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Chen C, Wei J, Ma X, Xia B, Shakir N, Zhang JK, Zhang L, Cui Y, Ferguson D, Qiu S, Bai F. Disrupted Maturation of Prefrontal Layer 5 Neuronal Circuits in an Alzheimer's Mouse Model of Amyloid Deposition. Neurosci Bull 2023; 39:881-892. [PMID: 36152121 PMCID: PMC10264337 DOI: 10.1007/s12264-022-00951-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/18/2022] [Indexed: 11/26/2022] Open
Abstract
Mutations in genes encoding amyloid precursor protein (APP) and presenilins (PSs) cause familial forms of Alzheimer's disease (AD), a neurodegenerative disorder strongly associated with aging. It is currently unknown whether and how AD risks affect early brain development, and to what extent subtle synaptic pathology may occur prior to overt hallmark AD pathology. Transgenic mutant APP/PS1 over-expression mouse lines are key tools for studying the molecular mechanisms of AD pathogenesis. Among these lines, the 5XFAD mice rapidly develop key features of AD pathology and have proven utility in studying amyloid plaque formation and amyloid β (Aβ)-induced neurodegeneration. We reasoned that transgenic mutant APP/PS1 over-expression in 5XFAD mice may lead to neurodevelopmental defects in early cortical neurons, and performed detailed synaptic physiological characterization of layer 5 (L5) neurons from the prefrontal cortex (PFC) of 5XFAD and wild-type littermate controls. L5 PFC neurons from 5XFAD mice show early APP/Aβ immunolabeling. Whole-cell patch-clamp recording at an early post-weaning age (P22-30) revealed functional impairments; although 5XFAD PFC-L5 neurons exhibited similar membrane properties, they were intrinsically less excitable. In addition, these neurons received smaller amplitude and frequency of miniature excitatory synaptic inputs. These functional disturbances were further corroborated by decreased dendritic spine density and spine head volumes that indicated impaired synapse maturation. Slice biotinylation followed by Western blot analysis of PFC-L5 tissue revealed that 5XFAD mice showed reduced synaptic AMPA receptor subunit GluA1 and decreased synaptic NMDA receptor subunit GluN2A. Consistent with this, patch-clamp recording of the evoked L23>L5 synaptic responses revealed a reduced AMPA/NMDA receptor current ratio, and an increased level of AMPAR-lacking silent synapses. These results suggest that transgenic mutant forms of APP/PS1 overexpression in 5XFAD mice leads to early developmental defects of cortical circuits, which could contribute to the age-dependent synaptic pathology and neurodegeneration later in life.
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Affiliation(s)
- Chang Chen
- Department of Neurology, Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, 210008, China
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Jing Wei
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Xiaokuang Ma
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Baomei Xia
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Neha Shakir
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Jessica K Zhang
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Le Zhang
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Yuehua Cui
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Deveroux Ferguson
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Shenfeng Qiu
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA.
| | - Feng Bai
- Department of Neurology, Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, 210008, China.
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2
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Chen C, Ma X, Wei J, Shakir N, Zhang JK, Zhang L, Nehme A, Cui Y, Ferguson D, Bai F, Qiu S. Early impairment of cortical circuit plasticity and connectivity in the 5XFAD Alzheimer's disease mouse model. Transl Psychiatry 2022; 12:371. [PMID: 36075886 PMCID: PMC9458752 DOI: 10.1038/s41398-022-02132-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 08/16/2022] [Accepted: 08/22/2022] [Indexed: 11/09/2022] Open
Abstract
Genetic risk factors for neurodegenerative disorders, such as Alzheimer's disease (AD), are expressed throughout the life span. How these risk factors affect early brain development and function remain largely unclear. Analysis of animal models with high constructive validity for AD, such as the 5xFAD mouse model, may provide insights on potential early neurodevelopmental effects that impinge on adult brain function and age-dependent degeneration. The 5XFAD mouse model over-expresses human amyloid precursor protein (APP) and presenilin 1 (PS1) harboring five familial AD mutations. It is unclear how the expression of these mutant proteins affects early developing brain circuits. We found that the prefrontal cortex (PFC) layer 5 (L5) neurons in 5XFAD mice exhibit transgenic APP overloading at an early post-weaning age. Impaired synaptic plasticity (long-term potentiation, LTP) was seen at 6-8 weeks age in L5 PFC circuit, which was correlated with increased intracellular APP. APP overloading was also seen in L5 pyramidal neurons in the primary visual cortex (V1) during the critical period of plasticity (4-5 weeks age). Whole-cell patch clamp recording in V1 brain slices revealed reduced intrinsic excitability of L5 neurons in 5XFAD mice, along with decreased spontaneous miniature excitatory and inhibitory inputs. Functional circuit mapping using laser scanning photostimulation (LSPS) combined with glutamate uncaging uncovered reduced excitatory synaptic connectivity onto L5 neurons in V1, and a more pronounced reduction in inhibitory connectivity, indicative of altered excitation and inhibition during VC critical period. Lastly, in vivo single-unit recording in V1 confirmed that monocular visual deprivation-induced ocular dominance plasticity during critical period was impaired in 5XFAD mice. Our study reveals plasticity deficits across multiple cortical regions and indicates altered early cortical circuit developmental trajectory as a result of mutant APP/PS1 over-expression.
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Affiliation(s)
- Chang Chen
- grid.41156.370000 0001 2314 964XDepartment of Neurology, Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210008 China ,grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Xiaokuang Ma
- grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Jing Wei
- grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Neha Shakir
- grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Jessica K. Zhang
- grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Le Zhang
- grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Antoine Nehme
- grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Yuehua Cui
- grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Deveroux Ferguson
- grid.134563.60000 0001 2168 186XBasic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004 USA
| | - Feng Bai
- Department of Neurology, Affiliated Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, 210008, China.
| | - Shenfeng Qiu
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA.
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Wu Q, Cortez L, Kamali-Jamil R, Sim V, Wille H, Kar S. Implications of exosomes derived from cholesterol-accumulated astrocytes in Alzheimer's disease pathology. Dis Model Mech 2021; 14:dmm048929. [PMID: 34524402 PMCID: PMC8560497 DOI: 10.1242/dmm.048929] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 09/06/2021] [Indexed: 12/25/2022] Open
Abstract
Amyloid β (Aβ) peptides generated from the amyloid precursor protein (APP) play a critical role in the development of Alzheimer's disease (AD) pathology. Aβ-containing neuronal exosomes, which represent a novel form of intercellular communication, have been shown to influence the function/vulnerability of neurons in AD. Unlike neurons, the significance of exosomes derived from astrocytes remains unclear. In this study, we evaluated the significance of exosomes derived from U18666A-induced cholesterol-accumulated astrocytes in the development of AD pathology. Our results show that cholesterol accumulation decreases exosome secretion, whereas lowering cholesterol increases exosome secretion, from cultured astrocytes. Interestingly, exosomes secreted from U18666A-treated astrocytes contain higher levels of APP, APP-C-terminal fragments, soluble APP, APP secretases and Aβ1-40 than exosomes secreted from control astrocytes. Furthermore, we show that exosomes derived from U18666A-treated astrocytes can lead to neurodegeneration, which is attenuated by decreasing Aβ production or by neutralizing exosomal Aβ peptide with an anti-Aβ antibody. These results, taken together, suggest that exosomes derived from cholesterol-accumulated astrocytes can play an important role in trafficking APP/Aβ peptides and influencing neuronal viability in the affected regions of the AD brain.
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Affiliation(s)
- Qi Wu
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB T6G 2G3, Canada
| | - Leonardo Cortez
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB T6G 2G3, Canada
| | - Razieh Kamali-Jamil
- Department of Biochemistry, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2G3, Canada
| | - Valerie Sim
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB T6G 2G3, Canada
| | - Holger Wille
- Department of Biochemistry, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2G3, Canada
| | - Satyabrata Kar
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB T6G 2G3, Canada
- Department of Biochemistry, Center for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2G3, Canada
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Understanding and Treating Niemann-Pick Type C Disease: Models Matter. Int J Mol Sci 2020; 21:ijms21238979. [PMID: 33256121 PMCID: PMC7730076 DOI: 10.3390/ijms21238979] [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: 10/06/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 02/06/2023] Open
Abstract
Biomedical research aims to understand the molecular mechanisms causing human diseases and to develop curative therapies. So far, these goals have been achieved for a small fraction of diseases, limiting factors being the availability, validity, and use of experimental models. Niemann–Pick type C (NPC) is a prime example for a disease that lacks a curative therapy despite substantial breakthroughs. This rare, fatal, and autosomal-recessive disorder is caused by defects in NPC1 or NPC2. These ubiquitously expressed proteins help cholesterol exit from the endosomal–lysosomal system. The dysfunction of either causes an aberrant accumulation of lipids with patients presenting a large range of disease onset, neurovisceral symptoms, and life span. Here, we note general aspects of experimental models, we describe the line-up used for NPC-related research and therapy development, and we provide an outlook on future topics.
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Wang Y, Wu Q, Anand BG, Karthivashan G, Phukan G, Yang J, Thinakaran G, Westaway D, Kar S. Significance of cytosolic cathepsin D in Alzheimer's disease pathology: Protective cellular effects of PLGA nanoparticles against β-amyloid-toxicity. Neuropathol Appl Neurobiol 2020; 46:686-706. [PMID: 32716575 DOI: 10.1111/nan.12647] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 06/25/2020] [Accepted: 07/12/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND Evidence suggests that amyloid β (Aβ) peptides play an important role in the degeneration of neurons during the development of Alzheimer's disease (AD), the prevalent cause of dementia affecting the elderly. The endosomal-lysosomal system, which acts as a major site for Aβ metabolism, has been shown to exhibit abnormalities in vulnerable neurons of the AD brain, reflected by enhanced levels/expression of lysosomal enzymes including cathepsin D (CatD). At present, the implication of CatD in selective neuronal vulnerability in AD pathology remains unclear. METHODS We evaluated the role of CatD in the degeneration of neurons in Aβ-treated cultures, transgenic AD mouse model (that is 5xFAD) and post mortem AD brain samples. RESULTS Our results showed that Aβ1-42 -induced toxicity in cortical cultured neurons is associated with impaired lysosomal integrity, enhanced levels of carbonylated proteins and tau phosphorylation. The cellular and cytosolic levels/activity of CatD are also elevated in cultured neurons following exposure to Aβ peptide. Additionally, we observed that CatD cellular and subcellular levels/activity are increased in the affected cortex, but not in the unaffected cerebellum, of 5xFAD mice and post mortem AD brains. Interestingly, treatment of cultured neurons with nanoparticles PLGA, which targets lysosomal system, attenuated Aβ toxicity by reducing the levels of carbonylated proteins, tau phosphorylation and the level/distribution/activity of CatD. CONCLUSION Our study reveals that increased cytosolic level/activity of CatD play an important role in determining neuronal vulnerability in AD. Additionally, native PLGA can protect neurons against Aβ toxicity by restoring lysosomal membrane integrity, thus signifying its implication in attenuating AD.
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Affiliation(s)
- Y Wang
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Q Wu
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - B G Anand
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - G Karthivashan
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - G Phukan
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - J Yang
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - G Thinakaran
- Department of Molecular Medicine, and Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, 33613, USA
| | - D Westaway
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - S Kar
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
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Sullivan SE, Liao M, Smith RV, White C, Lagomarsino VN, Xu J, Taga M, Bennett DA, De Jager PL, Young-Pearse TL. Candidate-based screening via gene modulation in human neurons and astrocytes implicates FERMT2 in Aβ and TAU proteostasis. Hum Mol Genet 2020; 28:718-735. [PMID: 30371777 DOI: 10.1093/hmg/ddy376] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/15/2018] [Accepted: 10/16/2018] [Indexed: 11/13/2022] Open
Abstract
Large-scale 'omic' studies investigating the pathophysiological processes that lead to Alzheimer's disease (AD) dementia have identified an increasing number of susceptibility genes, many of which are poorly characterized and have not previously been implicated in AD. Here, we evaluated the utility of human induced pluripotent stem cell-derived neurons and astrocytes as tools to systematically test AD-relevant cellular phenotypes following perturbation of candidate genes identified by genome-wide studies. Lentiviral-mediated delivery of shRNAs was used to modulate expression of 66 genes in astrocytes and 52 genes in induced neurons. Five genes (CNN2, GBA, GSTP1, MINT2 and FERMT2) in neurons and nine genes (CNN2, ITGB1, MINT2, SORL1, VLDLR, NPC1, NPC2, PSAP and SCARB2) in astrocytes significantly altered extracellular amyloid-β (Aβ) levels. Knockdown of AP3M2, CNN2, GSTP1, NPC1, NPC2, PSAP and SORL1 reduced interleukin-6 levels in astrocytes. Only knockdown of FERMT2 led to a reduction in the proportion of TAU that is phosphorylated. Further, CRISPR-Cas9 targeting of FERMT2 in both familial AD (fAD) and fAD-corrected human neurons validated the findings of reduced extracellular Aβ. Interestingly, FERMT2 reduction had no effect on the Aβ42:40 ratio in corrected neurons and a reduction of phospho-tau, but resulted in an elevation in Aβ42:40 ratio and no reduction in phospho-tau in fAD neurons. Taken together, this study has prioritized 15 genes as being involved in contributing to Aβ accumulation, phosphorylation of tau and/or cytokine secretion, and, as illustrated with FERMT2, it sets the stage for further cell-type-specific dissection of the role of these genes in AD.
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Affiliation(s)
- Sarah E Sullivan
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Meichen Liao
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Robert V Smith
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Charles White
- Center for Translational and Computational Neuroimmunology, Department of Neurology, Columbia University Medical Center, New York, NY, USA
| | - Valentina N Lagomarsino
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Jishu Xu
- Cell Circuits Program, Broad Institute, Cambridge, MA, USA
| | - Mariko Taga
- Center for Translational and Computational Neuroimmunology, Department of Neurology, Columbia University Medical Center, New York, NY, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Philip L De Jager
- Cell Circuits Program, Broad Institute, Cambridge, MA, USA.,Center for Translational and Computational Neuroimmunology, Department of Neurology, Columbia University Medical Center, New York, NY, USA
| | - Tracy L Young-Pearse
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
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Ourdev D, Schmaus A, Kar S. Kainate Receptor Activation Enhances Amyloidogenic Processing of APP in Astrocytes. Mol Neurobiol 2018; 56:5095-5110. [PMID: 30484111 DOI: 10.1007/s12035-018-1427-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/13/2018] [Indexed: 12/21/2022]
Abstract
Kainic acid (KA) is an analogue of the excitatory neurotransmitter glutamate that, when injected systemically into adult rats, can trigger seizures and progressive neuronal loss in a manner that mirrors the neuropathology of human mesial temporal lobe epilepsy. However, biomolecular mechanisms responsible for the neuronal loss that occurs as a consequence of this treatment remains elusive. We have recently reported that toxicity induced by KA can partly be mediated by astrocyte-derived amyloid β (Aβ) peptides, which are critical in the development of Alzheimer's disease (AD). Nonetheless, little is known how KA can influence amyloid precursor protein (APP) levels and processing in astrocytes. Thus, in the present study using human U-373 astrocytoma and rat primary astrocytes, we evaluated the role of KA on APP metabolism. Our results revealed that KA treatment increased the levels of APP and its cleaved products (α-/β-CTFs) in cultured U-373 astrocytoma and primary astrocytes, without altering the cell viability. The cellular and secretory levels of Aβ1-40/Aβ1-42 were markedly increased in KA-treated astrocytes. We also demonstrated that the steady-state levels of APP-secretases were not altered but the activity of γ-secretase is enhanced in KA-treated U-373 astrocytoma. Furthermore, using selective receptor antagonists, we showed that the effects of KA is mediated by activation of kainate receptors and not NMDA or AMPA receptors. These results suggest that KA can enhance amyloidogenic processing of APP by activating its own receptor leading to increased production/secretion of Aβ-related peptides from activated astrocytes which may contribute to the pathogenesis of temporal lobe epilepsy.
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Affiliation(s)
- D Ourdev
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada
| | - A Schmaus
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Satyabrata Kar
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada. .,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada. .,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada. .,Department of Medicine, University of Alberta, Edmonton, AB, Canada.
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8
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Lemche E. Early Life Stress and Epigenetics in Late-onset Alzheimer's Dementia: A Systematic Review. Curr Genomics 2018; 19:522-602. [PMID: 30386171 PMCID: PMC6194433 DOI: 10.2174/1389202919666171229145156] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Revised: 07/27/2017] [Accepted: 12/12/2017] [Indexed: 11/22/2022] Open
Abstract
Involvement of life stress in Late-Onset Alzheimer's Disease (LOAD) has been evinced in longitudinal cohort epidemiological studies, and endocrinologic evidence suggests involvements of catecholamine and corticosteroid systems in LOAD. Early Life Stress (ELS) rodent models have successfully demonstrated sequelae of maternal separation resulting in LOAD-analogous pathology, thereby supporting a role of insulin receptor signalling pertaining to GSK-3beta facilitated tau hyper-phosphorylation and amyloidogenic processing. Discussed are relevant ELS studies, and findings from three mitogen-activated protein kinase pathways (JNK/SAPK pathway, ERK pathway, p38/MAPK pathway) relevant for mediating environmental stresses. Further considered were the roles of autophagy impairment, neuroinflammation, and brain insulin resistance. For the meta-analytic evaluation, 224 candidate gene loci were extracted from reviews of animal studies of LOAD pathophysiological mechanisms, of which 60 had no positive results in human LOAD association studies. These loci were combined with 89 gene loci confirmed as LOAD risk genes in previous GWAS and WES. Of the 313 risk gene loci evaluated, there were 35 human reports on epigenomic modifications in terms of methylation or histone acetylation. 64 microRNA gene regulation mechanisms were published for the compiled loci. Genomic association studies support close relations of both noradrenergic and glucocorticoid systems with LOAD. For HPA involvement, a CRHR1 haplotype with MAPT was described, but further association of only HSD11B1 with LOAD found; however, association of FKBP1 and NC3R1 polymorphisms was documented in support of stress influence to LOAD. In the brain insulin system, IGF2R, INSR, INSRR, and plasticity regulator ARC, were associated with LOAD. Pertaining to compromised myelin stability in LOAD, relevant associations were found for BIN1, RELN, SORL1, SORCS1, CNP, MAG, and MOG. Regarding epigenetic modifications, both methylation variability and de-acetylation were reported for LOAD. The majority of up-to-date epigenomic findings include reported modifications in the well-known LOAD core pathology loci MAPT, BACE1, APP (with FOS, EGR1), PSEN1, PSEN2, and highlight a central role of BDNF. Pertaining to ELS, relevant loci are FKBP5, EGR1, GSK3B; critical roles of inflammation are indicated by CRP, TNFA, NFKB1 modifications; for cholesterol biosynthesis, DHCR24; for myelin stability BIN1, SORL1, CNP; pertaining to (epi)genetic mechanisms, hTERT, MBD2, DNMT1, MTHFR2. Findings on gene regulation were accumulated for BACE1, MAPK signalling, TLR4, BDNF, insulin signalling, with most reports for miR-132 and miR-27. Unclear in epigenomic studies remains the role of noradrenergic signalling, previously demonstrated by neuropathological findings of childhood nucleus caeruleus degeneration for LOAD tauopathy.
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Affiliation(s)
- Erwin Lemche
- Section of Cognitive Neuropsychiatry, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
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9
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Kodam A, Ourdev D, Maulik M, Hariharakrishnan J, Banerjee M, Wang Y, Kar S. A role for astrocyte-derived amyloid β peptides in the degeneration of neurons in an animal model of temporal lobe epilepsy. Brain Pathol 2018; 29:28-44. [PMID: 29665128 DOI: 10.1111/bpa.12617] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 04/11/2018] [Indexed: 12/13/2022] Open
Abstract
Kainic acid, an analogue of the excitatory neurotransmitter glutamate, can trigger seizures and neurotoxicity in the hippocampus and other limbic structures in a manner that mirrors the neuropathology of human temporal lobe epilepsy (TLE). However, the underlying mechanisms associated with the neurotoxicity remain unclear. Since amyloid-β (Aβ) peptides, which are critical in the development of Alzheimer's disease, can mediate toxicity by activating glutamatergic NMDA receptors, it is likely that the enhanced glutamatergic transmission that renders hippocampal neurons vulnerable to kainic acid treatment may involve Aβ peptides. Thus, we seek to establish what role Aβ plays in kainic acid-induced toxicity using in vivo and in vitro paradigms. Our results show that systemic injection of kainic acid to adult rats triggers seizures, gliosis and loss of hippocampal neurons, along with increased levels/processing of amyloid precursor protein (APP), resulting in the enhanced production of Aβ-related peptides. The changes in APP levels/processing were evident primarily in activated astrocytes, implying a role for astrocytic Aβ in kainic acid-induced toxicity. Accordingly, we showed that treating rat primary cultured astrocytes with kainic acid can lead to increased Aβ production/secretion without any compromise in cell viability. Additionally, we revealed that kainic acid reduces neuronal viability more in neuronal/astrocyte co-cultures than in pure neuronal culture, and this is attenuated by precluding Aβ production. Collectively, these results indicate that increased production/secretion of Aβ-related peptides from activated astrocytes can contribute to neurotoxicity in kainic acid-treated rats. Since kainic acid administration can lead to neuropathological changes resembling TLE, it is likely that APP/Aβ peptides derived from astrocytes may have a role in TLE pathogenesis.
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Affiliation(s)
- A Kodam
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - D Ourdev
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - M Maulik
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - J Hariharakrishnan
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - M Banerjee
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - Y Wang
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
| | - S Kar
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada, T6G 2M8
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10
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Barbero-Camps E, Roca-Agujetas V, Bartolessis I, de Dios C, Fernández-Checa JC, Marí M, Morales A, Hartmann T, Colell A. Cholesterol impairs autophagy-mediated clearance of amyloid beta while promoting its secretion. Autophagy 2018; 14:1129-1154. [PMID: 29862881 PMCID: PMC6103708 DOI: 10.1080/15548627.2018.1438807] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Macroautophagy/autophagy failure with the accumulation of autophagosomes is an early neuropathological feature of Alzheimer disease (AD) that directly affects amyloid beta (Aβ) metabolism. Although loss of presenilin 1 function has been reported to impair lysosomal function and prevent autophagy flux, the detailed mechanism leading to autophagy dysfunction in AD remains to be elucidated. The resemblance between pathological hallmarks of AD and Niemann-Pick Type C disease, including endosome-lysosome abnormalities and impaired autophagy, suggests cholesterol accumulation as a common link. Using a mouse model of AD (APP-PSEN1-SREBF2 mice), expressing chimeric mouse-human amyloid precursor protein with the familial Alzheimer Swedish mutation (APP695swe) and mutant presenilin 1 (PSEN1-dE9), together with a dominant-positive, truncated and active form of SREBF2/SREBP2 (sterol regulatory element binding factor 2), we demonstrated that high brain cholesterol enhanced autophagosome formation, but disrupted its fusion with endosomal-lysosomal vesicles. The combination of these alterations resulted in impaired degradation of Aβ and endogenous MAPT (microtubule associated protein tau), and stimulated autophagy-dependent Aβ secretion. Exacerbated Aβ-induced oxidative stress in APP-PSEN1-SREBF2 mice, due to cholesterol-mediated depletion of mitochondrial glutathione/mGSH, is critical for autophagy induction. In agreement, in vivo mitochondrial GSH recovery with GSH ethyl ester, inhibited autophagosome synthesis by preventing the oxidative inhibition of ATG4B deconjugation activity exerted by Aβ. Moreover, cholesterol-enrichment within the endosomes-lysosomes modified the levels and membrane distribution of RAB7A and SNAP receptors (SNAREs), which affected its fusogenic ability. Accordingly, in vivo treatment with 2-hydroxypropyl-β-cyclodextrin completely rescued these alterations, making it a potential therapeutic tool for AD.
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Affiliation(s)
- Elisabet Barbero-Camps
- a Department of Cell Death and Proliferation , Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) , Barcelona , Spain
| | - Vicente Roca-Agujetas
- a Department of Cell Death and Proliferation , Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) , Barcelona , Spain
| | - Isabel Bartolessis
- a Department of Cell Death and Proliferation , Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) , Barcelona , Spain
| | - Cristina de Dios
- a Department of Cell Death and Proliferation , Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) , Barcelona , Spain.,c Departament de Biomedicina, Facultat de Medicina , Universitat de Barcelona , Barcelona , Spain
| | - Jose C Fernández-Checa
- a Department of Cell Death and Proliferation , Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) , Barcelona , Spain.,d Liver Unit , Hospital Clinic, CIBEREHD , Barcelona , Spain , Research Center for Alcoholic Liver and Pancreatic Diseases , Keck School of Medicine of the University of Southern California , Los Angeles , CA , USA
| | - Montserrat Marí
- a Department of Cell Death and Proliferation , Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) , Barcelona , Spain
| | - Albert Morales
- a Department of Cell Death and Proliferation , Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) , Barcelona , Spain
| | - Tobias Hartmann
- e Experimental Neurology , Saarland University , Homburg/Saar , Germany
| | - Anna Colell
- a Department of Cell Death and Proliferation , Institut d'Investigacions Biomèdiques de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) , Barcelona , Spain.,b Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) , Spain
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11
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Ovchinnikov DA, Korn O, Virshup I, Wells CA, Wolvetang EJ. The Impact of APP on Alzheimer-like Pathogenesis and Gene Expression in Down Syndrome iPSC-Derived Neurons. Stem Cell Reports 2018; 11:32-42. [PMID: 29861166 PMCID: PMC6066957 DOI: 10.1016/j.stemcr.2018.05.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 05/03/2018] [Accepted: 05/04/2018] [Indexed: 12/17/2022] Open
Abstract
Early-onset Alzheimer disease (AD)-like pathology in Down syndrome is commonly attributed to an increased dosage of the amyloid precursor protein (APP) gene. To test this in an isogenic human model, we deleted the supernumerary copy of the APP gene in trisomic Down syndrome induced pluripotent stem cells or upregulated APP expression in euploid human pluripotent stem cells using CRISPRa. Cortical neuronal differentiation shows that an increased APP gene dosage is responsible for increased β-amyloid production, altered Aβ42/40 ratio, and deposition of the pyroglutamate (E3)-containing amyloid aggregates, but not for several tau-related AD phenotypes or increased apoptosis. Transcriptome comparisons demonstrate that APP has a widespread and temporally modulated impact on neuronal gene expression. Collectively, these data reveal an important role for APP in the amyloidogenic aspects of AD but challenge the idea that increased APP levels are solely responsible for increasing specific phosphorylated forms of tau or enhanced neuronal cell death in Down syndrome-associated AD pathogenesis.
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Affiliation(s)
- Dmitry A Ovchinnikov
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane, QLD 4072, Australia
| | - Othmar Korn
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane, QLD 4072, Australia
| | - Isaac Virshup
- Centre for Stem Cell Systems, MDHS, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Christine A Wells
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane, QLD 4072, Australia; Centre for Stem Cell Systems, MDHS, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Ernst J Wolvetang
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane, QLD 4072, Australia.
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12
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Endosomal-Lysosomal Cholesterol Sequestration by U18666A Differentially Regulates Amyloid Precursor Protein (APP) Metabolism in Normal and APP-Overexpressing Cells. Mol Cell Biol 2018. [PMID: 29530923 DOI: 10.1128/mcb.00529-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Amyloid β (Aβ) peptide, derived from amyloid precursor protein (APP), plays a critical role in the development of Alzheimer's disease. Current evidence indicates that altered levels or subcellular distribution of cholesterol can regulate Aβ production and clearance, but it remains unclear how cholesterol sequestration within the endosomal-lysosomal (EL) system can influence APP metabolism. Thus, we evaluated the effects of U18666A, which triggers cholesterol redistribution within the EL system, on mouse N2a cells expressing different levels of APP in the presence or absence of extracellular cholesterol and lipids provided by fetal bovine serum (FBS). Our results reveal that U18666A and FBS differentially increase the levels of APP and its cleaved products, the α-, β-, and η-C-terminal fragments, in N2a cells expressing normal levels of mouse APP (N2awt), higher levels of human wild-type APP (APPwt), or "Swedish" mutant APP (APPsw). The cellular levels of Aβ1-40/Aβ1-42 were markedly increased in U18666A-treated APPwt and APPsw cells. Our studies further demonstrate that APP and its cleaved products are partly accumulated in the lysosomes, possibly due to decreased clearance. Finally, we show that autophagy inhibition plays a role in mediating U18666A effects. Collectively, these results suggest that altered levels and distribution of cholesterol and lipids can differentially regulate APP metabolism depending on the nature of APP expression.
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13
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Miranda AM, Lasiecka ZM, Xu Y, Neufeld J, Shahriar S, Simoes S, Chan RB, Oliveira TG, Small SA, Di Paolo G. Neuronal lysosomal dysfunction releases exosomes harboring APP C-terminal fragments and unique lipid signatures. Nat Commun 2018; 9:291. [PMID: 29348617 PMCID: PMC5773483 DOI: 10.1038/s41467-017-02533-w] [Citation(s) in RCA: 149] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 12/06/2017] [Indexed: 12/11/2022] Open
Abstract
Defects in endolysosomal and autophagic functions are increasingly viewed as key pathological features of neurodegenerative disorders. A master regulator of these functions is phosphatidylinositol-3-phosphate (PI3P), a phospholipid synthesized primarily by class III PI 3-kinase Vps34. Here we report that disruption of neuronal Vps34 function in vitro and in vivo impairs autophagy, lysosomal degradation as well as lipid metabolism, causing endolysosomal membrane damage. PI3P deficiency also promotes secretion of unique exosomes enriched for undigested lysosomal substrates, including amyloid precursor protein C-terminal fragments (APP-CTFs), specific sphingolipids, and the phospholipid bis(monoacylglycero)phosphate (BMP), which normally resides in the internal vesicles of endolysosomes. Secretion of these exosomes requires neutral sphingomyelinase 2 and sphingolipid synthesis. Our results reveal a homeostatic response counteracting lysosomal dysfunction via secretion of atypical exosomes eliminating lysosomal waste and define exosomal APP-CTFs and BMP as candidate biomarkers for endolysosomal dysfunction associated with neurodegenerative disorders.
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Affiliation(s)
- André M Miranda
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, 10032, USA
- Taub Institute for Research on Alzheimer's disease and the Aging Brain, Columbia University Medical Center, New York, NY, 10032, USA
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, 4710-057, Portugal
- ICVS/3B's, PT Government Associate Laboratory, Braga/Guimarães, 4710-057, Portugal
| | - Zofia M Lasiecka
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Yimeng Xu
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Jessi Neufeld
- Taub Institute for Research on Alzheimer's disease and the Aging Brain, Columbia University Medical Center, New York, NY, 10032, USA
- Departments of Neurology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Sanjid Shahriar
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Sabrina Simoes
- Taub Institute for Research on Alzheimer's disease and the Aging Brain, Columbia University Medical Center, New York, NY, 10032, USA
- Departments of Neurology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Robin B Chan
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, 10032, USA
- Taub Institute for Research on Alzheimer's disease and the Aging Brain, Columbia University Medical Center, New York, NY, 10032, USA
| | - Tiago Gil Oliveira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, 4710-057, Portugal
- ICVS/3B's, PT Government Associate Laboratory, Braga/Guimarães, 4710-057, Portugal
| | - Scott A Small
- Taub Institute for Research on Alzheimer's disease and the Aging Brain, Columbia University Medical Center, New York, NY, 10032, USA
- Departments of Neurology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Gilbert Di Paolo
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, 10032, USA.
- Taub Institute for Research on Alzheimer's disease and the Aging Brain, Columbia University Medical Center, New York, NY, 10032, USA.
- Denali Therapeutics, South San Francisco, CA, 94080, USA.
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14
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Joshi AU, Saw NL, Shamloo M, Mochly-Rosen D. Drp1/Fis1 interaction mediates mitochondrial dysfunction, bioenergetic failure and cognitive decline in Alzheimer's disease. Oncotarget 2017; 9:6128-6143. [PMID: 29464060 PMCID: PMC5814200 DOI: 10.18632/oncotarget.23640] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 11/26/2017] [Indexed: 11/25/2022] Open
Abstract
Mitochondrial dynamics, involving a balance between fusion and fission, regulates mitochondrial quality and number. Increasing evidence suggests that dysfunctional mitochondria play a role in Alzheimer's disease (AD). We observed that Drp1 interaction with one of the adaptors, Fis1, is significantly increased in Aβ-treated neurons and AD patient-derived fibroblasts. P110, a seven-amino acid peptide, which specifically inhibits Drp1/Fis1 interaction without affecting the interaction of Drp1 with its other adaptors, attenuated Aβ42-induced mitochondrial recruitment of Drp1 and prevented mitochondrial structural and functional dysfunction in cultured neurons, in cells expressing mutant amyloid precursor protein (KM670/671NL), and in five different AD patient-derived fibroblasts. Importantly, sustained P110 treatment significantly improved behavioral deficits, and reduced Aβ accumulation, energetic failure and oxidative stress in the brain of the AD mouse model, 5XFAD. This suggests that Drp1/Fis1 interaction and excessive mitochondrial fission greatly contribute to Aβ-mediated and AD-related neuropathology and cognitive decline. Therefore, inhibiting excessive Drp1/Fis1-mediated mitochondrial fission may benefit AD patients.
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Affiliation(s)
- Amit U Joshi
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nay L Saw
- Behavioral and Functional Neuroscience Laboratory, Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Mehrdad Shamloo
- Behavioral and Functional Neuroscience Laboratory, Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Daria Mochly-Rosen
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
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15
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Arenas F, Garcia-Ruiz C, Fernandez-Checa JC. Intracellular Cholesterol Trafficking and Impact in Neurodegeneration. Front Mol Neurosci 2017; 10:382. [PMID: 29204109 PMCID: PMC5698305 DOI: 10.3389/fnmol.2017.00382] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 11/02/2017] [Indexed: 12/13/2022] Open
Abstract
Cholesterol is a critical component of membrane bilayers where it plays key structural and functional roles by regulating the activity of diverse signaling platforms and pathways. Particularly enriched in brain, cholesterol homeostasis in this organ is singular with respect to other tissues and exhibits a heterogeneous regulation in distinct brain cell populations. Due to the key role of cholesterol in brain physiology and function, alterations in cholesterol homeostasis and levels have been linked to brain diseases and neurodegeneration. In the case of Alzheimer disease (AD), however, this association remains unclear with evidence indicating that either increased or decreased total brain cholesterol levels contribute to this major neurodegenerative disease. Here, rather than analyzing the role of total cholesterol levels in neurodegeneration, we focus on the contribution of intracellular cholesterol pools, particularly in endolysosomes and mitochondria through its trafficking via specialized membrane domains delineated by the contacts between endoplasmic reticulum and mitochondria, in the onset of prevalent neurodegenerative diseases such as AD, Parkinson disease, and Huntington disease as well as in lysosomal disorders like Niemann-Pick type C disease. We dissect molecular events associated with intracellular cholesterol accumulation, especially in mitochondria, an event that results in impaired mitochondrial antioxidant defense and function. A better understanding of the mechanisms involved in the distribution of cholesterol in intracellular compartments may shed light on the role of cholesterol homeostasis disruption in neurodegeneration and may pave the way for specific intervention opportunities.
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Affiliation(s)
- Fabian Arenas
- Department of Cell Death and Proliferation, Instituto de Investigaciones Biomédicas de Barcelona, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
- Liver Unit and Hospital Clinic I Provincial, IDIBAPS, Barcelona, Spain
- Centro de Investigación Biomédica en Red, CIBEREHD, Barcelona, Spain
| | - Carmen Garcia-Ruiz
- Department of Cell Death and Proliferation, Instituto de Investigaciones Biomédicas de Barcelona, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
- Liver Unit and Hospital Clinic I Provincial, IDIBAPS, Barcelona, Spain
- Centro de Investigación Biomédica en Red, CIBEREHD, Barcelona, Spain
- Southern California Research Center for ALDP and Cirrhosis, Los Angeles, CA, United States
| | - Jose C. Fernandez-Checa
- Department of Cell Death and Proliferation, Instituto de Investigaciones Biomédicas de Barcelona, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
- Liver Unit and Hospital Clinic I Provincial, IDIBAPS, Barcelona, Spain
- Centro de Investigación Biomédica en Red, CIBEREHD, Barcelona, Spain
- Southern California Research Center for ALDP and Cirrhosis, Los Angeles, CA, United States
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16
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Maulik M, Vergote D, Phukan G, Chung J, Thinakaran G, Kar S. The Effects of Extracellular Serum Concentration on APP Processing in Npc1-Deficient APP-Overexpressing N2a Cells. Mol Neurobiol 2017; 55:5757-5766. [DOI: 10.1007/s12035-017-0799-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 10/11/2017] [Indexed: 11/29/2022]
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