Dr. Topolnik is researcher at the Centre de recherche du CHU de Québec and professor at the Department of Biochemistry, Microbiology and Bio-informatics of Laval University’s Faculty of Science and Engineering. She began her academic career at Laval University in 2007 as an assistant professor, affiliated with the Robert-Giffard Research Center. She was recruited within the framework of the strategic project in biophotonics and the creation of the Center of neurophotonics. By combining her talents in research with her advanced expertise in optophysiological and optogenetic technologies, Dr. Topolnik was one of the first researchers to fill a niche in neurophotonics at Laval University. She played a major role in the development of multidisciplinary research at Laval University, as a professor of the international school Frontiers in Neurophotonics. Dr. Topolnik is a recipient of the University Faculty Award for Women in Science and Engineering from the Natural Science and Engineering Council of Canada (NSERC) and a “Professor-Star Award” from Laval University’s Faculty of Science and Engineering.
Dr. Topolnik’s research program focusses on the cellular and synaptic mechanisms involved in the coordination and processing of information by the cortical circuits. Her team explores how sensory information is integrated and modified by the GABAergic inhibitory interneurons, and how these processes are altered in neurological and neurodegenerative disorders, in particular epilepsy, Alzheimer’s disease, and amyotrophic lateral sclerosis.
Synaptic signaling and plasticity
The team explores the molecular and cellular mechanisms of memory formation, using recordings of electrical and biochemical activity at synapses. The two-photon microscopy, in combination with patch-clamp recordings and optogenetics, are used to study neuron synaptic activity and flow of calcium ions through pre- and post-synaptic channels.
Cellular composition and functioning of cortical circuits
The project focusses on the cortical regions responsible for memory formation, and contextual learning. The goal is to understand the cellular diversity and functional specialization of GABAergic interneurons, making up cortical circuits to understand their role in mnemonic processes.
The circuit dysfunction in neurodegenerative diseases
In neurodegenerative diseases, such as Alzheimer’s disease and amyotrophic lateral sclerosis, the intrinsic and synaptic properties of certain types of neurons are altered early in the progress of the disease. This leads to circuit activity imbalance and the beginning of first functional deficits. To understand the mechanisms of these changes, the team applies advanced optical techniques to genetic mouse models to monitor the abnormal brain activity with cellular resolution. The pharmacological, pharmacogenetics and immunological interventions are directed towards the restoration of synaptic, cellular and circuit function.
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Connectivity and network state-dependent recruitment of long-range VIP-GABAergic neurons in the mouse hippocampus.Journal Article
Nat Commun, 9 (1), pp. 5043, 2018, ISSN: 2041-1723.
Two-photon Calcium Imaging in Neuronal Dendrites in Brain Slices.Journal Article
J Vis Exp, (133), 2018.
Mechanisms of Supralinear Calcium Integration in Dendrites of Hippocampal CA1 Fast-Spiking Cells.Journal Article
Front Synaptic Neurosci, 10 , pp. 47, 2018, ISSN: 1663-3563.
Simple platform for chronic imaging of hippocampal activity during spontaneous behaviour in an awake mouse.Journal Article
Sci Rep, 7 , pp. 43388, 2017, ISSN: 2045-2322.
Target-specific alterations in the VIP inhibitory drive to hippocampal GABAergic cells after status epilepticus.Journal Article
Exp Neurol, 292 , pp. 102-112, 2017, ISSN: 0014-4886.
Using a Semi-Automated Strategy to Develop Multi-Compartment Models That Predict Biophysical Properties of Interneuron-Specific 3 (IS3) Cells in Hippocampus.Journal Article
eNeuro, 3 (4), 2016, ISSN: 2373-2822.
Coordination of dendritic inhibition through local disinhibitory circuits.Journal Article
Front Synaptic Neurosci, 7 , pp. 5, 2015, ISSN: 1663-3563.
Dendritic inhibition provided by interneuron-specific cells controls the firing rate and timing of the hippocampal feedback inhibitory circuitry.Journal Article
J Neurosci, 34 (13), pp. 4534-47, 2014, ISSN: 0270-6474.
Dendritic calcium nonlinearities switch the direction of synaptic plasticity in fast-spiking interneurons.Journal Article
J Neurosci, 34 (11), pp. 3864-77, 2014, ISSN: 0270-6474.
Functional compartmentalisation and regulation of postsynaptic Ca2+ transients in inhibitory interneurons.Journal Article
Cell Calcium, 52 (5), pp. 339-46, 2012, ISSN: 0143-4160.
- Centre de recherche du CHU de Québec - Université Laval, Subvention, Centre hospitalier universitaire de Québec - Université Laval, Centres de recherche affiliés, from 2017-01-01 to 2099-12-31
- Centre thématique de recherche en neurosciences, Subvention, Institutionnel - BDR, BDR - Centres de recherche reconnus, from 1999-06-01 to 2023-05-01
- Dendritic inhibition in hippocampal circuits, Subvention, Conseil de recherches en sciences naturelles et génie Canada, Subventions à la découverte SD (individuelles et d'équipe), from 2020-04-01 to 2025-03-31
- Inhibitory control of hippocampal inhibitory circuits: cell types, neuromodulation and function, Subvention, Instituts de recherche en santé du Canada, Subvention Projet, from 2019-10-01 to 2024-09-30
- Investigating the contribution of Shank3 in Alzheimer's disease, Subvention, Instituts de recherche en santé du Canada, Subvention Projet, from 2018-04-01 to 2023-03-31
- Mechanisms of dendritic integration and plasticity in GABAergic inhibitory interneurons, Subvention, Instituts de recherche en santé du Canada, Subvention de fonctionnement, from 2015-07-01 to 2021-06-30
Recently finished projects
- Inhibitory control of hippocampal inhibitory circuits: cellular mechanisms and function, Subvention, Instituts de recherche en santé du Canada, Subvention de fonctionnement, from 2014-07-01 to 2019-06-30
- Targeting microglia-synapse interactions to rescue brain circuits elimination and cognitive dysfunction, Subvention, Instituts de recherche en santé du Canada, Subventions Fondation, from 2016-07-01 to 2020-03-31