-α-induced VSMCs and the production of inflammation factors stimulated by TNF-α. For apoptosis induced by paeonol, Western blot analysis showed that cleaved caspase-3 and -9 were detected, and pro-apoptotic protein Bax was up-regulated, whereas anti-apoptotic protein Bcl-2 was down-regulated by paeonol in TNF-α-stimulated VSMCs. ELISA analysis data showed that both levels of IL-1β and IL-6 produced by the stimulation of TNF-α were decreased by paeonol in a dose-dependent manner in VSMCs. These results suggest that paeonol can effectively inhibit the proliferation through apoptotic induction through caspase pathway in VSMCs induced by TNF-α. Also, paeonol significantly reduced the invasion and the inflammation stimulated by TNF-α in VSMCs.

  3. Mulberry leaf extract inhibits the development of atherosclerosis in cholesterol-fed rabbits and in cultured aortic vascular smooth muscle cells.

    PubMed

    Chan, Kuei-Chuan; Yang, Mon-Yuan; Lin, Ming-Cheng; Lee, Yi-Ju; Chang, Wen-Chun; Wang, Chau-Jong

    2013-03-20

    This study used high-cholesterol-fed New Zealand white rabbits and aortic vascular smooth muscle cells (VSMCs) to investigate the impact of mulberry leaf extract (MLE) on the development of atherosclerosis. The results show that the major components of MLE are polyphenols, flavonoids, carbohydrates, proteins, and lipids, and the major contituents of mulberry leaf polyphenol extract (MLPE) are polyphenols and flavonoids. In addition to improvement of liver function, the atheroma burden and levels of serum cholesterol, triglycerides, and low-density lipoprotein (LDL) are also significantly reduced after MLE treatment. MLE and MLPE improved endothelial function, inhibited proliferation and migration of aortic VSMCs, and reduced atheromas in the vascular wall. In conclusion, this study demonstrates that, in addition to exerting hypolipidemic effects, MLE and MLPE can effectively inhibit proliferation and migration of aortic VSMCs, improve vascular endothelial function, and reduce atheroma burden, thereby preventing atherosclerosis.

  4. Reconstruction of the proximal humerus by combined use of extracorporeally-irradiated osteochondral graft and free vascularized fibula following resection of Ewing sarcoma.

    PubMed

    Muramatsu, Keiichi; Fukano, Reiji; Ihara, Koichiro; Iwanaga, Ryuta; Taguchi, Toshihiko

    2010-12-01

    Reconstruction of the proximal humerus following limb-saving resection of malignant bone tumor is extremely challenging. We describe here a novel anatomical reconstruction technique in a young patient. A 6-year-old girl with Ewing sarcoma of the proximal humerus was treated by wide excision of the tumor followed by reconstruction with extracorporeally-irradiated osteoarticular autograft combined with an intramedullary inserted free vascularized fibula graft. Proper alignment of the shoulder joint was maintained with no osteoarthritic changes after 16 months. The resulting limb function was satisfactory. This biological reconstruction method was safe and without serious complication. It is indicated for the reconstruction of non-weight-bearing joints and is ideal for the proximal humerus.

  5. Insulin Inhibits Low Oxygen-Induced ATP Release from Human Erythrocytes: Implication for Vascular Control

    PubMed Central

    Hanson, Madelyn S.; Ellsworth, Mary L.; Achilleus, David; Stephenson, Alan H.; Bowles, Elizabeth A.; Sridharan, Meera; Adderley, Shaquria; Sprague, Randy S.

    2010-01-01

    Objective ATP released from human erythrocytes in response to reduced oxygen tension (pO2) participates in the matching of oxygen (O2) supply with need in skeletal muscle by stimulating increases in blood flow to areas with increased O2 demand. Here we investigated the hypothesis that hyperinsulinemia inhibits ATP release from erythrocytes and impairs their ability to stimulate dilation of isolated arterioles exposed to decreased extra-luminal pO2. Methods Erythrocyte ATP release was stimulated pharmacologically (mastoparan 7) and physiologically (reduced pO2) in the absence or presence of insulin. We also examined the ability of isolated skeletal muscle arterioles perfused with buffer containing erythrocytes treated with insulin or its vehicle (saline) to dilate in response to decreased extra-luminal pO2. Results Insulin significantly attenuated mastoparan 7– and reduced pO2–induced ATP release. In vessels perfused with untreated erythrocytes, low extra-luminal pO2 resulted in an increase in vessel diameter. In contrast, when erythrocytes were treated with insulin, no vasodilation occurred. Conclusions These studies demonstrate that insulin inhibits ATP release from erythrocytes in response to reduced pO2 and impairs their ability to stimulate dilation of skeletal muscle arterioles. These results suggest that hyperinsulinemia could hinder the matching of O2 supply with need in skeletal muscle. PMID:19412833

  6. 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

  7. 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

  8. Inositol hexaphosphate inhibits tumor growth, vascularity, and metabolism in TRAMP mice: a multiparametric magnetic resonance study.

    PubMed

    Raina, Komal; Ravichandran, Kameswaran; Rajamanickam, Subapriya; Huber, Kendra M; Serkova, Natalie J; Agarwal, Rajesh

    2013-01-01

    Herein, employing anatomical and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI), we evaluated noninvasively, the in vivo, chemopreventive efficacy of inositol hexaphosphate (IP6), a major constituent of high-fiber diets, against prostate tumor growth and progression in transgenic adenocarcinoma of the mouse prostate (TRAMP) model. Male TRAMP mice, beginning at 4 weeks of age, were fed with 1%, 2%, or 4% (w/v) IP6 in drinking water or only drinking water till 28 weeks of age and monitored using MRI over the course of study. Longitudinal assessment of prostate volumes by conventional MRI and tumor vascularity by gadolinium-based DCE-MRI showed a profound reduction in tumor size, partly due to antiangiogenic effects by IP6 treatment. As potential mechanisms of IP6 efficacy, decrease in the expression of glucose transporter GLUT-4 protein together with an increase in levels of phospho-AMP-activated kinase (AMPK(Th172)) were observed in prostate tissues of mice from IP6 fed-groups, suggesting that IP6 is interfering with the metabolic events occurring in TRAMP prostate. Investigative metabolomics study using quantitative high-resolution (1)H-NMR on prostate tissue extracts showed that IP6 significantly decreased glucose metabolism and membrane phospholipid synthesis, in addition to causing an increase in myoinositol levels in the prostate. Together, these findings show that oral IP6 supplement blocks growth and angiogenesis of prostate cancer in the TRAMP model in conjunction with metabolic events involved in tumor sustenance. This results in energy deprivation within the tumor, suggesting a practical and translational potential of IP6 treatment in suppressing growth and progression of prostate cancer in humans. ©2012 AACR.

  9. Inositol Hexaphosphate Inhibits Tumor Growth, Vascularity, and Metabolism in TRAMP Mice: A Multiparametric Magnetic Resonance Study

    PubMed Central

    Raina, Komal; Ravichandran, Kameswaran; Rajamanickam, Subapriya; Huber, Kendra M.; Serkova, Natalie. J.; Agarwal, Rajesh

    2012-01-01

    Herein, employing anatomical and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI), we evaluated non-invasively, the in vivo, chemopreventive efficacy of inositol hexaphosphate (IP6), a major constituent of high fiber diets, against prostate tumor growth and progression in transgenic adenocarcinoma of the mouse prostate (TRAMP) model. Male TRAMP mice, beginning 4 weeks of age, were fed with 1, 2 or 4% (w/v) IP6 in drinking water or only drinking water till 28 weeks of age and monitored using MRI over the course of study. Longitudinal assessment of prostate volumes by conventional MRI and tumor vascularity by gadolinium-based DCE-MRI showed a profound reduction in tumor size partly due to anti-angiogenic effects by IP6 treatment. As potential mechanisms of IP6 efficacy, decrease in the expression of glucose transporter GLUT-4 protein together with an increase in levels of phospho-AMP-activated kinase (AMPKTh172) were observed in prostate tissues of mice from IP6 fed-groups, suggesting that IP6 is interfering with the metabolic events occurring in TRAMP prostate. Investigative metabolomics study utilizing quantitative high-resolution 1H-NMR on prostate tissue extracts showed that IP6 significantly decreased glucose metabolism and membrane phospholipid synthesis, in addition to causing an increase in myo-inositol levels in the prostate. Together, these findings show that oral IP6 supplement blocks PCa growth and angiogenesis in TRAMP model in conjunction with metabolic events involved in tumor sustenance. This results in energy deprivation within the tumor, suggesting a practical and translational potential of IP6 treatment in suppressing growth and progression of prostate cancer in humans. PMID:23213071

  10. Exogenous hydrogen sulfide inhibits superoxide formation, NOX-1 expression and Rac1 activity in human vascular smooth muscle cells.

    PubMed

    Muzaffar, Saima; Shukla, Nilima; Bond, Mark; Newby, Andrew C; Angelini, Gianni D; Sparatore, Anna; Del Soldato, Piero; Jeremy, Jamie Y

    2008-01-01

    The activity of NADPH oxidase (NOX) is blocked by nitric oxide (NO). Hydrogen sulfide (H(2)S) is also produced by blood vessels. It is reasonable to suggest that H(2)S may have similar actions to NO on NOX. In order to test this hypothesis, the effect of sodium hydrosulfide (NaHS) on O(2)(-) formation, the expression of NOX-1 (a catalytic subunit of NOX) and Rac(1) activity (essential for full NOX activity) in isolated vascular smooth muscle cells (hVSMCs) was investigated. hVSMCs were incubated with the thromboxane A(2) analogue U46619 +/- NaHS for 1 or 16 h, and O(2)(-) formation, NOX-1 expression and Rac(1) activity were assessed. The possible interaction between H(2)S and NO was also studied by using an NO synthase inhibitor, L-NAME, and an NO donor, DETA-NONOate. The role of K(ATP) channels was studied by using glibenclamide. NaHS inhibited O(2)(-) formation following incubation of 1 h (IC(50), 30 nM) and 16 h (IC(50), 20 nM), blocked NOX-1 expression and inhibited Rac(1) activity. These inhibitory effects of NaHS were mediated by the cAMP-protein-kinase-A axis. Exogenous H(2)S prevents NOX-driven intravascular oxidative stress through an a priori inhibition of Rac(1) and downregulation of NOX-1 protein expression, an effect mediated by activation of the adenylylcyclase-cAMP-protein-kinase-G system by H(2)S. Copyright 2008 S. Karger AG, Basel.

  11. 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

  12. Vasostatin-2 inhibits cell proliferation and adhesion in vascular smooth muscle cells, which are associated with the progression of atherosclerosis

    SciTech Connect

    Hou, Jianghong; Xue, Xiaolin; Li, Junnong

    2016-01-22

    Recently, the serum expression level of vasostatin-2 was found to be reduced and is being studied as an important indicator to assess the presence and severity of coronary artery disease; the functional properties of vasostatin-2 and its relationship with the development of atherosclerosis remains unclear. In this study, we attempted to detect the expression of vasostatin-2 and its impact on human vascular smooth muscle cells (VSMCs). Quantitative real-time PCR (qRT-PCR) and western blot were used to assess the expression level of vasostatin-2 in VSMCs between those from atherosclerosis and disease-free donors; we found that vasostatin-2 was significantly down-regulated in atherosclerosis patient tissues and cell lines. In addition, the over-expression of vasostatin-2 apparently inhibits cell proliferation and migration in VSMCs. Gain-of-function in vitro experiments further show that vasostatin-2 over-expression significantly inhibits inflammatory cytokines release in VSMCs. In addition, cell adhesion experimental analysis showed that soluble adhesion molecules (sICAM-1, sVCAM-1) had decreased expression when vasostatin-2 was over-expressed in VSMCs. Therefore, our results indicate that vasostatin-2 is an atherosclerosis-related factor that can inhibit cell proliferation, inflammatory response and cell adhesion in VSMCs. Taken together, our results indicate that vasostatin-2 could serve as a potential diagnostic biomarker and therapeutic option for human atherosclerosis in the near future. - Highlights: • Vasostatin-2 levels were down-regulated in atherosclerosis patient tissues and VSMCs. • Ectopic expression of vasostatin-2 directly affects cell proliferation and migration in vitro. • Ectopic expression of vasostatin-2 protein affects pro-inflammatory cytokines release in VSMCs. • Ectopic expression of vasostatin-2 protein affects cell adhesion in VSMCs.

  13. Effect of magnesium supplementation on blood pressure and vascular reactivity in nitric oxide synthase inhibition-induced hypertension model.

    PubMed

    Basralı, Filiz; Koçer, Günnur; Ülker Karadamar, Pınar; Nasırcılar Ülker, Seher; Satı, Leyla; Özen, Nur; Özyurt, Dilek; Şentürk, Ümit Kemal

    2015-01-01

    The aim of this study was to assess the effect of oral magnesium supplementation (Mg-supp) on blood pressure (BP) and possible mechanism in nitric oxide synthase (NOS) inhibition-induced hypertension model. Hypertension and/or Mg-supp were created by N-nitro-l-arginine methyl ester (25 mg/kg/day by drinking water) and magnesium-oxide (0.8% by diet) for 6 weeks. Systolic BP was measured weekly by tail-cuff method. The effects of hypertension and/or Mg-supp in thoracic aorta and third branch of mesenteric artery constriction and relaxation responses were evaluated. NOS-inhibition produced a gradually developing hypertension and the magnitude of the BP was significantly attenuated after five weeks of Mg-supp. The increased phenylephrine-induced contractile and decreased acetylcholine (ACh)-induced dilation responses were found in both artery segments of hypertensive groups. Mg-supp was restored ACh-relaxation response in both arterial segments and also Phe-constriction response in thoracic aorta but not in mesenteric arteries. The contributions of NO, prostaglandins and K(+) channels to the dilator response of ACh were similar in the aorta of all the groups. The contribution of the NO to the ACh-mediated relaxation response of mesenteric arteries was suppressed in hypertensive rats, whereas this was corrected by Mg-supp. The flow-mediated dilation response of mesenteric arteries in hypertensive rats failed and could not be corrected by Mg-supp. Whereas, vascular eNOS protein and magnesium levels were not changed and plasma nitrite levels were reduced in hypertensive rats. The results of this study showed that Mg-supp lowered the arterial BP in NOS-inhibition induced hypertension model by restoring the agonist-induced relaxation response of the arteries.

  14. Overproduction of single-stranded-DNA-binding protein specifically inhibits recombination of UV-irradiated bacteriophage DNA in Escherichia coli.

    PubMed Central

    Moreau, P L

    1988-01-01

    Overproduction of single-stranded DNA (ssDNA)-binding protein (SSB) in uvr Escherichia coli mutants results in a wide range of altered phenotypes. (i) Cell survival after UV irradiation is decreased; (ii) expression of the recA-lexA regulon is slightly reduced after UV irradiation, whereas it is increased without irradiation; and (iii) recombination of UV-damaged lambda DNA is inhibited, whereas recombination of nonirradiated DNA is unaffected. These results are consistent with the idea that in UV-damaged bacteria, SSB is first required to allow the formation of short complexes of RecA protein and ssDNA that mediate cleavage of the LexA protein. However, in a second stage, SSB should be displaced from ssDNA to permit the production of longer RecA-ssDNA nucleoprotein filaments that are required for strand pairing and, hence, recombinational repair. Since bacteria overproducing SSB appear identical in physiological respects to recF mutant bacteria, it is suggested that the RecF protein (alone or with other proteins of the RecF pathway) may help RecA protein to release SSB from ssDNA. PMID:2836358

  15. Inhibition of uracil-DNA glycosylase increases SCEs in BrdU-treated and visible light-irradiated cells

    SciTech Connect

    Maldonado, A.; Hernandez, P.; Gutierrez, C.

    1985-11-01

    The authors have approached the study of the ability of different types of lesions produced by DNA-damaging agents to develop sister-chromatid exchanges (SCEs) by analyzing SCE levels observed in Allium cepa L cells with BrdU-substituted DNA and exposed to visible light (VL), an irradiation which produces uracil residues in DNA after debromination of bromouracil and enhances SCE levels but only above a certain dose. They have partially purified an uracil-DNA glycosylase activity from A. cepa L root meristem cells, which removes uracil from DNA, the first step in the excision repair of this lesion. This enzyme was inhibited in vitro by 6-amino-uracil and uracil but not by thymine. When cells exposed to VL, at a dose that did not produce per se an SCE increase, were immediately post-treated with these inhibitors of uracil-DNA glycosylase, a significant increase in SCE levels was obtained. Moreover, SCE levels in irradiated cells dropped to control level when a short holding time elapsed between exposure to VL and the beginning of post-treatment with the inhibitor. Thus, our results showed that inhibitors of uracil-DNA glycosylase enhanced SCE levels in cells with unifilarly BrdU-substituted DNA exposed to visible light; and indicated the existence of a very rapid repair of SCE-inducing lesions produced by visible light irradiation of cells with unifilarly BrdU-containing DNA.

  16. 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.

  17. EIAV vector-mediated delivery of endostatin or angiostatin inhibits angiogenesis and vascular hyperpermeability in experimental CNV.

    PubMed

    Balaggan, K S; Binley, K; Esapa, M; MacLaren, R E; Iqball, S; Duran, Y; Pearson, R A; Kan, O; Barker, S E; Smith, A J; Bainbridge, J W B; Naylor, S; Ali, R R

    2006-08-01

    We evaluated the efficacy of equine infectious anaemia virus (EIAV)-based lentiviral vectors encoding endostatin (EIAV.endostatin) or angiostatin (EIAV.angiostatin) in inhibiting angiogenesis and vascular hyperpermeability in the laser-induced model of choroidal neovascularisation (CNV). Equine infectious anaemia virus.endostatin, EIAV.angiostatin or control (EIAV.null) vectors were administered into the subretinal space of C57Bl/6J mice. Two weeks after laser injury CNV areas and the degree of vascular hyperpermeability were measured by image analysis of in vivo fluorescein angiograms. Compared with EIAV.null-injected eyes, EIAV.endostatin resulted in a 59.5% (P<0.001) reduction in CNV area and a reduction in hyperpermeability of 25.6% (P<0.05). Equine infectious anaemia virus.angiostatin resulted in a 50.0% (P<0.05) reduction in CNV area and a 23.9% (P<0.05) reduction in hyperpermeability. Equine infectious anaemia virus.endostatin, but not EIAV.angiostatin significantly augmented the frequency of apoptosis within the induced CNV as compared with injected controls. TdT-dUTP terminal nick end labeling analysis 5 weeks post-injection, and histological and retinal flatmount analysis 12 months post-injection revealed no evidence of vector- or transgene expression-related deleterious effects on neurosensory retinal cells, or mature retinal vasculature in non-lasered eyes. Highly expressing EIAV-based vectors encoding endostatin or angiostatin effectively control angiogenesis and hyperpermeability in experimental CNV without long-term deleterious effects, supporting the use of such a strategy in the management of patients with exudative age-related macular degeneration.

  18. 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

  19. 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.

  20. Coenzyme Q10 Ameliorates Ultraviolet B Irradiation Induced Cell Death Through Inhibition of Mitochondrial Intrinsic Cell Death Pathway

    PubMed Central

    Jing, Li; Kumari, Santosh; Mendelev, Natalia; Li, P. Andy

    2011-01-01

    Ultraviolet B (UVB) induces cell death by increasing free radical production, activating apoptotic cell death pathways and depolarizing mitochondrial membrane potential. Coenzyme Q10 (CoQ10), an essential cofactor in the mitochondrial electron transport chain, serves as a potent antioxidant in the mitochondria. The aim of the present study is to establish whether CoQ10 is capable of protecting neuronal cells against UVB-induced damage. Murine hippocampal HT22 cells were treated with 0.01, 0.1 or 1 μM of CoQ10 3 or 24 h prior to the cells being exposed to UVB irradiation. The CoQ10 concentrations were maintained during irradiation and 24 h post-UVB. Cell viability was assessed by counting viable cells and MTT conversion assay. Superoxide production and mitochondrial membrane potential were measured using fluorescent probes. Levels of cleaved caspase-9, caspase-3, and apoptosis-inducing factor (AIF) were detected using immunocytochemistry and Western blotting. The results showed that UVB irradiation decreased cell viability and such damaging effect was associated with increased superoxide production, mitochondrial depolarization, and activation of caspase-9 and caspase-3. Treatment with CoQ10 at three different concentrations started 24 h before UVB exposure significantly increased the cell viability. The protective effect of CoQ10 was associated with reduction in superoxide production, normalization of mitochondrial membrane potential and inhibition of caspase-9 and caspase-3 activation. It is concluded that the neuroprotective effect of CoQ10 results from inhibiting oxidative stress and blocking caspase-3 dependent cell death pathway. PMID:22174665

  1. Alk1 and Alk5 inhibition by Nrp1 controls vascular sprouting downstream of Notch

    PubMed Central

    Aspalter, Irene Maria; Gordon, Emma; Dubrac, Alexandre; Ragab, Anan; Narloch, Jarek; Vizán, Pedro; Geudens, Ilse; Collins, Russell Thomas; Franco, Claudio Areias; Abrahams, Cristina Luna; Thurston, Gavin; Fruttiger, Marcus; Rosewell, Ian; Eichmann, Anne; Gerhardt, Holger

    2015-01-01

    Sprouting angiogenesis drives blood vessel growth in healthy and diseased tissues. Vegf and Dll4/Notch signalling cooperate in a negative feedback loop that specifies endothelial tip and stalk cells to ensure adequate vessel branching and function. Current concepts posit that endothelial cells default to the tip-cell phenotype when Notch is inactive. Here we identify instead that the stalk-cell phenotype needs to be actively repressed to allow tip-cell formation. We show this is a key endothelial function of neuropilin-1 (Nrp1), which suppresses the stalk-cell phenotype by limiting Smad2/3 activation through Alk1 and Alk5. Notch downregulates Nrp1, thus relieving the inhibition of Alk1 and Alk5, thereby driving stalk-cell behaviour. Conceptually, our work shows that the heterogeneity between neighbouring endothelial cells established by the lateral feedback loop of Dll4/Notch utilizes Nrp1 levels as the pivot, which in turn establishes differential responsiveness to TGF-β/BMP signalling. PMID:26081042

  2. Hair follicle-derived blood vessels vascularize tumors in skin and are inhibited by Doxorubicin.

    PubMed

    Amoh, Yasuyuki; Li, Lingna; Yang, Meng; Jiang, Ping; Moossa, Abdool R; Katsuoka, Kensei; Hoffman, Robert M

    2005-03-15

    We have recently shown that the neural-stem cell marker nestin is expressed in hair follicle stem cells and the blood vessel network interconnecting hair follicles in the skin of transgenic mice with nestin regulatory element-driven green fluorescent protein (ND-GFP). The hair follicles were shown to give rise to the nestin-expressing blood vessels in the skin. In the present study, we visualized tumor angiogenesis by dual-color fluorescence imaging in ND-GFP transgenic mice after transplantation of the murine melanoma cell line B16F10 expressing red fluorescent protein. ND-GFP was highly expressed in proliferating endothelial cells and nascent blood vessels in the growing tumor. Results of immunohistochemical staining showed that the blood vessel-specific antigen CD31 was expressed in ND-GFP-expressing nascent blood vessels. ND-GFP expression was diminished in the vessels with increased blood flow. Progressive angiogenesis during tumor growth was readily visualized during tumor growth by GFP expression. Doxorubicin inhibited the nascent tumor angiogenesis as well as tumor growth in the ND-GFP mice transplanted with B16F10-RFP. This model is useful for direct visualization of tumor angiogenesis and evaluation of angiogenic inhibitors.

  3. Roscovitine attenuates intimal hyperplasia via inhibiting NF-κB and STAT3 activation induced by TNF-α in vascular smooth muscle cells.

    PubMed

    He, Ming; Wang, Chao; Sun, Jia-Huan; Liu, Yu; Wang, Hong; Zhao, Jing-Shan; Li, Yun-Feng; Chang, Hong; Hou, Jian-Ming; Song, Jun-Na; Li, Ai-Ying; Ji, En-Sheng

    2017-08-01

    Roscovitine is a selective CDK inhibitor originally designed as anti-cancer agent, which has also been shown to inhibit proliferation in vascular smooth muscle cells (VSMCs). However, its effect on vascular remodeling and its mechanism of action remain unknown. In our study, we created a new intimal hyperplasia model in male Sprague-Dawley rats by trypsin digestion method, which cause to vascular injury as well as the model of rat carotid balloon angioplasty. Roscovitine administration led to a significant reduction in neointimal formation and VSMCs proliferation after injury in rats. Western blot analysis revealed that, in response to vascular injury, TNF-α stimulation induced p65 and STAT3 phosphorylation and promoted translocation of these molecules into the nucleus. p65 can physically associate with STAT3 and bind to TNF-α-regulated target promoters, such as MCP-1 and ICAM-1, to initiate gene transcription. Roscovitine can interrupt activation of NF-κB and reduce expression of TNF-α-induced proinflammatory gene, thus inhibiting intimal hyperplasia. These findings provide a novel mechanism to explain the roscovitine-mediated inhibition of intimal hyperplasia induced by proinflammatory pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Water-Filtered Infrared A Irradiation in Combination with Visible Light Inhibits Acute Chlamydial Infection

    PubMed Central

    Marti, Hanna; Koschwanez, Maria; Pesch, Theresa; Blenn, Christian; Borel, Nicole

    2014-01-01

    New therapeutic strategies are needed to overcome drawbacks in treatment of infections with intracellular bacteria. Chlamydiaceae are Gram-negative bacteria implicated in acute and chronic diseases such as abortion in animals and trachoma in humans. Water-filtered infrared A (wIRA) is short wavelength infrared radiation with a spectrum ranging from 780 to 1400 nm. In clinical settings, wIRA alone and in combination with visible light (VIS) has proven its efficacy in acute and chronic wound healing processes. This is the first study to demonstrate that wIRA irradiation combined with VIS (wIRA/VIS) diminishes recovery of infectious elementary bodies (EBs) of both intra- and extracellular Chlamydia (C.) in two different cell lines (Vero, HeLa) regardless of the chlamydial strain (C. pecorum, C. trachomatis serovar E) as shown by indirect immunofluorescence and titration by subpassage. Moreover, a single exposure to wIRA/VIS at 40 hours post infection (hpi) led to a significant reduction of C. pecorum inclusion frequency in Vero cells and C. trachomatis in HeLa cells, respectively. A triple dose of irradiation (24, 36, 40 hpi) during the course of C. trachomatis infection further reduced chlamydial inclusion frequency in HeLa cells without inducing the chlamydial persistence/stress response, as ascertained by electron microscopy. Irradiation of host cells (HeLa, Vero) neither affected cell viability nor induced any molecular markers of cytotoxicity as investigated by Alamar blue assay and Western blot analysis. Chlamydial infection, irradiation, and the combination of both showed a similar release pattern of a subset of pro-inflammatory cytokines (MIF/GIF, Serpin E1, RANTES, IL-6, IL-8) and chemokines (IL-16, IP-10, ENA-78, MIG, MIP-1α/β) from host cells. Initial investigation into the mechanism indicated possible thermal effects on Chlamydia due to irradiation. In summary, we demonstrate a non-chemical reduction of chlamydial infection using the combination of water

  5. Water-filtered infrared a irradiation in combination with visible light inhibits acute chlamydial infection.

    PubMed

    Marti, Hanna; Koschwanez, Maria; Pesch, Theresa; Blenn, Christian; Borel, Nicole

    2014-01-01

    New therapeutic strategies are needed to overcome drawbacks in treatment of infections with intracellular bacteria. Chlamydiaceae are Gram-negative bacteria implicated in acute and chronic diseases such as abortion in animals and trachoma in humans. Water-filtered infrared A (wIRA) is short wavelength infrared radiation with a spectrum ranging from 780 to 1400 nm. In clinical settings, wIRA alone and in combination with visible light (VIS) has proven its efficacy in acute and chronic wound healing processes. This is the first study to demonstrate that wIRA irradiation combined with VIS (wIRA/VIS) diminishes recovery of infectious elementary bodies (EBs) of both intra- and extracellular Chlamydia (C.) in two different cell lines (Vero, HeLa) regardless of the chlamydial strain (C. pecorum, C. trachomatis serovar E) as shown by indirect immunofluorescence and titration by subpassage. Moreover, a single exposure to wIRA/VIS at 40 hours post infection (hpi) led to a significant reduction of C. pecorum inclusion frequency in Vero cells and C. trachomatis in HeLa cells, respectively. A triple dose of irradiation (24, 36, 40 hpi) during the course of C. trachomatis infection further reduced chlamydial inclusion frequency in HeLa cells without inducing the chlamydial persistence/stress response, as ascertained by electron microscopy. Irradiation of host cells (HeLa, Vero) neither affected cell viability nor induced any molecular markers of cytotoxicity as investigated by Alamar blue assay and Western blot analysis. Chlamydial infection, irradiation, and the combination of both showed a similar release pattern of a subset of pro-inflammatory cytokines (MIF/GIF, Serpin E1, RANTES, IL-6, IL-8) and chemokines (IL-16, IP-10, ENA-78, MIG, MIP-1α/β) from host cells. Initial investigation into the mechanism indicated possible thermal effects on Chlamydia due to irradiation. In summary, we demonstrate a non-chemical reduction of chlamydial infection using the combination of water

  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. Carbohydrate ingestion induces sex-specific cardiac vagal inhibition, but not vascular sympathetic modulation, in healthy older women.

    PubMed

    Cao, Lei; Graham, Stuart L; Pilowsky, Paul M

    2016-07-01

    The role of vagal function in cardiovascular risk in older women remains unclear. Autonomic modulation following carbohydrate ingestion (CI) and postural stress (PS) were investigated in 14 healthy men and 21 age-matched postmenopausal women (age: 65.0 ± 2.1 vs. 64.1 ± 1.6 years), with normal and comparable insulin sensitivity. Continuous noninvasive finger arterial pressure and ECG were recorded in the lying and the standing positions before and after ingestion of a carbohydrate-rich meal (600 kcal, carbohydrate 78%, protein 13%, and fat 8%). Low-frequency (LF, 0.04-0.15 Hz) and high-frequency (HF, 0.15-0.4 Hz) components (ms(2)) of heart rate variability (HRV), low-frequency power (mmHg(2)) of systolic blood pressure variability (SBP LF power), and the sequence method for spontaneous baroreflex sensitivity (BRS, ms/mmHg) were used to quantify autonomic modulation. In response to CI and PS, mean arterial pressure maintained stable, and heart rate increased in women and men in the lying and standing positions. Following CI (60, 90, and 120 min postprandially) in the standing position, SBP LF power increased by 40% in men (P = 0.02), with unchanged HRV parameters; in contrast, in women, HRV HF power halved (P = 0.02), with unaltered SBP LF power. During PS before and after CI, similar magnitude of SBP LF power, HRV, and BRS changes was observed in men and women. In conclusion, CI induces sex-specific vascular sympathetic activation in healthy older men, and cardiac vagal inhibition in healthy older women; this CI-mediated efferent vagal inhibition may suggest differential cardiovascular risk factors in women, irrespective of insulin resistance, and impairment of autonomic control. Copyright © 2016 the American Physiological Society.

  8. miRNA‑504 inhibits p53‑dependent vascular smooth muscle cell apoptosis and may prevent aneurysm formation.

    PubMed

    Cao, Xue; Cai, Zhenguo; Liu, Junyan; Zhao, Yanru; Wang, Xin; Li, Xueqi; Xia, Hongyuan

    2017-09-01

    Abdominal aortic aneurysm (AAA) is a common disease that is associated with the proliferation and apoptosis of vascular smooth muscle cells (VSMCs). VSMCs are regulated by microRNAs (miRNA). The aim of the present study was to identify miRNA sequences that regulate aortic SMCs during AAA. miRNA‑504 was identified using a miRNA PCR array and by reverse transcription‑quantitative polymerase chain reaction analysis, and its expression levels were observed to be downregulated in the aortic cells derived from patients with AAA when compared with controls. Transfection of SMCs with pMSCV‑miRNA‑504 vector was performed, and cell proliferation and the expression levels of proliferating cell nuclear antigen (PCNA), replication factor C subunit 4 (RFC4), B‑cell lymphoma‑2 (Bcl‑2) and caspase‑3/9 were measured by western blotting. The mechanisms underlying the effects of miRNA‑504 was then analyzed. The results demonstrated that overexpression of miRNA‑504 significantly upregulated the expression levels of PCNA, RFC4 and Bcl‑2, while caspase‑3/9 expression was significantly inhibited when compared with non‑targeting controls. In addition, miRNA‑504 overexpression was observed to promote the proliferation of SMCs. The expression level of the tumor suppressor, p53, which is known to be a direct target of miRNA‑504, was inhibited following transfection of SMCs with pMSCV‑miRNA‑504. In addition, the expression of the downstream targets of p53, p21 and Bcl‑like protein‑4, were significantly reduced following overexpression of miRNA‑504. These results revealed the anti‑apoptotic role of miRNA‑504 in SMCs derived from patients with AAA via direct targeting of p53.

  9. 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

  10. Niaspan inhibits diabetic retinopathy-induced vascular inflammation by downregulating the tumor necrosis factor-α pathway

    PubMed Central

    Wang, Yang; Meng, Xiangda; Yan, Hua

    2017-01-01

    Diabetic retinopathy (DR) is a serious microvascular complication of diabetes and a major cause of blindness in the developing world. Early DR is characterized by vascular neuroinflammation, cell apoptosis and breakdown of the blood-retinal barrier (BRB). However, optimal treatment options and associated mechanisms remain unclear. Niaspan, which is widely used in the prevention and treatment of hyperlipidemia-associated diseases, has been reported to inhibit inflammation. However, the effects of Niaspan and the mechanisms underlying the anti-inflammatory effects of Niaspan on DR have yet to be reported. The present study aimed to investigate the anti-inflammatory effects and mechanisms of Niaspan in a rat model of DR. Rats with DR exhibited a significant increase in BRB breakdown, retinal apoptosis, and tumor necrosis factor-α (TNF-α) and nuclear factor-κB (NF-κB) expression. In addition, the expression levels of inducible nitric oxide synthase (iNOS) and intercellular cell adhesion molecule-1 (ICAM-1) were increased in the retinas of DR rats compared with in the normal control group. In conclusion, treatment with Niaspan significantly improved clinical and histopathological outcomes; decreased the expression levels of TNF-α, NF-κB, iNOS and ICAM-1; and decreased apoptosis and BRB breakdown, as compared with in the retinas of DR rats. The present study is the first, to the best of our knowledge, to demonstrate that Niaspan treatment ameliorates DR by inhibiting inflammation, and also suggests that the TNF-α pathway may contribute to the beneficial effects of Niaspan treatment. PMID:28138697

  11. 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

  12. Inhibition of SRF/myocardin reduces aortic stiffness by targeting vascular smooth muscle cell stiffening in hypertension

    PubMed Central

    Zhou, Ning; Lee, Jia-Jye; Stoll, Shaunrick; Ma, Ben; Wiener, Robert; Wang, Charles; Costa, Kevin D.; Qiu, Hongyu

    2017-01-01

    Aims Increased aortic stiffness is a fundamental manifestation of hypertension. However, the molecular mechanisms involved remain largely unknown. We tested the hypothesis that abnormal intrinsic vascular smooth muscle cell (VSMC) mechanical properties in large arteries, but not in distal arteries, contribute to the pathogenesis of aortic stiffening in hypertension, mediated by the serum response factor (SRF)/myocardin signalling pathway. Methods and results Four month old male spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were studied. Using atomic force microscopy, significant VSMC stiffening was observed in the large conducting aorta compared with the distal arteries in SHR (P < 0.001), however, this regional variation was not observed in WKY rats (P > 0.4). The increase of VSMC stiffness was accompanied by a parallel increase in the expression of SRF by 9.8-fold and of myocardin by 10.5-fold in thoracic aortic VSMCs from SHR vs. WKY rats, resulting in a significant increase of downstream stiffness-associated genes (all, P < 0.01 vs. WKY). Inhibition of SRF/myocardin expression selectively attenuated aortic VSMC stiffening, and normalized downstream targets in VSMCs isolated from SHR but not from WKY rats. In vivo, 2 weeks of treatment with SRF/myocardin inhibitor delivered by subcutaneous osmotic minipump significantly reduced aortic stiffness and then blood pressure in SHR but not in WKY rats, although concomitant changes in aortic wall remodelling were not detected during this time frame. Conclusions SRF/myocardin pathway acts as a pivotal mediator of aortic VSMC mechanical properties and plays a central role in the pathological aortic stiffening in hypertension. Attenuation of aortic VSMC stiffening by pharmacological inhibition of SRF/myocardin signalling presents a novel therapeutic strategy for the treatment of hypertension by targeting the cellular contributors to aortic stiffness. PMID:28003268

  13. Lean and Obese Coronary Perivascular Adipose Tissue Impairs Vasodilation via Differential Inhibition of Vascular Smooth Muscle K+ Channels.

    PubMed

    Noblet, Jillian N; Owen, Meredith K; Goodwill, Adam G; Sassoon, Daniel J; Tune, Johnathan D

    2015-06-01

    The effects of coronary perivascular adipose tissue (PVAT) on vasomotor tone are influenced by an obese phenotype and are distinct from other adipose tissue depots. The purpose of this investigation was to examine the effects of lean and obese coronary PVAT on end-effector mechanisms of coronary vasodilation and to identify potential factors involved. Hematoxylin and eosin staining revealed similarities in coronary perivascular adipocyte size between lean and obese Ossabaw swine. Isometric tension studies of isolated coronary arteries from Ossabaw swine revealed that factors derived from lean and obese coronary PVAT attenuated vasodilation to adenosine. Lean coronary PVAT inhibited K(Ca) and KV7, but not KATP channel-mediated dilation in lean arteries. In the absence of PVAT, vasodilation to K(Ca) and KV7 channel activation was impaired in obese arteries relative to lean arteries. Obese PVAT had no effect on K(Ca) or KV7 channel-mediated dilation in obese arteries. In contrast, obese PVAT inhibited KATP channel-mediated dilation in both lean and obese arteries. The differential effects of obese versus lean PVAT were not associated with changes in either coronary KV7 or K(ATP) channel expression. Incubation with calpastatin attenuated coronary vasodilation to adenosine in lean but not in obese arteries. These findings indicate that lean and obese coronary PVAT attenuates vasodilation via inhibitory effects on vascular smooth muscle K(+) channels and that alterations in specific factors such as calpastatin are capable of contributing to the initiation or progression of smooth muscle dysfunction in obesity. © 2015 American Heart Association, Inc.

  14. 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

  15. Leptin Inhibits the Proliferation of Vascular Smooth Muscle Cells Induced by Angiotensin II through Nitric Oxide-Dependent Mechanisms

    PubMed Central

    Rodríguez, Amaia; Gómez-Ambrosi, Javier; Catalán, Victoria; Fortuño, Ana; Frühbeck, Gema

    2010-01-01

    Objective. This study was designed to investigate whether leptin modifies angiotensin (Ang) II-induced proliferation of aortic vascular smooth muscle cells (VSMCs) from 10-week-old male Wistar and spontaneously hypertensive rats (SHR), and the possible role of nitric oxide (NO). Methods. NO and NO synthase (NOS) activity were assessed by the Griess and 3H-arginine/citrulline conversion assays, respectively. Inducible NOS (iNOS) and NADPH oxidase subutnit Nox2 expression was determined by Western-blot. The proliferative responses to Ang II were evaluated through enzymatic methods. Results. Leptin inhibited the Ang II-induced proliferative response of VSMCs from control rats. This inhibitory effect of leptin was abolished by NOS inhibitor, NMMA, and iNOS selective inhibitor, L-NIL, and was not observed in leptin receptor-deficient fa/fa rats. SHR showed increased serum leptin concentrations and lipid peroxidation. Despite a similar leptin-induced iNOS up-regulation, VSMCs from SHR showed an impaired NOS activity and NO production induced by leptin, and an increased basal Nox2 expression. The inhibitory effect of leptin on Ang II-induced VSMC proliferation was attenuated. Conclusion. Leptin blocks the proliferative response to Ang II through NO-dependent mechanisms. The attenuation of this inhibitory effect of leptin in spontaneous hypertension appears to be due to a reduced NO bioavailability in VSMCs. PMID:20592755

  16. Glycosaminoglycan sulodexide inhibition of MMP-9 gelatinase secretion and activity: possible pharmacological role against collagen degradation in vascular chronic diseases.

    PubMed

    Mannello, Ferdinando; Medda, Virginia; Ligi, Daniela; Raffetto, Joseph D

    2013-05-01

    We evaluated the effects of the glycosaminoglycan sulodexide (SDX; antithrombotic/profibrinolytic drug) on the activity and release of matrix metalloproteinases (MMPs) in human blood. This was a prospective non-randomized study, analyzing by zymography and ELISA the in vitro effects of SDX on pro-enzyme, complexed, and active MMP forms in plasma and serum from 60 healthy donors, and in U-937 leukemia cell line. The levels and zymographic profile of MMP-2 did not show significant changes among samples and during SDX treatments. However, pro- and complexed forms of MMP-9 were strongly affected by SDX treatment (P<0.001), with significant decrease of MMP-9 secretion from white blood cells in a dose-dependent fashion (P<0.0001), without any displacement of MMP prodomains. The mechanism of reduced release of MMP-9 forms from leukocytes and inhibition of proteolytic activity due to SDX treatment may support the hypothesis that drugs based upon inhibitors of MMP-9 activity may provide a therapeutic tool for the underlying pathological destruction of extracellular matrix, and offering novel pharmacologic applications for chronic inflammatory vascular diseases, including varicose vein and chronic venous diseases associated with enhanced MMP activation in blood and limbs.

  17. 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.

  18. Pegylated G-CSF Inhibits Blood Cell Depletion, Increases Platelets, Blocks Splenomegaly, and Improves Survival after Whole-Body Ionizing Irradiation but Not after Irradiation Combined with Burn

    PubMed Central

    Kiang, Juliann G.; Zhai, Min; Liao, Pei-Jyun; Bolduc, David L.; Elliott, Thomas B.; Gorbunov, Nikolai V.

    2014-01-01

    Exposure to ionizing radiation alone (radiation injury, RI) or combined with traumatic tissue injury (radiation combined injury, CI) is a crucial life-threatening factor in nuclear and radiological accidents. As demonstrated in animal models, CI results in greater mortality than RI. In our laboratory, we found that B6D2F1/J female mice exposed to 60Co-γ-photon radiation followed by 15% total-body-surface-area skin burns experienced an increment of 18% higher mortality over a 30-day observation period compared to irradiation alone; that was accompanied by severe cytopenia, thrombopenia, erythropenia, and anemia. At the 30th day after injury, neutrophils, lymphocytes, and platelets still remained very low in surviving RI and CI mice. In contrast, their RBC, hemoglobin, and hematocrit were similar to basal levels. Comparing CI and RI mice, only RI induced splenomegaly. Both RI and CI resulted in bone marrow cell depletion. It was observed that only the RI mice treated with pegylated G-CSF after RI resulted in 100% survival over the 30-day period, and pegylated G-CSF mitigated RI-induced body-weight loss and depletion of WBC and platelets. Peg-G-CSF treatment sustained RBC balance, hemoglobin levels, and hematocrits and inhibited splenomegaly after RI. The results suggest that pegylated G-CSF effectively sustained animal survival by mitigating radiation-induced cytopenia, thrombopenia, erythropenia, and anemia. PMID:24738019

  19. The PPARalpha Agonist Fenofibrate Preserves Hippocampal Neurogenesis and Inhibits Microglial Activation After Whole-Brain Irradiation

    SciTech Connect

    Ramanan, Sriram; Kooshki, Mitra; Zhao Weiling; Hsu, F.-C.; Riddle, David R.; Robbins, Mike E.

    2009-11-01

    Purpose: Whole-brain irradiation (WBI) leads to cognitive impairment months to years after radiation. Numerous studies suggest that decreased hippocampal neurogenesis and microglial activation are involved in the pathogenesis of WBI-induced brain injury. The goal of this study was to investigate whether administration of the peroxisomal proliferator-activated receptor (PPAR) alpha agonist fenofibrate would prevent the detrimental effect of WBI on hippocampal neurogenesis. Methods and Materials: For this study, 129S1/SvImJ wild-type and PPARalpha knockout mice that were fed either regular or 0.2% wt/wt fenofibrate-containing chow received either sham irradiation or WBI (10-Gy single dose of {sup 137}Cs gamma-rays). Mice were injected intraperitoneally with bromodeoxyuridine to label the surviving cells at 1 month after WBI, and the newborn neurons were counted at 2 months after WBI by use of bromodeoxyuridine/neuronal nuclei double immunofluorescence. Proliferation in the subgranular zone and microglial activation were measured at 1 week and 2 months after WBI by use of Ki-67 and CD68 immunohistochemistry, respectively. Results: Whole-brain irradiation led to a significant decrease in the number of newborn hippocampal neurons 2 months after it was performed. Fenofibrate prevented this decrease by promoting the survival of newborn cells in the dentate gyrus. In addition, fenofibrate treatment was associated with decreased microglial activation in the dentate gyrus after WBI. The neuroprotective effects of fenofibrate were abolished in the knockout mice, indicating a PPARalpha-dependent mechanism or mechanisms. Conclusions: These data highlight a novel role for PPARalpha ligands in improving neurogenesis after WBI and offer the promise of improving the quality of life for brain cancer patients receiving radiotherapy.

  20. Radiosensitization by PARP inhibition to proton beam irradiation in cancer cells

    SciTech Connect

    Hirai, Takahisa; Saito, Soichiro; Fujimori, Hiroaki; Matsushita, Keiichiro; Nishio, Teiji; Okayasu, Ryuichi; Masutani, Mitsuko

    2016-09-09

    The poly(ADP-ribose) polymerase (PARP)-1 regulates DNA damage responses and promotes base excision repair. PARP inhibitors have been shown to enhance the cytotoxicity of ionizing radiation in various cancer cells and animal models. We have demonstrated that the PARP inhibitor (PARPi) AZD2281 is also an effective radiosensitizer for carbon-ion radiation; thus, we speculated that the PARPi could be applied to a wide therapeutic range of linear energy transfer (LET) radiation as a radiosensitizer. Institutes for biological experiments using proton beam are limited worldwide. This study was performed as a cooperative research at heavy ion medical accelerator in Chiba (HIMAC) in National Institute of Radiological Sciences. HIMAC can generate various ion beams; this enabled us to compare the radiosensitization effect of the PARPi on cells subjected to proton and carbon-ion beams from the same beam line. After physical optimization of proton beam irradiation, the radiosensitization effect of the PARPi was assessed in the human lung cancer cell line, A549, and the pancreatic cancer cell line, MIA PaCa-2. The effect of the PARPi, AZD2281, on radiosensitization to Bragg peak was more significant than that to entrance region. The PARPi increased the number of phosphorylated H2AX (γ-H2AX) foci and enhanced G2/M arrest after proton beam irradiation. This result supports our hypothesis that a PARPi could be applied to a wide therapeutic range of LET radiation by blocking the DNA repair response. - Highlights: • Effective radiosensitizers for particle radiation therapy have not been reported. • PARP inhibitor treatment radiosensitized after proton beam irradiation. • The sensitization at Bragg peak was greater than that at entrance region. • DSB induction and G2/M arrest is involved in the sensitization mechanism.

  1. Taxifolin inhibits amyloid-β oligomer formation and fully restores vascular integrity and memory in cerebral amyloid angiopathy.

    PubMed

    Saito, Satoshi; Yamamoto, Yumi; Maki, Takakuni; Hattori, Yorito; Ito, Hideki; Mizuno, Katsuhiko; Harada-Shiba, Mariko; Kalaria, Raj N; Fukushima, Masanori; Takahashi, Ryosuke; Ihara, Masafumi

    2017-04-04

    Cerebral amyloid angiopathy (CAA) induces various forms of cerebral infarcts and hemorrhages from vascular amyloid-β accumulation, resulting in acceleration of cognitive impairment, which is currently untreatable. Soluble amyloid-β protein likely impairs cerebrovascular integrity as well as cognitive function in early stage Alzheimer's disease. Taxifolin, a flavonol with strong anti-oxidative and anti-glycation activities, has been reported to disassemble amyloid-β in vitro but the in vivo relevance remains unknown. Here, we investigated whether taxifolin has therapeutic potential in attenuating CAA, hypothesizing that inhibiting amyloid-β assembly may facilitate its clearance through several elimination pathways. Vehicle- or taxifolin-treated Tg-SwDI mice (commonly used to model CAA) were used in this investigation. Cognitive and cerebrovascular function, as well as the solubility and oligomerization of brain amyloid-β proteins, were investigated. Spatial reference memory was assessed by water maze test. Cerebral blood flow was measured with laser speckle flowmetry and cerebrovascular reactivity evaluated by monitoring cerebral blood flow changes in response to hypercapnia. Significantly reduced cerebrovascular pan-amyloid-β and amyloid-β1-40 accumulation was found in taxifolin-treated Tg-SwDI mice compared to vehicle-treated counterparts (n = 5). Spatial reference memory was severely impaired in vehicle-treated Tg-SwDI mice but normalized after taxifolin treatment, with scoring similar to wild type mice (n = 10-17). Furthermore, taxifolin completely restored decreased cerebral blood flow and cerebrovascular reactivity in Tg-SwDI mice (n = 4-6). An in vitro thioflavin-T assay showed taxifolin treatment resulted in efficient inhibition of amyloid-β1-40 assembly. In addition, a filter trap assay and ELISA showed Tg-SwDI mouse brain homogenates exhibited significantly reduced levels of amyloid-β oligomers in vivo after taxifolin treatment (n

  2. 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

  3. Synergistic effect of fluoride and laser irradiation for the inhibition of the demineralization of dental enamel

    NASA Astrophysics Data System (ADS)

    Lee, Raymond; Chan, Kenneth H.; Jew, Jamison; Simon, Jacob C.; Fried, Daniel

    2017-02-01

    Both laser irradiation and fluoride treatment alone are known to provide increased resistance to acid dissolution. CO2 lasers tuned to a wavelength of 9.3 μm can be used to efficiently convert the carbonated hydroxyapatite of enamel to a much more acid resistant purer phase hydroxyapatite (HAP). Further studies have shown that fluoride application to HAP yields fluoroapatite (FAP) which is even more resistant against acid dissolution. Previous studies show that CO2 lasers and fluoride treatments interact synergistically to provide significantly higher protection than either method alone, but the mechanism of interaction has not been elucidated. We recently observed the formation of microcracks or a "crazed" zone in the irradiated region that is resistant to demineralization using high-resolution microscopy. The microcracks are formed due to the slight contraction of enamel due to transformation of carbonated hydroxyapatite to the more acid resistant pure phase hydroxyapatite (HAP) that has a smaller lattice. In this study, we test the hypothesis that these small cracks will provide greater adhesion for topical fluoride for greater protection against acid demineralization.

  4. Synergistic effect of fluoride and laser irradiation for the inhibition of the demineralization of dental enamel.

    PubMed

    Lee, Raymond; Chan, Kenneth H; Jew, Jamison; Simon, Jacob C; Fried, Daniel

    2017-01-28

    Both laser irradiation and fluoride treatment alone are known to provide increased resistance to acid dissolution. CO2 lasers tuned to a wavelength of 9.3 μm can be used to efficiently convert the carbonated hydroxyapatite of enamel to a much more acid resistant purer phase hydroxyapatite (HAP). Further studies have shown that fluoride application to HAP yields fluoroapatite (FAP) which is even more resistant against acid dissolution. Previous studies show that CO2 lasers and fluoride treatments interact synergistically to provide significantly higher protection than either method alone, but the mechanism of interaction has not been elucidated. We recently observed the formation of microcracks or a "crazed" zone in the irradiated region that is resistant to demineralization using high-resolution microscopy. The microcracks are formed due to the slight contraction of enamel due to transformation of carbonated hydroxyapatite to the more acid resistant pure phase hydroxyapatite (HAP) that has a smaller lattice. In this study, we test the hypothesis that these small cracks will provide greater adhesion for topical fluoride for greater protection against acid demineralization.

  5. Extract from Periostracum cicadae Inhibits Oxidative Stress and Inflammation Induced by Ultraviolet B Irradiation on HaCaT Keratinocytes

    PubMed Central

    Tsen, Jen-Horng; Yen, Hsuan; Yang, Ting-Ya

    2017-01-01

    Periostracum cicadae is widely used for the treatment of skin diseases such as eczema, pruritus, and itching. The current study sought to evaluate the effect of P. cicadae extract on ultraviolet B (UVB) irradiation and identify the mechanisms involved. Photodamage-protective activity of P. cicadae extracts against oxidative challenge was screened using HaCaT keratinocytes. P. cicadae extracts did not affect cell viability but decreased reactive oxygen species (ROS) production. The extract attenuates the expression of interleukin-6 (IL-6), matrix metalloproteinase-2 (MMP-2), and MMP-9 in UVB-treated HaCaT cells. Also, P. cicadae abrogated UVB-induced activation of NF-κB, p53, and activator protein-1 (AP-1). The downmodulation of IL-6 by P. cicadae was inhibited by the p38 inhibitor (SB203580) or JNK inhibitor (SP600125). Moreover, the extract attenuated the expression of NF-κB and induced thrombomodulin in keratinocytes and thereby effectively downregulated inflammatory responses in the skin. The nuclear accumulation and expression of NF-E2-related factor (Nrf2) were increased by P. cicadae treatment. Furthermore, treatment with P. cicadae remarkably ameliorated the skin's structural damage induced by irradiation. This study demonstrates that P. cicadae may protect skin cells against oxidative insult by modulating ROS concentration, IL-6, MMPs generation, antioxidant enzymes activity, and cell signaling pathways. PMID:28465707

  6. Overexpression of Mitofusin 2 inhibited oxidized low-density lipoprotein induced vascular smooth muscle cell proliferation and reduced atherosclerotic lesion formation in rabbit

    SciTech Connect

    Guo Yanhong; Chen Kuanghueih; Gao Wei; Li Qian; Chen Li; Wang Guisong Tang Jian

    2007-11-16

    Our previous studies have implies that Mitofusin 2 (Mfn2), which was progressively reduced in arteries from ApoE{sup -/-} mice during the development of atherosclerosis, may take part in pathogenesis of atherosclerosis. In this study, we found that overexpression of Mfn2 inhibited oxidized low-density lipoprotein or serum induced vascular smooth muscle cell proliferation by down-regulation of Akt and ERK phosphorylation. Then we investigated the in vivo role of Mfn2 on the development of atherosclerosis in rabbits using adenovirus expressing Mitofusin 2 gene (AdMfn2). By morphometric analysis we found overexpression of Mfn2 inhibited atherosclerotic lesion formation and intima/media ratio by 66.7% and 74.6%, respectively, compared with control group. These results suggest that local Mfn2 treatment suppresses the development of atherosclerosis in vivo in part by attenuating the smooth muscle cell proliferation induced by lipid deposition and vascular injury.

  7. Analysis of inhibition of DNA replication in irradiated cells using the SV40 based in vitro assay of DNA replication.

    PubMed

    Iliakis, George; Mladenov, Emil; Wang, Ya; Wang, Hong Yan

    2012-01-01

    The deleterious effects of DNA damage on DNA replication have been demonstrated in many model systems and the mechanisms of the resulting inhibition have been a research focus for at least 40 years. Moreover, recent studies have identified several major components of the S-phase checkpoint, providing a mechanistic background for understanding the basis of inhibition of the initiation and elongation steps of DNA replication after DNA damage. Yet several aspects of the underlying biochemical mechanisms remain unresolved including the characterization of the enzymatic activities involved in checkpoint activation and the coordination of this process with DNA repair. Helpful for the delineation of the mechanism of the S-phase checkpoint is the observation that factors inhibiting DNA replication in vivo can be found in active form in extracts prepared from irradiated cells, when these are tested using the simian virus 40 (SV40) assay for in vitro DNA replication. In this assay, replication of plasmid DNA carrying the minimal origin of SV40 DNA replication is achieved in vitro using cytoplasmic cell extracts and SV40 large tumor antigen (TAg) as the only noncellular protein. Here, we describe protocols developed to measure in vitro DNA replication with the purpose of analyzing its regulation after exposure to DNA damage. The procedures include the preparation of components of the in vitro DNA replication reaction including cytoplasmic extracts from cells that have sustained DNA damage. The assay provides a powerful tool for investigating the effect of distinct agents acting either by inducing lesions in the DNA, or by inhibiting the functions of checkpoint proteins. Nevertheless, the fact that several steps of DNA replication initiation are carried out in this in vitro assay by TAg and not the corresponding cellular factors, might be considered as a limitation of the approach.

  8. Cyclooxygenase pathway is involved in the vascular reactivity and inhibition of the Na+, K+-ATPase activity in the tail artery from L-NAME-treated rats.

    PubMed

    dos Santos, Leonardo; Xavier, Fabiano E; Vassallo, Dalton V; Rossoni, Luciana V

    2003-12-19

    L-NAME (LN) induces hypertension by blocking nitric oxide (NO) synthesis. It produces vascular hyperreactivity to phenylephrine (PHE) associated with a reduced vascular Na+, K+-ATPase activity. The aim of this work was to investigate whether products of the cyclooxygenase pathway are involved in alterations of vascular reactivity and Na+-pump activity in the tail artery from LN-induced hypertension rats. Four groups of rats were used: Control (CT, normotensive), LN (50 mg/kg/day, hypertensive), indomethacin (Indo-4 mg/kg/day, normotensive), and LN plus Indo (LN + Indo, partially prevented hypertension). All drugs were administered in drinking water during 7 days. In isolated rat tail vascular beds; the reactivity to PHE, acetylcholine (ACh), sodium nitroprusside (SNP), the functional activity of the Na+, K+-ATPase (K+-induced relaxation) and the modulation of PHE-induced vasoconstriction by constitutively available NO were evaluated. LN increased vascular sensitivity (pD2) and reactivity (Emax) to PHE and Indo blocked the effect of LN on Emax without changing pD2. Emax and pD2 values for ACh were reduced by LN and partially reverted by Indo. SNP-induced vasodilatation was similar in all groups. LN reduced the activity of Na+, K+-ATPase and Indo prevented LN effects. LN also abolished NO ability to modulate PHE-induced contractions. This effect was partially prevented by Indo suggesting that products from the cyclooxygenase pathway might reduce NO actions. Indo itself did not affect vascular reactivity to PHE, ACh or SNP or the Na+,K+-ATPase activity. Results suggested that products from cyclooxygenase pathway are involved in the genesis or maintenance of LN-induced hypertension, playing a role in the increased vascular reactivity, in the reduction of the endothelium-dependent relaxation and in the inhibition of the functional activity of the Na+, K+-ATPase.

  9. Sargachromenol protects against vascular inflammation by preventing TNF-α-induced monocyte adhesion to primary endothelial cells via inhibition of NF-κB activation.

    PubMed

    Gwon, Wi-Gyeong; Joung, Eun-Ji; Kwon, Mi-Sung; Lim, Su-Jin; Utsuki, Tadanobu; Kim, Hyeung-Rak

    2017-01-01

    Vascular inflammation is a key factor in the pathogenesis of atherosclerosis. The purpose of this study was to investigate the protective effects of sargachromenol (SCM) against tumor necrosis factor (TNF)-α-induced vascular inflammation. SCM decreased the expression of cell adhesion molecules, including intracellular adhesion molecule-1 and vascular cell adhesion molecule-1, in TNF-α-stimulated human umbilical vein endothelial cells (HUVECs), resulted in reduced adhesion of monocytes to HUVECs. SCM also decreased the production of monocyte chemoattractant protein-1 and matrix metalloproteinase-9 in TNF-α-induced HUVECs. Additionally, SCM inhibited activation of nuclear factor kappa B (NF-κB) induced by TNF-α through preventing the degradation of inhibitor kappa B. Moreover, SCM reduced the production of reactive oxygen species in TNF-α-treated HUVECs. Overall, SCM alleviated vascular inflammation through the regulation of NF-κB activation and through its intrinsic antioxidant activity in TNF-α-induced HUVECs. These results indicate that SCM may have potential application as a therapeutic agent against vascular inflammation.

  10. Time dependent inhibition of xanthine oxidase in irradiated solutions of folic acid, aminopterin and methotrexate

    SciTech Connect

    Robinson, K.; Pilot, T.F.; Meany, J.E. )

    1990-01-01

    The xanthine oxidase catalyzed oxidation of hypoxanthine was followed by monitoring the formation of uric acid at 290 nm. Inhibition of xanthine oxidase occurs in aqueous solutions of folic acid methotrexate and aminopterin. These compounds are known to dissociate upon exposure to ultraviolet light resulting in the formation of their respective 6-formylpteridine derivatives. The relative rates of dissociation were monitored spectrophotometrically by determining the absorbance of their 2,4-dinitrophenylhydrazine derivatives at 500 nm. When aqueous solutions of folic acid, aminopterin and methotrexate were exposed to uv light, a direct correlation was observed between the concentrations of the 6-formylpteridine derivatives existing in solution and the ability of these solutions to inhibit xanthine oxidase. The relative potency of the respective photolysis products were estimated.

  11. 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.

  12. Chronic inhibition of endoplasmic reticulum stress and inflammation prevents ischaemia-induced vascular pathology in type II diabetic mice.

    PubMed

    Amin, Ali; Choi, Soo-kyoung; Galan, Maria; Kassan, Modar; Partyka, Megan; Kadowitz, Philip; Henrion, Daniel; Trebak, Mohamed; Belmadani, Souad; Matrougui, Khalid

    2012-06-01

    Endoplasmic reticulum (ER) stress and inflammation are important mechanisms that underlie many of the serious consequences of type II diabetes. However, the role of ER stress and inflammation in impaired ischaemia-induced neovascularization in type II diabetes is unknown. We studied ischaemia-induced neovascularization in the hind-limb of 4-week-old db - /db- mice and their controls treated with or without the ER stress inhibitor (tauroursodeoxycholic acid, TUDCA, 150 mg/kg per day) and interleukin-1 receptor antagonist (anakinra, 0.5 µg/mouse per day) for 4 weeks. Blood pressure was similar in all groups of mice. Blood glucose, insulin levels, and body weight were reduced in db - /db- mice treated with TUDCA. Increased cholesterol and reduced adiponectin in db - /db- mice were restored by TUDCA and anakinra treatment. ER stress and inflammation in the ischaemic hind-limb in db - /db- mice were attenuated by TUDCA and anakinra treatment. Ischaemia-induced neovascularization and blood flow recovery were significantly reduced in db - /db- mice compared to control. Interestingly, neovascularization and blood flow recovery were restored in db - /db- mice treated with TUDCA or anakinra compared to non-treated db - /db- mice. TUDCA and anakinra enhanced eNOS-cGMP, VEGFR2, and reduced ERK1/2 MAP-kinase signalling, while endothelial progenitor cell number was similar in all groups of mice. Our findings demonstrate that the inhibition of ER stress and inflammation prevents impaired ischaemia-induced neovascularization in type II diabetic mice. Thus, ER stress and inflammation could be potential targets for a novel therapeutic approach to prevent impaired ischaemia-induced vascular pathology in type II diabetes.

  13. 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

  14. CaMKIIδ-dependent Inhibition of cAMP-response Element-binding Protein Activity in Vascular Smooth Muscle*

    PubMed Central

    Liu, Yongfeng; Sun, Li-Yan; Singer, Diane V.; Ginnan, Roman; Singer, Harold A.

    2013-01-01

    One transcription factor mediator of Ca2+-signals is cAMP response element-binding protein (CREB). CREB expression and/or activity negatively correlates with vascular smooth muscle (VSM) cell proliferation and migration. Multifunctional Ca2+/calmodulin-dependent protein kinases, including CaMKII, have been demonstrated to regulate CREB activity through both positive and negative phosphorylation events in vitro, but the function of CaMKII as a proximal regulator of CREB in intact cell systems, including VSM, is not clear. In this study, we used gain- and loss-of-function approaches to determine the function of CaMKIIδ in regulating CREB phosphorylation, localization, and activity in VSM. Overexpression of constitutively active CaMKIIδ specifically increased CREB phosphorylation on Ser142 and silencing CaMKIIδ expression by siRNA or blocking endogenous CaMKII activity with KN93 abolished thrombin- or ionomycin-induced CREB phosphorylation on Ser142 without affecting Ser133 phosphorylation. CREB-Ser142 phosphorylation correlated with transient nucleocytoplasmic translocation of CREB. Thrombin-induced CREB promoter activity, CREB binding to Sik1 and Rgs2 promoters, and Sik1/Rgs2 transcription were enhanced by a kinase-negative CaMKIIδ2 (K43A) mutant and inhibited by a constitutively active (T287D) mutant. Taken together, these studies establish negative regulation of CREB activity by endogenous CaMKIIδ-dependent CREB-Ser142 phosphorylation and suggest a potential mechanism for CaMKIIδ/CREB signaling in modulating proliferation and migration in VSM cells. PMID:24106266

  15. Growth Differentiation Factor‐15 Deficiency Inhibits Atherosclerosis Progression by Regulating Interleukin‐6–Dependent Inflammatory Response to Vascular Injury

    PubMed Central

    Bonaterra, Gabriel A.; Zügel, Stefanie; Thogersen, Joel; Walter, Sabrina A.; Haberkorn, Uwe; Strelau, Jens; Kinscherf, Ralf

    2012-01-01

    Background Growth differentiation factor (GDF)‐15 is a distant and divergent member of the transforming growth factor‐β superfamily (TGF‐β) . There is growing evidence indicating the involvement of GDF‐15 in various pathologies. Expression of GDF‐15 is induced under conditions of inflammation and increased GDF‐15 serum levels are suggested as a risk factor for cardiovascular diseases. Methods and Results We show here that GDF‐15 and proinflammatory cytokine interleukin (IL)‐6 levels are highly increased (5‐fold) in cultured oxidized low‐density lipoproteins–stimulated peritoneal macrophages derived from GDF‐15+/+/apolipoprotein (apo) E−/−, mice. Notably, IL‐6 induction on oxidized low‐density lipoproteins stimulation is completely abolished in the absence of GDF‐15. Consistent with our in vitro data GDF‐15 mRNA expression and protein levels are upregulated (2.5‐ to 6‐fold) in the atherosclerotic vessel wall of GDF‐15+/+/apoE−/− mice after a cholesterol‐enriched diet. GDF‐15 deficiency inhibits lumen stenosis (52%) and 18FDG uptake (34%) in the aortic arch despite increased serum triglyceride/cholesterol levels and elevated body weight. Immunohistomorphometric investigations of atherosclerotic lesions reveal a decreased percentage of inflammatory CD11b+ (57%) or IL‐6+, leukocytes, and apoptotic cells (74%) after 20 weeks. However, the total number of macrophages and cell density in atherosclerotic lesions of the innominate artery are increased in GDF‐15−/−/apoE−/− mice. Conclusions Our data suggest that GDF‐15 is involved in orchestrating atherosclerotic lesion progression by regulating apoptotic cell death and IL‐6–dependent inflammatory responses to vascular injury. PMID:23316317

  16. 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.