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Poceviciute I, Brazaityte A, Buisas R, Vengeliene V. Scopolamine animal model of memory impairment. Behav Brain Res 2025; 479:115344. [PMID: 39566583 DOI: 10.1016/j.bbr.2024.115344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2024] [Revised: 11/15/2024] [Accepted: 11/18/2024] [Indexed: 11/22/2024]
Abstract
In this study, we reassessed the suitability of a commonly used pharmacological animal model of Alzheimer's disease (AD) - scopolamine-induced memory impairment. The goal of the study was to explore if this animal model induces other behavioral changes associated with AD. One of the key behavioral features of AD, manifesting already during the early stages of the illness, is apathy-like behavior. We also evaluated how behavioral alterations induced by scopolamine compare to those seen in healthy aging animals. To achieve these goals, locomotor activity and short-term memory of young male Wistar rats were tested in the open field, novel object recognition (NOR) and T-maze spontaneous alternation tests before, during and after 21 daily administrations of scopolamine. Three-, ten- and nineteen-month-old male and female rats were used to measure age-related changes in these behaviors. Our data showed that although both scopolamine treatment and aging reduced the number of approaches to the objects and their exploration time during the NOR test, correlation with impaired object recognition memory was only observed in the scopolamine treated animals. Furthermore, treatment with scopolamine significantly increased the locomotor activity, which could be observed even one week after treatment discontinuation. Contrary, locomotor activity in older rats was significantly lower than that of younger rats. These findings demonstrate that the animal model of scopolamine-induced memory impairment fails to incorporate apathy-like symptoms characteristic to the AD and age-related reduction in physical activity of older rats.
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Affiliation(s)
- Ieva Poceviciute
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Lithuania
| | - Agne Brazaityte
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Lithuania
| | - Rokas Buisas
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Lithuania
| | - Valentina Vengeliene
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Lithuania.
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2
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Chen Y, Branch A, Shuai C, Gallagher M, Knierim JJ. Object-place-context learning impairment correlates with spatial learning impairment in aged Long-Evans rats. Hippocampus 2024; 34:88-99. [PMID: 38073523 PMCID: PMC10843702 DOI: 10.1002/hipo.23591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 09/28/2023] [Accepted: 11/18/2023] [Indexed: 01/23/2024]
Abstract
The hippocampal formation is vulnerable to the process of normal aging. In humans, the extent of this age-related deterioration varies among individuals. Long-Evans rats replicate these individual differences as they age, and therefore they serve as a valuable model system to study aging in the absence of neurodegenerative diseases. In the Morris water maze, aged memory-unimpaired (AU) rats navigate to remembered goal locations as effectively as young rats and demonstrate minimal alterations in physiological markers of synaptic plasticity, whereas aged memory-impaired (AI) rats show impairments in both spatial navigation skills and cellular and molecular markers of plasticity. The present study investigates whether another cognitive domain is affected similarly to navigation in aged Long-Evans rats. We tested the ability of young, AU, and AI animals to recognize novel object-place-context (OPC) configurations and found that performance on the novel OPC recognition paradigm was significantly correlated with performance on the Morris water maze. In the first OPC test, young and AU rats, but not AI rats, successfully recognized and preferentially explored objects in novel OPC configurations. In a second test with new OPC configurations, all age groups showed similar OPC associative recognition memory. The results demonstrated similarities in the behavioral expression of associative, episodic-like memory between young and AU rats and revealed age-related, individual differences in functional decline in both navigation and episodic-like memory abilities.
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Affiliation(s)
- Yuxi Chen
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland, USA
| | - Audrey Branch
- Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Cecelia Shuai
- Undergraduate Studies, Krieger School of Arts and Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Michela Gallagher
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland, USA
- Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, Maryland, USA
| | - James J Knierim
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland, USA
- Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, Maryland, USA
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3
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Branch AE, Glover LR, Gallagher M. Individual differences in age-related neurocognitive outcomes: within-subject assessment of memory for odors. Front Aging Neurosci 2023; 15:1238444. [PMID: 37842120 PMCID: PMC10569039 DOI: 10.3389/fnagi.2023.1238444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Accepted: 09/13/2023] [Indexed: 10/17/2023] Open
Abstract
Cognitive decline is a common feature of aging, particularly in memory domains supported by the medial temporal lobe (MTL). The ability to identify intervention strategies to treat or prevent this decline is challenging due to substantial variability between adults in terms of age of onset, rate and severity of decline, and many factors that could influence cognitive reserve. These factors can be somewhat mitigated by use of within-subject designs. Aged outbred Long-Evans rats have proven useful for identifying translationally relevant substrates contributing to age-related decline in MTL-dependent memory. In this population, some animals show reliable impairment on MTL-dependent tasks while others perform within the range of young adult rats. However, currently there are relatively few within-subject behavior protocols for assessing MTL function over time, and most require extensive training and appetitive motivation for associative learning. In the current study, we aimed to test whether water maze learning impairments in aged Long-Evans rats would be predictive of delayed recognition memory impairments and whether these odor memory impairments would be stable within subjects over multiple rounds of testing.
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Affiliation(s)
- Audrey E. Branch
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, United States
| | - Lucas R. Glover
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, United States
| | - Michela Gallagher
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, United States
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, United States
- Johns Hopkins Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD, United States
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4
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Portero-Tresserra M, Galofré-López N, Pallares E, Gimenez-Montes C, Barcia C, Granero R, Rojic-Becker D, Vale-Martínez A, Martí-Nicolovius M, Guillazo-Blanch G. Effects of Caloric Restriction on Spatial Object Recognition Memory, Hippocampal Neuron Loss and Neuroinflammation in Aged Rats. Nutrients 2023; 15:nu15071572. [PMID: 37049417 PMCID: PMC10096994 DOI: 10.3390/nu15071572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 04/14/2023] Open
Abstract
Age-related neurobiological changes significantly affect hippocampal structure and function, such that the main cognitive impairments associated with aging are related to the integrity of this brain structure, including the deterioration in spatial object recognition (SOR) memory. Previous studies have shown that intrinsic factors such as neuroinflammation, as well as lifestyle factors such as diet, can affect aging-associated brain functions and cognitive performance. In this regard, caloric restriction (CR) produces beneficial effects on health and life expectancy, although its ability to slow down age-dependent effects on cognitive decline and hippocampus (HPC) functioning remains unclear. Therefore, we set out to evaluate the effects of CR on SOR memory in aged male Wistar rats, as well as those on hippocampal neuron loss, neurogenesis and inflammation. The data show that CR in aged rats attenuates the decline in SOR memory, age-associated hippocampal neuron loss, and age-dependent microglial activation. Furthermore, we found a significant reduction in neurogenesis in the dentate gyrus of the old animals relative to adult rats. These findings support the positive effect of CR on SOR memory, suggesting that it dampens hippocampal neuronal loss and reduces proinflammatory activity.
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Affiliation(s)
- Marta Portero-Tresserra
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Neus Galofré-López
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Elisabet Pallares
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Claudia Gimenez-Montes
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Carlos Barcia
- Departament de Bioquímica i Biologia Molecular, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Roser Granero
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
- Ciber Fisiopatología Obesidad y Nutrición (CIBERObn), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Psychoneurobiology of Eating and Addictive Behaviors Group, Neurosciences Programme, Bellvitge Institute for Biomedical Research (IDIBELL), 08908 Barcelona, Spain
| | - Divka Rojic-Becker
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Anna Vale-Martínez
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Margarita Martí-Nicolovius
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Gemma Guillazo-Blanch
- Departament de Psicobiologia i Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
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Ferreira AC, Sousa N, Sousa JC, Marques F. Age-related changes in mice behavior and the contribution of lipocalin-2. Front Aging Neurosci 2023; 15:1179302. [PMID: 37168715 PMCID: PMC10164932 DOI: 10.3389/fnagi.2023.1179302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 03/28/2023] [Indexed: 05/13/2023] Open
Abstract
Aging causes considerable changes in the nervous system, inducing progressive and long-lasting loss of physiological integrity and synaptic plasticity, leading to impaired brain functioning. These age-related changes quite often culminate in behavioral dysfunctions, such as impaired cognition, which can ultimately result in various forms of neurodegenerative disorders. Still, little is known regarding the effects of aging on behavior. Moreover, the identification of factors involved in regenerative plasticity, in both the young and aged brain, is scarce but crucial from a regenerative point of view and for our understanding on the mechanisms that control the process of normal aging. Recently, we have identified the iron-trafficking protein lipocalin-2 (LCN2) as novel regulator of animal behavior and neuronal plasticity in the young adult brain. On the other hand, others have proposed LCN2 as a biological marker for disease progression in neurodegenerative disorders such as Alzheimer's disease and multiple sclerosis. Still, and even though LCN2 is well accepted as a regulator of neural processes in the healthy and diseased brain, its contribution in the process of normal aging is not known. Here, we performed a broad analysis on the effects of aging in mice behavior, from young adulthood to middle and late ages (2-, 12-, and 18-months of age), and in the absence of LCN2. Significant behavioral differences between aging groups were observed in all the dimensions analyzed and, in mice deficient in LCN2, aging mainly reduced anxiety, while sustained depressive-like behavior observed at younger ages. These behavioral changes imposed by age were further accompanied by a significant decrease in cell survival and neuronal differentiation at the hippocampus. Our results provide insights into the role of LCN2 in the neurobiological processes underlying brain function and behavior attributed to age-related changes.
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Affiliation(s)
- Ana Catarina Ferreira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, Braga, Portugal
- ICVS/3B’s—PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, Braga, Portugal
- ICVS/3B’s—PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - João Carlos Sousa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, Braga, Portugal
- ICVS/3B’s—PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Fernanda Marques
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, Braga, Portugal
- ICVS/3B’s—PT Government Associate Laboratory, Braga/Guimarães, Portugal
- *Correspondence: Fernanda Marques,
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Wheelan N, Seckl JR, Yau JLW. 11β-Hydroxysteroid dehydrogenase 1 deficiency prevents PTSD-like memory in young adult mice. Psychoneuroendocrinology 2022; 146:105945. [PMID: 36183622 DOI: 10.1016/j.psyneuen.2022.105945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 08/21/2022] [Accepted: 09/24/2022] [Indexed: 10/14/2022]
Abstract
Post-traumatic stress disorder (PTSD) is characterized by the co-existence of a persistent strong memory of the traumatic experience and amnesia for the peritraumatic context. Most animal models, however, fail to account for the contextual amnesia which is considered to play a critical role in the etiology of PTSD intrusive memories. It is also unclear how aging affects PTSD-like memory. Glucocorticoids alter the formation and retention of fear-associated memory. Here, we investigated whether a deficiency of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) (an intracellular glucocorticoid generating enzyme) and aging modulates fear conditioning and PTSD-like memory in mice. We first measured memory in 6 months and 24 months old 11β-HSD1 deficient (HSD1 KO) and wildtype (WT) mice following paired tone-shock fear conditioning. Then, separate groups of mice were exposed to restraint stress immediately after unpaired tone-shock contextual fear conditioning. Compared with young controls, aged WT mice exhibited enhanced auditory cued fear memory, but contextual fear memory was not different. Contextual fear memory retention was attenuated in both young and aged HSD1 KO mice. In contrast, auditory cued fear memory was reduced 24 h after training only in aged HSD1 KO mice. When fear conditioned with stress, WT mice displayed PTSD-like memory (i.e., increased fear to tone not predictive of shock and reduced fear to 'aversive' conditioning context); this was unchanged with aging. In contrast, young HSD1 KO mice fear conditioned with stress showed normal fear memory (i.e., increased fear response to conditioning context), as observed in WT mice fear conditioned alone. While aged HSD1 KO mice fear conditioned with stress also displayed normal contextual fear memory, the fear response to the 'safe' tone remained. Thus, a deficiency of 11β-HSD1 protects against both amnesia for the conditioning context and hypermnesia for a salient tone in young adult mice but only contextual amnesia is prevented in aged mice. These results suggest that brain 11β-HSD1 generated glucocorticoids make a significant contribution to fear conditioning and PTSD-like memory. 11β-HSD1 inhibition may be useful in prevention and/or treatment of PTSD.
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Affiliation(s)
- Nicola Wheelan
- Centre for Cardiovascular Science, University of Edinburgh, United Kingdom
| | - Jonathan R Seckl
- Centre for Cardiovascular Science, University of Edinburgh, United Kingdom
| | - Joyce L W Yau
- Centre for Cardiovascular Science, University of Edinburgh, United Kingdom; Centre for Clinical Brain Sciences, University of Edinburgh, United Kingdom.
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7
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Ganoderma tsugae prevents cognitive impairment and attenuates oxidative damage in d-galactose-induced aging in the rat brain. PLoS One 2022; 17:e0266331. [PMID: 35390035 PMCID: PMC8989198 DOI: 10.1371/journal.pone.0266331] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 03/02/2022] [Indexed: 11/19/2022] Open
Abstract
Lingzhi has long been regarded as having life-prolonging effects. Research in recent years has also reported that Lingzhi possesses anti-tumor, anti-inflammatory, immunomodulatory, hepatoprotective, and anti-lipogenic effects. The D-galactose (D-gal, 100 mg/kg/day)-induced aging Long-Evans rats were simultaneously orally administered a DMSO extract of Ganoderma tsugae (GTDE, 200 μg/kg/day) for 25 weeks to investigate the effects of GTDE on oxidative stress and memory deficits in the D-galactose-induced aging rats. We found that GTDE significantly improved the locomotion and spatial memory and learning in the aging rats. GTDE alleviated the aging-induced reduction of dendritic branching in neurons of the hippocampus and cerebral cortex. Immunoblotting revealed a significant increase in the protein expression levels of the superoxide dismutase-1 (SOD-1) and catalase, and the brain-derived neurotrophic factor (BDNF) in rats that received GTDE. D-gal-induced increase in the lipid peroxidation product 4-hydroxynonenal (4-HNE) was significantly attenuated after the administration of GTDE, and pyrin domain-containing 3 protein (NLRP3) revealed a significant decrease in NLRP3 expression after GTDE administration. Lastly, GTDE significantly reduced the advanced glycosylation end products (AGEs). In conclusion, GTDE increases antioxidant capacity and BDNF expression of the brain, protects the dendritic structure of neurons, and reduces aging-induced neuronal damage, thereby attenuating cognitive impairment caused by aging.
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McQuail JA, Dunn AR, Stern Y, Barnes CA, Kempermann G, Rapp PR, Kaczorowski CC, Foster TC. Cognitive Reserve in Model Systems for Mechanistic Discovery: The Importance of Longitudinal Studies. Front Aging Neurosci 2021; 12:607685. [PMID: 33551788 PMCID: PMC7859530 DOI: 10.3389/fnagi.2020.607685] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/30/2020] [Indexed: 12/14/2022] Open
Abstract
The goal of this review article is to provide a resource for longitudinal studies, using animal models, directed at understanding and modifying the relationship between cognition and brain structure and function throughout life. We propose that forthcoming longitudinal studies will build upon a wealth of knowledge gleaned from prior cross-sectional designs to identify early predictors of variability in cognitive function during aging, and characterize fundamental neurobiological mechanisms that underlie the vulnerability to, and the trajectory of, cognitive decline. Finally, we present examples of biological measures that may differentiate mechanisms of the cognitive reserve at the molecular, cellular, and network level.
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Affiliation(s)
- Joseph A. McQuail
- Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine, Columbia, SC, United States
| | - Amy R. Dunn
- The Jackson Laboratory, Bar Harbor, ME, United States
| | - Yaakov Stern
- Cognitive Neuroscience Division, Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Carol A. Barnes
- Departments of Psychology and Neuroscience, University of Arizona, Tucson, AZ, United States
- Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ, United States
| | - Gerd Kempermann
- CRTD—Center for Regenerative Therapies Dresden, Technische Universität Dresden, Dresden, Germany
- German Center for Neurodegenerative Diseases (DZNE), Helmholtz Association of German Research Centers (HZ), Dresden, Germany
| | - Peter R. Rapp
- Laboratory of Behavioral Neuroscience, Neurocognitive Aging Section, National Institute on Aging, Baltimore, MD, United States
| | | | - Thomas C. Foster
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
- Genetics and Genomics Program, University of Florida, Gainesville, FL, United States
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Balietti M, Pugliese A, Conti F. In aged rats, differences in spatial learning and memory influence the response to late-life Environmental Enrichment. Exp Gerontol 2020; 146:111225. [PMID: 33388381 DOI: 10.1016/j.exger.2020.111225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/05/2020] [Accepted: 12/23/2020] [Indexed: 11/26/2022]
Abstract
It has clearly been demonstrated that cognitive stimulation, physical exercise, and social engagement help counteract age-related cognitive decline. However, several important issues remain to be addressed. Given the wide differences in cognitive impairment found among individuals of the same age, identifying the subjects who will benefit most from late-life interventions is one such issue. Environmental Enrichment (EE) is a particularly valuable approach to do this. In this study, aged (21-month-old) rats were assigned to a better (BL) or a worse (WL) learner group (training phase) and to a non-impaired (NI) or an impaired (I) group (probe phase) by their performance on the Morris Water Maze, using the test performances of adult (12-month-old) rats as the cut-offs. The aged rats were retested after a 12-week EE or standard housing (SH) protocol. After 12 weeks, the performances of SH rats had deteriorated, whereas all rats benefited from EE, albeit in different ways. In particular, the animals assigned to the BL and the NI groups prior to EE still performed as well as the adult rats (performance preservation) whereas, critically, the animals assigned to the WL and the I groups before EE showed such improved performances that they reached the level of the adult rats (performance improvement), despite having aged further. EE seems to induce the preservation in BLs and the improvement in WLs of spatial search strategies and the preservation in NIs and the increase in Is of a focused and protract research of the escape point. Our findings suggest that late-life EE prevents spatial learning and memory decline in still cognitively preserved animals and stimulates residual functional reserve in already cognitively compromised animals. Future research should focus on individually tailored stimulation protocols to improve their effect and afford a better understanding of the underlying processes.
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Affiliation(s)
- Marta Balietti
- Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy.
| | - Arianna Pugliese
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy.
| | - Fiorenzo Conti
- Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy; Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy.
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De Risi M, Torromino G, Tufano M, Moriceau S, Pignataro A, Rivagorda M, Carrano N, Middei S, Settembre C, Ammassari‐Teule M, Gardoni F, Mele A, Oury F, De Leonibus E. Mechanisms by which autophagy regulates memory capacity in ageing. Aging Cell 2020; 19:e13189. [PMID: 32729663 PMCID: PMC7511873 DOI: 10.1111/acel.13189] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 06/08/2020] [Accepted: 06/13/2020] [Indexed: 12/25/2022] Open
Abstract
Autophagy agonists have been proposed to slow down neurodegeneration. Spermidine, a polyamine that acts as an autophagy agonist, is currently under clinical trial for the treatment of age‐related memory decline. How Spermidine and other autophagy agonists regulate memory and synaptic plasticity is under investigation. We set up a novel mouse model of mild cognitive impairment (MCI), in which middle‐aged (12‐month‐old) mice exhibit impaired memory capacity, lysosomes engulfed with amyloid fibrils (β‐amyloid and α‐synuclein) and impaired task‐induced GluA1 hippocampal post‐translation modifications. Subchronic treatment with Spermidine as well as the autophagy agonist TAT‐Beclin 1 rescued memory capacity and GluA1 post‐translational modifications by favouring the autophagy/lysosomal‐mediated degradation of amyloid fibrils. These findings provide new mechanistic evidence on the therapeutic relevance of autophagy enhancers which, by improving the degradation of misfolded proteins, slow down age‐related memory decline.
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Affiliation(s)
- Maria De Risi
- Telethon Institute of Genetics and Medicine Telethon Foundation Pozzuoli Italy
- Institute of Biochemistry and Cell Biology (IBBC) National Research Council Rome Italy
| | - Giulia Torromino
- Telethon Institute of Genetics and Medicine Telethon Foundation Pozzuoli Italy
- Institute of Biochemistry and Cell Biology (IBBC) National Research Council Rome Italy
| | - Michele Tufano
- Telethon Institute of Genetics and Medicine Telethon Foundation Pozzuoli Italy
| | - Stéphanie Moriceau
- Institut National de la Santé et de la Recherche Médicale (INSERM) U1151 Institut Necker Enfants‐Malades (INEM) Université Paris Descartes‐Sorbonne–Paris Cité Paris France
| | - Annabella Pignataro
- Laboratory of Psychobiology Department of Experimental Neurology Santa Lucia Foundation Rome Italy
- Institute of Translational Pharmacology (IFT) National Research Council Rome Italy
| | - Manon Rivagorda
- Institut National de la Santé et de la Recherche Médicale (INSERM) U1151 Institut Necker Enfants‐Malades (INEM) Université Paris Descartes‐Sorbonne–Paris Cité Paris France
| | - Nicolò Carrano
- Department of Pharmacological and Biomolecular Sciences University of Milan Milan Italy
| | - Silvia Middei
- Institute of Biochemistry and Cell Biology (IBBC) National Research Council Rome Italy
| | - Carmine Settembre
- Telethon Institute of Genetics and Medicine Telethon Foundation Pozzuoli Italy
| | - Martine Ammassari‐Teule
- Institute of Biochemistry and Cell Biology (IBBC) National Research Council Rome Italy
- Laboratory of Psychobiology Department of Experimental Neurology Santa Lucia Foundation Rome Italy
| | - Fabrizio Gardoni
- Department of Pharmacological and Biomolecular Sciences University of Milan Milan Italy
| | - Andrea Mele
- Department of Biology and Biotechnology "C. Darwin" Sapienza University of Rome Rome Italy
- Center for Research in Neurobiology "D. Bovet" Sapienza University of Rome Rome Italy
| | - Franck Oury
- Institut National de la Santé et de la Recherche Médicale (INSERM) U1151 Institut Necker Enfants‐Malades (INEM) Université Paris Descartes‐Sorbonne–Paris Cité Paris France
| | - Elvira De Leonibus
- Telethon Institute of Genetics and Medicine Telethon Foundation Pozzuoli Italy
- Institute of Biochemistry and Cell Biology (IBBC) National Research Council Rome Italy
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11
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Febo M, Rani A, Yegla B, Barter J, Kumar A, Wolff CA, Esser K, Foster TC. Longitudinal Characterization and Biomarkers of Age and Sex Differences in the Decline of Spatial Memory. Front Aging Neurosci 2020; 12:34. [PMID: 32153384 PMCID: PMC7044155 DOI: 10.3389/fnagi.2020.00034] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 02/04/2020] [Indexed: 01/10/2023] Open
Abstract
The current longitudinal study examined factors (sex, physical function, response to novelty, ability to adapt to a shift in light/dark cycle, brain connectivity), which might predict the emergence of impaired memory during aging. Male and female Fisher 344 rats were tested at 6, 12, and 18 months of age. Impaired spatial memory developed in middle-age (12 months), particularly in males, and the propensity for impairment increased with advanced age. A reduced response to novelty was observed over the course of aging, which is inconsistent with cross-sectional studies. This divergence likely resulted from differences in the history of environmental enrichment/impoverishment for cross-sectional and longitudinal studies. Animals that exhibited lower level exploration of the inner region on the open field test exhibited better memory at 12 months. Furthermore, males that exhibited a longer latency to enter a novel environment at 6 months, exhibited better memory at 12 months. For females, memory at 12 months was correlated with the ability to behaviorally adapt to a shift in light/dark cycle. Functional magnetic resonance imaging of the brain, conducted at 12 months, indicated that the decline in memory was associated with altered functional connectivity within different memory systems, most notably between the hippocampus and multiple regions such as the retrosplenial cortex, thalamus, striatum, and amygdala. Overall, some factors, specifically response to novelty at an early age and the capacity to adapt to shifts in light cycle, predicted spatial memory in middle-age, and spatial memory is associated with corresponding changes in brain connectivity. We discuss similarities and differences related to previous longitudinal and cross-sectional studies, as well as the role of sex differences in providing a theoretical framework to guide future longitudinal research on the trajectory of cognitive decline. In addition to demonstrating the power of longitudinal studies, these data highlight the importance of middle-age for identifying potential predictive indicators of sexual dimorphism in the trajectory in brain and cognitive aging.
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Affiliation(s)
- Marcelo Febo
- Department of Psychiatry, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Asha Rani
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Brittney Yegla
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Jolie Barter
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Ashok Kumar
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States
| | - Christopher A Wolff
- Department of Physiology and Functional Genomics, Myology Institute, University of Florida, Gainesville, FL, United States
| | - Karyn Esser
- Department of Physiology and Functional Genomics, Myology Institute, University of Florida, Gainesville, FL, United States
| | - Thomas C Foster
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States.,Genetics and Genomics Program, University of Florida, Gainesville, FL, United States
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Pavón-Fuentes N, Marín-Prida J, Llópiz-Arzuaga A, Falcón-Cama V, Campos-Mojena R, Cervantes-Llanos M, Piniella-Matamoros B, Pentón-Arias E, Pentón-Rol G. Phycocyanobilin reduces brain injury after endothelin-1- induced focal cerebral ischaemia. Clin Exp Pharmacol Physiol 2019; 47:383-392. [PMID: 31732975 DOI: 10.1111/1440-1681.13214] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 09/27/2019] [Accepted: 11/12/2019] [Indexed: 12/11/2022]
Abstract
Pharmacological therapies for interrupting biochemical events of the ischaemic cascade and protecting against stroke in humans are as yet unavailable. Up to now, the neuroprotective activity in cerebral ischaemia of phycocyanobilin (PCB), a tetrapyrrolic natural antioxidant, has not been fully examined. Here, we evaluated if PCB protects PC12 neuronal cells against oxygen and glucose deprivation plus reperfusion, and its protective effects in a rat model of endothelin-1-induced focal brain ischaemia. PCB was purified from the cyanobacteria Spirulina platensis and characterized by spectrophotometric, liquid and gas chromatography and mass spectrometry techniques. In Wistar rats, PCB at 50, 100 and 200 μg/kg or phosphate-buffered saline (vehicle) was administered intraperitoneally at equal subdoses in a therapeutic schedule (30 minutes, 1, 3 and 6 hours after the surgery). Brain expression of myelin basic protein (MBP) and the enzyme CNPase was determined by immunoelectron microscopy. PCB was obtained with high purity (>95%) and the absence of solvent contaminants and was able to ameliorate PC12 cell ischaemic injury. PCB treatment significantly decreased brain infarct volume, limited the exploratory behaviour impairment and preserved viable cortical neurons in ischaemic rats in a dose-dependent manner, compared to the vehicle group. Furthermore, PCB at high doses restored the MBP and CNPase expression levels in ischaemic rats. An improved PCB purification method from its natural source is reported, obtaining PCB that is suitable for pharmacological trials showing neuroprotective effects against experimental ischaemic stroke. Therefore, PCB could be a therapeutic pharmacological alternative for ischaemic stroke patients.
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Affiliation(s)
| | - Javier Marín-Prida
- Centre for Research and Biological Evaluations (CEIEB), Institute of Pharmacy and Food, University of Havana, Havana, Cuba
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13
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González-Fraguela ME, Blanco-Lezcano L, Fernandez-Verdecia CI, Serrano Sanchez T, Robinson Agramonte MDLA, Cardellá Rosales LL. Cellular Redox Imbalance and Neurochemical Effect in Cognitive-Deficient Old Rats. Behav Sci (Basel) 2018; 8:bs8100093. [PMID: 30322129 PMCID: PMC6211049 DOI: 10.3390/bs8100093] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 09/25/2018] [Accepted: 10/08/2018] [Indexed: 01/24/2023] Open
Abstract
The purpose of the present study is to access the linkage between dysregulation of glutamatergic neurotransmission, oxidative metabolism, and serine signaling in age-related cognitive decline. In this work, we evaluated the effect of natural aging in rats on the cognitive abilities for hippocampal-dependent tasks. Oxidative metabolism indicators are glutathione (GSH), malondialdehyde (MDA) concentrations, and cytosolic phospholipase A2 (PLA2) activity. In addition, neurotransmitter amino acid (L-Glutamic acid, γ-aminobutyric acid (GABA), DL-Serine and DL-Aspartic acid) concentrations were studied in brain areas such as the frontal cortex (FC) and hippocampus (HPC). The spatial long-term memory revealed significant differences among experimental groups: the aged rats showed an increase in escape latency to the platform associated with a reduction of crossings and spent less time on the target quadrant than young rats. Glutathione levels decreased for analyzed brain areas linked with a significant increase in MDA concentrations and PLA2 activity in cognitive-deficient old rats. We found glutamate levels only increased in the HPC, whereas a reduced level of serine was found in both regions of interest in cognitive-deficient old rats. We demonstrated that age-related changes in redox metabolism contributed with alterations in synaptic signaling and cognitive impairment.
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Affiliation(s)
- Maria Elena González-Fraguela
- Immunochemical Department, International Center for Neurological Restoration, 25th Ave, Playa, 15805, PC 11300 Havana, Cuba.
| | - Lisette Blanco-Lezcano
- Experimental Neurophysiology Department, International Center of Neurological Restoration (CIREN) Ave. 25 No. 15805 e/158 and 160, Playa, Havana 11300, Cuba.
| | - Caridad Ivette Fernandez-Verdecia
- Experimental Neurophysiology Department, International Center of Neurological Restoration (CIREN) Ave. 25 No. 15805 e/158 and 160, Playa, Havana 11300, Cuba.
| | - Teresa Serrano Sanchez
- Immunochemical Department, International Center for Neurological Restoration, 25th Ave, Playa, 15805, PC 11300 Havana, Cuba.
| | | | - Lidia Leonor Cardellá Rosales
- Physiologic Sciences Department, Latin American Medicine School, Carretera Panamericana, Kilómetro 3 1/2 Municipio Playa, Habana 19148, Cuba.
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Marrone DF, Satvat E, Patel A. Age-related Deficits in Recognition Memory are Protocol-Dependent. Aging Dis 2018; 9:798-807. [PMID: 30271657 PMCID: PMC6147594 DOI: 10.14336/ad.2017.1223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/23/2017] [Indexed: 11/11/2022] Open
Abstract
The perirhinal cortex (PRh) is a critical mediator of recognition memory, and a wealth of evidence points to impairment in PRh function with age. Despite this evidence, age-related deficits in recognition memory are not consistently observed. This may be partially due to the fact that older animals also have well-established deficits in hippocampal function, and many protocols that assess perirhinal function are also sensitive to hippocampal damage. When using one of these protocols, spontaneous object recognition in an open field, we are able to replicate published age-related deficits using pairs of complex objects. However, when using zero-delay object recognition, a task that is more resistant to the influence of changes in hippocampal function, we find no significant age-related differences in recognition memory in the same animals. These data highlight the importance of the protocol used for testing recognition memory, and may place constraints on the role of the PRh in age-related recognition memory impairment as it is typically tested in much of the literature.
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Affiliation(s)
- Diano F Marrone
- 1Dept. of Psychology, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada.,2McKnight Brain Institute, University of Arizona, Tucson, AZ 85724, USA
| | - Elham Satvat
- 3School of Public Health & Health Systems, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Anuj Patel
- 1Dept. of Psychology, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
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15
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Perkins AE, Vore AS, Lovelock D, Varlinskaya E, Deak T. Late aging alters behavioral sensitivity to ethanol in a sex-specific manner in Fischer 344 rats. Pharmacol Biochem Behav 2018; 175:1-9. [PMID: 30171932 DOI: 10.1016/j.pbb.2018.07.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/23/2018] [Accepted: 07/25/2018] [Indexed: 12/27/2022]
Abstract
Responsiveness to ethanol (EtOH) differs as a function of age. Adolescent rodents are less sensitive than adults to the sedative effects of EtOH, whereas they show enhanced sensitivity to EtOH-induced social facilitation. Late aging is associated with a natural decline in social behavior and aging-related peculiarities in sensitivity to EtOH have been largely unexplored. Whether there are sex differences in the behavioral response to EtOH during late aging remains unknown. Thus, behavioral responses to EtOH in male and female Fischer (F) 344 rats aged 4-5 months (adult) and 19-20 months (aging) were examined. First, the effects of saline and EtOH (0.5 and 0.75 g/kg) on social interaction were assessed. Social investigation and contact behavior were lower in aging animals and higher in females. Interestingly, in aged females, social contact behavior was increased following a 0.5 g/kg EtOH dose, whereas the same dose suppressed social contact in aged males. Behavioral sensitivity to the sedative effects of 3.0 and 3.5 g/kg EtOH was assessed with the loss of righting reflex (LORR) test. Although latency to LORR did not differ as a function of age or sex, aged rats showed significantly greater LORR duration and significantly lower blood ethanol concentrations (BECs) at regaining of the righting reflex relative to adults. In addition, females had a lower LORR duration, regardless of age; no sex differences were evident in BECs at awakening. In a second experiment, blood ethanol concentrations (BECs) over time were assessed following 0.75, 1.5, and 3.0 g/kg EtOH in 3-, 12-, and 18-month-old male and female F344 rats. Aged rats had higher peak BECs following 3.0 g/kg EtOH, whereas few age or sex differences were apparent at lower doses. Taken together, these data indicate that late aging is associated with altered sensitivity to the social facilitating effects and sedative effects of EtOH.
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Affiliation(s)
- Amy E Perkins
- Developmental Exposure to Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY 13902-6000, United States of America
| | - Andrew S Vore
- Developmental Exposure to Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY 13902-6000, United States of America
| | - Dennis Lovelock
- Developmental Exposure to Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY 13902-6000, United States of America
| | - Elena Varlinskaya
- Developmental Exposure to Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY 13902-6000, United States of America
| | - Terrence Deak
- Developmental Exposure to Alcohol Research Center (DEARC), Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY 13902-6000, United States of America.
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16
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Exercise Training Protects Against Aging-Induced Cognitive Dysfunction via Activation of the Hippocampal PGC-1α/FNDC5/BDNF Pathway. Neuromolecular Med 2018; 20:386-400. [DOI: 10.1007/s12017-018-8500-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 06/30/2018] [Indexed: 12/28/2022]
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17
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Gros A, Wang SH. Behavioral tagging and capture: long-term memory decline in middle-aged rats. Neurobiol Aging 2018; 67:31-41. [PMID: 29609080 PMCID: PMC5964067 DOI: 10.1016/j.neurobiolaging.2018.02.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 02/02/2018] [Accepted: 02/24/2018] [Indexed: 02/07/2023]
Abstract
Decline in cognitive functions, including hippocampus-dependent spatial memory, is commonly observed at a later stage of aging (e.g., >20 months old in rodents) and typically studied after a discrete learning event. How normal aging, particularly at an early stage, affects the modulatory aspect of memory persistence is underinvestigated. Previous studies in young animals show that weak, fading memories can last longer if a modulating event, such as spatial novelty, is introduced around memory encoding. This is known as behavioral tagging and capture (BTC). Here, we investigated how early aging (10-13 months old) affects BTC in an appetitive delayed-matching-to-place task. We trained rats when they were young and middle aged and found that novelty facilitated long-term memory persistence in young but not in middle-aged rats. However, re-exposure to the encoded environment after learning improved memory persistence in middle-aged rats. BTC, combined with memory reactivation, facilitated memory persistence through reconsolidation. Our results point toward a weakened tagging and capture mechanism before reduction of plasticity-related proteins at an early stage of aging.
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Affiliation(s)
- Alexandra Gros
- Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, Scotland, UK
| | - Szu-Han Wang
- Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, Scotland, UK; Centre for Cognitive Ageing and Cognitive Epidemiology, The University of Edinburgh, Edinburgh, Scotland, UK.
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18
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Ameen-Ali KE, Wharton SB, Simpson JE, Heath PR, Sharp P, Berwick J. Review: Neuropathology and behavioural features of transgenic murine models of Alzheimer's disease. Neuropathol Appl Neurobiol 2018; 43:553-570. [PMID: 28880417 DOI: 10.1111/nan.12440] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 09/04/2017] [Indexed: 12/11/2022]
Abstract
Our understanding of the underlying biology of Alzheimer's disease (AD) has been steadily progressing; however, this is yet to translate into a successful treatment in humans. The use of transgenic mouse models has helped to develop our understanding of AD, not only in terms of disease pathology, but also with the associated cognitive impairments typical of AD. Plaques and neurofibrillary tangles are often among the last pathological changes in AD mouse models, after neuronal loss and gliosis. There is a general consensus that successful treatments need to be applied before the onset of these pathologies and associated cognitive symptoms. This review discusses the different types of AD mouse models in terms of the temporal progression of the disease, how well they replicate the pathological changes seen in human AD and their cognitive defects. We provide a critical assessment of the behavioural tests used with AD mice to assess cognitive changes and decline, and discuss how successfully they correlate with cognitive impairments in humans with AD. This information is an important tool for AD researchers when deciding on appropriate mouse models, and when selecting measures to assess behavioural and cognitive change.
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Affiliation(s)
- K E Ameen-Ali
- Department of Psychology, University of Sheffield, Sheffield, UK
| | - S B Wharton
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - J E Simpson
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - P R Heath
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - P Sharp
- Department of Psychology, University of Sheffield, Sheffield, UK
| | - J Berwick
- Department of Psychology, University of Sheffield, Sheffield, UK
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19
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Age-related changes in behavior in C57BL/6J mice from young adulthood to middle age. Mol Brain 2016; 9:11. [PMID: 26822304 PMCID: PMC4730600 DOI: 10.1186/s13041-016-0191-9] [Citation(s) in RCA: 315] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 01/20/2016] [Indexed: 01/22/2023] Open
Abstract
Background Aging is considered to be associated with progressive changes in the brain and its associated sensory, motor, and cognitive functions. A large number of studies comparing young and aged animals have reported differences in various behaviors between age-cohorts, indicating behavioral dysfunctions related to aging. However, relatively little is known about behavioral changes from young adulthood to middle age, and the effect of age on behavior during the early stages of life remains to be understood. In order to investigate age-related changes in the behaviors of mice from young adulthood to middle age, we performed a large-scale analysis of the behavioral data obtained from our behavioral test battery involving 1739 C57BL/6J wild-type mice at 2–12 months of age. Results Significant behavioral differences between age groups (2–3-, 4–5-, 6–7-, and 8–12-month-old groups) were found in all the behavioral tests, including the light/dark transition, open field, elevated plus maze, rotarod, social interaction, prepulse inhibition, Porsolt forced swim, tail suspension, Barnes maze, and fear conditioning tests, except for the hot plate test. Compared with the 2–3-month-old group, the 4–5- and 6–7-month-old groups exhibited decreased locomotor activity to novel environments, motor function, acoustic startle response, social behavior, and depression-related behavior, increased prepulse inhibition, and deficits in spatial and cued fear memory. For most behaviors, the 8–12-month-old group showed similar but more pronounced changes in most of these behaviors compared with the younger age groups. Older groups exhibited increased anxiety-like behavior in the light/dark transition test whereas those groups showed seemingly decreased anxiety-like behavior measured by the elevated plus maze test. Conclusions The large-scale analysis of behavioral data from our battery of behavioral tests indicated age-related changes in a wide range of behaviors from young adulthood to middle age in C57BL/6J mice, though these results might have been influenced by possible confounding factors such as the time of day at testing and prior test experience. Our results also indicate that relatively narrow age differences can produce significant behavioral differences during adulthood in mice. These findings provide an insight into our understanding of the neurobiological processes underlying brain function and behavior that are subject to age-related changes in early to middle life. The findings also indicate that age is one of the critical factors to be carefully considered when designing behavioral tests and interpreting behavioral differences that might be induced by experimental manipulations. Electronic supplementary material The online version of this article (doi:10.1186/s13041-016-0191-9) contains supplementary material, which is available to authorized users.
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20
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de Sousa AA, Dos Reis RR, de Lima CM, de Oliveira MA, Fernandes TN, Gomes GF, Diniz DG, Magalhães NM, Diniz CG, Sosthenes MCK, Bento-Torres J, Diniz JAP, Vasconcelos PFDC, Diniz CWP. Three-dimensional morphometric analysis of microglial changes in a mouse model of virus encephalitis: age and environmental influences. Eur J Neurosci 2015; 42:2036-50. [PMID: 25980955 DOI: 10.1111/ejn.12951] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Revised: 04/16/2015] [Accepted: 05/13/2015] [Indexed: 02/05/2023]
Abstract
Many RNA virus CNS infections cause neurological disease. Because Piry virus has a limited human pathogenicity and exercise reduces activation of microglia in aged mice, possible influences of environment and aging on microglial morphology and behavior in mice sublethal encephalitis were investigated. Female albino Swiss mice were raised either in standard (S) or in enriched (EE) cages from age 2 to 6 months (young - Y), or from 2 to 16 months (aged - A). After behavioral tests, mice nostrils were instilled with Piry-virus-infected or with normal brain homogenates. Brain sections were immunolabeled for virus antigens or microglia at 8 days post-infection (dpi), when behavioral changes became apparent, and at 20 and 40 dpi, after additional behavioral testing. Young infected mice from standard (SYPy) and enriched (EYPy) groups showed similar transient impairment in burrowing activity and olfactory discrimination, whereas aged infected mice from both environments (EAPy, SAPy) showed permanent reduction in both tasks. The beneficial effects of an enriched environment were smaller in aged than in young mice. Six-hundred and forty microglial cells, 80 from each group were reconstructed. An unbiased, stereological sampling approach and multivariate statistical analysis were used to search for microglial morphological families. This procedure allowed distinguishing between microglial morphology of infected and control subjects. More severe virus-associated microglial changes were observed in young than in aged mice, and EYPy seem to recover microglial homeostatic morphology earlier than SYPy . Because Piry-virus encephalitis outcomes were more severe in aged mice, it is suggested that the reduced inflammatory response in those individuals may aggravate encephalitis outcomes.
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Affiliation(s)
- Aline A de Sousa
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | - Renata R Dos Reis
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | - Camila M de Lima
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | - Marcus A de Oliveira
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | | | - Giovanni F Gomes
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | - Daniel G Diniz
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | - Nara M Magalhães
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | - Cristovam G Diniz
- Instituto Federal de Educação, Ciência e Tecnologia do Pará, Bragança, Pará, Brazil
| | - Marcia C K Sosthenes
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | - João Bento-Torres
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil
| | - José Antonio P Diniz
- Instituto Evandro Chagas (IEC), Departamento de Arbovirologia e Febres Hemorrágicas, Ananindeua, Pará, Brazil
| | - Pedro F da C Vasconcelos
- Instituto Evandro Chagas (IEC), Departamento de Arbovirologia e Febres Hemorrágicas, Ananindeua, Pará, Brazil
| | - Cristovam Wanderley P Diniz
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Laboratório de Investigações em Neurodegeneração e Infecção no Hospital Universitário João de Barros Barreto, Belém, Pará, Brazil.,Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK
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Puzzo D, Gulisano W, Palmeri A, Arancio O. Rodent models for Alzheimer's disease drug discovery. Expert Opin Drug Discov 2015; 10:703-11. [PMID: 25927677 DOI: 10.1517/17460441.2015.1041913] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
INTRODUCTION Alzheimer's disease (AD) is a neurodegenerative disorder characterized by memory loss and personality changes, leading to dementia. Histopathological hallmarks are represented by aggregates of beta-amyloid peptide (Aβ) in senile plaques and deposition of hyperphosphorylated tau protein in neurofibrillary tangles in the brain. Rare forms of early onset familial Alzheimer's disease are due to gene mutations. This has prompted researchers to develop genetically modified animals that could recapitulate the main features of the disease. The use of these models is complemented by non-genetically modified animals. AREAS COVERED This review summarizes the characteristics of the most used transgenic (Tg) and non-Tg models of AD. The authors have focused on models mainly used in their laboratories including amyloid precursor protein (APP) Tg2576, APP/presenilin 1, 3xAD, single h-Tau, non-Tg mice treated with acute injections of Aβ or tau, and models of physiological aging. EXPERT OPINION Animal models of disease might be very useful for studying the pathophysiology of the disease and for testing new therapeutics in preclinical studies but they do not reproduce the entire clinical features of human AD. When selecting a model, researchers should consider the various factors that might influence the phenotype. They should also consider the timing of testing/treating animals since the age at which each model develops certain aspects of the AD pathology varies.
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Affiliation(s)
- Daniela Puzzo
- University of Catania, Department of Biomedical and Biotechnological Sciences, Section of Physiology , Catania 95100 , Italy
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22
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Luo Y, Zhou J, Li M, Wu P, Hu Z, Ni L, Jin Y, Chen J, Wang F. Reversal of aging-related emotional memory deficits by norepinephrine via regulating the stability of surface AMPA receptors. Aging Cell 2015; 14:170-9. [PMID: 25564942 PMCID: PMC4364829 DOI: 10.1111/acel.12282] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2014] [Indexed: 12/19/2022] Open
Abstract
Aging-related emotional memory deficit is a well-known complication in Alzheimer's disease and normal aging. However, little is known about its molecular mechanism. To address this issue, we examined the role of norepinephrine (NE) and its relevant drug desipramine in the regulation of hippocampal long-term potentiation (LTP), surface expression of AMPA receptor, and associative fear memory in rats. We found that there was a defective regulation of NE content and AMPA receptor trafficking during fear conditioning, which were accompanied by impaired emotional memory and LTP in aged rats. Furthermore, we also found that the exogenous upregulation of NE ameliorated the impairment of LTP and emotional memory via enhancing AMPA receptor trafficking in aged rats, and the downregulation of NE impaired LTP in adult rats. Finally, acute treatment with NE or desipramine rescued the impaired emotional memory in aged rats. These results imply a pivotal role for NE in synaptic plasticity and associative fear memory in aging rats and suggest that desipramine is a potential candidate for treating aging-related emotional memory deficit.
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Affiliation(s)
- Yi Luo
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
| | - Jun Zhou
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
| | - Ming‐Xing Li
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
| | - Peng‐Fei Wu
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
- Key Laboratory of Neurological Diseases (HUST) Ministry of Education of China Wuhan 430030 China
- The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province Wuhan 430030 China
| | - Zhuang‐Li Hu
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
- Key Laboratory of Neurological Diseases (HUST) Ministry of Education of China Wuhan 430030 China
- The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province Wuhan 430030 China
| | - Lan Ni
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
- Key Laboratory of Neurological Diseases (HUST) Ministry of Education of China Wuhan 430030 China
- The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province Wuhan 430030 China
| | - You Jin
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
- Key Laboratory of Neurological Diseases (HUST) Ministry of Education of China Wuhan 430030 China
- The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province Wuhan 430030 China
| | - Jian‐Guo Chen
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
- Key Laboratory of Neurological Diseases (HUST) Ministry of Education of China Wuhan 430030 China
- The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province Wuhan 430030 China
- The Institute of Brain Research Huazhong University of Science and Technology Wuhan 430030 China
| | - Fang Wang
- Department of Pharmacology School of Basic Medicine Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China
- Key Laboratory of Neurological Diseases (HUST) Ministry of Education of China Wuhan 430030 China
- The Key Laboratory for Drug Target Researches and Pharmacodynamic Evaluation of Hubei Province Wuhan 430030 China
- The Institute of Brain Research Huazhong University of Science and Technology Wuhan 430030 China
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Prenderville JA, Kennedy PJ, Dinan TG, Cryan JF. Adding fuel to the fire: the impact of stress on the ageing brain. Trends Neurosci 2015; 38:13-25. [DOI: 10.1016/j.tins.2014.11.001] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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24
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Wheelan N, Webster SP, Kenyon CJ, Caughey S, Walker BR, Holmes MC, Seckl JR, Yau JLW. Short-term inhibition of 11β-hydroxysteroid dehydrogenase type 1 reversibly improves spatial memory but persistently impairs contextual fear memory in aged mice. Neuropharmacology 2014; 91:71-6. [PMID: 25497454 PMCID: PMC4389269 DOI: 10.1016/j.neuropharm.2014.12.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 11/24/2014] [Accepted: 12/02/2014] [Indexed: 02/03/2023]
Abstract
High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design. Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals. Aged mice were treated with UE2316 using a vehicle-controlled crossover design. Short-term UE2316 treatment improves spatial memory in a reversible manner. Contextual fear memory retention was impaired with UE2316. Contextual fear memory effects persisted following reversal of treatment.
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Affiliation(s)
- Nicola Wheelan
- Centre for Cognitive Aging and Cognitive Epidemiology, University of Edinburgh, UK; Endocrinology Unit, BHF Centre for Cardiovascular Science, University of Edinburgh, UK
| | - Scott P Webster
- Endocrinology Unit, BHF Centre for Cardiovascular Science, University of Edinburgh, UK
| | - Christopher J Kenyon
- Endocrinology Unit, BHF Centre for Cardiovascular Science, University of Edinburgh, UK
| | - Sarah Caughey
- Centre for Cognitive Aging and Cognitive Epidemiology, University of Edinburgh, UK; Endocrinology Unit, BHF Centre for Cardiovascular Science, University of Edinburgh, UK
| | - Brian R Walker
- Endocrinology Unit, BHF Centre for Cardiovascular Science, University of Edinburgh, UK
| | - Megan C Holmes
- Centre for Cognitive Aging and Cognitive Epidemiology, University of Edinburgh, UK; Endocrinology Unit, BHF Centre for Cardiovascular Science, University of Edinburgh, UK
| | - Jonathan R Seckl
- Centre for Cognitive Aging and Cognitive Epidemiology, University of Edinburgh, UK; Endocrinology Unit, BHF Centre for Cardiovascular Science, University of Edinburgh, UK
| | - Joyce L W Yau
- Centre for Cognitive Aging and Cognitive Epidemiology, University of Edinburgh, UK; Endocrinology Unit, BHF Centre for Cardiovascular Science, University of Edinburgh, UK.
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25
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Belviranlı M, Okudan N. The effects of Ginkgo biloba extract on cognitive functions in aged female rats: the role of oxidative stress and brain-derived neurotrophic factor. Behav Brain Res 2014; 278:453-61. [PMID: 25446810 DOI: 10.1016/j.bbr.2014.10.032] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 10/20/2014] [Accepted: 10/21/2014] [Indexed: 02/04/2023]
Abstract
The aim of this study was to investigate the effects of Ginkgo biloba extract (GBE) on cognitive functions as well as oxidative stress and brain-derived neurotrophic factor (BDNF) levels in aged female rats. Rats were divided into 4 groups according to age (young vs. aged) and treatment (GBE vs. vehicle). GBE or vehicle was given for 30 d, and a series of behavioral tests were performed. Following behavioral testing, blood samples and brain tissues were obtained for analysis of BDNF, malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHdG), and glutathione levels, and superoxide dismutase activity. Locomotor activity and anxiety levels were lower in the aged rats. Based on Morris water maze probe trial findings, GBE supplementation increased the number of platform crossings in the aged rats. MDA and 8-OHdG levels were lower in the brain tissue, and BDNF levels were higher in plasma in the rates treated with GBE. Based on these findings, we concluded that GBE supplementation improved cognitive functions by decreasing oxidative damage and increasing the BDNF level in aged female rats.
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Affiliation(s)
- Muaz Belviranlı
- Selçuk University, School of Medicine, Department of Physiology, Konya, Turkey.
| | - Nilsel Okudan
- Selçuk University, School of Medicine, Department of Physiology, Konya, Turkey
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26
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Tajiri N, Acosta S, Portillo-Gonzales GS, Aguirre D, Reyes S, Lozano D, Pabon M, Dela Peña I, Ji X, Yasuhara T, Date I, Solomita MA, Antonucci I, Stuppia L, Kaneko Y, Borlongan CV. Therapeutic outcomes of transplantation of amniotic fluid-derived stem cells in experimental ischemic stroke. Front Cell Neurosci 2014; 8:227. [PMID: 25165432 PMCID: PMC4131212 DOI: 10.3389/fncel.2014.00227] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Accepted: 07/23/2014] [Indexed: 01/29/2023] Open
Abstract
Accumulating preclinical evidence suggests the use of amnion as a source of stem cells for investigations of basic science concepts related to developmental cell biology, but also for stem cells’ therapeutic applications in treating human disorders. We previously reported isolation of viable rat amniotic fluid-derived stem (AFS) cells. Subsequently, we recently reported the therapeutic benefits of intravenous transplantation of AFS cells in a rodent model of ischemic stroke. Parallel lines of investigations have provided safety and efficacy of stem cell therapy for treating stroke and other neurological disorders. This review article highlights the need for investigations of mechanisms underlying AFS cells’ therapeutic benefits and discusses lab-to-clinic translational gating items in an effort to optimize the clinical application of the cell transplantation for stroke.
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Affiliation(s)
- Naoki Tajiri
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Sandra Acosta
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Gabriel S Portillo-Gonzales
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Daniela Aguirre
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Stephanny Reyes
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Diego Lozano
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Mibel Pabon
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Ike Dela Peña
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Xunming Ji
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University Beijing, China
| | - Takao Yasuhara
- Department of Neurological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama, Japan
| | - Isao Date
- Department of Neurological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama, Japan
| | - Marianna A Solomita
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Ivana Antonucci
- Laboratory of Molecular Genetics, DISPUTer, School of Medicine and Health Sciences, "G. d 'Annunzio" University Chieti-Pescara, Italy
| | - Liborio Stuppia
- Laboratory of Molecular Genetics, DISPUTer, School of Medicine and Health Sciences, "G. d 'Annunzio" University Chieti-Pescara, Italy
| | - Yuji Kaneko
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
| | - Cesar V Borlongan
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine Tampa, FL, USA
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27
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LEÓN R, PAVÓN N, PENTÓN G, ALMAGUER W, MARÍN J, CRUZ A, LORIGADOS L, BLANCO L, ESTUPIÑÁN B, MERCERON D, MACÍAS L, BERGADO J. Experimental Model of Cerebral Hypoperfusion Produced Memory-learning Deficits, and Modifications in Gene Expression. ACTA BIOLÓGICA COLOMBIANA 2014. [DOI: 10.15446/abc.v20n1.40976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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28
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Puzzo D, Lee L, Palmeri A, Calabrese G, Arancio O. Behavioral assays with mouse models of Alzheimer's disease: practical considerations and guidelines. Biochem Pharmacol 2014; 88:450-67. [PMID: 24462904 PMCID: PMC4014001 DOI: 10.1016/j.bcp.2014.01.011] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 01/09/2014] [Accepted: 01/09/2014] [Indexed: 12/14/2022]
Abstract
In Alzheimer's disease (AD) basic research and drug discovery, mouse models are essential resources for uncovering biological mechanisms, validating molecular targets and screening potential compounds. Both transgenic and non-genetically modified mouse models enable access to different types of AD-like pathology in vivo. Although there is a wealth of genetic and biochemical studies on proposed AD pathogenic pathways, as a disease that centrally features cognitive failure, the ultimate readout for any interventions should be measures of learning and memory. This is particularly important given the lack of knowledge on disease etiology - assessment by cognitive assays offers the advantage of targeting relevant memory systems without requiring assumptions about pathogenesis. A multitude of behavioral assays are available for assessing cognitive functioning in mouse models, including ones specific for hippocampal-dependent learning and memory. Here we review the basics of available transgenic and non-transgenic AD mouse models and detail three well-established behavioral tasks commonly used for testing hippocampal-dependent cognition in mice - contextual fear conditioning, radial arm water maze and Morris water maze. In particular, we discuss the practical considerations, requirements and caveats of these behavioral testing paradigms.
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Affiliation(s)
- Daniela Puzzo
- Department of Bio-Medical Sciences - Section of Physiology, University of Catania, Viale A. Doria 6, Catania 95125, Italy
| | - Linda Lee
- Department of Pathology & Cell Biology, The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, P&S #12-420D, 630W 168th Street, New York, NY 10032, USA
| | - Agostino Palmeri
- Department of Bio-Medical Sciences - Section of Physiology, University of Catania, Viale A. Doria 6, Catania 95125, Italy
| | - Giorgio Calabrese
- Department of Pharmacy, Federico II University, Via D. Montesano 49, Naples 80131, Italy
| | - Ottavio Arancio
- Department of Pathology & Cell Biology, The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, P&S #12-420D, 630W 168th Street, New York, NY 10032, USA.
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29
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Justel N, Mustaca A, Boccia M, Ruetti E. Incentive relativity in middle aged rats. Neurosci Lett 2014; 559:122-6. [PMID: 24315974 DOI: 10.1016/j.neulet.2013.11.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 11/22/2013] [Accepted: 11/26/2013] [Indexed: 11/26/2022]
Abstract
Response to a reinforcer is affected by prior experience with different reward values of that reward, a phenomenon known as incentive relativity. Two different procedures to study this phenomenon are the incentive downshift (ID) and the consummatory anticipatory negative contrast (cANC), the former is an emotional-cognitive protocol and the latter cognitive one. Aged rodents, as also well described in aged humans, exhibit alterations in cognitive functions. The main goal of this work was to evaluate the effect of age in the incentive' assessment using these two procedures. The results indicated that aged rats had an adequate assessment of the rewards but their performance is not completely comparable to that of young subjects. They recover faster from the ID and they had a cognitive impairment in the cANC. The results are discussed in relation to age-related changes in memory and emotion.
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Affiliation(s)
- N Justel
- Laboratorio de Psicología Experimental y Aplicada, Instituto de Investigaciones Médicas (IDIM), UBA-CONICET, Argentina
| | - A Mustaca
- Laboratorio de Psicología Experimental y Aplicada, Instituto de Investigaciones Médicas (IDIM), UBA-CONICET, Argentina; Universidad Abierta Interamericana (UAI), Argentina
| | - M Boccia
- Lab. de los Procesos de Memoria, Fac. de Farmacia y Bioquímica, UBA-CONICET, Argentina
| | - E Ruetti
- Laboratorio de Psicología Experimental y Aplicada, Instituto de Investigaciones Médicas (IDIM), UBA-CONICET, Argentina.
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30
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Viana L, Lima C, Oliveira M, Borges R, Cardoso T, Almeida I, Diniz D, Bento-Torres J, Pereira A, Batista-de-Oliveira M, Lopes A, Silva R, Abadie-Guedes R, Amâncio dos Santos A, Lima D, Vasconcelos P, Cunningham C, Guedes R, Picanço-Diniz C. Litter size, age-related memory impairments, and microglial changes in rat dentate gyrus: Stereological analysis and three dimensional morphometry. Neuroscience 2013; 238:280-96. [DOI: 10.1016/j.neuroscience.2013.02.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Revised: 02/12/2013] [Accepted: 02/12/2013] [Indexed: 10/27/2022]
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31
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Curcumin improves spatial memory and decreases oxidative damage in aged female rats. Biogerontology 2013; 14:187-96. [DOI: 10.1007/s10522-013-9422-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 04/03/2013] [Indexed: 11/26/2022]
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32
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Sallaberry C, Nunes F, Costa MS, Fioreze GT, Ardais AP, Botton PHS, Klaudat B, Forte T, Souza DO, Elisabetsky E, Porciúncula LO. Chronic caffeine prevents changes in inhibitory avoidance memory and hippocampal BDNF immunocontent in middle-aged rats. Neuropharmacology 2013; 64:153-9. [PMID: 22841916 DOI: 10.1016/j.neuropharm.2012.07.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Revised: 07/03/2012] [Accepted: 07/04/2012] [Indexed: 12/20/2022]
Abstract
Beneficial effects of caffeine on memory processes have been observed in animal models relevant to neurodegenerative diseases and aging, although the underlying mechanisms remain unknown. Because brain-derived neurotrophic factor (BDNF) is associated with memory formation and BDNF's actions are modulated by adenosine receptors, the molecular targets for the psychostimulant actions of caffeine, we here compare the effects of chronic caffeine (1 mg/mL drinking solution for 30 days) on short- and long term memory and on levels of hippocampal proBDNF, mature BDNF, TrkB and CREB in young (3 month old) and middle-aged (12 month old) rats. Caffeine treatment substantially reduced i) age-related impairments in the two types of memory in an inhibitory avoidance paradigm, and ii) parallel increases in hippocampal BDNF levels. In addition, chronic caffeine increased proBDNF and CREB concentrations, and decreased TrkB levels, in hippocampus regardless of age. These data provide new evidence in favor of the hypothesis that modifications in BDNF and related proteins in the hippocampus contribute to the pro-cognitive effects of caffeine on age-associated losses in memory encoding. This article is part of a Special Issue entitled 'Cognitive Enhancers'.
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Affiliation(s)
- Cássia Sallaberry
- Laboratory of Studies on the Purinergic System, Department of Biochemistry, Health and Basic Sciences Institute, Federal University of Rio Grande do Sul, Rua Ramiro Barcelos, 2600-anexo, Porto Alegre, RS 90035 003, Brazil
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33
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Palmeri A, Privitera L, Giunta S, Loreto C, Puzzo D. Inhibition of phosphodiesterase-5 rescues age-related impairment of synaptic plasticity and memory. Behav Brain Res 2012; 240:11-20. [PMID: 23174209 DOI: 10.1016/j.bbr.2012.10.060] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 10/26/2012] [Accepted: 10/30/2012] [Indexed: 12/14/2022]
Abstract
Aging is characterized by a progressive cognitive decline that leads to memory impairment. Because the cyclic nucleotide cascade is essential for the integrity of synaptic function and memory, and it is down-regulated during aging and in neurodegenerative disorders, we investigated whether an increase in cGMP levels might rescue age-related synaptic and memory deficits in mice. We demonstrated that acute perfusion with the phosphodiesterase-5 inhibitor sildenafil (50 nM) ameliorated long-term potentiation in hippocampal slices from 26-30-month-old mice. Moreover, chronic intraperitoneal injection of sildenafil (3mg/kg for 3 weeks) improved age-related spatial learning and reference memory as tested by the Morris Water Maze, and recognition memory as tested by the Object Recognition Test. Finally, sildenafil restored central cAMP responsive element-binding protein (CREB) phosphorylation, which is crucial for synaptic plasticity and memory. Our data suggest that inhibition of phosphodiesterase-5 may be beneficial to treat age-related cognitive dysfunction in a physiological mouse model of aging.
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Affiliation(s)
- Agostino Palmeri
- Department of Bio-Medical Sciences - Section of Physiology, University of Catania, Catania, 95125, Italy
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34
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Age and sex affect spatial and emotional behaviors in rats: the role of repeated elevated plus maze test. Neuroscience 2012; 227:1-9. [PMID: 23018000 DOI: 10.1016/j.neuroscience.2012.09.036] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 09/13/2012] [Accepted: 09/14/2012] [Indexed: 11/21/2022]
Abstract
The main objective of the study was to investigate the effects of age and sex differences on locomotor activity, learning and memory in rats. Another objective was to investigate whether repeated elevated plus maze tests induce anxiety in rats. Eighty Wistar rats were divided into eight groups according to their sex, age and anxiety status. Locomotor activity was assessed in open field. Repeated anxiety tests were performed in elevated plus maze. Spatial learning and memory were evaluated with the Morris water maze. All behavioral tests were recorded online and analyzed offline with an analytical software. Exploratory behavior was lower in anxiety-induced rats. Male rats had lower anxiety levels, locomotor activity and exploratory behavior compared to females. During the training period of Morris water maze latency to find platform, total distance traveled and average swimming speed decreased in all groups with repeated tests and young rats generally were faster than aged rats. During the probe trial, although the number of platform crossings was not affected, time spent in the platform zone was higher in the young groups compared to the aged groups. In conclusion, age and sex affect locomotor activity, learning and memory in different aspects.
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35
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Gámiz F, Gallo M. Spontaneous object recognition memory in aged rats: Complexity versus similarity. Learn Mem 2012; 19:444-8. [PMID: 22984281 DOI: 10.1101/lm.027003.112] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Previous work on the effect of aging on spontaneous object recognition (SOR) memory tasks in rats has yielded controversial results. Although the results at long-retention intervals are consistent, conflicting results have been reported at shorter delays. We have assessed the potential relevance of the type of object used in the performance of aged rats in SOR tasks. Using standard objects, 24-mo-old rats did not exhibit retention impairment at a 1-h delay. At this retention interval no differences between young and old rats were found in a high-similarity SOR task, but aged rats exhibited deficits when clearly different complex forms were applied.
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Affiliation(s)
- Fernando Gámiz
- Department of Psychobiology, Institute of Neurosciences, Center for Biomedical Research (CIBM), University of Granada, Granada 18071, Spain.
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36
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Foster TC, Defazio RA, Bizon JL. Characterizing cognitive aging of spatial and contextual memory in animal models. Front Aging Neurosci 2012; 4:12. [PMID: 22988436 PMCID: PMC3439636 DOI: 10.3389/fnagi.2012.00012] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 05/15/2012] [Indexed: 11/30/2022] Open
Abstract
Episodic memory, especially memory for contextual or spatial information, is particularly vulnerable to age-related decline in humans and animal models of aging. The continuing improvement of virtual environment technology for testing humans signifies that widely used procedures employed in the animal literature for examining spatial memory could be developed for examining age-related cognitive decline in humans. The current review examines cross species considerations for implementing these tasks and translating findings across different levels of analysis. The specificity of brain systems as well as gaps in linking human and animal laboratory models is discussed.
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Affiliation(s)
- Thomas C Foster
- Department of Neuroscience, Evelyn F. and William L. McKnight Brain Institute, University of Florida Gainesville, FL, USA
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37
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Yau JLW, Seckl JR. Local amplification of glucocorticoids in the aging brain and impaired spatial memory. Front Aging Neurosci 2012; 4:24. [PMID: 22952463 PMCID: PMC3430012 DOI: 10.3389/fnagi.2012.00024] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 08/02/2012] [Indexed: 12/24/2022] Open
Abstract
The hippocampus is a prime target for glucocorticoids (GCs) and a brain structure particularly vulnerable to aging. Prolonged exposure to excess GCs compromises hippocampal electrophysiology, structure, and function. Blood GC levels tend to increase with aging and correlate with impaired spatial memory in aging rodents and humans. The magnitude of GC action within tissues depends not only on levels of steroid hormone that enter the cells from the periphery and the density of intracellular receptors but also on the local metabolism of GCs by 11β-hydroxysteroid dehydrogenases (11β-HSD). The predominant isozyme in the adult brain, 11β-HSD1, locally regenerates active GCs from inert 11-keto forms thus amplifying GC levels within specific target cells including in the hippocampus and cortex. Aging associates with elevated hippocampal and neocortical 11β-HSD1 and impaired spatial learning while deficiency of 11β-HSD1 in knockout (KO) mice prevents the emergence of cognitive decline with age. Furthermore, short-term pharmacological inhibition of 11β-HSD1 in already aged mice reverses spatial memory impairments. Here, we review research findings that support a key role for GCs with special emphasis on their intracellular regulation by 11β-HSD1 in the emergence of spatial memory deficits with aging, and discuss the use of 11β-HSD1 inhibitors as a promising novel treatment in ameliorating/improving age-related memory impairments.
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Affiliation(s)
- Joyce L W Yau
- Centre for Cognitive Ageing and Cognitive Epidemiology and Endocrinology Unit, Centre for Cardiovascular Science, The Queen's Medical Research Institute, University of Edinburgh Edinburgh, UK
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38
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Tajiri N, Acosta S, Glover LE, Bickford PC, Jacotte Simancas A, Yasuhara T, Date I, Solomita MA, Antonucci I, Stuppia L, Kaneko Y, Borlongan CV. Intravenous grafts of amniotic fluid-derived stem cells induce endogenous cell proliferation and attenuate behavioral deficits in ischemic stroke rats. PLoS One 2012; 7:e43779. [PMID: 22912905 PMCID: PMC3422299 DOI: 10.1371/journal.pone.0043779] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Accepted: 07/25/2012] [Indexed: 01/11/2023] Open
Abstract
We recently reported isolation of viable rat amniotic fluid-derived stem (AFS) cells [1]. Here, we tested the therapeutic benefits of AFS cells in a rodent model of ischemic stroke. Adult male Sprague-Dawley rats received a 60-minute middle cerebral artery occlusion (MCAo). Thirty-five days later, animals exhibiting significant motor deficits received intravenous transplants of rat AFS cells or vehicle. At days 60–63 post-MCAo, significant recovery of motor and cognitive function was seen in stroke animals transplanted with AFS cells compared to vehicle-infused stroke animals. Infarct volume, as revealed by hematoxylin and eosin (H&E) staining, was significantly reduced, coupled with significant increments in the cell proliferation marker, Ki67, and the neuronal marker, MAP2, in the dentate gyrus (DG) [2] and the subventricular zone (SVZ) of AFS cell-transplanted stroke animals compared to vehicle-infused stroke animals. A significantly higher number of double-labeled Ki67/MAP2-positive cells and a similar trend towards increased Ki67/MAP2 double-labeling were observed in the DG and SVZ of AFS cell-transplanted stroke animals, respectively, compared to vehicle-infused stroke animals. This study reports the therapeutic potential of AFS cell transplantation in stroke animals, possibly via enhancement of endogenous repair mechanisms.
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Affiliation(s)
- Naoki Tajiri
- Department of Neurosurgery and Brain Repair, Center of Excellence for Aging and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, Florida, United States of America
| | - Sandra Acosta
- Department of Neurosurgery and Brain Repair, Center of Excellence for Aging and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, Florida, United States of America
| | - Loren E. Glover
- Department of Neurosurgery and Brain Repair, Center of Excellence for Aging and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, Florida, United States of America
| | - Paula C. Bickford
- Department of Neurosurgery and Brain Repair, Center of Excellence for Aging and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, Florida, United States of America
| | - Alejandra Jacotte Simancas
- Departamento de Psicobiologia y Metodologia de las Cièncias de la Salud, Universidad Autónoma de Barcelona, Barcelona, Spain
| | - Takao Yasuhara
- Department of Neurological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Isao Date
- Department of Neurological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Marianna A. Solomita
- Department of Neurosurgery and Brain Repair, Center of Excellence for Aging and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, Florida, United States of America
- Department of Biomedical Sciences, G. d'Annunzio University, Chieti-Pescara, Italy
- Department of Neuroscience and Imaging, School of Advanced Studies G.d'Annunzio, Chieti University and Stem TeCh Group, Aging Research Center, Chieti- Pescara, Italy
| | - Ivana Antonucci
- Department of Biomedical Sciences, G. d'Annunzio University, Chieti-Pescara, Italy
- Department of Neuroscience and Imaging, School of Advanced Studies G.d'Annunzio, Chieti University and Stem TeCh Group, Aging Research Center, Chieti- Pescara, Italy
| | - Liborio Stuppia
- Department of Biomedical Sciences, G. d'Annunzio University, Chieti-Pescara, Italy
- Department of Neuroscience and Imaging, School of Advanced Studies G.d'Annunzio, Chieti University and Stem TeCh Group, Aging Research Center, Chieti- Pescara, Italy
| | - Yuji Kaneko
- Department of Neurosurgery and Brain Repair, Center of Excellence for Aging and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, Florida, United States of America
| | - Cesar V. Borlongan
- Department of Neurosurgery and Brain Repair, Center of Excellence for Aging and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, Florida, United States of America
- * E-mail:
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Melo P, Magalhães A, Alves CJ, Tavares MA, de Sousa L, Summavielle T, Moradas-Ferreira P. Methamphetamine mimics the neurochemical profile of aging in rats and impairs recognition memory. Neurotoxicology 2012; 33:491-9. [PMID: 22433442 DOI: 10.1016/j.neuro.2012.03.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 03/03/2012] [Accepted: 03/04/2012] [Indexed: 12/13/2022]
Abstract
Brain neurochemistry and cognition performance are thought to decline with age. Accumulating data indicate that similar events occur after prolonged methamphetamine (MA) exposure. Using the rat as a model, the present study was designed to uncover common alteration patterns in brain neurochemistry and memory performance between aging and prolonged MA exposure. To this end, animals were treated with a chronic binge MA administration paradigm (20mg/kg/day from postnatal day 91 to 100). Three-age control groups received isovolumetric saline treatment and were tested at the MA age-matched period, and at 12 and 20 months. We observed that both MA and aged animals presented a long, but not short, time impairment in novelty preference and an increased anxiety-like behavior. Neurochemical analysis indicated similar MA- and age-related impairments in dopamine, serotonin and metabolites in the striatum, prefrontal cortex and hippocampus. Thus, the present data illustrate that MA may be used to mimic age-related effects on neurotransmitter systems and advocate MA treatment as a feasible animal model to study neuronal processes associated with aging.
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Affiliation(s)
- Pedro Melo
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.
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Foster TC. Dissecting the age-related decline on spatial learning and memory tasks in rodent models: N-methyl-D-aspartate receptors and voltage-dependent Ca2+ channels in senescent synaptic plasticity. Prog Neurobiol 2012; 96:283-303. [PMID: 22307057 DOI: 10.1016/j.pneurobio.2012.01.007] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 01/09/2012] [Accepted: 01/19/2012] [Indexed: 10/14/2022]
Abstract
In humans, heterogeneity in the decline of hippocampal-dependent episodic memory is observed during aging. Rodents have been employed as models of age-related cognitive decline and the spatial water maze has been used to show variability in the emergence and extent of impaired hippocampal-dependent memory. Impairment in the consolidation of intermediate-term memory for rapidly acquired and flexible spatial information emerges early, in middle-age. As aging proceeds, deficits may broaden to include impaired incremental learning of a spatial reference memory. The extent and time course of impairment has been be linked to senescence of calcium (Ca²⁺) regulation and Ca²⁺-dependent synaptic plasticity mechanisms in region CA1. Specifically, aging is associated with altered function of N-methyl-D-aspartate receptors (NMDARs), voltage-dependent Ca²⁺ channels (VDCCs), and ryanodine receptors (RyRs) linked to intracellular Ca²⁺ stores (ICS). In young animals, NMDAR activation induces long-term potentiation of synaptic transmission (NMDAR-LTP), which is thought to mediate the rapid consolidation of intermediate-term memory. Oxidative stress, starting in middle-age, reduces NMDAR function. In addition, VDCCs and ICS can actively inhibit NMDAR-dependent LTP and oxidative stress enhances the role of VDCC and RyR-ICS in regulating synaptic plasticity. Blockade of L-type VDCCs promotes NMDAR-LTP and memory in older animals. Interestingly, pharmacological or genetic manipulations to reduce hippocampal NMDAR function readily impair memory consolidation or rapid learning, generally leaving incremental learning intact. Finally, evidence is mounting to indicate a role for VDCC-dependent synaptic plasticity in associative learning and the consolidation of remote memories. Thus, VDCC-dependent synaptic plasticity and extrahippocampal systems may contribute to incremental learning deficits observed with advanced aging.
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Affiliation(s)
- Thomas C Foster
- Department of Neuroscience, Evelyn F. and William L. McKnight Brain Institute, University of Florida, PO Box 100244, Gainesville, FL 32610-0244, USA. ,
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