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Liao MH, Lin YK, Gau FY, Tseng CC, Wu DC, Hsu CY, Chung KH, Li RC, Hu CJ, Then CK, Shen SC. Antidepressant sertraline increases thioflavin-S and Congo red deposition in APPswe/PSEN1dE9 transgenic mice. Front Pharmacol 2024; 14:1260838. [PMID: 38259283 PMCID: PMC10800414 DOI: 10.3389/fphar.2023.1260838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 12/14/2023] [Indexed: 01/24/2024] Open
Abstract
Introduction: Depression is strongly associated with Alzheimer's disease (AD). Antidepressants are commonly used in patients before and after their diagnosis of AD. To date, the relationship between antidepressants and AD remains unclear. Methods: In our study, we administered sertraline or paroxetine to wild type (WT) and APPswe/PSEN1dE9 (APP/PSEN1) transgenic mouse models for up to 12 months. We quantified the drug concentrations using LC-MS/MS analysis and measured serum serotonin level using an ELISA assay. Additionally, we evaluated the amyloid burdens through thioflavin-S and Congo red stainings, and recognition memory using the novel object recognition test. Results: Our findings revealed that mice treated with paroxetine exhibited a significantly higher level of weight gain compared to the control group and increased mortality in APP/PSEN1 mice. After 12 months of antidepressant treatment, the sertraline level was measured at 289.8 ng/g for cerebellum, while the paroxetine level was 792.9 ng/g for cerebellum. Sertraline significantly increased thioflavin-S and Congo red depositions, along with gliosis, in both isocortex and hippocampus of APP/PSEN1 mice compared to the control group. Both antidepressants also led to a decreased recognition index in APP/PSEN1 mice. Conclusion: These findings suggest a potential role of sertraline in AD pathogenesis, emphasizing the need to reassess the use of these antidepressants in patients with AD.
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Affiliation(s)
- Ming-Hsuan Liao
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yen-Kuang Lin
- Graduate Institute of Athletics and Coaching Science, National Taiwan Sport University, Taoyuan, Taiwan
| | - Fong-Ying Gau
- School of Nursing, College of Nursing, Taipei Medical University, Taipei, Taiwan
| | - Chun-Che Tseng
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Da-Chih Wu
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chu-Yuan Hsu
- School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
| | - Kuo-Hsuan Chung
- Department of Psychiatry and Psychiatric Research Center, Taipei Medical University Hospital, Taipei, Taiwan
- Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Rung-Chi Li
- Division of Allergy and Immunology, University of Virginia, Charlottesville, VA, United States
| | - Chaur-Jong Hu
- Department of Neurology, Shuang Ho Hospital, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chee Kin Then
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
- Department of Radiation Oncology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
| | - Shing-Chuan Shen
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
- International Master/Ph.D. Program in Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Dermatology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
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Almkvist O, Johansson C, Laffita‐Mesa J, Thordardottir S, Graff C. APOE ε4 influences cognitive decline positively in APP and negatively in PSEN1 mutation carriers with autosomal-dominant Alzheimer's disease. Eur J Neurol 2022; 29:3580-3589. [PMID: 36039401 PMCID: PMC9826049 DOI: 10.1111/ene.15536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 07/03/2022] [Accepted: 08/17/2022] [Indexed: 01/11/2023]
Abstract
BACKGROUND AND PURPOSE The aim was to investigate the effect of APOE ε4 allele on cognitive decline in adAD. Presence of the APOE ε4 allele reduces age of symptom onset, increases disease progression, and lowers cognitive performance in sporadic Alzheimer's disease (AD), while the impact of the APOE ε4 allele in autosomal-dominant AD (adAD) is incompletely known. METHODS Mutation carriers (MCs; n = 39) and non-carriers (NCs; n = 40) from six adAD families harbouring a mutation in the APP (28 MCs and 25 NCs) or the PSEN1 genes (11 MCs and 15 NCs) underwent repeated cognitive assessments. A timeline of disease course was defined as years to expected age of clinical onset (YECO) based on history of disease onset in each family. The MC and NC groups were comparable with regard to demographics and prevalence of the APOE ε4 allele. The relationship between cognitive decline and YECO, YECO2 , education, APOE, and APOE-by-YECO interaction was analysed using linear mixed-effects models. RESULTS The trajectory of cognitive decline was significantly predicted by linear and quadratic YECO and education in MCs and was determined by age and education in NCs. Adding APOE ε4 allele (presence/absence) as a predictor did not change the results in the MC and NC groups. The outcome also remained the same for MCs and NCs after adding the APOE-by-YECO interaction as a predictor. Analyses of APP and PSEN1 MCs separately showed favourable APOE-by-YECO interaction in APP (less steep decline) and unfavourable interaction in PSEN1 (steeper decline), linked to the APOE ε4 allele. CONCLUSION The APOE ε4 allele influences cognitive decline positively in APP and negatively in PSEN1 mutation carriers with adAD, indicating a possible antagonistic pleiotropy.
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Affiliation(s)
- Ove Almkvist
- Divisions of Clinical Geriatrics, Department of Neurobiology Care Sciences and SocietyKarolinska InstituteteStockholmSweden
- Theme Inflammation and AgingKarolinska University Hospital StockholmStockholmSweden
| | - Charlotte Johansson
- Theme Inflammation and AgingKarolinska University Hospital StockholmStockholmSweden
- Divisions of Clinical Neurogeriatrics, Department of Neurobiology Care Sciences and SocietyKarolinska InstitutetStockholmSweden
| | - Jose Laffita‐Mesa
- Divisions of Clinical Neurogeriatrics, Department of Neurobiology Care Sciences and SocietyKarolinska InstitutetStockholmSweden
| | - Steinunn Thordardottir
- Divisions of Clinical Neurogeriatrics, Department of Neurobiology Care Sciences and SocietyKarolinska InstitutetStockholmSweden
| | - Caroline Graff
- Theme Inflammation and AgingKarolinska University Hospital StockholmStockholmSweden
- Divisions of Clinical Neurogeriatrics, Department of Neurobiology Care Sciences and SocietyKarolinska InstitutetStockholmSweden
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Consoli DC, Brady LJ, Bowman AB, Calipari ES, Harrison FE. Ascorbate deficiency decreases dopamine release in gulo -/- and APP/PSEN1 mice. J Neurochem 2021; 157:656-665. [PMID: 32797675 PMCID: PMC7882008 DOI: 10.1111/jnc.15151] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/30/2020] [Accepted: 07/31/2020] [Indexed: 12/14/2022]
Abstract
Dopamine (DA) has important roles in learning, memory, and motivational processes and is highly susceptible to oxidation. In addition to dementia, Alzheimer's disease (AD) patients frequently exhibit decreased motivation, anhedonia, and sleep disorders, suggesting deficits in dopaminergic neurotransmission. Vitamin C (ascorbate, ASC) is a critical antioxidant in the brain and is often depleted in AD patients as a result of disease-related oxidative stress and dietary deficiencies. To probe the effects of ASC deficiency and AD pathology on the DAergic system, gulo-/- mice, which like humans depend on dietary ASC to maintain adequate tissue levels, were crossed with APP/PSEN1 mice and provided sufficient or depleted ASC supplementation from weaning until 12 months of age. Ex vivo fast-scan cyclic voltammetry showed that chronic ASC depletion and APP/PSEN1 genotype both independently decreased dopamine release in the nucleus accumbens, a hub for motivational behavior and reward, while DA clearance was similar across all groups. In striatal tissue containing nucleus accumbens, low ASC treatment led to decreased levels of DA and its metabolites 3,4-dihydroxyohenyl-acetic acid (DOPAC), 3-methoxytyramine (3-MT), and homovanillic acid (HVA). Decreased enzyme activity observed through lower pTH/TH ratio was driven by a cumulative effect of ASC depletion and APP/PSEN1 genotype. Together the data show that deficits in dopaminergic neurotransmission resulting from age and disease status are magnified in conditions of low ASC which decrease DA availability during synaptic transmission. Such deficits may contribute to the non-cognitive behavioral changes observed in AD including decreased motivation, anhedonia, and sleep disorders.
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Affiliation(s)
- David C. Consoli
- Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN 37232 USA
| | - Lillian J. Brady
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt University School of Medicine, Nashville, TN 37232 USA
| | - Aaron B. Bowman
- School of Health Sciences, Purdue University, West Lafayette, IN 47907-2051, USA
| | - Erin S. Calipari
- Department of Pharmacology, Vanderbilt Center for Addiction Research, Vanderbilt University School of Medicine, Nashville, TN 37232 USA
| | - Fiona E. Harrison
- Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN 37232 USA
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Chaudhari K, Wang L, Kruse J, Winters A, Sumien N, Shetty R, Prah J, Liu R, Shi J, Forster M, Yang SH. Early loss of cerebellar Purkinje cells in human and a transgenic mouse model of Alzheimer's disease. Neurol Res 2021; 43:570-581. [PMID: 33688799 DOI: 10.1080/01616412.2021.1893566] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND The cerebellum's involvement in AD has been under-appreciated by historically labeling as a normal control in AD research. METHODS We determined the involvement of the cerebellum in AD progression. Postmortem human and APPswe/PSEN1dE9 mice cerebellums were used to assess the cerebellar Purkinje cells (PC) by immunohistochemistry. The locomotor and spatial cognitive functions were assessed in 4- to 5-month-old APPswe/PSEN1dE9 mice. Aβ plaque and APP processing were determined in APPswe/PSEN1dE9 mice at different age groups by immunohistochemistry and Western blot. RESULTS We observed loss of cerebellar PC in mild cognitive impairment and AD patients compared with cognitively normal controls. A strong trend towards PC loss was found in AD mice as early as 5 months. Impairment of balance beam and rotorod performance, but no spatial learning and memory dysfunction was observed in AD mice at 4-5 months. Aβ plaque in the cerebral cortex was evidenced in AD mice at 2 months and dramatically increased at 6 months. Less and smaller Aβ plaques were observed in the cerebellum than in the cerebrum of AD mice. Similar intracellular APP staining was observed in the cerebellum and cerebrum of AD mice at 2 to 10 months. Similar expression of full-length APP and C-terminal fragments were indicated in the cerebrum and cerebellum of AD mice during aging. DISCUSSION Our study in post-mortem human brains and transgenic AD mice provided neuropathological and functional evidence that cerebellar dysfunction may occur at the early stage of AD and likely independent of Aβ plaque.
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Affiliation(s)
- Kiran Chaudhari
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Linshu Wang
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Jonas Kruse
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Ali Winters
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Nathalie Sumien
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Ritu Shetty
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Jude Prah
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Ran Liu
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Jiong Shi
- Lou Ruvo Center for Brain Health, Cleveland Clinic Nevada, 888 W Bonneville Avenue, Las Vegas, NV USA
| | - Michael Forster
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
| | - Shao-Hua Yang
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX USA
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Audrain M, Haure-Mirande JV, Mleczko J, Wang M, Griffin JK, St George-Hyslop PH, Fraser P, Zhang B, Gandy S, Ehrlich ME. Reactive or transgenic increase in microglial TYROBP reveals a TREM2-independent TYROBP-APOE link in wild-type and Alzheimer's-related mice. Alzheimers Dement 2020; 17:149-163. [PMID: 33314529 PMCID: PMC7938663 DOI: 10.1002/alz.12256] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/19/2020] [Accepted: 11/03/2020] [Indexed: 12/12/2022]
Abstract
Introduction Microglial TYROBP (DAP12) is a network hub and driver in sporadic late‐onset Alzheimer's disease (AD). TYROBP is a cytoplasmic adaptor for TREM2 and other receptors, but little is known about its roles and actions in AD. Herein, we demonstrate that endogenous Tyrobp transcription is specifically increased in recruited microglia. Methods Using a novel transgenic mouse overexpressing TYROBP in microglia, we observed a decrease of the amyloid burden and an increase of TAU phosphorylation stoichiometry when crossed with APP/PSEN1 or MAPTP301S mice, respectively. Characterization of these mice revealed Tyrobp‐related modulation of apolipoprotein E (Apoe) transcription. We also showed that Tyrobp and Apoe mRNAs were increased in Trem2‐null microglia recruited around either amyloid beta deposits or a cortical stab injury. Conversely, microglial Apoe transcription was dramatically diminished when Tyrobp was absent. Conclusions Our results provide evidence that TYROBP‐APOE signaling does not require TREM2 and could be an initiating step in establishment of the disease‐associated microglia (DAM) phenotype.
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Affiliation(s)
- Mickael Audrain
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | | | - Justyna Mleczko
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Minghui Wang
- Department of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Jennifer K Griffin
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Peter H St George-Hyslop
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Paul Fraser
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Bin Zhang
- Department of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Sam Gandy
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,National Institute on Aging-Designated Alzheimer's Disease Research Center and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Research and Development, James J. Peters Veterans Affairs Medical Center, Bronx, New York, USA
| | - Michelle E Ehrlich
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Haure-Mirande JV, Audrain M, Fanutza T, Kim SH, Klein WL, Glabe C, Readhead B, Dudley JT, Blitzer RD, Wang M, Zhang B, Schadt EE, Gandy S, Ehrlich ME. Deficiency of TYROBP, an adapter protein for TREM2 and CR3 receptors, is neuroprotective in a mouse model of early Alzheimer's pathology. Acta Neuropathol 2017; 134:769-788. [PMID: 28612290 PMCID: PMC5645450 DOI: 10.1007/s00401-017-1737-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 05/21/2017] [Accepted: 06/02/2017] [Indexed: 01/28/2023]
Abstract
Conventional genetic approaches and computational strategies have converged on immune-inflammatory pathways as key events in the pathogenesis of late onset sporadic Alzheimer’s disease (LOAD). Mutations and/or differential expression of microglial specific receptors such as TREM2, CD33, and CR3 have been associated with strong increased risk for developing Alzheimer’s disease (AD). DAP12 (DNAX-activating protein 12)/TYROBP, a molecule localized to microglia, is a direct partner/adapter for TREM2, CD33, and CR3. We and others have previously shown that TYROBP expression is increased in AD patients and in mouse models. Moreover, missense mutations in the coding region of TYROBP have recently been identified in some AD patients. These lines of evidence, along with computational analysis of LOAD brain gene expression, point to DAP12/TYROBP as a potential hub or driver protein in the pathogenesis of AD. Using a comprehensive panel of biochemical, physiological, behavioral, and transcriptomic assays, we evaluated in a mouse model the role of TYROBP in early stage AD. We crossed an Alzheimer’s model mutant APPKM670/671NL/PSEN1Δexon9(APP/PSEN1) mouse model with Tyrobp−/− mice to generate AD model mice deficient or null for TYROBP (APP/PSEN1; Tyrobp+/− or APP/PSEN1; Tyrobp−/−). While we observed relatively minor effects of TYROBP deficiency on steady-state levels of amyloid-β peptides, there was an effect of Tyrobp deficiency on the morphology of amyloid deposits resembling that reported by others for Trem2−/− mice. We identified modulatory effects of TYROBP deficiency on the level of phosphorylation of TAU that was accompanied by a reduction in the severity of neuritic dystrophy. TYROBP deficiency also altered the expression of several AD related genes, including Cd33. Electrophysiological abnormalities and learning behavior deficits associated with APP/PSEN1 transgenes were greatly attenuated on a Tyrobp-null background. Some modulatory effects of TYROBP on Alzheimer’s-related genes were only apparent on a background of mice with cerebral amyloidosis due to overexpression of mutant APP/PSEN1. These results suggest that reduction of TYROBP gene expression and/or protein levels could represent an immune-inflammatory therapeutic opportunity for modulating early stage LOAD, potentially leading to slowing or arresting the progression to full-blown clinical and pathological LOAD.
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Affiliation(s)
| | - Mickael Audrain
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Tomas Fanutza
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Soong Ho Kim
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - William L Klein
- Department of Biochemistry, Northwestern University, Chicago, IL, 60611, USA
| | - Charles Glabe
- Department of Biochemistry and Molecular Biology, University of California at Irvine, Irvine, CA, 92697, USA
| | - Ben Readhead
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Joel T Dudley
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Robert D Blitzer
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Minghui Wang
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Bin Zhang
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Eric E Schadt
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Sam Gandy
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Department of Psychiatry and Alzheimer's Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Michelle E Ehrlich
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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Kennard JA, Harrison FE. Intravenous ascorbate improves spatial memory in middle-aged APP/PSEN1 and wild type mice. Behav Brain Res 2014; 264:34-42. [PMID: 24508240 PMCID: PMC3980584 DOI: 10.1016/j.bbr.2014.01.044] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Revised: 01/23/2014] [Accepted: 01/28/2014] [Indexed: 02/08/2023]
Abstract
The present study investigated the effects of a single intravenous (i.v.) dose of Vitamin C (ascorbate, ASC) on spatial memory in APP/PSEN1 mice, an Alzheimer's disease model. First, we confirmed the uptake time course in ASC-depleted gulo (-/-) mice, which cannot synthesize ASC. Differential tissue uptake was seen based on ASC transporter distribution. Liver (SVCT1 and SVCT2) ASC was elevated at 30, 60 and 120 min post-treatment (125 mg/kg, i.v.), whereas spleen (SVCT2) ASC increased at 60 and 120 min. There was no detectable change in cortical (SVCT2 at choroid plexus, and neurons) ASC within the 2-h interval, although the cortex preferentially retained ASC. APP/PSEN1 and wild type (WT) mice at three ages (3, 9, or 20 months) were treated with ASC (125 mg/kg, i.v.) or saline 45 min before testing on the Modified Y-maze, a two-trial task of spatial memory. Memory declined with age and ASC treatment improved performance in 9-month-old APP/PSEN1 and WT mice. APP/PSEN1 mice displayed no behavioral impairment relative to WT controls. Although dopamine and metabolite DOPAC decreased in the nucleus accumbens with age, and improved spatial memory was correlated with increased dopamine in saline treated mice, acute ASC treatment did not alter monoamine levels in the nucleus accumbens. These data show that the Modified Y-maze is sensitive to age-related deficits, but not additional memory deficits due to amyloid pathology in APP/PSEN1 mice. They also suggest improvements in short-term spatial memory were not due to changes in the neuropathological features of AD or monoamine signaling.
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Affiliation(s)
- John A Kennard
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
| | - Fiona E Harrison
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, United States
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