Neurocentre Magendie

Andreas FRICK




Chercheur

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Cursus:
« Dr. rer nat » (PhD): summa cum laude. Institut Max-Planck pour Psychiatrie, Université Technique de Munich, Munich, Allemagne. Superviseur Pr. H. U. Dodt et Pr. H. Zieglgaensberger
Chercheur postdoctorant, boursier d'excellence Feodor Lynen (Alexander von Humboldt foundation). Baylor College of Medicine, Division de Neuroscience, Houston, Texas, Etats-Unis. Superviseur : Pr Daniel Johnston
Chargé de Recherche. Institut Max-Planck pour la Recherche Médicale, Département de Biologie Cellulaire, Heidelberg, Allemagne. Directeur : Pr. Bert Sakmann
Chargé de recherche INSERM «AVENIR », Neurocentre Magendie (2008-2010)
Chercheur INSERM statutaire CR1, Neurocentre Magendie (depuis 2009)






28 publication(s) depuis Novembre 1998:


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Les IF indiqués ont été collectés par le Web of Sciences en


07/06/2017 | autism res
Behavioral abnormalities in the Fmr1-KO2 mouse model of fragile X syndrome: The relevance of early life phases.
Gaudissard J*, Ginger M*, Premoli M, Memo M, Frick A*, Pietropaolo S*

Abstract:
Fragile X syndrome (FXS) is a developmental disorder caused by a mutation in the X-linked FMR1 gene, coding for the FMRP protein which is largely involved in synaptic function. FXS patients present several behavioral abnormalities, including hyperactivity, anxiety, sensory hyper-responsiveness, and cognitive deficits. Autistic symptoms, e.g., altered social interaction and communication, are also often observed: FXS is indeed the most common monogenic cause of autism. Mouse models of FXS are therefore of great interest for research on both FXS and autistic pathologies. The Fmr1-KO2 mouse line is the most recent FXS model, widely used for brain studies; surprisingly, little is known about the face validity of this model, i.e., its FXS-like behavioral phenotype. Furthermore, no data are available for the age-related expression of the pathological phenotypes in this mouse line, a critical issue for modelling neurodevelopmental disorders. Here we performed an extensive behavioral characterization of the KO2 model at infancy, adolescent and adult ages. Hyperactivity, altered emotionality, sensory hyper-responsiveness and memory deficits were already present in KO mice at adolescence and remained evident at adulthood. Alterations in social behaviors were instead observed only in young KO animals: during the first 2 weeks of life, KOs emitted longer ultrasonic vocalizations compared to their WT littermates and as adolescents they displayed more aggressive behaviors towards a conspecific. These results strongly support the face validity of the KO2 mouse as a model for FXS, at the same time demonstrating that its ability to recapitulate social autistic-relevant phenotypes depends on early testing ages. Autism Res 2017. (c) 2017 International Society for Autism Research, Wiley Periodicals, Inc.




10/04/2017 | Nat Neurosci   IF 17.8
Abnormal wiring of CCK+ basket cells disrupts spatial information coding.
Del Pino I, Brotons-Mas JR, Marques-Smith A, Marighetto A, Frick A, Marin O, Rico B

Abstract:
The function of cortical GABAergic interneurons is largely determined by their integration into specific neural circuits, but the mechanisms controlling the wiring of these cells remain largely unknown. This is particularly true for a major population of basket cells that express the neuropeptide cholecystokinin (CCK). Here we found that the tyrosine kinase receptor ErbB4 was required for the normal integration into cortical circuits of basket cells expressing CCK and vesicular glutamate transporter 3 (VGlut3). The number of inhibitory synapses made by CCK+VGlut3+ basket cells and the inhibitory drive they exerted on pyramidal cells were reduced in conditional mice lacking ErbB4. Developmental disruption of the connectivity of these cells diminished the power of theta oscillations during exploratory behavior, disrupted spatial coding by place cells, and caused selective alterations in spatial learning and memory in adult mice. These results suggest that normal integration of CCK+ basket cells in cortical networks is key to support spatial coding in the hippocampus.




2017 | Methods Mol Biol
Dual Anterograde and Retrograde Viral Tracing of Reciprocal Connectivity.
Haberl MG, Ginger M, Frick A

Abstract:
Current large-scale approaches in neuroscience aim to unravel the complete connectivity map of specific neuronal circuits, or even the entire brain. This emerging research discipline has been termed connectomics. Recombinant glycoprotein-deleted rabies virus (RABV G) has become an important tool for the investigation of neuronal connectivity in the brains of a variety of species. Neuronal infection with even a single RABV G particle results in high-level transgene expression, revealing the fine-detailed morphology of all neuronal features-including dendritic spines, axonal processes, and boutons-on a brain-wide scale. This labeling is eminently suitable for subsequent post-hoc morphological analysis, such as semiautomated reconstruction in 3D. Here we describe the use of a recently developed anterograde RABV G variant together with a retrograde RABV G for the investigation of projections both to, and from, a particular brain region. In addition to the automated reconstruction of a dendritic tree, we also give as an example the volume measurements of axonal boutons following RABV G-mediated fluorescent marker expression. In conclusion RABV G variants expressing a combination of markers and/or tools for stimulating/monitoring neuronal activity, used together with genetic or behavioral animal models, promise important insights in the structure-function relationship of neural circuits.




17/06/2016 | Nat Commun   IF 12.1
Early synaptic deficits in the APP/PS1 mouse model of Alzheimer's disease involve neuronal adenosine A2A receptors.
Viana da Silva S, Haberl MG, Zhang P, Bethge P, Lemos C, Goncalves N, Gorlewicz A, Malezieux M, Goncalves FQ, Grosjean N, Blanchet C, Frick A, Nagerl UV, Cunha RA, Mulle C

Abstract:
Synaptic plasticity in the autoassociative network of recurrent connections among hippocampal CA3 pyramidal cells is thought to enable the storage of episodic memory. Impaired episodic memory is an early manifestation of cognitive deficits in Alzheimer's disease (AD). In the APP/PS1 mouse model of AD amyloidosis, we show that associative long-term synaptic potentiation (LTP) is abolished in CA3 pyramidal cells at an early stage. This is caused by activation of upregulated neuronal adenosine A2A receptors (A2AR) rather than by dysregulation of NMDAR signalling or altered dendritic spine morphology. Neutralization of A2AR by acute pharmacological inhibition, or downregulation driven by shRNA interference in a single postsynaptic neuron restore associative CA3 LTP. Accordingly, treatment with A2AR antagonists reverts one-trial memory deficits. These results provide mechanistic support to encourage testing the therapeutic efficacy of A2AR antagonists in early AD patients.




11/2015 | sci adv
Structural-functional connectivity deficits of neocortical circuits in the Fmr1 (-/y) mouse model of autism.
Haberl MG, Zerbi V, Veltien A, Ginger M, Heerschap A, Frick A

Abstract:
Fragile X syndrome (FXS), the most common inherited form of intellectual disability disorder and a frequent cause of autism spectrum disorder (ASD), is characterized by a high prevalence of sensory symptoms. Perturbations in the anatomical connectivity of neocortical circuits resulting in their functional defects have been hypothesized to contribute to the underlying etiology of these disorders. We tested this idea by probing alterations in the functional and structural connectivity of both local and long-ranging neocortical circuits in the Fmr1 (-/y) mouse model of FXS. To achieve this, we combined in vivo ultrahigh-field diffusion tensor magnetic resonance imaging (MRI), functional MRI, and viral tracing approaches in adult mice. Our results show an anatomical hyperconnectivity phenotype for the primary visual cortex (V1), but a disproportional low connectivity of V1 with other neocortical regions. These structural data are supported by defects in the structural integrity of the subcortical white matter in the anterior and posterior forebrain. These anatomical alterations might contribute to the observed functional decoupling across neocortical regions. We therefore identify FXS as a 'connectopathy,' providing a translational model for understanding sensory processing defects and functional decoupling of neocortical areas in FXS and ASD.




10/11/2014 | Nat Neurosci   IF 17.8
Dendritic channelopathies contribute to neocortical and sensory hyperexcitability in Fmr1 mice.
Zhang Y*, Bonnan A*, Bony G*, Ferezou I, Pietropaolo S, Ginger M, Sans N, Rossier J, Oostra B, Lemasson G, Frick A

Abstract:
Hypersensitivity in response to sensory stimuli and neocortical hyperexcitability are prominent features of Fragile X Syndrome (FXS) and autism spectrum disorders, but little is known about the dendritic mechanisms underlying these phenomena. We found that the primary somatosensory neocortex (S1) was hyperexcited in response to tactile sensory stimulation in Fmr1-/y mice. This correlated with neuronal and dendritic hyperexcitability of S1 pyramidal neurons, which affect all major aspects of neuronal computation, from the integration of synaptic input to the generation of action potential output. Using dendritic electrophysiological recordings, calcium imaging, pharmacology, biochemistry and a computer model, we found that this defect was, at least in part, attributable to the reduction and dysfunction of dendritic h- and BKCa channels. We pharmacologically rescued several core hyperexcitability phenomena by targeting BKCa channels. Our results provide strong evidence pointing to the utility of BKCa channel openers for the treatment of the sensory hypersensitivity aspects of FXS.




Abstract:
Dendritic spines are basic units of neuronal information processing and their structure is closely reflected in their function. Defects in synaptic development are common in neurodevelopmental disorders, making detailed knowledge of age-dependent changes in spine morphology essential for understanding disease mechanisms. However, little is known about the functionally important fine-morphological structures, such as spine necks, due to the limited spatial resolution of conventional light microscopy. Using stimulated emission depletion microscopy (STED), we examined spine morphology at the nanoscale during normal development in mice, and tested the hypothesis that it is impaired in a mouse model of fragile X syndrome (FXS). In contrast to common belief, we find that, in normal development, spine heads become smaller, while their necks become wider and shorter, indicating that synapse compartmentalization decreases substantially with age. In the mouse model of FXS, this developmental trajectory is largely intact, with only subtle differences that are dependent on age and brain region. Together, our findings challenge current dogmas of both normal spine development as well as spine dysgenesis in FXS, highlighting the importance of super-resolution imaging approaches for elucidating structure-function relationships of dendritic spines.




11/04/2014 | Brain Struct Funct   IF 4.7
An anterograde rabies virus vector for high-resolution large-scale reconstruction of 3D neuron morphology.
Haberl MG*, Viana da Silva S*, Guest JM, Ginger M, Ghanem A, Mulle C, Oberlaender M, Conzelmann KK, Frick A

Abstract:
Glycoprotein-deleted rabies virus (RABV G) is a powerful tool for the analysis of neural circuits. Here, we demonstrate the utility of an anterograde RABV G variant for novel neuroanatomical approaches involving either bulk or sparse neuronal populations. This technology exploits the unique features of RABV G vectors, namely autonomous, rapid high-level expression of transgenes, and limited cytotoxicity. Our vector permits the unambiguous long-range and fine-scale tracing of the entire axonal arbor of individual neurons throughout the brain. Notably, this level of labeling can be achieved following infection with a single viral particle. The vector is effective over a range of ages (>14 months) aiding the studies of neurodegenerative disorders or aging, and infects numerous cell types in all brain regions tested. Lastly, it can also be readily combined with retrograde RABV G variants. Together with other modern technologies, this tool provides new possibilities for the investigation of the anatomy and physiology of neural circuits.




Abstract:
Dendritic spines are basic units of neuronal information processing and their structure is closely reflected in their function. Defects in synaptic development are common in neurodevelopmental disorders, making detailed knowledge of age-dependent changes in spine morphology essential for understanding disease mechanisms. However, little is known about the functionally important fine- morphological structures, such as spine necks, due to the limited spatial resolution of conventional light microscopy. Using stimulated emission depletion microscopy (STED), we examined spine morphology at the nanoscale during normal development in mice, and tested the hypothesis that it is impaired in a mouse model of fragile X syndrome (FXS). In contrast to common belief, we find that, in normal development, spine heads become smaller, while their necks become wider and shorter, indicating that synapse compartmentalization decreases substantially with age. In the mouse model of FXS, this developmental trajectory is largely intact, with only subtle differences that are dependent on age and brain region. Together, our findings challenge current dogmas of both normal spine development as well as spine dysgenesis in FXS, highlighting the importance of super-resolution imaging approaches for elucidating structure–function relationships of dendritic spines.




2013 | Front Neural Circuits   IF 5.1
Revealing the secrets of neuronal circuits with recombinant rabies virus technology.
Ginger M*, Haberl M*, Conzelmann KK, Schwarz MK, Frick A

Abstract:
An understanding of how the brain processes information requires knowledge of the architecture of its underlying neuronal circuits, as well as insights into the relationship between architecture and physiological function. A range of sophisticated tools is needed to acquire this knowledge, and recombinant rabies virus (RABV) is becoming an increasingly important part of this essential toolbox. RABV has been recognized for years for its properties as a synapse-specific trans-neuronal tracer. A novel genetically modified variant now enables the investigation of specific monosynaptic connections. This technology, in combination with other genetic, physiological, optical, and computational tools, has enormous potential for the visualization of neuronal circuits, and for monitoring and manipulating their activity. Here we will summarize the latest developments in this fast moving field and provide a perspective for the use of this technology for the dissection of neuronal circuit structure and function in the normal and diseased brain.