Sleep Deprivation Alters Hippocampal Dendritic Spines in a Contextual Fear Memory Engram DOI Creative Commons

Matthew Tennin,

Hunter T. Matkins,

Lindsay Rexrode

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: March 5, 2025

Abstract Sleep is critically involved in strengthening memories. However, our understanding of the morphological changes underlying this process still emerging. Recent studies suggest that specific subsets dendritic spines are strengthened during sleep neurons recent learning. Contextual memories associated with traumatic experiences post-traumatic stress disorder (PTSD) and represent learning may be sleep. We tested hypothesis encoding contextual fear selectively Furthermore, we how deprivation after initial impacts following re-exposure to conditioning. used ArcCreER T2 mice visualize encode (Arc+ neurons), concomitantly labeled did not (Arc-neurons). Dendritic branches Arc+ Arc-neurons were sampled using confocal imaging assess spine densities three-dimensional image analysis from either deprived (SD) or control allowed normally. Mushroom displayed decreased density SD mice, indicating upscaling mushroom In comparison, no observed Arc-branches. When animals re-exposed conditioning 4 weeks later, lower both Arc-branches, as well thin Arc-branches trial. Our findings indicate strengthens recently encoded memory, impairs initially later re-exposure. a experience thus viable strategy weakening strength trauma PTSD.

Language: Английский

Forgetting as a form of adaptive engram cell plasticity DOI
Tomás J. Ryan, Paul W. Frankland

Nature reviews. Neuroscience, Journal Year: 2022, Volume and Issue: 23(3), P. 173 - 186

Published: Jan. 13, 2022

Language: Английский

Citations

120
Understanding the physical basis of memory: Molecular mechanisms of the engram DOI Creative Commons
Clara Ortega‐de San Luis, Tomás J. Ryan

Journal of Biological Chemistry, Journal Year: 2022, Volume and Issue: 298(5), P. 101866 - 101866

Published: March 26, 2022

Memory, defined as the storage and use of learned information in brain, is necessary to modulate behavior critical for animals adapt their environments survive. Despite being a cornerstone brain function, questions surrounding molecular cellular mechanisms how encoded, stored, recalled remain largely unanswered. One widely held theory that an engram formed by group neurons are active during learning, which undergoes biochemical physical changes store stable state, later reactivated recall memory. In past decade, development labeling methodologies has proven useful investigate biology memory at levels. Engram technology allows study individual memories associated with particular experiences evolution over time, enough experimental resolution discriminate between different processes: learning (encoding), consolidation (the passage from short-term long-term memories), maintenance brain). Here, we review current understanding formation level focusing on insights provided using technology.

Language: Английский

Citations

61
Neocortical synaptic engrams for remote contextual memories DOI Creative Commons
Jihye Lee, Woong Bin Kim, Eui-Ho Park

et al.

Nature Neuroscience, Journal Year: 2022, Volume and Issue: 26(2), P. 259 - 273

Published: Dec. 23, 2022

While initial encoding of contextual memories involves the strengthening hippocampal circuits, these progressively mature to stabilized forms in neocortex and become less hippocampus dependent. Although it has been proposed that long-term storage may involve enduring synaptic changes neocortical substrates remote have elusive. Here we demonstrate consolidation fear mice correlated with progressive excitatory connections between prefrontal cortical (PFC) engram neurons active during learning reactivated memory recall, whereas extinction weakened those synapses. This synapse-specific plasticity was CREB-dependent required sustained signals, which retrosplenial cortex could convey PFC. Moreover, PFC were strongly connected other recruited recall. Our study suggests circuits can contribute memories.

Language: Английский

Citations

58
Excitation–transcription coupling, neuronal gene expression and synaptic plasticity DOI
Huan Ma, Houda G. Khaled, Xiaohan Wang

et al.

Nature reviews. Neuroscience, Journal Year: 2023, Volume and Issue: 24(11), P. 672 - 692

Published: Sept. 29, 2023

Language: Английский

Citations

35
Hippocampal engram networks for fear memory recruit new synapses and modify pre-existing synapses in vivo DOI Creative Commons
Chaery Lee, Byung Hun Lee,

Hyunsu Jung

et al.

Current Biology, Journal Year: 2023, Volume and Issue: 33(3), P. 507 - 516.e3

Published: Jan. 12, 2023

As basic units of neural networks, ensembles synapses underlie cognitive functions such as learning and memory. These synaptic engrams show elevated density among engram cells following contextual fear memory formation. Subsequent analysis the CA3-CA1 synapse revealed larger spine sizes, connectivity correlated with strength. Here, we elucidate dynamics between CA3 CA1 by tracking identical at multiple time points adapting two-photon microscopy dual-eGRASP technique in vivo. After formation, connections populations are enhanced conjunction synaptogenesis within hippocampal network. However, extinction specifically disappearance to (E-E) synapses. We observed "newly formed" near pre-existing synapses, which clustered after Overall, conclude that E-E key sites for modification during states.

Language: Английский

Citations

30
Stress disrupts engram ensembles in lateral amygdala to generalize threat memory in mice DOI
Sylvie L. Lesuis,

Sungmo Park,

Aijm Van Der Hoorn

et al.

Cell, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 1, 2024

Language: Английский

Citations

12
Interrogating structural plasticity among synaptic engrams DOI Creative Commons
Dong Il Choi, Bong‐Kiun Kaang

Current Opinion in Neurobiology, Journal Year: 2022, Volume and Issue: 75, P. 102552 - 102552

Published: May 19, 2022

Our daily experiences and learnings are stored in the form of memories. These trigger synaptic plasticity persistent structural functional changes neuronal synapses. Recently, cellular studies memory storage engrams have emerged over last decade. Engram cells reflect interconnected neurons via modified However, we were unable to observe arising from past, because it was not possible distinguish synapses between engram cells. To overcome this barrier, dual-eGRASP (enhanced green fluorescent protein reconstitution across partners) technology can label specific among multiple ensembles. Selective labeling elucidated their role by observing according state. Dual-eGRASP extends level introduce era studies. Here, review concept applications dual-eGRASP, including recent that provided visual evidence at synapse.

Language: Английский

Citations

30
Nicotinic acetylcholine receptors and learning and memory deficits in Neuroinflammatory diseases DOI Creative Commons
Valentina Echeverrı́a, Cristhian Mendoza, Alexandre Iarkov

et al.

Frontiers in Neuroscience, Journal Year: 2023, Volume and Issue: 17

Published: May 15, 2023

Animal survival depends on cognitive abilities such as learning and memory to adapt environmental changes. Memory functions require an enhanced activity connectivity of a particular arrangement engram neurons, supported by the concerted action glia, vascular cells. The deterioration cholinergic system is common occurrence in neurological conditions exacerbated aging traumatic brain injury (TBI), posttraumatic stress disorder (PTSD), Alzheimer's disease (AD), Parkinson's (PD). Cotinine modulator with neuroprotective, antidepressant, anti-inflammatory, antioxidant, memory-enhancing effects. Current evidence suggests Cotinine's beneficial effects cognition results from positive modulation α7-nicotinic acetylcholine receptors (nAChRs) inhibition toll-like (TLRs). α7nAChR affects modulating function endothelial, immune, dendritic cells regulates inhibitory excitatory neurotransmission throughout GABA interneurons. In addition, acting α7 nAChRs TLR reduces neuroinflammation inhibiting release pro-inflammatory cytokines immune Also, α7nAChRs stimulate signaling pathways supporting structural, biochemical, electrochemical, cellular changes Central nervous during processes, including Neurogenesis. Here, mechanisms formation well potential preservation diseases are discussed.

Language: Английский

Citations

19
Engram cell connectivity as a mechanism for information encoding and memory function DOI Creative Commons
Clara Ortega‐de San Luis, Maurizio Pezzoli, Esteban Urrieta

et al.

Current Biology, Journal Year: 2023, Volume and Issue: 33(24), P. 5368 - 5380.e5

Published: Nov. 21, 2023

Language: Английский

Citations

19
Reversal of hyperactive higher-order thalamus attenuates defensiveness in a mouse model of PTSD DOI Creative Commons
Kaiwen Xi, Haoxiang Xiao, Xin Huang

et al.

Science Advances, Journal Year: 2023, Volume and Issue: 9(5)

Published: Feb. 3, 2023

Posttraumatic stress disorder (PTSD) is a highly prevalent and debilitating psychiatric disease often accompanied by severe defensive behaviors, preventing individuals from integrating into society. However, the neural mechanisms of defensiveness in PTSD remain largely unknown. Here, we identified that higher-order thalamus, posteromedial complex thalamus (PoM), was overactivated mouse model PTSD, suppressing PoM activity alleviated excessive behaviors. Moreover, found diminished thalamic inhibition derived reticular nucleus major cause hyperactivity mice. Overloaded innervation to downstream cortical area, frontal association cortex, drove abnormal defensiveness. Overall, our study revealed malfunction mediates behaviors highlighted thalamocortical circuit as potential target for treating PTSD-related overreactivity symptoms.

Language: Английский

Citations

17