Papers by christine belloir
HAL (Le Centre pour la Communication Scientifique Directe), Jul 4, 2012
National audienc
PLOS ONE, Apr 2, 2014
The human olfactory system recognizes a broad spectrum of odorants using approximately 400 differ... more The human olfactory system recognizes a broad spectrum of odorants using approximately 400 different olfactory receptors (hORs). Although significant improvements of heterologous expression systems used to study interactions between ORs and odorant molecules have been made, screening the olfactory repertoire of hORs remains a tremendous challenge. We therefore developed a chemical systems level approach based on protein-protein association network to investigate novel hOR-odorant relationships. Using this new approach, we proposed and validated new bioactivities for odorant molecules and OR2W1, OR51E1 and OR5P3. As it remains largely unknown how human perception of odorants influence or prevent diseases, we also developed an odorant-protein matrix to explore global relationships between chemicals, biological targets and disease susceptibilities. We successfully experimentally demonstrated interactions between odorants and the cannabinoid receptor 1 (CB1) and the peroxisome proliferator-activated receptor gamma (PPARc). Overall, these results illustrate the potential of integrative systems chemical biology to explore the impact of odorant molecules on human health, i.e. human odorome.
Mutation Research, Mar 1, 2000
HAL (Le Centre pour la Communication Scientifique Directe), Oct 10, 2013
Développement d’une méthode d’analyse de la désorption de composés d’arôme par PTR-MS sur un modè... more Développement d’une méthode d’analyse de la désorption de composés d’arôme par PTR-MS sur un modèle in vitro de muqueuse orale. Congrès français de Spectrométrie de Masse et d'Analyse Protéomique (SMAP 2015
HAL (Le Centre pour la Communication Scientifique Directe), Jan 16, 2014
HAL (Le Centre pour la Communication Scientifique Directe), Sep 1, 2022
HAL (Le Centre pour la Communication Scientifique Directe), 2018
HAL (Le Centre pour la Communication Scientifique Directe), Sep 11, 2019
International audienc
Zenodo (CERN European Organization for Nuclear Research), Oct 29, 2021
Vitamins play an important role in maintaining normal physiologic and metabolic functions. Vitami... more Vitamins play an important role in maintaining normal physiologic and metabolic functions. Vitamins are known to generate bitterness, which may contribute to the off-taste of nutritional supplements. This negative sensation may decrease product acceptability and patient compliance. Few studies have examined taste thresholds and sensory sensing mechanisms at the origin of vitamin taste detection. To better understand vitamin bitterness perception, we combined human sensory analysis and taste receptor functional assays. We measured the aqueous taste detection threshold of four B vitamins using sensory difference tests. Challenging the 25 human bitter taste 2 receptors (TAS2Rs), we found that three vitamins stimulated one or more receptors. For each positive molecule-TAS2R combination, we measured the half-maximum effective concentrations (EC50). Thus, we found that the combination of sensory and biological data can provide useful explanations for the bitter detection of vitamins.
HAL (Le Centre pour la Communication Scientifique Directe), Apr 14, 2019
HAL (Le Centre pour la Communication Scientifique Directe), Sep 7, 2011
International audienc
The transduction of odorant binding into cellular signaling by olfactory receptors (ORs) is not u... more The transduction of odorant binding into cellular signaling by olfactory receptors (ORs) is not understood and knowing its mechanism would enable developing new pharmacology and biohybrid electronic detectors of volatile organic compounds bearing high sensitivity and selectivity. The electrical characterization of ORs in bulk experiments is subject to microscopic models and assumptions. We have directly determined the nanoscale electrical properties of ORs immobilized in a fixed orientation, and their change upon odorant binding, using electrochemical scanning tunneling microscopy (EC-STM) in near-physiological conditions. Recordings of current versus time, distance, and electrochemical potential allows determining the OR impedance parameters and their dependence with odorant binding. Our results allow validating OR structural-electrostatic models and their functional activation processes.
HAL (Le Centre pour la Communication Scientifique Directe), Sep 2, 2017
PURPOSE. Successful regeneration and re-establishment of synaptic connections in the adult centra... more PURPOSE. Successful regeneration and re-establishment of synaptic connections in the adult central nervous system is a complex process determined by both the exterior environment and the endogenous neural activity of the regenerating growth cones. The purpose of this study was to determine the expression and properties of voltage-gated sodium channels (Na v) expressed by regenerating growth cones. METHODS. Na v channels were studied in an organotypic explant culture of the adult rat retina by immunocytochemistry and whole-cell, patch-clamp recordings. RESULTS. Regenerating axons and growth cones, but not glial processes, expressed Na v channels. Whole-cell, current-clamp recordings from growth cones displayed a high input resistance of 1.29 G⍀ and a resting membrane potential of Ϫ69.0 mV. All growth cones responded to depolarizing voltage steps with fast, transient, inward currents mediated by Na ϩ ions, followed by slow, sustained outward K ϩ currents. Half-maximum activation clustered in two groups, suggesting the presence of at least two Na v channel isoforms. Steady state inactivation and recovery from fast inactivation were characterized by a half-maximum value of Ϫ69.7 mV and by a time constant of 3.64 ms, respectively. Injection of depolarizing current steps larger than threshold (Ϫ29.3 mV) consistently induced a single action potential, whereas ganglion cell bodies responded to above-threshold stimulation with a series of fast, all-or-none action potentials. CONCLUSIONS. These experiments describe for the first time the biophysical properties of Na v channels recorded from the growth cones of regenerating retinal ganglion cells and contrast their properties with those of adult retinal ganglion cells.
HAL (Le Centre pour la Communication Scientifique Directe), Jun 3, 2019
International audienc
HAL (Le Centre pour la Communication Scientifique Directe), Jul 3, 2016
Interactions between aroma compounds and the oral mucosa could be responsible for aroma persisten... more Interactions between aroma compounds and the oral mucosa could be responsible for aroma persistence. 4. international conference on food oral processing - “Food Oral Processing through life: interplay between food structure, sensory, pleasure and nutritional needs.”
HAL (Le Centre pour la Communication Scientifique Directe), Sep 10, 2014
Molecules, Apr 7, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Scientific Reports, Jun 8, 2022
mediate key deleterious effects of pro-inflammatory cytokines in IBD 22,23 , we further investiga... more mediate key deleterious effects of pro-inflammatory cytokines in IBD 22,23 , we further investigated it in presence of 3-oxo-C12:2-HSL. 3-oxo-C12:2 prevents the activation of the JAK-STAT pathway. To explore the effects of 3-oxo-C12:2-HSL on the JAK-STAT pathway, we analysed the phosphorylation level of proteins involved in this pathway. As the latter is composed of a family of JAK and STAT proteins, we studied several of them in RAW264.7 macrophages activated by LPS and IFNγ and exposed or not to 3-oxo-C12:2-HSL (Fig. 3). When cells were treated with the pro-inflammatory cocktail, we observed an increase of the phosphorylation of JAK1, JAK2, STAT1, STAT3 proteins (Fig. 3a-e). When activated macrophages were exposed to 3-oxo-C12:2-HSL, a reduced phosphorylation level of JAK1 (− 50%) and STAT1 (− 40%) protein was observed, in comparison with activated cells without AHL treatment (Fig. 3a,b). However, JAK2 and STAT3 phosphorylation levels were not significantly altered upon exposure to 3-oxo-C12:2-HSL. These results demonstrate that 3-oxo-C12:2-HSL prevents the activation of the JAK-STAT pathway, by specifically reducing the phosphorylation of JAK1 and STAT1 proteins.
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Papers by christine belloir