Pour savoir comment effectuer et gérer un dépôt de document, consultez le « Guide abrégé – Dépôt de documents » sur le site Web de la Bibliothèque. Pour toute question, écrivez à corpus@ulaval.ca.
 

Personne :
Roy, Caroline

En cours de chargement...
Photo de profil

Adresse électronique

Date de naissance

Projets de recherche

Structures organisationnelles

Fonction

Nom de famille

Roy

Prénom

Caroline

Affiliation

Université Laval. Département de microbiologie-infectiologie et d'immunologie

ISNI

ORCID

Identifiant Canadiana

ncf13705806

person.page.name

Résultats de recherche

Voici les éléments 1 - 10 sur 13
  • PublicationAccès libre
    Vasopeptidase-activated latent ligands of the histamine receptor-1
    (Elsevier, 2013-11-01) Gera, Lajos; Roy, Caroline; Marceau, François; Charest-Morin??, Xavier
    Whether peptidases present in vascular cells can activate prodrugs active on vascular cells has been tested with 2 potential latent ligands of the histamine H1 receptor (H1R). First, a peptide consisting of the antihistamine cetirizine (CTZ) condensed at the N-terminus of ε-aminocaproyl-bradykinin (εACA-BK) was evaluated for an antihistamine activity that could be revealed by degradation of the peptide part of the molecule. CTZ-εACA-BK had a submicromolar affinity for the BK B2 receptor (B2R; IC50 of 590 nM, [(3)H]BK binding competition), but a non-negligible affinity for the human H1 receptor (H1R; IC50 of 11 μM for [(3)H]pyrilamine binding). In the human isolated umbilical vein, a system where both endogenous B2R and H1R mediate strong contractions, CTZ-εACA-BK exerted mild antagonist effects on histamine-induced contraction that were not modified by omapatrilat or by a B2R antagonist that prevents endocytosis of the BK conjugate. Cells expressing recombinant ACE or B2R incubated with CTZ-εACA-BK did not release a competitor of [(3)H]pyrilamine binding to H1Rs. Thus, there is no evidence that CTZ-εACA-BK can release free cetirizine in biological environments. The second prodrug was a blocked agonist, L-alanyl-histamine, potentially activated by aminopeptidase N (APN). This compound did not compete for [(3)H]pyrilamine binding to H1Rs. The human umbilical vein contractility assay responded to L-alanyl-histamine (EC50 54.7 μM), but the APN inhibitor amastatin massively (17-fold) reduced its apparent potency. Amastatin did not influence the potency of histamine as a contractile agent. One of the 2 tested latent H1R ligands, L-alanyl-histamine, supported the feasibility of pro-drug activation by vascular ectopeptidases
  • PublicationAccès libre
    An in vitro reconstitution system to address the mechanism of the vascular expression of the bradykinin B1 receptor in response to angiotensin converting enzyme inhibition
    (Elsevier Science, 2011-10-02) Roy, Caroline; Marceau, Émilie; Gera, Lajos; Marceau, François
    The expression of the bradykinin (BK) B1 receptor (B1R), lacking in normal vascular tissues, is induced following innate immune system activation and chronic blockade of angiotensin converting enzyme (ACE). To identify cytokine-dependent or -independent mechanisms for the latter phenomenon, the ACE inhibitor enalaprilat and several peptides potentiated in vivo by ACE blockade were applied either directly to human umbilical artery smooth muscle cells (hUA-SMCs) or to differentiated monoblastoid U937 cells to produce a conditioned medium (CM) that was later transferred to hUA-SMCs. A phagocyte stimulant, lipopolysaccharide, did not upregulate B1R, measured using [3H]Lys-des-Arg9-BK binding, or translocate NF-κB to the nuclei if applied directly to the hUA-SMCs. However, the CM of lipopolysaccharide-stimulated U937 cells was active in these respects (effects inhibited by etanercept and correlated to TNF-α presence in the CM). A peptidase-resistant B1R agonist had no significant direct or indirect acute effect (4 h) on B1R expression, but repeated hUA-SMC stimulations over 40 h were stimulatory in the absence of NF-κB activation. Other peptides regulated by ACE or enalaprilat did not directly or indirectly stimulate B1R expression. The reconstitution system supports the rapid cytokine-dependent vascular induction of B1Rs and a slow “autoregulatory” one potentially relevant for the ACE blockade effect.
  • PublicationAccès libre
    Met-Lys-bradykinin-Ser-Ser, a peptide produced by the neutrophil from kininogen, is metabolically activated by angiotensin converting enzyme in vascular tissue
    (Academic Press, 2011-08-11) Gera, Lajos; Roy, Caroline; Bawolak, Marie-Thérèse; Marceau, François; Bouthillier, Johanne; Adam, Albert
    Bradykinin (BK) is a vasoactive nonapeptide cleaved from circulating kininogens and that is degraded by angiotensin converting enzyme (ACE). It has been reported that the PR3 protease from human neutrophil releases an alternate peptide of 13 amino acids, Met-Lys-BK-Ser-Ser, from high molecular weight kininogen. We have studied vascular actions of this kinin. Its affinity for recombinant B1 and B2 receptors is very low, as assessed by the binding competition of [3H]Lys-des-Arg9-BK and [3H]BK, respectively, but Met-Lys-BK-Ser-Ser effectively displaced a fraction of [3H]enalaprilat binding to recombinant ACE. Mutant recombinant ACE constructions revealed that affinity gap between BK and Met-Lys-BK-Ser-Ser is larger for the N-terminal catalytic site than for the C-terminal one, based on competition for the substrate Abz-Phe-Arg-Lys(Dnp)-Pro-OH in an enzymatic assay. Met-Lys-BK-Ser-Ser is a low potency stimulant of the rabbit aorta (bioassay for B1 receptors), but the human isolated umbilical vein, a contractile bioassay for the B2 receptors, responded to Met-Lys-BK-Ser-Ser more than expected from the radioligand binding assay, this agonist being ∼30-fold less potent than BK in the vein. Venous tissue treatment with the ACE inhibitor enalaprilat reduced the apparent potency of Met-Lys-BK-Ser-Ser by 15-fold, while not affecting that of BK. In the rabbit isolated jugular vein, Met-Lys-BK-Ser-Ser is nearly as potent as BK as a contractile stimulant of endogenous B2 receptors (EC50 values of 16.3 and 10.5 nM, respectively), but enalaprilat reduced the potency of Met-Lys-BK-Ser-Ser 13-fold while increasing that of BK 5.3-fold. In vascular tissue, ACE assumes a paradoxical activating role for Met-Lys-BK-Ser-Ser.
  • PublicationRestreint
    Assessment of cation trapping by cellular acidic compartments
    (Academic Press, 2013-12-17) Roy, Caroline; Marceau, François; Bouthillier, Johanne; P. Michael, Conn
    All nucleated cells, from yeast to animal cells, concentrate cationic chemicals (weak bases with a pKa ~8-10) into acidic cell compartments (low retro-diffusion under a protonated form at low pH = ion trapping). The proton pump vacuolar (V)-ATPase is the driving force of this pseudotransport that concerns acidic organelles (mainly late endosomes and lysosomes). The latter rapidly become swollen (osmotic vacuolization) and macroautophagic. Cation concentration in cells is not proven to involve membrane transporters, but is prevented or reversed by inhibitors of V-ATPase, such as bafilomycin A1. Lipophilicity is a major determinant of the apparent affinity of this pseudotransport because simple diffusion of the uncharged form supports it. Quinacrine is a formerly used anti-parasitic drug that is intensely fluorescent, lipophilic and a tertiary amine. The drug, at micromolar concentrations, is proposed as a superior probe for assessing cation trapping by cellular acidic compartments, being readily quantified using fluorometry in cell extracts and analyzed using microscopy and cytofluorometry (fluorescence settings for fluorescein being applicable). Further, cells respond to micromolar levels of quinacrine by autophagic accumulation (e.g., accumulation of the activated macroautophagic effector LC3 II, immunoblots), an objective and universal response to sequestered amines.
  • PublicationAccès libre
    High affinity capture and concentration of quinacrine in polymormonuclear neutrophils via vacuolar ATPase-mediated ion trapping : comparison with other peripheral blood leukocytes and implications for the distribution of cationic drugs
    (Elsevier, 2013-04-17) Roy, Caroline; Marceau, François; Fernandes, Maria J.; Gagné, Valérie
    Many cationic drugs are concentrated in acidic cell compartments due to low retro-diffusion of the protonated molecule (ion trapping), with an ensuing vacuolar and autophagic cytopathology. In solid tissues, there is evidence that phagocytic cells, e.g., histiocytes, preferentially concentrate cationic drugs. We hypothesized that peripheral blood leukocytes could differentially take up a fluorescent model cation, quinacrine, depending on their phagocytic competence. Quinacrine transport parameters were determined in purified or total leukocyte suspensions at 37 °C. Purified polymorphonuclear leukocytes (PMNLs, essentially neutrophils) exhibited a quinacrine uptake velocity inferior to that of lymphocytes, but a consistently higher affinity (apparent KM 1.1 vs. 6.3 μM, respectively). However, the vacuolar (V)-ATPase inhibitor bafilomycin A1 prevented quinacrine transport or initiated its release in either cell type. PMNLs capture most of the quinacrine added at low concentrations to fresh peripheral blood leukocytes compared with lymphocytes and monocytes (cytofluorometry). Accumulation of the autophagy marker LC3-II occurred rapidly and at low drug concentrations in quinacrine-treated PMNLs (significant at ≥2.5 μM, ≥2 h). Lymphocytes contained more LAMP1 than PMNLs, suggesting that the mass of lysosomes and late endosomes is a determinant of quinacrine uptake Vmax. PMNLs, however, exhibited the highest capacity for pinocytosis (uptake of fluorescent dextran into endosomes). The selectivity of quinacrine distribution in peripheral blood leukocytes may be determined by the collaboration of a non-concentrating plasma membrane transport mechanism, tentatively identified as pinocytosis in PMNLs, with V-ATPase-mediated concentration. Intracellular reservoirs of cationic drugs are a potential source of toxicity (e.g., loss of lysosomal function in phagocytes).
  • PublicationAccès libre
    Inhibitory effects of cytoskeleton disrupting drugs and GDP-locked Rab mutants on bradykinin B2 receptor cycling
    (Academic Press, 2013-05-01) Fortin, Sébastien; Roy, Caroline; Marceau, François; Lodge, Robert; Gera, Lajos; C. Gaudreault, René.; Charest-Morin, Xavier
    The bradykinin (BK) B2 receptor (B2R) is G protein coupled and phosphorylated upon agonist stimulation; its endocytosis and recycling are documented. We assessed the effect of drugs that affect the cytoskeleton on B2R cycling. These drugs were targeted to tubulin (paclitaxel, or the novel combretastatin A-4 mimetic 3,4,5-trimethoxyphenyl-4-(2-oxoimidazolidin-1-yl)benzenesulfonate [IMZ-602]) and actin (cytochalasin D). Tubulin ligands did not alter agonist-induced receptor endocytosis, as shown using antibodies reactive with myc-tagged B2Rs (microscopy, cytofluorometry), but rather reduced the progression of the ligand–receptor–β-arrestin complex from the cell periphery to the interior. The 3 fluorescent probes of this complex (B2R-green fluorescent protein [B2R-GFP], the fluorescent agonist fluorescein-5-thiocarbamoyl-D-Arg-[Hyp3, Igl5, Oic7, Igl8]-BK and β-arrestin2–GFP) were condensed in punctuate structures that remained close to the cell surface in the presence of IMZ-602. Cytochalasin D selectively inhibited the recycling of endocytosed B2R-GFP (B2R-GFP imaging, [3H]BK binding). Dominant negative (GDP-locked)-Rab5 and -Rab11 reproduced the effects of inhibitors of tubulin and actin, respectively, on the cycling of B2R-GFP. GDP-locked-Rab4 also inhibited B2R-GFP recycling to the cell surface. Consistent with the displacement of cargo along specific cytoskeletal elements, Rab5-associated progression of the endocytosed BK B2R follows microtubules toward their (−) end, while its recycling progresses along actin fibers to the cell surface. However, tubulin ligands do not suppress the tested desensitization or resensitization mechanisms of the B2R
  • PublicationAccès libre
    Bifunctional ligands of the bradykinin B2 and B1 receptors : an exercise in peptide hormone plasticity
    (Elsevier, 2018-05-23) Bachelard, Hélène; Roy, Caroline; Bawolak, Marie-Thérèse; Fortin, Jean-Philippe.; Marceau, François; Morissette, Guillaume; Lajos, Gera; Charest-Morin, Xavier
    Kinins are the small and fragile hydrophilic peptides related to bradykinin (BK) and derived from circulating kininogens via the action of kallikreins. Kinins bind to the preformed and widely distributed B2 receptor (B2R) and to the inducible B1 receptor (B1R). B2Rs and B1Rs are related G protein coupled receptors that possess natural agonist ligands of nanomolar affinity (BK and Lys BK for B2Rs, Lys-des-Arg9-BK for B1R). Decades of structure-activity exploration have resulted in the production of peptide analogs that are antagonists, one of which is clinically used (the B2R antagonist icatibant), and also non-peptide ligands for both receptor subtypes. The modification of kinin receptor ligands has made them resistant to extracellular or endosomal peptidases and/or produced bifunctional ligands, defined as agonist or antagonist peptide ligands conjugated with a chemical fluorophore (emitting in the whole spectrum, from the infrared to the ultraviolet), a drug-like moiety, an epitope, an isotope chelator/carrier, a cleavable sequence (thus forming a pro-drug) and even a fused protein. Dual molecular targets for specific modified peptides may be a source of side effects or of medically exploitable benefits. Biotechnological protein ligands for either receptor subtype have been produced: they are enhanced green fluorescent protein or the engineered peroxidase APEX2 fused to an agonist kinin sequence at their C-terminal terminus. Antibodies endowed with pharmacological actions (agonist, antagonist) at B2R have been reported, though not monoclonal antibodies. These findings define classes of alternative ligands of the kinin receptor of potential therapeutic and diagnostic value.
  • PublicationAccès libre
    Nouveaux ligands du récepteur B₂ de la bradykinine : endocytose dirigée et catabolisme sélectif
    (2013) Roy, Caroline; Marceau, François
    Les récepteurs B₂ (RB₂) sont impliqués dans une multitude de réponses cellulaires notamment reliées à l’inflammation. Les RB₂ font partie du système kallikréine-kinine qui est en relation directe avec les composantes du système rénine-angiotensine. Une des composantes de ce dernier est l’enzyme de conversion de l’angiotensine (ECA) qui métabolise la bradykinine (BK) et la rend inactive. Un premier volet des travaux visait à étudier et caractériser de nouveaux agonistes du RB₂ qui sont prolongés en amino-terminal (N-terminal) ou conjugués à un épitope myc. Ces constructions révèlent de nouveaux outils d’imagerie cellulaire et permettent d’entrevoir la possibilité de pouvoir larguer un médicament conjugué aux ligands endogènes. Dans une seconde partie des travaux, un des agonistes prolongés en N-terminal, la cétirizine-ε-aminocaproyl-BK (CTZ-εACA-BK) et un peptide produit par le neutrophile humain (Met-Lys-BK-Ser-Ser) sont employés pour mettre à l’épreuve l’étendue du catabolisme de l’ECA. Seule Met-Lys-BK-Ser-Ser s’est révélée être un substrat fonctionnel de l’ECA.
  • PublicationAccès libre
    Bradykinin receptors : agonists, antagonists, expression, signaling and adaptation to sustained stimulation
    (2013-12-01) Fortin, Sébastien; Sabourin, Thierry; Roy, Caroline; Bawolak, Marie-Thérèse; Koumbadinga, Gérémy Abdull; Fortin, Jean-Philippe.; Marceau, François; Morissette, Guillaume; Lodge, Robert; C. Gaudreault, René.; Houle, Steeve.; Charest-Morin, Xavier; Bouthillier, Johanne; Gera, Lajos
    Bradykinin-related peptides, the kinins, are blood-derived peptides that stimulate 2 G protein–coupled receptors, the B1 and B2 receptors (B1R, B2R). The pharmacologic and molecular identities of these 2 receptor subtypes will be succinctly reviewed, with emphasis on drug development, receptor expression, signaling, and adaptation to persistent stimulation. Peptide and nonpeptide antagonists and fluorescent ligands have been produced for each receptor. The B2R is widely and constitutively expressed in mammalian tissues, whereas the B1R is mostly inducible under the effect of cytokines during infection and immunopathology. Both receptor subtypes mediate the vascular aspects of inflammation (vasodilation, edema formation). On this basis, icatibant, a peptide antagonist of the B2R, is approved in the management of hereditary angioedema attacks. Other clinical applications are still elusive despite the maturity of the medicinal chemistry efforts applied to kinin receptors. While both receptor subtypes are mainly coupled to the Gq protein and related second messengers, the B2R is temporarily desensitized by a cycle of phosphorylation/endocytosis followed by recycling, whereas the nonphosphorylable B1R is relatively resistant to desensitization and translocated to caveolae on activation.
  • PublicationAccès libre
    N-terminal extended conjugates of the agonists and antagonists of both bradykinin receptor subtypes : structure-activity relationship, cell imaging using ligands conjugated with fluorophores and prospect for functionally active cargoes
    (Elsevier, 2012-02-18) Gera, Lajos; Roy, Caroline; Bawolak, Marie-Thérèse; Marceau, François; Charest-Morin, Xavier
    Peptide agonists and antagonists of both bradykinin (BK) B1 and B2 receptors (B1R, B2R) are known to tolerate to a certain level N-terminal sequence extensions. Using this strategy, we produced and characterized the full set of fluorescent ligands by extending both agonists and antagonist peptides at both receptor subtypes with 5(6)-carboxyfluorescein (CF) and the ɛ-aminocaproyl (ɛ-ACA) optional spacer. Alternatively, kinin receptor ligands were extended with another carboxylic acid cargo (chlorambucil, biotinyl, pentafluorocinnamoyl, AlexaFluor-350 (AF350), ferrocenoyl, cetirizine) or with fluorescein isothiocyanate. N-terminal extension always reduced receptor affinity, more importantly for bulkier substituents and more so for the agonist version compared to the antagonist. This loss was generally alleviated by the presence of the spacer and modulated by the species of origin for the receptor. We report and review the pharmacological properties of these N-terminally extended peptides and the use of fluorophore-conjugated ligands in imaging of cell receptors and of angiotensin converting enzyme (ACE) in intact cells. Antagonists (B1R: B-10376: CF-ɛ-ACA-Lys-Lys-[Hyp3, CpG5, d-Tic7, CpG8]des-Arg9-BK; B2R: B-10380: CF-ɛ-ACA-d-Arg-[Hyp3, Igl5, d-Igl7, Oic8]-BK and fluorescein-5-thiocarbamoyl (FTC)-B-9430) label the plasma membrane of cells expressing the cognate receptors. The B2R agonists CF-ɛ-ACA-BK, AF350-ɛ-ACA-BK and FTC-B-9972 are found in endosomes and model the endosomal degradation of BK in a complementary manner. The uneven surface fluorescence associated to the B1R agonist B-10378 (CF-ɛ-ACA-Lys-des-Arg9-BK) is compatible with a particular form of agonist-induced receptor translocation. CF-ɛ-ACA-BK binds to the carboxydipeptidase ACE with an affinity identical to that of BK. Metal- or drug-containing cargoes further show the prospect of ligands that confer special signaling to kinin receptors.