1
|
Gardner RS, Newman LA, Mohler EG, Tunur T, Gold PE, Korol DL. Aging is not equal across memory systems. Neurobiol Learn Mem 2020; 172:107232. [PMID: 32315762 DOI: 10.1016/j.nlm.2020.107232] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 02/10/2020] [Accepted: 04/13/2020] [Indexed: 12/21/2022]
Abstract
The present experiments compared the effects of aging on learning several hippocampus- and striatum-sensitive tasks in young (3-4 month) and old (24-28 month) male Fischer-344 rats. Across three sets of tasks, aging was accompanied not only by deficits on hippocampal tasks but also by maintained or even enhanced abilities on striatal tasks. On two novel object recognition tasks, rats showed impaired performance on a hippocampal object location task but enhanced performance on a striatal object replacement task. On a dual solution task, young rats predominately used hippocampal solutions and old rats used striatal solutions. In addition, on two maze tasks optimally solved using either hippocampus-sensitive place or striatum-sensitive response strategies, relative to young rats, old rats had impaired learning on the place version but equivalent learning on the response version. Because glucose treatments can reverse deficits in learning and memory across many tasks and contexts, levels of available glucose in the brain may have particular importance in cognitive aging observed across tasks and memory systems. During place learning, training-related rises in extracellular glucose levels were attenuated in the hippocampus of old rats compared to young rats. In contrast, glucose levels in the striatum increased comparably in young and old rats trained on either the place or response task. These extracellular brain glucose responses to training paralleled the impairment in hippocampus-sensitive learning and the sparing of striatum-sensitive learning seen as rats age, suggesting a link between age-related changes in learning and metabolic substrate availability in these brain regions.
Collapse
Affiliation(s)
- R S Gardner
- Department of Biology, Syracuse University, Syracuse, NY 13244, United States.
| | - L A Newman
- Department of Psychological Science, Vassar College, Poughkeepsie, NY 12604, United States
| | - E G Mohler
- Research and Development, AbbVie, North Chicago, IL 60064, United States
| | - T Tunur
- Department of Kinesiology, California State University San Marcos, San Marcos, CA 92096, United States
| | - P E Gold
- Department of Biology, Syracuse University, Syracuse, NY 13244, United States
| | - D L Korol
- Department of Biology, Syracuse University, Syracuse, NY 13244, United States.
| |
Collapse
|
2
|
Korol DL, Gardner RS, Tunur T, Gold PE. Involvement of lactate transport in two object recognition tasks that require either the hippocampus or striatum. Behav Neurosci 2019; 133:176-187. [PMID: 30907617 DOI: 10.1037/bne0000304] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Growing evidence indicates that hippocampal lactate, released from astrocytes, is an important regulator of learning and memory processing. This study evaluated the selective involvement of hippocampal and striatal lactate in two object recognition tasks. The tasks tested recognition memory after a change in location of two target objects (double object location; dOL) or after replacement of familiar targets with two new objects set in the original locations (double object replacement; dOR). Rats received three study sessions across which exploration times decreased. The recognition index was the change in exploration time of both objects on a test trial from the exploration times on the final study trial. We first verified a double dissociation between hippocampus and striatum across these tasks. The sodium channel blocker, lidocaine, was infused into one of the two brain regions after the study sessions and before the test trial. To test the role of neuronal lactate in recognition memory, an inhibitor of the neuronal lactate transporter, α-cyano-4-hydroxycinnamate (4-CIN), was similarly infused. For both drugs, infusions into the hippocampus but not the striatum impaired recognition in the dOL, whereas infusions into the striatum but not hippocampus impaired recognition in the dOR. The findings obtained with 4-CIN demonstrate for the first time the importance of neuronal lactate uptake in the hippocampus and the striatum for object recognition memory processing. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
Collapse
|
3
|
Newman LA, Scavuzzo CJ, Gold PE, Korol DL. Training-induced elevations in extracellular lactate in hippocampus and striatum: Dissociations by cognitive strategy and type of reward. Neurobiol Learn Mem 2017; 137:142-153. [PMID: 27919829 PMCID: PMC5215615 DOI: 10.1016/j.nlm.2016.12.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/27/2016] [Accepted: 12/01/2016] [Indexed: 01/05/2023]
Abstract
Recent evidence suggests that astrocytes convert glucose to lactate, which is released from the astrocytes and supports learning and memory. This report takes a multiple memory perspective to test the role of astrocytes in cognition using real-time lactate measurements during learning and memory. Extracellular lactate levels in the hippocampus or striatum were determined with lactate biosensors while rats were learning place (hippocampus-sensitive) or response (striatum-sensitive) versions of T-mazes. In the first experiment, rats were trained on the place and response tasks to locate a food reward. Extracellular lactate levels in the hippocampus increased beyond those of feeding controls during place training but not during response training. However, striatal lactate levels did not increase beyond those of controls when rats were trained on either the place or the response version of the maze. Because food ingestion itself increased blood glucose and brain lactate levels, the contribution of feeding may have confounded the brain lactate measures. Therefore, we conducted a second similar experiment using water as the reward. A very different pattern of lactate responses to training emerged when water was used as the task reward. First, provision of water itself did not result in large increases in either brain or blood lactate levels. Moreover, extracellular lactate levels increased in the striatum during response but not place learning, whereas extracellular lactate levels in the hippocampus did not differ across tasks. The findings from the two experiments suggest that the relative engagement of the hippocampus and striatum dissociates not only by task but also by reward type. The divergent lactate responses of the hippocampus and striatum in place and response tasks under different reward conditions may reflect ethological constraints tied to foraging for food and water.
Collapse
Affiliation(s)
- Lori A Newman
- Department of Biology, Syracuse University, Syracuse, NY 13224, USA
| | - Claire J Scavuzzo
- Department of Psychology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Paul E Gold
- Department of Biology, Syracuse University, Syracuse, NY 13224, USA
| | - Donna L Korol
- Department of Biology, Syracuse University, Syracuse, NY 13224, USA.
| |
Collapse
|
4
|
Enhancing dopaminergic signaling and histone acetylation promotes long-term rescue of deficient fear extinction. Transl Psychiatry 2016; 6:e974. [PMID: 27922638 PMCID: PMC5315560 DOI: 10.1038/tp.2016.231] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 08/17/2016] [Accepted: 08/18/2016] [Indexed: 01/04/2023] Open
Abstract
Extinction-based exposure therapy is used to treat anxiety- and trauma-related disorders; however, there is the need to improve its limited efficacy in individuals with impaired fear extinction learning and to promote greater protection against return-of-fear phenomena. Here, using 129S1/SvImJ mice, which display impaired fear extinction acquisition and extinction consolidation, we revealed that persistent and context-independent rescue of deficient fear extinction in these mice was associated with enhanced expression of dopamine-related genes, such as dopamine D1 (Drd1a) and -D2 (Drd2) receptor genes in the medial prefrontal cortex (mPFC) and amygdala, but not hippocampus. Moreover, enhanced histone acetylation was observed in the promoter of the extinction-regulated Drd2 gene in the mPFC, revealing a potential gene-regulatory mechanism. Although enhancing histone acetylation, via administering the histone deacetylase (HDAC) inhibitor MS-275, does not induce fear reduction during extinction training, it promoted enduring and context-independent rescue of deficient fear extinction consolidation/retrieval once extinction learning was initiated as shown following a mild conditioning protocol. This was associated with enhanced histone acetylation in neurons of the mPFC and amygdala. Finally, as a proof-of-principle, mimicking enhanced dopaminergic signaling by L-dopa treatment rescued deficient fear extinction and co-administration of MS-275 rendered this effect enduring and context-independent. In summary, current data reveal that combining dopaminergic and epigenetic mechanisms is a promising strategy to improve exposure-based behavior therapy in extinction-impaired individuals by initiating the formation of an enduring and context-independent fear-inhibitory memory.
Collapse
|
5
|
Korol DL, Pisani SL. Estrogens and cognition: Friends or foes?: An evaluation of the opposing effects of estrogens on learning and memory. Horm Behav 2015; 74:105-15. [PMID: 26149525 PMCID: PMC4573330 DOI: 10.1016/j.yhbeh.2015.06.017] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 06/19/2015] [Accepted: 06/25/2015] [Indexed: 12/19/2022]
Abstract
This article is part of a Special Issue "Estradiol and cognition". Estrogens are becoming well known for their robust enhancement on cognition particularly for learning and memory that relies upon functioning of the hippocampus and related neural systems. What is also emerging is that estrogen modulation of cognition is not uniform, at times enhancing yet at other times impairing learning. This review explores the bidirectional effects of estrogens on learning from a multiple memory systems view, focusing on the hippocampus and striatum, whereby modulation by estrogens sorts according to task attributes and neural systems engaged during cognition. We highlight our findings showing that the ability to solve hippocampus-sensitive tasks typically improves under relatively high estrogen status while the ability to solve striatum-sensitive tasks degrades with estrogen exposures. Though constrained by dose and timing of exposure, these opposing enhancements and impairments of cognition can be observed following treatments with different estrogenic compounds including the hormone estradiol, the isoflavone genistein found in soybeans, and agonists that are selective for specific estrogen receptors, suggesting that activation of a single receptor type is sufficient to produce the observed shifts in learning strategies. Using this multi-dimensional framework will allow us to extend our thinking of the relationship between estrogens and cognition to other brain regions and cognitive functions.
Collapse
Affiliation(s)
- Donna L Korol
- Department of Biology, Syracuse University, Department of Neuroscience and Physiology, SUNY-Upstate Medical University, Syracuse, NY 13244, USA.
| | - Samantha L Pisani
- Neuroscience Program and Medical Scholars Program, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| |
Collapse
|
6
|
Mizumori SJY, Jo YS. Homeostatic regulation of memory systems and adaptive decisions. Hippocampus 2014; 23:1103-24. [PMID: 23929788 PMCID: PMC4165303 DOI: 10.1002/hipo.22176] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2013] [Indexed: 11/07/2022]
Abstract
While it is clear that many brain areas process mnemonic information, understanding how their interactions result in continuously adaptive behaviors has been a challenge. A homeostatic-regulated prediction model of memory is presented that considers the existence of a single memory system that is based on a multilevel coordinated and integrated network (from cells to neural systems) that determines the extent to which events and outcomes occur as predicted. The “multiple memory systems of the brain” have in common output that signals errors in the prediction of events and/or their outcomes, although these signals differ in terms of what the error signal represents (e.g., hippocampus: context prediction errors vs. midbrain/striatum: reward prediction errors). The prefrontal cortex likely plays a pivotal role in the coordination of prediction analysis within and across prediction brain areas. By virtue of its widespread control and influence, and intrinsic working memory mechanisms. Thus, the prefrontal cortex supports the flexible processing needed to generate adaptive behaviors and predict future outcomes. It is proposed that prefrontal cortex continually and automatically produces adaptive responses according to homeostatic regulatory principles: prefrontal cortex may serve as a controller that is intrinsically driven to maintain in prediction areas an experience-dependent firing rate set point that ensures adaptive temporally and spatially resolved neural responses to future prediction errors. This same drive by prefrontal cortex may also restore set point firing rates after deviations (i.e. prediction errors) are detected. In this way, prefrontal cortex contributes to reducing uncertainty in prediction systems. An emergent outcome of this homeostatic view may be the flexible and adaptive control that prefrontal cortex is known to implement (i.e. working memory) in the most challenging of situations. Compromise to any of the prediction circuits should result in rigid and suboptimal decision making and memory as seen in addiction and neurological disease. © 2013 The Authors. Hippocampus Published by Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Sheri J Y Mizumori
- This is an open access article under the terms of the Creative Commons Attribution-Non-Commercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. Psychology Department, University of Washington, Seattle, Washington
| | | |
Collapse
|
7
|
Korol DL, Gold PE, Scavuzzo CJ. Use it and boost it with physical and mental activity. Hippocampus 2014; 23:1125-35. [PMID: 23996382 DOI: 10.1002/hipo.22197] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 08/26/2013] [Indexed: 01/24/2023]
Abstract
One of the now classic tenets of neuroscience is that the brain retains a substantial amount of structural and functional plasticity throughout adulthood and old age. Enriching experiences that stimulate physical and mental activity produce robust changes in subsequent behaviors, including learning and memory, that tap a wide range of neural systems. In this article, we review evidence for cognitive priming with physical and mental exercise through a memory systems lens and present brain-derived neurotrophic factor (BDNF) signaling as one candidate neural mechanism for experience-dependent modulation of learning and memory. We highlight our recent findings showing that priming with voluntary exercise or with spontaneous alternation, a working memory task, enhances new learning of hippocampus-sensitive place, or striatum-sensitive response tasks. Blocking BDNF signaling with infusions of a BDNF receptor inhibitor into hippocampus or striatum just before training on place or response tasks, respectively, abrogated the benefits of priming regardless of the type of priming experience. These results suggest that enhanced BDNF signaling during learning may itself produce the cognitive benefits afforded by prior physical or mental activity.
Collapse
Affiliation(s)
- Donna L Korol
- Department of Biology, Syracuse University, Syracuse, New York
| | | | | |
Collapse
|
8
|
Kathirvelu B, East BS, Hill AR, Smith CA, Colombo PJ. Lentivirus-mediated chronic expression of dominant-negative CREB in the dorsal hippocampus impairs memory for place learning and contextual fear conditioning. Neurobiol Learn Mem 2013; 99:10-6. [PMID: 23110949 DOI: 10.1016/j.nlm.2012.10.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 09/18/2012] [Accepted: 10/15/2012] [Indexed: 12/30/2022]
Abstract
Extensive research has shown that the transcription factor CREB has an important role during memory formation. In the present study, we tested a new method for chronic, stable expression of a dominant-negative form of CREB (mCREB) in the dorsal hippocampus using lentiviral vectors. In specific, we tested whether lentivirus-mediated chronic expression of mutant CREB impairs memory for two hippocampus-dependent tasks - place training in the water maze and contextual fear conditioning. Two weeks following intra-hippocampal infusion, experimental (mCREB) and control (LacZ and saline) rats were trained for 30 trials in one session on a place task in a water plus-maze and tested for an additional 30 trials on day 2 and on day 7. On day 8, all rats were trained on a contextual fear conditioning task and tested 24h later. For place learning, there was no difference between treatment groups on day 1, indicating that treatment with the lentiviral vectors did not alter performance or acquisition of the task. In comparisons with controls, mCREB-treated rats were not significantly impaired on day 2, overall, but they showed significant impairment on day 7. Contextual fear memory was impaired in mCREB-infused rats in comparison with controls. At the end of the experiment, total CREB and phosphorylated CREB protein were measured by western blot. Levels of total CREB were increased by approximately 40% among mCREB-treated rats in comparisons with controls, whereas levels of pCREB did not differ between groups, suggesting that the treatment caused significant expression of mCREB. In addition, mCREB infused rats showed a significant reduction in the pCREB to CREB ratio in comparison with controls, suggesting that the memory deficit seen in mCREB rats is most likely due to disruption of gene regulation caused by expression of mutant CREB. Taken together, the present results show that lentivirus expressing mCREB can be used to effectively alter CREB function within the hippocampus and that the treatment impairs memory for hippocampus-dependent tasks.
Collapse
|
9
|
Similarities and differences between the brain networks underlying allocentric and egocentric spatial learning in rat revealed by cytochrome oxidase histochemistry. Neuroscience 2012; 223:174-82. [DOI: 10.1016/j.neuroscience.2012.07.066] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 07/27/2012] [Accepted: 07/30/2012] [Indexed: 11/18/2022]
|
10
|
G9a/GLP histone lysine dimethyltransferase complex activity in the hippocampus and the entorhinal cortex is required for gene activation and silencing during memory consolidation. J Neurosci 2012; 32:5440-53. [PMID: 22514307 DOI: 10.1523/jneurosci.0147-12.2012] [Citation(s) in RCA: 167] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Learning triggers alterations in gene transcription in brain regions such as the hippocampus and the entorhinal cortex (EC) that are necessary for long-term memory (LTM) formation. Here, we identify an essential role for the G9a/G9a-like protein (GLP) lysine dimethyltransferase complex and the histone H3 lysine 9 dimethylation (H3K9me2) marks it catalyzes, in the transcriptional regulation of genes in area CA1 of the rat hippocampus and the EC during memory consolidation. Contextual fear learning increased global levels of H3K9me2 in area CA1 and the EC, with observable changes at the Zif268, DNMT3a, BDNF exon IV, and cFOS gene promoters, which occurred in concert with mRNA expression. Inhibition of G9a/GLP in the EC, but not in the hippocampus, enhanced contextual fear conditioning relative to control animals. The inhibition of G9a/GLP in the EC induced several histone modifications that include not only methylation but also acetylation. Surprisingly, we found that downregulation of G9a/GLP activity in the EC enhanced H3K9me2 in area CA1, resulting in transcriptional silencing of the non-memory permissive gene COMT in the hippocampus. In addition, synaptic plasticity studies at two distinct EC-CA1 cellular pathways revealed that G9a/GLP activity is critical for hippocampus-dependent long-term potentiation initiated in the EC via the perforant pathway, but not the temporoammonic pathway. Together, these data demonstrate that G9a/GLP differentially regulates gene transcription in the hippocampus and the EC during memory consolidation. Furthermore, these findings support the possibility of a role for G9a/GLP in the regulation of cellular and molecular cross talk between these two brain regions during LTM formation.
Collapse
|
11
|
Zeitlin R, Patel S, Burgess S, Arendash GW, Echeverria V. Caffeine induces beneficial changes in PKA signaling and JNK and ERK activities in the striatum and cortex of Alzheimer's transgenic mice. Brain Res 2011; 1417:127-36. [PMID: 21907331 DOI: 10.1016/j.brainres.2011.08.036] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 07/26/2011] [Accepted: 08/14/2011] [Indexed: 02/07/2023]
Abstract
Caffeine intake has been associated with a lower incidence of Alzheimer's disease (AD) in humans. In AD mouse models, caffeine significantly decreases senile plaques and amyloid beta (Aβ) levels while also protecting against or reversing cognitive impairment. To understand the mechanism(s) underlying the protective effects of caffeine against AD pathology, we investigated the effects of a two-week treatment with caffeine (3mg/day) in transgenic (APPswe) mice and non-transgenic (NT) mice on signaling factors involved in neuronal plasticity and survival. We evaluated cAMP-dependent protein kinase A (PKA), phospho-cyclic AMP response-element binding protein (phospho-CREB), and the pro-apoptotic protein kinases extracellular signal-regulated kinase 1/2 (phospho-ERK) and phospho-c-Jun N-terminal kinase 1 (phospho-JNK) in the striatum and frontal cortex of caffeine-treated mice. In the striatum, APPswe control mice exhibited a significant decrease in phospho-CREB, as well as significant increases in phospho-JNK and phospho-ERK in comparison to NT mice. Caffeine treatment stimulated PKA activity, increased phospho-CREB levels, and decreased phospho-JNK and phospho-ERK expression in the striatum of APPswe mice, all of which are thought to be beneficial changes for brain function. Even caffeine-treated NT mice exhibited some of these changes in striatum. In the frontal cortex, caffeine did not significantly increase phospho-CREB and PKA activity, but significantly reduced phospho-JNK and phospho-ERK expression in both APPswe and NT mice. These results suggest that caffeine shifts the balance between neurodegeneration and neuronal survival toward the stimulation of pro-survival cascades and inhibition of pro-apoptotic pathways in the striatum and/or cortex, which may contribute to its beneficial effects against AD.
Collapse
Affiliation(s)
- Ross Zeitlin
- Research and Development, Department of Veterans Affairs, Bay Pines VA Healthcare System, Bay Pines, FL 33744, USA
| | | | | | | | | |
Collapse
|
12
|
Havekes R, Abel T, Van der Zee EA. The cholinergic system and neostriatal memory functions. Behav Brain Res 2010; 221:412-23. [PMID: 21129408 DOI: 10.1016/j.bbr.2010.11.047] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Revised: 11/19/2010] [Accepted: 11/23/2010] [Indexed: 11/25/2022]
Abstract
The striatum is one of the major forebrain regions that strongly expresses muscarinic and nicotinic cholinergic receptors. This article reviews the current knowledge and our new findings about the striatal cholinoceptive organization and its role in a variety of cognitive functions. Pharmacological and genetic manipulations have indicated that the cholinergic and dopaminergic system in the striatum modulate each other's function. In addition to modulating the dopaminergic system, nicotinic cholinergic receptors facilitate GABA release, whereas muscarinic receptors attenuate GABA release. The striatal cholinergic system has also been implicated in various cognitive functions including procedural learning and intradimensional set shifting. Together, these data indicate that the cholinergic system in the striatum is involved in a diverse set of cognitive functions through interactions with other neurotransmitter systems including the dopaminergic and GABAergic systems.
Collapse
Affiliation(s)
- Robbert Havekes
- Department of Biology, University of Pennsylvania, 433 S University Avenue, Philadelphia, PA 19104, USA.
| | | | | |
Collapse
|
13
|
Whittle N, Hauschild M, Lubec G, Holmes A, Singewald N. Rescue of impaired fear extinction and normalization of cortico-amygdala circuit dysfunction in a genetic mouse model by dietary zinc restriction. J Neurosci 2010; 30:13586-96. [PMID: 20943900 PMCID: PMC3149823 DOI: 10.1523/jneurosci.0849-10.2010] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Revised: 05/31/2010] [Accepted: 07/16/2010] [Indexed: 11/21/2022] Open
Abstract
Fear extinction is impaired in neuropsychiatric disorders, including posttraumatic stress disorder. Identifying drugs that facilitate fear extinction in animal models provides leads for novel pharmacological treatments for these disorders. Zinc (Zn) is expressed in neurons in a cortico-amygdala circuit mediating fear extinction, and modulates neurotransmitter systems regulating extinction. We previously found that the 129S1/SvImJ mouse strain (S1) exhibited a profound impairment in fear extinction, coupled with abnormalities in the activation of the extinction circuit. Here, we tested the role of Zn in fear extinction in S1 and C57BL/6N reference strain (B6) by feeding the mice a Zn-restricted diet (ZnR) and testing for fear extinction, as well as neuronal activation of the extinction circuit via quantification of the immediate-early genes c-Fos and Zif268. Results showed that (preconditioning or postconditioning) ZnR completely rescued deficient extinction learning and long-term extinction retrieval in S1 and expedited extinction learning in B6, without affecting fear acquisition or fear expression. The extinction-facilitating effects of ZnR were associated with the normalization of Zif268 and/or c-Fos expression in cortico-amygdala regions of S1. Specifically, ZnR increased activity in infralimbic cortex, lateral and basolateral amygdala nuclei, and lateral central amygdala nucleus, and decreased activity in prelimbic and insular cortices and medial central amygdala nucleus. ZnR also increased activation in the main intercalated nucleus and decreased activation of the medial paracapsular intercalated mass in S1. Our findings reveal a novel role for Zn in fear extinction and further support the utility of the S1 model for identifying extinction facilitating drugs.
Collapse
Affiliation(s)
- Nigel Whittle
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Markus Hauschild
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, A-6020 Innsbruck, Austria
| | - Gert Lubec
- Department of Pediatrics, Medical University of Vienna, A-1090 Vienna, Austria, and
| | - Andrew Holmes
- Section on Behavioral Science and Genetics, Laboratory for Integrative Neuroscience, National Institute on Alcoholism and Alcohol Abuse, National Institutes of Health, Bethesda, Maryland 20852
| | - Nicolas Singewald
- Department of Pharmacology and Toxicology, Institute of Pharmacy, Center for Molecular Biosciences Innsbruck, University of Innsbruck, A-6020 Innsbruck, Austria
| |
Collapse
|
14
|
Burger T, Lucová M, Moritz RE, Oelschläger HHA, Druga R, Burda H, Wiltschko W, Wiltschko R, Nemec P. Changing and shielded magnetic fields suppress c-Fos expression in the navigation circuit: input from the magnetosensory system contributes to the internal representation of space in a subterranean rodent. J R Soc Interface 2010; 7:1275-92. [PMID: 20219838 DOI: 10.1098/rsif.2009.0551] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The neural substrate subserving magnetoreception and magnetic orientation in mammals is largely unknown. Previous experiments have demonstrated that the processing of magnetic sensory information takes place in the superior colliculus. Here, the effects of magnetic field conditions on neuronal activity in the rodent navigation circuit were assessed by quantifying c-Fos expression. Ansell's mole-rats (Fukomys anselli), a mammalian model to study the mechanisms of magnetic compass orientation, were subjected to natural, periodically changing, and shielded magnetic fields while exploring an unfamiliar circular arena. In the undisturbed local geomagnetic field, the exploration of the novel environment and/or nesting behaviour induced c-Fos expression throughout the head direction system and the entorhinal-hippocampal spatial representation system. This induction was significantly suppressed by exposure to periodically changing and/or shielded magnetic fields; discrete decreases in c-Fos were seen in the dorsal tegmental nucleus, the anterodorsal and the laterodorsal thalamic nuclei, the postsubiculum, the retrosplenial and entorhinal cortices, and the hippocampus. Moreover, in inactive animals, magnetic field intensity manipulation suppressed c-Fos expression in the CA1 and CA3 fields of the hippocampus and the dorsal subiculum, but induced expression in the polymorph layer of the dentate gyrus. These findings suggest that key constituents of the rodent navigation circuit contain populations of neurons responsive to magnetic stimuli. Thus, magnetic information may be integrated with multimodal sensory and motor information into a common spatial representation of allocentric space within this circuit.
Collapse
Affiliation(s)
- Tomás Burger
- Department of Zoology, Faculty of Science Charles University in Prague, Vinicna 7, CZ-12844 Praha 2, Czech Republic
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
|
16
|
Molecular mechanisms underlying synergistic effects of SSRI–antipsychotic augmentation in treatment of negative symptoms in schizophrenia. J Neural Transm (Vienna) 2009; 116:1529-41. [DOI: 10.1007/s00702-009-0255-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2008] [Accepted: 06/05/2009] [Indexed: 01/08/2023]
|
17
|
Packard MG. Exhumed from thought: Basal ganglia and response learning in the plus-maze. Behav Brain Res 2009; 199:24-31. [DOI: 10.1016/j.bbr.2008.12.013] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2008] [Revised: 12/05/2008] [Accepted: 12/08/2008] [Indexed: 12/30/2022]
|
18
|
Panagiotaropoulos T, Diamantopoulou A, Stamatakis A, Dimitropoulou M, Stylianopoulou F. Learning of a T-maze by rat pups when contact with the mother is either permitted or denied. Neurobiol Learn Mem 2009; 91:2-12. [DOI: 10.1016/j.nlm.2008.09.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 09/16/2008] [Accepted: 09/18/2008] [Indexed: 10/21/2022]
|
19
|
The molecular cascades of long-term potentiation underlie memory consolidation of one-trial avoidance in the CA1 region of the dorsal hippocampus, but not in the basolateral amygdala or the neocortex. Neurotox Res 2008; 14:273-94. [DOI: 10.1007/bf03033816] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
20
|
Liu J, Song J. A novel nucleolar transcriptional activator ApLLP for long-term memory formation is intrinsically unstructured but functionally active. Biochem Biophys Res Commun 2007; 366:585-91. [PMID: 18078811 DOI: 10.1016/j.bbrc.2007.12.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2007] [Accepted: 12/04/2007] [Indexed: 11/20/2022]
Abstract
A novel Aplysia nucleolar protein ApLLP has been recently characterized to be a transcriptional activator that binds to the cAMP-response element (CRE) and thus induces ApC/EBP expression required for establishing long-term memory. So far, no structural information is available for both ApLLP and its homologs. Here, we expressed the entire ApLLP and its two dissected fragments, followed by structural and binding studies using CD and NMR spectroscopy. The study leads to two interesting findings: (1) all three ApLLP proteins are highly disordered, owning no predominant secondary and tertiary structures; (2) ApLLP is capable of binding the CRE DNA element but this induces no significant change in its secondary and tertiary structures. Intriguingly, it appears that the DNA-binding residues are mainly located on the C-half of the ApLLP molecule. Taken together, our results define ApLLP as an intrinsically unstructured protein and may bear important implications in understanding the molecular mechanism underlying ApLLP functions.
Collapse
Affiliation(s)
- Jingxian Liu
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore
| | | |
Collapse
|
21
|
Smith CA, Countryman RA, Sahuque LL, Colombo PJ. Time-courses of Fos expression in rat hippocampus and neocortex following acquisition and recall of a socially transmitted food preference. Neurobiol Learn Mem 2007; 88:65-74. [PMID: 17448703 DOI: 10.1016/j.nlm.2007.03.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2007] [Revised: 03/06/2007] [Accepted: 03/06/2007] [Indexed: 11/24/2022]
Abstract
The present study examined expression of the immediate-early gene, c-Fos, following acquisition, 48-h (recent) recall, and 1-week (remote) recall of a socially transmitted food preference (STFP) in multiple brain regions implicated in learning and memory. In comparisons with controls, trained Long-Evans rats had increased Fos immunoreactivity in the ventral hippocampus following acquisition and recent recall. In the parahippocampal cortices, Fos was increased in the lateral entorhinal cortex after acquisition. In the orbitofrontal cortex, increased Fos immunoreactivity was observed in the lateral orbital cortex following both recent and remote recall and in the ventral orbital cortex following remote recall, indicating a role for the orbitofrontal cortex in the remote recall of STFP memory. In contrast, in the medial prefrontal cortex, increased Fos-ir was found following acquisition in the prelimbic cortex and following recent recall in the prelimbic and infralimbic cortices. No differences in Fos expression were found between trained rats and controls in the dorsal hippocampus, posterior parietal cortex, or amygdala. The present findings support a time-limited role of the hippocampus in the acquisition and recall of STFP memory and implicate neocortical regions involved in STFP acquisition, recent, and remote recall.
Collapse
Affiliation(s)
- Clayton A Smith
- Neuroscience Program, Tulane University, New Orleans, LA 70118, USA
| | | | | | | |
Collapse
|
22
|
Brightwell JJ, Smith CA, Neve RL, Colombo PJ. Long-term memory for place learning is facilitated by expression of cAMP response element-binding protein in the dorsal hippocampus. Learn Mem 2007; 14:195-9. [PMID: 17351144 DOI: 10.1101/lm.395407] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Extensive research has shown that the hippocampus is necessary for consolidation of long-term spatial memory in rodents. We reported previously that rats using a place strategy to solve a cross maze task showed sustained phosphorylation of hippocampus cyclic AMP response element-binding protein (CREB), a transcription factor implicated in long-term memory formation. In the current study, we used viral vector-mediated gene transfer to test the hypothesis that formation of long-term memory for place learning can be facilitated by increasing levels of CREB in the dorsal hippocampus. Three days after intrahippocampus infusion, experimental (HSV-CREB) and control (HSV-LacZ; saline) rats were trained during a single session on a place task in a water cross maze. Rats were tested for memory 5 d later. Rats in all groups showed short-term memory, and there were no significant differences among treatment groups during acquisition. However, only HSV-CREB-infused rats showed significant savings between training and test, while HSV-LacZ- and saline-treated rats did not. Quantitative Western blotting confirmed that levels of dorsal hippocampus CREB were increased during training in rats infused with HSV-CREB in comparisons with controls. The present results show that formation of long-term memory can be facilitated by increasing levels of hippocampus CREB protein.
Collapse
|
23
|
Kim H, Lee SH, Han JH, Lee JA, Cheang YH, Chang DJ, Lee YS, Kaang BK. A nucleolar protein ApLLP induces ApC/EBP expression required for long-term synaptic facilitation in aplysia neurons. Neuron 2006; 49:707-18. [PMID: 16504946 DOI: 10.1016/j.neuron.2006.01.035] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Revised: 06/07/2005] [Accepted: 01/26/2006] [Indexed: 10/25/2022]
Abstract
In Aplysia, long-term synaptic plasticity is induced by serotonin (5-HT) or neural activity and requires gene expression. Here, we demonstrate that ApLLP, a novel nucleolus protein, is critically involved in both long-term facilitation (LTF) and behavioral sensitization. Membrane depolarization induced ApLLP expression, which activated ApC/EBP expression through a direct binding to CRE. LTF was produced by a single pulse of 5-HT 30 min after the membrane depolarization. This LTF was blocked when either ApLLP or ApC/EBP were blocked by specific antibodies. In contrast, ApLLP overexpression induced LTF in response to a single 5-HT treatment. Simultaneously, a siphon noxious stimulus (SNS) to intact Aplysia induced ApLLP and ApC/EBP expression, and single tail shock 30 min after SNS transformed short-term sensitization to long-term sensitization of siphon withdrawal reflex. These results suggest that ApLLP is an activity-dependent transcriptional activator that switches short-term facilitation to long-term facilitation.
Collapse
Affiliation(s)
- Hyoung Kim
- National Research Laboratory, Institute of Molecular Biology and Genetics, School of Biological Sciences, College of Natural Sciences, Seoul National University, San 56-1 Silim-dong Kwanak-gu, Seoul 151-742, Korea
| | | | | | | | | | | | | | | |
Collapse
|
24
|
Martel G, Millard A, Jaffard R, Guillou JL. Stimulation of hippocampal adenylyl cyclase activity dissociates memory consolidation processes for response and place learning. Learn Mem 2006; 13:342-8. [PMID: 16741285 PMCID: PMC1475816 DOI: 10.1101/lm.149506] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2005] [Accepted: 02/21/2006] [Indexed: 11/24/2022]
Abstract
Procedural and declarative memory systems are postulated to interact in either a synergistic or a competitive manner, and memory consolidation appears to be a highly critical stage for this process. However, the precise cellular mechanisms subserving these interactions remain unknown. To investigate this issue, 24-h retention performances were examined in mice given post-training intrahippocampal injections of forskolin (FK) aiming at stimulating hippocampal adenylyl cyclases (ACs). The injection was given at different time points over a period of 9 h following acquisition in either an appetitive bar-pressing task or water-maze tasks challenging respectively "response memory" and "place memory." Retention testing (24 h) showed that FK injection altered memory formation only when given within a 3- to 6-h time window after acquisition but yielded opposite memory effects as a function of task demands. Retention of the spatial task was impaired, whereas retention of both the cued-response in the water maze and the rewarded bar-press response were improved. Intrahippocampal injections of FK produced an increase in pCREB immunoreactivity, which was strictly limited to the hippocampus and lasted less than 2 h, suggesting that early effects (0-2 h) of FK-induced cAMP/CREB activation can be distinguished from late effects (3-6 h). These results delineate a consolidation period during which specific cAMP levels in the hippocampus play a crucial role in enhancing memory processes mediated by other brain regions (e.g., dorsal or ventral striatum) while eliminating interference by the formation of hippocampus-dependent memory.
Collapse
Affiliation(s)
- Guillaume Martel
- Laboratoire de Neurosciences Cognitives, Université Bordeaux I, Centre Nationale de la Recherche Scientifique Unite Mixte de Recherche (CNRS UMR) 5106, 33405 Talence cedex, France
| | | | | | | |
Collapse
|
25
|
Pych JC, Chang Q, Colon-Rivera C, Haag R, Gold PE. Acetylcholine release in the hippocampus and striatum during place and response training. Learn Mem 2006; 12:564-72. [PMID: 16322358 PMCID: PMC1356173 DOI: 10.1101/lm.33105] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
These experiments examined the release of acetylcholine in the hippocampus and striatum when rats were trained, within single sessions, on place or response versions of food-rewarded mazes. Microdialysis samples of extra-cellular fluid were collected from the hippocampus and striatum at 5-min increments before, during, and after training. These samples were later analyzed for ACh content using HPLC methods. In Experiment 1, ACh release in both the hippocampus and striatum increased during training on both the place and response tasks. The magnitude of increase of training-related ACh release in the striatum was greater in rats trained on the response task than in rats trained on the place task, while the magnitude of ACh release in the hippocampus was comparable in the two tasks. Experiment 2 tested the possibility that the hippocampus was engaged and participated in learning the response task, as well as the place task, because of the availability of extra-maze cues. Rats were trained on a response version of a maze under either cue-rich or cue-poor conditions. The findings indicate that ACh release in the hippocampus increased similarly under both cue conditions, but declined during training on the cue-poor condition, when spatial processing by the hippocampus would not be suitable for solving the maze. In addition, high baseline levels of ACh release in the hippocampus predicted rapid learning in the cue-rich condition and slow learning in the cue-poor condition. These findings suggest that ACh release in the hippocampus augments response learning when extra-maze cues can be used to solve the maze but impairs response learning when extra-maze cues are not available for use in solving the maze.
Collapse
Affiliation(s)
- Jason C Pych
- Department of Psychology, University of Illinois at Urbana-Champaign, Illinois 61820, USA
| | | | | | | | | |
Collapse
|
26
|
Moncada D, Viola H. Phosphorylation state of CREB in the rat hippocampus: a molecular switch between spatial novelty and spatial familiarity? Neurobiol Learn Mem 2006; 86:9-18. [PMID: 16426870 DOI: 10.1016/j.nlm.2005.12.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2005] [Revised: 11/16/2005] [Accepted: 12/08/2005] [Indexed: 11/18/2022]
Abstract
The activation of cAMP response element-binding protein (CREB) after a learning experience is a common feature in the formation of several associative memories. We recently demonstrated that the increase in the hippocampal phosphorylated CREB (pCREB) levels 1 h after a short exploration of an open field (OF) was associated to detection of spatial novelty and was not related to the memory formation of habituation in this non-associative learning paradigm. Moreover, after a long training of three OF sessions, hippocampal pCREB levels were below to that observed in control rats. The present results show that such decrease does not correlate with memory retrieval or improvement in long-term memory of habituation. Instead, it is associated with the familiarity to the arena. Our experiments revealed that the relevant variable to induce CREB deactivation was the prolonged exploration of the arena (30 min). A 15 min OF exploration was ineffective. Furthermore, the last 5 min period of a prolonged exploration was crucial to change CREB phosphorylation state: when exploration took place in a novel arena the level of pCREB increased; in contrast, when it was performed in the familiar OF, pCREB levels decreased. Taken as a whole, our results suggest that CREB phosphorylation state in the hippocampus switches in response to exposure to a novel or to a familiar spatial environment.
Collapse
Affiliation(s)
- Diego Moncada
- Instituto de Biología Celular y Neurociencias, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | | |
Collapse
|
27
|
Gold PE. Coordination of multiple memory systems. Neurobiol Learn Mem 2005; 82:230-42. [PMID: 15464406 DOI: 10.1016/j.nlm.2004.07.003] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2004] [Revised: 07/08/2004] [Accepted: 07/14/2004] [Indexed: 11/17/2022]
Abstract
On the basis of lesions of different brain areas, several neural systems appear to be important for processing information regarding different types of learning and memory. This paper examines the development of pharmacological and neurochemical approaches to multiple memory systems from past studies of modulation of memory formation. The findings suggest that peripheral neuroendocrine mechanisms that regulate memory processing may target their actions toward those neural systems most engaged in the processing of learning and memory. In addition, measurements of acetylcholine release in different memory systems reveals extensive interactions between memory systems, some cooperative and some competitive. These results imply that many neural systems, often characterized as relatively independent, may in fact interact extensively, blurring the dependencies of different memory tasks on specific neural systems.
Collapse
Affiliation(s)
- Paul E Gold
- Departments of Psychology and Psychiatry, Neuroscience Program and the Initiative on Aging, University of Illinois, Urbana-Champaign, IL 61820, USA.
| |
Collapse
|