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Hernandez CM, McCuiston MA, Davis K, Halls Y, Carcamo Dal Zotto JP, Jackson NL, Dobrunz LE, King PH, McMahon LL. In a circuit necessary for cognition and emotional affect, Alzheimer's-like pathology associates with neuroinflammation, cognitive and motivational deficits in the young adult TgF344-AD rat. Brain Behav Immun Health 2024; 39:100798. [PMID: 39022628 PMCID: PMC11253229 DOI: 10.1016/j.bbih.2024.100798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Accepted: 05/21/2024] [Indexed: 07/20/2024] Open
Abstract
In addition to extracellular amyloid plaques, intracellular neurofibrillary tau tangles, and inflammation, cognitive and emotional affect perturbations are characteristic of Alzheimer's disease (AD). The cognitive and emotional domains impaired by AD include several forms of decision making (such as intertemporal choice), blunted motivation (increased apathy), and impaired executive function (such as working memory and cognitive flexibility). However, the interaction between these domains of the mind and their supporting neurobiological substrates at prodromal stages of AD, or whether these interactions can be predictive of AD severity (individual variability), remain unclear. In this study, we employed a battery of cognitive and emotional tests in the young adult (5-7 mo) transgenic Fisher-344 AD (TgF344-AD; TgAD) rat model of AD. We also assessed whether markers of inflammation or AD-like pathology in the prelimbic cortex (PrL) of the medial prefrontal cortex (mPFC), basolateral amygdala (BLA), or nucleus accumbens (NAc), all structures that directly support the aforementioned behaviors, were predictive of behavioral deficits. We found TgAD rats displayed maladaptive decision making, greater apathy, and impaired working memory that was indeed predicted by AD-like pathology in the relevant brain structures, even at an early age. Moreover, we report that the BLA is an early epicenter of inflammation, and notably, AD-like pathology in the PrL, BLA, and NAc was predictive of BLA inflammation. These results suggest that operant-based battery testing may be sensitive enough to determine pathology trajectories, including neuroinflammation, from early stages of AD.
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Affiliation(s)
- Caesar M. Hernandez
- Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, The University of Alabama at Birmingham, Birmingham, AL, USA
- Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, USA
| | - Macy A. McCuiston
- Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Kristian Davis
- Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Yolanda Halls
- Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Juan Pablo Carcamo Dal Zotto
- Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nateka L. Jackson
- Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, USA
- Department of Neuroscience, Medical University of South Carolina, USA
| | - Lynn E. Dobrunz
- Department of Neurobiology, The University of Alabama at Birmingham, USA
| | - Peter H. King
- Department of Neurology, The University of Alabama at Birmingham, USA
- Birmingham Veterans Affairs Medical Center, Birmingham, AL, USA
| | - Lori L. McMahon
- Department of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, USA
- Department of Neuroscience, Medical University of South Carolina, USA
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Amiri S, van den Berg M, Nazem-Zadeh MR, Verhoye M, Amiri M, Keliris GA. Nodal degree centrality in the default mode-like network of the TgF344-AD Alzheimer's disease rat model as a measure of early network alterations. NPJ AGING 2024; 10:29. [PMID: 38902224 PMCID: PMC11190202 DOI: 10.1038/s41514-024-00151-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 04/19/2024] [Indexed: 06/22/2024]
Abstract
This study investigates brain network alterations in the default mode-like network (DMLN) at early stages of disease progression in a rat model of Alzheimer's disease (AD) with application in the development of early diagnostic biomarkers of AD in translational studies. Thirteen male TgF344-AD (TG) rats, and eleven male wild-types (WT) littermates underwent longitudinal resting-state fMRI at the age of 4 and 6 months (pre and early-plaque stages of AD). Alterations in connectivity within DMLN were characterized by calculating the nodal degree (ND), a graph theoretical measure of centrality. The ND values of the left CA2 subregion of the hippocampus was found to be significantly lower in the 4-month-old TG cohort compared to the age-matched WT littermates. Moreover, a lower ND value (hypo-connectivity) was observed in the right prelimbic cortex (prL) and basal forebrain in the 6-month-old TG cohort, compared to the same age WT cohort. Indeed, the ND pattern in the DMLN in both TG and WT cohorts showed significant differences across the two time points that represent pre-plaque and early plaque stages of disease progression. Our findings indicate that lower nodal degree (hypo-connectivity) in the left CA2 in the pre-plaque stage of AD and hypo-connectivity between the basal forebrain and the DMLN regions in the early-plaque stage demonstrated differences in comparison to healthy controls. These results suggest that a graph-theoretical measure such as the nodal degree, can characterize brain networks and improve our insights into the mechanisms underlying Alzheimer's disease.
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Affiliation(s)
- Saba Amiri
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Monica van den Berg
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
- µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Mohammad-Reza Nazem-Zadeh
- Research Center for Molecular and Cellular Imaging, Tehran University of Medical Sciences, Tehran, Iran
- Department of neuroscience, Monash university, Melbourne, Vic, Australia
| | - Marleen Verhoye
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
- µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Mahmood Amiri
- Medical Technology Research Center, Institute of Health Technology, Kermanshah University of Medical Sciences, Kermanshah, Iran.
| | - Georgios A Keliris
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium.
- µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium.
- Institute of Computer Science, Hellas Foundation for Research & Technology - Hellas, Heraklion, Crete, Greece.
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Wan J, Ma L, Jiao X, Dong W, Lin J, Qiu Y, Wu W, Liu Q, Chen C, Huang H, Li S, Zheng H, Wu Y. Impaired synaptic plasticity and decreased excitability of hippocampal glutamatergic neurons mediated by BDNF downregulation contribute to cognitive dysfunction in mice induced by repeated neonatal exposure to ketamine. CNS Neurosci Ther 2024; 30:e14604. [PMID: 38332635 PMCID: PMC10853651 DOI: 10.1111/cns.14604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 12/22/2023] [Accepted: 01/03/2024] [Indexed: 02/10/2024] Open
Abstract
AIM Repeated exposure to ketamine during the neonatal period in mice leads to cognitive impairments in adulthood. These impairments are likely caused by synaptic plasticity and excitability damage. We investigated the precise role of brain-derived neurotrophic factor (BDNF) in the cognitive impairments induced by repeated ketamine exposure during the neonatal period. METHODS We evaluated the cognitive function of mice using the Morris water maze test and novel object recognition test. Western blotting and immunofluorescence were used to detect the protein levels of BDNF. Western blotting, Golgi-Cox staining, transmission electron microscopy, and long-term potentiation (LTP) recordings were used to assess synaptic plasticity in the hippocampus. The excitability of neurons was evaluated using c-Fos. In the intervention experiment, pAdeno-CaMKIIα-BDNF-mNeuronGreen was injected into the hippocampal CA1 region of mice to increase the level of BDNF. The excitability of neurons was enhanced using a chemogenetic approach. RESULTS Our findings suggest that cognitive impairments in mice repeatedly exposed to ketamine during the neonatal period are associated with downregulated BDNF protein level, synaptic plasticity damage, and decreased excitability of glutamatergic neurons in the hippocampal CA1 region. Furthermore, the specific upregulation of BDNF in glutamatergic neurons of the hippocampal CA1 region and the enhancement of excitability can improve impaired synaptic plasticity and cognitive function in mice. CONCLUSION BDNF downregulation mediates synaptic plasticity and excitability damage, leading to cognitive impairments in adulthood following repeated ketamine exposure during the neonatal period.
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Affiliation(s)
- Jie Wan
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Linhui Ma
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
- Department of Anesthesiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Xinhao Jiao
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Wei Dong
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Jiatao Lin
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Yongkang Qiu
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Weifeng Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Qiang Liu
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Chen Chen
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - He Huang
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
| | - Shuai Li
- Department of Anesthesiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Hui Zheng
- Department of Anesthesiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Yuqing Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Jiangsu Province Key Laboratory of Anesthesia and Analgesia Application Technology, NMPA Key Laboratory for Research and Evaluation of Narcotic and Psychotropic DrugsXuzhou Medical UniversityXuzhouChina
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Xu F, Chen A, Pan S, Wu Y, He H, Han Z, Lu L, Orgil B, Chi X, Yang C, Jia S, Yu C, Mi J. Systems genetics analysis reveals the common genetic basis for pain sensitivity and cognitive function. CNS Neurosci Ther 2024; 30:e14557. [PMID: 38421132 PMCID: PMC10850811 DOI: 10.1111/cns.14557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 10/31/2023] [Accepted: 11/25/2023] [Indexed: 03/02/2024] Open
Abstract
BACKGROUND There is growing evidence of a strong correlation between pain sensitivity and cognitive function under both physiological and pathological conditions. However, the detailed mechanisms remain largely unknown. In the current study, we sought to explore candidate genes and common molecular mechanisms underlying pain sensitivity and cognitive function with a transcriptome-wide association study using recombinant inbred mice from the BXD family. METHODS The pain sensitivity determined by Hargreaves' paw withdrawal test and cognition-related phenotypes were systematically analyzed in 60 strains of BXD mice and correlated with hippocampus transcriptomes, followed by quantitative trait locus (QTL) mapping and systems genetics analysis. RESULTS The pain sensitivity showed significant variability across the BXD strains and co-varies with cognitive traits. Pain sensitivity correlated hippocampual genes showed a significant involvement in cognition-related pathways, including glutamatergic synapse, and PI3K-Akt signaling pathway. Moreover, QTL mapping identified a genomic region on chromosome 4, potentially regulating the variation of pain sensitivity. Integrative analysis of expression QTL mapping, correlation analysis, and Bayesian network modeling identified Ring finger protein 20 (Rnf20) as the best candidate. Further pathway analysis indicated that Rnf20 may regulate the expression of pain sensitivity and cognitive function through the PI3K-Akt signaling pathway, particularly through interactions with genes Ppp2r2b, Ppp2r5c, Col9a3, Met, Rps6, Tnc, and Kras. CONCLUSIONS Our study demonstrated that pain sensitivity is associated with genetic background and Rnf20-mediated PI3K-Akt signaling may involve in the regulation of pain sensitivity and cognitive functions.
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Affiliation(s)
- Fuyi Xu
- Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and TreatmentBinzhou Medical UniversityYantaiChina
| | - Anran Chen
- The Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantaiChina
| | - Shuijing Pan
- Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and TreatmentBinzhou Medical UniversityYantaiChina
| | - Yingying Wu
- Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and TreatmentBinzhou Medical UniversityYantaiChina
| | - Hongjie He
- Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and TreatmentBinzhou Medical UniversityYantaiChina
| | - Zhe Han
- Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and TreatmentBinzhou Medical UniversityYantaiChina
| | - Lu Lu
- University of Tennessee Health Science CenterMemphisTennesseeUSA
| | | | - XiaoDong Chi
- Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and TreatmentBinzhou Medical UniversityYantaiChina
| | - Cunhua Yang
- Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and TreatmentBinzhou Medical UniversityYantaiChina
| | - Shushan Jia
- Department of AnesthesiologyYanTai Affiliated Hospital of BinZhou Medical UniversityYantaiChina
| | - Cuicui Yu
- The Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantaiChina
| | - Jia Mi
- Shandong Technology Innovation Center of Molecular Targeting and Intelligent Diagnosis and TreatmentBinzhou Medical UniversityYantaiChina
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Ceyzériat K, Jaques E, Gloria Y, Badina A, Millet P, Koutsouvelis N, Dipasquale G, Frisoni GB, Zilli T, Garibotto V, Tournier BB. Low-Dose Radiation Therapy Impacts Microglial Inflammatory Response without Modulating Amyloid Load in Female TgF344-AD Rats. J Alzheimers Dis 2024; 98:1001-1016. [PMID: 38489181 DOI: 10.3233/jad-231153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2024]
Abstract
Background Low-dose radiation therapy (LD-RT) has demonstrated in preclinical and clinical studies interesting properties in the perspective of targeting Alzheimer's disease (AD), including anti-amyloid and anti-inflammatory effects. Nevertheless, studies were highly heterogenous with respect to total doses, fractionation protocols, sex, age at the time of treatment and delay post treatment. Recently, we demonstrated that LD-RT reduced amyloid peptides and inflammatory markers in 9-month-old TgF344-AD (TgAD) males. Objective As multiple studies demonstrated a sex effect in AD, we wanted to validate that LD-RT benefits are also observed in TgAD females analyzed at the same age. Methods Females were bilaterally treated with 2 Gy×5 daily fractions, 2 Gy×5 weekly fractions, or 10 fractions of 1 Gy delivered twice a week. The effect of each treatment on amyloid load and inflammation was evaluated using immunohistology and biochemistry. Results A daily treatment did not affect amyloid and reduced only microglial-mediated inflammation markers, the opposite of the results obtained in our previous male study. Moreover, altered fractionations (2 Gy×5 weekly fractions or 10 fractions of 1 Gy delivered twice a week) did not influence the amyloid load or neuroinflammatory response in females. Conclusions A daily treatment consequently appears to be the most efficient for AD. This study also shows that the anti-amyloid and anti-inflammatory response to LD-RT are, at least partly, two distinct mechanisms. It also emphasizes the necessity to assess the sex impact when evaluating responses in ongoing pilot clinical trials testing LD-RT against AD.
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Affiliation(s)
- Kelly Ceyzériat
- Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
- Faculty of Medicine, Geneva University, Geneva, Switzerland
- Diagnostic Department, Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and NIMTLab, Faculty of Medicine, Geneva University, Geneva, Switzerland
- CIBM Center for BioMedical Imaging, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Emma Jaques
- Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
- Faculty of Medicine, Geneva University, Geneva, Switzerland
| | - Yesica Gloria
- Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
- Faculty of Medicine, Geneva University, Geneva, Switzerland
- Bertarelli Foundation Gene Therapy Platform, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland
| | - Aurélien Badina
- Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
- Faculty of Medicine, Geneva University, Geneva, Switzerland
| | - Philippe Millet
- Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
- Faculty of Medicine, Geneva University, Geneva, Switzerland
| | - Nikolaos Koutsouvelis
- Department of Oncology, Division of Radiation Oncology, Geneva University Hospitals, Geneva, Switzerland
| | - Giovanna Dipasquale
- Department of Oncology, Division of Radiation Oncology, Geneva University Hospitals, Geneva, Switzerland
| | - Giovanni B Frisoni
- Faculty of Medicine, Geneva University, Geneva, Switzerland
- Diagnostic Department, Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and NIMTLab, Faculty of Medicine, Geneva University, Geneva, Switzerland
| | - Thomas Zilli
- Faculty of Medicine, Geneva University, Geneva, Switzerland
- Department of Oncology, Division of Radiation Oncology, Geneva University Hospitals, Geneva, Switzerland
- Department of Radiation Oncology, Oncology Institute of Southern Switzerland, EOC, Bellinzona, Switzerland
- Facoltà di Scienze Biomediche, Università della Svizzera Italiana, Lugano, Switzerland
| | - Valentina Garibotto
- Faculty of Medicine, Geneva University, Geneva, Switzerland
- Diagnostic Department, Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and NIMTLab, Faculty of Medicine, Geneva University, Geneva, Switzerland
- CIBM Center for BioMedical Imaging, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Benjamin B Tournier
- Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
- Faculty of Medicine, Geneva University, Geneva, Switzerland
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Moradi F, van den Berg M, Mirjebreili M, Kosten L, Verhoye M, Amiri M, Keliris GA. Early classification of Alzheimer's disease phenotype based on hippocampal electrophysiology in the TgF344-AD rat model. iScience 2023; 26:107454. [PMID: 37599835 PMCID: PMC10432721 DOI: 10.1016/j.isci.2023.107454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 04/27/2023] [Accepted: 07/19/2023] [Indexed: 08/22/2023] Open
Abstract
The hippocampus plays a vital role in navigation, learning, and memory, and is affected in Alzheimer's disease (AD). This study investigated the classification of AD-transgenic rats versus wild-type littermates using electrophysiological activity recorded from the hippocampus at an early, presymptomatic stage of the disease (6 months old) in the TgF344-AD rat model. The recorded signals were filtered into low frequency (LFP) and high frequency (spiking activity) signals, and machine learning classifiers were employed to identify the rat genotype (TG vs. WT). By analyzing specific frequency bands in the low frequency signals and calculating distance metrics between spike trains in the high frequency signals, accurate classification was achieved. Gamma band power emerged as a valuable signal for classification, and combining information from both low and high frequency signals improved the accuracy further. These findings provide valuable insights into the early stage effects of AD on different regions of the hippocampus.
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Affiliation(s)
- Faraz Moradi
- Faculty of Engineering, University of Ottawa, Ottawa, ON, Canada
| | - Monica van den Berg
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
- μNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | | | - Lauren Kosten
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
- μNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Marleen Verhoye
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
- μNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Mahmood Amiri
- Medical Technology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Georgios A. Keliris
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
- μNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Institute of Computer Science, Foundation for Research & Technology - Hellas, Heraklion, Crete, Greece
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Lenz M, Eichler A, Kruse P, Galanis C, Kleidonas D, Andrieux G, Boerries M, Jedlicka P, Müller U, Deller T, Vlachos A. The Amyloid Precursor Protein Regulates Synaptic Transmission at Medial Perforant Path Synapses. J Neurosci 2023; 43:5290-5304. [PMID: 37369586 PMCID: PMC10359033 DOI: 10.1523/jneurosci.1824-22.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 05/20/2023] [Accepted: 05/24/2023] [Indexed: 06/29/2023] Open
Abstract
The perforant path provides the primary cortical excitatory input to the hippocampus. Because of its important role in information processing and coding, entorhinal projections to the dentate gyrus have been studied in considerable detail. Nevertheless, synaptic transmission between individual connected pairs of entorhinal stellate cells and dentate granule cells remains to be characterized. Here, we have used mouse organotypic entorhino-hippocampal tissue cultures of either sex, in which the entorhinal cortex (EC) to dentate granule cell (GC; EC-GC) projection is present, and EC-GC pairs can be studied using whole-cell patch-clamp recordings. By using cultures of wild-type mice, the properties of EC-GC synapses formed by afferents from the lateral and medial entorhinal cortex were compared, and differences in short-term plasticity were identified. As the perforant path is severely affected in Alzheimer's disease, we used tissue cultures of amyloid precursor protein (APP)-deficient mice to examine the role of APP at this synapse. APP deficiency altered excitatory neurotransmission at medial perforant path synapses, which was accompanied by transcriptomic and ultrastructural changes. Moreover, presynaptic but not postsynaptic APP deletion through the local injection of Cre-expressing adeno-associated viruses in conditional APPflox/flox tissue cultures increased the neurotransmission efficacy at perforant path synapses. In summary, these data suggest a physiological role for presynaptic APP at medial perforant path synapses that may be adversely affected under altered APP processing conditions.SIGNIFICANCE STATEMENT The hippocampus receives input from the entorhinal cortex via the perforant path. These projections to hippocampal dentate granule cells are of utmost importance for learning and memory formation. Although there is detailed knowledge about perforant path projections, the functional synaptic properties at the level of individual connected pairs of neurons are not well understood. In this study, we investigated the role of APP in mediating functional properties and transmission rules in individually connected neurons using paired whole-cell patch-clamp recordings and genetic tools in organotypic tissue cultures. Our results show that presynaptic APP expression limits excitatory neurotransmission via the perforant path, which could be compromised in pathologic conditions such as Alzheimer's disease.
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Affiliation(s)
- Maximilian Lenz
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Hannover Medical School, Institute of Neuroanatomy and Cell Biology, 30625 Hannover, Germany
| | - Amelie Eichler
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Pia Kruse
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Christos Galanis
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Dimitrios Kleidonas
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Spemann Graduate School of Biology and Medicine, University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Geoffroy Andrieux
- Institute of Medical Bioinformatics and Systems Medicine, Medical Center, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Melanie Boerries
- Institute of Medical Bioinformatics and Systems Medicine, Medical Center, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- German Cancer Consortium, German Cancer Research Center, 69120 Heidelberg, Germany
| | - Peter Jedlicka
- Interdisciplinary Centre for 3Rs in Animal Research, Faculty of Medicine, Justus-Liebig-University, 35392 Giessen, Germany
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
- Frankfurt Institute for Advanced Studies, 60438 Frankfurt am Main, Germany
| | - Ulrike Müller
- Institute of Pharmacy and Molecular Biotechnology, Functional Genomics, Ruprecht-Karls University Heidelberg, 69120 Heidelberg, Germany
| | - Thomas Deller
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany
| | - Andreas Vlachos
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Center for Basics in Neuromodulation, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Center BrainLinks-BrainTools, University of Freiburg, 79104 Freiburg, Germany
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8
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Irwin AB, Martina V, Jago SCS, Bahabry R, Schreiber AM, Lubin FD. The lncRNA Neat1 is associated with astrocyte reactivity and memory deficits in a mouse model of Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.03.539260. [PMID: 37205548 PMCID: PMC10187170 DOI: 10.1101/2023.05.03.539260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Dysregulation of long non-coding RNAs (lncRNAs) have been associated with Alzheimer's disease (AD). However, the functional role of lncRNAs in AD remains unclear. Here, we report a crucial role for the lncRNA Neat1 in astrocyte dysfunction and memory deficits associated with AD. Transcriptomics analysis show abnormally high expression levels of NEAT1 in the brains of AD patients relative to aged-matched healthy controls, with the most significantly elevated levels in glial cells. In a human transgenic APP-J20 (J20) mouse model of AD, RNA-fluorescent in situ hybridization characterization of Neat1 expression in hippocampal astrocyte versus non-astrocyte cell populations revealed a significant increase in Neat1 expression in astrocytes of male, but not female, mice. This corresponded with increased seizure susceptibility in J20 male mice. Interestingly, Neat1 deficiency in the dCA1 in J20 male mice did not alter seizure threshold. Mechanistically, Neat1 deficiency in the dorsal area CA1 of the hippocampus (dCA1) J20 male mice significantly improved hippocampus-dependent memory. Neat1 deficiency also remarkably reduced astrocyte reactivity markers suggesting that Neat1 overexpression is associated with astrocyte dysfunction induced by hAPP/Aβ in the J20 mice. Together, these findings indicate that abnormal Neat1 overexpression may contribute to memory deficits in the J20 AD model not through altered neuronal activity, but through astrocyte dysfunction.
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Affiliation(s)
- Ashleigh B Irwin
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294 USA
| | - Verdion Martina
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294 USA
| | - Silvienne C Sint Jago
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294 USA
| | - Rudhab Bahabry
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294 USA
| | - Anna Maria Schreiber
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294 USA
| | - Farah D. Lubin
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294 USA
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Burgos DF, Sciaccaluga M, Worby CA, Zafra-Puerta L, Iglesias-Cabeza N, Sánchez-Martín G, Prontera P, Costa C, Serratosa JM, Sánchez MP. Epm2a R240X knock-in mice present earlier cognitive decline and more epileptic activity than Epm2a -/- mice. Neurobiol Dis 2023; 181:106119. [PMID: 37059210 DOI: 10.1016/j.nbd.2023.106119] [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: 12/29/2022] [Revised: 04/02/2023] [Accepted: 04/05/2023] [Indexed: 04/16/2023] Open
Abstract
Lafora disease is a rare recessive form of progressive myoclonic epilepsy, usually diagnosed during adolescence. Patients present with myoclonus, neurological deterioration, and generalized tonic-clonic, myoclonic, or absence seizures. Symptoms worsen until death, usually within the first ten years of clinical onset. The primary histopathological hallmark is the formation of aberrant polyglucosan aggregates called Lafora bodies in the brain and other tissues. Lafora disease is caused by mutations in either the EPM2A gene, encoding laforin, or the EPM2B gene, coding for malin. The most frequent EPM2A mutation is R241X, which is also the most prevalent in Spain. The Epm2a-/- and Epm2b-/- mouse models of Lafora disease show neuropathological and behavioral abnormalities similar to those seen in patients, although with a milder phenotype. To obtain a more accurate animal model, we generated the Epm2aR240X knock-in mouse line with the R240X mutation in the Epm2a gene, using genetic engineering based on CRISPR-Cas9 technology. Epm2aR240X mice exhibit most of the alterations reported in patients, including the presence of LBs, neurodegeneration, neuroinflammation, interictal spikes, neuronal hyperexcitability, and cognitive decline, despite the absence of motor impairments. The Epm2aR240X knock-in mouse displays some symptoms that are more severe that those observed in the Epm2a-/- knock-out, including earlier and more pronounced memory loss, increased levels of neuroinflammation, more interictal spikes and increased neuronal hyperexcitability, symptoms that more precisely resemble those observed in patients. This new mouse model can therefore be specifically used to evaluate how new therapies affects these features with greater precision.
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Affiliation(s)
- Daniel F Burgos
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain; Program in Neuroscience, Autonoma de Madrid University-Cajal Institute, Madrid 28029, Spain
| | - Miriam Sciaccaluga
- Section of Neurology, Department of Medicine and Surgery, University of Perugia, Perugia 06132, Italy; Fondazione Malattie Rare Mauro Baschirotto BIRD Onlus, Longare (VI), Italy
| | - Carolyn A Worby
- University of California at San Diego, 9500 Gilman Drive, La Jolla CA92093-0721, USA
| | - Luis Zafra-Puerta
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain; Program in Neuroscience, Autonoma de Madrid University-Cajal Institute, Madrid 28029, Spain; Fondazione Malattie Rare Mauro Baschirotto BIRD Onlus, Longare (VI), Italy
| | - Nerea Iglesias-Cabeza
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain
| | - Gema Sánchez-Martín
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain
| | - Paolo Prontera
- Medical Genetics Unit, S. Maria della Misericordia Hospital, Perugia 06132, Italy
| | - Cinzia Costa
- Section of Neurology, S. Maria della Misericordia Hospital, Department of Medicine and Surgery, University of Perugia, Perugia 06132, Italy
| | - José M Serratosa
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain
| | - Marina P Sánchez
- Laboratory of Neurology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid 28040, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid 28029, Spain.
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10
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Bac B, Hicheri C, Weiss C, Buell A, Vilcek N, Spaeni C, Geula C, Savas JN, Disterhoft JF. The TgF344-AD rat: behavioral and proteomic changes associated with aging and protein expression in a transgenic rat model of Alzheimer's disease. Neurobiol Aging 2023; 123:98-110. [PMID: 36657371 PMCID: PMC10118906 DOI: 10.1016/j.neurobiolaging.2022.12.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/20/2022] [Accepted: 12/28/2022] [Indexed: 01/01/2023]
Abstract
Animal models of Alzheimer's Disease (AD) are attractive tools for preclinical, prodromal drug testing. The TgF344-AD (Tg) rat exhibits cognitive deficits and 5 major hallmarks of AD. Here we show that spatial water maze (WMZ) memory deficits and proteomic differences in dorsal CA1 were present in young Tg rats. Aged learning-unimpaired (AU) and aged learning-impaired (AI) proteome associated changes were identified and differed by sex. Levels of phosphorylated tau, reactive astrocytes and microglia were significantly increased in aged Tg rats and correlated with the WMZ learning index (LI); in contrast, no significant correlation was present between amyloid plaques or insoluble Aβ levels and LI. Neuroinflammatory markers were also significantly correlated with LI and increased in female Tg rats. The anti-inflammatory marker, triggering receptor expressed on myeloid cells-2 (TREM2), was significantly reduced in aged impaired Tg rats and correlated with LI. Identifying and understanding mechanisms that allow for healthy aging by overcoming genetic drivers for AD, and/or promoting drivers for successful aging, are important for developing successful therapeutics against AD.
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Affiliation(s)
- Birsu Bac
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Cheima Hicheri
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Craig Weiss
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Amelia Buell
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Natalia Vilcek
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Claudia Spaeni
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Changiz Geula
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Jeffrey N Savas
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - John F Disterhoft
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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11
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van den Berg M, Toen D, Verhoye M, Keliris GA. Alterations in theta-gamma coupling and sharp wave-ripple, signs of prodromal hippocampal network impairment in the TgF344-AD rat model. Front Aging Neurosci 2023; 15:1081058. [PMID: 37032829 PMCID: PMC10075364 DOI: 10.3389/fnagi.2023.1081058] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 02/27/2023] [Indexed: 04/11/2023] Open
Abstract
Alzheimer's disease (AD) is a severe neurodegenerative disorder caused by the accumulation of toxic proteins, amyloid-beta (Aβ) and tau, which eventually leads to dementia. Disease-modifying therapies are still lacking, due to incomplete insights into the neuropathological mechanisms of AD. Synaptic dysfunction is known to occur before cognitive symptoms become apparent and recent studies have demonstrated that imbalanced synaptic signaling drives the progression of AD, suggesting that early synaptic dysfunction could be an interesting therapeutic target. Synaptic dysfunction results in altered oscillatory activity, which can be detected with electroencephalography and electrophysiological recordings. However, the majority of these studies have been performed at advanced stages of AD, when extensive damage and cognitive symptoms are already present. The current study aimed to investigate if the hippocampal oscillatory activity is altered at pre-plaque stages of AD. The rats received stereotactic surgery to implant a laminar electrode in the CA1 layer of the right hippocampus. Electrophysiological recordings during two consecutive days in an open field were performed in 4-5-month-old TgF344-AD rats when increased concentrations of soluble Aβ species were observed in the brain, in the absence of Aβ-plaques. We observed a decreased power of high theta oscillations in TgF344-AD rats compared to wild-type littermates. Sharp wave-ripple (SWR) analysis revealed an increased SWR power and a decreased duration of SWR during quiet wake in TgF344-AD rats. The alterations in properties of SWR and the increased power of fast oscillations are suggestive of neuronal hyperexcitability, as has been demonstrated to occur during presymptomatic stages of AD. In addition, decreased strength of theta-gamma coupling, an important neuronal correlate of memory encoding, was observed in the TgF344-AD rats. Theta-gamma phase amplitude coupling has been associated with memory encoding and the execution of cognitive functions. Studies have demonstrated that mild cognitive impairment patients display decreased coupling strength, similar to what is described here. The current study demonstrates altered hippocampal network activity occurring at pre-plaque stages of AD and provides insights into prodromal network dysfunction in AD. The alterations observed could aid in the detection of AD during presymptomatic stages.
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Affiliation(s)
- Monica van den Berg
- Bio-Imaging Lab, University of Antwerp, Wilrijk, Belgium
- μNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
- *Correspondence: Monica van den Berg, ; Georgios A. Keliris,
| | - Daniëlle Toen
- Bio-Imaging Lab, University of Antwerp, Wilrijk, Belgium
- μNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Marleen Verhoye
- Bio-Imaging Lab, University of Antwerp, Wilrijk, Belgium
- μNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Georgios A. Keliris
- Bio-Imaging Lab, University of Antwerp, Wilrijk, Belgium
- μNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
- Institute of Computer Science, Foundation for Research and Technology – Hellas, Heraklion, Crete, Greece
- *Correspondence: Monica van den Berg, ; Georgios A. Keliris,
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Chaudry O, Ndukwe K, Xie L, Figueiredo-Pereira M, Serrano P, Rockwell P. Females exhibit higher GluA2 levels and outperform males in active place avoidance despite increased amyloid plaques in TgF344-Alzheimer's rats. Sci Rep 2022; 12:19129. [PMID: 36352024 PMCID: PMC9646806 DOI: 10.1038/s41598-022-23801-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 11/05/2022] [Indexed: 11/11/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease that is most prevalent in females. While estrogen provides neuroprotection in females, sex mediated differences in the development of AD pathology are not fully elucidated. Therefore, comparing events between sexes in early-stage AD pathology may reveal more effective therapeutic targets of intervention. To address sex differences, we analyzed early-stage 9-month male and female TgF344-AD (Tg-AD) rats, an AD model carrying the APPswe and Presenilin 1 (PS1ΔE9) mutations that develops progressive age-dependent AD pathology similar to humans. Tg-AD females significantly outperformed Tg-AD males in the active place avoidance (aPAT) test that assesses hippocampal-dependent spatial learning and memory. However, comparisons between Tg-AD male or female rats and their WT counterparts showed significant deficits for female but not male rats. Nevertheless, Tg-AD females experienced significantly less hippocampal neuronal loss with higher GluA2 subunit levels than Tg-AD males. Unexpectedly, Tg-AD females displayed higher levels of hippocampal amyloid plaques than Tg-AD males. Thus, we propose that GluA2 may provide a neuroprotective function for Tg-AD females in our rat model by mitigating cognitive impairment independently of amyloid plaques. Elucidating this protective mechanism in AD could lead to new targets for early intervention.
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Affiliation(s)
- Osama Chaudry
- Department of Biological Sciences, Hunter College CUNY, New York, NY, USA
| | - Kelechi Ndukwe
- Department of Biological Sciences, Hunter College CUNY, New York, NY, USA
- PhD Program in Neuroscience, The Graduate Center CUNY, New York, NY, USA
| | - Lei Xie
- Department of Computer Sciences, Hunter College CUNY, New York, NY, USA
| | | | - Peter Serrano
- Department of Psychology, Hunter College CUNY, New York, NY, USA
| | - Patricia Rockwell
- Department of Biological Sciences, Hunter College CUNY, New York, NY, USA.
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13
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Spatio-temporal metabolic rewiring in the brain of TgF344-AD rat model of Alzheimer's disease. Sci Rep 2022; 12:16958. [PMID: 36216838 PMCID: PMC9550832 DOI: 10.1038/s41598-022-20962-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 09/21/2022] [Indexed: 12/29/2022] Open
Abstract
Brain damage associated with Alzheimer's disease (AD) occurs even decades before the symptomatic onset, raising the need to investigate its progression from prodromal stages. In this context, animal models that progressively display AD pathological hallmarks (e.g. TgF344-AD) become crucial. Translational technologies, such as magnetic resonance spectroscopy (MRS), enable the longitudinal metabolic characterization of this disease. However, an integrative approach is required to unravel the complex metabolic changes underlying AD progression, from early to advanced stages. TgF344-AD and wild-type (WT) rats were studied in vivo on a 7 Tesla MRI scanner, for longitudinal quantitative assessment of brain metabolic profile changes using MRS. Disease progression was investigated at 4 time points, from 9 to 18 months of age, and in 4 regions: cortex, hippocampus, striatum, and thalamus. Compared to WT, TgF344-AD rats replicated common findings in AD patients, including decreased N-acetylaspartate in the cortex, hippocampus and thalamus, and decreased glutamate in the thalamus and striatum. Different longitudinal evolution of metabolic concentration was observed between TgF344-AD and WT groups. Namely, age-dependent trajectories differed between groups for creatine in the cortex and thalamus and for taurine in cortex, with significant decreases in Tg344-AD animals; whereas myo-inositol in the thalamus and striatum showed greater increase along time in the WT group. Additional analysis revealed divergent intra- and inter-regional metabolic coupling in each group. Thus, in cortex, strong couplings of N-acetylaspartate and creatine with myo-inositol in WT, but with taurine in TgF344-AD rats were observed; whereas in the hippocampus, myo-inositol, taurine and choline compounds levels were highly correlated in WT but not in TgF344-AD animals. Furthermore, specific cortex-hippocampus-striatum metabolic crosstalks were found for taurine levels in the WT group but for myo-inositol levels in the TgF344-AD rats. With a systems biology perspective of metabolic changes in AD pathology, our results shed light into the complex spatio-temporal metabolic rewiring in this disease, reported here for the first time. Age- and tissue-dependent imbalances between myo-inositol, taurine and other metabolites, such as creatine, unveil their role in disease progression, while pointing to the inadequacy of the latter as an internal reference for quantification.
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14
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van den Berg M, Adhikari MH, Verschuuren M, Pintelon I, Vasilkovska T, Van Audekerke J, Missault S, Heymans L, Ponsaerts P, De Vos WH, Van der Linden A, Keliris GA, Verhoye M. Altered basal forebrain function during whole-brain network activity at pre- and early-plaque stages of Alzheimer's disease in TgF344-AD rats. Alzheimers Res Ther 2022; 14:148. [PMID: 36217211 PMCID: PMC9549630 DOI: 10.1186/s13195-022-01089-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/22/2022] [Indexed: 11/10/2022]
Abstract
BACKGROUND Imbalanced synaptic transmission appears to be an early driver in Alzheimer's disease (AD) leading to brain network alterations. Early detection of altered synaptic transmission and insight into mechanisms causing early synaptic alterations would be valuable treatment strategies. This study aimed to investigate how whole-brain networks are influenced at pre- and early-plague stages of AD and if these manifestations are associated with concomitant cellular and synaptic deficits. METHODS: To this end, we used an established AD rat model (TgF344-AD) and employed resting state functional MRI and quasi-periodic pattern (QPP) analysis, a method to detect recurrent spatiotemporal motifs of brain activity, in parallel with state-of-the-art immunohistochemistry in selected brain regions. RESULTS At the pre-plaque stage, QPPs in TgF344-AD rats showed decreased activity of the basal forebrain (BFB) and the default mode-like network. Histological analyses revealed increased astrocyte abundance restricted to the BFB, in the absence of amyloid plaques, tauopathy, and alterations in a number of cholinergic, gaba-ergic, and glutamatergic synapses. During the early-plaque stage, when mild amyloid-beta (Aβ) accumulation was observed in the cortex and hippocampus, QPPs in the TgF344-AD rats normalized suggesting the activation of compensatory mechanisms during this early disease progression period. Interestingly, astrogliosis observed in the BFB at the pre-plaque stage was absent at the early-plaque stage. Moreover, altered excitatory/inhibitory balance was observed in cortical regions belonging to the default mode-like network. In wild-type rats, at both time points, peak activity in the BFB preceded peak activity in other brain regions-indicating its modulatory role during QPPs. However, this pattern was eliminated in TgF344-AD suggesting that alterations in BFB-directed neuromodulation have a pronounced impact in network function in AD. CONCLUSIONS This study demonstrates the value of rsfMRI and advanced network analysis methods to detect early alterations in BFB function in AD, which could aid early diagnosis and intervention in AD. Restoring the global synaptic transmission, possibly by modulating astrogliosis in the BFB, might be a promising therapeutic strategy to restore brain network function and delay the onset of symptoms in AD.
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Affiliation(s)
- Monica van den Berg
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Mohit H. Adhikari
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Marlies Verschuuren
- grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681Laboratory of Cell Biology and Histology, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,Antwerp Centre for Advanced Microscopy, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium
| | - Isabel Pintelon
- grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681Laboratory of Cell Biology and Histology, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,Antwerp Centre for Advanced Microscopy, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium
| | - Tamara Vasilkovska
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Johan Van Audekerke
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Stephan Missault
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Loran Heymans
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Peter Ponsaerts
- grid.5284.b0000 0001 0790 3681Laboratory of Experimental Hematology, Vaccine and Infectious Disease Institute (Vaxinfectio), University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium
| | - Winnok H. De Vos
- grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681Laboratory of Cell Biology and Histology, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,Antwerp Centre for Advanced Microscopy, Universiteitsplein 1, 2610 Wilrijk, Antwerp, Belgium
| | - Annemie Van der Linden
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
| | - Georgios A. Keliris
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium ,grid.511960.aInstitute of Computer Science, Foundation for Research & Technology - Hellas, Heraklion, Crete, Greece
| | - Marleen Verhoye
- grid.5284.b0000 0001 0790 3681Bio-Imaging Lab, University of Antwerp, Universiteitsplein 1 2610 Wilrijk, Antwerp, Belgium ,grid.5284.b0000 0001 0790 3681µNEURO Research Centre of Excellence, University of Antwerp, Antwerp, Belgium
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15
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Bernaud VE, Bulen HL, Peña VL, Koebele SV, Northup-Smith SN, Manzo AA, Valenzuela Sanchez M, Opachich Z, Ruhland AM, Bimonte-Nelson HA. Task-dependent learning and memory deficits in the TgF344-AD rat model of Alzheimer's disease: three key timepoints through middle-age in females. Sci Rep 2022; 12:14596. [PMID: 36028737 PMCID: PMC9418316 DOI: 10.1038/s41598-022-18415-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 08/10/2022] [Indexed: 11/11/2022] Open
Abstract
The TgF344 rat model of Alzheimer's disease (AD) provides a comprehensive neuropathology presentation, with age-dependent development of tau tangles, amyloid-beta (A[Formula: see text]) plaques, neuronal loss, and increased gliosis. The behavioral trajectory of this model, particularly relating to spatial learning and memory, has yet to be fully characterized. The current experiment evaluated spatial working and reference memory performance, as well as several physiological markers of health, at 3 key age points in female TgF344-AD rats: 6-months, 9-months, and 12-months. At 6 months of age, indications of working and reference memory impairments were observed in transgenic (Tg) rats on the water radial-arm maze, a complex task that requires working and reference memory simultaneously; at 12 months old, Tg impairments were observed for two working memory measures on this task. Notably, no impairments were observed at the 9-month timepoint on this maze. For the Morris maze, a measure of spatial reference memory, Tg rats demonstrated significant impairment relative to wildtype (WT) controls at all 3 age-points. Frontal cortex, entorhinal cortex, and dorsal hippocampus were evaluated for A[Formula: see text]1-42 expression via western blot in Tg rats only. Analyses of A[Formula: see text]1-42 expression revealed age-dependent increases in all 3 regions critical to spatial learning and memory. Measures of physiological health, including heart, uterine, and body weights, revealed unique age-specific outcomes for female Tg rats, with the 9-month timepoint identified as critical for further research within the trajectory of AD-like behavior, physiology, and pathology.
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Affiliation(s)
- Victoria E Bernaud
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Haidyn L Bulen
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Veronica L Peña
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Stephanie V Koebele
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Steven N Northup-Smith
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Alma A Manzo
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Maria Valenzuela Sanchez
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Zorana Opachich
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Ashley M Ruhland
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA
| | - Heather A Bimonte-Nelson
- Behavioral Neuroscience and Comparative Psychology Division, Department of Psychology, Arizona Alzheimer's Consortium, Arizona State University, 950 S. McAllister Ave., PO Box 871104, Tempe, AZ, 85287, USA.
- Arizona Alzheimer's Consortium, 4745 N 7th St, Phoenix, AZ, 85014, USA.
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Smith LA, Goodman AM, McMahon LL. Dentate Granule Cells Are Hyperexcitable in the TgF344-AD Rat Model of Alzheimer's Disease. Front Synaptic Neurosci 2022; 14:826601. [PMID: 35685246 PMCID: PMC9171068 DOI: 10.3389/fnsyn.2022.826601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 04/05/2022] [Indexed: 11/13/2022] Open
Abstract
The dentate gyrus is both a critical gatekeeper for hippocampal signal processing and one of the first brain regions to become dysfunctional in Alzheimer's disease (AD). Accordingly, the appropriate balance of excitation and inhibition through the dentate is a compelling target for mechanistic investigation and therapeutic intervention in early AD. Previously, we reported an increased long-term potentiation (LTP) magnitude at medial perforant path-dentate granule cell (MPP-DGC) synapses in slices from both male and acutely ovariectomized female TgF344-AD rats compared with wild type (Wt) as early as 6 months of age that is accompanied by an increase in steady-state postsynaptic depolarization during the high-frequency stimulation used to induce plasticity. Subsequently, we found that heightened function of β-adrenergic receptors (β-ARs) drives the increase in the LTP magnitude, but the increase in steady-state depolarization was only partially due to β-AR activation. As we previously reported no detectable difference in spine density or presynaptic release probability, we entertained the possibility that DGCs themselves might have modified passive or active membrane properties, which may contribute to the significant increase in charge transfer during high-frequency stimulation. Using brain slice electrophysiology from 6-month-old female rats acutely ovariectomized to eliminate variability due to fluctuating plasma estradiol, we found significant changes in passive membrane properties and active membrane properties leading to increased DGC excitability in TgF344-AD rats. Specifically, TgF344-AD DGCs have an increased input resistance and decreased rheobase, decreased sag, and increased action potential (AP) spike accommodation. Importantly, we found that for the same amount of depolarizing current injection, DGCs from TgF344-AD compared with Wt rats have a larger magnitude voltage response, which was accompanied by a decreased delay to fire the first action potential, indicating TgF344-AD DGCs membranes are more excitable. Taken together, DGCs in TgF344-AD rats are more excitable, which likely contributes to the heightened depolarization during high-frequency synaptic activation.
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Hernandez CM, Jackson NL, Hernandez AR, McMahon LL. Impairments in Fear Extinction Memory and Basolateral Amygdala Plasticity in the TgF344-AD Rat Model of Alzheimer's Disease Are Distinct from Nonpathological Aging. eNeuro 2022; 9:ENEURO.0181-22.2022. [PMID: 35998297 PMCID: PMC9239848 DOI: 10.1523/eneuro.0181-22.2022] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 05/11/2022] [Indexed: 12/15/2022] Open
Abstract
Fear-based disorders such as post-traumatic stress disorder (PTSD) steepen age-related cognitive decline and double the risk for developing Alzheimer's disease (AD). Because of the seemingly hyperactive properties of fear memories, PTSD symptoms can worsen with age. Perturbations in the synaptic circuitry supporting fear memory extinction are key neural substrates of PTSD. The basolateral amygdala (BLA) is a medial temporal lobe structure that is critical in the encoding, consolidation, and retrieval of fear memories. As little is known about fear extinction memory and BLA synaptic dysfunction within the context of aging and AD, the goal of this study was to investigate how fear extinction memory deficits and basal amygdaloid nucleus (BA) synaptic dysfunction differentially associate in nonpathologic aging and AD in the TgF344AD (TgAD) rat model of AD. Young, middle-aged, and older-aged WT and TgAD rats were trained on a delay fear conditioning and extinction procedure before ex vivo extracellular field potential recording experiments in the BA. Relative to young WT rats, long-term extinction memory was impaired, and in general, was associated with a hyperexcitable BA and impaired LTP in TgAD rats at all ages. In contrast, long-term extinction memory was impaired in aged WT rats and was associated with impaired LTP but not BA hyperexcitability. Interestingly, the middle-aged TgAD rats showed intact short-term extinction and BA LTP, which is suggestive of a compensatory mechanism, whereas differential neural recruitment in older-aged WT rats may have facilitated short-term extinction. As such, associations between fear extinction memory and amygdala deficits in nonpathologic aging and AD are dissociable.
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Affiliation(s)
- Caesar M Hernandez
- Department of Cellular, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, Alabama 35294-0006
- Evelyn F. McKnight Brain Institute, The University of Alabama at Birmingham, Birmingham, Alabama 35294-2182
| | - Nateka L Jackson
- Evelyn F. McKnight Brain Institute, The University of Alabama at Birmingham, Birmingham, Alabama 35294-2182
| | - Abbi R Hernandez
- Evelyn F. McKnight Brain Institute, The University of Alabama at Birmingham, Birmingham, Alabama 35294-2182
- Department of Medicine, Division of Gerontology, Geriatrics, and Palliative Care, The University of Alabama at Birmingham, Birmingham, Alabama 35294
| | - Lori L McMahon
- Department of Cellular, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, Alabama 35294-0006
- Evelyn F. McKnight Brain Institute, The University of Alabama at Birmingham, Birmingham, Alabama 35294-2182
- Nathan Shock Center of Excellence in the Basic Biology of Aging, The University of Alabama at Birmingham, Birmingham, Alabama 35294
- Integrative Center for Aging Research, The University of Alabama at Birmingham, Birmingham, Alabama 35294
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Fowler CF, Goerzen D, Devenyi GA, Madularu D, Chakravarty MM, Near J. OUP accepted manuscript. Brain Commun 2022; 4:fcac072. [PMID: 35434622 PMCID: PMC9007326 DOI: 10.1093/braincomms/fcac072] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/12/2022] [Accepted: 03/16/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Caitlin F. Fowler
- Department of Biological and Biomedical Engineering, McGill University, Duff Medical Building, Montreal, Canada H3A 2B4
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
- Correspondence to: Caitlin F. Fowler, CIC Pavilion Office GH-2113 Douglas Mental Health University Institute 6875 Boulevard LaSalle Montreal, Canada H4H 1R3 E-mail:
| | - Dana Goerzen
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
| | - Gabriel A. Devenyi
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
- Department of Psychiatry, McGill University, Montreal, Canada H3A 1A1
| | - Dan Madularu
- Centre for Translational NeuroImaging, Northeastern University, Boston, USA
| | - M. Mallar Chakravarty
- Department of Biological and Biomedical Engineering, McGill University, Duff Medical Building, Montreal, Canada H3A 2B4
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
- Department of Psychiatry, McGill University, Montreal, Canada H3A 1A1
| | - Jamie Near
- Department of Biological and Biomedical Engineering, McGill University, Duff Medical Building, Montreal, Canada H3A 2B4
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
- Department of Psychiatry, McGill University, Montreal, Canada H3A 1A1
- Physical Studies Research Platform, Sunnybrook Research Institute, Toronto, Canada M4N 3M5
- Department of Medical Biophysics, University of Toronto, Toronto, Canada M5G 1L7
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Proskauer Pena SL, Mallouppas K, Oliveira AMG, Zitricky F, Nataraj A, Jezek K. Early Spatial Memory Impairment in a Double Transgenic Model of Alzheimer's Disease TgF-344 AD. Brain Sci 2021; 11:brainsci11101300. [PMID: 34679365 PMCID: PMC8533693 DOI: 10.3390/brainsci11101300] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 09/20/2021] [Accepted: 09/28/2021] [Indexed: 11/16/2022] Open
Abstract
Before the course of Alzheimer’s disease fully manifests itself and largely impairs a patient’s cognitive abilities, its progression has already lasted for a considerable time without being noticed. In this project, we mapped the development of spatial orientation impairment in an active place avoidance task—a highly sensitive test for mild hippocampal damage. We tested vision, anxiety and spatial orientation performance at four age levels of 4, 6, 9, and 12 months across male and female TgF-344 AD rats carrying human genes for presenilin-1 and amyloid precursor protein. We found a progressive deterioration of spatial navigation in transgenic animals, beginning already at the age of 4 months, that fully developed at 6 months of age across both male and female groups, compared to their age-matched controls. In addition, we described the gradual vision impairment that was accentuated in females at the age of 12 months. These results indicate a rather early onset of cognitive impairment in the TgF-344 AD Alzheimer’s disease model, starting earlier than shown to date, and preceding the reported development of amyloid plaques.
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Goodman AM, Langner BM, Jackson N, Alex C, McMahon LL. Heightened Hippocampal β-Adrenergic Receptor Function Drives Synaptic Potentiation and Supports Learning and Memory in the TgF344-AD Rat Model during Prodromal Alzheimer's Disease. J Neurosci 2021; 41:5747-5761. [PMID: 33952633 PMCID: PMC8244969 DOI: 10.1523/jneurosci.0119-21.2021] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 02/23/2021] [Accepted: 04/28/2021] [Indexed: 01/27/2023] Open
Abstract
The central noradrenergic (NA) system is critical for the maintenance of attention, behavioral flexibility, spatial navigation, and learning and memory, those cognitive functions lost first in early Alzheimer's disease (AD). In fact, the locus coeruleus (LC), the sole source of norepinephrine (NE) for >90% of the brain, is the first site of pathologic tau accumulation in human AD with axon loss throughout forebrain, including hippocampus. The dentate gyrus is heavily innervated by LC-NA axons, where released NE acts on β-adrenergic receptors (ARs) at excitatory synapses from entorhinal cortex to facilitate long-term synaptic plasticity and memory formation. These synapses experience dysfunction in early AD before cognitive impairment. In the TgF344-AD rat model of AD, degeneration of LC-NA axons in hippocampus recapitulates human AD, providing a preclinical model to investigate synaptic and behavioral consequences. Using immunohistochemistry, Western blot analysis, and brain slice electrophysiology in 6- to 9-month-old wild-type and TgF344-AD rats, we discovered that the loss of LC-NA axons coincides with the heightened β-AR function at medial perforant path-dentate granule cell synapses that is responsible for the increase in LTP magnitude at these synapses. Furthermore, novel object recognition is facilitated in TgF344-AD rats that requires β-ARs, and pharmacological blockade of β-ARs unmasks a deficit in extinction learning only in TgF344-AD rats, indicating a greater reliance on β-ARs in both behaviors. Thus, a compensatory increase in β-AR function during prodromal AD in TgF344-AD rats heightens synaptic plasticity and preserves some forms of learning and memory.SIGNIFICANCE STATEMENT The locus coeruleus (LC), a brain region located in the brainstem which is responsible for attention and arousal, is damaged first by Alzheimer's disease (AD) pathology. The LC sends axons to hippocampus where released norepinephrine (NE) modulates synaptic function required for learning and memory. How degeneration of LC axons and loss of NE in hippocampus in early AD impacts synaptic function and learning and memory is not well understood despite the importance of LC in cognitive function. We used a transgenic AD rat model with LC axon degeneration mimicking human AD and found that heightened function of β-adrenergic receptors in the dentate gyrus increased synaptic plasticity and preserved learning and memory in early stages of the disease.
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Affiliation(s)
- Anthoni M Goodman
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0006
| | - Bethany M Langner
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0006
| | - Nateka Jackson
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0006
| | - Capri Alex
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0006
| | - Lori L McMahon
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama 35294-0006
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21
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Subhadeep D, Srikumar BN, Shankaranarayana Rao BS, Kutty BM. Exposure to Short Photoperiod Regime Restores Spatial Cognition in Ventral Subicular Lesioned Rats: Potential Role of Hippocampal Plasticity, Glucocorticoid Receptors, and Neurogenesis. Mol Neurobiol 2021; 58:4437-4459. [PMID: 34024004 DOI: 10.1007/s12035-021-02409-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 04/27/2021] [Indexed: 12/29/2022]
Abstract
Ambient light influences our mood, behavior, and cognition. Phototherapy has been considered as an effective non-pharmacological intervention strategy in the restoration of cognitive functions following central nervous system insults. However, the cellular and molecular underpinnings of phototherapy-mediated functional recovery are yet to be studied. The present study examines the effectiveness of short photoperiod regime (SPR; 6:18-h light:dark cycle) in restoring the cognitive functions in ventral subicular lesioned rats. Bilateral ventral subicular lesion (VSL) resulted in significant impairment of spatial navigational abilities when tested in the Morris water maze (MWM) task. Further, VSL resulted in reduced expression of glucocorticoid receptors (GRs) and activity-regulated cytoskeletal (Arc) protein and suppression of neurogenesis in the hippocampus. VSL also suppressed the magnitude of long-term potentiation (LTP) in the hippocampal Schaffer collateral-CA1 synapses. However, exposure to SPR for 21 days showed significant restoration of spatial performance in the MWM task as the ventral subicular lesioned rats could deploy higher cognitive allocentric navigational strategies to reach the hidden platform. Further, SPR resulted in enhanced expression of hippocampal GR and Arc protein and neurogenesis but not hippocampal LTP suggestive of appropriate need-based SPR intervention. In conclusion, the study demonstrates the effectiveness of SPR in establishing functional recovery as well as the possible molecular and cellular basis of cognitive recovery in a rat model of neurodegeneration. Such studies provide a framework in understanding the efficacy of non-pharmacological strategies in establishing functional recovery in neurodegenerative conditions.
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Affiliation(s)
- Duttagupta Subhadeep
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences (NIMHANS), Hosur Road, Bengaluru, 560029, India
| | - B N Srikumar
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences (NIMHANS), Hosur Road, Bengaluru, 560029, India
| | - B S Shankaranarayana Rao
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences (NIMHANS), Hosur Road, Bengaluru, 560029, India
| | - Bindu M Kutty
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences (NIMHANS), Hosur Road, Bengaluru, 560029, India.
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22
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Pentkowski NS, Rogge-Obando KK, Donaldson TN, Bouquin SJ, Clark BJ. Anxiety and Alzheimer's disease: Behavioral analysis and neural basis in rodent models of Alzheimer's-related neuropathology. Neurosci Biobehav Rev 2021; 127:647-658. [PMID: 33979573 DOI: 10.1016/j.neubiorev.2021.05.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 04/28/2021] [Accepted: 05/05/2021] [Indexed: 11/29/2022]
Abstract
Alzheimer's disease (AD) pathology is commonly associated with cognitive decline but is also composed of neuropsychiatric symptoms including psychological distress and alterations in mood, including anxiety and depression. Emotional dysfunction in AD is frequently modeled using tests of anxiety-like behavior in transgenic rodents. These tests often include the elevated plus-maze, light/dark test and open field test. In this review, we describe prototypical behavioral paradigms used to examine emotional dysfunction in transgenic models of AD, specifically anxiety-like behavior. Next, we summarize the results of studies examining anxiety-like behavior in transgenic rodents, noting that the behavioral outcomes using these paradigms have produced inconsistent results. We suggest that future research will benefit from using a battery of tests to examine emotional behavior in transgenic AD models. We conclude by discussing putative, overlapping neurobiological mechanisms underlying AD-related neuropathology, stress and anxiety-like behavior reported in AD models.
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Affiliation(s)
- Nathan S Pentkowski
- Department of Psychology, University of New Mexico, Albuquerque, NM, 87109, Mexico.
| | | | - Tia N Donaldson
- Department of Psychology, University of New Mexico, Albuquerque, NM, 87109, Mexico
| | - Samuel J Bouquin
- Department of Psychology, University of New Mexico, Albuquerque, NM, 87109, Mexico
| | - Benjamin J Clark
- Department of Psychology, University of New Mexico, Albuquerque, NM, 87109, Mexico.
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23
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Chaney AM, Lopez-Picon FR, Serrière S, Wang R, Bochicchio D, Webb SD, Vandesquille M, Harte MK, Georgiadou C, Lawrence C, Busson J, Vercouillie J, Tauber C, Buron F, Routier S, Reekie T, Snellman A, Kassiou M, Rokka J, Davies KE, Rinne JO, Salih DA, Edwards FA, Orton LD, Williams SR, Chalon S, Boutin H. Prodromal neuroinflammatory, cholinergic and metabolite dysfunction detected by PET and MRS in the TgF344-AD transgenic rat model of AD: a collaborative multi-modal study. Am J Cancer Res 2021; 11:6644-6667. [PMID: 34093845 PMCID: PMC8171096 DOI: 10.7150/thno.56059] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 02/15/2021] [Indexed: 12/25/2022] Open
Abstract
Mouse models of Alzheimer's disease (AD) are valuable but do not fully recapitulate human AD pathology, such as spontaneous Tau fibril accumulation and neuronal loss, necessitating the development of new AD models. The transgenic (TG) TgF344-AD rat has been reported to develop age-dependent AD features including neuronal loss and neurofibrillary tangles, despite only expressing APP and PSEN1 mutations, suggesting an improved modelling of AD hallmarks. Alterations in neuronal networks as well as learning performance and cognition tasks have been reported in this model, but none have combined a longitudinal, multimodal approach across multiple centres, which mimics the approaches commonly taken in clinical studies. We therefore aimed to further characterise the progression of AD-like pathology and cognition in the TgF344-AD rat from young-adults (6 months (m)) to mid- (12 m) and advanced-stage (18 m, 25 m) of the disease. Methods: TgF344-AD rats and wild-type (WT) littermates were imaged at 6 m, 12 m and 18 m with [18F]DPA-714 (TSPO, neuroinflammation), [18F]Florbetaben (Aβ) and [18F]ASEM (α7-nicotinic acetylcholine receptor) and with magnetic resonance spectroscopy (MRS) and with (S)-[18F]THK5117 (Tau) at 15 and 25 m. Behaviour tests were also performed at 6 m, 12 m and 18 m. Immunohistochemistry (CD11b, GFAP, Aβ, NeuN, NeuroChrom) and Tau (S)-[18F]THK5117 autoradiography, immunohistochemistry and Western blot were also performed. Results: [18F]DPA-714 positron emission tomography (PET) showed an increase in neuroinflammation in TG vs wildtype animals from 12 m in the hippocampus (+11%), and at the advanced-stage AD in the hippocampus (+12%), the thalamus (+11%) and frontal cortex (+14%). This finding coincided with strong increases in brain microgliosis (CD11b) and astrogliosis (GFAP) at these time-points as assessed by immunohistochemistry. In vivo [18F]ASEM PET revealed an age-dependent increase uptake in the striatum and pallidum/nucleus basalis of Meynert in WT only, similar to that observed with this tracer in humans, resulting in TG being significantly lower than WT by 18 m. In vivo [18F]Florbetaben PET scanning detected Aβ accumulation at 18 m, and (S)-[18F]THK5117 PET revealed subsequent Tau accumulation at 25m in hippocampal and cortical regions. Aβ plaques were low but detectable by immunohistochemistry from 6 m, increasing further at 12 and 18 m with Tau-positive neurons adjacent to Aβ plaques at 18 m. NeuroChrom (a pan neuronal marker) immunohistochemistry revealed a loss of neuronal staining at the Aβ plaques locations, while NeuN labelling revealed an age-dependent decrease in hippocampal neuron number in both genotypes. Behavioural assessment using the novel object recognition task revealed that both WT & TgF344-AD animals discriminated the novel from familiar object at 3 m and 6 m of age. However, low levels of exploration observed in both genotypes at later time-points resulted in neither genotype successfully completing the task. Deficits in social interaction were only observed at 3 m in the TgF344-AD animals. By in vivo MRS, we showed a decrease in neuronal marker N-acetyl-aspartate in the hippocampus at 18 m (-18% vs age-matched WT, and -31% vs 6 m TG) and increased Taurine in the cortex of TG (+35% vs age-matched WT, and +55% vs 6 m TG). Conclusions: This multi-centre multi-modal study demonstrates, for the first time, alterations in brain metabolites, cholinergic receptors and neuroinflammation in vivo in this model, validated by robust ex vivo approaches. Our data confirm that, unlike mouse models, the TgF344-AD express Tau pathology that can be detected via PET, albeit later than by ex vivo techniques, and is a useful model to assess and longitudinally monitor early neurotransmission dysfunction and neuroinflammation in AD.
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Potential of Caffeine in Alzheimer's Disease-A Review of Experimental Studies. Nutrients 2021; 13:nu13020537. [PMID: 33562156 PMCID: PMC7915779 DOI: 10.3390/nu13020537] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/29/2021] [Accepted: 02/02/2021] [Indexed: 02/08/2023] Open
Abstract
Alzheimer's disease (AD) is the most common type of dementia leading to progressive memory loss and cognitive impairment. Considering that pharmacological treatment options for AD are few and not satisfactory, increasing attention is being paid to dietary components that may affect the development of the disease. Such a dietary component may be caffeine contained in coffee, tea or energy drinks. Although epidemiological data suggest that caffeine intake may counteract the development of cognitive impairment, results of those studies are not conclusive. The aim of the present study is to review the existing experimental studies on the efficacy of caffeine against AD and AD-related cognitive impairment, focusing on the proposed protective mechanisms of action. In conclusion, the reports of studies on experimental AD models generally supported the notion that caffeine may exert some beneficial effects in AD. However, further studies are necessary to elucidate the role of caffeine in the effects of its sources on cognition and possibly AD risk.
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Wan J, Shen CM, Wang Y, Wu QZ, Wang YL, Liu Q, Sun YM, Cao JP, Wu YQ. Repeated exposure to propofol in the neonatal period impairs hippocampal synaptic plasticity and the recognition function of rats in adulthood. Brain Res Bull 2021; 169:63-72. [PMID: 33450329 DOI: 10.1016/j.brainresbull.2021.01.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 12/30/2020] [Accepted: 01/07/2021] [Indexed: 12/09/2022]
Abstract
Anesthesia of neonates with propofol induces persistent behavioral abnormalities in adulthood. Although propofol-triggered apoptosis of neurons in the developing brain may contribute to the development of cognitive deficits, the mechanism of neurotoxicity induced by neonatal exposure to propofol remains unclear. In this study, the effects of neonatal propofol anesthesia on synaptic plasticity and neurocognitive function were investigated. Postnatal day 7 (PND-7) Sprague-Dawley rats were intraperitoneally injected with fat emulsion or 20, 40 or 60 mg/kg propofol for three consecutive days. The expression of brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB) and postsynaptic density protein 95 (PSD-95) in the rat hippocampus at PND-10 and PND-12 was measured by Western blotting. The number of dendritic branches, total dendritic length and dendritic spine density were observed by Golgi-Cox staining 24 h and 72 h after the last propofol administration. Long-term potentiation (LTP) was measured electrophysiologically in hippocampus of PND-60 rats to evaluate the synaptic function. The learning and memory abilities of rats were evaluated by Morris water maze (MWM) experiments, Novel object recognition test (NORT) and Object location test (OLT) at PND-60. Our results showed that neonatal exposure to propofol significantly inhibited the expression of BDNF, TrkB and PSD-95 in the rat hippocampus. The number of dendritic branches, total dendritic length and dendritic spine density of neurons in the rat hippocampus were markedly reduced after neonatal propofol anesthesia. LTP was significantly diminished in hippocampus of PND-60 rats after repeated exposure to propofol in the neonatal period. Morris water maze experiments showed that repeated neonatal exposure to propofol significantly prolonged the escape latency and decreased the time spent in the target quadrant and the number of platform crossings. NORT and OLT showed that repeated neonatal exposure to propofol markedly reduced the Investigation Time for novel object or location. All of the results above indicate that repeated exposure to propofol in the neonatal period can impair hippocampal synaptic plasticity and the recognition function of rats in adulthood.
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Affiliation(s)
- Jie Wan
- School of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China
| | - Chu-Meng Shen
- School of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China
| | - Yu Wang
- School of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China
| | - Qing-Zi Wu
- School of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China
| | - Yi-Lei Wang
- School of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China
| | - Qiang Liu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China
| | - Yi-Man Sun
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China
| | - Jun-Ping Cao
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China.
| | - Yu-Qing Wu
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, PR China.
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26
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Ramani M, Miller K, Ambalavanan N, McMahon LL. Increased Excitability and Heightened Magnitude of Long-Term Potentiation at Hippocampal CA3-CA1 Synapses in a Mouse Model of Neonatal Hyperoxia Exposure. Front Synaptic Neurosci 2021; 12:609903. [PMID: 33488380 PMCID: PMC7815524 DOI: 10.3389/fnsyn.2020.609903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/10/2020] [Indexed: 11/26/2022] Open
Abstract
Preterm infants exposed to supraphysiological oxygen (hyperoxia) during the neonatal period have hippocampal atrophy and cognitive dysfunction later in childhood and as adolescents. Previously, we reported that 14-week-old adult mice exposed to hyperoxia as newborns had spatial memory deficits and hippocampal shrinkage, findings that mirror those of human adolescents who were born preterm. The area CA1 region of the hippocampus that is crucial for spatial learning and memory is highly vulnerable to oxidative stress. In this study, we investigated the long-term impact of neonatal hyperoxia exposure on hippocampal CA3-CA1 synaptic function. Male and female C57BL/6J mouse pups were continuously exposed to either 85% normobaric oxygen or air between postnatal days 2-14. Hippocampal slice electrophysiology at CA3-CA1 synapses was then performed at 14 weeks of age. We observed that hyperoxia exposed mice have heightened strength of basal synaptic transmission measured in input-output curves, increased fiber volley amplitude indicating increased axonal excitability, and heightened LTP magnitude at CA3-CA1 synapses, likely a consequence of increased postsynaptic depolarization during tetanus. These data demonstrate that supraphysiological oxygen exposure during the critical neonatal developmental period leads to pathologically heightened CA3-CA1 synaptic function during early adulthood which may contribute to hippocampal shrinkage and learning and memory deficits we previously reported. Furthermore, these results will help shed light on the consequences of hyperoxia exposure on the development of hippocampal synaptic circuit abnormalities that could be contributing to cognitive deficits in children born preterm.
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Affiliation(s)
- Manimaran Ramani
- Department of Pediatrics, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Kiara Miller
- Department of Pediatrics, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Namasivayam Ambalavanan
- Department of Pediatrics, The University of Alabama at Birmingham, Birmingham, AL, United States
- Departments of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL, United States
| | - Lori L. McMahon
- Departments of Cell, Developmental, and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL, United States
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Kolinko Y, Marsalova L, Proskauer Pena S, Kralickova M, Mouton PR. Stereological Changes in Microvascular Parameters in Hippocampus of a Transgenic Rat Model of Alzheimer's Disease. J Alzheimers Dis 2021; 84:249-260. [PMID: 34542078 PMCID: PMC8609684 DOI: 10.3233/jad-210738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2021] [Indexed: 11/15/2022]
Abstract
BACKGROUND Microcirculatory factors play an important role in amyloid-β (Aβ)-related neuropathology in Alzheimer's disease (AD). Transgenic (Tg) rat models of mutant Aβ deposition can enhance our understanding of this microvascular pathology. OBJECTIVE Here we report stereology-based quantification and comparisons (between- and within-group) of microvessel length and number and associated parameters in hippocampal subregions in Tg model of AD in Fischer 344 rats and non-Tg littermates. METHODS Systematic-random samples of tissue sections were processed and laminin immunostained to visualize microvessels through the entire hippocampus in Tg and non-Tg rats. A computer-assisted stereology system was used to quantify microvessel parameters including total number, total length, and associated densities in dentate gyrus (DG) and cornu ammonis (CA) subregions. RESULTS Thin hair-like capillaries are common near Aβ plaques in hippocampal subregions of Tg rats. There are a 53% significant increase in average length per capillary across entire hippocampus (p≤0.04) in Tg compared to non-Tg rats; 49% reduction in capillary length in DG (p≤0.02); and, higher microvessel density in principal cell layers (p≤0.03). Furthermore, within-group comparisons confirm Tg but not non-Tg rats have significant increase in number density (p≤0.01) and potential diffusion distance (p≤0.04) of microvessels in principal cell layers of hippocampal subregions. CONCLUSION We show the Tg deposition of human Aβ mutations in rats disrupts the wild-type microanatomy of hippocampal microvessels. Stereology-based microvascular parameters could promote the development of novel strategies for protection and the therapeutic management of AD.
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Affiliation(s)
- Yaroslav Kolinko
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
- Department of Histology and Embryology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
| | - Lucie Marsalova
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
- Department of Histology and Embryology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
| | | | - Milena Kralickova
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
- Department of Histology and Embryology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
| | - Peter R. Mouton
- SRC Biosciences, Tampa, FL, USA
- University of South Florida, Tampa, FL, USA
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Zhao L, Liu JW, Kan BH, Shi HY, Yang LP, Liu XY. Acupuncture accelerates neural regeneration and synaptophysin production after neural stem cells transplantation in mice. World J Stem Cells 2020; 12:1576-1590. [PMID: 33505601 PMCID: PMC7789117 DOI: 10.4252/wjsc.v12.i12.1576] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 09/23/2020] [Accepted: 10/13/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Synaptophysin plays a key role in synaptic development and plasticity of neurons and is closely related to the cognitive process of Alzheimer’s disease (AD) patients. Exogenous neural stem cells (NSCs) improve the damaged nerve function. The effects of Sanjiao acupuncture on cognitive impairment may be related to the regulation of the NSC microenvironment.
AIM To explore the anti-dementia mechanism of acupuncture by regulating the NSC microenvironment.
METHODS NSCs were isolated from pregnant senescence-accelerated mouse resistant 1 (SAMR1) mice, labeled with BrdU, and injected into the hippocampus of senescence-accelerated mouse prone 8 (SAMP8) mice. Eight-month-old senescence-accelerated mice (SAM) were randomly divided into six groups: SAMR1 (RC), SAMP8 (PC), sham transplantation (PS), NSC transplantation (PT), NSC transplantation with acupuncture (PTA), and NSC transplantation with non-acupoint acupuncture (PTN). Morris water maze test was used to study the learning and memory ability of mice after NSC transplantation. Hematoxylin-eosin staining and immunofluorescence were used to observe the his-topathological changes and NSC proliferation in mice. A co-culture model of hippocampal slices and NSCs was established in vitro, and the synaptophysin expression in the hippocampal microenvironment of mice was observed by flow cytometry after acupuncture treatment.
RESULTS Morris water maze test showed significant cognitive impairment of learning and memory in 8-mo-old SAMP8, which improved in all the NSC transplantation groups. The behavioral change in the PTA group was stronger than those in the other two groups (P < 0.05). Histopathologically, the hippocampal structure was clear, the cell arrangement was dense and orderly, and the necrosis of cells in CA1 and CA3 areas was significantly reduced in the PTA group when compared with the PC group. The BrdU-positive proliferating cells were found in NSC hippocampal transplantation groups, and the number increased significantly in the PTA group than in the PT and PTN groups (P < 0.05). Flow cytometry showed that after co-culture of NSCs with hippocampal slices in vitro, the synaptophysin expression in the PC group decreased in comparison to the RC group, that in PT, PTA, and PTN groups increased as compared to the PC group, and that in the PTA group increased significantly as compared to the PTN group with acupoint-related specificity (P < 0.05).
CONCLUSION Acupuncture may promote nerve regeneration and synaptogenesis in SAMP8 mice by regulating the microenvironment of NSC transplantation to improve the nerve activity and promote the recovery of AD-damaged cells.
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Affiliation(s)
- Lan Zhao
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin 300381, China
- Tianjin Key Laboratory of Acupuncture and Moxibustion, Tianjin 300381, China
- National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin 300381, China
| | - Jian-Wei Liu
- Tianjin University of Traditional Chinese Medicine, Tianjin 300193, China
| | - Bo-Hong Kan
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin 300381, China
- Tianjin Key Laboratory of Acupuncture and Moxibustion, Tianjin 300381, China
- National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin 300381, China
| | - Hui-Yan Shi
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin 300381, China
- Tianjin Key Laboratory of Acupuncture and Moxibustion, Tianjin 300381, China
- National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin 300381, China
| | - Lin-Po Yang
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin 300381, China
| | - Xin-Yu Liu
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin 300381, China
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Morrone CD, Bazzigaluppi P, Beckett TL, Hill ME, Koletar MM, Stefanovic B, McLaurin J. Regional differences in Alzheimer's disease pathology confound behavioural rescue after amyloid-β attenuation. Brain 2020; 143:359-373. [PMID: 31782760 PMCID: PMC6935751 DOI: 10.1093/brain/awz371] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 09/16/2019] [Accepted: 10/01/2019] [Indexed: 12/31/2022] Open
Abstract
Failure of Alzheimer’s disease clinical trials to improve or stabilize cognition has led to the need for a better understanding of the driving forces behind cognitive decline in the presence of active disease processes. To dissect contributions of individual pathologies to cognitive function, we used the TgF344-AD rat model, which recapitulates the salient hallmarks of Alzheimer’s disease pathology observed in patient populations (amyloid, tau inclusions, frank neuronal loss, and cognitive deficits). scyllo-Inositol treatment attenuated amyloid-β peptide in disease-bearing TgF344-AD rats, which rescued pattern separation in the novel object recognition task and executive function in the reversal learning phase of the Barnes maze. Interestingly, neither activities of daily living in the burrowing task nor spatial memory in the Barnes maze were rescued by attenuating amyloid-β peptide. To understand the pathological correlates leading to behavioural rescue, we examined the neuropathology and in vivo electrophysiological signature of the hippocampus. Amyloid-β peptide attenuation reduced hippocampal tau pathology and rescued adult hippocampal neurogenesis and neuronal function, via improvements in cross-frequency coupling between theta and gamma bands. To investigate mechanisms underlying the persistence of spatial memory deficits, we next examined neuropathology in the entorhinal cortex, a region whose input to the hippocampus is required for spatial memory. Reduction of amyloid-β peptide in the entorhinal cortex had no effect on entorhinal tau pathology or entorhinal-hippocampal neuronal network dysfunction, as measured by an impairment in hippocampal response to entorhinal stimulation. Thus, rescue or not of cognitive function is dependent on regional differences of amyloid-β, tau and neuronal network dysfunction, demonstrating the importance of staging disease in patients prior to enrolment in clinical trials. These results further emphasize the need for combination therapeutic approaches across disease progression.
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Affiliation(s)
- Christopher D Morrone
- Sunnybrook Research Institute, Biological Sciences, 2075 Bayview Ave, Toronto, ON, Canada.,University of Toronto, Faculty of Medicine, Department of Laboratory Medicine and Pathobiology, 1 King's College Cir, Toronto, ON, Canada
| | - Paolo Bazzigaluppi
- Sunnybrook Research Institute, Physical Sciences, 2075 Bayview Ave, Toronto, ON, Canada
| | - Tina L Beckett
- Sunnybrook Research Institute, Biological Sciences, 2075 Bayview Ave, Toronto, ON, Canada
| | - Mary E Hill
- Sunnybrook Research Institute, Biological Sciences, 2075 Bayview Ave, Toronto, ON, Canada
| | - Margaret M Koletar
- Sunnybrook Research Institute, Physical Sciences, 2075 Bayview Ave, Toronto, ON, Canada
| | - Bojana Stefanovic
- Sunnybrook Research Institute, Physical Sciences, 2075 Bayview Ave, Toronto, ON, Canada.,University of Toronto, Faculty of Medicine, Department of Medical Biophysics, 101 College St Suite 15-701, Toronto, ON, Canada
| | - JoAnne McLaurin
- Sunnybrook Research Institute, Biological Sciences, 2075 Bayview Ave, Toronto, ON, Canada.,University of Toronto, Faculty of Medicine, Department of Laboratory Medicine and Pathobiology, 1 King's College Cir, Toronto, ON, Canada
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Denver P, D’Adamo H, Hu S, Zuo X, Zhu C, Okuma C, Kim P, Castro D, Jones MR, Leal C, Mekkittikul M, Ghadishah E, Teter B, Vinters HV, Cole GM, Frautschy SA. A Novel Model of Mixed Vascular Dementia Incorporating Hypertension in a Rat Model of Alzheimer's Disease. Front Physiol 2019; 10:1269. [PMID: 31708792 PMCID: PMC6821690 DOI: 10.3389/fphys.2019.01269] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 09/19/2019] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) and mixed dementia (MxD) comprise the majority of dementia cases in the growing global aging population. MxD describes the coexistence of AD pathology with vascular pathology, including cerebral small vessel disease (SVD). Cardiovascular disease increases risk for AD and MxD, but mechanistic synergisms between the coexisting pathologies affecting dementia risk, progression and the ultimate clinical manifestations remain elusive. To explore the additive or synergistic interactions between AD and chronic hypertension, we developed a rat model of MxD, produced by breeding APPswe/PS1ΔE9 transgenes into the stroke-prone spontaneously hypertensive rat (SHRSP) background, resulting in the SHRSP/FAD model and three control groups (FAD, SHRSP and non-hypertensive WKY rats, n = 8-11, both sexes, 16-18 months of age). After behavioral testing, rats were euthanized, and tissue assessed for vascular, neuroinflammatory and AD pathology. Hypertension was preserved in the SHRSP/FAD cross. Results showed that SHRSP increased FAD-dependent neuroinflammation (microglia and astrocytes) and tau pathology, but plaque pathology changes were subtle, including fewer plaques with compact cores and slightly reduced plaque burden. Evidence for vascular pathology included a change in the distribution of astrocytic end-foot protein aquaporin-4, normally distributed in microvessels, but in SHRSP/FAD rats largely dissociated from vessels, appearing disorganized or redistributed into neuropil. Other evidence of SVD-like pathology included increased collagen IV staining in cerebral vessels and PECAM1 levels. We identified a plasma biomarker in SHRSP/FAD rats that was the only group to show increased Aqp-4 in plasma exosomes. Evidence of neuron damage in SHRSP/FAD rats included increased caspase-cleaved actin, loss of myelin and reduced calbindin staining in neurons. Further, there were mitochondrial deficits specific to SHRSP/FAD, notably the loss of complex II, accompanying FAD-dependent loss of mitochondrial complex I. Cognitive deficits exhibited by FAD rats were not exacerbated by the introduction of the SHRSP phenotype, nor was the hyperactivity phenotype associated with SHRSP altered by the FAD transgene. This novel rat model of MxD, encompassing an amyloidogenic transgene with a hypertensive phenotype, exhibits several features associated with human vascular or "mixed" dementia and may be a useful tool in delineating the pathophysiology of MxD and development of therapeutics.
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Affiliation(s)
- Paul Denver
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Heather D’Adamo
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Shuxin Hu
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Xiaohong Zuo
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Cansheng Zhu
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Chihiro Okuma
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Peter Kim
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Daniel Castro
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Mychica R. Jones
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Carmen Leal
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Marisa Mekkittikul
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Elham Ghadishah
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Bruce Teter
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Harry V. Vinters
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
| | - Gregory Michael Cole
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
| | - Sally A. Frautschy
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Geriatric Research Education and Clinical Center, Greater Los Angeles Veterans Affairs Healthcare System, Los Angeles, CA, United States
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Tudela R, Muñoz-Moreno E, Sala-Llonch R, López-Gil X, Soria G. Resting State Networks in the TgF344-AD Rat Model of Alzheimer's Disease Are Altered From Early Stages. Front Aging Neurosci 2019; 11:213. [PMID: 31440158 PMCID: PMC6694297 DOI: 10.3389/fnagi.2019.00213] [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] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 07/26/2019] [Indexed: 12/12/2022] Open
Abstract
A better and non-invasive characterization of the preclinical phases of Alzheimer's disease (AD) is important to advance its diagnosis and obtain more effective benefits from potential treatments. The TgF344-AD rat model has been well characterized and shows molecular, behavioral and brain connectivity alterations that resemble the silent period of the pathology. Our aim was to longitudinally investigate functional brain connectivity in established resting-state networks (RSNs) obtained by independent component analysis (ICA) in a cohort of TgF344-AD and control rats every 3 months, from 5 to 18 months of age, to cover different stages of the disease. Before each acquisition, working memory performance was evaluated by the delayed non match-to-sample (DNMS) task. Differences in the temporal evolution were observed between groups in the amplitude and shape of the somatosensorial and sensorimotor networks but not in the whole default mode network (DMN). Subsequent high dimensional ICA analysis showed early alterations in the anterior DMN subnetwork activity of TgF344-AD rats compared to controls. Performance of DNMS task was positively correlated with somatosensorial network at 5 months of age in the wild-type (WT) animals but not in the Tg-F344 rats. At different time points, DMN showed negative correlation with cognitive performance in the control group while in the transgenic group the correlation was positive. In addition, behavioral differences observed at 5 months of age correlated with alterations in the posterior DMN subnetwork. We have demonstrated that functional connectivity using ICA represents a useful biomarker also in animal models of AD such as the TgF344AD rats, as it allows the identification of alterations associated with the progression of the disease, detecting differences in specific networks even at very early stages.
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Affiliation(s)
- Raúl Tudela
- Consorcio Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Group of Biomedical Imaging, University of Barcelona, Barcelona, Spain
| | - Emma Muñoz-Moreno
- Experimental 7T MRI Unit, Institut d’Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
| | - Roser Sala-Llonch
- Department of Biomedicine, Faculty of Medicine, University of Barcelona, Barcelona, Spain
| | - Xavier López-Gil
- Experimental 7T MRI Unit, Institut d’Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
| | - Guadalupe Soria
- Consorcio Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Group of Biomedical Imaging, University of Barcelona, Barcelona, Spain
- Experimental 7T MRI Unit, Institut d’Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
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32
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Early functional connectivity deficits and progressive microstructural alterations in the TgF344-AD rat model of Alzheimer’s Disease: A longitudinal MRI study. Neurobiol Dis 2019; 124:93-107. [DOI: 10.1016/j.nbd.2018.11.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 11/05/2018] [Accepted: 11/12/2018] [Indexed: 01/05/2023] Open
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33
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Anckaerts C, Blockx I, Summer P, Michael J, Hamaide J, Kreutzer C, Boutin H, Couillard-Després S, Verhoye M, Van der Linden A. Early functional connectivity deficits and progressive microstructural alterations in the TgF344-AD rat model of Alzheimer’s Disease: A longitudinal MRI study. Neurobiol Dis 2019. [DOI: 10.1016/j.nbd.2018.11.010 and 21=21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Progressive impairment of directional and spatially precise trajectories by TgF344-Alzheimer's disease rats in the Morris Water Task. Sci Rep 2018; 8:16153. [PMID: 30385825 PMCID: PMC6212523 DOI: 10.1038/s41598-018-34368-w] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 10/10/2018] [Indexed: 12/12/2022] Open
Abstract
Spatial navigation is impaired in early stages of Alzheimer’s disease, and may be a defining behavioral marker of preclinical AD. A new rat model (TgF344-AD) of AD overcomes many limitations of other rodent models, though spatial navigation has not been comprehensively assessed. Using the hidden and cued platform variants of the Morris water task, a longitudinal assessment of spatial navigation was conducted on TgF344-AD (n = 16) and Fischer 344 (n = 12) male and female rats at three age ranges: 4 to 5 months, 7 to 8, and 10 to 11 months of age. TgF344-AD rats exhibited largely intact navigation at 4–5 months, with deficits in the hidden platform task emerging at 7–8 months and becoming significantly pronounced at 10–11 months of age. In general, TgF344-AD rats displayed less accurate swim trajectories to the platform and searched a wider area around the platform region compared to wildtype rats. Impaired navigation occurred in the absence of deficits in acquiring the procedural task demands or navigation to the cued platform location. Together, the results indicate that TgF344-AD rats exhibit comparable navigational deficits to those found in individuals with preclinical-AD.
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Widman AJ, Stewart AE, Erb EM, Gardner E, McMahon LL. Intravascular Ketamine Increases Theta-Burst but Not High Frequency Tetanus Induced LTP at CA3-CA1 Synapses Within Three Hours and Devoid of an Increase in Spine Density. Front Synaptic Neurosci 2018; 10:8. [PMID: 29899695 PMCID: PMC5989646 DOI: 10.3389/fnsyn.2018.00008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 04/30/2018] [Indexed: 12/17/2022] Open
Abstract
In the past 20 years, ketamine has become a promising treatment for Major Depressive Disorder (MDD) due to its rapid and sustain antidepressant effects in patients. A single ketamine treatment causes improvement in depressive symptoms within hours and can last weeks, long after it is eliminated. Previous studies have demonstrated increased synaptic plasticity at CA3-CA1 synapses in hippocampus (HPC) 24 h post ketamine treatment suggesting increased activity-dependent hippocampal function may underlie the antidepressant effects of ketamine. If true, these changes should also occur within hours of treatment, a time when symptoms are first alleviated in patients. To determine if augmented synaptic plasticity is observed at an earlier time point, we measured theta-burst and high frequency tetanus induced long-term potentiation (LTP) at CA3-CA1 synapses 3 h following intravenous (IV) ketamine administration. Additionally, we measured basal hippocampal function and spine density to investigate whether connectivity was increased with ketamine treatment. We report that theta-burst but not high frequency tetanus induced LTP is significantly increased 3 h after in vivo ketamine with no changes in basal synaptic function or morphology. Our finding supports increased activity-dependent hippocampal function underlying the antidepressant effects of ketamine as it occurs at a time point that correlates with initial improvements of depressive symptoms in patients.
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Affiliation(s)
- Allie J Widman
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Amy E Stewart
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Elise M Erb
- Department of Criminal Justice, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Elizabeth Gardner
- Department of Criminal Justice, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Lori L McMahon
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States
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