Adam N. Trautwig, Edward J. Fox, Eric B. Dammer, Anantharaman Shantaraman, Lingyan Ping, Duc M. Duong, Caroline M. Watson, Fang Wu, Seneshaw Asress, Qi Guo, Allan I. Levey, James J. Lah, Federico Verde, Alberto Doretti, Antonia Ratti, Nicola Ticozzi, Cindy V. Ly, Timothy M. Miller, Mark A. Garret, James D. Berry, Eleanor V. Thomas, Christina N. Fournier, Zachary T. McEachin, Nicholas T. Seyfried, Jonathan D. Glass
{"title":"Network analysis of the cerebrospinal fluid proteome reveals shared and unique differences between sporadic and familial forms of amyotrophic lateral sclerosis","authors":"Adam N. Trautwig, Edward J. Fox, Eric B. Dammer, Anantharaman Shantaraman, Lingyan Ping, Duc M. Duong, Caroline M. Watson, Fang Wu, Seneshaw Asress, Qi Guo, Allan I. Levey, James J. Lah, Federico Verde, Alberto Doretti, Antonia Ratti, Nicola Ticozzi, Cindy V. Ly, Timothy M. Miller, Mark A. Garret, James D. Berry, Eleanor V. Thomas, Christina N. Fournier, Zachary T. McEachin, Nicholas T. Seyfried, Jonathan D. Glass","doi":"10.1186/s13024-025-00838-9","DOIUrl":"https://doi.org/10.1186/s13024-025-00838-9","url":null,"abstract":"Amyotrophic Lateral Sclerosis (ALS), a neurodegenerative disease involving loss of motor neurons, typically results in death within 3–5 years of disease onset. Although roughly 10% of cases can be linked to a specific inherited mutation (e.g., C9orf72 hexanucleotide repeat expansion or SOD1 mutation), the cause(s) of most cases are unknown. Consequently, there is a critical need for biomarkers that reflect disease onset and progression across ALS subgroups. We employed tandem mass tag mass spectrometry (TMT-MS) based proteomics on cerebrospinal fluid (CSF) to identify and quantify 2105 proteins from sporadic, C9orf72, and SOD1 ALS patients, asymptomatic C9orf72 expansion carriers, and controls (N = 101). To verify trends in our Emory University cohort we used data-independent acquisition (DIA-MS) on an expanded, four center cohort. This expanded cohort of 259 individuals included 50 sporadic ALS (sALS), 43 C9orf72 ALS, 22 SOD1 ALS, 72 asymptomatic gene carriers (59 C9orf72 and 13 SOD1) and 72 age-matched controls. We identified 2330 proteins and used differential protein abundance and network analyses to determine how protein profiles vary across disease subtypes in ALS CSF. Differential abundance and co-expression network analysis identified proteomic differences between ALS and control, as well as differentially abundant proteins between sporadic, C9orf72 and SOD1 ALS. A panel of proteins differentiated forms of ALS that are indistinguishable in a clinical setting. An additional panel differentiated asymptomatic from symptomatic C9orf72 and SOD1 mutation carriers, marking a pre-symptomatic proteomic signature of genetic forms of ALS. Leveraging this large, multicenter cohort, we validated our ALS CSF network and identified ALS-specific proteins and network modules. This study represents a comprehensive analysis of the CSF proteome across sporadic and genetic causes of ALS that resolves differences among these ALS subgroups and also identifies proteins that distinguish symptomatic from asymptomatic gene carriers. These new data point to varying pathogenic pathways that result in an otherwise clinically indistinguishable disease.","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"4 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143979449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mouse models of Anti-Aβ immunotherapies","authors":"Philip Pikus, R. Scott Turner, G. William Rebeck","doi":"10.1186/s13024-025-00836-x","DOIUrl":"https://doi.org/10.1186/s13024-025-00836-x","url":null,"abstract":"The development of anti-amyloid-beta (Aβ) immunotherapies as the first disease modifying therapy for Alzheimer’s Disease (AD) is a breakthrough of basic research and translational science. Genetically modified mouse models developed to study AD neuropathology and physiology were used for the discovery of Aβ immunotherapies and helped ultimately propel therapies to FDA approval. Nonetheless, the combination of modest efficacy and significant rates of an adverse side effect (amyloid related imaging abnormalities, ARIA), has prompted reverse translational research in these same mouse models to better understand the mechanism of the therapies. This review considers the use of these mouse models in understanding the mechanisms of Aβ clearance, cerebral amyloid angiopathy (CAA), blood brain barrier breakdown, neuroinflammation, and neuronal dysfunction in response to Aβ immunotherapy.","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"38 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143939765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Neil Donison, Jacqueline Palik, Kathryn Volkening, Michael J. Strong
{"title":"Cellular and molecular mechanisms of pathological tau phosphorylation in traumatic brain injury: implications for chronic traumatic encephalopathy","authors":"Neil Donison, Jacqueline Palik, Kathryn Volkening, Michael J. Strong","doi":"10.1186/s13024-025-00842-z","DOIUrl":"https://doi.org/10.1186/s13024-025-00842-z","url":null,"abstract":"Tau protein plays a critical role in the physiological functioning of the central nervous system by providing structural integrity to the cytoskeletal architecture of neurons and glia through microtubule assembly and stabilization. Under certain pathological conditions, tau is aberrantly phosphorylated and aggregates into neurotoxic fibrillary tangles. The aggregation and cell-to-cell propagation of pathological tau leads to the progressive deterioration of the nervous system. The clinical entity of traumatic brain injury (TBI) ranges from mild to severe and can promote tau aggregation by inducing cellular mechanisms and signalling pathways that increase tau phosphorylation and aggregation. Chronic traumatic encephalopathy (CTE), which is a consequence of repetitive TBI, is a unique tauopathy characterized by pathological tau aggregates located at the depths of the sulci and surrounding blood vessels. The mechanisms leading to increased tau phosphorylation and aggregation in CTE remain to be fully defined but are likely the result of the primary and secondary injury sequelae associated with TBI. The primary injury includes physical and mechanical damage resulting from the head impact and accompanying forces that cause blood–brain barrier disruption and axonal shearing, which primes the central nervous system to be more vulnerable to the subsequent secondary injury mechanisms. A complex interplay of neuroinflammation, oxidative stress, excitotoxicity, and mitochondrial dysfunction activate kinase and cell death pathways, increasing tau phosphorylation, aggregation and neurodegeneration. In this review, we explore the most recent insights into the mechanisms of tau phosphorylation associated with TBI and propose how multiple cellular pathways converge on tau phosphorylation, which may contribute to CTE progression. ","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"36 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143930936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evidence suggesting that microglia make amyloid from neuronally expressed APP: a hypothesis","authors":"John Hardy, Patrick Lewis","doi":"10.1186/s13024-025-00847-8","DOIUrl":"https://doi.org/10.1186/s13024-025-00847-8","url":null,"abstract":"While APP is largely neuonally expressed, Aβ amyloid is largely produced by microglia as the clearance mechanisms for damaged membranes becomes overwhelmed.","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"74 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143926604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wongu Youn, Mijin Yun, C. Justin Lee, Michael Schöll
{"title":"Cautions on utilizing plasma GFAP level as a biomarker for reactive astrocytes in neurodegenerative diseases","authors":"Wongu Youn, Mijin Yun, C. Justin Lee, Michael Schöll","doi":"10.1186/s13024-025-00846-9","DOIUrl":"https://doi.org/10.1186/s13024-025-00846-9","url":null,"abstract":"<p>In the recent decade, there has been a surge of efforts to develop scalable, specific and cost-effective biomarkers in blood to diagnose neurodegenerative diseases and prognose their progress even before overt symptoms manifest. Among an array of brain-associated proteins, glial fibrillary acidic protein (GFAP) has emerged as a compelling biomarker candidate, often in conjunction with other biomarkers. GFAP levels in bodily fluid, especially blood and cerebrospinal fluid (CSF), have underscored associations with disease progression by robust support in a substantial body of reports encompassing cohorts afflicted with a spectrum of brain and spinal cord disorders, including progressive neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s disease, multiple sclerosis and Lewy body dementia. Notably, GFAP in CSF is known to reflect astrogliosis in alignment with other astrogliosis marker levels such as S100β, chitinase-3-like protein 1 (CHI3L1, also known as YKL40 in humans and BMP39 in mice), aquaporin 4, evidence in tissue by immunohistochemistry staining, and uptake of certain PET radiotracers targeting reactive astrocytes, i.e., <sup>11</sup>C-deuterium-L-deprenyl (<sup>11</sup>C-DED), <sup>11</sup>C-BU99008, <sup>11</sup>C-SMBT-1 or <sup>11</sup> C-acetate [1]. On the other hand, GFAP levels in blood seem to demonstrate more precise diagnostic performance than CSF GFAP level in an AD context. Patient case studies employing MRI and PET have underscored correlations between disease progression and GFAP levels in bodily fluids, with plasma GFAP yielding greater significance [2]. Furthermore, recent cohort studies suggest that the effect of amyloid-β (Aβ) on tau pathology may be modulated by astrocytic reactivity, which was suggested to be indicated by increased plasma GFAP levels [3]. The recent inclusion of interchangeable use of plasma and CSF GFAP as a marker of inflammation (category ‘I’) in the Alzheimer’s Association Workgroup criteria for diagnosis and staging of Alzheimer’s disease showcases its suggested diagnostic potential [4]. We argue, however, that there are several concerns regarding the use of blood GFAP as a direct biomarker for astrocyte reactivity. Research has identified discrepancies between astrocyte reactivity examined by <sup>11</sup>C-deuterium-L-deprenyl (<sup>11</sup>C-DED) PET imaging and plasma GFAP levels in AD patients [5], with more significant changes observed in blood GFAP levels than in cerebrospinal fluid (CSF) GFAP levels [6]. In this perspective, we argue that astrocytic reactivity cannot be represented solely from blood GFAP level, and more direct methods for examining astrocyte reactivity such as PET imaging must be followed. Our argument is based on two primary concerns: the ambiguous origin of plasma GFAP and inconsistencies between blood GFAP level increases and other biomarkers.</p><p>First, the origin of blood GFAP remains unclear, with uncertainty about whether plasma GFAP derives","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"49 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143926636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Elise A. Kellett, Adekunle T. Bademosi, Adam K. Walker
{"title":"Molecular mechanisms and consequences of TDP-43 phosphorylation in neurodegeneration","authors":"Elise A. Kellett, Adekunle T. Bademosi, Adam K. Walker","doi":"10.1186/s13024-025-00839-8","DOIUrl":"https://doi.org/10.1186/s13024-025-00839-8","url":null,"abstract":"Increased phosphorylation of TDP-43 is a pathological hallmark of several neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). However, the regulation and roles of TDP-43 phosphorylation remain incompletely understood. A variety of techniques have been utilized to understand TDP-43 phosphorylation, including kinase/phosphatase manipulation, phosphomimic variants, and genetic, physical, or chemical inducement in a variety of cell cultures and animal models, and via analyses of post-mortem human tissues. These studies have produced conflicting results: suggesting incongruously that TDP-43 phosphorylation may either drive disease progression or serve a neuroprotective role. In this review, we explore the roles of regulators of TDP-43 phosphorylation including the putative TDP-43 kinases c-Abl, CDC7, CK1, CK2, IKKβ, p38α/MAPK14, MEK1, TTBK1, and TTBK2, and TDP-43 phosphatases PP1, PP2A, and PP2B, in disease. Building on recent studies, we also examine the consequences of TDP-43 phosphorylation on TDP-43 pathology, especially related to TDP-43 mislocalisation, liquid–liquid phase separation, aggregation, and neurotoxicity. By comparing conflicting findings from various techniques and models, this review highlights both the discrepancies and unresolved aspects in the understanding of TDP-43 phosphorylation. We propose that the role of TDP-43 phosphorylation is site and context dependent, and includes regulation of liquid–liquid phase separation, subcellular mislocalisation, and degradation. We further suggest that greater consideration of the normal functions of the regulators of TDP-43 phosphorylation that may be perturbed in disease is warranted. This synthesis aims to build towards a comprehensive understanding of the complex role of TDP-43 phosphorylation in the pathogenesis of neurodegeneration. TDP-43 is subject to phosphorylation by kinases and dephosphorylation by phosphatases, which variably impacts protein localisation, aggregation, and neurotoxicity in neurodegenerative diseases. ","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"74 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143920371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cerebrospinal fluid proteome profiling across the Alzheimer's disease continuum: a step towards solving the equation for 'X'.","authors":"Sophia Weiner,Mathias Sauer,Laia Montoliu-Gaya,Andrea L Benedet,Nicholas J Ashton,Fernando Gonzalez-Ortiz,Joel Simrén,Nesrine Rahmouni,Cecile Tissot,Joseph Therriault,Stijn Servaes,Jenna Stevenson,Ville Leinonen,Tuomas Rauramaa,Mikko Hiltunen,Pedro Rosa-Neto,Kaj Blennow,Henrik Zetterberg,Johan Gobom","doi":"10.1186/s13024-025-00841-0","DOIUrl":"https://doi.org/10.1186/s13024-025-00841-0","url":null,"abstract":"BACKGROUNDWhile the temporal profile of amyloid (Aβ) and tau cerebrospinal fluid (CSF) biomarkers along the Alzheimer's disease (AD) continuum is well-studied, chronological changes of CSF proteins reflecting other disease-relevant processes, denoted 'X' in the ATX(N) framework, remain poorly understood.METHODSUsing an untargeted mass spectrometric approach termed tandem mass tag (TMT), we quantified over 1500 CSF proteins across the AD continuum in three independent cohorts, finely staged by Aβ/tau positron emission tomography (PET), fluid biomarkers, or brain biopsy. Weighted protein co-expression network analysis identified clusters of proteins robustly correlating in all three cohorts which sequentially changed with AD progression. Obtained protein clusters were correlated with fluid biomarker measurements (phosphorylated tau (p-tau) species including p-tau181, p-tau217, and p-tau205, as well as Aβ), Aβ/tau PET imaging, and clinical parameters to discern disease-relevant clusters which were modelled across the AD continuum.RESULTSNeurodegeneration-related proteins (e.g., 14-3-3 proteins, PPIA), derived from different brain cell types, strongly correlated with fluid as well as imaging biomarkers and increased early in the AD continuum. Among them, the proteins SMOC1 and CNN3 were highly associated with Aβ pathology, while the 14-3-3 proteins YWHAZ and YWHAE as well as PPIA demonstrated a strong association with both Aβ and tau pathology as indexed by PET. Endo-lysosomal proteins (e.g., HEXB, TPP1, SIAE) increased early in abundance alongside neurodegeneration-related proteins, and were followed by increases in metabolic proteins such as ALDOA, MDH1, and GOT1 at the mild cognitive impairment (MCI) stage. Finally, later AD stages were characterized by decreases in synaptic/membrane proteins (e.g., NPTX2).CONCLUSIONSOur study identified proxies of Aβ and tau pathology, indexed by PET, (SMOC1, YWHAE, CNN3) and highlighted the dynamic fluctuations of the CSF proteome over the disease course, identifying candidate biomarkers for disease staging beyond Aβ and tau.","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"38 1","pages":"52"},"PeriodicalIF":15.1,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143915209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaojie Zhao, Yan Li, Siwei Zhang, Ari Sudwarts, Hanwen Zhang, Alena Kozlova, Matthew J. Moulton, Lindsey D. Goodman, Zhiping P. Pang, Alan R. Sanders, Hugo J. Bellen, Gopal Thinakaran, Jubao Duan
{"title":"Alzheimer’s disease protective allele of Clusterin modulates neuronal excitability through lipid-droplet-mediated neuron-glia communication","authors":"Xiaojie Zhao, Yan Li, Siwei Zhang, Ari Sudwarts, Hanwen Zhang, Alena Kozlova, Matthew J. Moulton, Lindsey D. Goodman, Zhiping P. Pang, Alan R. Sanders, Hugo J. Bellen, Gopal Thinakaran, Jubao Duan","doi":"10.1186/s13024-025-00840-1","DOIUrl":"https://doi.org/10.1186/s13024-025-00840-1","url":null,"abstract":"Genome-wide association studies (GWAS) of Alzheimer’s disease (AD) have identified a plethora of risk loci. However, the disease variants/genes and the underlying mechanisms have not been extensively studied. Bulk ATAC-seq was performed in induced pluripotent stem cells (iPSCs) differentiated various brain cell types to identify allele-specific open chromatin (ASoC) SNPs. CRISPR-Cas9 editing generated isogenic pairs, which were then differentiated into glutamatergic neurons (iGlut). Transcriptomic analysis and functional studies of iGlut co-cultured with mouse astrocytes assessed neuronal excitability and lipid droplet formation. We identified a putative causal SNP of CLU that impacted neuronal chromatin accessibility to transcription-factor(s), with the AD protective allele upregulating neuronal CLU and promoting neuron excitability. And, neuronal CLU facilitated neuron-to-glia lipid transfer and astrocytic lipid droplet formation coupled with reactive oxygen species (ROS) accumulation. These changes caused astrocytes to uptake less glutamate thereby altering neuron excitability. For a strong AD-associated locus near Clusterin (CLU), we connected an AD protective allele to a role of neuronal CLU in promoting neuron excitability through lipid-mediated neuron-glia communication. Our study provides insights into how CLU confers resilience to AD through neuron-glia interactions.","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"54 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Henna Martiskainen, Roosa-Maria Willman, Päivi Harju, Sami Heikkinen, Mette Heiskanen, Stephan A. Müller, Rosa Sinisalo, Mari Takalo, Petra Mäkinen, Teemu Kuulasmaa, Viivi Pekkala, Ana Galván del Rey, Sini-Pauliina Juopperi, Heli Jeskanen, Inka Kervinen, Kirsi Saastamoinen, Marja Niiranen, Sami V. Heikkinen, Mitja I. Kurki, Jarkko Marttila, Petri I. Mäkinen, Hannah Rostalski, Tomi Hietanen, Tiia Ngandu, Jenni Lehtisalo, Céline Bellenguez, Jean-Charles Lambert, Christian Haass, Juha Rinne, Juhana Hakumäki, Tuomas Rauramaa, Johanna Krüger, Hilkka Soininen, Annakaisa Haapasalo, Stefan F. Lichtenthaler, Ville Leinonen, Eino Solje, Mikko Hiltunen
{"title":"Monoallelic TYROBP deletion is a novel risk factor for Alzheimer’s disease","authors":"Henna Martiskainen, Roosa-Maria Willman, Päivi Harju, Sami Heikkinen, Mette Heiskanen, Stephan A. Müller, Rosa Sinisalo, Mari Takalo, Petra Mäkinen, Teemu Kuulasmaa, Viivi Pekkala, Ana Galván del Rey, Sini-Pauliina Juopperi, Heli Jeskanen, Inka Kervinen, Kirsi Saastamoinen, Marja Niiranen, Sami V. Heikkinen, Mitja I. Kurki, Jarkko Marttila, Petri I. Mäkinen, Hannah Rostalski, Tomi Hietanen, Tiia Ngandu, Jenni Lehtisalo, Céline Bellenguez, Jean-Charles Lambert, Christian Haass, Juha Rinne, Juhana Hakumäki, Tuomas Rauramaa, Johanna Krüger, Hilkka Soininen, Annakaisa Haapasalo, Stefan F. Lichtenthaler, Ville Leinonen, Eino Solje, Mikko Hiltunen","doi":"10.1186/s13024-025-00830-3","DOIUrl":"https://doi.org/10.1186/s13024-025-00830-3","url":null,"abstract":"Biallelic loss-of-function variants in TYROBP and TREM2 cause autosomal recessive presenile dementia with bone cysts known as Nasu-Hakola disease (NHD, alternatively polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy, PLOSL). Some other TREM2 variants contribute to the risk of Alzheimer’s disease (AD) and frontotemporal dementia, while deleterious TYROBP variants are globally extremely rare and their role in neurodegenerative diseases remains unclear. The population history of Finns has favored the enrichment of deleterious founder mutations, including a 5.2 kb deletion encompassing exons 1–4 of TYROBP and causing NHD in homozygous carriers. We used here a proxy marker to identify monoallelic TYROBP deletion carriers in the Finnish biobank study FinnGen combining genome and health registry data of 520,210 Finns. We show that monoallelic TYROBP deletion associates with an increased risk and earlier onset age of AD and dementia when compared to noncarriers. In addition, we present the first reported case of a monoallelic TYROBP deletion carrier with NHD-type bone cysts. Mechanistically, monoallelic TYROBP deletion leads to decreased levels of DAP12 protein (encoded by TYROBP) in myeloid cells. Using transcriptomic and proteomic analyses of human monocyte-derived microglia-like cells, we show that upon lipopolysaccharide stimulation monoallelic TYROBP deletion leads to the upregulation of the inflammatory response and downregulation of the unfolded protein response when compared to cells with two functional copies of TYROBP. Collectively, our findings indicate TYROBP deletion as a novel risk factor for AD and suggest specific pathways for therapeutic targeting.","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"8 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143884381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria Vizziello, Ilaria Linda Dellarole, Arianna Ciullini, Riccardo Pascuzzo, Annalisa Lombardo, Floriana Bellandi, Luigi Celauro, Claudia Battipaglia, Emilio Ciusani, Ambra Rizzo, Marcella Catania, Grazia Devigili, Sara Adriana Della Seta, Valentina Margiotta, Monica Consonni, Veronica Faltracco, Pietro Tiraboschi, Nilo Riva, Sara Maria Silvia Portaleone, Gianluigi Zanusso, Giuseppe Legname, Giuseppe Lauria, Eleonora Dalla Bella, Fabio Moda
{"title":"TDP-43 seeding activity in the olfactory mucosa of patients with amyotrophic lateral sclerosis","authors":"Maria Vizziello, Ilaria Linda Dellarole, Arianna Ciullini, Riccardo Pascuzzo, Annalisa Lombardo, Floriana Bellandi, Luigi Celauro, Claudia Battipaglia, Emilio Ciusani, Ambra Rizzo, Marcella Catania, Grazia Devigili, Sara Adriana Della Seta, Valentina Margiotta, Monica Consonni, Veronica Faltracco, Pietro Tiraboschi, Nilo Riva, Sara Maria Silvia Portaleone, Gianluigi Zanusso, Giuseppe Legname, Giuseppe Lauria, Eleonora Dalla Bella, Fabio Moda","doi":"10.1186/s13024-025-00833-0","DOIUrl":"https://doi.org/10.1186/s13024-025-00833-0","url":null,"abstract":"In recent years, the seed amplification assay (SAA) has enabled the identification of pathological TDP-43 in the cerebrospinal fluid (CSF) and olfactory mucosa (OM) of patients with genetic forms of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Here, we investigated the seeding activity of TDP-43 in OM samples collected from patients with sporadic ALS. OM samples were collected from patients with (a) sporadic motor neuron diseases (MND), including spinal ALS (n = 35), bulbar ALS (n = 18), primary lateral sclerosis (n = 10), and facial onset sensory and motor neuronopathy (n = 2); (b) genetic MND, including carriers of C9orf72exp (n = 6), TARDBP (n = 4), SQSTM1 (n = 3), C9orf72exp + SQSTM1 (n = 1), OPTN (n = 1), GLE1 (n = 1), FUS (n = 1) and SOD1 (n = 4) mutations; (c) other neurodegenerative disorders (OND), including Alzheimer’s disease (n = 3), dementia with Lewy bodies (n = 8) and multiple system atrophy (n = 6); and (d) control subjects (n = 22). All samples were subjected to SAA analysis for TDP-43 (TDP-43_SAA). Plasmatic levels of TDP-43 and neurofilament-light chain (NfL) were also assessed in a selected number of patients. TDP-43_SAA was positive in 29/65 patients with sporadic MND, 9/21 patients with genetic MND, 6/17 OND patients and 3/22 controls. Surprisingly, one presymptomatic individual also tested positive. As expected, OM of genetic non-TDP-43-related MND tested negative. Interestingly, fluorescence values from non-MND samples that tested positive were consistently and significantly lower than those obtained with sporadic and genetic MND. Furthermore, among TDP-43-positive samples, the lag phase observed in MND patients was significantly longer than that in non-MND patients. Plasma TDP-43 levels were significantly higher in sporadic MND patients compared to controls and decreased as the disease progressed. Similarly, plasma NfL levels were higher in both sporadic and genetic MND patients and positively correlated with disease progression rate (ΔFS). No significant correlations were detected between TDP-43_SAA findings and the biological, clinical, or neuropsychological parameters considered. The OM of a subset of patients with sporadic MND can trigger seeding activity for TDP-43, as previously observed in genetic MND. Thus, TDP-43_SAA analysis of OM can improve the clinical characterization of ALS across different phenotypes and enhance our understanding of these diseases. Finally, plasma TDP-43 could serve as a potential biomarker for monitoring disease progression. However, further research is needed to confirm and expand these findings.","PeriodicalId":18800,"journal":{"name":"Molecular Neurodegeneration","volume":"14 1","pages":""},"PeriodicalIF":15.1,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143878120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}