Abstract P342: Vascular Protein Oxidation and Redox Proteomics in Hypertension

Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Sofia Tsiropoulou ◽  
Augusto C Montezano ◽  
Alan Scott ◽  
Richard J Burchmore ◽  
Rhian M Touyz
Keyword(s):  
Vascular Injury ◽  
Protein Oxidation ◽  
Vascular Function ◽  
Tyrosine Phosphatase ◽  
Redox Status ◽  
Mesenteric Arteries ◽  
Ang Ii ◽  
Protein Levels ◽  
Proteomic Data ◽  
Anti Oxidant

In hypertension (HTN) mechanisms whereby protein oxidation regulates vascular function remain unclear. We hypothesise that increased ROS promote a shift of oxidative post-translational protein modifications from reversible to irreversible forms, leading to aberrant redox signalling and vascular injury. VSMC from mesenteric arteries of normotensive (WKY) and hypertensive (SHRSP) rats were stimulated with Ang II (10 -7 M) in the presence/absence of PEG-catalase (1000U/ml) or tempol (10 -5 M). Protein carbonylation was assessed by oxyblot and protein sulfenylation by DCP-Rho1 fluorescent probe. Protein tyrosine phosphatase (PTP)-oxidation, peroxiredoxin hyperoxidation (PRXSO3), γH2AX, Bcl2 levels were assessed by immunoblotting. DiGE and CyDye labelling screened for reversibly oxidised thiol proteome. Irreversible carbonylation and PRXSO3 were increased in SHRSP (fold change (FC)=1.29 and 2.77, p<0.05). Ang II-stimulation did not alter carbonylation levels. Reversible sulfenylation and thiol-proteome oxidation were reduced in SHRSP (FC=-1.18, p<0.05 and 13.6% (253 spots)). Ang II-treatment increased sulfenylation in WKY (FC=1.08, p<0.05) and SHRSP (FC=1.23, p<0.001); an effect inhibited by catalase. Reversible PTP oxidation was increased in WKY and SHRSP (FC=1.92 and 2.42, p<0.05), versus irreversible levels. Irreversible PTP oxidation tended to be higher in SHRSP. Ang II increased reversible PTP oxidation only in WKY (FC=1.27, p<0.05) and it was prevented by tempol. Ang II-stimulation increased protein levels of γH2AX (DNA damage) (FC=1.76, p<0.05) and Bcl2 (anti-apoptotic) (FC=2, p<0.05) in WKY. Proteomic data, filtered for FC>2, detected 1777 spots with 21% being differentially oxidised between WKY and SHRSP. Candidate proteins differentially oxidized between WKY and SHRSP include annexin A1 (-2.29) and galectin-1 (2.83). These results demonstrate altered redox status in HTN characterised by increased protein hyperoxidation and decreased reversible oxidation, in combination with decreased anti-oxidant capacity. Moreover, our findings identify novel candidate oxidized proteins implicated in VSMC motility, proliferation and signalling which may contribute to oxidative vascular injury in HTN.

Abstract P096: Vascular Protein Oxidation and Redox Proteomics in Human Hypertension

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Sofia Tsiropoulou ◽  
Augusto C Montezano ◽  
Alan Scott ◽  
Richard J Burchmore ◽  
Rhian M Touyz
Keyword(s):  
Vascular Injury ◽  
Protein Oxidation ◽  
Protein Tyrosine Phosphatases ◽  
Redox Status ◽  
Oxidative Modification ◽  
Fk506 Binding Protein ◽  
Proteomic Data ◽  
Irreversible Oxidation ◽  
Health And Disease ◽  
Polymerase I

Oxidative stress has been implicated in the pathophysiology of hypertension (HTN) through redox-sensitive processes that cause vascular damage. Despite recent advances in the field of vascular redox signalling in HTN, it still remains unclear exactly how ROS cause vascular injury. We hypothesise that regulation of redox-sensitive protein tyrosine phosphatases (PTP) through post-translational oxidative modification, is impaired in HTN where ROS levels are increased. Vascular smooth muscle cells (VSMC) from small arteries of normotensive (NT) and hypertensive (HT) individuals were stimulated with AngII (10-7 M) and ET-1 (10-7 M). Irreversible oxidation of proteins and PTPs was assessed by oxyblot and immunoblotting, respectively. Differential gel electrophoresis (DiGE) and CyDye thiol labelling were employed for screening of reversibly oxidised proteome. Irreversible protein oxidation was not affected by AngII or ET-1 in VSMCs from NT and HT subjects. PTP hyperoxidation tended to increase in VSMCs from NT upon stimulation with AngII (FC=2.12 at 60min) and ET-1 (FC=1.60 at 60min), whereas a similar trend was observed only after AngII treatment (FC=1.38 at 60min) in HTN (p>0.05). Proteomic data, filtered for FC>2, detected 2051 spots with 1899 (92.5%) being equally oxidised between NT and HT. In addition, oxidation of 57 (2.9%) spots was increased, while 95 (4.6%) were decreased in HT. Candidate proteins exhibiting consistent changes across three experimental replicates included β-actin (FC=-2.86), annexin A1 (-2.23), galectin-1 (-1.67), FK506 binding protein (-2.35) and polymerase I and transcript release factor (PTRF, -1.92). Stimulation with AngII altered the redox status in 2-3% of proteins, both in HT and NT. However, vimentin was the only target changing consistently across the replicates (FC=2.48). Our findings indicate that pro-hypertensive agents may not impact significantly on irreversible protein and PTP oxidation in health and disease, but may have effects on reversible oxidation. Our proteomic data, in agreement with our previous rat studies, support decreased reversible thiol oxidation in HTN. Moreover, these novel findings identify differentially oxidised proteins which may contribute to oxidative vascular injury in HTN.

Abstract P217: Nox Compartmentalization, Protein Oxidation and ER Stress in Vascular Smooth Muscle Cells in Hypertension

Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Livia L Camargo ◽  
Augusto C Montezano ◽  
Adam Harvey ◽  
Sofia Tsiropoulou ◽  
Katie Hood ◽  
...  
Keyword(s):  
Er Stress ◽  
Protein Oxidation ◽  
Vascular Function ◽  
Vascular Reactivity ◽  
Stress Proteins ◽  
Vascular Dysfunction ◽  
Mesenteric Arteries ◽  
Resistance Arteries ◽  
Post Translational Modification ◽  
Wistar Kyoto

In hypertension, activation of NADPH oxidases (Noxs) is associated with oxidative stress and vascular dysfunction. The exact role of each isoform in hypertension-associated vascular injury is still unclear. We investigated the compartmentalization of Noxs in VSMC from resistance arteries of Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR). Expression of Nox1 and Nox4 was increased in SHR cells (96.6±28.7% and 48.2±21.2% vs WKY, p<0.05), as well as basal ROS levels measured by chemiluminescence (110.2±26.4% vs WKY, p<0.05) and amplex red (105.2±33.2% vs WKY, p<0.05). Phosphorylation of unfolded protein response activators, PERK and IRE1α, and expression of ER chaperone BiP were elevated in SHR cells (p<0.05 vs WKY), indicating activation of ER stress response. Immunoblotting after organelle fractionation demonstrated that Noxs are expressed in an organelle-specific manner, with Nox1, 2 and 4 present in plasma membrane, ER and nucleus, but not in mitochondria. In SHR cells, NoxA1ds (Nox1 inhibitor, 10μM) and GKT136901 (Nox1/4 inhibitor, 10μM) decreased AngII-induced ROS levels (p<0.001 vs Ctl). Additionally, mito-tempol (mitochondrial-targeted antioxidant, 50nM) and 4-PBA (ER stress inhibitor, 1mM) decreased basal ROS levels in SHR cells (p<0.05 vs Ctl). Furthermore, oxidation of the antioxidant enzymes Peroxiredoxins (Prx) was increased in SHRSP compared to WKY (2.51±0.14 vs 0.56±0.07, p<0.001). One-dimensional isoelectric focusing revealed that cytosolic Prx2 and mitochondrial Prx3 were more oxidized in SHRSP than WKY cells. Using a biotin-tagged dimedone-based probe (DCP-Bio) we identified oxidation of ER stress proteins BiP and IRE1. To investigate the effect of protein oxidation in vascular function, vascular reactivity was evaluated in isolated mesenteric arteries. Inhibition of general oxidation (DTT 1mM; Emax: 111.7±33.1) and peroxiredoxin (Conoidin A 10nM; Emax: 116.0±7.3) reduces vascular contraction in response to noradrenalin in WKY rats (Emax: 166.6±30.2; p<0.05). These findings suggest an important role for Nox1/4 in redox-dependent organelle dysfunction and post-translational modification of proteins, processes that may play an important role in vascular dysfunction in hypertension.

Abstract 44: VEGF Inhibitor-induced Vascular Dysfunction Is Ameliorated By PARP/TRPM2 Inhibition

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Karla B Neves ◽  
Rheure Alves-lopes ◽  
Ninian Lang ◽  
Augusto C Montezano ◽  
Rhian M Touyz
Keyword(s):  
Cancer Treatment ◽  
Vascular Injury ◽  
Vascular Function ◽  
Vascular Dysfunction ◽  
Parp Inhibitor ◽  
Mesenteric Arteries ◽  
Cancer Drug ◽  
Vegf Inhibitors ◽  
Vegf Inhibitor ◽  
Trpm2 Channel

Hypertension is a common unwanted effect of VEGF inhibitors (VEGFi), which are used as anti-angiogenic drugs in cancer treatment. Clinical observations suggest that the combination of VEGFi with another anti-cancer drug, olaparib (PARP inhibitor [PARPi]), may attenuate the development of hypertension. However putative vascular mechanisms are unknown. PARP plays a major role in the activation of TRPM2, a redox-sensitive Ca 2+ channel, which is associated with hypertension-induced vascular dysfunction. We hypothesized that PARPi attenuates VEGFi-induced vascular injury through TRPM2/Ca 2+ -dependent pathways. Human vascular smooth muscle cells (hVSMC), human aortic endothelial cells (HAEC), and mouse mesenteric arteries were studied. Cells/arteries were exposed to axitinib (VEGFi) alone (3μM) or in combination with olaparib (1μM). Wire myography was used to assess vascular function. Axitinib reduced ACh-induced vasodilation (% relaxation: 70.5 [Ct] vs. 34.8 [Axi]), an effect blocked by olaparib. U46619- and ET-1-induced vasoconstriction were increased by axitinib (% KCl- U4 : 101.2 [Ct] vs. 141.4 [Axi]; ET-1 : 122.6 [Ct] vs. 152.5 [Axi]), an effect not observed with axitinib plus olaparib. TRPM2 channel blocker (8-Br-cADPR; 1μM) attenuated the hypercontractile effects and endothelial dysfunction induced by axitinib. Axitinib increased ROS production in hVSMC (RUL: 0.8±0.2 [Ct] vs. 1.1±0.09 [Axi]) and HAEC (0.7±0.4 [Ct] vs. 1.2±0.1 [Axi]), stimulated phosphorylation of the inhibitory site of eNOS (a.u.: 0.99±0.35 [Ct] vs. 1.35±0.10 [Axi]) and induced exaggerated Ca 2+ influx (AUC: 17541±4708 [Ct] vs. 22249±1438 [Axi]) in hVSMC. These effects were blocked by olaparib and 8-Br-cADPR. Axitinib also induced phosphorylation of MLC20 in hVSMC (a.u.: 0.028±0.02 [Ct] vs. 0.04±0.01 [Axi]) and aorta (a.u.: 0.3±0.01 [Ct] vs. 0.5±0.001 [Axi]). Our data indicate that PARP/TRPM2 inhibition attenuates axitinib-mediated vascular dysfunction and normalizes impaired hVSMC and HAEC signalling induced by VEGFi. We define a putative vasoprotective effect of olaparib that may ameliorate vascular injury and hypertension induced by VEGFi in cancer treatment.

Abstract 46: FOXP3+ T Regulatory Lymphocytes Counteract Angiotensin II-Induced Vascular Injury

Hypertension ◽  
2013 ◽  
Vol 62 (suppl_1) ◽  
Author(s):  
Muhammad Oneeb Rehman Mian ◽  
Tlili Barhoumi ◽  
Marie Briet ◽  
Adriana Cristina Ene ◽  
Asia Rehman ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Endothelial Dysfunction ◽  
T Lymphocytes ◽  
Vascular Injury ◽  
Mesenteric Arteries ◽  
Ros Production ◽  
Ang Ii ◽  
Induced Hypertension ◽  
Regulatory Lymphocytes

Introduction: T lymphocytes participate in the low-grade inflammatory response that causes vascular injury in angiotensin (Ang) II-induced hypertension. Ang II-induced hypertension and endothelial dysfunction are blunted in T and B lymphocyte-deficient ( Rag1 -/- ) mice, and restored with reconstitution of T cells. However, the role of T regulatory lymphocytes (Treg) in Ang II-induced vascular injury is unclear. We hypothesized that adoptive transfer of FOXP3-deficient (Scurfy) T lymphocytes vs. wild-type (WT) cells will exacerbate Ang II-induced vascular damage in Rag1 -/- mice. Methods: Eleven-week old male Rag1 -/- mice were injected IV with PBS/2% FBS (control), 10 7 WT or Scurfy T lymphocytes, and 2 weeks later underwent sham surgery or were infused with Ang II (490 ng/kg/min, s.c.) using mini-osmotic pumps for 14 days (n=3-8). Systolic (SBP) and diastolic (DBP) blood pressure were measured by telemetry. Vascular function and structure were assessed in second order mesenteric arteries by pressurized myography. Reactive oxygen species (ROS) production and fibronectin and collagen I and III expression were determined in aorta. Results: Ang II induced a 40 mmHg SBP rise in Rag1 -/- mice for all treatment groups, but DBP rise was ~10 mmHg greater for WT and Scurfy T cell-injected mice than for control mice ( P <0.01). Adoptive transfer of WT T cells restored Ang II induced-endothelial dysfunction in mesenteric arteries ( P <0.05), which was exaggerated in Scurfy T cell-injected mice ( P <0.01). Ang II induced a greater increase in ROS production in aortic perivascular fat of Scurfy T cell-injected mice compared to WT T cell-injected mice ( P <0.05). Ang II induced mesenteric artery stiffness ( P <0.01) and hypertrophic remodeling ( P <0.05) in control and Scurfy T cell-injected mice, but not in WT T cell-injected mice. Ang II increased fibronectin expression to a greater extent in the aorta of control and Scurfy T cell-injected mice compared to WT T cell-injected mice ( P <0.01). Collagen I and III content was greater in the aorta of control and Scurfy T cell-injected mice than in WT T cell-injected mice ( P <0.01), but expression was unaltered by Ang II treatment. Conclusion: Foxp3+ T regulatory lymphocytes have a protective role against Ang II-induced vascular remodeling.

scholarly journals Central administration of TRV027 improves baroreflex sensitivity and vascular reactivity in spontaneously hypertensive rats

2018 ◽  
Vol 132 (14) ◽  
pp. 1513-1527 ◽  
Author(s):  
Alynne Carvalho-Galvão ◽  
Blessing Ogunlade ◽  
Jiaxi Xu ◽  
Cristiane R.A. Silva-Alves ◽  
Leônidas G. Mendes-Júnior ◽  
...  
Keyword(s):  
Vascular Function ◽  
Baroreflex Sensitivity ◽  
Vascular Reactivity ◽  
Mesenteric Arteries ◽  
Control Group ◽  
Ang Ii ◽  
Central Administration ◽  
Spontaneously Hypertensive ◽  
Wistar Kyoto

TRV027 is a biased agonist for the Angiotensin (Ang)-II type 1 receptor (AT1R), able to recruit β-arrestin 2 independently of G-proteins activation. β-arrestin activation in the central nervous system (CNS) was suggested to oppose the effects of Ang-II. The present study evaluates the effect of central infusion of TRV027 on arterial pressure (AP), autonomic function, baroreflex sensitivity (BRS), and peripheral vascular reactivity. Spontaneously hypertensive (SH) and Wistar Kyoto (WKY) rats were treated with TRV027 for 14 days (20 ng/h) delivered to the lateral ventricle via osmotic minipumps. Mechanistic studies were performed in HEK293T cells co-transfected with AT1R and Ang converting enzyme type 2 (ACE2) treated with TRV027 (100 nM) or Ang-II (100 nM). TRV027 infusion in SH rats (SHR) reduced AP (~20 mmHg, P<0.05), sympathetic vasomotor activity (ΔMAP = −47.2 ± 2.8 compared with −64 ± 5.1 mmHg, P<0.05) and low-frequency (LF) oscillations of AP (1.7 ± 0.2 compared with 5.8 ± 0.4 mmHg, P<0.05) compared with the SHR control group. TRV027 also increased vagal tone, improved BRS, reduced the reactivity of mesenteric arteries to Ang-II and increased vascular sensitivity to phenylephrine (Phe), acetylcholine, (ACh), and sodium nitroprusside (SNP). In vitro, TRV027 prevented the Ang-II-induced up-regulation of ADAM17 and in contrast with Ang-II, had no effects on ACE2 activity and expression levels. Furthermore, TRV027 induced lesser interactions between AT1R and ACE2 compared with Ang-II. Together, these data suggest that due to its biased activity for the β-arrestin pathway, TRV027 has beneficial effects within the CNS on hypertension, autonomic and vascular function, possibly through preserving ACE2 compensatory activity in neurones.

Changes in NOS activity and protein expression during acute and prolonged ANG II administration

2002 ◽  
Vol 282 (1) ◽  
pp. R31-R37 ◽  
Author(s):  
Carol Moreno ◽  
Almudena López ◽  
María T. Llinás ◽  
Francisca Rodríguez ◽  
Antonio López-Farré ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Protein Expression ◽  
Time Course ◽  
Renal Cortex ◽  
Renal Medulla ◽  
Mesenteric Arteries ◽  
Ang Ii ◽  
Protein Levels ◽  
Renal Changes ◽  
Phenylephrine Infusion

The aim of this study was to assess the effects of acute or prolonged increases of ANG II on nitric oxide synthase (NOS) activities and protein expression in mesenteric resistance vessels, left ventricle, renal cortex, and renal medulla. The response of NOS activities to ANG II is compared with that induced by phenylephrine. ANG II or phenylephrine were infused over either 3 h or 3 days to conscious rats. NOS activity was examined by measuring the rate of conversion ofl-[14C]arginine tol-[14C]citrulline. Protein levels of endothelial (e) and neuronal (n) NOS were determined by Western blot analysis. Arterial pressure (AP) increased ( P < 0.05) during acute and prolonged ANG II infusion. Ca2+-dependent NOS activity values (pmol of citrulline · min−1 · g wet wt−1) for control rats were 21 ± 9 in mesenteric arteries, 13 ± 7 in left ventricle, 14 ± 8 in renal cortex, and 411 ± 70 in renal medulla. Acute ANG II infusion increased ( P < 0.05) Ca2+-dependent NOS activity in renal cortex and renal medulla (81 ± 18 and 611 ± 48, respectively), but no differences were found in mesenteric arteries and left ventricle with respect to control rats. In contrast to the renal changes in NOS activity, acute ANG II infusion did not modify eNOS or nNOS expression in any of the tissues examined. Prolonged ANG II infusion increased ( P < 0.05) Ca2+-dependent NOS activity in mesenteric arteries (70 ± 17), renal cortex (104 ± 31), and left ventricle (49 ± 8) and did not elicit changes in renal medulla. After a prolonged ANG II infusion, eNOS and nNOS levels increased in all tissues examined with the exception of eNOS in the mesenteric arteries and nNOS in the left ventricle, which were not altered. Acute and prolonged phenylephrine infusion elevated AP to a similar extent as ANG II but only elicited significant increments of Ca2+-dependent NOS activity in renal cortex. These data indicate that acute and prolonged elevations in ANG II upregulate Ca2+-dependent NOS activity and protein expression in different tissues related to the control of blood pressure. However, these ANG II effects are heterogeneous with respect to the tissue implicated, the time course of the stimulation, and the NOS isoform involved. Phenylephrine only induces a significant elevation of Ca2+-dependent NOS activity in renal cortex.

Reduced expression of SKCa and IKCa channel proteins in rat small mesenteric arteries during angiotensin II-induced hypertension

2007 ◽  
Vol 292 (5) ◽  
pp. H2275-H2284 ◽  
Author(s):  
Rob H. P. Hilgers ◽  
R. Clinton Webb
Keyword(s):  
Angiotensin Ii ◽  
Channel Blocker ◽  
Mesenteric Arteries ◽  
Ang Ii ◽  
Expression Levels ◽  
Protein Levels ◽  
Channel Proteins ◽  
Induced Hypertension ◽  
Relaxation Responses

Ca2+-activated K+ channels (KCa), in particular, the small and intermediate KCa (SKCa and IKCa, respectively) channels, are key players in endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation in small arteries. Hypertension is characterized by an endothelial dysfunction, possibly via reduced EDHF release and/or function. We hypothesize that during angiotensin II (14 days)-induced hypertension (ANG II-14d), the contribution of SKCa and IKCa channels in ACh-induced relaxations is reduced due to decreased expression of SKCa and IKCa channel proteins in rat small mesenteric arteries (MAs). Nitric oxide- and prostacyclin-independent vasorelaxation to ACh was similar in small MAs of sham-operated and ANG II-14d rats. Catalase had no inhibitory effects on these relaxations. The highly selective SKCa channel blocker UCL-1684 almost completely blocked these responses in MAs of sham-operated rats but partially in MAs of ANG II-14d rats. These changes were pressure dependent since UCL-1684 caused a greater inhibition in MAs of 1-day ANG II-treated normotensive rats compared with ANG II-14d rats. Expression levels of both mRNA and protein SK3 were significantly reduced in MAs of ANG II-14d rats. The IKCa channel blocker 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34) resulted in comparable reductions in the relaxation responses to ACh in MAs of sham-operated and ANG II-14d rats. Relative mRNA expression levels of IK1 were significantly reduced in MAs of ANG II-14d rats, whereas protein levels of IK1 were not but tended to be lower in MAs of ANG II-14d rats. The findings demonstrate that EDHF-like responses are not compromised in a situation of reduced functional activity and expression of SK3 channels in small MAs of ANG II-induced hypertensive rats. The role of IK1 channels is less clear but might compensate for reduced SK3 activity.

Abstract 099: Fetuin-A and Toll-like Receptor 4 Regulate Vascular Function: Role of Nox1

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Augusto C Montezano ◽  
Karla B Neves ◽  
Rheure A Lopes ◽  
Susan Leckerman ◽  
Anastasiya Strembitska ◽  
...  
Keyword(s):  
Endothelial Dysfunction ◽  
Protein Oxidation ◽  
Vascular Function ◽  
Vascular Dysfunction ◽  
Rho Kinase ◽  
Mesenteric Arteries ◽  
Ros Production ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Fetuin A

Fetuin-A (FetA) regulates calcium and phosphate homeostasis. It is also an agonist to toll-like receptor 4 (TLR4) and is related to insulin resistance and inflammation. FetA has also been associated with endothelial dysfunction, which is regulated by oxidative stress. Mechanisms whereby FetA influences vascular function are unknown. We hypothesized that FetA through TLR4 and ROS production induces vascular dysfunction. Mesenteric arteries and vascular cells from WKY rats were studied. Vascular function was analysed by wire myography in the presence or absence of FetA (50 ng/mL) and/or CLI095 (CLI - 10-6M - TLR4 inhibitor). Levels of reactive oxygen species (ROS) were measured by chemiluminescence, Amplex Red (H2O2) and ELISA (nitrotyrosine) Protein oxidation and levels were measured by immunoblotting. WKY vessels exposed to FetA were less sensitive to acetylcholine (Ach)-induced and sodium nitroprusside (SNP)-induced relaxation, while sensitivity to phenylephrine was increased by FetA; an effect blocked by N-acetylcysteine (antioxidant) and ML171 (Nox1 inhibitor). Inhibition of TLR4 blocked FetA effects on endothelial-dependent relaxation and contraction, but not on endothelial-independent relaxation. FetA increased ROS production (131±49.2%), but decreased H2O2 intracellular levels (63±14%) in endothelial cells (EC) (vs. veh, p<0.05); an effect blocked by CLI095. ROS production (66±12.2%), as well as, H2O2 (45±8%) and ONOO- (105±31.6%) levels, were increased by FetA in VSMCs (vs. veh, p<0.05). Protein oxidation was increased by FetA in VSMCs (103±26% vs. veh, p<0.05). In EC, eNOS inactivation (136±38%) and JNK activation (84±5%) were increased by FetA (vs. veh, p<0.05). In VSMCs, Rho kinase activity was increased (200±25% vs. veh, p<0.05) at 30 min; while myosin light chain (MLC) activation was only increased (25±3.56% vs. veh, p<0.05) at 15 min. In summary, FetA influences vascular function through Nox1-ROS dependent mechanisms. FetA-induced endothelial dysfunction and contractile responses involve TLR4. Our findings identify a novel system whereby FetA differentially influences vascular function through Nox1-ROS and TLR4. Vascular responses to FetA may depend on the specific pathway activated.

Increase of PTP levels in vascular injury and in cultured aortic smooth muscle cells treated with specific growth factors

2004 ◽  
Vol 287 (5) ◽  
pp. H2201-H2208 ◽  
Author(s):  
Yingzi Chang ◽  
Daming Zhuang ◽  
Chunxiang Zhang ◽  
Aviv Hassid
Keyword(s):  
Smooth Muscle ◽  
Growth Factors ◽  
Smooth Muscle Cells ◽  
Vascular Injury ◽  
Muscle Cells ◽  
Ang Ii ◽  
Aortic Smooth Muscle Cells ◽  
Aortic Smooth Muscle ◽  
Protein Levels ◽  
Ptp 1B

Migration and proliferation of vascular smooth muscle cells are key events in injury-induced neointima formation. Several growth factors and ANG II are thought to be involved in neointima formation. A recent report indicated that vascular injury is associated with increased mRNA levels of protein tyrosine phosphatase (PTP)-1B (PTP-1B). In the present study, we tested the following hypotheses: 1) rat carotid artery injury induces the expression of PTP-1B, Src homology-2 domain phosphatase (SHP-2), and PTP-proline, glutamate, serine, and threonine sequence (PEST) protein; and 2) polypeptide growth factors as well as ANG II increase the levels of tyrosine phosphatases in cultured rat aortic smooth muscle cells. We found that vascular injury induced by balloon catheter increases the protein levels of aforementioned phosphatases and that these effects occur in a PTP specific, as well as temporally and regionally specific, manner. Moreover, treatment of cultured primary rat aortic smooth muscle cells with PDGF or bFGF, but not with IGF1, EGF, or ANG II, increases PTP-1B, SHP-2, and PTP-PEST protein levels. These results suggest that increased PDGF and bFGF levels, occurring after vascular injury, may induce expression of several PTPs.

Abstract P220: Matrix Metalloproteinase 2 Knockout Protects from Angiotensin II-induced Vascular Injury

Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Julio C Fraulob-Aquino ◽  
Tlili Barhoumi ◽  
Muhammad O Mian ◽  
Noureddine Idris-Khodja ◽  
Ku-Geng Huo ◽  
...  
Keyword(s):  
T Cells ◽  
Vascular Injury ◽  
Mesenteric Arteries ◽  
Matrix Metalloproteinase 2 ◽  
Ang Ii ◽  
Wild Type ◽  
Vascular Cell ◽  
Induced Hypertension ◽  
Relationship Of ◽  
Transplantation Experiments

Objective: Matrix metalloproteinase-2 (MMP2) participates in the mechanisms of vascular injury in atherosclerosis. Whether MMP2 plays a role in angiotensin (Ang) II-induced hypertension and vascular remodeling is unknown. We hypothesized that Mmp2 knockout ( Mmp2 -/- ) would prevent Ang II-induced hypertension and vascular injury. Methods and Results: Fourteen days of Ang II infusion (1000 ng/kg/min, SC) increased systolic blood pressure (SBP, 161±9 vs 122±3 mm Hg, P <0.05) and decreased vasodilatory responses to acetylcholine (33±5 vs 83±3%, P <0.001), increased the media/lumen (4.8±0.4 vs 3.1±0.1%, P <0.001) and media cross-sectional area (7223±467 vs 5346±336 μm 2 , P <0.05) and enhanced stiffness ( P <0.05), as shown by a leftward shift of the stress/strain relationship of mesenteric arteries in wild-type mice. Ang II enhanced aortic (73±6 vs 6±1 relative fluorescence units [RFU]/μm 2 , P <0.001) and perivascular adipose tissue (PVAT) reactive oxygen species generation (76±11 vs 12±1 RFU/μm 2 , P <0.001), aortic VCAM-1 (17±3 vs 5±1 RFU/μm 2 , P <0.001) and MCP-1 expression (71±14 vs 11±3 RFU/μm 2 , P <0.001), PVAT monocyte/macrophage (1.8±0.3 vs 0.1±0.1 % of PVAT, P <0.001) and T cell infiltration (56±14 vs 16±9 cells/μm 2 , P <0.05) and the fraction of spleen activated CD4 + CD69 + (17±2 vs 10±1 % of CD4+ T cells, P <0.001), CD8 + CD69 + T cells (11±1 vs 5±1 % of CD4+ T cells, P <0.001) and Ly-6C hi monocytes (53±6 vs 25±2 % event, P <0.001). Ang II increased phosphorylation of epidermal growth factor receptor 1.9±0.2-fold and extracellular-signal-regulated kinase 1/2 1.4±0.1-fold in vascular smooth muscle cells isolated from mesenteric arteries of wild-type mice ( P <0.05). Mmp2 knockout prevented or reduced all of the above ( P <0.05) except SBP elevation. Bone marrow transplantation experiments revealed that Ang II-induced hypertension was impaired in absence of immune cell MMP2 and endothelial dysfunction was blunted or reduced in absence of immune or vascular cell MMP2 ( P <0.05). Conclusions: Mmp2 knockout prevented Ang II-induced vascular injury but not hypertension. Bone marrow transplantation experiments revealed a complex relationship of immune and vascular cell MMP2 in the development of Ang II-induced hypertension and endothelial dysfunction.

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