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Canet G, Zussy C, Hernandez C, Maurice T, Desrumaux C, Givalois L. The pathomimetic oAβ25–35 model of Alzheimer's disease: Potential for screening of new therapeutic agents. Pharmacol Ther 2023; 245:108398. [PMID: 37001735 DOI: 10.1016/j.pharmthera.2023.108398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 03/27/2023] [Indexed: 03/31/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia in the elderly, currently affecting more than 40 million people worldwide. The two main histopathological hallmarks of AD were identified in the 1980s: senile plaques (composed of aggregated amyloid-β (Aβ) peptides) and neurofibrillary tangles (composed of hyperphosphorylated tau protein). In the human brain, both Aβ and tau show aggregation into soluble and insoluble oligomers. Soluble oligomers of Aβ include their most predominant forms - Aβ1-40 and Aβ1-42 - as well as shorter peptides such as Aβ25-35 or Aβ25-35/40. Most animal models of AD have been developed using transgenesis, based on identified human mutations. However, these familial forms of AD represent less than 1% of AD cases. In this context, the idea emerged in the 1990s to directly inject the Aβ25-35 fragment into the rodent brain to develop an acute model of AD that could mimic the disease's sporadic forms (99% of all cases). This review aims to: (1) summarize the biological activity of Aβ25-35, focusing on its impact on the main structural and functional alterations observed in AD (cognitive deficits, APP misprocessing, tau system dysfunction, neuroinflammation, oxidative stress, cholinergic and glutamatergic alterations, HPA axis dysregulation, synaptic deficits and cell death); and (2) confirm the interest of this pathomimetic model in AD research, as it has helped identify and characterize many molecules (marketed, in clinical development, and in preclinical testing), and to the development of alternative approaches for AD prevention and therapy. Today, the Aβ25-35 model appears as a first-intent choice model to rapidly screen the symptomatic or neuroprotective potencies of new compounds, chemical series, or innovative therapeutic strategies.
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Aghajanov M, Matinyan S, Chavushyan V, Danielyan M, Karapetyan G, Mirumyan M, Fereshetyan K, Harutyunyan H, Yenkoyan K. The Involvement of Insulin-Like Growth Factor 1 and Nerve Growth Factor in Alzheimer's Disease-Like Pathology and Survival Role of the Mix of Embryonic Proteoglycans: Electrophysiological Fingerprint, Structural Changes and Regulatory Effects on Neurotrophins. Int J Mol Sci 2021; 22:ijms22137084. [PMID: 34209299 PMCID: PMC8267974 DOI: 10.3390/ijms22137084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/17/2021] [Accepted: 06/28/2021] [Indexed: 12/31/2022] Open
Abstract
Alzheimer’s disease (AD)-associated neurodegeneration is triggered by different fragments of amyloid beta (Aβ). Among them, Aβ (25–35) fragment plays a critical role in the development of neurodegeneration—it reduces synaptic integrity by disruption of excitatory/inhibitory ratio across networks and alters the growth factors synthesis. Thus, in this study, we aimed to identify the involvement of neurotrophic factors—the insulin-like growth factor 1 (IGF-1) and nerve growth factor (NGF)—of AD-like neurodegeneration induced by Aβ (25–35). Taking into account our previous findings on the neuroprotective effects of the mix of proteoglycans of embryonic genesis (PEG), it was suggested to test its regulatory effect on IGF-1 and NGF levels. To evaluate the progress of neurodegeneration, in vivo electrophysiological investigation of synaptic activity disruption of the entorhinal cortex–hippocampus circuit at AD was performed and the potential recovery effects of PEG with relative structural changes were provided. To reveal the direct effects of PEG on brain functional activity, the electrophysiological pattern of the single cells from nucleus supraopticus, sensomotor cortex and hippocampus after acute injection of PEG was examined. Our results demonstrated that after i.c.v. injection of Aβ (25–35), the level of NGF decreased in cerebral cortex and hypothalamus, and, in contrast, increased in hippocampus, prompting its multidirectional role in case of brain damage. The concentration of IGF-1 significantly increased in all investigated brain structures. The administration of PEG balanced the growth factor levels accompanied by substantial restoration of neural tissue architecture and synaptic activity. Acute injection of PEG activated the hypothalamic nucleus supraopticus and hippocampal neurons. IGF-1 and NGF levels were found to be elevated in animals receiving PEG in an absence of amyloid exposure. We suggest that IGF-1 and NGF play a critical role in the development of AD. At the same time, it becomes clear that the neuroprotective effects of PEG are likely mediated via the regulation of neurotrophins.
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Affiliation(s)
- Michail Aghajanov
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (M.A.); (S.M.); (M.M.); (K.F.)
| | - Senik Matinyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (M.A.); (S.M.); (M.M.); (K.F.)
- Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (V.C.); (M.D.); (G.K.); (H.H.)
| | - Vergine Chavushyan
- Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (V.C.); (M.D.); (G.K.); (H.H.)
- Laboratory of Neuroendocrine Relations, L. Orbeli Institute of Physiology of NAS, Yerevan 0028, Armenia
| | - Margarita Danielyan
- Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (V.C.); (M.D.); (G.K.); (H.H.)
- Laboratory of Histochemistry and Electromicroscopy, L. Orbeli Institute of Physiology of NAS, Yerevan 0028, Armenia
| | - Gohar Karapetyan
- Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (V.C.); (M.D.); (G.K.); (H.H.)
| | - Margarita Mirumyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (M.A.); (S.M.); (M.M.); (K.F.)
- Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (V.C.); (M.D.); (G.K.); (H.H.)
| | - Katarine Fereshetyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (M.A.); (S.M.); (M.M.); (K.F.)
- Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (V.C.); (M.D.); (G.K.); (H.H.)
| | - Hayk Harutyunyan
- Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (V.C.); (M.D.); (G.K.); (H.H.)
| | - Konstantin Yenkoyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (M.A.); (S.M.); (M.M.); (K.F.)
- Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan 0025, Armenia; (V.C.); (M.D.); (G.K.); (H.H.)
- Correspondence: or
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Lee AY, Choi JM, Lee YA, Shin SH, Cho EJ. Beneficial effect of black rice ( Oryza sativa L. var. japonica ) extract on amyloid β-induced cognitive dysfunction in a mouse model. Exp Ther Med 2020; 20:64. [PMID: 32963594 DOI: 10.3892/etm.2020.9192] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 05/29/2020] [Indexed: 12/29/2022] Open
Abstract
Alzheimer's disease (AD) is an age-dependent progressive neurodegenerative disease, resulting in memory loss and cognitive dysfunction. The accumulation of amyloid β (Aβ) has been identified as the most important risk factor for AD. Black rice (BR; Oryza sativa L. var. japonica), which is widely consumed in Asia, is a good source of bioactive compounds including anthocyanins. Therefore, the aim of the present study was to evaluate the protective effect of BR extracts against Aβ25-35-induced memory impairment in an in vivo AD mouse model. After intracerebroventricular injection of Aβ25-35, mice were treated with BR extract supplementation for 14 days. Memory and cognition function were evaluated over this period in both treated and untreated animals using T-maze, novel object recognition and Morris water maze tests. After behavioral tests, malondialdehyde (MDA) and nitric oxide (NO) concentrations in brain, liver and kidney tissues were analyzed. Mice treated with Aβ25-35 had impaired memory and cognitive function; however, mice administered BR extract (100 mg/kg/day) demonstrated an improvement in cognition and memory function compared with the Aβ25-35-injected control group. Furthermore, injection of Aβ25-35 significantly increased MDA and NO generation in the brain, liver and kidney of mice. However, the group administered with BR extract had significantly inhibited lipid peroxidation and NO generation in the brain, liver and kidney. In addition, the protective effect of BR on lipid peroxidation and NO production by Aβ25-35 was stronger in the brain compared with other tissues. Collectively, these findings suggested that BR supplementation may prevent memory and cognition deficits caused by Aβ25-35-induced oxidative stress.
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Affiliation(s)
- Ah Young Lee
- Department of Food Science, Gyeongnam National University of Science and Technology, Jinju 52725, Republic of Korea
| | - Ji Myung Choi
- Department of Food Science and Nutrition, Research Institute of Ecology, Pusan National University, Busan 46241, Republic of Korea
| | - Young A Lee
- Department of Food Science and Nutrition, Catholic University of Daegu, Gyeongsan 38430, Republic of Korea
| | - Seon Hwa Shin
- Department of Food Science and Nutrition, Research Institute of Ecology, Pusan National University, Busan 46241, Republic of Korea
| | - Eun Ju Cho
- Department of Food Science and Nutrition, Research Institute of Ecology, Pusan National University, Busan 46241, Republic of Korea
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Embryonic proteoglycans regulate monoamines in the rat frontal cortex and hippocampus in Alzheimer's disease-like pathology. Neurochem Int 2020; 140:104838. [PMID: 32853753 DOI: 10.1016/j.neuint.2020.104838] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 08/05/2020] [Accepted: 08/14/2020] [Indexed: 11/20/2022]
Abstract
Using the rat Alzheimer's disease (AD)-like model we have analyzed the hippocampal short-term potentiation, levels of monoamines, and morphological changes in the hippocampal and cortical neurons after the administration of proteoglycans of embryonic origin (PEG). Results showed that the levels of monoamines and especially norepinephrine in the target AD brain structures were found elevated, except serotonin, which was unaffected in the hippocampus, but decreased in the frontal cortex. These changes were accompanied by the substantial structural damage of cortical and hippocampal neurons. PEG was able to reverse most of these changes. In addition, PEG administration had regime-dependent effects on a short-term potentiation pattern of hippocampal neurons. The elevated levels of key elements of brain monoaminergic system in the model of AD support the hypothesis of the important role of monoamines in the excessive synaptic excitation resulting in cognitive dysfunction in AD brain. The neuroprotective effect of PEG, as manifested by the recovery of the monoaminergic system, suggests this bioactive substance as a perspective therapeutic agent for the treatment of AD.
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Ozawa T, Yamada K, Ichitani Y. d-Cycloserine reverses scopolamine-induced object and place memory deficits in a spontaneous recognition paradigm in rats. Pharmacol Biochem Behav 2019; 187:172798. [PMID: 31678790 DOI: 10.1016/j.pbb.2019.172798] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 09/02/2019] [Accepted: 10/08/2019] [Indexed: 11/26/2022]
Abstract
d-Cycloserine (DCS) is a partial agonist of the glutamatergic N-methyl-d-aspartate (NMDA) receptor-associated glycine site, and it prevents the amnesic effects of the muscarinic receptor antagonist scopolamine in various memory tests in rodents. In the present study, we tested the hypothesis that DCS has anti-amnesic effects in scopolamine-induced deficits using spontaneous object recognition and place recognition tests. In both tests, scopolamine (0.5 mg/kg, i.p.) was systemically administered 60 min prior to testing, while DCS (7.5, 15, 30 mg/kg, i.p.) was administered 30 min before testing, which consisted of a sample phase (5 min), a delay interval (15 min) and a test phase (2 min). DCS treatment reversed scopolamine-induced deficits in discriminatory behavior during the test phase. However, DCS did not affect decreased object exploration itself or increased thigmotaxis in the open-field arena induced by scopolamine. These results support our hypothesis and suggest differential contributions of glutamatergic-cholinergic system interactions to recognition memory and non-mnemonic exploratory behaviors.
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Affiliation(s)
- Takaaki Ozawa
- Institute of Psychology and Behavioral Neuroscience, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Kazuo Yamada
- Institute of Psychology and Behavioral Neuroscience, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Yukio Ichitani
- Institute of Psychology and Behavioral Neuroscience, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan.
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Aghajanov M, Chavushyan V, Matinyan S, Danielyan M, Yenkoyan K. Alzheimer's disease-like pathology-triggered oxidative stress, alterations in monoamines levels, and structural damage of locus coeruleus neurons are partially recovered by a mix of proteoglycans of embryonic genesis. Neurochem Int 2019; 131:104531. [PMID: 31425747 DOI: 10.1016/j.neuint.2019.104531] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/12/2019] [Accepted: 08/13/2019] [Indexed: 12/15/2022]
Abstract
Alzheimer's disease (AD) pathogenesis includes oxidative damage and perturbations of monoamines. However, as many details of these alterations are not known, we have investigated the changes in monoamine levels as well as the free radical oxidation processes (FRO) in the brainstem of rats that were administered i.c.v. Aβ (25-35) (rat model of AD-like pathology). The level of oxidative stress was found elevated in the brainstem along with the increased concentrations of monoamines, especially norepinephrine in the locus coeruleus (LC) area of the brainstem. This was accompanied by the substantial structural damage of monoaminergic neurons of LC. In addition, we have tested the ability of proteoglycans of embryonic genesis (PEG) that were shown previously to act as neuroprotectors, to restore the AD-triggered alterations in monoaminergic system and FRO. Indeed, PEG reduced the increased FRO and upregulated monoamines in the brainstem of Aβ (25-35) treated animals. Administration of PEG to control animals led to the increase of the antioxidant capacity as well as the intensity of free radical oxidation processes. Our study confirms the important role of the brainstem FRO and monoamine shifts in AD development along with the known aggregation of Ab peptide and Tau hyperphosphorylation. We suggest that at the early stages of AD development, with still functional neurons, regulation of monoamine levels via stabilizing FRO processes can be beneficial. Our data demonstrate the regulatory action of PEG on the monoamine disturbances and the level of oxidative stress in the AD damaged structures, suggesting its possible therapeutic application in AD.
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Affiliation(s)
- Michail Aghajanov
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia
| | - Vergine Chavushyan
- Laboratory of Neuroendocrine Relations, L. Orbeli Institute of Physiology of NAS, Yerevan, Armenia
| | - Senik Matinyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia; Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia
| | - Margarita Danielyan
- Laboratory of Histochemistry and Electromicroscopy, L. Orbeli Institute of Physiology of NAS, Yerevan, Armenia
| | - Konstantin Yenkoyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia; Laboratory of Neuroscience, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia.
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Yenkoyan K, Fereshetyan K, Matinyan S, Chavushyan V, Aghajanov M. The role of monoamines in the development of Alzheimer's disease and neuroprotective effect of a proline rich polypeptide. Prog Neuropsychopharmacol Biol Psychiatry 2018; 86:76-82. [PMID: 29782957 DOI: 10.1016/j.pnpbp.2018.05.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 05/12/2018] [Accepted: 05/17/2018] [Indexed: 11/26/2022]
Abstract
INTRODUCTION We have analyzed the alterations in the brain monoaminergic system using the rat model of AD-like pathology. In addition, we have investigated potential neuroprotective effects of the hypothalamic proline-rich polypeptide (PRP-1). METHODS Histochemical staining, HPLC, chemiluminescent and bioluminescence assays. RESULTS The levels of monoamines in the target AD brain structures were found elevated, except serotonin, which was unaffected in both hippocampus and brainstem and decreased in frontal cortex. This was accompanied by the substantial structural damage of cortical, hippocampal, as well as the monoaminergic neurons of locus coeruleus and oxidative stress. PRP-1 was able to reverse most of these changes. DISCUSSION The increased levels of major brain monoamines in the model of AD supports the hypothesis of the important role of monoamines in the excessive synaptic excitation resulting in cognitive dysfunction in AD brain. The neuroprotective effect of PRP-1 as manifested by the recovery of monoaminergic system suggests this bioactive compound as a perspective therapeutic agent for the treatment of AD.
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Affiliation(s)
- Konstantin Yenkoyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia; Laboratory of Biochemical and Biophysical Investigations, Scientific-Research Centre, Yerevan State Medical University after Mkhitar Heratsi, Yerevan, Armenia.
| | - Katarine Fereshetyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia
| | - Senik Matinyan
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia
| | - Vergine Chavushyan
- Laboratory of Neuroendocrine Relations, L. Orbeli Institute of Physiology of NAS, Yerevan, Armenia; Laboratory of Biochemical and Biophysical Investigations, Scientific-Research Centre, Yerevan State Medical University after Mkhitar Heratsi, Yerevan, Armenia
| | - Michail Aghajanov
- Department of Biochemistry, Yerevan State Medical University after M. Heratsi, Yerevan, Armenia
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Neuroprotective Effects of Macrovipera lebetina Snake Venom in the Model of Alzheimer’s Disease. NEUROPHYSIOLOGY+ 2018. [DOI: 10.1007/s11062-018-9704-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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The Protective Effects of IGF-I against β-Amyloid-related Downregulation of Hippocampal Somatostatinergic System Involve Activation of Akt and Protein Kinase A. Neuroscience 2018; 374:104-118. [PMID: 29406271 DOI: 10.1016/j.neuroscience.2018.01.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 12/14/2017] [Accepted: 01/18/2018] [Indexed: 12/13/2022]
Abstract
Somatostatin (SRIF), a neuropeptide highly distributed in the hippocampus and involved in learning and memory, is markedly reduced in the brain of Alzheimer's disease patients. The effects of insulin-like growth factor-I (IGF-I) against β amyloid (Aβ)-induced neuronal death and associated cognitive disorders have been extensively reported in experimental models of this disease. Here, we examined the effect of IGF-I on the hippocampal somatostatinergic system in Aβ-treated rats and the molecular mechanisms associated with changes in this peptidergic system. Intracerebroventricular Aβ25-35 administration during 14 days (300 pmol/day) to male rats increased Aβ25-35 levels and cell death and markedly reduced SRIF and SRIF receptor 2 levels in the hippocampus. These deleterious effects were associated with reduced Akt and cAMP response element-binding protein (CREB) phosphorylation and activation of c-Jun N-terminal kinase (JNK). Subcutaneous IGF-I co-administration (50 µg/kg/day) reduced hippocampal Aβ25-35 levels, cell death and JNK activation. In addition, IGF-I prevented the reduction in the components of the somatostatinergic system affected by Aβ infusion. Its co-administration also augmented protein kinase A (PKA) activity, as well as Akt and CREB phosphorylation. These results suggest that IGF-I co-administration may have protective effects on the hippocampal somatostatinergic system against Aβ insult through up-regulation of PKA activity and Akt and CREB phosphorylation.
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Sun SW, Nishioka C, Labib W, Liang HF. Axonal Terminals Exposed to Amyloid-β May Not Lead to Pre-Synaptic Axonal Damage. J Alzheimers Dis 2016; 45:1139-48. [PMID: 25697704 DOI: 10.3233/jad-142154] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND Synaptic deficits and neuronal loss are the major pathological manifestations of Alzheimer's disease. However, the link between the early synaptic loss and subsequent neurodegeneration is not entirely clear. Cell culture studies have shown that amyloid-β (Aβ) applied to axonal terminals can cause retrograde degeneration leading to the neuronal loss, but this process has not been demonstrated in live animals. OBJECTIVE To test if Aβ applied to retinal ganglion cell axonal terminals can induce axonal damage in the optic nerve and optic tract in mice. METHODS Aβ was injected into the terminal field of the optic tract, in the left lateral geniculate nucleus of wildtype C57BL/6 mice. Following the injection, monthly diffusion tensor imaging was performed. Three months after the injection, mice underwent visual evoked potential recordings, and then sacrificed for immunohistochemical examination. RESULTS There were no significant changes seen with diffusion tensor imaging in the optic nerve and optic tract 3 months after the Aβ injection. The myelin and axons in these regions remained intact according to immunohistochemistry. The only significant changes observed in this study were delayed transduction and reduced amplitude of visual evoked potentials, although both Aβ and its reversed form caused similar changes. CONCLUSION Despite the published in vitro studies, there was no significant axonal damage in the optic nerve and optic tract after injecting Aβ onto retinal ganglion cell axonal terminals of wildtype C57BL/6 mice.
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Affiliation(s)
- Shu-Wei Sun
- Basic Sciences, Schools of Medicine, Loma Linda University, Loma Linda, CA, USA Radiation Medicine, Schools of Medicine, Loma Linda University, Loma Linda, CA, USA Pharmaceutical Science, School of Pharmacy, Loma Linda University, Loma Linda, CA, USA Neuroscience, University of California in Riverside, Riverside, CA, USA Bioengineering, University of California in Riverside, Riverside, CA, USA
| | | | - Wessam Labib
- Family Medicine, Loma Linda University Medical Center, Loma Linda, CA, USA
| | - Hsiao-Fang Liang
- Basic Sciences, Schools of Medicine, Loma Linda University, Loma Linda, CA, USA
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Lack of synaptic vesicle protein SV2B protects against amyloid-β25–35-induced oxidative stress, cholinergic deficit and cognitive impairment in mice. Behav Brain Res 2014; 271:277-85. [DOI: 10.1016/j.bbr.2014.06.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 06/06/2014] [Accepted: 06/08/2014] [Indexed: 11/22/2022]
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Sun SW, Liang HF, Mei J, Xu D, Shi WX. In vivo diffusion tensor imaging of amyloid-β-induced white matter damage in mice. J Alzheimers Dis 2014; 38:93-101. [PMID: 24077431 DOI: 10.3233/jad-130236] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Diffusion tensor imaging (DTI) suggests the presence of white matter abnormality at the prodromal stage in human Alzheimer's disease (AD). OBJECTIVE To use a mouse model of AD to determine whether the white matter abnormality detected by in vivo DTI is associated with functional deficits and axon damage. METHODS Amyloid-β1-42 (Aβ1-42) was injected into the left lateral ventricle in mice. Two months after the injection, in vivo DTI and visual evoked potential (VEP) recordings were performed, followed by immunohistochemistry of phosphorylated neurofilament and myelin basic protein. RESULTS DTI of Aβ1-42-treated mice showed a significant increase of radial diffusivity in white matter including the optic nerves and tracts. The abnormality was associated with decreased amplitude and increased latency of VEP. Immunohistochemistry confirmed a significant loss of axons and myelin integrity. CONCLUSION White matter damage induced by Aβ1-42 in mice can be detected non-invasively by DTI.
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Affiliation(s)
- Shu-Wei Sun
- Basic Science, School of Medicine, Loma Linda University, CA, USA Radiation Medicine, School of Medicine, School of Pharmacy, Loma Linda University, CA, USA Pharmaceutical Science, School of Pharmacy, Loma Linda University, CA, USA Bioengineering, University of California, Riverside, CA, USA
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Detrait ER, Danis B, Lamberty Y, Foerch P. Peripheral administration of an anti-TNF-α receptor fusion protein counteracts the amyloid induced elevation of hippocampal TNF-α levels and memory deficits in mice. Neurochem Int 2014; 72:10-3. [PMID: 24726770 DOI: 10.1016/j.neuint.2014.04.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 03/12/2014] [Accepted: 04/03/2014] [Indexed: 12/24/2022]
Abstract
Alzheimer's disease has long been associated with increased inflammation in the brain. Activated microglia and increased production of the inflammatory cytokines such as TNF-α, have been proposed to contribute to the onset and progression of the disease. We investigated if systemic administration of an anti-tumor necrosis factor (TNF) biologic medication clinically validated for rheumatoid arthritis (RA), TNF receptor 2 fused to a Fc domain (TNFR2:Fc), could ameliorate the behavioral symptoms and decrease neuroinflammation in a non-transgenic mouse model mimicking some hallmarks of the disease. Seven days after a single intracebroventricular (icv) injection of aggregated amyloid beta25-35 (9nmoles), mice displayed significant cognitive deficit in spontaneous alternation (working memory) and inhibitory avoidance (long-term memory) tasks. Alternation percentage decreased from 72.4%±1.3 to chance level (52.6%±1.7); step-through retention latency decreased from 247s to 144s. Subcutaneous administration of 30mg/kg TNFR2:Fc every second day post amyloid beta25-35 icv administration counteracted the amyloid-induced decrease in alternation percentage (66.4s±1.8) and the decreased step-through retention latency (248s±9). Measurement of hippocampal TNF-α levels by ELISA after behavioral assessment showed significant elevation in animals injected with amyloid beta25-35 relative to animals injected with control peptide. In animals treated with 30mg/kg TNFR2:Fc, TNF-α levels in the hippocampus were reduced and were similar to control animals. These data suggest that peripheral administration of TNFR2:Fc counteracts amyloid-induced memory impairment and normalizes increased TNF-α levels in hippocampus of a non-transgenic mouse model of amyloid induced cognitive deficit.
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Affiliation(s)
- E R Detrait
- UCB S.A., CNS Research, Chemin du Foriest, B-1420 Braine-l'Alleud, Belgium.
| | - B Danis
- UCB S.A., CNS Research, Chemin du Foriest, B-1420 Braine-l'Alleud, Belgium
| | - Y Lamberty
- UCB S.A., CNS Research, Chemin du Foriest, B-1420 Braine-l'Alleud, Belgium
| | - P Foerch
- UCB S.A., CNS Research, Chemin du Foriest, B-1420 Braine-l'Alleud, Belgium
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Aghajanov MI, Yenkoyan KB, Chavushyan VA, Sarkissian JS. The proline-rich hypothalamic peptide is a modulator of functions of neurotrophins and neuronal activity in amyloid-induced neurodegeneration. NEUROCHEM J+ 2014. [DOI: 10.1134/s1819712414010036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Campolongo P, Ratano P, Ciotti MT, Florenzano F, Nori SL, Marolda R, Palmery M, Rinaldi AM, Zona C, Possenti R, Calissano P, Severini C. Systemic administration of substance P recovers beta amyloid-induced cognitive deficits in rat: involvement of Kv potassium channels. PLoS One 2013; 8:e78036. [PMID: 24265678 PMCID: PMC3827079 DOI: 10.1371/journal.pone.0078036] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 09/16/2013] [Indexed: 11/18/2022] Open
Abstract
Reduced levels of Substance P (SP), an endogenous neuropeptide endowed with neuroprotective and anti-apoptotic properties, have been found in brain and spinal fluid of Alzheimer's disease (AD) patients. Potassium (K(+)) channel dysfunction is implicated in AD development and the amyloid-β (Aβ)-induced up-regulation of voltage-gated potassium channel subunits could be considered a significant step in Aβ brain toxicity. The aim of this study was to evaluate whether SP could reduce, in vivo, Aβ-induced overexpression of Kv subunits. Rats were intracerebroventricularly infused with amyloid-β 25-35 (Aβ25-35, 20 µg) peptide. SP (50 µg/Kg, i.p.) was daily administered, for 7 days starting from the day of the surgery. Here we demonstrate that the Aβ infused rats showed impairment in cognitive performances in the Morris water maze task 4 weeks after Aβ25-35 infusion and that this impairing effect was prevented by SP administration. Kv1.4, Kv2.1 and Kv4.2 subunit levels were quantified in hippocampus and in cerebral cortex by Western blot analysis and immunofluorescence. Interestingly, SP reduced Kv1.4 levels overexpressed by Aβ, both in hippocampus and cerebral cortex. Our findings provide in vivo evidence for a neuroprotective activity of systemic administration of SP in a rat model of AD and suggest a possible mechanism underlying this effect.
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Affiliation(s)
- Patrizia Campolongo
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Patrizia Ratano
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | | | - Fulvio Florenzano
- Institute of Cell Biology and Neurobiology, CNR, Rome, Italy
- European Brain Research Institute, Rome, Italy
| | - Stefania Lucia Nori
- Department of Medicine and Surgery, University of Salerno Medicine Campus, Baronissi (SA), Italy
| | - Roberta Marolda
- Institute of Cell Biology and Neurobiology, CNR, Rome, Italy
| | - Maura Palmery
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Anna Maria Rinaldi
- Department of Neuroscience, University of Rome “Tor Vergata”, Rome, Italy
| | - Cristina Zona
- Department of Neuroscience, University of Rome “Tor Vergata”, Rome, Italy
- IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Roberta Possenti
- Department of Neuroscience, University of Rome “Tor Vergata”, Rome, Italy
| | | | - Cinzia Severini
- Institute of Cell Biology and Neurobiology, CNR, Rome, Italy
- * E-mail:
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16
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Wang ZJ, Han WN, Yang GZ, Yuan L, Liu XJ, Li QS, Qi JS. The neuroprotection of Rattin against amyloid β peptide in spatial memory and synaptic plasticity of rats. Hippocampus 2013; 24:44-53. [PMID: 23996574 DOI: 10.1002/hipo.22202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 08/21/2013] [Accepted: 08/22/2013] [Indexed: 12/22/2022]
Abstract
Rattin, a specific derivative of humanin in rats, shares the ability with HN to protect neurons against amyloid β (Aβ) peptide-induced cellular toxicity. However, it is still unclear whether Rattin can protect against Aβ-induced deficits in cognition and synaptic plasticity in rats. In the present study, we observed the effects of Rattin and Aβ31-35 on the spatial reference memory and in vivo hippocampal Long-term potentiation of rats by using Morris water maze test and hippocampal field potential recording. Furthermore, the probable molecular mechanism underlying the neuroprotective roles of Rattin was investigated. We showed that intra-hippocampal injection of Rattin effectively prevented the Aβ31-35-induced spatial memory deficits and hippocampal LTP suppression in rats; the Aβ31-35-induced activation of Caspase-3 and inhibition of STAT3 in the hippocampus were also prevented by Rattin treatment. These findings indicate that Rattin treatment can protect spatial memory and synaptic plasticity of rats against Aβ31-35-induced impairments, and the underlying protective mechanism of Rattin may be involved in STAT3 and Caspases-3 pathways. Therefore, application of Rattin or activation of its signaling pathways in the brain might be beneficial to the prevention of Aβ-related cognitive deficits.
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Affiliation(s)
- Zhao-Jun Wang
- Department of Neurobiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, People's Republic of China
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17
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Brureau A, Zussy C, Delair B, Ogier C, Ixart G, Maurice T, Givalois L. Deregulation of hypothalamic-pituitary-adrenal axis functions in an Alzheimer's disease rat model. Neurobiol Aging 2013; 34:1426-39. [DOI: 10.1016/j.neurobiolaging.2012.11.015] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 11/21/2012] [Accepted: 11/22/2012] [Indexed: 10/27/2022]
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18
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Danysz W, Parsons CG. Alzheimer's disease, β-amyloid, glutamate, NMDA receptors and memantine--searching for the connections. Br J Pharmacol 2013; 167:324-52. [PMID: 22646481 DOI: 10.1111/j.1476-5381.2012.02057.x] [Citation(s) in RCA: 335] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
β-amyloid (Aβ) is widely accepted to be one of the major pathomechanisms underlying Alzheimer's disease (AD), although there is presently lively debate regarding the relative roles of particular species/forms of this peptide. Most recent evidence indicates that soluble oligomers rather than plaques are the major cause of synaptic dysfunction and ultimately neurodegeneration. Soluble oligomeric Aβ has been shown to interact with several proteins, for example glutamatergic receptors of the NMDA type and proteins responsible for maintaining glutamate homeostasis such as uptake and release. As NMDA receptors are critically involved in neuronal plasticity including learning and memory, we felt that it would be valuable to provide an up to date review of the evidence connecting Aβ to these receptors and related neuronal plasticity. Strong support for the clinical relevance of such interactions is provided by the NMDA receptor antagonist memantine. This substance is the only NMDA receptor antagonist used clinically in the treatment of AD and therefore offers an excellent tool to facilitate translational extrapolations from in vitro studies through in vivo animal experiments to its ultimate clinical utility.
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Affiliation(s)
- Wojciech Danysz
- Merz Pharmaceuticals GmbH, Eckenheimer Landstraße, Frankfurt am Main, Germany
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19
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Alzheimer's disease related markers, cellular toxicity and behavioral deficits induced six weeks after oligomeric amyloid-β peptide injection in rats. PLoS One 2013; 8:e53117. [PMID: 23301030 PMCID: PMC3534645 DOI: 10.1371/journal.pone.0053117] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 11/28/2012] [Indexed: 11/30/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative pathology associated with aging characterized by the presence of senile plaques and neurofibrillary tangles that finally result in synaptic and neuronal loss. The major component of senile plaques is an amyloid-β protein (Aβ). Recently, we characterized the effects of a single intracerebroventricular (icv) injection of Aβ fragment (25–35) oligomers (oAβ25–35) for up to 3 weeks in rats and established a clear parallel with numerous relevant signs of AD. To clarify the long-term effects of oAβ25–35 and its potential role in the pathogenesis of AD, we determined its physiological, behavioral, biochemical and morphological impacts 6 weeks after injection in rats. oAβ25–35 was still present in the brain after 6 weeks. oAβ25–35 injection did not affect general activity and temperature rhythms after 6 weeks, but decreased body weight, induced short- and long-term memory impairments, increased corticosterone plasma levels, brain oxidative (lipid peroxidation), mitochondrial (caspase-9 levels) and reticulum stress (caspase-12 levels), astroglial and microglial activation. It provoked cholinergic neuron loss and decreased brain-derived neurotrophic factor levels. It induced cell loss in the hippocampic CA subdivisions and decreased hippocampic neurogenesis. Moreover, oAβ25–35 injection resulted in increased APP expression, Aβ1–42 generation, and increased Tau phosphorylation. In conclusion, this in vivo study evidenced that the soluble oligomeric forms of short fragments of Aβ, endogenously identified in AD patient brains, not only provoked long-lasting pathological alterations comparable to the human disease, but may also directly contribute to the progressive increase in amyloid load and Tau pathology, involved in the AD physiopathology.
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20
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The phosphodiesterase-4 inhibitor rolipram reverses Aβ-induced cognitive impairment and neuroinflammatory and apoptotic responses in rats. Int J Neuropsychopharmacol 2012; 15:749-66. [PMID: 21733236 DOI: 10.1017/s1461145711000836] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
β-amyloid (Aβ) peptides play an important role in cognition deficits, neuroinflammation, and apoptosis observed in Alzheimer's disease (AD). Activation of cyclic AMP (cAMP) signalling enhances memory and inhibits inflammatory and apoptotic responses. However, it is not known whether inhibition of phosphodiesterase-4 (PDE4), a critical controller of intracellular cAMP concentrations, affects AD-associated neuroinflammatory and apoptotic responses and whether these responses contribute to deficits of memory mediated by cAMP signalling. We addressed these issues using memory tests and neurochemical measures. Specifically, rats microinfused with aggregated Aβ25-35 (10 μg/side) into bilateral CA1 subregions displayed deficits in learning ability and memory, as evidenced by decreases in escape latency during acquisition trials and exploratory activities in the probe trial in the water-maze task and 24-h retention in the passive avoidance test. These effects were reversed by rolipram (0.1, 0.25 and 0.5 mg/kg.d i.p.), a prototypic PDE4 inhibitor, in a dose-dependent manner. Interestingly, Aβ25-35-treated rats also displayed decreases in expression of phosphorylated cAMP response-element binding protein (pCREB) and Bcl-2, but increases in expression of NF-κB p65 and Bax in the hippocampus; these effects were also reversed by rolipram in a dose-dependent manner. Similar neurochemical results were observed by replacing Aβ25-35 with Aβ1-42, a full-length amyloid peptide that quickly forms toxic oligomers. These results suggest that PDE4 inhibitors such as rolipram may reverse Aβ-induced memory deficits at least in part via the attenuation of neuronal inflammation and apoptosis mediated by cAMP/CREB signalling. PDE4 could be a target for treatment of memory loss associated with AD.
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21
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Solntseva SV, Nikitin VP. Recovery of Memory by the Glutamate NMDA Receptor Agonist D-Cycloserine Depends on the Stage of Development of Amnesia. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s11055-012-9580-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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22
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Griebel G, Pichat P, Pruniaux MP, Beeské S, Lopez-Grancha M, Genet E, Terranova JP, Castro A, Sánchez JA, Black M, Varty GB, Weiner I, Arad M, Barak S, De Levie A, Guillot E. SAR110894, a potent histamine H₃-receptor antagonist, displays procognitive effects in rodents. Pharmacol Biochem Behav 2012; 102:203-14. [PMID: 22542742 DOI: 10.1016/j.pbb.2012.04.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 04/01/2012] [Accepted: 04/10/2012] [Indexed: 12/17/2022]
Abstract
SAR110894 is a novel histamine H₃-R ligand, displaying high and selective affinity for human, rat or mouse H₃-Rs. SAR110894 is a potent H₃-R antagonist at native receptors, reversing R-α-methylhistamine-induced inhibition of electrical field stimulation contraction in the guinea-pig ileum. Additionally, SAR110894 inhibited constitutive GTPγS binding at human H₃-Rs demonstrating inverse agonist properties. In behavioral models addressing certain aspects of cognitive impairment associated with schizophrenia (CIAS) and attention deficit/hyperactivity disorder (ADHD), SAR110894 improved memory performances in several variants of the object recognition task in mice (0.3-3 mg/kg, p.o.) or rats (0.3-1 mg/kg, p.o.). Moreover, SAR110894 (1 mg/kg, p.o.) reversed a deficit in working memory in the Y-maze test, following an acute low dose of phencyclidine (PCP) (0.5 mg/kg, i.p.) in mice sensitized by repeated treatment with a high dose of PCP (10 mg/kg, i.p.). In the latent inhibition (LI) model, SAR110894 potentiated LI in saline-treated rats (1 and 3 mg/kg, i.p.) and reversed abnormally persistent LI induced by neonatal nitric oxide synthase (NOS) inhibition in rodents (0.3-3 mg/kg, i.p.). In a social novelty discrimination task in rats, SAR110894 attenuated selective attention deficit induced by neonatal PCP treatment (3 and 10 mg/kg, p.o.) or a parametric modification of the procedure (3 and 10 mg/kg, p.o.). SAR110894 showed efficacy in several animal models related to the cognitive deficits in Alzheimer's disease (AD). It prevented the occurrence of episodic memory deficit induced by scopolamine in rats (0.01-10 mg/kg, p.o.) or by the central infusion of the toxic amyloid fragment β₂₅₋₃₅ in the object recognition test in mice (1 and 3 mg/kg, p.o.). Altogether, these findings suggest that SAR110894 may be of therapeutic interest for the treatment of the cognitive symptoms of AD, schizophrenia and certain aspects of ADHD.
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Affiliation(s)
- Guy Griebel
- Sanofi, Exploratory Unit, Chilly-Mazarin, France.
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23
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Fedotova J, Soultanov V, Nikitina T, Roschin V, Ordayn N. Ropren(®) is a polyprenol preparation from coniferous plants that ameliorates cognitive deficiency in a rat model of beta-amyloid peptide-(25-35)-induced amnesia. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2012; 19:451-456. [PMID: 22305275 DOI: 10.1016/j.phymed.2011.09.073] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This study assesses the efficacy of a fixed dose of Ropren(®) (a plant preparation isolated from the neutral fraction of an extract of spruce needles) on cognitive impairment in rats with β-amyloid peptide-(25-35)-induced amnesia. Ropren(®) was administered at a dose of 8.6mg/kg for 28 days, per os, to rats with β-amyloid peptide-(25-35)-induced amnesia. Cognitive performance was assessed using the passive avoidance paradigm and the Morris water maze and behavior was assessed using the open field test. After four weeks, Ropren(®) treatment significantly improved non-spatial and spatial learning in rats with β-amyloid peptide-(25-35)-induced amnesia. The results of the present study suggest that Ropren(®), a novel plant preparation, ameliorates cognitive deficiencies in an animal model relevant to Alzheimer's disease.
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Affiliation(s)
- Julia Fedotova
- Laboratory of Neuroendocrinology, I.P. Pavlov Institute of Physiology, Russian Academy of Sciences, Nab. Makarova 6, St. Petersburg 199034, Russia.
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24
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Davis M. NMDA receptors and fear extinction: implications for cognitive behavioral therapy. DIALOGUES IN CLINICAL NEUROSCIENCE 2012. [PMID: 22275851 PMCID: PMC3263393 DOI: 10.31887/dcns.2011.13.4/mdavis] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Based primarily on studies that employ Pavlovian fear conditioning, extinction of conditioned fear has been found to be mediated by N-methyl-D-aspartate (NMDA) receptors in the amygdala and medial prefrontal cortex. This led to the discovery that an NMDA partial agonist, D-cycloserine, could facilitate fear extinction when given systemically or locally into the amygdala. Because many forms of cognitive behavioral therapy depend on fear extinction, this led to the successful use of D-cycloserine as an adjunct to psychotherapy in patients with so-called simple phobias (fear of heights), social phobia, obsessive-compulsive behavior, and panic disorder. Data in support of these conclusions are reviewed, along with some of the possible limitations of D-cycloserine as an adjunct to psychotherapy.
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Affiliation(s)
- Michael Davis
- Emory University, Yerkes National Primate Center and the Center for Behavioral Neuroscience, Atlanta, Georgia, USA.
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25
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Liu P, Jing Y, Collie ND, Campbell SA, Zhang H. Pre-aggregated Aβ25–35 alters arginine metabolism in the rat hippocampus and prefrontal cortex. Neuroscience 2011; 193:269-82. [DOI: 10.1016/j.neuroscience.2011.07.054] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Revised: 07/19/2011] [Accepted: 07/22/2011] [Indexed: 10/17/2022]
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26
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Neuroprotective action of proline-rich polypeptide-1 in β-amyloid induced neurodegeneration in rats. Brain Res Bull 2011; 86:262-71. [PMID: 21839813 DOI: 10.1016/j.brainresbull.2011.08.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 07/22/2011] [Accepted: 08/01/2011] [Indexed: 11/22/2022]
Abstract
It is recognized that the main trigger of Alzheimer disease related neurodegeneration is β-amyloid peptide, which subsequently generates different metabolic disorders in neuron and finally leads to neuronal death. Several biologically active products were tested as neuroprotectors, but only few of them demonstrated any efficiency. Proline-rich polypeptide-1 was tested as a neuroprotective agent on Aβ25-35 animal model of Alzheimer disease. Biochemical analysis (determination of spectrum of neuroactive amino acids, such as glutamate, gamma-aminobutyric acid, glycine, aspartate and taurine), as well as behavioral, electrophysiological and morphological studies were performed to reveal the neuroprotective potential of proline-rich polypeptide in rats. Based on the results of our study it can be concluded that proline-rich polypeptide-1 has a potential to be one of the effective preventive or therapeutic agents against neurodegenerative disorders, such as Alzheimer disease.
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27
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Solntseva SV, Nikitin VP. Effects of agonists of NMDA and serotonin receptors at different stages of amnesia caused by impairment of long-term memory reconsolidation. NEUROCHEM J+ 2010. [DOI: 10.1134/s1819712410030050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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28
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Bergin D, Liu P. Agmatine protects against β-amyloid25-35-induced memory impairments in the rat. Neuroscience 2010; 169:794-811. [DOI: 10.1016/j.neuroscience.2010.05.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 04/13/2010] [Accepted: 05/02/2010] [Indexed: 11/30/2022]
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29
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Duclot F, Meffre J, Jacquet C, Gongora C, Maurice T. Mice knock out for the histone acetyltransferase p300/CREB binding protein-associated factor develop a resistance to amyloid toxicity. Neuroscience 2010; 167:850-63. [PMID: 20219649 DOI: 10.1016/j.neuroscience.2010.02.055] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 02/11/2010] [Accepted: 02/20/2010] [Indexed: 10/19/2022]
Abstract
p300/CREB binding protein-associated factor (PCAF) regulates gene expression by acting through histone acetylation and as a transcription coactivator. Although histone acetyltransferases were involved in the toxicity induced by amyloid-beta (Abeta) peptides, nothing is known about PCAF. We here analyzed the sensitivity of PCAF knockout (KO) mice to the toxic effects induced by i.c.v. injection of Abeta(25-35) peptide, a nontransgenic model of Alzheimer's disease. PCAF wild-type (WT) and KO mice received Abeta(25-35) (1, 3 or 9 nmol) or scrambled Abeta(25-35) (9 nmol) as control. After 7 days, Abeta(25-35) toxicity was measured in the hippocampus of WT mice by a decrease in CA1 pyramidal cells and increases in oxidative stress, endoplasmic reticulum stress and induction of apoptosis. Memory deficits were observed using spontaneous alternation, water-maze learning and passive avoidance. Non-treated PCAF KO mice showed a decrease in CA1 cells and learning alterations. However, Abeta(25-35) injection failed to induce toxicity or worsen the deficits. This resistance to Abeta(25-35) toxicity did not involve changes in glutamate or acetylcholine systems. Examination of enzymes involved in Abeta generation or degradation revealed changes in transcription of presenilins, activity of neprilysin (NEP) and an absence of Abeta(25-35)-induced regulation of NEP activity in PCAF KO mice, partly due to an altered expression of somatostatin (SRIH). We conclude that PCAF regulates the expression of proteins involved in Abeta generation and degradation, thus rendering PCAF KO insensitive to amyloid toxicity. Modulating acetyltransferase activity may offer a new way to develop anti-amyloid therapies.
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Affiliation(s)
- F Duclot
- INSERM U 710, Montpellier, France
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30
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Aguado-Llera D, Arilla-Ferreiro E, Chowen JA, Argente J, Puebla-Jiménez L, Frago LM, Barrios V. 17β-Estradiol protects depletion of rat temporal cortex somatostatinergic system by β-amyloid. Neurobiol Aging 2007; 28:1396-409. [PMID: 16843571 DOI: 10.1016/j.neurobiolaging.2006.06.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Revised: 05/31/2006] [Accepted: 06/12/2006] [Indexed: 01/23/2023]
Abstract
Estradiol prevents amyloid-beta peptide (Abeta)-induced cell death through estrogen receptors (ERs) and modulates somatostatin (SRIF) responsiveness in the rat brain. As intracerebroventricular (ICV) Abeta25-35 administration reduces SRIFergic tone in the temporal cortex of ovariectomized (Ovx) rats, we asked whether 17beta-estradiol (E2) treatment can restore the Abeta25-35 induced changes in SRIF content, SRIF receptor density and adenylyl cyclase (AC) activity, as well as if these effects are mediated by ERs. E2 treatment did not change Abeta25-35 levels in the temporal cortex, but partially restored the SRIFergic parameters affected by Abeta insult and decreased cell death, which was correlated with Akt activation. The ER antagonist ICI 182,780 prevented the protective effect of E2 on sst2 levels, but did not modify SRIF levels. Furthermore, ICI 182,780 treatment further decreased sst2 protein and mRNA levels when administered alone to Abeta25-35-treated rats, suggesting that it may block the effects of endogenous estrogens. These findings indicate that E2 protects the temporal cortical SRIFergic system from Abeta-induced depletion independently of Abeta accumulation.
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Affiliation(s)
- David Aguado-Llera
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Universidad Autónoma de Madrid, Avda. Menéndez Pelayo, Madrid, Spain
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31
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Montiel T, Quiroz-Baez R, Massieu L, Arias C. Role of oxidative stress on beta-amyloid neurotoxicity elicited during impairment of energy metabolism in the hippocampus: protection by antioxidants. Exp Neurol 2006; 200:496-508. [PMID: 16626708 DOI: 10.1016/j.expneurol.2006.02.126] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2005] [Revised: 01/30/2006] [Accepted: 02/07/2006] [Indexed: 11/18/2022]
Abstract
Age-associated oxidative stress has been implicated in neuronal damage linked with Alzheimer's disease (AD). In addition to the role of beta-amyloid peptide (Abeta) in the pathogenesis of AD, reduced glucose oxidative metabolism and decreased mitochondrial activity have been suggested as associated factors. However, the relationship between Abeta toxicity, metabolic impairment, and oxidative stress is far from being understood. In vivo neurotoxicity of Abeta25-35 peptide has been conflicting. However, in previous studies, we have shown that Abeta25-35 consistently induces synaptic toxicity and neuronal death in the hippocampus in vivo, when administered during moderate glycolytic or mitochondrial inhibition. In the present study, we have investigated whether enhancement of Abeta neurotoxicity during these conditions involves oxidative stress. Results show increased lipoperoxidation (LPO) when Abeta is administered in the hippocampus of rats previously treated with the glycolysis inhibitor, iodoacetate. Neuronal damage and LPO are efficiently prevented by vitamin E, while the spin trapper, alpha-phenyl-N-tert-butyl nitrone, shows partial protection. Abeta stimulates LPO in synaptosomes, but toxicity is only observed in the presence of metabolic inhibitors. Damage and LPO are efficiently prevented by vitamin E. The present results suggest an interaction between oxidative stress and metabolic impairment in the Abeta neurotoxic cascade.
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Affiliation(s)
- Teresa Montiel
- Departamento de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México AP 70-253, México DF 04510, México
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32
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Hölscher C. Development of beta-amyloid-induced neurodegeneration in Alzheimer's disease and novel neuroprotective strategies. Rev Neurosci 2006; 16:181-212. [PMID: 16323560 DOI: 10.1515/revneuro.2005.16.3.181] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Alzheimer's disease (AD) is a form of dementia in which people develop rapid neurodegeneration, complete loss of cognitive abilities, and are likely to die prematurely. At present, no treatment for AD is known. One of the hallmarks in the development of AD is the aggregation of amyloid protein fragments in the brain, and much evidence points towards beta-amyloid fragments being one of the main causes of the neurodegenerative processes. This review summarises the present concepts and theories on how AD develops, and lists the evidence that supports them. A cascade of biochemical events is initiated that ultimately leads to neuronal death involving an imbalance of intracellular calcium homeostasis via activation of calcium channels, intracellular calcium stores, and subsequent production of free radicals by calcium-sensitive enzymes. Secondary processes include inflammatory responses that produce more free radicals and the induction of apoptosis. Recently, several new strategies have been proposed to try to ameliorate the neurodegenerative developments associated with AD. These include the activation of neuronal growth factor receptors and insulin-like receptors, both of which have neuroprotective properties. Furthermore, the role of cholesterol and potential protective properties of cholesterol-lowering drugs are under intense investigation. Other promising strategies include the inhibition of beta- and gamma-secretases which produce beta-amyloid, activation of proteases that degrade beta-amyloid, glutamate receptor selective drugs, antioxidants, and metal chelating agents, all of which prevent formation of plaques. Novel drugs that act at different levels of the neurodegenerative processes show great promise to reduce neurodegeneration. They could help to prolong the time of unimpaired cognitive abilities of people who develop AD, allowing them to lead an independent life.
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Affiliation(s)
- Christian Hölscher
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland.
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33
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Hervás-Aguilar A, Puebla-Jiménez L, Burgos-Ramos E, Aguado-Llera D, Arilla-Ferreiro E. Effects of single and continuous administration of amyloid beta-peptide (25-35) on adenylyl cyclase activity and the somatostatinergic system in the rat frontal and parietal cortex. Neuroscience 2005; 135:181-90. [PMID: 16084649 DOI: 10.1016/j.neuroscience.2005.02.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2004] [Revised: 02/07/2005] [Accepted: 02/12/2005] [Indexed: 11/26/2022]
Abstract
It is unknown whether the amyloid beta-peptide (Abeta), a principal component found in extracellular neuritic plaques in the brain of patients with Alzheimer's disease (AD), is capable of altering adenylyl cyclase (AC) activity and the somatostatin (SRIF) receptor-effector system in the cerebral cortex of the patients. Therefore, the objective of this study was to investigate the effect of the beta fragment, beta (25-35), on AC activity and the somatostatinergic system in the rat frontoparietal cortex. A single dose of beta (25-35) (10microg) injected intracerebroventricularly significantly decreased the density of SRIF receptors (27.4%) and increased their affinity (32.2%) in the frontoparietal cortex. The inhibitory effect of SRIF on basal and forskolin (FK)-stimulated AC activity was significantly lower in the beta (25-35)-treated rats when compared with controls. beta (25-35) did not modify Gialpha1, Gialpha2 nor Gialpha3 levels in membranes from the frontoparietal cortex. Continuous infusion of the peptide induced a decrease in the SRIF receptor density in this brain area to a similar extent as that observed 14 days after the single administration of the peptide. Likewise, this treatment decreased the SRIF receptor density in the frontal cortex (15.3%) and parietal cortex (27.2%). This effect was accompanied by a decrease in the SRIF-mediated inhibition of FK-stimulated AC activity (from 41.6% to 25.6%) in the frontal cortex as well by a decrease in basal AC activity (from 36.9% to 31.6%) and FK-stimulated AC activity (from 35.6% to 27.1%) in the parietal cortex. Continuous infusion of Abeta (25-35) had no effect on Gialpha1, Gialpha2 or Gialpha3 levels in membranes from frontal and parietal cortex. However, this treatment caused a decrease in SRIF-like immunoreactivity content in the parietal (38.9%) and frontal (20.4%) cortex. These results suggest that Abeta might be involved in the alterations of somatostatinergic system reported in AD.
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Affiliation(s)
- A Hervás-Aguilar
- Grupo de Neurobioquímica, Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Ctra. Madrid-Barcelona km 33,6, Universidad de Alcalá, E-28871, Alcalá de Henares, Madrid, Spain
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Hughes RN. The value of spontaneous alternation behavior (SAB) as a test of retention in pharmacological investigations of memory. Neurosci Biobehav Rev 2004; 28:497-505. [PMID: 15465137 DOI: 10.1016/j.neubiorev.2004.06.006] [Citation(s) in RCA: 434] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2004] [Revised: 06/10/2004] [Accepted: 06/11/2004] [Indexed: 10/26/2022]
Abstract
Because of its reliance on memory, the tendency for rats, mice and other animals to alternate successive choices of T- or Y-maze arms has assumed considerable popularity in pharmacological studies of spatial memory as a quick and simple measure of retention that avoids the need for extensive training and the use of conventional reinforcers. Two forms of this tendency have been utilized, namely two-trial and continuous spontaneous alternation behavior (SAB). However, as the behavior can also reflect drug-related changes in sensory/attentional, motivational and performance processes, SAB should not be unquestionably accepted as a measure of memory alone. While assessments of post-acquisition drug effects on longer term memory may be possible through the appropriate timing of drug administration, this is more problematic if SAB is used as a measure of shorter term memory. Even though SAB can be a useful index of responsiveness to novelty, its value as a measure of retention is less certain. In this latter respect, a possible alternative to SAB testing might be the recently developed form of the related procedure, responsiveness to change.
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Affiliation(s)
- Robert N Hughes
- Department of Psychology, University of Canterbury, Private Bag 4800, Christchurch, New Zealand.
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35
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Wang SY, Wang HH, Chi CW, Chen CF, Liao JF. Effects of baicalein on β-amyloid peptide-(25–35)-induced amnesia in mice. Eur J Pharmacol 2004; 506:55-61. [PMID: 15588624 DOI: 10.1016/j.ejphar.2004.10.029] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2004] [Revised: 09/21/2004] [Accepted: 10/12/2004] [Indexed: 10/26/2022]
Abstract
Baicalein may act on the benzodiazepine binding sites to exert an anxiolytic-like effect in mice. Since many benzodiazepine drugs have amnesic side-effect and baicalein can protect cultured cortical neurons from beta-amyloid peptide-(25-35)-induced toxicity, this study examined the amnesic effect of baicalein and its effects on beta-amyloid peptide-(25-35) (3 nmol/mouse, i.c.v.)-induced amnesia in mice. Using the step-through passive avoidance test, the results showed that baicalein (10-100 mg/kg, i.p.), unlike the benzodiazepine drug chlordiazepoxide (10 mg/kg, i.p.), had no significant amnesic effect. Baicalein (10-50 mg/kg, i.p.) also had no facilitating effect on the learning and memory. However, one dosage pretreatment, but not post-treatment, of baicalein (5 or 10 mg/kg, i.p.) attenuated beta-amyloid peptide-(25-35)-induced amnesia. Interestingly, post-treatment for 7 or 13 days of baicalein (10-15 mg/kg/day, i.p.), like melatonin (10 mg/kg/day, i.p.), also attenuated beta-amyloid peptide-(25-35)-induced amnesia. Therefore, this study demonstrated that baicalein has protective effect on beta-amyloid peptide-(25-35)-induced amnesia.
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Affiliation(s)
- Sheng-Yun Wang
- Department and Institute of Pharmacology, School of Medicine, National Yang-Ming University, No.155, Sec. 2, Li-Nong Street, Pei-tou Dist. (112), Taipei, Taiwan, Republic of China
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36
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Stepanichev MY, Zdobnova IM, Zarubenko II, Moiseeva YV, Lazareva NA, Onufriev MV, Gulyaeva NV. Amyloid-β(25–35)-induced memory impairments correlate with cell loss in rat hippocampus. Physiol Behav 2004; 80:647-55. [PMID: 14984798 DOI: 10.1016/j.physbeh.2003.11.003] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2003] [Revised: 07/23/2003] [Accepted: 11/13/2003] [Indexed: 10/26/2022]
Abstract
Amyloid beta-peptide (Abeta) plays an important role in the pathophysiology of Alzheimer's disease. The relationship between amnesia induced by central administration of aggregated Abeta(25-35) and neurodegeneration in the hippocampus was investigated. One month after a single intracerebroventricular injection of Abeta(25-35) (15 nmol), male Wistar rats were tested in an eight-arm radial maze. A quantitative evaluation of cell number in hippocampal regions was carried out on H&E-stained brain sections of rats used in the behavioral study. Indices of free radical-mediated processes in the hippocampus were evaluated in additional groups of animals 1, 3, 5, and 30 days after surgery. Abeta(25-35) induced impairments of working and reference memory (RM) as well as neurodegeneration in the CA1 but not in the CA3 field of the hippocampus. A significant correlation between both reference and working memory (WM) impairments and the neuronal cell loss in the hippocampal CA1 region was demonstrated. A gradually developing oxidative stress was evident in the hippocampus of rats treated with Abeta(25-35) as indicated by the increase in 2-thiobarbituric acid (TBARS) reactive substances and superoxide generation. These data suggest the involvement of oxidative stress in Abeta(25-35)-induced neurodegeneration and a relation between memory impairment and neurodegeneration in the CA1 subfield of the hippocampus.
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Affiliation(s)
- Mikhail Yu Stepanichev
- Department of Functional Biochemistry of the Nervous System, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, 5a Butlerov Str., Moscow 117485, Russia
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Raymond CR, Ireland DR, Abraham WC. NMDA receptor regulation by amyloid-beta does not account for its inhibition of LTP in rat hippocampus. Brain Res 2003; 968:263-72. [PMID: 12663096 DOI: 10.1016/s0006-8993(03)02269-8] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Accumulation of amyloid-beta peptide (Abeta) is widely believed to play a critical role in the pathogenesis of Alzheimer's disease. Although amyloid-containing plaques are a key neuropathological feature of AD, soluble forms of Abeta can interfere with synaptic plasticity in the brain, suggesting that this form of the peptide may be responsible for much of the memory deficit seen early in the disease. Here, we investigate the mechanism underlying the effects of Abeta on long-term potentiation (LTP) in area CA1 of rat hippocampus. Extracellular field recordings were made in area CA1 of hippocampal slices taken from young, adult male rats. A non-toxic concentration of Abeta (200 nM) produced a rapid inhibition of LTP induced by 100 Hz stimulation while having no long-term effect on normal synaptic transmission. The same dose of Abeta had no effect on long-term depression (LTD) induced by 1200 pulses at 1 or 3 Hz. Picrotoxin had no effect on the inhibition of LTP, suggesting Abeta does not act by enhancing GABAergic transmission. Since the LTP induction in this study was dependent on N-methyl-D-aspartate (NMDA) receptor activation, we looked at the effect of Abeta on isolated NMDA receptor-mediated field potentials. Abeta produced a small but significant inhibition of NMDA receptor-mediated synaptic potentials ( approximately 25%). However, a low dose of MK-801 (0.5 microM) that produced a similar inhibition of NMDA potentials had no effect on LTP induction but completely blocked LTD induction. These results suggest that Abeta does not inhibit LTP via effects on NMDA receptors, but rather interferes with a downstream pathway.
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Affiliation(s)
- Clarke R Raymond
- Department of Psychology, University of Otago, Box 56, Dunedin, New Zealand.
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Abstract
(1) Dimemorfan, an antitussive for more than 25 years, has previously been reported to be a relative high-affinity ligand at sigma-1 (sigma(1)) receptor with the K(i) value of 151 nM. (2) To test whether dimemorfan has anti-amnesic effects similar to a sigma(1) receptor agonist, this study examined its effects on scopolamine- and beta-amyloid peptide-(25-35)-induced amnesia in mice. (3) Dimemorfan (10-40 mg kg(-1), i.p.) administered 30 min before the training trial, immediately after the training trial, or 30 min before the retention test significantly improved scopolamine (1 mg kg(-1), i.p.)- or beta-amyloid peptide-(25-35) (3 nmol mouse(-1), i.c.v.)-induced amnesia in a step-through passive avoidance test. Dimemorfan (5-40 mg kg(-1), i.p.) pretreatment also attenuated scopolamine (8 mg kg(-1), i.p.)-induced amnesia in a water-maze test. And, these anti-amnesic effects of dimemorfan, like the putative sigma(1) receptor agonist (+)-N-allylnormetazocine ((+)-SKF-10047), were antagonized by a sigma receptor antagonist haloperidol (0.25 mg kg(-1), i.p.). (4) These results indicated that dimemorfan has anti-amnesic effects and acts like a sigma(1) receptor agonist.
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Affiliation(s)
- Hui-Hung Wang
- Department & Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Taipei 112, Taiwan
| | - Jyh-Wei Chien
- Department & Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Taipei 112, Taiwan
| | - Yueh-Ching Chou
- Department of Pharmacy, Veterans General Hospital-Taipei, No. 201, Sec. 2, Shi-Pai Road, Taipei 112, Taiwan
| | - Jyh-Fei Liao
- Department & Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Taipei 112, Taiwan
- Author for correspondence:
| | - Chieh-Fu Chen
- National Research Institute of Chinese Medicine, No. 155-1, Sec. 2, Li-Nong Street, Taipei 112, Taiwan
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Stepanichev MY, Zdobnova IM, Yakovlev AA, Onufriev MV, Lazareva NA, Zarubenko II, Gulyaeva NV. Effects of tumor necrosis factor-alpha central administration on hippocampal damage in rat induced by amyloid beta-peptide (25-35). J Neurosci Res 2003; 71:110-20. [PMID: 12478619 DOI: 10.1002/jnr.10469] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Male Wistar rats received unilateral intrahippocampal injections of 3 nmol (3.18 microg) aggregated Abeta(25-35), intracerebroventricular bilateral injections of 0.5 microg human recombinant TNFalpha or both (Abeta(25-35) + TNFalpha-treated animals). Seven days after the surgery brain sections were stained with cresyl violet (Nissl), for fragmented DNA (TUNEL), glial fibrillar acidic protein (GFAP) and isolectin B4-reactive microglia. In addition, caspase-3 activity in brain regions was measured fluorometrically. The morphology of the hippocampus after the injection of Abeta(25-35) or both Abeta(25-35) and TNFalpha (but not TNFalpha alone) showed cell loss in the CA1 pyramidal cell layer. The extension of neuronal degeneration measured in the CA1 field was significantly larger in Abeta(25-35)-treated groups compared to the contralateral hemisphere of both vehicle-treated controls and animals injected with TNFalpha alone. TNFalpha augmented the Abeta(25-35)-induced damage, significantly increasing the extension of degenerating area. Administration of Abeta(25-35) caused reactive gliosis in the ipsilateral hemisphere as demonstrated by upregulation of GFAP expression and the presence of hypertrophic astrocytes in the hippocampus. This effect was much more prominent in the hippocampi of rats treated with Abeta(25-35) + TNFalpha but absent after administration of TNFalpha alone. In both Abeta(25-35)-treated groups, the damaged area of the hippocampal CA1 field and lateral band of dentate gyrus displayed many darkly stained round isolectin B4-positive phagocyte-like microglial cells. Sparse TUNEL-positive nuclei were found in the hippocampi of rats treated with Abeta(25-35) alone or together with TNFalpha, but not in the control brain sections or in brain sections of TNFalpha-injected animals. The activity of caspase-3 increased significantly in the ipsilateral hippocampus after the injection of Abeta(25-35). Surprisingly, administration of TNFalpha into the cerebral ventricles prevented this Abeta(25-35)-induced increase in hippocampal caspase-3 activity. The results are discussed from the perspective of dual (neuroprotective and neurodestructive) roles of TNF in the brain.
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Affiliation(s)
- Mikhail Yu Stepanichev
- Department of Functional Biochemistry of the Nervous System, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
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Maurice T, Urani A, Phan VL, Romieu P. The interaction between neuroactive steroids and the sigma1 receptor function: behavioral consequences and therapeutic opportunities. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 2001; 37:116-32. [PMID: 11744080 DOI: 10.1016/s0165-0173(01)00112-6] [Citation(s) in RCA: 182] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Steroids, synthesized in peripheral glands or centrally in the brain--the latter being named neurosteroids--exert an important role as modulators of the neuronal activity by interacting with different receptors or ion channels. In addition to the modulation of GABA(A), NMDA or cholinergic receptors, neuroactive steroids interact with an atypical intracellular receptor, the sigma(1) protein. This receptor has been cloned in several species, and highly selective synthetic ligands are available. At the cellular level, sigma1 agonists modulate intracellular calcium mobilization and extracellular calcium influx, NMDA-mediated responses, acetylcholine release, and alter monoaminergic systems. At the behavioral level, the sigma1 receptor is involved in learning and memory processes, the response to stress, depression, neuroprotection and pharmacodependence. Pregnenolone, dehydroepiandrosterone, and their sulfate esters behave as sigma1 agonists, while progesterone is a potent antagonist. This review will detail the physiopathological consequences of these interactions, focusing on recent results on memory and depression. The therapeutical interest of selective sigma1 receptor agonists in alleviating aging-related cognitive deficits will be discussed.
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Affiliation(s)
- T Maurice
- Behavioural Neuropharmacology Group, INSERM U. 336, Institut de Biologie, 4 Bvd Henri IV, 34060, Montpellier, France.
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Wang HH, Chou CJ, Liao JF, Chen CF. Dehydroevodiamine attenuates beta-amyloid peptide-induced amnesia in mice. Eur J Pharmacol 2001; 413:221-5. [PMID: 11226396 DOI: 10.1016/s0014-2999(00)00913-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dehydroevodiamine has been reported to have anticholinesterase activity and an anti-amnesic effect. This study examined the effects of dehydroevodiamine on scopolamine- and beta-amyloid peptide-(25--35)-induced amnesia in mice, using a step-through passive avoidance test. Similarly to the cholinesterase inhibitor, physostigmine (0.03--0.3 mg/kg, i.p.), dehydroevodiamine (0.75--12.0 mg/kg, i.p.) administered 30 min before the training trial, immediately after the training trial, and 30 min before the retention test significantly improved scopolamine- and beta-amyloid peptide-(25--35)-induced amnesia. In beta-amyloid peptide-(25--35)-induced amnesia, the rank order of anti-amnesic potency in these three administration schedules for dehydroevodiamine was different from that for physostigmine. Furthermore, dehydroevodiamine was more potent to improve beta-amyloid peptide-(25--35)-induced amnesia than scopolamine-induced amnesia when administered before the training trial. These results suggested that dehydroevodiamine may have an action other than that of an anticholinesterase and may be a novel and effective ligand for improvement of beta-amyloid type amnesia.
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Affiliation(s)
- H H Wang
- Department and Institute of Pharmacology, National Yang-Ming University, No. 155, Sec. 2, Li-Nong Street, Pei-Tou Dist. (112), Taipei (11221), Taiwan
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42
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Abrahám I, Harkany T, Horvath KM, Veenema AH, Penke B, Nyakas C, Luiten PG. Chronic corticosterone administration dose-dependently modulates Abeta(1-42)- and NMDA-induced neurodegeneration in rat magnocellular nucleus basalis. J Neuroendocrinol 2000; 12:486-94. [PMID: 10844576 DOI: 10.1046/j.1365-2826.2000.00475.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The impact of glucocorticoids on beta-amyloid(1-42) (Abeta(1-42)) and NMDA-induced neurodegeneration was investigated in vivo. Abeta(1-42) or NMDA was injected into the cholinergic magnocellular nucleus basalis in adrenalectomized (ADX) rats, ADX rats supplemented with 25%, 100%, 2x100% corticosterone pellets, or sham-ADX controls. Abeta(1-42)- or NMDA-induced damage of cholinergic nucleus basalis neurones was assessed by quantitative acetylcholinesterase histochemistry. Plasma concentrations of corticosterone and cholinergic fibre loss after Abeta(1-42) or NMDA injection showed a clear U-shaped dose-response relationship. ADX and subsequent loss of serum corticosterone potentiated both the Abeta(1-42) and NMDA-induced neurodegeneration. ADX+25% corticosterone resulted in a 10-90 nM plasma corticosterone concentration, which significantly attenuated the Abeta(1-42) and NMDA neurotoxicity. ADX+100% corticosterone (corticosterone concentrations of 110-270 nM) potently decreased both Abeta(1-42)- and NMDA-induced neurotoxic brain damage. In contrast, high corticosterone concentrations of 310-650 nM potentiated Abeta(1-42)- and NMDA-triggered neurodegeneration. In conclusion, chronic low or high corticosterone concentrations increase the vulnerability of cholinergic cells to neurotoxic insult, while slightly elevated corticosterone levels protect against neurotoxic injury. Enhanced neurotoxicity of NMDA in the presence of high concentrations of specific glucocorticoid receptor agonists suggests that the corticosterone effects are mediated by glucocorticoid receptors.
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Affiliation(s)
- I Abrahám
- Departments of Animal Physiology and Biological Psychiatry, Graduate School of Behavioural and Cognitive Neurosciences, University of Groningen, The Netherlands
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Harkany T, Hortobágyi T, Sasvári M, Kónya C, Penke B, Luiten PG, Nyakas C. Neuroprotective approaches in experimental models of beta-amyloid neurotoxicity: relevance to Alzheimer's disease. Prog Neuropsychopharmacol Biol Psychiatry 1999; 23:963-1008. [PMID: 10621945 DOI: 10.1016/s0278-5846(99)00058-5] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
1. beta-Amyloid peptides (A beta s) accumulate abundantly in the Alzheimer's disease (AD) brain in areas subserving information acquisition and processing, and memory formation. A beta fragments are produced in a process of abnormal proteolytic cleavage of their precursor, the amyloid precursor protein (APP). While conflicting data exist in the literature on the roles of A beta s in the brain, and particularly in AD, recent studies have provided firm experimental evidence for the direct neurotoxic properties of A beta. 2. Sequence analysis of A beta s revealed a high degree of evolutionary conservation and inter-species homology of the A beta amino acid sequence. In contrast, synthetic A beta fragments, even if modified fluorescent or isotope-labeled derivatives, are pharmacological candidates for in vitro and in vivo modeling of their cellular actions. During the past decade, acute injection, prolonged mini-osmotic brain perfusion approaches or A beta infusions into the blood circulation were developed in order to investigate the effects of synthetic A beta s, whereas transgenic models provided insight into the distinct molecular steps of pathological APP cleavage. 3. The hippocampus, caudate putamen, amygdala and neocortex all formed primary targets of acute neurotoxicity screening, but functional consequences of A beta infusions were primarily demonstrated following either intracerebroventricular or basal forebrain (medial septum or magnocellular basal nucleus (MBN)) infusions of A beta fragments. 4. In vivo investigations confirmed that, while the active core of A beta is located within the beta(25-35) sequence, the flanking peptide regions influence not only the folding properties of the A beta fragments, but also their in vivo neurotoxic potentials. 5. It has recently been established that A beta administration deranges neuron-glia signaling, affects the glial glutamate uptake and thereby induces noxious glutamatergic stimulation of nerve cells. In fact, a critical role for N-methyl-D-aspartate (NMDA) receptors was postulated in the neurotoxic processes. Additionally, A beta s might become internalized, either after their selective binding to cell-surface receptors or after membrane association in consequence of their highly lipophilic nature, and induce free radical generation and subsequent oxidative injury. Ca(2+)-mediated neurotoxic events and generation of oxygen free radicals may indeed potentiate each other, or even converge to the same neurotoxic events, leading to cell death. 6. Neuroprotection against A beta toxicity was achieved by both pre- and post-treatment with NMDA receptor channel antagonists. Moreover, direct radical-scavengers, such as vitamin E or vitamin C, attenuated A beta toxicity with high efficacy. Interestingly, combined drug treatments did not necessarily result in additive enhanced neuroprotection. 7. Similarly to the blockade of NMDA receptors, the neurotoxic action of A beta s could be markedly decreased by pharmacological manipulation of voltage-dependent Ca(2+)-channels, serotonergic IA or adenosine A1 receptors, and by drugs eliciting membrane hyperpolarization or indirect blockade of Ca(2+)-mediated intracellular consequences of intracerebral A beta infusions. 8. A beta neurotoxicity might be dose-dependently modulated by trace metals. In spite of the fact that zinc (Zn) may act as a potent inhibitor of the NMDA receptor channel, high Zn doses accelerate A beta fibril formation, stabilize the beta-sheet conformation and thereby potentiate A beta neurotoxicity. Combined trace element supplementation with Se, Mn, or Mg, which prevails over the expression of detoxifying enzymes or counteracts intracellular elevations of Ca2+, may reduce the neurotoxic impact of A beta s. 9. Alterations in the regulatory functions of the hypothalamo-pituitary-adrenal axis may contribute significantly to neurodegenerative changes in the brain. Furthermore, AD patients exhibit substantially increased circadia
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Affiliation(s)
- T Harkany
- Central Research Division of Clinical and Experimental Laboratory Medicine, Haynal Imre University of Health Sciences, Budapest, Hungary.
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Harkany T, Mulder J, Sasvári M, Abrahám I, Kónya C, Zarándi M, Penke B, Luiten PG, Nyakas C. N-Methyl-D-aspartate receptor antagonist MK-801 and radical scavengers protect cholinergic nucleus basalis neurons against beta-amyloid neurotoxicity. Neurobiol Dis 1999; 6:109-21. [PMID: 10343326 DOI: 10.1006/nbdi.1998.0230] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Previous experimental data indicate the involvement of Ca(2+)-related excitotoxic processes, possibly mediated by N-Methyl-D-Aspartate (NMDA) receptors, in beta-amyloid (beta A) neurotoxicity. On the other hand, other lines of evidence support the view that free radical generation is a critical step in the beta A-induced neurodegenerative cascade. In the present study, therefore, a neuroprotective strategy was applied to explore the contributions of each of these pathways in beta A toxicity. beta A(1-42) was injected into the magnocellular nucleus basalis of rats, while neuroprotection was achieved by either single or combined administration of the NMDA receptor antagonist MK-801 (2.5 mg/kg) and/or a vitamin E and C complex (150 mg/kg). The degree of neurodegeneration was determined by testing the animals in consecutive series of behavioral tasks, including elevated plus maze, passive avoidance learning, small open-field and open-field paradigms, followed by acetylcholinesterase (AChE), choline-acetyltransferase (ChAT), and superoxide dismutase (SOD) biochemistry. beta A injected in the nucleus basalis elicited significant anxiety in the elevated plus maze, derangement of passive avoidance learning, and altered spontaneous behaviors in both open-field tasks. A significant decrease in both AChE and ChAT accompanied by a similar decrement of MnSOD, but not of Cu/ZnSOD provided neurochemical substrates for the behavioral changes. Each of the single drug administrations protected against the neurotoxic events, whereas the combined treatment failed to ameliorate beta A toxicity.
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Affiliation(s)
- T Harkany
- Central Research Division, Haynal Imre University of Health Sciences, Budapest, Hungary
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Neuroactive Neurosteroids as Endogenous Effectors for the Sigma1 (σ1) Receptor: Pharmacological Evidence and Therapeutic Opportunities. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0021-5198(19)30781-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Kawabe K, Yoshihara T, Ichitani Y, Iwasaki T. Intrahippocampal D-cycloserine improves MK-801-induced memory deficits: radial-arm maze performance in rats. Brain Res 1998; 814:226-30. [PMID: 9838131 DOI: 10.1016/s0006-8993(98)01043-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In order to investigate whether strychnine-insensitive glycine sites coupled with hippocampal NMDA (N-methyl-d-aspartate) receptors are involved in spatial memory in rats, we examined the effects of intrahippocampal treatment of d-cycloserine (DCS), a glycine-site agonist, on spatial-memory deficits which were produced by an NMDA antagonist MK-801 (dizocilpine) on the radial-arm maze task. After the acquisition of this task, the radial-maze performance was tested under the combined treatments of intraperitoneal MK-801 or saline (SAL) and intrahippocampal DCS or SAL. The results showed that MK-801 impaired the performance, and that DCS improved the MK-801-induced performance impairment. These results suggest that glycine sites are involved in spatial memory through their modulatory action on hippocampal NMDA receptors.
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Affiliation(s)
- K Kawabe
- CREST, Japan Science and Technology Corporation, Japan
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Hölscher C. Possible causes of Alzheimer's disease: amyloid fragments, free radicals, and calcium homeostasis. Neurobiol Dis 1998; 5:129-41. [PMID: 9848086 DOI: 10.1006/nbdi.1998.0193] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Alzheimer's disease (AD) is a form of dementia in which patients develop neurodegeneration and complete loss of cognitive abilities and die prematurely. No treatment is known for this condition. Evidence points toward beta-amyloid as one of the main causes for cytotoxic processes. The cascade of biochemical events that lead to neuronal death appears to be interference with intracellular calcium homeostasis via activation of calcium channels, intracellular calcium stores, and subsequent production of free radicals by calcium-sensitive enzymes. The glutamatergic system seems to be implicated in mediating the toxic processes. Several strategies promise amelioration of neurodegenerative developments as judging from in vitro experiments. Glutamate receptor-selective drugs, antioxidants, inhibitors of nitric oxide synthase, calcium channel antagonists, receptor or enzyme inhibitors, and growth factors promise help. Especially combinations of drugs that act at different levels might prolong patients' health.
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Affiliation(s)
- C Hölscher
- Department of Human Anatomy and Physiology, University College Dublin, Ireland
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O'Mahony S, Harkany T, Rensink AA, Abrahám I, De Jong GI, Varga JL, Zarándi M, Penke B, Nyakas C, Luiten PG, Leonard BE. Beta-amyloid-induced cholinergic denervation correlates with enhanced nitric oxide synthase activity in rat cerebral cortex: reversal by NMDA receptor blockade. Brain Res Bull 1998; 45:405-11. [PMID: 9527015 DOI: 10.1016/s0361-9230(97)00405-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ample experimental evidence indicates that acute beta-amyloid infusion into the nucleus basalis of rats elicits abrupt degeneration of the magnocellular cholinergic neurons projecting to the cerebral cortex. In fact, involvement of a permanent Ca2+ overload, partially via N-methyl-D-aspartate (NMDA) receptors, was proposed as a pivotal mechanism in beta-amyloid-induced neurodegeneration. A definite measure of NMDA receptor-mediated processes and subsequent Ca2+ entry is the induction of Ca2+/calmodulin-activated neuronal nitric oxide synthase (nNOS) in nerve cells. In the present account we therefore assessed activation of nNOS in correlation with cholinergic decline after beta-amyloid(1-42) or beta-amyloid(25-35) infusion into the rat nucleus basalis. The results demonstrate the beta-amyloid conformation-dependent enhancement of cortical nitric oxide synthase (NOS) activity. Furthermore, chronic application of the polyamine site NMDA receptor blocker ifenprodil effectively attenuated beta-amyloid neurotoxicity. We propose that nNOS activation reflects the degree of beta-amyloid-induced excitotoxic injury in a proportional manner. Moreover, Ca2+-mediated processes via NMDA receptors, or direct binding of beta-amyloid to this receptor may be a critical step in the neurotoxic mechanisms in vivo.
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Affiliation(s)
- S O'Mahony
- Department of Pharmacology, University College Galway, Ireland
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Maurice T, Su TP, Privat A. Sigma1 (sigma 1) receptor agonists and neurosteroids attenuate B25-35-amyloid peptide-induced amnesia in mice through a common mechanism. Neuroscience 1998; 83:413-28. [PMID: 9460750 DOI: 10.1016/s0306-4522(97)00405-3] [Citation(s) in RCA: 226] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The sigma1 (sigma 1) receptor agonists exert potent anti-amnesic effects, as they apparently block the learning impairments either induced by the muscarinic receptor antagonist scopolamine, the N-methyl-D-aspartate receptor antagonist dizocilpine or inherently due to the age-related deficits in senescence-accelerated mice. We recently described the amnesia induced by the beta-amyloid-related peptide beta 25-35, administered centrally in an aggregated form, in mice. The deficits were sensitive to cholinomimetics or to N-methyl-D-aspartate/glycine modulatory site agonists. Herein, we examined the effects of sigma 1 receptor ligands on the beta 25-35 peptide-induced amnesia. The effects of neuro(active) steroids, which interact in vitro and in vivo with sigma 1 receptors were examined in parallel. Mnesic capacity was evaluated seven days after administration of aggregated beta 25-35 peptide (3 nmol), using spontaneous alternation in the Y-maze for spatial short-term memory, or after 14 days, using the step-down type passive avoidance test for long-term memory. The sigma 1 receptor agonists (+)-pentazocine, PRE-084, or SA4503 attenuated, in a dose-dependent and bell-shaped manner, the beta 25-35 peptide-induced deficits on both tests. These effects were antagonized by haloperidol or BMY-14802, confirming the sigma 1 receptor pharmacology. Pregnenolone, dehydroepiandrosterone, and their sulphate esters, but not progesterone, also dose-dependently attenuated the beta 25-35 peptide-induced deficits. Progesterone blocked the beneficial effects of each other neurosteroid, behaving as an antagonist. Furthermore, haloperidol blocked the effects induced by neurosteroids, whereas progesterone antagonized the effects of the non-steroidal sigma 1 receptor agonists, showing a clear crossed pharmacology of different drug classes. These results demonstrate that: (i) the anti-amnesic effect of sigma 1 receptor agonists may be of therapeutic relevance in pathological states affecting the cholinergic and/or glutamatergic systems, such as in pathological aging; (ii) neurosteroids play an important role in learning processes and may collectively constitute a therapeutic target; (iii) the interaction between sigma 1 systems and neurosteroids appears indeed of behavioural relevance.
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Affiliation(s)
- T Maurice
- I.N.S.E.R.M. Unité 336, Développement, Plasticité et Vieillissement du Système Nerveux, Montpellier, France
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