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Ignjatović Đ, Nestorović N, Tomić M, Ristić N, Veličković N, Perović M, Manojlović-Stojanoski M. Effects of Prenatal Dexamethasone Treatment and Post-Weaning Moderate Fructose Intake on Synaptic Plasticity and Behavior in Adult Male Wistar Rat Offspring. BIOLOGY 2024; 13:547. [PMID: 39056739 PMCID: PMC11274266 DOI: 10.3390/biology13070547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Revised: 07/12/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024]
Abstract
Early-life glucocorticoid overexposure induces diverse neurodevelopmental outcomes regarding stress reactivity and cognition. Increased fructose consumption has also been associated with alterations in cognitive capacity and behavior. The present study investigated the effects of prenatal dexamethasone exposure on synaptic plasticity, locomotion, anxiety, and recognition memory in adult male Wistar rat offspring, and whether these effects are potentiated by postnatal fructose consumption. Pregnant female rats were treated with dexamethasone during late gestation and male offspring were supplemented with a moderate dose of fructose. Recognition memory, locomotion, and anxiety-like behavior were assessed using a novel object recognition test, open-field test, and elevated plus maze, respectively. Hippocampal synaptic plasticity was estimated by the levels of growth-associated protein 43 (GAP-43), synaptophysin, postsynaptic density protein 95, calcium/calmodulin-dependent kinase IIα, and their activating phosphorylations. Additionally, protein levels of the glucocorticoid receptor (GR) and its transcriptionally active phosphorylated form were evaluated. Prenatal dexamethasone treatment induced an anxiolytic-like effect, stimulation of exploratory behavior, and novelty preference associated with an increase in GR and GAP-43 protein levels in the hippocampus. Fructose overconsumption after weaning did not modify the effects of prenatal glucocorticoid exposure. Applied prenatal dexamethasone treatment may induce changes in reactions to novel situations in male Wistar rats.
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Affiliation(s)
- Đurđica Ignjatović
- Department of Biochemistry, Institute for Biological Research “Siniša Stanković”—National Institute of Republic of Serbia, University of Belgrade, 142 Despot Stefan Blvd., 11000 Belgrade, Serbia; (M.T.); (N.V.)
| | - Nataša Nestorović
- Department of Cytology, Institute for Biological Research “Siniša Stanković”—National Institute of Republic of Serbia, University of Belgrade, 142 Despot Stefan Blvd., 11000 Belgrade, Serbia; (N.N.); (N.R.)
| | - Mirko Tomić
- Department of Biochemistry, Institute for Biological Research “Siniša Stanković”—National Institute of Republic of Serbia, University of Belgrade, 142 Despot Stefan Blvd., 11000 Belgrade, Serbia; (M.T.); (N.V.)
| | - Nataša Ristić
- Department of Cytology, Institute for Biological Research “Siniša Stanković”—National Institute of Republic of Serbia, University of Belgrade, 142 Despot Stefan Blvd., 11000 Belgrade, Serbia; (N.N.); (N.R.)
| | - Nataša Veličković
- Department of Biochemistry, Institute for Biological Research “Siniša Stanković”—National Institute of Republic of Serbia, University of Belgrade, 142 Despot Stefan Blvd., 11000 Belgrade, Serbia; (M.T.); (N.V.)
| | - Milka Perović
- Department of Neurobiology, Institute for Biological Research “Siniša Stanković”—National Institute of Republic of Serbia, University of Belgrade, 142 Despot Stefan Blvd., 11000 Belgrade, Serbia;
| | - Milica Manojlović-Stojanoski
- Department of Cytology, Institute for Biological Research “Siniša Stanković”—National Institute of Republic of Serbia, University of Belgrade, 142 Despot Stefan Blvd., 11000 Belgrade, Serbia; (N.N.); (N.R.)
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2
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Seyedmirzaei H, Salmannezhad A, Ashayeri H, Shushtari A, Farazinia B, Heidari MM, Momayezi A, Shaki Baher S. Growth-Associated Protein 43 and Tensor-Based Morphometry Indices in Mild Cognitive Impairment. Neuroinformatics 2024; 22:239-250. [PMID: 38630411 DOI: 10.1007/s12021-024-09663-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2024] [Indexed: 08/17/2024]
Abstract
Growth-associated protein 43 (GAP-43) is found in the axonal terminal of neurons in the limbic system, which is affected in people with Alzheimer's disease (AD). We assumed GAP-43 may contribute to AD progression and serve as a biomarker. So, in a two-year follow-up study, we assessed GAP-43 changes and whether they are correlated with tensor-based morphometry (TBM) findings in patients with mild cognitive impairment (MCI). We included MCI and cognitively normal (CN) people with available baseline and follow-up cerebrospinal fluid (CSF) GAP-43 and TBM findings from the ADNI database. We assessed the difference between the two groups and correlations in each group at each time point. CSF GAP-43 and TBM measures were similar in the two study groups in all time points, except for the accelerated anatomical region of interest (ROI) of CN subjects that were significantly greater than those of MCI. The only significant correlations with GAP-43 observed were those inverse correlations with accelerated and non-accelerated anatomical ROI in MCI subjects at baseline. Plus, all TBM metrics decreased significantly in all study groups during the follow-up in contrast to CSF GAP-43 levels. Our study revealed significant associations between CSF GAP-43 levels and TBM indices among people of the AD spectrum.
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Affiliation(s)
- Homa Seyedmirzaei
- Sports Medicine Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Hamidreza Ashayeri
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Shushtari
- Faculty of Medicine , Mazandaran University of Medical Sciences, Sari, Iran.
| | - Bita Farazinia
- Faculty of Economics and Management, Shiraz Branch, Islamic Azad University, Shiraz, Iran
| | - Mohammad Mahdi Heidari
- Student Research Committee, Faculty of Medicine, Kashan University of Medical Sciences, Kashan, Iran
| | - Amirali Momayezi
- School of Chemical engineering, Iran University of Science and Technology, Tehran, Iran
| | - Sara Shaki Baher
- Faculty of Medicine, Tehran Branch, Islamic Azad University, Tehran, Iran
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3
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Hossein Geranmayeh M, Farokhi-Sisakht F, Sadigh-Eteghad S, Rahbarghazi R, Mahmoudi J, Farhoudi M. Simultaneous Pericytes and M2 Microglia Transplantation Improve Cognitive Function in Mice Model of mPFC Ischemia. Neuroscience 2023; 529:62-72. [PMID: 37591334 DOI: 10.1016/j.neuroscience.2023.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 07/27/2023] [Accepted: 08/04/2023] [Indexed: 08/19/2023]
Abstract
Cerebral ischemia is one of the major problems threatening global health. Many of the cerebral ischemia survivors would suffer from the physical and cognitive disabilities for their whole lifetime. Cell based-therapies have been introduced as a therapeutic approach for alleviating ischemia-enforced limitations. Photothrombotic stroke model was applied on the left medial prefrontal cortex (mPFC) of adult male BALB/c mice. Then, pericytes isolated from brain microvessels of adult male BALB/c mice, microglia isolated from brain cortices of the neonatal male BALB/c mice, and M2 phenotype shifted microglia by IL-4 treatment were used for transplantation into the injured area after 24 h of ischemia induction. The behavioural outcomes evaluated by social interaction and Barnes tests and the levels of growth associated protein (GAP)-43 and inflammatory cytokine interleukin (IL)-1 protein were assessed by western blotting 7 days after cell transplantation. Animals in both of the microglia + pericytes and microglia M2 + pericytes transplanted groups showed better performance in social memory as well as enhanced spatial learning and memory compared to ischemic controls. Also, improved escape latency was only observed in microglia M2 + pericytes (p < 0.01) group compared to ischemic controls. GAP-43 showed significant protein expression in microglia + pericytes and microglia M2 + pericytes groups compared to the control group. Conversely, IL-1 levels diminished in all of the pericytes microglia + pericytes, and microglia M2 + pericytes groups compared to the ischemic controls. Current study highlights efficiency of M2 microglia and pericytes combinatory transplantation therapeutic role on relieving ischemic stroke outcomes.
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Affiliation(s)
- Mohammad Hossein Geranmayeh
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, Iran; Stem Cells Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | | | - Saeed Sadigh-Eteghad
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Rahbarghazi
- Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Javad Mahmoudi
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mehdi Farhoudi
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, Iran.
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4
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Eleiwa NZH, Ali MAA, Said EN, Metwally MMM, Abd-ElHakim YM. Bee venom (Apis mellifera L.) rescues zinc oxide nanoparticles induced neurobehavioral and neurotoxic impact via controlling neurofilament and GAP-43 in rat brain. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:88685-88703. [PMID: 37442924 PMCID: PMC10412495 DOI: 10.1007/s11356-023-28538-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023]
Abstract
This study investigated the possible beneficial role of the bee venom (BV, Apis mellifera L.) against zinc oxide nanoparticles (ZNPs)-induced neurobehavioral and neurotoxic impacts in rats. Fifty male Sprague Dawley rats were alienated into five groups. Three groups were intraperitoneally injected distilled water (C 28D group), ZNPs (100 mg/kg b.wt) (ZNPs group), or ZNPs (100 mg/kg.wt) and BV (1 mg/ kg.bwt) (ZNPs + BV group) for 28 days. One group was intraperitoneally injected with 1 mL of distilled water for 56 days (C 56D group). The last group was intraperitoneally injected with ZNPs for 28 days, then BV for another 28 days at the same earlier doses and duration (ZNPs/BV group). Depression, anxiety, locomotor activity, spatial learning, and memory were evaluated using the forced swimming test, elevated plus maze, open field test, and Morris water maze test, respectively. The brain contents of dopamine, serotonin, total antioxidant capacity (TAC), malondialdehyde (MDA), and Zn were estimated. The histopathological changes and immunoexpressions of neurofilament and GAP-43 protein in the brain tissues were followed. The results displayed that BV significantly decreased the ZNPs-induced depression, anxiety, memory impairment, and spatial learning disorders. Moreover, the ZNPs-induced increment in serotonin and dopamine levels and Zn content was significantly suppressed by BV. Besides, BV significantly restored the depleted TAC but minimized the augmented MDA brain content associated with ZNPs exposure. Likewise, the neurodegenerative changes induced by ZNPs were significantly abolished by BV. Also, the increased neurofilament and GAP-43 immunoexpression due to ZNPs exposure were alleviated with BV. Of note, BV achieved better results in the ZNPs + BV group than in the ZNPs/BV group. Conclusively, these results demonstrated that BV could be employed as a biologically effective therapy to mitigate the neurotoxic and neurobehavioral effects of ZNPs, particularly when used during ZNPs exposure.
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Affiliation(s)
- Naglaa Z H Eleiwa
- Department of Pharmacology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Mahmoud Abo-Alkasem Ali
- Department of Pharmacology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Enas N Said
- Department of Behaviour and Management of Animal, Poultry and Aquatic, Faculty of Veterinary Medicine, Zagazig University, Zagazig, 44519, Egypt
| | - Mohamed M M Metwally
- Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, 44511, Egypt
| | - Yasmina M Abd-ElHakim
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
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5
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Cerebrospinal fluid growth-associated protein 43 levels in patients with progressive and stable mild cognitive impairment. Aging Clin Exp Res 2022; 34:2399-2406. [DOI: 10.1007/s40520-022-02202-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/17/2022] [Indexed: 11/25/2022]
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6
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Chen C, Bu L, Liu H, Rang Y, Huang H, Xiao X, Ou G, Liu C. Learning and memory impairment induced by 1,4-butanediol is regulated by ERK1/2-CREB-BDNF signaling pathways in PC12 cells. Metab Brain Dis 2022; 37:1451-1463. [PMID: 35348994 DOI: 10.1007/s11011-022-00963-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 03/14/2022] [Indexed: 01/03/2023]
Abstract
1,4-butanediol (1,4-BD) is a known γ-hydroxybutyric acid (GHB) precursor which affects the nervous system after ingestion, leading to uncontrolled behavioral consequences. In the present study, we investigated whether 1,4-BD induces oxidative stress and inflammation in PC12 cells and evaluated the toxic effects of 1,4-BD associates with learning and memory. CCK-8 results revealed a dose-effect relationship between the cell viability of PC12 cells and 1,4-BD when the duration of action was 2 h or 4 h. Assay kits results showed that 1,4-BD decreased the levels of Glutathione (GSH), Glutathione peroxidase (GSH-px), Superoxide dismutase (SOD), Acetylcholine (Ach) and increased the levels of Malondialdehyde (MDA), Nitric oxide (NO) and Acetylcholinesterase (AchE). Elisa kits results indicated that 1,4-BD decreased the levels of synaptophysin I (SYN-1), Postsynaptic density protein-95 (PSD-95), Growth associated protein-43 (GAP-43) and increased the levels of Tumor necrosis factor alpha (TNF-α) and Interleukin- 6 (IL-6). RT-PCR results showed that the mRNA levels of PSD-95, SYN-1 and GAP-43 were significantly decreased. The expression of phosphorylation extracellular signal-regulated protein kinase 1/2 (p-ERK1/2), phosphorylation cAMP response element binding protein (p-CREB) and brain-derived neurotrophic factor (BDNF) proteins were significantly decreased in PC12 cells by protein blotting. Overall, these results suggest that 1,4-BD may affect synaptic plasticity via the ERK1/2-CREB-BDNF pathway, leading to Ach release reduction and ultimately to learning and memory impairment. Furthermore, oxidative stress and inflammation induced by 1,4-BD may also result in learning and memory deficits. These findings will enrich the toxicity data of 1.4-BD associated with learning and memory impairment.
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Affiliation(s)
- Congying Chen
- College of Food Science, South China Agricultural University, Guang zhou, 510642, China
| | - Lingling Bu
- College of Food Science, South China Agricultural University, Guang zhou, 510642, China
| | - Huan Liu
- College of Food Science, South China Agricultural University, Guang zhou, 510642, China
| | - Yifeng Rang
- College of Food Science, South China Agricultural University, Guang zhou, 510642, China
| | - Huiying Huang
- College of Food Science, South China Agricultural University, Guang zhou, 510642, China
| | - Xueman Xiao
- College of Food Science, South China Agricultural University, Guang zhou, 510642, China
| | - Genghua Ou
- College of Food Science, South China Agricultural University, Guang zhou, 510642, China
| | - Chunhong Liu
- College of Food Science, South China Agricultural University, Guang zhou, 510642, China.
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7
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Aronson JP, Katnani HA, Huguenard A, Mulvaney G, Bader ER, Yang JC, Eskandar EN. Phasic stimulation in the nucleus accumbens enhances learning after traumatic brain injury. Cereb Cortex Commun 2022; 3:tgac016. [PMID: 35529519 PMCID: PMC9070350 DOI: 10.1093/texcom/tgac016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 03/31/2022] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Traumatic brain injury (TBI) is a significant cause of morbidity and mortality worldwide. Despite improvements in survival, treatments that improve functional outcome remain lacking. There is, therefore, a pressing need to develop novel treatments to improve functional recovery. Here, we investigated task-matched deep-brain stimulation of the nucleus accumbens (NAc) to augment reinforcement learning in a rodent model of TBI. We demonstrate that task-matched deep brain stimulation (DBS) of the NAc can enhance learning following TBI. We further demonstrate that animals receiving DBS exhibited greater behavioral improvement and enhanced neural proliferation. Treated animals recovered to an uninjured behavioral baseline and showed retention of improved performance even after stimulation was stopped. These results provide encouraging early evidence for the potential of NAc DBS to improve functional outcomes following TBI and that its effects may be broad, with alterations in neurogenesis and synaptogenesis.
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Affiliation(s)
- Joshua P Aronson
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Section of Neurosurgery, Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA
| | - Husam A Katnani
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Anna Huguenard
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Graham Mulvaney
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Edward R Bader
- Department of Neurological Surgery, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Jimmy C Yang
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Emad N Eskandar
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Department of Neurological Surgery, Albert Einstein College of Medicine, Bronx, NY, USA
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8
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Kumar D, Sharma A, Sharma L. A Comprehensive Review of Alzheimer's Association with Related Proteins: Pathological Role and Therapeutic Significance. Curr Neuropharmacol 2021; 18:674-695. [PMID: 32172687 PMCID: PMC7536827 DOI: 10.2174/1570159x18666200203101828] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 11/26/2019] [Accepted: 01/31/2020] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's is an insidious, progressive, chronic neurodegenerative disease which causes the devastation of neurons. Alzheimer's possesses complex pathologies of heterogeneous nature counting proteins as one major factor along with enzymes and mutated genes. Proteins such as amyloid precursor protein (APP), apolipoprotein E (ApoE), presenilin, mortalin, calbindin-D28K, creactive protein, heat shock proteins (HSPs), and prion protein are some of the chief elements in the foremost hypotheses of AD like amyloid-beta (Aβ) cascade hypothesis, tau hypothesis, cholinergic neuron damage, etc. Disturbed expression of these proteins results in synaptic dysfunction, cognitive impairment, memory loss, and neuronal degradation. On the therapeutic ground, attempts of developing anti-amyloid, anti-inflammatory, anti-tau therapies are on peak, having APP and tau as putative targets. Some proteins, e.g., HSPs, which ameliorate oxidative stress, calpains, which help in regulating synaptic plasticity, and calmodulin-like skin protein (CLSP) with its neuroprotective role are few promising future targets for developing anti-AD therapies. On diagnostic grounds of AD C-reactive protein, pentraxins, collapsin response mediator protein-2, and growth-associated protein-43 represent the future of new possible biomarkers for diagnosing AD. The last few decades were concentrated over identifying and studying protein targets of AD. Here, we reviewed the physiological/pathological roles and therapeutic significance of nearly all the proteins associated with AD that addresses putative as well as probable targets for developing effective anti-AD therapies.
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Affiliation(s)
- Deepak Kumar
- School of Pharmaceutical Sciences, Shoolini University, Solan, H.P., India
| | - Aditi Sharma
- School of Pharmaceutical Sciences, Shoolini University, Solan, H.P., India
| | - Lalit Sharma
- School of Pharmaceutical Sciences, Shoolini University, Solan, H.P., India
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9
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Durán-Carabali LE, Odorcyk FK, Greggio S, Venturin GT, Sanches EF, Schu GG, Carvalho AS, Pedroso TA, de Sá Couto-Pereira N, Da Costa JC, Dalmaz C, Zimmer ER, Netto CA. Pre- and early postnatal enriched environmental experiences prevent neonatal hypoxia-ischemia late neurodegeneration via metabolic and neuroplastic mechanisms. J Neurochem 2020; 157:1911-1929. [PMID: 33098090 DOI: 10.1111/jnc.15221] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/04/2020] [Accepted: 10/19/2020] [Indexed: 12/17/2022]
Abstract
Prenatal and early postnatal periods are important for brain development and neural function. Neonatal insults such as hypoxia-ischemia (HI) causes prolonged neural and metabolic dysregulation, affecting central nervous system maturation. There is evidence that brain hypometabolism could increase the risk of adult-onset neurodegenerative diseases. However, the impact of non-pharmacologic strategies to attenuate HI-induced brain glucose dysfunction is still underexplored. This study investigated the long-term effects of early environmental enrichment in metabolic, cell, and functional responses after neonatal HI. Thereby, male Wistar rats were divided according to surgical procedure, sham, and HI (performed at postnatal day 3), and the allocation to standard (SC) or enriched condition (EC) during gestation and lactation periods. In-vivo cerebral metabolism was assessed by means of [18 F]-FDG micro-positron emission tomography, and cognitive, biochemical, and histological analyses were performed in adulthood. Our findings reveal that HI causes a reduction in glucose metabolism and glucose transporter levels as well as hyposynchronicity in metabolic brain networks. However, EC during prenatal or early postnatal period attenuated these metabolic disturbances. A positive correlation was observed between [18 F]-FDG values and volume ratios in adulthood, indicating that preserved tissue by EC is metabolically active. EC promotes better cognitive scores, as well as down-regulation of amyloid precursor protein in the parietal cortex and hippocampus of HI animals. Furthermore, growth-associated protein 43 was up-regulated in the cortex of EC animals. Altogether, results presented support that EC during gestation and lactation period can reduce HI-induced impairments that may contribute to functional decline and progressive late neurodegeneration.
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Affiliation(s)
- Luz Elena Durán-Carabali
- Graduate Program in Biological Sciences: Physiology, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Felipe Kawa Odorcyk
- Graduate Program in Biological Sciences: Physiology, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Samuel Greggio
- Preclinical Research Center, Brain Institute (BraIns) of Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Eduardo Farias Sanches
- Graduate Program in Biological Sciences: Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Guilherme Garcia Schu
- Graduate Program in Biological Sciences: Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Andrey Soares Carvalho
- Graduate Program in Biological Sciences: Neuroscience, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Thales Avila Pedroso
- Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Natividade de Sá Couto-Pereira
- Graduate Program in Biological Sciences: Neuroscience, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Jaderson Costa Da Costa
- Preclinical Research Center, Brain Institute (BraIns) of Rio Grande do Sul, Porto Alegre, Brazil
| | - Carla Dalmaz
- Graduate Program in Biological Sciences: Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Graduate Program in Biological Sciences: Neuroscience, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Eduardo Rigon Zimmer
- Graduate Program in Biological Sciences: Pharmacology and Therapeutics, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Department of Pharmacology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Carlos Alexandre Netto
- Graduate Program in Biological Sciences: Physiology, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Graduate Program in Biological Sciences: Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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10
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Grijalva LE, Miranda MI, Paredes RG. Differential changes in GAP-43 or synaptophysin during appetitive and aversive taste memory formation. Behav Brain Res 2020; 397:112937. [PMID: 32991926 DOI: 10.1016/j.bbr.2020.112937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 09/19/2020] [Accepted: 09/21/2020] [Indexed: 10/23/2022]
Abstract
Association between events in time and space is a major mechanism for all animals, including humans, which allows them to learn about the world and potentially change their behavior in the future to adapt to different environments. Conditioning taste aversion (CTA) is a single-trial learning paradigm where animals are trained to avoid a novel flavor which is associated with malaise. Many variables can be analyzed with this model and the circuits involved are well described. Thus, the amygdala and the gustatory cortex (GC) are some of the most relevant structures involved in CTA. In the present study we focused in plastic changes that occur during appetitive and/or aversive taste memory formation. Previous studies have demonstrated that memory consolidation, in hippocampal dependent paradigms, induces plastic changes like increase in the concentration of proteins considered as markers of neuronal plasticity, such as the growth associated protein 43 (GAP-43) and synaptophysin (SYN). In the present experiment in male rats we evaluated changes in GAP-43 and SYN expression, using immunofluorescence, induce by the formation of aversive and appetitive taste memory. We found that taste aversive memory formation can induce an increase in GAP-43 in the granular layer of the GC. Furthermore, we also found an increase in SYN expression in both layers of the GC, the basolateral amygdala (BLA) and the central amygdala (CeA). These results suggest that aversive memory representation induces a new circuitry (inferred from an increase in GAP 43). On the other hand, an appetitive taste learning increased SYN expression in the GC (both layers), the BLA and the CeA without any changes in GAP 43. Together these results indicate that aversive memory formation induces structural and synaptic changes, while appetitive memory formation induces synaptic changes; suggesting that aversive and appetitive memories require a different set of cortical and amygdala plastic changes.
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Affiliation(s)
- Lucia E Grijalva
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, 76230, Mexico
| | - María I Miranda
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, 76230, Mexico
| | - Raúl G Paredes
- Instituto de Neurobiología, UNAM, Campus Juriquilla, Querétaro, 76230, Mexico; Escuela Nacional de Estudios Superiores, Unidad Juriquilla, UNAM, Querétaro, 76230 Mexico.
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11
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Keshvari M, Rahmati M, Mirnasouri R, Chehelcheraghi F. Effects of endurance exercise and Urtica dioica on the functional, histological and molecular aspects of the hippocampus in STZ-Induced diabetic rats. JOURNAL OF ETHNOPHARMACOLOGY 2020; 256:112801. [PMID: 32247145 DOI: 10.1016/j.jep.2020.112801] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 03/17/2020] [Accepted: 03/25/2020] [Indexed: 02/07/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Many body systems and organs, including the hippocampus, are affected by diabetes, and undergo changes that may increase the risk of cognitive decline. Urtica dioica (UD) has long been recognized as a medicinal plant with beneficial effects on blood glucose control in diabetes. AIM OF THE STUDY The present study aimed to investigate the effect of endurance exercise (Ex), along with Urtica dioica (UD) hydro-alcoholic extract on some functional, histological, and molecular aspects of the hippocampus in streptozotocin (STZ)-induced diabetic rats. MATERIALS AND METHODS 60 male Wistar rats were divided into five groups (N = 12): healthy control (H-C), diabetes control (D-C), diabetes exercise (D-Ex), diabetes Urtica dioica (D-UD), and diabetes exercise Urtica dioica (D-Ex-UD). Diabetes was induced intraperitoneally by STZ (45 mg/kg) injection. Two weeks after the injection by STZ, Ex (moderate intensity/5day/week) and gavage of UD extract (50mg/kg/day) was performed for six weeks. Cognitive functions were evaluated by the Morris Water Maze test, routine histological examination, and molecular studies were done via Hematoxylin & Eosin stain, and Western blot. RESULTS Diabetic rats showed spatial learning and memory deficits, as well as negatively affects to the tissue and structure of the hippocampus in the dentate gyrus (DG) and cornu ammonis (CA) areas. Ex + UD treatment caused a decrease of neural disorganization, an increase of neural-microglial density, and thickness of the pyramidal-molecular layer in the hippocampus. In addition, Ex + UD caused a rise of GAP-43 protein levels, a reduction of CAP-1 protein levels, improved hippocampal structure, and improved learning and memory function. CONCLUSIONS These results show that Ex, along with the UD extract, may decrease levels of the central neural complications of diabetes. Given the importance of recognizing non-pharmacological complementary therapies in this field, future studies are warranted.
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Affiliation(s)
- Maryam Keshvari
- Sport Sciences Department, Faculty of Literature and Human Sciences, Lorestan University, Khorramabad, Iran.
| | - Masoud Rahmati
- Sport Sciences Department, Faculty of Literature and Human Sciences, Lorestan University, Khorramabad, Iran.
| | - Rahim Mirnasouri
- Sport Sciences Department, Faculty of Literature and Human Sciences, Lorestan University, Khorramabad, Iran.
| | - Farzaneh Chehelcheraghi
- Anatomical Sciences Department, School of Medicine, Lorestan University Medical of Sciences, Khorramabad, Iran.
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12
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Li Q, Wu X, Na X, Ge B, Wu Q, Guo X, Ntim M, Zhang Y, Sun Y, Yang J, Xiao Z, Zhao J, Li S. Impaired Cognitive Function and Altered Hippocampal Synaptic Plasticity in Mice Lacking Dermatan Sulfotransferase Chst14/D4st1. Front Mol Neurosci 2019; 12:26. [PMID: 30853887 PMCID: PMC6396735 DOI: 10.3389/fnmol.2019.00026] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 01/21/2019] [Indexed: 12/23/2022] Open
Abstract
Chondroitin sulfate (CS) and dermatan sulfate (DS) proteoglycans (PGs) are major extracellular matrix (ECM) components of the central nervous system (CNS). A large body of evidence has shown that CSPGs/DSPGs play critical roles in neuronal growth, axon guidance, and plasticity in the developing and mature CNS. It has been proposed that these PGs exert their function through specific interaction of CS/DS chains with its binding partners in a manner that depends on the sulfation patterns of CS/DS. It has been reported that dermatan 4-O-sulfotransferase-1 (Chst14/D4st1) specific for DS, but not chondroitin 4-O-sulfotransferase-1 (Chst11/C4st1) specific for CS, regulates proliferation and neurogenesis of neural stem cells (NSCs), indicating that CS and DS play distinct roles in the self-renewal and differentiation of NSCs. However, it remains unknown whether specific sulfation profiles of DS has any effect on CNS plasticity. In the present study, Chst14/D4st1-deficient (Chst14−/−) mice was employed to investigate the involvement of DS in synaptic plasticity. First, behavior study using Morris Water Maze (MWM) showed that the spatial learning and memory of Chst14−/− mice was impaired when compared to their wild type (WT) littermates. Corroborating the behavior result, long-term potentiation (LTP) at the hippocampal CA3-CA1 connection was reduced in Chst14−/− mice compared to the WT mice. Finally, the protein levels of N-Methyl-D-aspartate (NMDA) receptor, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor, postsynaptic density 95 (PSD95), growth associated protein 43 (GAP-43), synaptophysin (SYN) and N-ethylmaleimide sensitive factor (NSF) which are important in synaptic plasticity were examined and Chst14/D4st1 deficiency was shown to significantly reduce the expression of these proteins in the hippocampus. Further studies revealed that Akt/mammalian target rapamycin (mTOR) pathway proteins, including protein kinase B (p-Akt), p-mTOR and p-S6, were significantly lower in Chst14−/− mice, which might contribute to the decreased protein expression. Together, this study reveals that specific sulfation of DS is critical in synaptic plasticity of the hippocampus and learning and memory, which might be associated with the changes in the expression of glutamate receptors and other synaptic proteins though Akt/mTOR pathway.
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Affiliation(s)
- Qifa Li
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
| | - Xuefei Wu
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
| | - Xueyan Na
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
| | - Biying Ge
- National-Local Joint Engineering Research Center for Drug-Research and Development (R & D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, China
| | - Qiong Wu
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
| | - Xuewen Guo
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
| | - Michael Ntim
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
| | - Yue Zhang
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
| | - Yiping Sun
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
| | - Jinyi Yang
- Department of Urology, Dalian Friendship Hospital, Dalian, China
| | - Zhicheng Xiao
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, VIC, Australia
| | - Jie Zhao
- National-Local Joint Engineering Research Center for Drug-Research and Development (R & D) of Neurodegenerative Diseases, Dalian Medical University, Dalian, China
| | - Shao Li
- Liaoning Provincial Key Laboratory of Cerebral Diseases, Department of Physiology, Dalian Medical University, Dalian, China
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13
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Zamzow DR, Elias V, Acosta VA, Escobedo E, Magnusson KR. Higher Levels of Protein Palmitoylation in the Frontal Cortex across Aging Were Associated with Reference Memory and Executive Function Declines. eNeuro 2019; 6:ENEURO.0310-18.2019. [PMID: 30740518 PMCID: PMC6366935 DOI: 10.1523/eneuro.0310-18.2019] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 01/04/2019] [Accepted: 01/08/2019] [Indexed: 12/17/2022] Open
Abstract
Cognitive decline with aging is often due to altered levels of protein expression. The NMDA receptor (NMDAR) and the complex of proteins surrounding the receptor are susceptible to age-related changes in expression. In the frontal cortex of aged mice, there is a significant loss of expression of the GluN2B subunit of the NMDAR, an increase in Fyn expression, and no change in PSD-95. Studies have also found that, in the frontal cortex, phosphorylation of GluN2B subunits and palmitoylation of GluN2 subunits and NMDAR complex proteins are affected by age. In this study, we examined some of the factors that may lead to the differences in the palmitoylation levels of NMDAR complex proteins in the frontal cortex of aged animals. The Morris water maze was used to test spatial learning in 3- and 24-month-old mice. The acyl-biotinyl exchange method was used to precipitate palmitoylated proteins from the frontal cortices and hippocampi of the mice. Additionally, brain lysates from old and young mice were probed for the expression of fatty acid transporter proteins. An age-related increase of palmitoylated GluN2A, GluN2B, Fyn, PSD-95, and APT1 (acyl protein thioesterase 1) in the frontal cortex was associated with poorer reference memory and/or executive functions. These data suggest that there may be a perturbation in the palmitoylation cycle in the frontal cortex of aged mice that contributes to age-related cognitive declines.
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Affiliation(s)
| | - Valerie Elias
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon 97331
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon 97331
| | - Varinia A. Acosta
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon 97331
| | - Emily Escobedo
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon 97331
| | - Kathy R. Magnusson
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon 97331
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon 97331
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14
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Mercerón-Martínez D, Almaguer-Melian W, Alberti-Amador E, Bergado JA. Amygdala stimulation promotes recovery of behavioral performance in a spatial memory task and increases GAP-43 and MAP-2 in the hippocampus and prefrontal cortex of male rats. Brain Res Bull 2018; 142:8-17. [PMID: 29933038 DOI: 10.1016/j.brainresbull.2018.06.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 06/15/2018] [Indexed: 01/22/2023]
Abstract
The relationships between affective and cognitive processes are an important issue of present neuroscience. The amygdala, the hippocampus and the prefrontal cortex appear as main players in these mechanisms. We have shown that post-training electrical stimulation of the basolateral amygdala (BLA) speeds the acquisition of a motor skill, and produces a recovery in behavioral performance related to spatial memory in fimbria-fornix (FF) lesioned animals. BLA electrical stimulation rises bdnf RNA expression, BDNF protein levels, and arc RNA expression in the hippocampus. In the present paper we have measured the levels of one presynaptic protein (GAP-43) and one postsynaptic protein (MAP-2) both involved in synaptogenesis to assess whether structural neuroplastic mechanisms are involved in the memory enhancing effects of BLA stimulation. A single train of BLA stimulation produced in healthy animals an increase in the levels of GAP-43 and MAP-2 that lasted days in the hippocampus and the prefrontal cortex. In FF-lesioned rats, daily post-training stimulation of the BLA ameliorates the memory deficit of the animals and induces an increase in the level of both proteins. These results support the hypothesis that the effects of amygdala stimulation on memory recovery are sustained by an enhanced formation of new synapses.
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Affiliation(s)
- D Mercerón-Martínez
- Laboratorio de Electrofisiología Experimental, International Center for Neurological Restoration (CIREN), Ave. 25 No. 15806, entre 156 y 158, Playa 11300, Havana City, Cuba.
| | - W Almaguer-Melian
- Laboratorio de Electrofisiología Experimental, International Center for Neurological Restoration (CIREN), Ave. 25 No. 15806, entre 156 y 158, Playa 11300, Havana City, Cuba.
| | - E Alberti-Amador
- Lab. Biología Molecular, International Center for Neurological Restoration (CIREN), Ave. 25 No. 15806, entre 156 y 158, Playa, Havana City, 11300, Cuba.
| | - J A Bergado
- Universidad del Sinú "Elías Bechara Zainum", Cra. 1w No. 38-153, Barrio Juan XXIII, Montería, Córdoba, 4536534, Colombia.
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15
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Growth Associated Protein 43 (GAP-43) as a Novel Target for the Diagnosis, Treatment and Prevention of Epileptogenesis. Sci Rep 2017; 7:17702. [PMID: 29255203 PMCID: PMC5735087 DOI: 10.1038/s41598-017-17377-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 11/21/2017] [Indexed: 12/19/2022] Open
Abstract
We previously showed increased growth associated protein 43 (GAP-43) expression in brain samples resected from patients with cortical dysplasia (CD), which was correlated with duration of epilepsy. Here, we used a rat model of CD to examine the regulation of GAP-43 in the brain and serum over the course of epileptogenesis. Baseline GAP-43 expression was higher in CD animals compared to control non-CD rats. An acute seizure increased GAP-43 expression in both CD and control rats. However, GAP-43 expression decreased by day 15 post-seizure in control rats, which did not develop spontaneous seizures. In contrast, GAP-43 remained up-regulated in CD rats, and over 50% developed chronic epilepsy with increased GAP-43 levels in their serum. GAP-43 protein was primarily located in excitatory neurons, suggesting its functional significance in epileptogenesis. Inhibition of GAP-43 expression by shRNA significantly reduced seizure duration and severity in CD rats after acute seizures with subsequent reduction in interictal spiking. Serum GAP-43 levels were significantly higher in CD rats that developed spontaneous seizures. Together, these results suggest GAP-43 as a key factor promoting epileptogenesis, a possible therapeutic target for treatment of progressive epilepsy and a potential biomarker for epilepsy progression in CD.
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16
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Holahan MR. A Shift from a Pivotal to Supporting Role for the Growth-Associated Protein (GAP-43) in the Coordination of Axonal Structural and Functional Plasticity. Front Cell Neurosci 2017; 11:266. [PMID: 28912688 PMCID: PMC5583208 DOI: 10.3389/fncel.2017.00266] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 08/18/2017] [Indexed: 11/14/2022] Open
Abstract
In a number of animal species, the growth-associated protein (GAP), GAP-43 (aka: F1, neuromodulin, B-50, G50, pp46), has been implicated in the regulation of presynaptic vesicular function and axonal growth and plasticity via its own biochemical properties and interactions with a number of other presynaptic proteins. Changes in the expression of GAP-43 mRNA or distribution of the protein coincide with axonal outgrowth as a consequence of neuronal damage and presynaptic rearrangement that would occur following instances of elevated patterned neural activity including memory formation and development. While functional enhancement in GAP-43 mRNA and/or protein activity has historically been hypothesized as a central mediator of axonal neuroplastic and regenerative responses in the central nervous system, it does not appear to be the crucial substrate sufficient for driving these responses. This review explores the historical discovery of GAP-43 (and associated monikers), its transcriptional, post-transcriptional and post-translational regulation and current understanding of protein interactions and regulation with respect to its role in axonal function. While GAP-43 itself appears to have moved from a pivotal to a supporting factor, there is no doubt that investigations into its functions have provided a clearer understanding of the biochemical underpinnings of axonal plasticity.
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17
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Cheon S. Hippocampus-dependent Task Improves the Cognitive Function after Ovariectomy in Rats. Osong Public Health Res Perspect 2017; 8:227-234. [PMID: 28781946 PMCID: PMC5525566 DOI: 10.24171/j.phrp.2017.8.3.10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/02/2017] [Accepted: 06/04/2017] [Indexed: 11/11/2022] Open
Abstract
Objectives Estrogen is an important hormone for cell growth, development, and differentiation by transcriptional regulation and modulation of intracellular signaling via second messengers. The reduction in the estrogen level after ovariectomy may lead to cognitive impairments associated with morphological changes in areas of the brain mediate memory. The aim of the present study was to find out the effect of tasks on the cognitive function after ovariectomy in rats. Methods The animals used in the experiment were 50 Sprague-Dawley female rats. This study applied a hippocampus-independent task (wheel running) and a hippocampus-dependent task (Morris water maze) after ovariectomy in rats and measured the cognitive performance (object-recognition and object-location test) and growth-associated protein 43 (GAP-43) and neurotrophin 3 (NT-3) expression in the hippocampus, which is an important center for memory and learning. Results There were meaningful differences between the hippocampus-independent and hippocampus-dependent task groups for the object-location test and GAP-43 and NT-3 expression in the hippocampus, but not the object-recognition test. However, the hippocampus-independent task group showed a significant improvement in the object-recognition test, compared to the control group. Conclusion These results suggest that hippocampus-dependent task training after ovariectomy enhances the hippocampus-related memory and cognitive function that are associated with morphological and functional changes in the cells of the hippocampus.
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Affiliation(s)
- Songhee Cheon
- Department of Physical Therapy, College of Health Science, Youngsan University, Yangsan, Korea
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18
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Marques-Carneiro JE, Persike DS, Litzahn JJ, Cassel JC, Nehlig A, Fernandes MJDS. Hippocampal Proteome of Rats Subjected to the Li-Pilocarpine Epilepsy Model and the Effect of Carisbamate Treatment. Pharmaceuticals (Basel) 2017; 10:ph10030067. [PMID: 28758946 PMCID: PMC5620611 DOI: 10.3390/ph10030067] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/26/2017] [Accepted: 07/27/2017] [Indexed: 12/17/2022] Open
Abstract
In adult rats, the administration of lithium–pilocarpine (LiPilo) reproduces most clinical and neuropathological features of human temporal lobe epilepsy (TLE). Carisbamate (CRS) possesses the property of modifying epileptogenesis in this model. Indeed, about 50% of rats subjected to LiPilo status epilepticus (SE) develop non-convulsive seizures (NCS) instead of motor seizures when treated with CRS. However, the mechanisms underlying these effects remain unknown. The aim of this study was to perform a proteomic analysis in the hippocampus of rats receiving LiPilo and developing motor seizures or NCS following CRS treatment. Fifteen adult male Sprague–Dawley rats were used. SE was induced by LiPilo injection. CRS treatment was initiated at 1 h and 9 h after SE onset and maintained for 7 days, twice daily. Four groups were studied after video-EEG control of the occurrence of motor seizures: a control group receiving saline (CT n = 3) and three groups that underwent SE: rats treated with diazepam (DZP n = 4), rats treated with CRS displaying NCS (CRS-NCS n = 4) or motor seizures (CRS-TLE n = 4). Proteomic analysis was conducted by 2D-SDS-PAGE. Twenty-four proteins were found altered. In the CRS-NCS group, proteins related to glycolysis and ATP synthesis were down-regulated while proteins associated with pyruvate catabolism were up-regulated. Moreover, among the other proteins differentially expressed, we found proteins related to inflammatory processes, protein folding, tissue regeneration, response to oxidative stress, gene expression, biogenesis of synaptic vesicles, signal transduction, axonal transport, microtubule formation, cell survival, and neuronal plasticity. Our results suggest a global reduction of glycolysis and cellular energy production that might affect brain excitability. In addition, CRS seems to modulate proteins related to many other pathways that could significantly participate in the epileptogenesis-modifying effect observed.
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Affiliation(s)
- José Eduardo Marques-Carneiro
- Departamento de Neurologia e Neurocirurgia, Disciplina Neurociência, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP 04039-032 São Paulo, Brazil.
- Unistra, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, Université de Strasbourg, 67000 Strasbourg, France.
- CNRS, UMR 7364, LNCA, 12 rue Goethe, 67000 Strasbourg, France.
| | - Daniele Suzete Persike
- Departamento de Neurologia e Neurocirurgia, Disciplina Neurociência, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP 04039-032 São Paulo, Brazil.
| | - Julia Julie Litzahn
- Departamento de Neurologia e Neurocirurgia, Disciplina Neurociência, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP 04039-032 São Paulo, Brazil.
| | - Jean-Christophe Cassel
- Unistra, Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Faculté de Psychologie, Université de Strasbourg, 67000 Strasbourg, France.
- CNRS, UMR 7364, LNCA, 12 rue Goethe, 67000 Strasbourg, France.
| | - Astrid Nehlig
- INSERM U 1129 "Infantile Epilepsies and Brain Plasticity", 75015 Paris, France.
- Université Paris Descartes, Sorbonne Paris Cité, CEA, 91990 Gif sur Yvette, France.
| | - Maria José da Silva Fernandes
- Departamento de Neurologia e Neurocirurgia, Disciplina Neurociência, Escola Paulista de Medicina, Universidade Federal de São Paulo, SP 04039-032 São Paulo, Brazil.
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Li W, Zhu Y, Saud SM, Guo Q, Xi S, Jia B, Jiao S, Yang X, Lu J, Song S, Tu Y. Electroacupuncture relieves depression-like symptoms in rats exposed to chronic unpredictable mild stress by activating ERK signaling pathway. Neurosci Lett 2017; 642:43-50. [PMID: 28147225 DOI: 10.1016/j.neulet.2017.01.060] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 01/25/2017] [Accepted: 01/25/2017] [Indexed: 12/25/2022]
Abstract
Electroacupuncture (EA) has been shown to alleviate the symptoms associated with major depressive disorder; however, the underlying mechanisms remain unclear. While the mainstay treatment for depression are pharmacological agents that modulate serotonergic and/or noradrenergic activity of the brain, recent data suggest that, neurotrophins may play a larger role in the pathogenesis of depression and may offer better therapeutic potential in alleviating symptoms associated with depression. One downstream target of neurotrophins is the extracellular signal-regulated kinase (ERK)/Mitogen-activated protein kinase (MAPK) cascade, a major mediator of cellular stress often associated with clinical depression. In this study, we assessed whether the efficacy of EA is due to regulation of these novel pathways using an animal model of depression induced by chronic unpredictable mild stress (CUMS). We found that EA stimulation at specific locations, Baihui (GV20), and Yintang (GV29) ameliorated the behavioral responses of CUMS, which included reduced locomotion, decreased sucrose intake and weight loss. Furthermore, EA increased the activation of ERK and ribosomal s6 kinase (RSK) levels under stress. Both the behavioral and biochemical responses to EA were attenuated with administration of ERK inhibitor, suggesting that EA improves depression-like symptoms in stressed rats, in part, by activation of ERK signaling.
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Affiliation(s)
- Weidong Li
- Department of Scientific Research Management, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing 100053, China.
| | - Yan Zhu
- Xi'an XD Group Hospital, Xi'an 710077, China
| | - Shakir M Saud
- Department of Cell Biology and Molecular Medicine, New Jersey Medical School, Newark, NJ 07103, USA
| | - Qiujun Guo
- Oncology Department, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing 100053, China
| | - Shengyan Xi
- Department of Traditional Chinese Medicine, Medical College of the Xiamen University, Xiamen 361102, China
| | - Baohui Jia
- Department of Acupuncture, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing 100053, China
| | - Shuang Jiao
- Editorial department, Journal of Traditional Chinese Medicine, China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Xiuyan Yang
- School of Acupuncture-Moxibustion and Tui Na, Beijing University of Chinese Medicine, Beijing 100029, China
| | - Jun Lu
- School of Acupuncture-Moxibustion and Tui Na, Beijing University of Chinese Medicine, Beijing 100029, China
| | - Sihong Song
- Department of Pharmaceutics, University of Florida, Gainesville, FL 32610, USA
| | - Ya Tu
- School of Acupuncture-Moxibustion and Tui Na, Beijing University of Chinese Medicine, Beijing 100029, China.
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20
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Lee YS, Lee JA, Kaang BK. Regulation of mRNA stability by ARE-binding proteins in synaptic plasticity and memory. Neurobiol Learn Mem 2015; 124:28-33. [PMID: 26291750 DOI: 10.1016/j.nlm.2015.08.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 08/01/2015] [Accepted: 08/03/2015] [Indexed: 11/27/2022]
Abstract
Formation of long-term memories requires coordinated gene expression, which can be regulated at transcriptional, post-transcriptional, and translational levels. Post-transcriptional stabilization and destabilization of mRNAs provides precise temporal and spatial regulation of gene expression, which is critical for consolidation of synaptic plasticity and memory. mRNA stability is regulated by interactions between the cis-acting elements of mRNAs, such as adenine-uridine-rich elements (AREs), and the trans-acting elements, ARE-binding proteins (AUBPs). There are several AUBPs in the nervous system. Among AUBPs, Hu/ELAV-like proteins and AUF1 are the most studied mRNA stabilizing and destabilizing factors, respectively. Here, we summarize compelling evidence for critical roles of these AUBPs in synaptic plasticity, as well as learning and memory, in both vertebrates and invertebrates. Furthermore, we also briefly review the deregulations of AUBPs in neurological disorders.
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Affiliation(s)
- Yong-Seok Lee
- Department of Life Science, College of Natural Sciences, Chung-Ang University, Seoul, South Korea.
| | - Jin-A Lee
- Department of Biotechnology and Biological Sciences, Hannam University, Daejeon, South Korea
| | - Bong-Kiun Kaang
- Department of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul, South Korea.
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21
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Zhao H, Li Z, Wang Y, Zhang Q. Hippocampal expression of synaptic structural proteins and phosphorylated cAMP response element-binding protein in a rat model of vascular dementia induced by chronic cerebral hypoperfusion. Neural Regen Res 2015; 7:821-6. [PMID: 25737708 PMCID: PMC4342708 DOI: 10.3969/j.issn.1673-5374.2012.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 02/24/2012] [Indexed: 12/27/2022] Open
Abstract
The present study established a rat model of vascular dementia induced by chronic cerebral hypoperfusion through permanent ligation of bilateral common carotid arteries. At 60 days after modeling, escape latency and swimming path length during hidden-platform acquisition training in Morris water maze significantly increased in the model group. In addition, the number of accurate crossings over the original platform significantly decreased, hippocampal CA1 synaptophysin and growth-associated protein 43 expression significantly decreased, cAMP response element-binding protein expression remained unchanged, and phosphorylated cAMP response element-binding protein expression significantly decreased. Results suggested that abnormal expression of hippocampal synaptic structural protein and cAMP response element-binding protein phosphorylation played a role in cognitive impairment following chronic cerebral hypoperfusion.
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Affiliation(s)
- Hui Zhao
- School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, China
| | - Zhiyong Li
- China Minority Traditional Medical Center, Minzu University of China, Beijing 100081, China
| | - Yali Wang
- School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, China
| | - Qiuxia Zhang
- School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, China
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22
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Latchney SE, Masiulis I, Zaccaria KJ, Lagace DC, Powell CM, McCasland JS, Eisch AJ. Developmental and adult GAP-43 deficiency in mice dynamically alters hippocampal neurogenesis and mossy fiber volume. Dev Neurosci 2014; 36:44-63. [PMID: 24576816 DOI: 10.1159/000357840] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 12/09/2013] [Indexed: 12/29/2022] Open
Abstract
Growth-associated protein-43 (GAP-43) is a presynaptic protein that plays key roles in axonal growth and guidance and in modulating synapse formation. Previous work has demonstrated that mice lacking one allele of this gene (GAP-43+/- mice) exhibit hippocampal structural abnormalities, impaired spatial learning and stress-induced behavioral withdrawal and anxiety, behaviors that are dependent on proper hippocampal circuitry and function. Given the correlation between hippocampal function, synaptic connectivity and neurogenesis, we tested if behaviorally naïve GAP-43+/- mice had alterations in either neurogenesis or synaptic connectivity in the hippocampus during early postnatal development and young adulthood, and following behavior testing in older adults. To test our hypothesis, we examined hippocampal cell proliferation (Ki67), number of immature neuroblasts (doublecortin, DCX) and mossy fiber volume (synaptoporin) in behaviorally naïve postnatal day 9 (P9) and P26, and behaviorally experienced 5- to 7-month-old GAP-43+/- and +/+ littermate mice. P9 GAP-43+/- mice had fewer Ki67+ and DCX+ cells compared to +/+ mice, particularly in the posterior dentate gyrus, and smaller mossy fiber volume in the same region. In young adulthood, however, male GAP-43+/- mice had more Ki67+ and DCX+ cells and greater mossy fiber volume in the posterior dentate gyrus relative to male +/+ mice. These increases were not seen in females. In 5- to 7-month-old GAP-43+/- mice (whose behaviors were the focus of our prior publication), there was no global change in the number of proliferating or immature neurons relative to +/+ mice. However, more detailed analysis revealed fewer proliferative DCX+ cells in the anterior dentate gyrus of male GAP-43+/- mice compared to male +/+ mice. This reduction was not observed in females. These results suggest that young GAP-43+/- mice have decreased hippocampal neurogenesis and synaptic connectivity, but slightly older mice have greater hippocampal neurogenesis and synaptic connectivity. In conjunction with our previous study, these findings suggest that GAP-43 is dynamically involved in early postnatal and adult hippocampal neurogenesis and synaptic connectivity, possibly contributing to the GAP-43+/- behavioral phenotype.
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Affiliation(s)
- Sarah E Latchney
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Tex., USA
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Zikopoulos B, Barbas H. Altered neural connectivity in excitatory and inhibitory cortical circuits in autism. Front Hum Neurosci 2013; 7:609. [PMID: 24098278 PMCID: PMC3784686 DOI: 10.3389/fnhum.2013.00609] [Citation(s) in RCA: 199] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 09/06/2013] [Indexed: 12/12/2022] Open
Abstract
Converging evidence from diverse studies suggests that atypical brain connectivity in autism affects in distinct ways short- and long-range cortical pathways, disrupting neural communication and the balance of excitation and inhibition. This hypothesis is based mostly on functional non-invasive studies that show atypical synchronization and connectivity patterns between cortical areas in children and adults with autism. Indirect methods to study the course and integrity of major brain pathways at low resolution show changes in fractional anisotropy (FA) or diffusivity of the white matter in autism. Findings in post-mortem brains of adults with autism provide evidence of changes in the fine structure of axons below prefrontal cortices, which communicate over short- or long-range pathways with other cortices and subcortical structures. Here we focus on evidence of cellular and axon features that likely underlie the changes in short- and long-range communication in autism. We review recent findings of changes in the shape, thickness, and volume of brain areas, cytoarchitecture, neuronal morphology, cellular elements, and structural and neurochemical features of individual axons in the white matter, where pathology is evident even in gross images. We relate cellular and molecular features to imaging and genetic studies that highlight a variety of polymorphisms and epigenetic factors that primarily affect neurite growth and synapse formation and function in autism. We report preliminary findings of changes in autism in the ratio of distinct types of inhibitory neurons in prefrontal cortex, known to shape network dynamics and the balance of excitation and inhibition. Finally we present a model that synthesizes diverse findings by relating them to developmental events, with a goal to identify common processes that perturb development in autism and affect neural communication, reflected in altered patterns of attention, social interactions, and language.
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Affiliation(s)
- Basilis Zikopoulos
- Neural Systems Laboratory, Department of Health Sciences, Boston University Boston, MA, USA
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Vuillaume ML, Delrue MA, Naudion S, Toutain J, Fergelot P, Arveiler B, Lacombe D, Rooryck C. Expanding the clinical phenotype at the 3q13.31 locus with a new case of microdeletion and first characterization of the reciprocal duplication. Mol Genet Metab 2013; 110:90-7. [PMID: 23920044 DOI: 10.1016/j.ymgme.2013.07.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 07/11/2013] [Accepted: 07/11/2013] [Indexed: 11/30/2022]
Abstract
Congenital deletions at the 3q13.31 locus have been recently described as a novel microdeletion syndrome characterized by developmental delay, postnatal overgrowth, hypoplastic male genitalia and characteristic facial features. A common critical region of overlapping of 580kb was delineated including two strong candidate genes for developmental delay: DRD3 and ZBTB20. In this report, we describe a new case of 3q13.31 microdeletion identified by array-CGH in a 16year-old girl sharing clinical features commonly observed in the 3q13.31 microdeletion syndrome. This girl had a microdeletion of 7.39Mb spanning the common critical region of overlapping. More interestingly, we report for the first time the existence of a microduplication reciprocal to the microdeletion syndrome. This familial 2.76Mb microduplication identified by array-CGH was carried by two brothers and their father. The phenotype shared by the brothers resembled the phenotype related to the 3q13.31 microdeletion syndrome including especially severe intellectual disability, developmental delay, behavioral abnormalities and obesity. This microduplication involves three strong candidate genes for the developmental delay ZBTB20, LSAMP and GAP43. Further molecular characterization showed that DRD3, another strong candidate gene for developmental delay, was not included in the duplicated region. However, a dosage alteration of this gene cannot be completely excluded as the duplication was inverted at proximity of this gene, as revealed by FISH analysis. Finally, we hypothesized that the phenotype shared by the two brothers could be related to a gene dosage imbalance even if gene expression could not be measured in relevant tissues such as brain or adipocytes.
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Affiliation(s)
- Marie-Laure Vuillaume
- CHU Bordeaux, Service de Génétique Médicale, Place Amélie Raba Léon, Bordeaux, France.
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PKC-epsilon activation is required for recognition memory in the rat. Behav Brain Res 2013; 253:280-9. [PMID: 23911427 DOI: 10.1016/j.bbr.2013.07.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 07/18/2013] [Accepted: 07/22/2013] [Indexed: 11/20/2022]
Abstract
Activation of PKCɛ, an abundant and developmentally regulated PKC isoform in the brain, has been implicated in memory throughout life and across species. Yet, direct evidence for a mechanistic role for PKCɛ in memory is still lacking. Hence, we sought to evaluate this in rats, using short-term treatments with two PKCɛ-selective peptides, the inhibitory ɛV1-2 and the activating ψɛRACK, and the novel object recognition task (NORT). Our results show that the PKCɛ-selective activator ψɛRACK, did not have a significant effect on recognition memory. In the short time frames used, however, inhibition of PKCɛ activation with the peptide inhibitor ɛV1-2 significantly impaired recognition memory. Moreover, when we addressed at the molecular level the immediate proximal signalling events of PKCɛ activation in acutely dissected rat hippocampi, we found that ψɛRACK increased in a time-dependent manner phosphorylation of MARCKS and activation of Src, Raf, and finally ERK1/2, whereas ɛV1-2 inhibited all basal activity of this pathway. Taken together, these findings present the first direct evidence that PKCɛ activation is an essential molecular component of recognition memory and point toward the use of systemically administered PKCɛ-regulating peptides as memory study tools and putative therapeutic agents.
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Ansari RW, Shukla RK, Yadav RS, Seth K, Pant AB, Singh D, Agrawal AK, Islam F, Khanna VK. Cholinergic dysfunctions and enhanced oxidative stress in the neurobehavioral toxicity of lambda-cyhalothrin in developing rats. Neurotox Res 2012; 22:292-309. [PMID: 22327935 DOI: 10.1007/s12640-012-9313-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 01/15/2012] [Accepted: 01/19/2012] [Indexed: 01/24/2023]
Abstract
This study is focused on understanding the mechanism of neurobehavioral toxicity of lambda-cyhalothrin, a new generation type II synthetic pyrethroid in developing rats following their exposure from post-lactational day (PLD)22 to PLD49 and investigate whether neurobehavioral alterations are transient or persistent. Post-lactational exposure to lambda-cyhalothrin (1.0 or 3.0 mg/kg body weight, p.o.) affected grip strength and learning activity in rats on PLD50 and the persistent impairment of grip strength and learning was observed at 15 days after withdrawal of exposure on PLD65. A decrease in the binding of muscarinic-cholinergic receptors in frontocortical, hippocampal, and cerebellar membranes associated with decreased expression of choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) in hippocampus was observed following exposure to lambda-cyhalothrin on PLD50 and PLD65. Exposure to lambda-cyhalothrin was also found to increase the expression of growth-associated protein-43 in hippocampus of rats on PLD50 and PLD65 as compared to controls. A significant increase in lipid peroxidation and protein carbonyl levels and decreased levels of reduced glutathione and activity of superoxide dismutase, catalase, and glutathione peroxidase in brain regions of lambda-cyhalothrin exposed rats were distinctly observed indicating increased oxidative stress. Inhibition of ChAT and AChE activity may cause down-regulation of muscarinic-cholinergic receptors consequently impairing learning activity in developing rats exposed to lambda-cyhalothrin. The data further indicate that long-term exposure to lambda-cyhalothrin at low doses may be detrimental and changes in selected behavioral and neurochemical end points may persist if exposure to lambda-cyhalothrin continues.
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Affiliation(s)
- Reyaz W Ansari
- Developmental Toxicology, CSIR-Indian Institute of Toxicology Research, MG Marg, P.O. Box 80, Lucknow 226 001, India
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Liu J, Liu Y, Zou W, Song L, An L. Catalpol Upregulates Hippocampal GAP-43 Level of Aged Rats with Enhanced Spatial Memory and Behavior Response. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/jbbs.2012.24058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Holahan MR, Westby EP, Albert K. Comparison of the MK-801-induced appetitive extinction deficit with pressing for reward and associated pERK1/2 staining in prefrontal cortex and nucleus accumbens. Behav Brain Res 2011; 228:194-202. [PMID: 22182675 DOI: 10.1016/j.bbr.2011.11.044] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 11/18/2011] [Accepted: 11/30/2011] [Indexed: 01/30/2023]
Abstract
Administration of the noncompetitive N-methyl-d-aspartate (NMDA)-receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801) has been shown to produce extinction deficits on appetitive operant tasks. The present study sought to further explore this by comparing extinction pressing to pressing for the primary reward and examining associated neural correlates to determine if the MK-801 extinction profile resembled the behavioral and neural profile associated with pressing for primary reward. Immunohistochemical labeling of phosphorylated extracellular signal-regulated kinase-1 and -2(pERK1/2) in the prelimbic (PrL) and infralimbic (IL) cortices and nucleus accumbens shell (AcbSh) and core (AcbC) was examined after rewarded or extinction lever pressing conditions. A dose-response curve revealed a within-day extinction deficit following administration of 0.05 mg/kg MK-801. All doses of MK-801 were associated with reduced IL pERK1/2 staining but only the 0.05 mg/kg dose was associated with elevated AcbSh pERK1/2 labeling. Extinction pressing under the influence of MK-801 was elevated compared to that seen during rewarded pressing-whether on MK-801 or saline. Rewarded pressing following saline or MK-801 was associated with elevated pERK1/2 in the PrL with no similar patterns in the MK-801/extinction group. There was more pERK1/2 labeling in the AcbSh of the MK-801 extinction group than any other condition. These data suggest that the MK-801-induced extinction deficit may be due to the combination of an underactive cortical behavioral inhibition system and an overactive AcbSh reward system.
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Affiliation(s)
- Matthew R Holahan
- Department of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada.
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Kudryashova IV. Structural and functional modifications of presynaptic afferents: Do they correlate with learning mechanisms? NEUROCHEM J+ 2011. [DOI: 10.1134/s181971241104009x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Holahan MR, Madularu D, McConnell EM, Walsh R, DeRosa MC. Intra-accumbens injection of a dopamine aptamer abates MK-801-induced cognitive dysfunction in a model of schizophrenia. PLoS One 2011; 6:e22239. [PMID: 21779401 PMCID: PMC3135623 DOI: 10.1371/journal.pone.0022239] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 06/16/2011] [Indexed: 11/18/2022] Open
Abstract
Systemic administration of the noncompetitive NMDA-receptor antagonist, MK-801, has been proposed to model cognitive deficits similar to those seen in patients with schizophrenia. The present work investigated the ability of a dopamine-binding DNA aptamer to regulate these MK-801-induced cognitive deficits when injected into the nucleus accumbens. Rats were trained to bar press for chocolate pellet rewards then randomly assigned to receive an intra-accumbens injection of a DNA aptamer (200 nM; n = 7), tris buffer (n = 6) or a randomized DNA oligonucleotide (n = 7). Animals were then treated systemically with MK-801 (0.1 mg/kg) and tested for their ability to extinguish their bar pressing response. Two control groups were also included that did not receive MK-801. Data revealed that injection of Tris buffer or the random oligonucleotide sequence into the nucleus accumbens prior to treatment with MK-801 did not reduce the MK-801-induced extinction deficit. Animals continued to press at a high rate over the entire course of the extinction session. Injection of the dopamine aptamer reversed this MK-801-induced elevation in lever pressing to levels as seen in rats not treated with MK-801. Tests for activity showed that the aptamer did not impair locomotor activity. Results demonstrate the in vivo utility of DNA aptamers as tools to investigate neurobiological processes in preclinical animal models of mental health disease.
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Affiliation(s)
- Matthew R. Holahan
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
- * E-mail: (MRH); (MD)
| | - Dan Madularu
- Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
| | - Erin M. McConnell
- Department of Chemistry, Carleton University, Ottawa, Ontario, Canada
| | - Ryan Walsh
- Department of Chemistry, Carleton University, Ottawa, Ontario, Canada
| | - Maria C. DeRosa
- Department of Chemistry, Carleton University, Ottawa, Ontario, Canada
- * E-mail: (MRH); (MD)
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Maze training in mice induces MRI-detectable brain shape changes specific to the type of learning. Neuroimage 2011; 54:2086-95. [DOI: 10.1016/j.neuroimage.2010.09.086] [Citation(s) in RCA: 253] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 09/04/2010] [Accepted: 09/30/2010] [Indexed: 11/19/2022] Open
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Holahan MR, Clarke MJ, Hines DD. Dopamine-mediated MK-801-induced elevation in food-based extinction responding in rats and associated changes in region-specific phosphorylated ERK. Psychopharmacology (Berl) 2010; 212:393-403. [PMID: 20652538 DOI: 10.1007/s00213-010-1959-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 07/12/2010] [Indexed: 02/03/2023]
Abstract
RATIONALE The current study examined the effect of the noncompetitive N-methyl-D: -aspartate (NMDA) receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801) on the extinction of food-based operant responding. OBJECTIVES Experiments were carried out to determine (1) the nature of the elevated responding when rats were under the influence of MK-801, (2) the effect of combined and separate D1- and D2-like dopaminergic antagonists (SCH 23390 and haloperidol) on this MK-801-induced behavioral effect and (3) the neural correlates on and off MK-801 using immunohistochemical localization of the phosphorylated forms of the extracellular signal-regulated kinase-1 and -2. METHODS Male Long Evans rats were trained using operant conditioning procedures then treated with the various compounds, and resultant extinction pressing was measured. RESULTS A moderate dose (0.1 mg/kg) of MK-801 produced a persistent, elevated lever pressing throughout the entire 30-min extinction session. When animals were pretreated with combined or separate dopamine (DA) D1- or D2-like receptor antagonists, extinction responding under MK-801 was significantly reduced. Examination of pERK1/2 labeling in MK-801-treated animals showed reduced staining in the infralimbic and piriform cortices and elevated staining in the nucleus accumbens compared with controls. CONCLUSIONS These data show that MK-801 elevates food-based extinction behavior that can be reduced by DA receptor antagonists. The disrupted extinction behavior may be mediated, in part, by disinhibition of corticostriatal circuits.
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Affiliation(s)
- Matthew R Holahan
- Department of Psychology, Institute of Neuroscience, Carleton University, 1125 Colonel By Drive, 337 Life Science Research Building, Ottawa, ON, K1S 5B6, Canada.
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Rekart JL, Routtenberg A. Overexpression of GAP-43 reveals unexpected properties of hippocampal mossy fibers. Hippocampus 2010; 20:46-57. [PMID: 19650124 DOI: 10.1002/hipo.20668] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The mossy fiber (MF) system targets the apical dendrites of CA3 pyramidal cells in the stratum lucidum (SL). In mice overexpressing the growth-associated protein GAP-43 there is an apparent ectopic growth of these MFs into the stratum oriens (SO) targeting the basal dendrites of these same pyramidal cells (Aigner et al. (1995) Cell 83:269-278). This is the first evidence to our knowledge that links increased GAP-43 expression with growth of central axons. Here we studied the Aigner et al. transgenic mice but were unable to confirm such growth into SO. However, using quantitative methods we did observe enhanced growth within the regions normally targeted by MFs, for example, the SL in the CA3a region. These contrasting results led us to study MFs with double-immunostaining using an immunohistochemical marker for MFs, the zinc transporter, ZnT3, to visualize the colocalization of transgenic GAP-43 within MFs. Unexpectedly, using both fluorescence and confocal microscopy, we were unable to detect colocalization of GAP-43-positive axons with ZnT3-positive MF axons within the MF pathways, either in the region of the MF axons or in the SL, where MF terminals are abundant. In contrast, the plasma membrane-associated presynaptic marker SNAP-25 did colocalize with transgenic GAP-43-positive terminals in the SL. Synaptophysin, the vesicle-associated presynaptic terminal marker, colocalized with ZnT3 but did not appear to colocalize with GAP-43. The present findings raise important questions about the properties of granule cells and the MF mechanisms that differentially regulate axonal remodeling in the adult hippocampus: (1) Because there appears to be at least two populations of granule cells defined by their differential protein expression, this points to the existence of an intrinsic heterogeneity of granule cell expression beyond that contributed by adult neurogenesis; (2) Giventhe present evidence that growth is induced in mice overexpressing GAP-43 in adjacent non-GAP-43 containing MFs, the potential exists for a heretofore unexplored interaxonal communication mechanism.
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Affiliation(s)
- Jerome L Rekart
- Department of Psychology, Northwestern University, Evanston, IL 60208 USA.
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Holahan MR, Honegger KS, Routtenberg A. Ectopic growth of hippocampal mossy fibers in a mutated GAP-43 transgenic mouse with impaired spatial memory retention. Hippocampus 2010; 20:58-64. [PMID: 19437419 DOI: 10.1002/hipo.20635] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In a previous study, it was shown that transgenic mice, designated G-NonP, forget the location of a water maze hidden platform when tested 7 days after the last training day (Holahan and Routtenberg (2008) Hippocampus 18:1099-1102). The memory loss in G-NonP mice might be related to altered hippocampal architecture suggested by the fact that in the rat, 7 days after water maze training, there is discernible mossy fiber (MF) growth (Holahan et al. (2006) Hippocampus 16:560-570; Rekart et al. (2007) Learn Mem 14:416-421). In the present report, we studied the distribution of the MF system within the hippocampus of naïve, untrained, G-NonP mouse. In WT mice, the MF projection was restricted to the stratum lucidum of CA3 with no detectable MF innervation in distal stratum oriens (dSO). In G-NonP mice, in contrast, there was an ectopic projection terminating in the CA3 dSO. Unexpectedly, there was nearly a complete loss of immunostaining for the axonal marker Tau1 in the G-NonP transgenic mice in the MF terminal fields indicating that transgenesis itself leads to off-target consequences (Routtenberg (1996) Trends Neurosci 19:471-472). Because transgenic mice overexpressing nonmutated, wild type GAP-43 do not show this ectopic growth (Rekart et al., in press) and the G-NonP mice overexpress a mutated form of GAP-43 precluding its phosphorylation by protein kinase C (PKC), the possibility exists that permanently dephosphorylated GAP-43 disrupts normal axonal fasciculation which gives rise to the ectopic growth into dSO.
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Affiliation(s)
- Matthew R Holahan
- Department of Psychology, Institute of Neuroscience, Carleton University, Ottawa, ON K1S 5B6, Canada.
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Proteomic Profiling of Cerebrospinal Fluid by 8-Plex iTRAQ Reveals Potential Biomarker Candidates of Alzheimer’s Disease. Clin Proteomics 2009. [DOI: 10.1007/s12014-009-9030-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Abstract
Introduction
Alzheimer’s disease (AD) poses specific challenges for drug development. It has a slow and variable clinical course, an insidious onset, and symptom expression is only observed when a significant proportion of neurons are already lost.
Discussion
Determinants of clinical course, such as molecular biomarkers, are urgently needed for early detection and diagnosis, or for prognosis and monitoring disease-modifying therapies in stratified patient populations. Due to its proximity to the brain and clinical availability, cerebrospinal fluid (CSF) is likely to have the highest yield of biomarker potential for neurodegenerative diseases. In this study, we examined the feasibility of using of an 8-plex isobaric tagging approach, coupled to two-dimensional liquid chromatography and tandem mass spectrometry using the matrix-assisted laser desorption/ionization time-of-flight/time-of-flight platform, for the discovery of potential biomarker candidates in CSF. Comparative analysis identified a number of statistically significant differences in the level of proteins when comparing AD to nondemented controls. Although the study is statistically underpowered to represent the disease population, the regulation of proteins with involvement in processes such as neuronal loss, synaptic dysfunction, neuroinflammation, and tissue degeneration and remodeling reflects the ability of our method in providing biologically meaningful CSF biomarkers as candidates for larger scale biomarker verification and validation studies.
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Oliveira DR, Sanada PF, Saragossa Filho AC, Innocenti LR, Oler G, Cerutti JM, Cerutti SM. Neuromodulatory property of standardized extract Ginkgo biloba L. (EGb 761) on memory: behavioral and molecular evidence. Brain Res 2009; 1269:68-89. [PMID: 19146837 DOI: 10.1016/j.brainres.2008.11.105] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2008] [Revised: 10/03/2008] [Accepted: 11/14/2008] [Indexed: 11/19/2022]
Abstract
Although it has been suggested that the standardized Ginkgo biloba leaf extract (Egb 761) may have a beneficial effect on memory, the cellular and molecular changes that underlie this process are not yet well defined. The present study evaluated the effects of acute (one dose) or subacute treatments (one daily dose/seven days) with EGb 761 (0.5 g kg(-1) and 1.0 g kg(-1)) on rats submitted to a conditioned emotional response (CER) in comparison with positive (4 mg kg(-1) Diazepam) and negative (12%Tween 80) control groups. To this end, eighty (n=10/group) adult, male, Wistar rats (+/-250-300 g) were used in an off-baseline CER procedure. We here observed that the rats submitted to an acute and subacute EGb 761 treatments had acquisition of fear conditioning. Additionally, we investigate if the expression of genes previously associated with classical conditioning (CREB-1 and GAP-43) and new candidate genes (GFAP) are modulated following EGb 761 acute treatment. CREB-1, GAP-43 and GFAP mRNA and protein expressions were evaluated using both quantitative PCR (qPCR) and immunohistochemical analysis, respectively. We here show, for the first time, that EGb 761 modulated GAP-43, CREB-1 and GFAP expression in the prefrontal cortex, amygdala and hippocampus. We observed an underexpression of GAP-43 in all structures evaluated and over-expression of GFAP in the amygdala and hippocampus following acute G. biloba treatment when compared to control group (Tween; p<0.01). GAP-43 expression was decreased in prefrontal cortex and hippocampus in the subacute treatment with EGb 761. Subacute treatment with EGb 761 lead to a decreased CREB-1 in mPFC (p<0.001) and increased in the hippocampus to 1.0 g kg(-1)G. biloba group (p<0.001). The results obtained from immunohistochemical analysis support our aforementioned findings and revealed that the changes in expression occurred within specific regions in the areas evaluated. All together, our findings not only provide new evidence for a role of EGb 761 on memory but also identify molecular changes that underlie the fear memory consolidation.
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Affiliation(s)
- Daniela R Oliveira
- Department of Biological Science, Federal University of Sao Paulo, SP, Brazil
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Holahan M, Routtenberg A. The protein kinase C phosphorylation site on GAP-43 differentially regulates information storage. Hippocampus 2009; 18:1099-102. [PMID: 18727047 DOI: 10.1002/hipo.20486] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Protein kinase C (PKC) is known to regulate phosphorylation of substrates such as MARCKS, GAP-43, and the NMDA receptor, all of which have been linked to synaptic plasticity underlying information storage processes. Here we report on three transgenic mice isoforms differentiated both by mutation of the PKC site on GAP-43 as well as by their performance in three learning situations: (1) a radial arm maze task, which evaluates spatial memory and its retention, (2) fear conditioning which assesses contextual memory, and (3) the water maze which also evaluates spatial memory and its retention. The present results show, for the first time to our knowledge, that the phosphorylation state of a single site on an identified brain growth- and plasticity-associated protein differentially regulates performance of three different memory-associated tasks.
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Affiliation(s)
- Matthew Holahan
- Department of Psychology and Institute of Neuroscience, Carleton University, Ottawa, Canada.
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Abstract
Most molecular and cellular studies of cognitive function have focused on either normal or pathological states, but recent research with transgenic mice has started to address the mechanisms of enhanced cognition. These results point to key synaptic and nuclear signalling events that can be manipulated to facilitate the induction or increase the stability of synaptic plasticity, and therefore enhance the acquisition or retention of information. Here, we review these surprising findings and explore their implications to both mechanisms of learning and memory and to ongoing efforts to develop treatments for cognitive disorders. These findings represent the beginning of a fundamental new approach in the study of enhanced cognition.
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Affiliation(s)
- Yong-Seok Lee
- Department of Neurobiology, Brain Research Institute, University of California, Los Angeles, California 90095, USA
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Tanner DC, Qiu S, Bolognani F, Partridge LD, Weeber EJ, Perrone-Bizzozero NI. Alterations in mossy fiber physiology and GAP-43 expression and function in transgenic mice overexpressing HuD. Hippocampus 2008; 18:814-23. [PMID: 18493953 DOI: 10.1002/hipo.20442] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
HuD is a neuronal RNA-binding protein associated with the stabilization of mRNAs for GAP-43 and other neuronal proteins that are important for nervous system development and learning and memory mechanisms. To better understand the function of this protein, we generated transgenic mice expressing human HuD (HuD-Tg) in adult forebrain neurons. We have previously shown that expression of HuD in adult dentate granule cells results in an abnormal accumulation of GAP-43 mRNA via posttranscriptional mechanisms. Here we show that this mRNA accumulation leads to the ectopic expression of GAP-43 protein in mossy fibers. Electrophysiological analyses of the mossy fiber to CA3 synapse of HuD-Tg mice revealed increases in paired-pulse facilitation (PPF) at short interpulse intervals and no change in long-term potentiation (LTP). Presynaptic calcium transients at the same synapses exhibited faster time constants of decay, suggesting a decrease in the endogenous Ca(2+) buffer capacity of mossy fiber terminals of HuD-Tg mice. Under resting conditions, GAP-43 binds very tightly to calmodulin sequestering it and then releasing it upon PKC-dependent phosphorylation. Therefore, subsequent studies examined the extent of GAP-43 phosphorylation and its association to calmodulin. We found that despite the increased GAP-43 expression in HuD-Tg mice, the levels of PKC-phosphorylated GAP-43 were decreased in these animals. Furthermore, in agreement with the increased proportion of nonphosphorylated GAP-43, HuD-Tg mice showed increased binding of calmodulin to this protein. These results suggest that a significant amount of calmodulin may be trapped in an inactive state, unable to bind free calcium, and activate downstream signaling pathways. In conclusion, we propose that an unregulated expression of HuD disrupts mossy fiber physiology in adult mice in part by altering the expression and phosphorylation of GAP-43 and the amount of free calmodulin available at the synaptic terminal.
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Affiliation(s)
- Daniel C Tanner
- Department of Neurosciences, University of New Mexico HSC, Albuquerque, New Mexico 87106, USA
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A crosslinking analysis of GAP-43 interactions with other proteins in differentiated N1E-115 cells. Int J Mol Sci 2008; 9:1753-1771. [PMID: 19325830 PMCID: PMC2635752 DOI: 10.3390/ijms9091753] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 09/03/2008] [Accepted: 09/13/2008] [Indexed: 11/16/2022] Open
Abstract
It has been suggested that GAP-43 (growth-associated protein) binds to various proteins in growing neurons as part of its mechanism of action. To test this hypothesis in vivo, differentiated N1E-115 neuroblastoma cells were labeled with [35S]-amino acids and were treated with a cleavable crosslinking reagent. The cells were lysed in detergent and the lysates were centrifuged at 100,000 × g to isolate crosslinked complexes. Following cleavage of the crosslinks and analysis by two-dimensional gel electrophoresis, it was found that the crosslinker increased the level of various proteins, and particularly actin, in this pellet fraction. However, GAP-43 was not present, suggesting that GAP-43 was not extensively crosslinked to proteins of the cytoskeleton and membrane skeleton and did not sediment with them. GAP-43 also did not sediment with the membrane skeleton following nonionic detergent lysis. Calmodulin, but not actin or other proposed interaction partners, co-immunoprecipitated with GAP-43 from the 100,000 × g supernatant following crosslinker addition to cells or cell lysates. Faint spots at 34 kDa and 60 kDa were also present. Additional GAP-43 was recovered from GAP-43 immunoprecipitation supernatants with anti-calmodulin but not with anti-actin. The results suggest that GAP-43 is not present in complexes with actin or other membrane skeletal or cytoskeletal proteins in these cells, but it is nevertheless possible that a small fraction of the total GAP-43 may interact with other proteins.
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Korshunova I, Mosevitsky M. Role of the Growth-associated Protein GAP-43 in NCAM-mediated Neurite Outgrowth. Neurochem Res 2008. [DOI: 10.1007/s11064-008-9800-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Routtenberg A. The substrate for long-lasting memory: if not protein synthesis, then what? Neurobiol Learn Mem 2007; 89:225-33. [PMID: 18162421 DOI: 10.1016/j.nlm.2007.10.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 10/29/2007] [Accepted: 10/29/2007] [Indexed: 01/20/2023]
Abstract
The prevailing textbook view that de novo protein synthesis is required for memory (e.g., [Bear, M. F., Connors, B., & Paradiso, M. 2006. Neuroscience. Lippincott, New York]) is seriously flawed and an alternative hypothesis has been proposed in which post-translational modification (PTM) of proteins already synthesized and already present within the synapse is 'the' substrate for long-lasting memory. Protein synthesis serves a replenishment role. The first part of this review discusses how long-lasting memory can be achieved with 'only' PTM of existing synaptic proteins. The second part critically reviews a recent report published in Neuron 2007 that exemplifies the current view of protein synthesis and memory while also illustrating how these results can be understood within this new PTM framework. A necessary yet unexpected conclusion to emerge from consideration of the consequences of a PTM mechanism as the necessary, sufficient and exclusive substrate for long-lasting memory, is that the central Hebbian dogma that cells that 'fire together, wire together' is an unlikely mechanism for long-lasting memory. Thus, a unique feature of the PTM model is that longevity of information storage is achieved not by stability of the synaptic mechanism, but by impermanent pseudoredundant circuits. This is so because PTM is a reversible process and thus any permanent connection, any 'lasting effect' cannot be in the form of stable synapse formation. We have therefore proposed a solution in which network level processes regulate cellular mechanisms, even as such mechanisms regulate the network. Thus, synapses are 'meta-stabilized' by regulated feedback mediated by the circuit in which the synapse is embedded. For example, spontaneous activity is proposed to be a substrate feedback mechanism we term 'cryptic rehearsal' to sustain for some period of time after learning an approximation to the state initially created by input. Additionally, because the duplication of these traces is ongoing, this provides a degenerate code for the engram. Stability is thus achieved, not by stabilizing the synapse, but by implementing a pseudo-redundant yet malleable circuitry so that memory can be protected in the face of small catastrophes in network representation.
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Affiliation(s)
- Aryeh Routtenberg
- Department of Psychology, Northwestern University, Evanston IL 60208, USA.
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