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Joy MSH, Nall DL, Emon B, Lee KY, Barishman A, Ahmed M, Rahman S, Selvin PR, Saif MTA. Synapses without tension fail to fire in an in vitro network of hippocampal neurons. Proc Natl Acad Sci U S A 2023; 120:e2311995120. [PMID: 38113266 PMCID: PMC10756289 DOI: 10.1073/pnas.2311995120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 11/02/2023] [Indexed: 12/21/2023] Open
Abstract
Neurons in the brain communicate with each other at their synapses. It has long been understood that this communication occurs through biochemical processes. Here, we reveal that mechanical tension in neurons is essential for communication. Using in vitro rat hippocampal neurons, we find that 1) neurons become tout/tensed after forming synapses resulting in a contractile neural network, and 2) without this contractility, neurons fail to fire. To measure time evolution of network contractility in 3D (not 2D) extracellular matrix, we developed an ultrasensitive force sensor with 1 nN resolution. We employed Multi-Electrode Array and iGluSnFR, a glutamate sensor, to quantify neuronal firing at the network and at the single synapse scale, respectively. When neuron contractility is relaxed, both techniques show significantly reduced firing. Firing resumes when contractility is restored. This finding highlights the essential contribution of neural contractility in fundamental brain functions and has implications for our understanding of neural physiology.
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Affiliation(s)
- Md Saddam Hossain Joy
- Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL61801
| | - Duncan L. Nall
- Department of Physics and Center for Biophysics and Quantitative Biology, University of Illinois Urbana-Champaign, Urbana, IL61801
| | - Bashar Emon
- Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL61801
| | - Ki Yun Lee
- Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL61801
| | - Alexandra Barishman
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL61801
| | - Movviz Ahmed
- Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, IL61801
| | - Saeedur Rahman
- Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL61801
| | - Paul R. Selvin
- Department of Physics and Center for Biophysics and Quantitative Biology, University of Illinois Urbana-Champaign, Urbana, IL61801
| | - M. Taher A. Saif
- Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL61801
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Carello-Collar G, Bellaver B, Ferreira PCL, Ferrari-Souza JP, Ramos VG, Therriault J, Tissot C, De Bastiani MA, Soares C, Pascoal TA, Rosa-Neto P, Souza DO, Zimmer ER. The GABAergic system in Alzheimer's disease: a systematic review with meta-analysis. Mol Psychiatry 2023; 28:5025-5036. [PMID: 37419974 DOI: 10.1038/s41380-023-02140-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/17/2023] [Accepted: 06/16/2023] [Indexed: 07/09/2023]
Abstract
The γ-aminobutyric acid (GABA)ergic system is the primary inhibitory neurotransmission system in the mammalian brain. Its dysregulation has been shown in multiple brain conditions, but in Alzheimer's disease (AD) studies have provided contradictory results. Here, we conducted a systematic review with meta-analysis to investigate whether the GABAergic system is altered in AD patients compared to healthy controls (HC), following the PRISMA 2020 Statement. We searched PubMed and Web of Science from database inception to March 18th, 2023 for studies reporting GABA, glutamate decarboxylase (GAD) 65/67, GABAA, GABAB, and GABAC receptors, GABA transporters (GAT) 1-3 and vesicular GAT in the brain, and GABA levels in the cerebrospinal fluid (CSF) and blood. Heterogeneity was estimated using the I2 index, and the risk of bias was assessed with an adapted questionnaire from the Joanna Briggs Institute Critical Appraisal Tools. The search identified 3631 articles, and 48 met the final inclusion criteria (518 HC, mean age 72.2, and 603 AD patients, mean age 75.6). Random-effects meta-analysis [standardized mean difference (SMD)] revealed that AD patients presented lower GABA levels in the brain (SMD = -0.48 [95% CI = -0.7, -0.27], adjusted p value (adj. p) < 0.001) and in the CSF (-0.41 [-0.72, -0.09], adj. p = 0.042), but not in the blood (-0.63 [-1.35, 0.1], adj. p = 0.176). In addition, GAD65/67 (-0.67 [-1.15, -0.2], adj. p = 0.006), GABAA receptor (-0.51 [-0.7, -0.33], adj. p < 0.001), and GABA transporters (-0.51 [-0.92, -0.09], adj. p = 0.016) were lower in the AD brain. Here, we showed a global reduction of GABAergic system components in the brain and lower GABA levels in the CSF of AD patients. Our findings suggest the GABAergic system is vulnerable to AD pathology and should be considered a potential target for developing pharmacological strategies and novel AD biomarkers.
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Affiliation(s)
- Giovanna Carello-Collar
- Graduate Program in Biological Sciences: Biochemistry, Department of Biochemistry, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil
| | - Bruna Bellaver
- Graduate Program in Biological Sciences: Biochemistry, Department of Biochemistry, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Pamela C L Ferreira
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - João Pedro Ferrari-Souza
- Graduate Program in Biological Sciences: Biochemistry, Department of Biochemistry, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Vanessa G Ramos
- Graduate Program in Biological Sciences: Biochemistry, Department of Biochemistry, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil
| | - Joseph Therriault
- McGill Centre for Studies in Aging, McGill University, Montreal, QC, H4H 1R3, Canada
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, McGill University, Montreal, QC, H4H 1R3, Canada
- Departments of Neurology and Neurosurgery, McGill University, Montreal, QC, H3A 1A1, Canada
| | - Cécile Tissot
- McGill Centre for Studies in Aging, McGill University, Montreal, QC, H4H 1R3, Canada
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, McGill University, Montreal, QC, H4H 1R3, Canada
- Departments of Neurology and Neurosurgery, McGill University, Montreal, QC, H3A 1A1, Canada
| | - Marco A De Bastiani
- Department of Pharmacology, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil
| | - Carolina Soares
- Graduate Program in Biological Sciences: Biochemistry, Department of Biochemistry, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Tharick A Pascoal
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Pedro Rosa-Neto
- McGill Centre for Studies in Aging, McGill University, Montreal, QC, H4H 1R3, Canada
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, McGill University, Montreal, QC, H4H 1R3, Canada
- Departments of Neurology and Neurosurgery, McGill University, Montreal, QC, H3A 1A1, Canada
- Montreal Neurological Institute, McGill University, Montreal, QC, H3A 2B4, Canada
| | - Diogo O Souza
- Graduate Program in Biological Sciences: Biochemistry, Department of Biochemistry, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil
- Department of Biochemistry, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil
| | - Eduardo R Zimmer
- Graduate Program in Biological Sciences: Biochemistry, Department of Biochemistry, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil.
- McGill Centre for Studies in Aging, McGill University, Montreal, QC, H4H 1R3, Canada.
- Translational Neuroimaging Laboratory, McGill University Research Centre for Studies in Aging, McGill University, Montreal, QC, H4H 1R3, Canada.
- Department of Pharmacology, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil.
- Graduate Program in Biological Sciences: Pharmacology and Therapeutics, Department of Pharmacology, Institute of Health Basic Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, 90035-003, Brazil.
- Brain Institute of Rio Grande Do Sul, Pontifical Catholic University of Rio Grande Do Sul, Porto Alegre, RS, 90610-000, Brazil.
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Ayoub CA, Wagner CS, Kuret J. Identification of gene networks mediating regional resistance to tauopathy in late-onset Alzheimer’s disease. PLoS Genet 2023; 19:e1010681. [PMID: 36972319 PMCID: PMC10079065 DOI: 10.1371/journal.pgen.1010681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 04/06/2023] [Accepted: 02/24/2023] [Indexed: 03/29/2023] Open
Abstract
Neurofibrillary lesions composed of tau protein aggregates are defining hallmarks of Alzheimer’s Disease. Despite tau filaments appearing to spread between networked brain regions in a prion-like manner, certain areas including cerebellum resist trans-synaptic spread of tauopathy and degeneration of their constituent neuronal cell bodies. To identify molecular correlates of resistance, we derived and implemented a ratio of ratios approach for disaggregating gene expression data on the basis of regional vulnerability to tauopathic neurodegeneration. When applied to vulnerable pre-frontal cortex as an internal reference for resistant cerebellum, the approach segregated adaptive changes in expression into two components. The first was enriched for neuron-derived transcripts associated with proteostasis including specific members of the molecular chaperone family and was unique to resistant cerebellum. When produced as purified proteins, each of the identified chaperones depressed aggregation of 2N4R tau in vitro at sub-stoichiometric concentrations, consistent with the expression polarity deduced from ratio of ratios testing. In contrast, the second component enriched for glia- and microglia-derived transcripts associated with neuroinflammation, segregating these pathways from susceptibility to tauopathy. These data support the utility of ratio of ratios testing for establishing the polarity of gene expression changes with respect to selective vulnerability. The approach has the potential to identify new targets for drug discovery predicated on their ability to promote resistance to disease in vulnerable neuron populations.
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Affiliation(s)
- Christopher A. Ayoub
- Biomedical Sciences Graduate Program, Ohio State University, Columbus, Ohio, United States of America
- Medical Scientist Training Program, Ohio State University, Columbus, Ohio, United States of America
- * E-mail: (CAA); (JK)
| | - Connor S. Wagner
- Department of Biological Chemistry & Pharmacology, Ohio State University, Columbus, Ohio, United States of America
| | - Jeff Kuret
- Department of Biological Chemistry & Pharmacology, Ohio State University, Columbus, Ohio, United States of America
- * E-mail: (CAA); (JK)
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Abyadeh M, Yadav VK, Kaya A. Common Molecular Signatures Between Coronavirus Infection and Alzheimer's Disease Reveal Targets for Drug Development. J Alzheimers Dis 2023; 95:995-1011. [PMID: 37638446 DOI: 10.3233/jad-230684] [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] [Indexed: 08/29/2023]
Abstract
BACKGROUND Cognitive decline is a common consequence of COVID-19, and studies suggest a link between COVID-19 and Alzheimer's disease (AD). However, the molecular mechanisms underlying this association remain unclear. OBJECTIVE To understand the potential molecular mechanisms underlying the association between COVID-19 and AD development, and identify the potential genetic targets for pharmaceutical approaches to reduce the risk or delay the development of COVID-19-related neurological pathologies. METHODS We analyzed transcriptome datasets of 638 brain samples using a novel Robust Rank Aggregation method, followed by functional enrichment, protein-protein, hub genes, gene-miRNA, and gene-transcription factor (TF) interaction analyses to identify molecular markers altered in AD and COVID-19 infected brains. RESULTS Our analyses of frontal cortex from COVID-19 and AD patients identified commonly altered genes, miRNAs and TFs. Functional enrichment and hub gene analysis of these molecular changes revealed commonly altered pathways, including downregulation of the cyclic adenosine monophosphate (cAMP) signaling and taurine and hypotaurine metabolism, alongside upregulation of neuroinflammatory pathways. Furthermore, gene-miRNA and gene-TF network analyses provided potential up- and downstream regulators of identified pathways. CONCLUSION We found that downregulation of cAMP signaling pathway, taurine metabolisms, and upregulation of neuroinflammatory related pathways are commonly altered in AD and COVID-19 pathogenesis, and may make COVID-19 patients more susceptible to cognitive decline and AD. We also identified genetic targets, regulating these pathways that can be targeted pharmaceutically to reduce the risk or delay the development of COVID-19-related neurological pathologies and AD.
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Affiliation(s)
- Morteza Abyadeh
- Department of Biology, Virginia Common wealth University, Richmond, VA, USA
| | - Vijay K Yadav
- Department of Genetics and Development, Columbia University, New York, NY, USA
| | - Alaattin Kaya
- Department of Biology, Virginia Common wealth University, Richmond, VA, USA
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Neuroprotective effect of low-dose paracetamol treatment against cognitive dysfunction in d-galactose-induced aging mice. Heliyon 2022; 8:e11108. [PMID: 36281406 PMCID: PMC9586893 DOI: 10.1016/j.heliyon.2022.e11108] [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: 01/14/2022] [Revised: 04/07/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022] Open
Abstract
Background Aging is closely associated to several deleterious conditions and cognitive impairment. Administration of low-dose paracetamol (APAP) has previously been reported to improve cognitive performance in both human and animal studies. However, the altered cognitive effects of low-dose APAP treatment in the aging brain have not been elucidated. Objectives The purpose of this study was to determine whether low-dose APAP treatment improves cognitive dysfunction in a d-galactose (d-gal)-induced aging model. Materials and methods APAP (15 and 50 mg/kg p.o.) and vitamin E (Vit E 100 mg/kg p.o.) were administered once daily to d-gal-injected mice (200 mg/kg s.c.) for 6 weeks. The elevated plus maze (EPM), open field, novel object recognition (NOR), and Morris water maze (MWM) tests, respectively, were used to measure altered neurobehavioral functions, including anxiety-like behavior and exploratory locomotor activity, as well as learning and memory performance. The gene transcription of brain-derived neurotrophic factor (BDNF)/tropomyosin receptor kinase B (TrkB) signaling in brain tissues was evaluated by real-time polymerase chain reaction. Results Compared to the control, d-gal significantly decreased exploratory locomotor activity and NOR and MWM performance but did not significantly change the activity in the EPM test. However, APAP50 and Vit E significantly reversed the effects of d-gal injection on exploratory locomotor activity. In addition, low-dose APAP (15 and 50 mg/kg) and Vit E significantly improved the reduction in NOR and MWM performance induced by d-gal. Real-time polymerase chain reaction analysis revealed that the mRNA expression of BDNF, neurotrophic tyrosine receptor kinase (NTRK), which is the gene coding TrkB receptor, and cAMP response element-binding protein (CREB) was significantly decreased in the frontal cortex and hippocampus of the d-gal mice. However, APAP50 and Vit E significantly increased BDNF and NTRK mRNA expression in both the frontal cortex and the hippocampus. A lower dose of APAP (15 mg/kg) significantly elevated the mRNA expression of NTRK, but only in the hippocampus. Moreover, APAP50 significantly increased CREB mRNA expression in the frontal cortex and hippocampus. Conclusion Low-dose APAP treatment has a neuroprotective effect on cognitive dysfunction in the d-gal aging model, and the underlying molecular mechanisms depend on the activation of BDNF/TrkB signaling.
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6
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Almeida VN, Radanovic M. Semantic processing and neurobiology in Alzheimer's disease and Mild Cognitive Impairment. Neuropsychologia 2022; 174:108337. [DOI: 10.1016/j.neuropsychologia.2022.108337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 07/17/2022] [Accepted: 07/17/2022] [Indexed: 11/28/2022]
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Patel D, Zhang X, Farrell JJ, Lunetta KL, Farrer LA. Set-Based Rare Variant Expression Quantitative Trait Loci in Blood and Brain from Alzheimer Disease Study Participants. Genes (Basel) 2021; 12:419. [PMID: 33804025 PMCID: PMC7999141 DOI: 10.3390/genes12030419] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/04/2021] [Accepted: 03/10/2021] [Indexed: 12/12/2022] Open
Abstract
Because studies of rare variant effects on gene expression have limited power, we investigated set-based methods to identify rare expression quantitative trait loci (eQTL) related to Alzheimer disease (AD). Gene-level and pathway-level cis rare-eQTL mapping was performed genome-wide using gene expression data derived from blood donated by 713 Alzheimer's Disease Neuroimaging Initiative participants and from brain tissues donated by 475 Religious Orders Study/Memory and Aging Project participants. The association of gene or pathway expression with a set of all cis potentially regulatory low-frequency and rare variants within 1 Mb of genes was evaluated using SKAT-O. A total of 65 genes expressed in the brain were significant targets for rare expression single nucleotide polymorphisms (eSNPs) among which 17% (11/65) included established AD genes HLA-DRB1 and HLA-DRB5. In the blood, 307 genes were significant targets for rare eSNPs. In the blood and the brain, GNMT, LDHC, RBPMS2, DUS2, and HP were targets for significant eSNPs. Pathway enrichment analysis revealed significant pathways in the brain (n = 9) and blood (n = 16). Pathways for apoptosis signaling, cholecystokinin receptor (CCKR) signaling, and inflammation mediated by chemokine and cytokine signaling were common to both tissues. Significant rare eQTLs in inflammation pathways included five genes in the blood (ALOX5AP, CXCR2, FPR2, GRB2, IFNAR1) that were previously linked to AD. This study identified several significant gene- and pathway-level rare eQTLs, which further confirmed the importance of the immune system and inflammation in AD and highlighted the advantages of using a set-based eQTL approach for evaluating the effect of low-frequency and rare variants on gene expression.
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Affiliation(s)
- Devanshi Patel
- Bioinformatics Graduate Program, Boston University, Boston, MA 02215, USA;
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA 02118, USA; (X.Z.); (J.J.F.)
| | - Xiaoling Zhang
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA 02118, USA; (X.Z.); (J.J.F.)
| | - John J. Farrell
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA 02118, USA; (X.Z.); (J.J.F.)
| | - Kathryn L. Lunetta
- Department of Biostatistics, Boston University School of Public Health, Boston, MA 02118, USA;
| | - Lindsay A. Farrer
- Bioinformatics Graduate Program, Boston University, Boston, MA 02215, USA;
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA 02118, USA; (X.Z.); (J.J.F.)
- Department of Biostatistics, Boston University School of Public Health, Boston, MA 02118, USA;
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA 02118, USA
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
- Department of Epidemiology, Boston University School of Public Health, Boston, MA 02118, USA
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Jayatunga DPW, Hone E, Bharadwaj P, Garg M, Verdile G, Guillemin GJ, Martins RN. Targeting Mitophagy in Alzheimer's Disease. J Alzheimers Dis 2020; 78:1273-1297. [PMID: 33285629 DOI: 10.3233/jad-191258] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mitochondria perform many essential cellular functions including energy production, calcium homeostasis, transduction of metabolic and stress signals, and mediating cell survival and death. Maintaining viable populations of mitochondria is therefore critical for normal cell function. The selective disposal of damaged mitochondria, by a pathway known as mitophagy, plays a key role in preserving mitochondrial integrity and quality. Mitophagy reduces the formation of reactive oxygen species and is considered as a protective cellular process. Mitochondrial dysfunction and deficits of mitophagy have important roles in aging and especially in neurodegenerative disorders such as Alzheimer's disease (AD). Targeting mitophagy pathways has been suggested to have potential therapeutic effects against AD. In this review, we aim to briefly discuss the emerging concepts on mitophagy, molecular regulation of the mitophagy process, current mitophagy detection methods, and mitophagy dysfunction in AD. Finally, we will also briefly examine the stimulation of mitophagy as an approach for attenuating neurodegeneration in AD.
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Affiliation(s)
- Dona P W Jayatunga
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - Eugene Hone
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Cooperative Research Centre for Mental Health, Carlton, VIC, Australia
| | - Prashant Bharadwaj
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Cooperative Research Centre for Mental Health, Carlton, VIC, Australia
| | - Manohar Garg
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia.,Riddet Institute, Massey University, Palmerston North, New Zealand
| | - Giuseppe Verdile
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
| | - Gilles J Guillemin
- Department of Pharmacology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia.,St. Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
| | - Ralph N Martins
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Australian Alzheimer's Research Foundation, Ralph and Patricia Sarich Neuroscience Research Institute, Nedlands, WA, Australia.,Department of Biomedical Sciences, Macquarie University, Sydney, NSW, Australia.,School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia.,KaRa Institute of Neurological Diseases, Sydney, NSW, Australia
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9
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Murueta-Goyena A, Ortuzar N, Lafuente JV, Bengoetxea H. Enriched Environment Reverts Somatostatin Interneuron Loss in MK-801 Model of Schizophrenia. Mol Neurobiol 2019; 57:125-134. [PMID: 31506899 DOI: 10.1007/s12035-019-01762-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 08/29/2019] [Indexed: 02/02/2023]
Abstract
Dysregulation of the inhibitory drive has been proposed to be a central mechanism to explain symptoms and pathophysiological hallmarks in schizophrenia. A number of recent neuroanatomical studies suggest that certain types of inhibitory cells are deficient in schizophrenia, including somatostatin-immunoreactive interneurons (SST+). The present study sought to use stereological methods to investigate whether the number of SST+ interneurons decreased after repeated injections of NMDA receptor antagonist MK-801 (0.5 mg/kg) and to determine the effect of limited exposure to an enriched environment (EE) in adult life on this sub-population of inhibitory cells. Considering that somatostatin expression is highly dependent on neurotrophic support, we explored the changes in the relative expression of proteins related to brain-derived neurotrophic factor-tyrosine kinase B (BDNF-TrkB) signaling between the experimental groups. We observed that early-life MK-801 treatment significantly decreased the number of SST+ interneurons in the medial prefrontal cortex (mPFC) and the hippocampus (HPC) of adult Long Evans rats. Contrarily, short-term exposure to EE increased the number of SST+ interneurons in MK-801-injected animals, except in the CA1 region of the hippocampus, whereas this increase was not observed in vehicle-injected rats. We also found upregulated BDNF-TrkB signaling after EE that triggered an increase in the pERK/ERK ratio in mPFC and HPC, and the pAkt/Akt ratio in HPC. Thus, the present results support the notion that SST+ interneurons are markedly affected after early-life NMDAR blockade and that EE promotes SST+ interneuron expression, which is partly mediated through the BDNF-TrkB signaling pathway. These results may have important implications for schizophrenia, as SST+ interneuron loss is also observed in the MK-801 pre-clinical model, and its expression can be rescued by non-pharmacological approaches.
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Affiliation(s)
- Ane Murueta-Goyena
- Laboratory of Clinical and Experimental Neuroscience, Department of Neuroscience, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain. .,Neurodegenerative Diseases group, BioCruces Bizkaia Health Research Institute, Plaza de Cruces 12, 48903, Barakaldo, Bizkaia, Spain.
| | - Naiara Ortuzar
- Laboratory of Clinical and Experimental Neuroscience, Department of Neuroscience, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain
| | - José Vicente Lafuente
- Laboratory of Clinical and Experimental Neuroscience, Department of Neuroscience, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain.,Nanoneurosurgery Group, BioCruces Bizkaia Health Research Institute, Plaza de Cruces 12, 48903, Barakaldo, Bizkaia, Spain
| | - Harkaitz Bengoetxea
- Laboratory of Clinical and Experimental Neuroscience, Department of Neuroscience, University of the Basque Country, UPV/EHU, Leioa, Bizkaia, Spain
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Majdi A, Sadigh-Eteghad S, Talebi M, Farajdokht F, Erfani M, Mahmoudi J, Gjedde A. Nicotine Modulates Cognitive Function in D-Galactose-Induced Senescence in Mice. Front Aging Neurosci 2018; 10:194. [PMID: 30061821 PMCID: PMC6055060 DOI: 10.3389/fnagi.2018.00194] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 06/08/2018] [Indexed: 01/21/2023] Open
Abstract
Here, we tested the claim that nicotine attenuates the signs of brain dysfunction in the model of brain aging induced by D-galactose (DGal) in mice. We administered nicotine at doses of 0.1, 0.5 and 1 mg/kg by the subcutaneous (s.c.) or at 0.1 mg/kg by the intranasal (i.n.) routes in mice that had received DGal at the dose of 500 mg/kg subcutaneous (s.c.) for 6 weeks. We assessed animal withdrawal signs as the number of presented somatic signs, thermal hyperalgesia, elevated plus maze (EPM) and open field tests. We evaluated spatial memory and recognition with Barnes maze and novel object recognition (NOR) tests. We tested brain tissue for reactive oxygen species (ROS), mitochondrial membrane potential, caspase-3, Bax, Bcl-2, cytochrome C, brain-derived neurotrophic factor and nerve growth factor levels. Nicotine administration in model groups (0.5 mg/kg s.c. and 0.1 mg/kg i.n. doses) significantly attenuated impairment of spatial and episodic memories in comparison to normal saline-received model group. These doses also reduced mito-oxidative damage as well as apoptosis and raised neurotrophic factors level in model groups in comparison to normal saline-received model group. The 1 mg/kg s.c. dose nicotine revealed withdrawal signs compared with the other nicotine-received groups. Nicotine at specific doses and routes has the potential to attenuate age-related cognitive impairment, mito-oxidative damage, and apoptosis. The doses raise neurotrophic factors without producing withdrawal signs.
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Affiliation(s)
- Alireza Majdi
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saeed Sadigh-Eteghad
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mahnaz Talebi
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Fereshteh Farajdokht
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Marjan Erfani
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Javad Mahmoudi
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Albert Gjedde
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Departments of Clinical Research and Nuclear Medicine, Odense University Hospital, University of Southern Denmark, Odense, Denmark
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, United States
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11
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Hermans L, Levin O, Maes C, van Ruitenbeek P, Heise KF, Edden RAE, Puts NAJ, Peeters R, King BR, Meesen RLJ, Leunissen I, Swinnen SP, Cuypers K. GABA levels and measures of intracortical and interhemispheric excitability in healthy young and older adults: an MRS-TMS study. Neurobiol Aging 2018; 65:168-177. [PMID: 29494863 DOI: 10.1016/j.neurobiolaging.2018.01.023] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 01/24/2018] [Accepted: 01/26/2018] [Indexed: 12/24/2022]
Abstract
Edited magnetic resonance spectroscopy (MRS) and transcranial magnetic stimulation (TMS) have often been used to study the integrity of the GABAergic neurotransmission system in healthy aging. To investigate whether the measurement outcomes obtained with these 2 techniques are associated with each other in older human adults, gamma-aminobutyric acid (GABA) levels in the left sensorimotor cortex were assessed with edited MRS in 28 older (63-74 years) and 28 young adults (19-34 years). TMS at rest was then used to measure intracortical inhibition (short-interval intracortical inhibition/long-interval intracortical inhibition), intracortical facilitation, interhemispheric inhibition from left to right primary motor cortex (M1) and recruitment curves of left and right M1. Our observations showed that short-interval intracortical inhibition and long-interval intracortical inhibition in the left M1 were reduced in older adults, while GABA levels did not significantly differ between age groups. Furthermore, MRS-assessed GABA within left sensorimotor cortex was not correlated with TMS-assessed cortical excitability or inhibition. These observations suggest that healthy aging gives rise to altered inhibition at the postsynaptic receptor level, which does not seem to be associated with MRS-assessed GABA+ levels.
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Affiliation(s)
- Lize Hermans
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Oron Levin
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Celine Maes
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Peter van Ruitenbeek
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium; Department of Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, MD, the Netherlands
| | - Kirstin-Friederike Heise
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Richard A E Edden
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA; Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Nicolaas A J Puts
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA; Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Ronald Peeters
- Department of Imaging & Pathology, Biomedical Sciences Group, KU Leuven, Leuven, Belgium
| | - Bradley R King
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Raf L J Meesen
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium; Rehabilitation Research Centre, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium
| | - Inge Leunissen
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium
| | - Stephan P Swinnen
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium; Leuven Research Institute for Neuroscience & Disease (LIND), KU Leuven, Leuven, Belgium
| | - Koen Cuypers
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium; Rehabilitation Research Centre, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium.
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12
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Weisz F, Piccinin S, Mango D, Ngomba RT, Mercuri NB, Nicoletti F, Nisticò R. The role of adiponectin receptors in the regulation of synaptic transmission in the hippocampus. Synapse 2017; 71. [PMID: 28187508 DOI: 10.1002/syn.21964] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 02/02/2017] [Accepted: 02/06/2017] [Indexed: 12/15/2022]
Abstract
In the last two decades adiponectin, member of the adipokines family, gained attention because of its unique antidiabetic effects. However, the presence in the brain of adiponectin receptors and adiponectin itself raised interest because of the possible association with neuropsychiatric diseases. Indeed, clinical studies found altered concentration of adiponectin both in plasma and cerebrospinal fluid in several pathologies including depression, multiple sclerosis, Alzheimer's disease and stroke. Moreover, recent preclinical studies also suggest its involvement in different physiological functions. Despite this evidence very few studies attempted to elucidate the functional role of adiponectin at the synapse. To address this question, here we investigated the effect of Adiporon, an agonist of both adiponectin receptors on synaptic transmission and LTP at Schaffer-collateral CA1 pathway. Surprisingly, increasing concentration of Adiporon correlated with lower CA1-LTP levels and paired-pulse ratio, whereas basal transmission was always preserved. Collectively, our data show that the adiponectin system, beyond its involvement in metabolic diseases, plays also a critical role in synaptic activity thereby representing a putative target for the treatment of synaptic pathologies.
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Affiliation(s)
- Filippo Weisz
- Department of Pharmacology of Synaptic Plasticity Lab, Fondazione EBRI-Rita Levi Montalcini, Rome, Italy.,Department of Physiology and Pharmacology Erspamer, University of Rome "La Sapienza", Rome, Italy
| | - Sonia Piccinin
- Department of Pharmacology of Synaptic Plasticity Lab, Fondazione EBRI-Rita Levi Montalcini, Rome, Italy.,Department of Physiology and Pharmacology Erspamer, University of Rome "La Sapienza", Rome, Italy
| | - Dalila Mango
- Department of Pharmacology of Synaptic Plasticity Lab, Fondazione EBRI-Rita Levi Montalcini, Rome, Italy.,Department of Physiology and Pharmacology Erspamer, University of Rome "La Sapienza", Rome, Italy
| | | | | | - Ferdinando Nicoletti
- Department of Physiology and Pharmacology Erspamer, University of Rome "La Sapienza", Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Robert Nisticò
- Department of Pharmacology of Synaptic Plasticity Lab, Fondazione EBRI-Rita Levi Montalcini, Rome, Italy.,University of Rome "Tor Vergata", Rome, Italy
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13
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Discovery of Novel Biomarkers for Alzheimer's Disease from Blood. DISEASE MARKERS 2016; 2016:4250480. [PMID: 27418712 PMCID: PMC4932164 DOI: 10.1155/2016/4250480] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 05/04/2016] [Indexed: 12/20/2022]
Abstract
Blood-based biomarkers for Alzheimer's disease would be very valuable because blood is a more accessible biofluid and is suitable for repeated sampling. However, currently there are no robust and reliable blood-based biomarkers for practical diagnosis. In this study we used a knowledge-based protein feature pool and two novel support vector machine embedded feature selection methods to find panels consisting of two and three biomarkers. We validated these biomarker sets using another serum cohort and an RNA profile cohort from the brain. Our panels included the proteins ECH1, NHLRC2, HOXB7, FN1, ERBB2, and SLC6A13 and demonstrated promising sensitivity (>87%), specificity (>91%), and accuracy (>89%).
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14
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Huang T, Wang Z, Wei L, Kindy M, Zheng Y, Xi T, Gao BZ. Microelectrode Array-evaluation of Neurotoxic Effects of Magnesium as an Implantable Biomaterial. JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY 2016; 32:89-96. [PMID: 27110081 PMCID: PMC4840281 DOI: 10.1016/j.jmst.2015.08.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Magnesium (Mg)-based biomaterials have shown great potential in clinical applications. However, the cytotoxic effects of excessive Mg2+ and the corrosion products from Mg-based biomaterials, particularly their effects on neurons, have been little studied. Although viability tests are most commonly used, a functional evaluation is critically needed. Here, both methyl thiazolyl tetrazolium (MTT) and lactate dehydrogenase (LDH) assays were used to test the effect of Mg2+ and Mg-extract solution on neuronal viability. Microelectrode arrays (MEAs), which provide long-term, real-time recording of extracellular electrophysiological signals of in vitro neuronal networks, were used to test for toxic effects. The minimum effective concentrations (ECmin) of Mg2+ from the MTT and LDH assays were 3 mmol/L and 100 mmol/L, respectively, while the ECmin obtained from the MEA assay was 0.1 mmol/L. MEA data revealed significant loss of neuronal network activity when the culture was exposed to 25% Mg-extract solution, a concentration that did not affect neuronal viability. For evaluating the biocompatibility of Mg-based biomaterials with neurons, MEA electrophysiological testing is a more precise method than basic cell-viability testing.
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Affiliation(s)
- Ting Huang
- Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Zhonghai Wang
- Department of Bioengineering, Clemson University, Clemson, SC 29634, USA
| | - Lina Wei
- Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Mark Kindy
- Department of Bioengineering, Clemson University, Clemson, SC 29634, USA
- Departments of Neurosciences and Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29466, USA
- Ralph H. Johnson VA Medical Center, Charleston, SC 29403, USA
| | - Yufeng Zheng
- Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China
| | - Tingfei Xi
- Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- Shenzhen Key Laboratory of Human Tissue Regeneration and Repair, Shenzhen Institute, Peking University, Shenzhen 518057, China
| | - Bruce Z. Gao
- Department of Bioengineering, Clemson University, Clemson, SC 29634, USA
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15
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Guidi M, Rani A, Karic S, Severance B, Kumar A, Foster TC. Contribution of N-methyl-D-aspartate receptors to attention and episodic spatial memory during senescence. Neurobiol Learn Mem 2015; 125:36-46. [PMID: 26234588 DOI: 10.1016/j.nlm.2015.07.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 06/22/2015] [Accepted: 07/24/2015] [Indexed: 01/06/2023]
Abstract
A decrease in N-methyl-D-aspartate receptor (NMDAR) function is associated with age-related cognitive impairments. However, NMDAR antagonists are prescribed for cognitive decline associated with age-related neurodegenerative disease, raising questions as to the role of NMDAR activity in cognitive function during aging. The current studies examined effects of NMDAR blockade on cognitive task that are sensitive to aging. Young and middle-age rats were trained on the five-choice serial reaction time task (5-CSRTT) and challenged with MK-801 (0.025, 0.05, and 0.1mg/kg or vehicle). Attention deficits were apparent in middle-age and performance of young and middle-age rats was enhanced for low doses of MK-801 (0.025 and 0.05). The beneficial effects on attention were reversed by the highest dose of MK-801. Older animals exhibited a delay-dependent impairment of episodic spatial memory examined on a delayed-matching to place water maze task. Similarly, a low dose of MK-801 (0.05mg/kg) impaired performance with increasing delay and aged animals were more susceptible to disruption by NMDAR blockade. Despite MK-801 impairment of episodic spatial memory, MK-801 had minimal effects on spatial reference memory. Our results confirm that NMDARs contribute to rapidly acquired and flexible spatial memory and support the idea that a decline in NMDAR function contributes to the age-related impairments in cognition.
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Affiliation(s)
- Michael Guidi
- Noldus Information Technology, 1503 Edwards Ferry Road, Suite 310, Leesburg, VA 20176, USA
| | - Asha Rani
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Semir Karic
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Barrett Severance
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Ashok Kumar
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA.
| | - Thomas C Foster
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA.
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16
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Weible AP, Moore AK, Liu C, DeBlander L, Wu H, Kentros C, Wehr M. Perceptual gap detection is mediated by gap termination responses in auditory cortex. Curr Biol 2015; 24:1447-55. [PMID: 24980499 DOI: 10.1016/j.cub.2014.05.031] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 05/02/2014] [Accepted: 05/14/2014] [Indexed: 12/31/2022]
Abstract
BACKGROUND Understanding speech in the presence of background noise often becomes increasingly difficult with age. These age-related speech processing deficits reflect impairments in temporal acuity. Gap detection is a model for temporal acuity in speech processing in which a gap inserted in white noise acts as a cue that attenuates subsequent startle responses. Lesion studies have shown that auditory cortex is necessary for the detection of brief gaps, and auditory cortical neurons respond to the end of the gap with a characteristic burst of spikes called the gap termination response (GTR). However, it remains unknown whether and how the GTR plays a causal role in gap detection. We tested this by optogenetically suppressing the activity of somatostatin- or parvalbumin-expressing inhibitory interneurons, or CaMKII-expressing excitatory neurons, in auditory cortex of behaving mice during specific epochs of a gap detection protocol. RESULTS Suppressing interneuron activity during the postgap interval enhanced gap detection. Suppressing excitatory cells during this interval attenuated gap detection. Suppressing activity preceding the gap had the opposite behavioral effects, whereas prolonged suppression across both intervals had no effect on gap detection. CONCLUSIONS In addition to confirming cortical involvement, we demonstrate here for the first time a causal relationship between postgap neural activity and perceptual gap detection. Furthermore, our results suggest that gap detection involves an ongoing comparison of pre- and postgap spiking activity. Finally, we propose a simple yet biologically plausible neural circuit that reproduces each of these neural and behavioral results.
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Affiliation(s)
- Aldis P Weible
- Institute of Neuroscience, University of Oregon, Eugene, OR 97405, USA
| | - Alexandra K Moore
- Institute of Neuroscience, University of Oregon, Eugene, OR 97405, USA
| | - Christine Liu
- Institute of Neuroscience, University of Oregon, Eugene, OR 97405, USA
| | - Leah DeBlander
- Institute of Neuroscience, University of Oregon, Eugene, OR 97405, USA
| | - Haiyan Wu
- Institute of Neuroscience, University of Oregon, Eugene, OR 97405, USA
| | - Clifford Kentros
- Institute of Neuroscience, University of Oregon, Eugene, OR 97405, USA; Kavli Institute, 7491 Trondheim, Norway
| | - Michael Wehr
- Institute of Neuroscience, University of Oregon, Eugene, OR 97405, USA.
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17
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Roselli F, Caroni P. From Intrinsic Firing Properties to Selective Neuronal Vulnerability in Neurodegenerative Diseases. Neuron 2015; 85:901-10. [DOI: 10.1016/j.neuron.2014.12.063] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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18
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Kumar D, Thakur MK. Age-related expression of Neurexin1 and Neuroligin3 is correlated with presynaptic density in the cerebral cortex and hippocampus of male mice. AGE (DORDRECHT, NETHERLANDS) 2015; 37:17. [PMID: 25693924 PMCID: PMC4332888 DOI: 10.1007/s11357-015-9752-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Accepted: 01/26/2015] [Indexed: 05/19/2023]
Abstract
Neurexin1 (Nrxn1) and Neuroligin3 (Nlgn3) are cell adhesion proteins, which play an important role in synaptic plasticity that declines with advancing age. However, the expression of these proteins during aging has not been analyzed. In the present study, we have examined the age-related changes in the expression of these proteins in cerebral cortex and hippocampus of 10-, 30-, 50-, and 80-week-old male mice. Reverse transcriptase polymerase chain reaction (RT-PCR) analysis indicated that messenger RNA (mRNA) level of Nrxn1 and Nlgn3 significantly increased from 10 to 30 weeks and then decreased at 50 weeks in both the regions. However, in 80-week-old mice, Nrxn1 and Nlgn3 were further downregulated in cerebral cortex while Nrxn1 was downregulated and Nlgn3 was upregulated in hippocampus. These findings were corroborated by immunoblotting and immunofluorescence results. When the expression of Nrxn1 and Nlgn3 was correlated with presynaptic density marker synaptophysin, it was found that synaptophysin protein expression in cerebral cortex was high at 10 weeks and decreased gradually up to 80 weeks, whereas in hippocampus, it decreased until 50 weeks and then increased remarkably at 80 weeks. Furthermore, Pearson's correlation analysis showed that synaptophysin had a strong relation with Nrxn1 and Nlgn3 in cerebral cortex and with Nlgn3 in hippocampus. Thus, these findings showed that Nrxn1 and Nlgn3 are differentially expressed in cerebral cortex and hippocampus which might be responsible for alterations in synaptic plasticity during aging.
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Affiliation(s)
- Dhiraj Kumar
- Biochemistry and Molecular Biology Laboratory, Brain Research Centre, Department of Zoology, Banaras Hindu University, Varanasi, 221005 India
| | - M. K. Thakur
- Biochemistry and Molecular Biology Laboratory, Brain Research Centre, Department of Zoology, Banaras Hindu University, Varanasi, 221005 India
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19
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Sherman-Baust CA, Kuhn E, Valle BL, Shih IM, Kurman RJ, Wang TL, Amano T, Ko MSH, Miyoshi I, Araki Y, Lehrmann E, Zhang Y, Becker KG, Morin PJ. A genetically engineered ovarian cancer mouse model based on fallopian tube transformation mimics human high-grade serous carcinoma development. J Pathol 2014; 233:228-37. [PMID: 24652535 DOI: 10.1002/path.4353] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 02/25/2014] [Accepted: 03/11/2014] [Indexed: 12/18/2022]
Abstract
Recent evidence suggests that ovarian high-grade serous carcinoma (HGSC) originates from the epithelium of the fallopian tube. However, most mouse models are based on the previous prevailing view that ovarian cancer develops from the transformation of the ovarian surface epithelium. Here, we report the extensive histological and molecular characterization of the mogp-TAg transgenic mouse, which expresses the SV40 large T-antigen (TAg) under the control of the mouse müllerian-specific Ovgp-1 promoter. Histological analysis of the fallopian tubes of mogp-TAg mice identified a variety of neoplastic lesions analogous to those described as precursors to ovarian HGSC. We identified areas of normal-appearing p53-positive epithelium that are similar to 'p53 signatures' in the human fallopian tube. More advanced proliferative lesions with nuclear atypia and epithelial stratification were also identified that were morphologically and immunohistochemically reminiscent of human serous tubal intraepithelial carcinoma (STIC), a potential precursor of ovarian HGSC. Beside these non-invasive precursor lesions, we also identified invasive adenocarcinoma in the ovaries of 56% of the mice. Microarray analysis revealed several genes differentially expressed between the fallopian tube of mogp-TAg and wild-type (WT) C57BL/6. One of these genes, Top2a, which encodes topoisomerase IIα, was shown by immunohistochemistry to be concurrently expressed with elevated p53 and was specifically elevated in mouse STICs but not in the surrounding tissues. TOP2A protein was also found elevated in human STICs, low-grade and high-grade serous carcinoma. The mouse model reported here displays a progression from normal tubal epithelium to invasive HGSC in the ovary, and therefore closely simulates the current emerging model of human ovarian HGSC pathogenesis. This mouse therefore has the potential to be a very useful new model for elucidating the mechanisms of serous ovarian tumourigenesis, as well as for developing novel approaches for the prevention, diagnosis and therapy of this disease.
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Affiliation(s)
- Cheryl A Sherman-Baust
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, Baltimore, MD, USA
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20
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Neuropsin Expression Correlates with Dendritic Marker MAP2c Level in Different Brain Regions of Aging Mice. Mol Neurobiol 2014; 51:1130-8. [PMID: 24965600 DOI: 10.1007/s12035-014-8780-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 06/09/2014] [Indexed: 10/25/2022]
Abstract
Neuropsin (NP) is a serine protease, implicated in synaptic plasticity and memory acquisition through cleavage of synaptic adhesion molecule, L1CAM. However, NP has not been explored during brain aging that entails drastic deterioration of plasticity and memory with selective regional vulnerability. Therefore, we have analysed the expression of NP and correlated with its function via analysis of endogenous cleavage of L1CAM and level of dendritic marker MAP2c in different regions of the aging mouse brain. While NP expression gradually decreased in the cerebral cortex during aging, it showed a sharp rise in both olfactory bulb and hippocampus in adult and thereafter declined in old age. NP expression was moderate in young medulla, but undetectable in midbrain and cerebellum. It was positively correlated with L1CAM cleavage and MAP2c level in different brain regions during aging. Taken together, our study shows age-dependent regional variation in NP expression and its positive correlation with MAP2c level, suggesting the involvement of NP in MAP2c mediated alterations in dendritic morphology during aging.
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21
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Stevens JB, Liu G, Abdallah BY, Horne SD, Ye KJ, Bremer SW, Ye CJ, Krawetz SA, Heng HH. Unstable genomes elevate transcriptome dynamics. Int J Cancer 2014; 134:2074-87. [PMID: 24122714 DOI: 10.1002/ijc.28531] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 09/10/2013] [Accepted: 09/26/2013] [Indexed: 01/15/2023]
Abstract
The challenge of identifying common expression signatures in cancer is well known, however the reason behind this is largely unclear. Traditionally variation in expression signatures has been attributed to technological problems, however recent evidence suggests that chromosome instability (CIN) and resultant karyotypic heterogeneity may be a large contributing factor. Using a well-defined model of immortalization, we systematically compared the pattern of genome alteration and expression dynamics during somatic evolution. Co-measurement of global gene expression and karyotypic alteration throughout the immortalization process reveals that karyotype changes influence gene expression as major structural and numerical karyotypic alterations result in large gene expression deviation. Replicate samples from stages with stable genomes are more similar to each other than are replicate samples with karyotypic heterogeneity. Karyotypic and gene expression change during immortalization is dynamic as each stage of progression has a unique expression pattern. This was further verified by comparing global expression in two replicates grown in one flask with known karyotypes. Replicates with higher karyotypic instability were found to be less similar than replicates with stable karyotypes. This data illustrates the karyotype, transcriptome, and transcriptome determined pathways are in constant flux during somatic cellular evolution (particularly during the macroevolutionary phase) and this flux is an inextricable feature of CIN and essential for cancer formation. The findings presented here underscore the importance of understanding the evolutionary process of cancer in order to design improved treatment modalities.
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22
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Griffith WH, Dubois DW, Fincher A, Peebles KA, Bizon JL, Murchison D. Characterization of age-related changes in synaptic transmission onto F344 rat basal forebrain cholinergic neurons using a reduced synaptic preparation. J Neurophysiol 2013; 111:273-86. [PMID: 24133226 DOI: 10.1152/jn.00129.2013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Basal forebrain (BF) cholinergic neurons participate in a number of cognitive processes that become impaired during aging. We previously found that age-related enhancement of Ca(2+) buffering in rat cholinergic BF neurons was associated with impaired performance in the water maze spatial learning task (Murchison D, McDermott AN, Lasarge CL, Peebles KA, Bizon JL, and Griffith WH. J Neurophysiol 102: 2194-2207, 2009). One way that altered Ca(2+) buffering could contribute to cognitive impairment involves synaptic function. In this report we show that synaptic transmission in the BF is altered with age and cognitive status. We have examined the properties of spontaneous postsynaptic currents (sPSCs) in cholinergic BF neurons that have been mechanically dissociated without enzymes from behaviorally characterized F344 rats. These isolated neurons retain functional presynaptic terminals on their somata and proximal dendrites. Using whole cell patch-clamp recording, we show that sPSCs and miniature PSCs are predominately GABAergic (bicuculline sensitive) and in all ways closely resemble PSCs recorded in a BF in vitro slice preparation. Adult (4-7 mo) and aged (22-24 mo) male rats were cognitively assessed using the water maze. Neuronal phenotype was identified post hoc using single-cell RT-PCR. The frequency of sPSCs was reduced during aging, and this was most pronounced in cognitively impaired subjects. This is the same population that demonstrated increased intracellular Ca(2+) buffering. We also show that increasing Ca(2+) buffering in the synaptic terminals of young BF neurons can mimic the reduced frequency of sPSCs observed in aged BF neurons.
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Affiliation(s)
- William H Griffith
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M Health Science Center, Bryan, Texas; and
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23
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Saxena S, Roselli F, Singh K, Leptien K, Julien JP, Gros-Louis F, Caroni P. Neuroprotection through Excitability and mTOR Required in ALS Motoneurons to Delay Disease and Extend Survival. Neuron 2013; 80:80-96. [DOI: 10.1016/j.neuron.2013.07.027] [Citation(s) in RCA: 170] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2013] [Indexed: 12/13/2022]
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24
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Kipanyula MJ, Contreras L, Zampese E, Lazzari C, Wong AKC, Pizzo P, Fasolato C, Pozzan T. Ca2+ dysregulation in neurons from transgenic mice expressing mutant presenilin 2. Aging Cell 2012; 11:885-93. [PMID: 22805202 DOI: 10.1111/j.1474-9726.2012.00858.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Mutations in amyloid precursor protein (APP), and presenilin-1 and presenilin-2 (PS1 and PS2) have causally been implicated in Familial Alzheimer's Disease (FAD), but the mechanistic link between the mutations and the early onset of neurodegeneration is still debated. Although no consensus has yet been reached, most data suggest that both FAD-linked PS mutants and endogenous PSs are involved in cellular Ca2+ homeostasis. We here investigated subcellular Ca2+ handling in primary neuronal cultures and acute brain slices from wild type and transgenic mice carrying the FAD-linked PS2-N141I mutation, either alone or in the presence of the APP Swedish mutation. Compared with wild type, both types of transgenic neurons show a similar reduction in endoplasmic reticulum (ER) Ca2+ content and decreased response to metabotropic agonists, albeit increased Ca2+ release induced by caffeine. In both transgenic neurons, we also observed a higher ER-mitochondria juxtaposition that favors increased mitochondrial Ca2+ uptake upon ER Ca2+ release. A model is described that integrates into a unifying hypothesis the contradictory effects on Ca2+ homeostasis of different PS mutations and points to the relevance of these findings in neurodegeneration and aging.
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Gleichmann M, Chow VW, Mattson MP. Homeostatic disinhibition in the aging brain and Alzheimer's disease. J Alzheimers Dis 2012; 24:15-24. [PMID: 21187584 DOI: 10.3233/jad-2010-101674] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this article, we propose that impaired efficiency of glutamatergic synaptic transmission and a compensatory reduction in inhibitory neurotransmission, a process called homeostatic disinhibition, occurs in the aging brain and more dramatically in Alzheimer's disease (AD). Homeostatic disinhibition may help understand certain features of the aging brain and AD, including: 1) the increased risk for epileptic seizures, especially in the early phase of the disease; 2) the reduced ability to generate γ-oscillations; and 3) the increase in neuronal activity as measured by functional MRI. Homeostatic disinhibition may be the major mechanism that activates cognitive reserve. Modulating neuronal activity may therefore be a viable therapeutic strategy in AD that can complement existing anti-amyloid strategies. Specifically, enhancing endogenous glutamatergic synaptic transmission through increased co-agonist signaling or through positive allosteric modulation of metabotropic glutamatergic receptors appears as an attractive strategy. Alternatively, further reduction of GABAergic signaling may work as well, although care has to be taken to prevent epileptic seizures.
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Affiliation(s)
- Marc Gleichmann
- Laboratory of Neurosciences, National Institute on Aging, Baltimore, MD, USA
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26
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Tremblay MÈ, Zettel ML, Ison JR, Allen PD, Majewska AK. Effects of aging and sensory loss on glial cells in mouse visual and auditory cortices. Glia 2012; 60:541-58. [PMID: 22223464 DOI: 10.1002/glia.22287] [Citation(s) in RCA: 229] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 12/05/2011] [Indexed: 12/11/2022]
Abstract
Normal aging is often accompanied by a progressive loss of receptor sensitivity in hearing and vision, whose consequences on cellular function in cortical sensory areas have remained largely unknown. By examining the primary auditory (A1) and visual (V1) cortices in two inbred strains of mice undergoing either age-related loss of audition (C57BL/6J) or vision (CBA/CaJ), we were able to describe cellular and subcellular changes that were associated with normal aging (occurring in A1 and V1 of both strains) or specifically with age-related sensory loss (only in A1 of C57BL/6J or V1 of CBA/CaJ), using immunocytochemical electron microscopy and light microscopy. While the changes were subtle in neurons, glial cells and especially microglia were transformed in aged animals. Microglia became more numerous and irregularly distributed, displayed more variable cell body and process morphologies, occupied smaller territories, and accumulated phagocytic inclusions that often displayed ultrastructural features of synaptic elements. Additionally, evidence of myelination defects were observed, and aged oligodendrocytes became more numerous and were more often encountered in contiguous pairs. Most of these effects were profoundly exacerbated by age-related sensory loss. Together, our results suggest that the age-related alteration of glial cells in sensory cortical areas can be accelerated by activity-driven central mechanisms that result from an age-related loss of peripheral sensitivity. In light of our observations, these age-related changes in sensory function should be considered when investigating cellular, cortical, and behavioral functions throughout the lifespan in these commonly used C57BL/6J and CBA/CaJ mouse models.
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Affiliation(s)
- Marie-Ève Tremblay
- Department of Neurobiology and Anatomy and Center for Visual Science, University of Rochester, Rochester, New York 14642, USA
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Martel G, Dutar P, Epelbaum J, Viollet C. Somatostatinergic systems: an update on brain functions in normal and pathological aging. Front Endocrinol (Lausanne) 2012; 3:154. [PMID: 23230430 PMCID: PMC3515867 DOI: 10.3389/fendo.2012.00154] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 11/20/2012] [Indexed: 11/29/2022] Open
Abstract
Somatostatin is highly expressed in mammalian brain and is involved in many brain functions such as motor activity, sleep, sensory, and cognitive processes. Five somatostatin receptors have been described: sst(1), sst(2) (A and B), sst(3), sst(4), and sst(5), all belonging to the G-protein-coupled receptor family. During the recent years, numerous studies contributed to clarify the role of somatostatin systems, especially long-range somatostatinergic interneurons, in several functions they have been previously involved in. New advances have also been made on the alterations of somatostatinergic systems in several brain diseases and on the potential therapeutic target they represent in these pathologies.
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Affiliation(s)
| | | | | | - Cécile Viollet
- *Correspondence: Cécile Viollet, Inserm UMR894 - Center for Psychiatry and Neuroscience, Université Paris Descartes, Sorbonne Paris Cité, 2 ter rue d’Alésia, 75014 Paris, France. e-mail:
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Sherman-Baust CA, Becker KG, Wood III WH, Zhang Y, Morin PJ. Gene expression and pathway analysis of ovarian cancer cells selected for resistance to cisplatin, paclitaxel, or doxorubicin. J Ovarian Res 2011; 4:21. [PMID: 22141344 PMCID: PMC3259089 DOI: 10.1186/1757-2215-4-21] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 12/05/2011] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Resistance to current chemotherapeutic agents is a major cause of therapy failure in ovarian cancer patients, but the exact mechanisms leading to the development of drug resistance remain unclear. METHODS To better understand mechanisms of drug resistance, and possibly identify novel targets for therapy, we generated a series of drug resistant ovarian cancer cell lines through repeated exposure to three chemotherapeutic drugs (cisplatin, doxorubicin, or paclitaxel), and identified changes in gene expression patterns using Illumina whole-genome expression microarrays. Validation of selected genes was performed by RT-PCR and immunoblotting. Pathway enrichment analysis using the KEGG, GO, and Reactome databases was performed to identify pathways that may be important in each drug resistance phenotype. RESULTS A total of 845 genes (p < 0.01) were found altered in at least one drug resistance phenotype when compared to the parental, drug sensitive cell line. Focusing on each resistance phenotype individually, we identified 460, 366, and 337 genes significantly altered in cells resistant to cisplatin, doxorubicin, and paclitaxel, respectively. Of the 845 genes found altered, only 62 genes were simultaneously altered in all three resistance phenotypes. Using pathway analysis, we found many pathways enriched for each resistance phenotype, but some dominant pathways emerged. The dominant pathways included signaling from the cell surface and cell movement for cisplatin resistance, proteasome regulation and steroid biosynthesis for doxorubicin resistance, and control of translation and oxidative stress for paclitaxel resistance. CONCLUSIONS Ovarian cancer cells develop drug resistance through different pathways depending on the drug used in the generation of chemoresistance. A better understanding of these mechanisms may lead to the development of novel strategies to circumvent the problem of drug resistance.
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Affiliation(s)
- Cheryl A Sherman-Baust
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, Baltimore MD 21224, USA
| | - Kevin G Becker
- Research Resource Branch, National Institute on Aging, Baltimore MD 21224, USA
| | - William H Wood III
- Research Resource Branch, National Institute on Aging, Baltimore MD 21224, USA
| | - Yongqing Zhang
- Research Resource Branch, National Institute on Aging, Baltimore MD 21224, USA
| | - Patrice J Morin
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, Baltimore MD 21224, USA
- Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, MD 21287, USA
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Claudin-7 is frequently overexpressed in ovarian cancer and promotes invasion. PLoS One 2011; 6:e22119. [PMID: 21789222 PMCID: PMC3137611 DOI: 10.1371/journal.pone.0022119] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 06/16/2011] [Indexed: 12/14/2022] Open
Abstract
Background Claudins are tight junction proteins that are involved in tight junction formation and function. Previous studies have shown that claudin-7 is frequently upregulated in epithelial ovarian cancer (EOC) along with claudin-3 and claudin-4. Here, we investigate in detail the expression patterns of claudin-7, as well as its possible functions in EOC. Methodology/Principal Findings A total of 95 ovarian tissue samples (7 normal ovarian tissues, 65 serous carcinomas, 11 clear cell carcinomas, 8 endometrioid carcinomas and 4 mucinous carcinomas) were studied for claudin-7 expression. In real-time RT-PCR analysis, the gene for claudin-7, CLDN7, was found to be upregulated in all the tumor tissue samples studied. Similarly, immunohistochemical analysis and western blotting showed that claudin-7 protein was significantly overexpressed in the vast majority of EOCs. Small interfering RNA-mediated knockdown of claudin-7 in ovarian cancer cells led to significant changes in gene expression as measured by microarrays and validated by RT-PCR and immunoblotting. Analyses of the genes differentially expressed revealed that the genes altered in response to claudin-7 knockdown were associated with pathways implicated in various molecular and cellular functions such as cell cycle, cellular growth and proliferation, cell death, development, and cell movement. Through functional experiments in vitro, we found that both migration and invasion were altered in cells where CLDN7 had been knocked down or overexpressed. Interestingly, claudin-7 expression was associated with a net increase in invasion, but also with a decrease in migration. Conclusion/Significance Our work shows that claudin-7 is significantly upregulated in EOC and that it may be functionally involved in ovarian carcinoma invasion. CLDN7 may therefore represent potential marker for ovarian cancer detection and a target for therapy.
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Yang JL, Sykora P, Wilson DM, Mattson MP, Bohr VA. The excitatory neurotransmitter glutamate stimulates DNA repair to increase neuronal resiliency. Mech Ageing Dev 2011; 132:405-11. [PMID: 21729715 DOI: 10.1016/j.mad.2011.06.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Revised: 05/27/2011] [Accepted: 06/20/2011] [Indexed: 10/18/2022]
Abstract
Glutamate is the most abundant excitatory neurotransmitter in the vertebrate central nervous system and plays an important role in synaptic plasticity required for learning and memory. Activation of glutamate ionotropic receptors promptly triggers membrane depolarization and Ca(2+) influx, resulting in the activation of several different protein kinases and transcription factors. For example, glutamate-mediated Ca(2+) influx activates Ca(2+)/calmodulin-dependent kinase, protein kinase C, and mitogen activated protein kinases resulting in activation of transcription factors such as cyclic AMP response element binding protein (CREB). Abnormally prolonged exposure to glutamate causes neuronal injury, and such "excitotoxicity" has been implicated in many acute and chronic diseases including ischemic stroke, epilepsy, amyotrophic lateral sclerosis, Alzheimer's, Huntington's and Parkinson's diseases. Interestingly, although glutamate-induced Ca(2+) influx can cause DNA damage by a mitochondrial reactive oxygen species-mediated mechanism, the Ca(2+) simultaneously activates CREB, resulting in up-regulation of the DNA repair and redox protein apurinic/apyrimidinic endonuclease 1. Here, we review connections between physiological or aberrant glutamate receptor activation, Ca(2+)-mediated signaling, oxidative DNA damage and repair efficiency, and neuronal vulnerability. We conclude that glutamate signaling involves an adaptive cellular stress response pathway that enhances DNA repair capability, thereby protecting neurons against injury and disease.
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Affiliation(s)
- Jenq-Lin Yang
- Laboratory of Molecular Gerontology, National Institute on Aging Intramural Research Program, Baltimore, MD, USA.
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Disrupted energy metabolism and neuronal circuit dysfunction in cognitive impairment and Alzheimer's disease. Lancet Neurol 2010; 10:187-98. [PMID: 21147038 DOI: 10.1016/s1474-4422(10)70277-5] [Citation(s) in RCA: 393] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Epidemiological, neuropathological, and functional neuroimaging evidence implicates global and regional disruptions in brain metabolism and energetics in the pathogenesis of cognitive impairment. Nerve cell microcircuits are modified by excitatory and inhibitory synaptic activity and neurotrophic factors. Ageing and Alzheimer's disease cause perturbations in cellular energy metabolism, level of excitation or inhibition, and neurotrophic factor release, which overwhelm compensatory mechanisms and result in dysfunction of neuronal microcircuits and brain networks. A prolonged positive energy balance impairs the ability of neurons to adapt to oxidative and metabolic stress. Results from experimental studies in animals show how disruptions caused by chronic positive energy balance, such as diabetes, lead to accelerated cognitive ageing and Alzheimer's disease. Therapeutic interventions to allay cognitive dysfunction that target energy metabolism and adaptive stress responses (such as neurotrophin signalling) have been effective in animal models and in preliminary studies in humans.
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32
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Camandola S, Mattson MP. Aberrant subcellular neuronal calcium regulation in aging and Alzheimer's disease. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1813:965-73. [PMID: 20950656 DOI: 10.1016/j.bbamcr.2010.10.005] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 10/01/2010] [Accepted: 10/03/2010] [Indexed: 02/06/2023]
Abstract
In this mini-review/opinion article we describe evidence that multiple cellular and molecular alterations in Alzheimer's disease (AD) pathogenesis involve perturbed cellular calcium regulation, and that alterations in synaptic calcium handling may be early and pivotal events in the disease process. With advancing age neurons encounter increased oxidative stress and impaired energy metabolism, which compromise the function of proteins that control membrane excitability and subcellular calcium dynamics. Altered proteolytic cleavage of the β-amyloid precursor protein (APP) in response to the aging process in combination with genetic and environmental factors results in the production and accumulation of neurotoxic forms of amyloid β-peptide (Aβ). Aβ undergoes a self-aggregation process and concomitantly generates reactive oxygen species that can trigger membrane-associated oxidative stress which, in turn, impairs the functions of ion-motive ATPases and glutamate and glucose transporters thereby rendering neurons vulnerable to excitotoxicity and apoptosis. Mutations in presenilin-1 that cause early-onset AD increase Aβ production, but also result in an abnormal increase in the size of endoplasmic reticulum calcium stores. Some of the events in the neurodegenerative cascade can be counteracted in animal models by manipulations that stabilize neuronal calcium homeostasis including dietary energy restriction, agonists of glucagon-like peptide 1 receptors and drugs that activate mitochondrial potassium channels. Emerging knowledge of the actions of calcium upstream and downstream of Aβ provides opportunities to develop novel preventative and therapeutic interventions for AD. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.
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Affiliation(s)
- Simonetta Camandola
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, MD, USA
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