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Guan D, Huang P, Liu X, Li Q, Zhang X, Liu N, Wang Y, Wan Y, Chai J, Cai S, Chen R, Ye Z. Deficiency of myeloid NPC1 exacerbates liver injury and fibrosis by impairing macrophage efferocytosis. J Adv Res 2025; 72:213-227. [PMID: 39547438 DOI: 10.1016/j.jare.2024.11.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2024] [Revised: 10/31/2024] [Accepted: 11/12/2024] [Indexed: 11/17/2024] Open
Abstract
INTRODUCTION Niemann-Pick C1 (NPC1), a lysosomal cholesterol transport protein, is required for efficient efferocytosis. Patients with Npc1 mutation are frequently accompanied with hepatic symptoms, including hepatomegaly, elevated liver transaminases, or even acute liver failure, but the pathogenic mechanism remains unknown. OBJECTIVES Our work aims to characterize the functional role of myeloid NPC1 in liver injury and elucidate its underlying mechanism. METHODS Analyses of injured livers from patients with liver diseases and mouse models were conducted to examine NPC1 expression. Myeloid cell-specific Npc1 knockout mice were constructed to determine the functional role of macrophage NPC1 in liver injury. Isolated macrophages were subjected to in vitro mechanistical assays. RESULTS We found that NPC1 is mainly expressed in hepatic macrophages. Its mRNA and protein expression are significantly elevated in injured livers from both patients and mouse models. Tissue-specific deletion of myeloid Npc1 increased liver inflammation, levels of serum liver function enzymes, and liver fibrosis in mouse models of liver injury induced by carbon tetrachloride (CCl4) injection and methionine-and-choline-deficient (MCD) diets. Further analyses indicate that Npc1 deficiency in mouse models of liver injury resulted in increased levels of serum HMGB1 and mitochondrial DNA, promoted hepatic macrophage proinflammatory activation, M1 polarization, led to overproduction of hepatic inflammatory cytokines/chemokines, e.g. CCL2 and STING/NFκB pathway activation. In vitro mechanistical studies reveal that Npc1-deficient macrophages exhibited inefficient efferocytosis, partly due to impaired cargo degradation. CONCLUSIONS These findings indicate that elevated expression of myeloid NPC1 in liver diseases protects liver from injury by promoting macrophage efferocytosis of damaged cells. Dysfunction of NPC1 aggravates liver injury, suggesting that NPC1 may be a potential therapeutic target for treating liver diseases.
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Affiliation(s)
- Dongwei Guan
- Laboratory Animal Research Center, School of Medicine, Chongqing University, Chongqing 400044, China.
| | - Pengju Huang
- Laboratory Animal Research Center, School of Medicine, Chongqing University, Chongqing 400044, China
| | - Xinlei Liu
- Laboratory Animal Research Center, School of Medicine, Chongqing University, Chongqing 400044, China
| | - Qing Li
- Laboratory Animal Research Center, School of Medicine, Chongqing University, Chongqing 400044, China
| | - Xiaoxun Zhang
- Department of Gastroenterology, Institute of Digestive Diseases of PLA, Cholestatic Liver Diseases Center and Center for Metabolic-Associated Fatty Liver Disease, The First Affiliated Hospital (Southwest Hospital), Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Nan Liu
- Department of Urology Oncological Surgery, Chongqing University Cancer Hospital, Chongqing 400030, China
| | - Yong Wang
- Department of Laboratory Animal Science, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Ying Wan
- Biomedical Analysis Center, Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Jin Chai
- Department of Gastroenterology, Institute of Digestive Diseases of PLA, Cholestatic Liver Diseases Center and Center for Metabolic-Associated Fatty Liver Disease, The First Affiliated Hospital (Southwest Hospital), Third Military Medical University (Army Medical University), Chongqing 400038, China
| | - Shiying Cai
- Department of Internal Medicine and Liver Center, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Rui Chen
- Department of Pathology, Chongqing University Cancer Hospital, Chongqing 400030, China.
| | - Zhijia Ye
- Laboratory Animal Research Center, School of Medicine, Chongqing University, Chongqing 400044, China.
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2
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Huang R, Pang Q, Zheng L, Lin J, Li H, Wan L, Wang T. Cholesterol metabolism: physiological versus pathological aspects in intracerebral hemorrhage. Neural Regen Res 2025; 20:1015-1030. [PMID: 38989934 PMCID: PMC11438341 DOI: 10.4103/nrr.nrr-d-23-01462] [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: 08/31/2023] [Revised: 12/19/2023] [Accepted: 01/27/2024] [Indexed: 07/12/2024] Open
Abstract
Cholesterol is an important component of plasma membranes and participates in many basic life functions, such as the maintenance of cell membrane stability, the synthesis of steroid hormones, and myelination. Cholesterol plays a key role in the establishment and maintenance of the central nervous system. The brain contains 20% of the whole body's cholesterol, 80% of which is located within myelin. A huge number of processes (e.g., the sterol regulatory element-binding protein pathway and liver X receptor pathway) participate in the regulation of cholesterol metabolism in the brain via mechanisms that include cholesterol biosynthesis, intracellular transport, and efflux. Certain brain injuries or diseases involving crosstalk among the processes above can affect normal cholesterol metabolism to induce detrimental consequences. Therefore, we hypothesized that cholesterol-related molecules and pathways can serve as therapeutic targets for central nervous system diseases. Intracerebral hemorrhage is the most severe hemorrhagic stroke subtype, with high mortality and morbidity. Historical cholesterol levels are associated with the risk of intracerebral hemorrhage. Moreover, secondary pathological changes after intracerebral hemorrhage are associated with cholesterol metabolism dysregulation, such as neuroinflammation, demyelination, and multiple types of programmed cell death. Intracellular cholesterol accumulation in the brain has been found after intracerebral hemorrhage. In this paper, we review normal cholesterol metabolism in the central nervous system, the mechanisms known to participate in the disturbance of cholesterol metabolism after intracerebral hemorrhage, and the links between cholesterol metabolism and cell death. We also review several possible and constructive therapeutic targets identified based on cholesterol metabolism to provide cholesterol-based perspectives and a reference for those interested in the treatment of intracerebral hemorrhage.
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Affiliation(s)
- Ruoyu Huang
- Department of Forensic Science, School of Basic Medicine and Biological Sciences, Suzhou Medicine College of Soochow University, Suzhou, Jiangsu Province, China
| | - Qiuyu Pang
- Department of Forensic Science, School of Basic Medicine and Biological Sciences, Suzhou Medicine College of Soochow University, Suzhou, Jiangsu Province, China
| | - Lexin Zheng
- Department of Forensic Science, School of Basic Medicine and Biological Sciences, Suzhou Medicine College of Soochow University, Suzhou, Jiangsu Province, China
| | - Jiaxi Lin
- Department of Forensic Science, School of Basic Medicine and Biological Sciences, Suzhou Medicine College of Soochow University, Suzhou, Jiangsu Province, China
| | - Hanxi Li
- Department of Forensic Science, School of Basic Medicine and Biological Sciences, Suzhou Medicine College of Soochow University, Suzhou, Jiangsu Province, China
| | - Lingbo Wan
- Department of Forensic Science, School of Basic Medicine and Biological Sciences, Suzhou Medicine College of Soochow University, Suzhou, Jiangsu Province, China
| | - Tao Wang
- Department of Forensic Science, School of Basic Medicine and Biological Sciences, Suzhou Medicine College of Soochow University, Suzhou, Jiangsu Province, China
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3
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Du X, Wang HL. Rare Liver Diseases With Near-Normal Histology: A Review Focusing on Metabolic, Storage, and Inclusion Disorders. Adv Anat Pathol 2025:00125480-990000000-00139. [PMID: 39973759 DOI: 10.1097/pap.0000000000000488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2025]
Abstract
Despite the growing availability of noninvasive and faster diagnostic modalities, biopsy remains an important tool in the diagnosis and management of liver diseases. However, it is not uncommon that liver biopsies reveal normal or near normal histologic findings in patients with abnormal liver biochemistries, elevated autoantibodies, clinical findings suggestive of portal hypertension, systemic autoimmune or inflammatory diseases, hepatomegaly, cirrhosis by imaging, or other indications. These scenarios present significant diagnostic challenges and are rarely discussed in detail in the literature or textbooks. This article aims to provide a comprehensive review of a group of selected rare liver diseases, with a focus on metabolic, storage and inclusion disorders, that may exhibit a near-normal histology on biopsy. By recognizing subtle histologic features and correlating with clinical history, laboratory results and imaging findings, it is often possible to narrow down the differential diagnosis. In many cases, this integrative approach can yield a definitive diagnosis, allowing for tailored treatment and better patient outcomes.
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Affiliation(s)
- Xiaotang Du
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine and Ronald Reagan UCLA Medical Center, University of California Los Angeles, Los Angeles, CA
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4
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Abstract
Arimoclomol (MIPLYFFA™), an oral small molecule that crosses the blood brain barrier and is thought to upregulate CLEAR (Coordinated Lysosomal Expression and Regulation) network genes and improve lysosomal function, is being developed by Zevra Therapeutics Inc., for the treatment of neurological manifestations of Niemann-Pick disease type C (NPC). In September 2024, arimoclomol was approved for use in combination with miglustat for the treatment of neurological manifestations of NPC in adult and pediatric patients 2 years of age and older in the USA. This article summarizes the milestones in the development of arimoclomol leading to this first approval for use in combination with miglustat for the treatment of neurological manifestations of NPC in adult and pediatric patients aged ≥ 2 years.
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Affiliation(s)
- Susan J Keam
- Springer Nature, Private Bag 65901, Mairangi Bay, Auckland, 0754, New Zealand.
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5
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Kerschbaum HH, Gerner C, Oberascher K, Steiner P, Schürz M, Bresgen N. Lipid-nanoparticle-induced vacuolization in microglia. Commun Biol 2024; 7:1558. [PMID: 39580571 PMCID: PMC11585578 DOI: 10.1038/s42003-024-07271-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 11/14/2024] [Indexed: 11/25/2024] Open
Abstract
Lipid-containing vacuoles in microglia were discovered more than one hundred years ago in the brain of patients showing neurodegenerative processes. Recently, molecular-biological studies demonstrated specific changes in lipid-metabolism related to neurodegeneration. Despite that already Alzheimer described a distinct glia phenotype having large, lipid-containing vacuoles (Gitterzellen), little is known about how microglia convert lipid metabolites into a vacuolated phenotype. We studied the impact of liver-derived, insoluble, lipid-enriched nanoparticles (Lef-NP) ( ~ 20 nm) and of ceramide-coated Percoll-nanoparticles (Cer-NP) ( ~ 20 nm) on vacuolization in microglia. Lipidomic analysis of Lef-NP revealed numerous distinct lipids, including pro-inflammatory ceramides, which are enriched in the brain of Alzheimer patients. Video microscopy revealed that hepatocyte-derived Lef-NP and Cer-NP enhanced macropinocytosis, followed by macropinosome swelling and formation of the Gitterzellen phenotype. Neither ceramide nor Percoll-nanoparticles induced Gitterzellen-formation. Electron-tomography visualized membrane contact-sites between nanoparticle-loaded endosomes, endoplasmic reticulum cisternae and mitochondria. Suppression of lipid-nanoparticle-induced Gitterzellen-formation by amiloride, which supresses macropinocytosis, and bafilomycin A, an endosomal acidification inhibitor, further confirmed a pinocytotic pathway in Gitterzellen-formation. Bafilomycin A also reversed Gitterzellen to a ramified microglia phenotype. Our experimental findings suggest that lipid-nanoparticles but not emulsified lipids provoke vacuolization in microglia, and provide a simple in-vitro model for a pathogenic process taking years in the human brain.
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Affiliation(s)
- Hubert H Kerschbaum
- Department of Biosciences and Medical Biology, University of Salzburg, Salzburg, Austria.
- Centre for Cognitive Neuroscience, University of Salzburg, Salzburg, Austria.
| | - Christopher Gerner
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Karin Oberascher
- Department of Biosciences and Medical Biology, University of Salzburg, Salzburg, Austria
| | - Philip Steiner
- Institute of Pharmacology, Faculty of Medicine, Johannes Kepler University Linz, Linz, Austria
| | - Melanie Schürz
- Department of Biosciences and Medical Biology, University of Salzburg, Salzburg, Austria
| | - Nikolaus Bresgen
- Department of Biosciences and Medical Biology, University of Salzburg, Salzburg, Austria
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6
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Scrima S, Lambrughi M, Tiberti M, Fadda E, Papaleo E. ASM variants in the spotlight: A structure-based atlas for unraveling pathogenic mechanisms in lysosomal acid sphingomyelinase. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167260. [PMID: 38782304 DOI: 10.1016/j.bbadis.2024.167260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 04/30/2024] [Accepted: 05/18/2024] [Indexed: 05/25/2024]
Abstract
Lysosomal acid sphingomyelinase (ASM), a critical enzyme in lipid metabolism encoded by the SMPD1 gene, plays a crucial role in sphingomyelin hydrolysis in lysosomes. ASM deficiency leads to acid sphingomyelinase deficiency, a rare genetic disorder with diverse clinical manifestations, and the protein can be found mutated in other diseases. We employed a structure-based framework to comprehensively understand the functional implications of ASM variants, integrating pathogenicity predictions with molecular insights derived from a molecular dynamics simulation in a lysosomal membrane environment. Our analysis, encompassing over 400 variants, establishes a structural atlas of missense variants of lysosomal ASM, associating mechanistic indicators with pathogenic potential. Our study highlights variants that influence structural stability or exert local and long-range effects at functional sites. To validate our predictions, we compared them to available experimental data on residual catalytic activity in 135 ASM variants. Notably, our findings also suggest applications of the resulting data for identifying cases suited for enzyme replacement therapy. This comprehensive approach enhances the understanding of ASM variants and provides valuable insights for potential therapeutic interventions.
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Affiliation(s)
- Simone Scrima
- Cancer Structural Biology, Center for Autophagy, Recycling and Disease, Danish Cancer Institute, 2100 Copenhagen, Denmark; Cancer Systems Biology, Section for Bioinformatics, Department of Health and Technology, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Matteo Lambrughi
- Cancer Structural Biology, Center for Autophagy, Recycling and Disease, Danish Cancer Institute, 2100 Copenhagen, Denmark
| | - Matteo Tiberti
- Cancer Structural Biology, Center for Autophagy, Recycling and Disease, Danish Cancer Institute, 2100 Copenhagen, Denmark
| | - Elisa Fadda
- Department of Chemistry and Hamilton Institute, Maynooth University, Maynooth, co. Kildare, Ireland
| | - Elena Papaleo
- Cancer Structural Biology, Center for Autophagy, Recycling and Disease, Danish Cancer Institute, 2100 Copenhagen, Denmark; Cancer Systems Biology, Section for Bioinformatics, Department of Health and Technology, Technical University of Denmark, 2800 Lyngby, Denmark.
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7
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Muñoz-Oreja M, Sandoval A, Bruland O, Perez-Rodriguez D, Fernandez-Pelayo U, de Arbina AL, Villar-Fernandez M, Hernández-Eguiazu H, Hernández I, Park Y, Goicoechea L, Pascual-Frías N, Garcia-Ruiz C, Fernandez-Checa J, Martí-Carrera I, Gil-Bea FJ, Hasan MT, Gegg ME, Bredrup C, Knappskog PM, Gereñu-Lopetegui G, Varhaug KN, Bindoff LA, Spinazzola A, Yoon WH, Holt IJ. Elevated cholesterol in ATAD3 mutants is a compensatory mechanism that leads to membrane cholesterol aggregation. Brain 2024; 147:1899-1913. [PMID: 38242545 PMCID: PMC11068212 DOI: 10.1093/brain/awae018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/29/2023] [Accepted: 12/16/2023] [Indexed: 01/21/2024] Open
Abstract
Aberrant cholesterol metabolism causes neurological disease and neurodegeneration, and mitochondria have been linked to perturbed cholesterol homeostasis via the study of pathological mutations in the ATAD3 gene cluster. However, whether the cholesterol changes were compensatory or contributory to the disorder was unclear, and the effects on cell membranes and the wider cell were also unknown. Using patient-derived cells, we show that cholesterol perturbation is a conserved feature of pathological ATAD3 variants that is accompanied by an expanded lysosome population containing membrane whorls characteristic of lysosomal storage diseases. Lysosomes are also more numerous in Drosophila neural progenitor cells expressing mutant Atad3, which exhibit abundant membrane-bound cholesterol aggregates, many of which co-localize with lysosomes. By subjecting the Drosophila Atad3 mutant to nutrient restriction and cholesterol supplementation, we show that the mutant displays heightened cholesterol dependence. Collectively, these findings suggest that elevated cholesterol enhances tolerance to pathological ATAD3 variants; however, this comes at the cost of inducing cholesterol aggregation in membranes, which lysosomal clearance only partly mitigates.
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Affiliation(s)
- Mikel Muñoz-Oreja
- Department of Neurosciences, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain
- University of the Basque Country—Bizkaia Campus, 48940 Bilbao, Spain
- CIBERNED (Center for Networked Biomedical Research on Neurodegenerative Diseases, Ministry of Economy and Competitiveness, Institute Carlos III), 28031 Madrid, Spain
| | - Abigail Sandoval
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Ove Bruland
- Department of Medical Genetics, Haukeland University Hospital, Bergen 5021, Norway
| | - Diego Perez-Rodriguez
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London NW3 2PF, UK
| | - Uxoa Fernandez-Pelayo
- Department of Neurosciences, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain
| | - Amaia Lopez de Arbina
- Department of Neurosciences, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain
| | - Marina Villar-Fernandez
- Department of Neurosciences, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain
| | | | - Ixiar Hernández
- University of the Basque Country—Bizkaia Campus, 48940 Bilbao, Spain
| | - Yohan Park
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Leire Goicoechea
- Department of Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, 08036 Barcelona, Spain
- Liver Unit, Hospital Clinic i Provincial de Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain
- Centro de Investigación Biomédica en Red (CIBEREHD), 08036 Barcelona, Spain
| | - Nerea Pascual-Frías
- Department of Neurosciences, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain
- Center for Cooperative Research in Biomaterials (CIC BiomaGUNE), Basque Research and Technology Alliance (BRTA), 20014 San Sebastian, Spain
| | - Carmen Garcia-Ruiz
- Department of Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, 08036 Barcelona, Spain
- Liver Unit, Hospital Clinic i Provincial de Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain
- Centro de Investigación Biomédica en Red (CIBEREHD), 08036 Barcelona, Spain
| | - Jose Fernandez-Checa
- Department of Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, 08036 Barcelona, Spain
- Liver Unit, Hospital Clinic i Provincial de Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain
- Centro de Investigación Biomédica en Red (CIBEREHD), 08036 Barcelona, Spain
- Research Center for ALPD, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Itxaso Martí-Carrera
- Department of Neurosciences, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain
- University of the Basque Country—Bizkaia Campus, 48940 Bilbao, Spain
- CIBERNED (Center for Networked Biomedical Research on Neurodegenerative Diseases, Ministry of Economy and Competitiveness, Institute Carlos III), 28031 Madrid, Spain
- Pediatric Neurology, Hospital Universitario Donostia, 20014 San Sebastián, Spain
| | | | - Mazahir T Hasan
- Laboratory of Brain Circuits Therapeutics, Achucarro Basque Center for Neuroscience, Barrio Sarriena, s/n, E-48940 Leioa, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Matthew E Gegg
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London NW3 2PF, UK
| | - Cecilie Bredrup
- Department of Ophthalmology, Haukeland University Hospital, Bergen 5021, Norway
- Department of Clinical Medicine (K1), University of Bergen, Bergen 5020, Norway
| | | | - Gorka Gereñu-Lopetegui
- Department of Neurosciences, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain
- University of the Basque Country—Bizkaia Campus, 48940 Bilbao, Spain
- CIBERNED (Center for Networked Biomedical Research on Neurodegenerative Diseases, Ministry of Economy and Competitiveness, Institute Carlos III), 28031 Madrid, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Kristin N Varhaug
- Department of Clinical Medicine (K1), University of Bergen, Bergen 5020, Norway
- Department of Neurology, Haukeland University Hospital, Bergen 5021, Norway
| | - Laurence A Bindoff
- Department of Ophthalmology, Haukeland University Hospital, Bergen 5021, Norway
- Department of Clinical Medicine (K1), University of Bergen, Bergen 5020, Norway
- Department of Neurology, Haukeland University Hospital, Bergen 5021, Norway
| | - Antonella Spinazzola
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London NW3 2PF, UK
| | - Wan Hee Yoon
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Ian J Holt
- Department of Neurosciences, Biogipuzkoa Health Research Institute, 20014 San Sebastian, Spain
- University of the Basque Country—Bizkaia Campus, 48940 Bilbao, Spain
- CIBERNED (Center for Networked Biomedical Research on Neurodegenerative Diseases, Ministry of Economy and Competitiveness, Institute Carlos III), 28031 Madrid, Spain
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Royal Free Campus, London NW3 2PF, UK
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
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8
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Farhat NY, Alexander D, McKee K, Iben J, Rodriguez-Gil JL, Wassif CA, Cawley NX, Balch WE, Porter FD. Sterol O-Acyltransferase 1 ( SOAT1): A Genetic Modifier of Niemann-Pick Disease, Type C1. Int J Mol Sci 2024; 25:4217. [PMID: 38673803 PMCID: PMC11050712 DOI: 10.3390/ijms25084217] [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: 03/20/2024] [Revised: 04/02/2024] [Accepted: 04/07/2024] [Indexed: 04/28/2024] Open
Abstract
Niemann-Pick disease type C1 (NPC1) is a lysosomal disorder due to impaired intracellular cholesterol transport out of the endolysosomal compartment.. Marked heterogeneity has been observed in individuals with the same NPC1 genotype, thus suggesting a significant effect of modifier genes. Prior work demonstrated that decreased SOAT1 activity decreased disease severity in an NPC1 mouse model. Thus, we hypothesized that a polymorphism associated with decreased SOAT1 expression might influence the NPC1 phenotype. Phenotyping and genomic sequencing of 117 individuals with NPC1 was performed as part of a Natural History trial. Phenotyping included determination of disease severity and disease burden. Significant clinical heterogeneity is present in individuals homozygous for the NPC1I1061T variant and in siblings. Analysis of the SOAT1 polymorphism, rs1044925 (A>C), showed a significant association of the C-allele with earlier age of neurological onset. The C-allele may be associated with a higher Annualized Severity Index Score as well as increased frequency of liver disease and seizures. A polymorphism associated with decreased expression of SOAT1 appears to be a genetic modifier of the NPC1 phenotype. This finding is consistent with prior data showing decreased phenotypic severity in Npc1-/-:Soat1-/- mice and supports efforts to investigate the potential of SOAT1 inhibitors as a potential therapy for NPC1.
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Affiliation(s)
- Nicole Y. Farhat
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.Y.F.); (D.A.); (K.M.); (C.A.W.); (N.X.C.)
| | - Derek Alexander
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.Y.F.); (D.A.); (K.M.); (C.A.W.); (N.X.C.)
| | - Kyli McKee
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.Y.F.); (D.A.); (K.M.); (C.A.W.); (N.X.C.)
| | - James Iben
- Molecular Genomics Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA;
| | - Jorge L. Rodriguez-Gil
- Division of Medical Genetics, Division of Neonatal and Developmental Medicine, Department of Pediatrics, Stanford University, Palo Alto, CA 94304, USA;
| | - Christopher A. Wassif
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.Y.F.); (D.A.); (K.M.); (C.A.W.); (N.X.C.)
| | - Niamh X. Cawley
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.Y.F.); (D.A.); (K.M.); (C.A.W.); (N.X.C.)
| | - William E. Balch
- Department of Molecular Medicine, Scripps Research, La Jolla, CA 92037, USA;
| | - Forbes D. Porter
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.Y.F.); (D.A.); (K.M.); (C.A.W.); (N.X.C.)
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9
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Malara M, Prestel M, Tahirovic S. Endo-lysosomal dysfunction and neuronal-glial crosstalk in Niemann-Pick type C disease. Philos Trans R Soc Lond B Biol Sci 2024; 379:20220388. [PMID: 38368932 PMCID: PMC10874755 DOI: 10.1098/rstb.2022.0388] [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: 03/21/2023] [Accepted: 11/27/2023] [Indexed: 02/20/2024] Open
Abstract
Niemann-Pick type C (NPC) disease is a rare progressive lysosomal lipid storage disorder that manifests with a heterogeneous spectrum of clinical syndromes, including visceral, neurological and psychiatric symptoms. This monogenetic autosomal recessive disease is largely caused by mutations in the NPC1 gene, which controls intracellular lipid homeostasis. Vesicle-mediated endo-lysosomal lipid trafficking and non-vesicular lipid exchange via inter-organelle membrane contact sites are both regulated by the NPC1 protein. Loss of NPC1 function therefore triggers intracellular accumulation of diverse lipid species, including cholesterol, glycosphingolipids, sphingomyelin and sphingosine. The NPC1-mediated dysfunction of lipid transport has severe consequences for all brain cells, leading to neurodegeneration. Besides the cell-autonomous contribution of neuronal NPC1, aberrant NPC1 signalling in other brain cells is critical for the pathology. We discuss here the importance of endo-lysosomal dysfunction and a tight crosstalk between neurons, oligodendrocytes, astrocytes and microglia in NPC pathology. We strongly believe that a cell-specific rescue may not be sufficient to counteract the severity of the NPC pathology, but targeting common mechanisms, such as endo-lysosomal and lipid trafficking dysfunction, may ameliorate NPC pathology. This article is part of a discussion meeting issue 'Understanding the endo-lysosomal network in neurodegeneration'.
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Affiliation(s)
- Mariagiovanna Malara
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
| | - Matthias Prestel
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
| | - Sabina Tahirovic
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany
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10
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Castillo-Velasquez C, Matamala E, Becerra D, Orio P, Brauchi SE. Optical recordings of organellar membrane potentials and the components of membrane conductance in lysosomes. J Physiol 2024; 602:1637-1654. [PMID: 38625711 DOI: 10.1113/jp283825] [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: 06/14/2023] [Accepted: 03/20/2024] [Indexed: 04/17/2024] Open
Abstract
The eukaryotic cell is highly compartmentalized with organelles. Owing to their function in transporting metabolites, metabolic intermediates and byproducts of metabolic activity, organelles are important players in the orchestration of cellular function. Recent advances in optical methods for interrogating the different aspects of organellar activity promise to revolutionize our ability to dissect cellular processes with unprecedented detail. The transport activity of organelles is usually coupled to the transport of charged species; therefore, it is not only associated with the metabolic landscape but also entangled with membrane potentials. In this context, the targeted expression of fluorescent probes for interrogating organellar membrane potential (Ψorg) emerges as a powerful approach, offering less-invasive conditions and technical simplicity to interrogate cellular signalling and metabolism. Different research groups have made remarkable progress in adapting a variety of optical methods for measuring and monitoring Ψorg. These approaches include using potentiometric dyes, genetically encoded voltage indicators, hybrid fluorescence resonance energy transfer sensors and photoinduced electron transfer systems. These studies have provided consistent values for the resting potential of single-membrane organelles, such as lysosomes, the Golgi and the endoplasmic reticulum. We can foresee the use of dynamic measurements of Ψorg to study fundamental problems in organellar physiology that are linked to serious cellular disorders. Here, we present an overview of the available techniques, a survey of the resting membrane potential of internal membranes and, finally, an open-source mathematical model useful to interpret and interrogate membrane-bound structures of small volume by using the lysosome as an example.
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Affiliation(s)
- Cristian Castillo-Velasquez
- Department of Physiology, Faculty of Medicine, Universidad Austral de Chile, Valdivia, Chile
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Valdivia, Chile
| | - Ella Matamala
- Department of Physiology, Faculty of Medicine, Universidad Austral de Chile, Valdivia, Chile
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Valdivia, Chile
| | - Diego Becerra
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
| | - Patricio Orio
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaíso, Chile
- Instituto de Neurociencias, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Sebastian E Brauchi
- Department of Physiology, Faculty of Medicine, Universidad Austral de Chile, Valdivia, Chile
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Valdivia, Chile
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11
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Lachmayr H, Merrill AH. A Brief Overview of the Toxic Sphingomyelinase Ds of Brown Recluse Spider Venom and Other Organisms and Simple Methods To Detect Production of Its Signature Cyclic Ceramide Phosphate. Mol Pharmacol 2024; 105:144-154. [PMID: 37739813 PMCID: PMC10877732 DOI: 10.1124/molpharm.123.000709] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 08/05/2023] [Accepted: 08/29/2023] [Indexed: 09/24/2023] Open
Abstract
A special category of phospholipase D (PLD) in the venom of the brown recluse spider (Loxosceles reclusa) and several other sicariid spiders accounts for the dermonecrosis and many of the other clinical symptoms of envenomation. Related proteins are produced by other organisms, including fungi and bacteria. These PLDs are often referred to as sphingomyelinase Ds (SMase Ds) because they cleave sphingomyelin (SM) to choline and "ceramide phosphate." The lipid product has actually been found to be a novel sphingolipid: ceramide 1,3-cyclic phosphate (Cer1,3P). Since there are no effective treatments for the injury induced by the bites of these spiders, SMase D/PLDs are attractive targets for therapeutic intervention, and some of their features will be described in this minireview. In addition, two simple methods are described for detecting the characteristic SMase D activity using a fluorescent SM analog, (N-[12-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]dodecanoyl]-SM (C12-NBD-SM), that is cleaved to C12-NBD-Cer1,3P, which is easily separated from other potential metabolites by thin-layer chromatography and visualized under UV light. Besides confirming that C12-NBD-Cer1,3P is the only product detected upon incubation of C12-NBD-SM with brown recluse spider venom, the method was also able to detect for the first time very low levels of activity in venom from another spider, Kukulcania hibernalis The simplicity of the methods makes it relatively easy to determine this signature activity of SMase D/PLD. SIGNIFICANCE STATEMENT: The sphingomyelinase D/phospholipase D that are present in the venom of the brown recluse spider and other sources cause considerable human injury, but detection of the novel sphingolipid product, ceramide 1,3-cyclic phosphate, is not easy by previously published methods. This minireview describes simple methods for detection of this activity that will be useful for studies of its occurrence in spider venoms and other biological samples, perhaps including lesions from suspected spider bites and infections.
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Affiliation(s)
- Hannah Lachmayr
- School of Biological Sciences and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
| | - Alfred H Merrill
- School of Biological Sciences and the Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia
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12
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Antman-Passig M, Yaari Z, Goerzen D, Parikh R, Chatman S, Komer LE, Chen C, Grabarnik E, Mathieu M, Haimovitz-Friedman A, Heller DA. Nanoreporter Identifies Lysosomal Storage Disease Lipid Accumulation Intracranially. NANO LETTERS 2023; 23:10687-10695. [PMID: 37889874 PMCID: PMC11246544 DOI: 10.1021/acs.nanolett.3c02502] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/29/2023]
Abstract
Dysregulated lipid metabolism contributes to neurodegenerative pathologies and neurological decline in lysosomal storage disorders as well as more common neurodegenerative diseases. Niemann-Pick type A (NPA) is a fatal neurodegenerative lysosomal storage disease characterized by abnormal sphingomyelin accumulation in the endolysosomal lumen. The ability to monitor abnormalities in lipid homeostasis intracranially could improve basic investigations and the development of effective treatment strategies. We investigated the carbon nanotube-based detection of intracranial lipid content. We found that the near-infrared emission of a carbon nanotube-based lipid sensor responds to lipid accumulation in neuronal and in vivo models of NPA. The nanosensor detected lipid accumulation intracranially in an acid sphingomyelinase knockout mouse via noninvasive near-infrared spectroscopy. This work indicates a tool to improve drug development processes in NPA, other lysosomal storage diseases, and neurodegenerative diseases.
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Affiliation(s)
| | - Zvi Yaari
- Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Dana Goerzen
- Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Weill Cornell Medicine, Cornell University, New York, NY, 10065, USA
| | - Rooshi Parikh
- The City College of New York, New York, NY, 10031 USA
| | - Savannah Chatman
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, 63130, USA
- Engineering Program, Scripps College, Claremont, CA, 91711, USA
| | - Lauren E. Komer
- Helen and Robert Appel Alzheimer’s Disease Research Institute, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Chen Chen
- Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Weill Cornell Medicine, Cornell University, New York, NY, 10065, USA
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Emma Grabarnik
- Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Mickael Mathieu
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY,10065, USA
| | | | - Daniel A. Heller
- Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Weill Cornell Medicine, Cornell University, New York, NY, 10065, USA
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13
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Abstract
Pulmonary surfactant is a critical component of lung function in healthy individuals. It functions in part by lowering surface tension in the alveoli, thereby allowing for breathing with minimal effort. The prevailing thinking is that low surface tension is attained by a compression-driven squeeze-out of unsaturated phospholipids during exhalation, forming a film enriched in saturated phospholipids that achieves surface tensions close to zero. A thorough review of past and recent literature suggests that the compression-driven squeeze-out mechanism may be erroneous. Here, we posit that a surfactant film enriched in saturated lipids is formed shortly after birth by an adsorption-driven sorting process and that its composition does not change during normal breathing. We provide biophysical evidence for the rapid formation of an enriched film at high surfactant concentrations, facilitated by adsorption structures containing hydrophobic surfactant proteins. We examine biophysical evidence for and against the compression-driven squeeze-out mechanism and propose a new model for surfactant function. The proposed model is tested against existing physiological and pathophysiological evidence in neonatal and adult lungs, leading to ideas for biophysical research, that should be addressed to establish the physiological relevance of this new perspective on the function of the mighty thin film that surfactant provides.
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Affiliation(s)
- Fred Possmayer
- Department of Biochemistry, Western University, London, Ontario N6A 3K7, Canada
- Department of Obstetrics/Gynaecology, Western University, London, Ontario N6A 3K7, Canada
| | - Yi Y Zuo
- Department of Mechanical Engineering, University of Hawaii at Manon, Honolulu, Hawaii 96822, United States
- Department of Pediatrics, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii 96826, United States
| | - Ruud A W Veldhuizen
- Department of Physiology & Pharmacology, Western University, London, Ontario N6A 5C1, Canada
- Department of Medicine, Western University, London, Ontario N6A 3K7, Canada
- Lawson Health Research Institute, London, Ontario N6A 4V2, Canada
| | - Nils O Petersen
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
- Department of Chemistry, Western University, London, Ontario N6A 5B7, Canada
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14
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Zhao N, Deng G, Yuan PX, Zhang YF, Jiang LY, Zhao X, Song BL. TMEM241 is a UDP-N-acetylglucosamine transporter required for M6P modification of NPC2 and cholesterol transport. J Lipid Res 2023; 64:100465. [PMID: 37890669 PMCID: PMC10689955 DOI: 10.1016/j.jlr.2023.100465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 09/19/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Accurate intracellular cholesterol traffic plays crucial roles. Niemann Pick type C (NPC) proteins NPC1 and NPC2, are two lysosomal cholesterol transporters that mediate the cholesterol exit from lysosomes. However, other proteins involved in this process remain poorly defined. Here, we find that the previously unannotated protein TMEM241 is required for cholesterol egressing from lysosomes through amphotericin B-based genome-wide CRISPR-Cas9 KO screening. Ablation of TMEM241 caused impaired sorting of NPC2, a protein utilizes the mannose-6-phosphate (M6P) modification for lysosomal targeting, resulting in cholesterol accumulation in the lysosomes. TMEM241 is a member of solute transporters 35 nucleotide sugar transporters family and localizes on the cis-Golgi network. Our data indicate that TMEM241 transports UDP-N-acetylglucosamine (UDP-GlcNAc) into Golgi lumen and UDP-GlcNAc is used for the M6P modification of proteins including NPC2. Furthermore, Tmem241-deficient mice display cholesterol accumulation in pulmonary cells and behave pulmonary injury and hypokinesia. Taken together, we demonstrate that TMEM241 is a Golgi-localized UDP-GlcNAc transporter and loss of TMEM241 causes cholesterol accumulation in lysosomes because of the impaired M6P-dependent lysosomal targeting of NPC2.
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Affiliation(s)
- Nan Zhao
- The Institute for Advanced Studies, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Taikang Center for Life and Medical Sciences, Taikang Medical School, Wuhan University, Wuhan, China
| | - Gang Deng
- The Institute for Advanced Studies, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Taikang Center for Life and Medical Sciences, Taikang Medical School, Wuhan University, Wuhan, China
| | - Pei-Xin Yuan
- The Institute for Advanced Studies, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Taikang Center for Life and Medical Sciences, Taikang Medical School, Wuhan University, Wuhan, China
| | - Ya-Fen Zhang
- The Institute for Advanced Studies, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Taikang Center for Life and Medical Sciences, Taikang Medical School, Wuhan University, Wuhan, China
| | - Lu-Yi Jiang
- The Institute for Advanced Studies, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Taikang Center for Life and Medical Sciences, Taikang Medical School, Wuhan University, Wuhan, China
| | - Xiaolu Zhao
- The Institute for Advanced Studies, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Taikang Center for Life and Medical Sciences, Taikang Medical School, Wuhan University, Wuhan, China.
| | - Bao-Liang Song
- The Institute for Advanced Studies, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Taikang Center for Life and Medical Sciences, Taikang Medical School, Wuhan University, Wuhan, China.
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