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Reich M, Simon MJ, Polke B, Paris I, Werner G, Schrader C, Spieth L, Davis SS, Robinson S, de Melo GL, Schlaphoff L, Buschmann K, Berghoff S, Logan T, Nuscher B, de Weerd L, Edbauer D, Simons M, Suh JH, Sandmann T, Kariolis MS, DeVos SL, Lewcock JW, Paquet D, Capell A, Di Paolo G, Haass C. Peripheral expression of brain-penetrant progranulin rescues pathologies in mouse models of frontotemporal lobar degeneration. Sci Transl Med 2024; 16:eadj7308. [PMID: 38838131 DOI: 10.1126/scitranslmed.adj7308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 05/10/2024] [Indexed: 06/07/2024]
Abstract
Progranulin (PGRN) haploinsufficiency is a major risk factor for frontotemporal lobar degeneration with TAR DNA-binding protein 43 (TDP-43) pathology (FTLD-GRN). Multiple therapeutic strategies are in clinical development to restore PGRN in the CNS, including gene therapy. However, a limitation of current gene therapy approaches aimed to alleviate FTLD-associated pathologies may be their inefficient brain exposure and biodistribution. We therefore developed an adeno-associated virus (AAV) targeting the liver (L) to achieve sustained peripheral expression of a transferrin receptor (TfR) binding, brain-penetrant (b) PGRN variant [AAV(L):bPGRN] in two mouse models of FTLD-GRN, namely, Grn knockout and GrnxTmem106b double knockout mice. This therapeutic strategy avoids potential safety and biodistribution issues of CNS-administered AAVs and maintains sustained concentrations of PGRN in the brain after a single dose. AAV(L):bPGRN treatment reduced several FTLD-GRN-associated pathologies including severe motor function deficits, aberrant TDP-43 phosphorylation, dysfunctional protein degradation, lipid metabolism, gliosis, and neurodegeneration in the brain. The potential translatability of our findings was tested in an in vitro model using cocultured human induced pluripotent stem cell (hiPSC)-derived microglia lacking PGRN and TMEM106B and wild-type hiPSC-derived neurons. As in mice, aberrant TDP-43, lysosomal dysfunction, and neuronal loss were ameliorated after treatment with exogenous TfR-binding protein transport vehicle fused to PGRN (PTV:PGRN). Together, our studies suggest that peripherally administered brain-penetrant PGRN replacement strategies ameliorate FTLD-GRN relevant phenotypes including TDP-43 pathology, neurodegeneration, and behavioral deficits. Our data provide preclinical proof of concept for the use of this AAV platform for treatment of FTLD-GRN and potentially other CNS disorders.
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Affiliation(s)
- Marvin Reich
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Graduate School of Systemic Neurosciences (GSN), LMU Munich, 82152 Planegg, Germany
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, 81377 Munich, Germany
| | - Matthew J Simon
- Denali Therapeutics Inc., South San Francisco, CA 94080, USA
| | - Beate Polke
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | - Iñaki Paris
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | - Georg Werner
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | - Christian Schrader
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | - Lena Spieth
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Institute of Neuronal Cell Biology, Technical University Munich, 80802 Munich, Germany
- Max Planck Institute for Multidisciplinary Sciences, 37077 Göttingen, Germany
| | - Sonnet S Davis
- Denali Therapeutics Inc., South San Francisco, CA 94080, USA
| | - Sophie Robinson
- Graduate School of Systemic Neurosciences (GSN), LMU Munich, 82152 Planegg, Germany
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, 81377 Munich, Germany
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | | | - Lennart Schlaphoff
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Graduate School of Systemic Neurosciences (GSN), LMU Munich, 82152 Planegg, Germany
- Institute of Neuronal Cell Biology, Technical University Munich, 80802 Munich, Germany
| | - Katrin Buschmann
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | - Stefan Berghoff
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Institute of Neuronal Cell Biology, Technical University Munich, 80802 Munich, Germany
- Max Planck Institute for Multidisciplinary Sciences, 37077 Göttingen, Germany
| | - Todd Logan
- Denali Therapeutics Inc., South San Francisco, CA 94080, USA
| | - Brigitte Nuscher
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | - Lis de Weerd
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
| | - Dieter Edbauer
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Munich Cluster for Systems Neurology (Synergy), 81377 Munich, Germany
| | - Mikael Simons
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, 81377 Munich, Germany
- Institute of Neuronal Cell Biology, Technical University Munich, 80802 Munich, Germany
- Munich Cluster for Systems Neurology (Synergy), 81377 Munich, Germany
| | - Jung H Suh
- Denali Therapeutics Inc., South San Francisco, CA 94080, USA
| | - Thomas Sandmann
- Denali Therapeutics Inc., South San Francisco, CA 94080, USA
| | | | - Sarah L DeVos
- Denali Therapeutics Inc., South San Francisco, CA 94080, USA
| | | | - Dominik Paquet
- Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, 81377 Munich, Germany
- Munich Cluster for Systems Neurology (Synergy), 81377 Munich, Germany
| | - Anja Capell
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
| | | | - Christian Haass
- German Center for Neurodegenerative Diseases (DZNE), 81377 Munich, Germany
- Metabolic Biochemistry, Biomedical Centre (BMC), Faculty of Medicine, LMU Munich, 81377 Munich, Germany
- Munich Cluster for Systems Neurology (Synergy), 81377 Munich, Germany
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2
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Panikulam S, Hanke A, Kroener F, Karle A, Anderka O, Villiger TK, Lebesgue N. Host cell protein networks as a novel co-elution mechanism during protein A chromatography. Biotechnol Bioeng 2024; 121:1716-1728. [PMID: 38454640 DOI: 10.1002/bit.28678] [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: 11/03/2023] [Revised: 01/29/2024] [Accepted: 02/10/2024] [Indexed: 03/09/2024]
Abstract
Host cell proteins (HCPs) are process-related impurities of therapeutic proteins produced in for example, Chinese hamster ovary (CHO) cells. Protein A affinity chromatography is the initial capture step to purify monoclonal antibodies or Fc-based proteins and is most effective for HCP removal. Previously proposed mechanisms that contribute to co-purification of HCPs with the therapeutic protein are either HCP-drug association or leaching from chromatin heteroaggregates. In this study, we analyzed protein A eluates of 23 Fc-based proteins by LC-MS/MS to determine their HCP content. The analysis revealed a high degree of heterogeneity in the number of HCPs identified in the different protein A eluates. Among all identified HCPs, the majority co-eluted with less than three Fc-based proteins indicating a drug-specific co-purification for most HCPs. Only ten HCPs co-purified with over 50% of the 23 Fc-based proteins. A correlation analysis of HCPs identified across multiple protein A eluates revealed their co-elution as HCP groups. Functional annotation and protein interaction analysis confirmed that some HCP groups are associated with protein-protein interaction networks. Here, we propose an additional mechanism for HCP co-elution involving protein-protein interactions within functional networks. Our findings may help to guide cell line development and to refine downstream purification strategies.
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Affiliation(s)
- Sherin Panikulam
- Institute of Pharma Technology, University of Applied Sciences Northwestern Switzerland, Muttenz, Switzerland
- Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland
| | - Alexander Hanke
- Analytical Development and Characterization, Biopharmaceutical Product and Process Development, Technical Research and Development, Novartis Pharma AG, Basel, Switzerland
| | - Frieder Kroener
- Analytical Development and Characterization, Biopharmaceutical Product and Process Development, Technical Research and Development, Novartis Pharma AG, Basel, Switzerland
| | - Anette Karle
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, Basel, Switzerland
| | - Oliver Anderka
- Analytical Development and Characterization, Biopharmaceutical Product and Process Development, Technical Research and Development, Novartis Pharma AG, Basel, Switzerland
| | - Thomas K Villiger
- Institute of Pharma Technology, University of Applied Sciences Northwestern Switzerland, Muttenz, Switzerland
| | - Nicolas Lebesgue
- Analytical Development and Characterization, Biopharmaceutical Product and Process Development, Technical Research and Development, Novartis Pharma AG, Basel, Switzerland
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Rosenthal ZC, Fass DM, Payne NC, She A, Patnaik D, Hennig KM, Tesla R, Werthmann GC, Guhl C, Reis SA, Wang X, Chen Y, Placzek M, Williams NS, Hooker J, Herz J, Mazitschek R, Haggarty SJ. Epigenetic modulation through BET bromodomain inhibitors as a novel therapeutic strategy for progranulin-deficient frontotemporal dementia. Sci Rep 2024; 14:9064. [PMID: 38643236 PMCID: PMC11032351 DOI: 10.1038/s41598-024-59110-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 04/08/2024] [Indexed: 04/22/2024] Open
Abstract
Frontotemporal dementia (FTD) is a debilitating neurodegenerative disorder with currently no disease-modifying treatment options available. Mutations in GRN are one of the most common genetic causes of FTD, near ubiquitously resulting in progranulin (PGRN) haploinsufficiency. Small molecules that can restore PGRN protein to healthy levels in individuals bearing a heterozygous GRN mutation may thus have therapeutic value. Here, we show that epigenetic modulation through bromodomain and extra-terminal domain (BET) inhibitors (BETi) potently enhance PGRN protein levels, both intracellularly and secreted forms, in human central nervous system (CNS)-relevant cell types, including in microglia-like cells. In terms of potential for disease modification, we show BETi treatment effectively restores PGRN levels in neural cells with a GRN mutation known to cause PGRN haploinsufficiency and FTD. We demonstrate that BETi can rapidly and durably enhance PGRN in neural progenitor cells (NPCs) in a manner dependent upon BET protein expression, suggesting a gain-of-function mechanism. We further describe a CNS-optimized BETi chemotype that potently engages endogenous BRD4 and enhances PGRN expression in neuronal cells. Our results reveal a new epigenetic target for treating PGRN-deficient forms of FTD and provide mechanistic insight to aid in translating this discovery into therapeutics.
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Affiliation(s)
- Zachary C Rosenthal
- Chemical Neurobiology Laboratory, Precision Therapeutics Unit, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA
- Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Daniel M Fass
- Chemical Neurobiology Laboratory, Precision Therapeutics Unit, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA
| | - N Connor Payne
- Department of Chemistry & Chemical Biology, Harvard University, Cambridge, MA, USA
- Center for Systems Biology, Massachusetts General Hospital, Boston, MA, USA
- Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Angela She
- Chemical Neurobiology Laboratory, Precision Therapeutics Unit, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA
| | - Debasis Patnaik
- Chemical Neurobiology Laboratory, Precision Therapeutics Unit, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA
| | - Krista M Hennig
- Chemical Neurobiology Laboratory, Precision Therapeutics Unit, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA
| | - Rachel Tesla
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Center for Translational Neurodegeneration Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Gordon C Werthmann
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Center for Translational Neurodegeneration Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Charlotte Guhl
- Faculty of Chemistry and Earth Sciences, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University Jena, Jena, Germany
| | - Surya A Reis
- Chemical Neurobiology Laboratory, Precision Therapeutics Unit, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA
| | - Xiaoyu Wang
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yueting Chen
- Department of Radiology, Harvard Medical School, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA
| | - Michael Placzek
- Department of Radiology, Harvard Medical School, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA
| | - Noelle S Williams
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jacob Hooker
- Department of Radiology, Harvard Medical School, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, USA
| | - Joachim Herz
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Center for Translational Neurodegeneration Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ralph Mazitschek
- Center for Systems Biology, Massachusetts General Hospital, Boston, MA, USA
- Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Stephen J Haggarty
- Chemical Neurobiology Laboratory, Precision Therapeutics Unit, Center for Genomic Medicine, Departments of Neurology and Psychiatry, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA.
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Sun MA, Yao H, Yang Q, Pirozzi CJ, Chandramohan V, Ashley DM, He Y. Gene expression analysis suggests immunosuppressive roles of endolysosomes in glioblastoma. PLoS One 2024; 19:e0299820. [PMID: 38507437 PMCID: PMC10954093 DOI: 10.1371/journal.pone.0299820] [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: 10/17/2023] [Accepted: 02/15/2024] [Indexed: 03/22/2024] Open
Abstract
Targeting endolysosomes is a strategy extensively pursued for treating cancers, including glioblastomas (GBMs), on the basis that the intact function of these subcellular organelles is key to tumor cell autophagy and survival. Through gene expression analyses and cell type abundance estimation in GBMs, we showed that genes associated with the endolysosomal machinery are more prominently featured in non-tumor cells in GBMs than in tumor cells, and that tumor-associated macrophages represent the primary immune cell type that contributes to this trend. Further analyses found an enrichment of endolysosomal pathway genes in immunosuppressive (pro-tumorigenic) macrophages, such as M2-like macrophages or those associated with worse prognosis in glioma patients, but not in those linked to inflammation (anti-tumorigenic). Specifically, genes critical to the hydrolysis function of endolysosomes, including progranulin and cathepsins, were among the most positively correlated with immunosuppressive macrophages, and elevated expression of these genes is associated with worse patient survival in GBMs. Together, these results implicate the hydrolysis function of endolysosomes in shaping the immunosuppressive microenvironment of GBM. We propose that targeting endolysosomes, in addition to its detrimental effects on tumor cells, can be leveraged for modulating immunosuppression to render GBMs more amenable to immunotherapies.
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Affiliation(s)
- Michael A. Sun
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States of America
- Department of Pathology, Duke University Medical Center, Durham, NC, United States of America
- Pathology Graduate Program, Duke University Medical Center, Durham, NC, United States of America
| | - Haipei Yao
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States of America
- Department of Pathology, Duke University Medical Center, Durham, NC, United States of America
- Pathology Graduate Program, Duke University Medical Center, Durham, NC, United States of America
| | - Qing Yang
- Duke University School of Nursing, Durham, NC, United States of America
| | - Christopher J. Pirozzi
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States of America
- Department of Pathology, Duke University Medical Center, Durham, NC, United States of America
| | - Vidyalakshmi Chandramohan
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States of America
- Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States of America
| | - David M. Ashley
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States of America
- Department of Neurosurgery, Duke University Medical Center, Durham, NC, United States of America
| | - Yiping He
- The Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, United States of America
- Department of Pathology, Duke University Medical Center, Durham, NC, United States of America
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Kim MJ, Kim S, Reinheckel T, Krainc D. Inhibition of cysteine protease cathepsin L increases the level and activity of lysosomal glucocerebrosidase. JCI Insight 2024; 9:e169594. [PMID: 38329128 PMCID: PMC10967467 DOI: 10.1172/jci.insight.169594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 12/13/2023] [Indexed: 02/09/2024] Open
Abstract
The glucocerebrosidase (GCase) encoded by the GBA1 gene hydrolyzes glucosylceramide (GluCer) to ceramide and glucose in lysosomes. Homozygous or compound heterozygous GBA1 mutations cause the lysosomal storage disease Gaucher disease (GD) due to severe loss of GCase activity. Loss-of-function variants in the GBA1 gene are also the most common genetic risk factor for Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Restoring lysosomal GCase activity represents an important therapeutic approach for GBA1-associated diseases. We hypothesized that increasing the stability of lysosomal GCase protein could correct deficient GCase activity in these conditions. However, it remains unknown how GCase stability is regulated in the lysosome. We found that cathepsin L, a lysosomal cysteine protease, cleaves GCase and regulates its stability. In support of these data, GCase protein was elevated in the brain of cathepsin L-KO mice. Chemical inhibition of cathepsin L increased both GCase levels and activity in fibroblasts from patients with GD. Importantly, inhibition of cathepsin L in dopaminergic neurons from a patient GBA1-PD led to increased GCase levels and activity as well as reduced phosphorylated α-synuclein. These results suggest that targeting cathepsin L-mediated GCase degradation represents a potential therapeutic strategy for GCase deficiency in PD and related disorders that exhibit decreased GCase activity.
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Affiliation(s)
- Myung Jong Kim
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Soojin Kim
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Thomas Reinheckel
- Institute of Molecular Medicine and Cell Research, Medical Faculty and BIOSS Centre for Biological Signaling Studies, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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Gillett DA, Wallings RL, Uriarte Huarte O, Tansey MG. Progranulin and GPNMB: interactions in endo-lysosome function and inflammation in neurodegenerative disease. J Neuroinflammation 2023; 20:286. [PMID: 38037070 PMCID: PMC10688479 DOI: 10.1186/s12974-023-02965-w] [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: 09/22/2023] [Accepted: 11/21/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND Alterations in progranulin (PGRN) expression are associated with multiple neurodegenerative diseases (NDs), including frontotemporal dementia (FTD), Alzheimer's disease (AD), Parkinson's disease (PD), and lysosomal storage disorders (LSDs). Recently, the loss of PGRN was shown to result in endo-lysosomal system dysfunction and an age-dependent increase in the expression of another protein associated with NDs, glycoprotein non-metastatic B (GPNMB). MAIN BODY It is unclear what role GPNMB plays in the context of PGRN insufficiency and how they interact and contribute to the development or progression of NDs. This review focuses on the interplay between these two critical proteins within the context of endo-lysosomal health, immune function, and inflammation in their contribution to NDs. SHORT CONCLUSION PGRN and GPNMB are interrelated proteins that regulate disease-relevant processes and may have value as therapeutic targets to delay disease progression or extend therapeutic windows.
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Affiliation(s)
- Drew A Gillett
- Center for Translational Research in Neurodegenerative Disease (CTRND), University of Florida, Gainesville, FL, USA
- Department of Neuroscience, University of Florida, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Rebecca L Wallings
- Center for Translational Research in Neurodegenerative Disease (CTRND), University of Florida, Gainesville, FL, USA
- Department of Neuroscience, University of Florida, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Oihane Uriarte Huarte
- Center for Translational Research in Neurodegenerative Disease (CTRND), University of Florida, Gainesville, FL, USA
- Department of Neuroscience, University of Florida, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Malú Gámez Tansey
- Center for Translational Research in Neurodegenerative Disease (CTRND), University of Florida, Gainesville, FL, USA.
- Department of Neuroscience, University of Florida, Gainesville, FL, USA.
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
- Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, USA.
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Hasan S, Fernandopulle MS, Humble SW, Frankenfield AM, Li H, Prestil R, Johnson KR, Ryan BJ, Wade-Martins R, Ward ME, Hao L. Multi-modal proteomic characterization of lysosomal function and proteostasis in progranulin-deficient neurons. Mol Neurodegener 2023; 18:87. [PMID: 37974165 PMCID: PMC10655356 DOI: 10.1186/s13024-023-00673-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 10/25/2023] [Indexed: 11/19/2023] Open
Abstract
BACKGROUND Progranulin (PGRN) is a lysosomal glycoprotein implicated in various neurodegenerative diseases, including frontotemporal dementia and neuronal ceroid lipofuscinosis. Over 70 mutations discovered in the GRN gene all result in reduced expression of the PGRN protein. Genetic and functional studies point toward a regulatory role for PGRN in lysosome functions. However, the detailed molecular function of PGRN within lysosomes and the impact of PGRN deficiency on lysosomes remain unclear. METHODS We developed multifaceted proteomic techniques to characterize the dynamic lysosomal biology in living human neurons and fixed mouse brain tissues. Using lysosome proximity labeling and immuno-purification of intact lysosomes, we characterized lysosome compositions and interactome in both human induced pluripotent stem cell (iPSC)-derived glutamatergic neurons (i3Neurons) and mouse brains. Using dynamic stable isotope labeling by amino acids in cell culture (dSILAC) proteomics, we measured global protein half-lives in human i3Neurons for the first time. RESULTS Leveraging the multi-modal proteomics and live-cell imaging techniques, we comprehensively characterized how PGRN deficiency changes the molecular and functional landscape of neuronal lysosomes. We found that PGRN loss impairs the lysosome's degradative capacity with increased levels of v-ATPase subunits on the lysosome membrane, increased hydrolases within the lysosome, altered protein regulations related to lysosomal transport, and elevated lysosomal pH. Consistent with impairments in lysosomal function, GRN-null i3Neurons and frontotemporal dementia patient-derived i3Neurons carrying GRN mutation showed pronounced alterations in protein turnover, such as cathepsins and proteins related to supramolecular polymerization and inherited neurodegenerative diseases. CONCLUSION This study suggested PGRN as a critical regulator of lysosomal pH and degradative capacity, which influences global proteostasis in neurons. Beyond the study of progranulin deficiency, these newly developed proteomic methods in neurons and brain tissues provided useful tools and data resources for the field to study the highly dynamic neuronal lysosome biology.
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Affiliation(s)
- Saadia Hasan
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Department of Neurodegenerative Disease, UK Dementia Research Institute, Institute of Neurology, University College London, London, UK
- Augusta University, University of Georgia Medical Partnership, Athens, GA, USA
| | - Michael S Fernandopulle
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
- Medical Scientist Training Program, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Stewart W Humble
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK
| | | | - Haorong Li
- Department of Chemistry, George Washington University, Washington, DC, USA
| | - Ryan Prestil
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Kory R Johnson
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Brent J Ryan
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK
| | - Richard Wade-Martins
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK
| | - Michael E Ward
- National Institute of Neurological, Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA.
| | - Ling Hao
- Department of Chemistry, George Washington University, Washington, DC, USA.
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Kaplelach AK, Fox SN, Cook AK, Hall JA, Dannemiller RS, Jaunarajs KL, Arrant AE. Regulation of extracellular progranulin in medial prefrontal cortex. Neurobiol Dis 2023; 188:106326. [PMID: 37838007 PMCID: PMC10682954 DOI: 10.1016/j.nbd.2023.106326] [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: 08/04/2023] [Revised: 09/28/2023] [Accepted: 10/11/2023] [Indexed: 10/16/2023] Open
Abstract
Progranulin is a secreted pro-protein that has anti-inflammatory and neurotrophic effects and is necessary for maintaining lysosomal function. Mutations in progranulin (GRN) are a major cause of frontotemporal dementia. Most pathogenic GRN mutations cause progranulin haploinsufficiency, so boosting progranulin levels is a promising therapeutic strategy. Progranulin is constitutively secreted, then taken up and trafficked to lysosomes. Before being taken up from the extracellular space, progranulin interacts with receptors that may mediate anti-inflammatory and growth factor-like effects. Modifying progranulin trafficking is a viable approach to boosting progranulin, but progranulin secretion and uptake by cells in the brain is poorly understood and may involve distinct mechanisms from other parts of the body. Understanding the cell types and processes that regulate extracellular progranulin in the brain could provide insight into progranulin's mechanism of action and inform design of progranulin-boosting therapies. To address this question we used microdialysis to measure progranulin in interstitial fluid (ISF) of mouse medial prefrontal cortex (mPFC). Grn+/- mice had approximately 50% lower ISF progranulin than wild-type mice, matching the reduction of progranulin in cortical tissue. Fluorescent in situ hybridization and immunofluorescence confirmed that microglia and neurons are the major progranulin-expressing cell types in the mPFC. Studies of conditional microglial (Mg-KO) and neuronal (N-KO) Grn knockout mice revealed that loss of progranulin from either cell type results in approximately 50% reduction in ISF progranulin. LPS injection (i.p.) produced an acute increase in ISF progranulin in mPFC. Depolarizing cells with KCl increased ISF progranulin, but this response was not altered in N-KO mice, indicating progranulin secretion by non-neuronal cells. Increasing neuronal activity with picrotoxin did not increase ISF progranulin. These data indicate that microglia and neurons are the source of most ISF progranulin in mPFC, with microglia likely secreting more progranulin per cell than neurons. The acute increase in ISF progranulin after LPS treatment is consistent with a role for extracellular progranulin in regulating inflammation, and may have been driven by microglia or peripheral immune cells. Finally, these data indicate that mPFC neurons engage in constitutive progranulin secretion that is not acutely changed by neuronal activity.
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Affiliation(s)
- Azariah K Kaplelach
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Stephanie N Fox
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Anna K Cook
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Justin A Hall
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Ryan S Dannemiller
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Karen L Jaunarajs
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Andrew E Arrant
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA.
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9
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T. Vicente C, Perneel J, Wynants S, Heeman B, Van den Broeck M, Baker M, Cheung S, Faura J, Mackenzie IRA, Rademakers R. C-terminal TMEM106B fragments in human brain correlate with disease-associated TMEM106B haplotypes. Brain 2023; 146:4055-4064. [PMID: 37100087 PMCID: PMC10545506 DOI: 10.1093/brain/awad133] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/03/2023] [Accepted: 04/13/2023] [Indexed: 04/28/2023] Open
Abstract
Transmembrane protein 106B (TMEM106B) is a tightly regulated glycoprotein predominantly localized to endosomes and lysosomes. Genetic studies have implicated TMEM106B haplotypes in the development of multiple neurodegenerative diseases with the strongest effect in frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP), especially in progranulin (GRN) mutation carriers. Recently, cryo-electron microscopy studies showed that a C-terminal fragment (CTF) of TMEM106B (amino acid residues 120-254) forms amyloid fibrils in the brain of patients with FTLD-TDP, but also in brains with other neurodegenerative conditions and normal ageing brain. The functional implication of these fibrils and their relationship to the disease-associated TMEM106B haplotype remain unknown. We performed immunoblotting using a newly developed antibody to detect TMEM106B CTFs in the sarkosyl-insoluble fraction of post-mortem human brain tissue from patients with different proteinopathies (n = 64) as well as neuropathologically normal individuals (n = 10) and correlated the results with age and TMEM106B haplotype. We further compared the immunoblot results with immunohistochemical analyses performed in the same study population. Immunoblot analysis showed the expected ∼30 kDa band in the sarkosyl-insoluble fraction of frontal cortex tissue in at least some individuals with each of the conditions evaluated. Most patients with GRN mutations showed an intense band representing TMEM106B CTF, whereas in most neurologically normal individuals it was absent or much weaker. In the overall cohort, the presence of TMEM106B CTFs correlated strongly with both age (rs = 0.539, P < 0.001) and the presence of the TMEM106B risk haplotype (rs = 0.469, P < 0.001). Although there was a strong overall correlation between the results of immunoblot and immunohistochemistry (rs = 0.662, P < 0.001), 27 cases (37%) were found to have higher amounts of TMEM106B CTFs detected by immunohistochemistry, including most of the older individuals who were neuropathologically normal and individuals who carried two protective TMEM106B haplotypes. Our findings suggest that the formation of sarkosyl-insoluble TMEM106B CTFs is an age-related feature which is modified by TMEM106B haplotype, potentially underlying its disease-modifying effect. The discrepancies between immunoblot and immunohistochemistry in detecting TMEM106B pathology suggests the existence of multiple species of TMEM106B CTFs with possible biological relevance and disease implications.
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Affiliation(s)
- Cristina T. Vicente
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Jolien Perneel
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Sarah Wynants
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Bavo Heeman
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Marleen Van den Broeck
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Matt Baker
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32233, USA
| | - Simon Cheung
- Department of Pathology, Vancouver Coastal Health, Vancouver, BC V5Z1M9, Canada
| | - Júlia Faura
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
| | - Ian R A Mackenzie
- Department of Pathology, Vancouver Coastal Health, Vancouver, BC V5Z1M9, Canada
- Department of Pathology, University of British Columbia, Vancouver, BC V6T 1Z7, Canada
| | - Rosa Rademakers
- VIB Center for Molecular Neurology, University of Antwerp, 2610, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, 2610, Antwerp, Belgium
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32233, USA
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10
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Jiao HS, Yuan P, Yu JT. TMEM106B aggregation in neurodegenerative diseases: linking genetics to function. Mol Neurodegener 2023; 18:54. [PMID: 37563705 PMCID: PMC10413548 DOI: 10.1186/s13024-023-00644-1] [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: 02/23/2023] [Accepted: 07/31/2023] [Indexed: 08/12/2023] Open
Abstract
BACKGROUND Mutations of the gene TMEM106B are risk factors for diverse neurodegenerative diseases. Previous understanding of the underlying mechanism focused on the impairment of lysosome biogenesis caused by TMEM106B loss-of-function. However, mutations in TMEM106B increase its expression level, thus the molecular process linking these mutations to the apparent disruption in TMEM106B function remains mysterious. MAIN BODY Recent new studies reported that TMEM106B proteins form intracellular amyloid filaments which universally exist in various neurodegenerative diseases, sometimes being the dominant form of protein aggregation. In light of these new findings, in this review we systematically examined previous efforts in understanding the function of TMEM106B in physiological and pathological conditions. We propose that TMEM106B aggregations could recruit normal TMEM106B proteins and interfere with their function. CONCLUSIONS TMEM106B mutations could lead to lysosome dysfunction by promoting the aggregation of TMEM106B and reducing these aggregations may restore lysosomal function, providing a potential therapeutic target for various neurodegenerative diseases.
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Affiliation(s)
- Hai-Shan Jiao
- Department of Neurology and National Center for Neurological Disorders, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200040, China
| | - Peng Yuan
- Department of Rehabilitation Medicine, State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Huashan Hospital, Institute for Translational Brain Research, Fudan University, Shanghai, China.
| | - Jin-Tai Yu
- Department of Neurology and National Center for Neurological Disorders, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, 200040, China.
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11
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Feng T, Minevich G, Liu P, Qin HX, Wozniak G, Pham J, Pham K, Korgaonkar A, Kurnellas M, Defranoux NA, Long H, Mitra A, Hu F. AAV- GRN partially corrects motor deficits and ALS/FTLD-related pathology in Tmem106b-/-Grn-/- mice. iScience 2023; 26:107247. [PMID: 37519899 PMCID: PMC10371829 DOI: 10.1016/j.isci.2023.107247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/18/2023] [Accepted: 06/26/2023] [Indexed: 08/01/2023] Open
Abstract
Loss of function of progranulin (PGRN), encoded by the granulin (GRN) gene, is implicated in several neurodegenerative diseases. Several therapeutics to boost PGRN levels are currently in clinical trials. However, it is difficult to test the efficacy of PGRN-enhancing drugs in mouse models due to the mild phenotypes of Grn-/- mice. Recently, mice deficient in both PGRN and TMEM106B were shown to develop severe motor deficits and pathology. Here, we show that intracerebral ventricle injection of PGRN-expressing AAV1/9 viruses partially rescues motor deficits, neuronal loss, glial activation, and lysosomal abnormalities in Tmem106b-/-Grn-/- mice. Widespread expression of PGRN is detected in both the brain and spinal cord for both AAV subtypes. However, AAV9 but not AAV1-mediated expression of PGRN results in high levels of PGRN in the serum. Together, these data support using the Tmem106b-/-Grn-/- mouse strain as a robust mouse model to determine the efficacy of PGRN-elevating therapeutics.
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Affiliation(s)
- Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | | | - Pengan Liu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Henry Xin Qin
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | | | - Jenny Pham
- Alector Inc, South San Francisco, CA 94080, USA
| | - Khanh Pham
- Alector Inc, South San Francisco, CA 94080, USA
| | | | | | | | - Hua Long
- Alector Inc, South San Francisco, CA 94080, USA
| | | | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
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12
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Zhang T, Feng T, Wu K, Guo J, Nana AL, Yang G, Seeley WW, Hu F. Progranulin deficiency results in sex-dependent alterations in microglia in response to demyelination. Acta Neuropathol 2023:10.1007/s00401-023-02578-w. [PMID: 37120788 PMCID: PMC10375542 DOI: 10.1007/s00401-023-02578-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 05/01/2023]
Abstract
Heterozygous mutations in the granulin (GRN) gene, resulting in the haploinsufficiency of the progranulin (PGRN) protein, is a leading cause of frontotemporal lobar degeneration (FTLD). Complete loss of the PGRN protein causes neuronal ceroid lipofuscinosis (NCL), a lysosomal storage disorder. Polymorphisms in the GRN gene have also been associated with several other neurodegenerative diseases, including Alzheimer's disease (AD), and Parkinson's disease (PD). PGRN deficiency has been shown to cause myelination defects previously, but how PGRN regulates myelination is unknown. Here, we report that PGRN deficiency leads to a sex-dependent myelination defect with male mice showing more severe demyelination in response to cuprizone treatment. This is accompanied by exacerbated microglial proliferation and activation in the male PGRN-deficient mice. Interestingly, both male and female PGRN-deficient mice show sustained microglial activation after cuprizone removal and a defect in remyelination. Specific ablation of PGRN in microglia results in similar sex-dependent phenotypes, confirming a microglial function of PGRN. Lipid droplets accumulate in microglia specifically in male PGRN-deficient mice. RNA-seq analysis and mitochondrial function assays reveal key differences in oxidative phosphorylation in male versus female microglia under PGRN deficiency. A significant decrease in myelination and accumulation of myelin debris and lipid droplets in microglia were found in the corpus callosum regions of FTLD patients with GRN mutations. Taken together, our data support that PGRN deficiency leads to sex-dependent alterations in microglia with subsequent myelination defects.
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Affiliation(s)
- Tingting Zhang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Kenton Wu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Jennifer Guo
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA
| | - Alissa L Nana
- Department of Neurology, University of California, San Francisco, CA, 94158, USA
| | - Guang Yang
- Department of Anesthesiology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - William W Seeley
- Department of Neurology, University of California, San Francisco, CA, 94158, USA
- Department of Pathology, University of California, San Francisco, CA, 94158, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY, 14853, USA.
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13
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Heikkinen S, Huber N, Katisko K, Kokkola T, Hartikainen P, Krüger J, Leinonen V, Korhonen VE, Herukka SK, Remes AM, Borroni B, Alberici A, Libri I, Solje E, Haapasalo A. Serum Cathepsin S Levels Do Not Show Alterations in Different Clinical, Neuropathological, or Genetic Subtypes of Frontotemporal Dementia Patients nor in Comparison to Healthy Control Individuals. J Alzheimers Dis 2023; 93:395-401. [PMID: 37038815 DOI: 10.3233/jad-221060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Frontotemporal dementia (FTD) can manifest as diverse clinical phenotypes and is frequently caused by mutations in different genes, complicating differential diagnosis. This underlines the urgent need for valid biomarkers. Altered lysosomal and immune functions proposedly contribute to FTD pathogenesis. Cathepsins, including cathepsin S, are enzymes preferentially expressed in brain in microglia, which influence lysosomal and immune function. Here, we examined whether alterations in serum cathepsin S levels associate with specific clinical, genetic, or neuropathological FTD subgroups, but no such alterations were observed. However, further research on other lysosomal proteins may reveal new biologically relevant biomarkers in FTD.
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Affiliation(s)
- Sami Heikkinen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland, Kuopio, Finland
| | - Nadine Huber
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Kasper Katisko
- Institute of Clinical Medicine – Neurology, University of Eastern Finland, Kuopio, Finland
| | - Tarja Kokkola
- Institute of Clinical Medicine – Neurology, University of Eastern Finland, Kuopio, Finland
| | - Päivi Hartikainen
- Neuro Center, Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Johanna Krüger
- Research Unit of Clinical Neuroscience, Neurology, University of Oulu, Oulu, Finland
- Neurocenter, Neurology, Oulu University Hospital, Oulu, Finland
- Medical Research Center, Oulu University Hospital, Oulu, Finland
| | - Ville Leinonen
- Neuro Center, Neurosurgery, Kuopio University Hospital, Kuopio, Finland
- Institute of Clinical Medicine –Neurosurgery, University of Eastern Finland, Kuopio, Finland
| | - Ville E. Korhonen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland, Kuopio, Finland
| | - Sanna-Kaisa Herukka
- Institute of Clinical Medicine – Neurology, University of Eastern Finland, Kuopio, Finland
- Neuro Center, Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Anne M. Remes
- Research Unit of Clinical Neuroscience, Neurology, University of Oulu, Oulu, Finland
- Clinical Neurosciences, University of Helsinki, Helsinki, Finland
| | - Barbara Borroni
- Department of Neurological Sciences, University of Brescia, Brescia, Italy
| | - Antonella Alberici
- Department of Neurological Sciences, University of Brescia, Brescia, Italy
| | - Ilenia Libri
- Department of Neurological Sciences, University of Brescia, Brescia, Italy
| | - Eino Solje
- Institute of Clinical Medicine – Neurology, University of Eastern Finland, Kuopio, Finland
- Neuro Center, Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Annakaisa Haapasalo
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
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14
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Simon MJ, Logan T, DeVos SL, Di Paolo G. Lysosomal functions of progranulin and implications for treatment of frontotemporal dementia. Trends Cell Biol 2023; 33:324-339. [PMID: 36244875 DOI: 10.1016/j.tcb.2022.09.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 09/15/2022] [Accepted: 09/15/2022] [Indexed: 12/12/2022]
Abstract
Loss-of-function heterozygous mutations in GRN, the gene encoding progranulin (PGRN), were identified in patients with frontotemporal lobar degeneration (FTLD) almost two decades ago and are generally linked to reduced PGRN protein expression levels. Although initial characterization of PGRN function primarily focused on its role in extracellular signaling as a secreted protein, more recent studies revealed critical roles of PGRN in regulating lysosome function, including proteolysis and lipid degradation, consistent with its lysosomal localization. Emerging from these studies is the notion that PGRN regulates glucocerebrosidase activity via direct chaperone activities and via interaction with prosaposin (i.e., a key regulator of lysosomal sphingolipid-metabolizing enzymes), as well as with the anionic phospholipid bis(monoacylglycero)phosphate. This emerging lysosomal biology of PGRN identified novel and promising opportunities in therapeutic discovery as well as biomarker development.
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Affiliation(s)
| | - Todd Logan
- Denali Therapeutics, South San Francisco, CA, USA
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15
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Hasan S, Fernandopulle MS, Humble SW, Frankenfield AM, Li H, Prestil R, Johnson KR, Ryan BJ, Wade-Martins R, Ward ME, Hao L. Multi-modal Proteomic Characterization of Lysosomal Function and Proteostasis in Progranulin-Deficient Neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.24.529955. [PMID: 36865171 PMCID: PMC9980118 DOI: 10.1101/2023.02.24.529955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Progranulin (PGRN) is a lysosomal protein implicated in various neurodegenerative diseases. Over 70 mutations discovered in the GRN gene all result in reduced expression of PGRN protein. However, the detailed molecular function of PGRN within lysosomes and the impact of PGRN deficiency on lysosomal biology remain unclear. Here we leveraged multifaceted proteomic techniques to comprehensively characterize how PGRN deficiency changes the molecular and functional landscape of neuronal lysosomes. Using lysosome proximity labeling and immuno-purification of intact lysosomes, we characterized lysosome compositions and interactomes in both human induced pluripotent stem cell (iPSC)-derived glutamatergic neurons (i3Neurons) and mouse brains. Using dynamic stable isotope labeling by amino acids in cell culture (dSILAC) proteomics, we measured global protein half-lives in i3Neurons for the first time and characterized the impact of progranulin deficiency on neuronal proteostasis. Together, this study indicated that PGRN loss impairs the lysosome's degradative capacity with increased levels of v-ATPase subunits on the lysosome membrane, increased catabolic enzymes within the lysosome, elevated lysosomal pH, and pronounced alterations in neuron protein turnover. Collectively, these results suggested PGRN as a critical regulator of lysosomal pH and degradative capacity, which in turn influences global proteostasis in neurons. The multi-modal techniques developed here also provided useful data resources and tools to study the highly dynamic lysosome biology in neurons.
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Affiliation(s)
- Saadia Hasan
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- UK Dementia Research Institute, Department of Neurodegenerative Disease, Institute of Neurology, University College London, London, UK
- MD-PhD program, Augusta University/University of Georgia Medical Partnership, Athens, GA, USA
| | - Michael S. Fernandopulle
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
- Medical Scientist Training Program, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Stewart W. Humble
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
- Oxford Parkinson’s Disease Centre, Kavli Institute for Nanoscience Discovery, Department of Physiology, Anatomy and Genetics, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | | | - Haorong Li
- Department of Chemistry, George Washington University, Washington, DC, USA
| | - Ryan Prestil
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
| | - Kory R. Johnson
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Brent J. Ryan
- Oxford Parkinson’s Disease Centre, Kavli Institute for Nanoscience Discovery, Department of Physiology, Anatomy and Genetics, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | - Richard Wade-Martins
- Oxford Parkinson’s Disease Centre, Kavli Institute for Nanoscience Discovery, Department of Physiology, Anatomy and Genetics, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Road, Oxford, OX1 3QU UK
| | - Michael E. Ward
- National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Ling Hao
- Department of Chemistry, George Washington University, Washington, DC, USA
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16
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Tran ML, Tüshaus J, Kim Y, Ramazanov BR, Devireddy S, Lichtenthaler SF, Ferguson SM, von Blume J. Cab45 deficiency leads to the mistargeting of progranulin and prosaposin and aberrant lysosomal positioning. Traffic 2023; 24:4-19. [PMID: 36398980 PMCID: PMC9825660 DOI: 10.1111/tra.12873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 10/23/2022] [Accepted: 11/09/2022] [Indexed: 11/21/2022]
Abstract
The trans-Golgi Network (TGN) sorts molecular "addresses" and sends newly synthesized proteins to their destination via vesicular transport carriers. Despite the functional significance of packaging processes at the TGN, the sorting of soluble proteins remains poorly understood. Recent research has shown that the Golgi resident protein Cab45 is a significant regulator of secretory cargo sorting at the TGN. Cab45 oligomerizes upon transient Ca2+ influx, recruits soluble cargo molecules (clients), and packs them in sphingomyelin-rich transport carriers. However, the identity of client molecules packed into Cab45 vesicles is scarce. Therefore, we used a precise and highly efficient secretome analysis technology called hiSPECs. Intriguingly, we observed that Cab45 deficient cells manifest hypersecretion of lysosomal hydrolases. Specifically, Cab45 deficient cells secrete the unprocessed precursors of prosaposin (PSAP) and progranulin (PGRN). In addition, lysosomes in these cells show an aberrant perinuclear accumulation suggesting a new role of Cab45 in lysosomal positioning. This work uncovers a yet unknown function of Cab45 in regulating lysosomal function.
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Affiliation(s)
- Mai Ly Tran
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Johanna Tüshaus
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
- Neuroproteomics, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, 81675
| | - Yeongho Kim
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Bulat R. Ramazanov
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Swathi Devireddy
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA
- Wu Tsai Institute, Yale University, New Haven, CT, USA
| | - Stefan F. Lichtenthaler
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
- Neuroproteomics, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, 81675
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Shawn M. Ferguson
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA
- Wu Tsai Institute, Yale University, New Haven, CT, USA
| | - Julia von Blume
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
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17
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Bossolasco P, Cimini S, Maderna E, Bardelli D, Canafoglia L, Cavallaro T, Ricci M, Silani V, Marucci G, Rossi G. GRN−/− iPSC-derived cortical neurons recapitulate the pathological findings of both frontotemporal lobar degeneration and neuronal ceroidolipofuscinosis. Neurobiol Dis 2022; 175:105891. [DOI: 10.1016/j.nbd.2022.105891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 09/27/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022] Open
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18
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Santos MN, Paushter DH, Zhang T, Wu X, Feng T, Lou J, Du H, Becker SM, Fragoza R, Yu H, Hu F. Progranulin-derived granulin E and lysosome membrane protein CD68 interact to reciprocally regulate their protein homeostasis. J Biol Chem 2022; 298:102348. [PMID: 35933009 PMCID: PMC9450144 DOI: 10.1016/j.jbc.2022.102348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 11/17/2022] Open
Abstract
Progranulin (PGRN) is a glycoprotein implicated in several neurodegenerative diseases. It is highly expressed in microglia and macrophages and can be secreted or delivered to the lysosome compartment. PGRN comprises 7.5 granulin repeats and is processed into individual granulin peptides within the lysosome, but the functions of these peptides are largely unknown. Here, we identify CD68, a lysosome membrane protein mainly expressed in hematopoietic cells, as a binding partner of PGRN and PGRN-derived granulin E. Deletion analysis of CD68 showed that this interaction is mediated by the mucin–proline-rich domain of CD68. While CD68 deficiency does not affect the lysosomal localization of PGRN, it results in a specific decrease in the levels of granulin E but no other granulin peptides. On the other hand, the deficiency of PGRN, and its derivative granulin peptides, leads to a significant shift in the molecular weight of CD68, without altering CD68 localization within the cell. Our results support that granulin E and CD68 reciprocally regulate each other’s protein homeostasis.
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Affiliation(s)
- Mariela Nunez Santos
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Daniel H Paushter
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Tingting Zhang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Xiaochun Wu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Jiaoying Lou
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA; Department of Gynecology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing, P. R. China
| | - Huan Du
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Stephanie M Becker
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Robert Fragoza
- Department of Computational Biology, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Haiyuan Yu
- Department of Computational Biology, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, USA.
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19
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Kim WD, Wilson-Smillie MLDM, Thanabalasingam A, Lefrancois S, Cotman SL, Huber RJ. Autophagy in the Neuronal Ceroid Lipofuscinoses (Batten Disease). Front Cell Dev Biol 2022; 10:812728. [PMID: 35252181 PMCID: PMC8888908 DOI: 10.3389/fcell.2022.812728] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/24/2022] [Indexed: 12/22/2022] Open
Abstract
The neuronal ceroid lipofuscinoses (NCLs), also referred to as Batten disease, are a family of neurodegenerative diseases that affect all age groups and ethnicities around the globe. At least a dozen NCL subtypes have been identified that are each linked to a mutation in a distinct ceroid lipofuscinosis neuronal (CLN) gene. Mutations in CLN genes cause the accumulation of autofluorescent lipoprotein aggregates, called ceroid lipofuscin, in neurons and other cell types outside the central nervous system. The mechanisms regulating the accumulation of this material are not entirely known. The CLN genes encode cytosolic, lysosomal, and integral membrane proteins that are associated with a variety of cellular processes, and accumulated evidence suggests they participate in shared or convergent biological pathways. Research across a variety of non-mammalian and mammalian model systems clearly supports an effect of CLN gene mutations on autophagy, suggesting that autophagy plays an essential role in the development and progression of the NCLs. In this review, we summarize research linking the autophagy pathway to the NCLs to guide future work that further elucidates the contribution of altered autophagy to NCL pathology.
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Affiliation(s)
- William D. Kim
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada
| | | | - Aruban Thanabalasingam
- Environmental and Life Sciences Graduate Program, Trent University, Peterborough, ON, Canada
| | - Stephane Lefrancois
- Centre Armand-Frappier Santé Biotechnologie, Institut National de La Recherche Scientifique, Laval, QC, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
- Centre D'Excellence en Recherche sur Les Maladies Orphelines–Fondation Courtois (CERMO-FC), Université Du Québec à Montréal (UQAM), Montréal, QC, Canada
| | - Susan L. Cotman
- Department of Neurology, Center for Genomic Medicine, Massachusetts General Hospital Research Institute, Harvard Medical School, Boston, MA, United States
| | - Robert J. Huber
- Department of Biology, Trent University, Peterborough, ON, Canada
- *Correspondence: Robert J. Huber,
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20
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Devireddy S, Ferguson SM. Efficient progranulin exit from the ER requires its interaction with prosaposin, a Surf4 cargo. J Cell Biol 2022; 221:212919. [PMID: 34919127 PMCID: PMC8689666 DOI: 10.1083/jcb.202104044] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 10/11/2021] [Accepted: 11/15/2021] [Indexed: 11/22/2022] Open
Abstract
Progranulin is a lysosomal protein whose haploinsufficiency causes frontotemporal dementia, while homozygous loss of progranulin causes neuronal ceroid lipofuscinosis, a lysosomal storage disease. The sensitivity of cells to progranulin deficiency raises important questions about how cells coordinate intracellular trafficking of progranulin to ensure its efficient delivery to lysosomes. In this study, we discover that progranulin interactions with prosaposin, another lysosomal protein, first occur within the lumen of the endoplasmic reticulum (ER) and are required for the efficient ER exit of progranulin. Mechanistically, we identify an interaction between prosaposin and Surf4, a receptor that promotes loading of lumenal cargos into COPII-coated vesicles, and establish that Surf4 is critical for the efficient export of progranulin and prosaposin from the ER. Collectively, this work demonstrates that a network of interactions occurring early in the secretory pathway promote the ER exit and subsequent lysosomal delivery of newly translated progranulin and prosaposin.
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Affiliation(s)
- Swathi Devireddy
- Departments of Cell Biology and Neuroscience, Program in Cellular Neuroscience, Neurodegeneration and Repair, Wu Tsai Institute, Yale University School of Medicine, New Haven, CT
| | - Shawn M Ferguson
- Departments of Cell Biology and Neuroscience, Program in Cellular Neuroscience, Neurodegeneration and Repair, Wu Tsai Institute, Yale University School of Medicine, New Haven, CT
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21
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Zhang T, Du H, Santos MN, Wu X, Pagan MD, Trigiani LJ, Nishimura N, Reinheckel T, Hu F. Differential regulation of progranulin derived granulin peptides. Mol Neurodegener 2022; 17:15. [PMID: 35120524 PMCID: PMC8815130 DOI: 10.1186/s13024-021-00513-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 12/22/2021] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Haploinsufficiency of progranulin (PGRN) is a leading cause of frontotemporal lobar degeneration (FTLD). PGRN is comprised of 7.5 granulin repeats and is processed into individual granulin peptides in the lysosome. However, very little is known about the levels and regulations of individual granulin peptides due to the lack of specific antibodies. RESULTS Here we report the generation and characterization of antibodies specific to each granulin peptide. We found that the levels of granulins C, E and F are regulated differently compared to granulins A and B in various tissues. The levels of PGRN and granulin peptides vary in different brain regions and the ratio between granulins and PGRN is highest in the cortical region in the adult male mouse brain. Granulin-A is localized in the lysosome in both neurons and microglia and its levels in microglia increase under pathological conditions. Interestingly, the levels of granulin A in microglia change correspondingly with PGRN in response to stroke but not demyelination. Furthermore, deficiency of lysosomal proteases and the PGRN binding partner prosaposin leads to alterations in the ratios between individual granulin peptides. Granulins B, C and E are heavily glycosylated and the glycosylation patterns can be regulated. CONCLUSION Our results support that the levels of individual granulin peptides are differentially regulated under physiological and pathological conditions and provide novel insights into how granulin peptides function in the lysosome.
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Affiliation(s)
- Tingting Zhang
- grid.5386.8000000041936877XDepartment of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY 14853 USA
| | - Huan Du
- grid.5386.8000000041936877XDepartment of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY 14853 USA
| | - Mariela Nunez Santos
- grid.5386.8000000041936877XDepartment of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY 14853 USA
| | - Xiaochun Wu
- grid.5386.8000000041936877XDepartment of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY 14853 USA
| | - Mitchell D. Pagan
- grid.5386.8000000041936877XDepartment of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY 14853 USA
| | - Lianne Jillian Trigiani
- grid.5386.8000000041936877XNancy E. and Peter C. Meining School of Biomedical Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Nozomi Nishimura
- grid.5386.8000000041936877XNancy E. and Peter C. Meining School of Biomedical Engineering, Cornell University, Ithaca, NY 14853 USA
| | - Thomas Reinheckel
- grid.5963.9Institute of Molecular Medicine and Cell Research, Medical Faculty and BIOSS Centre for Biological Signaling Studies, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Fenghua Hu
- grid.5386.8000000041936877XDepartment of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, 345 Weill Hall, Ithaca, NY 14853 USA
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22
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Du H, Zhou X, Feng T, Hu F. Regulation of lysosomal trafficking of progranulin by sortilin and prosaposin. Brain Commun 2022; 4:fcab310. [PMID: 35169707 PMCID: PMC8833632 DOI: 10.1093/braincomms/fcab310] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/19/2021] [Accepted: 12/13/2021] [Indexed: 01/07/2023] Open
Abstract
Haploinsufficiency of the progranulin protein is a leading cause of frontotemporal lobar degeneration. Accumulating evidence support a crucial role of progranulin in the lysosome. Progranulin comprises 7.5 granulin repeats and is known to traffic to lysosomes via direct interactions with prosaposin or sortilin. Within the lysosome, progranulin gets processed into granulin peptides. Here, we report that sortilin and prosaposin independently regulate lysosomal trafficking of progranulin in vivo. The deletion of either prosaposin or sortilin alone results in a significant decrease in the ratio of granulin peptides versus full-length progranulin in mouse brain lysates. This decrease is further augmented by the deficiency of both prosaposin and sortilin. A concomitant increase in the levels of secreted progranulin in the serum was observed. Interestingly, while the deletion of both prosaposin and sortilin totally abolishes lysosomal localization of progranulin in neurons, it has a limited effect on lysosomal trafficking of progranulin in microglia, suggesting the existence of a novel sortilin and prosaposin independent pathway mediating progranulin lysosomal trafficking. In summary, our studies shed light on the regulation of lysosomal trafficking and processing of progranulin in vivo.
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Affiliation(s)
- Huan Du
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Xiaolai Zhou
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA,State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Fenghua Hu
- Correspondence to: Fenghua Hu 345 Weill Hall, Ithaca NY 14853, USA E-mail:
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23
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Petese A, Cesaroni V, Cerri S, Blandini F. Are Lysosomes Potential Therapeutic Targets for Parkinson's Disease? CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2022; 21:642-655. [PMID: 34370650 DOI: 10.2174/1871527320666210809123630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 05/16/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
Parkinson´s Disease (PD) is the second most common neurodegenerative disorder, affecting ~2-3% of the population over 65 years old. In addition to progressive degeneration of nigrostriatal neurons, the histopathological feature of PD is the accumulation of misfolded α-synuclein protein in abnormal cytoplasmatic inclusions, known as Lewy Bodies (LBs). Recently, Genome-Wide Association Studies (GWAS) have indicated a clear association of variants within several lysosomal genes with risk for PD. Newly evolving data have been shedding light on the relationship between lysosomal dysfunction and alpha-synuclein aggregation. Defects in lysosomal enzymes could lead to the insufficient clearance of neurotoxic protein materials, possibly leading to selective degeneration of dopaminergic neurons. Specific modulation of lysosomal pathways and their components could be considered a novel opportunity for therapeutic intervention for PD. The purpose of this review is to illustrate lysosomal biology and describe the role of lysosomal dysfunction in PD pathogenesis. Finally, the most promising novel therapeutic approaches designed to modulate lysosomal activity, as a potential disease-modifying treatment for PD will be highlighted.
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Affiliation(s)
- Alessandro Petese
- Cellular and Molecular Neurobiology Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Valentina Cesaroni
- Cellular and Molecular Neurobiology Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Silvia Cerri
- Cellular and Molecular Neurobiology Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Fabio Blandini
- Cellular and Molecular Neurobiology Unit, IRCCS Mondino Foundation, Pavia, Italy
- Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy
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24
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Li R, Chen W, Lu C, Li X, Chen X, Huang G, Wen Z, Li H, Tao L, Hu Y, Zhao Z, Chen Z, Ni L, Lai Y. A four-microRNA panel in serum may serve as potential biomarker for renal cell carcinoma diagnosis. Front Oncol 2022; 12:1076303. [PMID: 36727070 PMCID: PMC9885090 DOI: 10.3389/fonc.2022.1076303] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 12/22/2022] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Renal cell carcinoma (RCC) is one out of the most universal malignant tumors globally, and its incidence is increasing annually. MicroRNA (miRNA) in serum could be considered as a non-invasive detecting biomarker for RCC diagnosis. METHOD A total of 224 participants (112 RCC patients (RCCs) and 112 normal controls (NCs)) were enrolled in the three-phrase study. Reverse transcription quantitative PCR (RT-qPCR) was applied to reveal the miRNA expression levels in RCCs and NCs. Receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC) were utilized to predict the diagnostic ability of serum miRNAs for RCC. Bioinformatic analysis and survival analysis were also included in our study. RESULTS Compared to NCs, the expression degree of miR-155-5p, miR-224-5p in serum was significantly upregulated in RCC patients, and miR-1-3p, miR-124-3p, miR-129-5p, and miR-200b-3p were downregulated. A four-miRNA panel was construed, and the AUC of the panel was 0.903 (95% CI: 0.847-0.944; p < 0.001; sensitivity = 75.61%, specificity = 93.67%). Results from GEPIA database indicated that CHL1, MPP5, and SORT1 could be seen as promising target genes of the four-miRNA panel. Survival analysis of candidate miRNAs manifested that miR-155-5p was associated with the survival rate of RCC significantly. CONCLUSIONS The four-miRNA panel in serum has a great potential to be non-invasive biomarkers for RCC sift to check.
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Affiliation(s)
- Rongkang Li
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- The Fifth Clinical Medical College of Anhui Medical University, Hefei, Anhui, China
| | - Wenkang Chen
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- Shantou University Medical College, Shantou, Guangdong, China
| | - Chong Lu
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- The Fifth Clinical Medical College of Anhui Medical University, Hefei, Anhui, China
| | - Xinji Li
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- Shantou University Medical College, Shantou, Guangdong, China
| | - Xuan Chen
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- Shantou University Medical College, Shantou, Guangdong, China
| | - Guocheng Huang
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- Shantou University Medical College, Shantou, Guangdong, China
| | - Zhenyu Wen
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- Shantou University Medical College, Shantou, Guangdong, China
| | - Hang Li
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
| | - Lingzhi Tao
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
| | - Yimin Hu
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
| | - Zhengping Zhao
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
| | - Zebo Chen
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
| | - Liangchao Ni
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- Shantou University Medical College, Shantou, Guangdong, China
- *Correspondence: Yongqing Lai, ; Liangchao Ni,
| | - Yongqing Lai
- Department of Urology, Guangdong and Shenzhen Key Laboratory of Reproductive Medicine and Genetics, Peking University Shenzhen Hospital, Clinical College of Anhui Medical University, Shenzhen, Guangdong, China
- The Fifth Clinical Medical College of Anhui Medical University, Hefei, Anhui, China
- *Correspondence: Yongqing Lai, ; Liangchao Ni,
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25
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Dong T, Tejwani L, Jung Y, Kokubu H, Luttik K, Driessen TM, Lim J. Microglia regulate brain progranulin levels through the endocytosis/lysosomal pathway. JCI Insight 2021; 6:e136147. [PMID: 34618685 PMCID: PMC8663778 DOI: 10.1172/jci.insight.136147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 10/06/2021] [Indexed: 01/01/2023] Open
Abstract
Genetic variants in Granulin (GRN), which encodes the secreted glycoprotein progranulin (PGRN), are associated with several neurodegenerative diseases, including frontotemporal lobar degeneration, neuronal ceroid lipofuscinosis, and Alzheimer's disease. These genetic alterations manifest in pathological changes due to a reduction of PGRN expression; therefore, identifying factors that can modulate PGRN levels in vivo would enhance our understanding of PGRN in neurodegeneration and could reveal novel potential therapeutic targets. Here, we report that modulation of the endocytosis/lysosomal pathway via reduction of Nemo-like kinase (Nlk) in microglia, but not in neurons, can alter total brain Pgrn levels in mice. We demonstrate that Nlk reduction promotes Pgrn degradation by enhancing its trafficking through the endocytosis/lysosomal pathway, specifically in microglia. Furthermore, genetic interaction studies in mice showed that Nlk heterozygosity in Grn haploinsufficient mice further reduces Pgrn levels and induces neuropathological phenotypes associated with PGRN deficiency. Our results reveal a mechanism for Pgrn level regulation in the brain through the active catabolism by microglia and provide insights into the pathophysiology of PGRN-associated diseases.
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Affiliation(s)
- Tingting Dong
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Leon Tejwani
- Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut, USA
- Department of Neuroscience
| | - Youngseob Jung
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Hiroshi Kokubu
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Kimberly Luttik
- Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut, USA
- Department of Neuroscience
| | - Terri M. Driessen
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
| | - Janghoo Lim
- Department of Genetics, Yale School of Medicine, New Haven, Connecticut, USA
- Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut, USA
- Department of Neuroscience
- Program in Cellular Neuroscience, Neurodegeneration and Repair, and
- Yale Stem Cell Center, Yale School of Medicine, New Haven, Connecticut, USA
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26
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Logan T, Simon MJ, Rana A, Cherf GM, Srivastava A, Davis SS, Low RLY, Chiu CL, Fang M, Huang F, Bhalla A, Llapashtica C, Prorok R, Pizzo ME, Calvert MEK, Sun EW, Hsiao-Nakamoto J, Rajendra Y, Lexa KW, Srivastava DB, van Lengerich B, Wang J, Robles-Colmenares Y, Kim DJ, Duque J, Lenser M, Earr TK, Nguyen H, Chau R, Tsogtbaatar B, Ravi R, Skuja LL, Solanoy H, Rosen HJ, Boeve BF, Boxer AL, Heuer HW, Dennis MS, Kariolis MS, Monroe KM, Przybyla L, Sanchez PE, Meisner R, Diaz D, Henne KR, Watts RJ, Henry AG, Gunasekaran K, Astarita G, Suh JH, Lewcock JW, DeVos SL, Di Paolo G. Rescue of a lysosomal storage disorder caused by Grn loss of function with a brain penetrant progranulin biologic. Cell 2021; 184:4651-4668.e25. [PMID: 34450028 PMCID: PMC8489356 DOI: 10.1016/j.cell.2021.08.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 05/11/2021] [Accepted: 08/02/2021] [Indexed: 12/26/2022]
Abstract
GRN mutations cause frontotemporal dementia (GRN-FTD) due to deficiency in progranulin (PGRN), a lysosomal and secreted protein with unclear function. Here, we found that Grn-/- mice exhibit a global deficiency in bis(monoacylglycero)phosphate (BMP), an endolysosomal phospholipid we identified as a pH-dependent PGRN interactor as well as a redox-sensitive enhancer of lysosomal proteolysis and lipolysis. Grn-/- brains also showed an age-dependent, secondary storage of glucocerebrosidase substrate glucosylsphingosine. We investigated a protein replacement strategy by engineering protein transport vehicle (PTV):PGRN-a recombinant protein linking PGRN to a modified Fc domain that binds human transferrin receptor for enhanced CNS biodistribution. PTV:PGRN rescued various Grn-/- phenotypes in primary murine macrophages and human iPSC-derived microglia, including oxidative stress, lysosomal dysfunction, and endomembrane damage. Peripherally delivered PTV:PGRN corrected levels of BMP, glucosylsphingosine, and disease pathology in Grn-/- CNS, including microgliosis, lipofuscinosis, and neuronal damage. PTV:PGRN thus represents a potential biotherapeutic for GRN-FTD.
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Affiliation(s)
- Todd Logan
- Denali Therapeutics, South San Francisco, CA, USA
| | | | - Anil Rana
- Denali Therapeutics, South San Francisco, CA, USA
| | | | | | | | | | - Chi-Lu Chiu
- Denali Therapeutics, South San Francisco, CA, USA
| | - Meng Fang
- Denali Therapeutics, South San Francisco, CA, USA
| | - Fen Huang
- Denali Therapeutics, South San Francisco, CA, USA
| | - Akhil Bhalla
- Denali Therapeutics, South San Francisco, CA, USA
| | | | | | | | | | | | | | | | | | | | | | - Junhua Wang
- Denali Therapeutics, South San Francisco, CA, USA
| | | | - Do Jin Kim
- Denali Therapeutics, South San Francisco, CA, USA
| | - Joseph Duque
- Denali Therapeutics, South San Francisco, CA, USA
| | | | | | - Hoang Nguyen
- Denali Therapeutics, South San Francisco, CA, USA
| | - Roni Chau
- Denali Therapeutics, South San Francisco, CA, USA
| | | | - Ritesh Ravi
- Denali Therapeutics, South San Francisco, CA, USA
| | | | | | - Howard J Rosen
- Memory and Aging Center, Department of Neurology, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; On behalf of the ALLFTD investigators
| | - Bradley F Boeve
- On behalf of the ALLFTD investigators; Department of Neurology, College of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Adam L Boxer
- Memory and Aging Center, Department of Neurology, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; On behalf of the ALLFTD investigators
| | - Hilary W Heuer
- Memory and Aging Center, Department of Neurology, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA; On behalf of the ALLFTD investigators
| | | | | | | | | | | | - Rene Meisner
- Denali Therapeutics, South San Francisco, CA, USA
| | - Dolores Diaz
- Denali Therapeutics, South San Francisco, CA, USA
| | - Kirk R Henne
- Denali Therapeutics, South San Francisco, CA, USA
| | - Ryan J Watts
- Denali Therapeutics, South San Francisco, CA, USA
| | | | | | - Giuseppe Astarita
- Denali Therapeutics, South San Francisco, CA, USA; Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, DC, USA
| | - Jung H Suh
- Denali Therapeutics, South San Francisco, CA, USA
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Wu Y, Shao W, Todd TW, Tong J, Yue M, Koga S, Castanedes-Casey M, Librero AL, Lee CW, Mackenzie IR, Dickson DW, Zhang YJ, Petrucelli L, Prudencio M. Microglial lysosome dysfunction contributes to white matter pathology and TDP-43 proteinopathy in GRN-associated FTD. Cell Rep 2021; 36:109581. [PMID: 34433069 PMCID: PMC8491969 DOI: 10.1016/j.celrep.2021.109581] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 06/07/2021] [Accepted: 07/29/2021] [Indexed: 11/04/2022] Open
Abstract
Loss-of-function mutations in the progranulin gene (GRN), which encodes progranulin (PGRN), are a major cause of frontotemporal dementia (FTD). GRN-associated FTD is characterized by TDP-43 inclusions and neuroinflammation, but how PGRN loss causes disease remains elusive. We show that Grn knockout (KO) mice have increased microgliosis in white matter and an accumulation of myelin debris in microglial lysosomes in the same regions. Accumulation of myelin debris is also observed in white matter of patients with GRN-associated FTD. In addition, our findings also suggest that PGRN insufficiency in microglia leads to impaired lysosomal-mediated clearance of myelin debris. Finally, Grn KO mice that are deficient in cathepsin D (Ctsd), a key lysosomal enzyme, have augmented myelin debris and increased neuronal TDP-43 pathology. Together, our data strongly imply that PGRN loss affects microglial activation and lysosomal function, resulting in the accumulation of myelin debris and contributing to TDP-43 pathology. Wu et al. show increased microgliosis in white matter of Grn knockout mice. Microglial lysosomes accumulate myelin debris in both Grn knockout mice and patients with GRN-associated FTD, and reducing cathespin D levels exacerbates both myelin debris accumulation and pTdp-43 aggregation. Thus, lysosomal dysfunction affects these pathologies in GRN-related FTD.
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Affiliation(s)
- Yanwei Wu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Wei Shao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Tiffany W Todd
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Jimei Tong
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Mei Yue
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Shunsuke Koga
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | | | - Ariston L Librero
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Chris W Lee
- Atlantic Health System, Morristown, NJ 07960, USA; Biomedical Research Institute of New Jersey, Cedar Knolls, NJ 07927, USA
| | - Ian R Mackenzie
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC V6T 2B5, Canada
| | - Dennis W Dickson
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA; Neurobiology of Disease Graduate Program, Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN 55902, USA
| | - Yong-Jie Zhang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA; Neurobiology of Disease Graduate Program, Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN 55902, USA
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA; Neurobiology of Disease Graduate Program, Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN 55902, USA.
| | - Mercedes Prudencio
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA; Neurobiology of Disease Graduate Program, Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN 55902, USA.
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28
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Callizot N, Estrella C, Burlet S, Henriques A, Brantis C, Barrier M, Campanari ML, Verwaerde P. AZP2006, a new promising treatment for Alzheimer's and related diseases. Sci Rep 2021; 11:16806. [PMID: 34413330 PMCID: PMC8376949 DOI: 10.1038/s41598-021-94708-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 07/08/2021] [Indexed: 02/07/2023] Open
Abstract
Progranulin (PGRN) is a protein with multiple functions including the regulation of neuroinflammation, neuronal survival, neurite and synapsis growth. Although the mechanisms of action of PGRN are currently unknown, its potential therapeutic application in treating neurodegenerative diseases is huge. Thus, strategies to increase PGRN levels in patients could provide an effective treatment. In the present study, we investigated the effects of AZP2006, a lysotropic molecule now in phase 2a clinical trial in Progressive Supranuclear Palsy patients, for its ability to increase PGRN level and promote neuroprotection. We showed for the first time the in vitro and in vivo neuroprotective effects of AZP2006 in neurons injured with Aβ1-42 and in two different pathological animal models of Alzheimer's disease (AD) and aging. Thus, the chronic treatment with AZP2006 was shown to reduce the loss of central synapses and neurons but also to dramatically decrease the massive neuroinflammation associated with the animal pathology. A deeper investigation showed that the beneficial effects of AZP2006 were associated with PGRN production. Also, AZP2006 binds to PSAP (the cofactor of PGRN) and inhibits TLR9 receptors normally responsible for proinflammation when activated. Altogether, these results showed the high potential of AZP2006 as a new putative treatment for AD and related diseases.
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Affiliation(s)
- N Callizot
- Alzprotect, Parc Eurasanté, 85C rue Nelson Mandela, 59120, Loos, France.
- Neuro-Sys, 410 Chemin Départemental 60, 13120, Gardanne, France.
| | - C Estrella
- Alzprotect, Parc Eurasanté, 85C rue Nelson Mandela, 59120, Loos, France
| | - S Burlet
- Alzprotect, Parc Eurasanté, 85C rue Nelson Mandela, 59120, Loos, France
| | - A Henriques
- Neuro-Sys, 410 Chemin Départemental 60, 13120, Gardanne, France
| | - C Brantis
- Alzprotect, Parc Eurasanté, 85C rue Nelson Mandela, 59120, Loos, France
| | - M Barrier
- Alzprotect, Parc Eurasanté, 85C rue Nelson Mandela, 59120, Loos, France
| | - M L Campanari
- Neuro-Sys, 410 Chemin Départemental 60, 13120, Gardanne, France
| | - P Verwaerde
- Alzprotect, Parc Eurasanté, 85C rue Nelson Mandela, 59120, Loos, France
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29
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Mohan S, Sampognaro PJ, Argouarch AR, Maynard JC, Welch M, Patwardhan A, Courtney EC, Zhang J, Mason A, Li KH, Huang EJ, Seeley WW, Miller BL, Burlingame A, Jacobson MP, Kao AW. Processing of progranulin into granulins involves multiple lysosomal proteases and is affected in frontotemporal lobar degeneration. Mol Neurodegener 2021; 16:51. [PMID: 34344440 PMCID: PMC8330050 DOI: 10.1186/s13024-021-00472-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 07/13/2021] [Indexed: 11/24/2022] Open
Abstract
Background Progranulin loss-of-function mutations are linked to frontotemporal lobar degeneration with TDP-43 positive inclusions (FTLD-TDP-Pgrn). Progranulin (PGRN) is an intracellular and secreted pro-protein that is proteolytically cleaved into individual granulin peptides, which are increasingly thought to contribute to FTLD-TDP-Pgrn disease pathophysiology. Intracellular PGRN is processed into granulins in the endo-lysosomal compartments. Therefore, to better understand the conversion of intracellular PGRN into granulins, we systematically tested the ability of different classes of endo-lysosomal proteases to process PGRN at a range of pH setpoints. Results In vitro cleavage assays identified multiple enzymes that can process human PGRN into multi- and single-granulin fragments in a pH-dependent manner. We confirmed the role of cathepsin B and cathepsin L in PGRN processing and showed that these and several previously unidentified lysosomal proteases (cathepsins E, G, K, S and V) are able to process PGRN in distinctive, pH-dependent manners. In addition, we have demonstrated a new role for asparagine endopeptidase (AEP) in processing PGRN, with AEP having the unique ability to liberate granulin F from the pro-protein. Brain tissue from individuals with FTLD-TDP-Pgrn showed increased PGRN processing to granulin F and increased AEP activity in degenerating brain regions but not in regions unaffected by disease. Conclusions This study demonstrates that multiple lysosomal proteases may work in concert to liberate multi-granulin fragments and granulins. It also implicates both AEP and granulin F in the neurobiology of FTLD-TDP-Pgrn. Modulating progranulin cleavage and granulin production may represent therapeutic strategies for FTLD-Pgrn and other progranulin-related diseases. Supplementary Information The online version contains supplementary material available at 10.1186/s13024-021-00472-1.
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Affiliation(s)
- Swetha Mohan
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Paul J Sampognaro
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Andrea R Argouarch
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Jason C Maynard
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, 94143, USA
| | - Mackenzie Welch
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Anand Patwardhan
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Emma C Courtney
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Jiasheng Zhang
- Department of Pathology, University of California, San Francisco, California, 94143, USA
| | - Amanda Mason
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Kathy H Li
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, 94143, USA
| | - Eric J Huang
- Department of Pathology, University of California, San Francisco, California, 94143, USA
| | - William W Seeley
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Bruce L Miller
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA
| | - Alma Burlingame
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, 94143, USA
| | - Mathew P Jacobson
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, 94143, USA
| | - Aimee W Kao
- Department of Neurology, Memory and Aging Center, University of California, San Francisco, California, 94143, USA.
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30
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Terryn J, Verfaillie CM, Van Damme P. Tweaking Progranulin Expression: Therapeutic Avenues and Opportunities. Front Mol Neurosci 2021; 14:713031. [PMID: 34366786 PMCID: PMC8343103 DOI: 10.3389/fnmol.2021.713031] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 07/07/2021] [Indexed: 01/01/2023] Open
Abstract
Frontotemporal dementia (FTD) is a neurodegenerative disease, leading to behavioral changes and language difficulties. Heterozygous loss-of-function mutations in progranulin (GRN) induce haploinsufficiency of the protein and are associated with up to one-third of all genetic FTD cases worldwide. While the loss of GRN is primarily associated with neurodegeneration, the biological functions of the secreted growth factor-like protein are more diverse, ranging from wound healing, inflammation, vasculogenesis, and metabolic regulation to tumor cell growth and metastasis. To date, no disease-modifying treatments exist for FTD, but different therapeutic approaches to boost GRN levels in the central nervous system are currently being developed (including AAV-mediated GRN gene delivery as well as anti-SORT1 antibody therapy). In this review, we provide an overview of the multifaceted regulation of GRN levels and the corresponding therapeutic avenues. We discuss the opportunities, advantages, and potential drawbacks of the diverse approaches. Additionally, we highlight the therapeutic potential of elevating GRN levels beyond patients with loss-of-function mutations in GRN.
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Affiliation(s)
- Joke Terryn
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium
| | - Catherine M Verfaillie
- Department of Development and Regeneration, Interdepartmental Stem Cell Institute, KU Leuven-University of Leuven, Leuven, Belgium
| | - Philip Van Damme
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), KU Leuven-University of Leuven, Leuven, Belgium.,Laboratory of Neurobiology, Center for Brain and Disease Research, VIB, Leuven, Belgium.,Department of Neurology, University Hospitals Leuven, Leuven, Belgium
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31
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Davis SE, Roth JR, Aljabi Q, Hakim AR, Savell KE, Day JJ, Arrant AE. Delivering progranulin to neuronal lysosomes protects against excitotoxicity. J Biol Chem 2021; 297:100993. [PMID: 34298019 PMCID: PMC8379502 DOI: 10.1016/j.jbc.2021.100993] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 07/08/2021] [Accepted: 07/19/2021] [Indexed: 01/18/2023] Open
Abstract
Loss-of-function mutations in progranulin (GRN) are a major genetic cause of frontotemporal dementia (FTD), possibly due to loss of progranulin’s neurotrophic and anti-inflammatory effects. Progranulin promotes neuronal growth and protects against excitotoxicity and other forms of injury. It is unclear if these neurotrophic effects are mediated through cellular signaling or through promotion of lysosomal function. Progranulin is a secreted proprotein that may activate neurotrophic signaling through cell-surface receptors. However, progranulin is efficiently trafficked to lysosomes and is necessary for maintaining lysosomal function. To determine which of these mechanisms mediates progranulin’s protection against excitotoxicity, we generated lentiviral vectors expressing progranulin (PGRN) or lysosome-targeted progranulin (L-PGRN). L-PGRN was generated by fusing the LAMP-1 transmembrane and cytosolic domains to the C-terminus of progranulin. L-PGRN exhibited no detectable secretion, but was delivered to lysosomes and processed into granulins. PGRN and L-PGRN protected against NMDA excitotoxicity in rat primary cortical neurons, but L-PGRN had more consistent protective effects than PGRN. L-PGRN’s protective effects were likely mediated through the autophagy-lysosomal pathway. In control neurons, an excitotoxic dose of NMDA stimulated autophagy, and inhibiting autophagy with 3-methyladenine reduced excitotoxic cell death. L-PGRN blunted the autophagic response to NMDA and occluded the protective effect of 3-methyladenine. This was not due to a general impairment of autophagy, as L-PGRN increased basal autophagy and did not alter autophagy after nutrient starvation. These data show that progranulin’s protection against excitotoxicity does not require extracellular progranulin, but is mediated through lysosomes, providing a mechanistic link between progranulin’s lysosomal and neurotrophic effects.
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Affiliation(s)
- Skylar E Davis
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama, USA; Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jonathan R Roth
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama, USA; Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Qays Aljabi
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama, USA; Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Ahmad R Hakim
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama, USA; Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Katherine E Savell
- Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jeremy J Day
- Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama, USA; Department of Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Andrew E Arrant
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, Alabama, USA; Alzheimer's Disease Center, Evelyn F. McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, Alabama, USA.
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32
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Root J, Merino P, Nuckols A, Johnson M, Kukar T. Lysosome dysfunction as a cause of neurodegenerative diseases: Lessons from frontotemporal dementia and amyotrophic lateral sclerosis. Neurobiol Dis 2021; 154:105360. [PMID: 33812000 PMCID: PMC8113138 DOI: 10.1016/j.nbd.2021.105360] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 03/16/2021] [Accepted: 03/29/2021] [Indexed: 12/11/2022] Open
Abstract
Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are fatal neurodegenerative disorders that are thought to exist on a clinical and pathological spectrum. FTD and ALS are linked by shared genetic causes (e.g. C9orf72 hexanucleotide repeat expansions) and neuropathology, such as inclusions of ubiquitinated, misfolded proteins (e.g. TAR DNA-binding protein 43; TDP-43) in the CNS. Furthermore, some genes that cause FTD or ALS when mutated encode proteins that localize to the lysosome or modulate endosome-lysosome function, including lysosomal fusion, cargo trafficking, lysosomal acidification, autophagy, or TFEB activity. In this review, we summarize evidence that lysosomal dysfunction, caused by genetic mutations (e.g. C9orf72, GRN, MAPT, TMEM106B) or toxic-gain of function (e.g. aggregation of TDP-43 or tau), is an important pathogenic disease mechanism in FTD and ALS. Further studies into the normal function of many of these proteins are required and will help uncover the mechanisms that cause lysosomal dysfunction in FTD and ALS. Mutations or polymorphisms in genes that encode proteins important for endosome-lysosome function also occur in other age-dependent neurodegenerative diseases, including Alzheimer's (e.g. APOE, PSEN1, APP) and Parkinson's (e.g. GBA, LRRK2, ATP13A2) disease. A more complete understanding of the common and unique features of lysosome dysfunction across the spectrum of neurodegeneration will help guide the development of therapies for these devastating diseases.
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Affiliation(s)
- Jessica Root
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Paola Merino
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Austin Nuckols
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Michelle Johnson
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia
| | - Thomas Kukar
- Department of Pharmacology and Chemical Biology, Emory University, School of Medicine, Atlanta 30322, Georgia; Center for Neurodegenerative Disease, Emory University, School of Medicine, Atlanta 30322, Georgia; Department of Neurology, Emory University, School of Medicine, Atlanta 30322, Georgia.
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33
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Du H, Wong MY, Zhang T, Santos MN, Hsu C, Zhang J, Yu H, Luo W, Hu F. A multifaceted role of progranulin in regulating amyloid-beta dynamics and responses. Life Sci Alliance 2021; 4:e202000874. [PMID: 34103390 PMCID: PMC8200295 DOI: 10.26508/lsa.202000874] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 05/26/2021] [Accepted: 05/26/2021] [Indexed: 01/07/2023] Open
Abstract
Haploinsufficiency of progranulin (PGRN) is a leading cause of frontotemporal lobar degeneration (FTLD). PGRN polymorphisms are associated with Alzheimer's disease. PGRN is highly expressed in the microglia near Aβ plaques and influences plaque dynamics and microglial activation. However, the detailed mechanisms remain elusive. Here we report that PGRN deficiency reduces human APP and Aβ levels in the young male but not female mice. PGRN-deficient microglia exhibit increased expression of markers associated with microglial activation, including CD68, galectin-3, TREM2, and GPNMB, specifically near Aβ plaques. In addition, PGRN loss leads to up-regulation of lysosome proteins and an increase in the nuclear localization of TFE3, a transcription factor involved in lysosome biogenesis. Cultured PGRN-deficient microglia show enhanced nuclear translocation of TFE3 and inflammation in response to Aβ fibril treatment. Taken together, our data revealed a sex- and age-dependent effect of PGRN on APP metabolism and a role of PGRN in regulating lysosomal activities and inflammation in plaque-associated microglia.
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Affiliation(s)
- Huan Du
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Man Ying Wong
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Tingting Zhang
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Mariela Nunez Santos
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Charlene Hsu
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Junke Zhang
- Department of Computational Biology, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Haiyuan Yu
- Department of Computational Biology, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Wenjie Luo
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
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34
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Kuang L, Hashimoto K, Huang EJ, Gentry MS, Zhu H. Frontotemporal dementia non-sense mutation of progranulin rescued by aminoglycosides. Hum Mol Genet 2021; 29:624-634. [PMID: 31913476 DOI: 10.1093/hmg/ddz280] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/22/2019] [Accepted: 11/19/2019] [Indexed: 02/06/2023] Open
Abstract
Frontotemporal dementia (FTD) is an early onset dementia characterized by progressive atrophy of the frontal and/or temporal lobes. FTD is highly heritable with mutations in progranulin accounting for 5-26% of cases in different populations. Progranulin is involved in endocytosis, secretion and lysosomal processes, but its functions under physiological and pathological conditions remains to be defined. Many FTD-causing non-sense progranulin mutations contain a premature termination codon (PTC), thus progranulin haploinsufficiency has been proposed as a major disease mechanism. Currently, there is no effective FTD treatment or therapy. Aminoglycosides are a class of antibiotics that possess a less-known function to induce eukaryotic ribosomal readthrough of PTCs to produce a full-length protein. The aminoglycoside-induced readthrough strategy has been utilized to treat multiple human diseases caused by PTCs. In this study, we tested the only clinically approved readthrough small molecule PTC124 and 11 aminoglycosides in a cell culture system on four PTCs responsible for FTD or a related neurodegenerative disease amyotrophic lateral sclerosis. We found that the aminoglycosides G418 and gentamicin rescued the expression of the progranulin R493X mutation. G418 was more effective than gentamicin (~50% rescue versus <10%), and the effect was dose- and time-dependent. The progranulin readthrough protein displayed similar subcellular localization as the wild-type progranulin protein. These data provide an exciting proof-of-concept that aminoglycosides or other readthrough-promoting compounds are a therapeutic avenue for familial FTD caused by progranulin PTC mutations.
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Affiliation(s)
- Lisha Kuang
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Kei Hashimoto
- Department of Pathology, University of California, San Francisco, CA 94143, USA
| | - Eric J Huang
- Department of Pathology, University of California, San Francisco, CA 94143, USA
| | - Matthew S Gentry
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Haining Zhu
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA.,Lexington VA Medical Center, Research & Development, Lexington, KY 40502, USA
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35
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Zhou X, Kukar T, Rademakers R. Lysosomal Dysfunction and Other Pathomechanisms in FTLD: Evidence from Progranulin Genetics and Biology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1281:219-242. [PMID: 33433878 DOI: 10.1007/978-3-030-51140-1_14] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
It has been more than a decade since heterozygous loss-of-function mutations in the progranulin gene (GRN) were first identified as an important genetic cause of frontotemporal lobar degeneration (FTLD). Due to the highly diverse biological functions of the progranulin (PGRN) protein, encoded by GRN, multiple possible disease mechanisms have been proposed. Early work focused on the neurotrophic properties of PGRN and its role in the inflammatory response. However, since the discovery of homozygous GRN mutations in patients with a lysosomal storage disorder, investigation into the possible roles of PGRN and its proteolytic cleavage products granulins, in lysosomal function and dysfunction, has taken center stage. In this chapter, we summarize the GRN mutational spectrum and its associated phenotypes followed by an in-depth discussion on the possible disease mechanisms implicated in FTLD-GRN. We conclude with key outstanding questions which urgently require answers to ensure safe and successful therapy development for GRN mutation carriers.
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Affiliation(s)
- Xiaolai Zhou
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Thomas Kukar
- Department of Pharmacology and Chemical Biology, Center for Neurodegenerative Disease, Emory University School of Medicine, Atlanta, GA, USA
| | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA.
- VIB Center for Molecular Neurology, University of Antwerp-CDE, Antwerp, Belgium.
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36
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Miyakawa S, Sakuma H, Warude D, Asanuma S, Arimura N, Yoshihara T, Tavares D, Hata A, Ida K, Hori Y, Okuzono Y, Yamamoto S, Iida K, Shimizu H, Kondo S, Sato S. Anti-sortilin1 Antibody Up-Regulates Progranulin via Sortilin1 Down-Regulation. Front Neurosci 2020; 14:586107. [PMID: 33384578 PMCID: PMC7770147 DOI: 10.3389/fnins.2020.586107] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 11/16/2020] [Indexed: 12/15/2022] Open
Abstract
Progranulin (PGRN) haploinsufficiency associated with loss-of-function mutations in the granulin gene causes frontotemporal dementia (FTD). This suggests that increasing PGRN levels could have promising therapeutic implications for patients carrying GRN mutations. In this study, we explored the therapeutic potential of sortilin1 (SORT1), a clearance receptor of PGRN, by generating and characterizing monoclonal antibodies against SORT1. Anti-SORT1 monoclonal antibodies were generated by immunizing Sort1 knockout mice with SORT1 protein. The antibodies were classified into 7 epitope bins based on their competitive binding to the SORT1 protein and further defined by epitope bin-dependent characteristics, including SORT1-PGRN blocking, SORT1 down-regulation, and binding to human and mouse SORT1. We identified a positive correlation between PGRN up-regulation and SORT1 down-regulation. Furthermore, we also characterized K1-67 antibody via SORT1 down-regulation and binding to mouse SORT1 in vivo and confirmed that K1-67 significantly up-regulated PGRN levels in plasma and brain interstitial fluid of mice. These data indicate that SORT1 down-regulation is a key mechanism in increasing PGRN levels via anti-SORT1 antibodies and suggest that SORT1 is a potential target to correct PGRN reduction, such as that in patients with FTD caused by GRN mutation.
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Affiliation(s)
- Shuuichi Miyakawa
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Hiroyuki Sakuma
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Dnyaneshwar Warude
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Satomi Asanuma
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Naoto Arimura
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Tomoki Yoshihara
- Global Biologics Research, Takeda Pharmaceutical Company Limited, Cambridge, MA, United States
| | - Daniel Tavares
- Global Biologics Research, Takeda Pharmaceutical Company Limited, Cambridge, MA, United States
| | - Akito Hata
- Global Biologics Research, Takeda Pharmaceutical Company Limited, Cambridge, MA, United States
| | - Koh Ida
- Global Biologics Research, Takeda Pharmaceutical Company Limited, Cambridge, MA, United States
| | - Yuri Hori
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Yuumi Okuzono
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Syunsuke Yamamoto
- Drug Metabolism and Pharmacokinetics Research Laboratories, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Koichi Iida
- Drug Metabolism and Pharmacokinetics Research Laboratories, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Hisao Shimizu
- Drug Metabolism and Pharmacokinetics Research Laboratories, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Shinichi Kondo
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Shuji Sato
- Immunology Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Japan
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37
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Bhopatkar AA, Rangachari V. Are granulins copper sequestering proteins? Proteins 2020; 89:450-461. [PMID: 33252789 DOI: 10.1002/prot.26031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 11/25/2020] [Indexed: 02/06/2023]
Abstract
Granulins (GRN 1-7) are short (~6 kDa), cysteine-rich proteins that are generated upon the proteolytic processing of progranulin (PGRN). These peptides, along with their precursor, have been implicated in multiple pathophysiological roles, especially in neurodegenerative diseases. Previously we showed that GRN-3 and GRN-5 are fully disordered in the reduced form implicating redox sensitive attributes to the proteins. Redox-based modulations are often carried out by metalloproteins in mitigating oxidative stress and maintaining metal-homeostasis within cells. To probe whether GRNs play a role in metal sequestration, we tested the metal binding propensity of the reduced forms of GRNs -3 and - 5 under neutral and acidic pH mimicking cytosolic and lysosomal conditions, respectively. We found, at neutral pH, both GRNs selectively bind Cu and no other divalent metal cations, with a greater specificity for Cu(I). Binding of Cu did not result in a disorder-to-order structural transition but partly triggered the multimerization of GRNs via uncoordinated cystines at both pH conditions. Overall, the results indicate that GRNs -3 and - 5 have surprisingly strong affinity for Cu in the pM range, comparable to other known copper sequestering proteins. The results also hint at a potential of GRNs to reduce Cu(II) to Cu(I), a process that has significance in mitigating Cu-induced ROS cytotoxicity in cells. Together, this report uncovers metal-coordinating property of GRNs for the first time, which may have profound significance in their structure and pathophysiological functions.
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Affiliation(s)
- Anukool A Bhopatkar
- Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences and, University of Southern Mississippi, Hattiesburg, Mississippi, USA
| | - Vijayaraghavan Rangachari
- Center for Molecular and Cellular Biosciences, University of Southern Mississippi, Hattiesburg, Mississippi, USA
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38
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Huang M, Modeste E, Dammer E, Merino P, Taylor G, Duong DM, Deng Q, Holler CJ, Gearing M, Dickson D, Seyfried NT, Kukar T. Network analysis of the progranulin-deficient mouse brain proteome reveals pathogenic mechanisms shared in human frontotemporal dementia caused by GRN mutations. Acta Neuropathol Commun 2020; 8:163. [PMID: 33028409 PMCID: PMC7541308 DOI: 10.1186/s40478-020-01037-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 09/13/2020] [Indexed: 02/08/2023] Open
Abstract
Heterozygous, loss-of-function mutations in the granulin gene (GRN) encoding progranulin (PGRN) are a common cause of frontotemporal dementia (FTD). Homozygous GRN mutations cause neuronal ceroid lipofuscinosis-11 (CLN11), a lysosome storage disease. PGRN is a secreted glycoprotein that can be proteolytically cleaved into seven bioactive 6 kDa granulins. However, it is unclear how deficiency of PGRN and granulins causes neurodegeneration. To gain insight into the mechanisms of FTD pathogenesis, we utilized Tandem Mass Tag isobaric labeling mass spectrometry to perform an unbiased quantitative proteomic analysis of whole-brain tissue from wild type (Grn+/+) and Grn knockout (Grn-/-) mice at 3- and 19-months of age. At 3-months lysosomal proteins (i.e. Gns, Scarb2, Hexb) are selectively increased indicating lysosomal dysfunction is an early consequence of PGRN deficiency. Additionally, proteins involved in lipid metabolism (Acly, Apoc3, Asah1, Gpld1, Ppt1, and Naaa) are decreased; suggesting lysosomal degradation of lipids may be impaired in the Grn-/- brain. Systems biology using weighted correlation network analysis (WGCNA) of the Grn-/- brain proteome identified 26 modules of highly co-expressed proteins. Three modules strongly correlated to Grn deficiency and were enriched with lysosomal proteins (Gpnmb, CtsD, CtsZ, and Tpp1) and inflammatory proteins (Lgals3, GFAP, CD44, S100a, and C1qa). We find that lysosomal dysregulation is exacerbated with age in the Grn-/- mouse brain leading to neuroinflammation, synaptic loss, and decreased markers of oligodendrocytes, myelin, and neurons. In particular, GPNMB and LGALS3 (galectin-3) were upregulated by microglia and elevated in FTD-GRN brain samples, indicating common pathogenic pathways are dysregulated in human FTD cases and Grn-/- mice. GPNMB levels were significantly increased in the cerebrospinal fluid of FTD-GRN patients, but not in MAPT or C9orf72 carriers, suggesting GPNMB could be a biomarker specific to FTD-GRN to monitor disease onset, progression, and drug response. Our findings support the idea that insufficiency of PGRN and granulins in humans causes neurodegeneration through lysosomal dysfunction, defects in autophagy, and neuroinflammation, which could be targeted to develop effective therapies.
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Modelling frontotemporal dementia using patient-derived induced pluripotent stem cells. Mol Cell Neurosci 2020; 109:103553. [PMID: 32956830 DOI: 10.1016/j.mcn.2020.103553] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 08/27/2020] [Accepted: 09/12/2020] [Indexed: 12/12/2022] Open
Abstract
Frontotemporal dementia (FTD) describes a group of clinically heterogeneous conditions that frequently affect people under the age of 65 (Le Ber et al., 2013). There are multiple genetic causes of FTD, including coding or splice-site mutations in MAPT, GRN mutations that lead to haploinsufficiency of progranulin protein, and a hexanucleotide GGGGCC repeat expansion in C9ORF72. Pathologically, FTD is characterised by abnormal protein accumulations in neurons and glia. These aggregates can be composed of the microtubule-associated protein tau (observed in FTD with MAPT mutations), the DNA/RNA-binding protein TDP-43 (seen in FTD with mutations in GRN or C9ORF72 repeat expansions) or dipeptide proteins generated by repeat associated non-ATG translation of the C9ORF72 repeat expansion. There are currently no disease-modifying therapies for FTD and the availability of in vitro models that recapitulate pathologies in a disease-relevant cell type would accelerate the development of novel therapeutics. It is now possible to generate patient-specific stem cells through the reprogramming of somatic cells from a patient with a genotype/phenotype of interest into induced pluripotent stem cells (iPSCs). iPSCs can subsequently be differentiated into a plethora of cell types including neurons, astrocytes and microglia. Using this approach has allowed researchers to generate in vitro models of genetic FTD in human cell types that are largely inaccessible during life. In this review we explore the recent progress in the use of iPSCs to model FTD, and consider the merits, limitations and future prospects of this approach.
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40
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Tayebi N, Lopez G, Do J, Sidransky E. Pro-cathepsin D, Prosaposin, and Progranulin: Lysosomal Networks in Parkinsonism. Trends Mol Med 2020; 26:913-923. [PMID: 32948448 DOI: 10.1016/j.molmed.2020.07.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/08/2020] [Accepted: 07/16/2020] [Indexed: 12/14/2022]
Abstract
Mutations in GBA1, the gene encoding the lysosomal hydrolase glucocerebrosidase (GCase), are a risk factor for parkinsonism. Pursuing the potential mechanisms underlying this risk in aging neurons, we propose a new network uniting three major lysosomal proteins: (i) cathepsin D (CTSD), which plays a major role in α-synuclein (SNCA) degradation and prosaposin (PSAP) cleavage; (ii) PSAP, essential for GCase activation and progranulin (PGRN) transport; and (iii) PGRN, impacting lysosomal biogenesis, PSAP trafficking, and CTSD maturation. We hypothesize that alterations to this network and associated receptors modify lysosomal function and subsequently impact both SNCA degradation and GCase activity. By exploring the interactions between this protein trio and each of their respective transporters and receptors, we may identify secondary risk factors that provide insight into the relationship between these lysosomal proteins, GCase, and SNCA, and reveal novel therapeutic targets.
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Affiliation(s)
- Nahid Tayebi
- Medical Genetics Branch, National Human Genetics Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Grisel Lopez
- Medical Genetics Branch, National Human Genetics Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jenny Do
- Medical Genetics Branch, National Human Genetics Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ellen Sidransky
- Medical Genetics Branch, National Human Genetics Research Institute, National Institutes of Health, Bethesda, MD, USA.
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41
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Werner G, Damme M, Schludi M, Gnörich J, Wind K, Fellerer K, Wefers B, Wurst W, Edbauer D, Brendel M, Haass C, Capell A. Loss of TMEM106B potentiates lysosomal and FTLD-like pathology in progranulin-deficient mice. EMBO Rep 2020; 21:e50241. [PMID: 32929860 PMCID: PMC7534633 DOI: 10.15252/embr.202050241] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 08/05/2020] [Accepted: 08/10/2020] [Indexed: 12/13/2022] Open
Abstract
Single nucleotide polymorphisms (SNPs) in TMEM106B encoding the lysosomal type II transmembrane protein 106B increase the risk for frontotemporal lobar degeneration (FTLD) of GRN (progranulin gene) mutation carriers. Currently, it is unclear if progranulin (PGRN) and TMEM106B are synergistically linked and if a gain or a loss of function of TMEM106B is responsible for the increased disease risk of patients with GRN haploinsufficiency. We therefore compare behavioral abnormalities, gene expression patterns, lysosomal activity, and TDP‐43 pathology in single and double knockout animals. Grn−/−/Tmem106b−/− mice show a strongly reduced life span and massive motor deficits. Gene expression analysis reveals an upregulation of molecular signature characteristic for disease‐associated microglia and autophagy. Dysregulation of maturation of lysosomal proteins as well as an accumulation of ubiquitinated proteins and widespread p62 deposition suggest that proteostasis is impaired. Moreover, while single Grn−/− knockouts only occasionally show TDP‐43 pathology, the double knockout mice exhibit deposition of phosphorylated TDP‐43. Thus, a loss of function of TMEM106B may enhance the risk for GRN‐associated FTLD by reduced protein turnover in the lysosomal/autophagic system.
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Affiliation(s)
- Georg Werner
- Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Markus Damme
- Institute of Biochemistry, Kiel University, Kiel, Germany
| | - Martin Schludi
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Johannes Gnörich
- Department of Nuclear Medicine, University Hospital, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Karin Wind
- Department of Nuclear Medicine, University Hospital, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Katrin Fellerer
- Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Benedikt Wefers
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany.,Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Wolfgang Wurst
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany.,Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Dieter Edbauer
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Matthias Brendel
- Department of Nuclear Medicine, University Hospital, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Christian Haass
- Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany.,German Center for Neurodegenerative Diseases (DZNE), Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Anja Capell
- Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
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42
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Lan Y, Li Z, Wang Z, Wang X, Wang G, Zhang J, Hu S, Zhao K, Xu B, Gao F, He W. An Experimental Model of Neurodegenerative Disease Based on Porcine Hemagglutinating Encephalomyelitis Virus-Related Lysosomal Abnormalities. Mol Neurobiol 2020; 57:5299-5306. [PMID: 32876841 PMCID: PMC7463228 DOI: 10.1007/s12035-020-02105-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/27/2020] [Indexed: 01/01/2023]
Abstract
Lysosomes are involved in pathogenesis of a variety of neurodegenerative diseases and play a large role in neurodegenerative disorders caused by virus infection. However, whether virus-infected cells or animals can be used as experimental models of neurodegeneration in humans based on virus-related lysosomal dysfunction remain unclear. Porcine hemagglutinating encephalomyelitis virus displays neurotropism in mice, and neural cells are its targets for viral progression. PHEV infection was confirmed to be a risk factor for neurodegenerative diseases in the present. The findings demonstrated for the first time that PHEV infection can lead to lysosome disorders and showed that the specific mechanism of lysosome dysfunction is related to PGRN expression deficiency and indicated similar pathogenesis compared with human neurodegenerative diseases upon PHEV infection. Trehalose can also increase progranulin expression and rescue abnormalities in lysosomal structure in PHEV-infected cells. In conclusion, these results suggest that PHEV probably serve as a disease model for studying the pathogenic mechanisms and prevention of other degenerative diseases.
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Affiliation(s)
- Yungang Lan
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Zi Li
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Zhenzhen Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xinran Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Gaili Wang
- Jilin Academy of Animal Husbandry and Veterinary Medicine, Changchun, Jilin, China
| | - Jing Zhang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shiyu Hu
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Kui Zhao
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Baofeng Xu
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, 130021, China
| | - Feng Gao
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Wenqi He
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China.
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Huin V, Barbier M, Bottani A, Lobrinus JA, Clot F, Lamari F, Chat L, Rucheton B, Fluchère F, Auvin S, Myers P, Gelot A, Camuzat A, Caillaud C, Jornéa L, Forlani S, Saracino D, Duyckaerts C, Brice A, Durr A, Le Ber I. Homozygous GRN mutations: new phenotypes and new insights into pathological and molecular mechanisms. Brain 2020; 143:303-319. [PMID: 31855245 DOI: 10.1093/brain/awz377] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 10/08/2019] [Accepted: 10/11/2019] [Indexed: 12/12/2022] Open
Abstract
Homozygous mutations in the progranulin gene (GRN) are associated with neuronal ceroid lipofuscinosis 11 (CLN11), a rare lysosomal-storage disorder characterized by cerebellar ataxia, seizures, retinitis pigmentosa, and cognitive disorders, usually beginning between 13 and 25 years of age. This is a rare condition, previously reported in only four families. In contrast, heterozygous GRN mutations are a major cause of frontotemporal dementia associated with neuronal cytoplasmic TDP-43 inclusions. We identified homozygous GRN mutations in six new patients. The phenotypic spectrum is much broader than previously reported, with two remarkably distinct presentations, depending on the age of onset. A childhood/juvenile form is characterized by classical CLN11 symptoms at an early age at onset. Unexpectedly, other homozygous patients presented a distinct delayed phenotype of frontotemporal dementia and parkinsonism after 50 years; none had epilepsy or cerebellar ataxia. Another major finding of this study is that all GRN mutations may not have the same impact on progranulin protein synthesis. A hypomorphic effect of some mutations is supported by the presence of residual levels of plasma progranulin and low levels of normal transcript detected in one case with a homozygous splice-site mutation and late onset frontotemporal dementia. This is a new critical finding that must be considered in therapeutic trials based on replacement strategies. The first neuropathological study in a homozygous carrier provides new insights into the pathological mechanisms of the disease. Hallmarks of neuronal ceroid lipofuscinosis were present. The absence of TDP-43 cytoplasmic inclusions markedly differs from observations of heterozygous mutations, suggesting a pathological shift between lysosomal and TDP-43 pathologies depending on the mono or bi-allelic status. An intriguing observation was the loss of normal TDP-43 staining in the nucleus of some neurons, which could be the first stage of the TDP-43 pathological process preceding the formation of typical cytoplasmic inclusions. Finally, this study has important implications for genetic counselling and molecular diagnosis. Semi-dominant inheritance of GRN mutations implies that specific genetic counselling should be delivered to children and parents of CLN11 patients, as they are heterozygous carriers with a high risk of developing dementia. More broadly, this study illustrates the fact that genetic variants can lead to different phenotypes according to their mono- or bi-allelic state, which is a challenge for genetic diagnosis.
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Affiliation(s)
- Vincent Huin
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France
| | - Mathieu Barbier
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France
| | - Armand Bottani
- Department of Genetic Medicine, University Hospital of Geneva, Geneva, Switzerland
| | | | - Fabienne Clot
- Department of Molecular and Cellular Neurogenetics, AP-HP, Pitié-Salpêtrière - Charles Foix University Hospitals, Paris, France
| | - Foudil Lamari
- AP-HP, Metabolic Biochemistry Unit, Department of Biochemistry of Neurometabolic Diseases, Pitié-Salpêtrière University Hospital, Paris, France
| | - Laureen Chat
- Department of Molecular and Cellular Neurogenetics, AP-HP, Pitié-Salpêtrière - Charles Foix University Hospitals, Paris, France
| | - Benoît Rucheton
- AP-HP, Metabolic Biochemistry Unit, Department of Biochemistry of Neurometabolic Diseases, Pitié-Salpêtrière University Hospital, Paris, France
| | - Frédérique Fluchère
- AP-HM, Department of Neurology and Movement Disorders, La Timone, Clinical Neuroscience Unit, Aix-Marseille University, France
| | - Stéphane Auvin
- AP-HP Department of Pediatric Neurology, Robert Debré University Hospital, F, Paris, France
| | | | - Antoinette Gelot
- Neuropathology, Department of Pathology, Trusseau Hospital, AP-HP, Paris, France and INMED INSERM U901 Luminy Campus, Aix-Marseille University, France
| | - Agnès Camuzat
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France
| | - Catherine Caillaud
- Biochemical, Metabolomical and Proteonomical Department, Necker-Enfants Malades University Hospital, AP-HP, F-75015 Paris, France
| | - Ludmila Jornéa
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France
| | - Sylvie Forlani
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France
| | - Dario Saracino
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France
| | - Charles Duyckaerts
- Department of Neuropathology 'Escourolle', AP-HP, Pitié-Salpêtrière University Hospital, Paris, France
| | - Alexis Brice
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France.,AP-HP, National Reference Center for Rare Diseases 'Neurogenetics', Pitié-Salpêtrière University Hospital, Paris, France
| | - Alexandra Durr
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France.,AP-HP, National Reference Center for Rare Diseases 'Neurogenetics', Pitié-Salpêtrière University Hospital, Paris, France
| | - Isabelle Le Ber
- Sorbonne Université, Institut du Cerveau et de la Moelle épinière (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France.,AP-HP, National Reference center 'rare and young dementias', IM2A, Pitié-Salpêtrière University Hospital, Paris, France
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44
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Feng T, Mai S, Roscoe JM, Sheng RR, Ullah M, Zhang J, Katz II, Yu H, Xiong W, Hu F. Loss of TMEM106B and PGRN leads to severe lysosomal abnormalities and neurodegeneration in mice. EMBO Rep 2020; 21:e50219. [PMID: 32852886 PMCID: PMC7534636 DOI: 10.15252/embr.202050219] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 06/25/2020] [Accepted: 07/14/2020] [Indexed: 12/12/2022] Open
Abstract
Haploinsufficiency of progranulin (PGRN) is a leading cause of frontotemporal lobar degeneration (FTLD). Loss of PGRN leads to lysosome dysfunction during aging. TMEM106B, a gene encoding a lysosomal membrane protein, is the main risk factor for FTLD with PGRN haploinsufficiency. But how TMEM106B affects FTLD disease progression remains to be determined. Here, we report that TMEM106B deficiency in mice leads to accumulation of lysosome vacuoles at the distal end of the axon initial segment in motor neurons and the development of FTLD‐related pathology during aging. Ablation of both PGRN and TMEM106B in mice results in severe neuronal loss and glial activation in the spinal cord, retina, and brain. Enlarged lysosomes are frequently found in both microglia and astrocytes. Loss of both PGRN and TMEM106B results in an increased accumulation of lysosomal vacuoles in the axon initial segment of motor neurons and enhances the manifestation of FTLD phenotypes with a much earlier onset. These results provide novel insights into the role of TMEM106B in the lysosome, in brain aging, and in FTLD pathogenesis.
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Affiliation(s)
- Tuancheng Feng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Shuyi Mai
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Jenn Marie Roscoe
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Rory R Sheng
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Mohammed Ullah
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Junke Zhang
- Department of Computational Biology, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Isabel Iscol Katz
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Haiyuan Yu
- Department of Computational Biology, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Wenjun Xiong
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
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45
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Zhou X, Brooks M, Jiang P, Koga S, Zuberi AR, Baker MC, Parsons TM, Castanedes-Casey M, Phillips V, Librero AL, Kurti A, Fryer JD, Bu G, Lutz C, Dickson DW, Rademakers R. Loss of Tmem106b exacerbates FTLD pathologies and causes motor deficits in progranulin-deficient mice. EMBO Rep 2020; 21:e50197. [PMID: 32761777 DOI: 10.15252/embr.202050197] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 06/26/2020] [Accepted: 07/14/2020] [Indexed: 11/09/2022] Open
Abstract
Progranulin (PGRN) and transmembrane protein 106B (TMEM106B) are important lysosomal proteins implicated in frontotemporal lobar degeneration (FTLD) and other neurodegenerative disorders. Loss-of-function mutations in progranulin (GRN) are a common cause of FTLD, while TMEM106B variants have been shown to act as disease modifiers in FTLD. Overexpression of TMEM106B leads to lysosomal dysfunction, while loss of Tmem106b ameliorates lysosomal and FTLD-related pathologies in young Grn-/- mice, suggesting that lowering TMEM106B might be an attractive strategy for therapeutic treatment of FTLD-GRN. Here, we generate and characterize older Tmem106b-/- Grn-/- double knockout mice, which unexpectedly show severe motor deficits and spinal cord motor neuron and myelin loss, leading to paralysis and premature death at 11-12 months. Compared to Grn-/- , Tmem106b-/- Grn-/- mice have exacerbated FTLD-related pathologies, including microgliosis, astrogliosis, ubiquitin, and phospho-Tdp43 inclusions, as well as worsening of lysosomal and autophagic deficits. Our findings confirm a functional interaction between Tmem106b and Pgrn and underscore the need to rethink whether modulating TMEM106B levels is a viable therapeutic strategy.
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Affiliation(s)
- Xiaolai Zhou
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Mieu Brooks
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Peizhou Jiang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Shunsuke Koga
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Aamir R Zuberi
- The Rare and Orphan Disease Center, JAX Center for Precision Genetics, Bar Harbor, ME, USA
| | - Matthew C Baker
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | | | | | | | | | - Aishe Kurti
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - John D Fryer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Cathleen Lutz
- The Rare and Orphan Disease Center, JAX Center for Precision Genetics, Bar Harbor, ME, USA
| | | | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA.,Applied and Translational Neurogenomics, VIB Center for Molecular Neurology, VIB, Antwerp, Belgium.,Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
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46
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Progranulin expression induced by follicle-stimulating hormone in ovarian cancer cell lines depends on the histological subtype. Med Oncol 2020; 37:59. [PMID: 32474861 DOI: 10.1007/s12032-020-01383-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/23/2020] [Indexed: 10/24/2022]
Abstract
Epithelial ovarian cancer (EOC) is a heterogeneous disease that can be categorized into four major histological subtypes. Its etiology remains poorly understood due mainly to this heterogeneity. Follicle-stimulating hormone (FSH) has been implicated as a risk factor in EOC and has been suggested that may influence the development of specific subtypes. In addition, FSH regulates different aspects of ovarian cancer tumorigenesis. FSH downstream target genes in EOC have not been fully identified. Progranulin (PGRN) overexpression is associated with cell proliferation, invasion, chemoresistance, and shortened overall survival in ovarian cancer. Recently, we demonstrated that PGRN expression is regulated through the PI3K signaling pathway in clear cell ovarian carcinoma (CCOC) cells. In contrast, we also demonstrated that PGRN synthesis in serous ovarian cancer (SOC) cells is regulated via PKC but not by the PI3K signaling pathway. Several studies have demonstrated that FSH induces PKC and PI3K activation. Thus, this study was to investigate the effect of FSH on PGRN production in the CCOC cell line TOV-21G as compared to the SOC cell lines SKOV3 and OVCAR3. Cultured TOV-21G, SKOV3, and OVCAR3 cells were incubated with different concentrations of FSH for 48 h. PGRN mRNA and protein expression were assessed by RT-PCR and Western blotting, while PGRN secretion was measured by ELISA. PGRN mRNA and protein expression, as well as PGRN secretion, significantly increased after FSH stimulation in TOV-21G but not in SKOV3 and OVCAR3 cells. These data indicate that FSH induces PGRN expression and secretion only in CCOC cells. Establishing specific features for CCOC could reveal potential diagnostic and therapeutic targets.
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Butler VJ, Gao F, Corrales CI, Cortopassi WA, Caballero B, Vohra M, Ashrafi K, Cuervo AM, Jacobson MP, Coppola G, Kao AW. Age- and stress-associated C. elegans granulins impair lysosomal function and induce a compensatory HLH-30/TFEB transcriptional response. PLoS Genet 2019; 15:e1008295. [PMID: 31398187 PMCID: PMC6703691 DOI: 10.1371/journal.pgen.1008295] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 08/21/2019] [Accepted: 07/07/2019] [Indexed: 12/11/2022] Open
Abstract
The progressive failure of protein homeostasis is a hallmark of aging and a common feature in neurodegenerative disease. As the enzymes executing the final stages of autophagy, lysosomal proteases are key contributors to the maintenance of protein homeostasis with age. We previously reported that expression of granulin peptides, the cleavage products of the neurodegenerative disease protein progranulin, enhance the accumulation and toxicity of TAR DNA binding protein 43 (TDP-43) in Caenorhabditis elegans (C. elegans). In this study we show that C. elegans granulins are produced in an age- and stress-dependent manner. Granulins localize to the endolysosomal compartment where they impair lysosomal protease expression and activity. Consequently, protein homeostasis is disrupted, promoting the nuclear translocation of the lysosomal transcription factor HLH-30/TFEB, and prompting cells to activate a compensatory transcriptional program. The three C. elegans granulin peptides exhibited distinct but overlapping functional effects in our assays, which may be due to amino acid composition that results in distinct electrostatic and hydrophobicity profiles. Our results support a model in which granulin production modulates a critical transition between the normal, physiological regulation of protease activity and the impairment of lysosomal function that can occur with age and disease.
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Affiliation(s)
- Victoria J. Butler
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, California, United States of America
| | - Fuying Gao
- Semel Institute for Neuroscience and Human Behavior, Departments of Psychiatry and Biobehavioral Sciences and Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Christian I. Corrales
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, California, United States of America
| | - Wilian A. Cortopassi
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, United States of America
| | - Benjamin Caballero
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Mihir Vohra
- Department of Physiology, University of California, San Francisco, California, United States of America
| | - Kaveh Ashrafi
- Department of Physiology, University of California, San Francisco, California, United States of America
| | - Ana Maria Cuervo
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, New York, New York, United States of America
| | - Matthew P. Jacobson
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, United States of America
| | - Giovanni Coppola
- Semel Institute for Neuroscience and Human Behavior, Departments of Psychiatry and Biobehavioral Sciences and Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Aimee W. Kao
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, California, United States of America
- * E-mail:
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48
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Zhou X, Paushter DH, Pagan MD, Kim D, Nunez Santos M, Lieberman RL, Overkleeft HS, Sun Y, Smolka MB, Hu F. Progranulin deficiency leads to reduced glucocerebrosidase activity. PLoS One 2019; 14:e0212382. [PMID: 31291241 PMCID: PMC6619604 DOI: 10.1371/journal.pone.0212382] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/19/2019] [Indexed: 12/21/2022] Open
Abstract
Mutation in the GRN gene, encoding the progranulin (PGRN) protein, shows a dose-dependent disease correlation, wherein haploinsufficiency results in frontotemporal lobar degeneration (FTLD) and complete loss results in neuronal ceroid lipofuscinosis (NCL). Although the exact function of PGRN is unknown, it has been increasingly implicated in lysosomal physiology. Here we report that PGRN interacts with the lysosomal enzyme, glucocerebrosidase (GCase), and is essential for proper GCase activity. GCase activity is significantly reduced in tissue lysates from PGRN-deficient mice. This is further evidence that reduced lysosomal hydrolase activity may be a pathological mechanism in cases of GRN-related FTLD and NCL.
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Affiliation(s)
- Xiaolai Zhou
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, United States of America
| | - Daniel H. Paushter
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, United States of America
| | - Mitchell D. Pagan
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, United States of America
| | - Dongsung Kim
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, United States of America
| | - Mariela Nunez Santos
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, United States of America
| | - Raquel L. Lieberman
- School of Chemistry and Biochemistry, Georgia Institute of Technology, NW, Atlanta, GA, United States of America
| | - Herman S. Overkleeft
- Leiden Institute of Chemistry, Leiden University, Gorlaeus Laboratories, RA Leiden, Netherlands
| | - Ying Sun
- Division of Human Genetics; Cincinnati Children's Hospital Medical Center and the Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States of America
| | - Marcus B. Smolka
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, United States of America
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, United States of America
- * E-mail:
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49
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Peng W, Minakaki G, Nguyen M, Krainc D. Preserving Lysosomal Function in the Aging Brain: Insights from Neurodegeneration. Neurotherapeutics 2019; 16:611-634. [PMID: 31183763 PMCID: PMC6694346 DOI: 10.1007/s13311-019-00742-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Lysosomes are acidic, membrane-bound organelles that serve as the primary catabolic compartment of the cell. They are crucial to a variety of cellular processes from nutrient storage to autophagy. Given the diversity of lysosomal functions, it is unsurprising that lysosomes are also emerging as important players in aging. Lysosomal dysfunction is implicated in several aging-related neurodegenerative diseases including Alzheimer's, Parkinson's, amyotrophic lateral sclerosis/frontotemporal dementia, and Huntington's. Although the precise role of lysosomes in the aging brain is not well-elucidated, some insight into their function has been gained from our understanding of the pathophysiology of age-dependent neurodegenerative diseases. Therapeutic strategies targeting lysosomes and autophagic machinery have already been tested in several of these diseases with promising results, suggesting that improving lysosomal function could be similarly beneficial in preserving function in the aging brain.
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Affiliation(s)
- Wesley Peng
- The Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, 60611, USA
| | - Georgia Minakaki
- The Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, 60611, USA
| | - Maria Nguyen
- The Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, 60611, USA
| | - Dimitri Krainc
- The Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, 60611, USA.
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50
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Butler VJ, Cortopassi WA, Gururaj S, Wang AL, Pierce OM, Jacobson MP, Kao AW. Multi-Granulin Domain Peptides Bind to Pro-Cathepsin D and Stimulate Its Enzymatic Activity More Effectively Than Progranulin in Vitro. Biochemistry 2019; 58:2670-2674. [PMID: 31099551 DOI: 10.1021/acs.biochem.9b00275] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Progranulin (PGRN) is an evolutionarily conserved glycoprotein associated with several disease states, including neurodegeneration, cancer, and autoimmune disorders. This protein has recently been implicated in the regulation of lysosome function, whereby PGRN may bind to and promote the maturation and activity of the aspartyl protease cathepsin D (proCTSD, inactive precursor; matCTSD, mature, enzymatically active form). As the full-length PGRN protein can be cleaved into smaller peptides, called granulins, we assessed the function of these granulin peptides in binding to proCTSD and stimulating matCTSD enzyme activity in vitro. Here, we report that full-length PGRN and multi-granulin domain peptides bound to proCTSD with low to submicromolar binding affinities. This binding promoted proCTSD destabilization, the magnitude of which was greater for multi-granulin domain peptides than for full-length PGRN. Such destabilization correlated with enhanced matCTSD activity at acidic pH. The presence and function of multi-granulin domain peptides have typically been overlooked in previous studies. This work provides the first in vitro quantification of their binding and activity on proCTSD. Our study highlights the significance of multi-granulin domain peptides in the regulation of proCTSD maturation and enzymatic activity and suggests that attention to PGRN processing will be essential for the future understanding of the molecular mechanisms leading to neurodegenerative disease states with loss-of-function mutations in PGRN.
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Affiliation(s)
- Victoria J Butler
- Department of Neurology , University of California , San Francisco , California 94143 , United States
| | - Wilian A Cortopassi
- Department of Pharmaceutical Chemistry , University of California , San Francisco , California 94143 , United States
| | - Sushmitha Gururaj
- Department of Neurology , University of California , San Francisco , California 94143 , United States
| | - Austin L Wang
- Department of Neurology , University of California , San Francisco , California 94143 , United States
| | - Olivia M Pierce
- Department of Pharmaceutical Chemistry , University of California , San Francisco , California 94143 , United States
| | - Matthew P Jacobson
- Department of Pharmaceutical Chemistry , University of California , San Francisco , California 94143 , United States
| | - Aimee W Kao
- Department of Neurology , University of California , San Francisco , California 94143 , United States
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