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Lee YY, Han JI, Lee KE, Cho S, Suh EC. Neuroprotective effect of dexmedetomidine on autophagy in mice administered intracerebroventricular injections of Aβ 25-35. Front Pharmacol 2023; 14:1184776. [PMID: 37663257 PMCID: PMC10469611 DOI: 10.3389/fphar.2023.1184776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 08/08/2023] [Indexed: 09/05/2023] Open
Abstract
Alzheimer's disease (AD), one of the most prevalent neurodegenerative diseases is associated with pathological autophagy-lysosomal pathway dysfunction. Dexmedetomidine (Dex) has been suggested as an adjuvant to general anesthesia with advantages in reducing the incidence of postoperative cognitive dysfunction in Dex-treated patients with AD and older individuals. Several studies reported that Dex improved memory; however, evidence on the effects of Dex on neuronal autophagy dysfunction in the AD model is lacking. We hypothesized that Dex administration would have neuroprotective effects by improving pathological autophagy dysfunction in mice that received an intracerebroventricular (i.c.v.) injection of amyloid β-protein fragment 25-35 (Aβ25-35) and in an autophagy-deficient cellular model. In the Y-maze test, Dex reversed the decreased activity of Aβ25-35 mice. Additionally, it restored the levels of two memory-related proteins, phosphorylated Ca2+/calmodulin-dependent protein kinase II (p-CaMKII) and postsynaptic density-95 (PSD-95) in Aβ25-35 mice and organotypic hippocampal slice culture (OHSC) with Aβ25-35. Dex administration also resulted in decreased expression of the autophagy-related microtubule-associated proteins light chain 3-II (LC3-II), p62, lysosome-associated membrane protein2 (LAMP2), and cathepsin D in Aβ25-35 mice and OHSC with Aβ25-35. Increased numbers of co-localized puncta of LC3-LAMP2 or LC3-cathepsin D, along with dissociated LC3-p62 immunoreactivity following Dex treatment, were observed. These findings were consistent with the results of western blots and the transformation of double-membrane autophagosomes into single-membraned autolysosomes in ultrastructures. It was evident that Dex treatment alleviated impaired autolysosome formation in Aβ mice. Our study demonstrated the improvement of memory impairment caused by Dex and its neuroprotective mechanism by investigating the role of the autophagy-lysosomal pathway in a murine Aβ25-35 model. These findings suggest that Dex could be used as a potential neuroprotective adjuvant in general anesthesia to prevent cognitive decline.
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Affiliation(s)
- Youn Young Lee
- Department of Anesthesiology and Pain Medicine, Ewha Womans University Seoul Hospital, Seoul, Republic of Korea
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Jong In Han
- Department of Anesthesiology and Pain Medicine, Ewha Womans University Seoul Hospital, Seoul, Republic of Korea
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Kyung Eun Lee
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Sooyoung Cho
- Department of Anesthesiology and Pain Medicine, Ewha Womans University Seoul Hospital, Seoul, Republic of Korea
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Eun Cheng Suh
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
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Mann B, Zhang X, Bell N, Adefolaju A, Thang M, Dasari R, Kanchi K, Valdivia A, Yang Y, Buckley A, Lettry V, Quinsey C, Rauf Y, Kram D, Cassidy N, Vaziri C, Corcoran DL, Rego S, Jiang Y, Graves LM, Dunn D, Floyd S, Baldwin A, Hingtgen S, Satterlee AB. A living ex vivo platform for functional, personalized brain cancer diagnosis. Cell Rep Med 2023; 4:101042. [PMID: 37192626 PMCID: PMC10313921 DOI: 10.1016/j.xcrm.2023.101042] [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: 12/16/2022] [Revised: 03/08/2023] [Accepted: 04/19/2023] [Indexed: 05/18/2023]
Abstract
Functional precision medicine platforms are emerging as promising strategies to improve pre-clinical drug testing and guide clinical decisions. We have developed an organotypic brain slice culture (OBSC)-based platform and multi-parametric algorithm that enable rapid engraftment, treatment, and analysis of uncultured patient brain tumor tissue and patient-derived cell lines. The platform has supported engraftment of every patient tumor tested to this point: high- and low-grade adult and pediatric tumor tissue rapidly establishes on OBSCs among endogenous astrocytes and microglia while maintaining the tumor's original DNA profile. Our algorithm calculates dose-response relationships of both tumor kill and OBSC toxicity, generating summarized drug sensitivity scores on the basis of therapeutic window and allowing us to normalize response profiles across a panel of U.S. Food and Drug Administration (FDA)-approved and exploratory agents. Summarized patient tumor scores after OBSC treatment show positive associations to clinical outcomes, suggesting that the OBSC platform can provide rapid, accurate, functional testing to ultimately guide patient care.
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Affiliation(s)
- Breanna Mann
- Eshelman School of Pharmacy, Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Xiaopei Zhang
- Eshelman School of Pharmacy, Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Noah Bell
- Eshelman School of Pharmacy, Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Adebimpe Adefolaju
- Eshelman Institute for Innovation, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Morrent Thang
- Department of Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Rajaneekar Dasari
- Eshelman Institute for Innovation, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Krishna Kanchi
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Alain Valdivia
- Eshelman School of Pharmacy, Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Yang Yang
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Andrew Buckley
- Eshelman School of Pharmacy, Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Vivien Lettry
- Eshelman School of Pharmacy, Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Carolyn Quinsey
- Department of Neurosurgery, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Yasmeen Rauf
- Department of Neurosurgery, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Neurology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - David Kram
- Division of Pediatric Hematology-Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Noah Cassidy
- School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Cyrus Vaziri
- Department of Pathology and Laboratory Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - David L Corcoran
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Stephen Rego
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Yuchao Jiang
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Lee M Graves
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Denise Dunn
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA
| | - Scott Floyd
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA
| | - Albert Baldwin
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Shawn Hingtgen
- Eshelman School of Pharmacy, Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Andrew B Satterlee
- Eshelman School of Pharmacy, Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Eshelman Institute for Innovation, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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3
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Canet G, Zussy C, Hernandez C, Maurice T, Desrumaux C, Givalois L. The pathomimetic oAβ25–35 model of Alzheimer's disease: Potential for screening of new therapeutic agents. Pharmacol Ther 2023; 245:108398. [PMID: 37001735 DOI: 10.1016/j.pharmthera.2023.108398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 03/27/2023] [Indexed: 03/31/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia in the elderly, currently affecting more than 40 million people worldwide. The two main histopathological hallmarks of AD were identified in the 1980s: senile plaques (composed of aggregated amyloid-β (Aβ) peptides) and neurofibrillary tangles (composed of hyperphosphorylated tau protein). In the human brain, both Aβ and tau show aggregation into soluble and insoluble oligomers. Soluble oligomers of Aβ include their most predominant forms - Aβ1-40 and Aβ1-42 - as well as shorter peptides such as Aβ25-35 or Aβ25-35/40. Most animal models of AD have been developed using transgenesis, based on identified human mutations. However, these familial forms of AD represent less than 1% of AD cases. In this context, the idea emerged in the 1990s to directly inject the Aβ25-35 fragment into the rodent brain to develop an acute model of AD that could mimic the disease's sporadic forms (99% of all cases). This review aims to: (1) summarize the biological activity of Aβ25-35, focusing on its impact on the main structural and functional alterations observed in AD (cognitive deficits, APP misprocessing, tau system dysfunction, neuroinflammation, oxidative stress, cholinergic and glutamatergic alterations, HPA axis dysregulation, synaptic deficits and cell death); and (2) confirm the interest of this pathomimetic model in AD research, as it has helped identify and characterize many molecules (marketed, in clinical development, and in preclinical testing), and to the development of alternative approaches for AD prevention and therapy. Today, the Aβ25-35 model appears as a first-intent choice model to rapidly screen the symptomatic or neuroprotective potencies of new compounds, chemical series, or innovative therapeutic strategies.
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Humpel C. Organotypic Brain Slices of ADULT Transgenic Mice: A Tool to Study Alzheimer's Disease. Curr Alzheimer Res 2020; 16:172-181. [PMID: 30543174 DOI: 10.2174/1567205016666181212153138] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/23/2018] [Accepted: 11/29/2018] [Indexed: 01/21/2023]
Abstract
Transgenic mice have been extensively used to study the Alzheimer pathology. In order to reduce, refine and replace (3Rs) the number of animals, ex vivo cultures are used and optimized. Organotypic brain slices are the most potent ex vivo slice culture models, keeping the 3-dimensional structure of the brain and being closest to the in vivo situation. Organotypic brain slice cultures have been used for many decades but were mainly prepared from postnatal (day 8-10) old rats or mice. More recent work (including our lab) now aims to culture organotypic brain slices from adult mice including transgenic mice. Especially in Alzheimer´s disease research, brain slices from adult transgenic mice will be useful to study beta-amyloid plaques, tau pathology and glial activation. This review will summarize the studies using organotypic brain slice cultures from adult mice to mimic Alzheimer's disease and will highlight advantages and also pitfalls using this technique.
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Affiliation(s)
- Christian Humpel
- Laboratory of Psychiatry and Experimental Alzheimer's Research, Medical University of Innsbruck, Innsbruck, Austria
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Antiamnesic effects of tofisopam against scopolamine-induced cognitive impairments in rats. Pharmacol Biochem Behav 2020; 190:172858. [PMID: 31981560 DOI: 10.1016/j.pbb.2020.172858] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 01/13/2020] [Accepted: 01/21/2020] [Indexed: 01/19/2023]
Abstract
In this study, we investigated the potential therapeutic effects of tofisopam, a 2,3-benzodiazepine derivative anxiolytic, on cognitive deficits in rats with scopolamine-induced amnesia. Cognitive performance of the rats was investigated by using the Morris water maze and passive avoidance tests. Changes in motor activity were assessed by using the activity cage and Rota-rod tests and then morphological changes in the hippocampus were assessed via immunohistochemical stainings. The results indicated that scopolamine impaired learning and memory parameters in rats. Worsened cognitive performance, neuronal loss, and decreased hippocampal synaptophysin, Ki-67, and glial fibrillary acidic protein density were observed. Tofisopam administration at a dose of 50 mg/kg for seven days improved the impaired cognitive performance, enhanced the attenuated synaptic transmission in the hippocampus, increased proliferation in subgranular zones, and improved the decrease in astrocytes in amnesic rats. These findings point out the anti-amnesic effects of tofisopam with concomitant improvements in the hippocampal synaptogenesis, neurogenesis, and glial plasticity, for the first time. Presented beneficial effects of tofisopam on cognitive dysfunctions may have a notable clinical value considering the fact that one of the most important side effects of 1,4-benzodiazepines, which are classical anxiolytic drugs, is amnesia. However, these preclinical results need to be confirmed with further clinical studies, first.
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Richter M, Vidovic N, Biber K, Dolga A, Culmsee C, Dodel R. The neuroprotective role of microglial cells against amyloid beta-mediated toxicity in organotypic hippocampal slice cultures. Brain Pathol 2020; 30:589-602. [PMID: 31769564 PMCID: PMC8018096 DOI: 10.1111/bpa.12807] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 11/18/2019] [Indexed: 02/02/2023] Open
Abstract
During Alzheimer's disease (AD) progression, microglial cells play complex roles and have potentially detrimental as well as beneficial effects. The use of appropriate model systems is essential for characterizing and understanding the roles of microglia in AD pathology. Here, we used organotypic hippocampal slice cultures (OHSCs) to investigate the impact of microglia on amyloid beta (Aβ)-mediated toxicity. Neurons in OHSCs containing microglia were not vulnerable to cell death after 7 days of repeated treatment with Aβ1-42 oligomer-enriched preparations. However, when clodronate was used to remove microglia, treatment with Aβ1-42 resulted in significant neuronal death. Further investigations indicated signs of endoplasmic reticulum stress and caspase activation after Aβ1-42 challenge only when microglia were absent. Interestingly, microglia provided protection without displaying any classic signs of activation, such as an amoeboid morphology or the release of pro-inflammatory mediators (e.g., IL-6, TNF-α, NO). Furthermore, depleting microglia or inhibiting microglial uptake mechanisms resulted in significant more Aβ deposition compared to that observed in OHSCs containing functional microglia, suggesting that microglia efficiently cleared Aβ. Because inhibiting microglial uptake increased neuronal cell death, the ability of microglia to engulf Aβ is thought to contribute to its protective properties. Our study argues for a beneficial role of functional ramified microglia whereby they act against the accumulation of neurotoxic forms of Aβ and support neuronal resilience in an in situ model of AD pathology.
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Affiliation(s)
- Maren Richter
- Department of Neurology, Philipps-University Marburg, Marburg, Germany.,Institute for Pharmacology and Clinical Pharmacy, Philipps-University Marburg, Marburg, Germany
| | - Natascha Vidovic
- Department of Neurology, Philipps-University Marburg, Marburg, Germany.,Chair of Geriatric Medicine, University Duisburg-Essen, Essen, Germany
| | - Knut Biber
- Molecular Psychiatry, Psychiatric Hospital, University of Freiburg, Freiburg, Germany.,Department of Neuroscience, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Amalia Dolga
- Institute for Pharmacology and Clinical Pharmacy, Philipps-University Marburg, Marburg, Germany.,Department of Molecular Pharmacology, Groningen Research Institute of Pharmacy, Faculty of Science and Engineering, Groningen, the Netherlands
| | - Carsten Culmsee
- Institute for Pharmacology and Clinical Pharmacy, Philipps-University Marburg, Marburg, Germany
| | - Richard Dodel
- Department of Neurology, Philipps-University Marburg, Marburg, Germany.,Chair of Geriatric Medicine, University Duisburg-Essen, Essen, Germany
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7
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Chen L, Yan Y, Chen T, Zhang L, Gao X, Du C, Du H. Forsythiaside prevents β-amyloid-induced hippocampal slice injury by upregulating 2-arachidonoylglycerol via cannabinoid receptor 1-dependent NF-κB pathway. Neurochem Int 2019; 125:57-66. [DOI: 10.1016/j.neuint.2019.02.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 01/30/2019] [Accepted: 02/12/2019] [Indexed: 01/02/2023]
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8
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Beccari S, Diaz‐Aparicio I, Sierra A. Quantifying Microglial Phagocytosis of Apoptotic Cells in the Brain in Health and Disease. ACTA ACUST UNITED AC 2018; 122:e49. [DOI: 10.1002/cpim.49] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Sol Beccari
- Achucarro Basque Center for Neuroscience Leioa Bizkaia Spain
- University of the Basque Country UPV/EHU Leioa Bizkaia Spain
| | - Irune Diaz‐Aparicio
- Achucarro Basque Center for Neuroscience Leioa Bizkaia Spain
- University of the Basque Country UPV/EHU Leioa Bizkaia Spain
| | - Amanda Sierra
- Achucarro Basque Center for Neuroscience Leioa Bizkaia Spain
- University of the Basque Country UPV/EHU Leioa Bizkaia Spain
- Ikerbasque Foundation Bilbao Bizkaia Spain
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Exposing primary rat retina cell cultures to γ-rays: An in vitro model for evaluating radiation responses. Exp Eye Res 2017; 166:21-28. [PMID: 28958589 DOI: 10.1016/j.exer.2017.09.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 09/14/2017] [Accepted: 09/19/2017] [Indexed: 11/22/2022]
Abstract
Retinal tissue can receive incidental γ-rays exposure during radiotherapy either of tumors of the eye and optic nerve or of head-and-neck tumors, and during medical diagnostic procedures. Healthy retina is therefore at risk of suffering radiation-related side effects and the knowledge of pathophysiological response of retinal cells to ionizing radiations could be useful to design possible strategies of prevention and management of radiotoxicity. In this study, we have exploited an in vitro model (primary rat retinal cell culture) to study an array of biological effects induced on retinal neurons by γ-rays. Most of the different cell types present in retinal tissue - either of the neuronal or glial lineages - are preserved in primary rat retinal cultures. Similar to the retina in situ, neuronal cells undergo in vitro a maturational development shown by the formation of polarized neuritic trees and operating synapses. Since 2 Gy is the incidental dose received by the healthy retina per fraction when the standard treatment is delivered to the brain, retina cell cultures have been exposed to 1 or 2 Gy of γ-rays at different level of neuronal differentiation in vitro: days in vitro (DIV)2 or DIV8. At DIV9, retinal cultures were analyzed in terms of viability, apoptosis and characterized by immunocytochemistry to identify alterations in neuronal differentiation. After irradiation at DIV2, MTT assay revealed an evident loss of cell viability and βIII-tubulin immunostaining highlighted a marked neuritic damage, indicating that survived neurons showed an impaired differentiation. Differentiated cultures (DIV8) appeared to be more resistant with respect to undifferentiated, DIV2 cultures, both in terms of cell viability and differentiation. Apoptosis evaluated with TUNEL assay showed that irradiation at both DIV2 and DIV8 induced a significant increase in the apoptotic rate. To further investigate the effects of γ-rays on retinal neurons, we evaluated the expression of synaptic proteins, such as SNAP25 and synaptophysin. WB and immunofluorescence analysis showed an altered expression of these proteins in particular when cultures were irradiated at DIV2. To evaluate the effect of γ-rays on photoreceptors, we studied the expression of rhodopsin in WB analysis and immunofluorescence. Our results confirm data from the literature that differentiated photoreceptors appear to be more resistant to irradiation respect to other retinal cell types present in cultures. The results obtained suggest that γ-rays exposure of primary retinal cultures may contribute to shed further light on the mechanisms involved in γ-radiation-induced neurodegeneration.
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Miller AP, Shah AS, Aperi BV, Kurpad SN, Stemper BD, Glavaski-Joksimovic A. Acute death of astrocytes in blast-exposed rat organotypic hippocampal slice cultures. PLoS One 2017; 12:e0173167. [PMID: 28264063 PMCID: PMC5338800 DOI: 10.1371/journal.pone.0173167] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 02/16/2017] [Indexed: 01/06/2023] Open
Abstract
Blast traumatic brain injury (bTBI) affects civilians, soldiers, and veterans worldwide and presents significant health concerns. The mechanisms of neurodegeneration following bTBI remain elusive and current therapies are largely ineffective. It is important to better characterize blast-evoked cellular changes and underlying mechanisms in order to develop more effective therapies. In the present study, our group utilized rat organotypic hippocampal slice cultures (OHCs) as an in vitro system to model bTBI. OHCs were exposed to either 138 ± 22 kPa (low) or 273 ± 23 kPa (high) overpressures using an open-ended helium-driven shock tube, or were assigned to sham control group. At 2 hours (h) following injury, we have characterized the astrocytic response to a blast overpressure. Immunostaining against the astrocytic marker glial fibrillary acidic protein (GFAP) revealed acute shearing and morphological changes in astrocytes, including clasmatodendrosis. Moreover, overlap of GFAP immunostaining and propidium iodide (PI) indicated astrocytic death. Quantification of the number of dead astrocytes per counting area in the hippocampal cornu Ammonis 1 region (CA1), demonstrated a significant increase in dead astrocytes in the low- and high-blast, compared to sham control OHCs. However only a small number of GFAP-expressing astrocytes were co-labeled with the apoptotic marker Annexin V, suggesting necrosis as the primary type of cell death in the acute phase following blast exposure. Moreover, western blot analyses revealed calpain mediated breakdown of GFAP. The dextran exclusion additionally indicated membrane disruption as a potential mechanism of acute astrocytic death. Furthermore, although blast exposure did not evoke significant changes in glutamate transporter 1 (GLT-1) expression, loss of GLT-1-expressing astrocytes suggests dysregulation of glutamate uptake following injury. Our data illustrate the profound effect of blast overpressure on astrocytes in OHCs at 2 h following injury and suggest increased calpain activity and membrane disruption as potential underlying mechanisms.
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Affiliation(s)
- Anna P. Miller
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Clement J. Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin, United States of America
| | - Alok S. Shah
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Clement J. Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin, United States of America
| | - Brandy V. Aperi
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Clement J. Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin, United States of America
| | - Shekar N. Kurpad
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Clement J. Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin, United States of America
| | - Brian D. Stemper
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Clement J. Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin, United States of America
| | - Aleksandra Glavaski-Joksimovic
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- Clement J. Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin, United States of America
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Humpel C. Organotypic brain slice cultures: A review. Neuroscience 2015; 305:86-98. [PMID: 26254240 PMCID: PMC4699268 DOI: 10.1016/j.neuroscience.2015.07.086] [Citation(s) in RCA: 271] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 07/24/2015] [Accepted: 07/31/2015] [Indexed: 12/27/2022]
Abstract
In vitro cell cultures are an important tool for obtaining insights into cellular processes in an isolated system and a supplement to in vivo animal experiments. While primary dissociated cultures permit a single homogeneous cell population to be studied, there is a clear need to explore the function of brain cells in a three-dimensional system where the main architecture of the cells is preserved. Thus, organotypic brain slice cultures have proven to be very useful in investigating cellular and molecular processes of the brain in vitro. This review summarizes (1) the historical development of organotypic brain slices focusing on the membrane technology, (2) methodological aspects regarding culturing procedures, age of donors or media, (3) whether the cholinergic neurons serve as a model of neurodegeneration in Alzheimer’s disease, (4) or the nigrostriatal dopaminergic neurons as a model of Parkinson’s disease and (5) how the vascular network can be studied, especially with regard to a synthetic blood–brain barrier. This review will also highlight some limits of the model and give an outlook on future applications.
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Affiliation(s)
- C Humpel
- Laboratory of Psychiatry and Experimental Alzheimer's Research, Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria.
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12
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Tran L, Ha-Duong T. Exploring the Alzheimer amyloid-β peptide conformational ensemble: A review of molecular dynamics approaches. Peptides 2015; 69:86-91. [PMID: 25908410 DOI: 10.1016/j.peptides.2015.04.009] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 04/02/2015] [Accepted: 04/07/2015] [Indexed: 12/22/2022]
Abstract
Alzheimer's disease is one of the most common dementia among elderly worldwide. There is no therapeutic drugs until now to treat effectively this disease. One main reason is due to the poorly understood mechanism of Aβ peptide aggregation, which plays a crucial role in the development of Alzheimer's disease. It remains challenging to experimentally or theoretically characterize the secondary and tertiary structures of the Aβ monomer because of its high flexibility and aggregation propensity, and its conformations that lead to the aggregation are not fully identified. In this review, we highlight various structural ensembles of Aβ peptide revealed and characterized by computational approaches in order to find converging structures of Aβ monomer. Understanding how Aβ peptide forms transiently stable structures prior to aggregation will contribute to the design of new therapeutic molecules against the Alzheimer's disease.
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Affiliation(s)
- Linh Tran
- BioCIS, UMR CNRS 8076, LabEx LERMIT, Faculty of Pharmacy, University Paris Sud, 5 Rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France
| | - Tâp Ha-Duong
- BioCIS, UMR CNRS 8076, LabEx LERMIT, Faculty of Pharmacy, University Paris Sud, 5 Rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France.
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13
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Abnormal Expression of Synaptophysin, SNAP-25, and Synaptotagmin 1 in the Hippocampus of Kainic Acid-Exposed Rats with Behavioral Deficits. Cell Mol Neurobiol 2014; 34:813-24. [DOI: 10.1007/s10571-014-0068-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 02/27/2014] [Indexed: 12/29/2022]
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14
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Hoppe JB, Frozza RL, Pires ENS, Meneghetti AB, Salbego C. The curry spice curcumin attenuates beta-amyloid-induced toxicity through beta-catenin and PI3K signaling in rat organotypic hippocampal slice culture. Neurol Res 2013; 35:857-66. [DOI: 10.1179/1743132813y.0000000225] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Juliana Bender Hoppe
- Laboratory of Neuroprotection and Cell SignalingDepartment of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Rudimar Luiz Frozza
- Laboratory of Neurodegenerative DiseasesInstitute of Medical Biochemestry, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Elisa Nicoloso Simões Pires
- Laboratory of Neuroprotection and Cell SignalingDepartment of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - André Bevilacqua Meneghetti
- Laboratory of Neuroprotection and Cell SignalingDepartment of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Christianne Salbego
- Laboratory of Neuroprotection and Cell SignalingDepartment of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
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15
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Suh EC, Jung YJ, Kim YA, Park EM, Lee SJ, Lee KE. Knockout of Toll-like receptor 2 attenuates Aβ25-35-induced neurotoxicity in organotypic hippocampal slice cultures. Neurochem Int 2013; 63:818-25. [PMID: 24161618 DOI: 10.1016/j.neuint.2013.10.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 09/13/2013] [Accepted: 10/15/2013] [Indexed: 12/21/2022]
Abstract
Toll-like receptors (TLRs), which have been implicated in various neuroinflammatory responses, are thought to act in defense mechanisms by inhibiting neuronal cell death in Alzheimer's disease. In this study, we evaluated the effects of TLR2 on amyloid beta peptide 25-35 (Aβ25-35)-induced neuronal cell death, synaptic dysfunction, and microglial activation in organotypic hippocampal slice cultures (OHSCs) from wild-type (WT) C57BL/6 mice and TLR2-knockout (KO) mice. In WT mice, Aβ25-35 induced β-amyloid aggregation and surrounding TLR2 expression. And, propidium iodide (PI) uptake, which is a measure of cell death, increased in a dose-dependent manner in slices with Aβ25-35 treatment. In the Aβ25-35-treated TLR2-KO OHSCs, the PI uptake was significantly attenuated to the control level, indicating that the cells were less susceptible to Aβ25-35-induced neuronal toxicity. In the ultrastructural analysis, nuclear shrinkage, slightly swollen mitochondria, and degraded organelles were detected in the Aβ25-35-treated slices from WT mice but not in the Aβ25-35-treated slices from TLR2-KO, suggesting the resistance of TLR2-KO to Aβ25-35-induced neurotoxicity. In Aβ25-35-treated OHSCs of WT mice, the levels of phosphorylated tau were increased and the levels of synaptophysin were decreased in a dose-dependent manner, but they were not changed in OHSCs of TLR2-KO mice. In WT mice, Aβ25-35 increased total protein level and immunoreactivity of Iba-1, which was colocalized with TLR2. However, there were no significant changes in the slices of Aβ25-35-treated TLR2-KO mice. These results suggested that TLR2 may play a role in Aβ25-35-induced neuronal cell loss and synaptic dysfunction through the activation of microglia in OHSCs.
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Affiliation(s)
- Eun Cheng Suh
- Department of Pharmacology and Ewha Medical Research Institute, School of Medicine, Ewha Womans University, Seoul, South Korea
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16
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Hoppe JB, Haag M, Whalley BJ, Salbego CG, Cimarosti H. Curcumin protects organotypic hippocampal slice cultures from Aβ1-42-induced synaptic toxicity. Toxicol In Vitro 2013; 27:2325-30. [PMID: 24134851 DOI: 10.1016/j.tiv.2013.10.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 09/25/2013] [Accepted: 10/03/2013] [Indexed: 11/28/2022]
Abstract
Increasing evidence demonstrates that beta-amyloid (Aβ) is toxic to synapses, resulting in the progressive dismantling of neuronal circuits. Counteract the synaptotoxic effects of Aβ could be particularly relevant for providing effective treatments for Alzheimer's disease (AD). Curcumin was recently reported to improve learning and memory in animal models of AD. Little is currently known about the specific mechanisms by which Aβ affects neuronal excitability and curcumin ameliorates synaptic transmission in the hippocampus. Organotypic hippocampal slice cultures exposed to Aβ1-42 were used to study the neuroprotective effects of curcumin through a spectral analysis of multi-electrode array (MEA) recordings of spontaneous neuronal activity. Curcumin counteracted both deleterious effects of Aβ; the initial synaptic dysfunction and the later neuronal death. The analysis of MEA recordings of spontaneous neuronal activity showed an attenuation of signal propagation induced by Aβ before cell death and curcumin-induced alterations to local field potential (LFP) phase coherence. Curcumin-mediated attenuation of Aβ-induced synaptic dysfunction involved regulation of synaptic proteins, namely phospho-CaMKII and phospho-synapsin I. Taken together, our results expand the neuroprotective role of curcumin to a synaptic level. The identification of these mechanisms underlying the effects of curcumin may lead to new targets for future therapies for AD.
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Affiliation(s)
- Juliana Bender Hoppe
- Reading School of Pharmacy, University of Reading, Whiteknights, Reading RG6 6UB, UK; Laboratory of Neuroprotection and Cell Signalling, Department of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, RS 90035-003, Brazil.
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17
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Corbett NJ, Gabbott PL, Klementiev B, Davies HA, Colyer FM, Novikova T, Stewart MG. Amyloid-beta induced CA1 pyramidal cell loss in young adult rats is alleviated by systemic treatment with FGL, a neural cell adhesion molecule-derived mimetic peptide. PLoS One 2013; 8:e71479. [PMID: 23951173 PMCID: PMC3739720 DOI: 10.1371/journal.pone.0071479] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 06/29/2013] [Indexed: 12/24/2022] Open
Abstract
Increased levels of neurotoxic amyloid-beta in the brain are a prominent feature of Alzheimer's disease. FG-Loop (FGL), a neural cell adhesion molecule-derived peptide that corresponds to its second fibronectin type III module, has been shown to provide neuroprotection against a range of cellular insults. In the present study impairments in social recognition memory were seen 24 days after a 5 mg/15 µl amyloid-beta(25-35) injection into the right lateral ventricle of the young adult rat brain. This impairment was prevented if the animal was given a systemic treatment of FGL. Unbiased stereology was used to investigate the ability of FGL to alleviate the deleterious effects on CA1 pyramidal cells of the amyloid-beta(25-35) injection. NeuN, a neuronal marker (for nuclear staining) was used to identify pyramidal cells, and immunocytochemistry was also used to identify inactive glycogen synthase kinase 3beta (GSK3β) and to determine the effects of amyloid-beta(25-35) and FGL on the activation state of GSK3β, since active GSK3β has been shown to cause a range of AD pathologies. The cognitive deficits were not due to hippocampal atrophy as volume estimations of the entire hippocampus and its regions showed no significant loss, but amyloid-beta caused a 40% loss of pyramidal cells in the dorsal CA1 which was alleviated partially by FGL. However, FGL treatment without amyloid-beta was also found to cause a 40% decrease in CA1 pyramidal cells. The action of FGL may be due to inactivation of GSK3β, as an increased proportion of CA1 pyramidal neurons contained inactive GSK3β after FGL treatment. These data suggest that FGL, although potentially disruptive in non-pathological conditions, can be neuroprotective in disease-like conditions.
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Affiliation(s)
- Nicola J Corbett
- Open University, Department of Life, Health and Chemical Sciences, Milton Keynes, United Kingdom.
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18
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Zhou XW, Zhang Z, Su CF, Lv RH, Zhou X, Cai L, Wang CY, Yan L, Zhang W, Luo HM. Methyl 3,4-dihydroxybenzoate protects primary cortical neurons against Aβ25-35-induced neurotoxicity through mitochondria pathway. J Neurosci Res 2013; 91:1215-25. [DOI: 10.1002/jnr.23235] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 01/06/2013] [Accepted: 03/14/2013] [Indexed: 11/12/2022]
Affiliation(s)
- Xiao-Wen Zhou
- Department of Pharmacology; School of Medicine, Jinan University; Guangzhou; China
| | - Zheng Zhang
- The First Affiliated Hospital of Jinan University; Guangzhou; China
| | - Chao-Fen Su
- Department of Pharmacology; School of Medicine, Jinan University; Guangzhou; China
| | - Ruo-Hua Lv
- Sinopharm Medicine Holding Guangzhou Co., Ltd.; Guangzhou; China
| | - Xing Zhou
- Department of Pharmacology; School of Medicine, Jinan University; Guangzhou; China
| | - Liang Cai
- Department of Pharmacology; School of Medicine, Jinan University; Guangzhou; China
| | - Chen-Yu Wang
- Department of Clinical Medicine; School of Medicine, Jinan University; Guangzhou; China
| | - Li Yan
- Department of Pharmacology; School of Medicine, Jinan University; Guangzhou; China
| | - Wei Zhang
- Department of Pharmacology; School of Medicine, Jinan University; Guangzhou; China
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19
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Changes in the Neurogenesis and Axonal Sprouting in the Organotypic Hippocampal Slice Culture by Aβ 25-35Treatment. Appl Microsc 2012. [DOI: 10.9729/am.2012.42.4.200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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20
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Jung YJ, Suh EC, Lee KE. Oxygen/Glucose Deprivation and Reperfusion Cause Modifications of Postsynaptic Morphology and Activity in the CA3 Area of Organotypic Hippocampal Slice Cultures. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2012; 16:423-9. [PMID: 23269905 PMCID: PMC3526747 DOI: 10.4196/kjpp.2012.16.6.423] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 10/08/2012] [Accepted: 10/20/2012] [Indexed: 12/25/2022]
Abstract
Brain ischemia leads to overstimulation of N-methyl-D-aspartate (NMDA) receptors, referred as excitotoxicity, which mediates neuronal cell death. However, less attention has been paid to changes in synaptic activity and morphology that could have an important impact on cell function and survival following ischemic insult. In this study, we investigated the effects of reperfusion after oxygen/glucose deprivation (OGD) not only upon neuronal cell death, but also on ultrastructural and biochemical characteristics of postsynaptic density (PSD) protein, in the stratum lucidum of the CA3 area in organotypic hippocampal slice cultures. After OGD/reperfusion, neurons were found to be damaged; the organelles such as mitochondria, endoplasmic reticulum, dendrites, and synaptic terminals were swollen; and the PSD became thicker and irregular. Ethanolic phosphotungstic acid staining showed that the density of PSD was significantly decreased, and the thickness and length of the PSD were significantly increased in the OGD/reperfusion group compared to the control. The levels of PSD proteins, including PSD-95, NMDA receptor 1, NMDA receptor 2B, and calcium/calmodulin-dependent protein kinase II, were significantly decreased following OGD/reperfusion. These results suggest that OGD/reperfusion induces significant modifications to PSDs in the CA3 area of organotypic hippocampal slice cultures, both morphologically and biochemically, and this may contribute to neuronal cell death and synaptic dysfunction after OGD/reperfusion.
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Affiliation(s)
- Yeon Joo Jung
- Department of Pharmacology and Ewha Medical Research Institute, Ewha Womans University School of Medicine, Seoul 158-710, Korea
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21
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Kudryashova IV, Onufriev MV, Gulyaeva NV. Structural and functional features of presynaptic afferents and their dependence on caspase-3 activity in rat hippocampal slices. NEUROCHEM J+ 2012. [DOI: 10.1134/s1819712411040106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Kudryashova IV. Structural and functional modifications of presynaptic afferents: Do they correlate with learning mechanisms? NEUROCHEM J+ 2011. [DOI: 10.1134/s181971241104009x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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23
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Yu X, Wang Q, Zheng J. Structural determination of Abeta25-35 micelles by molecular dynamics simulations. Biophys J 2010; 99:666-74. [PMID: 20643087 DOI: 10.1016/j.bpj.2010.05.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Revised: 04/29/2010] [Accepted: 05/03/2010] [Indexed: 10/19/2022] Open
Abstract
Amyloid-beta (Abeta) peptides and other amyloidogenic proteins can form a wide range of soluble oligomers of varied morphologies at the early aggregation stage, and some of these oligomers are biologically relevant to the pathogenesis of Alzheimer's disease. Spherical micelle-like oligomers have been often observed for many different types of amyloids. Here, we report a hybrid computational approach to systematically construct, search, optimize, and rank soluble micelle-like Abeta25-35 structures with different side-chain packings at the atomic level. Simulations reveal for the first time, to our knowledge, that two Abeta micelles with antiparallel peptide organization and distinct surface hydrophobicity display high structural stability. Stable micelles experience a slow secondary structural transition from turn to alpha-helix. Energetic analysis coupled with computational mutagenesis reveals that van der Waals and solvation energies play a more pronounced role in stabilizing the micelles, whereas the electrostatic energies present a stable but minor energetic contribution to peptide assemblies. Modeled Abeta micelles with shapes and dimensions similar to those of experimentally derived spherical structures also provide detailed information about the roles of structural dynamics and transition in the formation of amyloid fibrils. The strong binding affinity of our micelles to antibodies implies that micelles may be a biologically relevant species.
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Affiliation(s)
- Xiang Yu
- Department of Chemical and Biomolecular Engineering, University of Akron, Akron, Ohio, USA
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24
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Hoppe JB, Frozza RL, Horn AP, Comiran RA, Bernardi A, Campos MM, Battastini AMO, Salbego C. Amyloid-beta neurotoxicity in organotypic culture is attenuated by melatonin: involvement of GSK-3beta, tau and neuroinflammation. J Pineal Res 2010; 48:230-238. [PMID: 20136701 DOI: 10.1111/j.1600-079x.2010.00747.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder marked by accumulation of extracellular deposits of amyloid-beta (Abeta) peptide in brain regions that are important for memory and cognition. The buildup of Abeta aggregates in the AD is followed by the formation of intracellular neurofibrillary tangles and activation of neuroinflammatory reactions. The present study investigated whether melatonin possesses a neuroprotective effect against Abeta-induced toxicity. For this purpose, organotypic hippocampal slices were cultured and exposed to 25 microm of Abeta(25-35) in the absence or in the presence of melatonin (25, 50, or 100 microm). In addition, the authors have investigated the involvement of GSK-3beta, tau protein, astroglial, and microglial activation, and cytokine levels in the melatonin protection against Abeta-induced neurotoxicity. Melatonin prevented the cell damage in hippocampus induced by the exposure to Abeta(25-35). In addition, melatonin significantly reduced the activation of GSK-3beta, the phosphorylation of tau protein, the glial activation and the Abeta-induced increase of TNF-alpha and IL-6 levels. On the basis of these findings, we speculate that melatonin may provide an effective therapeutic strategy for AD, by attenuating Abeta-induced phosphorylation of tau protein, and preventing GSK-3beta activation and neuroinflammation.
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Affiliation(s)
- Juliana Bender Hoppe
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, Rio Grande do Sul, Brazil
| | - Rudimar Luiz Frozza
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, Rio Grande do Sul, Brazil
| | - Ana Paula Horn
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, Rio Grande do Sul, Brazil
| | - Ricardo Argenta Comiran
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, Rio Grande do Sul, Brazil
| | - Andressa Bernardi
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, Rio Grande do Sul, Brazil
| | - Maria Martha Campos
- Faculdade de Odontologia e Instituto de Toxicologia, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | | | - Christianne Salbego
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, Rio Grande do Sul, Brazil
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25
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Ardais AP, Viola GG, Costa MS, Nunes F, Behr GA, Klamt F, Moreira JCF, Souza DO, Rocha JBT, Porciúncula LO. Acute Treatment with Diphenyl Diselenide Inhibits Glutamate Uptake into Rat Hippocampal Slices and Modifies Glutamate Transporters, SNAP-25, and GFAP Immunocontent. Toxicol Sci 2009; 113:434-43. [DOI: 10.1093/toxsci/kfp282] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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26
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Zurich M, Monnet-Tschudi F. Contribution of in vitro neurotoxicology studies to the elucidation of neurodegenerative processes. Brain Res Bull 2009; 80:211-6. [DOI: 10.1016/j.brainresbull.2009.06.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2009] [Revised: 06/16/2009] [Accepted: 06/17/2009] [Indexed: 01/26/2023]
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27
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Frozza RL, Horn AP, Hoppe JB, Simão F, Gerhardt D, Comiran RA, Salbego CG. A comparative study of beta-amyloid peptides Abeta1-42 and Abeta25-35 toxicity in organotypic hippocampal slice cultures. Neurochem Res 2008; 34:295-303. [PMID: 18686032 DOI: 10.1007/s11064-008-9776-8] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Accepted: 06/09/2008] [Indexed: 12/28/2022]
Abstract
Accumulation of the neurotoxic amyloid beta-peptide (Abeta) in the brain is a hallmark of Alzheimer's disease (AD). Several synthetic Abeta peptides have been used to study the mechanisms of toxicity. Here, we sought to establish comparability between two commonly used Abeta peptides Abeta1-42 and Abeta25-35 on an in vitro model of Abeta toxicity. For this purpose we used organotypic slice cultures of rat hippocampus and observed that both Abeta peptides caused similar toxic effects regarding to propidium iodide uptake and caspase-3 activation. In addition, we also did not observe any effect of both peptides on Akt and PTEN phosphorylation; otherwise the phosphorylation of GSK-3beta was increased. Although further studies are necessary for understanding mechanisms underlying Abeta peptide toxicity, our results provide strong evidence that Abeta1-42 and the Abeta25-35 peptides induce neural injury in a similar pattern and that Abeta25-35 is a convenient tool for the investigation of neurotoxic mechanisms involved in AD.
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Affiliation(s)
- Rudimar Luiz Frozza
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul - UFRGS, Av. Ramiro Barcelos, 2600 - anexo, Porto Alegre, RS, CEP 90035-003, Brazil
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