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Kouhnavardi S, Cabatic M, Mañas-Padilla MC, Malabanan MA, Smani T, Cicvaric A, Muñoz Aranzalez EA, Koenig X, Urban E, Lubec G, Castilla-Ortega E, Monje FJ. miRNA-132/212 Deficiency Disrupts Selective Corticosterone Modulation of Dorsal vs. Ventral Hippocampal Metaplasticity. Int J Mol Sci 2023; 24:9565. [PMID: 37298523 PMCID: PMC10253409 DOI: 10.3390/ijms24119565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/21/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
Cortisol is a potent human steroid hormone that plays key roles in the central nervous system, influencing processes such as brain neuronal synaptic plasticity and regulating the expression of emotional and behavioral responses. The relevance of cortisol stands out in the disease, as its dysregulation is associated with debilitating conditions such as Alzheimer's Disease, chronic stress, anxiety and depression. Among other brain regions, cortisol importantly influences the function of the hippocampus, a structure central for memory and emotional information processing. The mechanisms fine-tuning the different synaptic responses of the hippocampus to steroid hormone signaling remain, however, poorly understood. Using ex vivo electrophysiology and wild type (WT) and miR-132/miR-212 microRNAs knockout (miRNA-132/212-/-) mice, we examined the effects of corticosterone (the rodent's equivalent to cortisol in humans) on the synaptic properties of the dorsal and ventral hippocampus. In WT mice, corticosterone predominantly inhibited metaplasticity in the dorsal WT hippocampi, whereas it significantly dysregulated both synaptic transmission and metaplasticity at dorsal and ventral regions of miR-132/212-/- hippocampi. Western blotting further revealed significantly augmented levels of endogenous CREB and a significant CREB reduction in response to corticosterone only in miR-132/212-/- hippocampi. Sirt1 levels were also endogenously enhanced in the miR-132/212-/- hippocampi but unaltered by corticosterone, whereas the levels of phospo-MSK1 were only reduced by corticosterone in WT, not in miR-132/212-/- hippocampi. In behavioral studies using the elevated plus maze, miRNA-132/212-/- mice further showed reduced anxiety-like behavior. These observations propose miRNA-132/212 as potential region-selective regulators of the effects of steroid hormones on hippocampal functions, thus likely fine-tuning hippocampus-dependent memory and emotional processing.
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Affiliation(s)
- Shima Kouhnavardi
- Center for Physiology and Pharmacology, Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Maureen Cabatic
- Center for Physiology and Pharmacology, Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | | | - Marife-Astrid Malabanan
- Center for Physiology and Pharmacology, Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Tarik Smani
- Department of Medical Physiology and Biophysics, University of Seville, 41013 Seville, Spain
| | - Ana Cicvaric
- Center for Physiology and Pharmacology, Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Edison Alejandro Muñoz Aranzalez
- Center for Physiology and Pharmacology, Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Xaver Koenig
- Center for Physiology and Pharmacology, Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Ernst Urban
- Department for Pharmaceutical Sciences, Josef-Holaubek-Platz 2, 2D 303, 1090 Vienna, Austria
| | - Gert Lubec
- Programme for Proteomics, Paracelsus Medical University, 5020 Salzburg, Austria
| | | | - Francisco J. Monje
- Center for Physiology and Pharmacology, Department of Neurophysiology and Neuropharmacology, Medical University of Vienna, 1090 Vienna, Austria
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2
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Zhu H, Cong L, Chen Y, Chen S, Chen L, Huang Z, Zhou J, Xiao J, Huang Y, Su D. Efficiency of donepezil in elderly patients undergoing orthopaedic surgery due to underlying post-operative cognitive dysfunction: study protocol for a multicentre randomised controlled trial. Trials 2021; 22:688. [PMID: 34627332 PMCID: PMC8501596 DOI: 10.1186/s13063-021-05648-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 09/20/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Post-operative cognitive dysfunction (POCD) is an overarching term used to describe cognitive impairment identified in the preoperative or post-operative period. After surgical operations, older patients are particularly vulnerable to memory disturbances and other types of cognitive impairment. However, the pathogenesis of POCD remains unclear with no confirmed preventable or treatable strategy available. Our previous study demonstrated that the concentration of choline acetyl transferase in the cerebral spinal fluid was a predictive factor of POCD and that donepezil, which is an acetylcholinesterase inhibitor used in clinical settings for the treatment of Alzheimer's disease, can prevent learning and memory impairment after anaesthesia/surgery in aged mice. This study aimed to determine the critical role of donepezil in preventing cognitive impairment in elderly patients undergoing orthopaedic surgery. METHODS A multicentre, double-blind, placebo-controlled, crossover clinical trial will be performed to assess the efficacy of donepezil in elderly patients undergoing orthopaedic surgery. Participants (n = 360) will receive donepezil (5 mg once daily) or placebo from 1 day prior to surgery until 5 days after surgery. Neuropsychological tests will be measured at 1 day before the operation and 1 week, 1 month, 6 months and 1 year after the operation. DISCUSSION This research project mainly aimed to study the effects of donepezil in elderly patients undergoing orthopaedic surgery due to underlying POCD and to investigate the underlying physiological and neurobiological mechanisms of these effects. The results may provide important implications for the development of effective interfering strategies, specifically regarding cognitive dysfunction therapy using drugs. TRIAL REGISTRATION ClinicalTrials.gov NCT04423276 . Registered on 14 June 2020.
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Affiliation(s)
- Huichen Zhu
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China
| | - Lu Cong
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China
| | - Yi Chen
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China
| | - Shaoyi Chen
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China
| | - Lingke Chen
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China
| | - Zhenling Huang
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China
| | - Jie Zhou
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China
| | - Jie Xiao
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China
| | - Yonglei Huang
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China.
| | - Diansan Su
- Department of Anesthesiology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, 160 Pujian Road, Shanghai, 200127, China.
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3
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Wang Y, Wang Q, Chen J, Yao LH, Tang N, Jiang ZX, Luo Y. Protective Effect of Hydroxysafflor Yellow A against Chronic Mild Stress-induced Memory Impairments by Suppressing Tau Phosphorylation in Mice. Curr Med Sci 2021; 41:555-564. [PMID: 34129201 DOI: 10.1007/s11596-021-2369-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 09/10/2020] [Indexed: 12/19/2022]
Abstract
Chronic stress plays a critical role in the etiology of sporadic Alzheimer's disease (AD). However, there are currently no effective drugs that can target chronic stress to prevent AD. In this study, we explored the neuroprotective effect of hydroxysafflor yellow A (HSYA) against chronic mild stress (CMS)-induced memory impairments in mice and the underlying mechanism. The Morris water maze test showed that HSYA significantly reduced CMS-induced learning and memory impairments in mice. HSYA increased the expression of brain-derived neurotrophic factor (BDNF) and activated downstream tropomyosin-related kinase B (TrkB) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B(Akt)/mammalian target of rapamycin (mTOR) signaling. HSYA decreased the expression of regulator of calcineurin 1-1L (RCAN1-1L) that could promote the activity of glycogen synthase kinase-3β (GSK-3β). HSYA also attenuated tau phosphorylation by inhibiting the activity of GSK-3β and cyclin-dependent kinase-5 (Cdk5). Our data indicated that HSYA has protective effects against CMS-induced BDNF downregulation, tau phosphorylation and memory impairments. HSYA may be a promising therapeutic candidate for AD by targeting chronic stress.
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Affiliation(s)
- Ying Wang
- Department of Neurology, The First Hospital of Lanzhou University, Lanzhou, 730000, China
| | - Qiang Wang
- Department of Neurology, The First Hospital of Lanzhou University, Lanzhou, 730000, China
| | - Jun Chen
- Department of Neurology, The First Hospital of Lanzhou University, Lanzhou, 730000, China
| | - Li-He Yao
- Department of Neurology, The First Hospital of Lanzhou University, Lanzhou, 730000, China
| | - Ni Tang
- Department of Neurology, The First Hospital of Lanzhou University, Lanzhou, 730000, China
| | - Zhen-Xiu Jiang
- Department of Neurology, The First Hospital of Lanzhou University, Lanzhou, 730000, China
| | - Yu Luo
- Institute of Pathophysiology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China.
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4
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The Calcium/Calmodulin-Dependent Kinases II and IV as Therapeutic Targets in Neurodegenerative and Neuropsychiatric Disorders. Int J Mol Sci 2021; 22:ijms22094307. [PMID: 33919163 PMCID: PMC8122486 DOI: 10.3390/ijms22094307] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/13/2021] [Accepted: 04/17/2021] [Indexed: 12/14/2022] Open
Abstract
CaMKII and CaMKIV are calcium/calmodulin-dependent kinases playing a rudimentary role in many regulatory processes in the organism. These kinases attract increasing interest due to their involvement primarily in memory and plasticity and various cellular functions. Although CaMKII and CaMKIV are mostly recognized as the important cogs in a memory machine, little is known about their effect on mood and role in neuropsychiatric diseases etiology. Here, we aimed to review the structure and functions of CaMKII and CaMKIV, as well as how these kinases modulate the animals’ behavior to promote antidepressant-like, anxiolytic-like, and procognitive effects. The review will help in the understanding of the roles of the above kinases in the selected neurodegenerative and neuropsychiatric disorders, and this knowledge can be used in future drug design.
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5
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GABA-A receptor modulating steroids in acute and chronic stress; relevance for cognition and dementia? Neurobiol Stress 2019; 12:100206. [PMID: 31921942 PMCID: PMC6948369 DOI: 10.1016/j.ynstr.2019.100206] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/13/2019] [Accepted: 12/18/2019] [Indexed: 01/10/2023] Open
Abstract
Cognitive dysfunction, dementia and Alzheimer's disease (AD) are increasing as the population worldwide ages. Therapeutics for these conditions is an unmet need. This review focuses on the role of the positive GABA-A receptor modulating steroid allopregnanolone (APα), it's role in underlying mechanisms for impaired cognition and of AD, and to determine options for therapy of AD. On one hand, APα given intermittently promotes neurogenesis, decreases AD-related pathology and improves cognition. On the other, continuous exposure of APα impairs cognition and deteriorates AD pathology. The disparity between these two outcomes led our groups to analyze the mechanisms underlying the difference. We conclude that the effects of APα depend on administration pattern and that chronic slightly increased APα exposure is harmful to cognitive function and worsens AD pathology whereas single administrations with longer intervals improve cognition and decrease AD pathology. These collaborative assessments provide insights for the therapeutic development of APα and APα antagonists for AD and provide a model for cross laboratory collaborations aimed at generating translatable data for human clinical trials.
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6
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Alkadhi KA. Neuroprotective Effects of Nicotine on Hippocampal Long-Term Potentiation in Brain Disorders. J Pharmacol Exp Ther 2018; 366:498-508. [DOI: 10.1124/jpet.118.247841] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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7
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Alkadhi KA. Delayed effects of combined stress and Aβ infusion on L-LTP of the dentate gyrus: Prevention by nicotine. Neurosci Lett 2018; 682:10-15. [PMID: 29883681 DOI: 10.1016/j.neulet.2018.05.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 05/15/2018] [Accepted: 05/25/2018] [Indexed: 11/16/2022]
Abstract
Alzheimer's Disease (AD) is a progressive dementia hallmarked by the presence in the brain of extracellular beta-amyloid (Aβ) plaques and intraneuronal fibrillary tangles. Chronic stress is associated with heightened Aβ buildup and acceleration of development of AD, however, stress alone has no significant effect on synaptic plasticity in the dentate gyrus (DG) area. Previously, we have reported that the combination of stress and AD causes more severe inhibition of synaptic plasticity of hippocampal area CA1 than chronic stress or AD alone, and that chronic nicotine treatment prevents this impairment. To investigate the effect of stress and nicotine on synaptic plasticity in the relatively injury-resistant DG area, the present experiments analyzed the effect of chronic stress and the neuroprotective effect of nicotine on LTP in the DG area of a rat model of AD. Wistar rats were chronically stressed and treated with nicotine (1 mg/kg/twice daily; s.c.) for six weeks. Then, at weeks 5-6, AD model was generated by 14-day i.c.v osmotic pump infusion of Aβ peptides (300 pmol/day) into the brains of these rats. Field potential recordings from the DG area of anesthetized rats, revealed that while chronic stress did not accentuate Aβ-induced impairments of E-LTP, it markedly augmented Aβ effect on L-LTP that was only seen 100 min after multiple high frequency stimulation. This delayed action is likely to be due to impairment of process of de novo protein synthesis required for maintenance phase of L-LTP. Chronic nicotine treatment prevented stress-enhanced suppression of synaptic plasticity.
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Affiliation(s)
- Karim A Alkadhi
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, 77204, USA.
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8
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Esteves I, Lopes-Aguiar C, Rossignoli M, Ruggiero R, Broggini A, Bueno-Junior L, Kandratavicius L, Monteiro M, Romcy-Pereira R, Leite J. Chronic nicotine attenuates behavioral and synaptic plasticity impairments in a streptozotocin model of Alzheimer’s disease. Neuroscience 2017; 353:87-97. [DOI: 10.1016/j.neuroscience.2017.04.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/04/2017] [Accepted: 04/10/2017] [Indexed: 01/23/2023]
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9
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Mahdavi S, Khodarahmi P, Roodbari NH. Effects of cadmium on Bcl-2/Bax expression ratio in rat cortex brain and hippocampus. Hum Exp Toxicol 2017; 37:321-328. [DOI: 10.1177/0960327117703687] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
To investigate the underlying mechanism of neurotoxicity of cadmium, we examined the effects of intraperitoneal injection of cadmium on messenger RNA (mRNA) expression of Bcl-2 (B-cell lymphoma 2) and Bax (Bcl2-associated x) genes and caspase-3/7 activation in rat hippocampus and frontal cortex. Twenty-eight male Wistar rats weighing 200–250 g were randomly divided into four groups. Control group received saline and three other groups received cadmium at doses of 1, 2 and 4 mg/kg (body weight) for 15 successive days. One day after the last injection, the hippocampus and frontal cortex were dissected and removed and then the expression of Bcl-2 and Bax genes was evaluated using real-time polymerase chain reaction and apoptotic studies was done using caspase-3/7 activation assay. Cadmium reduced the mRNA level of Bcl-2 in the control group at doses of 1 ( p < 0.01), 2 and 4 mg/kg ( p < 0.001) in rat hippocampus and cortex cells. The mRNA level of Bax increased significantly compared to the control group at the doses of 1 ( p < 0.05), 2 and 4 mg/kg ( p < 0.001) in rat hippocampus. The mRNA level of Bax was increased significantly compared to the control group at the doses of 2 and 4 mg/kg ( p < 0.001) in rat cortex cells. Cadmium increased caspase-3/7 activity at doses of 1, 2 and 4 mg/kg in rat hippocampus. Caspase-3/7 activity was increased significantly at dose of 4 mg/kg in rat cortex. This decreased Bcl-2/Bax mRNA ratio induces cell apoptosis. Apoptotic effect of cadmium may be through the mitochondrial pathway by the activation of caspase-3/7.
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Affiliation(s)
- S Mahdavi
- Department of Biology, Parand Branch, Islamic Azad University, Parand, Iran
| | - P Khodarahmi
- Department of Biology, Parand Branch, Islamic Azad University, Parand, Iran
| | - NH Roodbari
- Department of Biology, Sciences and Research Branch, Islamic Azad University, Tehran, Iran
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10
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Echeverria V, Yarkov A, Aliev G. Positive modulators of the α7 nicotinic receptor against neuroinflammation and cognitive impairment in Alzheimer's disease. Prog Neurobiol 2016; 144:142-57. [DOI: 10.1016/j.pneurobio.2016.01.002] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 11/07/2015] [Accepted: 01/06/2016] [Indexed: 01/08/2023]
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11
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Lee B, Sur B, Cho SG, Yeom M, Shim I, Lee H, Hahm DH. Effect of Beta-Asarone on Impairment of Spatial Working Memory and Apoptosis in the Hippocampus of Rats Exposed to Chronic Corticosterone Administration. Biomol Ther (Seoul) 2015; 23:571-81. [PMID: 26535083 PMCID: PMC4624074 DOI: 10.4062/biomolther.2015.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 08/11/2015] [Accepted: 08/12/2015] [Indexed: 02/02/2023] Open
Abstract
β-asarone (BAS) is an active component of Acori graminei rhizoma, a traditional medicine used clinically in treating dementia and chronic stress in Korea. However, the cognitive effects of BAS and its mechanism of action have remained elusive. The purpose of this study was to examine whether BAS improved spatial cognitive impairment induced in rats following chronic corticosterone (CORT) administration. CORT administration (40 mg/kg, i.p., 21 days) resulted in cognitive impairment in the avoidance conditioning test (AAT) and the Morris water maze (MWM) test that was reversed by BAS (200 mg/kg, i.p). Additionally, as assessed by immunohistochemistry and RT-PCR analysis, the administration of BAS significantly alleviated memory-associated decreases in the expression levels of brain-derived neurotrophic factor (BDNF) and cAMP-response element-binding protein (CREB) proteins and mRNAs in the hippocampus. Also, BAS administration significantly restored the expression of Bax and Bcl-2 mRNAs in the hippocampus. Thus, BAS may be an effective therapeutic for learning and memory disturbances, and its neuroprotective effect was mediated, in part, by normalizing the CORT response, resulting in regulation of BDNF and CREB functions and anti-apoptosis in rats.
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Affiliation(s)
- Bombi Lee
- Acupuncture and Meridian Science Research Center, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
| | - Bongjun Sur
- Acupuncture and Meridian Science Research Center, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
| | - Seong-Guk Cho
- The Graduate School of Basic Science of Korean Medicine, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
| | - Mijung Yeom
- Acupuncture and Meridian Science Research Center, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
| | - Insop Shim
- Acupuncture and Meridian Science Research Center, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
- The Graduate School of Basic Science of Korean Medicine, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
| | - Hyejung Lee
- Acupuncture and Meridian Science Research Center, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
- The Graduate School of Basic Science of Korean Medicine, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
| | - Dae-Hyun Hahm
- Acupuncture and Meridian Science Research Center, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
- The Graduate School of Basic Science of Korean Medicine, College of Korean Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea
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Korpi ER, den Hollander B, Farooq U, Vashchinkina E, Rajkumar R, Nutt DJ, Hyytiä P, Dawe GS. Mechanisms of Action and Persistent Neuroplasticity by Drugs of Abuse. Pharmacol Rev 2015; 67:872-1004. [DOI: 10.1124/pr.115.010967] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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13
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Zagaar MA, Dao AT, Alhaider IA, Alkadhi KA. Prevention by Regular Exercise of Acute Sleep Deprivation-Induced Impairment of Late Phase LTP and Related Signaling Molecules in the Dentate Gyrus. Mol Neurobiol 2015; 53:2900-2910. [PMID: 25902862 DOI: 10.1007/s12035-015-9176-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 04/13/2015] [Indexed: 01/12/2023]
Abstract
The dentate gyrus (DG) and CA1 regions of the hippocampus are intimately related physically and functionally, yet they react differently to insults. The purpose of this study was to determine the protective effects of regular treadmill exercise on late phase long-term potentiation (L-LTP) and its signaling cascade in the DG region of the hippocampus of rapid eye movement (REM) sleep-deprived rats. Adult Wistar rats ran on treadmills for 4 weeks then were acutely sleep deprived for 24 h using the modified multiple platform method. After sleep deprivation, the rats were anesthetized and L-LTP was induced in the DG region. Extracellular field potentials from the DG were recorded in vivo, and levels of L-LTP-related signaling proteins were assessed both before and after L-LTP expression using immunoblot analysis. Sleep deprivation reduced the basal levels of phosphorylated cAMP response element-binding protein (P-CREB) as well as other upstream modulators including calcium/calmodulin kinase IV (CaMKIV) and brain-derived neurotrophic factor (BDNF) in the DG of the hippocampus. Regular exercise prevented impairment of the basal levels of P-CREB and total CREB as well as those of CaMKIV in sleep-deprived animals. Furthermore, regular exercise prevented sleep deprivation-induced inhibition of L-LTP and post-L-LTP downregulation of P-CREB and BDNF levels in the DG. The current findings show that our exercise regimen prevents sleep deprivation-induced deficits in L-LTP as well as the basal and poststimulation levels of key signaling molecules.
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Affiliation(s)
- Munder A Zagaar
- Departmentof Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, TX, USA
| | - An T Dao
- Departmentof Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, TX, USA
| | - Ibrahim A Alhaider
- College of Clinical Pharmacy, King Faisal University, Al-Hofuf, Saudi Arabia
| | - Karim A Alkadhi
- Departmentof Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, TX, USA.
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14
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Xue M, Zhu L, Zhang J, Qiu J, Du G, Qiao Z, Jin G, Gao F, Zhang Q. Low dose nicotine attenuates Aβ neurotoxicity through activation early growth response gene 1 pathway. PLoS One 2015; 10:e0120267. [PMID: 25815723 PMCID: PMC4376385 DOI: 10.1371/journal.pone.0120267] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 01/21/2015] [Indexed: 02/06/2023] Open
Abstract
Epidemiological studies indicate that smoking is negatively correlated with the incidence and development of Alzheimer's disease (AD). Nicotine was reported to be the active factor. However, the detailed mechanisms still remain to be fully elucidated. Early growth response gene 1 (EGR-1) plays important roles in several important biological processes such as promoting cell growth, differentiation, anti oxidative stress, and apoptosis, but few in the pathogenesis of AD. In the present study, we show that nicotine can activate the MAPK/ERK/EGR-1 signaling pathway partially through α7 nAChR. In addition, the up-regulation of EGR-1 by nicotine can also increase the phosphorylation of CyclinD1 which contributes to the attenuation of amyloid-β (Aβ(25-35)) -induced neurotoxicity. Although nicotine and Aβ(25-35) can activate EGR-1, the expression of EGR-1 is down-regulated following treatment with nicotine and Aβ(25-35). This study demonstrates that low dose nicotine attenuates Aβ(25-35)-induced neurotoxicity in vitro and in vivo through activating EGR-1 pathway.
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Affiliation(s)
- Maoqiang Xue
- College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, P.R.China
- Institute of Biomedical Engineering, Department of Biomaterials, College of Materials, Xiamen University, Xiamen, Fujian, 361005, P.R.China
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian, 361005, P.R.China
| | - Liuwei Zhu
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian, 361005, P.R.China
| | - Jie Zhang
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian, 361005, P.R.China
| | - Jinhua Qiu
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian, 361005, P.R.China
| | - Guicheng Du
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian, 361005, P.R.China
| | - Zhiliang Qiao
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian, 361005, P.R.China
| | - Guanghui Jin
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian, 361005, P.R.China
| | - Fengguang Gao
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian, 361005, P.R.China
| | - Qiqing Zhang
- College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian, 361005, P.R.China
- Institute of Biomedical Engineering, Department of Biomaterials, College of Materials, Xiamen University, Xiamen, Fujian, 361005, P.R.China
- Institute of Biomedical Engineering, Chinese Academy of Medical Science & Peking Union Medical College, The Key Laboratory of Biomedical Material of Tianjin, Tianjin, 300192, P.R.China
- * E-mail:
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15
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Philpot RM. Potential Use of Nicotinic Receptor Agonists for the Treatment of Chemotherapy-Induced Cognitive Deficits. Neurochem Res 2015; 40:2018-31. [DOI: 10.1007/s11064-015-1528-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 01/09/2015] [Accepted: 01/28/2015] [Indexed: 10/24/2022]
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Little CS, Joyce TA, Hammond CJ, Matta H, Cahn D, Appelt DM, Balin BJ. Detection of bacterial antigens and Alzheimer's disease-like pathology in the central nervous system of BALB/c mice following intranasal infection with a laboratory isolate of Chlamydia pneumoniae. Front Aging Neurosci 2014; 6:304. [PMID: 25538615 PMCID: PMC4257355 DOI: 10.3389/fnagi.2014.00304] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 10/18/2014] [Indexed: 12/28/2022] Open
Abstract
Pathology consistent with that observed in Alzheimer's disease (AD) has previously been documented following intranasal infection of normal wild-type mice with Chlamydia pneumoniae (Cpn) isolated from an AD brain (96-41). In the current study, BALB/c mice were intranasally infected with a laboratory strain of Cpn, AR-39, and brain and olfactory bulbs were obtained at 1-4 months post-infection (pi). Immunohistochemistry for amyloid beta or Cpn antigens was performed on sections from brains of infected or mock-infected mice. Chlamydia-specific immunolabeling was identified in olfactory bulb tissues and in cerebrum of AR-39 infected mice. The Cpn specific labeling was most prominent at 1 month pi and the greatest burden of amyloid deposition was noted at 2 months pi, whereas both decreased at 3 and 4 months. Viable Cpn was recovered from olfactory bulbs of 3 of 3 experimentally infected mice at 1 and 3 months pi, and in 2 of 3 mice at 4 months pi. In contrast, in cortical tissues of infected mice at 1 and 4 months pi no viable organism was obtained. At 3 months pi, only 1 of 3 mice had a measurable burden of viable Cpn from the cortical tissues. Mock-infected mice (0 of 3) had no detectable Cpn in either olfactory bulbs or cortical tissues. These data indicate that the AR-39 isolate of Cpn establishes a limited infection predominantly in the olfactory bulbs of BALB/c mice. Although infection with the laboratory strain of Cpn promotes deposition of amyloid beta, this appears to resolve following reduction of the Cpn antigen burden over time. Our data suggest that infection with the AR-39 laboratory isolate of Cpn results in a different course of amyloid beta deposition and ultimate resolution than that observed following infection with the human AD-brain Cpn isolate, 96-41. These data further support that there may be differences, possibly in virulence factors, between Cpn isolates in the generation of sustainable AD pathology.
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Affiliation(s)
- Christopher S. Little
- Department of Bio-Medical Sciences, Philadelphia College of Osteopathic MedicinePhiladelphia, PA USA
- Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic MedicinePhiladelphia, PA, USA
| | - Timothy A. Joyce
- Department of Bio-Medical Sciences, Philadelphia College of Osteopathic MedicinePhiladelphia, PA USA
- Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic MedicinePhiladelphia, PA, USA
| | - Christine J. Hammond
- Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic MedicinePhiladelphia, PA, USA
- Division of Research, Philadelphia College of Osteopathic MedicinePhiladelphia, PA, USA
| | - Hazem Matta
- Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic MedicinePhiladelphia, PA, USA
| | - David Cahn
- Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic MedicinePhiladelphia, PA, USA
| | - Denah M. Appelt
- Department of Bio-Medical Sciences, Philadelphia College of Osteopathic MedicinePhiladelphia, PA USA
- Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic MedicinePhiladelphia, PA, USA
| | - Brian J. Balin
- Department of Bio-Medical Sciences, Philadelphia College of Osteopathic MedicinePhiladelphia, PA USA
- Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic MedicinePhiladelphia, PA, USA
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Alkadhi KA, Tran TT. Chronic Stress Decreases Basal Levels of Memory-Related Signaling Molecules in Area CA1 of At-Risk (Subclinical) Model of Alzheimer’s Disease. Mol Neurobiol 2014; 52:93-100. [DOI: 10.1007/s12035-014-8839-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 07/30/2014] [Indexed: 11/28/2022]
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Dao AT, Zagaar MA, Levine AT, Salim S, Eriksen JL, Alkadhi KA. Treadmill exercise prevents learning and memory impairment in Alzheimer's disease-like pathology. Curr Alzheimer Res 2014; 10:507-15. [PMID: 23627709 DOI: 10.2174/1567205011310050006] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 01/29/2013] [Accepted: 01/30/2013] [Indexed: 12/29/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder that is characterized by progressive memory loss. In contrast, accumulating evidence suggests a neuroprotective role of regular exercise in aging associated memory impairment. In this study, we investigated the ability of regular exercise to prevent impairments of short-term memory (STM) and early long-term potentiation (E-LTP) in area CA1 of the hippocampus in a rat model of AD (i.c.v. infusion of 250 pmol/day Aβ1-42 peptides). We utilized behavioral assessment, in vivo electrophysiological recording, and immunoblotting in 4 groups of adult Wistar rats: control, treadmill exercise (Ex), β-amyloid-infused (Aβ), and amyloid-infused/treadmill exercised (Ex/Aβ). Our findings indicated that Aβ rats made significantly more errors in the radial arm water maze (RAWM) compared to all other groups and exhibited suppressed E-LTP in area CA1, which correlated with deleterious alterations in the levels of memory and E-LTP-related signaling molecules including calcineurin (PP2B), brain derivedneurotrophic factor (BDNF) and phosphorylated CaMKII (p-CaMKII). Compared to controls, Ex and Ex/Aβ rats showed a similar behavioral performance and a normal E-LTP with no detrimental changes in the levels of PP2B, BDNF, and p- CaMKII. We conclude that treadmill exercise maybe able to prevent cognitive impairment associated with AD pathology.
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Affiliation(s)
- An T Dao
- Department of PPS, College of Pharmacy, University of Houston, Houston, TX 77204-5037, USA
| | - Munder A Zagaar
- Texas Southern University Department of Pharmacy Practice and Clinical Health Sciences Houston, TX 77004
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Abstract
Exposure to various forms of stress is a common daily occurrence in the lives of most individuals, with both positive and negative effects on brain function. The impact of stress is strongly influenced by the type and duration of the stressor. In its acute form, stress may be a necessary adaptive mechanism for survival and with only transient changes within the brain. However, severe and/or prolonged stress causes overactivation and dysregulation of the hypothalamic pituitary adrenal (HPA) axis thus inflicting detrimental changes in the brain structure and function. Therefore, chronic stress is often considered a negative modulator of the cognitive functions including the learning and memory processes. Exposure to long-lasting stress diminishes health and increases vulnerability to mental disorders. In addition, stress exacerbates functional changes associated with various brain disorders including Alzheimer’s disease and Parkinson’s disease. The primary purpose of this paper is to provide an overview for neuroscientists who are seeking a concise account of the effects of stress on learning and memory and associated signal transduction mechanisms. This review discusses chronic mental stress and its detrimental effects on various aspects of brain functions including learning and memory, synaptic plasticity, and cognition-related signaling enabled via key signal transduction molecules.
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Lee B, Sur B, Shim I, Lee H, Hahm DH. Baicalin improves chronic corticosterone-induced learning and memory deficits via the enhancement of impaired hippocampal brain-derived neurotrophic factor and cAMP response element-binding protein expression in the rat. J Nat Med 2013; 68:132-43. [DOI: 10.1007/s11418-013-0782-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 05/16/2013] [Indexed: 11/29/2022]
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21
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Role of α7- and α4β2-nAChRs in the neuroprotective effect of nicotine in stress-induced impairment of hippocampus-dependent memory. Int J Neuropsychopharmacol 2013; 16:1105-13. [PMID: 23067572 DOI: 10.1017/s1461145712001046] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We have previously shown that nicotine prevents stress-induced memory impairment. In this study, we have investigated the role of α7- and α4β2-nicotinic acetylcholine receptors (nAChRs) in the protective effect of nicotine during chronic stress conditions. Chronic psychosocial stress was induced using a form of rat intruder model. During stress, specific antagonist for either α7-nAChRs [methyllycaconitine (MLA)] or α4β2-nAChRs [dihydro-β-erythroidine (DHβE)] was infused into the hippocampus using a 4-wk osmotic pump at a rate of 82 μg/side.d and 41 μg/side.d, respectively. Three weeks after the start of infusion, all rats were subjected to a series of cognitive tests in the radial arm water maze (RAWM) for six consecutive days or until the animal reached days to criterion (DTC) in the fourth acquisition trial and in all memory tests. DTC is defined as the number of days the animal takes to make no more than one error in three consecutive days. In the short-term memory test, MLA-infused stressed/nicotine-treated rats made similar errors to those of stress and significantly more errors compared to those of stress/nicotine, nicotine or control groups. This finding was supported by the DTC values for the short memory tests. Thus, MLA treatment blocked the neuroprotective effect of nicotine during chronic stress. In contrast, DHβE infusion did not affect the RAWM performance of stress/nicotine animals. These results strongly suggest the involvement of α7-nAChRs, but not α4β2-nAChRs, in the neuroprotective effect of chronic nicotine treatment during chronic stress conditions.
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Alkadhi KA. Chronic stress and Alzheimer's disease-like pathogenesis in a rat model: prevention by nicotine. Curr Neuropharmacol 2012; 9:587-97. [PMID: 22654719 PMCID: PMC3263455 DOI: 10.2174/157015911798376307] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 02/10/2011] [Accepted: 06/10/2011] [Indexed: 01/08/2023] Open
Abstract
Environmental factors including chronic stress may play a critical role in the manifestation of Alzheimer's disease (AD).This review summarizes our studies of the aggravation of the impaired cognitive ability and its cellular and molecular correlates by chronic psychosocial stress and prevention by nicotine in an Aβ rat model of AD. We utilized three approaches: learning and memory tests in the radial arm water maze, electrophysiological recordings of the cellular correlates of memory, long-term potentiation (LTP) and long-term depression (LTD), in anesthetized rats, and immunoblot analysis of synaptic plasticity- and cognition-related signaling molecules. The Aβ rat model, representing the sporadic form of established AD, was induced by continuous i.c.v. infusion of a pathogenic dose of Aβ peptides via a 14- day osmotic pump. In this AD model, chronic stress intensified cognitive deficits, accentuated the disruption of signaling molecules levels and produced greater depression of LTP than what was seen with Aβ infusion alone. Chronic treatment with nicotine was highly efficient in preventing the effects of Aβ infusion and the exacerbating impact of chronic stress. Possible mechanisms for the effect of chronic stress are discussed.
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Affiliation(s)
- Karim A Alkadhi
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX 77204, USA
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Hritcu L, Stefan M, Brandsch R, Mihasan M. 6-hydroxy-l-nicotine from Arthrobacter nicotinovorans sustain spatial memory formation by decreasing brain oxidative stress in rats. J Physiol Biochem 2012; 69:25-34. [DOI: 10.1007/s13105-012-0184-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 06/05/2012] [Indexed: 12/31/2022]
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Elevation of BACE in an Aβ rat model of Alzheimer's disease: exacerbation by chronic stress and prevention by nicotine. Int J Neuropsychopharmacol 2012; 15:223-33. [PMID: 21356140 DOI: 10.1017/s1461145711000162] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In Alzheimer's disease (AD), progressive accumulation of β-amyloid (Aβ) peptides impairs nicotinic acetylcholine receptor (nAChR) function by a mechanism that may involve α7 and α4β2-nAChR subtypes. Additionally, the beta-site amyloid precursor protein (APP)-cleaving enzyme (BACE), the rate-limiting enzyme in the pathogenic Aβ production pathway, is expressed at high levels in hippocampal and cortical regions of AD brains. We measured hippocampal area CA1 protein levels of BACE and α7- and α4β2-nAChR subunits using an Aβ rat model of AD (14-d osmotic pump i.c.v. infusion of 300 pmol/d Aβ peptides) in the presence and absence of chronic stress and/or chronic nicotine treatment. There was a significant increase in the levels of BACE in Aβ-infused rats, which were markedly intensified by chronic (4-6 wk) stress, but were normalized in Aβ rats chronically treated with nicotine (1 mg/kg b.i.d.). The levels of the three subunits α7, α4 and β2 were significantly decreased in Aβ rats, but these were also normalized in Aβ rats chronically treated with nicotine. Chronic stress did not further aggravate the reduction of nAChRs in Aβ-infused rats. The increased BACE levels and decreased nAChR levels, which are established hallmarks of AD, provide additional support for the validity of the Aβ i.c.v.-infused rat as a model of AD.
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Martinho A, Gonçalves I, Costa M, Santos CR. Stress and Glucocorticoids Increase Transthyretin Expression in Rat Choroid Plexus via Mineralocorticoid and Glucocorticoid Receptors. J Mol Neurosci 2012; 48:1-13. [DOI: 10.1007/s12031-012-9715-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 01/27/2012] [Indexed: 01/18/2023]
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Changes in corticosteroid hormone receptors in the ischemic gerbil hippocampal CA1 region following repeated restraint stress. Neurochem Res 2011; 36:701-12. [PMID: 21207139 DOI: 10.1007/s11064-010-0384-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2010] [Indexed: 12/30/2022]
Abstract
Restraint stress produces physiological changes including suppression of long-term potentiation in the brain. We observed the effects of repeated stress on ischemic damage associated with corticosteroid hormone receptors in gerbils. Animals were placed into restrainers for 5 h (between 09:30 h and 14:30 h) for 21 consecutive days prior to induction of transient cerebral ischemia. The animals were divided into 4 groups; (1) sham-operated-control-group (sham-group), (2) ischemia-operated-control-group (ischemia-group), (3) sham-operated-stress-group (stressed-sham-group), and (4) ischemia-operated-stress-group (stressed-ischemia-group). We found that serum corticosterone level in the ischemia-group was highest (374% of the sham-group) 12 h after ischemia/reperfusion and its level in the stressed-ischemia-group was significantly lower than the ischemia-group. Locomotor activity in the ischemia-group was significantly increased (295% of the sham-group) at 1 day post-ischemia; however, the locomotor activity in the stressed-ischemia-group was less increased compared to the ischemia-group. Cresyl violet positive (CV(+)) cells were significantly decreased in the stratum pyramidale (SP) of the hippocampal CA1 region (CA1) of the 4 days post-ischemia-group, while 79.4% of CV(+) cells were detected in the CA1 of the stressed-ischemia-group. Also, a few NeuN (neuron-specific soluble nuclear antigen)(+) cells were detected in the SP of the 4 days post-ischemia-group; however, in the 4 days stressed-post-ischemia-group, 77.2% of NeuN(+) neurons were found in the SP. Glial fibrillary acidic protein(+) astrocytes in the CA1 in the stressed-ischemia-groups were similar to those in the ischemia-groups; however, ionized calcium-binding adapter molecule 1(+) microglia in the stressed-ischemia-groups were less activated compared to the ischemia-groups. Mineralocorticoid receptor (MCR) and glucocorticoid receptor (GR) immunoreactivity in the SP of the stressed-ischemia-group were higher than the ischemia-group; at 4 days post-ischemia, MCR and GR immunoreactivity were expressed in non-pyramidal cells. In brief, our results indicate that repeated restraint stress significantly increase levels of corticosteroid hormone receptors and attenuates neuronal damage in the ischemic hippocampal CA1 region.
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