41 results on '"Moral‐Sanz, Javier"'
Search Results
2. Modulation of the LKB1-AMPK Signalling Pathway Underpins Hypoxic Pulmonary Vasoconstriction and Pulmonary Hypertension
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Evans, A. Mark, Lewis, Sophronia A., Ogunbayo, Oluseye A., Moral-Sanz, Javier, Peers, Chris, editor, Kumar, Prem, editor, Wyatt, Christopher, editor, Gauda, Estelle, editor, Nurse, Colin A., editor, and Prabhakar, Nanduri, editor
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- 2015
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3. The structural conformation of the tachykinin domain drives the anti‐tumoural activity of an octopus peptide in melanoma BRAF V600E
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Moral‐Sanz, Javier, primary, Fernandez‐Rojo, Manuel A., additional, Colmenarejo, Gonzalo, additional, Kurdyukov, Sergey, additional, Brust, Andreas, additional, Ragnarsson, Lotten, additional, Andersson, Åsa, additional, Vila, Sabela F., additional, Cabezas‐Sainz, Pablo, additional, Wilhelm, Patrick, additional, Vela‐Sebastián, Ana, additional, Fernández‐Carrasco, Isabel, additional, Chin, Yanni K. Y., additional, López‐Mancheño, Yaiza, additional, Smallwood, Taylor B., additional, Clark, Richard J., additional, Fry, Bryan G., additional, King, Glenn F., additional, Ramm, Grant A., additional, Alewood, Paul F., additional, Lewis, Richard J., additional, Mulvenna, Jason P., additional, Boyle, Glen M., additional, Sanchez, Laura E., additional, Neely, G. Gregory, additional, Miles, John J., additional, and Ikonomopoulou, Maria P., additional
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- 2022
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4. AMPK deficiency in smooth muscles causes persistent pulmonary hypertension after birth and premature death
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Moral-Sanz, Javier, primary, Lewis, Sophronia A, additional, MacMillan, Sandy, additional, Meloni, Marco, additional, McClafferty, Heather, additional, Viollet, Benoit, additional, Foretz, Marc, additional, del-Pozo, Jorge, additional, and Evans, A. Mark, additional
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- 2022
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5. The structural conformation of the tachykinin domain drives the anti-tumoural activity of an octopus peptide in melanoma BRAFV600E.
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Moral‐Sanz, Javier, Fernandez‐Rojo, Manuel A., Colmenarejo, Gonzalo, Kurdyukov, Sergey, Brust, Andreas, Ragnarsson, Lotten, Andersson, Åsa, Vila, Sabela F., Cabezas‐Sainz, Pablo, Wilhelm, Patrick, Vela‐Sebastián, Ana, Fernández‐Carrasco, Isabel, Chin, Yanni K. Y., López‐Mancheño, Yaiza, Smallwood, Taylor B., Clark, Richard J., Fry, Bryan G., King, Glenn F., Ramm, Grant A., and Alewood, Paul F.
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ADENOSINE triphosphate , *GENETIC mutation , *MELANOMA , *MOLECULAR models , *RNA , *FISHES , *TRANSFERASES , *RESEARCH funding , *MOLLUSKS , *CELL lines , *CALCIUM , *REACTIVE oxygen species , *ANIMALS , *MICE - Abstract
Background and Purpose: Over past decades, targeted therapies and immunotherapy have improved survival and reduced the morbidity of patients with BRAF-mutated melanoma. However, drug resistance and relapse hinder overall success. Therefore, there is an urgent need for novel compounds with therapeutic efficacy against BRAF-melanoma. This prompted us to investigate the antiproliferative profile of a tachykinin-peptide from the Octopus kaurna, Octpep-1 in melanoma.Experimental Approach: We evaluated the cytotoxicity of Octpep-1 by MTT assay. Mechanistic insights on viability and cellular damage caused by Octpep-1 were gained via flow cytometry and bioenergetics. Structural and pharmacological characterization was conducted by molecular modelling, molecular biology, CRISPR/Cas9 technology, high-throughput mRNA and calcium flux analysis. In vivo efficacy was validated in two independent xerograph animal models (mice and zebrafish).Key Results: Octpep-1 selectively reduced the proliferative capacity of human melanoma BRAFV600E -mutated cells with minimal effects on fibroblasts. In melanoma-treated cells, Octpep-1 increased ROS with unaltered mitochondrial membrane potential and promoted non-mitochondrial and mitochondrial respiration with inefficient ATP coupling. Molecular modelling revealed that the cytotoxicity of Octpep-1 depends upon the α-helix and polyproline conformation in the C-terminal region of the peptide. A truncated form of the C-terminal end of Octpep-1 displayed enhanced potency and efficacy against melanoma. Octpep-1 reduced the progression of tumours in xenograft melanoma mice and zebrafish.Conclusion and Implications: We unravel the intrinsic anti-tumoural properties of a tachykinin peptide. This peptide mediates the selective cytotoxicity in BRAF-mutated melanoma in vitro and prevents tumour progression in vivo, providing a foundation for a therapy against melanoma. [ABSTRACT FROM AUTHOR]- Published
- 2022
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6. The structural conformation of the tachykinin domain drives the anti-tumoural activity of an octopus peptide in melanoma BRAFV600E.
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Moral‐Sanz, Javier, Fernandez‐Rojo, Manuel A., Colmenarejo, Gonzalo, Kurdyukov, Sergey, Brust, Andreas, Ragnarsson, Lotten, Andersson, Åsa, Vila, Sabela F., Cabezas‐Sainz, Pablo, Wilhelm, Patrick, Vela‐Sebastián, Ana, Fernández‐Carrasco, Isabel, Chin, Yanni K. Y., López‐Mancheño, Yaiza, Smallwood, Taylor B., Clark, Richard J., Fry, Bryan G., King, Glenn F., Ramm, Grant A., and Alewood, Paul F.
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ADENOSINE triphosphate ,GENETIC mutation ,MELANOMA ,MOLECULAR models ,RNA ,FISHES ,TRANSFERASES ,RESEARCH funding ,MOLLUSKS ,CELL lines ,CALCIUM ,REACTIVE oxygen species ,ANIMALS ,MICE - Abstract
Background and Purpose: Over past decades, targeted therapies and immunotherapy have improved survival and reduced the morbidity of patients with BRAF-mutated melanoma. However, drug resistance and relapse hinder overall success. Therefore, there is an urgent need for novel compounds with therapeutic efficacy against BRAF-melanoma. This prompted us to investigate the antiproliferative profile of a tachykinin-peptide from the Octopus kaurna, Octpep-1 in melanoma.Experimental Approach: We evaluated the cytotoxicity of Octpep-1 by MTT assay. Mechanistic insights on viability and cellular damage caused by Octpep-1 were gained via flow cytometry and bioenergetics. Structural and pharmacological characterization was conducted by molecular modelling, molecular biology, CRISPR/Cas9 technology, high-throughput mRNA and calcium flux analysis. In vivo efficacy was validated in two independent xerograph animal models (mice and zebrafish).Key Results: Octpep-1 selectively reduced the proliferative capacity of human melanoma BRAFV600E -mutated cells with minimal effects on fibroblasts. In melanoma-treated cells, Octpep-1 increased ROS with unaltered mitochondrial membrane potential and promoted non-mitochondrial and mitochondrial respiration with inefficient ATP coupling. Molecular modelling revealed that the cytotoxicity of Octpep-1 depends upon the α-helix and polyproline conformation in the C-terminal region of the peptide. A truncated form of the C-terminal end of Octpep-1 displayed enhanced potency and efficacy against melanoma. Octpep-1 reduced the progression of tumours in xenograft melanoma mice and zebrafish.Conclusion and Implications: We unravel the intrinsic anti-tumoural properties of a tachykinin peptide. This peptide mediates the selective cytotoxicity in BRAF-mutated melanoma in vitro and prevents tumour progression in vivo, providing a foundation for a therapy against melanoma. [ABSTRACT FROM AUTHOR]- Published
- 2022
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7. Hypoxic pulmonary vasoconstriction, carotid body function and erythropoietin production in adult rats perinatally exposed to hyperoxia
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Prieto-Lloret, Jesus, Ramirez, Maria, Olea, Elena, Moral-Sanz, Javier, Cogolludo, Angel, Castañeda, Javier, Yubero, Sara, Agapito, Teresa, Gomez-Niño, Angela, Rocher, Asuncion, Rigual, Ricardo, Obeso, Ana, Perez-Vizcaino, Francisco, and González, Constancio
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- 2015
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8. Maturation of [O.sub.2] sensing and signaling in the chicken ductus arteriosus
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Cogolludo, Angel L., Moral-Sanz, Javier, van der Sterren, Saskia, Frazziano, Giovanna, van Cleef, Anne N.H., Menendez, Carmen, Zoer, Bea, Moreno, Enrique, Roman, Angela, Perez-Vizeaino, Francisco, and Villamor, Eduardo
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Ductus arteriosus -- Research ,Ductus arteriosus -- Models ,Potassium channels -- Physiological aspects ,Potassium channels -- Research ,Mitochondria -- Physiological aspects ,Mitochondria -- Research ,Chickens -- Physiological aspects ,Chickens -- Research ,Oxygen -- Physiological transport ,Oxygen -- Models ,Oxygen -- Research ,Biological sciences - Abstract
The increase in [O.sub.2] tension after birth is a major factor stimulating ductus arteriosus (DA) constriction and closure. Here we studied the role of the mitochondrial electron transport chain (ETC) as sensor, [H.sub.2][O.sub.2] as mediator, and voltage-gated potassium ([K.sub.v]) channels and Rho kinase as effectors of [O.sub.2]-induced contraction in the chicken DA during fetal development. Switching from 0% to 21% [O.sub.2] contracted the pulmonary side of the mature DA (mature pDA) but had no effect in immature pDA and relaxed the aortic side of the mature DA (mature aDA). This contraction of the pDA was attenuated by inhibitors of the mitochondrial ETC and by the [H.sub.2][O.sub.2] scavenger polyethylene glycol (PEG)-catalase. Moreover, [O.sub.2] increased reactive oxygen species (ROS) production, measured with the fluorescent probes dihydroethidium and 2',7'-dichlorofluorescein, only in mature pDA. The [H.sub.2][O.sub.2] analog t-butyl-hydroperoxide mimicked the responses to 02 in the three vessels. In contrast to immature pDA cells, mature pDA cells exhibited high-amplitude [O.sub.2]-sensitive potassium currents. The Kv channel blocker 4-aminopyridine prevented the current inhibition elicited by [O.sub.2]. The L-type [Ca.sup.2+] ([Ca.sub.L]) channel blocker nifedipine and the Rho kinase inhibitors Y-27632 and hydroxyfasudil induced a similar relaxation when mature pDA were stimulated with [O.sub.2] or [H.sub.2][O.sub.2]. Moreover, the sensitivity to these drugs increased with maturation. Our results indicate the presence of a common mechanism for [O.sub.2] sensing/signaling in mammalian and nonmammalian DA and favor the idea that, rather than a single mechanism, a parallel maturation of the sensor and effectors is critical for [O.sub.2] sensitivity appearance during development. oxygen sensing; potassium channels; hydrogen peroxide doi:10.1152/ajplung.00092.2009.
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- 2009
9. ERK and mTORC1 Inhibitors Enhance the Anti-Cancer Capacity of the Octpep-1 Venom-Derived Peptide in Melanoma BRAF(V600E) Mutations
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Moral-Sanz, Javier, primary, Fernandez-Rojo, Manuel A., additional, Potriquet, Jeremy, additional, Mukhopadhyay, Pamela, additional, Brust, Andreas, additional, Wilhelm, Patrick, additional, Smallwood, Taylor B., additional, Clark, Richard J., additional, Fry, Bryan G., additional, Alewood, Paul F., additional, Waddell, Nicola, additional, Miles, John J., additional, Mulvenna, Jason P., additional, and Ikonomopoulou, Maria P., additional
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- 2021
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10. Diabetes induces pulmonary artery endothelial dysfunction by NADPH oxidase induction
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Lopez-Lopez, Jose G., Moral-Sanz, Javier, Frazziano, Giovanna, Gomez-Villalobos, Maria J., Flores-Hernandez, Jorge, Monjaraz, Eduardo, Cogolludo, Angel, and Perez-Vizcaino, Francisco
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Endothelium -- Health aspects ,Diabetes -- Risk factors ,NADP (Coenzyme) -- Health aspects ,Biological sciences - Abstract
Recent data suggest that diabetes is a risk factor for pulmonary hypertension. The aim of the present study was to analyze whether diabetes induces endothelial dysfunction in pulmonary arteries and the mechanisms involved. Male Sprague-Dawley rats were randomly divided into a control (saline) and a diabetic group (70 mg/[kg.sup.-1] streptozotocin). After 6 wk, intrapulmonary arteries were mounted for isometric tension recording, and endothelial function was tested by the relaxant response to acetylcholine. Protein expression and localization were measured by Western blot and immunohistochemistry and superoxide production by dihydroethidium staining. Pulmonary arteries from diabetic rats showed impaired relaxant response to acetylcholine and reduced vasoconstrictor response to the nitric oxide (NO) synthase inhibitor [sub.L]-NAME, whereas the response to nitroprusside and the expression of endothelial NO synthase remained unchanged. Endothelial dysfunction was reversed by addition of superoxide dismutase or the NADPH oxidase inhibitor apocynin. An increase in superoxide production and increased expression of the NADPH oxidase regulatory subunit [p47.sup.phox] were also found in pulmonary arteries from diabetic rats. In conclusion, the pulmonary circulation is a target for diabetes-induced endothelial dysfunction via enhanced NADPH oxidase-derived superoxide production. pulmonary arteries; superoxide; nitric oxide; streptozotocin
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- 2008
11. Different patterns of pulmonary vascular disease induced by type 1 diabetes and moderate hypoxia in rats
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Moral-Sanz, Javier, Lopez-Lopez, Jose G., Menendez, Carmen, Moreno, Enrique, Barreira, Bianca, Morales-Cano, Daniel, Escolano, Lucia, Fernandez-Segoviano, Pilar, Villamor, Eduardo, Cogolludo, Angel, Perez-Vizcaino, Francisco, and Moreno, Laura
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- 2012
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12. Activation of neutral sphingomyelinase is involved in acute hypoxic pulmonary vasoconstriction
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Cogolludo, Angel, Moreno, Laura, Frazziano, Giovanna, Moral-Sanz, Javier, Menendez, Carmen, Castañeda, Javier, González, Constancio, Villamor, Eduardo, and Perez-Vizcaino, Francisco
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- 2009
13. Activation of K v 7 channels as a novel mechanism for NO/cGMP‐induced pulmonary vasodilation
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Mondéjar‐Parreño, Gema, primary, Moral‐Sanz, Javier, additional, Barreira, Bianca, additional, De la Cruz, Alicia, additional, Gonzalez, Teresa, additional, Callejo, Maria, additional, Esquivel‐Ruiz, Sergio, additional, Morales‐Cano, Daniel, additional, Moreno, Laura, additional, Valenzuela, Carmen, additional, Perez‐Vizcaino, Francisco, additional, and Cogolludo, Angel, additional
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- 2019
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14. Pulmonary arterial dysfunction in insulin resistant obese Zucker rats
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Cogolludo Angel, Moreno Enrique, Moreno Laura, Menendez Carmen, Moral-Sanz Javier, and Perez-Vizcaino Francisco
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Diseases of the respiratory system ,RC705-779 - Abstract
Abstract Background Insulin resistance and obesity are strongly associated with systemic cardiovascular diseases. Recent reports have also suggested a link between insulin resistance with pulmonary arterial hypertension. The aim of this study was to analyze pulmonary vascular function in the insulin resistant obese Zucker rat. Methods Large and small pulmonary arteries from obese Zucker rat and their lean counterparts were mounted for isometric tension recording. mRNA and protein expression was measured by RT-PCR or Western blot, respectively. KV currents were recorded in isolated pulmonary artery smooth muscle cells using the patch clamp technique. Results Right ventricular wall thickness was similar in obese and lean Zucker rats. Lung BMPR2, KV1.5 and 5-HT2A receptor mRNA and protein expression and KV current density were also similar in the two rat strains. In conductance and resistance pulmonary arteries, the similar relaxant responses to acetylcholine and nitroprusside and unchanged lung eNOS expression revealed a preserved endothelial function. However, in resistance (but not in conductance) pulmonary arteries from obese rats a reduced response to several vasoconstrictor agents (hypoxia, phenylephrine and 5-HT) was observed. The hyporesponsiveness to vasoconstrictors was reversed by L-NAME and prevented by the iNOS inhibitor 1400W. Conclusions In contrast to rat models of type 1 diabetes or other mice models of insulin resistance, the obese Zucker rats did not show any of the characteristic features of pulmonary hypertension but rather a reduced vasoconstrictor response which could be prevented by inhibition of iNOS.
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- 2011
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15. Activation of Kv 7 channels as a novel mechanism for NO/cGMP-induced pulmonary vasodilation.
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Mondéjar‐Parreño, Gema, Moral‐Sanz, Javier, Barreira, Bianca, De la Cruz, Alicia, Gonzalez, Teresa, Callejo, Maria, Esquivel‐Ruiz, Sergio, Morales‐Cano, Daniel, Moreno, Laura, Valenzuela, Carmen, Perez‐Vizcaino, Francisco, Cogolludo, Angel, Mondéjar-Parreño, Gema, Moral-Sanz, Javier, Esquivel-Ruiz, Sergio, Morales-Cano, Daniel, and Perez-Vizcaino, Francisco
- Abstract
Background and Purpose: The NO/cGMP pathway represents a major physiological signalling controlling tone in pulmonary arteries (PA), and drugs activating this pathway are used to treat pulmonary arterial hypertension. Kv channels expressed in PA smooth muscle cells (PASMCs) are key determinants of vascular tone. We aimed to analyse the contribution of Kv 1.5 and Kv 7 channels in the electrophysiological and vasodilating effects evoked by NO donors and the GC stimulator riociguat in PA.Experimental Approach: Kv currents were recorded in isolated rat PASMCs using the patch-clamp technique. Vascular reactivity was assessed in a wire myograph.Key Results: The NO donors diethylamine NONOate diethylammonium (DEA-NO) and sodium nitroprusside hyperpolarized the membrane potential and induced a bimodal effect on Kv currents (augmenting the current between -40 and -10 mV and decreasing it at more depolarized potentials). The hyperpolarization and the enhancement of the current were suppressed by Kv 7 channel inhibitors and by the GC inhibitor ODQ but preserved when Kv 1.5 channels were inhibited. Additionally, DEA-NO enhanced Kv 7.5 currents in COS7 cells expressing the KCNQ5 gene. Riociguat increased Kv currents at all potentials ≥-40 mV and induced membrane hyperpolarization. Both effects were prevented by Kv 7 inhibition. Likewise, PA relaxation induced by NO donors and riociguat was attenuated by Kv 7 inhibitors.Conclusions and Implications: NO donors and riociguat enhance Kv 7 currents, leading to PASMC hyperpolarization. This mechanism contributes to NO/cGMP-induced PA vasodilation. Our study identifies Kv 7 channels as a novel mechanism of action of vasodilator drugs used in the treatment of pulmonary arterial hypertension. [ABSTRACT FROM AUTHOR]- Published
- 2019
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16. The LKB1–AMPK-α1 signaling pathway triggers hypoxic pulmonary vasoconstriction downstream of mitochondria
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Moral-Sanz, Javier, primary, Lewis, Sophronia A., additional, MacMillan, Sandy, additional, Ross, Fiona A., additional, Thomson, Adrian, additional, Viollet, Benoit, additional, Foretz, Marc, additional, Moran, Carmel, additional, Hardie, D. Grahame, additional, and Evans, A. Mark, additional
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- 2018
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17. The emerging role of AMPK in the regulation of breathing and oxygen supply
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Evans, A Mark, Mahmoud, Amira D, Moral-Sanz, Javier, and Hartmann, Sandy
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Regulation of breathing is critical to our capacity to accommodate deficits in oxygen availability and demand during, for example, sleep and ascent to altitude. It is generally accepted that a fall in arterial oxygen increases afferent discharge from the carotid bodies to the brainstem and thus delivers increased ventilatory drive, which restores oxygen supply and protects against hypoventilation and apnoea. However, the precise molecular mechanisms involved remain unclear. We recently identified as critical to this process the AMP-activated protein kinase (AMPK), which is key to the cell-autonomous regulation of metabolic homoeostasis. This observation is significant for many reasons, not least because recent studies suggest that the gene for the AMPK-α1 catalytic subunit has been subjected to natural selection in high-altitude populations. It would appear, therefore, that evolutionary pressures have led to AMPK being utilized to regulate oxygen delivery and thus energy supply to the body in the short, medium and longer term. Contrary to current consensus, however, our findings suggest that AMPK regulates ventilation at the level of the caudal brainstem, even when afferent input responses from the carotid body are normal. We therefore hypothesize that AMPK integrates local hypoxic stress at defined loci within the brainstem respiratory network with an index of peripheral hypoxic status, namely afferent chemosensory inputs. Allied to this, AMPK is critical to the control of hypoxic pulmonary vasoconstriction and thus ventilation-perfusion matching at the lungs and may also determine oxygen supply to the foetus by, for example, modulating utero-placental blood flow.
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- 2016
18. AMP-activated protein kinase inhibits Kv1.5 channel currents of pulmonary arterial myocytes in response to hypoxia and inhibition of mitochondrial oxidative phosphorylation
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Moral-Sanz, Javier, Mahmoud, Amira, Ross, Fiona A., Eldstrom, Jodene, Fedida, David, Hardie, D. Grahame, and Evans, A. Mark
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Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage-gated potassium channels (Kv) in pulmonary arterial smooth muscle cells (Archer et al. 2004; Michelakis et al. 2004) that is mediated by the inhibition of mitochondrial oxidative phosphorylation (Firth et al. 2009). We sought to determine the role in this process of the AMP-activated protein kinase (AMPK), which is intimately coupled to mitochondrial function due to its activation by LKB1-dependent phosphorylation in response to increases in the cellular AMP:ATP and/or ADP:ATP ratios. Inhibition of complex I of the mitochondrial electron transport chain using phenformin activated AMPK and inhibited Kv currents in pulmonary arterial myocytes, consistent with previously reported effects of mitochondrial inhibitors (Firth et al. 2008). Myocyte Kv currents were also markedly inhibited upon AMPK activation by A769662, AICAR and C13 and by intracellular dialysis from a patch-pipette of activated (thiophosphorylated) recombinant AMPK heterotrimers (α2β2γ1 or α1β1γ1). Hypoxia and inhibitors of mitochondrial oxidative phosphorylation reduced AMPK-sensitive K+ currents, which were also blocked by the selective Kv1.5 blocker DPO-1 but unaffected by the presence of the BKCa channel blocker paxilline. Moreover, recombinant human Kv1.5 channels were phosphorylated by AMPK in cell-free assays, and K+ currents carried by Kv1.5 stably expressed in HEK 293 cells were inhibited by intracellular dialysis of AMPK heterotrimers and by A769662, the effects of which were blocked by compound C. We conclude that AMPK mediates Kv channel inhibition by hypoxia in pulmonary arterial myocytes, at least in part, through phosphorylation of Kv1.5 and/or an associated protein.
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- 2016
19. Hypoxia-induced contraction of chicken embryo mesenteric arteries: mechanisms and developmental changes
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Brinks, Leonie, primary, Moonen, Rob M. J., additional, Moral-Sanz, Javier, additional, Barreira, Bianca, additional, Kessels, Lilian, additional, Perez-Vizcaino, Francisco, additional, Cogolludo, Angel, additional, and Villamor, Eduardo, additional
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- 2016
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20. Hypoxic pulmonary vasoconstriction, carotid body function and erythropoietin production in adult rats perinatally exposed to hyperoxia
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Prieto Lloret, Jesús, Ramírez Arroyo, María, Olea Fraile, Elena, Moral Sanz, Javier, Cogolludo Torralba, Ángel, Castañeda, Javier, Yubero Benito, Sara, Agapito Serrano, María Teresa, Gómez Niño, María Ángeles, Rocher Martín, María Asunción, Rigual Bonastre, Ricardo Jaime, Obeso Cáceres, Ana María de la Luz, Pérez Vizcaíno, Francisco, and González, Constancio
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Carotid Body ,Vasoconstricción ,Hyperoxia ,Pulmonary Artery ,Antioxidants ,Carotid body ,Pregnancy ,Vasoconstriction ,Eritropoyetina ,Animals ,Hipoxia ,Female ,Rats, Wistar ,Cuerpo carotídeo ,Hypoxia ,Erythropoietin - Abstract
Producción Científica, Adult mammalians possess three cell systems that are activated by acute bodily hypoxia: pulmonary artery smooth muscle cells (PASMC), carotid body chemoreceptor cells (CBCC) and erythropoietin (EPO)-producing cells. In rats, chronic perinatal hyperoxia causes permanent carotid body (CB) atrophy and functional alterations of surviving CBCC. There are no studies on PASMC or EPO-producing cells. Our aim is to define possible long-lasting functional changes in PASMC or EPO-producing cells (measured as EPO plasma levels) and, further, to analyse CBCC functional alterations. We used 3- to 4-month-old rats born and reared in a normal atmosphere or exposed to perinatal hyperoxia (55–60% O2 for the last 5–6 days of pregnancy and 4 weeks after birth). Perinatal hyperoxia causes an almost complete loss of hypoxic pulmonary vasoconstriction (HPV), which was correlated with lung oxidative status in early postnatal life and prevented by antioxidant supplementation in the diet. O2-sensitivity of K+ currents in the PASMC of hyperoxic animals is normal, indicating that their inhibition is not sufficient to trigger HPV. Perinatal hyperoxia also abrogated responses elicited by hypoxia on catecholamine and cAMP metabolism in the CB. An increase in EPO plasma levels elicited by hypoxia was identical in hyperoxic and control animals, implying a normal functioning of EPO-producing cells. The loss of HPV observed in adult rats and caused by perinatal hyperoxia, comparable to oxygen therapy in premature infants, might represent a previously unrecognized complication of such a medical intervention capable of aggravating medical conditions such as regional pneumonias, atelectases or general anaesthesia in adult life., Ministerio de Economía, Industria y Competitividad (grants BFU2012-37459, SAF2011-28150 and SAF2010-22066-C02-02), Instituto de Salud Carlos III (grant CIBER CB06/06/0050)
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- 2015
21. Activation of PPARβ/δ prevents hyperglycaemia-induced impairment of Kv7 channels and cAMP-mediated relaxation in rat coronary arteries
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Morales-Cano, Daniel, primary, Moreno, Laura, additional, Barreira, Bianca, additional, Briones, Ana M., additional, Pandolfi, Rachele, additional, Moral-Sanz, Javier, additional, Callejo, Maria, additional, Mondejar-Parreño, Gema, additional, Cortijo, Julio, additional, Salaices, Mercedes, additional, Duarte, Juan, additional, Perez-Vizcaino, Francisco, additional, and Cogolludo, Angel, additional
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- 2016
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22. The emerging role of AMPK in the regulation of breathing and oxygen supply
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Evans, A. Mark, primary, Mahmoud, Amira D., additional, Moral-Sanz, Javier, additional, and Hartmann, Sandy, additional
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- 2016
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23. AMP‐activated protein kinase inhibits Kv1.5 channel currents of pulmonary arterial myocytes in response to hypoxia and inhibition of mitochondrial oxidative phosphorylation
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Moral‐Sanz, Javier, primary, Mahmoud, Amira D., additional, Ross, Fiona A., additional, Eldstrom, Jodene, additional, Fedida, David, additional, Hardie, D. Grahame, additional, and Evans, A. Mark, additional
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- 2016
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24. Microparticles induce pulmonary artery contraction through activation of acid sphingomyelinase and inhibition of Kv currents
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Moral-Sanz, Javier, Barreira, Bianca, Moreno, L., Morales-Cano, Daniel, Soleti, Raffaella, Grolleau, Françoise, Andriantsitohaina, Ramaroson, Cogolludo, Angel, Martinez, Maria Carmen, Perez-Vizcaino, Francisco, Stress Oxydant et Pathologies Métaboliques (SOPAM), and Université d'Angers (UA)-Institut National de la Santé et de la Recherche Médicale (INSERM)
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[SDV]Life Sciences [q-bio] ,ComputingMilieux_MISCELLANEOUS - Abstract
National audience
- Published
- 2013
25. Alteraciones vasculares pulmonares e hipertensión pulmonar en modelos de diabetes
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Moral Sanz, Javier, Pérez Vizcaíno, Francisco, and Cogolludo Torralba, Ángel
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Endocrinología - Abstract
La hipertensión plumonar (HP) es un síndrome caracterizado por una elevación mantenida en la presión arterial pulmonar media por encima de 25 mm Hg en reposo. Se trata de una enfermedad con una compleja fisiopatología y de etiología multifactorial. Se caracteriza por un aumento de la resistencia vascular pulmonar y vasoconstricción de las AP, una excesiva proliferación de las CMLV de las AP y remodelado vascular pulmonar, así como con procesos trombóticos a nivel pulmonar. La diabetes es una enfermedad metabólica con repercusión multiorgánica, caracterizada por hiperglucemia y alteraciones en la producción y/o acción de la insulina. En la actualidad se calcula que afecta a un 5% de la población mundial y es considerada la pandemia del siglo XXI. Las alteraciones vasculares generadas por la diabetes han sido ampliamente estudiadas a nivel sistémico. Sin embargo, sus efectos a nivel pulmonar permanecen sin caracterizar. Recientemente se han publicado datos epidemiológicos que relacionan la diabetes con la HP, pero no se disponen de evidencias experimentales que apoyen la relación entre ambas patologías. Por ello, es necesario caracterizar las alteraciones pulmonares originadas por la diabetes a nivel pulmonar, así como profundizar en el estudio de aspectos funcionales, histológicos y moleculares que relacionen esta patología metabólica con la HP. La hipótesis de esta Tesis Doctoral es que la diabetes mellitus podría ser un factor de riesgo que predispone y acelera el desarrollo de HP, induciendo de manera temprana las alteraciones funcionales, histológicas y moleculares características de la HP. El objetivo general de esta Tesis Doctoral es la caracterización de las alteraciones pulmonares desarrolladas en la diabetes tipo 1 y en la resistencia a la insulina, profundizando en el estudio de marcadores característicos de la HP con la intención de aportar evidencias experimentales que permitan determinar la posible relación entre la diabetes y la HP. El objetivo general se desglosa en los objetivos concretos que se detallan a continuación. [ABSTRACT]Pulmonary hypertension (PH) is a progressive disease of poor prognosis defined by an increased mean pulmonary artery pressure (mPAP) over 25 mmHg at rest. Additionally, the sustained elevation of the PAP leads to right ventricle hypertrophy. In its most aggressive forms like pulmonary arterial hypertension (PAH) it leads to heart failure and death in approximately 70% of patients 5 years after diagnosis (Laurenço et al., 2011). PAH is characterized by an increased pulmonary vascular resistance as a consequence of vasoconstriction of pulmonary arteries (PA), vascular smooth muscle cell and endothelial cell proliferation leading to PA remodelling and/or thrombosis in situ. Furthermore, PAH has a complex physiopathology unlikely to be explained by a single factor or gene mutation (Rabinovitch, 2008). Thus several factors tightly related to PAH in patients and animal models have been described such as mutations or down-regulation of bone morphogenetic protein receptor 2 (BMPR2), PA endothelial dysfunction, lung inflammation, reduced KV current density in PA smooth muscle cells (PASMC) associated to mutations or down-regulation of KV 1.5 channels, as well as an imbalance between circulating vasoconstrictor and vasodilator agents (Humbert et al., 2004; Mandegar et al., 2004; Chan and Loscalzo, 2008; Morrell et al., 2009; Simonneau et al., 2009; Remillard et al., 2007)...
- Published
- 2012
26. AMP‐activated Protein Kinase is Necessary for Cardiorespiratory Adjustments during Hypoxia
- Author
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Lewis, Sophronia, primary, Moral‐Sanz, Javier, additional, and Evans, A, additional
- Published
- 2015
- Full Text
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27. The Flavonoid Quercetin Reverses Pulmonary Hypertension in Rats
- Author
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Morales-Cano, Daniel, primary, Menendez, Carmen, additional, Moreno, Enrique, additional, Moral-Sanz, Javier, additional, Barreira, Bianca, additional, Galindo, Pilar, additional, Pandolfi, Rachele, additional, Jimenez, Rosario, additional, Moreno, Laura, additional, Cogolludo, Angel, additional, Duarte, Juan, additional, and Perez-Vizcaino, Francisco, additional
- Published
- 2014
- Full Text
- View/download PDF
28. Pulmonary Vascular Function in Insulin Resistance and Diabetes
- Author
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Moral-Sanz, Javier, primary, Moreno, Laura, additional, Cogolludo, Angel, additional, and Perez-Vizcaino, Francisco, additional
- Published
- 2014
- Full Text
- View/download PDF
29. Ceramide Mediates Acute Oxygen Sensing in Vascular Tissues
- Author
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Moreno, Laura, primary, Moral-Sanz, Javier, additional, Morales-Cano, Daniel, additional, Barreira, Bianca, additional, Moreno, Enrique, additional, Ferrarini, Alessia, additional, Pandolfi, Rachele, additional, Ruperez, Francisco J., additional, Cortijo, Julio, additional, Sanchez-Luna, Manuel, additional, Villamor, Eduardo, additional, Perez-Vizcaino, Francisco, additional, and Cogolludo, Angel, additional
- Published
- 2014
- Full Text
- View/download PDF
30. Pulmonary Vascular Dysfunction Induced by High Tidal Volume Mechanical Ventilation*
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Menendez, Carmen, primary, Martinez-Caro, Leticia, additional, Moreno, Laura, additional, Nin, Nicolas, additional, Moral-Sanz, Javier, additional, Morales, Daniel, additional, Cogolludo, Angel, additional, Esteban, Andres, additional, Lorente, Jose A., additional, and Perez-Vizcaino, Francisco, additional
- Published
- 2013
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31. AMP-activated protein kinase inhibits Kv1.5 channel currents of pulmonary arterial myocytes in response to hypoxia and inhibition of mitochondrial oxidative phosphorylation.
- Author
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Moral‐Sanz, Javier, Mahmoud, Amira D., Ross, Fiona A., Eldstrom, Jodene, Fedida, David, Hardie, D. Grahame, and Evans, A. Mark
- Subjects
- *
PROTEIN kinases , *PULMONARY artery , *MUSCLE cells , *HYPOXEMIA , *OXIDATIVE phosphorylation - Abstract
Key points Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage-gated potassium channels (Kv) in pulmonary arterial smooth muscle by hypoxia, although the precise molecular mechanisms have been unclear., AMP-activated protein kinase (AMPK) has been proposed to couple inhibition of mitochondrial metabolism by hypoxia to acute hypoxic pulmonary vasoconstriction and progression of pulmonary hypertension., Inhibition of complex I of the mitochondrial electron transport chain activated AMPK and inhibited Kv1.5 channels in pulmonary arterial myocytes., AMPK activation by 5-aminoimidazole-4-carboxamide riboside, A769662 or C13 attenuated Kv1.5 currents in pulmonary arterial myocytes, and this effect was non-additive with respect to Kv1.5 inhibition by hypoxia and mitochondrial poisons., Recombinant AMPK phosphorylated recombinant human Kv1.5 channels in cell-free assays, and inhibited K+ currents when introduced into HEK 293 cells stably expressing Kv1.5., These results suggest that AMPK is the primary mediator of reductions in Kv1.5 channels following inhibition of mitochondrial oxidative phosphorylation during hypoxia and by mitochondrial poisons., Abstract Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage-gated potassium channels (Kv) in pulmonary arterial smooth muscle cells that is mediated by the inhibition of mitochondrial oxidative phosphorylation. We sought to determine the role in this process of the AMP-activated protein kinase (AMPK), which is intimately coupled to mitochondrial function due to its activation by LKB1-dependent phosphorylation in response to increases in the cellular AMP:ATP and/or ADP:ATP ratios. Inhibition of complex I of the mitochondrial electron transport chain using phenformin activated AMPK and inhibited Kv currents in pulmonary arterial myocytes, consistent with previously reported effects of mitochondrial inhibitors. Myocyte Kv currents were also markedly inhibited upon AMPK activation by A769662, 5-aminoimidazole-4-carboxamide riboside and C13 and by intracellular dialysis from a patch-pipette of activated (thiophosphorylated) recombinant AMPK heterotrimers (α2β2γ1 or α1β1γ1). Hypoxia and inhibitors of mitochondrial oxidative phosphorylation reduced AMPK-sensitive K+ currents, which were also blocked by the selective Kv1.5 channel inhibitor diphenyl phosphine oxide-1 but unaffected by the presence of the BKCa channel blocker paxilline. Moreover, recombinant human Kv1.5 channels were phosphorylated by AMPK in cell-free assays, and K+ currents carried by Kv1.5 stably expressed in HEK 293 cells were inhibited by intracellular dialysis of AMPK heterotrimers and by A769662, the effects of which were blocked by compound C. We conclude that AMPK mediates Kv channel inhibition by hypoxia in pulmonary arterial myocytes, at least in part, through phosphorylation of Kv1.5 and/or an associated protein. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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- View/download PDF
32. Pulmonary arterial dysfunction in insulin resistant obese Zucker rats
- Author
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Moral-Sanz, Javier, primary, Menendez, Carmen, additional, Moreno, Laura, additional, Moreno, Enrique, additional, Cogolludo, Angel, additional, and Perez-Vizcaino, Francisco, additional
- Published
- 2011
- Full Text
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33. Neutral sphingomyelinase, NADPH oxidase and reactive oxygen species. Role in acute hypoxic pulmonary vasoconstriction
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Frazziano, Giovanna, primary, Moreno, Laura, additional, Moral-Sanz, Javier, additional, Menendez, Carmen, additional, Escolano, Lucía, additional, Gonzalez, Constancio, additional, Villamor, Eduardo, additional, Alvarez-Sala, Jose Luis, additional, Cogolludo, Angel L., additional, and Perez-Vizcaino, Francisco, additional
- Published
- 2011
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- View/download PDF
34. Ceramide inhibits Kv currents and contributes to TP-receptor-induced vasoconstriction in rat and human pulmonary arteries
- Author
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Moral-Sanz, Javier, primary, Gonzalez, Teresa, additional, Menendez, Carmen, additional, David, Miren, additional, Moreno, Laura, additional, Macias, Alvaro, additional, Cortijo, Julio, additional, Valenzuela, Carmen, additional, Perez-Vizcaino, Francisco, additional, and Cogolludo, Angel, additional
- Published
- 2011
- Full Text
- View/download PDF
35. Type 1 Diabetes-Induced Hyper-Responsiveness to 5-Hydroxytryptamine in Rat Pulmonary Arteries via Oxidative Stress and Induction of Cyclooxygenase-2
- Author
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Lopez-Lopez, Jose G., primary, Moral-Sanz, Javier, additional, Frazziano, Giovanna, additional, Gomez-Villalobos, Maria J., additional, Moreno, Laura, additional, Menendez, Carmen, additional, Flores-Hernandez, Jorge, additional, Lorente, Jose A., additional, Cogolludo, Angel, additional, and Perez-Vizcaino, Francisco, additional
- Published
- 2011
- Full Text
- View/download PDF
36. Celecoxib Blocks Cardiac Kv1.5, Kv4.3 and Kv7.1 (KCNQ1) Channels. Effects on Cardiac Action Potentials
- Author
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Macias, Alvaro, primary, Moreno, Cristina, additional, Moral-Sanz, Javier, additional, Cogolludo, Angel, additional, David, Miren, additional, Alemanni, Matteo, additional, Perez-Vizcaino, Francisco, additional, Zaza, Antonio, additional, Valenzuela, Carmen, additional, and Gonzalez, Teresa, additional
- Published
- 2011
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- View/download PDF
37. Celecoxib blocks cardiac Kv1.5, Kv4.3 and Kv7.1 (KCNQ1) channels
- Author
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Macías, Álvaro, primary, Moreno, Cristina, additional, Moral-Sanz, Javier, additional, Cogolludo, Ángel, additional, David, Miren, additional, Alemanni, Matteo, additional, Pérez-Vizcaíno, Francisco, additional, Zaza, Antonio, additional, Valenzuela, Carmen, additional, and González, Teresa, additional
- Published
- 2010
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- View/download PDF
38. Ceramide inhibits Kv currents and contributes to TP-receptor-induced vasoconstriction in rat and human pulmonary arteries.
- Author
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Moral-Sanz, Javier, Gonzalez, Teresa, Menendez, Carmen, David, Miren, Moreno, Laura, Macias, Alvaro, Cortijo, Julio, Valenzuela, Carmen, Perez-Vizcaino, Francisco, and Cogolludo, Angel
- Subjects
- *
CERAMIDES , *PULMONARY artery , *VASOCONSTRICTION , *PULMONARY circulation , *SMOOTH muscle - Abstract
Neutral sphingomyelinase (nSMase)-derived ceramide has been proposed as a mediator of hypoxic pulmonary vasoconstriction (HPV), a specific response of the pulmonary circulation. Voltage-gated K+ (Kv) channels are modulated by numerous vasoactive factors, including hypoxia, and their inhibition has been involved in HPV. Herein, we have analyzed the effects of ceramide on Kv currents and contractility in rat pulmonary arteries (PA) and in mesenteric arteries (MA). The ceramide analog C6-ceramide inhibited Kv currents in PA smooth muscle cells (PASMC). Similar effects were obtained after the addition of bacterial sphingomyelinase (SMase), indicating a role for endogenous ceramide in Kv channel regulation. Kv current was reduced by stromatoxin and diphenylphosphine oxide-1 (DPO-1), selective inhibitors of Kv2.1 and Kv1.5 channels, respectively. The inhibitory effect of ceramide was still present in the presence of stromatoxin or DPO-1, suggesting that this sphingolipid inhibited both components of the native Kv current. Accordingly, ceramide inhibited Kv1.5 and Kv2.1 channels expressed in Ltk-cells. Ceramide-induced effects were reduced in human embryonic kidney 293 cells expressing Kv1.5 channels but not the regulatory subunit Kvβ2.1. The nSMase inhibitor GW4869 reduced the thromboxane-endoperoxide receptor agonist U46619-induced, but not endothelin-1-induced pulmonary vasoconstriction that was partly restored after addition of exogenous ceramide. The PKC-ζ pseudosubstrate inhibitor (PKCζ-PI) inhibited the Kv inhibitory and contractile effects of ceramide. In MA ceramide had no effect on Kv currents and GW4869 did not affect U46619-induced contraction. The effects of SMase were also observed in human PA. These results suggest that ceramide represents a crucial signaling mediator in the pulmonary vasculature. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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- View/download PDF
39. Maturation of O2 sensing and signaling in the chicken ductus arteriosus.
- Author
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Cogolludo, Angel L., Moral-Sanz, Javier, van der Sterren, Saskia, Frazziano, Giovanna, van Cleef, Anne N. H., Menéndez, Carmen, Zoer, Bea, Moreno, Enrique, Roman, Angela, Pérez-Vizcaino, Francisco, and Villamor, Eduardo
- Subjects
- *
DUCTUS arteriosus , *CHICKEN diseases , *CELLULAR signal transduction , *ELECTRON transport , *PROTEIN kinases , *ACTIVE oxygen in the body , *GENETICS , *DISEASES - Abstract
The increase in O2 tension after birth is a major factor stimulating ductus arteriosus (DA) constriction and closure. Here we. studied the role of the mitochondrial electron transport chain (ETC) as sensor, H2O2 as mediator, and voltage-gated potassium (Ky) channels and Rho kinase as effectors of O2-induced contraction in the chicken DA during fetal development. Switching from 0% to 21% O2 contracted the pulmonary side of the mature DA (mature pDA) but had no effect in immature pDA and relaxed the aortic side of the mature DA (mature aDA). This contraction of the pDA was attenuated by inhibitors of the mitochondrial ETC and by the H2O2 scavenger polyethylene glycol (PEG)-catalase. Moreover, O2 increased reactive oxygen species (ROS) production, measured with the fluorescent probes dihydroethidium and 2',7'-dichlorofluorescein, only in mature pDA. The H2O2 analog t-butyl-hydroperoxide mimicked the responses to O2 in the three vessels. In contrast to immature pDA cells, mature pDA cells exhibited high-amplitude O2-sensitive potassium currents. The Kv channel blocker 4-aminopyridine prevented the current inhibition elicited by O2. The L-type Ca2+ (CaL) channel blocker nifedipine and the Rho kinase inhibitors Y-27632 and hydroxyfasudil induced a similar relaxation when mature pDA were stimulated with O2 or H2O2. Moreover, the sensitivity to these drugs increased with maturation. Our results indicate the presence of a common mechanism for O2 sensing/signaling in mammalian and nonmammalian DA and favor the idea that, rather than a single mechanism, a parallel maturation of the sensor and effectors is critical for O2 sensitivity appearance during development. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
40. Hypoxia-induced contraction of chicken embryo mesenteric arteries: mechanisms and developmental changes.
- Author
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Brinks L, Moonen RM, Moral-Sanz J, Barreira B, Kessels L, Perez-Vizcaino F, Cogolludo A, and Villamor E
- Subjects
- Animals, Chick Embryo, Embryonic Development, Muscle Contraction, Hypoxia physiopathology, Mesenteric Arteries embryology, Mesenteric Arteries physiopathology, Muscle, Smooth, Vascular embryology, Muscle, Smooth, Vascular physiopathology, Vasoconstriction
- Abstract
The fetal cardiovascular responses to acute hypoxia include a redistribution of the cardiac output toward the heart and the brain at the expense of other organs, such as the intestine. We hypothesized that hypoxia exerts a direct effect on the mesenteric artery (MA) that may contribute to this response. Using wire myography, we investigated the response to hypoxia (Po
2 ~2.5 kPa for 20 min) of isolated MAs from 15- to 21-day chicken embryos (E15, E19, E21), and 1- to 45-day-old chickens (P1, P3, P14, P45). Agonist-induced pretone or an intact endothelium were not required to obtain a consistent and reproducible response to hypoxia, which showed a pattern of initial rapid phasic contraction followed by a sustained tonic contraction. Phasic contraction was reduced by elimination of extracellular Ca2+ or by presence of the neurotoxin tetrodotoxin, the α1 -adrenoceptor antagonist prazosin, or inhibitors of L-type voltage-gated Ca2+ channels (nifedipine), mitochondrial electron transport chain (rotenone and antimycin A), and NADPH oxidase (VAS2870). The Rho-kinase inhibitor Y27632 impaired both phasic and tonic contraction and, when combined with elimination of extracellular Ca2+ , hypoxia-induced contraction was virtually abolished. Hypoxic MA contraction was absent at E15 but present from E19 and increased toward the first days posthatching. It then decreased during the first weeks of life and P45 MAs were unable to sustain hypoxia-induced contraction over time. In conclusion, the results of the present study demonstrate that hypoxic vasoconstriction is an intrinsic feature of chicken MA vascular smooth muscle cells during late embryogenesis and the perinatal period., (Copyright © 2016 the American Physiological Society.)- Published
- 2016
- Full Text
- View/download PDF
41. AMP-activated protein kinase inhibits Kv 1.5 channel currents of pulmonary arterial myocytes in response to hypoxia and inhibition of mitochondrial oxidative phosphorylation.
- Author
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Moral-Sanz J, Mahmoud AD, Ross FA, Eldstrom J, Fedida D, Hardie DG, and Evans AM
- Subjects
- Animals, HEK293 Cells, Humans, Male, Oxidative Phosphorylation, Pulmonary Artery cytology, Rats, Sprague-Dawley, AMP-Activated Protein Kinases physiology, Hypoxia physiopathology, Kv1.5 Potassium Channel physiology, Mitochondria metabolism, Muscle Cells physiology
- Abstract
Key Points: Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage-gated potassium channels (Kv ) in pulmonary arterial smooth muscle by hypoxia, although the precise molecular mechanisms have been unclear. AMP-activated protein kinase (AMPK) has been proposed to couple inhibition of mitochondrial metabolism by hypoxia to acute hypoxic pulmonary vasoconstriction and progression of pulmonary hypertension. Inhibition of complex I of the mitochondrial electron transport chain activated AMPK and inhibited Kv 1.5 channels in pulmonary arterial myocytes. AMPK activation by 5-aminoimidazole-4-carboxamide riboside, A769662 or C13 attenuated Kv 1.5 currents in pulmonary arterial myocytes, and this effect was non-additive with respect to Kv 1.5 inhibition by hypoxia and mitochondrial poisons. Recombinant AMPK phosphorylated recombinant human Kv 1.5 channels in cell-free assays, and inhibited K(+) currents when introduced into HEK 293 cells stably expressing Kv 1.5. These results suggest that AMPK is the primary mediator of reductions in Kv 1.5 channels following inhibition of mitochondrial oxidative phosphorylation during hypoxia and by mitochondrial poisons., Abstract: Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage-gated potassium channels (Kv ) in pulmonary arterial smooth muscle cells that is mediated by the inhibition of mitochondrial oxidative phosphorylation. We sought to determine the role in this process of the AMP-activated protein kinase (AMPK), which is intimately coupled to mitochondrial function due to its activation by LKB1-dependent phosphorylation in response to increases in the cellular AMP:ATP and/or ADP:ATP ratios. Inhibition of complex I of the mitochondrial electron transport chain using phenformin activated AMPK and inhibited Kv currents in pulmonary arterial myocytes, consistent with previously reported effects of mitochondrial inhibitors. Myocyte Kv currents were also markedly inhibited upon AMPK activation by A769662, 5-aminoimidazole-4-carboxamide riboside and C13 and by intracellular dialysis from a patch-pipette of activated (thiophosphorylated) recombinant AMPK heterotrimers (α2β2γ1 or α1β1γ1). Hypoxia and inhibitors of mitochondrial oxidative phosphorylation reduced AMPK-sensitive K(+) currents, which were also blocked by the selective Kv 1.5 channel inhibitor diphenyl phosphine oxide-1 but unaffected by the presence of the BKCa channel blocker paxilline. Moreover, recombinant human Kv 1.5 channels were phosphorylated by AMPK in cell-free assays, and K(+) currents carried by Kv 1.5 stably expressed in HEK 293 cells were inhibited by intracellular dialysis of AMPK heterotrimers and by A769662, the effects of which were blocked by compound C. We conclude that AMPK mediates Kv channel inhibition by hypoxia in pulmonary arterial myocytes, at least in part, through phosphorylation of Kv 1.5 and/or an associated protein., (© 2016 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)
- Published
- 2016
- Full Text
- View/download PDF
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