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Mehak SF, Shivakumar AB, Saraf V, Johansson M, Gangadharan G. Apathy in Alzheimer's disease: A neurocircuitry based perspective. Ageing Res Rev 2023; 87:101891. [PMID: 36871779 DOI: 10.1016/j.arr.2023.101891] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/25/2023] [Accepted: 02/21/2023] [Indexed: 03/07/2023]
Abstract
In addition to memory deficits and other cognitive disturbances, patients with Alzheimer's disease (AD) experience neuropsychiatric symptoms, notably apathy, which is a state of impaired motivation observed by deficits in goal directed behavior. Apathy is a multifaceted neuropsychiatric condition and appears to be a prognostic indicator, correlating with the progression of AD. Strikingly, recent studies point out that the neurodegenerative pathology of AD may drive apathy independent of cognitive decline. These studies also highlight that neuropsychiatric symptoms, in particular apathy, might manifest early in AD. Here, we review the current understanding of the neurobiological underpinnings of apathy as a neuropsychiatric symptom of AD. Specifically, we highlight the neural circuits and brain regions recognized to be correlated with the apathetic symptomatology. We also discuss the current evidence that supports the notion that apathy and cognitive deficits may develop as independent but concurrent phenomena driven by AD pathology, suggesting its efficacy as an additional outcome measure in Alzheimer's disease clinical trials. The current and prospective therapeutic interventions for apathy in AD from a neurocircuitry based perspective are also reviewed.
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Affiliation(s)
- Sonam Fathima Mehak
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India.
| | - Apoorva Bettagere Shivakumar
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India.
| | - Vikyath Saraf
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India.
| | - Maurits Johansson
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, SUS, Sweden; Division of Clinical Sciences, Helsingborg, Department of Clinical Sciences Lund, Lund University, Sweden; Department of Psychiatry, Helsingborg Hospital, Sweden.
| | - Gireesh Gangadharan
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India.
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Fitzgerald S, Gracey F, Trigg E, Broomfield N. Predictors and correlates of emotionalism across acquired and progressive neurological conditions: A systematic review. Neuropsychol Rehabil 2022; 33:945-987. [PMID: 35323084 DOI: 10.1080/09602011.2022.2052326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Emotionalism can develop following a range of neurological disorders; however the aetiology of emotionalism is still unclear. To identify anatomical, neuropsychological and psychological predictors and correlates of emotionalism across neurological disorders: stroke, Parkinson's disease, multiple sclerosis, traumatic brain injury, Alzheimer's disease, vascular dementia and amyotrophic lateral sclerosis. To explore if these predictors and correlates of emotionalism differ across neurological disorders. A comprehensive systematic search was completed of four databases: MEDLINE, CINAHL Complete, PsycINFO and EMBASE. Methodological quality was assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies and each study was graded according to the level of evidence using the Scottish Intercollegiate Guidelines Network. Fifty papers (participants N = 1922) were included. 25 studies were rated as "Fair," 21 "Good" and 4 "Poor." The review identified predictors and correlates found in several neurological disorder such as bulbar networks, serotonergic pathways, genetics and female gender. Multiple studies across diseases (stroke, MS, ALS) indicate emotionalism is associated with cognitive impairment, especially frontal deficits. Due to the disproportionate number of studies identified across neurological disorders, it is difficult to draw definitive answers. Further research is required across neurological disorders to explore similarities and differences in anatomical, neuropsychological and psychological predictors and correlates.
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Affiliation(s)
- Sophie Fitzgerald
- Department of Clinical Psychology and Psychological Therapies, Norwich Medical School, University of East Anglia, Norwich, UK
| | - Fergus Gracey
- Department of Clinical Psychology and Psychological Therapies, Norwich Medical School, University of East Anglia, Norwich, UK
| | - Emma Trigg
- Department of Clinical Psychology and Psychological Therapies, Norwich Medical School, University of East Anglia, Norwich, UK
| | - Niall Broomfield
- Department of Clinical Psychology and Psychological Therapies, Norwich Medical School, University of East Anglia, Norwich, UK
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Valotassiou V, Sifakis N, Tzavara C, Lykou E, Tsinia N, Kamtsadeli V, Sali D, Angelidis G, Psimadas D, Tsougos I, Papageorgiou SG, Georgoulias P, Papatriantafyllou J. Differences of apathy perfusion correlates between Alzheimer's disease and frontotemporal dementia. A 99mTc-HMPAO SPECT study with automated Brodmann areas analysis. Int J Psychiatry Clin Pract 2022; 26:14-22. [PMID: 33207961 DOI: 10.1080/13651501.2020.1846752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVES To explore differences of apathy perfusion correlates between Alzheimer's disease (AD) and Frontotemporal dementia (FTD) using perfusion SPECT. METHODS We studied 75 FTD and 66 AD patients. We evaluated apathy using Neuropsychiatric Inventory (NPI). We compared perfusion of BAs on left (L) and right (R) hemisphere in AD and FTD. RESULTS Apathy in AD was significantly and negatively correlated with dorsolateral prefrontal cortex bilaterally, right anterior prefrontal cortex, inferior frontal cortex bilaterally, especially on the right, orbital part of inferior frontal gyrus bilaterally, left dorsal anterior cingulate cortex, right primary and secondary visual cortex, and with bilateral anterior and dorsolateral prefrontal cortex, inferior frontal cortex and orbital part of inferior frontal gyrus, bilaterally, bilateral anterior -ventral and dorsal- cingulate cortex, left posterior ventral cingulate cortex, right inferior, middle and anterior temporal gyri, entorhinal and parahippocampal cortex in FTD. CONCLUSIONS Significant overlapping of apathy perfusion correlates between AD and FTD is seen in frontal areas and anterior cingulate. Right occipital cortex is also involved in AD, while right temporal cortex and left posterior cingulate are involved in FTD. Nuclear imaging could be a useful biomarker for revealing apathy underlying mechanisms, resulting in directed treatments.KEYPOINTSUnderlying neural networks and clinical manifestation of apathy may differ between AD and FTD.Apathy in AD is correlated with hypoperfusion in bilateral frontal areas, more prominent on the right, left anterior cingulate and right occipital cortex.Apathy in FTD is correlated with hypoperfusion in bilateral frontal areas, bilateral anterior cingulate, left posterior cingulate and right temporal cortex.Brain perfusion SPECT with automated BAs analysis and comparison with normal healthy subjects may provide significant information for apathy mechanisms in neurodegenerative disorders, affecting patients' treatment.
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Affiliation(s)
- Varvara Valotassiou
- Nuclear Medicine Department, University Hospital of Larissa, Thessaly, Greece
| | - Nikolaos Sifakis
- Nuclear Medicine Department, "Alexandra" General Hospital, Athens, Greece
| | - Chara Tzavara
- Nuclear Medicine Department, University Hospital of Larissa, Thessaly, Greece
| | - Evi Lykou
- 3rd Age Day Care Center, IASIS, Athens, Greece
| | - Niki Tsinia
- 1st University Psychiatric Department, Aeginition Hospital, Athens, Greece
| | | | - Dimitra Sali
- Neurology Department, Evrokliniki, Athens, Greece
| | - George Angelidis
- Nuclear Medicine Department, University Hospital of Larissa, Thessaly, Greece
| | - Dimitrios Psimadas
- Nuclear Medicine Department, University Hospital of Larissa, Thessaly, Greece
| | - Ioannis Tsougos
- Medical Physics Department, Medical School, University of Thessaly, Thessaly, Greece
| | | | | | - John Papatriantafyllou
- 3rd Age Day Care Center, IASIS, Athens, Greece.,Memory Disorders Clinic, Medical Center, Athens, Greece
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Reddy Mukku S, Desai G, Chaturvedi S. Depression and somatic symptoms in dementia: A narrative review. JOURNAL OF GERIATRIC MENTAL HEALTH 2020. [DOI: 10.4103/jgmh.jgmh_4_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Singh K, Jayaram M, Kaare M, Leidmaa E, Jagomäe T, Heinla I, Hickey MA, Kaasik A, Schäfer MK, Innos J, Lilleväli K, Philips MA, Vasar E. Neural cell adhesion molecule Negr1 deficiency in mouse results in structural brain endophenotypes and behavioral deviations related to psychiatric disorders. Sci Rep 2019; 9:5457. [PMID: 30932003 PMCID: PMC6443666 DOI: 10.1038/s41598-019-41991-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 03/21/2019] [Indexed: 12/24/2022] Open
Abstract
Neuronal growth regulator 1 (NEGR1) belongs to the immunoglobulin (IgLON) superfamily of cell adhesion molecules involved in cortical layering. Recent functional and genomic studies implicate the role of NEGR1 in a wide spectrum of psychiatric disorders, such as major depression, schizophrenia and autism. Here, we investigated the impact of Negr1 deficiency on brain morphology, neuronal properties and social behavior of mice. In situ hybridization shows Negr1 expression in the brain nuclei which are central modulators of cortical-subcortical connectivity such as the island of Calleja and the reticular nucleus of thalamus. Brain morphological analysis revealed neuroanatomical abnormalities in Negr1−/− mice, including enlargement of ventricles and decrease in the volume of the whole brain, corpus callosum, globus pallidus and hippocampus. Furthermore, decreased number of parvalbumin-positive inhibitory interneurons was evident in Negr1−/− hippocampi. Behaviorally, Negr1−/− mice displayed hyperactivity in social interactions and impairments in social hierarchy. Finally, Negr1 deficiency resulted in disrupted neurite sprouting during neuritogenesis. Our results provide evidence that NEGR1 is required for balancing the ratio of excitatory/inhibitory neurons and proper formation of brain structures, which is prerequisite for adaptive behavioral profiles. Therefore, Negr1−/− mice have a high potential to provide new insights into the neural mechanisms of neuropsychiatric disorders.
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Affiliation(s)
- Katyayani Singh
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia. .,Centre of Excellence in Genomics and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.
| | - Mohan Jayaram
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.,Centre of Excellence in Genomics and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Maria Kaare
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.,Centre of Excellence in Genomics and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Este Leidmaa
- Institute of Molecular Psychiatry, University of Bonn, Sigmund-Freud-Str.25, 53127, Bonn, Germany
| | - Toomas Jagomäe
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.,Centre of Excellence in Genomics and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Indrek Heinla
- Department of Psychology, UiT The Arctic University of Norway, Postboks 6050 Langnes, 9037, Tromso, Norway
| | - Miriam A Hickey
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Allen Kaasik
- Department of Pharmacology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Michael K Schäfer
- Department for Anesthesiology, University Medical Center and Focus Program Translational Neuroscience (FTN), Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Jürgen Innos
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.,Centre of Excellence in Genomics and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Kersti Lilleväli
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.,Centre of Excellence in Genomics and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Mari-Anne Philips
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.,Centre of Excellence in Genomics and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
| | - Eero Vasar
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia.,Centre of Excellence in Genomics and Translational Medicine, University of Tartu, 19 Ravila Street, 50411, Tartu, Estonia
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Brain Perfusion Correlates of Apathy in Alzheimer's Disease. Dement Neurocogn Disord 2018; 17:50-56. [PMID: 30906392 PMCID: PMC6427971 DOI: 10.12779/dnd.2018.17.2.50] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 06/29/2018] [Indexed: 11/27/2022] Open
Abstract
Background and Purpose Apathy is one of the most common neuropsychiatric symptoms in patients with Alzheimer's disease (AD). It may have adverse impacts on the progression of AD. However, its neurobiological underpinnings remain unclear. The objective of this study was to investigate differences in regional cerebral blood flow (rCBF) between AD patients with apathy and those without apathy. Methods Sixty-six apathetic AD patients and 66 AD patients without apathy completed Neuropsychiatric Inventory (NPI) and underwent technetium-99m hexamethylpropylene amine oxime single-photon emission computed tomography (SPECT) scans. Voxel-wise differences in rCBF between the 2 groups were examined. Association between rCBF and levels of apathy in the apathetic group was also assessed. Results AD patients with apathy showed lower rCBF in the bilateral orbitofrontal cortex, left putamen, left nucleus accumbens, left thalamus, and bilateral insula than those without (all p<0.005). Mean perfusion across all significant clusters showed a negative linear correlation with NPI apathy score in AD patients with apathy (β=-0.25; p=0.04). Conclusions Hypoperfusion in the prefrontal, striatal, and insular areas may be neural correlates of apathy in AD patients.
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Transgenic autoinhibition of p21-activated kinase exacerbates synaptic impairments and fronto-dependent behavioral deficits in an animal model of Alzheimer's disease. Aging (Albany NY) 2018; 9:1386-1403. [PMID: 28522792 PMCID: PMC5472739 DOI: 10.18632/aging.101239] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 05/11/2017] [Indexed: 11/28/2022]
Abstract
Defects in p21-activated kinase (PAK) lead to dendritic spine abnormalities and are sufficient to cause cognition impairment. The decrease in PAK in the brain of Alzheimer's disease (AD) patients is suspected to underlie synaptic and dendritic disturbances associated with its clinical expression, particularly with symptoms related to frontal cortex dysfunction. To investigate the role of PAK combined with Aβ and tau pathologies (3xTg-AD mice) in the frontal cortex, we generated a transgenic model of AD with a deficit in PAK activity (3xTg-AD-dnPAK mice). PAK inactivation had no effect on Aβ40 and Aβ42 levels, but increased the phosphorylation ratio of tau in detergent-insoluble protein fractions in the frontal cortex of 18-month-old heterozygous 3xTg-AD mice. Morphometric analyses of layer II/III pyramidal neurons in the frontal cortex showed that 3xTg-AD-dnPAK neurons exhibited significant dendritic attrition, lower spine density and longer spines compared to NonTg and 3xTg-AD mice. Finally, behavioral assessments revealed that 3xTg-AD-dnPAK mice exhibited pronounced anxious traits and disturbances in social behaviors, reminiscent of fronto-dependent symptoms observed in AD. Our results substantiate a critical role for PAK in the genesis of neuronal abnormalities in the frontal cortex underlying the emergence of psychiatric-like symptoms in AD.
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Van Dam D, Vermeiren Y, Dekker AD, Naudé PJW, Deyn PPD. Neuropsychiatric Disturbances in Alzheimer's Disease: What Have We Learned from Neuropathological Studies? Curr Alzheimer Res 2017; 13:1145-64. [PMID: 27137218 PMCID: PMC5070416 DOI: 10.2174/1567205013666160502123607] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 03/04/2016] [Accepted: 04/27/2016] [Indexed: 12/16/2022]
Abstract
Neuropsychiatric symptoms (NPS) are an integral part of the dementia syndrome and were therefore recently included in the core diagnostic criteria of dementia. The near universal prevalence of NPS in Alzheimer's disease (AD), combined with their disabling effects on patients and caregivers, is contrasted by the fact that few effective and safe treatments exist, which is in part to be attributed to our incomplete understanding of the neurobiology of NPS. In this review, we describe the pathological alterations typical for AD, including spreading and evolution of burden, effect on the molecular and cellular integrity, functional consequences and atrophy of NPS-relevant brain regions and circuits in correlation with specific NPS assessments. It is thereby clearly established that NPS are fundamental expressions of the underlying neurodegenerative brain disease and not simply reflect the patients' secondary response to their illness. Neuropathological studies, moreover, include a majority of end-stage patient samples, which may not correctly represent the pathophysiological environment responsible for particular NPS that may already be present in an early stage, or even prior to AD diagnosis. The burdensome nature and high prevalence of NPS, in combination with the absence of effective and safe pharmacotherapies, provide a strong incentive to continue neuropathological and neurochemical, as well as imaging and other relevant approaches to further improve our apprehension of the neurobiology of NPS.
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Affiliation(s)
| | | | | | | | - Peter P De Deyn
- Laboratory of Neurochemistry and Behaviour, Institute Born-Bunge, Department of Biomedical Sciences, Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, and, Faculty of Medical and Health Care Sciences, University of Antwerp, Universiteitsplein 1, BE-2610 Wilrijk (Antwerp), Belgium
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9
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Prefrontal Activity and Connectivity with the Basal Ganglia during Performance of Complex Cognitive Tasks Is Associated with Apathy in Healthy Subjects. PLoS One 2016; 11:e0165301. [PMID: 27798669 PMCID: PMC5087839 DOI: 10.1371/journal.pone.0165301] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 10/10/2016] [Indexed: 11/19/2022] Open
Abstract
Objective Convergent evidence indicates that apathy affects cognitive behavior in different neurological and psychiatric conditions. Studies of clinical populations have also suggested the primary involvement of the prefrontal cortex and the basal ganglia in apathy. These brain regions are interconnected at both the structural and functional levels and are deeply involved in cognitive processes, such as working memory and attention. However, it is unclear how apathy modulates brain processing during cognition and whether such a modulation occurs in healthy young subjects. To address this issue, we investigated the link between apathy and prefrontal and basal ganglia function in healthy young individuals. We hypothesized that apathy may be related to sub-optimal activity and connectivity in these brain regions. Methods Three hundred eleven healthy subjects completed an apathy assessment using the Starkstein’s Apathy Scale and underwent fMRI during working memory and attentional performance tasks. Using an ROI approach, we investigated the association of apathy with activity and connectivity in the DLPFC and the basal ganglia. Results Apathy scores correlated positively with prefrontal activity and negatively with prefrontal-basal ganglia connectivity during both working memory and attention tasks. Furthermore, prefrontal activity was inversely related to attentional behavior. Conclusions These results suggest that in healthy young subjects, apathy is a trait associated with inefficient cognitive-related prefrontal activity, i.e., it increases the need for prefrontal resources to process cognitive stimuli. Furthermore, apathy may alter the functional relationship between the prefrontal cortex and the basal ganglia during cognition.
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Bensamoun D, Guignard R, Furst AJ, Derreumaux A, Manera V, Darcourt J, Benoit M, Robert PH, David R. Associations between Neuropsychiatric Symptoms and Cerebral Amyloid Deposition in Cognitively Impaired Elderly People. J Alzheimers Dis 2016; 49:387-98. [PMID: 26484900 DOI: 10.3233/jad-150181] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND Neuropsychiatric symptoms, also known as behavioral and psychological symptoms of dementia (BPSD), affect the majority of patients with dementia, and result in a greater cognitive and functional impairment. OBJECTIVE To investigate associations between BPSD and amyloid cerebral deposition as measured by 18F-Florbetapir-PET quantitative uptake in elderly subjects with and without cognitive impairment. METHODS Participants with cognitive impairment [mild cognitive impairment (MCI) or Alzheimer's disease (AD)] and healthy controls (HC) from the ADNI cohort (Alzheimer Disease Neuroimaging Initiative) who underwent an 18F-florbetapir PET scan between May 2010 and March 2014 were included. Clinical assessments included the Clinical Dementia Rating, the Mini-Mental State Examination (MMSE), and the Neuropsychiatric Inventory. Freesurfer software was used to extract PET counts based on T1-based structural ROI (frontal, cingulate, parietal, and temporal). Spearman's partial correlation scores between BPSD severity and regional amyloid uptake were calculated. RESULTS Data for 657 participants [age = 72.6 (7.19); MMSE = 27.4 (2.67)] were analyzed, including 230 HC [age = 73.1 (6.02); MMSE = 29 (1.21)], 308 MCI [age = 71.5 (7.44); MMSE = 28.0 (1.75)], and 119 AD subjects [age = 74.7 (8.05); MMSE = 23.1 (2.08)]. Considering all diagnostic groups together, positive significant correlations were found between anxiety and 18F-florbetapir uptake in the frontal (r = 0.102; p = 0.009), cingulate (r = 0.083; p = 0.034), and global cerebral uptake (r = 0.099; p = 0.011); between irritability and frontal (r = 0.089; p = 0.023), cingulate (r = 0.085; p = 0.030), parietal (r = 0.087; p = 0.025), and global cerebral uptake (r = 0.093; p = 0.017); in the MCI subgroup, between anxiety and frontal (r = 0.126; p = 0.03) and global uptake (r = 0.14; p = 0.013); in the AD subgroup, between irritability and parietal uptake (r = 0.201; p = 0.03). CONCLUSION Anxiety and irritability are associated with greater amyloid deposition in the neurodegenerative process leading to AD.
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Affiliation(s)
- David Bensamoun
- Centre Memoire de Ressources et de Recherche, Institut Claude Pompidou, EA CoBTek, University of Nice Sophia Antipolis, Nice, France
| | - Renaud Guignard
- Department of Nuclear Medicine, Hôpital de La Tour, Meyrin, GE, Switzerland
| | - Ansgar J Furst
- Department of Psychiatry and Behavioral Sciences, Department of Neurology and Neurological Sciences, Stanford University, Stanford, USA; War Related Illness and Injury Study Center, VA Palo Alto, Palo Alto, USA
| | - Alexandre Derreumaux
- Centre Memoire de Ressources et de Recherche, Institut Claude Pompidou, EA CoBTek, University of Nice Sophia Antipolis, Nice, France
| | - Valeria Manera
- Centre Memoire de Ressources et de Recherche, Institut Claude Pompidou, EA CoBTek, University of Nice Sophia Antipolis, Nice, France
| | - Jacques Darcourt
- Nuclear Medicine Department, Antoine Lacassagne Center, Nice, France
| | - Michel Benoit
- Department of Psychiatry, University Hospital of Nice, France
| | - Philippe H Robert
- Centre Memoire de Ressources et de Recherche, Institut Claude Pompidou, EA CoBTek, University of Nice Sophia Antipolis, Nice, France
| | - Renaud David
- Centre Memoire de Ressources et de Recherche, Institut Claude Pompidou, EA CoBTek, University of Nice Sophia Antipolis, Nice, France
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Pasqualetti G, Tognini S, Calsolaro V, Polini A, Monzani F. Potential drug-drug interactions in Alzheimer patients with behavioral symptoms. Clin Interv Aging 2015; 10:1457-66. [PMID: 26392756 PMCID: PMC4573195 DOI: 10.2147/cia.s87466] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The use of multi drug regimens among the elderly population has increased tremendously over the last decade although the benefits of medications are always accompanied by potential harm, even when prescribed at recommended doses. The elderly populations are particularly at an increased risk of adverse drug reactions considering comorbidity, poly-therapy, physiological changes affecting the pharmacokinetics and pharmacodynamics of many drugs and, in some cases, poor compliance due to cognitive impairment and/or depression. In this setting, drug–drug interaction may represent a serious and even life-threatening clinical condition. Moreover, the inability to distinguish drug-induced symptoms from a definitive medical diagnosis often results in addition of yet another drug to treat the symptoms, which in turn increases drug–drug interactions. Cognitive enhancers, including acetylcholinesterase inhibitors and memantine, are the most widely prescribed agents for Alzheimer’s disease (AD) patients. Behavioral and psychological symptoms of dementia, including psychotic symptoms and behavioral disorders, represent noncognitive disturbances frequently observed in AD patients. Antipsychotic drugs are at high risk of adverse events, even at modest doses, and may interfere with the progression of cognitive impairment and interact with several drugs including anti-arrhythmics and acetylcholinesterase inhibitors. Other medications often used in AD patients are represented by anxiolytic, like benzodiazepine, or antidepressant agents. These agents also might interfere with other concomitant drugs through both pharmacokinetic and pharmacodynamic mechanisms. In this review we focus on the most frequent drug–drug interactions, potentially harmful, in AD patients with behavioral symptoms considering both physiological and pathological changes in AD patients, and potential pharmacodynamic/pharmacokinetic drug interaction mechanisms.
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Affiliation(s)
- Giuseppe Pasqualetti
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Sara Tognini
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Valeria Calsolaro
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Antonio Polini
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Fabio Monzani
- Geriatrics Unit, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
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Hirao K, Pontone GM, Smith GS. Molecular imaging of neuropsychiatric symptoms in Alzheimer's and Parkinson's disease. Neurosci Biobehav Rev 2015; 49:157-70. [PMID: 25446948 PMCID: PMC4806385 DOI: 10.1016/j.neubiorev.2014.11.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 10/27/2014] [Accepted: 11/12/2014] [Indexed: 01/14/2023]
Abstract
Neuropsychiatric symptoms (NPS) are very common in neurodegenerative diseases and are a major contributor to disability and caregiver burden. There is accumulating evidence that NPS may be a prodrome and/or a "risk factor" of neurodegenerative diseases. The medications used to treat these symptoms in younger patients are not very effective in patients with neurodegenerative disease and may have serious side effects. An understanding of the neurobiology of NPS is critical for the development of more effective intervention strategies. Targeting these symptoms may also have implications for prevention of cognitive or motor decline. Molecular brain imaging represents a bridge between basic and clinical observations and provides many opportunities for translation from animal models and human post-mortem studies to in vivo human studies. Molecular brain imaging studies in Alzheimer's disease (AD) and Parkinson's disease (PD) are reviewed with a primary focus on positron emission tomography studies of NPS. Future directions for the field of molecular imaging in AD and PD to understand the neurobiology of NPS will be discussed.
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Affiliation(s)
- Kentaro Hirao
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, USA; Department of Geriatric Medicine, Tokyo Medical University, Tokyo, Japan
| | - Gregory M Pontone
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, USA
| | - Gwenn S Smith
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, USA.
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Hancock SM, Finkelstein DI, Adlard PA. Glia and zinc in ageing and Alzheimer's disease: a mechanism for cognitive decline? Front Aging Neurosci 2014; 6:137. [PMID: 25009495 PMCID: PMC4069481 DOI: 10.3389/fnagi.2014.00137] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 06/09/2014] [Indexed: 11/13/2022] Open
Abstract
Normal ageing is characterized by cognitive decline across a range of neurological functions, which are further impaired in Alzheimer’s disease (AD). Recently, alterations in zinc (Zn) concentrations, particularly at the synapse, have emerged as a potential mechanism underlying the cognitive changes that occur in both ageing and AD. Zn is now accepted as a potent neuromodulator, affecting a variety of signaling pathways at the synapse that are critical to normal cognition. While the focus has principally been on the neuron: Zn interaction, there is a growing literature suggesting that glia may also play a modulatory role in maintaining both Zn ion homeostasis and the normal function of the synapse. Indeed, zinc transporters (ZnT’s) have been demonstrated in glial cells where Zn has also been shown to have a role in signaling. Furthermore, there is increasing evidence that the pathogenesis of AD critically involves glial cells (such as astrocytes), which have been reported to contribute to amyloid-beta (Aβ) neurotoxicity. This review discusses the current evidence supporting a complex interplay of glia, Zn dyshomeostasis and synaptic function in ageing and AD.
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Affiliation(s)
- Sara M Hancock
- Synaptic Neurobiology Laboratory, Florey Institute of Neuroscience and Mental Health Parkville, VIC, Australia
| | - David I Finkelstein
- Parkinson's Disease Laboratory, Florey Institute of Neuroscience and Mental Health Parkville, VIC, Australia
| | - Paul A Adlard
- Synaptic Neurobiology Laboratory, Florey Institute of Neuroscience and Mental Health Parkville, VIC, Australia
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15
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Abstract
BACKGROUND Apathy is one of the most frequent "behavioral and psychological signs and symptoms of dementia" (BPSD) encountered in Alzheimer's disease (AD). There is a growing interest in the early diagnosis of apathetic elderly patients in the community since apathy has been associated with reduced daily functioning, caregiver distress, and poor outcome. The generalization of neuroimaging techniques might be able to offer help in this domain. METHODS Within this context we conducted an extensive electronic search from the databases included in the National Library of Medicine as well as PsychInfo and Google Scholar for neuroimaging findings of apathy in AD. RESULTS Neuroimaging findings lend support to the notion that frontal-subcortical networks are involved in the occurrence of apathy in AD. CONCLUSIONS Longitudinal studies comparing patients and normal individuals might allow us to infer on the association between apathy and neurodegenerative diseases and what can brain imaging markers tell us about the characterization of this association, thus revealing disease patterns, helping to distinguish clinically distinct cognitive syndromes, and allowing predictions.
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Tascone LDS, Bottino CMDC. Neurobiology of neuropsychiatric symptoms in Alzheimer's disease: A critical review with a focus on neuroimaging. Dement Neuropsychol 2013; 7:236-243. [PMID: 29213845 PMCID: PMC5619193 DOI: 10.1590/s1980-57642013dn70300002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The objective of this critical review of the literature was to reveal the neural
circuits involved in the occurrence of neuropsychiatric symptoms (NPS) in
Alzheimer's disease (AD) patients through the association of these symptoms with
neuroimaging findings. The search for articles was performed on PUBMED from
January 2000 to May 2013, using the key words: Dementia AND BPSD; Dementia AND
Neuropsychiatric Symptoms; and Dementia AND Psychosis, Delusions,
Hallucinations, Agitation, Depression, Anxiety, Apathy, Euphoria, Disinhibition,
Irritability, Aberrant Motor Behavior, Sleep or Eating Disorders. Forty-six
articles were reviewed and important contributions, especially regarding the
psychopathological concepts discussed, were also considered even if not included
in this time period. The available evidence suggests the three most relevant
neurobiological models for neuropsychiatric symptoms in Alzheimer's disease are
the frontal-subcortical circuits, the cortico-cortical networks, and the
monoaminergic system. We discussed the association of the individual symptoms or
syndromes with these models.
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Waldemar G, Gauthier S, Jones R, Wilkinson D, Cummings J, Lopez O, Zhang R, Xu Y, Sun Y, Knox S, Richardson S, Mackell J. Effect of donepezil on emergence of apathy in mild to moderate Alzheimer's disease. Int J Geriatr Psychiatry 2011; 26:150-7. [PMID: 20597141 DOI: 10.1002/gps.2507] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To determine whether donepezil treatment (10 mg/day over 24 weeks) is associated with delayed emergence of apathy in patients with mild to moderate Alzheimer's disease (AD) and to explore relationships between donepezil's effects on apathy and other Neuropsychiatric Inventory (NPI)-measured behavioural symptoms. METHODS Two randomised, double-blind, parallel-group, placebo-controlled studies that met prespecified criteria and were sufficiently similar to allow data pooling were derived from all donepezil AD clinical trials. Patients scoring from 10 to 26 on baseline Mini-Mental Status Examination were included. A clinical milestone for apathy and other NPI items was defined as the first emergence of a composite score (frequency × severity) ≥ 3. Differences in time to event (i.e. milestone) between donepezil- and placebo-treated groups were assessed using the Kaplan-Meier method and log-rank test. Shift tables were constructed to evaluate clinical milestone status for apathy and other NPI items at baseline and endpoint, and were analysed using the Cochran-Mantel-Haenszel (CMH) test, stratified by baseline status. RESULTS Of all NPI items, apathy had the highest proportion of subjects scoring ≥ 3 at baseline. Donepezil was superior to placebo on both apathy milestone analyses (time-to-event log-rank test and shift table CMH test, p = 0.01). Aberrant motor behaviour demonstrated similar benefit. CONCLUSIONS Donepezil treatment appears to have resulted in a significant reduction over 6 months of the emergence of apathy in patients with AD. These data suggest that a prospective clinical trial in patients with early AD that includes apathy as a primary outcome measure may be warranted.
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Affiliation(s)
- Gunhild Waldemar
- Memory Disorders Research Group, Department of Neurology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
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18
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Mitchell RA, Herrmann N, Lanctôt KL. The role of dopamine in symptoms and treatment of apathy in Alzheimer's disease. CNS Neurosci Ther 2010; 17:411-27. [PMID: 20560994 DOI: 10.1111/j.1755-5949.2010.00161.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is characterized by a number of serious and debilitating behavioral and psychological symptoms of dementia (BPSD). The most common of these BPSD is apathy, which represents a major source of morbidity and premature institutionalization in the AD population. Many studies have identified discrete changes to the dopaminergic (DAergic) system in patients with AD. The DAergic system is closely related to the brain reward system (BRS) and some studies have suggested that dysfunction in the DAergic system may account for symptoms of apathy in the AD population. METHOD Changes to the dopamine (DA) system in AD will be reviewed, and evidence supporting the involvement of the DAergic system in the development of apathy will be examined. Additionally, some pharmacological interventions with DA activity have been identified. The utility of these treatments in the AD population will be reviewed, with a focus on apathy as an outcome. RESULTS Evidence presented in this review suggests that DA dysfunction in discrete brain areas is an important correlate of apathy in AD and that the DAergic system may be a rational target for pharmacological treatment of apathy.
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Affiliation(s)
- Robert A Mitchell
- Neuropsychopharmacology, Sunnybrook Health Sciences Centre, Toronto, Canada
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19
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Tagariello P, Girardi P, Amore M. Depression and apathy in dementia: Same syndrome or different constructs? A critical review. Arch Gerontol Geriatr 2009; 49:246-249. [DOI: 10.1016/j.archger.2008.09.002] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 09/06/2008] [Accepted: 09/08/2008] [Indexed: 11/26/2022]
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Smith GS, Kramer E, Ma Y, Hermann CR, Dhawan V, Chaly T, Eidelberg D. Cholinergic modulation of the cerebral metabolic response to citalopram in Alzheimer's disease. Brain 2009; 132:392-401. [PMID: 19153152 PMCID: PMC2640217 DOI: 10.1093/brain/awn326] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 10/23/2008] [Accepted: 11/06/2008] [Indexed: 01/09/2023] Open
Abstract
Pre-clinical and human neuropharmacological evidence suggests a role of cholinergic modulation of monoamines as a pathophysiological and therapeutic mechanism in Alzheimer's disease. The present study measured the effects of treatment with the cholinesterase inhibitor and nicotinic receptor modulator, galantamine, on the cerebral metabolic response to the selective serotonin reuptake inhibitor, citalopram. Seven probable Alzheimer's disease patients and seven demographically comparable controls underwent two positron emission tomography (PET) glucose metabolism scans, after administration of a saline placebo infusion (Day 1) and after citalopram (40 mg, IV, Day 2). The scan protocol was repeated in the Alzheimer's disease patients 2 months after titration to a 24 mg galantamine dose. At baseline, cerebral glucose metabolism was reduced in Alzheimer's disease patients relative to controls in right middle temporal, left posterior cingulate and parietal cortices (precuneus and inferior parietal lobule), as expected. Both groups demonstrated acute decreases in cerebral glucose metabolism after citalopram to a greater extent in the Alzheimer's disease patients. In the patients, relative to the controls, citalopram decreased glucose metabolism to a greater extent in middle frontal gyrus (bilaterally), left middle temporal gyrus and right posterior cingulate prior to treatment. Galantamine treatment alone increased metabolism in the right precuneus, right inferior parietal lobule and right middle occipital gyrus. In contrast, during galantamine treatment, citalopram increased metabolism in the right middle frontal gyrus, right post-central gyrus, right superior and middle temporal gyrus and right cerebellum. The combined cerebral metabolic effects of galantamine and citalopram suggest, consistent with preclinical data, a synergistic interaction of cholinergic and serotonergic systems.
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Affiliation(s)
- Gwenn S Smith
- Department of Psychiatry Research, The Zucker Hillside Hospital, Glen Oaks, NY 11004, USA.
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21
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Abstract
Frontal and basal ganglia infarcts and executive dysfunction are thought to be involved in the pathophysiology of poststroke emotional incontinence (PSEI). The study examined whether patients with PSEI have more frontal and/or basal ganglia infarcts and impairment in executive function. A total of 516 Chinese patients with acute ischemic stroke consecutively admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong were screened for PSEI 3 months after the index stroke. According to Kim's criteria, 39 (7.6%) had PSEI. Thirty-nine stroke patients without PSEI served as matched control group. The PSEI group had significantly more frontal and/or basal ganglia infarcts, had lower Chinese Frontal Assessment Battery scores, required more time to complete the Stroop Test, and made more omission and commission errors in the Go-NoGo test. There was no significant correlation between frontal or basal ganglia infarcts and executive function. The correlation between frontal infarct and severity of PSEI was .420. Further follow-up and functional imaging studies are warranted to explore the relationship between PSEI, brain infarcts, and executive dysfunction. (JINS, 2009, 15, 62-68.).
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22
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Abstract
PURPOSE OF REVIEW Neuropsychiatric disturbances in dementia are prevalent, and research is uncovering their neurobiological correlates. RECENT FINDINGS Late-onset depression appears to be associated with Alzheimer's disease pathology at autopsy, and lifetime depression episodes may worsen Alzheimer's disease pathology in the hippocampus. Vascular disease and elevated homocysteine increase risk for both late-onset depression and Alzheimer's disease and may partly mediate their relationship. Monoamine changes are robust finding in Alzheimer's disease and may account for many observed depression symptoms. Risk of psychosis of Alzheimer's disease appears to be increased by several genes also implicated in schizophrenia (e.g., catechol-O-methyltransferase, neuregulin-1). Psychosis in dementia with Lewy bodies appears to be related to cholinergic deficits. Alzheimer's disease is associated with changes in the circadian sleep-wake cycles, including decreased night-time melatonin. Sleep apnea may be related to apolipoprotein E genotype and impact cognition in Alzheimer's disease. Rapid eye movement sleep behavior disorder is intricately related to synucleinopathies, such as dementia with Lewy bodies, but synuclein changes may not totally explain this relationship. SUMMARY Neuropsychiatric disturbances are a core feature of dementia and worsen many clinical outcomes. Among the most validated syndromes are depression, psychosis, and sleep disturbance of Alzheimer's disease. Neuropathology, neuroimaging, and genetic studies increasingly provide insight into the origins of these psychiatric symptoms in dementia.
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Affiliation(s)
- Thomas W Meeks
- Division of Geriatric Psychiatry, Department of Psychiatry, University of California, San Diego, and Veterans Affairs San Diego Healthcare System, San Diego, California 92161, USA.
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Otmakhova NA, Lewey J, Asrican B, Lisman JE. Inhibition of perforant path input to the CA1 region by serotonin and noradrenaline. J Neurophysiol 2005; 94:1413-22. [PMID: 15888529 DOI: 10.1152/jn.00217.2005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bath-applied monoamines-dopamine (DA), serotonin (5-HT), and noradrenaline (NE)-strongly suppress the perforant path (PP) input to CA1 hippocampal region with very little effect on the Schaffer collaterals (SC) input. The effect of DA action on PP field excitatory postsynaptic potential (fEPSP) has been characterized in detail, but relatively little is known about the NE and 5-HT effects. Here we show that the maximal inhibition of the PP fEPSP by NE is approximately 55%, whereas 5-HT inhibition is weaker ( approximately 35%). The half-maximal inhibitory concentration of both 5-HT and NE is approximately 1 muM. Neither NE nor 5-HT affected paired-pulse facilitation, suggesting that the effect is not presynaptic. This is in contrast to DA, which does have a presynaptic effect. The NE effect was blocked by alpha2 antagonists, whereas the alpha1 antagonist corynanthine and beta-antagonist propranolol were ineffective. The effect of 5-HT was mimicked by the agonist, 5-carboxamidotryptamine maleate (5-CT), and not affected by adrenergic and dopaminergic antagonists. To determine the 5-HT receptors involved, we tested a number of 5-HT antagonists, but none produced a complete suppression of the 5-HT effect. Of these, only the 5-HT7 and 5-HT2 antagonists produced weak but significant inhibition of 5-HT effect. We conclude that NE inhibits the PP fEPSP through postsynaptic action on alpha2-adrenoceptors and that 5-HT7, 5-HT2, and some other receptor may be involved in 5-HT action in PP.
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Affiliation(s)
- Nonna A Otmakhova
- Department of Biology and Volen Center for Complex Systems, Brandeis University, Waltham, MA 02454, USA
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Holthoff VA, Beuthien-Baumann B, Kalbe E, Lüdecke S, Lenz O, Zündorf G, Spirling S, Schierz K, Winiecki P, Sorbi S, Herholz K. Regional cerebral metabolism in early Alzheimer's disease with clinically significant apathy or depression. Biol Psychiatry 2005; 57:412-21. [PMID: 15705358 DOI: 10.1016/j.biopsych.2004.11.035] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2004] [Revised: 11/08/2004] [Accepted: 11/18/2004] [Indexed: 11/26/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is clinically characterized by cognitive impairment and behavioral disturbances. The aim of the study was to identify regional alterations in brain function associated with neuropsychiatric symptoms in early AD. METHODS Patients underwent measures of cerebral glucose metabolism applying positron emission tomography (PET) and (18)F-fluorodeoxyglucose. Neuropsychiatric symptoms were assessed using the Neuropsychiatric Inventory (NPI). Positron emission tomography images of patients suffering a neuropsychiatric symptom of clinical significance (NPI subscore for a specific item >/=4 points) were compared with the images of patients without the specific symptom under study (NPI subscore for a specific item = 0 points). RESULTS A total of 53 patients with AD (Mini-Mental State Examination [MMSE] 22.5 +/- 2.94 points) entered the study. Of all symptoms, apathy and depression were most frequently encountered. The patient group with apathy (n = 17) revealed significant decreases in left orbitofrontal regions when compared with patients free of apathy. Depression of clinical significance (n = 10) was associated with hypometabolism in dorsolateral prefrontal regions. CONCLUSIONS These findings support the notion that different functional circuits underlie apathy and depression in early AD.
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Affiliation(s)
- Vjera A Holthoff
- Department of Psychiatry and Psychotherapy, Dresden University of Technology, Germany
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25
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Abstract
PURPOSE OF REVIEW Neuropsychiatric, or non-cognitive symptoms are increasingly recognized as manifestations of dementias. RECENT FINDINGS In Alzheimer's disease, recent advances have included the identification of behavioral profiles, differentiation of apathy and depression, characterization of risk factors for psychosis and its links to agitation and aggression, and an analysis of depressive symptoms in the absence of major depression. Functional neuroimaging data mainly supported the role of the anterior cingulate in apathy. The orbitofrontal and anterior cingulate tangle burden were associated with agitation, and increased orbitofrontal and mid-temporal muscarinic M2 receptors with psychosis and hallucinations. Selected genetic polymorphisms of dopamine and serotonin receptors or transporters were linked with aggression, hallucinations or psychosis. When compared with other dementias, individuals with frontotemporal dementia disclosed, as expected, different behaviors and particularly aberrant social behavior. The frequency of delusions and visual hallucinations was increased in Parkinson's disease, Parkinson's disease with dementia, and dementia with Lewy bodies, suggesting common mechanisms such as Lewy body pathology and cholinergic deficiency. The latter was supported by an improvement of these symptoms by cholinesterase inhibitors. SUMMARY Future research directions include both clinical and basic neuroscience investigations. The detection of early neuropsychiatric symptoms might be a marker for dementia, and the possible existence of a mild neuropsychiatric impairment syndrome should be explored. More longitudinal studies with pathological confirmation will facilitate correlations with neuropsychiatric symptoms. Functional neuroimaging and behavioral neurogenetics will permit in-vivo correlations and consequently help patient management and care.
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Affiliation(s)
- Frédéric Assal
- UCLA School of Medicine, Los Angeles, CA 90095-1769, USA
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