1
|
Ye J, Wan H, Chen S, Liu GP. Targeting tau in Alzheimer's disease: from mechanisms to clinical therapy. Neural Regen Res 2024; 19:1489-1498. [PMID: 38051891 PMCID: PMC10883484 DOI: 10.4103/1673-5374.385847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 08/16/2023] [Indexed: 12/07/2023] Open
Abstract
ABSTRACT Alzheimer's disease is the most prevalent neurodegenerative disease affecting older adults. Primary features of Alzheimer's disease include extracellular aggregation of amyloid-β plaques and the accumulation of neurofibrillary tangles, formed by tau protein, in the cells. While there are amyloid-β-targeting therapies for the treatment of Alzheimer's disease, these therapies are costly and exhibit potential negative side effects. Mounting evidence suggests significant involvement of tau protein in Alzheimer's disease-related neurodegeneration. As an important microtubule-associated protein, tau plays an important role in maintaining the stability of neuronal microtubules and promoting axonal growth. In fact, clinical studies have shown that abnormal phosphorylation of tau protein occurs before accumulation of amyloid-β in the brain. Various therapeutic strategies targeting tau protein have begun to emerge, and are considered possible methods to prevent and treat Alzheimer's disease. Specifically, abnormalities in post-translational modifications of the tau protein, including aberrant phosphorylation, ubiquitination, small ubiquitin-like modifier (SUMO)ylation, acetylation, and truncation, contribute to its microtubule dissociation, misfolding, and subcellular missorting. This causes mitochondrial damage, synaptic impairments, gliosis, and neuroinflammation, eventually leading to neurodegeneration and cognitive deficits. This review summarizes the recent findings on the underlying mechanisms of tau protein in the onset and progression of Alzheimer's disease and discusses tau-targeted treatment of Alzheimer's disease.
Collapse
Affiliation(s)
- Jinwang Ye
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, Guangdong Province, China
| | - Huali Wan
- Department of Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province, China
| | - Sihua Chen
- Shenzhen Key Laboratory of Marine Biotechnology and Ecology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, Guangdong Province, China
| | - Gong-Ping Liu
- Co-innovation Center of Neurodegeneration, Nantong University, Nantong, Jiangsu Province, China
- Department of Pathophysiology, School of Basic Medicine and the Collaborative Innovation Center for Brain Science, Key Laboratory of Ministry of Education of China and Hubei Province for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| |
Collapse
|
2
|
Chu D, Yang X, Wang J, Zhou Y, Gu JH, Miao J, Wu F, Liu F. Tau truncation in the pathogenesis of Alzheimer's disease: a narrative review. Neural Regen Res 2024; 19:1221-1232. [PMID: 37905868 DOI: 10.4103/1673-5374.385853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 07/25/2023] [Indexed: 11/02/2023] Open
Abstract
ABSTRACT Alzheimer's disease is characterized by two major neuropathological hallmarks-the extracellular β-amyloid plaques and intracellular neurofibrillary tangles consisting of aggregated and hyperphosphorylated Tau protein. Recent studies suggest that dysregulation of the microtubule-associated protein Tau, especially specific proteolysis, could be a driving force for Alzheimer's disease neurodegeneration. Tau physiologically promotes the assembly and stabilization of microtubules, whereas specific truncated fragments are sufficient to induce abnormal hyperphosphorylation and aggregate into toxic oligomers, resulting in them gaining prion-like characteristics. In addition, Tau truncations cause extensive impairments to neural and glial cell functions and animal cognition and behavior in a fragment-dependent manner. This review summarizes over 60 proteolytic cleavage sites and their corresponding truncated fragments, investigates the role of specific truncations in physiological and pathological states of Alzheimer's disease, and summarizes the latest applications of strategies targeting Tau fragments in the diagnosis and treatment of Alzheimer's disease.
Collapse
Affiliation(s)
- Dandan Chu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Xingyue Yang
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, Jiangsu Province, China
| | - Jing Wang
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, Jiangsu Province, China
| | - Yan Zhou
- Department of Biochemistry and Molecular Biology, School of Medicine, Nantong University, Nantong, Jiangsu Province, China
| | - Jin-Hua Gu
- Department of Clinical Pharmacy, Affiliated Maternity and Child Health Care Hospital of Nantong University, Nantong University, Nantong, Jiangsu Province, China
| | - Jin Miao
- Laboratory of Animal Center, Nantong University, Nantong, Jiangsu Province, China
| | - Feng Wu
- Department of Pharmacology, School of Pharmacy, Nantong University, Nantong, Jiangsu Province, China
| | - Fei Liu
- Department of Neurochemistry, Inge Grundke-Iqbal Research Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| |
Collapse
|
3
|
Song Z, Wang KW, Hagar HTC, Chen HR, Kuan CY, Zhang K, Kuo MH. Hyperphosphorylated Tau Inflicts Intracellular Stress Responses that Are Mitigated by Apomorphine. Mol Neurobiol 2024; 61:2653-2671. [PMID: 37919601 PMCID: PMC11043184 DOI: 10.1007/s12035-023-03689-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 09/30/2023] [Indexed: 11/04/2023]
Abstract
Abnormal phosphorylation of the microtubule-binding protein tau in the brain is a key pathological marker for Alzheimer's disease and additional neurodegenerative tauopathies. However, how hyperphosphorylated tau causes cellular dysfunction or death that underlies neurodegeneration remains an unsolved question critical for the understanding of disease mechanism and the design of efficacious drugs. Using a recombinant hyperphosphorylated tau protein (p-tau) synthesized by the PIMAX approach, we examined how cells responded to the cytotoxic tau and explored means to enhance cellular resistance to tau attack. Upon p-tau uptake, the intracellular calcium levels rose promptly. Gene expression analyses revealed that p-tau potently triggered endoplasmic reticulum (ER) stress, unfolded protein response (UPR), ER stress-associated apoptosis, and pro-inflammation in cells. Proteomics studies showed that p-tau diminished heme oxygenase-1 (HO-1), an ER stress-associated anti-inflammation and anti-oxidative stress regulator, while stimulated the accumulation of MIOS and other proteins. p-Tau-induced ER stress-associated apoptosis and pro-inflammation are ameliorated by apomorphine, a brain-permeable prescription drug widely used to treat Parkinson's disease symptoms, and by overexpression of HO-1. Our results reveal probable cellular functions targeted by hyperphosphorylated tau. Some of these dysfunctions and stress responses have been linked to neurodegeneration in Alzheimer's disease. The observations that the ill effects of p-tau can be mitigated by a small compound and by overexpressing HO-1 that is otherwise diminished in the treated cells inform new directions of Alzheimer's disease drug discovery.
Collapse
Affiliation(s)
- Zhenfeng Song
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Kuang-Wei Wang
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Hsiao-Tien Chien Hagar
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Hong-Ru Chen
- Department of Neuroscience, School of Medicine, University of Virginia, Charlottesville, VA, 22903, USA
- Present address: Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan, 112304
| | - Chia-Yi Kuan
- Department of Neuroscience, School of Medicine, University of Virginia, Charlottesville, VA, 22903, USA
| | - Kezhong Zhang
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
| | - Min-Hao Kuo
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA.
| |
Collapse
|
4
|
Tam S, Wear D, Morrone CD, Yu WH. The complexity of extracellular vesicles: Bridging the gap between cellular communication and neuropathology. J Neurochem 2024. [PMID: 38650384 DOI: 10.1111/jnc.16108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 03/12/2024] [Accepted: 03/31/2024] [Indexed: 04/25/2024]
Abstract
Brain-derived extracellular vesicles (EVs) serve a prominent role in maintaining homeostasis and contributing to pathology in health and disease. This review establishes a crucial link between physiological processes leading to EV biogenesis and their impacts on disease. EVs are involved in the clearance and transport of proteins and nucleic acids, responding to changes in cellular processes associated with neurodegeneration, including autophagic disruption, organellar dysfunction, aging, and other cell stresses. In neurodegenerative disorders (e.g., Alzheimer's disease, Parkinson's disease, etc.), EVs contribute to the spread of pathological proteins like amyloid β, tau, ɑ-synuclein, prions, and TDP-43, exacerbating neurodegeneration and accelerating disease progression. Despite evidence for both neuropathological and neuroprotective effects of EVs, the mechanistic switch between their physiological and pathological functions remains elusive, warranting further research into their involvement in neurodegenerative disease. Moreover, owing to their innate ability to traverse the blood-brain barrier and their ubiquitous nature, EVs emerge as promising candidates for novel diagnostic and therapeutic strategies. The review uniquely positions itself at the intersection of EV cell biology, neurophysiology, and neuropathology, offering insights into the diverse biological roles of EVs in health and disease.
Collapse
Affiliation(s)
- Stephanie Tam
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Darcy Wear
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Christopher D Morrone
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Wai Haung Yu
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
5
|
Terron HM, Parikh SJ, Abdul-Hay SO, Sahara T, Kang D, Dickson DW, Saftig P, LaFerla FM, Lane S, Leissring MA. Prominent tauopathy and intracellular β-amyloid accumulation triggered by genetic deletion of cathepsin D: implications for Alzheimer disease pathogenesis. Alzheimers Res Ther 2024; 16:70. [PMID: 38575959 PMCID: PMC10996108 DOI: 10.1186/s13195-024-01443-6] [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: 10/19/2023] [Accepted: 03/31/2024] [Indexed: 04/06/2024]
Abstract
BACKGROUND Cathepsin D (CatD) is a lysosomal protease that degrades both the amyloid-β protein (Aβ) and the microtubule-associated protein, tau, which accumulate pathognomonically in Alzheimer disease (AD), but few studies have examined the role of CatD in the development of Aβ pathology and tauopathy in vivo. METHODS CatD knockout (KO) mice were crossed to human amyloid precursor protein (hAPP) transgenic mice, and amyloid burden was quantified by ELISA and immunohistochemistry (IHC). Tauopathy in CatD-KO mice, as initially suggested by Gallyas silver staining, was further characterized by extensive IHC and biochemical analyses. Controls included human tau transgenic mice (JNPL3) and another mouse model of a disease (Krabbe A) characterized by pronounced lysosomal dysfunction. Additional experiments examined the effects of CatD inhibition on tau catabolism in vitro and in cultured neuroblastoma cells with inducible expression of human tau. RESULTS Deletion of CatD in hAPP transgenic mice triggers large increases in cerebral Aβ, manifesting as intense, exclusively intracellular aggregates; extracellular Aβ deposition, by contrast, is neither triggered by CatD deletion, nor affected in older, haploinsufficient mice. Unexpectedly, CatD-KO mice were found to develop prominent tauopathy by just ∼ 3 weeks of age, accumulating sarkosyl-insoluble, hyperphosphorylated tau exceeding the pathology present in aged JNPL3 mice. CatD-KO mice exhibit pronounced perinuclear Gallyas silver staining reminiscent of mature neurofibrillary tangles in human AD, together with widespread phospho-tau immunoreactivity. Striking increases in sarkosyl-insoluble phospho-tau (∼ 1250%) are present in CatD-KO mice but notably absent from Krabbe A mice collected at an identical antemortem interval. In vitro and in cultured cells, we show that tau catabolism is slowed by blockade of CatD proteolytic activity, including via competitive inhibition by Aβ42. CONCLUSIONS Our findings support a major role for CatD in the proteostasis of both Aβ and tau in vivo. To our knowledge, the CatD-KO mouse line is the only model to develop detectable Aβ accumulation and profound tauopathy in the absence of overexpression of hAPP or human tau with disease-associated mutations. Given that tauopathy emerges from disruption of CatD, which can itself be potently inhibited by Aβ42, our findings suggest that impaired CatD activity may represent a key mechanism linking amyloid accumulation and tauopathy in AD.
Collapse
Affiliation(s)
- Heather M Terron
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine (UCI MIND), Irvine, CA, 92697, USA
| | - Sagar J Parikh
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine (UCI MIND), Irvine, CA, 92697, USA
| | - Samer O Abdul-Hay
- Department of Neuroscience, Mayo Clinic Florida, Jacksonville, FL, 32224, USA
| | - Tomoko Sahara
- Department of Neuroscience, Mayo Clinic Florida, Jacksonville, FL, 32224, USA
| | - Dongcheul Kang
- Department of Neuroscience, Mayo Clinic Florida, Jacksonville, FL, 32224, USA
| | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic Florida, Jacksonville, FL, 32224, USA
| | - Paul Saftig
- Institut für Biochemie, Christian-Albrechts-Universität zu Kiel, D-24098, Kiel, Germany
| | - Frank M LaFerla
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine (UCI MIND), Irvine, CA, 92697, USA
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, 92697, USA
| | - Shelley Lane
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine (UCI MIND), Irvine, CA, 92697, USA
| | - Malcolm A Leissring
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine (UCI MIND), Irvine, CA, 92697, USA.
- Department of Neuroscience, Mayo Clinic Florida, Jacksonville, FL, 32224, USA.
| |
Collapse
|
6
|
Balczon R, Lin MT, Voth S, Nelson AR, Schupp JC, Wagener BM, Pittet JF, Stevens T. Lung endothelium, tau, and amyloids in health and disease. Physiol Rev 2024; 104:533-587. [PMID: 37561137 DOI: 10.1152/physrev.00006.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 06/26/2023] [Accepted: 08/04/2023] [Indexed: 08/11/2023] Open
Abstract
Lung endothelia in the arteries, capillaries, and veins are heterogeneous in structure and function. Lung capillaries in particular represent a unique vascular niche, with a thin yet highly restrictive alveolar-capillary barrier that optimizes gas exchange. Capillary endothelium surveys the blood while simultaneously interpreting cues initiated within the alveolus and communicated via immediately adjacent type I and type II epithelial cells, fibroblasts, and pericytes. This cell-cell communication is necessary to coordinate the immune response to lower respiratory tract infection. Recent discoveries identify an important role for the microtubule-associated protein tau that is expressed in lung capillary endothelia in the host-pathogen interaction. This endothelial tau stabilizes microtubules necessary for barrier integrity, yet infection drives production of cytotoxic tau variants that are released into the airways and circulation, where they contribute to end-organ dysfunction. Similarly, beta-amyloid is produced during infection. Beta-amyloid has antimicrobial activity, but during infection it can acquire cytotoxic activity that is deleterious to the host. The production and function of these cytotoxic tau and amyloid variants are the subject of this review. Lung-derived cytotoxic tau and amyloid variants are a recently discovered mechanism of end-organ dysfunction, including neurocognitive dysfunction, during and in the aftermath of infection.
Collapse
Affiliation(s)
- Ron Balczon
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Mike T Lin
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Sarah Voth
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine, Monroe, Louisiana, United States
| | - Amy R Nelson
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Jonas C Schupp
- Pulmonary and Critical Care Medicine, Department of Internal Medicine, Yale University, New Haven, Connecticut, United States
- Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany
- German Center for Lung Research (DZL), Hannover, Germany
| | - Brant M Wagener
- Department of Anesthesiology and Perioperative Medicine, University of Alabama-Birmingham, Birmingham, Alabama, United States
| | - Jean-Francois Pittet
- Department of Anesthesiology and Perioperative Medicine, University of Alabama-Birmingham, Birmingham, Alabama, United States
| | - Troy Stevens
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Department of Internal Medicine, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| |
Collapse
|
7
|
Padmanabhan P, Kneynsberg A, Cruz E, Briner A, Götz J. Single-molecule imaging of Tau reveals how phosphorylation affects its movement and confinement in living cells. Mol Brain 2024; 17:7. [PMID: 38347594 PMCID: PMC10863257 DOI: 10.1186/s13041-024-01078-6] [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: 05/21/2023] [Accepted: 01/22/2024] [Indexed: 02/15/2024] Open
Abstract
Tau is a microtubule-associated protein that is regulated by post-translational modifications. The most studied of these modifications is phosphorylation, which affects Tau's aggregation and loss- and gain-of-functions, including the interaction with microtubules, in Alzheimer's disease and primary tauopathies. However, little is known about how Tau's phosphorylation state affects its dynamics and organisation at the single-molecule level. Here, using quantitative single-molecule localisation microscopy, we examined how mimicking or abrogating phosphorylation at 14 disease-associated serine and threonine residues through mutagenesis influences the behaviour of Tau in live Neuro-2a cells. We observed that both pseudohyperphosphorylated Tau (TauE14) and phosphorylation-deficient Tau (TauA14) exhibit a heterogeneous mobility pattern near the plasma membrane. Notably, we found that the mobility of TauE14 molecules was higher than wild-type Tau molecules, while TauA14 molecules displayed lower mobility. Moreover, TauA14 was organised in a filament-like structure resembling cytoskeletal filaments, within which TauA14 exhibited spatial and kinetic heterogeneity. Our study provides a direct visualisation of how the phosphorylation state of Tau affects its spatial and temporal organisation, presumably reflecting the phosphorylation-dependent changes in the interactions between Tau and its partners. We suggest that alterations in Tau dynamics resulting from aberrant changes in phosphorylation could be a critical step in its pathological dysregulation.
Collapse
Affiliation(s)
- Pranesh Padmanabhan
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, 4072, Brisbane, Australia.
| | - Andrew Kneynsberg
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, 4072, Brisbane, Australia
| | - Esteban Cruz
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, 4072, Brisbane, Australia
| | - Adam Briner
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, 4072, Brisbane, Australia
| | - Jürgen Götz
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, 4072, Brisbane, Australia.
| |
Collapse
|
8
|
Schultheis N, Connell A, Kapral A, Becker RJ, Mueller R, Shah S, O'Donnell M, Roseman M, Wang W, Yin F, Weiss R, Selleck SB. Heparan sulfate modified proteins affect cellular processes central to neurodegeneration and modulate presenilin function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.23.576895. [PMID: 38328107 PMCID: PMC10849577 DOI: 10.1101/2024.01.23.576895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Mutations in presenilin-1 (PSEN1) are the most common cause of familial, early-onset Alzheimer's disease (AD), typically producing cognitive deficits in the fourth decade. A variant of APOE, APOE3 Christchurch (APOE3ch) , was found associated with protection from both cognitive decline and Tau accumulation in a 70-year-old bearing the disease-causing PSEN1-E280A mutation. The amino acid change in ApoE3ch is within the heparan sulfate (HS) binding domain of APOE, and purified APOEch showed dramatically reduced affinity for heparin, a highly sulfated form of HS. The physiological significance of ApoE3ch is supported by studies of a mouse bearing a knock-in of this human variant and its effects on microglia reactivity and Aβ-induced Tau deposition. The studies reported here examine the function of heparan sulfate-modified proteoglycans (HSPGs) in cellular and molecular pathways affecting AD-related cell pathology in human cell lines and mouse astrocytes. The mechanisms of HSPG influences on presenilin- dependent cell loss and pathology were evaluated in Drosophila using knockdown of the presenilin homolog, Psn , together with partial loss of function of sulfateless (sfl) , a homolog of NDST1 , a gene specifically affecting HS sulfation. HSPG modulation of autophagy, mitochondrial function, and lipid metabolism were shown to be conserved in cultured human cell lines, Drosophila , and mouse astrocytes. RNAi of Ndst1 reduced intracellular lipid levels in wild-type mouse astrocytes or those expressing humanized variants of APOE, APOE3 , and APOE4 . RNA-sequence analysis of human cells deficient in HS synthesis demonstrated effects on the transcriptome governing lipid metabolism, autophagy, and mitochondrial biogenesis and showed significant enrichment in AD susceptibility genes identified by GWAS. Neuron-directed knockdown of Psn in Drosophila produced cell loss in the brain and behavioral phenotypes, both suppressed by simultaneous reductions in sfl mRNA levels. Abnormalities in mitochondria, liposome morphology, and autophagosome-derived structures in animals with Psn knockdown were also rescued by simultaneous reduction of sfl. sfl knockdown reversed Psn- dependent transcript changes in genes affecting lipid transport, metabolism, and monocarboxylate carriers. These findings support the direct involvement of HSPGs in AD pathogenesis.
Collapse
|
9
|
Lolicato F, Steringer JP, Saleppico R, Beyer D, Fernandez-Sobaberas J, Unger S, Klein S, Riegerová P, Wegehingel S, Müller HM, Schmitt XJ, Kaptan S, Freund C, Hof M, Šachl R, Chlanda P, Vattulainen I, Nickel W. Disulfide bridge-dependent dimerization triggers FGF2 membrane translocation into the extracellular space. eLife 2024; 12:RP88579. [PMID: 38252473 PMCID: PMC10945597 DOI: 10.7554/elife.88579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2024] Open
Abstract
Fibroblast growth factor 2 (FGF2) exits cells by direct translocation across the plasma membrane, a type I pathway of unconventional protein secretion. This process is initiated by phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2)-dependent formation of highly dynamic FGF2 oligomers at the inner plasma membrane leaflet, inducing the formation of lipidic membrane pores. Cell surface heparan sulfate chains linked to glypican-1 (GPC1) capture FGF2 at the outer plasma membrane leaflet, completing FGF2 membrane translocation into the extracellular space. While the basic steps of this pathway are well understood, the molecular mechanism by which FGF2 oligomerizes on membrane surfaces remains unclear. In the current study, we demonstrate the initial step of this process to depend on C95-C95 disulfide-bridge-mediated FGF2 dimerization on membrane surfaces, producing the building blocks for higher FGF2 oligomers that drive the formation of membrane pores. We find FGF2 with a C95A substitution to be defective in oligomerization, pore formation, and membrane translocation. Consistently, we demonstrate a C95A variant of FGF2 to be characterized by a severe secretion phenotype. By contrast, while also important for efficient FGF2 secretion from cells, a second cysteine residue on the molecular surface of FGF2 (C77) is not involved in FGF2 oligomerization. Rather, we find C77 to be part of the interaction interface through which FGF2 binds to the α1 subunit of the Na,K-ATPase, the landing platform for FGF2 at the inner plasma membrane leaflet. Using cross-linking mass spectrometry, atomistic molecular dynamics simulations combined with a machine learning analysis and cryo-electron tomography, we propose a mechanism by which disulfide-bridged FGF2 dimers bind with high avidity to PI(4,5)P2 on membrane surfaces. We further propose a tight coupling between FGF2 secretion and the formation of ternary signaling complexes on cell surfaces, hypothesizing that C95-C95-bridged FGF2 dimers are functioning as the molecular units triggering autocrine and paracrine FGF2 signaling.
Collapse
Affiliation(s)
- Fabio Lolicato
- Heidelberg University Biochemistry CenterHeidelbergGermany
- Department of Physics, University of HelsinkiHelsinkiFinland
| | | | | | - Daniel Beyer
- Heidelberg University Biochemistry CenterHeidelbergGermany
| | | | | | - Steffen Klein
- Schaller Research Group, Department of Infectious Diseases-Virology, Heidelberg University HospitalHeidelbergGermany
| | - Petra Riegerová
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of SciencesPragueCzech Republic
| | | | | | - Xiao J Schmitt
- Institute for Chemistry and Biochemistry, Freie Universität BerlinBerlinGermany
| | - Shreyas Kaptan
- Department of Physics, University of HelsinkiHelsinkiFinland
| | - Christian Freund
- Institute for Chemistry and Biochemistry, Freie Universität BerlinBerlinGermany
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Radek Šachl
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of SciencesPragueCzech Republic
| | - Petr Chlanda
- Schaller Research Group, Department of Infectious Diseases-Virology, Heidelberg University HospitalHeidelbergGermany
| | | | - Walter Nickel
- Heidelberg University Biochemistry CenterHeidelbergGermany
| |
Collapse
|
10
|
Yu Q, Du F, Belli I, Gomes PA, Sotiropoulos I, Waites CL. Glucocorticoid stress hormones stimulate vesicle-free Tau secretion and spreading in the brain. Cell Death Dis 2024; 15:73. [PMID: 38238309 PMCID: PMC10796385 DOI: 10.1038/s41419-024-06458-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 01/07/2024] [Accepted: 01/08/2024] [Indexed: 01/22/2024]
Abstract
Chronic stress and elevated levels of glucocorticoids (GCs), the main stress hormones, accelerate Alzheimer's disease (AD) onset and progression. A major driver of AD progression is the spreading of pathogenic Tau protein between brain regions, precipitated by neuronal Tau secretion. While stress and high GC levels are known to induce intraneuronal Tau pathology (i.e. hyperphosphorylation, oligomerization) in animal models, their role in trans-neuronal Tau spreading is unexplored. Here, we find that GCs promote secretion of full-length, primarily vesicle-free, phosphorylated Tau from murine hippocampal neurons and ex vivo brain slices. This process requires neuronal activity and the kinase GSK3β. GCs also dramatically enhance trans-neuronal Tau spreading in vivo, and this effect is blocked by an inhibitor of Tau oligomerization and type 1 unconventional protein secretion. These findings uncover a potential mechanism by which stress/GCs stimulate Tau propagation in AD.
Collapse
Affiliation(s)
- Qing Yu
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and Aging Brain, Columbia University Irving Medical Center, New York, NY, USA
| | - Fang Du
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and Aging Brain, Columbia University Irving Medical Center, New York, NY, USA
| | - Irla Belli
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and Aging Brain, Columbia University Irving Medical Center, New York, NY, USA
| | - Patricia A Gomes
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Ioannis Sotiropoulos
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
- Institute of Biosciences and Applications, National Centre for Scientific Research (NCSR) Demokritos, Agia Paraskevi, Greece
| | - Clarissa L Waites
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and Aging Brain, Columbia University Irving Medical Center, New York, NY, USA.
- Department of Neuroscience, Columbia University, New York, NY, USA.
| |
Collapse
|
11
|
Schneeweis A, Pak DTS. Wherefore Art Tau? Functional importance of site-specific tau phosphorylation in diverse subcellular domains. Int J Biochem Cell Biol 2023; 164:106475. [PMID: 37778693 DOI: 10.1016/j.biocel.2023.106475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 09/26/2023] [Accepted: 09/26/2023] [Indexed: 10/03/2023]
Abstract
Tau has canonically been considered as an axonal protein, but studies have observed tau localization in other subcellular domains of neurons. This relocated tau has been identified in both physiological and pathological conditions, and it is often labeled mislocalized. Furthermore, these forms of tau are referred to as "hyperphosphorylated" without specifying the phosphosites involved. On the contrary, we speculate that tau may have multiple physiological functions in various locations regulated via specific phosphorylation sites, although this picture is obscured by a lack of comprehensive phosphosite analysis. Here, we examine findings in the literature on the subcellular location of tau and potential roles tau has in those regions. We intentionally focus on the site-specific phosphorylated patterns involved in governing these properties, which are not well elucidated. To facilitate understanding of these events, we have begun establishing a comprehensive map of tau phosphorylation signatures. Such efforts may clarify tau's diverse physiological functions beyond the axon as well as promote development of novel therapeutic strategies directed against distinct tau subpopulations.
Collapse
Affiliation(s)
- Amanda Schneeweis
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Daniel T S Pak
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC 20057, USA.
| |
Collapse
|
12
|
Terron HM, Parikh SJ, Abdul-Hay SO, Sahara T, Kang D, Dickson DW, Saftig P, LaFerla FM, Lane S, Leissring MA. Prominent tauopathy and intracellular β-amyloid accumulation triggered by genetic deletion of cathepsin D: Implications for Alzheimer disease pathogenesis. RESEARCH SQUARE 2023:rs.3.rs-3464352. [PMID: 37961253 PMCID: PMC10635349 DOI: 10.21203/rs.3.rs-3464352/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Background Cathepsin D (CatD) is a lysosomal protease that degrades both the amyloid-β protein (Aβ) and the microtubule-associated protein, tau, which accumulate pathognomonically in Alzheimer disease (AD), but few studies have examined the role of CatD in the development of Aβ pathology and tauopathy in vivo. Methods CatD knockout (KO) mice were crossed to human amyloid precursor protein (hAPP) transgenic mice, and amyloid burden was quantified by ELISA and immunohistochemistry (IHC). Tauopathy in CatD-KO mice, as initially suggested by Gallyas silver staining, was further characterized by extensive IHC and biochemical analyses. Controls included human tau transgenic mice (JNPL3) and another mouse model characterized by pronounced lysosomal dysfunction (Krabbe A). Additional experiments examined the effects of CatD inhibition on tau catabolism in vitro and in cultured neuroblastoma cells with inducible expression of human tau. Results Deletion of CatD in hAPP transgenic mice triggers large increases in cerebral Aβ, manifesting as intense, exclusively intracellular aggregates; extracellular Aβ deposition, by contrast, is neither triggered by CatD deletion, nor affected in older, haploinsufficient mice. Unexpectedly, CatDKO mice were found to develop prominent tauopathy by just ~ 3 weeks of age, accumulating sarkosyl-insoluble, hyperphosphorylated tau exceeding the pathology in aged JNPL3 mice. CatDKO mice exhibit pronounced perinuclear Gallyas silver staining reminiscent of mature neurofibrillary tangles in human AD, together with widespread phospho-tau immunoreactivity. Striking increases in sarkosyl-insoluble phospho-tau (~ 1250%) are present in CatD-KO mice, but notably absent from Krabbe A mice collected at an identical antemortem interval. In vitro and in cultured cells, we show that tau catabolism is slowed by blockade of CatD proteolytic activity, including via competitive inhibition by Aβ42. Conclusions Our findings support a major role for CatD in the proteostasis of both Aβ and tau in vivo. To our knowledge, CatD-KO mice are the only model to develop detectable Aβ acumulation and profound tauopathy in the absence of overexpression of hAPP or human tau with disease-associated mutations. Given that tauopathy emerges from disruption of CatD, which can itself be potently inhibited by Aβ42, our findings suggest that impaired CatD activity may represent a key mechanism linking amyloid accumulation and tauopathy in AD.
Collapse
|
13
|
Dimou E, Katsinelos T, Meisl G, Tuck BJ, Keeling S, Smith AE, Hidari E, Lam JYL, Burke M, Lövestam S, Ranasinghe RT, McEwan WA, Klenerman D. Super-resolution imaging unveils the self-replication of tau aggregates upon seeding. Cell Rep 2023; 42:112725. [PMID: 37393617 PMCID: PMC7614924 DOI: 10.1016/j.celrep.2023.112725] [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: 10/31/2022] [Revised: 04/03/2023] [Accepted: 06/14/2023] [Indexed: 07/04/2023] Open
Abstract
Tau is a soluble protein interacting with tubulin to stabilize microtubules. However, under pathological conditions, it becomes hyperphosphorylated and aggregates, a process that can be induced by treating cells with exogenously added tau fibrils. Here, we employ single-molecule localization microscopy to resolve the aggregate species formed in early stages of seeded tau aggregation. We report that entry of sufficient tau assemblies into the cytosol induces the self-replication of small tau aggregates, with a doubling time of 5 h inside HEK cells and 1 day in murine primary neurons, which then grow into fibrils. Seeding occurs in the vicinity of the microtubule cytoskeleton, is accelerated by the proteasome, and results in release of small assemblies into the media. In the absence of seeding, cells still spontaneously form small aggregates at lower levels. Overall, our work provides a quantitative picture of the early stages of templated seeded tau aggregation in cells.
Collapse
Affiliation(s)
- Eleni Dimou
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK; UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK.
| | - Taxiarchis Katsinelos
- UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK; MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Georg Meisl
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Benjamin J Tuck
- UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK
| | - Sophie Keeling
- UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK
| | - Annabel E Smith
- UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK
| | - Eric Hidari
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK; UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK
| | - Jeff Y L Lam
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK; UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK
| | - Melanie Burke
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK; UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK
| | - Sofia Lövestam
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Rohan T Ranasinghe
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK; UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK
| | - William A McEwan
- UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK
| | - David Klenerman
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK; UK Dementia Research Institute at University of Cambridge, Department of Clinical Neurosciences, Hills Road, Cambridge CB2 0AH, UK.
| |
Collapse
|
14
|
Waites C, Yu Q, Du F, Belli I, Gomes P, Sotiropoulos I. Glucocorticoid stress hormones stimulate vesicle-free Tau secretion and spreading in the brain. RESEARCH SQUARE 2023:rs.3.rs-3097174. [PMID: 37503224 PMCID: PMC10371092 DOI: 10.21203/rs.3.rs-3097174/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Chronic stress and elevated levels of glucocorticoids (GCs), the main stress hormones, accelerate Alzheimer's disease (AD) onset and progression. A major driver of AD progression is the spreading of pathogenic Tau protein between brain regions, precipitated by neuronal Tau secretion. While stress and high GC levels are known to induce intraneuronal Tau pathology (i.e. hyperphosphorylation, oligomerization) in animal models, their role in trans-neuronal Tau spreading is unexplored. Here, we find that GCs promote secretion of full-length, vesicle-free, phosphorylated Tau from murine hippocampal neurons and ex vivo brain slices. This process occurs via type 1 unconventional protein secretion (UPS) and requires neuronal activity and the kinase GSK3b. GCs also dramatically enhance trans-neuronal Tau spreading in vivo, and this effect is blocked by an inhibitor of Tau oligomerization and type 1 UPS. These findings uncover a potential mechanism by which stress/GCs stimulate Tau propagation in AD.
Collapse
Affiliation(s)
| | - Qing Yu
- Columbia University Irving Medical Center
| | - Fang Du
- Columbia University Irving Medical Center
| | - Irla Belli
- Columbia University Irving Medical Center
| | - Patrícia Gomes
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal
| | | |
Collapse
|
15
|
Yu Q, Du F, Belli I, Gomes PA, Sotiropoulos I, Waites CL. Glucocorticoid stress hormones stimulate vesicle-free Tau secretion and spreading in the brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.07.544054. [PMID: 37333306 PMCID: PMC10274779 DOI: 10.1101/2023.06.07.544054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Chronic stress and elevated levels of glucocorticoids (GCs), the main stress hormones, accelerate Alzheimer's disease (AD) onset and progression. A major driver of AD progression is the spreading of pathogenic Tau protein between brain regions, precipitated by neuronal Tau secretion. While stress and high GC levels are known to induce intraneuronal Tau pathology ( i.e. hyperphosphorylation, oligomerization) in animal models, their role in trans-neuronal Tau spreading is unexplored. Here, we find that GCs promote secretion of full-length, vesicle-free, phosphorylated Tau from murine hippocampal neurons and ex vivo brain slices. This process occurs via type 1 unconventional protein secretion (UPS) and requires neuronal activity and the kinase GSK3β. GCs also dramatically enhance trans-neuronal Tau spreading in vivo , and this effect is blocked by an inhibitor of Tau oligomerization and type 1 UPS. These findings uncover a potential mechanism by which stress/GCs stimulate Tau propagation in AD.
Collapse
|
16
|
Lopez DM, Maltby CJ, Warming H, Divecha N, Vargas-Caballero M, Coldwell MJ, Deinhardt K. A luminescence-based reporter to study tau secretion reveals overlapping mechanisms for the release of healthy and pathological tau. Front Neurosci 2023; 17:1196007. [PMID: 37342467 PMCID: PMC10277490 DOI: 10.3389/fnins.2023.1196007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/17/2023] [Indexed: 06/23/2023] Open
Abstract
In Alzheimer's disease, tau pathology is thought to spread via a prion-like manner along connected neuronal networks. For this to occur, the usually cytosolic tau protein must be secreted via an unconventional mechanism prior to uptake into the connected neuron. While secretion of healthy and pathological tau has been documented, it remains under-investigated whether this occurs via overlapping or distinct processes. Here, we established a sensitive bioluminescence-based assay to assess mechanisms underlying the secretion of pseudohyperphosphorylated and wild-type tau in cultured murine hippocampal neurons. We found that under basal conditions, both wild-type and mutant tau are secreted, with mutant tau being more robustly secreted. Pharmacological stimulation of neuronal activity led to a modest increase of wild-type and mutant tau secretion, whereas inhibition of activity had no effect. Interestingly, inhibition of heparin sulfate proteoglycan (HSPG) biosynthesis drastically decreased secretion of both wild-type and mutant tau without affecting cell viability. This shows that native and pathological tau share release mechanisms; both activity-dependent and non-activity-dependent secretion of tau is facilitated by HSPGs.
Collapse
|
17
|
Song Z, Wang KW, Hagar HTC, Chen HR, Kuan CY, Zhang K, Kuo MH. Hyperphosphorylated tau Inflicts Intracellular Stress Responses That Are Mitigated by Apomorphine. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.13.540661. [PMID: 37292976 PMCID: PMC10245566 DOI: 10.1101/2023.05.13.540661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Background Abnormal phosphorylation of the microtubule-binding protein tau in the brain is a key pathological marker for Alzheimer's disease and additional neurodegenerative tauopathies. However, how hyperphosphorylated tau causes cellular dysfunction or death that underlie neurodegeneration remains an unsolved question critical for the understanding of disease mechanism and the design of efficacious drugs. Methods Using a recombinant hyperphosphorylated tau protein (p-tau) synthesized by the PIMAX approach, we examined how cells responded to the cytotoxic tau and explored means to enhance cellular resistance to tau attack. Results Upon p-tau uptake, the intracellular calcium levels rose promptly. Gene expression analyses revealed that p-tau potently triggered endoplasmic reticulum (ER) stress, Unfolded Protein Response (UPR), ER stress-associated apoptosis, and pro-inflammation in cells. Proteomics studies showed that p-tau diminished heme oxygenase-1 (HO-1), an ER stress associated anti-inflammation and anti-oxidative stress regulator, while stimulated the accumulation of MIOS and other proteins. P-tau-induced ER stress-associated apoptosis and pro-inflammation are ameliorated by apomorphine, a brain-permeable prescription drug widely used to treat Parkinson's disease symptoms, and by overexpression of HO-1. Conclusion Our results reveal probable cellular functions targeted by hyperphosphorylated tau. Some of these dysfunctions and stress responses have been linked to neurodegeneration in Alzheimer's disease. The observations that the ill effects of p-tau can be mitigated by a small compound and by overexpressing HO-1 that is otherwise diminished in the treated cells inform new directions of Alzheimer's disease drug discovery.
Collapse
|
18
|
Abbate C. The Adult Neurogenesis Theory of Alzheimer's Disease. J Alzheimers Dis 2023:JAD221279. [PMID: 37182879 DOI: 10.3233/jad-221279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Alzheimer's disease starts in neural stem cells (NSCs) in the niches of adult neurogenesis. All primary factors responsible for pathological tau hyperphosphorylation are inherent to adult neurogenesis and migration. However, when amyloid pathology is present, it strongly amplifies tau pathogenesis. Indeed, the progressive accumulation of extracellular amyloid-β deposits in the brain triggers a state of chronic inflammation by microglia. Microglial activation has a significant pro-neurogenic effect that fosters the process of adult neurogenesis and supports neuronal migration. Unfortunately, this "reactive" pro-neurogenic activity ultimately perturbs homeostatic equilibrium in the niches of adult neurogenesis by amplifying tau pathogenesis in AD. This scenario involves NSCs in the subgranular zone of the hippocampal dentate gyrus in late-onset AD (LOAD) and NSCs in the ventricular-subventricular zone along the lateral ventricles in early-onset AD (EOAD), including familial AD (FAD). Neuroblasts carrying the initial seed of tau pathology travel throughout the brain via neuronal migration driven by complex signals and convey the disease from the niches of adult neurogenesis to near (LOAD) or distant (EOAD) brain regions. In these locations, or in close proximity, a focus of degeneration begins to develop. Then, tau pathology spreads from the initial foci to large neuronal networks along neural connections through neuron-to-neuron transmission.
Collapse
Affiliation(s)
- Carlo Abbate
- IRCCS Fondazione Don Carlo Gnocchi ONLUS, Milan, Italy
| |
Collapse
|
19
|
El Mammeri N, Gampp O, Duan P, Hong M. Membrane-induced tau amyloid fibrils. Commun Biol 2023; 6:467. [PMID: 37117483 PMCID: PMC10147698 DOI: 10.1038/s42003-023-04847-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 04/17/2023] [Indexed: 04/30/2023] Open
Abstract
The intrinsically disordered protein tau aggregates into β-sheet amyloid fibrils that spread in human brains afflicted with Alzheimer's disease and other neurodegenerative diseases. Tau interaction with lipid membranes might play a role in the formation and spreading of these pathological aggregates. Here we investigate the conformation and assembly of membrane-induced tau aggregates using solid-state NMR and transmission electron microscopy. A tau construct that encompasses the microtubule-binding repeats and a proline-rich domain is reconstituted into cholesterol-containing phospholipid membranes. 2D 13C-13C correlation spectra indicate that tau converted from a random coil to a β-sheet conformation over weeks. Small unilamellar vesicles (SUVs) cause different equilibrium conformations from large unilamellar vesicles (LUVs) and multilamellar vesicles (MLVs). Importantly, SUV-bound tau developed long fibrils that exhibit the characteristic β-sheet chemical shifts of Tyr310 in heparin-fibrillized tau. In comparison, LUVs and MLVs do not induce fibrils but cause different β-sheet aggregates. Lipid-protein correlation spectra indicate that these tau aggregates reside at the membrane-water interface, without inserting into the middle of the lipid bilayer. Removal of cholesterol from the SUVs abolished the fibrils, indicating that both membrane curvature and cholesterol are required for tau fibril formation. These results have implications for how lipid membranes might nucleate tau aggregates.
Collapse
Affiliation(s)
- Nadia El Mammeri
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Olivia Gampp
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Pu Duan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
20
|
Chen J, Fan A, Li S, Xiao Y, Fu Y, Chen JS, Zi D, Zeng LH, Tan J. APP mediates tau uptake and its overexpression leads to the exacerbated tau pathology. Cell Mol Life Sci 2023; 80:123. [PMID: 37071198 PMCID: PMC11071805 DOI: 10.1007/s00018-023-04774-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 03/11/2023] [Accepted: 03/16/2023] [Indexed: 04/19/2023]
Abstract
Alzheimer's disease (AD), as the most common type of dementia, has two pathological hallmarks, extracellular senile plaques composed of β-amyloid peptides and intracellular neurofibrillary tangles containing phosphorylated-tau protein. Amyloid precursor protein (APP) and tau each play central roles in AD, although how APP and tau interact and synergize in the disease process is largely unknown. Here, we showed that soluble tau interacts with the N-terminal of APP in vitro in cell-free and cell culture systems, which can be further confirmed in vivo in the brain of 3XTg-AD mouse. In addition, APP is involved in the cellular uptake of tau through endocytosis. APP knockdown or N-terminal APP-specific antagonist 6KApoEp can prevent tau uptake in vitro, resulting in an extracellular tau accumulation in cultured neuronal cells. Interestingly, in APP/PS1 transgenic mouse brain, the overexpression of APP exacerbated tau propagation. Moreover, in the human tau transgenic mouse brain, overexpression of APP promotes tau phosphorylation, which is significantly remediated by 6KapoEp. All these results demonstrate the important role of APP in the tauopathy of AD. Targeting the pathological interaction of N-terminal APP with tau may provide an important therapeutic strategy for AD.
Collapse
Affiliation(s)
- Jiang Chen
- Key Laboratory of Endemic and Ethnic Diseases, Laboratory of Molecular Biology, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Anran Fan
- Guizhou Provincial Key Laboratory for Regenerative Medicine, Stem Cell and Tissue Engineering Research Center, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Song Li
- First Affiliated Hospital of Dalian Medical University, Dalian, 116021, Liaoning, China
| | - Yan Xiao
- Key Laboratory of Endemic and Ethnic Diseases, Laboratory of Molecular Biology, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Yanlin Fu
- Key Laboratory of Endemic and Ethnic Diseases, Laboratory of Molecular Biology, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Jun-Sheng Chen
- Key Laboratory of Endemic and Ethnic Diseases, Laboratory of Molecular Biology, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China
| | - Dan Zi
- Department of Gynecology, Guizhou Provincial People's Hospital, Guiyang, 550025, Guizhou, China
| | - Ling-Hui Zeng
- Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, Zhejiang, China
| | - Jun Tan
- Key Laboratory of Endemic and Ethnic Diseases, Laboratory of Molecular Biology, Ministry of Education, Guizhou Medical University, Guiyang, 550025, Guizhou, China.
- Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, School of Medicine, Hangzhou City University, Hangzhou, 310015, Zhejiang, China.
| |
Collapse
|
21
|
Beltran-Lobo P, Reid MJ, Jimenez-Sanchez M, Verkhratsky A, Perez-Nievas BG, Noble W. Astrocyte adaptation in Alzheimer's disease: a focus on astrocytic P2X7R. Essays Biochem 2023; 67:119-130. [PMID: 36449279 PMCID: PMC10011405 DOI: 10.1042/ebc20220079] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 11/09/2022] [Accepted: 11/11/2022] [Indexed: 12/02/2022]
Abstract
Astrocytes are key homeostatic and defensive cells of the central nervous system (CNS). They undertake numerous functions during development and in adulthood to support and protect the brain through finely regulated communication with other cellular elements of the nervous tissue. In Alzheimer's disease (AD), astrocytes undergo heterogeneous morphological, molecular and functional alterations represented by reactive remodelling, asthenia and loss of function. Reactive astrocytes closely associate with amyloid β (Aβ) plaques and neurofibrillary tangles in advanced AD. The specific contribution of astrocytes to AD could potentially evolve along the disease process and includes alterations in their signalling, interactions with pathological protein aggregates, metabolic and synaptic impairments. In this review, we focus on the purinergic receptor, P2X7R, and discuss the evidence that P2X7R activation contributes to altered astrocyte functions in AD. Expression of P2X7R is increased in AD brain relative to non-demented controls, and animal studies have shown that P2X7R antagonism improves cognitive and synaptic impairments in models of amyloidosis and tauopathy. While P2X7R activation can induce inflammatory signalling pathways, particularly in microglia, we focus here specifically on the contributions of astrocytic P2X7R to synaptic changes and protein aggregate clearance in AD, highlighting cell-specific roles of this purinoceptor activation that could be targeted to slow disease progression.
Collapse
Affiliation(s)
- Paula Beltran-Lobo
- Department of Basic and Clinical Neuroscience, King's College London, Institute of Psychiatry, Psychology and Neuroscience, 5 Cutcombe Road, London, SE5 9RX, U.K
| | - Matthew J Reid
- Department of Basic and Clinical Neuroscience, King's College London, Institute of Psychiatry, Psychology and Neuroscience, 5 Cutcombe Road, London, SE5 9RX, U.K
| | - Maria Jimenez-Sanchez
- Department of Basic and Clinical Neuroscience, King's College London, Institute of Psychiatry, Psychology and Neuroscience, 5 Cutcombe Road, London, SE5 9RX, U.K
| | - Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, U.K
- Achucarro Center for Neuroscience, IKERBASQUE, 48011 Bilbao, Spain
- Department of Forensic Analytical Toxicology, School of Forensic Medicine, China Medical University, Shenyang, China
- Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, LT-01102, Vilnius, Lithuania
| | - Beatriz G Perez-Nievas
- Department of Basic and Clinical Neuroscience, King's College London, Institute of Psychiatry, Psychology and Neuroscience, 5 Cutcombe Road, London, SE5 9RX, U.K
| | - Wendy Noble
- Department of Basic and Clinical Neuroscience, King's College London, Institute of Psychiatry, Psychology and Neuroscience, 5 Cutcombe Road, London, SE5 9RX, U.K
| |
Collapse
|
22
|
I F. The unique neuropathological vulnerability of the human brain to aging. Ageing Res Rev 2023; 87:101916. [PMID: 36990284 DOI: 10.1016/j.arr.2023.101916] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/19/2023] [Accepted: 03/21/2023] [Indexed: 03/30/2023]
Abstract
Alzheimer's disease (AD)-related neurofibrillary tangles (NFT), argyrophilic grain disease (AGD), aging-related tau astrogliopathy (ARTAG), limbic predominant TDP-43 proteinopathy (LATE), and amygdala-predominant Lewy body disease (LBD) are proteinopathies that, together with hippocampal sclerosis, progressively appear in the elderly affecting from 50% to 99% of individuals aged 80 years, depending on the disease. These disorders usually converge on the same subject and associate with additive cognitive impairment. Abnormal Tau, TDP-43, and α-synuclein pathologies progress following a pattern consistent with an active cell-to-cell transmission and abnormal protein processing in the host cell. However, cell vulnerability and transmission pathways are specific for each disorder, albeit abnormal proteins may co-localize in particular neurons. All these alterations are unique or highly prevalent in humans. They all affect, at first, the archicortex and paleocortex to extend at later stages to the neocortex and other regions of the telencephalon. These observations show that the phylogenetically oldest areas of the human cerebral cortex and amygdala are not designed to cope with the lifespan of actual humans. New strategies aimed at reducing the functional overload of the human telencephalon, including optimization of dream repair mechanisms and implementation of artificial circuit devices to surrogate specific brain functions, appear promising.
Collapse
Affiliation(s)
- Ferrer I
- Department of Pathology and Experimental Therapeutics, University of Barcelona, Barcelona, Spain; Emeritus Researcher of the Bellvitge Institute of Biomedical Research (IDIBELL), Barcelona, Spain; Biomedical Research Network of Neurodegenerative Diseases (CIBERNED), Barcelona, Spain; Institute of Neurosciences, University of Barcelona, Barcelona, Spain; Hospitalet de Llobregat, Barcelona, Spain.
| |
Collapse
|
23
|
Common and Specific Marks of Different Tau Strains Following Intra-Hippocampal Injection of AD, PiD, and GGT Inoculum in hTau Transgenic Mice. Int J Mol Sci 2022; 23:ijms232415940. [PMID: 36555581 PMCID: PMC9787745 DOI: 10.3390/ijms232415940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/04/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
Heterozygous hTau mice were used for the study of tau seeding. These mice express the six human tau isoforms, with a high predominance of 3Rtau over 4Rtau. The following groups were assessed: (i) non-inoculated mice aged 9 months (n = 4); (ii) Alzheimer's Disease (AD)-inoculated mice (n = 4); (iii) Globular Glial Tauopathy (GGT)-inoculated mice (n = 4); (iv) Pick's disease (PiD)-inoculated mice (n = 4); (v) control-inoculated mice (n = 4); and (vi) inoculated with vehicle alone (n = 2). AD-inoculated mice showed AT8-immunoreactive neuronal pre-tangles, granular aggregates, and dots in the CA1 region of the hippocampus, dentate gyrus (DG), and hilus, and threads and dots in the ipsilateral corpus callosum. GGT-inoculated mice showed unique or multiple AT8-immunoreactive globular deposits in neurons, occasionally extended to the proximal dendrites. PiD-inoculated mice showed a few loose pre-tangles in the CA1 region, DG, and cerebral cortex near the injection site. Coiled bodies were formed in the corpus callosum in AD-inoculated mice, but GGT-inoculated mice lacked globular glial inclusions. Tau deposits in inoculated mice co-localized active kinases p38-P and SAPK/JNK-P, thus suggesting active phosphorylation of the host tau. Tau deposits were absent in hTau mice inoculated with control homogenates and vehicle alone. Deposits in AD-inoculated hTau mice contained 3Rtau and 4Rtau; those in GGT-inoculated mice were mainly stained with anti-4Rtau antibodies, but a small number of deposits contained 3Rtau. Deposits in PiD-inoculated mice were stained with anti-3Rtau antibodies, but rare neuronal, thread-like, and dot-like deposits showed 4Rtau immunoreactivity. These findings show that tau strains produce different patterns of active neuronal seeding, which also depend on the host tau. Unexpected 3Rtau and 4Rtau deposits after inoculation of homogenates from 4R and 3R tauopathies, respectively, suggests the regulation of exon 10 splicing of the host tau during the process of seeding, thus modulating the plasticity of the cytoskeleton.
Collapse
|
24
|
Mahakud AK, Shaikh J, Rifa Iqbal VV, Gupta A, Tiwari A, Saleem M. Amyloids on Membrane Interfaces: Implications for Neurodegeneration. J Membr Biol 2022; 255:705-722. [PMID: 35670831 DOI: 10.1007/s00232-022-00245-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 05/12/2022] [Indexed: 12/24/2022]
Abstract
Membrane interfaces are vital for various cellular processes, and their involvement in neurodegenerative disorders such as Alzheimer's and Parkinson's disease has taken precedence in recent years. The amyloidogenic proteins associated with neurodegenerative diseases interact with the neuronal membrane through various means, which has implications for both the onset and progression of the disease. The parameters that regulate the interaction between the membrane and the amyloids remain poorly understood. The review focuses on the various aspects of membrane interactions of amyloids, particularly amyloid-β (Aβ) peptides and Tau involved in Alzheimer's and α-synuclein involved in Parkinson's disease. The genetic, cell biological, biochemical, and biophysical studies that form the basis for our current understanding of the membrane interactions of Aβ peptides, Tau, and α-synuclein are discussed.
Collapse
Affiliation(s)
- Amaresh Kumar Mahakud
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India.,Homi Bhabha National Institute, Mumbai, India
| | - Jafarulla Shaikh
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India.,Homi Bhabha National Institute, Mumbai, India
| | - V V Rifa Iqbal
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India.,Homi Bhabha National Institute, Mumbai, India
| | - Abhinav Gupta
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India.,Homi Bhabha National Institute, Mumbai, India
| | - Anuj Tiwari
- Department of Life Sciences, National Institute of Technology, Rourkela, India
| | - Mohammed Saleem
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India. .,Homi Bhabha National Institute, Mumbai, India.
| |
Collapse
|
25
|
Zhu Y, Gandy L, Zhang F, Liu J, Wang C, Blair LJ, Linhardt RJ, Wang L. Heparan Sulfate Proteoglycans in Tauopathy. Biomolecules 2022; 12:1792. [PMID: 36551220 PMCID: PMC9776397 DOI: 10.3390/biom12121792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 11/28/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022] Open
Abstract
Tauopathies are a class of neurodegenerative diseases, including Alzheimer's disease, and are characterized by intraneuronal tau inclusion in the brain and the patient's cognitive decline with obscure pathogenesis. Heparan sulfate proteoglycans, a major type of extracellular matrix, have been believed to involve in tauopathies. The heparan sulfate proteoglycans co-deposit with tau in Alzheimer's patient brain, directly bind to tau and modulate tau secretion, internalization, and aggregation. This review summarizes the current understanding of the functions and the modulated molecular pathways of heparan sulfate proteoglycans in tauopathies, as well as the implication of dysregulated heparan sulfate proteoglycan expression in tau pathology and the potential of targeting heparan sulfate proteoglycan-tau interaction as a novel therapeutic option.
Collapse
Affiliation(s)
- Yanan Zhu
- Department of Molecular Pharmacology & Physiology, Byrd Alzheimer’s Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Lauren Gandy
- Center for Biotechnology and Interdisciplinary Studies, Department of Chemistry and Chemical Biology, Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Fuming Zhang
- Center for Biotechnology and Interdisciplinary Studies, Department of Chemistry and Chemical Biology, Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Jian Liu
- Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Chunyu Wang
- Center for Biotechnology and Interdisciplinary Studies, Department of Chemistry and Chemical Biology, Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Laura J. Blair
- Department of Molecular Medicine, Byrd Alzheimer’s Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33613, USA
| | - Robert J. Linhardt
- Center for Biotechnology and Interdisciplinary Studies, Department of Chemistry and Chemical Biology, Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Lianchun Wang
- Department of Molecular Pharmacology & Physiology, Byrd Alzheimer’s Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| |
Collapse
|
26
|
Natale F, Fusco S, Grassi C. Dual role of brain-derived extracellular vesicles in dementia-related neurodegenerative disorders: cargo of disease spreading signals and diagnostic-therapeutic molecules. Transl Neurodegener 2022; 11:50. [PMID: 36437458 PMCID: PMC9701396 DOI: 10.1186/s40035-022-00326-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 11/09/2022] [Indexed: 11/28/2022] Open
Abstract
Neurodegenerative disorders are one of the most common causes of disability and represent 6.3% of the global burden of disease. Among them, Alzheimer's, Parkinson's, and Huntington's diseases cause cognitive decline, representing the most disabling symptom on both personal and social levels. The molecular mechanisms underlying the onset and progression of dementia are still poorly understood, and include secretory factors potentially affecting differentiated neurons, glial cells and neural stem cell niche. In the last decade, much attention has been devoted to exosomes as novel carriers of information exchanged among both neighbouring and distant cells. These vesicles can be generated and internalized by different brain cells including neurons, neural stem cells, astrocytes, and microglia, thereby affecting neural plasticity and cognitive functions in physiological and pathological conditions. Here, we review data on the roles of exosomes as carriers of bioactive molecules potentially involved in the pathogenesis of neurodegenerative disorders and detectable in biological fluids as biomarkers of dementia. We also discuss the experimental evidence of the therapeutic potential of stem cell-derived vesicles in experimental models of neurodegeneration-dependent cognitive decline.
Collapse
Affiliation(s)
- Francesca Natale
- grid.8142.f0000 0001 0941 3192Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy ,grid.414603.4Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Salvatore Fusco
- grid.8142.f0000 0001 0941 3192Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy ,grid.414603.4Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Claudio Grassi
- grid.8142.f0000 0001 0941 3192Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy ,grid.414603.4Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| |
Collapse
|
27
|
Hier DB, Azizi S, Thimgan MS, Wunsch DC. Tau kinetics in Alzheimer's disease. Front Aging Neurosci 2022; 14:1055170. [PMID: 36437992 PMCID: PMC9682289 DOI: 10.3389/fnagi.2022.1055170] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 10/27/2022] [Indexed: 07/20/2023] Open
Abstract
The cytoskeletal protein tau is implicated in the pathogenesis of Alzheimer's disease which is characterized by intra-neuronal neurofibrillary tangles containing abnormally phosphorylated insoluble tau. Levels of soluble tau are elevated in the brain, the CSF, and the plasma of patients with Alzheimer's disease. To better understand the causes of these elevated levels of tau, we propose a three-compartment kinetic model (brain, CSF, and plasma). The model assumes that the synthesis of tau follows zero-order kinetics (uncorrelated with compartmental tau levels) and that the release, absorption, and clearance of tau is governed by first-order kinetics (linearly related to compartmental tau levels). Tau that is synthesized in the brain compartment can be released into the interstitial fluid, catabolized, or retained in neurofibrillary tangles. Tau released into the interstitial fluid can mix with the CSF and eventually drain to the plasma compartment. However, losses of tau in the drainage pathways may be significant. The kinetic model estimates half-life of tau in each compartment (552 h in the brain, 9.9 h in the CSF, and 10 h in the plasma). The kinetic model predicts that an increase in the neuronal tau synthesis rate or a decrease in tau catabolism rate best accounts for observed increases in tau levels in the brain, CSF, and plasma found in Alzheimer's disease. Furthermore, the model predicts that increases in brain half-life of tau in Alzheimer's disease should be attributed to decreased tau catabolism and not to increased tau synthesis. Most clearance of tau in the neuron occurs through catabolism rather than release to the CSF compartment. Additional experimental data would make ascertainment of the model parameters more precise.
Collapse
Affiliation(s)
- Daniel B. Hier
- Applied Computational Intelligence Laboratory, Department of Electrical & Computer Engineering, Missouri University of Science & Technology, Rolla, MO, United States
- Department of Neurology and Rehabilitation, University of Illinois at Chicago, Chicago, IL, United States
| | - Sima Azizi
- Applied Computational Intelligence Laboratory, Department of Electrical & Computer Engineering, Missouri University of Science & Technology, Rolla, MO, United States
| | - Matthew S. Thimgan
- Department of Biological Sciences, Missouri University of Science & Technology, Rolla, MO, United States
| | - Donald C. Wunsch
- Applied Computational Intelligence Laboratory, Department of Electrical & Computer Engineering, Missouri University of Science & Technology, Rolla, MO, United States
- ECCS Division, National Science Foundation, Alexandria, VA, United States
| |
Collapse
|
28
|
Lolicato F, Saleppico R, Griffo A, Meyer A, Scollo F, Pokrandt B, Müller HM, Ewers H, Hähl H, Fleury JB, Seemann R, Hof M, Brügger B, Jacobs K, Vattulainen I, Nickel W. Cholesterol promotes clustering of PI(4,5)P2 driving unconventional secretion of FGF2. J Biophys Biochem Cytol 2022; 221:213511. [PMID: 36173379 PMCID: PMC9526255 DOI: 10.1083/jcb.202106123] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/22/2022] [Accepted: 08/30/2022] [Indexed: 11/22/2022] Open
Abstract
FGF2 is a cell survival factor involved in tumor-induced angiogenesis that is secreted through an unconventional secretory pathway based upon direct protein translocation across the plasma membrane. Here, we demonstrate that both PI(4,5)P2-dependent FGF2 recruitment at the inner plasma membrane leaflet and FGF2 membrane translocation into the extracellular space are positively modulated by cholesterol in living cells. We further revealed cholesterol to enhance FGF2 binding to PI(4,5)P2-containing lipid bilayers. Based on extensive atomistic molecular dynamics (MD) simulations and membrane tension experiments, we proposed cholesterol to modulate FGF2 binding to PI(4,5)P2 by (i) increasing head group visibility of PI(4,5)P2 on the membrane surface, (ii) increasing avidity by cholesterol-induced clustering of PI(4,5)P2 molecules triggering FGF2 oligomerization, and (iii) increasing membrane tension facilitating the formation of lipidic membrane pores. Our findings have general implications for phosphoinositide-dependent protein recruitment to membranes and explain the highly selective targeting of FGF2 toward the plasma membrane, the subcellular site of FGF2 membrane translocation during unconventional secretion of FGF2.
Collapse
Affiliation(s)
- Fabio Lolicato
- Heidelberg University Biochemistry Center, Heidelberg, Germany.,Department of Physics, University of Helsinki, Helsinki, Finland
| | | | - Alessandra Griffo
- Department of Experimental Physics, Saarland University, Saarbrücken, Germany.,Biophysical Engineering Group, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Annalena Meyer
- Heidelberg University Biochemistry Center, Heidelberg, Germany
| | - Federica Scollo
- Department of Biophysical Chemistry, J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Bianca Pokrandt
- Heidelberg University Biochemistry Center, Heidelberg, Germany
| | | | - Helge Ewers
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Hendrik Hähl
- Department of Experimental Physics, Saarland University, Saarbrücken, Germany
| | | | - Ralf Seemann
- Department of Experimental Physics, Saarland University, Saarbrücken, Germany
| | - Martin Hof
- Department of Biophysical Chemistry, J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Britta Brügger
- Heidelberg University Biochemistry Center, Heidelberg, Germany
| | - Karin Jacobs
- Department of Experimental Physics, Saarland University, Saarbrücken, Germany.,Max Planck School Matter to Life, Heidelberg, Germany
| | - Ilpo Vattulainen
- Department of Physics, University of Helsinki, Helsinki, Finland
| | - Walter Nickel
- Heidelberg University Biochemistry Center, Heidelberg, Germany
| |
Collapse
|
29
|
Polanco JC, Götz J. Exosomal and vesicle-free tau seeds-propagation and convergence in endolysosomal permeabilization. FEBS J 2022; 289:6891-6907. [PMID: 34092031 DOI: 10.1111/febs.16055] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/19/2021] [Accepted: 06/04/2021] [Indexed: 01/13/2023]
Abstract
In Alzheimer's disease (AD), β-amyloid peptides aggregate to form amyloid plaques, and the microtubule-associated protein tau forms neurofibrillary tangles. However, severity and duration of AD correlate with the stereotypical emergence of tau tangles throughout the brain, suggestive of a gradual region-to-region spreading of pathological tau. The current notion in the field is that misfolded tau seeds propagate transsynaptically and corrupt the proper folding of soluble tau in recipient neurons. This is supported by accumulating evidence showing that in AD, functional connectivity and not proximity predicts the spreading of tau pathology. Tau seeds can be found in two flavors, vesicle-free, that is, naked as in oligomers and fibrils, or encapsulated by membranes of secreted vesicles known as exosomes. Both types of seeds have been shown to propagate between interconnected neurons. Here, we describe potential ways of how their propagation can be controlled in several subcellular compartments by manipulating mechanisms affecting production, neuron-to-neuron transmission, internalization, endosomal escape, and autophagy. We emphasize that although vesicle-free tau seeds and exosomes differ, they share the ability to trigger endolysosomal permeabilization. Such a mechanistic convergence in endolysosomal permeabilization presents itself as a unique opportunity to target both types of tau seeding. We discuss the cellular response to endolysosomal damage that might be key to control permeabilization, and the significant overlap in the seeding mechanism of proteopathic agents other than tau, which suggests that targeting the endolysosomal pathway could pave the way toward developing broad-spectrum treatments for neurodegenerative diseases.
Collapse
Affiliation(s)
- Juan Carlos Polanco
- Clem Jones Centre for Ageing Dementia Research (CJCADR), Queensland Brain Institute (QBI), The University of Queensland, Brisbane, QLD, Australia
| | - Jürgen Götz
- Clem Jones Centre for Ageing Dementia Research (CJCADR), Queensland Brain Institute (QBI), The University of Queensland, Brisbane, QLD, Australia
| |
Collapse
|
30
|
Pilliod J, Gélinas-Faucher M, Leclerc N. Unconventional secretion of tau by VAMP8 impacts its intra- and extracellular cleavage. Front Cell Dev Biol 2022; 10:912118. [PMID: 36313558 PMCID: PMC9605769 DOI: 10.3389/fcell.2022.912118] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 09/20/2022] [Indexed: 11/18/2022] Open
Abstract
In Alzheimer’s disease, Tau, a microtubule-associated protein, becomes hyperphosphorylated, detaches from microtubules, and accumulates in the somato-dendritic compartment where it forms insoluble aggregates. Tau also accumulates in the CSF of patients indicating that it is released by neurons. Consistent with this, several laboratories including ours have shown that Tau is secreted by neurons through unconventional secretory pathways. Recently, we reported that VAMP8, an R-SNARE found on late endosomes, increased Tau secretion and that secreted Tau was cleaved at the C-terminal. In the present study, we examined whether the increase of Tau secretion by VAMP8 affected its intra- and extracellular cleavage. Upon VAMP8 overexpression, an increase of Tau cleaved by caspase-3 in the cell lysate and medium was observed. This was correlated to an increase of active caspase-3 in the cell lysate and medium. Using a Tau mutant not cleavable by caspase-3, we demonstrated that Tau cleavage by caspase-3 was not necessary for its secretion upon VAMP8 overexpression. By adding recombinant Tau to the culture medium, we demonstrated that extracellular Tau cleavage by caspase-3 could occur because of the release of active caspase-3, which was the highest when VAMP8 was overexpressed. When cleavage of Tau by caspase-3 was prevented by using a non-cleavable mutant, secreted Tau was still cleaved at the C-terminal, the asparagine N410 contributing to it. Lastly, we demonstrated that N-terminal of Tau regulated the secretion pattern of a Tau fragment containing the microtubule-binding domain and the C-terminal of Tau upon VAMP8 overexpression. Collectively, the above observations indicate that VAMP8 overexpression affects the intra- and extracellular cleavage pattern of Tau.
Collapse
Affiliation(s)
- Julie Pilliod
- Research Center of the University of Montreal Hospital (CRCHUM), Montréal, QC, Canada
| | - Maude Gélinas-Faucher
- Research Center of the University of Montreal Hospital (CRCHUM), Montréal, QC, Canada
| | - Nicole Leclerc
- Research Center of the University of Montreal Hospital (CRCHUM), Montréal, QC, Canada
- Département de Neurosciences, Faculté de Médecine, Université de Montréal, Montréal, QC, Canada
- *Correspondence: Nicole Leclerc,
| |
Collapse
|
31
|
Opportunities and challenges in delivering biologics for Alzheimer's disease by low-intensity ultrasound. Adv Drug Deliv Rev 2022; 189:114517. [PMID: 36030018 DOI: 10.1016/j.addr.2022.114517] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 08/15/2022] [Accepted: 08/19/2022] [Indexed: 01/24/2023]
Abstract
Low-intensity ultrasound combined with intravenously injected microbubbles (US+MB) is a novel treatment modality for brain disorders, including Alzheimer's disease (AD), safely and transiently allowing therapeutic agents to overcome the blood-brain barrier (BBB) that constitutes a major barrier for therapeutic agents. Here, we first provide an update on immunotherapies in AD and how US+MB has been applied to AD mouse models and in clinical trials, considering the ultrasound and microbubble parameter space. In the second half of the review, we compare different in vitro BBB models and discuss strategies for combining US+MB with BBB modulators (targeting molecules such as claudin-5), and highlight the insight provided by super-resolution microscopy. Finally, we conclude with a short discussion on how in vitro findings can inform the design of animal studies, and how the insight gained may aid treatment optimization in the clinical ultrasound space.
Collapse
|
32
|
Guillemain G, Lacapere JJ, Khemtemourian L. Targeting hIAPP fibrillation: A new paradigm to prevent β-cell death? BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:184002. [PMID: 35868406 DOI: 10.1016/j.bbamem.2022.184002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/20/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
Loss of pancreatic β-cell mass is deleterious for type 2 diabetes patients since it reduces insulin production, critical for glucose homeostasis. The main research axis developed over the last few years was to generate new pancreatic β-cells or to transplant pancreatic islets as occurring for some specific type 1 diabetes patients. We evaluate here a new paradigm consisting in preservation of β-cells by prevention of human islet amyloid polypeptide (hIAPP) oligomers and fibrils formation leading to pancreatic β-cell death. We review the hIAPP physiology and the pathology that contributes to β-cell destruction, deciphering the various cellular steps that could be involved. Recent progress in understanding other amyloidosis such as Aβ, Tau, α-synuclein or prion, involved in neurodegenerative processes linked with inflammation, has opened new research lines of investigations to preserve neuronal cells. We evaluate and estimate their transposition to the pancreatic β-cells preservation. Among them is the control of reactive oxygen species (ROS) production occurring with inflammation and the possible implication of the mitochondrial translocator protein as a diagnostic and therapeutic target. The present review also focuses on other amyloid forming proteins from molecular to physiological and physiopathological points of view that could help to better decipher hIAPP-induced β-cell death mechanisms and to prevent hIAPP fibril formation.
Collapse
Affiliation(s)
- Ghislaine Guillemain
- Sorbonne Université, Institut Hospitalo-Universitaire, Inserm UMR_S938, Institute of Cardio metabolism and Nutrition (ICAN), Centre de recherche de St-Antoine (CRSA), 27 rue de Chaligny, F-75012 Paris, France.
| | - Jean-Jacques Lacapere
- Sorbonne Université, Ecole Normale Supérieure, PSL University, CNRS UMR 7203, Laboratoire des BioMolécules (LBM), 4 place Jussieu, F-75005 Paris, France.
| | - Lucie Khemtemourian
- CBMN, CNRS UMR 5248, IPB, Univ. Bordeaux, Allée Geoffroy Saint-Hilaire, F-33600 Pessac, France.
| |
Collapse
|
33
|
Zhu B, Liu Y, Hwang S, Archuleta K, Huang H, Campos A, Murad R, Piña-Crespo J, Xu H, Huang TY. Trem2 deletion enhances tau dispersion and pathology through microglia exosomes. Mol Neurodegener 2022; 17:58. [PMID: 36056435 PMCID: PMC9438095 DOI: 10.1186/s13024-022-00562-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 08/14/2022] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is a neurodegenerative disorder that manifests sequential Aβ and tau brain pathology with age-dependent onset. Variants in the microglial immune receptor TREM2 are associated with enhanced risk of onset in sporadic Alzheimer's disease (AD). While recent studies suggest TREM2 dysfunction can aggravate tau pathology, mechanisms underlying TREM2-dependent modulation of tau pathology remains elusive. METHODS Here, we characterized differences in progressive tau spreading from the medial entorhinal cortex (MEC) to the hippocampus in wildtype (WT) and Trem2 knockout (KO) mice by injection of AAV-P301L tau into the MEC, and correlated changes in hippocampal tau histopathology with spatial and fear memory. We also compared effects of intraneuronal dispersion between cultured microglia and neurons using a microfluidic dispersion assay, analyzed differences in microglial tau trafficking following uptake, and quantified exosomal tau secretion and pathogenicity from purified WT and Trem2 KO exosomes. RESULTS Trem2 deletion in mice (Trem2 KO) can enhance tau spreading from the medial entorhinal cortex (MEC) to the hippocampus, which coincides with impaired synaptic function and memory behavior. Trem2 deletion in microglia enhances intraneuronal dispersion of tau in vitro between neuronal layers cultured in a microfluidic chamber, and the presence of exosome inhibitors can significantly reduce tau in exosomes and extracellular media from tau-loaded microglia. Although microglial Trem2 deletion has no effect on tau uptake, Trem2 deletion enhances distribution to endosomal and cellular pre-exosomal compartments following internalization. Trem2 deletion has little effect on exosome size, however, proteomic analysis indicates that Trem2 deletion can modulate changes in the microglial proteomic landscape with tau and LPS/ATP treatment conditions associated with exosome induction. Furthermore, exosomes from Trem2 KO microglia show elevated tau levels, and feature enhanced tau-seeding capacity in a tau FRET reporter line compared to exosomes from WT microglia. CONCLUSION Together, our results reveal a role for Trem2 in suppressing exosomal tau pathogenicity, and demonstrates that Trem2 deletion can enhance tau trafficking, distribution and seeding through microglial exosomes.
Collapse
Affiliation(s)
- Bing Zhu
- grid.479509.60000 0001 0163 8573Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Yan Liu
- grid.479509.60000 0001 0163 8573Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Spring Hwang
- grid.479509.60000 0001 0163 8573Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Kailey Archuleta
- grid.479509.60000 0001 0163 8573Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Huijie Huang
- grid.479509.60000 0001 0163 8573Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Alex Campos
- grid.479509.60000 0001 0163 8573Proteomics Facility Core, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Rabi Murad
- grid.479509.60000 0001 0163 8573Bioinformatics Core, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Juan Piña-Crespo
- grid.479509.60000 0001 0163 8573Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| | - Huaxi Xu
- Present address: Institute for Brain Science and Disease, Chongqing Medical University, Chongqing, China.
| | - Timothy Y. Huang
- grid.479509.60000 0001 0163 8573Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 USA
| |
Collapse
|
34
|
Padmanabhan P, Kneynsberg A, Cruz E, Amor R, Sibarita JB, Götz J. Single-molecule imaging reveals Tau trapping at nanometer-sized dynamic hot spots near the plasma membrane that persists after microtubule perturbation and cholesterol depletion. EMBO J 2022; 41:e111265. [PMID: 36004506 PMCID: PMC9531302 DOI: 10.15252/embj.2022111265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 11/25/2022] Open
Abstract
Accumulation of aggregates of the microtubule‐binding protein Tau is a pathological hallmark of Alzheimer's disease. While Tau is thought to primarily associate with microtubules, it also interacts with and localizes to the plasma membrane. However, little is known about how Tau behaves and organizes at the plasma membrane of live cells. Using quantitative, single‐molecule imaging, we show that Tau exhibits spatial and kinetic heterogeneity near the plasma membrane of live cells, resulting in the formation of nanometer‐sized hot spots. The hot spots lasted tens of seconds, much longer than the short dwell time (∼ 40 ms) of Tau on microtubules. Pharmacological and biochemical disruption of Tau/microtubule interactions did not prevent hot spot formation, suggesting that these are different from the reported Tau condensation on microtubules. Although cholesterol removal has been shown to reduce Tau pathology, its acute depletion did not affect Tau hot spot dynamics. Our study identifies an intrinsic dynamic property of Tau near the plasma membrane that may facilitate the formation of assembly sites for Tau to assume its physiological and pathological functions.
Collapse
Affiliation(s)
- Pranesh Padmanabhan
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Andrew Kneynsberg
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Esteban Cruz
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Rumelo Amor
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Jean-Baptiste Sibarita
- Université de Bordeaux, Interdisciplinary Institute for Neuroscience, UMR, Bordeaux, France
| | - Jürgen Götz
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| |
Collapse
|
35
|
Aβ and Tau Interact with Metal Ions, Lipid Membranes and Peptide-Based Amyloid Inhibitors: Are These Common Features Relevant in Alzheimer’s Disease? Molecules 2022; 27:molecules27165066. [PMID: 36014310 PMCID: PMC9414153 DOI: 10.3390/molecules27165066] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/04/2022] [Accepted: 08/05/2022] [Indexed: 12/13/2022] Open
Abstract
In the last two decades, the amyloid hypothesis, i.e., the abnormal accumulation of toxic Aβ assemblies in the brain, has been considered the mainstream concept sustaining research in Alzheimer’s Disease (AD). However, the course of cognitive decline and AD development better correlates with tau accumulation rather than amyloid peptide deposition. Moreover, all clinical trials of amyloid-targeting drug candidates have been unsuccessful, implicitly suggesting that the amyloid hypothesis needs significant amendments. Accumulating evidence supports the existence of a series of potentially dangerous relationships between Aβ oligomeric species and tau protein in AD. However, the molecular determinants underlying pathogenic Aβ/tau cross interactions are not fully understood. Here, we discuss the common features of Aβ and tau molecules, with special emphasis on: (i) the critical role played by metal dyshomeostasis in promoting both Aβ and tau aggregation and oxidative stress, in AD; (ii) the effects of lipid membranes on Aβ and tau (co)-aggregation at the membrane interface; (iii) the potential of small peptide-based inhibitors of Aβ and tau misfolding as therapeutic tools in AD. Although the molecular mechanism underlying the direct Aβ/tau interaction remains largely unknown, the arguments discussed in this review may help reinforcing the current view of a synergistic Aβ/tau molecular crosstalk in AD and stimulate further research to mechanism elucidation and next-generation AD therapeutics.
Collapse
|
36
|
Seitkazina A, Kim KH, Fagan E, Sung Y, Kim YK, Lim S. The Fate of Tau Aggregates Between Clearance and Transmission. Front Aging Neurosci 2022; 14:932541. [PMID: 35923541 PMCID: PMC9339952 DOI: 10.3389/fnagi.2022.932541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/22/2022] [Indexed: 11/30/2022] Open
Abstract
Neuronal accumulation of mis-folded tau is the pathological hallmark of multiple neurodegenerative disorders, including Alzheimer’s disease. Distinct from amyloid plaques, which appear simultaneously throughout the brain, tau pathology develops first in a specific brain region and then propagates to neuroanatomically connected brain regions, exacerbating the disease. Due to the implication in disease progression, prevention of tau transmission is recognized as an important therapeutic strategy that can halt disease progression in the brain. Recently, accumulating studies have demonstrated diverse cellular mechanisms associated with cell-to-cell transmission of tau. Once transmitted, mis-folded tau species act as a prion-like seed for native tau aggregation in the recipient neuron. In this review, we summarize the diverse cellular mechanisms associated with the secretion and uptake of tau, and highlight tau-trafficking receptors, which mediate tau clearance or cell-to-cell tau transmission.
Collapse
Affiliation(s)
- Assel Seitkazina
- Convergence Research Center for Brain Science, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Division of Bio-Medical Science and Technology, Korea Institute of Science and Technology (KIST) School, University of Science and Technology (UST), Seoul, South Korea
| | - Kyu Hyeon Kim
- Convergence Research Center for Brain Science, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Division of Bio-Medical Science and Technology, Korea Institute of Science and Technology (KIST) School, University of Science and Technology (UST), Seoul, South Korea
| | - Erin Fagan
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA, United States
| | - Yoonsik Sung
- Convergence Research Center for Brain Science, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Division of Bio-Medical Science and Technology, Korea Institute of Science and Technology (KIST) School, University of Science and Technology (UST), Seoul, South Korea
| | - Yun Kyung Kim
- Convergence Research Center for Brain Science, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Division of Bio-Medical Science and Technology, Korea Institute of Science and Technology (KIST) School, University of Science and Technology (UST), Seoul, South Korea
- *Correspondence: Yun Kyung Kim,
| | - Sungsu Lim
- Convergence Research Center for Brain Science, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Sungsu Lim,
| |
Collapse
|
37
|
Ahat E, Bui S, Zhang J, da Veiga Leprevost F, Sharkey L, Reid W, Nesvizhskii AI, Paulson HL, Wang Y. GRASP55 regulates the unconventional secretion and aggregation of mutant huntingtin. J Biol Chem 2022; 298:102219. [PMID: 35780830 PMCID: PMC9352920 DOI: 10.1016/j.jbc.2022.102219] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 06/19/2022] [Accepted: 06/20/2022] [Indexed: 11/25/2022] Open
Abstract
Recent studies demonstrated that the Golgi reassembly stacking proteins (GRASPs), especially GRASP55, regulate Golgi-independent unconventional secretion of certain cytosolic and transmembrane cargoes; however, the underlying mechanism remains unknown. Here, we surveyed several neurodegenerative disease-related proteins, including mutant huntingtin (Htt-Q74), superoxide dismutase 1 (SOD1), tau, and TAR DNA-binding protein 43 (TDP-43), for unconventional secretion; our results show that Htt-Q74 is most robustly secreted in a GRASP55-dependent manner. Using Htt-Q74 as a model system, we demonstrate that unconventional secretion of Htt is GRASP55 and autophagy dependent and is enhanced under stress conditions such as starvation and endoplasmic reticulum stress. Mechanistically, we show that GRASP55 facilitates Htt secretion by tethering autophagosomes to lysosomes to promote autophagosome maturation and subsequent lysosome secretion and by stabilizing p23/TMED10, a channel for translocation of cytoplasmic proteins into the lumen of the endoplasmic reticulum-Golgi intermediate compartment. Moreover, we found that GRASP55 levels are upregulated by various stresses to facilitate unconventional secretion, whereas inhibition of Htt-Q74 secretion by GRASP55 KO enhances Htt aggregation and toxicity. Finally, comprehensive secretomic analysis identified novel cytosolic cargoes secreted by the same unconventional pathway, including transgelin (TAGLN), multifunctional protein ADE2 (PAICS), and peroxiredoxin-1 (PRDX1). In conclusion, this study defines the pathway of GRASP55-mediated unconventional protein secretion and provides important insights into the progression of Huntington's disease.
Collapse
Affiliation(s)
- Erpan Ahat
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Sarah Bui
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jianchao Zhang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Lisa Sharkey
- Department of Neurology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Whitney Reid
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Alexey I. Nesvizhskii
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Henry L. Paulson
- Department of Neurology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Yanzhuang Wang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA; Department of Neurology, University of Michigan School of Medicine, Ann Arbor, Michigan, USA.
| |
Collapse
|
38
|
Noh SH, Kim YJ, Lee MG. Autophagy-Related Pathways in Vesicular Unconventional Protein Secretion. Front Cell Dev Biol 2022; 10:892450. [PMID: 35774225 PMCID: PMC9237382 DOI: 10.3389/fcell.2022.892450] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 05/26/2022] [Indexed: 12/14/2022] Open
Abstract
Cellular proteins directed to the plasma membrane or released into the extracellular space can undergo a number of different pathways. Whereas the molecular mechanisms that underlie conventional ER-to-Golgi trafficking are well established, those associated with the unconventional protein secretion (UPS) pathways remain largely elusive. A pathway with an emerging role in UPS is autophagy. Although originally known as a degradative process for maintaining intracellular homeostasis, recent studies suggest that autophagy has diverse biological roles besides its disposal function and that it is mechanistically involved in the UPS of various secretory cargos including both leaderless soluble and Golgi-bypassing transmembrane proteins. Here, we summarize current knowledge of the autophagy-related UPS pathways, describing and comparing diverse features in the autophagy-related UPS cargos and autophagy machineries utilized in UPS. Additionally, we also suggest potential directions that further research in this field can take.
Collapse
Affiliation(s)
- Shin Hye Noh
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, South Korea
- *Correspondence: Shin Hye Noh, ; Min Goo Lee,
| | - Ye Jin Kim
- Department of Pharmacology, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Min Goo Lee
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, South Korea
- Department of Pharmacology, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
- *Correspondence: Shin Hye Noh, ; Min Goo Lee,
| |
Collapse
|
39
|
Pei D, Dalbey RE. Membrane Translocation of Folded Proteins. J Biol Chem 2022; 298:102107. [PMID: 35671825 PMCID: PMC9251779 DOI: 10.1016/j.jbc.2022.102107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 05/31/2022] [Accepted: 06/01/2022] [Indexed: 12/01/2022] Open
Abstract
An ever-increasing number of proteins have been shown to translocate across various membranes of bacterial as well as eukaryotic cells in their folded states as a part of physiological and/or pathophysiological processes. Herein we provide an overview of the systems/processes that are established or likely to involve the membrane translocation of folded proteins, such as protein export by the twin-arginine translocation (TAT) system in bacteria and chloroplasts, unconventional protein secretion (UPS) and protein import into the peroxisome in eukaryotes, and the cytosolic entry of proteins (e.g., bacterial toxins) and viruses into eukaryotes. We also discuss the various mechanistic models that have previously been proposed for the membrane translocation of folded proteins including pore/channel formation, local membrane disruption, membrane thinning, and transport by membrane vesicles. Finally, we introduce a newly discovered vesicular transport mechanism, vesicle budding and collapse (VBC), and present evidence that VBC may represent a unifying mechanism that drives some (and potentially all) of folded protein translocation processes.
Collapse
Affiliation(s)
- Dehua Pei
- Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12(th) Avenue, Columbus, OH 43210.
| | - Ross E Dalbey
- Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12(th) Avenue, Columbus, OH 43210.
| |
Collapse
|
40
|
Lee J, Xu Y, Ye Y. Safeguarding Lysosomal Homeostasis by DNAJC5/CSPα-Mediated Unconventional Protein Secretion and Endosomal Microautophagy. Front Cell Dev Biol 2022; 10:906453. [PMID: 35620055 PMCID: PMC9127312 DOI: 10.3389/fcell.2022.906453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 04/25/2022] [Indexed: 11/24/2022] Open
Abstract
Neuronal ceroid lipofuscinosis (NCL) is a collection of genetically inherited neurological disorders characterized by vision loss, seizure, brain death, and premature lethality. At the cellular level, a key pathologic hallmark of NCL is the build-up of autofluorescent storage materials (AFSM) in lysosomes of both neurons and non-neuronal cells. Molecular dissection of the genetic lesions underlying NCLs has shed significant insights into how disruption of lysosomal homeostasis may lead to lipofuscin accumulation and NCLs. Intriguingly, recent studies on DNAJC5/CSPα, a membrane associated HSC70 co-chaperone, have unexpectedly linked lipofuscin accumulation to two intimately coupled protein quality control processes at endolysosomes. This review discusses how deregulation of unconventional protein secretion and endosomal microautophagy (eMI) contributes to lipofuscin accumulation and neurodegeneration.
Collapse
Affiliation(s)
- Juhyung Lee
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Yue Xu
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Yihong Ye
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, United States
| |
Collapse
|
41
|
Unconventional secretion mediated by direct protein self-translocation across the plasma membranes of mammalian cells. Trends Biochem Sci 2022; 47:699-709. [PMID: 35490075 DOI: 10.1016/j.tibs.2022.04.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/22/2022] [Accepted: 04/01/2022] [Indexed: 12/17/2022]
Abstract
In recent years, a surprisingly complex picture emerged about endoplasmic reticulum (ER)/Golgi-independent secretory pathways, and several routes have been discovered that differ with regard to their molecular mechanisms and machineries. Fibroblast growth factor 2 (FGF2) is secreted by a pathway of unconventional protein secretion (UPS) that is based on direct self-translocation across the plasma membrane. Building on previous research, a component of this process has been identified to be glypican-1 (GPC1), a GPI-anchored heparan sulfate proteoglycan located on cell surfaces. These findings not only shed light on the molecular mechanism underlying this process but also reveal an intimate relationship between FGF2 and GPC1 that might be of critical relevance for the prominent roles they both have in tumor progression and metastasis.
Collapse
|
42
|
Lolicato F, Nickel W. A Role for Liquid-Ordered Plasma Membrane Nanodomains Coordinating the Unconventional Secretory Pathway of Fibroblast Growth Factor 2? Front Cell Dev Biol 2022; 10:864257. [PMID: 35433697 PMCID: PMC9010882 DOI: 10.3389/fcell.2022.864257] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 02/18/2022] [Indexed: 11/22/2022] Open
Abstract
Fibroblast growth factor 2 (FGF2) is a tumor cell survival factor that belongs to a subgroup of extracellular proteins lacking N-terminal signal peptides. Whereas this phenomenon was already recognized in the early 1990s, detailed insights into the molecular mechanisms underlying alternative pathways of protein secretion from eukaryotic cells were obtained only recently. Today, we know about a number of alternative secretory mechanisms, collectively termed unconventional protein secretion (UPS). FGF2 belongs to a subgroup of cargo proteins secreted by direct translocation across the plasma membrane. This feature has been classified as type I UPS and is shared with other unconventionally secreted proteins, such as HIV-Tat and Tau. FGF2 translocation across the membrane is initiated through sequential interactions with the Na,K-ATPase, Tec kinase, and phosphoinositide PI(4,5)P2 at the inner plasma membrane leaflet. Whereas the first two are auxiliary factors of this pathway, the interaction of FGF2 with PI(4,5)P2 triggers the core mechanism of FGF2 membrane translocation. It is based on a lipidic membrane pore that is formed by PI(4,5)P2-induced oligomerization of FGF2. Membrane-inserted FGF2 oligomers are recognized as translocation intermediates that are resolved at the outer plasma membrane leaflet by glypican-1, a heparan sulfate proteoglycan that captures and disassembles FGF2 oligomers on cell surfaces. Here, we discuss recent findings suggesting the molecular machinery mediating FGF2 membrane translocation to be highly organized in liquid-ordered plasma membrane nanodomains, the core process underlying this unusual pathway of protein secretion.
Collapse
|
43
|
Delivery of Intravenously Administered Antibodies Targeting Alzheimer’s Disease-Relevant Tau Species into the Brain Based on Receptor-Mediated Transcytosis. Pharmaceutics 2022; 14:pharmaceutics14020411. [PMID: 35214143 PMCID: PMC8876001 DOI: 10.3390/pharmaceutics14020411] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 01/28/2022] [Accepted: 02/10/2022] [Indexed: 01/23/2023] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disease that causes memory loss, cognitive decline, and eventually dementia. The etiology of AD and its pathological mechanisms remain unclear due to its complex pathobiology. At the same time, the number of patients with AD is increasing worldwide. However, no therapeutic agents for AD are currently available for definitive care. Several phase 3 clinical trials using agents targeting amyloid β (Aβ) and its related molecules have failed, with the exception of aducanumab, an anti-Aβ monoclonal antibody (mAb), clinically approved by the US Food and Drug Administration in 2021, which could be modified for AD drug development due to controversial approval. Neurofibrillary tangles (NFTs) composed of tau rather than senile plaques composed of Aβ are correlated with AD pathogenesis. Moreover, Aβ and tau pathologies initially proceed independently. At a certain point in the progression of AD symptoms, the Aβ pathology is involved in the alteration and spreading of the tau pathology. Therefore, tau-targeting therapies have attracted the attention of pharmaceutical scientists, as well as Aβ-targeting therapies. In this review, I introduce the implementations and potential of AD immunotherapy using intravenously administered anti-tau and anti-receptor bispecific mAbs. These cross the blood-brain barrier (BBB) based on receptor-mediated transcytosis and are subsequently cleared by microglia based on Fc-mediated endocytosis after binding to tau and lysosomal degradation.
Collapse
|
44
|
Leroux E, Perbet R, Caillierez R, Richetin K, Lieger S, Espourteille J, Bouillet T, Bégard S, Danis C, Loyens A, Toni N, Déglon N, Deramecourt V, Schraen-Maschke S, Buée L, Colin M. Extracellular vesicles: Major actors of heterogeneity in tau spreading among human tauopathies. Mol Ther 2022; 30:782-797. [PMID: 34563677 PMCID: PMC8821971 DOI: 10.1016/j.ymthe.2021.09.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 07/12/2021] [Accepted: 09/20/2021] [Indexed: 02/04/2023] Open
Abstract
Tauopathies are neurodegenerative diseases characterized by tau inclusions in brain cells. Seed-competent tau species have been suggested to spread from cell to cell in a stereotypical manner, indicating that this may involve a prion-like mechanism. Although the intercellular mechanisms of transfer are unclear, extracellular vesicles (EVs) could be potential shuttles. We assessed this in humans by preparing vesicles from fluids (brain-derived enriched EVs [BD-EVs]). These latter were isolated from different brain regions in various tauopathies, and their seeding potential was assessed in vitro and in vivo. We observed considerable heterogeneity among tauopathies and brain regions. The most striking evidence was coming mainly from Alzheimer's disease where the BD-EVs clearly contain pathological species that can induce tau lesions in vivo. The results support the hypothesis that BD-EVs participate in the prion-like propagation of tau pathology among tauopathies, and there may be implications for diagnostic and therapeutic strategies.
Collapse
Affiliation(s)
- Elodie Leroux
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | - Romain Perbet
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | - Raphaëlle Caillierez
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | - Kevin Richetin
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, 1011 Lausanne, Switzerland,Lausanne University Hospital (CHUV) and University of Lausanne, Neuroscience Research Center (CRN), Laboratory of Cellular and Molecular Neurotherapies, 1011 Lausanne, Switzerland,Lausanne University Hospital (CHUV) and University of Lausanne, Department of Clinical Neuroscience (DNC), Laboratory of Cellular and Molecular Neurotherapies, 1011 Lausanne, Switzerland
| | - Sarah Lieger
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | - Jeanne Espourteille
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, 1011 Lausanne, Switzerland
| | - Thomas Bouillet
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | - Séverine Bégard
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | - Clément Danis
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | - Anne Loyens
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | - Nicolas Toni
- Department of Psychiatry, Center for Psychiatric Neurosciences, Lausanne University Hospital (CHUV) and University of Lausanne, 1011 Lausanne, Switzerland
| | - Nicole Déglon
- Lausanne University Hospital (CHUV) and University of Lausanne, Neuroscience Research Center (CRN), Laboratory of Cellular and Molecular Neurotherapies, 1011 Lausanne, Switzerland,Lausanne University Hospital (CHUV) and University of Lausanne, Department of Clinical Neuroscience (DNC), Laboratory of Cellular and Molecular Neurotherapies, 1011 Lausanne, Switzerland
| | - Vincent Deramecourt
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France
| | | | - Luc Buée
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France,Corresponding author: Luc Buée, PhD, Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, Bâtiment Biserte, rue Polonovski, 59045 Lille Cedex, France.
| | - Morvane Colin
- Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, 59000 Lille, France,Corresponding author: Morvane Colin, Université de Lille, INSERM, CHU-Lille, Lille Neuroscience & Cognition, Bâtiment Biserte, rue Polonovski, 59045 Lille Cedex, France.
| |
Collapse
|
45
|
Song L, Oseid DE, Wells EA, Coaston T, Robinson AS. Heparan Sulfate Proteoglycans (HSPGs) Serve as the Mediator Between Monomeric Tau and Its Subsequent Intracellular ERK1/2 Pathway Activation. J Mol Neurosci 2022; 72:772-791. [PMID: 35040015 PMCID: PMC8763444 DOI: 10.1007/s12031-021-01943-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 11/06/2021] [Indexed: 12/15/2022]
Abstract
The conversion of soluble tau protein to insoluble, hyperphosphorylated neurofibrillary tangles (NFTs) is a major hallmark leading to neuronal death observed in neurodegenerative tauopathies. Unlike NFTs, the involvement of monomeric tau in the progression of tau pathology has been less investigated. Using live-cell confocal microscopy and flow cytometry, we demonstrate that soluble 0N4R monomers were rapidly endocytosed by SH-SY5Y and C6 glioma cells via actin-dependent macropinocytosis. Further, cellular endocytosis of monomeric tau has been demonstrated to be HSPG-dependent, as shown in C6 glial cells with genetic knockouts of xylosyltransferase-1—a key enzyme in HSPG synthesis—with a reduced level of tau uptake. Tau internalization subsequently triggers ERK1/2 activation and therefore, the upregulation of IL-6 and IL-1β. The role of ERK1/2 in regulating the levels of pro-inflammatory gene transcripts was confirmed by inhibiting the MEK-ERK1/2 signaling pathway, which led to the attenuated IL-6 and IL-1β expressions but not that of TNF-α. Moreover, as a key regulator of tau internalization, LRP1 (low-density lipoprotein receptor-related protein 1) levels were downregulated in response to monomeric tau added to C6 cells, while it was upregulated in HSPG-deficient cells, suggesting that the involvement of LRP1 in tau uptake depends on the presence of HSPGs on the cell surface. The subsequent LRP1 knockdown experiment we performed shows that LRP1 deficiency leads to an attenuated propensity for tau uptake and further elevated IL-6 gene expression. Collectively, our data suggest that tau has multiple extracellular binding partners that mediate its internalization through distinct mechanisms. Additionally, this study demonstrates the important role of both HSPGs and LRP1 in regulating cellular immune responses to tau protein monomers, providing a novel target for alleviating the neuroinflammatory environment before the formation of neurofibrillary tangles.
Collapse
Affiliation(s)
- Liqing Song
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Daniel E Oseid
- Tulane Brain Institute, Tulane University, New Orleans, LA, 70118, USA
| | - Evan A Wells
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Troy Coaston
- Tulane Brain Institute, Tulane University, New Orleans, LA, 70118, USA
| | - Anne S Robinson
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
- Tulane Brain Institute, Tulane University, New Orleans, LA, 70118, USA.
| |
Collapse
|
46
|
The neuronal retromer can regulate both neuronal and microglial phenotypes of Alzheimer's disease. Cell Rep 2022; 38:110262. [PMID: 35045281 PMCID: PMC8830374 DOI: 10.1016/j.celrep.2021.110262] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 09/14/2021] [Accepted: 12/22/2021] [Indexed: 02/03/2023] Open
Abstract
Disruption of retromer-dependent endosomal trafficking is considered pathogenic in late-onset Alzheimer's disease (AD). Here, to investigate this disruption in the intact brain, we turn to a genetic mouse model where the retromer core protein VPS35 is depleted in hippocampal neurons, and then we replete VPS35 using an optimized viral vector protocol. The VPS35 depletion-repletion studies strengthen the causal link between the neuronal retromer and AD-associated neuronal phenotypes, including the acceleration of amyloid precursor protein cleavage and the loss of synaptic glutamate receptors. Moreover, the studies show that the neuronal retromer can regulate a distinct, dystrophic, microglia morphology, phenotypic of hippocampal microglia in AD. Finally, the neuronal and, in part, the microglia responses to VPS35 depletion were found to occur independent of tau. Showing that the neuronal retromer can regulate AD-associated pathologies in two of AD's principal cell types strengthens the link, and clarifies the mechanism, between endosomal trafficking and late-onset sporadic AD.
Collapse
|
47
|
Limorenko G, Lashuel HA. Revisiting the grammar of Tau aggregation and pathology formation: how new insights from brain pathology are shaping how we study and target Tauopathies. Chem Soc Rev 2021; 51:513-565. [PMID: 34889934 DOI: 10.1039/d1cs00127b] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Converging evidence continues to point towards Tau aggregation and pathology formation as central events in the pathogenesis of Alzheimer's disease and other Tauopathies. Despite significant advances in understanding the morphological and structural properties of Tau fibrils, many fundamental questions remain about what causes Tau to aggregate in the first place. The exact roles of cofactors, Tau post-translational modifications, and Tau interactome in regulating Tau aggregation, pathology formation, and toxicity remain unknown. Recent studies have put the spotlight on the wide gap between the complexity of Tau structures, aggregation, and pathology formation in the brain and the simplicity of experimental approaches used for modeling these processes in research laboratories. Embracing and deconstructing this complexity is an essential first step to understanding the role of Tau in health and disease. To help deconstruct this complexity and understand its implication for the development of effective Tau targeting diagnostics and therapies, we firstly review how our understanding of Tau aggregation and pathology formation has evolved over the past few decades. Secondly, we present an analysis of new findings and insights from recent studies illustrating the biochemical, structural, and functional heterogeneity of Tau aggregates. Thirdly, we discuss the importance of adopting new experimental approaches that embrace the complexity of Tau aggregation and pathology as an important first step towards developing mechanism- and structure-based therapies that account for the pathological and clinical heterogeneity of Alzheimer's disease and Tauopathies. We believe that this is essential to develop effective diagnostics and therapies to treat these devastating diseases.
Collapse
Affiliation(s)
- Galina Limorenko
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, École Polytechnique Federal de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, École Polytechnique Federal de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
| |
Collapse
|
48
|
Desale SE, Chinnathambi S. α- Linolenic acid modulates phagocytosis and endosomal pathways of extracellular Tau in microglia. Cell Adh Migr 2021; 15:84-100. [PMID: 33724164 PMCID: PMC7971307 DOI: 10.1080/19336918.2021.1898727] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 12/19/2020] [Accepted: 02/19/2021] [Indexed: 12/17/2022] Open
Abstract
Microglia, the resident immune cells, were found to be activated to inflammatory phenotype in Alzheimer's disease (AD). The extracellular burden of amyloid-β plaques and Tau seed fabricate the activation of microglia. The seeding effect of extracellular Tau species is an emerging aspect to study about Tauopathies in AD. Tau seeds enhance the propagation of disease along with its contribution to microglia-mediated inflammation. The excessive neuroinflammation cumulatively hampers phagocytic function of microglia reducing the clearance of extracellular protein aggregates. Omega-3 fatty acids, especially docosahexaenoic acid and eicosapentaenoic acid, are recognized to induce anti-inflammatory phenotype of microglia. In addition to increased cytokine production, omega-3 fatty acids enhance phagocytic receptors expression in microglia. In this study, we have observed the phagocytosis of extracellular Tau in the presence of α-linolenic acid (ALA). The increased phagocytosis of extracellular Tau monomer and aggregates have been observed upon ALA exposure to microglia cells. After internalization, the degradation status of Tau has been studied with early and late endosomal markers Rab5 and Rab7. Further, the lysosome-mediated degradation of internalized Tau was studied with LAMP-2A, a lysosome marker. The enhanced migratory ability in the presence of ALA could be beneficial for microglia to access the target and clear it. The increased migration of microglia was found to induce the microtubule-organizing center repolarization. The data indicate that the dietary fatty acids ALA could significantly enhance phagocytosis and intracellular degradation of internalized Tau. Our results suggest that microglia could be influenced to reduce extracellular Tau seed with dietary fatty acids.
Collapse
Affiliation(s)
- Smita Eknath Desale
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical LaboratoryPune, India
- Academy of Scientific and Innovative Research (Acsir), Ghaziabad, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical LaboratoryPune, India
- Academy of Scientific and Innovative Research (Acsir), Ghaziabad, India
| |
Collapse
|
49
|
Rodriguez Camargo DC, Sileikis E, Chia S, Axell E, Bernfur K, Cataldi RL, Cohen SIA, Meisl G, Habchi J, Knowles TPJ, Vendruscolo M, Linse S. Proliferation of Tau 304-380 Fragment Aggregates through Autocatalytic Secondary Nucleation. ACS Chem Neurosci 2021; 12:4406-4415. [PMID: 34783519 PMCID: PMC8640994 DOI: 10.1021/acschemneuro.1c00454] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
![]()
The self-assembly
of the protein tau into neurofibrillary tangles
is one of the hallmarks of Alzheimer’s disease and related
tauopathies. Still, the molecular mechanism of tau aggregation is
largely unknown. This problem may be addressed by systematically obtaining
reproducible in vitro kinetics measurements under quiescent conditions
in the absence of triggering substances. Here, we implement this strategy
by developing protocols for obtaining an ultrapure tau fragment (residues
304–380 of tau441) and for performing spontaneous aggregation
assays with reproducible kinetics under quiescent conditions. We are
thus able to identify the mechanism of fibril formation of the tau
304–380 fragment at physiological pH using fluorescence spectroscopy
and mass spectrometry. We find that primary nucleation is slow, and
that secondary processes dominate the aggregation process once the
initial aggregates are formed. Moreover, our results further show
that secondary nucleation of monomers on fibril surfaces dominates
over fragmentation of fibrils. Using separate isotopes in monomers
and fibrils, through mass spectroscopy measurements, we verify the
isotope composition of the intermediate oligomeric species, which
reveals that these small aggregates are generated from monomer through
secondary nucleation. Our results provide a framework for understanding
the processes leading to tau aggregation in disease and for selecting
possible tau forms as targets in the development of therapeutic interventions
in Alzheimer’s disease.
Collapse
Affiliation(s)
- Diana C. Rodriguez Camargo
- Department of Biochemistry and Structural Biology, Chemical Centre, Lund University, SE-221 00 Lund, Sweden
- Wren Therapeutics Limited, Clarendon House, Clarendon Road, Cambridge CB2 8FH, United Kingdom
| | - Eimantas Sileikis
- Wren Therapeutics Limited, Clarendon House, Clarendon Road, Cambridge CB2 8FH, United Kingdom
| | - Sean Chia
- Wren Therapeutics Limited, Clarendon House, Clarendon Road, Cambridge CB2 8FH, United Kingdom
| | - Emil Axell
- Department of Biochemistry and Structural Biology, Chemical Centre, Lund University, SE-221 00 Lund, Sweden
| | - Katja Bernfur
- Department of Biochemistry and Structural Biology, Chemical Centre, Lund University, SE-221 00 Lund, Sweden
| | - Rodrigo L. Cataldi
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
| | - Samuel I. A. Cohen
- Wren Therapeutics Limited, Clarendon House, Clarendon Road, Cambridge CB2 8FH, United Kingdom
| | - Georg Meisl
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
| | - Johnny Habchi
- Wren Therapeutics Limited, Clarendon House, Clarendon Road, Cambridge CB2 8FH, United Kingdom
| | - Tuomas P. J. Knowles
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
| | - Sara Linse
- Department of Biochemistry and Structural Biology, Chemical Centre, Lund University, SE-221 00 Lund, Sweden
| |
Collapse
|
50
|
Vigneswaran J, Muthukumar SA, Shafras M, Pant G. An insight into Alzheimer’s disease and its on-setting novel genes. THE EGYPTIAN JOURNAL OF NEUROLOGY, PSYCHIATRY AND NEUROSURGERY 2021. [DOI: 10.1186/s41983-021-00420-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractAccording to the World Health Organisation, as of 2019, globally around 50 million people suffer from dementia, with approximately another 10 million getting added to the list every year, wherein Alzheimer’s disease (AD) stands responsible for almost a whopping 60–70% for the existing number of cases. Alzheimer’s disease is one of the progressive, cognitive-declining, age-dependent, neurodegenerative diseases which is distinguished by histopathological symptoms, such as formation of amyloid plaque, senile plaque, neurofibrillary tangles, etc. Majorly four vital transcripts are identified in the AD complications which include Amyloid precursor protein (APP), Apolipoprotein E (ApoE), and two multi-pass transmembrane domain proteins—Presenilin 1 and 2. In addition, the formation of the abnormal filaments such as amyloid beta (Aβ) and tau and their tangling with some necessary factors contributing to the formation of plaques, neuroinflammation, and apoptosis which in turn leads to the emergence of AD. Although multiple molecular mechanisms have been elucidated so far, they are still counted as hypotheses ending with neuronal death on the basal forebrain and hippocampal area which results in AD. This review article is aimed at addressing the overview of the molecular mechanisms surrounding AD and the functional forms of the genes associated with it.
Collapse
|