1
|
Marshall KE, Mengham K, Spink MC, Vania L, Pollard HJ, Darrow MC, Duke E, Harkiolaki M, Serpell LC. Correlative cryo-soft X-ray tomography and cryo-structured illumination microscopy reveal changes to lysosomes in amyloid-β-treated neurons. Structure 2024; 32:585-593.e3. [PMID: 38471506 DOI: 10.1016/j.str.2024.02.010] [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: 10/10/2023] [Revised: 12/20/2023] [Accepted: 02/15/2024] [Indexed: 03/14/2024]
Abstract
Protein misfolding is common to neurodegenerative diseases (NDs) including Alzheimer's disease (AD), which is partly characterized by the self-assembly and accumulation of amyloid-beta in the brain. Lysosomes are a critical component of the proteostasis network required to degrade and recycle material from outside and within the cell and impaired proteostatic mechanisms have been implicated in NDs. We have previously established that toxic amyloid-beta oligomers are endocytosed, accumulate in lysosomes, and disrupt the endo-lysosomal system in neurons. Here, we use pioneering correlative cryo-structured illumination microscopy and cryo-soft X-ray tomography imaging techniques to reconstruct 3D cellular architecture in the native state revealing reduced X-ray density in lysosomes and increased carbon dense vesicles in oligomer treated neurons compared with untreated cells. This work provides unprecedented visual information on the changes to neuronal lysosomes inflicted by amyloid beta oligomers using advanced methods in structural cell biology.
Collapse
Affiliation(s)
- Karen E Marshall
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, BN1 9QG Brighton, UK.
| | - Kurtis Mengham
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, BN1 9QG Brighton, UK
| | - Matthew C Spink
- Diamond Light Source, Diamond House, Harwell Science and Innovation Campus, Fermi Avenue, OX11 0DE Didcot, UK
| | - Lyra Vania
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, BN1 9QG Brighton, UK
| | - Hannah Jane Pollard
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, BN1 9QG Brighton, UK
| | - Michele C Darrow
- Diamond Light Source, Diamond House, Harwell Science and Innovation Campus, Fermi Avenue, OX11 0DE Didcot, UK
| | - Elizabeth Duke
- Diamond Light Source, Diamond House, Harwell Science and Innovation Campus, Fermi Avenue, OX11 0DE Didcot, UK
| | - Maria Harkiolaki
- Diamond Light Source, Diamond House, Harwell Science and Innovation Campus, Fermi Avenue, OX11 0DE Didcot, UK
| | - Louise C Serpell
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, BN1 9QG Brighton, UK.
| |
Collapse
|
2
|
Liang Z, Zhuang H, Cao X, Ma G, Shen L. Subcellular proteomics insights into Alzheimer's disease development. Proteomics Clin Appl 2024; 18:e2200112. [PMID: 37650321 DOI: 10.1002/prca.202200112] [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: 04/30/2023] [Revised: 07/27/2023] [Accepted: 08/12/2023] [Indexed: 09/01/2023]
Abstract
Alzheimer's disease (AD), one of the most common dementias, is a neurodegenerative disease characterized by cognitive impairment and decreased judgment function. The expected number of AD patient is increasing in the context of the world's advancing medical care and increasing human life expectancy. Since current molecular mechanism studies on AD pathogenesis are incomplete, there is no specific and effective therapeutic agent. Mass spectrometry (MS)-based unbiased proteomics studies provide an effective and comprehensive approach. Many advances have been made in the study of the mechanism, diagnostic markers, and drug targets of AD using proteomics. This paper focus on subcellular level studies, reviews studies using proteomics to study AD-associated mitochondrial dysfunction, synaptic, and myelin damage, the protein composition of amyloid plaques (APs) and neurofibrillary tangles (NFTs), changes in tissue extracellular vehicles (EVs) and exosome proteome, and the protein changes in ribosomes and lysosomes. The methods of sample separation and preparation and proteomic analysis as well as the main findings of these studies are involved. The results of these proteomics studies provide insights into the pathogenesis of AD and provide theoretical resource and direction for future research in AD, helping to identify new biomarkers and drugs targets for AD.
Collapse
Affiliation(s)
- Zhiyuan Liang
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, P. R. China
| | - Hongbin Zhuang
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, P. R. China
| | - Xueshan Cao
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, P. R. China
- College of Physics and Optoelectronics Engineering, Shenzhen University, Shenzhen, P. R. China
| | - Guanwei Ma
- School of Public Health, the key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guiyang, P. R. China
| | - Liming Shen
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, P. R. China
- Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, P. R. China
| |
Collapse
|
3
|
Kapadia A, Theil S, Opitz S, Villacampa N, Beckert H, Schoch S, Heneka MT, Kumar S, Walter J. Phosphorylation-state dependent intraneuronal sorting of Aβ differentially impairs autophagy and the endo-lysosomal system. Autophagy 2024; 20:166-187. [PMID: 37642583 PMCID: PMC10761119 DOI: 10.1080/15548627.2023.2252300] [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: 01/09/2023] [Revised: 08/17/2023] [Accepted: 08/21/2023] [Indexed: 08/31/2023] Open
Abstract
ABBREVIATIONS AD: Alzheimer disease; APP: amyloid beta precursor protein; ATG: autophagy related; Aβ: amyloid-β; CTSD: cathepsin D; DAPI: 4',6-diamidino-2-phenylindole; EEA1: early endosome antigen 1; FA: formic acid; GFP: green fluorescent protein; LAMP2: lysosomal-associated membrane protein 2; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MAP2: microtubule-associated protein 2; nmAβ: non-modified amyloid-β; npAβ: non-phosphorylated amyloid-β; pAβ: phosphorylated amyloid-β; p-Ser26Aβ: amyloid-β phosphorylated at serine residue 26; p-Ser8Aβ: amyloid-β phosphorylated at serine residue 8; RAB: RAB, member RAS oncogene family; RFP: red fluorescent protein; SQSTM1/p62: sequestome 1; YFP: yellow fluorescent protein.
Collapse
Affiliation(s)
- Akshay Kapadia
- Molecular Cell Biology, Department of Neurology, University Hospital Bonn, Bonn, Germany
| | - Sandra Theil
- Molecular Cell Biology, Department of Neurology, University Hospital Bonn, Bonn, Germany
| | - Sabine Opitz
- Neuroinflammation Unit, German Center for Neurodegenerative Diseases e. V. (DZNE), Bonn, Germany
- Section for Translational Epilepsy Research, Department of Neuropathology, University Hospital Bonn, Bonn, Germany
| | - Nàdia Villacampa
- Neuroinflammation Unit, German Center for Neurodegenerative Diseases e. V. (DZNE), Bonn, Germany
| | - Hannes Beckert
- Microscopy core facility, University Hospital Bonn, Bonn, Germany
| | - Susanne Schoch
- Section for Translational Epilepsy Research, Department of Neuropathology, University Hospital Bonn, Bonn, Germany
| | - Michael. T. Heneka
- Neuroinflammation Unit, German Center for Neurodegenerative Diseases e. V. (DZNE), Bonn, Germany
- Department of Neurodegenerative Disease and Geriatric Psychiatry, University Hospital Bonn, Bonn, Germany
| | - Sathish Kumar
- Molecular Cell Biology, Department of Neurology, University Hospital Bonn, Bonn, Germany
| | - Jochen Walter
- Molecular Cell Biology, Department of Neurology, University Hospital Bonn, Bonn, Germany
| |
Collapse
|
4
|
Feng J, She Y, Li C, Shen L. Metal ion mediated aggregation of Alzheimer's disease peptides and proteins in solutions and at surfaces. Adv Colloid Interface Sci 2023; 320:103009. [PMID: 37776735 DOI: 10.1016/j.cis.2023.103009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/29/2023] [Accepted: 09/24/2023] [Indexed: 10/02/2023]
Abstract
Although the pathogenesis of Alzheimer's disease (AD) is still unclear, abnormally high concentrations of metal ions, like copper, iron and zinc, were found in senile plaques of AD brain, which inspires extensive studies on the fundamental molecular interactions of metal ions with the pathogenic hallmarks, amyloid-β (Aβ) peptides and tau proteins, respectively forming senile plaques and neurofibrillary tangles (NFTs) in AD brains. Early works concern the concentration effect of the metal ions on Aβ and tau aggregation. Yet, it is obvious that the surrounding environment of the metal ions must also be considered, not just the metal ions as free accessible forms in the solution phase. The most important surrounding environment in vivo is a very large surface area from cell membranes and other macromolecular surfaces. These bio-interfaces make the kinetic pathways of metal ion mediated Aβ and tau aggregation radically different from those in the solution phase. To better understand the role of metal ions in AD peptide and protein aggregation, we summarize and discuss the recent achievements in the research of metal ion mediated Aβ and tau aggregation, particularly the corresponding mechanism differences between the solution phase and the surface environment. The metal ion chelation therapy for AD is also discussed from the point of the surface pool of metal ions.
Collapse
Affiliation(s)
- Jiahao Feng
- Key Laboratory for Neurodegenerative Diseases Nanomedicine of Hubei Province, School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Yifei She
- Key Laboratory for Neurodegenerative Diseases Nanomedicine of Hubei Province, School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Chongjia Li
- Key Laboratory for Neurodegenerative Diseases Nanomedicine of Hubei Province, School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Lei Shen
- Key Laboratory for Neurodegenerative Diseases Nanomedicine of Hubei Province, School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China.
| |
Collapse
|
5
|
Yoon M, Phan V, Podvin S, Mosier C, O’Donoghue AJ, Hook V. Distinct Cleavage Properties of Cathepsin B Compared to Cysteine Cathepsins Enable the Design and Validation of a Specific Substrate for Cathepsin B over a Broad pH Range. Biochemistry 2023; 62:2289-2300. [PMID: 37459182 PMCID: PMC10399199 DOI: 10.1021/acs.biochem.3c00139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/11/2023] [Indexed: 08/02/2023]
Abstract
The biological and pathological functions of cathepsin B occur in acidic lysosomes and at the neutral pH of cytosol, nuclei, and extracellular locations. Importantly, cathepsin B displays different substrate cleavage properties at acidic pH compared to neutral pH conditions. It is, therefore, desirable to develop specific substrates for cathepsin B that measure its activity over broad pH ranges. Current substrates used to monitor cathepsin B activity consist of Z-Phe-Arg-AMC and Z-Arg-Arg-AMC, but they lack specificity since they are cleaved by other cysteine cathepsins. Furthermore, Z-Arg-Arg-AMC monitors cathepsin B activity at neutral pH and displays minimal activity at acidic pH. Therefore, the purpose of this study was to design and validate specific fluorogenic peptide substrates that can monitor cathepsin B activity over a broad pH range from acidic to neutral pH conditions. In-depth cleavage properties of cathepsin B were compared to those of the cysteine cathepsins K, L, S, V, and X via multiplex substrate profiling by mass spectrometry at pH 4.6 and pH 7.2. Analysis of the cleavage preferences predicted the tripeptide Z-Nle-Lys-Arg-AMC as a preferred substrate for cathepsin B. Significantly, Z-Nle-Lys-Arg-AMC displayed the advantageous properties of measuring high cathepsin B specific activity over acidic to neutral pHs and was specifically cleaved by cathepsin B over the other cysteine cathepsins. Z-Nle-Lys-Arg-AMC specifically monitored cathepsin B activity in neuronal and glial cells which were consistent with relative abundances of cathepsin B protein. These findings validate Z-Nle-Lys-Arg-AMC as a novel substrate that specifically monitors cathepsin B activity over a broad pH range.
Collapse
Affiliation(s)
- Michael
C. Yoon
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
- Biomedical
Sciences Graduate Program, University of
California, La Jolla, San Diego, California 92093, United States
| | - Von Phan
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
- Biomedical
Sciences Graduate Program, University of
California, La Jolla, San Diego, California 92093, United States
| | - Sonia Podvin
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
| | - Charles Mosier
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
| | - Anthony J. O’Donoghue
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
| | - Vivian Hook
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
- Biomedical
Sciences Graduate Program, University of
California, La Jolla, San Diego, California 92093, United States
- Department
of Neurosciences and Department of Pharmacology, School of Medicine, University of California, La Jolla, San Diego, California 92093, United States
| |
Collapse
|
6
|
Chou CC, Vest R, Prado MA, Wilson-Grady J, Paulo JA, Shibuya Y, Moran-Losada P, Lee TT, Luo J, Gygi SP, Kelly JW, Finley D, Wernig M, Wyss-Coray T, Frydman J. Proteostasis and lysosomal quality control deficits in Alzheimer's disease neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.27.534444. [PMID: 37034684 PMCID: PMC10081252 DOI: 10.1101/2023.03.27.534444] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The role of proteostasis and organelle homeostasis dysfunction in human aging and Alzheimer's disease (AD) remains unclear. Analyzing proteome-wide changes in human donor fibroblasts and their corresponding transdifferentiated neurons (tNeurons), we find aging and AD synergistically impair multiple proteostasis pathways, most notably lysosomal quality control (LQC). In particular, we show that ESCRT-mediated lysosomal repair defects are associated with both sporadic and PSEN1 familial AD. Aging- and AD-linked defects are detected in fibroblasts but highly exacerbated in tNeurons, leading to enhanced neuronal vulnerability, unrepaired lysosomal damage, inflammatory factor secretion and cytotoxicity. Surprisingly, tNeurons from aged and AD donors spontaneously develop amyloid-β inclusions co-localizing with LQC markers, LAMP1/2-positive lysosomes and proteostasis factors; we observe similar inclusions in brain tissue from AD patients and APP-transgenic mice. Importantly, compounds enhancing lysosomal function broadly ameliorate these AD-associated pathologies. Our findings establish cell-autonomous LQC dysfunction in neurons as a central vulnerability in aging and AD pathogenesis.
Collapse
|
7
|
Penke B, Szűcs M, Bogár F. New Pathways Identify Novel Drug Targets for the Prevention and Treatment of Alzheimer’s Disease. Int J Mol Sci 2023; 24:ijms24065383. [PMID: 36982456 PMCID: PMC10049476 DOI: 10.3390/ijms24065383] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/06/2023] [Accepted: 03/09/2023] [Indexed: 03/18/2023] Open
Abstract
Alzheimer’s disease (AD) is an incurable, progressive neurodegenerative disorder. AD is a complex and multifactorial disease that is responsible for 60–80% of dementia cases. Aging, genetic factors, and epigenetic changes are the main risk factors for AD. Two aggregation-prone proteins play a decisive role in AD pathogenesis: β-amyloid (Aβ) and hyperphosphorylated tau (pTau). Both of them form deposits and diffusible toxic aggregates in the brain. These proteins are the biomarkers of AD. Different hypotheses have tried to explain AD pathogenesis and served as platforms for AD drug research. Experiments demonstrated that both Aβ and pTau might start neurodegenerative processes and are necessary for cognitive decline. The two pathologies act in synergy. Inhibition of the formation of toxic Aβ and pTau aggregates has been an old drug target. Recently, successful Aβ clearance by monoclonal antibodies has raised new hopes for AD treatments if the disease is detected at early stages. More recently, novel targets, e.g., improvements in amyloid clearance from the brain, application of small heat shock proteins (Hsps), modulation of chronic neuroinflammation by different receptor ligands, modulation of microglial phagocytosis, and increase in myelination have been revealed in AD research.
Collapse
Affiliation(s)
- Botond Penke
- Department of Medical Chemistry, University of Szeged, Dóm Square 8, H-6720 Szeged, Hungary
- Correspondence:
| | - Mária Szűcs
- Department of Medical Chemistry, University of Szeged, Dóm Square 8, H-6720 Szeged, Hungary
| | - Ferenc Bogár
- ELKH-SZTE Biomimetic Systems Research Group, Eötvös Loránd Research Network (ELKH), Dóm Square 8, H-6720 Szeged, Hungary
| |
Collapse
|
8
|
Hoyer MJ, Swarup S, Harper JW. Mechanisms Controlling Selective Elimination of Damaged Lysosomes. CURRENT OPINION IN PHYSIOLOGY 2022; 29:100590. [PMID: 36713230 PMCID: PMC9878802 DOI: 10.1016/j.cophys.2022.100590] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Lysosomes are subjected to physiological and patho-physiological insults over the course of their life cycle and are accordingly repaired or recycled. Lysophagy, the selective degradation of lysosomes via autophagy, occurs upon unrepairable lysosomal membrane rupture; galectins bind to glycosylated macromolecules in the lysosome lumen, orchestrating a series of cellular responses to promote autophagic recycling of damaged lysosomes and transcriptional upregulation of lysosomal genes. Damaged lysosomes are ubiquitylated, resulting in the recruitment of ubiquitin-binding autophagy receptors, which promote assembly of an autophagosome around damaged lysosomes for delivery to healthy lysosomes for degradation. Here, we review the current state of our understanding of mechanisms used to mark and eliminate damaged lysosomes, and discuss the complexities of galectin function and ubiquitin-chain linkage types. Finally, we discuss the limitations of available data and challenges with the goal of understanding the mechanistic basis of key steps in lysophagic flux.
Collapse
Affiliation(s)
- Melissa J. Hoyer
- Department of Cell Biology, Harvard Medical School, 240 Longwood Ave, Boston MA 02115, USA,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Sharan Swarup
- Department of Cell Biology, Harvard Medical School, 240 Longwood Ave, Boston MA 02115, USA
| | - J. Wade Harper
- Department of Cell Biology, Harvard Medical School, 240 Longwood Ave, Boston MA 02115, USA,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| |
Collapse
|
9
|
Wu Q, Karthivashan G, Nakhaei-Nejad M, Anand BG, Giuliani F, Kar S. Native PLGA nanoparticles regulate APP metabolism and protect neurons against β-amyloid toxicity: Potential significance in Alzheimer's disease pathology. Int J Biol Macromol 2022; 219:1180-1196. [PMID: 36030976 DOI: 10.1016/j.ijbiomac.2022.08.148] [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: 05/21/2022] [Revised: 08/18/2022] [Accepted: 08/22/2022] [Indexed: 11/05/2022]
Abstract
Biodegradable poly(lactic-co-glycolic acid)(PLGA) nanoparticles have been used extensively in delivering drugs to target tissues due to their excellent biocompatibility. Evidence suggests that PLGA-conjugated drugs/agents can attenuate pathology in cellular/animal models of Alzheimer's disease (AD), which is initiated by increased level/aggregation of amyloid β (Aβ) peptide generated from amyloid precursor protein (APP). The beneficial effects were attributed to conjugated-drugs rather than to PLGA nanoparticles. Interestingly, we recently reported that PLGA without any drug/agent (native PLGA) can suppress Aβ aggregation/toxicity. However, very little is known about the internalization, subcellular localization or effects of PLGA in neurons. In this study, using primary mouse cortical neurons, we first showed that native PLGA is internalized by an energy-mediated clathrin-dependent/-independent pathway and is localized in endosomal-lysosomal-autophagic vesicles. By attenuating internalization, PLGA can protect neurons against Aβ-mediated toxicity. Additionally, PLGA treatment altered expression profiles of certain AD-associated genes and decreased the levels of APP, its cleaved products α-/β-CTFs and Aβ peptides in mouse as well as iPSC-derived neurons from control and AD patients. Collectively, these results suggest that native PLGA not only protects neurons against Aβ-induced toxicity but also influences the expression of AD-related genes/proteins - highlighting PLGA's implication in normal and AD-related pathology.
Collapse
Affiliation(s)
- Qi Wu
- Departments of Medicine (Neurology), Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
| | - Govindarajan Karthivashan
- Departments of Medicine (Neurology), Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
| | - Maryam Nakhaei-Nejad
- Departments of Medicine (Neurology), Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
| | - Bibin G Anand
- Departments of Medicine (Neurology), Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
| | - Fabrizio Giuliani
- Departments of Medicine (Neurology), Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
| | - Satyabrata Kar
- Departments of Medicine (Neurology), Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
| |
Collapse
|
10
|
McKendell AK, Houser MCQ, Mitchell SPC, Wolfe MS, Berezovska O, Maesako M. In-Depth Characterization of Endo-Lysosomal Aβ in Intact Neurons. BIOSENSORS 2022; 12:bios12080663. [PMID: 36005059 PMCID: PMC9406119 DOI: 10.3390/bios12080663] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/17/2022] [Accepted: 08/18/2022] [Indexed: 12/21/2022]
Abstract
Amyloid-beta (Aβ) peptides are produced within neurons. Some peptides are released into the brain parenchyma, while others are retained inside the neurons. However, the detection of intracellular Aβ remains a challenge since antibodies against Aβ capture Aβ and its precursor proteins (i.e., APP and C99). To overcome this drawback, we recently developed 1) the C99 720-670 biosensor for recording γ-secretase activity and 2) a unique multiplexed immunostaining platform that enables the selective detection of intracellular Aβ with subcellular resolution. Using these new assays, we showed that C99 is predominantly processed by γ-secretase in late endosomes and lysosomes, and intracellular Aβ is enriched in the same subcellular loci in intact neurons. However, the detailed properties of Aβ in the acidic compartments remain unclear. Here, we report using fluorescent lifetime imaging microscopy (FLIM) that intracellular Aβ includes both long Aβ intermediates bound to γ-secretase and short peptides dissociated from the protease complex. Surprisingly, our results also suggest that the dissociated Aβ is bound to the glycoproteins on the inner membrane of lysosomes. Furthermore, we show striking cell-to-cell heterogeneity in intracellular Aβ levels in primary neurons and APP transgenic mouse brains. These findings provide a basis for the further investigation of the role(s) of intracellular Aβ and its relevance to Alzheimer’s disease (AD).
Collapse
Affiliation(s)
- Alec K. McKendell
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, 114, 16th street, Charlestown, MA 02129, USA
| | - Mei C. Q. Houser
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, 114, 16th street, Charlestown, MA 02129, USA
| | - Shane P. C. Mitchell
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, 114, 16th street, Charlestown, MA 02129, USA
| | - Michael S. Wolfe
- Department of Medicinal Chemistry, University of Kansas, 1567 Irving Hill Rd, Lawrence, Kansas City, KS 66045, USA
| | - Oksana Berezovska
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, 114, 16th street, Charlestown, MA 02129, USA
| | - Masato Maesako
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, 114, 16th street, Charlestown, MA 02129, USA
- Correspondence: ; Tel.: +1-617-724-2579
| |
Collapse
|
11
|
Macroautophagy and Mitophagy in Neurodegenerative Disorders: Focus on Therapeutic Interventions. Biomedicines 2021; 9:biomedicines9111625. [PMID: 34829854 PMCID: PMC8615936 DOI: 10.3390/biomedicines9111625] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/01/2021] [Accepted: 11/03/2021] [Indexed: 02/06/2023] Open
Abstract
Macroautophagy, a quality control mechanism, is an evolutionarily conserved pathway of lysosomal degradation of protein aggregates, pathogens, and damaged organelles. As part of its vital homeostatic role, macroautophagy deregulation is associated with various human disorders, including neurodegenerative diseases. There are several lines of evidence that associate protein misfolding and mitochondrial dysfunction in the etiology of Alzheimer’s, Parkinson’s, and Huntington’s diseases. Macroautophagy has been implicated in the degradation of different protein aggregates such as Aβ, tau, alpha-synuclein (α-syn), and mutant huntingtin (mHtt) and in the clearance of dysfunctional mitochondria. Taking these into consideration, targeting autophagy might represent an effective therapeutic strategy to eliminate protein aggregates and to improve mitochondrial function in these disorders. The present review describes our current understanding on the role of macroautophagy in neurodegenerative disorders and focuses on possible strategies for its therapeutic modulation.
Collapse
|
12
|
Raha S, Ghosh A, Dutta D, Patel DR, Pahan K. Activation of PPARα enhances astroglial uptake and degradation of β-amyloid. Sci Signal 2021; 14:eabg4747. [PMID: 34699252 DOI: 10.1126/scisignal.abg4747] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
[Figure: see text].
Collapse
Affiliation(s)
- Sumita Raha
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
| | - Arunava Ghosh
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
| | - Debashis Dutta
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
| | - Dhruv R Patel
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
| | - Kalipada Pahan
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA.,Division of Research and Development, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA
| |
Collapse
|
13
|
Yoon MC, Solania A, Jiang Z, Christy MP, Podvin S, Mosier C, Lietz CB, Ito G, Gerwick WH, Wolan DW, Hook G, O’Donoghue AJ, Hook V. Selective Neutral pH Inhibitor of Cathepsin B Designed Based on Cleavage Preferences at Cytosolic and Lysosomal pH Conditions. ACS Chem Biol 2021; 16:1628-1643. [PMID: 34416110 DOI: 10.1021/acschembio.1c00138] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Cathepsin B is a cysteine protease that normally functions within acidic lysosomes for protein degradation, but in numerous human diseases, cathepsin B translocates to the cytosol having neutral pH where the enzyme activates inflammation and cell death. Cathepsin B is active at both the neutral pH 7.2 of the cytosol and the acidic pH 4.6 within lysosomes. We evaluated the hypothesis that cathepsin B may possess pH-dependent cleavage preferences that can be utilized for design of a selective neutral pH inhibitor by (1) analysis of differential cathepsin B cleavage profiles at neutral pH compared to acidic pH using multiplex substrate profiling by mass spectrometry (MSP-MS), (2) design of pH-selective peptide-7-amino-4-methylcoumarin (AMC) substrates, and (3) design and validation of Z-Arg-Lys-acyloxymethyl ketone (AOMK) as a selective neutral pH inhibitor. Cathepsin B displayed preferences for cleaving peptides with Arg in the P2 position at pH 7.2 and Glu in the P2 position at pH 4.6, represented by its primary dipeptidyl carboxypeptidase and modest endopeptidase activity. These properties led to design of the substrate Z-Arg-Lys-AMC having neutral pH selectivity, and its modification with the AOMK warhead to result in the inhibitor Z-Arg-Lys-AOMK. This irreversible inhibitor displays nanomolar potency with 100-fold selectivity for inhibition of cathepsin B at pH 7.2 compared to pH 4.6, shows specificity for cathepsin B over other cysteine cathepsins, and is cell permeable and inhibits intracellular cathepsin B. These findings demonstrate that cathepsin B possesses pH-dependent cleavage properties that can lead to development of a potent, neutral pH inhibitor of this enzyme.
Collapse
Affiliation(s)
- Michael C. Yoon
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093, United States
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, California 92093, United States
| | - Angelo Solania
- Departments of Molecular Medicine and Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Zhenze Jiang
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093, United States
| | - Mitchell P. Christy
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093, United States
| | - Sonia Podvin
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093, United States
| | - Charles Mosier
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093, United States
| | - Christopher B. Lietz
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093, United States
| | - Gen Ito
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093, United States
| | - William H. Gerwick
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093, United States
| | - Dennis W. Wolan
- Departments of Molecular Medicine and Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Gregory Hook
- American Life Sciences Pharmaceuticals, Inc., La Jolla, California 92037, United States
| | - Anthony J. O’Donoghue
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093, United States
| | - Vivian Hook
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093, United States
- Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, California 92037, United States
| |
Collapse
|
14
|
Mohamed Asik R, Suganthy N, Aarifa MA, Kumar A, Szigeti K, Mathe D, Gulyás B, Archunan G, Padmanabhan P. Alzheimer's Disease: A Molecular View of β-Amyloid Induced Morbific Events. Biomedicines 2021; 9:biomedicines9091126. [PMID: 34572312 PMCID: PMC8468668 DOI: 10.3390/biomedicines9091126] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/22/2021] [Accepted: 08/27/2021] [Indexed: 12/26/2022] Open
Abstract
Amyloid-β (Aβ) is a dynamic peptide of Alzheimer’s disease (AD) which accelerates the disease progression. At the cell membrane and cell compartments, the amyloid precursor protein (APP) undergoes amyloidogenic cleavage by β- and γ-secretases and engenders the Aβ. In addition, externally produced Aβ gets inside the cells by receptors mediated internalization. An elevated amount of Aβ yields spontaneous aggregation which causes organelles impairment. Aβ stimulates the hyperphosphorylation of tau protein via acceleration by several kinases. Aβ travels to the mitochondria and interacts with its functional complexes, which impairs the mitochondrial function leading to the activation of apoptotic signaling cascade. Aβ disrupts the Ca2+ and protein homeostasis of the endoplasmic reticulum (ER) and Golgi complex (GC) that promotes the organelle stress and inhibits its stress recovery machinery such as unfolded protein response (UPR) and ER-associated degradation (ERAD). At lysosome, Aβ precedes autophagy dysfunction upon interacting with autophagy molecules. Interestingly, Aβ act as a transcription regulator as well as inhibits telomerase activity. Both Aβ and p-tau interaction with neuronal and glial receptors elevate the inflammatory molecules and persuade inflammation. Here, we have expounded the Aβ mediated events in the cells and its cosmopolitan role on neurodegeneration, and the current clinical status of anti-amyloid therapy.
Collapse
Affiliation(s)
- Rajmohamed Mohamed Asik
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore; (R.M.A.); (B.G.)
- Cognitive Neuroimaging Centre, 59 Nanyang Drive, Nanyang Technological University, Singapore 636921, Singapore
- Department of Animal Science, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India;
| | - Natarajan Suganthy
- Department of Nanoscience and Technology, Alagappa University, Karaikudi 630003, Tamil Nadu, India;
| | - Mohamed Asik Aarifa
- Department of Animal Science, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India;
| | - Arvind Kumar
- Centre for Cellular and Molecular Biology, Hyderabad 500007, Telangana, India;
| | - Krisztián Szigeti
- Department of Biophysics and Radiation Biology, Semmelweis University, 1094 Budapest, Hungary; (K.S.); (D.M.)
- CROmed Translational Research Centers, 1094 Budapest, Hungary
| | - Domokos Mathe
- Department of Biophysics and Radiation Biology, Semmelweis University, 1094 Budapest, Hungary; (K.S.); (D.M.)
- CROmed Translational Research Centers, 1094 Budapest, Hungary
- In Vivo Imaging Advanced Core Facility, Hungarian Center of Excellence for Molecular Medicine (HCEMM), 1094 Budapest, Hungary
| | - Balázs Gulyás
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore; (R.M.A.); (B.G.)
- Cognitive Neuroimaging Centre, 59 Nanyang Drive, Nanyang Technological University, Singapore 636921, Singapore
- Department of Clinical Neuroscience, Karolinska Institute, 17176 Stockholm, Sweden
| | - Govindaraju Archunan
- Department of Animal Science, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India;
- Marudupandiyar College, Thanjavur 613403, Tamil Nadu, India
- Correspondence: (G.A.); (P.P.)
| | - Parasuraman Padmanabhan
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore; (R.M.A.); (B.G.)
- Cognitive Neuroimaging Centre, 59 Nanyang Drive, Nanyang Technological University, Singapore 636921, Singapore
- Correspondence: (G.A.); (P.P.)
| |
Collapse
|
15
|
Divakara MB, Ashwini R, Santosh MS, Priyanka M, Ravikumar CR, Viswanatha R, Murthy HCA. Early-stage culprit in protein misfolding diseases investigated using electrochemical parameters: New insights over peptide-membrane interactions. Biomed Pharmacother 2021; 142:111964. [PMID: 34329823 DOI: 10.1016/j.biopha.2021.111964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 11/16/2022] Open
Abstract
The dysfunctioning of β-cells caused by the unspecific misfolding of the human islet amyloid polypeptide (hIAPP) at the membrane results in type 2 diabetes mellitus. Here, we report for the first time, the early-stage interaction of hIAPP oligomers on the DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) lipid membrane using electrochemical parameters. Electrochemical techniques are better than other techniques to detect hIAPP at significantly lower concentrations. The surface level interactions between the peptide (hIAPP) and lipid membrane (DMPC) were investigated using atomic force microscopy (AFM), confocal microscopy (CM) and electrochemical techniques such as Tafel polarization, cyclic voltammetry (CV), differential pulse voltammetry (DPV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). Inserting IAPP into the fluid domains results in breaking the lipid-to-lipid interaction, leading to restriction of membrane mobility. The SLateral values of the liposome and IAPP co-solubilized liposome indicates the cooperative insertion of IAPP. Further, a new method of immobilizing a membrane to the gold surface has been employed, resulting in an electrical contact with the buffer, preventing the direct utilization of a steady-state voltage across the bilayer. The electrochemical studies revealed that the charge transfer resistance decreased for 3-mercaptopropanoic acid modified gold (MPA-Au) electrode coated with the liposome and after the addition of IAPP, followed by an increase in the capacitance. The present study has opened up new dimensions to the understanding of peptide-membrane interactions and shows different experimental approaches for the future researchers in this domain.
Collapse
Affiliation(s)
- M B Divakara
- Centre for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology (Affiliated to Visvesvaraya Technological University (VTU), Belgaum), Thataguni, Off Kanakapura Road, Bengaluru 560082, Karnataka, India
| | - R Ashwini
- Centre for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology (Affiliated to Visvesvaraya Technological University (VTU), Belgaum), Thataguni, Off Kanakapura Road, Bengaluru 560082, Karnataka, India
| | - M S Santosh
- Centre for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology (Affiliated to Visvesvaraya Technological University (VTU), Belgaum), Thataguni, Off Kanakapura Road, Bengaluru 560082, Karnataka, India.
| | - M Priyanka
- East Point college of Medical Sciences and Research Centre (affiliated to RGUHS), Jnana Prabha, Virgonagar Post, Bidrahalli, Bengaluru 560049, Karnataka, India
| | - C R Ravikumar
- Research Centre, Department of Science, East West Institute of Technology, Bengaluru 560091, India
| | - R Viswanatha
- Centre for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology (Affiliated to Visvesvaraya Technological University (VTU), Belgaum), Thataguni, Off Kanakapura Road, Bengaluru 560082, Karnataka, India
| | - H C Ananda Murthy
- Department of Applied Chemistry, School of Applied Natural Science, Adama Science and Technology University, P O Box 1888, Adama, Ethiopia.
| |
Collapse
|
16
|
Morris C, Kent TW, Shen F, Wojcikiewicz EP, Du D. Effects of the Hydrophilic N-Terminal Region on Aβ-Mediated Membrane Disruption. J Phys Chem B 2021; 125:7671-7678. [PMID: 34252282 DOI: 10.1021/acs.jpcb.1c03413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Amyloidogenesis of amyloid-β (Aβ) peptides is intimately related to pathological neurodegeneration in Alzheimer's disease. Here, we investigated the membrane damage activity of Aβ40 and its derivatives that contain mutation at the N-terminal charged residues using a membrane leakage assay. A model 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) phospholipid vesicle encapsulating the fluorescent dye carboxyfluorescein was used in the study. Our results show that the mutations of the N-terminal charged residues of Aβ40 significantly affect the peptide-induced membrane leakage. The results suggest that favorable electrostatic interactions of the N-terminal charged residues and the phosphatidylcholine membrane surface are crucial in Aβ-mediated membrane permeation. The flexible and charge-rich N-terminal region may play a critical role in directing Aβ self-association on the membrane surface and in anchoring and stabilizing the peptide aggregates inserted in the phospholipid membrane, which are closely related with membrane disruption activity of Aβ. The results provide new mechanistic insight into the Aβ-mediated membrane damage process, which may be critical for understanding the mechanism of Aβ neurotoxicity in Alzheimer's disease.
Collapse
Affiliation(s)
- Clifford Morris
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Thomas W Kent
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Fengyun Shen
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Ewa P Wojcikiewicz
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Deguo Du
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| |
Collapse
|
17
|
Uddin MS, Al Mamun A, Rahman MA, Behl T, Perveen A, Hafeez A, Bin-Jumah MN, Abdel-Daim MM, Ashraf GM. Emerging Proof of Protein Misfolding and Interactions in Multifactorial Alzheimer's Disease. Curr Top Med Chem 2021; 20:2380-2390. [PMID: 32479244 DOI: 10.2174/1568026620666200601161703] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/21/2020] [Accepted: 04/27/2020] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Alzheimer's disease (AD) is a devastating neurodegenerative disorder, characterized by the extracellular accumulations of amyloid beta (Aβ) as senile plaques and intracellular aggregations of tau in the form of neurofibrillary tangles (NFTs) in specific brain regions. In this review, we focus on the interaction of Aβ and tau with cytosolic proteins and several cell organelles as well as associated neurotoxicity in AD. SUMMARY Misfolded proteins present in cells accompanied by correctly folded, intermediately folded, as well as unfolded species. Misfolded proteins can be degraded or refolded properly with the aid of chaperone proteins, which are playing a pivotal role in protein folding, trafficking as well as intermediate stabilization in healthy cells. The continuous aggregation of misfolded proteins in the absence of their proper clearance could result in amyloid disease including AD. The neuropathological changes of AD brain include the atypical cellular accumulation of misfolded proteins as well as the loss of neurons and synapses in the cerebral cortex and certain subcortical regions. The mechanism of neurodegeneration in AD that leads to severe neuronal cell death and memory dysfunctions is not completely understood until now. CONCLUSION Examining the impact, as well as the consequences of protein misfolding, could help to uncover the molecular etiologies behind the complicated AD pathogenesis.
Collapse
Affiliation(s)
- Md Sahab Uddin
- Department of Pharmacy, Southeast University, Dhaka, Bangladesh,Pharmakon Neuroscience Research Network, Dhaka, Bangladesh
| | - Abdullah Al Mamun
- Department of Pharmacy, Southeast University, Dhaka, Bangladesh,Pharmakon Neuroscience Research Network, Dhaka, Bangladesh
| | - Md Ataur Rahman
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Republic of Korea
| | - Tapan Behl
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Asma Perveen
- Glocal School of Life Sciences, Glocal University, Saharanpur, India
| | - Abdul Hafeez
- Glocal School of Pharmacy, Glocal University, Saharanpur, India
| | - May N Bin-Jumah
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, Riyadh 11474, Saudi Arabia
| | - Mohamed M Abdel-Daim
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia,Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Ghulam Md Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia,Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| |
Collapse
|
18
|
Anand BG, Wu Q, Karthivashan G, Shejale KP, Amidian S, Wille H, Kar S. Mimosine functionalized gold nanoparticles (Mimo-AuNPs) suppress β-amyloid aggregation and neuronal toxicity. Bioact Mater 2021; 6:4491-4505. [PMID: 34027236 PMCID: PMC8131740 DOI: 10.1016/j.bioactmat.2021.04.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/18/2021] [Accepted: 04/19/2021] [Indexed: 12/27/2022] Open
Abstract
Evidence suggests that increased level/aggregation of beta-amyloid (Aβ) peptides initiate neurodegeneration and subsequent development of Alzheimer's disease (AD). At present, there is no effective treatment for AD. In this study, we reported the effects of gold nanoparticles surface-functionalized with a plant-based amino acid mimosine (Mimo-AuNPs), which is found to cross the blood-brain barrier, on the Aβ fibrillization process and toxicity. Thioflavin T kinetic assays, fluorescence imaging and electron microscopy data showed that Mimo-AuNPs were able to suppress the spontaneous and seed-induced Aβ1-42 aggregation. Spectroscopic studies, molecular docking and biochemical analyses further revealed that Mimo-AuNPs stabilize Aβ1-42 to remain in its monomeric state by interacting with the hydrophobic domain of Aβ1-42 (i.e., Lys16 to Ala21) there by preventing a conformational shift towards the β-sheet structure. Additionally, Mimo-AuNPs were found to trigger the disassembly of matured Aβ1-42 fibers and increased neuronal viability by reducing phosphorylation of tau protein and the production of oxyradicals. Collectively, these results reveal that the surface-functionalization of gold nanoparticles with mimosine can attenuate Aβ fibrillization and neuronal toxicity. Thus, we propose Mimo-AuNPs may be used as a potential treatment strategy towards AD-related pathologies. Mimosine functionalized with gold nanoparticles (Mimo-AuNPs) can cross blood-brain barrier. Mimo-AuNPs inhibit aggregation of Aβ peptides by interacting with its hydrophobic domain. Mimo-AuNPs can trigger disassembly of pre-aggregated Aβ fibers. Mimo-AuNPs can protect neurons against Aβ toxicity by attenuating intracellular signaling.
Collapse
Affiliation(s)
- Bibin G Anand
- Departments of Medicine and University of Alberta, Edmonton, Alberta, T6G 2M8, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, T6G 2M8, Canada
| | - Qi Wu
- Departments of Medicine and University of Alberta, Edmonton, Alberta, T6G 2M8, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, T6G 2M8, Canada
| | - Govindarajan Karthivashan
- Departments of Medicine and University of Alberta, Edmonton, Alberta, T6G 2M8, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, T6G 2M8, Canada
| | - Kiran P Shejale
- Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Powai, India
| | - Sara Amidian
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, T6G 2M8, Canada.,Departments of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2M8, Canada
| | - Holger Wille
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, T6G 2M8, Canada.,Departments of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2M8, Canada
| | - Satyabrata Kar
- Departments of Medicine and University of Alberta, Edmonton, Alberta, T6G 2M8, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, T6G 2M8, Canada
| |
Collapse
|
19
|
Cai S, Liu C, He S, Zhao L, Zeng X. Mitochondria-targeted fluorescent probe for imaging endogenous hydrogen sulfide in cellular antioxidant stress. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:5061-5067. [PMID: 33052994 DOI: 10.1039/d0ay01200a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Hydrogen sulfide (H2S) is believed to play an important role in maintaining cellular redox homeostasis and avoiding oxidative damage caused by abnormally raised ROS levels. Highly selective and sensitive fluorescent probes for the detection and imaging of endogenous H2S in living cells over other biological thiols are desirable. Herein, we developed a mitochondria-targeted fluorescent probe L, a thioxanthene-benzo[e]indolium derivative, for the discrimination of H2S from other chemically similar biothiols. Based on the nucleophilic addition of H2S and the charged electron-deficient C[double bond, length as m-dash]N double bond within the benzo[e]indolium moiety, the generation of L-HS with a shortened π-conjugated system led to significant spectral changes in the visible region. Importantly, the probe L with mitochondria-targeting ability has been successfully used for imaging the endogenous H2S biosynthesized from Cys and GSH and in cellular antioxidant stress.
Collapse
Affiliation(s)
- Songtao Cai
- Tianjin Key Laboratory for Photoelectric Materials and Devices, Key Laboratory of Display Materials & Photoelectric Devices, Ministry of Education, School of Materials Science & Engineering, Tianjin University of Technology, Tianjin 300384, China.
| | | | | | | | | |
Collapse
|
20
|
Gu Y, Bai L, Zhang Y, Zhang H, Xing D, Tian L, Zhou Y, Hao J, Liu Y. Liposome as drug delivery system enhance anticancer activity of iridium (III) complex. J Liposome Res 2020; 31:342-355. [PMID: 32892672 DOI: 10.1080/08982104.2020.1818779] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Herein an Ir(III) complex [Ir(Hppy)2(HMNPIP)](PF6) (Ir1, Hppy = 2-phenylpyridine, HMNPIP = 2-(1H-imidazo[4,5-f][1, 10]phenanthroline-3-yl)-6-methoxy-4-nitrophenol) was prepared and characterized. Due to the low anticancer activity of Ir1 when administered free drug, we prepared a liposome Ir1Lipo encapsulated form of Ir1 to improve the antitumor effect, furthermore, we explored the antitumor mechanism of both forms in vitro experiments on HepG2 cells. We investigated the inhibitory efficiency of Ir1 and Ir1Lipo on cell viability and proliferation using MTT (MTT = 3-(4,5-dimethylthiazole)-2,5-diphenltetraazolium bromide) and colony-forming assay. Intracellular accumulation of reactive oxygen species (ROS) was examined using a fluorescence microscope (High Content Screening System, ImageXpress Micro XLS System, Molecular Devices LLC, Sunnyvale, CA), programmed cell death cells stained with acridine orange/ethidium bromide (AO/EB) using flow cytometry detection and western blot have been performed. An in vivo study where HepG2 cells were transplanted into nude nice as xenografts. Tumour volume and body weight were monitored during the 10 days of administration. After encapsulation in liposomes Ir1Lipo displayed high potency against a variety of tumour cells in vitro, especially against HepG2 (IC50 = 4.6 ± 0.5 μM). Mechanism studies indicated that Ir1Lipo initiated apoptosis by generating intracellular ROS that regulate lysosomal-mitochondrial dysfunction, followed by microtubule disruption that subsequently leads to a G0/G1 phase of cell cycle arrest. Additionally, Ir1Lipo significantly curbed tumour growth in nude mice. The tumour inhibitory rate was 51.2% (5.6 mg/kg). Therefore, liposome as a drug delivery system greatly enhances anticancer activity of Ir1 by a factor of relatively minor side effects.
Collapse
Affiliation(s)
- Yiying Gu
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, PR China
| | - Lan Bai
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, PR China
| | - Yuanyuan Zhang
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, PR China
| | - Huiwen Zhang
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, PR China
| | - Degang Xing
- School of Biosciences and Biopharmaceutics, Guangdong Pharmaceutical University, Guangzhou, PR China
| | - Li Tian
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, PR China
| | - Yi Zhou
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, PR China
| | - Jing Hao
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, PR China
| | - Yunjun Liu
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, PR China
| |
Collapse
|
21
|
Wang Y, Wu Q, Anand BG, Karthivashan G, Phukan G, Yang J, Thinakaran G, Westaway D, Kar S. Significance of cytosolic cathepsin D in Alzheimer's disease pathology: Protective cellular effects of PLGA nanoparticles against β-amyloid-toxicity. Neuropathol Appl Neurobiol 2020; 46:686-706. [PMID: 32716575 DOI: 10.1111/nan.12647] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 06/25/2020] [Accepted: 07/12/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND Evidence suggests that amyloid β (Aβ) peptides play an important role in the degeneration of neurons during the development of Alzheimer's disease (AD), the prevalent cause of dementia affecting the elderly. The endosomal-lysosomal system, which acts as a major site for Aβ metabolism, has been shown to exhibit abnormalities in vulnerable neurons of the AD brain, reflected by enhanced levels/expression of lysosomal enzymes including cathepsin D (CatD). At present, the implication of CatD in selective neuronal vulnerability in AD pathology remains unclear. METHODS We evaluated the role of CatD in the degeneration of neurons in Aβ-treated cultures, transgenic AD mouse model (that is 5xFAD) and post mortem AD brain samples. RESULTS Our results showed that Aβ1-42 -induced toxicity in cortical cultured neurons is associated with impaired lysosomal integrity, enhanced levels of carbonylated proteins and tau phosphorylation. The cellular and cytosolic levels/activity of CatD are also elevated in cultured neurons following exposure to Aβ peptide. Additionally, we observed that CatD cellular and subcellular levels/activity are increased in the affected cortex, but not in the unaffected cerebellum, of 5xFAD mice and post mortem AD brains. Interestingly, treatment of cultured neurons with nanoparticles PLGA, which targets lysosomal system, attenuated Aβ toxicity by reducing the levels of carbonylated proteins, tau phosphorylation and the level/distribution/activity of CatD. CONCLUSION Our study reveals that increased cytosolic level/activity of CatD play an important role in determining neuronal vulnerability in AD. Additionally, native PLGA can protect neurons against Aβ toxicity by restoring lysosomal membrane integrity, thus signifying its implication in attenuating AD.
Collapse
Affiliation(s)
- Y Wang
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Q Wu
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - B G Anand
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - G Karthivashan
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - G Phukan
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - J Yang
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - G Thinakaran
- Department of Molecular Medicine, and Byrd Alzheimer's Institute, University of South Florida, Tampa, FL, 33613, USA
| | - D Westaway
- Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - S Kar
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| |
Collapse
|
22
|
Bécot A, Volgers C, van Niel G. Transmissible Endosomal Intoxication: A Balance between Exosomes and Lysosomes at the Basis of Intercellular Amyloid Propagation. Biomedicines 2020; 8:biomedicines8080272. [PMID: 32759666 PMCID: PMC7459801 DOI: 10.3390/biomedicines8080272] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 07/28/2020] [Accepted: 07/31/2020] [Indexed: 12/16/2022] Open
Abstract
In Alzheimer′s disease (AD), endolysosomal dysfunctions are amongst the earliest cellular features to appear. Each organelle of the endolysosomal system, from the multivesicular body (MVB) to the lysosome, contributes to the homeostasis of amyloid precursor protein (APP) cleavage products including β-amyloid (Aβ) peptides. Hence, this review will attempt to disentangle how changes in the endolysosomal system cumulate to the generation of toxic amyloid species and hamper their degradation. We highlight that the formation of MVBs and the generation of amyloid species are closely linked and describe how the molecular machineries acting at MVBs determine the generation and sorting of APP cleavage products towards their degradation or release in association with exosomes. In particular, we will focus on AD-related distortions of the endolysomal system that divert it from its degradative function to favour the release of exosomes and associated amyloid species. We propose here that such an imbalance transposed at the brain scale poses a novel concept of transmissible endosomal intoxication (TEI). This TEI would initiate a self-perpetuating transmission of endosomal dysfunction between cells that would support the propagation of amyloid species in neurodegenerative diseases.
Collapse
|
23
|
Annexin A5 prevents amyloid-β-induced toxicity in choroid plexus: implication for Alzheimer's disease. Sci Rep 2020; 10:9391. [PMID: 32523019 PMCID: PMC7286910 DOI: 10.1038/s41598-020-66177-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/09/2020] [Indexed: 12/11/2022] Open
Abstract
In Alzheimer’s disease (AD) amyloid-β (Aβ) deposits may cause impairments in choroid plexus, a specialised brain structure which forms the blood–cerebrospinal fluid (CSF) barrier. We previously carried out a mass proteomic-based study in choroid plexus from AD patients and we found several differentially regulated proteins compared with healthy subjects. One of these proteins, annexin A5, was previously demonstrated implicated in blocking Aβ-induced cytotoxicity in neuronal cell cultures. Here, we investigated the effects of annexin A5 on Aβ toxicity in choroid plexus. We used choroid plexus tissue samples and CSF from mild cognitive impairment (MCI) and AD patients to analyse Aβ accumulation, cell death and annexin A5 levels compared with control subjects. Choroid plexus cell cultures from rats were used to analyse annexin A5 effects on Aβ-induced cytotoxicity. AD choroid plexus exhibited progressive reduction of annexin A5 levels along with progressive increased Aβ accumulation and cell death as disease stage was higher. On the other hand, annexin A5 levels in CSF from patients were found progressively increased as the disease stage increased in severity. In choroid plexus primary cultures, Aβ administration reduced endogenous annexin A5 levels in a time-course dependent manner and simultaneously increased annexin A5 levels in extracellular medium. Annexin A5 addition to choroid plexus cell cultures restored the Aβ-induced impairments on autophagy flux and apoptosis in a calcium-dependent manner. We propose that annexin A5 would exert a protective role in choroid plexus and this protection is lost as Aβ accumulates with the disease progression. Then, brain protection against further toxic insults would be jeopardised.
Collapse
|
24
|
Hook V, Yoon M, Mosier C, Ito G, Podvin S, Head BP, Rissman R, O'Donoghue AJ, Hook G. Cathepsin B in neurodegeneration of Alzheimer's disease, traumatic brain injury, and related brain disorders. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140428. [PMID: 32305689 DOI: 10.1016/j.bbapap.2020.140428] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/31/2020] [Accepted: 04/08/2020] [Indexed: 12/21/2022]
Abstract
Investigations of Alzheimer's disease (AD), traumatic brain injury (TBI), and related brain disorders have provided extensive evidence for involvement of cathepsin B, a lysosomal cysteine protease, in mediating the behavioral deficits and neuropathology of these neurodegenerative diseases. This review integrates findings of cathepsin B regulation in clinical biomarker studies, animal model genetic and inhibitor evaluations, structural studies, and lysosomal cell biological mechanisms in AD, TBI, and related brain disorders. The results together indicate the role of cathepsin B in the behavioral deficits and neuropathology of these disorders. Lysosomal leakage occurs in AD and TBI, and related neurodegeneration, which leads to the hypothesis that cathepsin B is redistributed from the lysosome to the cytosol where it initiates cell death and inflammation processes associated with neurodegeneration. These results together implicate cathepsin B as a major contributor to these neuropathological changes and behavioral deficits. These findings support the investigation of cathepsin B as a potential drug target for therapeutic discovery and treatment of AD, TBI, and TBI-related brain disorders.
Collapse
Affiliation(s)
- Vivian Hook
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, United States of America; Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, United States of America.
| | - Michael Yoon
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, United States of America
| | - Charles Mosier
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Gen Ito
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Sonia Podvin
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Brian P Head
- VA San Diego Healthcare System, La Jolla, CA, United States of America; Department of Anesthesia, University of California San Diego, La Jolla, CA, United States of America
| | - Robert Rissman
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, United States of America; VA San Diego Healthcare System, La Jolla, CA, United States of America
| | - Anthony J O'Donoghue
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Gregory Hook
- American Life Sciences Pharmaceuticals, Inc., La Jolla, CA, United States of America
| |
Collapse
|
25
|
Kandlur A, Satyamoorthy K, Gangadharan G. Oxidative Stress in Cognitive and Epigenetic Aging: A Retrospective Glance. Front Mol Neurosci 2020; 13:41. [PMID: 32256315 PMCID: PMC7093495 DOI: 10.3389/fnmol.2020.00041] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 03/02/2020] [Indexed: 12/17/2022] Open
Abstract
Brain aging is the critical and common factor among several neurodegenerative disorders and dementia. Cellular, biochemical and molecular studies have shown intimate links between oxidative stress and cognitive dysfunction during aging and age-associated neuronal diseases. Brain aging is accompanied by oxidative damage of nuclear as well as mitochondrial DNA, and diminished repair. Recent studies have reported epigenetic alterations during aging of the brain which involves reactive oxygen species (ROS) that regulates various systems through distinct mechanisms. However, there are studies which depict differing roles of reactive oxidant species as a major factor during aging. In this review, we describe the evidence to show how oxidative stress is intricately linked to age-associated cognitive decline. The review will primarily focus on implications of age-associated oxidative damage on learning and memory, and the cellular events, with special emphasis on associated epigenetic machinery. A comprehensive understanding of these mechanisms may provide a perspective on the development of potential therapeutic targets within the oxidative system.
Collapse
Affiliation(s)
| | | | - Gireesh Gangadharan
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, India
| |
Collapse
|
26
|
β-Amyloid Peptide: the Cell Compartment Multi-faceted Interaction in Alzheimer's Disease. Neurotox Res 2019; 37:250-263. [PMID: 31811589 DOI: 10.1007/s12640-019-00116-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 08/29/2019] [Accepted: 09/16/2019] [Indexed: 12/17/2022]
Abstract
Alzheimer's disease (AD) is the most widespread form of dementia, characterized by memory loss and reduction of cognitive functions that strongly interfere with normal daily life. Numerous evidences show that aggregates of the amyloid beta peptide, formed by 39 to 42 amino acid residues (Aβ39-43), from soluble small oligomers to large fibrils are characteristic markers of this pathology. However, AD is a complex disease and its neurodegenerative molecular mechanism is not yet fully understood. Growing evidence suggests a link between Aβ polymorphic nature, oligomers and fibrils, and specific mechanisms of neurodegeneration. The Aβ variable nature and its multiplicity of interactions with different proteins and organelles reflect the complexity of this pathology. In this review, we analyze the effects of the interaction between Aβ peptide and different cellular compartments in relation to the different kinds and sizes of amyloid aggregates. In particular, Aβ interaction with different cell structures such as the plasma membrane, mitochondria, lysosomes, nucleus, and endoplasmic reticulum is discussed. Further, we analyze the Aβ peptide ability to modify the structure and function of the target organelle, inducing alteration of its physiological role thus contributing to the pathological event. Dysfunction of cellular components terminating with the activation of the cellular death mechanism and subsequent neurodegeneration is also taken into consideration.
Collapse
|
27
|
Zhang C, Li S, Yu A, Wang Y. Nano CaCO3 “Lysosomal Bombs” Enhance Chemotherapy Drug Efficacy via Rebalancing Tumor Intracellular pH. ACS Biomater Sci Eng 2019; 5:3398-3408. [DOI: 10.1021/acsbiomaterials.9b00436] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
|
28
|
Maity BK, Das AK, Dey S, Moorthi UK, Kaur A, Dey A, Surendran D, Pandit R, Kallianpur M, Chandra B, Chandrakesan M, Arumugam S, Maiti S. Ordered and Disordered Segments of Amyloid-β Drive Sequential Steps of the Toxic Pathway. ACS Chem Neurosci 2019; 10:2498-2509. [PMID: 30763064 DOI: 10.1021/acschemneuro.9b00015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
While the roles of intrinsically disordered protein domains in driving interprotein interactions are increasingly well-appreciated, the mechanism of toxicity of disease-causing disordered proteins remains poorly understood. A prime example is Alzheimer's disease (AD) associated amyloid beta (Aβ). Aβ oligomers are highly toxic partially structured peptide assemblies with a distinct ordered region (residues ∼10-40) and a shorter disordered region (residues ∼1-9). Here, we investigate the role of this disordered domain and its relation to the ordered domain in the manifestation of toxicity through a set of Aβ fragments and stereoisomers designed for this purpose. We measure their effects on lipid membranes and cultured neurons, probing their toxicity, intracellular distributions, and specific molecular interactions using the techniques of confocal imaging, lattice light sheet imaging, fluorescence lifetime imaging, and fluorescence correlation spectroscopy. Remarkably, we find that neither part-Aβ10-40 or Aβ1-9, is toxic by itself. The ordered part (Aβ10-40) is the major determinant of how Aβ attaches to lipid bilayers, enters neuronal cells, and localizes primarily in the late endosomal compartments. However, once Aβ enters the cell, it is the disordered part (only when it is connected to the rest of the peptide) that has a strong and stereospecific interaction with an unknown cellular component, as demonstrated by distinct changes in the fluorescence lifetime of a fluorophore attached to the N-terminal. This interaction appears to commit Aβ to the toxic pathway. Our findings correlate well with Aβ sites of familial AD mutations, a significant fraction of which cluster in the disordered region. We conclude that, while the ordered region dictates attachment and cellular entry, the key to toxicity lies in the ordered part presenting the disordered part for a specific cellular interaction.
Collapse
Affiliation(s)
- Barun Kumar Maity
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Anand Kant Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Simli Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | | | | | - Arpan Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Dayana Surendran
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Rucha Pandit
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Mamata Kallianpur
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Bappaditya Chandra
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Muralidharan Chandrakesan
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | | | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| |
Collapse
|
29
|
Deng L, Pushpitha K, Joseph C, Gupta V, Rajput R, Chitranshi N, Dheer Y, Amirkhani A, Kamath K, Pascovici D, Wu JX, Salekdeh GH, Haynes PA, Graham SL, Gupta VK, Mirzaei M. Amyloid β Induces Early Changes in the Ribosomal Machinery, Cytoskeletal Organization and Oxidative Phosphorylation in Retinal Photoreceptor Cells. Front Mol Neurosci 2019; 12:24. [PMID: 30853886 PMCID: PMC6395395 DOI: 10.3389/fnmol.2019.00024] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 01/21/2019] [Indexed: 01/20/2023] Open
Abstract
Amyloid β (Aβ) accumulation and its aggregation is characteristic molecular feature of the development of Alzheimer's disease (AD). More recently, Aβ has been suggested to be associated with retinal pathology associated with AD, glaucoma and drusen deposits in age related macular degeneration (AMD). In this study, we investigated the proteins and biochemical networks that are affected by Aβ in the 661 W photoreceptor cells in culture. Time and dose dependent effects of Aβ on the photoreceptor cells were determined utilizing tandem mass tag (TMT) labeling-based quantitative mass-spectrometric approach. Bioinformatic analysis of the data revealed concentration and time dependent effects of the Aβ peptide stimulation on various key biochemical pathways that might be involved in mediating the toxicity effects of the peptide. We identified increased Tau phosphorylation, GSK3β dysregulation and reduced cell viability in cells treated with Aβ in a dose and time dependent manner. This study has delineated for the first-time molecular networks in photoreceptor cells that are impacted early upon Aβ treatment and contrasted the findings with a longer-term treatment effect. Proteins associated with ribosomal machinery homeostasis, mitochondrial function and cytoskeletal organization were affected in the initial stages of Aβ exposure, which may provide key insights into AD effects on the photoreceptors and specific molecular changes induced by Aβ peptide.
Collapse
Affiliation(s)
- Liting Deng
- Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
| | - Kanishka Pushpitha
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Chitra Joseph
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Veer Gupta
- School of Medicine, Deakin University, Waurn Ponds, VIC, Australia
| | - Rashi Rajput
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Nitin Chitranshi
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Yogita Dheer
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Ardeshir Amirkhani
- Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
- Australian Proteome Analysis Facility (APAF), Macquarie University, Sydney, NSW, Australia
| | - Karthik Kamath
- Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
- Australian Proteome Analysis Facility (APAF), Macquarie University, Sydney, NSW, Australia
| | - Dana Pascovici
- Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
- Australian Proteome Analysis Facility (APAF), Macquarie University, Sydney, NSW, Australia
| | - Jemma X. Wu
- Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
- Australian Proteome Analysis Facility (APAF), Macquarie University, Sydney, NSW, Australia
| | - Ghasem Hosseini Salekdeh
- Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
- Cell Science Research Center, Department of Molecular Systems Biology, Royan Institute for Stem Cell Biology and Technology, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran
| | - Paul A. Haynes
- Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
| | - Stuart L. Graham
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Vivek K. Gupta
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Mehdi Mirzaei
- Department of Molecular Sciences, Faculty of Science and Engineering, Macquarie University, Sydney, NSW, Australia
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
- Australian Proteome Analysis Facility (APAF), Macquarie University, Sydney, NSW, Australia
| |
Collapse
|
30
|
Morris G, Berk M, Maes M, Puri BK. Could Alzheimer's Disease Originate in the Periphery and If So How So? Mol Neurobiol 2019; 56:406-434. [PMID: 29705945 PMCID: PMC6372984 DOI: 10.1007/s12035-018-1092-y] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 04/17/2018] [Indexed: 12/11/2022]
Abstract
The classical amyloid cascade model for Alzheimer's disease (AD) has been challenged by several findings. Here, an alternative molecular neurobiological model is proposed. It is shown that the presence of the APOE ε4 allele, altered miRNA expression and epigenetic dysregulation in the promoter region and exon 1 of TREM2, as well as ANK1 hypermethylation and altered levels of histone post-translational methylation leading to increased transcription of TNFA, could variously explain increased levels of peripheral and central inflammation found in AD. In particular, as a result of increased activity of triggering receptor expressed on myeloid cells 2 (TREM-2), the presence of the apolipoprotein E4 (ApoE4) isoform, and changes in ANK1 expression, with subsequent changes in miR-486 leading to altered levels of protein kinase B (Akt), mechanistic (previously mammalian) target of rapamycin (mTOR) and signal transducer and activator of transcription 3 (STAT3), all of which play major roles in microglial activation, proliferation and survival, there is activation of microglia, leading to the subsequent (further) production of cytokines, chemokines, nitric oxide, prostaglandins, reactive oxygen species, inducible nitric oxide synthase and cyclooxygenase-2, and other mediators of inflammation and neurotoxicity. These changes are associated with the development of amyloid and tau pathology, mitochondrial dysfunction (including impaired activity of the electron transport chain, depleted basal mitochondrial potential and oxidative damage to key tricarboxylic acid enzymes), synaptic dysfunction, altered glycogen synthase kinase-3 (GSK-3) activity, mTOR activation, impairment of autophagy, compromised ubiquitin-proteasome system, iron dyshomeostasis, changes in APP translation, amyloid plaque formation, tau hyperphosphorylation and neurofibrillary tangle formation.
Collapse
Affiliation(s)
- Gerwyn Morris
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, P.O. Box 291, Geelong, Victoria, Australia
| | - Michael Berk
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, P.O. Box 291, Geelong, Victoria, Australia
- Department of Psychiatry, Level 1 North, Main Block, Royal Melbourne Hospital, University of Melbourne, Parkville, Victoria, Australia
- Florey Institute for Neuroscience and Mental Health, Kenneth Myer Building, University of Melbourne, 30 Royal Parade, Parkville, Victoria, Australia
- Orygen, The National Centre of Excellence in Youth Mental Health, 35 Poplar Rd, Parkville, Victoria, Australia
| | - Michael Maes
- IMPACT Strategic Research Centre, School of Medicine, Barwon Health, Deakin University, P.O. Box 291, Geelong, Victoria, Australia
- Department of Psychiatry, Chulalongkorn University, Bangkok, Thailand
| | - Basant K Puri
- Department of Medicine, Hammersmith Hospital, Imperial College London, London, UK.
| |
Collapse
|
31
|
Synaptic activity protects against AD and FTD-like pathology via autophagic-lysosomal degradation. Mol Psychiatry 2018; 23:1530-1540. [PMID: 28696431 PMCID: PMC5641448 DOI: 10.1038/mp.2017.142] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 04/10/2017] [Accepted: 05/09/2017] [Indexed: 12/27/2022]
Abstract
Changes in synaptic excitability and reduced brain metabolism are among the earliest detectable alterations associated with the development of Alzheimer's disease (AD). Stimulation of synaptic activity has been shown to be protective in models of AD beta-amyloidosis. Remarkably, deep brain stimulation (DBS) provides beneficial effects in AD patients, and represents an important therapeutic approach against AD and other forms of dementia. While several studies have explored the effect of synaptic activation on beta-amyloid, little is known about Tau protein. In this study, we investigated the effect of synaptic stimulation on Tau pathology and synapses in in vivo and in vitro models of AD and frontotemporal dementia (FTD). We found that chronic DBS or chemically induced synaptic stimulation reduced accumulation of pathological forms of Tau and protected synapses, while chronic inhibition of synaptic activity worsened Tau pathology and caused detrimental effects on pre- and post-synaptic markers, suggesting that synapses are affected. Interestingly, degradation via the proteasomal system was not involved in the reduction of pathological Tau during stimulation. In contrast, chronic synaptic activation promoted clearance of Tau oligomers by autophagosomes and lysosomes. Chronic inhibition of synaptic activity resulted in opposite outcomes, with build-up of Tau oligomers in enlarged auto-lysosomes. Our data indicate that synaptic activity counteracts the negative effects of Tau in AD and FTD by acting on autophagy, providing a rationale for therapeutic use of DBS and synaptic stimulation in tauopathies.
Collapse
|
32
|
Zhang M, Zhai Q, Wan L, Chen L, Peng Y, Deng C, Xiang J, Yan J. Electrochemical Impedance Spectroscopy for Real-Time Detection of Lipid Membrane Damage Based on a Porous Self-Assembly Monolayer Support. Anal Chem 2018; 90:7422-7427. [DOI: 10.1021/acs.analchem.8b00884] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Meng Zhang
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China
| | - Qingyu Zhai
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China
| | - Liping Wan
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China
| | - Li Chen
- State Key Laboratory of Physical Chemistry of the Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Yu Peng
- State Key Laboratory of Physical Chemistry of the Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Chunyan Deng
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China
| | - Juan Xiang
- College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, P. R. China
| | - Jiawei Yan
- State Key Laboratory of Physical Chemistry of the Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| |
Collapse
|
33
|
Penke B, Bogár F, Crul T, Sántha M, Tóth ME, Vígh L. Heat Shock Proteins and Autophagy Pathways in Neuroprotection: from Molecular Bases to Pharmacological Interventions. Int J Mol Sci 2018; 19:E325. [PMID: 29361800 PMCID: PMC5796267 DOI: 10.3390/ijms19010325] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 01/15/2018] [Accepted: 01/18/2018] [Indexed: 02/07/2023] Open
Abstract
Neurodegenerative diseases (NDDs) such as Alzheimer's disease, Parkinson's disease and Huntington's disease (HD), amyotrophic lateral sclerosis, and prion diseases are all characterized by the accumulation of protein aggregates (amyloids) into inclusions and/or plaques. The ubiquitous presence of amyloids in NDDs suggests the involvement of disturbed protein homeostasis (proteostasis) in the underlying pathomechanisms. This review summarizes specific mechanisms that maintain proteostasis, including molecular chaperons, the ubiquitin-proteasome system (UPS), endoplasmic reticulum associated degradation (ERAD), and different autophagic pathways (chaperon mediated-, micro-, and macro-autophagy). The role of heat shock proteins (Hsps) in cellular quality control and degradation of pathogenic proteins is reviewed. Finally, putative therapeutic strategies for efficient removal of cytotoxic proteins from neurons and design of new therapeutic targets against the progression of NDDs are discussed.
Collapse
Affiliation(s)
- Botond Penke
- Department of Medical Chemistry, University of Szeged, H-6720 Szeged, Dóm Square 8, Hungary.
| | - Ferenc Bogár
- Department of Medical Chemistry, University of Szeged, H-6720 Szeged, Dóm Square 8, Hungary.
- MTA-SZTE Biomimetic Systems Research Group, University of Szeged, H-6720 Szeged, Dóm Square 8, Hungary.
| | - Tim Crul
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, H-6726 Szeged, Temesvári krt. 62, Hungary.
| | - Miklós Sántha
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, H-6726 Szeged, Temesvári krt. 62, Hungary.
| | - Melinda E Tóth
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, H-6726 Szeged, Temesvári krt. 62, Hungary.
| | - László Vígh
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, H-6726 Szeged, Temesvári krt. 62, Hungary.
| |
Collapse
|
34
|
Ntsapi C, Lumkwana D, Swart C, du Toit A, Loos B. New Insights Into Autophagy Dysfunction Related to Amyloid Beta Toxicity and Neuropathology in Alzheimer's Disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 336:321-361. [DOI: 10.1016/bs.ircmb.2017.07.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
35
|
Veloria JR, Chen L, Li L, Breen GAM, Lee J, Goux WJ. Novel cell-penetrating-amyloid peptide conjugates preferentially kill cancer cells. MEDCHEMCOMM 2018; 9:121-130. [PMID: 30108906 PMCID: PMC6071918 DOI: 10.1039/c7md00321h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 09/09/2017] [Indexed: 01/13/2023]
Abstract
The goal of this study was to develop a peptide which could use the toxic effects of amyloid, a substance which is the hallmark of over 25 known human diseases, to selectively kill cancer cells. Here we demonstrate that two separate amyloid-forming hexapeptides, one from the microtubule associated protein Tau involved in formation of paired helical filaments of Alzheimer's disease, and the other an amyloid forming sequence from apolipoprotein A1, when conjugated to a cell penetrating peptide (CPP) sequence, form toxic oligomers which are stable for up to 14 h and able to enter cells by a combination of endocytosis and transduction. The amyloid peptide conjugates showed selective cytotoxicity to breast cancer, neuroblastoma and cervical cancer cells in culture compared to normal cells. Fluorescence imaging experiments showed the CPP-amyloid peptide oligomers formed intracellular fibrous amyloid, visible in the endosomes/lysosomes, cytosol and nucleus with thioflavin S (ThS) staining. Further experiments with rhodamine-conjugated Dextran, propidium iodide (PI), and acridine orange (AO) suggested the mechanism of cell death was the permeability of the lysosomal membrane brought about by the formation of amyloid pores. Cytotoxicity could be abrogated by inhibitors of lysosomal hydrolases, consistent with a model where lysosomal hydrolases leak into the cytosol and induce cytotoxicity in subsequent downstream steps. Taken together, our data suggest that CPP-amyloid peptide conjugates show potential as a new class of anti-cancer peptides (ACPs).
Collapse
Affiliation(s)
- John R Veloria
- Department of Biological Sciences , The University of Texas at Dallas , 800 W. Campbell Rd , Richardson , TX 75080 , USA
| | - Luxi Chen
- Department of Chemistry and Biochemistry , The University of Texas at Dallas , 800 W. Campbell Rd , Richardson , TX 75080 , USA .
| | - Lin Li
- Department of Biological Sciences , The University of Texas at Dallas , 800 W. Campbell Rd , Richardson , TX 75080 , USA
| | - Gail A M Breen
- Department of Biological Sciences , The University of Texas at Dallas , 800 W. Campbell Rd , Richardson , TX 75080 , USA
| | - Jiyong Lee
- Department of Chemistry and Biochemistry , The University of Texas at Dallas , 800 W. Campbell Rd , Richardson , TX 75080 , USA .
| | - Warren J Goux
- Department of Chemistry and Biochemistry , The University of Texas at Dallas , 800 W. Campbell Rd , Richardson , TX 75080 , USA .
| |
Collapse
|
36
|
Colacurcio DJ, Pensalfini A, Jiang Y, Nixon RA. Dysfunction of autophagy and endosomal-lysosomal pathways: Roles in pathogenesis of Down syndrome and Alzheimer's Disease. Free Radic Biol Med 2018; 114:40-51. [PMID: 28988799 PMCID: PMC5748263 DOI: 10.1016/j.freeradbiomed.2017.10.001] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 10/03/2017] [Accepted: 10/04/2017] [Indexed: 12/12/2022]
Abstract
Individuals with Down syndrome (DS) have an increased risk of early-onset Alzheimer's Disease (AD), largely owing to a triplication of the APP gene, located on chromosome 21. In DS and AD, defects in endocytosis and lysosomal function appear at the earliest stages of disease development and progress to widespread failure of intraneuronal waste clearance, neuritic dystrophy and neuronal cell death. The same genetic factors that cause or increase AD risk are also direct causes of endosomal-lysosomal dysfunction, underscoring the essential partnership between this dysfunction and APP metabolites in AD pathogenesis. The appearance of APP-dependent endosome anomalies in DS beginning in infancy and evolving into the full range of AD-related endosomal-lysosomal deficits provides a unique opportunity to characterize the earliest pathobiology of AD preceding the classical neuropathological hallmarks. Facilitating this characterization is the authentic recapitulation of this endosomal pathobiology in peripheral cells from people with DS and in trisomy mouse models. Here, we review current research on endocytic-lysosomal dysfunction in DS and AD, the emerging importance of APP/βCTF in initiating this dysfunction, and the potential roles of additional trisomy 21 genes in accelerating endosomal-lysosomal impairment in DS. Collectively, these studies underscore the growing value of investigating DS to probe the biological origins of AD as well as to understand and ameliorate the developmental disability of DS.
Collapse
Affiliation(s)
- Daniel J Colacurcio
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY 10016, USA
| | - Anna Pensalfini
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY 10016, USA
| | - Ying Jiang
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY 10016, USA
| | - Ralph A Nixon
- Center for Dementia Research, Nathan S. Kline Institute, Orangeburg, NY 10962, USA; Department of Psychiatry, New York University Langone Medical Center, New York, NY 10016, USA; Department of Cell Biology, New York University Langone Medical Center, New York, NY 10016, USA.
| |
Collapse
|
37
|
Veloria JR, Li L, Breen GAM, Goux WJ. Novel Cell Model for Tauopathy Induced by a Cell-Permeable Tau-Related Peptide. ACS Chem Neurosci 2017; 8:2734-2745. [PMID: 28837764 DOI: 10.1021/acschemneuro.7b00275] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In the present study, a cell penetrating peptide (CPP)-amyloid conjugate was prepared (T-peptide), where the amyloid-forming sequence was homologous to a nucleating sequence from human Tau protein (306VQIVYK311). Kinetic and biophysical studies showed the peptide formed long-lived oligomers which were taken up by endocytosis and localized in perinuclear vesicles and in the cytoplasm of murine hippocampal neuroblastoma cells and human HeLa cells. Thioflavin S (ThS) staining of amyloid colocalized with pathological phosphorylated Tau, suggesting that the peptide was able to seed endogenous wild-type Tau. Subsequent experiments showed that aggregates present in the lysosomes mediated lysosome membrane permeability (LMP). We observed a decrease in total Tau, irrespective of phosphorylation state, consistent with Tau fragmentation by lysosomal proteases. We found cytotoxicity of T-peptide could be abrogated by inhibitors of lysosomal hydrolases and caspases, consistent with a model where Tau fragments processed by the lysosome leak into the cytoplasm and induce toxicity in subsequent downstream steps. It is our hope that the T-peptide system may prove amenable to the evaluation of small molecule inhibitors of cytotoxicity, especially those which target either Tau aggregation or the lysosomal/autophagy system.
Collapse
Affiliation(s)
- John R. Veloria
- Department
of Biological Sciences and ‡Department of Chemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Lin Li
- Department
of Biological Sciences and ‡Department of Chemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Gail A. M. Breen
- Department
of Biological Sciences and ‡Department of Chemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Warren J. Goux
- Department
of Biological Sciences and ‡Department of Chemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| |
Collapse
|
38
|
Romine H, Rentschler KM, Smith K, Edwards A, Colvin C, Farizatto K, Pait MC, Butler D, Bahr BA. Potential Alzheimer's Disease Therapeutics Among Weak Cysteine Protease Inhibitors Exhibit Mechanistic Differences Regarding Extent of Cathepsin B Up-Regulation and Ability to Block Calpain. ACTA ACUST UNITED AC 2017; 13:38-59. [PMID: 29805718 DOI: 10.19044/esj.2017.c1p5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Cysteine protease inhibitors have long been part of drug discovery programs for Alzheimer's disease (AD), traumatic brain injury (TBI), and other disorders. Select inhibitors reduce accumulating proteins and AD pathology in mouse models. One such compound, Z-Phe-Aladiazomethylketone (PADK), exhibits a very weak IC50 (9-11 μM) towards cathepsin B (CatB), but curiously PADK causes marked up-regulation of the Aβ-degrading CatB and improves spatial memory. Potential therapeutic and weak inhibitor E64d (14 μM IC50) also up-regulates CatB. PADK and E64d were compared regarding the blockage of calcium-induced cytoskeletal deterioration in brain samples, monitoring the 150-kDa spectrin breakdown product (SBDP) known to be produced by calpain. PADK had little to no effect on SBDP production at 10-100 μM. In contrast, E64d caused a dose-dependent decline in SBDP levels with an IC50 of 3-6 μM, closely matching its reported potency for inhibiting μ-calpain. Calpain also cleaves the cytoskeletal organizing protein gephyrin, producing 49-kDa (GnBDP49) and 18-kDa (GnBDP18) breakdown products. PADK had no apparent effect on calcium-induced gephyrin fragments whereas E64d blocked their production. E64d also protected the parent gephyrin in correspondence with reduced BDP levels. The findings of this study indicate that PADK's positive and selective effects on CatB are consistent with human studies showing exercise elevates CatB and such elevation correlates with improved memory. On the other hand, E64d exhibits both marginal CatB enhancement and potent calpain inhibition. This dual effect may be beneficial for treating AD. Alternatively, the potent action on calpain-related pathology may explain E64d's protection in AD and TBI models.
Collapse
Affiliation(s)
- Heather Romine
- University of North Carolina - Pembroke, Pembroke, North Carolina, USA
| | | | - Kaitlan Smith
- University of North Carolina - Pembroke, Pembroke, North Carolina, USA
| | - Ayanna Edwards
- University of North Carolina - Pembroke, Pembroke, North Carolina, USA
| | - Camille Colvin
- University of North Carolina - Pembroke, Pembroke, North Carolina, USA
| | - Karen Farizatto
- University of North Carolina - Pembroke, Pembroke, North Carolina, USA
| | - Morgan C Pait
- University of North Carolina - Pembroke, Pembroke, North Carolina, USA
| | - David Butler
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, USA
| | - Ben A Bahr
- William C. Friday Laboratory, University of North Carolina - Pembroke, North Carolina, USA
| |
Collapse
|
39
|
β-Amyloid and the Pathomechanisms of Alzheimer's Disease: A Comprehensive View. Molecules 2017; 22:molecules22101692. [PMID: 28994715 PMCID: PMC6151811 DOI: 10.3390/molecules22101692] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/02/2017] [Accepted: 10/06/2017] [Indexed: 01/14/2023] Open
Abstract
Protein dyshomeostasis is the common mechanism of neurodegenerative diseases such as Alzheimer’s disease (AD). Aging is the key risk factor, as the capacity of the proteostasis network declines during aging. Different cellular stress conditions result in the up-regulation of the neurotrophic, neuroprotective amyloid precursor protein (APP). Enzymatic processing of APP may result in formation of toxic Aβ aggregates (β-amyloids). Protein folding is the basis of life and death. Intracellular Aβ affects the function of subcellular organelles by disturbing the endoplasmic reticulum-mitochondria cross-talk and causing severe Ca2+-dysregulation and lipid dyshomeostasis. The extensive and complex network of proteostasis declines during aging and is not able to maintain the balance between production and disposal of proteins. The effectivity of cellular pathways that safeguard cells against proteotoxic stress (molecular chaperones, aggresomes, the ubiquitin-proteasome system, autophagy) declines with age. Chronic cerebral hypoperfusion causes dysfunction of the blood-brain barrier (BBB), and thus the Aβ-clearance from brain-to-blood decreases. Microglia-mediated clearance of Aβ also declines, Aβ accumulates in the brain and causes neuroinflammation. Recognition of the above mentioned complex pathogenesis pathway resulted in novel drug targets in AD research.
Collapse
|
40
|
Victoria GS, Zurzolo C. The spread of prion-like proteins by lysosomes and tunneling nanotubes: Implications for neurodegenerative diseases. J Cell Biol 2017; 216:2633-2644. [PMID: 28724527 PMCID: PMC5584166 DOI: 10.1083/jcb.201701047] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 06/03/2017] [Accepted: 07/05/2017] [Indexed: 11/22/2022] Open
Abstract
Victoria and Zurzolo discuss current evidence for the emerging role of lysosomal damage and tunneling nanotubes in the intercellular propagation of prion and prion-like proteins in neurodegenerative disease. Progression of pathology in neurodegenerative diseases is hypothesized to be a non–cell-autonomous process that may be mediated by the productive spreading of prion-like protein aggregates from a “donor cell” that is the source of misfolded aggregates to an “acceptor cell” in which misfolding is propagated by conversion of the normal protein. Although the proteins involved in the various diseases are unrelated, common pathways appear to be used for their intercellular propagation and spreading. Here, we summarize recent evidence of the molecular mechanisms relevant for the intercellular trafficking of protein aggregates involved in prion, Alzheimer’s, Huntington’s, and Parkinson’s diseases. We focus in particular on the common roles that lysosomes and tunneling nanotubes play in the formation and spreading of prion-like assemblies.
Collapse
Affiliation(s)
| | - Chiara Zurzolo
- Unité de Trafic Membranaire et Pathogénèse, Institut Pasteur, Paris, France
| |
Collapse
|
41
|
Arrestins contribute to amyloid beta-induced cell death via modulation of autophagy and the α7nAch receptor in SH-SY5Y cells. Sci Rep 2017; 7:3446. [PMID: 28611418 PMCID: PMC5469748 DOI: 10.1038/s41598-017-01798-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 04/04/2017] [Indexed: 01/26/2023] Open
Abstract
Amyloid β-protein (Aβ) is believed to contribute to the development of Alzheimer’s disease (AD). Here we showed that Aβ25-35 rapidly caused activation of autophagy, subsequently leading to reduction of autophagy associated with cellular apoptosis. Further investigation revealed that the accumulation of β-arrestin 1 (ARRB1) caused by Aβ25-35 contributed to the induction of autophagic flux. The depletion of ARRB1 led to decreases in the expression of LC3B, Atg7, and Beclin-1, which are essential for the initiation of autophagy. ARRB1 depletion also reduced downstream ERK activity and promoted Aβ25-35-induced cell death. As with ARRB1, transient upregulation of ARRB2 by Aβ25-35 was observed after short treatment durations, whereas genetic reduction of ARRB2 caused a marked increase in the expression of the α7nAch receptor at the cell surface, which resulted in partial reversal of Aβ25-35-induced cell death. Although expression of both ARRB1 and ARRB2 was reduced in serum from patients with AD, the levels of ARRB1 were much lower than those of ARRB2 in AD. Thus, our findings indicate that ARRB1/2 play different roles in Aβ25-35 cytotoxicity, which may provide additional support for exploring the underlying molecular mechanism of AD.
Collapse
|
42
|
Bhounsule AS, Bhatt LK, Prabhavalkar KS, Oza M. Cyclin dependent kinase 5: A novel avenue for Alzheimer’s disease. Brain Res Bull 2017; 132:28-38. [DOI: 10.1016/j.brainresbull.2017.05.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 05/10/2017] [Indexed: 10/19/2022]
|
43
|
Wang Y, MacDonald RG, Thinakaran G, Kar S. Insulin-Like Growth Factor-II/Cation-Independent Mannose 6-Phosphate Receptor in Neurodegenerative Diseases. Mol Neurobiol 2017; 54:2636-2658. [PMID: 26993302 PMCID: PMC5901910 DOI: 10.1007/s12035-016-9849-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 03/09/2016] [Indexed: 12/11/2022]
Abstract
The insulin-like growth factor II/mannose 6-phosphate (IGF-II/M6P) receptor is a multifunctional single transmembrane glycoprotein. Recent studies have advanced our understanding of the structure, ligand-binding properties, and trafficking of the IGF-II/M6P receptor. This receptor has been implicated in a variety of important cellular processes including growth and development, clearance of IGF-II, proteolytic activation of enzymes, and growth factor precursors, in addition to its well-known role in the delivery of lysosomal enzymes. The IGF-II/M6P receptor, distributed widely in the central nervous system, has additional roles in mediating neurotransmitter release and memory enhancement/consolidation, possibly through activating IGF-II-related intracellular signaling pathways. Recent studies suggest that overexpression of the IGF-II/M6P receptor may have an important role in regulating the levels of transcripts and proteins involved in the development of Alzheimer's disease (AD)-the prevalent cause of dementia affecting the elderly population in our society. It is reported that IGF-II/M6P receptor overexpression can increase the levels/processing of amyloid precursor protein leading to the generation of β-amyloid peptide, which is associated with degeneration of neurons and subsequent development of AD pathology. Given the significance of the receptor in mediating the transport and functioning of the lysosomal enzymes, it is being considered for therapeutic delivery of enzymes to the lysosomes to treat lysosomal storage disorders. Notwithstanding these results, additional studies are required to validate and fully characterize the function of the IGF-II/M6P receptor in the normal brain and its involvement in various neurodegenerative disorders including AD. It is also critical to understand the interaction between the IGF-II/M6P receptor and lysosomal enzymes in neurodegenerative processes, which may shed some light on developing approaches to detect and prevent neurodegeneration through the dysfunction of the receptor and the endosomal-lysosomal system.
Collapse
Affiliation(s)
- Y Wang
- Department of Psychiatry, University of Alberta, Edmonton, AB, T6G 2M8, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada
| | - R G MacDonald
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - G Thinakaran
- Departments of Neurobiology, Neurology, and Pathology, The University of Chicago, Chicago, IL, 60637, USA
| | - S Kar
- Department of Psychiatry, University of Alberta, Edmonton, AB, T6G 2M8, Canada.
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada.
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB, T6G 2M8, Canada.
| |
Collapse
|
44
|
Oku Y, Murakami K, Irie K, Hoseki J, Sakai Y. Synthesized Aβ42 Caused Intracellular Oxidative Damage, Leading to Cell Death, via Lysosome Rupture. Cell Struct Funct 2017; 42:71-79. [PMID: 28413178 DOI: 10.1247/csf.17006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Neuronal cellular accumulation of amyloid beta peptide (Aβ) has been implicated in the pathogenesis of Alzheimer's disease (AD). Intracellular accumulation of Aβ42, a toxic form of Aβ, was observed as an early event in AD patients. However, its contribution and the cellular mechanism of cell death remained unclear. We herein revealed the mechanism by which Aβ42 incorporated into cells leads to cell death by using chemically synthesized Aβ42 variants. The Aβ42 variant Aβ42 (E22P) which has an increased tendency to oligomerize, accumulated in lysosomes at an earlier stage than wild-type Aβ42, leading to higher ROS production and lysosomal membrane oxidation, and resulting in cell death. On the other hand, Aβ42 (E22V), which is incapable of oligomerization, did not accumulate in cells or affect the cell viability. Moreover, intracellular localization of EGFP-Galectin-3, a β-galactoside binding lectin, showed that accumulation of oligomerized Aβ42 in lysosomes caused lysosomal membrane permeabilization (LMP). Overexpression of lysosome-localized LAMP1-fused peroxiredoxin 1 and treatment with U18866A, an inhibitor of cholesterol export from lysosomes that causes an increase in lysosomal membrane stability, attenuated Aβ42-mediated LMP and cell death. Our findings show that lysosomal ROS generation by toxic conformer of Aβ led to cell death via LMP, and suggest that these events are potential targets for AD prevention.Key words: Amyloid-beta (Aβ), Cell death, Lysosome, Lysosomal membrane permeabilization, Reactive oxygen species (ROS).
Collapse
Affiliation(s)
- Yuki Oku
- Graduate School of Advanced Integrated Studies, Kyoto University
| | - Kazuma Murakami
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University.,Research Unit for Physiological Chemistry, Kyoto University
| | - Kazuhiro Irie
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University.,Research Unit for Physiological Chemistry, Kyoto University
| | - Jun Hoseki
- Research Unit for Physiological Chemistry, Kyoto University.,Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| | - Yasuyoshi Sakai
- Research Unit for Physiological Chemistry, Kyoto University.,Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University
| |
Collapse
|
45
|
Otomo T, Yoshimori T. Lysophagy: A Method for Monitoring Lysosomal Rupture Followed by Autophagy-Dependent Recovery. Methods Mol Biol 2017; 1594:141-149. [PMID: 28456980 DOI: 10.1007/978-1-4939-6934-0_8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Selective autophagy recognizes specific targets, including damaged mitochondria (mitophagy), aggregated proteins (aggrephagy), and invading bacteria (xenophagy) to engulf by isolation membrane, and degrades toxic materials within lysosomes. We recently revealed that a membrane-damaged lysosome itself also becomes a target of autophagy and named this process lysophagy. In this chapter, we describe methods for monitoring lysophagy; detecting lysosomal damage by staining of galectin and study the subsequent autophagic process in cultured mammalian cells.
Collapse
Affiliation(s)
- Takanobu Otomo
- Department of Genetics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, Japan
- Laboratory of Intracellular Membrane Dynamics, Osaka University Graduate School of Frontier Biosciences, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
- Research Center for Autophagy, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Tamotsu Yoshimori
- Department of Genetics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, Japan.
- Laboratory of Intracellular Membrane Dynamics, Osaka University Graduate School of Frontier Biosciences, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
- Research Center for Autophagy, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| |
Collapse
|
46
|
Lysosomal Re-acidification Prevents Lysosphingolipid-Induced Lysosomal Impairment and Cellular Toxicity. PLoS Biol 2016; 14:e1002583. [PMID: 27977664 PMCID: PMC5169359 DOI: 10.1371/journal.pbio.1002583] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 11/11/2016] [Indexed: 12/20/2022] Open
Abstract
Neurodegenerative lysosomal storage disorders (LSDs) are severe and untreatable, and mechanisms underlying cellular dysfunction are poorly understood. We found that toxic lipids relevant to three different LSDs disrupt multiple lysosomal and other cellular functions. Unbiased drug discovery revealed several structurally distinct protective compounds, approved for other uses, that prevent lysosomal and cellular toxicities of these lipids. Toxic lipids and protective agents show unexpected convergence on control of lysosomal pH and re-acidification as a critical component of toxicity and protection. In twitcher mice (a model of Krabbe disease [KD]), a central nervous system (CNS)-penetrant protective agent rescued myelin and oligodendrocyte (OL) progenitors, improved motor behavior, and extended lifespan. Our studies reveal shared principles relevant to several LSDs, in which diverse cellular and biochemical disruptions appear to be secondary to disruption of lysosomal pH regulation by specific lipids. These studies also provide novel protective strategies that confer therapeutic benefits in a mouse model of a severe LSD.
Collapse
|
47
|
Eitan E, Suire C, Zhang S, Mattson MP. Impact of lysosome status on extracellular vesicle content and release. Ageing Res Rev 2016; 32:65-74. [PMID: 27238186 DOI: 10.1016/j.arr.2016.05.001] [Citation(s) in RCA: 153] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 05/09/2016] [Accepted: 05/09/2016] [Indexed: 12/18/2022]
Abstract
Extracellular vesicles (EVs) are nanoscale size bubble-like membranous structures released from cells. EVs contain RNA, lipids and proteins and are thought to serve various roles including intercellular communication and removal of misfolded proteins. The secretion of misfolded and aggregated proteins in EVs may be a cargo disposal alternative to the autophagy-lysosomal and ubiquitin-proteasome pathways. In this review we will discuss the importance of lysosome functionality for the regulation of EV secretion and content. Exosomes are a subtype of EVs that are released by the fusion of multivesicular bodies (MVB) with the plasma membrane. MVBs can also fuse with lysosomes, and the trafficking pathway of MVBs can therefore determine whether or not exosomes are released from cells. Here we summarize data from studies of the effects of lysosome inhibition on the secretion of EVs and on the possibility that cells compensate for lysosome malfunction by disposal of potentially toxic cargos in EVs. A better understanding of the molecular mechanisms that regulate trafficking of MVBs to lysosomes and the plasma membrane may advance an understanding of diseases in which pathogenic proteins, lipids or infectious agents accumulate within or outside of cells.
Collapse
|
48
|
The Role of Neutrophil Proteins on the Amyloid Beta-RAGE Axis. PLoS One 2016; 11:e0163330. [PMID: 27676391 PMCID: PMC5038948 DOI: 10.1371/journal.pone.0163330] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 09/06/2016] [Indexed: 01/11/2023] Open
Abstract
We previously showed an elevated expression of the neutrophil protein, cationic antimicrobial protein of 37kDa (CAP37), in brains of patients with Alzheimer’s disease (AD), suggesting that CAP37 could be involved in AD pathogenesis. The first step in determining how CAP37 might contribute to AD pathogenesis was to identify the receptor through which it induces cell responses. To identify a putative receptor, we performed GAMMA analysis to determine genes that positively correlated with CAP37 in terms of expression. Positive correlations with ligands for the receptor for advanced glycation end products (RAGE) were observed. Additionally, CAP37 expression positively correlated with two other neutrophil proteins, neutrophil elastase and cathepsin G. Enzyme-linked immunosorbent assays (ELISAs) demonstrated an interaction between CAP37, neutrophil elastase, and cathepsin G with RAGE. Amyloid beta 1–42 (Aβ1–42), a known RAGE ligand, accumulates in AD brains and interacts with RAGE, contributing to Aβ1–42 neurotoxicity. We questioned whether the binding of CAP37, neutrophil elastase and/or cathepsin G to RAGE could interfere with Aβ1–42 binding to RAGE. Using ELISAs, we determined that CAP37 and neutrophil elastase inhibited binding of Aβ1–42 to RAGE, and this effect was reversed by protease inhibitors in the case of neutrophil elastase. Since neutrophil elastase and cathepsin G have enzymatic activity, mass spectrometry was performed to determine the proteolytic activity of all three neutrophil proteins on Aβ1–42. All three neutrophil proteins bound to Aβ1–42 with different affinities and cleaved Aβ1–42 with different kinetics and substrate specificities. We posit that these neutrophil proteins could modulate neurotoxicity in AD by cleaving Aβ1–42 and influencing the Aβ1–42 –RAGE interaction. Further studies will be required to determine the biological significance of these effects and their relevance in neurodegenerative diseases such as AD. Our findings identify a novel area of study that underscores the importance of neutrophils and neutrophil proteins in neuroinflammatory diseases such as AD.
Collapse
|
49
|
Zhang Z, Xie M, Ye K. Asparagine endopeptidase is an innovative therapeutic target for neurodegenerative diseases. Expert Opin Ther Targets 2016; 20:1237-45. [PMID: 27115710 DOI: 10.1080/14728222.2016.1182990] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Asparagine endopeptidase (AEP) is a pH-dependent endolysosomal cysteine protease that cleaves its substrates after asparagine residues. Our most recent study identifies that it possesses the delta-secretase activity, and that it is implicated in numerous neurological diseases such as Alzheimer's disease (AD) and stroke. Accumulating evidence supports that the inhibition of AEP exhibits beneficial effects for treating these devastating diseases. AREAS COVERED Based on recent evidence, it is clear that AEP cleaves its substrate, such as amyloid precursor protein (APP), tau and SET, and plays a critical role in neuronal cell death in various neurodegenerative diseases and stroke. In this article, the basic biology of AEP, its knockout phenotypes in mouse models, its substrates in neurodegenerative diseases, and its small peptidyl inhibitors and prodrugs are discussed. In addition, we discuss the potential of AEP as a novel therapeutic target for neurodegenerative diseases. EXPERT OPINION AEP plays a unique role in numerous biological processes, depending on both pH and context. Most striking is our most recent finding; that AEP is activated in an age-dependent manner and simultaneously cleaves both APP and tau, thereby unifying both major pathological events in AD. Thus, AEP acts as an innovative trigger for neurodegenerative diseases. Inhibition of AEP will provide a disease-modifying treatment for neurodegenerative diseases including AD.
Collapse
Affiliation(s)
- Zhentao Zhang
- a Department of Neurology , Renmin Hospital of Wuhan University , Wuhan , China.,b Department of Pathology and Laboratory Medicine , Emory University School of Medicine , Atlanta , GA , USA
| | - Manling Xie
- b Department of Pathology and Laboratory Medicine , Emory University School of Medicine , Atlanta , GA , USA
| | - Keqiang Ye
- b Department of Pathology and Laboratory Medicine , Emory University School of Medicine , Atlanta , GA , USA
| |
Collapse
|
50
|
de Castro MAG, Bunt G, Wouters FS. Cathepsin B launches an apoptotic exit effort upon cell death-associated disruption of lysosomes. Cell Death Discov 2016; 2:16012. [PMID: 27551506 PMCID: PMC4979493 DOI: 10.1038/cddiscovery.2016.12] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 01/18/2016] [Accepted: 01/21/2016] [Indexed: 01/13/2023] Open
Abstract
The release of cathepsin proteases from disrupted lysosomes results in lethal cellular autodigestion. Lysosomal disruption-related cell death is highly variable, showing both apoptotic and necrotic outcomes. As the substrate spectrum of lysosomal proteases encompasses the apoptosis-regulating proteins of the Bcl-2 family, their degradation could influence the cell death outcome upon lysosomal disruption. We used Förster resonance energy transfer (FRET)-based biosensors to image the real-time degradation of the Bcl-2-family members, Bcl-xl, Bax and Bid, in living cells undergoing lysosomal lysis and identified an early chain of proteolytic events, initiated by the release of cathepsin B, which directs cells toward apoptosis. In this apoptotic exit strategy, cathepsin B’s proteolytic activity results in apoptosis-inducing Bid and removes apoptosis-preventing Bcl-xl. Cathepsin B furthermore appears to degrade a cystein protease that would otherwise have eliminated apoptosis-supporting Bax, indirectly keeping cellular levels of the Bax protein up. The concerted effort of these three early events shifts the balance of cell fate away from necrosis and toward apoptosis.
Collapse
Affiliation(s)
- M A G de Castro
- Laboratory for Molecular and Cellular Systems, Institute of Neuropathology, University Medical Center Göttingen , Göttingen, Germany
| | - G Bunt
- Laboratory for Molecular and Cellular Systems, Institute of Neuropathology, University Medical Center Göttingen, Göttingen, Germany; Clinical Optical Microscopy, Institute of Neuropathology, University Medical Center Göttingen, Göttingen, Germany
| | - F S Wouters
- Laboratory for Molecular and Cellular Systems, Institute of Neuropathology, University Medical Center Göttingen, Göttingen, Germany; Centre for Nanoscale Molecular Physiology of the Brain (CNMPB), Göttingen, Germany
| |
Collapse
|