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Lee SY, Cho WH, Lee YS, Han JS. Impact of Chronic Stress on the Spatial Learning and GR-PKAc-NF-κB Signaling in the Hippocampus and Cortex in Rats Following Cholinergic Depletion. Mol Neurobiol 2017; 55:3976-3989. [PMID: 28551869 DOI: 10.1007/s12035-017-0620-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/12/2017] [Indexed: 12/21/2022]
Abstract
Studies have shown that the removal of the cholinergic innervation to the hippocampus induces dysfunction of the hypothalamic-pituitary-adrenocortical axis and decreases the number of glucocorticoid receptors (GRs). Subsequent studies have revealed that the loss of cholinergic input to the hippocampus reduces the expression of GRs and activates nuclear factor-kappa B (NF-κB) signaling through interactions with the cytoplasmic catalytic subunit of protein kinase A (PKAc). We examined the effects of chronic stress on cognitive status and GR-PKAc-NF-κB signaling in rats with a loss of cholinergic input to the hippocampus and cortex. Male Sprague-Dawley rats received 192 IgG-saporin injections to selectively eliminate cholinergic neurons in their basal forebrain. Two weeks later, rats were subjected to 1 h of restraint stress per day for 14 days. Rats subjected to both chronic stress and cholinergic depletion showed more severe memory impairments compared to those that received either treatment alone. The reduction in nuclear GR levels induced by cholinergic depletion was unaffected by chronic stress. The activation of NF-κB signaling in the hippocampus and the cerebral cortex induced by cholinergic depletion was augmented by chronic stress, resulting in the increased expression of pro-inflammatory markers, such as inducible nitric oxide synthase and cyclooxygenase-2. The activation of NF-κB induced by cholinergic depletion appears to be aggravated by chronic stress, and this might explain the increased susceptibility of patients with Alzheimer's disease to stress since activation of NF-κB is associated with stress.
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Affiliation(s)
- Sun-Young Lee
- Department of Biological Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Woo-Hyun Cho
- Department of Biological Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Yo-Seob Lee
- Department of Biological Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea
| | - Jung-Soo Han
- Department of Biological Sciences, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 05029, Republic of Korea.
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Vicens P, Heredia L, Torrente M, Domingo JL. Behavioural effects of PNU-282987 and stress in an animal model of Alzheimer's disease. Psychogeriatrics 2017; 17:33-42. [PMID: 26817787 DOI: 10.1111/psyg.12189] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/11/2015] [Accepted: 12/17/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND Cholinergic deficits play an important role in both cognitive and behavioural alterations in Alzheimer's disease. This study was aimed at evaluating the possible therapeutic role of PNU-282987 (PNU), an α7 nicotinic cholinergic receptor agonist, and the possible effects of stress in precipitating the onset of behavioural deficits in animals with susceptibility to Alzheimer's disease. METHODS B6C3-Tg mice with susceptibility to Alzheimer's disease and wild-type mice either with or without restraint stress received 0- or 1-mg/kg PNU. At 12 months old, mice were evaluated for activity levels, anxiety-like levels, and spatial learning and memory. RESULTS Data did not show the effects of PNU on activity and anxiety-like behaviour. No effect of PNU on acquisition of a spatial learning task was detected, but a reversal of stress effects on retention in the Morris water maze was observed in transgenic mice. CONCLUSIONS Further studies are needed in order to better understand the role of α7 nicotinic cholinergic receptor agonists in motor activity, anxiety, and spatial learning and memory and to develop more accurate pharmacological treatment of psychopathological diseases.
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Affiliation(s)
- Paloma Vicens
- Department of Psychology, Universitat Rovira i Virgili, Tarragona, Spain.,Research Center in Behavioral Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain.,Laboratory of Toxicology and Environmental Health, School of Medicine, Institut d'Investigació Sanitària Pere Virgili (IISPV), Universitat Rovira i Virgili, Tarragona, Spain
| | - Luis Heredia
- Department of Psychology, Universitat Rovira i Virgili, Tarragona, Spain.,Research Center in Behavioral Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain.,Laboratory of Toxicology and Environmental Health, School of Medicine, Institut d'Investigació Sanitària Pere Virgili (IISPV), Universitat Rovira i Virgili, Tarragona, Spain
| | - Margarita Torrente
- Department of Psychology, Universitat Rovira i Virgili, Tarragona, Spain.,Research Center in Behavioral Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain.,Laboratory of Toxicology and Environmental Health, School of Medicine, Institut d'Investigació Sanitària Pere Virgili (IISPV), Universitat Rovira i Virgili, Tarragona, Spain
| | - José L Domingo
- Laboratory of Toxicology and Environmental Health, School of Medicine, Institut d'Investigació Sanitària Pere Virgili (IISPV), Universitat Rovira i Virgili, Tarragona, Spain
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Abstract
In this review, nonassociative learning is advanced as an organizing principle to draw together findings from both sympathetic-adrenal medullary and hypothalamic-pituitary-adrenocortical (HPA) axis responses to chronic intermittent exposure to a variety of stressors. Studies of habituation, facilitation and sensitization of stress effector systems are reviewed and linked to an animal's prior experience with a given stressor, the intensity of the stressor and the appraisal by the animal of its ability to mobilize physiological systems to adapt to the stressor. Brain pathways that regulate physiological and behavioral responses to stress are discussed, especially in light of their regulation of nonassociative processes in chronic intermittent stress. These findings may have special relevance to various psychiatric diseases, including depression and post-traumatic stress disorder (PTSD).
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Affiliation(s)
- Richard McCarty
- a Department of Psychology , Vanderbilt University , Nashville , TN , USA
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Gouveia MK, Miguel TT, Busnardo C, Scopinho AA, Corrêa FM, Nunes-de-Souza RL, Crestani CC. Dissociation in control of physiological and behavioral responses to emotional stress by cholinergic neurotransmission in the bed nucleus of the stria terminalis in rats. Neuropharmacology 2016; 101:379-88. [DOI: 10.1016/j.neuropharm.2015.10.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 10/03/2015] [Accepted: 10/10/2015] [Indexed: 11/25/2022]
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Moreno Gudiño H, Carías Picón D, de Brugada Sauras I. Dietary choline during periadolescence attenuates cognitive damage caused by neonatal maternal separation in male rats. Nutr Neurosci 2015; 20:327-335. [DOI: 10.1080/1028415x.2015.1126444] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Hayarelis Moreno Gudiño
- Department of Experimental Psychology and Physiology of behavior, University of Granada, Spain
- Department of Biological and Biochemical Processes, Simón Bolívar University, Caracas, Venezuela
| | - Diamela Carías Picón
- Department of Biological and Biochemical Processes, Simón Bolívar University, Caracas, Venezuela
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Paul S, Jeon WK, Bizon JL, Han JS. Interaction of basal forebrain cholinergic neurons with the glucocorticoid system in stress regulation and cognitive impairment. Front Aging Neurosci 2015; 7:43. [PMID: 25883567 PMCID: PMC4382969 DOI: 10.3389/fnagi.2015.00043] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 03/12/2015] [Indexed: 11/28/2022] Open
Abstract
A substantial number of studies on basal forebrain (BF) cholinergic neurons (BFCN) have provided compelling evidence for their role in the etiology of stress, cognitive aging, Alzheimer’s disease (AD), and other neurodegenerative diseases. BFCN project to a broad range of cortical sites and limbic structures, including the hippocampus, and are involved in stress and cognition. In particular, the hippocampus, the primary target tissue of the glucocorticoid stress hormones, is associated with cognitive function in tandem with hypothalamic-pituitary-adrenal (HPA) axis modulation. The present review summarizes glucocorticoid and HPA axis research to date in an effort to establish the manner in which stress affects the release of acetylcholine (ACh), glucocorticoids, and their receptor in the context of cognitive processes. We attempt to provide the molecular interactive link between the glucocorticoids and cholinergic system that contributes to BFCN degeneration in stress-induced acceleration of cognitive decline in aging and AD. We also discuss the importance of animal models in facilitating such studies for pharmacological use, to which could help decipher disease states and propose leads for pharmacological intervention.
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Affiliation(s)
- Saswati Paul
- Department of Biological Sciences, Konkuk University Seoul, South Korea
| | - Won Kyung Jeon
- Herbal Medicine Research Division, Korea Institute of Oriental Medicine Daejeon, South Korea
| | - Jennifer L Bizon
- Department of Neuroscience, College of Medicine, Evelyn F. and William L. McKnight Brain Institute, University of Florida Gainesville, FL, USA
| | - Jung-Soo Han
- Department of Biological Sciences, Konkuk University Seoul, South Korea
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Prenatal corticosterone and adolescent URB597 administration modulate emotionality and CB1 receptor expression in mice. Psychopharmacology (Berl) 2014; 231:2131-44. [PMID: 24311359 DOI: 10.1007/s00213-013-3367-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 11/14/2013] [Indexed: 12/21/2022]
Abstract
RATIONALE The central endocannabinoid system (eCB system) sustains the activity of the hypothalamus-pituitary-adrenal (HPA) axis in mediating individual emotional responses. Deviation in maturational trajectories of these two physiological systems, may persistently adjust individual behavioral phenotype. OBJECTIVE We investigated, in outbred CD1 male mice, whether exposure to prenatal stress may influence short- and long-term emotional and neurochemical responses to a pharmacological stimulation of the eCB system during adolescence. METHODS To mimic prenatal stress, pregnant mice were supplemented with corticosterone in the drinking water (33.3 mg/l); their adolescent male offspring received daily injections of the fatty acid amide hydrolase inhibitor, URB597 (0.4 mg/kg), in order to enhance eCB signaling. Mice were then tested for: locomotor activity during adolescence and locomotor activity, anxiogenic, and anhedonic profiles in adulthood. We analyzed the expression of CB1 receptors (CB1Rs) in prefrontal cortex, hippocampus, striatum, and cerebellum in adulthood. RESULTS Corticosterone administration (PC group) resulted, in adolescence, in a reduction in body weight and locomotion, while in adulthood, in increased anxiety-related behavior and reduced CB1Rs expression in cerebellum. URB597 exposure reduced locomotor activity and increased anhedonia in adulthood. CB1Rs were up-regulated in striatum and hippocampus and down-regulated in the cerebellum. PC-URB597 mice failed to show reductions in locomotion; exhibited increased risk assessment behavior; and showed reduced CB1Rs expression within the prefrontal cortex. CONCLUSIONS Present results provide support to the hypothesis that precocious manipulations mapping onto the HPA axis and eCB system may persistently adjust individual emotional responses and eCB system plasticity.
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Wuwongse S, Cheng SSY, Wong GTH, Hung CHL, Zhang NQ, Ho YS, Law ACK, Chang RCC. Effects of corticosterone and amyloid-beta on proteins essential for synaptic function: implications for depression and Alzheimer's disease. Biochim Biophys Acta Mol Basis Dis 2013; 1832:2245-56. [PMID: 23928361 DOI: 10.1016/j.bbadis.2013.07.022] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 07/02/2013] [Accepted: 07/29/2013] [Indexed: 11/30/2022]
Abstract
The relationship between Alzheimer's disease (AD) and depression has been well established in terms of epidemiological and clinical observations. Depression has been considered to be both a symptom and risk factor of AD. Several genetic and neurobiological mechanisms have been described to underlie these two disorders. Despite the accumulating knowledge on this topic, the precise neuropathological mechanisms remain to be elucidated. In this study, we propose that synaptic degeneration plays an important role in the disease progression of depression and AD. Using primary culture of hippocampal neurons treated with oligomeric Aβ and corticosterone as model agents for AD and depression, respectively, we found significant changes in the pre-synaptic vesicle proteins synaptophysin and synaptotagmin. We further investigated whether the observed protein changes affected synaptic functions. By using FM(®)4-64 fluorescent probe, we showed that synaptic functions were compromised in treated neurons. Our findings led us to investigate the involvement of protein degradation mechanisms in mediating the observed synaptic protein abnormalities, namely, the ubiquitin-proteasome system and autophagy. We found up-regulation of ubiquitin-mediated protein degradation, and the preferential signaling for the autophagic-lysosomal degradation pathway. Lastly, we investigated the neuroprotective role of different classes of antidepressants. Our findings demonstrated that the antidepressants Imipramine and Escitalopram were able to rescue the observed synaptic protein damage. In conclusion, our study shows that synaptic degeneration is an important common denominator underlying depression and AD, and alleviation of this pathology by antidepressants may be therapeutically beneficial.
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Affiliation(s)
- Suthicha Wuwongse
- Neurodysfunction Research Laboratory, Department of Psychiatry, LKS Faculty of Medicine, Hong Kong, China; Laboratory of Neurodegenerative Diseases, Department of Anatomy, LKS Faculty of Medicine, Hong Kong, China
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Sánchez-Resendis O, Medina AC, Serafín N, Prado-Alcalá RA, Roozendaal B, Quirarte GL. Glucocorticoid-cholinergic interactions in the dorsal striatum in memory consolidation of inhibitory avoidance training. Front Behav Neurosci 2012; 6:33. [PMID: 22737110 PMCID: PMC3381328 DOI: 10.3389/fnbeh.2012.00033] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Accepted: 06/08/2012] [Indexed: 11/08/2022] Open
Abstract
Extensive evidence indicates that glucocorticoid hormones act in a variety of brain regions to enhance the consolidation of memory of emotionally motivated training experiences. We previously reported that corticosterone, the major glucocorticoid in the rat, administered into the dorsal striatum immediately after inhibitory avoidance training dose-dependently enhances memory consolidation of this training. There is also abundant evidence that the intrinsic cholinergic system of the dorsal striatum is importantly involved in memory consolidation of inhibitory avoidance training. However, it is presently unknown whether these two neuromodulatory systems interact within the dorsal striatum in the formation of long-term memory. To address this issue, we first investigated in male Wistar rats whether the muscarinic receptor agonist oxotremorine administered into the dorsal striatum immediately after inhibitory avoidance training enhances 48 h retention of the training. Subsequently, we examined whether an attenuation of glucocorticoid signaling by either a systemic administration of the corticosterone-synthesis inhibitor metyrapone or an intra-striatal infusion of the glucocorticoid receptor (GR) antagonist RU 38486 would block the memory enhancement induced by oxotremorine. Our findings indicate that oxotremorine dose-dependently enhanced 48 h retention latencies, but that the administration of either metyrapone or RU 38486 prevented the memory-enhancing effect of oxotremorine. In the last experiment, corticosterone was infused into the dorsal striatum together with the muscarinic receptor antagonist scopolamine immediately after inhibitory avoidance training. Scopolamine blocked the enhancing effect of corticosterone on 48 h retention performance. These findings indicate that there are mutual interactions between glucocorticoids and the striatal cholinergic system in enhancing the consolidation of memory of inhibitory avoidance training.
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Affiliation(s)
- Oscar Sánchez-Resendis
- Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, México
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Increased interactions between PKA and NF-κB signaling in the hippocampus following loss of cholinergic input. Neuroscience 2011; 192:485-93. [PMID: 21723926 DOI: 10.1016/j.neuroscience.2011.05.074] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 05/28/2011] [Accepted: 05/31/2011] [Indexed: 01/06/2023]
Abstract
Neuropsychiatric disorders such as depression are frequently associated with Alzheimer's disease (AD) and the degeneration of cholinergic basal forebrain neurons and reductions in acetylcholine that occur in AD have been identified as potential mediators of these secondary neuropsychiatric symptomologies. Indeed, removal of cholinergic innervation to the hippocampus via selective immunolesions of septohippocampal cholinergic neurons induces dysfunction of the hypothalamic-pituitary-adrenocortical (HPA) axis and decreases glucocorticoid receptor expression (GR). A subsequent study showed that loss of cholinergic input decreases the activity of the catalytic subunit of protein kinase A (PKAc) and lessens the interaction of protein kinase A (PKA) with GR. Because cross-coupling between nuclear factor-κB (NF-κB) p65 and GR depends on PKA signaling, the present study was conducted to evaluate the status of NF-κB as well as interactions of PKA with NF-κB in the hippocampus following cholinergic denervation. Expression of cytosolic NF-κB p65 was diminished and IκB was degraded in the hippocampus of cholinergic immunolesioned rats compared to the controls. Immunolesions also increased NF-κB p65 Ser276 phosphorylation, as well as interactions between PKAc and NF-κB p65. These results indicate that loss of cholinergic input to the hippocampus results in decreased PKA activity and increased NF-κB activity. Such altered signaling may contribute to psychiatric symptoms, including depression, in patients with AD.
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Decreased interactions in protein kinase A-Glucocorticoid receptor signaling in the hippocampus after selective removal of the basal forebrain cholinergic input. Hippocampus 2011; 22:455-65. [DOI: 10.1002/hipo.20912] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2010] [Indexed: 01/05/2023]
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Localization of pre- and postsynaptic cholinergic markers in rodent forebrain: a brief history and comparison of rat and mouse. Behav Brain Res 2010; 221:356-66. [PMID: 21129407 DOI: 10.1016/j.bbr.2010.11.051] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Accepted: 11/23/2010] [Indexed: 11/23/2022]
Abstract
Rat and mouse models are widely used for studies in cognition and pathophysiology, among others. Here, we sought to determine to what extent these two model species differ for cholinergic and cholinoceptive features. For this purpose, we focused on cholinergic innervation patterns based on choline acetyltransferase (ChAT) immunostaining, and the expression of muscarinic acetylcholine receptors (mAChRs) detected immunocytochemically. In this brief review we first place cholinergic and cholinoceptive markers in a historic perspective, and then provide an overview of recent publications on cholinergic studies and techniques to provide a literature survey of current research. Next, we compare mouse (C57Bl/J6) and rat (Wistar) cholinergic and cholinoceptive systems simultaneously stained, respectively, for ChAT (analyzed qualitatively) and mAChRs (analyzed qualitatively and quantitatively). In general, the topographic cholinergic innervation patterns of both rodent species are highly comparable, with only considerable (but region specific) differences in number of detectable cholinergic interneurons, which are more numerous in rat. In contrast, immunolabeling for mAChRs, detected by the monoclonal antibody M35, differs markedly in the forebrain between the two species. In mouse brain, basal levels of activated and/or internalized mAChRs (as a consequence of cholinergic neurotransmission) are significantly higher. This suggests a higher cholinergic tone in mouse than rat, and hence the animal model of choice may have consequences for cholinergic drug testing experiments.
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Aisa B, Gil-Bea FJ, Marcos B, Tordera R, Lasheras B, Del Río J, Ramírez MJ. Neonatal stress affects vulnerability of cholinergic neurons and cognition in the rat: involvement of the HPA axis. Psychoneuroendocrinology 2009; 34:1495-505. [PMID: 19505767 DOI: 10.1016/j.psyneuen.2009.05.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 04/03/2009] [Accepted: 05/07/2009] [Indexed: 11/15/2022]
Abstract
Adverse experiences early in life may sensitize specific neurocircuits to subsequent stressors. We have evaluated in maternal separation (MS) rats, an animal paradigm of early-life stress, the effects of a selective cholinergic lesion on cognitive function as well as susceptibility of cholinergic neurons to the lesion. MS rats subjected to a cholinergic lesion by administration of the immunotoxin 192 IgG-saporin, showed significant decreases in both choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activity compared to control lesioned rats. Morris water maze results revealed a significant impairment in learning and memory function in MS adult rats and further cognitive deficits after the lesion. The lesion of cholinergic neurons induced a significant decrease in glucocorticoid receptor density in MS rats, accompanied by increases in CRF mRNA expression. Decreases in NGF and increases in NGF-p75NTR expression have also been found in MS rats. Our results suggest that vulnerability of basal forebrain cholinergic nerve cells might be affected by the HPA axis. The present data are discussed not only in terms of conditions that occur during ageing or Alzheimer disease, but also regarding a purported involvement of the cholinergic system in the regulation of HPA axis activity.
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Affiliation(s)
- Bárbara Aisa
- Department of Pharmacology, School of Medicine, University of Navarra, Irunlarrea 1, 31008 Pamplona, Spain
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The interaction between acute oligomer Abeta(1-40) and stress severely impaired spatial learning and memory. Neurobiol Learn Mem 2009; 93:8-18. [PMID: 19660564 DOI: 10.1016/j.nlm.2009.07.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Revised: 07/24/2009] [Accepted: 07/29/2009] [Indexed: 11/24/2022]
Abstract
In this study, we investigated whether stress can enhance the toxicity of oligomer Abeta(1-40) in the mouse brain. Stress was applied to the animals, consisting of a 2-day inescapable foot shock followed by 3-weekly situation reminders (SRs). We found that stress significantly affected not only the amygdala-dependent (anxiety) but also the hippocampal-dependent (spatial learning and memory) behaviors through the oxidative damage caused in these two regions. However, oligomer Abeta(1-40) treatment alone did not induce behavioral impairment. In addition, combined oligomer Abeta(1-40) and stress treatment increased the glucocorticoid receptor (GR)/mineralocorticoid receptor (MR) ratio and the expression of corticotrophin releasing factor 1 (CRF-1) receptor in the hippocampus. Changes in the components of the hypothalamic-pituitary-adrenal (HPA) axis, such as the GR/MR ratio and CRF-1 level, were observed, accompanied by increasing Abeta accumulation, oxidative stress, nuclear transcription factor (NF-kappaB) hypoactivity, and apoptotic signaling in the hippocampus, and decreasing calbindin D28K and NMDA receptor 2A/2B (NR2A/2B) in the hippocampus, along with alteration of the cholinergic neurons (ChAT) in the medium septum/diagnoid band (MS/DB), noradrenergic neurons (TH) in the locus coeruleus (LC), and serotonergic neurons (5-HT) in the Raphe nucleus. Therefore, apoptosis and synaptic dysfunction in the hippocampus severely induced the impairment of spatial learning and memory. These results suggest that stress may play an important role in the early stages of Alzheimer's disease (AD), and an antioxidant strategy might be a potential therapeutic approach for stress-mediated disorders.
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Craig LA, Hong NS, Kopp J, McDonald RJ. Emergence of spatial impairment in rats following specific cholinergic depletion of the medial septum combined with chronic stress. Eur J Neurosci 2008; 27:2262-71. [DOI: 10.1111/j.1460-9568.2008.06179.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Pondiki S, Stamatakis A, Fragkouli A, Philippidis H, Stylianopoulou F. Effects of neonatal handling on the basal forebrain cholinergic system of adult male and female rats. Neuroscience 2006; 142:305-14. [PMID: 16905266 DOI: 10.1016/j.neuroscience.2006.06.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Revised: 06/14/2006] [Accepted: 06/14/2006] [Indexed: 10/24/2022]
Abstract
Neonatal handling is an early experience which results in improved function of the hypothalamic-pituitary-adrenal axis, increased adaptability and coping as a response to stress, as well as better cognitive abilities. In the present study, we investigated the effect of neonatal handling on the basal forebrain cholinergic system, since this system is known to play an important role in cognitive processes. We report that neonatal handling results in increased number of choline-acetyl transferase immunopositive cells in the septum/diagonal band, in both sexes, while no such effect was observed in the other cholinergic nuclei, such as the magnocellular preoptic nucleus and the nucleus basalis of Meynert. In addition, neonatal handling resulted in increased M1 and M2 muscarinic receptor binding sites in the cingulate and piriform cortex of both male and female rats. A handling-induced increase in M1 muscarinic receptor binding sites was also observed in the CA3 and CA4 (fields 3 and 4 of Ammon's horn) areas of the hippocampus. Furthermore, a handling-induced increase in acetylcholinesterase staining was found only in the hippocampus of females. Our results thus show that neonatal handling acts in a sexually dimorphic manner on one of the cholinergic parameters, and has a beneficial effect on BFCS function, which could be related to the more efficient and adaptive stress response and the superior cognitive abilities of handled animals.
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Affiliation(s)
- S Pondiki
- Laboratory of Biology-Biochemistry, Faculty of Nursing, School of Health Sciences, University of Athens, Athens, Greece
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