Titel Deelnemers "Korte inhoud" "Local structural preferences in shaping tau amyloid polymorphism" "Nikolaos N Louros, Martin Wilkinson, Grigoria Tsaka, Meine Ramakers, Chiara Morelli, Teresa Garcia, Rodrigo Gallardo, Sam D'Haeyer, Vera Goossens, Dominique Audenaert, Dietmar Rudolf Thal, Ian R. Mackenzie, Rosa Rademakers, Neil A. Ranson, Sheena E. Radford, Frederic Rousseau, Joost Schymkowitz" "Tauopathies encompass a group of neurodegenerative disorders characterised by diverse tau amyloid fibril structures. The persistence of polymorphism across tauopathies suggests that distinct pathological conditions dictate the adopted polymorph for each disease. However, the extent to which intrinsic structural tendencies of tau amyloid cores contribute to fibril polymorphism remains uncertain. Using a combination of experimental approaches, we here identify a new amyloidogenic motif, PAM4 (Polymorphic Amyloid Motif of Repeat 4), as a significant contributor to tau polymorphism. Calculation of per-residue contributions to the stability of the fibril cores of different pathologic tau structures suggests that PAM4 plays a central role in preserving structural integrity across amyloid polymorphs. Consistent with this, cryo-EM structural analysis of fibrils formed from a synthetic PAM4 peptide shows that the sequence adopts alternative structures that closely correspond to distinct disease-associated tau strains. Furthermore, in-cell experiments revealed that PAM4 deletion hampers the cellular seeding efficiency of tau aggregates extracted from Alzheimer's disease, corticobasal degeneration, and progressive supranuclear palsy patients, underscoring PAM4's pivotal role in these tauopathies. Together, our results highlight the importance of the intrinsic structural propensity of amyloid core segments to determine the structure of tau in cells, and in propagating amyloid structures in disease. In this work, using a combination of Cryo-EM, in-cell experiments and biophysical analysis, the authors decoded the aggregation propensity of tau, revealing 5 central hot spots in its primary sequence and identify PAM4 as short segment that determines both the structure, as well as the cellular propagation of tau aggregates extracted from Alzheimer's disease, corticobasal degeneration, and progressive supranuclear palsy patients." "Whole-genome sequencing analysis reveals new susceptibility loci and structural variants associated with progressive supranuclear palsy" "Hui Wang, Timothy S. Chang, Beth A. Dombroski, Po-Liang Cheng, Vishakha Patil, Leopoldo Valiente-Banuet, Kurt Farrell, Catriona Mclean, Laura Molina-Porcel, Alex Rajput, Peter De Deyn, Nathalie Le Bastard, Marla Gearing, Laura Donker Kaat, John C. Van Swieten, Elise Dopper, Bernardino F. Ghetti, Kathy L. Newell, Claire Troakes, Justo G. de Yébenes, Alberto Rábano-Gutierrez, Tina Meller, Wolfgang H. Oertel, Gesine Resondek, Maria Stamelou, Thomas Arzberger, Sigrun Roeber, Ulrich Müller, Franziska Hopfner, Pau Pastor, Alexis Brice, Alexandra Durr, Isabelle Le Ber, Thomas G. Beach, Geidy Serrano, Lili-Naz Hazrati, Irene Litvan, Rosa Rademakers, Owen A. Ross, Douglas Galasko, Adam L. Boxer, Bruce L. Miller, William W. Seeley, Vivanna M. Van Deerlin, Edward B. Lee, Charles L. White III, Huw Morris, Rohan de Silva, John F. Crary, Alison M. Goate, Jeffrey S. Friedman, Yuk Yee Leung, Giovanni Coppola, Adam C. Naj, Li-San Wang, Dennis W. Dickson, Günter U. Höglinger, Gerard D. Schellenberg, Daniel H. Geschwind, Wan-Ping Lee" "Background Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease characterized by the accumulation of aggregated tau proteins in astrocytes, neurons, and oligodendrocytes. Previous genome-wide association studies for PSP were based on genotype array, therefore, were inadequate for the analysis of rare variants as well as larger mutations, such as small insertions/deletions (indels) and structural variants (SVs). Method In this study, we performed whole genome sequencing (WGS) and conducted association analysis for single nucleotide variants (SNVs), indels, and SVs, in a cohort of 1,718 cases and 2,944 controls of European ancestry. Of the 1,718 PSP individuals, 1,441 were autopsy-confirmed and 277 were clinically diagnosed. Results Our analysis of common SNVs and indels confirmed known genetic loci at MAPT, MOBP, STX6, SLCO1A2, DUSP10, and SP1, and further uncovered novel signals in APOE, FCHO1/MAP1S, KIF13A, TRIM24, TNXB, and ELOVL1. Notably, in contrast to Alzheimer’s disease (AD), we observed the APOE ε2 allele to be the risk allele in PSP. Analysis of rare SNVs and indels identified significant association in ZNF592 and further gene network analysis identified a module of neuronal genes dysregulated in PSP. Moreover, seven common SVs associated with PSP were observed in the H1/H2 haplotype region (17q21.31) and other loci, including IGH, PCMT1, CYP2A13, and SMCP. In the H1/H2 haplotype region, there is a burden of rare deletions and duplications (P = 6.73×10-3) in PSP. Conclusions Through WGS, we significantly enhanced our understanding of the genetic basis of PSP, providing new targets for exploring disease mechanisms and therapeutic interventions." "Neurite-based white matter alterations in MAPT mutation carriers" "Nick Corriveau-Lecavalier, Nirubol Tosakulwong, Timothy G. Lesnick, Angela J. Fought, Robert I. Reid, Christopher G. Schwarz, Matthew L. Senjem, Clifford R. Jack Jr, David T. Jones, Prashanthi Vemuri, Rosa Rademakers, Eliana Marisa Ramos, Daniel H. Geschwind, David S. Knopman, Hugo Botha, Rodolfo Savica, Jonathan Graff-Radford, Vijay K. Ramanan, Julie A. Fields, Neill Graff-Radford, Zbigniew Wszolek, Leah K. Forsberg, Ronald C. Petersen, Hilary W. Heuer, Adam L. Boxer, Howard J. Rosen, Bradley F. Boeve, Kejal Kantarci" "We assessed white matter (WM) integrity in MAPT mutation carriers (16 asymptomatic, 5 symptomatic) compared to 31 non-carrier family controls using diffusion tensor imaging (DTI) (fractional anisotropy; FA, mean diffusivity; MD) and neurite orientation dispersion and density imaging (NODDI) (neurite density index; NDI, orientation and dispersion index; ODI). Linear mixed-effects models accounting for age and family relatedness revealed alterations across DTI and NODDI metrics in all mutation carriers and in symptomatic carriers, with the most significant differences involving fronto-temporal WM tracts. Asymptomatic carriers showed higher entorhinal MD and lower cingulum FA and patterns of higher ODI mostly involving temporal areas and long association and projections fibers. Regression models between estimated time to or time from disease and DTI and NODDI metrics in key regions (amygdala, cingulum, entorhinal, inferior temporal, uncinate fasciculus) in all carriers showed increasing abnormalities with estimated time to or time from disease onset, with FA and NDI showing the strongest relationships. Neurite-based metrics, particularly ODI, appear to be particularly sensitive to early WM involvement in asymptomatic carriers." "The MAPT P.G324L and P.A406G mutations are associated with progressive supranuclear palsy with atypical features" "Negin Badihian, Farwa Ali, Hugo Botha, Rodolfo Savica, Mary M. Machulda, Heather M. Clark, Julie A.G. Stierwalt, Nha Trang Thu Pham, Matthew C. Baker, Rosa Rademakers, Val Lowe, Jennifer L. Whitwell, Keith A. Josephs" "Introduction: Progressive supranuclear palsy (PSP) is an atypical parkinsonism caused by the intracerebral aggregation of the microtubule-associated protein tau (MAPT) which is encoded by MAPT gene. Although PSP is a sporadic disease, MAPT mutations have been reported in rare cases.Methods: Among 190 patients with PSP who were recruited by the Neurodegenerative Research Group at Mayo Clinic during 2009-2023, we identified two patients who fulfilled diagnostic criteria for PSP-Richardson's syndrome (PSP-RS) and harbor novel MAPT mutations. To better investigate the potential effects of these mutations, we compared the clinical, and neuroimaging characteristics of these two patients to 20 randomly selected patients with PSP-RS without a MAPT mutation.Results: MAPT c.1024G > A, p. Glu342Lys, and MAPT c.1217 G > A, p. Arg406Gln mutations were found in 2 men who developed PSP-RS with atypical features at the ages of 60 and 62 years, respectively. Glu342Lys mutation was associated with features resembling alpha-synucleinopathies (autonomic dysfunction, dream enactment behavior), while both mutations were associated with features suggestive of Alzheimer's disease with poorer performance on tests of episodic memory. Comparison of F-18-flortaucipir uptake between the two MAPT mutation cases with 20 patients without a mutation revealed increased signal on flortaucipir-PET in bilateral medial temporal lobe regions (amygdala, entorhinal cortices, hippocampus, parahippocampus) but not in PSP-related regions (globus pallidum, midbrain, superior frontal cortex and dentate nucleus of the cerebellum).Conclusion: Glu342Lys and Arg406Gln mutations appear to modify the PSP-RS phenotype by targeting the medial temporal lobe regions resulting in more memory loss and greater flortaucipir uptake." "Assessing network degeneration and phenotypic heterogeneity in genetic frontotemporal lobar degeneration by decoding FDG-PET" "Nick Corriveau-Lecavalier, Leland R. Barnard, Scott A. Przybelski, Venkatsampath Gogineni, Hugo Botha, Jonathan Graff-Radford, Vijay K. Ramanan, Leah K. Forsberg, Julie A. Fields, Mary M. Machulda, Rosa Rademakers, Ralitza H. Gavrilova, Maria I. Lapid, Bradley F. Boeve, David S. Knopman, Val J. Lowe, Ronald C. Petersen, Clifford R. Jack, Kejal Kantarci, David T. Jones" "Genetic mutations causative of frontotemporal lobar degeneration (FTLD) are highly predictive of a specific proteinopathy, but there exists substantial inter-individual variability in their patterns of network degeneration and clinical manifestations. We collected clinical and 18Fluorodeoxyglucose-positron emission tomography (FDG-PET) data from 39 patients with genetic FTLD, including 11 carrying the C9orf72 hexanucleotide expansion, 16 carrying a MAPT mutation and 12 carrying a GRN mutation. We performed a spectral covariance decomposition analysis between FDG-PET images to yield unbiased latent patterns reflective of whole brain patterns of metabolism (""eigenbrains"" or EBs). We then conducted linear discriminant analyses (LDAs) to perform EB-based predictions of genetic mutation and predominant clinical phenotype (i.e., behavior/personality, language, asymptomatic). Five EBs were significant and explained 58.52 % of the covariance between FDGPET images. EBs indicative of hypometabolism in left frontotemporal and temporo-parietal areas distinguished GRN mutation carriers from other genetic mutations and were associated with predominant language phenotypes. EBs indicative of hypometabolism in prefrontal and temporopolar areas with a right hemispheric predominance were mostly associated with predominant behavioral phenotypes and distinguished MAPT mutation carriers from other genetic mutations. The LDAs yielded accuracies of 79.5 % and 76.9 % in predicting genetic status and predominant clinical phenotype, respectively. A small number of EBs explained a high proportion of covariance in patterns of network degeneration across FTLD-related genetic mutations. These EBs contained biological information relevant to the variability in the pathophysiological and clinical aspects of genetic FTLD, and for offering valuable guidance in complex clinical decision-making, such as decisions related to genetic testing." "Temporal course of cognitive and behavioural changes in motor neuron diseases" "Caroline A. McHutchison, Joanne Wuu, Corey T. McMillan, Rosa Rademakers, Jeffrey Statland, Gang Wu, Evadnie Rampersaud, Jason Myers, Jessica P. Hernandez, Sharon Abrahams, Michael Benatar" "BackgroundCognitive and behavioural dysfunction may occur in people with motor neuron disease (MND), with some studies suggesting an association with the C9ORF72 repeat expansion. Their onset and progression, however, is poorly understood. We explored how cognition and behaviour change over time, and whether demographic, clinical and genetic factors impact these changes.MethodsParticipants with MND were recruited through the Phenotype-Genotype-Biomarker study. Every 3-6 months, the Edinburgh Cognitive and Behavioural ALS Screen (ECAS) was used to assess amyotrophic lateral sclerosis (ALS) specific (executive functioning, verbal fluency, language) and ALS non-specific (memory, visuospatial) functions. Informants reported on behaviour symptoms via semi-structured interview.ResultsParticipants with neuropsychological data at >= 3 visits were included (n=237, mean age=59, 60% male), of which 18 (8%) were C9ORF72 positive. Baseline cognitive impairment was apparent in 18 (8%), typically in ALS specific domains, and associated with lower education, but not C9ORF72 status. Cognition, on average, remained stable over time, with two exceptions: (1) C9ORF72 carriers declined in all ECAS domains, (2) 8%-9% of participants with baseline cognitive impairment further declined, primarily in the ALS non-specific domain, which was associated with less education. Behavioural symptoms were uncommon.ConclusionsIn this study, cognitive dysfunction was less common than previously reported and remained stable over time for most. However, cognition declines longitudinally in a small subset, which is not entirely related to C9ORF72 status. Our findings raise questions about the timing of cognitive impairment in MND, and whether it arises during early clinically manifest disease or even prior to motor manifestations." "C-terminal TMEM106B fragments in human brain correlate with disease-associated TMEM106B haplotypes" "Cristina Teixeira Vicente, Jolien Perneel, Sarah Wynants, Bavo Heeman, Marleen Van den Broeck, Matt Baker, Simon Cheung, Júlia Faura Llorens, Ian R.A. Mackenzie, Rosa Rademakers" "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 (cryo-EM) studies showed that a C-terminal fragment (CTF) of TMEM106B (AA120-254) forms amyloid fibrils in the brain of patients with FTLD-TDP, but also in brains with other neurodegenerative conditions and normal aging 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 (IHC) 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 " "Case report" "Jolien Perneel, Masood Manoochehri, Edward D. Huey, Rosa Rademakers, Jill Goldman" "Frontotemporal dementia (FTD) is the second-most common young-onset dementia. Variants in the TMEM106B gene have been proposed as modifiers of FTD disease risk, especially in progranulin (GRN) mutation carriers. A patient in their 50s presented to our clinic with behavioral variant FTD (bvFTD). Genetic testing revealed the disease-causing variant c.349 + 1G > C in GRN. Family testing revealed that the mutation was inherited from an asymptomatic parent in their 80s and that the sibling also carries the mutation. Genetic analyses showed that the asymptomatic parent and sibling carry two copies of the protective TMEM106B haplotype (defined as c.554C > G, p.Thr185Ser), whereas the patient is heterozygous. This case report illustrates that combining TMEM106B genotyping with GRN mutation screening may provide more appropriate genetic counseling on disease risk in GRN families. Both the parent and sibling were counseled to have a significantly reduced risk for symptomatic disease. Implementing TMEM106B genotyping may also promote the collection of biosamples for research studies to improve our understanding of the risk-and disease-modifying effect of this important modifier gene." "The SERPINA5 coding variant E228Q does not contribute to clinicopathologic characteristics in Alzheimer's disease" "Billie J. Matchett, Sarah J. Lincoln, Matt Baker, Nikoleta Tamvaka, Sydney A. Labuzan, Tiffany Hicks N. Sirmans, Christina M. Moloney, Jacqueline Helminger, Kelly M. Hinkle, Janisse Cabrera-Rodriguez, Daniel P. Wickland, Patrick W. Johnson, Michael G. Heckman, Joseph S. Reddy, Steven G. Younkin, Minerva M. Carrasquillo, Ranjan Duara, Neill R. Graff-Radford, Cyril Pottier, Niluefer Ertekin-Taner, Owen A. Ross, Rosa Rademakers, Dennis W. Dickson, Melissa E. Murray" "We previously demonstrated that increased expression of the SERPINA5 gene is associated with hippocampal vulnerability in Alzheimer's disease (AD) brains. SERPINA5 was further demonstrated to be a novel tau-binding partner that colocalizes within neurofibrillary tangles. Our goal was to determine whether genetic variants in the SERPINA5 gene contributed to clinicopathologic phenotypes in AD. To screen for SERPINA5 variants, we sequenced 103 autopsy-confirmed young-onset AD cases with a positive family history of cognitive decline. To further assess the frequency of a rare missense variant, SERPINA5 p.E228Q, we screened an additional 1114 neuropathologically diagnosed AD cases. To provide neuropathologic context in AD, we immunohistochemically evaluated SERPINA5 and tau in a SERPINA5 p.E228Q variant carrier and a matched noncarrier. In the initial SERPINA5 screen, we observed 1 individual with a rare missense variant (rs140138746) that resulted in an amino acid change (p.E228Q). In our AD validation cohort, we identified an additional 5 carriers of this variant, resulting in an allelic frequency of 0.0021. There was no significant difference between SERPINA5 p.E228Q carriers and noncarriers in terms of demographic or clinicopathologic characteristics. Although not significant, on average SERPINA5 p.E228Q carriers were 5 years younger at age of disease onset than noncarriers (median: 66 [60-73] vs 71 [63-77] years, P = .351). In addition, SERPINA5 p.E228Q carriers exhibited a longer disease duration than noncarriers that approached significance (median: 12 [10-15]) vs 9 [6-12] years, P = .079). More severe neuronal loss was observed in the locus coeruleus, hippocampus, and amygdala of the SERPINA5 p.E228Q carrier compared to noncarrier, although no significant difference in SERPINA5-immunopositive lesions was observed. Throughout the AD brain in either carrier or noncarrier, areas with early pretangle pathology or burnt-out ghost tangle accumulation did not reveal SERPINA5-immunopositive neurons. Mature tangles and newly formed ghost tangles appeared to correspond well with SERPINA5-immunopositive tangle-bearing neurons. SERPINA5 gene expression was previously associated with disease phenotype; however, our findings suggest that SERPINA5 genetic variants may not be a contributing factor to clinicopathologic differences in AD. SERPINA5-immunopositive neurons appear to undergo a pathologic process that corresponded with specific levels of tangle maturity." "Comparison of clinical, genetic, and pathologic features of limbic and diffuse transactive response DNA-binding protein 43 pathology in Alzheimer's disease neuropathologic spectrum" "Arenn F. Carlos, Mary M. Machulda, Matthew H. Rutledge, Aivi T. Nguyen, R. Ross Reichard, Matthew C. Baker, Rosa Rademakers, Dennis W. Dickson, Ronald C. Petersen, Keith A. Josephs" "Background: Increasing evidence suggests that TAR DNA-binding protein 43 (TDP-43) pathology in Alzheimer's disease (AD), or AD-TDP, can be diffuse or limbic-predominant. Understanding whether diffuse AD-TDP has genetic, clinical, and pathological features that differ from limbic AD-TDP could have clinical and research implications. Objective: To better characterize the clinical and pathologic features of diffuse AD-TDP and differentiate it from limbic AD-TDP. Methods: 363 participants from the Mayo Clinic Study of Aging, Alzheimer's Disease Research Center, and Neurodegenerative Research Group with autopsy confirmed AD and TDP-43 pathology were included. All underwent genetic, clinical, neuropsychologic, and neuropathologic evaluations. AD-TDP pathology distribution was assessed using the Josephs 6-stage scale. Stages 1-3 were classified as Limbic, those 4-6 as Diffuse. Multivariable logistic regression was used to identify clinicopathologic features that independently predicted diffuse pathology. Results: The cohort was 61% female and old at onset (median: 76 years [IQR:70-82]) and death (median: 88 years [IQR:82-92]). Fifty-four percent were Limbic and 46% Diffuse. Clinically,similar to 10-20% increases in odds of being Diffuse associated with 5-year increments in age at onset (p = 0.04), 1-year longer disease duration (p = 0.02), and higher Neuropsychiatric Inventory scores (p = 0.03), while 15-second longer Trailmaking Test-B times (p = 0.02) and higher Block Design Test scores (p = 0.02) independently decreased the odds by similar to 10-15%. There was evidence for association of APOE epsilon 4 allele with limbic AD-TDP and of TMEM106B rs3173615 C allele with diffuse AD-TDP. Pathologically, widespread amyloid-beta plaques (Thal phases: 3-5) decreased the odds of diffuse TDP-43 pathology by 80-90%, while hippocampal sclerosis increased it sixfold (p < 0.001). Conclusion: Diffuse AD-TDP shows clinicopathologic and genetic features different from limbic AD-TDP."