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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Cortical disinhibitory circuits: cell types, connectivity and function.Journal Article
Trends Neurosci, 44 (8), 2021, ISSN: 0166-2236.
Cholinergic Modulation of Dendritic Signaling in Hippocampal GABAergic Inhibitory Interneurons.Journal Article
Sex Differences of Microglia and Synapses in the Hippocampal Dentate Gyrus of Adult Mouse Offspring Exposed to Maternal Immune Activation.Journal Article
Front Cell Neurosci, 14 , 2020.
Alterations in Intrinsic and Synaptic Properties of Hippocampal CA1 VIP Interneurons During Aging.Journal Article
Front Cell Neurosci, 14 , 2020.
Common Principles in Functional Organization of VIP/Calretinin Cell-Driven Disinhibitory Circuits Across Cortical Areas.Journal Article
Front Neural Circuits, 14 , 2020.
Corrigendum: Synaptic Mechanisms Underlying the Network State-Dependent Recruitment of VIP-Expressing Interneurons in the CA1 Hippocampus.Journal Article
Cereb Cortex, 30 (5), 2020.
Synaptic Mechanisms Underlying the Network State-Dependent Recruitment of VIP-Expressing Interneurons in the CA1 Hippocampus.Journal Article
Cereb Cortex, 30 (6), 2020.
Calcium Dynamics in Dendrites of Hippocampal CA1 Interneurons in Awake Mice.Journal Article
Front Cell Neurosci, 13 , 2019.
Transcriptomic profile of the subiculum-projecting VIP GABAergic neurons in the mouse CA1 hippocampus.Journal Article
Brain Struct Funct, 224 (6), 2019.
Input-Specific Synaptic Location and Function of the α5 GABA Receptor Subunit in the Mouse CA1 Hippocampal Neurons.Journal Article
J Neurosci, 39 (5), 2019.
- Dendritic inhibition in hippocampal circuits, from 2020-04-01 to 2025-03-31
- Inhibitory control of hippocampal inhibitory circuits: cell types, neuromodulation and function, from 2019-10-01 to 2024-09-30
- Investigating the contribution of Shank3 in Alzheimer's disease, from 2018-04-01 to 2023-03-31
Recently finished projects
- Mechanisms of dendritic integration and plasticity in GABAergic inhibitory interneurons, from 2015-07-01 to 2021-06-30
- Recherche explorant la relation entre les déficits en inhibition et l'épilepsie afin de comprendre comment garder l'activité du cerveau épileptique en équilibre, from 2020-11-16 to 2021-03-31
- Targeting microglia-synapse interactions to rescue brain circuits elimination and cognitive dysfunction, from 2016-07-01 to 2020-03-31