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Kundu P, Zimmerman B, Perez R, Whitlow CT, Cline JM, Olson JD, Andrews RN, Raber J. Apolipoprotein E levels in the amygdala and prefrontal cortex predict relative regional brain volumes in irradiated Rhesus macaques. Sci Rep 2021; 11:22130. [PMID: 34764354 PMCID: PMC8585884 DOI: 10.1038/s41598-021-01480-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 10/26/2021] [Indexed: 01/20/2023] Open
Abstract
In the brain, apolipoprotein E (apoE) plays an important role in lipid transport and response to environmental and age-related challenges, including neuronal repair following injury. While much has been learned from radiation studies in rodents, a gap in our knowledge is how radiation might affect the brain in primates. This is important for assessing risk to the brain following radiotherapy as part of cancer treatment or environmental radiation exposure as part of a nuclear accident, bioterrorism, or a nuclear attack. In this study, we investigated the effects of ionizing radiation on brain volumes and apoE levels in the prefrontal cortex, amygdala, and hippocampus of Rhesus macaques that were part of the Nonhuman Primate Radiation Survivor Cohort at the Wake Forest University. This unique cohort is composed of Rhesus macaques that had previously received single total body doses of 6.5-8.05 Gy of ionizing radiation. Regional apoE levels predicted regional volume in the amygdala and the prefrontal cortex. In addition, apoE levels in the amygdala, but not the hippocampus, strongly predicted relative hippocampal volume. Finally, radiation dose negatively affected relative hippocampal volume when apoE levels in the amygdala were controlled for, suggesting a protective compensatory role of regional apoE levels following radiation exposure. In a supplementary analysis, there also was a robust positive relationship between the neuroprotective protein α-klotho and apoE levels in the amygdala, further supporting the potentially protective role of apoE. Increased understanding of the effects of IR in the primate brain and the role of apoE in the irradiated brain could inform future therapies to mitigate the adverse effects of IR on the CNS.
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Affiliation(s)
- Payel Kundu
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA
| | - Benjamin Zimmerman
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA
- Advanced Imaging Research Center, Oregon Health and Science University, Portland, OR, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ruby Perez
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA
| | - Christopher T Whitlow
- Department of Radiology, Radiology Informatics & Image Processing Laboratory (RIIPL), Wake Forest University, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - J Mark Cline
- Department of Radiology, Radiology Informatics & Image Processing Laboratory (RIIPL), Wake Forest University, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - John D Olson
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Rachel N Andrews
- Department of Radiology, Radiology Informatics & Image Processing Laboratory (RIIPL), Wake Forest University, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA.
- Division of Neuroscience, Departments of Neurology and Radiation Medicine, ONPRC, Oregon Health and Science University, Portland, OR, USA.
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Skilling QM, Eniwaye B, Clawson BC, Shaver J, Ognjanovski N, Aton SJ, Zochowski M. Acetylcholine-gated current translates wake neuronal firing rate information into a spike timing-based code in Non-REM sleep, stabilizing neural network dynamics during memory consolidation. PLoS Comput Biol 2021; 17:e1009424. [PMID: 34543284 PMCID: PMC8483332 DOI: 10.1371/journal.pcbi.1009424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 09/30/2021] [Accepted: 09/06/2021] [Indexed: 11/19/2022] Open
Abstract
Sleep is critical for memory consolidation, although the exact mechanisms mediating this process are unknown. Combining reduced network models and analysis of in vivo recordings, we tested the hypothesis that neuromodulatory changes in acetylcholine (ACh) levels during non-rapid eye movement (NREM) sleep mediate stabilization of network-wide firing patterns, with temporal order of neurons’ firing dependent on their mean firing rate during wake. In both reduced models and in vivo recordings from mouse hippocampus, we find that the relative order of firing among neurons during NREM sleep reflects their relative firing rates during prior wake. Our modeling results show that this remapping of wake-associated, firing frequency-based representations is based on NREM-associated changes in neuronal excitability mediated by ACh-gated potassium current. We also show that learning-dependent reordering of sequential firing during NREM sleep, together with spike timing-dependent plasticity (STDP), reconfigures neuronal firing rates across the network. This rescaling of firing rates has been reported in multiple brain circuits across periods of sleep. Our model and experimental data both suggest that this effect is amplified in neural circuits following learning. Together our data suggest that sleep may bias neural networks from firing rate-based towards phase-based information encoding to consolidate memories. We show that neuromodulatory changes during non-rapid eye movement (NREM) sleep generate stable spike timing relationships between neurons, the ordering of which reflects the neurons’ relative firing rates during wake. Learning-dependent ordering of firing in the hippocampus during NREM, acting in tandem with spike timing-dependent plasticity, reconfigures neuronal firing rates across the hippocampal network. This “rescaling” of neuronal firing rates has recently been reported in multiple brain circuits across periods of sleep. Together, our results suggest that the brain is remapping frequency-biased representations of information formed during wake into timing biased-representations during NREM sleep.
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Affiliation(s)
- Quinton M Skilling
- Biophysics Program, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Bolaji Eniwaye
- Applied Physics Program, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Brittany C Clawson
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - James Shaver
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Nicolette Ognjanovski
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Sara J Aton
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Michal Zochowski
- Biophysics Program, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Physics, University of Michigan, Ann Arbor, Michigan, United States of America
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Bernaud VE, Hiroi R, Poisson ML, Castaneda AJ, Kirshner ZZ, Gibbs RB, Bimonte-Nelson HA. Age Impacts the Burden That Reference Memory Imparts on an Increasing Working Memory Load and Modifies Relationships With Cholinergic Activity. Front Behav Neurosci 2021; 15:610078. [PMID: 33643006 PMCID: PMC7902531 DOI: 10.3389/fnbeh.2021.610078] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 01/07/2021] [Indexed: 11/19/2022] Open
Abstract
Rodent aging research often utilizes spatial mazes, such as the water radial-arm-maze (WRAM), to evaluate cognition. The WRAM can simultaneously measure spatial working and reference memory, wherein these two memory types are often represented as orthogonal. There is evidence, however, that these two memory forms yield interference at a high working memory load. The current study systematically evaluated whether the presence of a reference memory component impacts handling of an increasing working memory load. Young and aged female rats were tested to assess whether aging impacts this relationship. Cholinergic projections from the basal forebrain to the hippocampus and cortex can affect cognitive outcomes, and are negatively impacted by aging. To evaluate whether age-related changes in working and reference memory profiles are associated with cholinergic functioning, we assessed choline acetyltransferase activity in these behaviorally-tested rats. Results showed that young rats outperformed aged rats on a task testing solely working memory. The addition of a reference memory component deteriorated the ability to handle an increasing working memory load, such that young rats performed similar to their aged counterparts. Aged rats also had challenges when reference memory was present, but in a different context. Specifically, aged rats had difficulty remembering which reference memory arms they had entered within a session, compared to young rats. Further, aged rats that excelled in reference memory also excelled in working memory when working memory demand was high, a relationship not seen in young rats. Relationships between cholinergic activity and maze performance differed by age in direction and brain region, reflecting the complex role that the cholinergic system plays in memory and attentional processes across the female lifespan. Overall, the addition of a reference memory requirement detrimentally impacted the ability to handle working memory information across young and aged timepoints, especially when the working memory challenge was high; these age-related deficits manifested differently with the addition of a reference memory component. This interplay between working and reference memory provides insight into the multiple domains necessary to solve complex cognitive tasks, potentially improving the understanding of complexities of age- and disease- related memory failures and optimizing their respective treatments.
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Affiliation(s)
- Victoria E Bernaud
- Department of Psychology, Arizona State University, Tempe, AZ, United States.,Arizona Alzheimer's Consortium, Phoenix, AZ, United States
| | - Ryoko Hiroi
- Department of Psychology, Arizona State University, Tempe, AZ, United States.,Arizona Alzheimer's Consortium, Phoenix, AZ, United States
| | - Mallori L Poisson
- Department of Psychology, Arizona State University, Tempe, AZ, United States.,Arizona Alzheimer's Consortium, Phoenix, AZ, United States
| | - Arthur J Castaneda
- Department of Psychology, Arizona State University, Tempe, AZ, United States.,Arizona Alzheimer's Consortium, Phoenix, AZ, United States
| | - Ziv Z Kirshner
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, PA, United States
| | - Robert B Gibbs
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, PA, United States
| | - Heather A Bimonte-Nelson
- Department of Psychology, Arizona State University, Tempe, AZ, United States.,Arizona Alzheimer's Consortium, Phoenix, AZ, United States
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Blockade of the M1 muscarinic acetylcholine receptors impairs eyeblink serial feature-positive discrimination learning in mice. PLoS One 2020; 15:e0237451. [PMID: 32790748 PMCID: PMC7425847 DOI: 10.1371/journal.pone.0237451] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 07/27/2020] [Indexed: 11/19/2022] Open
Abstract
The serial feature-positive discrimination task requires the subjects to respond differentially to the identical stimulus depending on the temporal context given by a preceding cue stimulus. In the present study, we examined the involvement of the M1 muscarinic acetylcholine receptors using a selective M1 antagonist VU0255035 in the serial feature-positive discrimination task of eyeblink conditioning in mice. In this task, mice received a 2-s light stimulus as the conditional cue 5 or 6 s before the presentation of a 350-ms tone conditioned stimulus (CS) paired with a 100-ms peri-orbital electrical shock (cued trials), while they did not receive the cue before the presentation of the CS alone (non-cued trials). Each day mice randomly received 30 cued and 30 non-cued trials. We found that VU0255035 impaired acquisition of the conditional discrimination as well as the overall acquisition of the conditioned response (CR) and diminished the difference in onset latency of the CR between the cued and non-cued trials. VU0255035 administration to the control mice after sufficient learning did not impair the pre-acquired conditional discrimination or the CR expression itself. These effects of VU0255035 were almost similar to those with the scopolamine in our previous study, suggesting that among the several types of muscarinic acetylcholine receptors, the M1 receptors may play an important role in the acquisition of the conditional discrimination memory but not in mediating the discrimination itself after the memory had formed in the eyeblink serial feature-positive discrimination learning.
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Tariq A, Javed S, Farhat SM, Ahmed T. Effects of curcuminoids on cognitive deficits in young audiovisually overstimulated mice. FOOD BIOSCI 2020. [DOI: 10.1016/j.fbio.2020.100565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Wu Q, Cao Y, Liu M, Liu F, Brantner AH, Yang Y, Wei Y, Zhou Y, Wang Z, Ma L, Wang F, Pei H, Li H. Traditional Chinese Medicine Shenmayizhi Decoction Ameliorates Memory And Cognitive Impairment Induced By Scopolamine Via Preventing Hippocampal Cholinergic Dysfunction In Rats. Neuropsychiatr Dis Treat 2019; 15:3167-3176. [PMID: 31814724 PMCID: PMC6858809 DOI: 10.2147/ndt.s214976] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 08/23/2019] [Indexed: 12/23/2022] Open
Abstract
PURPOSE Clinical trials have illustrated that Shenmayizhi decoction (SMYZ) could improve the cognitive functions in patients with dementia. However, the mechanism needs to be explored. METHODS Fifty adult male rats (Wistar strain) were divided into five groups equally and randomly, including control, model, and SMYZ of low dose, medium dose and high dose. Rats in each group received a daily gavage of respective treatment. Rats in control and model group were administrated by the same volume of distilled water. Memory impairment was induced by intraperitoneal administration of scopolamine (0.7 mg/kg) for 5 continuous days. Four weeks later, Morris water maze (MWM) was performed to evaluate the spatial memory in all rats. Then, rats were sacrificed and the hippocampus was removed for further tests. Furthermore, Western blot analysis was employed to assess the levels of acetylcholine M1 receptor (M1), acetylcholine M2 receptor (M2), acetylcholinesterase (AChE) and cholineacetyltransferase (ChAT). AChE and ChAT activities were determined. RESULTS The SMYZ decoction significantly improved behavioral performance of rats in high dose. The SMYZ decoction in three doses exhibited anti-acetylcholinesterase activity. In addition, a high dose of SMYZ promoted ChAT activity. Moreover, a high dose of SMYZ increased the level of ChAT and declined the level of AChE assessed by Western blotting. Besides, an increased level of M1 receptor was found after treatment. CONCLUSION Shenmayizhi decoction could mitigate scopolamine-induced cognitive deficits through the preventative effect on cholinergic system dysfunction.
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Affiliation(s)
- Qiong Wu
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
- Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing100078, People’s Republic of China
| | - Yu Cao
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Meixia Liu
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Fang Liu
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Adelheid H Brantner
- Department of Pharmacognosy, Institute of Pharmaceutical Sciences, University of Graz, Graz, Austria
| | - Yang Yang
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Yun Wei
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Yu Zhou
- Department of Polymer Chemistry, Zernike Institute for Advanced Materials, Groningen9747 AG, The Netherlands
| | - Zhiyong Wang
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Lina Ma
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Feixue Wang
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Hui Pei
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
| | - Hao Li
- Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing100091, People’s Republic of China
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Febo M, Foster TC. Preclinical Magnetic Resonance Imaging and Spectroscopy Studies of Memory, Aging, and Cognitive Decline. Front Aging Neurosci 2016; 8:158. [PMID: 27468264 PMCID: PMC4942756 DOI: 10.3389/fnagi.2016.00158] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 06/16/2016] [Indexed: 01/14/2023] Open
Abstract
Neuroimaging provides for non-invasive evaluation of brain structure and activity and has been employed to suggest possible mechanisms for cognitive aging in humans. However, these imaging procedures have limits in terms of defining cellular and molecular mechanisms. In contrast, investigations of cognitive aging in animal models have mostly utilized techniques that have offered insight on synaptic, cellular, genetic, and epigenetic mechanisms affecting memory. Studies employing magnetic resonance imaging and spectroscopy (MRI and MRS, respectively) in animal models have emerged as an integrative set of techniques bridging localized cellular/molecular phenomenon and broader in vivo neural network alterations. MRI methods are remarkably suited to longitudinal tracking of cognitive function over extended periods permitting examination of the trajectory of structural or activity related changes. Combined with molecular and electrophysiological tools to selectively drive activity within specific brain regions, recent studies have begun to unlock the meaning of fMRI signals in terms of the role of neural plasticity and types of neural activity that generate the signals. The techniques provide a unique opportunity to causally determine how memory-relevant synaptic activity is processed and how memories may be distributed or reconsolidated over time. The present review summarizes research employing animal MRI and MRS in the study of brain function, structure, and biochemistry, with a particular focus on age-related cognitive decline.
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Affiliation(s)
- Marcelo Febo
- Department of Psychiatry, William L. and Evelyn F. McKnight Brain Institute, University of Florida Gainesville, FL, USA
| | - Thomas C Foster
- Department of Neuroscience, William L. and Evelyn F. McKnight Brain Institute, University of Florida Gainesville, FL, USA
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Haley GE, Yeiser L, Olsen RHJ, Davis MJ, Johnson LA, Raber J. Early effects of whole-body (56)Fe irradiation on hippocampal function in C57BL/6J mice. Radiat Res 2013; 179:590-6. [PMID: 23510274 DOI: 10.1667/rr2946.1] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Relatively little is known about early irradiation effects on hippocampal function in wild-type mice. In this study, the effects of (56)Fe irradiation on hippocampal function were assessed starting 2 weeks after whole-body irradiation. Compared to sham irradiation, radiation impaired novel object recognition in female and male C57BL/6J wild-type mice. There were no effects of irradiation on contextual fear conditioning or spatial memory retention in the water maze. It is possible that oxidative damage might contribute to radiation-induced cognitive changes. Therefore, hippocampal and cortical levels of 3-nitrotyrosine (3NT) and lipid peroxidation, measures of oxidative damage were assessed. There were no effects of irradiation on these measures of oxidative damage. As (56)Fe irradiation can increase reactive oxygen species (ROS) levels, which may contribute to the impairments in novel object recognition, the effects of the antioxidant alpha-lipoic acid (ALA) on cognition following sham irradiation and irradiation were also assessed. ALA did not prevent radiation-induced impairments in novel object recognition and impaired spatial memory retention of sham-irradiated and irradiated mice in the probe trial after the first day of hidden platform training in the water maze. Thus, the novel object recognition test is particularly sensitive to detect early cognitive effects of (56)Fe irradiation through a mechanism unlikely involving ROS or oxidative damage.
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Affiliation(s)
- Gwendolen E Haley
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, Oregon 97239, USA
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Haley GE, Eghlidi DH, Kohama SG, Urbanski HF, Raber J. Association of microtubule associated protein-2, synaptophysin, and apolipoprotein E mRNA and protein levels with cognition and anxiety levels in aged female rhesus macaques. Behav Brain Res 2012; 232:1-6. [PMID: 22475553 DOI: 10.1016/j.bbr.2012.03.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 03/16/2012] [Accepted: 03/20/2012] [Indexed: 02/06/2023]
Abstract
The dendritic protein microtubule associated protein 2 (MAP-2), the presynaptic marker synaptophysin (SYN), and apolipoprotein E (APOE), a protein which plays a role in lipid transport and metabolism and affects synaptic activity show changes with age. We analyzed post-mortem tissue from aged female rhesus macaques cognitively tested in a spatial maze and classified as good spatial performers (GSP) or poor spatial performers (PSP) and behaviorally tested in a playroom and classified as bold or reserved animals. MAP2, SYN, and APOE mRNA and protein levels in the prefrontal cortex (PFC), hippocampus, and amygdala, were assessed using qRT-PCR and western blot. In the amygdala, bold monkeys had higher levels of MAP2 and SYN mRNA than reserved monkeys. MAP2 mRNA correlated positively with amygdala size on the right, left, and combined left and right sides, while SYN mRNA levels correlated positively with the size of the right amygdala. In the hippocampus, SYN and APOE protein levels were higher in GSP than PSP animals. Thus, in aged nonhuman primates, classification of measures of anxiety is associated with differences in selected mRNA, but not protein, levels. In contrast, classification of cognitive performance is associated with differences in selected protein, but not mRNA, levels.
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Affiliation(s)
- Gwendolen E Haley
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR 97239, USA
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Measures of anxiety, amygdala volumes, and hippocampal scopolamine phMRI response in elderly female rhesus macaques. Neuropharmacology 2011; 62:385-90. [PMID: 21867720 DOI: 10.1016/j.neuropharm.2011.08.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 08/10/2011] [Accepted: 08/10/2011] [Indexed: 12/28/2022]
Abstract
In nonhuman primates, anxiety levels are typically assessed by observing social hierarchies or behavior in an intruder task. As measures of anxiety might influence performance on a particular cognitive task, it is important to analyze these measures in the same room as used for the cognitive task. As we use a playroom for the spatial maze test, we classified elderly female rhesus macaques (Macaca mulatta) monkeys, as bold or reserved monkeys based on the time spent in specific areas of this room. Based on their exploratory behavior in the playroom, bold monkeys were defined as animals that spent 20% more time in the unprotected areas of the room than in the protected areas, whereas reserved monkeys spent a comparable amount of time in both areas. MRI analyses showed that reserved monkeys had a smaller amygdala compared to bold monkeys but there were no group differences in hippocampal volumes. In addition, the amount of time spent in the corners of the room was negatively correlated with the right amygdala as well as the total amygdala size. Finally, reserved monkeys showed a lower phMRI response to the muscarinic receptor antagonist scopolamine compared to the bold monkeys. Thus, in elderly female nonhuman primates measures of anxiety are associated with structural amygdala differences and hippocampal muscarinic receptor function. This article is part of a Special Issue entitled 'Anxiety and Depression'.
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Haley GE, Urbanski HF, Kohama SG, Messaoudi I, Raber J. Spatial Memory Performance Associated with Measures of Immune Function in Elderly Female Rhesus Macaques. Eur Geriatr Med 2011; 2:117-121. [PMID: 21603071 PMCID: PMC3097089 DOI: 10.1016/j.eurger.2011.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We recently reported that in aged female rhesus macaques, spatial learning and memory correlates with circadian sleep-wake measures and hippocampal muscarinic type 1 (M(1)) receptor binding. To investigate if spatial memory also correlates with measures of immune function, we now assessed the magnitude of the adaptive immune response to vaccination in the same old female rhesus macaques. Cognitively characterized animals were classified as good spatial performers (GSP) or poor spatial performers (PSP) based on performance in the Spatial Foodport maze. The GSP group had higher frequency of CD8, but not CD4, interferon-γ (IFN-γ) producing cells following vaccination compared to the PSP group, suggesting a stronger CD8 T cell response in the GSP group. In addition, the number of CD-8 IFN-γ positive cells correlated with measures of sleep quality. Interestingly, the PSP group had a significantly higher antibody titer compared to the GSP group, and antibody titer negatively correlated with day-time activity. Thus, in aged female rhesus macaques, superior cognitive performance is correlated with a more robust CD8 T cell response but a reduced antibody response to vaccination.
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Affiliation(s)
- Gwendolen E. Haley
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR 97239
- Division of Neuroscience Oregon National Primate Research Center, Beaverton, OR 97006
| | - Henryk F. Urbanski
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR 97239
- Division of Neuroscience Oregon National Primate Research Center, Beaverton, OR 97006
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97239
| | - Steven G. Kohama
- Division of Neuroscience Oregon National Primate Research Center, Beaverton, OR 97006
| | - Ilhem Messaoudi
- Division of Neuroscience Oregon National Primate Research Center, Beaverton, OR 97006
- Division of Pathobiology and Immunology, Oregon National Primate Research Center Vaccine and Gene Therapy Institute, Beaverton, OR 97006
| | - Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR 97239
- Division of Neuroscience Oregon National Primate Research Center, Beaverton, OR 97006
- Department of Neurology, Oregon Health and Science University, Portland OR 97239
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