showing 6 related works from this author
β-Adrenoceptors differentially regulate vascular tone and angiogenesis of rat aorta via ERK1/2 and p38
2014
β-Adrenoceptors (β-ARs) modulate ERK1/2 and p38 in different cells, but little is known about the contribution of these signaling pathways to the function of β-ARs in vascular tissue. Immunoblotting analysis of rat aortic rings, primary endothelial (ECs) and smooth muscle cells (SMCs) isolated from aorta showed that β-AR stimulation with isoprenaline activated p38 in aortic rings and in both cultured cell types, whereas it had a dual effect on ERK1/2 phosphorylation, decreasing it in ECs while increasing it in SMCs. These effects were reversed by propranolol, which by itself increased p-ERK1/2 in ECs. Isoprenaline β-AR mediated vasodilation of aortic rings was potentiated by the ERK1/2 inhi…
Differences in the signaling pathways of α(1A)- and α(1B)-adrenoceptors are related to different endosomal targeting.
2013
AIMS: To compare the constitutive and agonist-dependent endosomal trafficking of α(1A)- and α(1B)-adrenoceptors (ARs) and to establish if the internalization pattern determines the signaling pathways of each subtype. METHODS: Using CypHer5 technology and VSV-G epitope tagged α(1A)- and α(1B)-ARs stably and transiently expressed in HEK 293 cells, we analyzed by confocal microscopy the constitutive and agonist-induced internalization of each subtype, and the temporal relationship between agonist induced internalization and the increase in intracellular calcium (determined by FLUO-3 flouorescence), or the phosphorylation of ERK1/2 and p38 MAP kinases (determined by Western blot). RESULTS AND C…
Apremilast, a novel phosphodiesterase 4 (PDE4) inhibitor, regulates inflammation through multiple cAMP downstream effectors
2015
Introduction This work was undertaken to delineate intracellular signaling pathways for the PDE4 inhibitor apremilast and to examine interactions between apremilast, methotrexate and adenosine A2A receptors (A2AR). Methods After apremilast and LPS incubation, intracellular cAMP, TNF-α, IL-10, IL-6 and IL-1α were measured in the Raw264.7 monocytic murine cell line. PKA, Epac1/2 (signaling intermediates for cAMP) and A2AR knockdowns were performed by shRNA transfection and interactions with A2AR and A2BR, as well as with methotrexate were tested in vitro and in the murine air pouch model. Statistical differences were determined using one or two-way ANOVA or Student’s t test. The alpha nominal…
The three α1-adrenoceptor subtypes show different spatio-temporal mechanisms of internalization and ERK1/2 phosphorylation
2013
AbstractWe analyzed the kinetic and spatial patterns characterizing activation of the MAP kinases ERK 1 and 2 (ERK1/2) by the three α1-adrenoceptor (α1-AR) subtypes in HEK293 cells and the contribution of two different pathways to ERK1/2 phosphorylation: protein kinase C (PKC)-dependent ERK1/2 activation and internalization-dependent ERK1/2 activation. The different pathways of phenylephrine induced ERK phosphorylation were determined by western blot, using the PKC inhibitor Ro 31-8425, the receptor internalization inhibitor concanavalin A and the siRNA targeting β-arrestin 2. Receptor internalization properties were studied using CypHer5 technology and VSV-G epitope-tagged receptors. Activ…
a1D-Adrenoceptors are responsible for the high sensitivity and the slow time-course of noradrenaline-mediated contraction in conductance arteries.
2013
The objective of this study was to determine whether the different time-course characteristics of α1-adrenoceptor-mediated contraction in arteries can be related to the subtypes involved. Contractile responses to noradrenaline (NA) were compared with inositol phosphate accumulation and extracellular signal-regulated kinase (ERK)1/2 phosphorylation after α1-agonist stimuli in the same vessels in the presence or absence of α1-antagonists in rat or in α1-subtype knockout (KO) mice. Aorta, where α1D-AR is the main functional subtype, had higher sensitivity to NA (in respect of inositol phosphate [IP], pERK1/2, and contractile response) than tail artery, where the α1A-adrenoceptor subtype is pre…
Different β-adrenoceptor subtypes coupling to cAMP or NO/cGMP pathways: implications in the relaxant response of rat conductance and resistance vesse…
2013
Background and Purpose To analyse the relative contribution of β1-, β2- and β3-adrenoceptors (Adrb) to vasodilatation in conductance and resistance vessels, assessing the role of cAMP and/or NO/cGMP signalling pathways. Experimental Approach Rat mesenteric resistance artery (MRA) and aorta were used to analyse the Adrb expression by real-time-PCR and immunohistochemistry, and for the pharmacological characterization of Adrb-mediated activity by wire myography and tissue nucleotide accumulation. Key Results The mRNAs and protein for all Adrb were identified in endothelium and/or smooth muscle cells (SMCs) in both vessels. In MRA, Adrb1 signalled through cAMP, Adrb3 through both cAMP and cGMP…