scholarly journals Astrocyte- and neuron-derived extracellular vesicles from Alzheimer’s disease patients effect complement-mediated neurotoxicity

2020 ◽  
Author(s):  
Carlos J Nogueras-Ortiz ◽  
Vasiliki Mahairaki ◽  
Francheska Delgado-Peraza ◽  
Debamitra Das ◽  
Konstantinos Avgerinos ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Extracellular Vesicles ◽  
Cortical Neurons ◽  
Membrane Attack Complex ◽  
Neurite Density ◽  
Complement Inhibitors ◽  
Rat Cortical Neurons ◽  
And Control ◽  
Human Ipsc

AbstractWe have previously shown that blood astrocytic-origin extracellular vesicles (AEVs) from Alzheimer’s disease (AD) patients contain high complement levels. To test the hypothesis that circulating EVs from AD patients can induce complement-mediated neurodegeneration, we assessed the neurotoxicity of immunocaptured AEVs (with anti-GLAST antibody), neuronal-origin NEVs (with anti-L1CAM antibody), and multicellular-origin (with anti-CD81 antibody) EVs from the plasma of AD, frontotemporal lobar degeneration (FTLD) and control participants. AEVs (and, less effectively, NEVs) of AD participants induced Membrane Attack Complex (MAC) expression on recipient neurons, membrane disruption, reduced neurite density, and decreased cell viability in rat cortical neurons and human IPSC-derived neurons. Neurodegenerative effects were not produced by multicellular-origin EVs from AD participants or AEVs/NEVs from FTLD or control participants, and were suppressed by the MAC inhibitor CD59 and other complement inhibitors. Our results support the stated hypothesis and suggest that neuronal MAC deposition is necessary for AEV/NEV-mediated neurodegeneration in AD.

scholarly journals Astrocyte- and Neuron-Derived Extracellular Vesicles from Alzheimer’s Disease Patients Effect Complement-Mediated Neurotoxicity

Cells ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1618 ◽  
Author(s):  
Carlos J. Nogueras-Ortiz ◽  
Vasiliki Mahairaki ◽  
Francheska Delgado-Peraza ◽  
Debamitra Das ◽  
Konstantinos Avgerinos ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cell Viability ◽  
Extracellular Vesicles ◽  
Cortical Neurons ◽  
Membrane Attack Complex ◽  
Neurite Density ◽  
Complement Inhibitors ◽  
Rat Cortical Neurons ◽  
And Control

We have previously shown that blood astrocytic-origin extracellular vesicles (AEVs) from Alzheimer’s disease (AD) patients contain high complement levels. To test the hypothesis that circulating EVs from AD patients can induce complement-mediated neurotoxicity involving Membrane Attack Complex (MAC) formation, we assessed the effects of immunocaptured AEVs (using anti-GLAST antibody), in comparison with neuronal-origin (N)EVs (using anti-L1CAM antibody), and nonspecific CD81+ EVs (using anti-CD81 antibody), from the plasma of AD, frontotemporal lobar degeneration (FTLD), and control participants. AEVs (and, less effectively, NEVs) of AD participants induced Membrane Attack Complex (MAC) expression on recipient neurons (by immunohistochemistry), membrane disruption (by EthD-1 assay), reduced neurite density (by Tuj-1 immunohistochemistry), and decreased cell viability (by MTT assay) in rat cortical neurons and human iPSC-derived neurons. Demonstration of decreased cell viability was replicated in a separate cohort of autopsy-confirmed AD patients. These effects were not produced by CD81+ EVs from AD participants or AEVs/NEVs from FTLD or control participants, and were suppressed by the MAC inhibitor CD59 and other complement inhibitors. Our results support the stated hypothesis and should motivate future studies on the roles of neuronal MAC deposition and AEV/NEV uptake, as effectors of neurodegeneration in AD.

scholarly journals Alzheimer’s disease brain-derived tau-containing extracellular vesicles: Pathobiology and GABAergic neuronal transmission

2020 ◽  
Author(s):  
Zhi Ruan ◽  
Dhruba Pathak ◽  
Srinidhi Venkatesan Kalavai ◽  
Asuka Yoshii-Kitahara ◽  
Satoshi Muraoka ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Extracellular Vesicles ◽  
Cortical Neurons ◽  
Pyramidal Neurons ◽  
Molecular Layer ◽  
Pyramidal Cells ◽  
Gabaergic Neurons ◽  
Dot Blot ◽  
Patch Clamp Recording

AbstractExtracellular vesicles (EVs) propagate tau pathology for Alzheimer’s disease (AD). How EV transmission influences AD are, nonetheless, poorly understood. To these ends, the physicochemical and molecular structure-function relationships of human brain-derived EVs, from AD and prodromal AD (pAD), were compared to non-demented controls (CTRL). AD EVs were shown to be significantly enriched in epitope-specific tau oligomers versus pAD or CTRL EVs assayed by dot-blot and atomic force microscopy tests. AD EVs were efficiently internalized by murine cortical neurons and transferred tau with higher aggregation potency than pAD and CTRL EVs. Strikingly, inoculation of tau-containing AD EVs into the outer molecular layer of the dentate gyrus induced tau propagation throughout the hippocampus. This was seen in 22 months-old C57BL/6 mice at 4.5 months post-injection by semiquantitative brain-wide immunohistochemistry tests with multiple anti-phospho-tau (p-tau) antibodies. Inoculation of the equal amount of tau from CTRL EVs or as oligomer or fibril-enriched fraction from the same AD donor showed little propagation. AD EVs induced tau accumulation in the hippocampus as oligomers or sarkosyl-insoluble proteins. Unexpectedly, p-tau cells were mostly GAD67+ GABAergic neurons and to a lesser extent, GluR2/3+ excitatory mossy cells, showing preferential EV-mediated GABAergic neuronal tau propagation. Whole-cell patch clamp recording of Cornu Ammonis (CA1) pyramidal cells showed significant reduction in the amplitude of spontaneous inhibitory post-synaptic currents. This was accompanied by reductions in c-fos+ GAD67+GABAergic neurons and GAD67+ GABAergic neuronal puncta surrounding pyramidal neurons in the CA1 region confirming reduced interneuronal projections. Our study posits a novel tau-associated pathological mechanism for brain-derived EVs.

scholarly journals Neuron-Derived Extracellular Vesicles Modulate Microglia Activation and Function

Biology ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 948
Author(s):  
Hui Peng ◽  
Brock T. Harvey ◽  
Christopher I. Richards ◽  
Kimberly Nixon
Keyword(s):  
Extracellular Vesicles ◽  
Cortical Neurons ◽  
Molecular Mechanisms ◽  
Proinflammatory Response ◽  
Tnf Α ◽  
Rat Cortical Neurons ◽  
The Central Nervous System ◽  
And Function ◽  
And Control ◽  
Brain Homeostasis

Microglia act as the immune cells of the central nervous system (CNS). They play an important role in maintaining brain homeostasis but also in mediating neuroimmune responses to insult. The interactions between neurons and microglia represent a key process for neuroimmune regulation and subsequent effects on CNS integrity. However, the molecular mechanisms of neuron-glia communication in regulating microglia function are not fully understood. One recently described means of this intercellular communication is via nano-sized extracellular vesicles (EVs) that transfer a large diversity of molecules between neurons and microglia, such as proteins, lipids, and nucleic acids. To determine the effects of neuron-derived EVs (NDEVs) on microglia, NDEVs were isolated from the culture supernatant of rat cortical neurons. When NDEVs were added to primary cultured rat microglia, we found significantly improved microglia viability via inhibition of apoptosis. Additionally, application of NDEVs to cultured microglia also inhibited the expression of activation surface markers on microglia. Furthermore, NDEVs reduced the LPS-induced proinflammatory response in microglia according to reduced gene expression of proinflammatory cytokines (TNF-α, IL-6, MCP-1) and iNOS, but increased expression of the anti-inflammatory cytokine, IL-10. These findings support that neurons critically regulate microglia activity and control inflammation via EV-mediated neuron–glia communication. (Supported by R21AA025563 and R01AA025591).

scholarly journals Drug repurposing for Alzheimer’s disease based on transcriptional profiling of human iPSC-derived cortical neurons

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Gareth Williams ◽  
Ariana Gatt ◽  
Earl Clarke ◽  
Jonathan Corcoran ◽  
Patrick Doherty ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cortical Neurons ◽  
Transcriptional Profiling ◽  
Drug Repurposing ◽  
Human Ipsc

scholarly journals Alix and Syntenin-1 direct amyloid precursor protein trafficking into extracellular vesicles

2020 ◽  
Author(s):  
Allaura S. Cone ◽  
Stephanie N. Hurwitz ◽  
Glorida S. Lee ◽  
Xuegang Yuan ◽  
Yi Zhou ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Subcellular Localization ◽  
Amyloid Precursor Protein ◽  
Extracellular Vesicles ◽  
Protein Trafficking ◽  
Cortical Neurons ◽  
Molecular Mechanisms ◽  
Precursor Protein ◽  
Amyloid Precursor Protein Trafficking

Abstract Background: Endosomal trafficking and amyloidogenic cleavage of amyloid precursor protein (APP) is believed to play a role in the neurodegeneration observed in Alzheimer’s disease (AD). Recent evidence has suggested that packaging and secretion of APP and its amyloidogenic cleaved product (βAPP) into small extracellular vesicles (EVs) may facilitate uptake of these neurotoxic factors during disease progression. However, the molecular mechanisms underlying trafficking of APP into EVs are poorly understood. Results: In this study, the mechanism and impact of amyloid precursor protein trafficking into extracellular vesicles (EVs) were assessed by a series of inducible gene knockdowns. We demonstrate that vesicle-associated proteins Alix and Syntenin-1 are essential for proper subcellular localization and efficient EV secretion of APP via an endosomal sorting complexes required for transport (ESCRT)-independent pathway. The neurotoxic C-terminal fragment (CTF) of APP is similarly secreted in association with small vesicles. These mechanisms are conserved in terminally differentiated neuron-like cells. Furthermore, knockdown of Alix and Syntenin-1 alters the subcellular localization of APP, sequestering the precursor protein to endoplasmic reticulum and endolysosomal compartments, respectively. Finally, transfer of small EVs containing APP confers an increase in reactive oxygen species production and neurotoxicity to human induced pluripotent stem cell-derived cortical neurons and naïve primary neurons, an effect that is ameliorated by Alix and Syntenin-1 depletion. Conclusions: Altogether these findings elucidate a novel mechanism for understanding the intracellular trafficking of APP and βAPP into secreted extracellular vesicles, and the resultant potential impact on neurotoxicity in the context of Alzheimer’s disease amyloidopathy.

scholarly journals Proteomic Profiling of Extracellular Vesicles Derived from Cerebrospinal Fluid of Alzheimer’s Disease Patients: A Pilot Study

Cells ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1959 ◽  
Author(s):  
Satoshi Muraoka ◽  
Mark P. Jedrychowski ◽  
Kiran Yanamandra ◽  
Seiko Ikezu ◽  
Steven P. Gygi ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cerebrospinal Fluid ◽  
Extracellular Vesicles ◽  
Protein Composition ◽  
Amyloid Plaque ◽  
Label Free ◽  
Proteomic Profiling ◽  
Proteomics Analysis ◽  
And Control

Pathological hallmarks of Alzheimer’s disease (AD) are deposits of amyloid beta (Aβ) and hyper-phosphorylated tau aggregates in brain plaques. Recent studies have highlighted the importance of Aβ and tau-containing extracellular vesicles (EVs) in AD. We therefore examined EVs separated from cerebrospinal fluid (CSF) of AD, mild cognitive impairment (MCI), and control (CTRL) patient samples to profile the protein composition of CSF EV. EV fractions were separated from AD (n = 13), MCI (n = 10), and CTRL (n = 10) CSF samples using MagCapture Exosome Isolation kit. The CSF-derived EV proteins were identified and quantified by label-free and tandem mass tag (TMT)-labeled mass spectrometry. Label-free proteomics analysis identified 2546 proteins that were significantly enriched for extracellular exosome ontology by Gene Ontology analysis. Canonical Pathway Analysis revealed glia-related signaling. Quantitative proteomics analysis, moreover, showed that EVs expressed 1284 unique proteins in AD, MCI and CTRL groups. Statistical analysis identified three proteins—HSPA1A, NPEPPS, and PTGFRN—involved in AD progression. In addition, the PTGFRN showed a moderate correlation with amyloid plaque (rho = 0.404, p = 0.027) and tangle scores (rho = 0.500, p = 0.005) in AD, MCI and CTRL. Based on the CSF EV proteomics, these data indicate that three proteins, HSPA1A, NPEPPS and PTGFRN, may be used to monitor the progression of MCI to AD.

scholarly journals Alix and Syntenin-1 direct amyloid precursor protein and amyloid beta trafficking into extracellular vesicles

2020 ◽  
Author(s):  
Allaura S. Cone ◽  
Stephanie N. Hurwitz ◽  
Glorida S. Lee ◽  
Xuegang Yuan ◽  
Yi Zhou ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Subcellular Localization ◽  
Amyloid Precursor Protein ◽  
Extracellular Vesicles ◽  
Amyloid Beta ◽  
Cortical Neurons ◽  
Molecular Mechanisms ◽  
Precursor Protein ◽  
Endosomal Trafficking

Abstract Background: Endosomal trafficking and amyloidogenic cleavage of amyloid precursor protein (APP) is believed to play a role in the neurodegeneration observed in Alzheimer’s disease (AD). Recent evidence has suggested that packaging and secretion of APP and amyloid beta into small extracellular vesicles (EVs) may facilitate uptake of these neurotoxic factors during disease progression. However, the molecular mechanisms underlying trafficking of APP into EVs are poorly understood. Results: In this study, the mechanism and impact of amyloid precursor protein (APP) trafficking into extracellular vesicles (EVs) were assessed by a series of inducible gene knockdowns. We demonstrate that vesicle-associated proteins Alix and Syntenin-1 are essential for proper subcellular localization and efficient EV secretion of APP via an endosomal sorting complexes required for transport (ESCRT)-independent pathway. The neurotoxic metabolite amyloid beta (Aβ) is similarly secreted in association with small vesicles. These mechanisms are conserved in terminally differentiated neuron-like cells. Furthermore, knockdown of Alix and Syntenin-1 alters the subcellular localization of APP, sequestering the precursor protein to endoplasmic reticulum and endolysosomal compartments, respectively. Finally, transfer of small EVs containing APP confers an increase in reactive oxygen species production and neurotoxicity to human induced pluripotent stem cell-derived cortical neurons and naïve primary neurons, an effect that is ameliorated by Alix and Syntenin-1 depletion. Conclusions: Altogether these findings elucidate a novel mechanism for understanding the intracellular trafficking of APP and Aβ into secreted extracellular vesicles, and the resultant potential impact on neurotoxicity in the context of Alzheimer’s disease amyloidopathy.

scholarly journals Alzheimer’s disease brain-derived extracellular vesicles spread tau pathology in interneurons

Brain ◽  
2020 ◽  
Author(s):  
Zhi Ruan ◽  
Dhruba Pathak ◽  
Srinidhi Venkatesan Kalavai ◽  
Asuka Yoshii-Kitahara ◽  
Satoshi Muraoka ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Extracellular Vesicles ◽  
Cortical Neurons ◽  
Acid Decarboxylase ◽  
Gabaergic Interneurons ◽  
Phosphorylated Tau ◽  
Tau Pathology ◽  
Tau Oligomers ◽  
Prodromal Alzheimer’S Disease

Abstract Extracellular vesicles are highly transmissible and play critical roles in the propagation of tau pathology, although the underlying mechanism remains elusive. Here, for the first time, we comprehensively characterized the physicochemical structure and pathogenic function of human brain-derived extracellular vesicles isolated from Alzheimer’s disease, prodromal Alzheimer’s disease, and non-demented control cases. Alzheimer’s disease extracellular vesicles were significantly enriched in epitope-specific tau oligomers in comparison to prodromal Alzheimer’s disease or control extracellular vesicles as determined by dot blot and atomic force microscopy. Alzheimer’s disease extracellular vesicles were more efficiently internalized by murine cortical neurons, as well more efficient in transferring and misfolding tau, than prodromal Alzheimer’s disease and control extracellular vesicles in vitro. Strikingly, the inoculation of Alzheimer’s disease or prodromal Alzheimer’s disease extracellular vesicles containing only 300 pg of tau into the outer molecular layer of the dentate gyrus of 18-month-old C57BL/6 mice resulted in the accumulation of abnormally phosphorylated tau throughout the hippocampus by 4.5 months, whereas inoculation of an equal amount of tau from control extracellular vesicles, isolated tau oligomers, or fibrils from the same Alzheimer’s disease donor showed little tau pathology. Furthermore, Alzheimer’s disease extracellular vesicles induced misfolding of endogenous tau in both oligomeric and sarkosyl-insoluble forms in the hippocampal region. Unexpectedly, phosphorylated tau was primarily accumulated in glutamic acid decarboxylase 67 (GAD67) GABAergic interneurons and, to a lesser extent, glutamate receptor 2/3-positive excitatory mossy cells, showing preferential extracellular vesicle-mediated GABAergic interneuronal tau propagation. Whole-cell patch clamp recordings of CA1 pyramidal cells showed significant reduction in the amplitude of spontaneous inhibitory post-synaptic currents. This was accompanied by reductions in c-fos+ GAD67+ neurons and GAD67+ neuronal puncta surrounding pyramidal neurons in the CA1 region, confirming reduced GABAergic transmission in this region. Our study posits a novel mechanism for the spread of tau in hippocampal GABAergic interneurons via brain-derived extracellular vesicles and their subsequent neuronal dysfunction.

Sign in / Sign up

Export Citation Format

Share Document