Liste des publications

Les publications de l'équipe







IF du Neurocentre
IF1234567891011121314151617181920253035404550
Nombre00717310010600000001000100
%002542511400402200000004000400


28 publications

* equal contribution
Les IF indiqués ont été collectés par le Web of Sciences en Juin 2019



24/01/2019 | Neurobiol Dis   IF 5.2
Cannabinoid type-1 receptor blockade restores neurological phenotypes in two models for Down syndrome.
Navarro-Romero A, Vazquez-Oliver A, Gomis-Gonzalez M, Garzon-Montesinos C, Falcon-Moya R, Pastor A, Martin-Garcia E, Pizarro N, Busquets-Garcia A, Revest JM, Piazza PV, Bosch F, Dierssen M, de la Torre R, Rodriguez-Moreno A, Maldonado R, Ozaita A

Abstract:
Intellectual disability is the most limiting hallmark of Down syndrome, for which there is no gold-standard clinical treatment yet. The endocannabinoid system is a widespread neuromodulatory system involved in multiple functions including learning and memory processes. Alterations of this system contribute to the pathogenesis of several neurological and neurodevelopmental disorders. However, the involvement of the endocannabinoid system in the pathogenesis of Down syndrome has not been explored before. We used the best-characterized preclinical model of Down syndrome, the segmentally trisomic Ts65Dn model. In male Ts65Dn mice, cannabinoid type-1 receptor (CB1R) expression was enhanced and its function increased in hippocampal excitatory terminals. Knockdown of CB1R in the hippocampus of male Ts65Dn mice restored hippocampal-dependent memory. Concomitant with this result, pharmacological inhibition of CB1R restored memory deficits, hippocampal synaptic plasticity and adult neurogenesis in the subgranular zone of the dentate gyrus. Notably, the blockade of CB1R also normalized hippocampal-dependent memory in female Ts65Dn mice. To further investigate the mechanisms involved, we used a second transgenic mouse model overexpressing a single gene candidate for Down syndrome cognitive phenotypes, the dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A). CB1R pharmacological blockade similarly improved cognitive performance, synaptic plasticity and neurogenesis in transgenic male Dyrk1A mice. Our results identify CB1R as a novel druggable target potentially relevant for the improvement of cognitive deficits associated with Down syndrome.





23/09/2018 | Exp Neurol   IF 4.6
Serotonin2B receptors in the rat dorsal raphe nucleus exert a GABA-mediated tonic inhibitory control on serotonin neurons.
Cathala A, Devroye C, Drutel G, Revest JM, Artigas F, Spampinato U

Abstract:
The central serotonin2B receptor (5-HT2BR) is a well-established modulator of dopamine (DA) neuron activity in the rodent brain. Recent studies in rats have shown that the effect of 5-HT2BR antagonists on accumbal and medial prefrontal cortex (mPFC) DA outflow results from a primary action in the dorsal raphe nucleus (DRN), where they activate 5-HT neurons innervating the mPFC. Although the mechanisms underlying this interaction remain largely unknown, data in the literature suggest the involvement of DRN GABAergic interneurons in the control of 5-HT activity. The present study examined this hypothesis using in vivo (intracerebral microdialysis) and in vitro (immunohistochemistry coupled to reverse transcription-polymerase chain reaction) experimental approaches in rats. Intraperitoneal (0.16mg/kg) or intra-DRN (1muM) administration of the selective 5-HT2BR antagonist RS 127445 increased 5-HT outflow in both the DRN and the mPFC, these effects being prevented by the intra-DRN perfusion of the GABAA antagonist bicuculline (100muM), as well as by the subcutaneous (0.16mg/kg) or the intra-DRN (0.1muM) administration of the selective 5-HT1AR antagonist WAY 100635. The increase in DRN 5-HT outflow induced by the intra-DRN administration of the selective 5-HT reuptake inhibitor citalopram (0.1muM) was potentiated by the intra-DRN administration (0.5muM) of RS 127445 only in the absence of bicuculline perfusion. Finally, in vitro experiments revealed the presence of the 5-HT2BR mRNA on DRN GABAergic interneurons. Altogether, these results show that, in the rat DRN, 5-HT2BRs are located on GABAergic interneurons, and exert a tonic inhibitory control on 5-HT neurons innervating the mPFC.





05/03/2018 | Mol Psychiatry   IF 12
Depleting adult dentate gyrus neurogenesis increases cocaine-seeking behavior.
Deroche-Gamonet V, Revest JM, Fiancette JF, Balado E, Koehl M, Grosjean N, Abrous DN, Piazza PV

Abstract:
The hippocampus is the main locus for adult dentate gyrus (DG) neurogenesis. A number of studies have shown that aberrant DG neurogenesis correlates with many neuropsychiatric disorders, including drug addiction. Although clear causal relationships have been established between DG neurogenesis and memory dysfunction or mood-related disorders, evidence of the causal role of DG neurogenesis in drug-seeking behaviors has not been established. Here we assessed the role of new DG neurons in cocaine self-administration using an inducible transgenic approach that selectively depletes adult DG neurogenesis. Our results show that transgenic mice with decreased adult DG neurogenesis exhibit increased motivation to self-administer cocaine and a higher seeking response to cocaine-related cues. These results identify adult hippocampal neurogenesis as a key factor in vulnerability to cocaine addiction.





01/11/2014 | Neuropharmacology   IF 4.4
Serotonin receptor stimulation inhibits cocaine-induced Fos expression and DARPP-32 phosphorylation in the rat striatum independently of dopamine outflow.
Devroye C, Cathala A, Maitre M, Piazza PV, Abrous DN, Revest JM, Spampinato U

Abstract:
The serotonin2C receptor (5-HT2CR) is known to control dopamine (DA) neuron function by modulating DA neuronal firing and DA exocytosis at terminals. Recent studies assessing the influence of 5-HT2CRs on cocaine-induced neurochemical and behavioral responses have shown that 5-HT2CRs can also modulate mesoaccumbens DA pathway activity at post-synaptic level, by controlling DA transmission in the nucleus accumbens (NAc), independently of DA release itself. A similar mechanism has been proposed to occur at the level of the nigrostriatal DA system. Here, using in vivo microdialysis in freely moving rats and molecular approaches, we assessed this hypothesis by studying the influence of the 5-HT2CR agonist Ro 60-0175 on cocaine-induced responses in the striatum. The intraperitoneal (i.p.) administration of 1 mg/kg Ro 60-0175 had no effect on the increase in striatal DA outflow induced by cocaine (15 mg/kg, i.p.). Conversely, Ro 60-0175 inhibited cocaine-induced Fos immunoreactivity and phosphorylation of the DA and c-AMP regulated phosphoprotein of Mr 32 kDa (DARPP-32) at threonine 75 residue in the striatum. Finally, the suppressant effect of Ro 60-0175 on cocaine-induced DARPP-32 phosphorylation was reversed by the selective 5-HT2CR antagonist SB 242084 (0.5 mg/kg, i.p.). In keeping with the key role of DARPP-32 in DA neurotransmission, our results demonstrate that 5-HT2CRs are capable of modulating nigrostriatal DA pathway activity at post-synaptic level, by specifically controlling DA signaling in the striatum.





Abstract:
In keeping with its ability to control the mesoaccumbens dopamine (DA) pathway, the serotonin2C receptor (5-HT2C R) plays a key role in mediating the behavioral and neurochemical effects of drugs of abuse. Studies assessing the influence of 5-HT2C R agonists on cocaine-induced responses have suggested that 5-HT2C Rs can modulate mesoaccumbens DA pathway activity independently of accumbal DA release, thereby controlling DA transmission in the nucleus accumbens (NAc). In the present study, we assessed this hypothesis by studying the influence of the 5-HT2C R agonist Ro 60-0175 on cocaine-induced behavioral, neurochemical and molecular responses. The i.p. administration of 1 mg/kg Ro 60-0175 inhibited hyperlocomotion induced by cocaine (15 mg/kg, i.p.), had no effect on cocaine-induced DA outflow in the shell, and increased it in the core subregion of the NAc. Furthermore, Ro 60-0175 inhibited the late-onset locomotion induced by the subcutaneous administration of the DA-D2 R agonist quinpirole (0.5 mg/kg), as well as cocaine-induced increase in c-Fos immunoreactivity in NAc subregions. Finally, Ro 60-0175 inhibited cocaine-induced phosphorylation of the DA and c-AMP regulated phosphoprotein of Mr 32 kDa (DARPP-32) at threonine residues in the NAc core, this effect being reversed by the selective 5-HT2C R antagonist SB 242084 (0.5 mg/kg, i.p.). Altogether, these findings demonstrate that 5-HT2C Rs are capable of modulating mesoaccumbens DA pathway activity at post-synaptic level by specifically controlling DA signaling in the NAc core subregion. In keeping with the tight relationship between locomotor activity and NAc DA function, this interaction could participate in the inhibitory control of cocaine-induced locomotor activity.





03/01/2014 | Science   IF 41
Pregnenolone can protect the brain from cannabis intoxication.
Vallee M, Vitiello S, Bellocchio L, Hebert-Chatelain E, Monlezun S, Martin-Garcia E, Kasanetz F, Baillie GL, Panin F, Cathala A, Roullot-Lacarriere V, Fabre S, Hurst DP, Lynch DL, Shore DM, Deroche-Gamonet V, Spampinato U, Revest JM, Maldonado R, Reggio PH, Ross RA, Marsicano G, Piazza PV

Abstract:
Pregnenolone is considered the inactive precursor of all steroid hormones, and its potential functional effects have been largely uninvestigated. The administration of the main active principle of Cannabis sativa (marijuana), Delta(9)-tetrahydrocannabinol (THC), substantially increases the synthesis of pregnenolone in the brain via activation of the type-1 cannabinoid (CB1) receptor. Pregnenolone then, acting as a signaling-specific inhibitor of the CB1 receptor, reduces several effects of THC. This negative feedback mediated by pregnenolone reveals a previously unknown paracrine/autocrine loop protecting the brain from CB1 receptor overactivation that could open an unforeseen approach for the treatment of cannabis intoxication and addiction.

Get Full Text on Science



15/10/2013 | Mol Psychiatry   IF 12
BDNF-TrkB signaling through Erk1/2 phosphorylation mediates the enhancement of fear memory induced by glucocorticoids.
Revest JM, Le Roux A, Roullot-Lacarriere V, Kaouane N, Vallee M, Kasanetz F, Rouge-Pont F, Tronche F, Desmedt A, Piazza PV

Abstract:
Activation of glucocorticoid receptors (GR) by glucocorticoid hormones (GC) enhances contextual fear memories through the activation of the Erk1/2MAPK signaling pathway. However, the molecular mechanism mediating this effect of GC remains unknown. Here we used complementary molecular and behavioral approaches in mice and rats and in genetically modified mice in which the GR was conditionally deleted (GRNesCre). We identified the tPA-BDNF-TrkB signaling pathway as the upstream molecular effectors of GR-mediated phosphorylation of Erk1/2MAPK responsible for the enhancement of contextual fear memory. These findings complete our knowledge of the molecular cascade through which GC enhance contextual fear memory and highlight the role of tPA-BDNF-TrkB-Erk1/2MAPK signaling pathways as one of the core effectors of stress-related effects of GC.Molecular Psychiatry advance online publication, 15 October 2013; doi:10.1038/mp.2013.134.





15/05/2012 | Mol Psychiatry   IF 12
Prefrontal synaptic markers of cocaine addiction-like behavior in rats.
Kasanetz F*, Lafourcade M*, Deroche-Gamonet V*, Revest JM, Berson N, Balado E, Fiancette JF, Renault P, Piazza PV*, Manzoni OJ*

Abstract:
Defining the drug-induced neuroadaptations specifically associated with the behavioral manifestation of addiction is a daunting task. To address this issue, we used a behavioral model that differentiates rats controlling their drug use (Non-Addict-like) from rats undergoing transition to addiction (Addict-like). Dysfunctions in prefrontal cortex (PFC) synaptic circuits are thought to be responsible for the loss of control over drug taking that characterizes addicted individuals. Here, we studied the synaptic alterations in prelimbic PFC (pPFC) circuits associated with transition to addiction. We discovered that some of the changes induced by cocaine self-administration (SA), such as the impairment of the endocannabinoid-mediated long-term synaptic depression (eCB-LTD) was similarly abolished in Non-Addict- and Addict-like rats and thus unrelated to transition to addiction. In contrast, metabotropic glutamate receptor 2/3-mediated LTD (mGluR2/3-LTD) was specifically suppressed in Addict-like rats, which also show a concomitant postsynaptic plasticity expressed as a change in the relative contribution of AMPAR and NMDAR to basal glutamate-mediated synaptic transmission. Addiction-associated synaptic alterations in the pPFC were not fully developed at early stages of cocaine SA, when addiction-like behaviors are still absent, suggesting that pathological behaviors appear once the pPFC is compromised. These data identify specific synaptic impairments in the pPFC associated with addiction and support the idea that alterations of synaptic plasticity are core markers of drug dependence.Molecular Psychiatry advance online publication, 15 May 2012; doi:10.1038/mp.2012.59.





02/2012 | Hippocampus   IF 3.3
Adult-born neurons are necessary for extended contextual discrimination.
Tronel S, Belnoue L, Grosjean N, Revest JM, Piazza PV, Koehl M, Abrous DN

Abstract:
New neurons are continuously produced in the adult dentate gyrus of the hippocampus. It has been shown that one of the functions of adult neurogenesis is to support spatial pattern separation, a process that transforms similar memories into nonoverlapping representations. This prompted us to investigate whether adult-born neurons are required for discriminating two contexts, i.e., for identifying a familiar environment and detect any changes introduced in it. We show that depleting adult-born neurons impairs the animal's ability to disambiguate two contexts after extensive training. These data suggest that the continuous production of new dentate neurons plays a crucial role in extracting and separating efficiently contextual representation in order to discriminate features within events.





15/06/2011 | J Neurosci Methods   IF 2.8
Western blot detection of brain phosphoproteins after performing Laser
Microdissection and Pressure Catapulting (LMPC).

Maitre M, Roullot-Lacarriere V , Piazza PV , Revest JM

Abstract:
The Central Nervous System (CNS) is constituted of complex and specific anatomical regions that cluster together and interact with each other with the ultimate objective of receiving and delivering information. This information is characterized by selective biochemical changes that happen within specific brain sub-regions. Most of these changes involve a dynamic balance between kinase and phosphatase activities. The fine-tuning of this kinase/phosphatase balance is thus critical for neuronal adaptation, transition to long-term responses and higher brain functions including specific behaviors. Data emerging from several biological systems may suggest that disruption of this dynamic cell signaling balance within specific brain sub-regions leads to behavioral impairments. Therefore, accurate and powerful techniques are required to study global changes in protein expression levels and protein activities in specific groups of cells. Laser-based systems for tissue microdissection represent a method of choice enabling more accurate proteomic profiling. The goal of this study was to develop a methodological approach using Laser Microdissection and Pressure Catapulting (LMPC) technology combined with an immunoblotting technique in order to specifically detect the expression of phosphoproteins in particular small brain areas.